Surgical Specialist, Cardiothoracic Surgeons
18 years of experience
Video profile
2 Good Samaritan Way
Suite 220
Mount Vernon, IL 62864
618-899-3900
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Education ?

Medical School Score
University of Oklahoma (1992)
  • Currently 2 of 4 apples

Awards & Distinctions ?

Associations
American Board of Thoracic Surgery

Affiliations ?

Dr. Nguyen is affiliated with 3 hospitals.

Hospital Affilations

  • St John's Medical Center
  • Sacred Heart Medical Center - Riverbend 7/7/2006 Active Current Cardiovascular Thora
  • Sacred Heart Medical Center - University Dist 8/10/2008 Educational Current Cardiovascular Thora
  • Publications & Research

    Dr. Nguyen has contributed to 36 publications.
    Title Massless Dirac Fermions in a Graphene Superlattice: a T-matrix Approach.
    Date August 2011
    Journal Journal of Physics. Condensed Matter : an Institute of Physics Journal
    Excerpt

    Using the T-matrix approach, we study the effect of a Kronig-Penney periodic potential on the electronic states and the transport properties of graphene. The energy band structure and the group velocity of charge carriers are calculated and discussed in detail for potentials with varying amplitudes and barrier-to-well width ratios. The periodic potential is shown to cause a resonant structure and to enhance the magnitude of the conductivity.

    Title Regulation of the Biosynthesis of the Macrolide Antibiotic Spiramycin in Streptomyces Ambofaciens.
    Date November 2010
    Journal Journal of Bacteriology
    Excerpt

    Streptomyces ambofaciens synthesizes the macrolide antibiotic spiramycin. The biosynthetic gene cluster for spiramycin has been characterized for S. ambofaciens. In addition to the regulatory gene srmR (srm22), previously identified (M. Geistlich et al., Mol. Microbiol. 6:2019-2029, 1992), three putative regulatory genes had been identified by sequence analysis. Gene expression analysis and gene inactivation experiments showed that only one of these three genes, srm40, plays a major role in the regulation of spiramycin biosynthesis. The disruption of srm22 or srm40 eliminated spiramycin production while their overexpression increased spiramycin production. Expression analysis was performed by reverse transcription-PCR (RT-PCR) for all the genes of the cluster in the wild-type strain and in the srm22 (srmR) and srm40 deletion mutants. The results from the expression analysis, together with the ones from the complementation experiments, indicated that Srm22 is required for srm40 expression, Srm40 being a pathway-specific activator that controls most, if not all, of the spiramycin biosynthetic genes.

    Title A Field-programmable Gate Array Based System for High Frame Rate Laser Doppler Blood Flow Imaging.
    Date October 2010
    Journal Journal of Medical Engineering & Technology
    Excerpt

    This paper presents a general embedded processing system implemented in a field-programmable gate array providing high frame rate and high accuracy for a laser Doppler blood flow imaging system. The proposed system can achieve a basic frame rate of flow images at 1 frame/second for 256 x 256 images with 1024 fast Fourier transform (FFT) points used in the processing algorithm. Mixed fixed-floating point calculations are utilized to achieve high accuracy but with a reasonable resource usage. The implementation has a root mean square deviation of the relative difference in flow values below 0.1% when compared with a double-precision floating point implementation. The system can contain from one or more processing units to obtain the required frame rate and accuracy. The performance of the system is significantly higher than other methods reported to date. Furthermore, a dedicated field-programmable gate array (FPGA) board has been designed to test the proposed processing system. The board is linked with a laser line scanning system, which uses a 64 x 1 photodetector array. Test results with various operating parameters show that the performance of the new system is better, in terms of noise and imaging speed, than has been previously achieved.

    Title Multiple Routes of Hepatitis C Virus Transmission Among Injection Drug Users in Hai Phong, Northern Vietnam.
    Date September 2010
    Journal Journal of Medical Virology
    Excerpt

    To identify hepatitis C virus (HCV) transmission routes among injection drug users in Northern Vietnam, plasma samples were collected from 486 drug users in Hai Phong. Plasma viral RNA was extracted from 323 (66.5%) samples that were positive for anti-HCV antibodies. Portions of the HCV 5'-untranslated (5'UTR)-Core and NS5B genes were amplified by reverse-transcriptase polymerase chain reaction, sequenced directly, and genotyped in 194 and 195 specimens, respectively. Both regions were genotyped in 137 specimens. In the 5'UTR-Core region, genotype 6a was predominant (32.5%), followed by genotype 1a (23.7%), genotype 1b (20.6%), and genotype 6e (14.4%). In the NS5B region, genotype 1a was predominant (42.6%), followed by genotype 1b (24.1%), genotype 6a (14.4%), genotype 3b (7.2%), and genotype 6e (5.1%). Of the 137 specimens with both regions genotyped, 23 (16.8%) showed discordant genotyping results between the two regions, suggesting possible recombination and/or dual infection. Phylogenetic analysis revealed close associations between Hai Phong strains and strains from Southern China: the Yunnan province for genotype 3b; the Guangxi province for genotype 6e; the USA for genotype 1a; and Southern Vietnam for genotypes 1a and 6e. The human immunodeficiency virus (HIV) infection rate among HCV-infected injection drug users was 52.6-55.4% and did not differ significantly by HCV genotype. Most drug users infected with HIV-1 [98.8% (171/173)] were co-infected with HCV. These results suggest multiple routes of HCV transmission among injection drug users in Northern Vietnam that may also be HIV transmission routes.

