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Dr. Javier Romero, MD
Radiologist, Surgeon
20 years of experience
Accepting new patients
Video profile

Credentials

Education ?

Medical School
Universidad El Bosque (1992)
Foreign school
Residency
Fundacion Santa Fe de Bogata *
Vascular Neurology
Fellowship
Massachusetts General Hospital (2004) *
Neuroradiology
* This information was reported to Vitals by the doctor or doctor's office.

Awards & Distinctions ?

Awards  
Patients' Choice Award (2008 - 2009, 2013)
Compassionate Doctor Recognition (2013)
Appointments
Harvard University (1998 - Present)
Assistant Professor
Massachusetts General Hospital (1998 - Present)
Neuroradiologist

Affiliations ?

Dr. Romero is affiliated with 2 hospitals.

Hospital Affiliations

Score

Rankings

  • Massachusetts General Hospital *
    55 Fruit St, Boston, MA 02114
    •  
    Top 25%
  • Boston: Massachusetts General Hospital *
  • Publications & Research

    Dr. Romero has contributed to 110 publications.
    Title Advanced Ct Imaging in the Evaluation of Hemorrhagic Stroke.
    Date March 2012
    Journal Neuroimaging Clinics of North America
    Excerpt

    Multidetector computed tomographic (CT) angiography is rapidly becoming a pivotal examination in the initial evaluation of patients with hemorrhagic stroke. This article provides an update of the literature on this dynamic topic, focusing on (1) the utility of CT angiography in the identification of hemorrhagic stroke patients who harbor an underlying vascular etiology and the role of the secondary intracerebral hemorrhage score, as well as (2) the clinical value of the CT angiography spot sign and spot sign score in patients with primary intracerebral hemorrhage.

    Title Taut Internal Limiting Membrane Causing Diffuse Diabetic Macular Edema After Vitrectomy: Clinicopathological Correlation.
    Date November 2011
    Journal Ophthalmologica. Journal International D'ophtalmologie. International Journal of Ophthalmology. Zeitschrift Für Augenheilkunde
    Excerpt

    To describe 2 cases of diffuse diabetic macular edema (DME) after diabetic vitrectomy caused by a taut internal limiting membrane (ILM), with clinicopathological correlation.

    Title Apoe Genotype and Extent of Bleeding and Outcome in Lobar Intracerebral Haemorrhage: a Genetic Association Study.
    Date September 2011
    Journal Lancet Neurology
    Excerpt

    Carriers of APOE ε2 and ε4 have an increased risk of intracerebral haemorrhage (ICH) in lobar regions, presumably because of the effects of these gene variants on risk of cerebral amyloid angiopathy. We aimed to assess whether these variants also associate with severity of ICH, in terms of haematoma volume at presentation and subsequent outcome.

    Title Practical Scoring System for the Identification of Patients with Intracerebral Hemorrhage at Highest Risk of Harboring an Underlying Vascular Etiology: the Secondary Intracerebral Hemorrhage Score.
    Date February 2011
    Journal Ajnr. American Journal of Neuroradiology
    Excerpt

    An ICH patient's risk of harboring an underlying vascular etiology varies according to baseline clinical and NCCT characteristics. Our aim was to develop a practical scoring system to stratify patients with ICH according to their risk of harboring a vascular etiology.

    Title Analysis of Hla-abc Locus-specific Transcription in Normal Tissues.
    Date November 2010
    Journal Immunogenetics
    Excerpt

    We developed a novel human leukocyte antigen HLA-ABC locus-specific quantitative real-time polymerase chain reaction (PCR) to determine the locus-specific gene expression of HLA-ABC in peripheral blood leukocytes (PBLs, n = 53), colon mucosa (n = 15), and larynx mucosa (n = 15). Laser-assisted tissue microdissection allowed us to study the selected cells without interference from surrounding stroma. We report evidence on the specificity of the technique, describing the HLA-ABC locus-specific gene expression patterns found in the PBLs and two solid tissues studied. PBLs showed a higher gene expression of HLA-B than of HLA-A or HLA-C (p = 4.7 × 10(-10) and p = 1.6 × 10(-6), respectively). In solid tissue, HLA-A and HLA-B gene expressions were similar and HLA-C expression lower. In particular, in larynx mucosa, significant differences were found between HLA-A and HLA-C expressions and between HLA-B and HLA-C expressions (p = 6.5 × 10(-4) and p = 8.1 × 10(-4), respectively). The same differences were observed in colon mucosa, but significance was not reached (p = 0.08 and p = 0.06, respectively). Differences in locus-specific regulation may be related to the control of cytotoxic responses of NK and CD8 positive T cells. Gene expression of HLA-ABC specific locus showed no intra-individual variability, but there was a high inter-individual variability. This may result from differences in the expression of common regulatory factors that control HLA-ABC constitutive expression.

    Title [primary Autoimmune Hypothyroidism in Patients with Pernicious Anemia].
    Date September 2010
    Journal Revista Clínica Española
    Title Case Records of the Massachusetts General Hospital. Case 21-2010. A Request for Retrieval of Oocytes from a 36-year-old Woman with Anoxic Brain Injury.
    Date July 2010
    Journal The New England Journal of Medicine
    Title Computed Tomography Angiography of the Carotid and Cerebral Circulation.
    Date July 2010
    Journal Radiologic Clinics of North America
    Excerpt

    As a result of the development of multidetector row computed tomography (CT) technology, multidetector CT angiography is rapidly becoming the preferred examination for the initial evaluation of an increasing number of clinical neurovascular applications such as carotid artery steno-occlusive disease, acute ischemic and hemorrhagic stroke, subarachnoid hemorrhage, and cerebral vasospasm. This article reviews the most recent literature on these topics, provides the reader with useful clinical tips for performing and interpreting these increasingly complex diagnostic examinations, presents illustrative cases, and looks at future developments in this vibrant area of neuroradiology research.

    Title Prevalence of Traumatic Dural Venous Sinus Thrombosis in High-risk Acute Blunt Head Trauma Patients Evaluated with Multidetector Ct Venography.
    Date May 2010
    Journal Radiology
    Excerpt

    To determine the prevalence of trauma-related dural venous sinus thrombosis (DVST) in high-risk patients with blunt head trauma who are examined with multidetector computed tomographic (CT) venography.

    Title Comparison of Hematoma Shape and Volume Estimates in Warfarin Versus Non-warfarin-related Intracerebral Hemorrhage.
    Date May 2010
    Journal Neurocritical Care
    Excerpt

    Hematoma volume is a major determinant of outcome in patients with intracerebral hemorrhage (ICH). Accurate volume measurements are critical for predicting outcome and are thought to be more difficult in patients with oral anticoagulation-related ICH (OAT-ICH) due to a higher frequency of irregular shape. We examined hematoma shape and methods of volume assessment in patients with OAT-ICH.

    Title Detection of Common Carotid Artery Stenosis Using Duplex Ultrasonography: a Validation Study with Computed Tomographic Angiography.
    Date February 2010
    Journal Journal of Vascular Surgery : Official Publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter
    Excerpt

    Severe stenosis of the common carotid artery (CCA), while uncommon, is associated with increased risk of transient ischemic attack and stroke. To date, no validated duplex ultrasound criteria have been established for grading the severity of CCA stenosis. The goal of this study was to use receiver-operating curve (ROC) analysis with computed tomographic angiography as the reference standard to establish duplex ultrasound criteria for diagnosing >or=50% CCA stenosis.

    Title The Spot Sign Score in Primary Intracerebral Hemorrhage Identifies Patients at Highest Risk of In-hospital Mortality and Poor Outcome Among Survivors.
    Date January 2010
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    The spot sign score is a potent predictor of hematoma expansion in patients with primary intracerebral hemorrhage (ICH). We aim to determine the accuracy of this scoring system for the prediction of in-hospital mortality and poor outcome among survivors in patients with primary ICH.

    Title Multidetector Ct Angiography in the Evaluation of Acute Blunt Head and Neck Trauma: a Proposed Acute Craniocervical Trauma Scoring System.
    Date January 2010
    Journal Radiology
    Excerpt

    To determine the diagnostic yield of multidetector computed tomographic (CT) angiography in the evaluation of patients presenting to the emergency department with acute blunt head and neck trauma to assess for arterial injury and to propose a practical scoring system for the identification of patients at highest risk of arterial injury.

    Title [usefulness of Hyperbaric Oxygen in the Treatment of Radionecrosis and Symptomatic Brain Edema After Linac Radiosurgery].
    Date January 2010
    Journal Neurocirugía (asturias, Spain)
    Excerpt

    Radionecrosis with brain edema is a complication of radiosurgery. Three female patients harbouring a frontal pole, petrous and parasagital parietoocipital meningiomas respectively who had been treated with LINAC radiosurgery are presented. Those patients developed, between two and eight months later, a severe symptomatic radionecrosis with a huge brain edema resistant to the usual steroid therapy. Only after 40 sessions of hyperbaric oxygen, a good remission of the lesions was obtained. There are few cases reported in the literature with such a good outcome. Consequentely, this therapy must be taken into account to treat this type of radiosurgical complication before considering surgery.

    Title Evolutionarily Conserved Photoperiod Mechanisms in Plants: when Did Plant Photoperiodic Signaling Appear?
    Date November 2009
    Journal Plant Signaling & Behavior
    Excerpt

    Day-length and the circadian clock control critical aspects of plant development such as the onset of reproduction by the photoperiodic pathway. CONSTANS (CO) regulates the expression of a florigenic mobile signal from leaves to the apical meristem and thus is central to the regulation of photoperiodic flowering. This regulatory control is present in all higher plants, but the time in evolution when it arose was unknown. We have shown that the genomes of green microalgae encode members of the CONSTANS-like (COL) protein family. One of these genes, the Chlamydomonas reinhardtii CO homolog (CrCO), can complement the co mutation in Arabidopsis. CrCO expression is controlled by the clock and photoperiod in Chlamydomonas and at the same time is involved in the correct timing of several circadian output processes such as the accumulation of starch or the coordination of cell growth and division. We have proposed that, since very early in the evolutionary lineage that gave rise to higher plants, CO homologs have been involved in the photoperiod control of important developmental processes, and that the recruitment of COL proteins in other roles may have been crucial for their evolutionary success.

    Title Aortofemoral Bypass to Bridge End-stage Renal Disease Patients with Severe Iliac Calcification to Kidney Transplantation.
    Date November 2009
    Journal Vascular
    Excerpt

    Patients undergoing hemodialysis have a lower survival rate than those who receive a kidney transplant. Mortality among hemodialysis patients is approximately 14.5% compared with 1.5% for transplant recipients. One of the exclusion criteria for renal transplant is severe iliac artery calcification. We performed an aortofemoral bypass in these patients to make them eligible for renal transplantation. Eleven patients were selected to receive an aortofemoral bypass. All had severe calcification of iliac arteries. Eight patients required a bypass from the thoracic aorta and two from the infrarenal level. Revascularization was successful in 10 patients. Patency was 100%. Surgery could not be performed in one owing to severe calcification of the femoral artery. One patient died owing to gastrointestinal bleeding. Two patients developed complications; one needed a splenectomy, and the other developed meningitis and paralytic ileus. To date, four patients have received transplants, and the viability of the transplanted kidney is good in all cases. Renal transplantation is the only method known to improve survival and quality of life for hemodialysis patients. We consider that if patients with severe iliac calcification are well informed of the morbidity and mortality risk of an aortic bypass, this intervention can be justified in this setting.

    Title [polymorphisms in Inflammatory Response Genes in Metastatic Renal Cancer].
    Date September 2009
    Journal Actas Urologicas Españolas
    Excerpt

    Inflammation has been implicated as an etiological factor in different human cancers. Allelic variations in the genes implicated in inflammation are candidates as genetic determinants or markers of renal carcinoma risk. The present stud investigates whether polymorphisms of the genes that give rise to increases in the levels of proinflammatory cytokines and chemokines are associated with an increased risk of renal carcinoma. To this effect, a number of case-control studies were designed to assess the correlation between renal carcinoma and polymorphisms IL10-1082 A/G (rs 1800896), IL10-592 A/C (rs 1800872), IL10-819 C/T (rs 1800871), IL10-1082 A/G, IL4-590 C/T (rs 2243250), TNF-A-308 A/G (rs 1800629), RANTES-403 G/A (rs 2107538), IL1-A-889 C/T (rs 1800587), MCP-1 2518 G/A (rs 1024611), CTLA-4/+49 A/G (rs 231775) and CTLA-4 CT60 A/G (rs 3087243) in 127 renal carcinoma patients and in 176 healthy subjects. The results obtained in relation to cytokine polymorphism IL-10-1082 A/G indicate that AG heterozygosity status is the principal risk factor in relation to locally advanced or metastatic tumor stage and renal carcinoma. In the case of the molecule CTLA4, the results obtained in renal cancer reveal an association between the polymorphisms of the CTLA-4 gene and an increased risk of developing renal cell carcinoma. A high genotypic frequency of polymorphisms CTLA4/CT60-AA and CTLA4/A49G-AA is observed in patients with renal cell carcinoma versus the controls. An association has been established between polymorphism CTLA4/CT60 and tumor grade in patients with renal cell carcinoma. Logistic regression analysis has confirmed these data, demonstrating a high frequency of the AA genotype in patients with high-grade tumors. The results obtained support the hypothesis that different genetic factors implicated in the regulation of adaptive immune responses, stromal cell composition and local cytokine production levels may be crucial elements in the modification of the clinicopathological parameters of renal carcinoma.

