Novel ITGB4 mutations in lethal and nonlethal variants of epidermolysis bullosa with pyloric atresia: missense versus nonsense

Epidermolysis bullosa with pyloric atresia (EB-PA), an autosomal recessive genodermatosis, manifests with neonatal cutaneous blistering associated with congenital pyloric atresia. The disease is frequently lethal, but nonlethal cases have also been reported. Expression of the alpha6 beta4 integrin is altered at the dermal-epidermal basement-membrane zone; recently, mutations in the corresponding genes (ITGA6 and ITGB4) have been disclosed in a limited number of patients, premature termination codons in both alleles being characteristic of lethal variants. In this study, we have examined the molecular basis of EB-PA in five families, two of them with lethal and three of them with nonlethal variants of the disease. Mutation analysis disclosed novel lesions in both ITGB4 alleles of each proband. One of the patients with lethal EB-PA was a compound heterozygote for premature termination-codon mutations (C738X/4791delCA), whereas the other patient with a lethal variant was homozygous for a missense mutation involving a cysteine residue (C61Y). The three nonlethal cases had missense mutations in both alleles (C562R/C562R, R1281W/R252C, and R1281W/R1281W). Immunofluorescence staining of skin in two of the nonlethal patients and in one of the lethal cases was positive, yet attenuated, for alpha6 and beta4 integrins. These results confirm that ITGB4 mutations underlie EB-PA and show that missense mutations may lead to nonlethal phenotypes.

A phase I trial of vinorelbine in combination with mitoxantrone in patients with refractory solid tumors

Vinorelbine (Navelbine) is a unique semi-synthetic vinca-alkaloid with a favorable safety profile that has demonstrated significant antitumor activity in patients with non-small cell lung cancer, advanced breast cancer, advanced ovarian cancer and Hodgkin's disease. The most common dose-limiting toxicity is neutropenia, while other reported toxicities are minimal. Mitoxantrone (Novantrone) is an anthracene derivative that has demonstrated antitumor activity in patients with breast cancer, ovarian cancer, acute leukemia, and lymphoma. Mitoxantrone also has a very favorable toxicity profile with significantly less nausea and vomiting, alopecia, and stomatitis as compared with anthracyclines. The dose-limiting toxicity for mitoxantrone is leukopenia. The study was designed to determine the safety and maximally tolerated dose of IV vinorelbine used in combination with a fixed dose of mitoxantrone for the treatment of patients with refractory solid tumors. Vinorelbine was administered on days 1 and 8 of the treatment regimen as a short IV infusion. The starting dose was 15 mg/m2. Mitoxantrone was administered as a 20-min infusion on day 1 only at a fixed dose of 10 mg/m2. Seventeen patients with solid malignancies were entered in the study. For personal reasons, one patient decided to discontinue the treatment after day 1 of cycle 1. Therefore, 16 patients were evaluable for toxicity. The main toxicity was myelosuppression which was dose-limiting and resulted in dose reductions and delays. The use of G-CSF had a minimal overall impact on this regimen. Stable disease was observed in three cases. In patients previously treated with chemotherapy, the maximally tolerated dose was defined as vinorelbine 20 mg/m2 on days 1 and 8 and mitoxantrone 10 mg/m2 on day 1 without growth factor support. These doses can be recommended for phase II study of the regimen as salvage treatment.

Impact of the Libby Zion case on graduate medical education in internal medicine

Residency training in New York State was substantially altered by the Libby Zion case. Work-hour limitations and augmented supervisory requirements changed the patterns of training--particularly in internal medicine--but with uncertain impacts on the quality of education and patient care. In this historical analysis, we review another major effect of the case: a substantial augmentation of the number of trainees. The need to maintain adequate inpatient staffing--within the ground rules of the Residency Review Committee, and in consideration of the reimbursement formulae and financial climate of New York State--conspired to promote substantial residency program expansion. Similar forces contributed to a national trend to increase the number of trainees. The history, cost and impact of these personnel changes are reviewed.

