Pediatric Specialists
22 years of experience
Video profile
Accepting new patients
Willow Grove
Urology for Children
2701 Blair Mill Rd
Ste 6
Willow Grove, PA 19090
203-648-4990
Locations and availability (10)

Education ?

Medical School Score Rankings
Columbia University (1988)
  • Currently 4 of 4 apples
Top 25%

Awards & Distinctions ?

Awards  
Patients' Choice Award (2008 - 2009, 2013)
Compassionate Doctor Recognition (2013)
Associations
American Board of Urology
American Urological Association

Affiliations ?

Dr. Dean is affiliated with 22 hospitals.

Hospital Affilations

Score

Rankings

  • Lehigh Valley Hospital
    Urology
    1200 S Cedar Crest Blvd, Allentown, PA 18103
    • Currently 3 of 4 crosses
    Top 50%
  • Our Lady Of Lourdes Medical Center
    Urology
    1600 Haddon Ave, Camden, NJ 08103
    • Currently 3 of 4 crosses
    Top 50%
  • Virtua West Jersey Hospital - Berlin
    Urology
    94 Brick Rd, Marlton, NJ 08053
    • Currently 3 of 4 crosses
    Top 50%
  • Temple University Hospital
    3401 N Broad St, Philadelphia, PA 19140
    • Currently 2 of 4 crosses
  • Virtua West Jersey Hospital - Voorhees
    94 Brick Rd, Marlton, NJ 08053
    • Currently 2 of 4 crosses
  • Abington Memorial Hospital
    1200 Old York Rd, Abington, PA 19001
    • Currently 2 of 4 crosses
  • Saint Christopher's Hospital for Children
    3601 A St, Philadelphia, PA 19134
    • Currently 2 of 4 crosses
  • Warminster Hospital
    225 Newtown Rd, Warminster, PA 18974
    • Currently 2 of 4 crosses
  • Cooper University Hospital
    Urology
    1 Cooper Plz, Camden, NJ 08103
    • Currently 1 of 4 crosses
  • Lourdes Medical Center of Burlington County
    218A Sunset Rd, Willingboro, NJ 08046
    • Currently 1 of 4 crosses
  • Virtua West Jersey Hospital - Marlton
    Urology
    94 Brick Rd, Marlton, NJ 08053
    • Currently 1 of 4 crosses
  • Lehigh Valley Hospital - Muhlenberg
    Urology
    2545 Schoenersville Rd, Bethlehem, PA 18017
    • Currently 1 of 4 crosses
  • Summit Surgical Center
  • Summit County Hospital
    19 Prospect St, Summit, NJ 07901
  • Virtua-West Jersey Health System
  • Temple University Hospital - Episcopal Campus
    100 E Lehigh Ave, Philadelphia, PA 19125
  • Warminster Hospital
  • Temple University Childrens Medical Center
  • Virtua WJ Hospital Voorhees
  • Cooper HospitalU M C
  • Virtua Memorial Hospital
  • Temple Univ Child`s Med Ctr
  • Publications & Research

    Dr. Dean has contributed to 68 publications.
    Title Feasibility of a Femoral Nerve Motor Branch for Transfer to the Pudendal Nerve for Restoring Continence: a Cadaveric Study.
    Date December 2011
    Journal Journal of Neurosurgery. Spine
    Excerpt

    Nerve transfers are an effective means of restoring control to paralyzed somatic muscle groups and, recently, even denervated detrusor muscle. The authors performed a cadaveric pilot project to examine the feasibility of restoring control to the urethral and anal sphincters using a femoral motor nerve branch to reinnervate the pudendal nerve through a perineal approach.

    Title Outpatient Perineal Sling in Adolescent Boys with Neurogenic Incontinence.
    Date October 2009
    Journal The Journal of Urology
    Excerpt

    Management for urinary incontinence in boys with sphincteric incompetence secondary to a neurogenic etiology is a challenge. Minimally invasive approaches have inconsistent efficacy and may require multiple treatments. Open bladder neck reconstruction requires inpatient hospitalizations and can be associated with a high complication rate. To overcome some of these shortcomings we placed a polypropylene male perineal sling in male adolescents with neurogenic sphincteric incontinence. We retrospectively reviewed the outcome in our initial 6 patients.

    Title Editorial Comment.
    Date October 2009
    Journal The Journal of Urology
    Title Development and Evaluation of a Genetics Literacy Assessment Instrument for Undergraduates.
    Date March 2008
    Journal Genetics
    Excerpt

    There is continued emphasis on increasing and improving genetics education for grades K-12, for medical professionals, and for the general public. Another critical audience is undergraduate students in introductory biology and genetics courses. To improve the learning of genetics, there is a need to first assess students' understanding of genetics concepts and their level of genetics literacy (i.e., genetics knowledge as it relates to, and affects, their lives). We have developed and evaluated a new instrument to assess the genetics literacy of undergraduate students taking introductory biology or genetics courses. The Genetics Literacy Assessment Instrument is a 31-item multiple-choice test that addresses 17 concepts identified as central to genetics literacy. The items were selected and modified on the basis of reviews by 25 genetics professionals and educators. The instrument underwent additional analysis in student focus groups and pilot testing. It has been evaluated using approximately 400 students in eight introductory nonmajor biology and genetics courses. The content validity, discriminant validity, internal reliability, and stability of the instrument have been considered. This project directly enhances genetics education research by providing a valid and reliable instrument for assessing the genetics literacy of undergraduate students.

    Title The Relationship Between Nurse Work Schedules, Sleep Duration, and Drowsy Driving.
    Date March 2008
    Journal Sleep
    Excerpt

    STUDY OBJECTIVES: Recent studies have shown that extended shifts worked by hospital staff nurses are associated with significantly higher risk of errors, yet little information is available about the ability to remain alert during the nurses' commutes following the completion of an extended work shift. The purpose of this study is to describe the prevalence of drowsy driving episodes and the relationship between drowsy driving and nurse work hours, alertness on duty, working at night, and sleep duration. PARTICIPANTS: Data were collected from 2 national random samples of registered nurses (n=895). MEASUREMENTS AND RESULTS: Full-time hospital staff nurses (n=895) completed logbooks on a daily basis for 4 weeks providing information concerning work hours, sleep duration, drowsy and sleep episodes at work, and drowsy driving occurrences. Almost 600 of the nurses (596/895) reported at least 1 episode of drowsy driving, and 30 nurses reported experiencing drowsy driving following every shift worked. Shorter sleep durations, working at night, and difficulties remaining awake at work significantly increased the likelihood of drowsy driving episodes. CONCLUSIONS: Given the large numbers of nurses who reported struggling to stay awake when driving home from work and the frequency with which nurses reported drowsy driving, greater attention should be paid to increasing nurse awareness of the risks and to implementing strategies to prevent drowsy driving episodes to ensure public safety. Without mitigation, fatigued nurses will continue to put the public and themselves at risk.

    Title Sleep and Quality of Life in Long-term Lung Cancer Survivors.
    Date February 2008
    Journal Lung Cancer (amsterdam, Netherlands)
    Excerpt

    BACKGROUND: Sleep problems are common in lung cancer survivors, yet little is known about the prevalence, determinants, and effects on quality of life (QoL) of these sleep problems in long-term lung cancer survivors. METHODS: A case-control study design comparing 76 elderly lung cancer survivors (LCS, >5 years post diagnosis with mean survival time of 8 years+/-2.1 years) and 78 elderly non-cancer controls (NCC). Measurements included a standardized questionnaire for sleep (Pittsburgh Sleep Quality Index-PSQI), and analogue scales for dyspnea, pain, and other comorbid symptoms, as well as demographic factors and cancer history. RESULTS: Overall, 56.6% of LCS had poor sleep (PSQI global score >5) as compared to only 29.5% of NCC (p<0.001), and 49.2% of LCS who did not have sleep difficulties prior to their lung cancer diagnosis ultimately developed them. There was also evidence of significant impairments in sleep efficiency in LCS (78.3%) relative to NCC (89.6%, p<0.001), predominantly due to increased nocturnal awakenings. A single-item analogue scale for sleep quality was not as effective in identifying sleep problems as more specific questions about sleep duration and sleep efficiency. Poor sleep quality was significantly correlated with impairments in quality of life, even when controlling for other factors, such as dyspnea. CONCLUSIONS: Even 8 years after diagnosis, LCS continue to have significant sleep difficulties. By asking specific questions about sleep medication use, nocturnal awakenings and sleep efficiency, health care providers can identify sleep problems that could be treated and potentially improve the quality of life of their patients.

    Title Antegrade and Retrograde Endoscopic Dextranomer/hyaluronic Acid Bladder Neck Bulking for Pediatric Incontinence.
    Date August 2007
    Journal The Journal of Urology
    Excerpt

    PURPOSE: Endoscopic bladder neck bulking techniques offer the potential for a relatively noninvasive cure for a difficult clinical problem. We review our experience using antegrade and retrograde approaches. MATERIALS AND METHODS: A total of 34 children (18 boys and 16 girls, mean age 11.7 years) have been treated since March 2003. Of the patients 28 (82%) had neurogenic bladder and 6 had nonneurogenic sphincteric incontinence. Urodynamics confirmed low detrusor leak point pressures and adequate bladder capacity. Patients were treated with either a retrograde or an antegrade approach. In 82% of patients an antegrade approach was used and a posttreatment suprapubic tube was placed. RESULTS: Mean followup was 11.7 months (range 3 to 31). Patients averaged 1.47 injections (range 1 to 5). Detailed followup of 19 patients revealed significant improvement in continence in 78% (mean 1.6 injections), with an average followup of approximately 1 year. CONCLUSIONS: Our 31 months of experience with antegrade/retrograde bladder neck bulking demonstrates that it is a viable therapy for this group of children. While some patients have experienced prolonged success, re-treatment can be beneficial. The antegrade approach offers several advantages, including intraoperative leak point pressures, improved visualization and placement of a suprapubic tube to limit post-procedural remodeling.

