黄体生成素对小鼠子宫生长发育及其相关基因表达的影响

目的：通过分析黄体生成素(LH)受体基因敲除小鼠子宫生长发育相关基因表达的改变,探讨LH对子宫生长发育的影响。方法：应用基因芯片和RT-PCR方法分析LH受体基因敲除鼠子宫基因表达。结果：155个基因表达改变超过3倍;与生长发育相关的基因中,10个基因表达上调、5个基因表达下调;细胞周期蛋白cyclin D基因上调、cyclin B基因下调,半定量RT-PCR分析证实了细胞周期蛋白基因表达的变化,表明LH受体基因敲除鼠子宫细胞生长发生阻滞,21 d雌二醇和孕酮替代疗法不能够使这些基因表达的改变完全恢复正常。结论：LH除促进卵巢类固醇激素合成调控子宫生长发育外,还对子宫生长发育直接起作用。     

Photochemical inactivation of viruses and bacteria in platelet concentrates by use of a novel psoralen and long-wavelength ultraviolet light

BACKGROUND: A photochemical treatment process has been developed for the inactivation of viruses and bacteria in platelet concentrates. This process is based on the photochemical reaction of a novel psoralen, S- 59, with nucleic acids upon illumination with long-wavelength ultraviolet light (UVA, 320–400 nm). STUDY DESIGN AND METHODS: High levels of pathogens were added to single-donor platelet concentrates containing 3 to 5 × 10(11) platelets in 300 mL of 35-percent autologous plasma and 65-percent platelet additive solution. After treatment with S-59 (150 microM) and UVA (0-3 J/cm2), the infectivity of each pathogen was measured with established biologic assays. In vitro platelet function after photochemical treatment was evaluated during 7 days of storage by using a panel of 14 assays. The in vivo recovery and life span of photochemically treated platelets were evaluated after 24 hours of storage in a primate transfusion model. RESULTS: The following levels of pathogen inactivation were achieved:>10(6.7) plaque-forming units (PFU) per mL of cell-free human immunodeficiency virus (HIV),>10(6.6) PFU per mL of cell-associated HIV,>10(6.8) infectious dose (ID50) per mL of duck hepatitis B virus (a model for hepatitis B virus),>10(6.5) PFU per mL of bovine viral diarrhea virus (a model for hepatitis C virus),>10(6.6) colony-forming units of Staphylococcus epidermidis, and>10(5.6) colony-forming units of Klebsiella pneumoniae. Expression of integrated HIV was inhibited by 0.1 microM S- 59 and 1 J per cm2 of UVA. In vitro and in vivo platelet function were adequately maintained after antiviral and antibacterial treatment. CONCLUSION: Photochemical treatment of platelet concentrates offers the potential for reducing transfusion-related viral and bacterial diseases.     

Feasibility of laparoscopic tumour nephrectomy in children

Aims

The laparoscopic approach to tumour nephrectomy in children is controversial. We therefore reviewed our institution's cases of tumour nephrectomy (laparoscopic, open, and converted) to better understand which is suitable for this approach, what factors prevent it, and whether one can excise tumours greater than the CCLG recommendation of 300 ml.

The impact of route of delivery and presentation on twin neonatal and infant mortality: a population-based study in the USA, 1995–97

Objective: We examined whether the route of delivery for near-term (???34 weeks' gestation) twins, as candidates for vaginal delivery, affected neonatal and infant mortality rates. We further evaluated whether these mortality rates were modified by fetal presentation.

Methods: A population-based retrospective cohort study based on the matched multiple births data in the USA (1995–97) was performed. Analyses were restricted to non-malformed liveborn twins delivered at ??34 weeks' gestation. Twins with breech–breech and breech–vertex presentations were excluded, since they are not candidates for vaginal delivery. Neonatal mortality rates (death within the first 27 days) and post-neonatal mortality rates (death between 28 and 365 days) per 1000 twin live births, by route of delivery and fetal presentation, were derived. The associations between neonatal mortality, post-neonatal mortality and the route of delivery for vertex–breech versus vertex–vertex presentations were expressed based on relative risks (RR) and 95% confidence intervals (CI) derived from logistic regression models based on the method of generalized estimating equations.

Results: Of the 177?622 twins analyzed, 87% (n?=?154?531) presented as vertex-vertex. Fifty-five per cent (n?=?97?692) of twins were both delivered vaginally, 41% (n?=?72?825) were both delivered by Cesarean section and, of the remaining 4% (n?=?7105), the first twin was delivered vaginally and the second by Cesarean section. Twins with vertex–breech presentations delivered by Cesarean–cesarean sections, as well as those with vertex–vertex presentations delivered vaginally, had the lowest neonatal mortality rate (1.6 per 1000 live births). The highest neonatal mortality rate in the vertex–breech pairs occurred with vaginal–Cesarean deliveries (2.7 per 1000 live births). Among twins with vertex–vertex presentations, twins delivered via the vaginal–Cesarean route experienced the highest neonatal mortality (3.8 per 1000 live births). The RR for neonatal mortality in this group was 2.24 (95% CI 1.35, 3.72) compared with twins both delivered vaginally.

Conclusion: Route of delivery and fetal presentation both confer an impact on twin infant mortality rates. Strategies to reduce discordant routes in complicated vaginal deliveries may lead to improved neonatal survival.