利用光合细菌进行微生物修复：一种降低辛硫磷在养殖水中积累的低成本方法

【背景】中国是农业生产大国,渔林农牧占比庞大。有机农药无论在畜牧业还是水产养殖业都有广泛的应用。有机磷农药(Organophosphorus Pesticide,OP)是应用最广泛的有机农药,具有低毒和不易残留的优点。OP在水体中大量积累可通过生物富集作用间接影响人体健康,由此产生的生殖毒性不容忽视。光合细菌作为环境友好型水体有益菌,部分菌种具有降解有机农药的功能。【目的】自上海海洋大学明湖中分离纯化得到一株光合细菌(编号SPZ)。探究其对辛硫磷的耐受程度及降解效果,为养殖水体中有机磷农药的生物降解提供目的菌株。【方法】利用16S rRNA基因序列分析方法对目标菌株进行种属鉴定;利用紫外分光光度法测定分离菌株SPZ和标准菌株ST在不同接种量下的OD660并测定实验周期内光合细菌在不同浓度辛硫磷中OD660的变化趋势,以示辛硫磷对光合细菌的毒性作用;利用高效液相色谱法(High Performance Liquid Chromatography,HPLC)测定菌株对水体辛硫磷的降解能力;通过HPLC测定加热致死菌与活菌对水体辛硫磷的降解能力,确定菌株对辛硫磷的降解方式。【结果】16S r...     

利用黑斑双鳍电鳐构建实验性自身免疫性重症肌无力小鼠模型

目的建立符合国际化的临床前实验标准的实验性自身免疫性重症肌无力(experimental autoimmune myasthenia gravis, EAMG)动物模型。方法参照文献报道的方法并改进后,从电鳐电器官提取乙酰胆碱受体(acetylcholine receptor,AchR)蛋白纯品,并采用SDS凝胶电泳蛋白定性鉴定及BCA法蛋白定量;用纯化的蛋白主动免疫C57BL/6小鼠,共免疫3次(分别于第1天、第30天、第60天),进行EAMG小鼠临床评分、体重、血清AchR抗体含量、新斯的明试验、肌电图等综合评价。结果 EAMG模型组与佐剂组比较,自第三周开始发病,平均临床评分显著上升(P<0.01);发病小鼠体重显著减轻(P<0.01);新斯的明试验阳性;血清AchR抗体含量明显增加(P<0.01);肌电图重复电刺激实验阳性。结论从黑斑双鳍电鳐的电器官提取、纯化AchR蛋白成功诱导C57BL/6 EAMG小鼠模型,为进一步研究重症肌无力创造了良好条件。     

The origin of a novel kind of reassortant (H1N2) of influenza A virus

Genetic analysis of three H1N2 viruses indicated that only HA genes of H1N2 viruses were similar to that of A/Guangdong/6/91(H1N1) virus (PR8-like strain), while the other seven genes of them were similar to those of H3N2 virus circulating in man in 1995. Therefore, it could be considered that the H1N2 viruses were derived from reassortment between PR8-like strain and H3N2 virus circulating in man in 1995. However, the genomes of H1N2 viruses were very similar to each other. So the H1N2 viruses isolated in 1998 were not derived from new reassortment between PR8-like strain and H3N2 virus circulating in man in 1998, but derived from the evolution of H1N2 virus found in 1995.     

MicroRNA‐30c suppresses the pro‐fibrogenic effects of cardiac fibroblasts induced by TGF‐β1 and prevents atrial fibrosis by targeting TGFβRII