Typing of dengue viruses in clinical specimens and mosquitoes by single-tube multiplex reverse transcriptase PCR

In recent years, dengue viruses (serotypes 1 to 4) have spread throughout tropical regions worldwide. In many places, multiple dengue virus serotypes are circulating concurrently, which may increase the risk for the more severe form of the disease, dengue hemorrhagic fever. For the control and prevention of dengue fever, it is important to rapidly detect and type the virus in clinical samples and mosquitoes. Assays based on reverse transcriptase (RT) PCR (RT-PCR) amplification of dengue viral RNA can offer a rapid, sensitive, and specific approach to the typing of dengue viruses. We have reduced a two-step nested RT-PCR protocol to a single-tube reaction with sensitivity equivalent to that of the two-step protocol (1 to 50 PFU) in order to maximize simplicity and minimize the risk of sample cross-contamination. This assay was also optimized for use with a thermostable RT-polymerase. We designed a plasmid-based internal control that produces a uniquely sized product and can be used to control for both reverse transcription or amplification steps without the risk of generating false-positive results. This single-tube RT-PCR procedure was used to type dengue viruses during the 1995 and 1997-1998 outbreaks in Nicaragua. In addition, an extraction procedure that permits the sensitive detection of viral RNA in pools of up to 50 mosquitoes without PCR inhibition or RNA degradation was developed. This assay should serve as a practical tool for use in countries where dengue fever is endemic, in conjunction with classical methods for surveillance and epidemiology of dengue viruses.

Enhanced phenotypic expression of alpha-1-antitrypsin deficiency in an MZ heterozygote with chronic hepatitis C

A middle-aged white man of Scotch-Irish ancestry, being treated for chronic hepatitis C, was found to be heterozygous for alpha1-antitrypsin deficiency (PiMZ phenotype) after diagnostic PAS-positive, diastase-resistant globules were detected in a liver biopsy. The globules had not been present in a biopsy obtained 4 yr previously. He was also found to be heterozygous for the cys282tyr mutation of the HFE gene, which is the chief cause of HLA-linked hereditary hemochromatosis (HHC). His liver disease progressed over 4 yr from mild hepatitis to moderate hepatitis with cirrhosis despite therapy with interferon-alpha, and phlebotomy plus interferon. These conditions appeared to have synergistic effects, with the chronic viral hepatitis unmasking the alpha1AT deficiency, and the alpha1AT deficiency (and possibly the heterozygosity for HHC), exacerbating the course of the hepatitis C.

Expression and function of recombinant endothelial nitric oxide synthase gene in canine basilar artery after experimental subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Gene transfer with recombinant viral vectors encoding vasodilator proteins may be useful in therapy of cerebral vasospasm after subarachnoid hemorrhage (SAH). Relaxations mediated by nitric oxide are impaired in cerebral arteries affected by SAH. The present study was designed to determine the effect of SAH on the efficiency of ex vivo adenovirus-mediated gene transfer to canine basilar arteries and to examine whether expression of recombinant endothelial nitric oxide synthase (eNOS) gene may have functional effects on vasomotor reactivity of spastic arteries affected by SAH.

METHODS

Replication-deficient recombinant adenovirus vectors encoding bovine eNOS (AdCMVeNOS) and Escherichia coli beta-galactosidase (AdCMVbeta-Gal) genes were used for ex vivo gene transfer. Rings of basilar arteries obtained from control dogs and dogs exposed to SAH were incubated with the vectors in minimum essential medium. Twenty-four hours after gene transfer, expression and function of the recombinant genes were evaluated by (1) histochemical or immunohistochemical staining, (2) beta-galactosidase protein measurement, and (3) isometric tension recording.

RESULTS

Transduction with AdCMVbeta-Gal and AdCMVeNOS resulted in the expression of recombinant beta-galactosidase and eNOS proteins mostly in the vascular adventitia. The expression of beta-galactosidase protein was approximately 2-fold higher in SAH arteries than in normal arteries. Endothelium-dependent relaxations caused by bradykinin and substance P were suppressed in SAH arteries. The relaxations to bradykinin were significantly augmented in both normal and SAH arteries after AdCMVeNOS transduction but not after AdCMVbeta-Gal transduction. The relaxations to substance P were augmented by AdCMVeNOS transduction only in normal arteries. Bradykinin and substance P caused relaxations even in endothelium-denuded arteries, when the vessels were transduced with AdCMVeNOS. These endothelium-independent (adventitia-dependent) relaxations to bradykinin observed after AdCMVeNOS transduction were similar between normal and SAH arteries, whereas those to substance P were significantly reduced in SAH arteries compared with normal arteries.

