云南高黎贡山地区蝴蝶群落多样性

位于滇西北的高黎贡山是全球生物多样性研究和保护的热点地区之一, 然而该地区昆虫多样性缺乏系统调查和总结。本研究聚焦蝴蝶类群, 考虑该区域高山峡谷特点, 结合海拔梯度、生境类型和季节变化, 采用样线法调查、分析蝴蝶物种多样性及群落结构变化。结果显示: 共观测记录到蝴蝶2,055只, 隶属于5科85属151种, 在历史记录上新增27种, 使该地区已知蝴蝶种类达488种; 其中蛱蝶科物种多样性最高, 灰蝶科次之, 凤蝶科最低。蝴蝶群落多样性分析结果表明: 中海拔1,000-2,000 m区域种类丰富、多样性指数最高; 低海拔区蝴蝶分布明显聚集, 并且与高海拔地区空间上分离, 少有重叠。该地区不同生境中蝴蝶的种类及数量差异也较大, 物种数及多样性指数在自然保护区最高、边缘交错带居中及农业种植区最低。此外, 蝴蝶的种类和数量也存在季节差异, 春季调查到的个体数少, 夏季观察到的物种数少, 两年秋季调查到的物种丰富度、多样性均高, 但存在季节内变化。总之, 高黎贡山地区不同海拔、生境、季节间和季节内蝴蝶群落组成有自身特点, 共存物种有限, 蝴蝶群落相似性低。综合评估分布于该地区的蝴蝶保护种类, 包括易危种17种、近危种50种, 有国家二级保护蝴蝶3种。本研究弄清了高黎贡山地区蝴蝶的物种本底, 并调查获得其多样性随海拔、生境和季节变化的模式, 为加强区域物种多样性监测、保护生物多样性提供了科学依据。     

小鼠阴道菌群紊乱模型的建立

目的建立小鼠阴道菌群紊乱模型,为调整阴道菌群紊乱的药物研发提供模型参考。方法采用雌激素化的C57BL/6小鼠经阴道以不同处理方式(链霉素50μg/只,加德纳菌50μL/只,链霉素50μg/只+抗链霉素加德纳菌50μL/只,每种处理方式各70只/组)诱导小鼠阴道菌群紊乱模型,采用细菌16S rDNA高通量测序考察造模后第1、第2、第3、第5、第7、第9、第11天内加德纳菌在阴道内的定植情况,以及阴道细菌结构和细菌生物多样性,并通过显微镜观察阴道组织的病理改变,比较3种造模方法的差异。另采用阳性药物(定君生,成分为德氏乳杆菌)对模型进行验证。结果采用链霉素联合抗链霉素加德纳菌能诱导形成典型的阴道菌群紊乱模型,造模后可见加德纳菌在阴道内的定植增多,优势菌以铜绿假单胞菌为主,且阴道细菌生物多样性增加,阴道组织可见明显的炎症浸润和上皮细胞坏死等病理改变。定君生能显著减少加德纳菌在阴道内的定植,减少阴道内的细菌生物多样性,并能显著改善阴道组织病理变化。结论采用链霉素联合抗链霉素加德纳菌诱导的小鼠阴道菌群紊乱模型方法更佳,模型的细菌学和组织病理学改变,以及对药物的反应性与临床有一定相似,具有临床应用价值。     

来源卤化二型聚酮类生物合成基因簇的两种关键功能基因鉴定与表达

为催化卤化产物,挖掘具有生物活性的新卤化物提供新的方法途径,拟构建卤化酶原核表达载体催化天然卤化物的卤化过程。对链霉菌Streptomyces sp. FJS31-2基因组中一个II型PKS类产物zunyimycin生物合成基因簇进行系列分析,针对其中的后修饰酶卤化酶基因和单加氧酶基因进行原核表达纯化。通过分子生物学手段成功构建卤化酶基因(65 kD)和单加氧酶基因(37 kD)的原核表达载体,并对其进行鉴定。卤化酶和单加氧酶在催化化合物的卤化过程中,会产生疑似新卤化产物。     

Molecular epidemiology and recombination of Enterovirus A71 in mainland China from 1987 to 2017

International Microbiology - Enterovirus A71 (EV-A71) is an important pathogen of severe hand, foot, and mouth disease (HFMD) in young children. This study aimed to retrospectively analyze the...     

GABAB receptor inhibits tumor progression and epithelial-mesenchymal transition via the regulation of Hippo/YAP1 pathway in colorectal cancer

Gamma-Aminobutyric Acid Type B Receptor (GABABR) plays essential roles in tumor progression. However, the function of GABABR in colorectal cancer (CRC) needs further clarification. As the main part of GABABR, GABABR1 expression was identified significantly lower in tumor tissues than those in non-tumor normal tissues and that CRC patients with high GABABR1 expression lived longer. Further studies indicated that knockdown of GABABR1 elevated CRC cell proliferation, migration, and invasion. Furthermore, knockdown of GABABR1 activated the expression of the epithelial-mesenchymal transition (EMT)-related proteins N-cadherin and Vimentin, whereas decrease the protein level of E-cadherin. In addition, activation of Hippo/YAP1 signaling contributes to the GABABR1 down-regulation promoted proliferation, migration, invasion and EMT in CRC cells. At last, we verified the contribution of Hippo/YAP1 signaling in the GABABR1 down-regulation impaired biological phenotype of colon cancer cells in vivo. In summary, these data indicate that GABABR1 impairs the migration and invasion of CRC cells by inhibiting EMT and the Hippo/YAP1 pathway, suggesting that GABABR1 could be a potential therapeutic target for CRC.     

