P2X(7) receptors are expressed during mouse nephrogenesis and in collecting duct cysts of the cpk/cpk mouse.

BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings.     

荧光原位杂交技术分析人结肠菌群方法研究

建立荧光原位杂交技术分析人体内结肠菌群的方法。取受试者新鲜粪便 ,选用 5种特异性的 16SrRNA寡核苷酸探针 ,检测粪便样本收集后的保存时间、温度 ,离心条件及样本固定液存放时间对杂交计数结果的影响。结果建立最佳实验条件为 :粪便样本收集后应尽快在 4℃下保存 ,放置时间不要超过 12小时即作处理 ;样本的适宜离心条件为 70 0g 2分钟 ;样本用多聚甲醛固定后在 - 80℃下存放时间不要超过 5个月。该方法具有较好的稳定性 ,可以有效地检出个体之间结肠菌群的差异。     

Central nervous system monitoring. What helps, what does not

The ICU monitoring of CNS function can make a difference in the clinical outcome. No single technique addresses the multiple issues that arise in the ICU setting, especially for the polytrauma patient. Multimodality approaches combining assessment of cerebral blood flow, electrophysiologic parameters, and intracranial pressure, when appropriate, with cardiac and respiratory monitors are being developed at a number of traumatology centers world wide. Experience needs to be gained to establish the best combination of these modalities. Pending this, selected use of intracranial pressure monitoring combined with EEG and transcranial Doppler ultrasound provides reliable immediate assessment and ongoing monitoring of CNS structures.     

Dislocation after hemiarthroplasty of the hip: a comparison of the dislocation rate after posterior and lateral approaches to the hip.

We compared the 3-month dislocation rate for hip hemiarthroplasties inserted via the posterior and direct lateral routes. In all, 2906 primary hemiarthroplasties, performed between 1986 and 1992 in four hospitals on a training hospital rotation, were analysed. The posterior approach was used in 1656 (57%) and the lateral in 1250 (43%). The groups were otherwise comparable. The overall dislocation rate for the posterior approach was 9.0% (149/1656), whereas that for the direct lateral approach was 3.3% (41/2150). The difference is statistically highly significant. In addition, we analysed the dislocation rate for each approach in the three broad groups of surgical trainee. For senior registrars, there was no statistical difference in the dislocation rate. However, for registrars and senior house officers, there were statistically highly significant differences in the dislocation rate for posterior and direct lateral approaches (8.4% vs 3.3% and 14.2% vs 3.6%, respectively). We conclude that, because of the high mortality associated with dislocation of a hemiarthroplasty, the posterior approach for this operation should now be abandoned, especially by surgical trainees early in their careers.