    Title Systematic Characterization of the Computed Tomography Angiography Spot Sign in Primary Intracerebral Hemorrhage Identifies Patients at Highest Risk for Hematoma Expansion: the Spot Sign Score.
    Date September 2009
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    The presence of active contrast extravasation (the spot sign) on computed tomography (CT) angiography has been recognized as a predictor of hematoma expansion in patients with intracerebral hemorrhage. We aim to systematically characterize the spot sign to identify features that are most predictive of hematoma expansion and construct a spot sign scoring system.

    Title Accuracy of Ct Angiography for the Diagnosis of Vascular Abnormalities Causing Intraparenchymal Hemorrhage in Young Patients.
    Date August 2009
    Journal Emergency Radiology
    Excerpt

    The objective of this study is to measure the accuracy of multidetector CT angiography (MD CTA) in the detection of vascular abnormalities in patients <or=40 years with spontaneous intraparenchymal hemorrhage (IPH) presenting to the emergency department. After institutional review board approval, a retrospective study was performed of 43 consecutive patients <or=40 years, who presented to our emergency department with IPH and that were evaluated with MD CTA. MD CTA images were reviewed by a neuroradiologist to determine IPH location, presence of a vascular abnormality, and associated extraparenchymal hemorrhage. Diagnostic accuracy was measured comparing it to the available reference standards, which included conventional catheter angiogram (CCA), surgical macroscopic findings, and pathology results. Medical records were reviewed for risk factors and correlation with final diagnosis. MD CTA demonstrated an accuracy of 97.7%, with a sensitivity of 96.4% (95% CI 0.79-0.99) and a specificity of 100% (95% CI 0.74-0.99) for the detection of vascular abnormalities in young patients with IPH. Additionally, MD CTA had a PPV of 100%, and the NPV 93.8% in this population. Of the 43 patients included in the study, 28 patients (65%) had a causative vascular etiology for the IPH. Among the 28 patients with vascular etiologies for the IPH, 11 had an AVM (39.2%), nine a ruptured aneurysm (32.14%), seven dural venous sinus thrombosis (25%), and one had vasculitis (3.57%). MD CTA is highly accurate in the detection of vascular abnormalities in the setting of IPH, which as a group represents the most frequent etiology of IPH among patients age <or=40 years. MD CTA performed in the Emergency Department provides accurate, rapid and critical presurgical and premedical treatment information in young patients with IPH.

    Title Diagnostic Accuracy and Yield of Multidetector Ct Angiography in the Evaluation of Spontaneous Intraparenchymal Cerebral Hemorrhage.
    Date August 2009
    Journal Ajnr. American Journal of Neuroradiology
    Excerpt

    Multidetector CT angiography (MDCTA) is emerging as the favored initial diagnostic examination in the evaluation of patients presenting with spontaneous intraparenchymal hemorrhage (IPH). This study aims to evaluate the diagnostic accuracy and yield of MDCTA for the detection of vascular etiologies in adult patients presenting to the emergency department with IPH.

    Title Ct Angiography for Intracerebral Hemorrhage Does Not Increase Risk of Acute Nephropathy.
    Date July 2009
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    CT angiography (CTA) is receiving increased attention in intracerebral hemorrhage (ICH) for its role in ruling out vascular abnormalities and potentially predicting ongoing bleeding. Its use is limited by the concern for contrast induced nephropathy (CIN); however, the magnitude of this risk is not known.

    Title Contrast-enhanced Mr Angiography is Not More Accurate Than Unenhanced 2d Time-of-flight Mr Angiography for Determining > or = 70% Internal Carotid Artery Stenosis.
    Date June 2009
    Journal Ajnr. American Journal of Neuroradiology
    Excerpt

    Internal carotid artery (ICA) atheromatous disease is an important cause of ischemic stroke, and endarterectomy or stent placement is typically indicated for symptomatic patients with > or = 70% stenosis. Our purpose was to compare contrast-enhanced MR angiography (CE-MRA) with unenhanced 2D time-of-flight MR angiography (2D TOF MRA) in detecting hemodynamically significant ICA stenosis, by using CT angiography (CTA) as the reference standard.

    Title Chlamydomonas Constans and the Evolution of Plant Photoperiodic Signaling.
    Date June 2009
    Journal Current Biology : Cb
    Excerpt

    The circadian clock controls several important processes in plant development, including the phase transition from vegetative growth to flowering. In Arabidopsis thaliana, the circadian-regulated gene CONSTANS (CO) plays a central role in the photoperiodic control of the floral transition, one of the most conserved flowering responses among distantly related plants. CO is a member of a plant-specific family of transcription factors, and when it arose during the evolution of higher plants is unclear.

    Title Arterial Wall Enhancement Overlying Carotid Plaque on Ct Angiography Correlates with Symptoms in Patients with High Grade Stenosis.
    Date May 2009
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    The degree of internal carotid artery (ICA) stenosis is an established primary risk factor for embolic stroke. Recent publications suggest that inflammatory features may also play an important role. Our purpose was to correlate acute neurological symptoms with either carotid artery wall enhancement or plaque calcification, on axial CT angiographic source images (CTA-SI) of patients with severe (>or=70%) ICA stenosis.

    Title A Polymorphism in the Interleukin-10 Promoter Affects the Course of Disease in Patients with Clear-cell Renal Carcinoma.
    Date May 2009
    Journal Human Immunology
    Excerpt

    In the tumor microenvironment, interleukin (IL)-10 production has a pleiotropic ability to positively and negatively influence the function of innate and adaptive immunity against cancer. This study investigated whether IL-10 genetic polymorphisms that influence gene expression levels play a role in the risk and clinical course of clear-cell renal cell carcinoma (RCC). We analyzed the allelic and haplotype frequency formed by alleles at -1082(G/A), -819(C/T), and -592(C/A) of the IL-10 gene in RCC (n = 126) and healthy individuals (n = 176). The frequency of IL-10 polymorphic variants was similar between patients and controls. However, -1082 G/A IL-10 genotype showed a significant association with three prognostic indicators: advanced disease stage (p = 0.002), higher tumor size (p = 0.001), and presence of adenopathy (p = 0.006). Our results can be explained by the contradictory antitumor or pro-tumorigenic relationship between this molecule and cancer. Genotypes associated with high or low levels of IL-10 gene expression (GG or AA-1082 IL-10) were both associated with a more favorable course of the disease. We propose the hypothesis that the -1082 GA medium expression genotype confers a tumor-promoting phenotype, likely resulting from the immunosuppressive effects of anti-tumor Th-1 responses in conjunction with the insufficient inhibition of tumor angiogenesis at this intermediate level of IL-10 expression.

    Title Genetic Polymorphisms of Rantes, Il1-a, Mcp-1 and Tnf-a Genes in Patients with Prostate Cancer.
    Date February 2009
    Journal Bmc Cancer
    Excerpt

    Inflammation has been implicated as an etiological factor in several human cancers, including prostate cancer. Allelic variants of the genes involved in inflammatory pathways are logical candidates as genetic determinants of prostate cancer risk. The purpose of this study was to investigate whether single nucleotide polymorphisms of genes that lead to increased levels of pro-inflammatory cytokines and chemokines are associated with an increased prostate cancer risk.

    Title Imaging of the Carotid Arteries: the Role of Duplex Ultrasonography, Magnetic Resonance Arteriography, and Computerized Tomographic Arteriography.
    Date January 2009
    Journal Vascular Medicine (london, England)
    Excerpt

    Stenosis of the internal carotid artery represents a major cause of stroke, with atherosclerosis representing the major pathophysiology of this stenosis. It is estimated that over 700,000 Americans suffer a stroke annually. A prompt and accurate diagnosis of carotid artery disease is critical when planning a therapeutic strategy. Physical examination is inaccurate in determining the presence and severity of carotid artery disease. Therefore, reliable imaging tests which offer little risk to the patient are required.

    Title Case Records of the Massachusetts General Hospital. Case 34-2008. A 58-year-old Woman with Neck Pain and Fever.
    Date November 2008
    Journal The New England Journal of Medicine
    Title Spectroscopic Study of the Dispiro-1,2,4,5-tetroxane (cyclohexanone Diperoxide).
    Date October 2008
    Journal Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
    Excerpt

    The aim of this work is to present results derived from experimental IR and UV spectra and theoretical studies of DPCH, in order to get a more deeper insight on the physicochemical properties of this compound to gain a more deep knowledge of its action, helping in the design of new compounds with antimalaric effects. Experimental results are analyzed on the basis of theoretical calculations, which allow to derive suitable interpretations of spectral data.

    Title Analysis of Hla Class I Expression in Progressing and Regressing Metastatic Melanoma Lesions After Immunotherapy.
    Date September 2008
    Journal Immunogenetics
    Excerpt

    Despite the potential efficacy of cancer immunotherapy in preclinical studies, it did not show yet significant positive clinical results in humans with only a small number of cancer patients demonstrating objective tumor regression. This poor clinical outcome can be explained by the generation of sophisticated tumor immune escape mechanism, in particular, abnormalities in the expression of HLA class I antigens. We have studied the expression of HLA class I antigens in ten metastatic lesions obtained from a melanoma patient undergoing immunotherapy. Five lesions were obtained after Interferon-alpha-2b treatment and five after autologous vaccination plus BCG (M-VAX). Eight metastases were regressing after immunotherapy while two were progressing. The eight regressing metastases showed high level of HLA class I expression, whereas the two progressing lesions had low levels as measured by real time PCR and immunohistological techniques. These results indicate a strong association between HLA class I expression and progression or regression of the metastatic lesions. Our data support the hypothesis that the level of HLA class I expression is an important parameter of tumor immune escape that needs to be monitored.

    Title [portal and Mesenteric Vein Thrombosis Associated to a Prothrombin Gene Mutation]
    Date September 2008
    Journal Revista Española De Enfermedades Digestivas : Organo Oficial De La Sociedad Española De Patología Digestiva
    Title Evidence for Glycogenin Autoglucosylation Cessation by Inaccessibility of the Acquired Maltosaccharide.
    Date September 2008
    Journal Biochemical and Biophysical Research Communications
    Excerpt

    Glycogenin initiates the biosynthesis of proteoglycogen, the mammalian glycogenin-bound glycogen, by intramolecular autoglucosylation. The incubation of glycogenin with UDP-glucose results in formation of a tyrosine-bound maltosaccharide, reaching maximum polymerization degree of 13 glucose units at cessation of the reaction. No exhaustion of the substrate donor occurred at the autoglucosylation end and the full autoglucosylated enzyme continued catalytically active for transglucosylation of the alternative substrate dodecyl-maltose. Even the autoglucosylation cessation once glycogenin acquired a mature maltosaccharide moiety, proteoglycogen and glycogenin species ranging rM 47-200kDa, derived from proteoglycogen, showed to be autoglucosylable. The results describe for the first time the ability of polysaccharide-bound glycogenin for intramolecular autoglucosylation, providing evidence for cessation of the glucose polymerization initiated into the tyrosine residue, by inaccessibility of the acquired maltosaccharide moiety to further autoglucosylation.

    Title [factors Associated with Patient Satisfaction and Care of over 65 Year Olds in Emergency Departments]
    Date August 2008
    Journal Cirugía Española
    Excerpt

    INTRODUCTION: The population over 65 years old represents 40-50% of the all visits made to an emergency department (ED). Some situations of stress and dehumanization can occur due to user overflow. Our target is to identify factors influencing overall satisfaction of patients older than 65 attended in the ED, in order to identify points of conflict and improve the deficiencies in our care. MATERIAL AND METHOD: We performed a prospective study from September 2005-June 2006 with those patients who accepted to take part by filling an anonymous and confidential questionnaire. We evaluated 19 epidemiological variables, medical and related to the quality of information provided. A single bivariate analysis was performed (chi2, t-Student or logistic regression). RESULTS: The questionnaire was filled out by 1389 (31.3%) out of 4437 patients that could potentially be included in the study. Mean patient age was 77 +/- 6 years and more than half of them were women (64%). Of the responses, 82% rated their ED care as excellent or good. Variables significantly related to satisfaction were perception of a not-too-long waiting time (p = 0.001), having been attended to previously in the hospital (p = 0.050), having explained the tests that patients had to undergo (p = 0.002) and having been given clear information from staff (p = 0.001). CONCLUSIONS: In order to improve the quality of care given in the ED, the staff should give more personalized and clear information and reduce the patient perception that waiting time is too long.

