江苏省血吸虫病传播阻断地区流行因素监测和评价

目的了解血吸虫病传播阻断后流行因素及其特点,评价和探讨巩固监测阶段的措施与对策。方法在29个经省考核达到血吸虫病传播阻断标准的县（市、区）开展监测研究,对传染源、钉螺等流行因素进行纵向观察,并对不同的监测方法进行比较研究。结果1传染源监测表明,居民COPT阳性率为0．21％,无当地感染的粪阳病人及低年龄病例,家畜监测查病均为阴性;外来人口中COPT阳性率显著高于当地居民,外来及本地外出人口中均查获粪阳病例。2在开始监测的头5年内出现77．3％的有螺环境：查出钉螺分布在其中的16个县（市、区）,占55．17％;有螺环境多为小面积复杂环境,有螺原因主要是查灭螺质量较差,同时外来扩散也不容忽视。3监测查螺方法中,以“定点查”检出率最高。结论1血吸虫病传播阻断地区疫情稳定,内源性传染源得到了有效控制,但再流行因素依然存在;2巩固监测时期,病情监测主要抓好重点流动人群和指示人群（小年龄人群）;钉螺监测在近期注重历史有螺环境,远期可注重外来输入,监测方法建议采用“定点查”结合“轮查”。     

Octopamine is the synaptic transmitter between identified neurons in the buccal feeding network of the pond snail Lymnaea stagnalis

We report the pharmacological properties of synaptic connections from the three octopamine-containing OC interneurons to identified buccal feeding neurons in the pond snail, Lymnaea stagnalis. Intracellular stimulation of an OC interneuron evokes inhibitory postsynaptic potentials in the B3 motoneurons and N2 (d) interneurons, while the synapse between OC and N3 (phasic) interneurons has two components: an initial electrical excitation followed by chemical inhibition. All synaptic responses persist in a saline with elevated calcium and magnesium suggesting that the connections are monosynaptic. Local perfusion of 10⁻⁴ M octopamine produces the same inhibitory membrane responses from these buccal neurons as OC stimulation. These responses also persist in high Mg²⁺/Ca²⁺ saline indicating direct membrane effects. The similarities in reversal potentials for the synaptic hyperpolarization evoked on B3 neurons after OC stimulation (−89.0 mV, S.E.M.=14.1, n=10) and the octopamine response of the B3 neurons (−84.7 mV, S.E.M.=6.6, n=6) indicate that increased K⁺-conductance underlies both responses. Bath application of the octopaminergic drugs phentolamine (10⁻⁶ M), epinastine (10⁻⁶ M) or DCDM (10⁻⁴ M) blocks the inhibitory synapse onto B3 or N2 neurons and the chemical component of the N3 response. They also block the octopamine-evoked inhibition of B3, N2 and N3 neurons. NC-7 (2×10⁻⁵ M) has a hyperpolarizing agonist effect (like octopamine) on these neurons and also blocks their chemical synaptic input from the OC interneurons. These results provide pharmacological evidence that the neurotransmitter between the octopamine-immunopositive OC interneurons and its followers is octopamine. This is the first example of identified octopaminergic synaptic connections within the snail CNS.     

First egg protein with a neurotoxic effect on mice

While many invertebrates sequester toxic compounds to endow eggs with chemical defences, here we show, for the first time to our knowledge, the identification of a neurotoxin of proteinaceous nature localized inside an egg. Egg extracts from the freshwater apple snail Pomacea canaliculata displayed a neurotoxic effect in mice upon intraperitoneal injection (i.p.) (LD50, 96h 2.3mg/kg). Egg protein and total lipids were analysed separately and the only fraction displaying a highly toxic effect (LD50, 96h 0.25mg/kg, i.p.) was further purified to homogeneity as an oligomeric glyco-lipoprotein of 400kDa and two subunits biochemically and immunologically indistinguishable from the previously described perivitellin PV2. The neurotoxin was heat sensitive and there was evidence of circulating antibody response to sublethal i.p. doses on mice. Clinical signs, histopathological and immunocytochemical studies revealed damage mostly in mice spinal cord. Experiments showed chromatolysis and a decreased response to calbindin D-28K associated with a significant increase of TUNEL-positive cells in the dorsal horn neurons. These results suggest that calcium buffering and apoptosis may play a role in the neurological disorders induced by the toxin in mammalian central nervous system. This is the first report of a mollusc neurotoxin genetically encoded outside the cone-snail species.     

非小细胞肺癌组织中Snail、E-cadherin及N-cadherin的表达及临床意义

目的探讨指转录因子Snail、上皮细胞钙粘蛋白(E-cadherin)及神经钙黏素(N-cadherin)在非小细胞肺癌组织中的表达及其之间的相关性。方法采用免疫组化法检测63例非小细胞肺癌(NSCLC)手术切除标本及30例癌旁组织中Snail、E-cadherin、N-cadherin蛋白的表达,并分析相互间关系及其临床意义。结果与癌旁组织比较,NSCLC组织中E-cadherin表达显著减少,N-cadherin和Snail表达明显增加(P<0.01)。NSCLC组织中,Snail的表达与N-cadherin呈明显的正相关(P<0.05,r=0.33),与E-cadherin呈显著负相关(P<0.05,r=-0.41),N-cadherinl的表达与E-cadheri也呈明显负相关(P<0.05,r=-0.56)。Snail表达阳性率与TNM分期和有无转移相关(P<0.05);E-cadherin表达阳性率与TNM分期和有无转移相关(P<0.05);N-cadherin表达阳性率与组织学分型、TNM分期和有无转移相关(P<0.05)。结论 NSCLC癌组织中Snail、E-cadherin和N-cadherin表达水平与肿瘤的浸润转移密切相关,可作为临床诊断和治疗靶点的参考指标。     