    Title Infants at Risk: when Nurse Fatigue Jeopardizes Quality Care.
    Date November 2006
    Journal Advances in Neonatal Care : Official Journal of the National Association of Neonatal Nurses
    Excerpt

    Although most research on medical error has been conducted on adult inpatient units, the few studies conducted in pediatric settings suggest that errors occur more frequently in neonatal intensive care units (NICUs) than in other inpatient units. The effects of fatigue, due to long work hours, working at night, and insufficient sleep, are often underestimated. This article reviews basic information about fatigue and sleep and includes examples drawn from data provided by 6 NICU nurses who participated in a recent study to highlight the relationship between fatigue and error. These case studies reinforce the concept that NICU nurses need to be alert enough to provide safe care for their patients, as well as alert enough to detect and correct the errors made by others. Employing good sleep habits, minimizing shift rotations and excessive work hours, and using strategic naps can reduce the adverse effects of fatigue that could potentially put patients, especially the most vulnerable ones, at risk.

    Title The Extended Use of Deflux (dextranomer/hyaluronic Acid) in Pediatric Urology.
    Date July 2006
    Journal Current Urology Reports
    Excerpt

    The use of injectable bulking agents into the submucosal layer of the pediatric urinary tract continues to grow. Treatment strategies for vesicoureteral reflux and urinary incontinence have changed with the introduction of dextranomer/hyaluronic acid as a minimally invasive option. Socially and medically debilitating conditions requiring major surgical reconstruction and hospitalization in the past have now been replaced by outpatient endoscopic procedures. As experience has been gained, broader uses of this agent have been applied to more complex etiologies of reflux and incontinence.

    Title A New Method to Remove Hybridization Bias for Interspecies Comparison of Global Gene Expression Profiles Uncovers an Association Between Mrna Sequence Divergence and Differential Gene Expression in Xenopus.
    Date January 2006
    Journal Nucleic Acids Research
    Excerpt

    The recent sequencing of a large number of Xenopus tropicalis expressed sequences has allowed development of a high-throughput approach to study Xenopus global RNA gene expression. We examined the global gene expression similarities and differences between the historically significant Xenopus laevis model system and the increasingly used X.tropicalis model system and assessed whether an X.tropicalis microarray platform can be used for X.laevis. These closely related species were also used to investigate a more general question: is there an association between mRNA sequence divergence and differences in gene expression levels? We carried out a comprehensive comparison of global gene expression profiles using microarrays of different tissues and developmental stages of X.laevis and X.tropicalis. We (i) show that the X.tropicalis probes provide an efficacious microarray platform for X.laevis, (ii) describe methods to compare interspecies mRNA profiles that correct differences in hybridization efficiency and (iii) show independently of hybridization bias that as mRNA sequence divergence increases between X.laevis and X.tropicalis differences in mRNA expression levels also increase.

    Title Glandular Hypospadias Repair.
    Date December 2002
    Journal The Urologic Clinics of North America
    Excerpt

    Glandular hypospadias represents approximately 15% of the hypospadias variants seen. This article will examine common surgical approaches applicable to the child with glandular hypospadias. Hypospadias repairs discussed in this article will include urethromeatoplasty, MAGPI, the GAP procedure, MIV glans plasty, urethral advancement procedure, and parameatal based flap variants, including the Mathieu and Barcat procedures. Because these anomalies are cosmetically less aberrant than more proximal variants, only those surgical techniques which assure a normal-appearing penis should be undertaken.

    Title Increasing the Visibility of Patient Fatigue.
    Date August 2002
    Journal Seminars in Oncology Nursing
    Excerpt

    OBJECTIVES: To describe the process used by our cancer center to assess staff knowledge and attitudes about cancer-related fatigue, and to change clinical practice of fatigue assessment and management. DATA SOURCES: Review articles, research studies, guidelines, and questionnaires. CONCLUSIONS: Change in clinical practice occurs slowly. One major change that occurred was the inclusion of a fatigue question in the Daily Patient Care Record. This inclusion signified a commitment by the institution to address this under-reported and under-treated symptom. IMPLICATIONS FOR NURSING PRACTICE: Professionals challenged to pursue practice change must be passionate, persistent, and patient. A multidisciplinary effort is needed to support change.

    Title Synaptotagmin I-deltac2b. A Novel Synaptotagmin Isoform with a Single C2 Domain in the Bovine Adrenal Medulla.
    Date June 2002
    Journal Biochimica Et Biophysica Acta
    Excerpt

    Synaptotagmin I is a 65 kDa type 1 membrane glycoprotein found in secretory organelles that plays a key role in regulated exocytosis. We have characterised two forms (long and short) of synaptotagmin I that are present in the bovine adrenal medulla. The long form is a type I integral membrane protein which has two cytoplasmic C2 domains and corresponds to the previously characterised full-length synaptotagmin I isoform. The short-form synaptotagmin I-DeltaC2B has the same structure in the lumenal and transmembrane sequences, but synaptotagmin I-DeltaC2B is truncated such that it only has a single cytoplasmic C2 domain. Analysis of synaptotagmin I-DeltaC2B expression indicates that synaptotagmin I-DeltaC2B is preferentially expressed in the bovine adrenal medulla. However, it is absent from the dense core chromaffin granules. Furthermore, when expressed in the rat pheochromocytoma cell line PC12 bovine synaptotagmin I-DeltaC2B is largely absent from dense core granules and synaptic-like microvesicles. Instead, indirect immunofluorescence microscopy reveals the intracellular location of synaptotagmin I-DeltaC2B to be the plasma membrane.

    Title Laparoscopically Assisted Correction of Transverse Testicular Ectopia.
    Date May 2002
    Journal The Journal of Urology
    Title Meconium Pearls in the Scrotum.
    Date October 2000
    Journal The Journal of Urology
    Title Ankb, a Periplasmic Ankyrin-like Protein in Pseudomonas Aeruginosa, is Required for Optimal Catalase B (katb) Activity and Resistance to Hydrogen Peroxide.
    Date August 2000
    Journal Journal of Bacteriology
    Excerpt

    In this study, we have cloned the ankB gene, encoding an ankyrin-like protein in Pseudomonas aeruginosa. The ankB gene is composed of 549 bp encoding a protein of 183 amino acids that possesses four 33-amino-acid ankyrin repeats that are a hallmark of erythrocyte and brain ankyrins. The location of ankB is 57 bp downstream of katB, encoding a hydrogen peroxide-inducible catalase, KatB. Monomeric AnkB is a 19.4-kDa protein with a pI of 5.5 that possesses 22 primarily hydrophobic amino acids at residues 3 to 25, predicting an inner-membrane-spanning motif with the N terminus in the cytoplasm and the C terminus in the periplasm. Such an orientation in the cytoplasmic membrane and, ultimately, periplasmic space was confirmed using AnkB-BlaM and AnkB-PhoA protein fusions. Circular dichroism analysis of recombinant AnkB minus its signal peptide revealed a secondary structure that is approximately 65% alpha-helical. RNase protection and KatB- and AnkB-LacZ translational fusion analyses indicated that katB and ankB are part of a small operon whose transcription is induced dramatically by H(2)O(2), and controlled by the global transactivator OxyR. Interestingly, unlike the spherical nature of ankyrin-deficient erythrocytes, the cellular morphology of an ankB mutant was identical to that of wild-type bacteria, yet the mutant produced more membrane vesicles. The mutant also exhibited a fourfold reduction in KatB activity and increased sensitivity to H(2)O(2), phenotypes that could be complemented in trans by a plasmid constitutively expressing ankB. Our results suggest that AnkB may form an antioxidant scaffolding with KatB in the periplasm at the cytoplasmic membrane, thus providing a protective lattice work for optimal H(2)O(2) detoxification.

    Title La Vega Slit Procedure for the Treatment of Phimosis.
    Date March 2000
    Journal Urology
    Excerpt

    OBJECTIVES: The surgical treatment of phimosis is usually circumcision. In countries in which circumcision is not widely practiced, this approach results in a phallus that is cosmetically unacceptable. We applied a ventral slit procedure to boys with severe phimosis and achieved outstanding results. METHODS: All patients were selected during a 1-week medical mission to La Vega in the Dominican Republic during April 1997. Eight patients presented with severe phimosis. The patient age ranged from 3 to 7 years (mean 4.4). All patients were cleared by the team pediatrician before undergoing the procedure. RESULTS: Eight patients underwent the procedure without complications. The operative time was less than 10 minutes in all instances. All had excellent postoperative cosmesis, were able to retract their foreskins, and voided without difficulty. A follow-up mission to La Vega in March 1998 yielded no complications involving this group of patients. CONCLUSIONS: Unlike circumcision and the dorsal slit procedure, this approach yields a phallus that on initial appearance is indistinguishable from an uncircumcised phallus. The procedure is easily performed and should be considered in the treatment of phimosis whenever foreskin preservation is desired.

    Title Chordee Repair Utilizing a Novel Technique Ensuring Neurovascular Bundle Preservation.
    Date March 2000
    Journal Techniques in Urology
    Excerpt

    Penile chordee, with and without hypospadias, is amenable to surgical correction. The Nesbit technique of dorsal plication of the ventral tunica albuginea is effective in correcting most cases of corporal disproportion. A hazard with this approach is the potential inclusion of the dorsal neurovascular bundle, with resultant erectile and sensory dysfunction. We developed a simple technique using the Freer elevator to isolate the neurovascular bundle prior to plication. This ensures that no injury occurs to the neurovascular bundle during plication. Since 1994, 37 boys with chordee have been repaired using this approach. Their ages at the time of operation ranged from 5 months to 28 years (mean 9 months). Following standard degloving of the penis, an incision through Buck's fascia is made lateral and parallel to the neurovascular bundle at the maximum level of the chordee. A similar incision is carried out on the contralateral side. A 4-mm-wide Freer elevator is positioned under Buck's fascia while hugging the tunica albuginea. The Freer elevator slides across the midline to the contralateral side, separating Buck's fascia and underlying layers from the tunica albuginea. Following isolation of the bundle, each corporal body is plicated by creating a longitudinal incision through the tunica albuginea, which then is closed transversely with a 5-0 polydioxanone suture. Buck's fascia subsequently is closed with an absorbable suture following confirmation of chordee correction. No complications have been encountered during a mean follow-up of 21 months (range 5-51 months). No patients have required reoperation for persistent chordee. We developed a technique that elevates the neurovascular bundle prior to plication, thereby ensuring no injury to this structure. We have successfully used this modified Nesbit technique since 1994 and have had no complications. Utilization of the Freer elevator adds an estimated 5 minutes to chordee correction compared to a standard plication lateral to the neurovascular bundles. Although long-term follow-up needs to be performed to confirm any erectile or sensory advantage, this approach should be considered whenever plication is to be performed.