Prevalence and prediction of Lyme disease in Hainan province

Lyme disease (LD) is one of the most important vector-borne diseases worldwide. However, there is limited information on the prevalence and risk analysis using correlated factors in the tropical areas. A total of 1583 serum samples, collected from five hospitals of Hainan Province, were tested by immunofluorescence assay (IFA) and western blot (WB) analyses using anti-Borrelia burgdorferi antibodies. Then, we mapped the distribution of positive rate (by IFA) and the spread of confirmed Lyme patients (by WB). Using ArcGIS, we compiled host-vector-human interactions and correlated data as risk factor layers to predict LD risk in Hainan Province. There are three LD hotspots, designated hotspot I, which is located in central Hainan, hotspot II, which contains Sanya district, and hotspot III, which lies in the Haikou-Qiongshan area. The positive rate (16.67% by IFA) of LD in Qiongzhong, located in hotspot I, was higher than that in four other areas. Of confirmed cases of LD, 80.77% of patients (42/52) whose results had been confirmed by WB were in hotspots I and III. Hotspot II, with unknowed prevalence of LD, need to be paid more attention considering human-vector interaction. Wuzhi and Limu mountains might be the most important areas for the prevalence of LD, as the severe host-vector and human-vector interactions lead to a potential origin site for LD. Qiongzhong is the riskiest area and is located to the east of Wuzhi Mountain. In the Sanya and Haikou-Qiongshan area, intervening in the human-vector interaction would help control the prevalence of LD.     

Morphogenesis and Molecular Phylogeny of a New Freshwater Ciliate,Notohymena apoaustralis n. sp. (Ciliophora,Oxytrichidae)

The live morphology, infraciliature, and morphogenesis of a new oxytrichid ciliate, Notohymena apoaustralis n. sp. collected from a freshwater pond in Qingdao (Tsingtao), China, were studied in vivo and after protargol impregnation. Notohymena apoaustralis n. sp. is characterized as follows: undulating membranes in Notohymena‐pattern; cortical granules yellow‐green, grouped around the marginal cirri and dorsal bristles, and in short irregular rows elsewhere in the cell; single contractile vacuole positioned at anterior 1/3 of the body length; two macronuclear nodules and one micronucleus; about 39 adoral membranelles; 18 frontoventral transverse cirri in typical Oxytricha‐pattern; one right and one left marginal row, almost confluent posteriorly; dorsal ciliature in typical Oxytricha‐pattern; 8–10 caudal cirri arranged in three rows, one each at the posterior end of dorsal kineties 1, 2, and 4, indistinguishable from marginal cirri in life. The morphogenetic process in N. apoaustralis n. sp. is consistent with that of the type species, Notohymena rubescens Blatterer and Foissner, 1988. Phylogenetic analyses based on small subunit rDNA sequence data suggest a sister relationship between N. apoaustralis n. sp. and Paraurostyla weissei, which cluster in a clade with Rubrioxytricha ferruginea.     

Suppression of Grb2 expression improved hepatic steatosis, oxidative stress, and apoptosis induced by palmitic acid in vitro partly through insulin signaling alteration

In this study, we aimed to study the role of growth factor receptor-bound protein 2 (Grb2) in palmitic acid-induced steatosis and other “fatty liver” symptoms in vitro. HepG2 cells, with or without stably suppressed Grb2 expression, were incubated with palmitic acid for 24 h to induce typical clinical “fatty liver” features, including steatosis, impaired glucose metabolism, oxidative stress, and apoptosis. MTT and Oil Red O assays were applied to test cell viability and fat deposition, respectively. Glucose uptake assay was used to evaluate the glucose utilization of cells. Quantitative polymerase chain reaction and Western blot were used to measure expressional changes of key markers of insulin signaling, lipid/glucose metabolism, oxidative stress, and apoptosis. After 24-h palmitic acid induction, increased fat accumulation, reduced glucose uptake, impaired insulin signaling, enhanced oxidative stress, and increased apoptosis were observed in HepG2 cells. Suppression of Grb2 in HepG2 significantly reduced fat accumulation, improved glucose metabolism, ameliorated oxidative stress, and restored the activity of insulin receptor substrate-1/Akt and MEK/ERK pathways. In addition, Grb2 deficiency attenuated hepatic apoptosis shown by reduced activation of caspase-3 and fluorescent staining. Modulation of Bcl-2 and Bak1 also contributed to reduced apoptosis. In conclusion, suppression of Grb2 expression in HepG2 cells improved hepatic steatosis, glucose metabolism, oxidative stress, and apoptosis induced by palmitic acid incubation partly though modulating the insulin signaling pathway.