    Title Glycosylation Steps During Spiramycin Biosynthesis in Streptomyces Ambofaciens: Involvement of Three Glycosyltransferases and Their Interplay with Two Auxiliary Proteins.
    Date September 2010
    Journal Antimicrobial Agents and Chemotherapy
    Excerpt

    Streptomyces ambofaciens synthesizes spiramycin, a 16-membered macrolide antibiotic used in human medicine. The spiramycin molecule consists of a polyketide lactone ring (platenolide) synthesized by a type I polyketide synthase, to which three deoxyhexoses (mycaminose, forosamine, and mycarose) are attached successively in this order. These sugars are essential to the antibacterial activity of spiramycin. We previously identified four genes in the spiramycin biosynthetic gene cluster predicted to encode glycosyltransferases. We individually deleted each of these four genes and showed that three of them were required for spiramycin biosynthesis. The role of each of the three glycosyltransferases in spiramycin biosynthesis was determined by identifying the biosynthetic intermediates accumulated by the corresponding mutant strains. This led to the identification of the glycosyltransferase responsible for the attachment of each of the three sugars. Moreover, two genes encoding putative glycosyltransferase auxiliary proteins were also identified in the spiramycin biosynthetic gene cluster. When these two genes were deleted, one of them was found to be dispensable for spiramycin biosynthesis. However, analysis of the biosynthetic intermediates accumulated by mutant strains devoid of each of the auxiliary proteins (or of both of them), together with complementation experiments, revealed the interplay of glycosyltransferases with the auxiliary proteins. One of the auxiliary proteins interacted efficiently with the two glycosyltransferases transferring mycaminose and forosamine while the other auxiliary protein interacted only with the mycaminosyltransferase.

    Title Effect of the Supporting Electrolyte Anion on the Thickness of Pss/pah Multilayer Films and on Their Permeability to an Electroactive Probe.
    Date March 2009
    Journal Langmuir : the Acs Journal of Surfaces and Colloids
    Excerpt

    Quartz crystal microbalance and cyclic voltammetry are used to investigate the influence of the supporting salt of polyelectrolyte solutions on the buildup and the structure of PSS/PAH polyelectrolyte multilayers (PSS: poly(4-styrene sulfonate); PAH: poly(allylamine hydrochloride)). This film constitutes a model polyelectrolyte multilayer system. The supporting electrolytes were sodium salts where the nature of the anion was changed by following the Hofmeister series from cosmotropic to chaotropic anions (F-, Cl-, NO3-, ClO4-). For all the investigated anions, the film thickness increases linearly with the number of deposition steps.Wefind that chaotropic anions lead to larger thickness increments per bilayer during the film buildup than cosmotropic ones, confirming results found on PSS/PDADMA multilayers (PDADMA:poly(diallyldimethylammonium)). Films constituted by more than nine PSS/PAH bilayers are still permeable to hexacyanoferrate(II) ions, Fe(CN)(6)4-, whatever the nature of the supporting salt anion. On the other hand, these films are impermeable to ruthenium(II) hexamine ions, Ru(NH3)(6)2+, after the third PAH layer in the presence of NaF, NaCl, or NaNO3. These results are explained by the presence of an excess of positive charges in the film, which leads to a positive Donnan potential. We find that this potential is more positive when more chaotropic anions are used during the film buildup. We also find that a film constructed in the presence of chaotropic anions swells and becomes more permeable to Fe(CN)(6)4- ions when the film is brought into contact with a solution containing more cosmotropic anions. All our experimental findings can be explained by a strong interaction between chaotropic anions with the NH3+groups of PAH that is equivalent, as far as the multilayer buildup and electrochemical response is concerned, to a deprotonation of PAH as it is observed when the film is constructed at a higher pH. We thus arrive to a coherent explanation of the effect of the nature of the anions of the supporting electrolyte on the polyelectrolyte multilayer. We also find that great care must be taken when investigating polyelectrolyte multilayer films by electrochemical probing because electrochemical reactions involving the probes can appreciably modify the multilayer structure.

    Title Spontaneous Coronary Dissection in Late Pregnancy: a Multidisciplinary Approach to Management.
    Date May 2008
    Journal The Annals of Thoracic Surgery
    Excerpt

    Spontaneous coronary dissection is a rare but potentially life-threatening condition. It often occurs in late pregnancy and may pose significant risks for the patient and the fetus. Its cause remains uncertain, and established guidelines for management have not been developed. In this report, close multidisciplinary collaboration has led to excellent outcomes in this condition.

    Title Ultrasound Assisted Synthesis of 5,9-dimethylpentadecane and 5,9-dimethylhexadecane--the Sex Pheromones of Leucoptera Coffeella.
    Date December 2007
    Journal Molecules (basel, Switzerland)
    Excerpt

    Racemic 5,9-dimethylpentadecane and 5,9-dimethylhexadecane, the major and minor constituents, respectively, of the sex pheromone of Leucoptera coffeella, have been synthesized from citronellol in 56-58% overall yield through six steps. Ultrasound irradiation efficiently supported tosylation of alcohols (two steps) as well as the subsequent cross coupling reactions with the pertinent Grignard reagents (also two steps).