    Title Medical Management of Phimosis in Children: Our Experience with Topical Steroids.
    Date September 1999
    Journal The Journal of Urology
    Excerpt

    PURPOSE: Circumcision has traditionally been regarded as primary therapy for persistent phimosis in boys. Recently groups in Europe and Australia have advocated the use of topical steroids as conservative treatment in children. We report our experience with this approach. MATERIALS AND METHODS: Between July 1997 and February 1998, 25 boys with a mean age of 8.3 years who presented to our clinic with phimosis were started on a topical steroid. After counseling the family regarding treatment options we prescribed a 1-month course of 0.05% betamethasone cream applied twice daily. RESULTS: Of the 25 patients 24 completed the treatment and were evaluated. A total of 16 boys (67%) had a normal appearing foreskin that was easily retracted, while in the remaining 8 the outcome was unsuccessful and circumcision was scheduled. CONCLUSIONS: Our study demonstrates that the application of topical steroids is a viable alternative for treating phimosis in children. Appropriate candidates for this therapy include boys older than 3 years who have persistent phimosis and no evidence of infection.

    Title A Pc12 Variant Lacking Regulated Secretory Organelles: Aberrant Protein Targeting and Evidence for a Factor Inhibiting Neuroendocrine Gene Expression.
    Date July 1999
    Journal Journal of Neurochemistry
    Excerpt

    A variant of the PC12 pheochromocytoma cell line (termed A35C) has been isolated that lacks regulated secretory organelles and several constituent proteins. Northern and Southern blot analyses suggested a block at the transcriptional level. The proprotein-converting enzyme carboxypeptidase H was synthesised in the A35C cell line but was secreted by the constitutive pathway. Transient transfection of A35C cells with cDNAs encoding the regulated secretory proteins dopamine beta-hydroxylase and synaptotagmin I resulted in distinct patterns of mistargeting of these proteins. It is surprising that hybrid cells created by fusing normal PC12 cells with A35C cells exhibited the variant phenotype, suggesting that A35C cells express an inhibitory factor that represses neuroendocrine-specific gene expression.

    Title Regulation of the Macrophage Vacuolar Atpase and Phagosome-lysosome Fusion by Histoplasma Capsulatum.
    Date June 1999
    Journal Journal of Immunology (baltimore, Md. : 1950)
    Excerpt

    Histoplasma capsulatum (Hc) maintains a phagosomal pH of about 6.5. This strategy allows Hc to obtain iron from transferrin, and minimize the activity of macrophage (Mo) lysosomal hydrolases. To determine the mechanism of pH regulation, we evaluated the function of the vacuolar ATPase (V-ATPase) in RAW264.7 Mo infected with Hc yeast or the nonpathogenic yeast Saccharomyces cerevisae (Sc). Incubation of Hc-infected Mo with bafilomycin, an inhibitor of the V-ATPase, did not affect the intracellular growth of Hc, nor did it affect the intraphagosomal pH. In contrast, upon addition of bafilomycin, phagosomes containing Sc rapidly changed their pH from 5 to 7. Hc-containing phagosomes had 5-fold less V-ATPase than Sc-containing phagosomes as quantified by immunoelectron microscopy. Furthermore, Hc-containing phagosomes inhibited phagolysosomal fusion as quantified by the presence of acid phosphatase, accumulation of LAMP2, and fusion with rhodamine B-isothiocyanate-labeled dextran-loaded lysosomes. Finally, in Hc-containing phagosomes, uptake of ferritin was equivalent to phagosomes containing Sc, indicating that Hc-containing phagosomes have full access to the early "bulk flow" endocytic pathway. Thus, Hc yeasts inhibit phagolysosomal fusion, inhibit accumulation of the V-ATPase in the phagosome, and actively acidify the phagosomal pH to 6.5 as part of their strategy to survive in Mo phagosomes.

    Title Quantification of Axonal Damage in Traumatic Brain Injury: Affinity Purification and Characterization of Cerebrospinal Fluid Tau Proteins.
    Date February 1999
    Journal Journal of Neurochemistry
    Excerpt

    Diffuse axonal injury is a primary feature of head trauma and is one of the most frequent causes of mortality and morbidity. Diffuse axonal injury is microscopic in nature and difficult or impossible to detect with imaging techniques. The objective of the present study was to determine whether axonal injury in head trauma patients could be quantified by measuring levels of CSF tau proteins. Tau proteins are structural microtubule binding proteins primarily localized in the axonal compartment of neurons. Monoclonal antibodies recognizing the form of tau found in the CSF of head trauma patients were developed by differential CSF hybridoma screening using CSF from head trauma and control patients. Clones positive for head trauma CSF tau proteins were used to characterize this form of tau and for ELISA development. Using the developed ELISA, CSF tau levels were elevated >1,000-fold in head trauma patients (mean, 1,519 ng/ml of CSF) when compared with patients with multiple sclerosis (mean, 0.014 ng/ml of CSF; p < 0.001), normal pressure hydrocephalus (nondetectable CSF tau), neurologic controls (mean, 0.031 ng/ml of CSF; p < 0.001), or nonneurologic controls (nondetectable CSF tau; p < 0.001). In head trauma, a relationship between clinical improvement and decreased CSF tau levels was observed. These data suggest that CSF tau levels may prove a clinically useful assay for quantifying the axonal injury associated with head trauma and monitoring efficacy of neuroprotective agents. Affinity purification of CSF tau from head trauma patients indicated a uniform cleavage of approximately 18 kDa from all six tau isoforms, reducing their apparent molecular sizes to 30-50 kDa. These cleaved forms of CSF tau consisted of the interior portion of the tau sequence, including the microtubule binding domain, as judged by cyanogen bromide digestion. Consistent with these data, CSF cleaved tau bound taxol-polymerized microtubules, indicating a functionally intact microtubule binding domain. Furthermore, epitope mapping studies suggested that CSF cleaved tau proteins consist of the interior portion of the tau sequence with cleavage at both N and C terminals.

    Title Disposable Bedpads for Incontinence: Predicting Their Clinical Leakage Properties Using Laboratory Tests.
    Date December 1998
    Journal Medical Engineering & Physics
    Excerpt

    A multi-centre project has been run to identify laboratory tests capable of predicting the leakage performance of disposable incontinence bedpads. Each of 95 subjects tested each of six products for a week in turn and reported whether or not they and/or their carers found the leakage performance of each product acceptable. In addition, carers noted the severity with which individual used bedpads had leaked so that, when they had been weighed, their leakage performance could be determined as a function of urine weight. These clinical data were compared with results from the 16 different laboratory tests used routinely for bedpad evaluation in three hospital laboratories. Each test was evaluated by seeing how well the data it yielded correlated with the clinical test data. No individual test was very successful at predicting the performance of bedpads when used as sole protection but a combination of an absorption capacity test and an absorption time test predicted the percentage of users/carers finding leakage performance acceptable, accurate to within +/- eight percentage points for all six test products. A different absorption capacity test proved most successful for bedpads used as back-up to body-worn products. It predicted the percentage of users/carers finding leakage performance acceptable, accurate to +/- five percentage points for all six products.

    Title Predicting the Leakage Performance of Small Bodyworn Disposable Incontinence Pads Using Laboratory Tests.
    Date January 1998
    Journal Medical Engineering & Physics
    Excerpt

    An international multi-centre project has been run to create an international standard for measuring the leakage performance of small, disposable incontinence pads for lightly incontinent women. One hundred and thirteen women tested batches of nine different incontinence pads of widely differing designs and noted the severity with which each individual used pad had leaked so that leakage performance could be determined as a function of urine weight. In addition, testers rated the overall leakage performance of each of the nine products on a five-point scale. These clinical data were compared with laboratory data from 153 different pad measurements, each of which was evaluated by seeing how well the data it yielded correlated with the clinical test data. A wetback test emerged as the clear winner. It usually predicted the clinical leakage performance of pads to an accuracy of +/- 10%. It involved applying 25 ml of 1% w/v saline to a pad and measuring how much escaped into a filter paper held against the wet pad for 1 min under a pressure of 1.5 kPa. Pads which released the least test fluid into the filter paper leaked least in the user tests. The method will be published as an ISO standard during 1997.

    Title Identification of Microtubule-associated Protein Tau Isoforms in Alzheimer's Paired Helical Filaments.
    Date September 1997
    Journal Brain Research Bulletin
    Excerpt

    AD66 proteins derived from sodium dodecylsulfate (SDS) insoluble paired helical filaments (PHF) were isolated from Alzheimer's brain using a purification procedure developed previously in this laboratory, and characterized by immunologic and chemical cleavage methods. AD66 proteins were immunoreactive with antibodies that recognize the amino terminal, tubulin-binding, and carboxy terminal domains of microtubule-associated protein tau indicating the presence of the entire tau sequence in AD66 proteins. These proteins were reactive with antibody 423 that binds to PHF but not human adult tau. Immunologic and chemical cleavage studies indicated that only two of the six tau isoforms were present in these proteins. AD66 proteins were comprised of tau proteins containing only three tubulin binding domains with either a 29 amino acid insert or no amino terminal insert. For comparative purposes, SDS soluble PHF-tau (A68 proteins) was purified from Alzheimer's brains and normal adult tau purified from control brains. Antibody Alz-50 was immunoreactive with PHF-tau or normal tau regardless of alkaline phosphatase treatment while immunoreactivity was only observed with dephosphorylated AD66 proteins. A second phosphorylated epitope on AD66 proteins but not PHF-tau or normal tau proteins was demonstrated with antibody PHF9. These data suggest that AD66 proteins represent a more phosphorylated form of tau than PHF-tau or normal tau proteins. Two-dimensional gel electrophoresis demonstrated that AD66 proteins have higher apparent molecular weights and lower pI values than normal tau, differences possibly due to the greater phosphorylation observed in these proteins.