Atrial fibrosis serves as an important contributor to atrial fibrillation (AF). Recent data have suggested that microRNA‐30c (miR‐30c) is involved in fibrotic remodelling and cancer development, but the specific role of miR‐30c in atrial fibrosis remains unclear. The purpose of this study was to investigate the role of miR‐30c in atrial fibrosis and its underlying mechanisms through in vivo and in vitro experiments. Our results indicate that miR‐30c is significantly down‐regulated in the rat abdominal aortic constriction (AAC) model and in the cellular model of fibrosis induced by transforming growth factor‐β1 (TGF‐β1). Overexpression of miR‐30c in cardiac fibroblasts (CFs) markedly inhibits CF proliferation, differentiation, migration and collagen production, whereas decrease in miR‐30c leads to the opposite results. Moreover, we identified TGFβRII as a target of miR‐30c. Finally, transferring adeno‐associated virus 9 (AAV9)‐miR‐30c into the inferior vena cava of rats attenuated fibrosis in the left atrium following AAC. These data indicate that miR‐30c attenuates atrial fibrosis via inhibition of CF proliferation, differentiation, migration and collagen production by targeting TGFβRII, suggesting that miR‐30c might be a novel potential therapeutic target for preventing atrial fibrosis.     

不同碳源对生防荧光假单胞菌2P24产抗生素2,4-二乙酰基间苯三酚的影响

【目的】包括碳源代谢等不同环境因子可调控生防菌株生防相关因子表达,进而影响其防病效果。荧光假单胞菌2P24可防治多种植物病原真菌、细菌引起的土传病害,抗生素2,4-二乙酰基间苯三酚(2,4-diacetylphoroglucinol,2,4-DAPG)是其主要生防因子之一。本文利用平板对峙法及遗传学方法研究不同碳源对菌株2P24产生2,4-DAPG的影响及相关的调控途径。【方法】利用平板对峙法检测了菌株2P24在添加葡萄糖、果糖和蔗糖等碳源的土豆浸液培养基中对棉花立枯丝核菌(Rhizoctonia solani)的拮抗能力及菌株2P24中影响2,4-DAPG产生的相关基因的表达。另外,利用Tn5转座子对含有2,4-DAPG合成基因phl A报告质粒p970Gm-phl Ap的野生型菌株2P24进行随机突变,在果糖土豆浸液培养基中筛选提高phl A基因表达的突变菌株。【结果】平板对峙实验表明,菌株2P24以葡萄糖为碳源时其抑菌活性最强,蔗糖次之,而以果糖等为碳源时菌株2P24无抑菌活性;转录融合实验进一步表明葡萄糖可促进phl A基因的表达,果糖则不影响phl A基因的表达。在果糖土豆浸液培养基中,转座子随机突变实验获得了5株可明显提高phl A基因表达的突变菌株。Tn5插入位点和序列分析显示其中一个突变体是Tn5破坏了che B基因。转录检测表明与野生菌株相比,che B突变体中phl A基因的表达和2,4-DAPG的前体物质间苯三酚(phloroglucinol,PG)产量都显著提高。游动性实验发现突变che B基因可显著降低该菌株的游动性。【结论】上述结果表明菌株2P24中不同碳源在转录水平上可影响phl A基因的表达,进而影响2,4-DAPG产生。遗传学结果也显示,che B基因参与调控2,4-DAPG生物合成过程。     

筛选转基因动物的新方法——PCR及其产物测序法

用特异性引物对肌球蛋白轻链2启动子(myosin light chain-2,MLC₂)-糜酶融合基因的转基因新生鼠鼠尾DNA进行PCR筛选, 低熔点琼脂糖凝胶电泳回收阳性样品PCR所扩出的DNA条带,纯化后用同一对引物中的一个进行单引物PCR测序,与所转外源基因序列比较,进一步确定整合有外源基因的阳性鼠.PCR及PCR 产物测序法检测转基因动物具有操作方便,灵敏度高及特异性强等优点.     

Spatiotemporal Cluster Patterns of Hand,Foot, and Mouth Disease at the County Level in Mainland China, 2008-2012

Background

Hand, foot, and mouth disease (HFMD) is known to be a highly contagious childhood illness. In recent years, the number of reported cases of HFMD has significantly increased in mainland China. This study aims at the epidemiological features, spatiotemporal patterns of HMFD at the county/district level in mainland China.

Methods

Data on reported HFMD cases for each county from 1 January 2008 to 31 December 2012 were obtained from the Chinese Center for Disease Control and Prevention. Cluster analysis, spatial autocorrelation, and retrospective scan methods were used to explore the spatiotemporal patterns of the disease.