    Title Evaluation of Functional Single Nucleotide Polymorphisms of Different Genes Coding for the Immunoregulatory Molecules in Patients with Monoclonal Large Granular Lymphocyte Lymphocytosis.
    Date July 2008
    Journal Human Immunology
    Excerpt

    TCR alpha beta+/CD4+ T-large granular lymphocyte (LGL) lymphocytosis is a subgroup of monoclonal T-LGL lymphoproliferative disorders that are different from the CD8+ TCR alpha beta T-LGL. An increasing evidence supports the involvement of a common antigen-driven mechanism in the etiology of TCR alpha beta+/CD4+ T-LGL. In this study, we tested several polymorphic markers associated with chronic viral infections and autoimmune diseases, including cytotoxic T-lymphocyte antigen-4 (CTLA-4), tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10), interferon-gamma (IFN-gamma), RANTES, IL-1 alpha, FAS, FAS-ligand (FASL), and NKG2D, to investigate the potential association of these immunogenetic factors with the development of T-LGL. Overall, 38 patients with CD4+ T-LGL were analyzed and compared with a group of both CD8+/TCR alpha beta+ T-LGL patients (n = 43) and a group of control subjects (n = 176). Our results did not show any clear association between the different single nucleotide polymorphisms (SNPs) analyzed and the development of CD4+/TCR alpha beta T-LGL. An increase in the frequency of -380 (AA/GA) TNF-alpha genotype associated with a greater production of this cytokine was found among CD8+ T LGL patients in comparison to the CD4+LGL patients and the control group. Our results suggest that the frequency of SNP of the genes coding for the studied immunoregulatory molecules are not associated with the development of CD4+/TCR alpha beta+ T-LGL.

    Title [arthroplasty After Failed Osteosynthesis in Hip Fractures]
    Date July 2008
    Journal Acta Ortopédica Mexicana
    Excerpt

    OBJECTIVE: To assess the functional status of patients with arthroplasty after failed osteosynthesis in hip fractures. MATERIAL AND METHODS: Prospective, descriptive, cohort of patients with primary failed osteosynthesis in hip fracture, who underwent total arthroplasty in the period 2002-2004, analyzed with the Harris functional scale. RESULTS: 26 patients: 17 women and 9 men, mean age of 74.8 years. Seventeen patients had loosening of dynamic hip screw, 5 of condylar screw 5 and 4 with cannulated screws. We made 12 hybrid, 10 cemented and 4 not cemented arthroplasties. Eighteen patients with good results, 7 with regular and 1 bad result. Patients with the highest rating were the youngest. DISCUSSION: Arthroplasty of the hip in a patient with failed osteosynthesis should be considered necessary. If we can improve pain of the hip, the patient will have less functional limitation and a better quality of life. This type of surgery requires high technical capability and experience by the orthopedic surgeon. CONCLUSIONS: Hip arthroplasty after failed osteosynthesis in hip fractures is a method that improves function and a gives a better life quality.

    Title Activity in Vitro of Twelve Antibiotics Against Clinical Isolates of Extended-spectrum Beta-lactamase Producing Escherichia Coli.
    Date January 2008
    Journal Journal of Basic Microbiology
    Excerpt

    Twelve beta-lactam and non-beta-lactam antibiotics were evaluated against 115 clinical isolates of extended-spectrum beta-lactamase-producing (ESBLs) Escherichia coli using a broth microdilution test in accordance with the CLSI guidelines. Susceptibility was 100% with imipenem, ertapenem and amikacin, 95.7% with piperacillin-tazobactam, 91.3% with cefoxitin, 87% with tobramycin, 81.7% with amoxicillin-clavulanate, 80% with cefepime, 67.8% with ceftazidime, 27.8% with ciprofloxacin, 27% with levofloxacin and 13% with ceftriaxone. Ertapenem was the antibiotic with the lowest minimum inhibitory concentrations (MICs) for all isolates. There were no clinically relevant differences in the activity of the antibiotics in the presence of CTX-M-9 or SHV enzymes.

    Title High Incidence of Ctla-4 Aa (ct60) Polymorphism in Renal Cell Cancer.
    Date October 2007
    Journal Human Immunology
    Excerpt

    Polymorphism in genes encoding T-cell regulatory proteins and cytokines may influence inflammation and cancer development via regulation of antitumor immune response. In the current study we analyzed genotypic frequencies of cytotoxic T-lymphocyte antigen-4 (CTLA-4)/CT60, CTLA-4/A49G, interleukin (IL)-4, and IL-10 polymorphisms in 117 renal cell carcinoma patients, 96 patients with colorectal cancer, and 196 healthy controls to test for an association between polymorphism in these genes and the risk of renal and colon cancer in a Spanish group of patients. In the case-control study, DNA samples from cancer patients and controls were analyzed using a TaqMan single nucleotide polymorphism genotyping assay. The distribution of IL-4 and IL-10 polymorphisms was similar between renal cancer patients and controls. However, a higher incidence of CTLA-4/CT60-AA genotype (p = 0.005; odds ratio (OR)= 2.12 with 95% confidence interval (CI): 1.28-3.50) and CTLA-4/A49G-AA (p = 0.022; OR = 1.76 with 95% CI: 1.11-2.80) genotype was observed in renal cancer patients than in controls. In addition, we observed a positive correlation between the AA genotype in both CTLA-4 polymorphisms and RCC grade, suggesting a role for the CTLA4 gene in tumor development. Therefore, our data suggest the CTLA-4 gene may be a candidate as a renal adenocarcinoma susceptibility gene, but does not play an important role in colon cancer.

    Title Regulatory Properties of Potato-arabidopsis Hybrid Adp-glucose Pyrophosphorylase.
    Date October 2007
    Journal Plant & Cell Physiology
    Excerpt

    In higher plants, ADP-glucose pyrophosphorylase (ADPGlc-PPase) is a heterotetrameric enzyme comprised of two small and two large subunits. Potato-Arabidopsis hybrid ADPGlc-PPases were generated and their regulatory properties analyzed. We show that ADPGlc-PPase subunits from two different species can interact, producing active enzymes with new regulatory properties. Depending on the subunit combinations, hybrid heterotetramers showed responses to allosteric effectors [3-phosphoglycerate (3-PGA) and Pi] in the micromolar or millimolar range. While hybrid potato small subunit (PSS) and the Arabidopsis large subunit APL1 showed an extremely sensitive response to 3-PGA and Pi, hybrid PSS/Arabidopsis APL2 was very insensitive to them. Intermediate responses were determined for other subunit combinations.

    Title Gene Transduction of an Active Mutant of Akt Exerts Cytoprotection and Reduces Graft Injury After Liver Transplantation.
    Date July 2007
    Journal American Journal of Transplantation : Official Journal of the American Society of Transplantation and the American Society of Transplant Surgeons
    Excerpt

    Akt is expected to be an effective target for the treatment of ischemia-reperfusion injury (I/R) due to its anti-apoptotic properties and its ability to activate the endothelial nitric oxide synthase (eNOS) enzyme. Therefore, this study was aimed to determine the efficacy of an active mutant of Akt (myr-Akt) to decrease I/R injury in a model of orthotopic liver transplantation in pigs. In addition, we analyzed the contribution of nitric oxide in the Akt-mediated effects by using an eNOS mutant (S1179DeNOS) that mimics the phosphorylation promoted by Akt in the eNOS sequence. Donors were treated with adenoviruses codifying for myr-Akt, S1179DeNOS or beta-galactosidase 24 h before liver harvesting. Then, liver grafts were orthotopically transplanted into their corresponding recipients. Levels of transaminases and lactate dehydrogenase (LDH) increased in all recipients after 24 h of transplant. However, transaminases and LDH levels were significantly lower in the myr-Akt group compared with vehicle. The percentage of apoptotic cells and the amount of activated-caspase 3 protein were also markedly reduced in myr-Akt-treated grafts after 4 days of liver transplant compared with vehicle and S1179DeNOS groups. In conclusion, myr-Akt gene therapy effectively exerts cytoprotection against hepatic I/R injury regardless of the Akt-dependent eNOS activation.

    Title Hla Class I Expression in Metastatic Melanoma Correlates with Tumor Development During Autologous Vaccination.
    Date June 2007
    Journal Cancer Immunology, Immunotherapy : Cii
    Excerpt

    Our knowledge of the mechanisms underlying tumor-specific immune response and tumor escape has considerably increased. HLA class I antigen defects remain an important tumor escape mechanism since they influence the interactions between tumor cells and specific T and NK cells in the course of malignant disease. We have studied here HLA class I expression in six subcutaneous metastases obtained from a melanoma patient immunized with an autologous melanoma cell vaccine (M-VAX). We report in this paper that HLA class I antigen expression on these metastatic lesions strongly correlated with the course of the disease. The three metastases that were partially regressing at the time of their excision showed a strong HLA class I expression, whereas the progressing ones showed a very weak or negative staining with most of the anti-HLA class I mAbs used. Real-time quantitative PCR of the samples obtained from microdissected tumor tissue revealed a significant difference in the mRNA levels of HLA-ABC heavy chain and beta2m between the two types of metastases, i.e., lower levels in progressing metastases and high levels in regressing ones, confirming the immunohistological findings. This is, to our knowledge, the first report where the clinical outcome of different HLA class I positive and negative melanoma metastases can be clearly correlated with the regression and progression of the disease, respectively.

    Title Case Records of the Massachusetts General Hospital. Case 14-2007. A 59-year-old Man with Fever and Pain and Swelling of Both Eyes and the Right Ear.
    Date May 2007
    Journal The New England Journal of Medicine
    Title Extracellular S-nitrosoglutathione, but Not S-nitrosocysteine or N(2)o(3), Mediates Protein S-nitrosation in Rat Spinal Cord Slices.
    Date January 2007
    Journal Journal of Neurochemistry
    Excerpt

    There is evidence that protein S-nitrosothiols (PrSNOs) accumulate in inflammatory demyelinating disorders like multiple sclerosis and experimental allergic encephalomyelitis. However, very little is known regarding the mechanism by which PrSNOs are formed in target cells. The present study compares the ability of potential intercellular mediators of nitrosative damage including S-nitrosoglutathione (GSNO), S-nitrosocysteine and N(2)O(3) to induce protein S-nitros(yl)ation in the spinal cord, a CNS region that is commonly affected in multiple sclerosis and experimental allergic encephalomyelitis. The results clearly demonstrate that while all three NO-donors cause S-nitrosation of proteins in cell-free systems, only GSNO is a viable S-nitrosating agent in rat spinal cord slices. Generation of PrSNOs with GSNO occurs by S-transnitrosation as the process was not inhibited by either the NO-scavenger rutin or the N(2)O(3)-scavenger azide. Contrary to other cell types, nerve cells incorporate intact GSNO and neither functional l-amino acid transporters nor cell-surface thiols are required. We also found that there is a restricted number of proteins available for S-nitrosation, even at high, non-physiological concentrations of GSNO. These proteins are highly concentrated in mitochondria and mitochondria-rich subcellular compartments. This study is relevant to those CNS disorders characterized by excessive nitric oxide production.

    Title Analysis of the Expression of Hla Class I, Proinflammatory Cytokines and Chemokines in Primary Tumors from Patients with Localized and Metastatic Renal Cell Carcinoma.
    Date January 2007
    Journal Tissue Antigens
    Excerpt

    Changes in the human leukocyte antigen (HLA) class I expression and cytokine and chemokine production both by cancer cells and by normal surrounding tissue are believed to be responsible for immune escape and tumor progression. In this study, we compared the tumor expression levels of HLA heavy chain (HLAhc), beta-2-microglobulin (beta2m), chemokines (Interferon-gamma-inducible Protein-10 (IP-10), Interferon-inducible T-cell Alpha-Chemoattractant (I-TAC), Stromal cell-Derived Factor-1 (SDF-1), Macrophage Inflammatory Protein-1-alpha (MIP-1-alpha) and Regulated upon Activation, Normally T-Expressed, and presumably Secreted (RANTES)) and cytokines (Vascular Endothelial Growth Factor (VEGF), Interferon-gamma (IFN-gamma), Interleukin-10 (IL-10), Tumor Growth Factor-beta (TGB-beta)) in primary tumors and adjacent normal tissues from patients with localized and metastatic renal cell carcinoma (RCC) using a quantitative real-time polymerase chain reaction technique. We report that the expression of HLAhc, beta2m and the studied cytokines and chemokines (except for SDF-1) was significantly higher in the tumor (29 samples) than in the normal tissue (14 samples). When we compared the tumor expression levels between patients with localized RCC and patients with advanced metastatic stage, we found that the messenger RNA expression levels of HLAhc and beta2m were much lower in patients with metastatic RCC (6 cases) than in patients with localized cancer (23 cases), with levels similar to those in normal tissue. This was also confirmed on a protein level by immunohistological labeling of tumor tissues. Thirty-nine percent of the analyzed RCC tumors showed partial loss of HLA class I molecules, while 6% of the tumors showed HLA class I total loss. The expression of IP-10, SDF-1 and VEGF-c was also significantly lower in patients with advanced tumor, while the IFN-gamma expression in metastatic RCC was not detectable. Our findings show that primary RCC tumors are characterized by a high expression of HLAhc and a presence of proinflammatory mediators and chemokines. We also observed that disease progression and development of metastasis in RCC are associated with decreased expression of HLAhc, beta2m, IP-10, SDF-1 and IFN-gamma. This microenvironment may suppress the cytotoxic response, creating conditions that favor tumor escape and cancer progression.