    Title Active and Passive Compliance of the Fetal Bovine Bladder.
    Date September 1997
    Journal The Journal of Urology
    Excerpt

    PURPOSE: Others have shown that the fetal bovine bladder is relatively noncompliant. Previous studies on compliance of fetal bovine bladders have demonstrated that the youngest fetal bladders had lowest and the oldest fetal bladders (near full-term) had greatest compliance. Our study was designed to determine the level of participation of active tension in the compliance of fetal bladders during gestation. MATERIALS AND METHODS: Fetal bovine bladders were obtained immediately after maternal harvest and crown-to-rump length was measured to determine gestational age. The fetus was inspected for genitourinary anomalies and the bladder was immediately placed in chilled M199 media. Strips (1 x 0.5 cm.) were excised from the anterior sagittal plane of the bladder and subjected to length-tension analysis in oxygenated Tyrode's buffer at 37C. Tension was measured using a force transducer and length was increased using a micropositioner. Compliance refers to the length-tension studies performed in normal Tyrode's solution and consists of a combination of active (smooth muscle tone) and passive properties. Passive compliance refers to length-tension studies performed after inactivation of bladder smooth muscle tone. Compliance with muscle tone intact was determined by incrementally stretching the strips to twice resting length in physiological buffer and then permitting them to return to resting length. Passive compliance with muscle tone ablated was determined in the same fashion after overnight incubation in calcium-free Tyrode's buffer in the presence of 5 mM. egtazic acid and 10 mM. sodium azide. An exponential function was fit to the normalized length-tension curves, where the exponential coefficient (EC) is numerically inversely proportional to compliance. RESULTS: Passive compliance was greatest in the youngest bladders (EC = 0.5 in the first trimester) and gradually decreased with increasing fetal age (EC = 1.2 in the third trimester). Active compliance demonstrated the opposite pattern, since the younger bladders were more stiff (EC = 2.1 in the first and 1.6 in the third trimesters). CONCLUSIONS: These studies demonstrate that passive compliance is greatest in the youngest bladders and progressively decreases with gestation. However, active smooth muscle tone is greatest in the youngest bladders and decreases with gestation. Thus, high active smooth muscle tone in the youngest fetal bladders results in relatively poor compliance of the early stage fetal bladder.

    Title Active Specific Immunotherapy of Metastatic Melanoma with an Antiidiotype Vaccine: a Phase I/ii Trial of I-mel-2 Plus Saf-m.
    Date June 1997
    Journal Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology
    Excerpt

    PURPOSE: To determine the toxicity and immunologic activity of an antiidiotype melanoma vaccine that consists of monoclonal antibody I-Mel-2 (MELIMMUNE-2, IDEC Pharmaceuticals, La Jolla, CA) and an immunologic adjuvant SAF-m. PATIENTS AND METHODS: Twenty-six patients with metastatic melanoma, 17 of whom had previously received chemotherapy, were given 2 mg of I-Mel-2 and either 100 micrograms (n = 6) or 250 micrograms (n = 20) of SAF-m. Antiidiotype vaccine was given intramuscularly (IM) biweekly for 4 weeks, and then bimonthly until disease progression. Human antimurine antibodies (HAMA), anti-I-Mel-2 antibodies, and specific antibody (Ab)3 against the melanoma epitope mimicked by the vaccine were titrated before treatment, biweekly from weeks 4 to 12, and every 4 to 8 weeks thereafter. Computed tomographic (CT) scans of the chest, abdomen, and pelvis and magnetic resonance imaging (MRI) of the brain were obtained before and bimonthly during treatment to evaluate responses. RESULTS: Elevated titers of human antimouse antibodies and anti-I-Mel-2 antibodies were associated with clinical antitumor effect (P = .02 and P = .05, respectively). Ab3 was absent in most patients, but was found in the best clinical responder. Fever, myalgias/arthralgias, fatigue, nausea, and headaches were the most common toxicities. Grade III myalgias/arthralgias and headaches required dose reduction of SAF-m in eight patients at the 250-microgram dose. No treatment-related death occurred. Six patients had an antitumor effect: one complete response in liver and lung, two minor responses, and three stable disease. The patient with a complete response has survived nearly 5 years. CONCLUSION: I-Mel-2 antiidiotype vaccine was safe, tolerated best at the 100-microgram dose of SAF-m, and had immunologic and clinical activity.

    Title Monoclonal Antibody Phf-9 Recognizes Phosphorylated Serine 404 of Tau Protein and Labels Paired Helical Filaments.
    Date May 1997
    Journal Journal of Neuroscience Research
    Excerpt

    Paired helical filaments (PHFs) purified from alzheimer's brain consist of hyperphosphorylated microtubule-associated protein tau. In PHF, phosphorylation occurs at ser/thr tau residues. Several of these ser/thr phosphorylation sites lie immediately C-terminal to the tau tubulin binding domain. The C-terminal ser396 to thr413 tau region contains two or more phosphorylated residues and eight possible ser/thr phosphorylation sites. Immunologic studies and mass spectroscopy have identified ser396 as one of the phosphorylation sites but identification of more C-terminal phosphorylated residues has been hampered by the lack of monoclonal antibodies (Mabs) that recognize defined epitopes in this region. We have raised Mabs against PHF purified from Alzheimer's brain. One of these Mabs, PHF-9, showed phosphorylation-dependent binding to purified PHF and recognized a phosphorylated epitope in the C-terminal portion of cyanogen bromide-digested PHF. Epitope mapping studies employing synthetic tau phosphopeptides indicated that PHF-9 labeled a 13-mer tau peptide phosphorylated at ser404 but not the corresponding non-phosphorylated peptide. PHF-9 demonstrated no immunoreactivity with a synthetic peptide phosphorylated at ser396 indicating that the PHF-9 epitope is C-terminal to ser396. In conclusion, the present study describes a Mab, PHF-9, which recognizes phosphorylated ser404 of tau independently of phosphorylated ser396 and indicates that tau ser404 is phosphorylated in PHF.

    Title Fumarase C Activity is Elevated in Response to Iron Deprivation and in Mucoid, Alginate-producing Pseudomonas Aeruginosa: Cloning and Characterization of Fumc and Purification of Native Fumc.
    Date March 1997
    Journal Journal of Bacteriology
    Excerpt

    We report the discovery of fumC, encoding a fumarase, upstream of the sodA gene, encoding manganese superoxide dismutase, in Pseudomonas aeruginosa. The fumC open reading frame, which terminates 485 bp upstream of sodA, contains 1,374 bp that encode 458 amino acids. A second 444-bp open reading frame located between fumC and sodA, called orfX, showed no homology with any genes or proteins in database searches. A fumarase activity stain revealed that P. aeruginosa possesses at least two and possibly three fumarases. Total fumarase activity was at least approximately 1.6-fold greater in mucoid, alginate-producing bacteria than in nonmucoid bacteria and decreased 84 to 95% during the first 5 h of aerobic growth, followed by a rapid rise to maximum activity in stationary phase. Bacteria exposed to the iron chelator 2,2'-dipyridyl, but not ferric chloride, demonstrated an increase in fumarase activity. Mucoid bacteria produced approximately twofold-higher levels of the siderophores pyoverdin and pyochelin than nonmucoid bacteria. Northern blot analysis revealed a transcript that included fumC, orfX, and sodA, the amount of which was increased in response to iron deprivation. A P. aeruginosa fumC mutant produced only approximately 40% the alginate of wild-type bacteria. Interestingly, a sodA mutant possessed an alginate-stable phenotype, a trait that is typically unstable in vitro. These data suggest that mucoid bacteria either are in an iron-starved state relative to nonmucoid bacteria or simply require more iron for the process of alginate biosynthesis. In addition, the iron-regulated, tricarboxylic acid cycle enzyme fumarase C is essential for optimal alginate production by P. aeruginosa.

    Title An Operon Containing Fumc and Soda Encoding Fumarase C and Manganese Superoxide Dismutase is Controlled by the Ferric Uptake Regulator in Pseudomonas Aeruginosa: Fur Mutants Produce Elevated Alginate Levels.
    Date March 1997
    Journal Journal of Bacteriology
    Excerpt

    The activities of fumarase- and manganese-cofactored superoxide dismutase (SOD), encoded by the fumC and sodA genes in Pseudomonas aeruginosa, are elevated in mucoid, alginate-producing bacteria and in response to iron deprivation (D. J. Hassett, M. L. Howell, P. A. Sokol, M. L. Vasil, and G. E. Dean, J. Bacteriol. 179:1442-1451, 1997). In this study, a 393-bp open reading frame, fagA (Fur-associated gene), was identified immediately upstream of fumC, in an operon with orfX and sodA. Two iron boxes or Fur (ferric uptake regulatory protein) binding sites were discovered just upstream of fagA. Purified P. aeruginosa Fur caused a gel mobility shift of a PCR product containing these iron box regions. DNA footprinting analysis revealed a 37-bp region that included the Fur binding sites and was protected by Fur. Primer extension analysis and RNase protection assays revealed that the operon is composed of at least three major iron-regulated transcripts. Four mucoid fur mutants produced 1.7- to 2.6-fold-greater fumarase activity and 1.7- to 2.3-greater amounts of alginate than wild-type organisms. A strain devoid of the alternative sigma factor AlgT(U) produced elevated levels of one major transcript and fumarase C and manganase-cofactored SOD activity, suggesting that AlgT(U) may either play a role in regulating this transcript or function in some facet of iron metabolism. These data suggest that the P. aeruginosa fagA, fumC, orfX, and sodA genes reside together on a small operon that is regulated by Fur and is transcribed in response to iron limitation in mucoid, alginate-producing bacteria.

