Replication and Injury Associated With SARS-CoV-2 in Cultured Hepatocytes

Background

Liver dysfunction is one of the hallmarks of SARS-CoV-2 infection. The mechanism(s) of hepatic injury in SARS-CoV-2 infection remains controversial with some reporting viral replication and cellular injury and others suggesting lack of replication and injury due to non-cytopathogenic etiologies. To investigate this further, we evaluated SARS-CoV-2 replication in immortalized hepatic cell lines and primary hepatocytes, examined whether cell injury was associated with apoptotic pathways, and also determined the effect of the antiviral remdesivir on these processes.

Methods

Immortalized hepatocyte cell lines (HepG2 and Huh7.5), as well as primary human hepatocytes, were exposed to SARS-CoV-2 at a multiplicity of infection of 0.1 PFU/mL. Viral replication was evaluated by plaque assays, immunohistochemical staining for the viral spike protein, and caspase-3 expression evaluated with and without exposure to remdesivir.

Results

All hepatocyte cell lines and primary hepatocytes supported active replication of SARS-CoV-2. Significant cytopathic effect was observed by light microscopy, and caspase-3 staining supported activation of apoptotic pathways. Remdesivir abrogated infection in a dose-dependent fashion and was not independently associated with hepatocyte injury.

Conclusion

Hepatocytes appear to be highly permissive of SARS-CoV-2 replication which leads to rapid cell death associated with activation of apoptotic pathways. Viral replication and hepatocytes injury are abrogated with remdesivir. We conclude that active viral replication is most likely a key contributor to liver enzyme abnormalities observed in the setting of acute SARS-CoV-2 infection.

0268 Development of an Integrated Model of Sleep Deprivation in Adolescence

Introduction

Sleep deprivation is a consistently and widely concerning problem among adolescents. Although a few models have been proposed to explain the relationships and pathways through which factors influence sleep in adolescents, there are lack of theoretical models that apply both biological and behavioral factors that contribute to sleep deprivation across the trajectory of adolescent development. The current study proposes an integrated model that draws upon constructs from several influential theories with an aim to re-conceptualize factors associated with sleep deprivation as a chronic and cyclic problem that emerges from biological and behavioral changes in youth.

Methods

The Two Process Model of Sleep Regulation, Spielman’s 3p model, the theory of planned behavior, dual systems model, and sleep health framework are used to develop an integrated model of factors that lead to sleep deprivation in adolescents.

Results

The resulting integrated model highlights the importance of adolescent’s inherent nature of delayed sleep phase at pubertal onset (two process model); increased reward-seeking that precedes the structural maturation of their cognitive control and emotions (dual systems model); and their attitudes/perceptions towards sleep (theory of planned behavior), which is often geared toward not prioritizing sleep. Sleep health framework adequately frames the pattern of sleep-wakefulness in adolescents using a multidimensional approach of sleep. Moreover, the new model presents contextual factors (Spielman’s 3p model) and the way that these constructs interact in order to maintain a vicious cycle of insufficient sleep which leads to chronic sleep deprivation.

Conclusion

The current model portrays a wide-ranging view of mechanisms underlying sleep deprivation among adolescence by integrating both biological and behavioral aspects. The model is proposed to encourage researchers to explore these conceptual elements of biological and neurobiological changes, and behavioral problems in order to operationalize relevant measures to relate the concepts to sleep deprivation and subsequent health outcomes in adolescents.

Support

None

Zika virus replication and cytopathic effects in liver cells

Zika virus (ZIKV) has emerged globally as an important pathogen, since it has been recognized as a cause of microcephaly and other neurologic processes and sequalae in newborns. The virus shares homology with Hepaciviruses and therefore may be a cause of hepatitis. We sought to characterize ZIKV replication in hepatocyte-derived cell lines. Huh7.5 and HepG2 cells were infected with ZIKV and replication potential was evaluated by multiple methods including plaque assay, qRT-PCR, negative-strand ZIKV RNA production, and ZIKV NS1 protein production. Growth curves in cells and supernatant were compared to replicative capacity in Vero cells. Overall, viral replication in both hepatocyte lines approximated that observed in the Vero cells. Cell cytopathology was observed after 3 days of infection and apoptosis markers increased. Transmission electron microscopy revealed evidence of viral capsids in cells and negative staining revealed ZIKV particles in the supernatant. Conclusions: Hepatocyte-derived cell lines are permissive for ZIKV replication and produce an overt cytopathic effect consistent with development of an acute viral hepatitis. Further evaluation of replication and injury is warranted.

Dermal patch graft correction of severe chordee secondary to penile corporal body disproportion without urethral division in boys without hypospadias

Historically, significant ventral penile curvature secondary to corporal body disproportion has been corrected either by dorsal plication or division of the urethral plate. In the rare situations where there is severe chordee in the face of an intact urethra with an orthotopic meatus, division of the urethral plate is commonly performed at the time of grafting the ventral defect created by incising the tunica albuginea. Subsequently, a staged procedure is necessary to reconnect the urethra at a later date. Herein the authors present a novel technique that shows it is possible to perform successful dermal patch orthoplasty without division of the urethra in patients with a normal orthotopic meatus and urethra via urethral mobilization. Three patients over the past 3 years with severe ventral chordee, orthotopic meati and normal urethral anatomy presented for correction. Two patients were 18 years old and one was 10 years old. All three boys were circumcised. The two older boys insisted on dorsal plication as a first approach which worked only temporarily for about 6 months while the younger boy had no prior surgery performed. Each boy underwent a circumcising incision, degloving of the shaft skin, extensive urethral mobilization and dermal patch graft orthoplasty to correct chordee. All surgeries were performed in an outpatient setting. No urinary drainage was used in any patient and a simple bio-occlusive dressing was employed in each case. Follow-up ranged from 11 months to 2 years (mean 1.5 years). All three boys have strong straight erections, full well directed urinary streams and no complications noted to date. Our conclusion based on this experience is that extensive urethral mobilization can allow for correction of severe ventral chordee without urethral division in a single operative setting in boys without hypospadias and a normal urethra. The accompanying movie herein describes the surgical technique.

