Loss of function,missense, and intronic variants in NOTCH1 confer different risks for left ventricular outflow tract obstructive heart defects in two European cohorts

Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.     

Ligustrazine inhibits high voltage-gated Ca~(2+) and TTX-resistant Na~+ channels of primary sensory neuron and thermal nociception in the rat:a study on peripheral mechanism

Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat.     

试论加强国际合作与促进我国医学伦理学教育的发展

原北京医科大学(现为北京大学医学部)从20世纪90年代初开始,积极寻求与美国中华医学基金会的合作以促进医学伦理学的学科发展和国际化水平的提高。十几年来,北京大学医学部作为基地和依托极大地支持和引领了我国医学伦理学的教学改革与发展,增强了相关人员的医学伦理意识以及医学伦理学理论对实践的指导作用,促进了伦理学知识和能力的培训,提升了我国生物医学科研伦理的实力,奠定了医学伦理学继续教育的基础,使医学伦理学实现了系统性和跨越式的发展。     

bevacizumab治疗乳腺癌的基础和临床研究

分子靶向药物bevacizumab是针对血管内皮生长因子(VEGF)的重组人源化单克隆抗体,在多种恶性肿瘤的治疗中显示了临床效果。现就bevacizumab的作用机制及其在乳腺癌治疗中的临床研究进展作一综述。     

庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响

目的：研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1（insulin-like growth factor-1，IGF-1）及其受体（insulin-like growth factor-1 receptor，EGF-1R）表达的影响，并探讨其生物学特性。方法：采用免疫组织细胞化学方法，以抗IGF-1及IGF-1R抗体为标记物，检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点；采用Brdu体内标记和抗Brdu抗体免疫组化染色，检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果：IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达，庆大霉素损伤后，其表达增多。在1d组IGF-1及IGF-1R表达最强，其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞，7d组最多。结论：庆大霉素损伤后，豚鼠前庭上皮IGF-1及IGF-1R表达增强，其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。     

铁路系统医院136篇口腔修复、正畸学论文的统计分析

通过对铁路系统医院１３６篇口腔修复、正畸学论文的统计分析，来评价医院口腔修复、正畸的科研水平，同时也揭示了科研工作中存在的问题。指出只有加强科研协作、扩大学术交流、增加科研投入，提高科研水平，使科研成果更趋完善。     

48例易性癖患者围手术期的心理护理

目的：探讨易性癖患变性手术的心理状态。方法：对48例易性癖患行变性手术前后实施有针对性的心理护理。结果：有效的心理护理能进一步改善变性手术患的心理状态，促进易性癖患心理康复。结论：针对易性癖这一特殊群体，开展积极有效的心理护理，对不良心理的康复至关重要。     

套式PCR检测细菌16SrRNA基因

目的　应用套式PCR建立快速检查方法来检测血液中是否含有细菌。方法　采用细菌 1 6SrRNA基因通用引物 ,通过套式PCR方法对细菌进行扩增 ,并对其灵敏度、特异性作一评价。结果　临床常见细菌扩增反应为阳性 ,其他病原微生物及人类基因组DNA为阴性。结论　本法具有敏感、快速、特异、准确的优点 ,是一种可靠的实验手段