    Title Resorption-cycle-dependent Polarization of Mrnas for Different Subunits of V-atpase in Bone-resorbing Osteoclasts.
    Date October 1996
    Journal Molecular Biology of the Cell
    Excerpt

    Protein sorting in eukaryotic cells is mainly done by specific targeting of polypeptides. The present evidence from oocytes, neurons, and some other polarized cells suggests that protein sorting can be further facilitated by concentrating mRNAs to their corresponding subcellular areas. However, very little is known about the mechanism(s) involved in mRNA targeting, or how widespread and dynamic such mRNA sorting might be. In this study, we have used an in vitro cell culture system, where large multinucleated osteoclasts undergo continuous structural and functional changes from polarized (resorbing) to a nonpolarized (resting) stage. We demonstrate here, using a nonradioactive in situ hybridization technique and confocal microscopy, that mRNAs for several vacuolar H(+)-ATPase subunits change their localization and polarity in osteoclasts according to the resorption cycle, whereas mRNA for cytoplasmic carbonic anhydrase II is found diffusely located throughout the osteoclast during the whole resorption cycle. Antisense RNA against the 16-kDa or 60-kDa V-ATPase subunit inhibits polarization of the osteoclasts, as determined by cytoskeleton staining. Antisense RNA against carbonic anhydrase II, however, has no such effect.

    Title An Institutional Commitment to Pain Management.
    Date October 1995
    Journal Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology
    Excerpt

    PURPOSE: To share the development, implementation, and evaluation of a program called "An Institutional Commitment to Pain Management," which is based on the philosophy of organizational influence on pain management. METHODS: A tested pain education model was disseminated to 32 physician/nurse teams in settings throughout California, after which the 64 professionals returned to their institutions to serve as role models and catalysts to change the practice of pain management. Each team member completed a 39-item survey about knowledge and attitudes related to pain, which was developed by B.R.F. and colleagues, and also identified three goals for the implementation of course information. Precourse data also included administration of the knowledge and attitudes survey to participating physicians' and nurses' colleagues (10 physicians and 20 nurses per institution). Each team completed five chart audits using the pain audit tool (PAT), which was developed by B.R.F. and colleagues at the City of Hope National Medical Center. The PAT identifies how pain is managed currently at the institutional level. Final course evaluation 8 months after course completion included a summary of activities implemented by the teams as well as the factors that served as barriers and benefits to improve the quality of pain management. RESULTS: Two hundred seventy-two physicians and 629 nurses completed the survey about knowledge and attitudes related to pain, and 154 PATs were submitted. These results, as well as evaluation at the completion of the course, are discussed. CONCLUSION: The Institutional Commitment to Pain Management program is an evolving model that was developed to overcome barriers to pain relief by obtaining the commitment from institutions to improve the management of pain for their patients.

    Title Fatigue in Patients with Cancer Receiving Interferon Alpha.
    Date August 1995
    Journal Cancer Practice
    Excerpt

    Fatigue is the most frequently reported symptom of patients with cancer. The purpose of this study was to describe the experience of fatigue over time in patients with cancer receiving treatment with interferon alpha. Piper's Integrated Fatigue Model guided this study. A descriptive repeated-measures design was used. A convenience sample of 30 patients with malignant melanoma was drawn from a comprehensive cancer center in Southern California. Two instruments were used in data collection, the Symptom Distress Scale and the Piper Fatigue Scale. Study findings revealed descriptive data on patients' perceptions of the causes and remedies for fatigue while receiving active treatment for cancer. The pattern of fatigue was consistent over the five points of time during treatment, with the most extreme fatigue scores in the affective domain, followed by the sensory, temporal, total fatigue, and fatigue severity scores. The patterns and dimensions of fatigue provide implications for care of patients receiving interferon alpha, and for further investigation in the area of fatigue as a critical aspect of quality of life.

    Title Cloning and Functional Characterization Through Antisense Mapping of a Kappa 3-related Opioid Receptor.
    Date August 1995
    Journal Molecular Pharmacology
    Excerpt

    We have identified a putative opioid receptor from mouse brain (KOR-3), belonging to the G protein-coupled receptor family, that is distinct from the previously cloned mu, delta, and kappa 1 receptors. Assignment of the clone to the opioid receptor family derives from both structural and functional studies. Its predicted amino acid sequence is highly homologous to that of the other opioid receptors, particularly in many of the transmembrane regions, where long stretches are identical to mu, delta, and kappa 1 receptors. Both cyclazocine and nalorphine inhibit cAMP accumulation in COS-7 cells stably expressing the clone. Northern analysis shows that the mRNA is present in brain but not in a number of other organs. Southern analysis suggests a single gene encoding the receptor. A highly selective monoclonal antibody directed against the native kappa 3 receptor recognizes, in Western analysis, the clone expressed in COS-7 cells. The in vitro translation product is also labeled by the antibody. Additional clones reveal the presence of several introns, including one in the second extracellular loop and another in the first transmembrane region. Antisense studies with an oligodeoxynucleotide directed against a region of the second extracellular loop reveal a selective blockade of kappa 3 analgesia in vivo that is not observed with a mismatch oligodeoxynucleotide based upon the antisense sequence. The mu, delta, and kappa 1 analgesia is unaffected by this antisense treatment. Antisense mapping of the clone downstream from the splice site in the first transmembrane region reveals that six different antisense oligodeoxynucleotides all block kappa 3 analgesia. In contrast, only one of an additional six different antisense oligodeoxynucleotides directed at regions upstream from this splice site is effective. This strong demarcation between the two regions raises the possibility of splice variants of the receptor. An additional clone reveals an insert in the 3' untranslated region. In conclusion, the antibody and antisense studies strongly associate KOR-3 with the kappa 3-opioid receptor, although it is not clear whether it is the kappa 3 receptor itself or a splice variant.

    Title When Analgesia Leads to Constipation.
    Date May 1995
    Journal Nursing
    Title Managing Nausea.
    Date March 1995
    Journal Nursing
    Title Overcoming Sedation.
    Date March 1995
    Journal Nursing
    Title Ethical Issues in Pain Management at Home.
    Date March 1995
    Journal Journal of Palliative Care
    Excerpt

    This review of several studies from the authors' program of research supports the notion that the experience of pain, particularly in the home, has a profound effect not only on the patient, but on family and health care providers as well. Family caregivers revealed their private grief and burden when describing the physical suffering they witnessed. They faced the daily responsibility of making decisions regarding a loved one's pain, and the decisions often resulted in ethical conflicts. Caregivers generally felt ill-prepared for the administration of pain medication. They struggled to balance the need for medications to relieve pain against the perceived unwanted side effects and fear of addiction. These studies also demonstrate that a concerted effort must be made by health care providers to support the pain management role of family caregivers. By listening, being available, making pain management a priority, and reinforcing appropriate pain management principles, health care professionals help sustain family caregivers in carrying out their anguishing and unrelenting task.

    Title Phase Ii Study of Low Dose Cyclophosphamide and Intravenous Interleukin-2 in Metastatic Renal Cancer.
    Date December 1994
    Journal Investigational New Drugs
    Excerpt

    Thirteen patients with metastatic renal cancer were treated in a phase II trial with interleukin-2, 21.6 million IU/m2 intravenously daily for five days on two consecutive weeks, starting 3 days after the administration of low dose cyclophosphamide 350 mg/m2 intravenously. Treatment cycles were repeated every 21 days. No responses were seen (95% Confidence Interval: 0-22%). The most common toxicities were fever, fatigue, hypotension, nausea/emesis, and myalgia/arthralgia. There were 11 episodes of Grade III toxicity including Grade III hypotension in 7 patients. Because of the significant toxicity and the lack of observed response, the study was discontinued. Cyclophosphamide and interleukin-2 at the dose and schedule used in this study has considerable toxicity and is unlikely to improve on response rates previously seen with other IL-2 based regimens in metastatic renal cancer.

    Title Protein Splicing Elements: Inteins and Exteins--a Definition of Terms and Recommended Nomenclature.
    Date May 1994
    Journal Nucleic Acids Research
    Title Alzheimer's Paired Helical Filaments: Amyloid Precursor Protein Epitope Mapping.
    Date April 1994
    Journal Brain Research Bulletin
    Excerpt

    Paired helical filaments (PHF) were electrophoretically purified and solubilized from Alzheimer's neurofibrillary tangles and consisted of a primary 66 kDa protein on SDS-PAGE analysis. A panel of antibodies raised against restricted regions of the beta-amyloid precursor protein (APP) were employed for epitope mapping studies of this 66 kDa PHF protein. Western blot studies revealed that C-terminal APP antibodies were immunoreactive with the 66 kDa PHF protein. Further analysis revealed that only antisera raised against peptides that include the beta/A4-amyloid region within the C-terminal portion of APP were immunoreactive with PHF proteins. These data complement previous immunocytochemical studies which indicated that C-terminal APP antibodies preferentially label PHF-containing neurofibrillary tangles in Alzheimer's brain. The present data suggest a similarity of secondary or tertiary structure between beta/A4-amyloid and PHF which accounts for the cross-reactivity of beta/A4-amyloid antibodies with PHF proteins.

    Title Cloning and Functional Expression of a Tetrabenazine Sensitive Vesicular Monoamine Transporter from Bovine Chromaffin Granules.
    Date March 1994
    Journal Febs Letters
    Excerpt

    Using oligonucleotide primers derived from the vesicular monoamine transporters sequences, a cDNA predicted to encode the bovine chromaffin granule amine transporter has been cloned (b-VMAT2). Surprisingly, its structure is more similar to the rat brain transporter (VMAT2), than to the rat adrenal counterpart (VMAT1). Unlike rat VMAT1, bovine VMAT2 appears to be expressed both in the adrenal medulla and the brain, as judged by Northern analysis. After modification/deletion of the seven amino acids at the N-terminus of the protein it was expressed in a functional form. The order of affinity of the bovine VMAT2 transporter to substrates is: serotonin > dopamine = norepinephrine > epinephrine. Also, the recombinant bovine adrenal transporter is highly sensitive to tetrabenazine, in sharp contrast to the rat adrenal transporter. The findings indicate, therefore, a clear species variation in which structure and function of the bovine adrenal transporter resemble the rat brain protein, while its tissue distribution is distinct from both types of rat proteins. In addition, the predicted protein sequence is identical to the experimentally determined N-terminus sequence of the purified vesicular amine transporter [Stern-Bach et al. (1992) Proc. Natl. Acad. Sci. USA 89, 9730-9733].