武汉市综合治理垸内钉螺孳生地效果及效益分析

目的对武汉市垸内综合治理控制血吸虫病流行的效果及费用效益进行分析,为决策和评价提供科学依据。方法根据不同地理特点,以环境改造为主,采用沟渠硬化、开新填旧、建鱼池等方法,辅以药物杀灭对垸内钉螺孳生地进行全面综合治理。收集治理前后螺情、人畜病情以及项目费用、疫区经济状况等相关资料,计算螺情、病情指标下降率以及单位效果费用、净效益、费用效益比,进行防治效果评价和费用-效果、费用-效益分析。结果经综合治理,全市有螺处数、有螺面积分别下降了79．93％,85．73％;垸内各流行村人群粪检阳性率下降了58．82％;耕牛粪检阳性率下降了73．14％。项目血防综合效果指数为71．50,费用效益比为1：2．92,净效益费用比为1．92。结论垸内钉螺孳生地综合治理,有效控制了血吸虫病流行,是湖沼型垸内亚型地区控制并消灭血吸虫病的有效对策和措施。     

pEGFP-C1-STAT3真核表达载体的构建及其在SGC7901细胞株中对Snail表达的影响

目的研究信号转导与转录激活因子3（STAT3）基因转染人胃癌细胞株SGC7901后,对锌指转录因子Snail1（Snail）及切除修复交叉互补基因1（excision repair cross complementation group 1,ERCC1）表达的影响。方法利用基因重组技术构建重组pEGFP-C1-STAT3真核表达载体;脂质体介导转染技术转染胃癌细胞株SGC7901,荧光显微镜、Western blot 检测转染后SGC7901细胞株中STAT3、pSTAT3、Snail及ERCC1的表达,流式细胞仪检测转染后顺铂处理下细胞凋亡率。结果重组质粒经Hind Ⅲ、SacⅡ双酶切测序与STAT3基因序列一致;利用脂质体介导将pEGFP-C1-STAT3重组质粒转染SGC7901细胞株,获得了STAT3基因表达,Western blot 检测pSTAT3、Snail、ERCC1表达增高,具有统计学意义,流式细胞术分析显示转染重组质粒pEGFP-C1-STAT3后,细胞在顺铂作用下的早期凋亡率减低。结论成功构建STAT3重组质粒并转入中分化胃腺癌细胞株SGC7901后,细胞Snail及ERCC1显著增高,细胞对顺铂敏感度下降。     

沉默LIMK1抑制人结肠癌SW480细胞上皮-间质转化

目的:研究沉默LIMK1对人结肠癌SW480细胞上皮-间质转化（epithelial-mesenchymal transformation,EMT）的影响。方法:RT-PCR、Western blot、免疫荧光与免疫组化检测沉默LIMK1对EMT相关分子表达的影响。裸鼠实验检测沉默LIMK1对移植瘤生长的影响。结果:RT-PCR检测显示,沉默LIMK1可下调Vimentin和上调E-cadherin mRNA表达(P<0.05)。Western blot显示,沉默LIMK1可明显下调SW480细胞Snail及Vimentin蛋白表达和上调E-cadherin表达(P<0.05)。免疫荧光显示,LIMK1沉默细胞Snail与Vimentin阳性信号较对照组明显减弱,而E-cadherin阳性信号显著增强。裸鼠实验结果显示,沉默组肿瘤生长速度较SW480组明显减慢(P<0.05)。沉默组移植瘤瘤重（0.16±0.079）g较SW480组（0.86±0.165）g明显减少,瘤重抑制率为97.7%(P<0.05)。LIMK1沉默组移植瘤较对照组的Ki-67、Vimentin、Snail与CD34阳性表达明显减弱,而E-cadherin表达明显增加。结论:沉默LIMK1可体外抑制人结肠癌SW480细胞EMT。     

Sex steroid receptor evolution and signalling in aquatic invertebrates

In vertebrate reproductive endocrinology sex steroids play a pivotal role via binding to receptors. However, information on the origin and relevance of sex steroids in invertebrates is limited. This review highlights current literature on steroid receptors in aquatic invertebrates and reports on some new findings. It has been shown that invertebrates of the deuterostome clade, such as Acrania and Echinodermata, respond to estrogens and androgens and, at least in Branchiostoma, an estrogen receptor has been cloned. Within the protostomes, most findings are related to aquatic molluscs. Sex steroid receptor-like proteins are abundant in gastropods, bivalves and cephalopods and also sex hormone signalling shows partial similarity to the deuterostomes. In ecdysozoans, however, the impact of sex steroids is still a matter of debate even though there is evidence on the presence of estrogen receptor-like proteins in Crustacea and on physiological effects of estrogens in both Nematoda and Crustacea. Recent findings suggest the presence of an estrogen receptor α-like protein of unclear physiological role in Gammarus fossarum (Crustacea). Binding studies revealed the crustacean Hyalella azteca to possess specific binding sites only for androgens but not for estrogens suggesting a possible limitation to functional androgen receptors in this species. Further studies have to be conducted to shed more light into the discussion about the controversy about sex steroid receptors in invertebrates.