    Title Experimental Preparation and Uv/ir Spectroscopic Characterization of 1,3-dibutanal-1,2,4,5-tetroxane.
    Date January 2007
    Journal Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
    Excerpt

    We report the experimental preparation of the 1,3-butanal-1,2,4,5-tetroxane by oxidation of glutataldehyde with oxygen peroxide in presence of concentrated sulfuric acid, following the Bayer and Viller method modified by Jorge et al. The UV and IR spectra are studied from the experimental and theoretical standpoint. A rather complete vibrational assignment was performed and the nature of the electronic transitions was discussed in detail.

    Title Phylogenetic Analysis of a Biofilm Bacterial Population in a Water Pipeline in the Gulf of Mexico.
    Date November 2006
    Journal Fems Microbiology Ecology
    Excerpt

    The aim of this study was to assess the bacterial diversity associated with a corrosive biofilm in a steel pipeline from the Gulf of Mexico used to inject marine water into the oil reservoir. Several aerobic and heterotrophic bacteria were isolated and identified by 16S rRNA gene sequence analysis. Metagenomic DNA was also extracted to perform a denaturing gradient gel electrophoresis analysis of ribosomal genes and to construct a 16S rRNA gene metagenomic library. Denaturing gradient gel electrophoresis profiles and ribosomal libraries exhibited a limited bacterial diversity. Most of the species detected in the ribosomal library or isolated from the pipeline were assigned to Proteobacteria (Halomonas spp., Idiomarina spp., Marinobacter aquaeolei, Thalassospira sp., Silicibacter sp. and Chromohalobacter sp.) and Bacilli (Bacillus spp. and Exiguobacterium spp.). This is the first report that associates some of these bacteria with a corrosive biofilm. It is relevant that no sulfate-reducing bacteria were isolated or detected by a PCR-based method. The diversity and relative abundance of bacteria from water pipeline biofilms may contribute to an understanding of the complexity and mechanisms of metal corrosion during marine water injection in oil secondary recovery.

    Title Practical Noninvasive Neurovascular Imaging of the Neck Arteries in Patients with Stroke, Transient Ischemic Attack, and Suspected Arterial Disease That May Lead to Ischemia, Infarction, or Flow Abnormalities.
    Date October 2006
    Journal Seminars in Ultrasound, Ct, and Mr
    Excerpt

    Stroke is the third leading cause of death in the United States, killing nearly 157,000 people a year with an estimated society cost of dollar 58 billion in 2006. A large percentage of ischemic strokes is secondary to extracranial carotid and vertebral arterial disease. While digital subtraction angiography has traditionally been used for the initial evaluation of the degree of stenosis, noninvasive imaging has moved to the forefront in the extracranial arterial evaluation. The importance of understanding the imaging techniques, findings, interpretation, artifacts, and pitfalls is essential to appropriate patient management.

    Title Loh at 6p21.3 Region and Hla Class I Altered Phenotypes in Bladder Carcinomas.
    Date September 2006
    Journal Immunogenetics
    Excerpt

    Alterations in HLA class I antigen expression have been frequently described in different epithelial tumors and are thought to favor tumor immune escape from T lymphocyte recognition. Multiple molecular mechanisms are responsible for these altered HLA class I tumor phenotypes. Some are structural defects that produce unresponsiveness to treatment with interferons. Others include alterations in regulatory mechanisms that can be switched on by treatment of tumor cells with different cytokines. One important mechanism belonging to the first group is loss of heterozygosity (LOH) at chromosome region 6p21.3, which can lead to HLA haplotype loss. In this investigation, the frequency of LOH at 6p21 chromosome region was studied in 69 bladder carcinomas. Short tandem repeat analysis showed that 35% of cases had LOH in this chromosome region. By considering these results together with immunohistological findings previously published by our group, we identified a distribution pattern of HLA class I altered phenotypes in bladder cancer. The most frequently altered phenotype in bladder carcinomas was total loss of HLA class I expression (17 cases, 25%), followed by phenotype II associated with HLA haplotype loss (12 cases, 17.5%), and HLA allelic loss (ten cases, 14.5%). Nine cases (13%) were classified as having a compound phenotype, five cases (7%) as having HLA locus loss, and in 16 cases (23%) no alteration in HLA expression was detected. An important conclusion of this report is that a combination of different molecular and immunohistological techniques is required to precisely define which HLA alleles are lost during tumor progression and to characterize the underlying mechanisms of these losses. These studies should be performed when a cancer patient is to be included in an immunotherapy protocol that aims to stimulate different immune effector mechanisms.

    Title Characterization of Bacterial Community Associated to Biofilms of Corroded Oil Pipelines from the Southeast of Mexico.
    Date August 2006
    Journal Anaerobe
    Excerpt

    Microbial communities associated to biofilms promote corrosion of oil pipelines. The community structure of bacteria in the biofilm formed in oil pipelines is the basic knowledge to understand the complexity and mechanisms of metal corrosion. To assess bacterial diversity, biofilm samples were obtained from X52 steel coupons corroded after 40 days of exposure to normal operation and flow conditions. The biofilm samples were directly used to extract metagenomic DNA, which was used as template to amplify 16S ribosomal gene by PCR. The PCR products of 16S ribosomal gene were also employed as template for sulfate-reducing bacteria (SRB) specific nested-PCR and both PCR products were utilized for the construction of gene libraries. The V3 region of the 16S rRNA gene was also amplified to analyse the bacterial diversity by analysis of denaturing gradient gel electrophoresis (DGGE). Ribosomal library and DGGE profiles exhibited limited bacterial diversity, basically including Citrobacter spp., Enterobacter spp. and Halanaerobium spp. while Desulfovibrio alaskensis and a novel clade within the genus Desulfonatronovibrio were detected from the nested PCR library. The biofilm samples were also taken for the isolation of SRB. Desulfovibrio alaskensis and Desulfovibrio capillatus, as well as some strains related to Citrobacter were isolated. SRB consists in a very small proportion of the community and Desulfovibrio spp. were the relatively abundant groups among the SRB. This is the first study directly exploring bacterial diversity in corrosive biofilms associated to steel pipelines subjected to normal operation conditions.

    Title Modelling the Thermal Evolution of Enzyme-created Bubbles in Dna.
    Date August 2006
    Journal Journal of the Royal Society, Interface / the Royal Society
    Excerpt

    The formation of bubbles in nucleic acids (NAs) is fundamental in many biological processes such as DNA replication, recombination, telomere formation and nucleotide excision repair, as well as RNA transcription and splicing. These processes are carried out by assembled complexes with enzymes that separate selected regions of NAs. Within the frame of a nonlinear dynamics approach, we model the structure of the DNA duplex by a nonlinear network of coupled oscillators. We show that, in fact, from certain local structural distortions, there originate oscillating localized patterns, that is, radial and torsional breathers, which are associated with localized H-bond deformations, reminiscent of the replication bubble. We further study the temperature dependence of these oscillating bubbles. To this aim, the underlying nonlinear oscillator network of the DNA duplex is brought into contact with a heat bath using the Nosé-Hoover method. Special attention is paid to the stability of the oscillating bubbles under the imposed thermal perturbations. It is demonstrated that the radial and torsional breathers sustain the impact of thermal perturbations even at temperatures as high as room temperature. Generally, for non-zero temperature, the H-bond breathers move coherently along the double chain, whereas at T=0 standing radial and torsional breathers result.

    Title Comparison of the Sybr Green and the Hybridization Probe Format for Real-time Pcr Detection of Hhv-6.
    Date April 2006
    Journal Microbiological Research
    Excerpt

    A comparative study was conducted of a novel real-time quantitative PCR test (LightCycler System) with FastStart DNA Master(PLUS) SYBR Green I dye to detect DNA of human herpes virus 6 (HHV-6). Results were compared with those of a real-time quantitative PCR with hybridization probe (HP) formats using the fluorescence resonance energy transfer method, and with those of a single qualitative PCR test. The detection limit of the test with SYBR Green I dye was 20 copies of the virus, similar to that of the other two tests. The reproducibility was satisfactory. The new test has the same advantages as real-time PCR with HP formats and offers a greater versatility at lower cost.

    Title Ct Angiography Source Image Evaluation for Stroke.
    Date March 2006
    Journal Seminars in Ultrasound, Ct, and Mr
    Excerpt

    Computed tomography angiogram of the head and neck has lately become a pivotal imaging modality in the patient with acute stroke symptoms due to its high resolution, accuracy, speed, and sensitivity in the assessment of brain parenchyma and vascular patency.

    Title [cotard's Delusion of Negations]
    Date January 2006
    Journal Acta Médica Portuguesa
    Excerpt

    The authors report a clinical case of a sixty-two-year-old woman admitted to hospital because Cotard's nihilistic delusion in a one year major depressive episode. The patient was treated with clomipramine and olanzapine with a rapid improvement and normalisation of humor and delusions.

    Title Tc-99 Hmpao Labeled Leukocyte Imaging in a Renal Transplant in a Patient with Ulcerative Colitis.
    Date January 2006
    Journal Clinical Nuclear Medicine
    Title Calorimetric and Computational Study of Enthalpy of Formation of 3,6-dibutanoic-1,2,4,5-tetroxane.
    Date December 2005
    Journal Bioorganic & Medicinal Chemistry
    Excerpt

    A thermochemical a rather simple experimental technique method, is used to determine the enthalpy of the formation of 3,6-dibutanoic-1,2,4,5-tetroxane. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6-311G basis set level. Some possible extensions of the present procedure are pointed out.

    Title Noninvasive Evaluation of Carotid Artery Stenosis: Indications, Strategies, and Accuracy.
    Date November 2005
    Journal Neuroimaging Clinics of North America
    Excerpt

    Carotid artery occlusive disease is an important stroke risk factor and accounts for a significant proportion of stroke morbidity and mortality. In this article we survey the major clinical trials related to stroke risk in symptomatic and asymptomatic patients who have internal carotid artery (ICA) stenosis; techniques for noninvasive screening of ICA stenosis including ultrasound, MR angiography, and CT angiography; and evolving algorithms for ICA evaluation. We comment on current interest in plaque morphology as a risk factor for stroke.

    Title Differential Pattern of Expression and Sugar Regulation of Arabidopsis Thaliana Adp-glucose Pyrophosphorylase-encoding Genes.
    Date April 2005
    Journal The Journal of Biological Chemistry
    Excerpt

    ADP-glucose pyrophoshorylase (ADP-Glc PPase) catalyzes the first and limiting step in starch biosynthesis. In plants, the enzyme is composed of two types of subunits (small and large) and is allosterically regulated by 3-phosphoglycerate and phosphate. The pattern of expression and sugar regulation of the six Arabidopsis thaliana ADP-Glc PPase-encoding genes (two small subunits, ApS1 and ApS2; and four large subunits, ApL1-ApL4) has been studied. Based on mRNA expression, ApS1 is the main small subunit or catalytic isoform responsible for ADP-Glc PPase activity in all tissues of the plant. Large subunits play a regulatory role, and the data presented define a clear functional distinction among them. ApL1 is the main large subunit in source tissues, whereas ApL3 and, to a lesser extent, ApL4 are the main isoforms present in sink tissues. Thus, in source tissues, ADP-Glc PPase would be finely regulated by the 3-phosphoglycerate/phosphate ratio, whereas in sink tissues, the enzyme would be dependent on the availability of substrates for starch synthesis. Sugar regulation of ADP-Glc PPase genes is restricted to ApL3 and ApL4 in leaves. Sugar induction of ApL3 and ApL4 transcription in leaves allows the establishment of heterotetramers less sensitive to the allosteric effectors, resembling the situation in sink tissues. The results presented on the expression pattern and sugar regulation allow us to propose a gene evolution model for the Arabidopsis ADP-Glc PPase gene family.

    Title Coordinated Downregulation of the Antigen Presentation Machinery and Hla Class I/beta2-microglobulin Complex is Responsible for Hla-abc Loss in Bladder Cancer.
    Date January 2005
    Journal International Journal of Cancer. Journal International Du Cancer
    Excerpt

    Downregulation of MHC class I expression is a widespread phenomenon used by tumor cells to escape antitumor T-cell-mediated immune responses. These alterations may play a role in the clinical course of the disease. The aim of our study was to investigate the molecular mechanism underlying the absence of HLA-class I molecule expression in bladder cancer cells. Microdissected tumor tissues were characterized by real-time quantitative PCR for the expression of HLA-ABC, beta2-microglobulin and the members of the antigen processing machinery (APM) of HLA class I molecules (LMP2, LMP7, TAP1, TAP2 and tapasin). Our results showed that irreversible HLA loss by mutations in the beta2-microglobulin gene was not the cause of low HLA class I expression in bladder cancers. In contrast, we observed a coordinated transcription downregulation of HLA-ABC and beta2-microglobulin and APM genes in microdissected tumor tissue derived from bladder carcinomas. This mechanism may represent a major factor for the downregulation of HLA class I expression and in the subsequent direct recognition of cancer cells by cytolytic T lymphocytes. Because this regulatory mechanism is frequently reversible by IFN-gamma treatment, we conclude that HLA class I expression should be a major consideration for immunotherapeutic purposes in patients with bladder cancer.