CONCLUSIONS

These results suggest that expression of recombinant proteins after adenovirus-mediated gene transfer may be enhanced in cerebral arteries affected by SAH and that successful eNOS gene transfer to spastic arteries can at least partly restore the impaired nitric oxide-mediated relaxations through local (adventitial) production of nitric oxide.

Phase I and pharmacokinetic study of paclitaxel in combination with biricodar, a novel agent that reverses multidrug resistance conferred by overexpression of both MDR1 and MRP

PURPOSE

To evaluate the feasibility of administering biricodar (VX-710; Incel, Vertex Pharmaceuticals Inc, Cambridge, MA), an agent that modulates multidrug resistance (MDR) conferred by overexpression of both the multidrug resistance gene product (MDR1) P-glycoprotein and the MDR-associated protein (MRP) in vitro, in combination with paclitaxel. The study also sought to determine the maximum-tolerated dose (MTD) of paclitaxel that could be administered with biologically relevant concentrations of VX-710 and characterize the toxicologic and pharmacologic profiles of the VX-710/ paclitaxel regimen.

PATIENTS AND METHODS

Patients with solid malignancies were initially treated with VX-710 as a 24-hour infusion at doses that ranged from 10 to 120 mg/m2 per hour. After a 2-day washout period, patients were re-treated with VX-710 on an identical dose schedule followed 8 hours later by paclitaxel as a 3-hour infusion at doses that ranged from 20 to 80 mg/m2. The pharmacokinetics of both VX-710 and paclitaxel were studied during treatment with VX-710 alone and VX-710 and paclitaxel. Thereafter, patients received VX-710 and paclitaxel every 3 weeks.

RESULTS

VX-710 alone produced minimal toxicity. The toxicologic profile of the VX-710/paclitaxel regimen was similar to that reported with paclitaxel alone; neutropenia that was noncumulative was the principal dose-limiting toxicity (DLT). The MTD levels of VX-710/ paclitaxel were 120 mg/m2 per hour and 60 mg/m2, respectively, in heavily pretreated patients and 120/60 to 80 mg/m2 per hour in less heavily pretreated patients. At these dose levels, VX-710 steady-state plasma concentrations (Css) ranged from 2.68 to 4.89 microg/mL, which exceeded optimal VX-710 concentrations required for MDR reversal in vitro. The pharmacokinetics of VX-710 were dose independent and not influenced by paclitaxel. In contrast, VX-710 reduced paclitaxel clearance. At the two highest dose levels, which consisted of VX-710 120 mg/m2 per hour and paclitaxel 60 and 80 mg/m2, pertinent pharacokinetic determinants of paclitaxel effect were similar to those achieved with paclitaxel as a 3-hour infusion at doses of 135 and 175 mg/m2, respectively.

CONCLUSION

VX-710 alone is associated with minimal toxicity. In combination with paclitaxel, biologically relevant VX-710 plasma concentrations are achieved and sustained for 24 hours, which simulates optimal pharmacologic conditions required for MDR reversal in vitro. The acceptable toxicity profile of the VX-710/ paclitaxel combination and the demonstration that optimal pharmacologic conditions for MDR reversal are achievable support a rationale for further trials of VX710/paclitaxel in patients with malignancies that are associated with de novo or acquired resistance to paclitaxel caused by overexpression of MDR1 and/or MRP.

Industrial shift systems

This technical report describes the identification of shift systems worked by industrial shiftworkers in England, Scotland and Wales. A diverse range of shift systems were reported to be in operation across 27 industrial sectors. Companies employed up to 14 different shift systems at a particular site. The numbers of shiftworkers on a given shift schedule ranged from 1 to 2977. Most systems employed fewer than 100 people. The majority of rotas were regular, rotating systems. The most common shift durations were 8 or 12 h. Compared to earlier surveys of shiftwork prevalence in certain industries there appeared to be a substantial increase over the past 3 decades in the proportion of the workforce who work shifts. Information about the average numbers of hours worked per week on major system types is given. In addition, data for the range of shifts per cycle, the distribution of shifts and distributions of their start and end times are presented.