    Title Transscalene Brachial Plexus Block: a New Posterolateral Approach for Brachial Plexus Block.
    Date September 2007
    Journal Anesthesia and Analgesia
    Excerpt

    Depending on the approach to the upper brachial plexus, severe complications have been reported. We describe a novel posterolateral approach for brachial plexus block which, from an anatomical and theoretical point of view, seems to offer advantages. Twenty-seven patients were scheduled to undergo elective major surgery of the upper arm or shoulder using this new transscalene brachial plexus block. The success rate was 85.2% for surgery. Two patients required additional analgesia with IV sufentanil. In two others, regional anesthesia was inadequate. The side effects of this technique included reversible recurrent laryngeal nerve blockade in two patients and a reversible Horner syndrome in one patient. Further studies are needed to compare the transscalene brachial plexus block with other approaches to the brachial plexus.

    Title Clinical Features of Hiv/aids Patients Presenting to an Inner City Clinic in Ho Chi Minh City, Vietnam.
    Date August 2007
    Journal International Journal of Std & Aids
    Excerpt

    An outpatient HIV clinic was opened in March 2005 in Binh Thanh District, a poor section of Ho Chi Minh City, Vietnam. Over 1500 patients were seen in the first year. The average age of patients was 27 years. Men represented 77% of the clinic population, women, 23% and children under the age of 16 years of age, 5% of the population. The most common risk factor among men was being an injecting drug user (IDU), 76%, and among women, being married to an IDU HIV-positive man, 35%. Physical signs of disease were uncommon: lymphadenopathy in 24% and hepatomegaly and splenomegaly in 4% and 3%, respectively. Men and women were anaemic at presentation, with a mean haemoglobin of 11.9 g/dL and 11.1 g/dL, respectively. An overwhelming majority of patients had profound immunodeficiency. The mean CD4+ cell count was 164 cells/mL and the median was 69 cells/mL. No correlation was found between the World Health Organization's stage of disease and the CD4+ cell count. Thus, the former is a poor predictor of immunity in this population. Data regarding opportunistic infections diagnosed at the first visit were studied. Candidiasis of the oral pharynx, oesophagus or vagina was found in 34.5% of the patients, and pulmonary and extrapulmonary tuberculosis was found in 32% of the patients. Pneumocystis carinii pneumonia (PCP) was diagnosed in only 3% of the patients. Cotrimoxazole prophylaxis is advocated for HIV-infected Vietnamese, but the incidence of PCP is negligible and resources could be spent elsewhere. The various opportunistic infections seen in this resource-poor clinic setting is likely to be a pattern of presentation of HIV-infected Vietnamese for some time to come.

    Title Transverse Characterization of High Air-fill Fraction Tapered Photonic Crystal Fiber.
    Date August 2005
    Journal Applied Optics
    Excerpt

    We demonstrate tapering of a high air-fill fraction photonic crystal fiber by using the flame-brushing technique. Transverse probing along the taper allows us to ascertain how the microstructure is preserved during tapering. Experimental results are compared with numerical simulations performed with the finite-difference time-domain and plane-wave expansion methods. Through this investigation we find that the fiber geometry is well preserved throughout the tapering process and we resolve the apparent discrepancies between simulation and experiment that arise through the finite extent of the fiber microstructure.

    Title Leakage of the Fundamental Mode in Photonic Crystal Fiber Tapers.
    Date July 2005
    Journal Optics Letters
    Excerpt

    We report detailed measurements of the optical properties of tapered photonic crystal fibers (PCFs). We observe a striking long-wavelength loss as the fiber diameter is reduced, despite the minimal airhole collapse along the taper. We associate this loss with a transition of the fundamental core mode as the fiber dimensions contract: At wavelengths shorter than this transition wavelength, the core mode is strongly confined in the fiber microstructure, whereas at longer wavelengths the mode expands beyond the microstructure and couples out to higher-order modes. These experimental results are discussed in the context of the so-called fundamental mode cutoff described by Kuhlmey et al. [Opt. Express 10, 1285 (2002)], which apply to PCFs with a finite microstructure.

    Title Coronary Blood Flow Assessment After Successful Angioplasty for Acute Myocardial Infarction Predicts the Risk of Long-term Cardiac Events.
    Date June 2005
    Journal Circulation
    Excerpt

    BACKGROUND: Analysis of coronary flow velocity (CFV) in the recanalized infarct-related coronary artery (IRA) with a Doppler guidewire is useful for predicting recovery of regional left ventricular function, in-hospital complications, and survival. We postulated that the CFV pattern after IRA reperfusion for acute myocardial infarction (AMI) would predict long-term adverse cardiac events. METHODS AND RESULTS: Sixty-eight consecutive patients with a first AMI underwent CFV measurement with a Doppler guidewire after successful reopening of the IRA by coronary angioplasty. At the end of follow-up, 3.8+/-1.7 years after AMI, 44 of the 65 surviving patients (67.7%) were free of long-term cardiac events. Univariate analysis showed that the following factors were predictive of an end point combining cardiac death, recurrent MI, and congestive heart failure: hypertension, age > or =65 years, time from onset of chest pain to PTCA > or =6 hours, peak creatine kinase >4000 IU/L, ejection fraction < or =50%, proximal left anterior descending artery occlusion, resting average peak velocity < or =10 cm/s, average systolic peak velocity < or =5 cm/s, a rapid diastolic deceleration time (< or =600 ms), and early retrograde systolic flow. In the final multivariate model, only age > or =65 years (OR, 3.6; 95% CI, 1.1 to 11.8; P=0.03), time to PTCA > or =6 hours (OR, 2.9; 95% CI, 1.0 to 8.3; P=0.04), and a rapid diastolic deceleration time (OR, 5.4; 95% CI, 1.5 to 19.3; P=0.01) were independent predictors. CONCLUSIONS: The CFV pattern appears to be an accurate predictor of long-term cardiac events in patients having undergone successful reopening of the IRA after AMI, identifying a subset of at-risk patients.