    Title Phylogenetic Characterization of a Corrosive Consortium Isolated from a Sour Gas Pipeline.
    Date December 2004
    Journal Applied Microbiology and Biotechnology
    Excerpt

    Biocorrosion is a common problem in oil and gas industry facilities. Characterization of the microbial populations responsible for biocorrosion and the interactions between different microorganisms with metallic surfaces is required in order to implement efficient monitoring and control strategies. Denaturing gradient gel electrophoresis (DGGE) analysis was used to separate PCR products and sequence analysis revealed the bacterial composition of a consortium obtained from a sour gas pipeline in the Gulf of Mexico. Only one species of sulfate-reducing bacteria (SRB) was detected in this consortium. The rest of the population consisted of enteric bacteria with different characteristics and metabolic capabilities potentially related to biocorrosion. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. The low abundance of the detected SRB was evidenced by environmental scanning electron microscopy (ESEM). In addition, the localized corrosion of pipeline steel in the presence of the consortium was clearly observed by ESEM after removing the adhered bacteria.

    Title Conservative Treatment of Meibomian Gland Dysfunction.
    Date April 2004
    Journal Eye & Contact Lens
    Excerpt

    PURPOSE: To evaluate the effectiveness of lid hygiene and preservative-free artificial tears for the treatment of meibomian gland dysfunction (MGD) during a 6-week period. METHODS: Suitable patients with MGD were educated about their disease and instructed to begin a regimen of lid hygiene, which included the application of a heated saline solution and the use of nonpreserved artificial tears. Baseline measurements obtained at the time of enrollment included basic tear secretion test, tear breakup time, a questionnaire grading MGD symptoms (i.e., burning, irritation, itching, sharp pains, foreign body sensation, and hazy vision), and lid margin slitlamp photographs. All measurements except for basic tear secretion were repeated at the 6-week follow-up visit. Photographs were unlabeled, and two cornea specialists graded them in a masked fashion for the presence of lid erythema, irregularity, thickness, meibomian gland capping, and telangiectasis. RESULTS: Thirty-seven patients with a clinical diagnosis of MGD were enrolled, and 26 patients (70%) completed the study. Initial measurement of basic tear secretion averaged 17 mm and was more than 10 mm in 81% of eyes. The tear breakup time was prolonged by an average of 3.4 seconds; in 30% of cases, it was normalized to 10 seconds or more. Symptoms improved in 88% of cases; among those, symptoms were graded mild or less in 83%, and none in 39%. Photographs before and after treatment were not significantly different. CONCLUSIONS: In this noncontrolled case-cohort study of selected patients with MGD, lid hygiene and preservative-free artificial tears significantly improved tear breakup time and relieved symptoms of the condition.

    Title Flow Voids in Time-of-flight Mr Angiography of Carotid Artery Stenosis? It Depends on the Te!
    Date January 2004
    Journal Ajnr. American Journal of Neuroradiology
    Title Total Occlusion Versus Hairline Residual Lumen of the Internal Carotid Arteries: Accuracy of Single Section Helical Ct Angiography.
    Date October 2003
    Journal Ajnr. American Journal of Neuroradiology
    Excerpt

    BACKGROUND: AND PURPOSE: Routine carotid sonography and MR angiography cannot reliably detect the markedly reduced flow velocities associated with very severe carotid stenosis. In this study, we sought to evaluate the accuracy of single row detector helical CT angiography in distinguishing hairline residual lumen from total occlusion of severely stenosed internal carotid arteries (ICAs). METHODS: From our departmental data base of single row detector CT angiography studies performed for evaluation of ICA occlusive disease, 21 cases were identified with evidence of either hairline residual lumen or total occlusion on correlative conventional catheter radiographic arteriograms; these included seven cases of proved hairline residual lumen and 14 cases of proved total occlusion. Two neuroradiologists, blinded to the radiographic arteriography results, graded the diseased ICA on each CT angiogram as definitely occluded, probably occluded, indeterminate, probably patent, or definitely patent. Receiver operating characteristic curves were generated for each neuroradiologist. RESULTS: At an operating point on the receiver operating characteristic curve corresponding to 90% sensitivity, the first reader achieved 95% specificity and the second reader achieved 80% specificity for distinguishing hairline residual lumen from total occlusion. Absolute accuracy rates were 95% and 85%, respectively. No significant difference in accuracy was observed between the two readers (P =.28, two-tailed t test). CONCLUSION: Single row detector CT angiography can distinguish total ICA occlusion from hairline residual lumen with a high degree of accuracy. In equivocal cases, conventional catheter arteriography may be desirable to confirm the diagnosis.

    Title The Different Large Subunit Isoforms of Arabidopsis Thaliana Adp-glucose Pyrophosphorylase Confer Distinct Kinetic and Regulatory Properties to the Heterotetrameric Enzyme.
    Date September 2003
    Journal The Journal of Biological Chemistry
    Excerpt

    ADP-glucose pyrophosphorylase catalyzes the first and limiting step in starch biosynthesis and is allosterically regulated by the levels of 3-phosphoglycerate and phosphate in plants. ADP-glucose pyrophosphorylases from plants are heterotetramers composed of two types of subunits (small and large). In this study, the six Arabidopsis thaliana genes coding for ADP-glucose pyrophosphorylase isoforms (two small and four large subunits) have been cloned and expressed in an Escherichia coli mutant deficient in ADP-glucose pyrophosphorylase activity. The co-expression of the small subunit APS1 with the different Arabidopsis large subunits (APL1, APL2, APL3, and APL4) resulted in heterotetramers with different regulatory and kinetic properties. Heterotetramers composed of APS1 and APL1 showed the highest sensitivity to the allosteric effectors as well as the highest apparent affinity for the substrates (glucose-1-phosphate and ATP), whereas heterotetramers formed by APS1 and APL2 showed the lower response to allosteric effectors and the lower affinity for the substrates. No activity was detected for the second gene coding for a small subunit isoform (APS2) annotated in the Arabidopsis genome. This lack of activity is possibly due to the absence of essential amino acids involved in catalysis and/or in the binding of glucose-1-phosphate and 3-phosphoglycerate. Kinetic and regulatory properties of the different heterotetramers, together with sequence analysis has allowed us to make a distinction between sink and source enzymes, because the combination of different large subunits would provide a high plasticity to ADP-glucose pyrophosphorylase activity and regulation. This is the first experimental data concerning the role that all the ADP-glucose pyrophosphorylase isoforms play in a single plant species. This phenomenon could have an important role in vivo, because different large subunits would confer distinct regulatory properties to ADP-glucose pyrophosphorylase according to the necessities for starch synthesis in a given tissue.

    Title C-chain-bound Glycogenin is Released from Proteoglycogen by Isoamylase and is Able to Autoglucosylate.
    Date July 2003
    Journal Biochemical and Biophysical Research Communications
    Excerpt

    Proteoglycogen glycogenin is linked to the glucose residue of the C-chain reducing end of glycogen. We describe for the first time the release by isoamylase and isolation of C-chain-bound glycogenin (C-glycogenin) from proteoglycogen. The treatment of proteoglycogen with alpha-amylase releases monoglucosylated and diglucosylated glycogenin (a-glycogenin) which is able to autoglucosylate. It had been described that isoamylase splits the glucose-glycogenin linkage of fully autoglucosylated glycogenin previously digested with trypsin, releasing the maltosaccharide moiety. It was also described that carbohydrate-free apo-glycogenin shows higher mobility in SDS-PAGE and twice the autoglucosylation capacity of partly glucosylated glycogenin. On the contrary, we found that the C-glycogenin released from proteoglycogen by isoamylolysis shows lower mobility in SDS-PAGE and about half the autoglucosylation acceptor capacity of the partly glucosylated a-glycogenin. This behavior is consistent with the release of maltosaccharide-bound glycogenin instead of apo-glycogenin. No label was split from auto-[14C]glucosylated C-glycogenin or fully auto-[14C]glucosylated a-glycogenin subjected to isoamylolysis without previous trypsinolysis, thus proving no hydrolysis of the maltosaccharide-tyrosine linkage. The ability of C-glycogenin for autoglucosylation would indicate that the size of the C-chain is lower than the average length of the other glycogen chains.

    Title Oscillation of Mrna Level and Activity of Granule-bound Starch Synthase I in Arabidopsis Leaves During the Day/night Cycle.
    Date June 2003
    Journal Plant Molecular Biology
    Excerpt

    Granule-bound starch synthase (GBSSI) is one of the most extensively studied enzymes of the starch synthesis pathway and its role in the synthesis of amylose has been well established. However, few studies have been carried out to characterize the regulation of GBSSI gene. Regulation of starch synthesis genes is especially interesting in photosynthetic tissues, where starch is subjected to a periodical alternation of synthesis and degradation during the day/night cycle. In this report we show a circadian oscillation of GBSSI mRNA levels in leaves of Arabidopsis during the day/night cycle, and provide evidence that GBSSI expression is controlled by the transcription factors CCA1 and LHY. Over-expression of both CCA1 and LHY genes causes the elimination of GBSSI mRNA oscillation. Binding shift assays indicate that this control may be exerted through a direct interaction of those regulatory proteins with the GBSSI promoter. Oscillation is not observed on the GBSSI protein levels, which remains constant along the cycle. However, GBSSI activity shows a clear oscillation with a period of 24 h that is altered in transgenic plants over-expressing CCA1. Possible mechanisms controlling GBSSI activity during the day/night cycle are discussed.

    Title Diffusion Magnetic Resonance Imaging of Acute Ischemic Stroke.
    Date January 2003
    Journal Seminars in Roentgenology
    Title Perfusion Magnetic Resonance Imaging of Acute Ischemic Stroke.
    Date January 2003
    Journal Seminars in Roentgenology
    Title Us of Neurovascular Occlusive Disease: Interpretive Pearls and Pitfalls.
    Date December 2002
    Journal Radiographics : a Review Publication of the Radiological Society of North America, Inc
    Excerpt

    Ultrasonography (US) of the head and neck is a convenient but operator-dependent screening tool for detection and diagnosis of neurovascular occlusive disease. In US examination of the extracranial carotid arteries, stenosis is most commonly graded according to the peak systolic Doppler velocity in the region of maximal luminal narrowing rather than according to the percentage of atheromatous plaque occupying the lumen. However, the peak systolic velocity is not always reliable in estimation of the degree of stenosis. General diagnostic pitfalls include technical difficulties with scanning, failure to review the spectral waveform patterns, the presence of additional stenotic lesions, and anatomic variants. Specific examples of pitfalls include tandem lesions, differentiation of pseudo-occlusion from true total occlusion, pseudonormalization of velocities in cases of very severe stenosis, lesions of the carotid artery origin or aortic valve, progression of subclavian steal, underestimation of severe stenosis due to heavily calcified plaque, a persistent trigeminal artery, and contralateral carotid artery stenosis. Although conventional angiography remains the standard of reference for assessment of carotid artery disease, recognition of these common sources of error in US can improve the accuracy of this noninvasive test in diagnosis of carotid artery occlusion.

    Title Diffusion Mr Imaging of Acute Ischemic Stroke.
    Date October 2002
    Journal Neuroimaging Clinics of North America
    Excerpt

    Diffusion MR imaging provides unique information about the physiologic state of ischemic tissue. It is highly sensitive and specific in the detection of acute and hyperacute ischemic stroke and has greatly improved the diagnosis and treatment of acute stroke. The DWI abnormality provides information about clinical outcome and final infarct size. Diffusion combined with perfusion MR imaging provides information about the operational ischemic penumbra and final infarct size. Diffusion MR imaging seems to be promising in the evaluation of candidates for thrombolysis.

    Title Basilar and Middle Cerebral Artery Reserve: a Comparative Study Using Transcranial Doppler and Breath-holding Techniques.
    Date January 2002
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    BACKGROUND AND PURPOSE: A 1997 report suggests that the posterior circulation of the normal brain has diminished vasoreactivity compared with the anterior circulation. To further study this, we quantified and compared the vasodilatory capacities of the middle cerebral (MCA) and basilar artery (BA) territories in response to changes in PaCO(2), as indices of respective cerebrovascular reserve (CVR). If posterior circulation CVR is indeed physiologically lower than that of the MCA, it might indicate a greater risk of low-flow ischemia distal to basilar obstructive cerebrovascular lesions and provide a rationale for earlier treatment of such lesions with interventional techniques. We also wished to establish normal baseline CVR values for the posterior circulation. METHODS: Twelve patients with signs and/or symptoms suggestive of posterior circulation disease but without flow-limiting obstructive changes and 11 normal controls were entered into the study. With the use of transcranial Doppler techniques, alterations in blood flow velocity in response to sequential breath-holding trials of varying duration were simultaneously monitored in both MCAs and the BA. CVR was measured as the percent velocity increase (during breath-holding) from resting baseline values. RESULTS: No significant differences were found in CVR between the MCA and BA territories in or between patients and controls. CONCLUSIONS: Our study suggests that the anterior and posterior circulations have similar reserve capacities in individuals without flow-limiting cerebrovascular obstructive lesions and that the BA territory, relative to the MCA territory, is not at increased risk for low-flow stroke on the basis of limited reserve potential.