Results

The annual incidences varied greatly among the counties, ranging from 0 to 74.31‰ with the median of 5.42‰ (interquartile range: 1.54‰–13.55‰) during 2008–2012 in mainland China. Counties close to provincial capital cities generally had higher incidences than rural counties. A seasonal distribution was observed between the northern and southern China, of which dual epidemic were shown in southern China and usually only one in northern China. Based on the global and local spatial autocorrelation analysis, we found that the spatial distribution of HFMD was presented a significant clustering pattern for each year (P<0.001), and hotspots of the disease were mostly distributed in coastal provinces of China. The retrospective scan statistic further identified the dynamics of spatiotemporal clustering areas of the disease, which were mainly distributed in the counties of eastern and southern China, as well as provincial capitals and their surrounding counties.

Conclusions

The spatiotemporal clustering areas of the disease identified in this way were relatively stable, and imminent public health planning and resource allocation should be focused within those areas.     

绝经年龄的变化与遗传力的研究

1986年8月至1987年4月,调查了内蒙古呼和浩特市8556名汉、蒙、回族妇女的绝经年龄。市区平均绝经年龄汉族为50.57±0.13岁,蒙族为50.47±0.19岁,回族为50.76±0.20岁,三民族间无显著差异。呼市郊区汉族为50.71±0.17岁,与市区汉族(50.59±0.13岁)无显著差异。汉族平均绝经年龄在近30年间推迟约4年左右,平均每10年延迟1.3岁。母女成对对比表明,女儿平均绝经年龄比母亲推迟1.81岁。母女间绝经年龄有显著相关r=0.4599,遗传力为0.7006。每人的初潮年龄与绝经年龄无显著相关。子女多的妇女平均绝经年龄晚。     

细菌侵染的两种鲤鱼病生理反应及抗病性分析

通过人工接种嗜水气单胞菌(A.hydrophila)对受到细菌侵染的鲤鱼两个品种松浦鲤和德国镜鲤的病生理进行检测和分析,并采用DDRT-PCR方法对两种鲤的明显的抗感病个体基因差异进行初步分析。对血红蛋白(Hb)、红细胞(RBC)、血小板(PLT)、白细胞(WBC)记数,尿素氮(BUN)、白蛋白(ALB)、总蛋白(TP)、谷丙转氨酶(ALT)、甘油三酯(TG)、胆固醇(TC)、血糖(GLU)等生理生化指标进行了检测。人工接种试验表明,松浦鲤具有较强的抗病性,而德国镜鲤抗病性很差而感病性很强。DDRT-PCR结果表明,抗性基因在不同的鲤鱼群体之间及同种鲤鱼群体的不同抗感病个体之间表达水平不同。生理生化指标的变化反映出这两种鲤的抗性差异,在外来致病菌的刺激下,实验鲤体内的生理生化水平发生了变化,其中一些生化指标如谷丙转氨酶和总蛋白大幅度下降,其它生理指标表现出上升的趋势。总之松浦鲤在面对致病菌的侵染时从表型到生理生化水平上均表现出较强的抗病性。     

On Method of Moments Estimation in Linear Mixed Effects Models with Measurement Error on Covariates and Response with Application to a Longitudinal Study of Gene-Environment Interaction

We study a linear mixed effects model for longitudinal data, where the response variable and covariates with fixed effects are subject to measurement error. We propose a method of moment estimation that does not require any assumption on the functional forms of the distributions of random effects and other random errors in the model. For a classical measurement error model we apply the instrumental variable approach to ensure identifiability of the parameters. Our methodology, without instrumental variables, can be applied to Berkson measurement errors. Using simulation studies, we investigate the finite sample performances of the estimators and show the impact of measurement error on the covariates and the response on the estimation procedure. The results show that our method performs quite satisfactory, especially for the fixed effects with measurement error (even under misspecification of measurement error model). This method is applied to a real data example of a large birth and child cohort study.