    Title Using Cartilage to Repair Bone: an Alternative Approach in Tissue Engineering.
    Date October 2004
    Journal Annals of Biomedical Engineering
    Excerpt

    Materials and techniques currently used for bone replacement/repair conform to the current paradigm, relying on bone or bone products to produce bone or induce bone formation. Yet, nature forms and heals most of the skeleton by ossification of a cartilaginous model. In this study, we cultured aggregates of E10.5 or E12 mouse embryonic limb cells in the bioreactor for 3 weeks, determined the stages of cartilage differentiation attained, and assessed the ossification and bone healing potential of the spheroids by implantation adjacent to, or directly in, a skull defect. Cultured spheroids had large cartilaginous areas, sometimes with cellular arrangements characteristic of growth plate zones. Aggregates implanted for 2 weeks adjacent to a defect mineralized and ossified (histology, micro-CT). Defects with implants had a central mass of differentiated and differentiating bone, with osteoclast activity, filling the defect. Controls had considerable remodeling on the bone edges demarcating the still present defect. This study shows that cartilage, grown in the bioreactor for 3 weeks, ossified when implanted adjacent to a bone defect, and when implanted directly in a defect, contributed to its healing. Our ability to grow differentiated bone-forming cartilage for implantation is an alternative approach in the field of bone repair.

    Title [cryptococosis and Hiv/aids: a Review of 21 Cases Reported in the Tropical Diseases Centre, Ho Chi Minh City (vietnam)]
    Date April 2004
    Journal Santé (montrouge, France)
    Excerpt

    Cryptococcus neoformans affections during HIV-infection are frequent and serious. The aim of this study was to analyse the epidemiological, clinical, biological and therapeutic characteristics of cryptococcal meningitis in HIV-positive patients, admitted into the Center for Tropical Diseases Ho Chi Minh City (Vietnam), during a 5-month period (May-September 2001). Twenty-one patients (20 men and one woman) were included (identification of C. neoformans from the cerebrospinal fluid). The mean age was 28 years. The majority of patients had been living in Ho Chi Minh City (48%). The use of drugs and unprotected sexual relations were the principal risk factors of HIV-infection. The paucity and the confusion of clinical signs and symptoms, along with a high frequency of meningitis have been analysed. Clinical presentation features included: headache (95%), emaciation (90%), oro-pharyngeal candidiasis (90%), stiff neck (80%), nausea/vomiting (70%), fever (67%), coughing (38%), diarrhoea (33%), skin lesions (5%), convulsion (5%), photophobia (5%), and hemiparesis (5%). The severity of the prognosis was mainly linked to the delay before hospitalization, to the possible association with other opportunistic infections, and to the availability of appropriate treatment.

    Title [penicillium Marneffei Infection and Aids. A Review of 12 Cases Reported in the Tropical Diseases Centre, Ho Chi Minh City (vietnam)]
    Date February 2004
    Journal Santé (montrouge, France)
    Excerpt

    Penicillium marneffei is a thermal dimorphic fungus which is endemic in an ecologic niche restricted to the Far East and which may cause deep-seated infection in humans and rodents. Discovered in the late 1950s from the bamboo rat Rhizomys sinensis, in Vietnam, P. marneffei was initially identified in HIV-infected individuals. A disseminated and progressive infection, it is the third most common opportunistic morbidity in the late course of HIV infection. We report the clinical and therapeutic features of a series of 12 HIV-infected adults with disseminated P. marneffei infection in Vietnam. From May to September, 2001, 12 patients with P. marneffei infection confirmed by culture were identified among 273 HIV-infected patients studied at the Tropical Diseases Centre, Ho Chi Minh City, Vietnam. The clinical signs were related to the reticuloendothelial system involvement. Common clinical features included fever, cutaneous manifestations, lymphadenopathy, hepatomegaly, splenomegaly, and marked anemia. The organism was identified from skin specimens or blood culture. Cases were consistently found with low CD4 (+) cell count. Treatment with parenteral amphotericin B and itraconazole was relatively effective, although treatment with a delaying diagnosis remained associated with pejorative prognosis.

