115例手足口病原学监测结果分析

目的:探讨长沙地区手足口病的病原学特征,为当地的疾病预防和控制提供科学依据.方法:使用肠道通用和EV71、CA16特异性引物,对2009年长沙市的115例手足口病患者的疱疹液、粪便、咽拭子标本,进行RT-PCR鉴定,并对手足口病疫情开展监测,采用流行病学方法对结果进行统计分析.结果:在采集到标本的115例患者中,84例患者检测结果为阳性,其中19例检测为EV71病毒核酸阳性(22.62%);30例检测CA16阳性(35.71%);35例检测到其他肠道病毒(41.67%).阳性标本中男女性别比为(1.27:1),发病年龄主要集中1-5岁儿童(90.47%),尤其是在3岁组(34.52%);发病季节主要集中于4-8月.结论:在长沙地区手足口病易发于1-5岁儿童,应在春夏季重点加强这一人群的预防和控制措施.     

Slit-Robo signaling mediates lymphangiogenesis and promotes tumor lymphatic metastasis

The Slit family of guidance cues binds to Roundabout (Robo) receptors to modulate neuronal, leukocytic, and endothelial migration. Slit-Robo signaling had been reported to function as chemoattractive signal for vascular endothelial cells during angiogenesis. In this study, we found that Robo1 was expressed in lymphatic endothelial cells to mediate the migration and tube formation of these cells upon Slit2 stimulation, which were specifically inhibited by the function-blocking antibody R5 to Slit2/Robo1 interaction. To further explore the lymphangiogenic effect and significance mediated by Slit-Robo signaling, we intercrossed Slit2 transgenic mice with a non-metastatic RIP1-Tag2 mouse tumor model, and found that transgenic overexpression of Slit2 significantly enhanced tumor lymphangiogenesis and subsequently promoted mesenteric lymph node metastasis of pancreatic islet tumors. Taken together, our findings reveal that through interacting with Robo1, Slit2 is a novel and potent lymphangiogenic factor and contributes to tumor lymphatic metastasis.     

DRR1 is expressed in the developing nervous system and downregulated during neuroblastoma carcinogenesis

Down-regulated in renal cell carcinoma 1 (DRR1) is mapped at 3p21.1, and is a candidate tumor suppressor gene. However, its biological roles have yet to be elucidated. Here, we developed polyclonal antibodies against DRR1 protein, and examined its expression during embryogenesis and carcinogenesis. The DRR1 protein was preferentially expressed in axonal projections of the central and peripheral nervous system of mice during embryonic days 10.5-16.5. Consistent with this expression pattern, the protein was detected in the neurites of primary cultured cortical neurons of rats at embryonic day 18.5. Survival of these cells was significantly inhibited by RNAi-induced downregulation of DRR1 expression. DRR1 was poorly expressed in established cancer cell lines, including neuroblastoma cells, whereas strong expression was observed in normal cells. A neuroblastoma model, MYCN transgenic mice, revealed that DRR1 protein was expressed in the celiac ganglion 2 weeks after birth when neuroblast hyperplasia was also observed; however, there was no longer any expression of DRR1 protein in tumors originating from the ganglion 8 weeks after birth. Together, our data indicate that DRR1 protein is expressed in normal cells, particularly in the nervous system during embryogenesis, is involved in neuronal cell survival, and is downregulated during neuroblastoma carcinogenesis.     

三个小麦春化基因的时空表达特性分析(英文)

为明确小麦春化基因的时空表达特性,以中国春和洛旱2号小麦品种为试验材料,利用半定量RT-PCR技术,分析了3个春化基因VERNALIZATION1(VRN1)、VRN2和VRN3的时空表达特性。结果表明,VRN1在中国春的三叶期叶片和根、灌浆期的茎秆和旗叶、花药、胚珠和发育的种子中均有不同程度的表达。在开花前,表达水平呈上升趋势,而花后呈降低的趋势,在干种子和萌发种子的胚芽中没有检测到表达;在洛旱2号中,除了在三叶期的叶片和根中没有检测到表达外,VRN1的表达特性与中国春有相同的趋势。VRN2只在三叶期的叶片和萌发种子的胚芽中表达,在其他检测的组织中没有表达;VRN3的表达与VRN1的时空表达特性相似,但在根中未检测到表达。这一结果为进一步分析普通小麦品种春化发育的分子调控机理提供了重要信息。     

Wounding induces resistance to pathogens with different lifestyles in tomato: role of ethylene in cross-protection

Many reports point to the existence of a network of regulatory signalling occurring in plants during the interaction with micro-organisms (biotic stress) and abiotic stresses such as wounding. However, the focus is on shared intermediates/components and/or common molecular outputs in differently triggered signalling pathways, and not on the degree and modes of effective influence between abiotic and biotic stresses nor the range of true plant-pathogen interactions open to such influence. We report on local and systemic wound-induced protection in tomato (Solanum lycopersicum L.) to four pathogens with a range of lifestyles (Botrytis cinerea, Fusarium oxysporum f.sp. lycopersici, Phytophthora capsici and Pseudomonas syringae pv. tomato). The role of ethylene (ET) in the phenomenon and in the induction by wounding of several markers of defense was investigated by using the never-ripe tomato mutant plants impaired in ET perception. We showed that PINIIb, PR1b, PR5, PR7 and peroxidase (POD) are influenced locally and/or systemically by wounding and, with the exception of POD activity, by ET perception. We also demonstrated that ET, although not essential, is positively (B. cinerea, P. capsici) or negatively (F. oxysporum, P. syringae pv. tomato) involved not only in basal but also in wound-induced resistance to each pathogen.