    Title Cloning and Sequence Analysis of an H(+)-atpase-encoding Gene from the Human Dimorphic Pathogen Histoplasma Capsulatum.
    Date February 1994
    Journal Gene
    Excerpt

    A gene related to the PMA1 gene from Saccharomyces cerevisiae was isolated from the pathogenic human dimorphic fungus, Histoplasma capsulatum, using fungal-specific oligodeoxyribonucleotide (oligo) probes. This gene has been given the name Hc-PMA1. The structural organization of Hc-PMA1 consists of three exons (375, 2329 and 44 bp) and two introns (115 and 116 bp). The nucleotide sequence predicts an H(+)-ATPase-related protein of 916 amino acids (aa). Comparison of the deduced aa sequence to that of Neurospora crassa and S. cerevisiae (PMA1) plasma membrane H(+)-ATPases showed a greater similarity to that from N. crassa (85% identity). Furthermore, the two introns in the Hc-PMA1 gene interrupt the coding region in the precise locations determined for two of the four N. crassa Nc-PMA introns. H. capsulatum intron 1 contains two repeat motifs, d(TA)16 and d(TG)10, each potentially capable of forming non-B DNA structures. Northern analysis of H. capsulatum total RNA indicated that the Hc-PMA1-specific mRNA is approx. 3.3 kb in size, in agreement with the predicted size of the gene.

    Title Preliminary Results of Laser Tissue Welding in Extravesical Reimplantation of the Ureters.
    Date February 1994
    Journal The Journal of Urology
    Excerpt

    One exciting potential use of laparoscopic technology is the extravesical reimplantation of the ureters. We have assessed the efficacy of laser-activated fibrinogen solder to close vesical muscle flaps over submucosal ureters (Lich-Gregoir technique) in a canine model. Four dogs were subjected to unilateral flap closures via a protein solder (indocyanine green and fibrinogen) applied to the bladder serosa and exposed to 808 nm. continuous wave diode laser energy. Contralateral reimplantation was performed using 4-zero vicryl muscle flap closures (controls). At 7, 14 and 28 days postoperatively, intravenous pyelograms confirmed bilateral ureteral patency. At intravesical pressures above 100 cm. H2O, there was no evidence of wound disruption in either group. Nondisrupted wound closures were sectioned and strained until ultimate breakage to determine tensile strength. At each study interval the laser-welded closures withstood greater stress than the controls. Although these data represent single tissue samples and are not amenable to statistical analysis, laser-welded closures appeared to be stronger at each study interval. In conclusion, laser-welded vesical wound closures appear at least as strong as suture closures in the canine model.

    Title Saccharomyces Cerevisiae Expression of Exogenous Vacuolar Atpase Subunits B.
    Date October 1993
    Journal Biochimica Et Biophysica Acta
    Excerpt

    The precise function of subunit B of the vacuolar H(+)-ATPase class is unknown, but it is essential for proton pumping. We have previously reported the DNA sequence and predicted protein sequence of the vacuolar ATPase subunit B for Candida tropicalis (Gu, H.H., Gallagher, M.J., Rupkey, S. and Dean, G.E. (1990) Nucleic Acids Res. 18, 7446). When the Candida gene was expressed in a Saccharomyce cerevisiae delta vat2 mutant from which the homologous gene had been deleted, viability and vacuolar acidification was restored to apparently wild-type levels. The predicted identity between these two proteins is 90%. We have searched for vacuolar ATPase subunits B from other species that might show a difference in function, when expressed in yeast, relative to the endogenous gene. We have cloned an apparently full-length 1.8-kb bovine subunit B cDNA from adrenal medulla that is about 1 kb shorter than the previously reported bovine brain cDNA (Puopolo, K., Kumamoto, C., Adachi, I., Magner, R. and Forgac, M. (1992) J. Biol. Chem. 267, 3696-3706; Nelson, R.D., Guo, X.L., Masood, K., Brown, D., Kalkbrenner, M. and Gluck, S. (1992) Proc. Natl. Acad. Sci. USA 89, 3541-3545), but nearly identical throughout the coding nucleotide and protein sequences; it is only 74% identical to the Saccharomyces subunit B protein sequence. Upon expression of this cDNA in two different delta vat2 deletion strains, the bovine cDNA restored function only partially, as judged by both viability at high pH and vacuolar acidification. Current work is aimed at determining which regions of the bovine protein require alteration in order to fully restore the delta vat2 strain to wild-type acidification, with the eventual goal of identifying interactive residues between subunit B and other proteins required for pump function.

    Title Peptide Splicing in the Vacuolar Atpase Subunit A from Candida Tropicalis.
    Date May 1993
    Journal The Journal of Biological Chemistry
    Excerpt

    Subunit A of the vacuolar proton pump appears to be responsible for the ATP hydrolysis which is coupled to the pumping of protons into a variety of intracellular acid compartments, including the fungal vacuole. We report here the cloning and sequence determination of the gene encoding subunit A from Candida tropicalis. Southern blot hybridization analysis indicates that there is a single gene which encodes this protein. The gene contains a single intron at the extreme 5'-end of the coding region. The gene is predicted to encode a polypeptide of 1088 residues with a calculated molecular mass of 119,019 daltons, yet the mature polypeptide appears to be approximately 67 kDa, indicating that this protein probably undergoes the same sort of processing that is evidenced in the homologous protein from Saccharomyces cerevisiae in which an approximately 50-kDa polypeptide (the spacer) is spliced out of the mature protein. The Candida gene, with and without this middle portion, has been expressed in S. cerevisiae and found to restore a Saccharomyces subunit A deletion mutant (tfp1-delta 8) to apparently wild-type growth at pH 7.6, and normal vacuolar acidification. The peptide sequence of the two predicted mature ends is very similar to the sequences of the analogous proteins from Daucus carota, S. cerevisiae, and Neurospora crassa (60.5, 87.4, and 72.9% identity, respectively), but the middle portion bears only very limited homology with the Saccharomyces protein sequence. Processing of the gene product occurs in S. cerevisiae, Escherichia coli, and in rabbit reticulocyte-mediated in vitro translation, indicating that the excision is probably autocatalytic. The limited sequence identity seen between the Saccharomyces and Candida spacer domains may considerably narrow the functionally important regions responsible for the excision event.

    Title Vaginal Replacement in Children.
    Date August 1992
    Journal The Journal of Urology
    Excerpt

    Between 1980 and 1990, 17 patients underwent total vaginal replacement at our hospital. The majority of these patients presented with müllerian failure or gender reassignment for intersex. Colon vaginal replacement was done in 15 patients and small bowel was used in 2. Complications included prolapse in 2 patients and stenosis in 2. Of the 17 patients 4 are married, 10 are sexually active, only 1 reports dyspareunia and 1 requires home self-dilation.

    Title Structure and Expression of Subunit A from the Bovine Chromaffin Cell Vacuolar Atpase.
    Date January 1992
    Journal Febs Letters
    Excerpt

    Subunit A of the vacuolar H(+)-ATPase class is thought to be responsible for the ATP hydrolysis which drives proton-pumping. We report here the cloning and sequence determination of the first mammalian cDNA encoding a bovine vacuolar ATPase subunit A from an adrenal medulla cDNA library. Northern blots of bovine adrenal medulla RNA reveal a message of approximately 3.8 kb. The predicted peptide sequence, consisting of 618 amino acids with a calculated molecular weight of 68397 daltons, is similar to the sequences of the three known subunit A proteins. beta-Galactosidase-subunit A fusion proteins were immuno-decorated by an antiserum raised to the subunit A protein from corn coleoptile vacuoles.

    Title Complications of Urinary Tract Reconstruction.
    Date November 1991
    Journal The Urologic Clinics of North America
    Excerpt

    Urinary tract reconstruction has benefited a vast number of patients with dysfunctional lower urinary tracts caused by congenital abnormalities, previous surgery, or both. Reconstructive efforts have been innovative and continue to evolve. With this evolution, new complications continue to appear, and in order to minimize the risk to the patient, we must recognize our previous lessons. Appropriate patient selection is essential in achieving a successful outcome in this group. The patient's neurologic status, urologic anatomy, renal function, and motivation are also important factors in choosing the appropriate patient and correct surgical approach. Close follow-up remains the single most important element in assuring long-term well-being for most of these patients.

    Title Gene and Derived Peptide Sequences for C. Tropicalis Vacuolar Atpase Subunit B.
    Date January 1991
    Journal Nucleic Acids Research
    Title Hyperpurification of Paired Helical Filaments Reveals Elevations in Hydroxyproline Content and a Core Structure Related Peptide Fragment.
    Date January 1990
    Journal Progress in Clinical and Biological Research
    Excerpt

    We have subjected conventionally-purified Alzheimer's paired helical filaments (PHF) to electrophoresis in a Tris/borate/SDS buffer and obtained the separation of PHF core protein(s) (PHFi) from solubilized PHF-associated proteins (PHFs). Electron microscopy revealed intact PHF structures before and after this separation, but no evidence of any other structures in the PHFi fraction. The percent mass of hydroxyproline and glycine increased in the PHFi fraction after 4.5 hr of electrophoresis to account for 5.8% and 13.6% of the total mass, respectively. ELISA data confirmed that our PHFi and PHFs fractions were reactive with several putative PHF-specific antibodies. These data suggest that inappropriate hydroxylation of proline residues occurs in precursor PHF protein(s), resulting in the polymerization and subsequent insolubility of PHF in brain regions affected with Alzheimer's disease. Neurofibrillary tangles (NFT), one of the primary neuropathological features of Alzheimer's disease, are comprised of cytosolic bundles of uniform proteins which microscopically appear to be paired helical filaments (PHF). PHF are thought to be responsible for the cellular necrosis associated with the clinical symptoms of Alzheimer's disease (Dayan, 1970; Hirano and Zimmerman, 1962). Optical reconstruction of PHF has recently indicated that the true structure is more accurately described as a twisted ribbon of 30 A in the axial direction (Wischik et al., 1988). Immunological studies have suggested that tubulin (Grundke-Iqbal et al., 1979), microtubule associated proteins (Grundke-Iqbal et al., 1986; Kosik et al., 1986; Wood et al., 1986; Ksiezak-Reding et al., 1987), intermediate filaments (Yen et al., 1983), neurofilaments (Anderton et al., 1982), and ubiquitin (Mori et al., 1987; Perry et al., 1987), form part of the PHF core protein. To date, however, no study has been able to definitively show that any one of these purported PHF components is contained in the PHF core structure, rather than being non-covalently bound proteins or co-purifying contaminants. The present study extends previously published purification procedures, resulting in an isolated stable PHF core structure which is indistinguishable from previously published descriptions of PHF. The amino acid composition (Bidlingmeyer et al., 1984) of the PHF core structure appears to include hydroxyproline, an amino acid not commonly found in cytosolic proteins. We also demonstrate that some monoclonal antibodies previously raised against semi-purified PHF recognize determinants which are not related to the PHF core structure but rather recognize PHF-associated proteins or contaminants of the purification process.