    Title Inactivation and Thermal Stabilization of Glycogenin by Linked Glycogen.
    Date December 2001
    Journal Biochemical and Biophysical Research Communications
    Excerpt

    Glycogen-free but not glycogen-bound glycogenin transglucosylates dodecyl-beta-maltoside. Furthermore, its sugar nucleotide-binding site can be photoaffinity labeled using [beta-(32)P]5-azido-UDP-glucose. Disruption with DMSO of the hydrogen bonds that stabilize the alpha-helical structure of glycogen restored the photoaffinity labeling of the glycogen-bound enzyme but not its transglucosylation activity. The larger size polysaccharide that linked to glycogenin allowed transglucosylation corresponding to that of PG-200, a proteoglycogen species of M(r) 200 kDa. PG-200 showed lower activity and increased activation energy than glycogen-free glycogenin. Heat denaturation of glycogen-free and glycogen-bound glycogenin occurred at 51 and 64 degrees C, respectively. Active glycogenin was recovered after the glycogen-bound form was heated at 60-70 degrees C and immediately cooled. Treatment at 60 degrees C of the glycogen-free enzyme resulted in inactivation. This is the first report describing the inactivation and thermal stabilization of an enzyme by linked polysaccharide.

    Title Three-dimensional Ultrasound for the Measurement of Choroidal Melanomas.
    Date September 2001
    Journal Archives of Ophthalmology
    Excerpt

    OBJECTIVE: To evaluate the reliability of 3-dimensional ultrasound (3D-US) for the measurement of choroidal melanomas. DESIGN: Retrospective case series. PARTICIPANTS: Forty-two consecutive cases of choroidal melanoma imaged with 3D-US. METHODS: Tumor measurements obtained with ophthalmoscopy, transillumination, standard ultrasound techniques, 3D-US, and pathological studies. Tumor diameters, heights, and volumes were compared. Our 3D-US tumor measurement techniques were tested for intraobserver and interscan reproducibility. RESULTS: Fifty 3D-US images were studied. The 3D-US tumor measurements were found to be reproducible (height coefficient of variation [CV] < or = 3%; diameter CV < or = 9.7%; volume CV < or = 13.2%). There was significant correlation with the usual methods of tumor measurement (diameter r = 0.76; height r > or = 0.98). Significant differences were found between measurements at pathological examination, as compared with both 2-dimensional and 3D-US height measurements (range, 0.73-0.83 mm). This finding was thought to be due to specimen shrinkage. Three-dimensional ultrasound was found to be at least as reproducible as clinical examination and standard ultrasound techniques used for measurement of diameter and height of choroidal melanomas. It was our impression that the 3D-US volume measurements accounted for the geometry of the tumor better than volume estimates calculated from basal area and tumor height. CONCLUSIONS: Three-dimensional ultrasound measurements of choroidal melanoma were reproducible, correlated well with other tumor measurement techniques, and can be used for measurement of choroidal melanomas.

    Title Complications and Re-operation Rate After Tension-band Wiring of Olecranon Fractures.
    Date November 2000
    Journal Journal of Orthopaedic Science : Official Journal of the Japanese Orthopaedic Association
    Excerpt

    Tension-band wire fixation of olecranon fractures leads to a high re-operation rate because of the need to remove the metalware. This problem has commonly been thought to be related mainly to the backing-out of the Kirschner wires. A retrospective study was carried out in 55 patients with displaced olecranon fractures operated on with the tension-band wiring technique, in whom there was an overall 71.7% re-operation rate. Complications were few and minor in most patients. The main reason for the removal of the metalware was a direct complaint from the patient (in 61.3% of all removals). A literature review analyzing the causes of metalware removal is also presented.

    Title Plaque-mounted Diode-light Transillumination for Localization Around Intraocular Tumors.
    Date March 1999
    Journal Archives of Ophthalmology
    Excerpt

    OBJECTIVE: To evaluate the usefulness of plaque-mounted diode-light transillumination (DLT) for the localization of episcleral plaques around intraocular tumors. METHODS: A clinical case series was performed to create, evaluate, and modify diode-light plaque construction, application, and imaging. Eight patients with choroidal melanoma were offered DLT as an additional method of ophthalmic plaque localization. Plaques were constructed by affixing non-heat-producing, light-emitting diodes with their apertures flush with the episcleral outer surface of the rim of the plaque. A bioimplantable epoxy was used to encapsulate the electronic components. Radioactive DLT eye plaques were sewn to the episclera to cover the base of the intraocular tumors; then diode lights were illuminated, viewed, and recorded. Thus, DLT was used to photographically document the relative position of the eye plaque covering the tumor base. The use of DLT also permitted a subjective evaluation of the contact (plaque contact) of each light with the sclera. RESULTS: Still and video images of plaque-mounted diode retro-transillumination were obtained, and no evidence of toxic effects of diode light were noted. CONCLUSIONS: Small posterior melanomas are difficult to visualize with standard transillumination techniques and are associated with poor local control. To improve and document plaque placement, we developed plaque-mounted diode lights for retrobulbar transillumination. This technique provides unique photographic documentation of episcleral plaque localization beneath intraocular tumors.

    Title Three-dimensional Ultrasonography of Choroidal Melanoma: Extrascleral Extension.
    Date December 1998
    Journal American Journal of Ophthalmology
    Excerpt

    PURPOSE: To describe the results of three-dimensional ultrasonography used to evaluate extrascleral extension of a choroidal melanoma. METHODS: Case report. The three-dimensional ultrasound system uses a 10-MHz B-mode transducer combined with a motorized rotating holder. The system acquires 180 sequential images that are stored and processed to create a three-dimensional block of the region of interest. RESULTS: Unique coronal and oblique perspectives were obtained from interactive manipulation of the three-dimensional reconstruction. Examination of the three-dimensional image allowed us to detect the transscleral uveal-orbital connection. Extrascleral melanomatous extension was confirmed on histopathologic examination. CONCLUSION: Three-dimensional ultrasonography is a promising imaging technique for evaluating melanomatous extrascleral extension.

    Title [neuroendocrine Carcinoma of the Larynx. Review of Literature in Reference to One Case Report]
    Date July 1998
    Journal Anales Otorrinolaringológicos Ibero-americanos
    Excerpt

    Neuroendocrin tumors are unusual neoplasies, even more within the ENT-sphere. Report of 1 case treated in our Service. Review of immunohistochemical criteria with the aim of achieving the diagnosis. Some bibliographical series are analyzed with the target to pick up the treatment of these uncommon growths.

    Title [cervical Metastasis of Choriocarcinoma]
    Date July 1998
    Journal Anales Otorrinolaringológicos Ibero-americanos
    Excerpt

    Neck metastatic adenopathy involves to set off a protocol aiming to specify the growth's origin. Complete ENT-examination facing a hard, movable, laterocervical lump is compulsory. Lacking the primary next comes fine needle biopsy and if it's not clear enough a cervicotomy must be performed. We report the diagnosis, the treatment and the follow-up of a testicle choriocarcinoma case, diagnosed through neck biopsy. Perusal of the bibliography.

    Title Salmonella Typhi Ty2 Ompc Porin Induces Bactericidal Activity on U937 Monocytes.
    Date April 1998
    Journal Microbiology and Immunology
    Excerpt

    The immunogenic effect of Salmonella typhi OmpC porin during typhoid fever in humans was evaluated in vitro. Peripheral blood mononuclear cells from 17 patients were challenged with outer membrane preparations from Escherichia coli UH302 and UH302/pSTP2K2 strains, both lacking E. coli OmpF and OmpC porins, although UH302/pSTP2K2 expressed a plasmid-encoded S. typhi Ty2 OmpC. The mononuclear cell supernatants, immunized in vitro with OmpC antigen, derived from 10 out of 17 patients activated U937 bactericidal capacity. In contrast, the supernatants from the immunization with outer membrane preparation lacking S. typhi Ty2 OmpC induced a significantly reduced bactericidal capacity of U937 cells. This procedure should prove useful for in vitro characterization of cellular immunogens from exclusive human pathogens.

    Title Three-dimensional Ultrasonography of Choroidal Melanoma: Localization of Radioactive Eye Plaques.
    Date March 1998
    Journal Archives of Ophthalmology
    Excerpt

    OBJECTIVE: To evaluate the use of 3-dimensional (3D) ultrasonography for the localization of episcleral eye plaques during the treatment of choroidal melanomas. METHODS: A series of 13 patients with choroidal melanoma were treated with radioactive palladium 103 seeds affixed into gold eye plaques. During surgery, 3D ultrasonography was performed with a commercially available system to evaluate the relative position of radioactive plaques secured beneath their intraocular tumors. This system consists of an automated, rotating, handheld, B-scan ultrasonographic probe operating at 10 MHz, a personal computer, and 3D imaging software. RESULTS: We measured the margins of the plaque extending beyond the tumor and the distance between the radioactive seeds and the tumor apex. We also evaluated the relationship between the plaque edge, the episclera, and the tumor's edges. While the plaques were well centered over the tumor in all cases, the plaque margins around the tumor were found to be variably sized. When comparing measurements taken at the time of plaque insertion with those taken at the time of plaque removal, we noted changes in the apical tumor height and in plaque centration. In the 1 patient with a juxtapapillary tumor, the posterior margin of the plaque was found to be displaced away from the sclera, or "tilted." CONCLUSIONS: Three-dimensional ultrasonography offers a new method for ophthalmic plaque localization. Unique perspectives can be visualized through the use of computer-aided 3D reconstructions that permit the assessment of the relative position of the plaque to the optic nerve and the measurement of the distance between the in vivo radioactive seed and the tumor apex. Our experience suggests that when compared with 2-dimensional ultrasonography, 3D ultrasonography offers new capabilities that can be used to improve plaque placement and radiation dose calculations.

    Title Biosynthesis of Proteoglycogen: Modulation of Glycogenin Expression in the Developing Chicken.
    Date December 1997
    Journal Biochemical and Biophysical Research Communications
    Excerpt

    Glycogenin, the autoglucosyltransferase that primes the biosynthesis of proteoglycogen, is found in the polysaccharide linked proteoglycogen form in mammals and chicken. Glycogenin was released from proteoglycogen and its activity was measured, together with that of glycogen synthase as well as glycogen content, in muscle, liver, and brain during chicken development. The specific activity of glycogenin, expressed per protein, increased with development only in muscle and was higher than the specific activities measured in liver and brain at any time. Concomitant with the rise in activity, an enhanced expression of the protein was observed with Western blot. The specific activity of glycogen synthase increased with development in muscle and liver, while glycogen accumulation was noticeable only in liver. The results indicate that the molar concentration of proteoglycogen is higher in muscle than in liver. The high glycogen content of liver may indicate that the size of the polysaccharide moiety of proteoglycogen is larger in liver than in muscle. This is the first report of developmental modulation of de novo biosynthesis of glycogen at the level of the primer that initiates glucose polymerization.

    Title [nutritional Status of Preschool Children in Ciudad De La Habana from 1972 to 1993]
    Date November 1997
    Journal Revista Panamericana De Salud Pública = Pan American Journal of Public Health
    Excerpt

    Two anthropometric surveys of children and adolescents have been carried out in Cuba with national samples. A third study done in the province of Ciudad de la Habana provided information on the physical characteristics of the population in that area and a baseline for the periodic evaluation of its nutritional status. This article compares the weight and height results obtained in these surveys for children 0 to 5 years old who lived in this province with the international reference standards proposed by WHO. The results show that, despite the economic difficulties the country has faced, the prevalence of malnutrition is low. In 1993, the prevalence of low height-for-age was 3.1%; that of low weight-for-height, 0.4%; and that of low weight-for-age, 1.5%. Overweight was the most common type of malnutrition, with a prevalence of 5.2%. Between 1972 and 1993, the prevalence of chronic malnutrition fell 32.6%, acute malnutrition was reduced by 69.2%; malnutrition of all types decreased by 44.4%; and overweight fell 48.5%.

    Title [anomalies of the First Branchial Cleft]
    Date May 1994
    Journal Anales Otorrinolaringológicos Ibero-americanos
    Excerpt

    Account of the case of a little girl of four and a half years brought to the consulting otologist because of her earache, otorrhoea, retroauricular inflammatory swelling and oedema of the external ear canal on left side. Frequency, evolution, diagnostic means and management measures for first branchial cleft are reviewed.

    Title An Investigation of Injection Techniques for Local Analgesia of the Equine Distal Tarsus and Proximal Metatarsus.
    Date February 1993
    Journal Equine Veterinary Journal
    Excerpt

    A positive radiographic contrast agent was injected into the tarsometatarsal (TMT) joints of both hindlimbs of 10 horses. Lateromedial radiographic views were obtained at 5, 15 and 30 mins after injection. Injection was successful in 19 of 20 limbs. Communication between the centrodistal (CD) and TMT joints was identified in 7 limbs (35%). Contrast agent extended around the tendons of tibialis cranialis (TC) and fibularis tertius (FT) in 18 limbs, and in 7 limbs some contrast entered the tarsal sheath. Slight to moderate plantar and/or distal extension of contrast agent was identified in 13 limbs. On a subsequent occasion positive contrast agent was injected subtarsally using one of two techniques and radiography was repeated. Contrast agent was principally distributed on the plantar aspect of the 3rd metatarsal bone, the plantar aspect of the suspensory ligament and between the superficial and deep digital flexor tendons. Extension of contrast agent into the TMT joint was identified in only 1 limb but in 8 limbs contrast agent extended into the tarsal sheath. The practical implications of these results include the possibility that local anaesthetic solution injected into the TMT joint may alleviate pain from the CD joint, the insertions of TC and FT or the tarsal sheath. It may also result in perineural analgesia of the dorsal metatarsal nerves or the plantar metatarsal nerves. In some cases subtarsal injection of local anaesthetic solution may result in alleviation of pain from the tarsal sheath. False negative results for subtarsal analgesia may be achieved by inadvertent injection into the tarsal sheath or into a blood or lymphatic vessel.