    Title Percutaneous Nephrolithotomy in the Management of Complex Upper Urinary Tract Calculi: the Singapore General Hospital Experience.
    Date January 2003
    Journal Annals of the Academy of Medicine, Singapore
    Excerpt

    INTRODUCTION AND OBJECTIVES: Presently, percutaneous nephrolithotomy (PCNL) is a well-established and effective method of treating upper urinary tract stones at our institution. The aim of this paper was to evaluate a single surgeon's four-year experience of PCNL in the Singapore General Hospital. MATERIALS AND METHODS: Between January 1996 and December 2000, 300 PCNLs were performed on 280 renal units. The mean age was 53.7 years. PCNL was performed on 57 complete staghorn calculi (20.4%), 83 partial staghorn calculi (29.6%), 66 large pelvic calculi (23.6%), 60 impacted uretero-pelvic junction (UPJ) and upper ureteric stones (21.4%) that failed extracorporeal shock wave lithotripsy (ESWL) and 14 symptomatic lower pole calculi (5%). RESULTS: The stone-free rate on discharge was 88.2% (n = 247). At 3 months and 1-year post PCNL, the stone-free rate was 91.1% (n = 255) and 95.7% (n = 268), respectively. The average postoperative stay was 4.5 days. Complications included 1 urosepsis post-PCNL (0.4%) and 2 arterio-venous fistulae (0.7%). Only 1 patient (0.4%) required blood transfusion. Thirty-four patients (12.1%) required ESWL and 4 needed ureteroscopy (1.3%). CONCLUSION: In experienced hands, the use of PCNL for upper urinary tract calculi is safe and effective.

    Title Off-loading the Diabetic Foot Wound: a Randomized Clinical Trial.
    Date August 2001
    Journal Diabetes Care
    Excerpt

    OBJECTIVE--To compare the effectiveness of total-contact casts (TCCs), removable cast walkers (RCWs), and half-shoes to heal neuropathic foot ulcerations in individuals with diabetes. RESEARCH DESIGN AND METHODS--In this prospective clinical trial, 63 patients with superficial noninfected, nonischemic diabetic plantar foot ulcers were randomized to one of three off-loading modalities: TCC, half-shoe, or RCW. Outcomes were assessed at wound healing or at 12 weeks, whichever came first. Primary outcome measures included proportion of complete wound healing at 12 weeks and activity (defined as steps per day). RESULTS--The proportions of healing for patients treated with TCC, RCW, and half-shoe were 89.5, 65.0, and 58.3%, respectively. A significantly higher proportion of patients were healed by 12 weeks in the TCC group when compared with the two other modalities (89.5 vs. 61.4%, P = 0.026, odds ratio 5.4, 95% CI 1.1-26.1). There was also a significant difference in survival distribution (time to healing) between patients treated with a TCC and both an RCW (P = 0.033) and half-shoe (P = 0.012). Patients were significantly less active in the TCC (600.1 +/- 320.0 daily steps) compared with the half-shoe (1,461.8 +/- 1,452.3 daily steps, P = 0.04). There was no significant difference in the average number of steps between the TCC and the RCW (767.6 +/- 563.3 daily steps, P = 0.67) or the RCW and the half-shoe (P = 0.15). CONCLUSIONS--The TCC seems to heal a higher proportion of wounds in a shorter amount of time than two other widely used off-loading modalities, the RCW and the half-shoe.

    Title A Comparison of Two Diabetic Foot Ulcer Classification Systems: the Wagner and the University of Texas Wound Classification Systems.
    Date May 2001
    Journal Diabetes Care
    Excerpt

    OBJECTIVE: In this study the following two ulcer classification systems were applied to new foot ulcers to compare them as predictors of outcome: the Wagner (grade) and the University of Texas (LT) (grade and stage) wound classification systems. RESEARCH DESIGN AND METHODS: Ulcer size, appearance, clinical evidence of infection, ischemia, and neuropathy at presentation were recorded, and patients were followed up until healing or for 6 months. RESULTS: Of 194 patients with new foot ulcers, 67.0% were neuropathic, 26.3% were neuroischemic, 1.0% were ischemic, and 5.7% had no identified underlying factors. Median (interquartile range [IQR]) ulcer size at presentation was 1.5 cm2 (0.6-4.0). Lower-limb amputations were performed for 15% of ulcers, whereas 65% healed [median (IQR) healing time 5 (3-10) weeks] and 16% were not healed at study termination; 4% of patients died. Wagner grade (P < 0.0001), and UT grade (P < 0.0001) and stage (P < 0.001) showed positive trends with increased number of amputations. For UT stage, the risk of amputation increased with infection both alone (odds ratio [OR] = 11.1, P < 0.0001) and in combination with ischemia (OR = 14.7, P < 0.0001), but not significantly with ischemia alone (OR = 4.6, P = 0.09). Healing times were not significantly different for each grade of the Wagner (P = 0.1) or the UT system (P = 0.07), but there was a significant stepwise increase in healing time with each stage of the UT system (P < 0.05), and stage predicted healing (P < 0.05). CONCLUSIONS: Increasing stage, regardless of grade, is associated with increased risk of amputation and prolonged ulcer healing time. The UT system's inclusion of stage makes it a better predictor of outcome.