Fluticasone propionate 750 micrograms/day versus beclomethasone dipropionate 1500 micrograms/day: comparison of efficacy and adrenal function in paediatric asthma

BACKGROUND

Previous studies have suggested a 2:1 efficacy advantage of fluticasone propionate (FP) over beclomethasone dipropionate (BDP) in adults on high dose inhaled steroids and children on low dose inhaled steroids. The lower doses of FP required to provide equivalent efficacy to BDP also appear to have fewer systemic effects as measured by adrenal function.

METHODS

The efficacy and safety of FP 750 micrograms/day and BDP 1500 micrograms/day were compared in 30 children with persistent asthma (requiring 1000-2000 micrograms/day of inhaled corticosteroids) in a 12 week randomised double blind crossover study. Medication was delivered by a spacer device in two divided doses. Primary efficacy variables were peak expiratory flows (PEF). Adrenal function was assessed by 24 hour urinary free cortisol levels at eight and 12 weeks and ACTH and low dose synacthen tests (LDST) at 12 weeks. The results were adjusted for sequence and period differences.

RESULTS

There was no difference in the primary efficacy variables over the two 12 week treatment periods (difference in adjusted means for morning PEF 1.3 l/min (95% CI -6.1 to 8.8), p = 0.112) and symptom scores (cough, tachypnoea, wheeze, shortness of breath; difference in adjusted means of night time scores: -0.06 (95% CI -0.14 to 0.03); p = 0.136). Similar degrees of mild adrenal dysfunction were found during BDP and FP treatment phases. Identical height gain velocities were shown during the corresponding periods.

CONCLUSIONS

FP 750 micrograms/day is as effective as BDP 1500 micrograms/day in children with persistent asthma. At these very high doses we were unable to demonstrate a safety advantage of FP over BDP as assessed by adrenal function. However, measures of adrenal function may have been influenced by concurrent and previous systemic steroid usage, and possibly by effects of disease activity.

Shared learning for community based maternity care

In order to ensure the best quality of maternity care midwives and doctors must work closely together but unfortunately the necessary interdisciplinary cooperation and respect has not always been present. This paper suggests that the benefits claimed for interprofessional education, which remain largely untested in maternity care, are being put forward as a panacea for earlier difficulties. It outlines some of the initiatives currently taking place. Material ripe for shared learning is identified and it is suggested that shared teaching in addition to shared learning for midwifery and medical students and for midwives and doctors should be the norm. Learners may then eventually provide shared care based on both their shared learning experiences and also on the role model of shared teaching. Such a major change would require considerable political will, including a shift in funding. There is some evidence that the necessary political will is developing and this may be given more emphasis by the need for teaching to follow care as the NHS becomes more primary-care led.

Operation Red Box: a pilot project of needle and syringe drop boxes for injection drug users in East Baltimore

We assessed the acceptability and the use of a community-based needle and syringe disposal project designed to serve injection drug users. In June 1996, three surplus U.S. mail collection boxes were painted red and used as syringe and needle drop boxes in locations with high drug use in East Baltimore. Acceptance of the drop boxes was measured by focus groups of residents, drug users, and police, held before and after project implementation. Use was measured by weekly counts of needles recovered from the red boxes. A sample of all deposited needles was randomly chosen for needle washing and subsequent HIV antibody testing. Community impact was measured by systematic surveys of needles discarded on public sidewalks, in areas with and areas without drop boxes. Before implementation, members of focus groups expressed concerns that drop boxes could convey mixed messages to youth (e.g., seeming to condone drug use), might result in increased loitering, and could further community stigmatization. After project implementation, all focus groups expressed support of project expansion. In the first 10 months, 2971 needles were collected. Of 156 needles tested, 10.9% were positive for HIV antibody. Needle counts on the street showed no significant change in red box areas compared with control areas. In this pilot project, red boxes were accepted by the community and drug users. Police officers also used the boxes to dispose of confiscated needles. Although limited in the number of drop boxes and follow-up time, this pilot project shows promise as a community-based method of safe needle disposal.