    Title Purification and Solubilization of Paired Helical Filaments from Alzheimer Brains.
    Date January 1990
    Journal Journal of Neurochemistry
    Excerpt

    The purpose of the present study was to develop a purification and solubilization method, compatible with current amino acid sequencing techniques, for paired helical filaments (PHFs) derived from patients with Alzheimer's disease. We have developed a mild procedure that subjects conventionally isolated PHFs to Tris/borate/sodium dodecyl sulfate/2-mercaptoethanol electrophoresis and results in the separation of the relatively insoluble PHF structures from both copurifying contaminating proteins and solubilized PHF-associated proteins. At the end of 4.5 h of electrophoresis, the purified insoluble fraction had an amino acid composition that was invariant during subsequent electrophoresis. Electron microscopy revealed an intact PHF structure before and after electrophoresis but no evidence of any other structures in the insoluble fraction, a result consistent with the removal of PHF-associated proteins from the filament structure. Isolated insoluble filament structures displayed an enhanced immunoreactivity with antibodies raised against purified PHFs in other laboratories, when compared with the fraction not subjected to electrophoresis in enzyme-linked immunosorbent assays. Solubilization of the relatively insoluble PHFs was accomplished by extending the time of electrophoresis beyond the 4.5 h required for purification. Additional electrophoresis for 34.5 h solubilized 88% of the purified, relatively insoluble PHFs. This resulted in the identification of four major protein bands between Mr values of approximately 50,000 and 70,000 on sodium dodecyl sulfate-polyacrylamide electrophoresis gel analysis, with a predominant band with an Mr of approximately 66,000. A slow fragmentation of the PHF ultrastructure occurred during this time, as judged by electron microscopy. This purification technique will permit the isolation of consistently reproducible protein fragments from solubilized PHFs, which may be used for subsequent sequence analysis.

    Title Analysis of Endosome and Lysosome Acidification in Vitro.
    Date April 1989
    Journal Methods in Enzymology
    Title An Immunoreactive 8-azido Atp-labeled Protein Common to the Lysosomal and Chromaffin Granule Membrane.
    Date February 1989
    Journal Biochimica Et Biophysica Acta
    Excerpt

    The H+-ATPases of eukaryotic cell organelles, including the rat liver lysosomal (tritosomal) H+-ATPase and the bovine chromaffin granule ATPase, exhibit similarities in function, substrate requirements, and inhibitor responses. We have explored the possibility that these pumps also exhibit immunological similarities, and that common determinants may be present on polypeptides important to function, such as ATP binding. Toward this end, antibodies were produced in rabbits against a highly purified, detergent-solubilized and fractionated chromaffin granule proton pump preparation. This antibody reacted with a 70-80 kDa protein of the lysosomal membrane on Western blots. We have previously shown that photolysis with 8-azido-ATP inhibits lysosomal N-ethylmaleimide-sensitive, vanadate-, ouabain- and oligomycin-insensitive ATP hydrolysis and H+ transport, with concomitant labeling of a 70-80 kDa membrane protein, amongst others. Here, we report that the photolysis with 8-azido-ATP also leads to inhibition of chromaffin granule H+ pump function and pump-related ATP hydrolysis, with concomitant N-ethylmaleimide-sensitive, ATP-protectable, 8-azido-[alpha-32P]ATP labeling. The anti-chromaffin granule antibody reacts with an approx. 70 kDa protein of the chromaffin granule and the lysosome. This raises the possibility that the 70 kDa 8-azido-ATP-reactive, immunologically similar proteins may play a similar role in pump function such as ATP binding and/or hydrolysis in these organelles.

    Title Identification of the M-ring Protein of the Flagellar Motor of Salmonella Typhimurium.
    Date December 1987
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    The M ring is a substructure of the flagellar basal body of bacteria, which lies in the cytoplasmic membrane and is therefore close to the site where the energy of the transmembrane proton potential is converted into mechanical work of rotation of the motor. The protein from which this ring is constructed has not been identified. Flagellar hook-basal body complexes from Salmonella typhimurium were used as the immunogen for the preparation of monoclonal antibodies. An antibody obtained was directed against a major basal-body component, a 65-kDa protein that from mutant studies has been assigned as the product of the flaAII.1 gene. By immunoelectron microscopy, the antibody was observed to bind the innermost feature of the basal body: the cytoplasmic-facing surface of the M ring. We conclude that the 65-kDa protein is a component--probably the main component--of this important substructure of the flagellar motor.

    Title Hydrodynamic Properties of the Chromaffin Granule Hydrogen Ion Pumping Adenosinetriphosphatase.
    Date September 1987
    Journal Biochemistry
    Excerpt

    We have determined the hydrodynamic properties of detergent-solubilized ATPase, which is coupled to H+ pumping in bovine adrenal chromaffin granules, by sedimentation equilibrium centrifugation and gel permeation chromatography. The protein solubilized with detergent containing phosphatidylserine sediments as a particle of 264,000 daltons and partial specific volume 0.829 cm3/g. Assuming a protein v of 0.73 and using the v measured for detergent and lipid mixed micelles of 0.93 cm3/g, we calculated that the protein component has a mass of 134,000 daltons and that the equivalent of approximately 1.5 micelles of detergent are bound per particle. The particle exhibits a Stokes radius of 43 A, which, together with the calculated particle volume, indicates an axial ratio close to 1. We conclude that the ATPase is an intrinsic membrane protein with a structure very different from that of mitochondrial F1F0 ATPase.

    Title Characterization of Native and Reconstituted Hydrogen Ion Pumping Adenosinetriphosphatase of Chromaffin Granules.
    Date November 1986
    Journal Biochemistry
    Excerpt

    The ATP-dependent H+ pump from adrenal chromaffin granules is, like the platelet-dense granule H+ pump, essentially insensitive to the mitochondrial ATPase inhibitors sodium azide, efrapeptin, and oligomycin and also insensitive to vanadate and ouabain, agents that inhibit the Na+,K+-ATPase. The chromaffin granule H+ pump is, however, sensitive to low concentrations of NEM (N-ethylmaleimide) and Nbd-Cl (7-chloro-4-nitro-2,1,3-benzoxadiazole). These transport ATPases may thus belong to a new class of ATP-dependent ion pumps distinct from F1F0-and phosphoenzyme-type ATPases. Comparisons of ATP hydrolysis with ATP-dependent serotonin transport suggest that approximately 80% of the ATPase activity in purified chromaffin granule membranes is coupled to H+ pumping. Most of the remaining ATPase activity is due to contaminating mitochondrial ATPase and Na+,K+-ATPase. When extracted with cholate and octyl glucoside, the H+ pump is solubilized in a monodisperse form that retains NEM-sensitive ATPase activity. When reconstituted into proteoliposomes with crude brain phospholipid, the extracted enzyme recovers ATP-dependent H+ pumping, which shows the same inhibitor sensitivity and nucleotide dependence as the native pump. These data demonstrate that the predominant ATP hydrolase of chromaffin granule membrane is also responsible for ATP-driven amine transport and granule acidification in both native and reconstituted membranes.

    Title Three-dimensional Structure of Endosomes in Bhk-21 Cells.
    Date June 1986
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    The organization of the endosome compartment in BHK-21 cells was studied by using horseradish peroxidase as a fluid-phase marker and Semliki Forest virus as an adsorptive marker. Stereo pairs of semithin sections (0.2-0.5 micron) and computer-aided reconstruction and tracing of serial thin sections (CARTOS) were used to obtain three-dimensional images of the labeled compartments. Two types of labeled organelles could be observed: small vesicles and tubules (approximately equal to 50 nm in diameter) and large complex structures consisting of central vesicular elements (with diameters up to 0.5 micron) and associated systems of radiating tubules. The large endosomes were located either in the peripheral cytoplasm or in the perinuclear region, and, importantly, they existed as independent organelles and not as an interconnected reticulum. Each endosomal vacuole had two to seven tubules oriented in random directions from the central vesicle. The tubules were 60-100 nm in diameter and up to 4 micron in length. Morphometric estimates indicated that 60-70% of the endosomal membrane was in the tubules, in contrast to 30-40% of the volume. No structural continuity between endosomes and Golgi cisternae was observed, although elements of the two systems were frequently found in close proximity.

    Title Nucleotide Sequence of the Escherichia Coli Motb Gene and Site-limited Incorporation of Its Product into the Cytoplasmic Membrane.
    Date May 1986
    Journal Journal of Bacteriology
    Excerpt

    The motB gene product of Escherichia coli is an integral membrane protein required for rotation of the flagellar motor. We have determined the nucleotide sequence of the motB region and find that it contains an open reading frame of 924 nucleotides which we ascribe to the motB gene. The predicted amino acid sequence of the gene product is 308 residues long and indicates an amphipathic protein with one major hydrophobic region, about 22 residues long, near the N terminus. There is no consensus signal sequence. We postulate that the protein has a short N-terminal region in the cytoplasm, an anchoring region in the membrane consisting of two spanning segments, and a large cytoplasmic C-terminal domain. By placing motB under control of the tryptophan operon promoter of Serratia marcescens, we have succeeded in overproducing the MotB protein. Under these conditions, the majority of MotB was found in the cytoplasm, indicating that the membrane has a limited capacity to incorporate the protein. We conclude that insertion of MotB into the membrane requires the presence of other more hydrophobic components, possibly including the MotA protein or other components of the flagellar motor. The results further reinforce the concept that the total flagellar motor consists of more than just the basal body.