Construction and characterization of stable, constitutively expressed, chromosomal green and red fluorescent transcriptional fusions in the select agents, Bacillus anthracis, Yersinia pestis, Burkholderia mallei, and Burkholderia pseudomallei

Here, we constructed stable, chromosomal, constitutively expressed, green and red fluorescent protein (GFP and RFP) as reporters in the select agents, Bacillus anthracis, Yersinia pestis, Burkholderia mallei, and Burkholderia pseudomallei. Using bioinformatic approaches and other experimental analyses, we identified P0253 and P1 as potent promoters that drive the optimal expression of fluorescent reporters in single copy in B. anthracis and Burkholderia spp. as well as their surrogate strains, respectively. In comparison, Y. pestis and its surrogate strain need two chromosomal copies of cysZK promoter (P2cysZK) for optimal fluorescence. The P0253-, P2cysZK-, and P1-driven GFP and RFP fusions were first cloned into the vectors pRP1028, pUC18R6KT-mini-Tn7T-Km, pmini-Tn7-gat, or their derivatives. The resultant constructs were delivered into the respective surrogates and subsequently into the select agent strains. The chromosomal GFP- and RFP-tagged strains exhibited bright fluorescence at an exposure time of less than 200 msec and displayed the same virulence traits as their wild-type parental strains. The utility of the tagged strains was proven by the macrophage infection assays and lactate dehydrogenase release analysis. Such strains will be extremely useful in high-throughput screens for novel compounds that could either kill these organisms, or interfere with critical virulence processes in these important bioweapon agents and during infection of alveolar macrophages.

Role of registered nurses in error prevention, discovery and correction

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.

Development and evaluation of a genetics literacy assessment instrument for undergraduates

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.

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

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.

Synaptotagmin I-DeltaC2B. A novel synaptotagmin isoform with a single C2 domain in the bovine adrenal medulla

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.

AnkB, a periplasmic ankyrin-like protein in Pseudomonas aeruginosa, is required for optimal catalase B (KatB) activity and resistance to hydrogen peroxide

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.

La Vega slit procedure for the treatment of phimosis

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.

Chordee repair utilizing a novel technique ensuring neurovascular bundle preservation

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.

Medical management of phimosis in children: our experience with topical steroids

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.

Medical management of phimosis in children: our experience with topical steroids

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.

A PC12 variant lacking regulated secretory organelles: aberrant protein targeting and evidence for a factor inhibiting neuroendocrine gene expression

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.

Regulation of the macrophage vacuolar ATPase and phagosome-lysosome fusion by Histoplasma capsulatum

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.

Regulation of the Macrophage Vacuolar ATPase and Phagosome-Lysosome Fusion by Histoplasma capsulatum

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 (Mø) lysosomal hydrolases. To determine the mechanism of pH regulation, we evaluated the function of the vacuolar ATPase (V-ATPase) in RAW264.7 Mø infected with Hc yeast or the nonpathogenic yeast Saccharomyces cerevisae (Sc). Incubation of Hc-infected Mø 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 Mø phagosomes.

Quantification of axonal damage in traumatic brain injury: affinity purification and characterization of cerebrospinal fluid tau proteins

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.

Disposable bedpads for incontinence: predicting their clinical leakage properties using laboratory tests

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.

Predicting the leakage performance of small bodyworn disposable incontinence pads using laboratory tests

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.

Active and passive compliance of the fetal bovine bladder

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.

Active specific immunotherapy of metastatic melanoma with an antiidiotype vaccine: a phase I/II trial of I-Mel-2 plus SAF-m

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.

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

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.

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

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.

Identification of microtubule-associated protein tau isoforms in Alzheimer's paired helical filaments

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.

Monoclonal antibody PHF-9 recognizes phosphorylated serine 404 of tau protein and labels paired helical filaments

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.

Resorption-cycle-dependent polarization of mRNAs for different subunits of V-ATPase in bone-resorbing osteoclasts

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.

An institutional commitment to pain management

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.

Cloning and functional characterization through antisense mapping of a kappa 3-related opioid receptor

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.

Fatigue in patients with cancer receiving interferon alpha

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.

Phase II study of low dose cyclophosphamide and intravenous interleukin-2 in metastatic renal cancer

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.

Preliminary results of laser tissue welding in extravesical reimplantation of the ureters

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.

Cloning and functional expression of a tetrabenazine sensitive vesicular monoamine transporter from bovine chromaffin granules

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].

Alzheimer's paired helical filaments: amyloid precursor protein epitope mapping

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.

Cloning and sequence analysis of an H(+)-ATPase-encoding gene from the human dimorphic pathogen Histoplasma capsulatum

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.

Saccharomyces cerevisiae expression of exogenous vacuolar ATPase subunits B

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.

Peptide splicing in the vacuolar ATPase subunit A from Candida tropicalis

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.

Vaginal replacement in children

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.

Structure and expression of subunit A from the bovine chromaffin cell vacuolar ATPase

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.

Complications of urinary tract reconstruction

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.