    Title Floricaula: a Homeotic Gene Required for Flower Development in Antirrhinum Majus.
    Date January 1991
    Journal Cell
    Excerpt

    Plants carrying the floricaula (flo) mutation cannot make the transition from inflorescence to floral meristems and have indeterminate shoots in place of flowers. The flo-613 allele carries a Tam3 transposon insertion, which allowed the isolation of the flo locus. The flo gene encodes a putative protein (FLO) containing a proline-rich N-terminus and a highly acidic region. In situ hybridization shows that the flo gene is transiently expressed in the very early stages of flower development. The earliest expression seen is in bract primordia, followed by sepal, petal, and carpel primordia, but no expression is detected in stamen primordia. This pattern of expression has implications for how flo affects phyllotaxis, organ identity, and determinacy. We propose that flo interacts in a sequential manner with other homeotic genes affecting floral organ identity.

    Title Determination of Intracellular Nitrate.
    Date June 1989
    Journal The Biochemical Journal
    Excerpt

    A sensitive procedure has been developed for the determination of intracellular nitrate. The method includes: (i) preparation of cell lysates in 2 M-H3PO4 after separation of cells from the outer medium by rapid centrifugation through a layer of silicone oil, and (ii) subsequent nitrate analysis by ion-exchange h.p.l.c. with, as mobile phase, a solution containing 50 mM-H3PO4 and 2% (v/v) tetrahydrofuran, adjusted to pH 1.9 with NaOH. The determination of nitrate is subjected to interference by chloride and sulphate when present in the samples at high concentrations. Nitrite also interferes, but it is easily eliminated by treatment of the samples with sulphamic acid. The method has been successfully applied to the study of nitrate transport in the unicellular cyanobacterium Anacystis nidulans.

    Title Relationship Between a 47-kda Cytoplasmic Membrane Polypeptide and Nitrate Transport in Anacystis Nidulans.
    Date February 1989
    Journal Biochemical and Biophysical Research Communications
    Excerpt

    The polypeptide composition of cytoplasmic membranes of the cyanobacterium Anacystis nidulans changes in response to variations in the nitrogen source available to the cells, differing specifically in the amount of a polypeptide of 47-kDa molecular mass. Synthesis of the polypeptide and expression of nitrate transport activity are repressed by ammonium. Transfer of ammonium-grown cells to a medium containing nitrate as the sole nitrogen source results in parallel development of the 47-kDa polypeptide and nitrate transport activity of the cells. These results suggest the involvement of the 47-kDa cytoplasmic membrane polypeptide in nitrate transport by A. nidulans.

    Title [pericarditis Caused by Q Fever. Presentation of a Case]
    Date February 1988
    Journal Revista Clínica Española
    Title Regulated Nitrate Transport in the Cyanobacterium Anacystis Nidulans.
    Date October 1987
    Journal Journal of Bacteriology
    Excerpt

    Intracellular accumulation of nitrate, indicative of the operation of an active nitrate transport system, has been measured in intact cells of the cyanobacterium Anacystis nidulans. The ability of the cells to accumulate nitrate was effectively hindered by either ammonium addition or selective inhibition of CO2 fixation by DL-glyceraldehyde, with the effect of either compound being prevented by previously blocking ammonium assimilation. The results support the contention that nitrate utilization in cyanobacteria is regulated at the level of nitrate transport through the concerted action of ammonium assimilation and CO2 fixation.

    Title Modulation of Nitrate Uptake in Anacystis Nidulans by the Balance Between Ammonium Assimilation and Co2 Fixation.
    Date September 1987
    Journal Archives of Biochemistry and Biophysics
    Excerpt

    Gradual inhibition of ammonium assimilation in Anacystis nidulans cells by increasing concentrations of 5-hydroxylysine resulted in a progressive enhancement of nitrate uptake. For 5-hydroxylysine-treated cells, the magnitude of the inhibition of nitrate uptake promoted by added ammonium was dependent on the ammonium assimilation capacity. In cells with a moderate ammonium assimilation activity, acceleration of CO2 fixation induced by bicarbonate addition antagonized the negative effect of ammonium, allowing full nitrate uptake activity. The results support the contention that nitrate utilization is under the feed-back control exerted by products of its own assimilation via ammonium, the inhibitory effect being potentiated by ammonium addition and alleviated by enhanced CO2 fixation. Results of amino acid analysis in cells exhibiting different capacities to utilize nitrate speak against these compounds as direct effectors of nitrate uptake.

    Title Inhibition of Nitrate Utilization by Amino Acids in Intact Anacystis Nidulans Cells.
    Date September 1985
    Journal Archives of Microbiology
    Excerpt

    In an attempt to establish the nature of the ammonium-assimilation products which mediate the inhibition by ammonium of nitrate uptake in cyanobacteria, the effect of different amino acids on nitrate utilization by intact Anacystis nidulans cells has been assayed. To exclude an indirect inhibition of nitrate uptake through the ammonium which the amino acids might release, the cells were pretreated with L-methionine-D,L-sulfoximine (MSX), a potent inactivator of glutamine synthetase. Under these conditions, several L-amino acids, but not the corresponding D-isomers, affected nitrate utilization to a variable extent, causing inhibitions ranging between 20 and 80% when added at 20 mM concentration. For most of the inhibitory amino acids, including L-isoleucine, L-leucine and L-valine, a correlation was found between their ability to act as amino group donors to alpha-ketoglutarate, in reactions catalyzed by A. nidulans cell-free extracts, and their inhibitory effect on nitrate utilization. L-Glutamine, L-asparagine and glycine, being effective inhibitors of nitrate utilization, were poor substrates for the transaminating activity to alpha-ketoglutarate, however. The possible role of the latter amino acids as mediators in the ammonium-promoted inhibition of nitrate uptake is discussed.

    Title Dependence of Nitrate Utilization Upon Active Co2 Fixation in Anacystis Nidulans: a Regulatory Aspect of the Interaction Between Photosynthetic Carbon and Nitrogen Metabolism.
    Date April 1985
    Journal Archives of Biochemistry and Biophysics
    Excerpt

    Specific inhibition of photosynthetic CO2 fixation in Anacystis nidulans cells by D,L-glyceraldehyde resulted in the simultaneous inhibition of nitrate utilization, indicating a dependence of the latter process upon the provision of CO2-fixation products. This dependence was lost in cells treated with L-methionine-D,L-sulfoximine or azaserine, effective inhibitors of ammonium assimilation. In these cells, nitrate uptake could proceed at rates similar to those in control cells even if CO2 fixation was severely inhibited by D,L-glyceraldehyde. The results support the contention that CO2-fixation products participate in the control of nitrate uptake in A. nidulans by preventing the accumulation of certain ammonium derivatives which are negative effectors of nitrate uptake.

    Title Bioelectrical Tissue Resistance During Various Methods of Myocardial Preservation.
    Date September 1983
    Journal The Annals of Thoracic Surgery
    Excerpt

    Twenty-one mongrel dogs underwent cardiopulmonary bypass (CPB) and ischemic cardiac arrest for 60 minutes. The bioelectrical tissue impedance, water content, and ultrastructure of the myocardium were studied and correlated with various types of myocardial protection applied. The animals were divided into three groups according to the myocardial protection applied: Group 1, moderate general hypothermia; Group 2, moderate general and local hypothermia; Group 3, moderate general hypothermia and crystalloid cardioplegia. The hearts from 3 normal dogs served as controls. After 35 minutes of ischemic arrest, the difference in bioelectrical impedance of the myocardium of the left ventricle between Groups 1 and 2 was highly significant (p less than 0.001); in Groups 2 and 3, a significant difference was observed after 50 minutes. The heart water content in all three groups increased over that found in the hearts of the control animals, but there was no significant difference between Groups 2 and 3. There was evidence by ultramicroscopic study of ischemic damage to the myocardium in all of the experimental groups. Damage was less evident in Groups 2 and 3. We conclude that measurement of myocardial bioelectrical tissue resistance is a sensitive indicator of myocardial damage due to ischemia and may be useful clinically in determining the need for and type of cardiac resuscitation, particularly following CPB.

    Title [comparative Evaluation of Prostate Size by Transabdominal Echography, Urethral Profile and Radiology (author's Transl)]
    Date May 1981
    Journal Journal D'urologie
    Excerpt

    Disappointed by the approximate assessment of prostate size given by traditional methods (rectal examination, endovesical filling defect produced by the hypertrophic organ in the secretory cystogram, length of the prostatic urethra by micturating urethrography), the authors carried out a prospective study in 100 patients undergoing surgery for benign prostatic hypertrophy which compared traditional data with those provided by transabdominal prostatic echography and the measurement of urethral manometric profile. Determination of the maximum dimensions of the adenoma was used to calculate its volume and weight. Ultrasound studies gave the most accurate information : 95% correct results. This was followed by the measurement of urethral profile with 81% of accurate results (but this is an instrumental procedure which has certain disadvantages). Radiology takes 3rd place, with 59% accurate results and rectal examination immediately after with 58%.

    Title [accidental Pollution of the Estuary of La Coruna by Mercury Compounds and Their Evolution]
    Date January 1976
    Journal Revista De Sanidad E Higiene Pública
    Title [air Pollution in Madrid in 1969]
    Date March 1971
    Journal Revista De Sanidad E Higiene Pública
    Title [conization]
    Date October 1970
    Journal Revista De Obstetricia Y Ginecología De Venezuela
    Title [air Pollution in Madrid in 1967]
    Date June 1969
    Journal Revista De Sanidad E Higiene Pública
    Title Expression of the Granule-bound Starch Synthase I (waxy) Gene from Snapdragon is Developmentally and Circadian Clock Regulated
    Date
    Journal Plant Physiology
    Excerpt

    The granule-bound starch synthase I (GBSSI or waxy) enzyme catalyzes one of the enzymatic steps of starch synthesis. This enzyme is responsible for the synthesis of amylose and is also involved in building the final structure of amylopectin. Little is known about expression of GBSSI genes in tissues other than storage organs, such as seeds, endosperm, and tuber. We have isolated a gene encoding the GBSSI from snapdragon (Antirrhinum majus). This gene is present as a single copy in the snapdragon genome. There is a precise spatial and developmental regulation of its expression in flowers. GBSSI expression was observed in all floral whorls at early developmental stages, but it was restricted to carpel before anthesis. These results give new insights into the role of starch in later reproductive events such as seed filling. In leaves the mRNA level of GBSSI is regulated by an endogenous circadian clock, indicating that the transition from day to night may be accompanied by abolition of expression of starch synthesis genes. This mechanism does not operate in sink tissues such as roots when grown in the dark.

    Title Characterisation and Expression Studies of a Root Cdna Encoding for Ferredoxin-nitrite Reductase from Lotus Japonicus.
    Date
    Journal Physiologia Plantarum
    Excerpt

    A full-length cDNA encoding for ferredoxin-nitrite reductase (NiR, EC 1.7.7.1), has been isolated from a root cDNA library from the legume Lotus japonicus and characterised. The NiR gene (Nii) is present as a single copy in this plant, and encodes a protein of 582 amino acids. The Lotus NiR protein is synthesised as a precursor with an amino-terminal transit peptide consisting of 25 amino acid residues. Sequence comparisons with leaf NiRs from different plant species and with other related redox proteins identified in the root NiR the same highly conserved residues involved in the cofactor binding than previously reported for leaves. Besides, a putative binding site for ferredoxin was also found in the N-terminal region of the protein. The NiR gene is expressed in roots and leaves, although the level of expression is much higher in roots, in accordance with the fact that L. japonicus assimilates nitrate mainly in roots. NiR mRNA, protein and activity are induced by nitrate in roots and leaves, while ammonium-grown plants only showed basal levels. No oscillations of NiR mRNA, protein and activity were observed during the day/night cycle, neither in roots nor leaves, making an interesting difference with rhythms observed in other plant species.