    Title Serotonin Transport by Platelet Plasma and Granule Membranes.
    Date March 1986
    Journal Annals of the New York Academy of Sciences
    Title Purification and Characterization of the Flagellar Hook-basal Body Complex of Salmonella Typhimurium.
    Date April 1985
    Journal Journal of Bacteriology
    Excerpt

    The hook-basal body complex of Salmonella typhimurium, a major component of its flagellar apparatus, was subjected to detailed analysis by electron microscopy and gel electrophoresis. The study was facilitated by the development of an improved protocol for isolation of the complexes in high yield and purity. Nine proteins were identified with the structure. These proteins had apparent molecular weights of 65,000 (65K), 60K, 42K, 38K, 32K, 30K, 27K, 16K, and 14K. Small but reproducible shifts in the apparent molecular weights of specific proteins from conditionally nonflagellate mutants indicated the following gene-polypeptide correspondences: flaFV, 42K; flaFVI, 32K; flaFVII, 30K; flaFIX, 38K; flaAII.1, 65K. Several new morphological features of hook-basal body complexes were recognized, including a clawlike structure on the cytoplasm-proximal M ring and additional material at the cytoplasmic face of the M ring. Based on this study and the work of others, we suggest that the morphological features of the hook-basal body complex correspond to the following proteins: hook-filament junction, 60K; hook, 42K; rod, 30K and 32K; L ring and outer cylinder wall, 27K; P ring, 38K; S ring, unknown; M ring 65K.

    Title Gene Sequence and Predicted Amino Acid Sequence of the Mota Protein, a Membrane-associated Protein Required for Flagellar Rotation in Escherichia Coli.
    Date November 1984
    Journal Journal of Bacteriology
    Excerpt

    The motA and motB gene products of Escherichia coli are integral membrane proteins necessary for flagellar rotation. We determined the DNA sequence of the region containing the motA gene and its promoter. Within this sequence, there is an open reading frame of 885 nucleotides, which with high probability (98% confidence level) meets criteria for a coding sequence. The 295-residue amino acid translation product had a molecular weight of 31,974, in good agreement with the value determined experimentally by gel electrophoresis. The amino acid sequence, which was quite hydrophobic, was subjected to a theoretical analysis designed to predict membrane-spanning alpha-helical segments of integral membrane proteins; four such hydrophobic helices were predicted by this treatment. Additional amphipathic helices may also be present. A remarkable feature of the sequence is the existence of two segments of high uncompensated charge density, one positive and the other negative. Possible organization of the protein in the membrane is discussed. Asymmetry in the amino acid composition of translated DNA sequences was used to distinguish between two possible initiation codons. The use of this method as a criterion for authentication of coding regions is described briefly in an Appendix.

    Title The Hydrogen Ion-pumping Adenosine Triphosphatase of Platelet Dense Granule Membrane. Differences from F1f0- and Phosphoenzyme-type Atpases.
    Date September 1984
    Journal The Journal of Biological Chemistry
    Excerpt

    Using a coupled transport assay which detects only those ATPase molecules functionally inserted into the platelet dense granule membrane, we have characterized the inhibitor sensitivity, substrate specificity, and divalent cation requirements of the granule H+ pump. Under identical assay conditions, the granule ATPase was insensitive to concentrations of NaN3, oligomycin, and efrapeptin which almost completely inhibit ATP hydrolysis by mitochondrial membranes. The granule ATPase was inhibited by dicyclohexylcarbodiimide but only at concentrations much higher than those needed to maximally inhibit mitochondrial ATPase. Vanadate (VO3-) ion and ouabain also failed to inhibit granule ATPase activity at concentrations which maximally inhibited purified Na+,K+-ATPase. Two alkylating agents, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole and N-ethylmaleimide both completely inhibited H+ pumping by the granule ATPase under conditions where ATP hydrolysis by mitochondrial membranes or Na+,K+-ATPase was hardly affected. These results suggest that the H+-pumping ATPase of platelet granule membrane may belong to a class of ion-translocating ATPases distinct from both the phosphoenzyme-type ATPases present in plasma membrane and the F1F0-ATPases of energy-transducing membranes.

    Title Hydrogen Ion Cotransport by the Renal Brush Border Glutamate Transporter.
    Date February 1984
    Journal Biochemistry
    Excerpt

    Sodium ion dependent glutamate transport into rabbit renal brush border membrane vesicles is stimulated by low external pH and inhibited by low internal pH. Imposition of a pH difference (delta pH) (interior alkaline) across the vesicle membrane drives glutamate accumulation in the absence of other driving forces. This process requires Na+ but is not due to generation of an Na+ gradient in response to delta pH. Internal K+ stimulates both the rate and extent of glutamate accumulation, although K+ is not absolutely required for transport. Internal H+ inhibits the rate of glutamate accumulation by decreasing this K+ stimulation. Conversely, external K+ inhibits glutamate influx, and this inhibition can be overcome by lowering the external pH. These results indicate that H+ is cotransported with glutamate and suggest the possibility that, in the absence of internal K+, H+ can also fulfill the requirement for a countertransported ion.

    Title Acidification of Macrophage and Fibroblast Endocytic Vesicles in Vitro.
    Date July 1983
    Journal Proceedings of the National Academy of Sciences of the United States of America
    Excerpt

    We have used the pH-dependent fluorochrome fluorescein-dextran (FD) to study the acidification of prelysosomal vacuoles (endosomes) and lysosomes isolated from cultured macrophages and fibroblasts. FD was internalized by pinocytosis under conditions that allowed its selective localization in endosomes (1- to 5-min pulse) or in lysosomes (5-min pulse, 30-min chase). Fibroblasts were also exposed to FD at 20 degrees C, at which temperature endosome-lysosome fusion is inhibited. Cells were homogenized and labeled organelles were separated by centrifugation in Percoll density gradients. The addition of ATP rapidly decreased the internal pH of both endosomes and lysosomes, as indicated by a decrease in fluorescence intensity. The pH gradient was dissipated by H+ ionophores and ammonium chloride. Acidification was not affected by inhibitors of the mitochondrial F1, F0-ATPase or the Na+, K, K+-ATPase and did not require permeant anions, Na+, or K+. Of the inhibitors tested, only N-ethylmaleimide prevented the ATP-dependent acidification of both compartments. These findings provide direct support for the existence of an acidic prelysosomal compartment that may be acidified via the same type of H+ pump believed to operate in lysosomes and secretory granules.

    Title Flaaii (motc, Chev) of Salmonella Typhimurium is a Structural Gene Involved in Energization and Switching of the Flagellar Motor.
    Date May 1983
    Journal Journal of Bacteriology
    Excerpt

    The flaAII gene of Salmonella typhimurium has also been termed motC and cheV, because defective alleles may give rise to a nonflagellate, paralyzed, or nonchemotactic phenotype. We isolated a temperature-sensitive motility mutant (MY1) and have found that the mutation occurs in the flaAII gene. In temperature-jump experiments, MY1 could be converted from highly motile to paralyzed within 0.5 s, demonstrating that flaAII is a structural gene whose product is immediately essential for motor rotation. The mutant, although chemotactic at permissive temperatures (less than 36 degrees C), had a higher clockwise rotational bias than did the wild type; it can therefore be regarded simultaneously as motC(Ts) and cheV (tumbly). The only previously reported S. typhimurium cheV mutant was smooth-swimming. A shift toward counterclockwise bias accompanied loss of rotational speed in the restrictive temperature range. This result, by analogy with known proton motive force effects on motor switching, further indicates a central role of the flaAII (motC, cheV) protein in the energy transduction and switching process. Since there is no evidence associating it with the isolable entity known as the basal body, it may reside at the cytoplasmic face of the flagellar motor.

    Title Role of Registered Nurses in Error Prevention, Discovery and Correction.
    Date
    Journal Quality & Safety in Health Care
    Excerpt

    BACKGROUND: Registered nurses have a vital role in discovering and correcting medical error. OBJECTIVE: To describe the type and frequency of errors detected by American critical care nurses, and to ascertain who made the errors discovered by study participants. METHODS: Daily logbooks were used to collect information about errors discovered by a random sample of 502 critical care nurses during a 28-day period. RESULTS: Although the majority of errors discovered and corrected by critical care nurses involved medications (163/367), procedural errors were common (n = 115). Charting and transcription errors were less frequently discovered. The errors discovered by participants were attributed to a wide variety of staff members including nurses, doctors, pharmacists, technicians and unit secretaries. CONCLUSIONS: Given the importance of nurses in maintaining patient safety, future studies should identify factors that enhance their effectiveness to prevent, intercept and correct healthcare errors.

    Title Refinement in the Management of the Denervated Canine Urinary Bladder Using an Abdominal Vesicostomy.
    Date
    Journal Ilar Journal / National Research Council, Institute of Laboratory Animal Resources
    Excerpt

    Treatment of the neurogenic bladder in canine models of spinal cord injury presents challenges in ensuring bladder drainage. While vesicostomy is routine for humans, the procedure is not common in canines. Our study of bladder reinnervation involved transection of the nerve roots that mediate bladder contraction in 34 canines. An abdominal vesicostomy was created by fixing the everted mucosa to the skin incision. After euthanasia, we assessed the contractility of in vitro bladder muscle strips in response to muscarinic receptor stimulation. There were a total of 11 complications in 9 of the 34 animals. In two animals, the vesicostomy narrowed such that it could not be catheterized and in two other animals the vesicostomy closed to between 5 and 10 mm diameter. Another animal removed the stitches prior to complete healing, requiring further surgical procedures. In fi ve animals, partial prolapse of the bladder through the vesicostomy required surgical repair, and in one animal the bladder became infected and required antibiotic treatment. In the few animals in which irritation resulted from the constant contact of urine with the skin, daily topical application of petrolatum ointment alleviated this symptom. Gross inspection of the bladder at euthanasia and in vitro contractility of bladder muscle strips from these animals revealed no evidence of changes associated with bladder hypertrophy. This study demonstrated that permanent cutaneous vesicostomy is an optimal refinement method for management of the neurogenic bladder in canines. The procedure avoids the distress as well as potential bladder hypertrophy induced by multiple daily interventions to empty the bladder by either catheterization or manual compression.


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