The impact of early and late shift changeovers on sleep, health, and well-being in 8- and 12-hour shift systems

The effects on industrial shift workers of the timing of the changeover from the night to morning shift and of the length of the shift were examined. Two groups changed over at 6 a.m. and worked either 8-hr or 12-hr shift systems; the other 2 groups changed over at 7 a.m., working either 8- or 12-hr systems. Night sleeps between consecutive shifts that started at 6 a.m. were shorter and more disrupted than those starting at 7 a.m. Day sleeps following night shifts that finished at 6 a.m. were longer and less disrupted than those finishing at 7 a.m. Early starts were associated with poorer psychological and physical health. These effects of changeover time are considered in relation to the circadian rhythms in sleep duration and propensity. Although several measures favored 12-hr shifts, physical health indicators appeared to favor 8-hr systems, especially in combination with late changeovers. However, the observed effects of shift length on chronic outcome measures are somewhat inconsistent with previous research findings.

Data for diagnosis, monitoring and treatment in indigenous health: the case of cervical cancer

Deficiencies in the availability and quality of data on the health status of indigenous Australians have long been recognised. For cervical cancer, data demonstrate a 2-5 fold greater incidence rate and an 8-10 fold greater mortality rate for Indigenous women compared to non-Indigenous Australians. However, incidence and mortality data are only available for some states and there is little or no information available on the geographic or social distribution of risk, or the reasons for risk differentials. There are also little or no data on the utilisation of, or preferences for, screening services. Thus, while there is clearly a need for a cervical cancer control program specifically to target Indigenous women, current data are inadequate to inform planning and implementation, and current systems are inadequate to monitor effectiveness. This situation is the result of insufficient research and inadequate attention to recording of Indigenous status in routine data systems and applies to a greater or lesser extent across the spectrum of health of Indigenous Australians. Health workers across the spectrum in mainstream and Indigenous medical services have a shared responsibility for improving the availability and quality of data and ensuring the appropriate use of information necessary to achieve and monitor improvements in service delivery and health status of Indigenous people.

Nursing assessment and intervention for adult hemodialysis patients: application of Roy's Adaptation Model

A comprehensive assessment tool and intervention typology for adult hemodialysis patients, based on the Roy Adaptation Model, is presented. The Roy model is reviewed, and examples from the assessment tool and intervention typology are presented. A case study illustrates application of the tool and typology to nephrology nursing. Comparison of the tool and typology with the ANNA Standards of Clinical Practice revealed that the Roy Adaptation Model includes additional important aspects of nephrology nursing practice.

Duplication of ATR inhibits MyoD, induces aneuploidy and eliminates radiation-induced G1 arrest

Chromosome 3q alterations occur frequently in many types of tumours. In a genetic screen for loci present in rhabdomyosarcomas, we identified an isochromosome 3q [i(3q)], which inhibits muscle differentiation when transferred into myoblasts. The i(3q) inhibits MyoD function, resulting in a non-differentiating phenotype. Furthermore, the i(3q) induces a 'cut' phenotype, abnormal centrosome amplification, aneuploidy and loss of G1 arrest following gamma-irradiation. Testing candidate genes within this region reveals that forced expression of ataxia-telangiectasia and rad3-related (ATR) results in a phenocopy of the i(3q). Thus, genetic alteration of ATR leads to loss of differentiation as well as cell-cycle abnormalities.

Predicting communicative competence at 2 and 3 years from pragmatic skills at 10 months

It is proposed that children play an important part in determining the kinds of linguistic experience they receive, influencing their language environment by means of early pragmatic communication. These early behaviours may also be predictive of later communicative competence. As a preliminary investigation into the wider implications of children's potential influence over their linguistic environment, a study was undertaken which looked at infant pragmatic signalling systems and joint engagement skills, to establish whether these early interactive behaviours might be related to children's subsequent communicative development. During the course of the study, the frequency and distribution of early pragmatic behaviours in a random sample of 145 10-month-old infants were investigated, and their subsequent language development followed up at ages 24 and 36 months. The study examined (a) the predictive validity of specific pragmatic behaviours at age 10 months for language development at age 24 months and (b) the specificity and stability of profiles of communicative disability at 2 and 3 years. A subset of behaviours was identified which would have correctly predicted 82.4% of children found to have communicative difficulties at 24 months and 85.4% of those who did not. Predictive language profiles drawn up at age 24 months were substantially confirmed when the children were reassessed at age 36 months. It is proposed that specific early communicative behaviours may be predictive of a child's subsequent linguistic development. Additionally, 2-year-old children will be exhibiting certain patterns of language acquisition which may be significant for subsequent linguistic development. Implications for intervention are discussed.