    Title The Effects of Ulcer Size and Site, Patient's Age, Sex and Type and Duration of Diabetes on the Outcome of Diabetic Foot Ulcers.
    Date May 2001
    Journal Diabetic Medicine : a Journal of the British Diabetic Association
    Excerpt

    AIMS: The outcome of foot ulcers is affected by wound depth, infection, ischaemia and glycaemic control. The aim of this study was to determine the effects of ulcer size, site, patient's age, sex and type and duration of diabetes on the outcome of diabetic foot ulcers. METHODS: Diabetic patients with new foot ulcers presenting during a 12-month period had demographics and ulcer characteristics recorded at presentation. Ulcers were followed-up until an outcome was noted. RESULTS: One hundred and ninety-four patients (77% males) with a mean (+/- SD) age and duration of diabetes of 56.6 +/- 12.6 and 15.4 +/- 9.9 years, respectively, were included in the study. The majority of ulcers were neuropathic (67.0%) and present on the forefoot (77.8%) with a median (interquartile range) area of 1.5 (0.6-4.0) cm2. Amputations were performed for 15% of ulcers; 65% healed; 16% remained unhealed and 4% of patients died. The median (95% confidence interval) time to healing was 10 (8.8-11.6) weeks. Ulcer area at presentation was greater in the amputation group compared to healed ulcers (3.9 vs. 1.2 cm2, P < 0.0001). Ulcer area correlated with healing time (rs = 0.27, P < 0.0001) and predicted healing (P = 0.04). Patient's age, sex, duration/type of diabetes, and ulcer site had no effect on outcome. CONCLUSIONS: Ulcer area, a measure of ulcer size, predicts the outcome of foot ulcers. Its inclusion into a diabetic wound classification system will make that system a better predictor of outcome.

    Title Improvement in Healing with Aggressive Edema Reduction After Debridement of Foot Infection in Persons with Diabetes.
    Date February 2001
    Journal Archives of Surgery (chicago, Ill. : 1960)
    Excerpt

    BACKGROUND: Infected foot wounds in patients with diabetes are the most common reason for diabetes-related hospital admission in the United States. Nonhealing foot wounds are the major precipitant of lower-extremity amputation in the diabetic population. HYPOTHESIS: The null hypothesis was that there would be no difference in proportion of healing with or without use of a foot-level mechanical compression device. DESIGN: Twelve-week, double-blind, randomized, controlled trial. SETTING: A university teaching hospital and related clinics. PATIENTS: One hundred fifteen patients with diabetes, 74% male, with foot infections requiring incision and debridement. INTERVENTION: All patients received either a functioning or placebo (nonfunctioning) foot compression device (Kinetic Concepts Inc, San Antonio, Tex). Patients and investigators were blinded to the functionality of the device. PRIMARY OUTCOME MEASURE: Proportion of wound healing in each group. RESULTS: There was a significantly higher proportion of healing in the active group than in the placebo group (39 [75%] of 52 patients vs 23 [51%] of 45; chi(2) = 6.0; P<.02; odds ratio, 2.9; 95% confidence interval, 1. 2-6.8). In the placebo group, there was no difference in proportion of healing between those identified as compliant (>/=50 hours of use per week) vs noncompliant (P =.10). In patients receiving active units, more patients in the compliant subgroup experienced wound healing (P<.03). When compared as a whole, there was a significant trend toward an increasing proportion of healing from the placebo-noncompliant to the placebo-compliant to the active-noncompliant to the active-compliant groups (chi(2)(trend) = 8.3; P<.005). CONCLUSIONS: Edema reduction achieved in this study by way of a pump and wrap system may increase the proportion of wound healing in patients after debridement of foot infections in patients with diabetes. Furthermore, the data suggest a potential association between increased compliance with use of the device and an increased trend toward wound healing. Arch Surg. 2000;135:1405-1409

    Title Incidence of Childhood Cancer in Ho Chi Minh City, Vietnam, 1995-97.
    Date December 2000
    Journal Paediatric and Perinatal Epidemiology
    Excerpt

    Incidence rates of childhood cancer for the city of Ho Chi Minh are presented for the first time. For the 3-year period 1995-97, a total of 302 cancer cases were registered in children under 15 years of age, with a male to female ratio of 1.1. The overall crude rate was 78.8 and the age-standardised incidence rate was 88.4 per million person-years, which was low in comparison with other countries in eastern Asia and with the predominantly white population of Australia. Leukaemia (principally acute lymphocytic), brain tumours and lymphomas were the most common childhood neoplasms, which is consistent with the pattern observed in other registries of the region. The rate of retinoblastoma was higher than in the other regional registries. On the other hand, no cases of hepatocellular carcinoma were registered.

    Title Technique for Preventing Air Embolism During Cardiac Surgery.
    Date December 1999
    Journal The Journal of Cardiovascular Surgery
    Title Role of Photoperiod and the Pineal Gland in T Cell-dependent Humoral Immune Reactivity in the Siberian Hamster.
    Date December 1999
    Journal Journal of Pineal Research
    Excerpt

    The present study tested the hypothesis that antibody production in response to xenoantigen is modulated by daylength and dependent upon the pineal gland. Alter injection of sheep erythrocytes (SRBC), serum immunoglobulin (Ig) concentrations were 5-fold lower in hamsters in short versus long days. Pinealectomy (Pinx) abolished the nocturnal melatonin rhythm, blocked short-day-mediated testis regression, and eliminated the short-day reduction in Ig production after SRBC treatment. Antibody titers in response to SRBC were equivalently augmented in short-day Pinx and long-day sham hamsters. The results indicate that photoperiodic effects on T cell-dependent humoral immunity are dependent upon the pineal gland. These findings raise the possibility that day length-associated changes in some immune system functions are mediated by the pineal melatonin rhythm.