    Title Isolation of Photorespiratory Mutants from Lotus Japonicus Deficient in Glutamine Synthetase.
    Date
    Journal Physiologia Plantarum
    Excerpt

    A mutagenesis programme using ethyl methanesulphonate (EMS) was carried out on Lotus japonicus (Regel) Larsen cv. Gifu in order to isolate photorespiratory mutants in this model legume. These mutants were able to grow in a CO2-enriched atmosphere [0.7% (v/v) CO2] but showed stress symptoms when transferred to air. Among them, three mutants displayed low levels of glutamine synthetase (GS; EC 6.3.1.2) activity in leaves. The mutants accumulated ammonium in leaves upon transfer from 0.7% (v/v) CO2 to air. F1 plants of back crosses to wild type were viable in air and F2 populations segregated 3 : 1 (viable in air : air-sensitive) indicative of a single Mendelian recessive trait. Complementation tests showed that the three mutants obtained were allelic. Chromatography on DEAE-Sephacel used to separate the cytosolic and plastidic GS isoenzymes together with immunological data showed that: (1) mutants were specifically affected in the plastidic GS isoform, and (2) in L. japonicus the plastidic GS isoform eluted at lower ionic strength than the cytosolic isoform, contrary to what happens in most plants. The plastidic GS isoform present in roots of wild type L. japonicus was also absent in roots of the mutants, indicating that this plastidic isoform from roots was encoded by the same gene than the GS isoform expressed in leaf tissue. Viability of mutant plants in high-CO2 conditions indicates that plastidic GS is not essentially required for primary ammonium assimilation. Nevertheless, mutant plants did not grow as well as wild type plants in high-CO2 conditions.

    Title Distinctive Light and Co(2)-fixation Requirements of Nitrate and Ammonium Utilization by the Cyanobacterium Anacystis Nidulans.
    Date
    Journal Plant Physiology
    Excerpt

    The effect of light intensity on the rates of ammonium and nitrate uptake and of CO(2) fixation has been determined in intact Anacystis nidulans cells. Ammonium uptake became saturated at photon flux values of about 60 microeinsteins per square meter per second, whereas both nitrate uptake and CO(2) fixation reached saturation at about 250 microeinsteins per square meter per second, the rates of the two latter processes being tightly correlated at any light intensity assayed. Inhibition of ammonium assimilation resulted in the loss of correlation between CO(2) fixation and nitrate uptake, the latter process exhibiting then a reduced light requirement. The results establish a clear distinction between ammonium utilization and nitrate utilization with regard to their light requirement and to the nature of their dependence upon CO(2) fixation.

    Title Photosynthetic Assimilation of No(3) by Intact Cells of the Cyanobacterium Anacystis Nidulans: Influence of No(3) and Nh(4) Assimilation on Co(2) Fixation.
    Date
    Journal Plant Physiology
    Excerpt

    Illuminated suspensions of Anacystis nidulans, supplied with saturating concentrations of CO(2) evolved O(2) at a greater rate when nitrate was simultaneously present. The extent of the stimulation of noncyclic electron flow induced by nitrate was dependent on light intensity, being maximal under light saturating conditions. Accordingly, nitrate depressed the rate of CO(2) fixation at limiting but not at saturating light, this depression reflecting the competition between both processes for assimilatory power. In contrast, ammonium stimulated CO(2) fixation at any light intensity assayed, the stimulation being dependent on the incorporation of ammonium to carbon skeletons. The positive effect of ammonium on CO(2) fixation also appeared to occur when nitrate was the nitrogen source, since with either nitrogen source an increase in the incorporation of newly fixed carbon into acid-soluble metabolites took place. From these results, the in vivo partitioning of assimilatory power between photosynthetic nitrogen and carbon assimilation and the quantitative and qualitative effects of inorganic nitrogen assimilation on CO(2) fixation are discussed.

    Title Changes in Net O(2) Exchange Induced by Inorganic Nitrogen in the Blue-green Alga Anacystis Nidulans.
    Date
    Journal Plant Physiology
    Excerpt

    The response of net O(2) exchange to light intensity by intact Anacystis nidulans cells in the presence of saturating NaHCO(3) concentrations followed a curve with an inflection near the light-compensation point. Addition of either KNO(3) or NH(4)Cl stimulated O(2) uptake in the dark and at light intensities below the light-compensation point. This resulted in steeper slopes of the curve calculated below and above the light-compensation point. At O(2) concentrations limiting dark respiration, addition of inorganic nitrogen had no effect on either dark respiration or O(2) exchange in the light. The apparent changes in photosynthetic yield observed under normal O(2) concentration disappeared when respiration was limited by O(2) availability, indicating that the effects of inorganic nitrogen on O(2) exchange at low light intensities are due to stimulation of respiration rather than to increases in photosynthetic yield.

    Title Two Arabidopsis Adp-glucose Pyrophosphorylase Large Subunits (apl1 and Apl2) Are Catalytic.
    Date
    Journal Plant Physiology
    Excerpt

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (alpha(2)beta(2)) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1-APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta.

    Title [dynamic Hip Screw Vs. Percutaneous Compression Plate for Trochanteric Fractures]
    Date
    Journal Acta Ortopédica Mexicana
    Excerpt

    OBJECTIVE: To compare functional results, hemorrhage, wound infection, post-operative complications and implant stability in 31A1 and 31A2 fractures treated with percutaneous compression plate or dynamic hip screw. MATERIAL AND METHODS: We made a cuasi-experimental, longitudinal, prospective and comparative study in a period from December 2004 to February 2005. Statistical analysis: System SPSS version 11.0, with t Student, Xi square and U Mann-Whitney, with alpha 0.05. RESULTS: We included 26 patients with AO 31A1 and 31A2 fractures, 13 treated with percutaneous compression plate and 13 with dynamic hip screw. We did not found significant statistical difference in post-operative hospital stay; wound length, post-operative complications and consolidation time. There were no infection or other wound complications in either group. Time of surgery and hemorrhage were better in the percutaneous compression plate group (p < or = 0.05). CONCLUSIONS: Percutaneous compression plate offers similar functional results compared to the dynamic hip screw, with advantages in hemorrhage during surgery and after surgery, less surgery time, with less need of transfusions post-operatively.

    Title Ct Angiography-source Image Hypoattenuation Predicts Clinical Outcome in Posterior Circulation Strokes Treated With Intra-arterial Therapy.
    Date
    Journal Stroke; a Journal of Cerebral Circulation
    Excerpt

    BACKGROUND AND PURPOSE: The aim of this study was to correlate CT angiography-source image (CTA-SI) parenchymal hypoattenuation with clinical outcome in patients with vertebrobasilar occlusion treated with intra-arterial thrombolysis. METHODS: In 16 patients with vertebrobasilar occlusion treated with intra-arterial thrombolysis, we graded CTA-SI parenchymal hypoattenuation in the medulla, pons, midbrain, thalamus, cerebellum, occipital lobe, inferior parietal lobe, and medial temporal lobe. The grading scale was: 0, no hypoattenuation; 1, <50% hypoattenuation; and 2, >50% hypoattenuation. On CTA, we assessed clot location and length and collaterals. Outcome was measured with modified Rankin score. RESULTS: Mean patient age was 68.3 years (range, 47 to 86 years), National Institutes of Health Stroke Scale was 28 (range, 11 to 40), time to CTA was 5.2 hours (range, 0.69 to 15.32), and time from CTA to intra-arterial thrombolysis was 5 hours (range, 2.25 to 10.38 hours). There were 4 basilar, 2 vertebral, and 10 combined occlusions. Eleven patients had near complete, 4 had partial, and one had no recanalization. Independent outcome predictors measured as modified Rankin score at 3 months were CTA-SI pons and midbrain scores(cumulative r=0.81, P<0.001). For outcome dichotomized into death versus survival, the CTA-SI pons score (P=0.0037) was the only independent predictor. CONCLUSIONS: Hypoattenuation in the pons and midbrain on pretreatment CTA-SI correlates highly with clinical outcome in patients with vertebrobasilar occlusion treated with intra-arterial thrombolysis.

    Title The Role of Metabolic Memory in the Atp Paradox and Energy Homeostasis.
    Date
    Journal The Febs Journal
    Excerpt

    In yeast, a sudden transition from glucose limitation to glucose excess leads to a new steady state at increased metabolic fluxes with a sustained decrease in the ATP concentration. Although this behaviour has been rationalized as an adaptive metabolic strategy, the mechanism behind it remains unclear. Nevertheless, it is thought that, on glucose addition, a metabolite derived from glycolysis may up-regulate ATP-consuming reactions. The adenine nucleotides themselves have been ruled out as the signals that mediate this regulation. This is mainly because, in that case, it would be expected that the new steady state at increased fluxes would be accompanied by an increased stationary ATP concentration. In this study, we present a core model consisting of a monocyclic interconvertible enzyme system. Using a supply-demand approach, we demonstrate that this system can account for the empirical observations without involving metabolites other than the adenine nucleotides as effectors. Moreover, memory is an emerging property of such a system, which may allow the cell to sense both the current energy status and the direction of the changes.

    Title Intracellular Glutathione Mediates the Denitrosylation of Protein Nitrosothiols in the Rat Spinal Cord.
    Date
    Journal Journal of Neuroscience Research
    Excerpt

    Protein S-nitrosothiols (PrSNOs) have been implicated in the pathophysiology of neuroinflammatory and neurodegenerative disorders. Although the metabolically instability of PrSNOs is well known, there is little understanding of the factors involved in the cleavage of S-NO linkage in intact cells. To address this issue, we conducted chase experiments in spinal cord slices incubated with S-nitrosoglutathione (GSNO). The results show that removal of GSNO leads to a rapid disappearance of PrSNOs (t((1/2)) approximately 2 hr), which is greatly accelerated when glutathione (GSH) levels are raised with the permeable analogue GSH ethyl ester. Moreover, PrSNOs are stable in the presence of the GSH depletor diethyl maleate, indicating that GSH is critical for protein denitrosylation. Inhibition of GSH-dependent enzymes (glutathione S-transferase, glutathione peroxidase, and glutaredoxin) and enzymes that could mediate denitrosylation (alcohol dehydrogense-III, thioredoxin and protein disulfide isomerase) do not alter the rate of PrSNO decomposition. These findings and the lack of protein glutathionylation during the chase indicate that most proteins are denitrosylated via rapid transnitrosylation with GSH. The differences in the denitrosylation rate of individual proteins suggest the existence of additional structural factors in this process. This study is relevant to our recent discovery that PrSNOs accumulate in the central nervous system of patients with multiple sclerosis. (c) 2008 Wiley-Liss, Inc.

    Title Uptake of Lead and Its Influence in the Alga Selenastrum Capricornutum Printz.
    Date
    Journal Talanta
    Excerpt

    The influence of nutrient level, hours of fight and the flux of air by volume of solution on uptake of lead has been examined from batch growth experiments carried out with the alga Selenastrum capricornutum Printz. The organic matter released by the alga has been characterized in terms of absorbance at 285 nm, dissolved organic carbon and maximum intensity of fluorescence at the excitation peak. The lability of lead complexes formed with the alga exudates has been investigated in terms of differential pulse anodic stripping voltammetry (DPASV). It has been noticed that lead inhibits the division of the cells which become bigger in size but with less pigment per cell.

    Title Independent Validation of the Secondary Intracerebral Hemorrhage Score with Catheter Angiography and Findings of Emergent Hematoma Evacuation.
    Date
    Journal Neurosurgery
    Excerpt

    The secondary intracerebral hemorrhage (SICH) score, derived from a cohort of patients with intracerebral hemorrhage examined with computed tomographic (CT) angiography, predicts a patient's risk of harboring a vascular etiology.

    Title Ct Angiography Spot Sign Predicts In-hospital Mortality in Patients with Secondary Intracerebral Hemorrhage.
    Date
    Journal Journal of Neurointerventional Surgery
    Excerpt

    Background and objectiveThe presence of active contrast extravasation during CT angiography, the spot sign, is a potent predictor of in-hospital mortality in patients with primary intracerebral hemorrhage (ICH). However, its predictive value in patients with ICH due to a vascular abnormality, secondary ICH (SICH), is unknown. The aim of this study was to determine the clinical and radiological predictors of a spot sign and in-hospital mortality in patients with SICH.MethodsTwo experienced readers independently reviewed CT angiograms performed on 215 consecutive patients presenting to the emergency department with SICH over a 10-year period to assess the presence of spot signs according to strict radiological criteria. Differences in reader interpretation were resolved by consensus. Medical records were reviewed for baseline clinical characteristics and in-hospital mortality. Univariate and multivariate logistic regression analyses were performed to determine the clinical and radiological predictors of a spot sign and in-hospital mortality in patients with SICH.ResultsSpot signs were identified in 31 of 215 patients with SICH (14.4%), four of which were delayed spot signs (12.9%). Spot signs were most common in patients with arteriovenous fistulas (42%), Moyamoya (40%), elevated admission blood glucose (23%) and large intraventricular hemorrhage volumes (29%). Spot signs were most predictive of in-hospital mortality in patients with aneurysms of the anterior cerebral artery (100%) and anterior communicating artery (75%). In univariate analysis, the presence of a spot sign significantly increased the risk of in-hospital mortality in patients with SICH (38.7%, OR 2.2, 95% CI 1.0 to 4.9, p=0.0497). However, in multivariate logistic regression analysis the admission Glasgow Coma Scale was the only independent predictor of in-hospital mortality in patients with SICH (OR 2.8, 95% CI 1.6 to 5.1, p=0.0004).ConclusionThe spot sign identifies patients with SICH at increased risk of in-hospital mortality. However, the admission Glasgow Coma Scale was the only independent predictor of in-hospital mortality in this cohort of patients with SICH.

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