Comparison of mechanical and electrical activity and interstitial cells of Cajal in urinary bladders from wild-type and W/Wv mice

Background and purpose:

W/W^v and wild-type murine bladders were studied to determine whether the W/W^v phenotype, which causes a reduction in, but not abolition of, tyrosine kinase activity, is a useful tool to study the function of bladder interstitial cells of Cajal (ICC).

Experimental approach:

Immunohistochemistry, tension recordings and microelectrode recordings of membrane potential were performed on wild-type and mutant bladders.

Key results:

Wild-type and W/W^v detrusors contained c-Kit- and vimentin-immunopositive cells in comparable quantities, distribution and morphology. Electrical field stimulation evoked tetrodotoxin-sensitive contractions in wild-type and W/W^v detrusor strips. Atropine reduced wild-type responses by 50% whereas a 25% reduction occurred in W/W^v strips. The atropine-insensitive component was blocked by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both tissue types. Wild-type and W/W^v detrusors had similar resting membrane potentials of −48 mV. Spontaneous electrical activity in both tissue types comprised action potentials and unitary potentials. Action potentials were nifedipine-sensitive whereas unitary potentials were not. Excitatory junction potentials were evoked by single pulses in both tissues. These were reduced by atropine in wild-type tissues but not in W/W^v preparations. The atropine-insensitive component was abolished by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both preparations.

Conclusions and implications:

Bladders from W/W^v mice contain c-Kit- and vimentin-immunopositive ICC. There are similarities in the electrical and contractile properties of W/W^v and wild-type detrusors. However, significant differences were found in the pharmacology of the responses to neurogenic stimulation with an apparent up-regulation of the purinergic component. These findings indicate that the W/W^v strain may not be the best model to study ICC function in the bladder.     

A profile of the online dissemination of national influenza surveillance data

Background  

Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.     

Association of seborrhoeic warts with skin cancer in renal transplant recipients**

Background Renal transplant recipients (RTR) have a well recognized increased risk of cutaneous malignancy. A clinical observation that RTR with skin cancer often had multiple seborrhoeic warts prompted an investigation in RTR into the relationship between seborrhoeic warts and skin cancer and an exploration into potential risk factors for seborrhoeic warts in this population, including infection with human papillomavirus (HPV). Methods This was a case control study involving 308 RTR. Clinical examinations identified seborrhoeic warts. Histological records reviewed to look for evidence of prior cutaneous malignancy. Seroprevalence of antibodies to 34 different HPV types tested using multiplex serology. Odds ratios (OR) calculated using unconditional logistic regression analysis to look for associations between skin cancer, HPV infection and seborrhoeic warts, controlling for potential confounding factors of gender, age and time since transplantation. Results Seborrhoeic warts were associated with non‐melanoma skin cancer [OR = 3.7; 95% confidence intervals (CI) ranging from 1.6–8.9; P = 0.002] when confounding factors of gender, age and time since transplantation were controlled for. There was also an association between seborrhoeic warts and viral warts (OR = 3.0, CI: 1.6–5.4; P < 0.0001), but no association between seborrhoeic warts and infection with single or multiple HPV types. Conclusions Seborrhoeic warts are associated with cutaneous malignancy, but not with any of the HPV types tested. The reasons for this association are unclear. RTR with multiple seborrhoeic warts may require more regular cutaneous examination to monitor for early signs of skin cancer.     

Surgical treatment of obesity

Obesity is very prevalent. Most treatments fail owing to hard-wired survival mechanisms, linking stress and appetite, which have become grossly maladaptive in the industrial era. Antiobesity (bariatric) surgery is a seemingly drastic, efficacious therapy for this serious disease of energy surfeit. Technical progress during the last two decades has greatly improved its safety. The surgical principles of gastric restriction and/or gastrointestinal diversion have remained largely unchanged over 40 years, although mechanisms of action have been elucidated concomitant with advances in knowledge of the molecular biology of energy balance and appetite regulation. Results of bariatric surgery in large case-series followed for at least 10 years consistently demonstrate amelioration of components of the insulin-resistance metabolic syndrome and other comorbidities, significantly improving quality of life. Furthermore, bariatric surgery has convincingly been demonstrated to reduce mortality compared with nonoperative methods. This surgery requires substantial preoperative and postoperative evaluation, teaching, and monitoring to optimize outcomes. In the absence of effective societal changes to restore a healthy energy balance, bariatric surgery is an important tool for treating a very serious disease.     

The effect of syringe exchange use on high-risk injection drug users: a cohort study

OBJECTIVE: To determine whether syringe exchange program use is associated with cessation of syringe sharing among high-risk injection drug users. DESIGN AND METHODS: Between 1992 and 1996, street-recruited injection drug users were interviewed and received HIV testing and counseling semi-annually, as part of a dynamic cohort study. We examined a cohort of 340 high-risk injection drug users for whom two observations, 6-months apart, were available and who reported syringe sharing at the first interview. Multivariate logistic regression analysis was performed to determine the relationship between syringe exchange program use and cessation of syringe sharing, while controlling for confounding factors. RESULTS: At follow-up interview, 60% (204 of 340) reported quitting syringe sharing. High-risk injection drug users who began using the syringe exchange program were more likely to quit sharing syringes [adjusted odds ratio (AOR), 2.68; 95% confidence interval (CI), 1.35-5.33], as were those who continued using the syringe exchange program (AOR,1.98; 95% CI, 1.05-3.75) in comparison with non-syringe exchange program users, while controlling for confounding factors. CONCLUSIONS: The initiation and continuation of syringe exchange program use among high-risk injection drug users is independently associated with cessation of syringe sharing. Syringe exchange program use can be an important component in reducing the spread of blood-borne infectious diseases among high-risk injection drug users.     

糖基化恢复冷藏血小板的存活率

血小板冷藏会使血管假性血友病因子受体复合物(von Willebrand factor receptor complex)聚集成簇。巨噬细胞αMβ2 整合素结合在成簇复合物的GPIbα亚基,导致输注的冷藏血小板被快速清除。因此输注用血小板不能冷藏,但现在的室温保存方式也存在很大缺点。我们已证明αMβ2是一种凝集素,它能识别GPIbα的N-连接葡聚糖上暴露的β-N-乙酰葡萄胺。冷藏血小板的酶促半乳糖苷化阻止了αMβ2的这种识别,延长了有