    Title Factors Associated with Bone Regrowth Following Diabetes-related Partial Amputation of the Foot.
    Date November 1999
    Journal The Journal of Bone and Joint Surgery. American Volume
    Excerpt

    BACKGROUND: The formation of hypertrophic bone after partial resection of metatarsal bone has the potential to cause abnormal foci of high pressure in people who have diabetes mellitus; this may increase the risk of reulceration and reamputation. However, we are not aware of previous studies evaluating the risk factors for this entity. METHODS: The records of ninety-two adults (mean age, 54+/-10.1 years; range, thirty to seventy-four years) with diabetes who had had an isolated partial amputation of a ray were abstracted. Repeat radiographs were made for all of these subjects at a mean of 22+/-6.1 months (range, thirteen to thirty-five months) after the initial procedure. The formation of hypertrophic bone was defined as more than three millimeters of regrowth. RESULTS: A total of forty-one (45 percent) of the subjects had formation of hypertrophic bone at the time of radiographic analysis after isolated partial amputation of a ray. On multivariate analysis, the factors that were significantly associated with this regrowth of bone were male gender (88 percent [thirty-six] of the forty-one patients who had bone regrowth were male compared with 51 percent [twenty-six] of the fifty-one patients who did not have bone regrowth; p<0.01, odds ratio = 5.7, 95 percent confidence interval = 1.8 to 18.9), the use of manual bone-cutting instruments (used in 56 percent [twenty-three] of the forty-one patients who had bone regrowth compared with 16 percent [eight] of the fifty-one who did not; p<0.01, odds ratio = 4.7, 95 percent confidence interval = 1.6 to 13.8), and a resection made distal to the surgical neck of the metatarsal (used in 34 percent [fourteen] of the forty-one patients who had bone regrowth compared with 12 percent [six] of the fifty-one who did not; p<0.03, odds ratio = 4.5, 95 percent confidence interval = 1.2 to 16.9). The patients who had regrowth of bone were approximately eight times more likely to have reulceration at the site of the amputation than were those who did not have regrowth (24 percent [ten] of the patients with regrowth had reulceration compared with 4 percent [two] of the patients without regrowth; p<0.01, chi square = 8.4, odds ratio = 7.9, 95 percent confidence interval = 1.6 to 38.5). CONCLUSIONS: Overgrowth of the bone of a transected metatarsal predisposes patients to ulceration. Male gender, the use of manual bone-cutting instruments, and metaphyseal amputation may be associated with long-term regrowth of bone following isolated partial amputation of a ray. The use of power instruments during these procedures may lead to a lower prevalence of this reaction, thereby potentially reducing the risk of ulceration, infection, and reamputation.

    Title Further Characterization of Hiv-1 Isolates from Ho Chi Minh City, Vietnam.
    Date February 1999
    Journal Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology : Official Publication of the International Retrovirology Association
    Title Cancer Incidence in Ho Chi Minh City, Viet Nam, 1995-1996.
    Date June 1998
    Journal International Journal of Cancer. Journal International Du Cancer
    Excerpt

    The results from the population-based cancer registry for the city of Ho Chi Minh in 1995-1996 represent the first information on the incidence of cancer in southern Viet Nam. A total of 4,080 cancer cases in males and 4,338 in females were registered, corresponding to age-standardized incidence rates (ASRs) of 130.9 per 100,000 in men and 100.7 per 100,000 in women. As elsewhere in South East Asia, the principal cancer of men was liver cancer (ASR 25.3), with moderately high rates of lung cancer (ASR 24.6) and stomach cancer (ASR 16.5); cancer of the penis, reportedly very common in early case series from Viet Nam, is now rarely seen. In women, cervical cancer was the dominant malignancy (ASR 26.0) followed by breast cancer (ASR 12.2) and stomach cancer (ASR 7.5). Although there may be some under-registration in these early years of operation, the recorded rates of cervical cancer and liver cancer are already high and suggest that southern Viet Nam would benefit from an effective cervical cancer screening programme, as well as efforts to interrupt the transmission of hepatitis B virus to reduce liver cancer incidence and effective anti-smoking programs.

    Title Zenker's Diverticulum.
    Date December 1997
    Journal The Laryngoscope
    Excerpt

    Symptomatic Zenker's diverticula are usually treated with diverticulectomy and myotomy. Other, more conservative open procedures consist of diverticulopexy, imbrication, and myotomy alone. These more conservative procedures do not result in a breach of esophageal mucosa and should have more rapid postoperative recovery. We performed a retrospective chart review of all open surgical procedures performed at the Marshfield Clinic and St. Joseph's Hospital between 1975 and 1996. Using Wilcoxon's rank sum test, the conservative procedures were compared with the standard diverticulectomy for duration of hospitalization and length of time to resumption of oral intake. Fifty-nine patients are reported. Statistically significant differences between the surgery groups were found for hospitalization (P < 0.001) and days to resumption of oral intake (P < 0.001). Conservative open surgical procedures for repair of Zenker's diverticula result in decreased hospitalization and earlier resumption of oral diet compared with diverticulectomy.

    Title [clinical and Epidemiologic Aspects of Hiv Infection Among Drug Addicts in Ho Chi Minh City]
    Date September 1996
    Journal Santé (montrouge, France)
    Title Mammary Artery Versus Saphenous Vein Grafts: Assessment of Basic Fibroblast Growth Factor Receptors.
    Date September 1994
    Journal The Annals of Thoracic Surgery
    Excerpt

    Neointimal hyperplasia limits the long-term patency of saphenous vein grafts (SVGs), but is notably absent from most internal mammary artery (IMA) grafts. Basic fibroblast growth factor (bFGF) is a local endothelial and vascular smooth muscle mitogen known to be involved in the pathogenesis of neointimal hyperplasia. This study used an animal model to compare the number of available high-affinity (HAR) and low-affinity (LAR) bFGF receptors in SVGs and IMA grafts and to determine whether distention injury causes an increase in receptor availability. The IMA and SVG specimens were harvested from 12 dogs and distended at 25 or 200 mm Hg for 15 minutes, and then the bFGF receptor uptake was measured in them using iodine 125-labeled bFGF. In the IMA conduits distended at low pressure, there were 2.54 +/- 0.10 (mean +/- standard error of the mean) HARs per mm2 of intimal surface area available and 5.19 +/- 0.40 LARs per mm2. High-pressure distention significantly (p < 0.001) increased the number of available HARs to 5.06 +/- 0.27 per mm2 and of LARs to 7.27 +/- 0.042 per mm2. At low pressure, the SVGs had significantly (p < 0.001) more HARs (9.14 +/- 0.84 per mm2) and LARs (18.2 +/- 0.57 per mm2) available than did the IMA conduits, and high pressure significantly (p < 0.001) increased the number of HARs available in SVGs to 24.1 +/- 2.43 per mm2 and the number of LARs to 44.7 +/- 2.34 per mm2.(ABSTRACT TRUNCATED AT 250 WORDS)

    Title Suppression of Neointimal Lesions After Vascular Injury: a Role for Polyclonal Anti-basic Fibroblast Growth Factor Antibody.
    Date August 1994
    Journal Surgery
    Excerpt

    BACKGROUND. Basic fibroblast growth factor (bFGF) is a potent local promoter of vascular smooth muscle cell migration and proliferation and may play a major role in the pathogenesis of intimal fibromuscular lesions. Preliminary studies have shown that exogenous bFGF localizes to injured rabbit aorta and suggest that this interaction might be inhibited by anti-bFGF immunoglobulin (Ig) G. This study was designed to evaluate the possible role of polyclonal anti-bFGF IgG in reducing intimal fibromuscular lesion formation in the injured rabbit aorta. METHODS. The abdominal aortic endothelium was subjected to balloon injury in 13 rabbits. Six rabbits received intravenous rabbit anti-bFGF IgG, and seven received irrelevant rabbit IgG (16 micrograms/kg) 30 minutes before injury and daily for 5 days after injury. At 14 days after injury the aorta was fixed and sectioned, and the intimal and medial areas were measured by computerized digital morphometry with the intimal/medial ratio as an index of neointimal lesion formation. RESULTS. In the control group the intimal/medial ratio was 0.538 +/- 0.046 (mean +/- SEM), which was significantly greater than the anti-bFGF-treated group value of 0.148 +/- 0.021 (p < 0.001). CONCLUSIONS. These results show that daily doses of intravenous polyclonal anti-bFGF IgG for 5 days after balloon aortic injury significantly inhibit intimal fibromuscular lesion formation at 14 days. The results suggest that the process of intimal fibromuscular lesion formation may be susceptible to modification by antagonists to bFGF.

    Title [epidemic Due to Echo Virus 30. I. Clinical and Biological Study]
    Date April 1971
    Journal Annales De Pédiatrie
    Title Magnetic Studies of Some Orthovanadates.
    Date
    Journal Physical Review. B, Condensed Matter
    Title Localized-itinerant Electronic Transition in the Perovskite System La1-xcaxvo3.
    Date
    Journal Physical Review. B, Condensed Matter
    Title Ultrafast All-optical Chalcogenide Glass Photonic Circuits.
    Date
    Journal Optics Express
    Excerpt

    <p> <a href="http://oe.osa.org/virtual_issue.cfm?vid=36">Focus Serial: Frontiers of Nonlinear Optics</a> </p>Chalcogenide glasses offer large ultrafast third-order nonlinearities, low two-photon absorption and the absence of free carrier absorption in a photosensitive medium. This unique combination of properties is nearly ideal for all-optical signal processing devices. In this paper we review the key properties of these materials, outline progress in the field and focus on several recent highlights: high quality gratings, signal regeneration, pulse compression and wavelength conversion.

    Title Enhanced Kerr Nonlinearity in Sub-wavelength Diameter As(2)se(3) Chalcogenide Fiber Tapers.
    Date
    Journal Optics Express
    Excerpt

    We experimentally demonstrate enhanced Kerr nonlinear effects in highly nonlinear As(2)Se(3) chalcogenide fiber tapered down to sub-wavelength waist diameter of 1.2 mum. Based on self phase modulation measurements, we infer an enhanced nonlinearity of 68 W(-1)m(-1). This is 62,000 times larger than in standard silica singlemode fiber, owing to the 500 times larger n(2) and almost 125 times smaller effective mode area. We also consider the potential to exploit the modified dispersion in these tapers for ultra-low threshold supercontinuum generation.


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