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Background@#Zika virus (ZIKV) has emerged as a global pathogen causing significant public health concerns. China has reported several imported cases where ZIKV were carried by travelers who frequently travel between China and ZIKV-endemic regions. To fully characterize the ZIKV strains isolated from the cases reported in China and assess the risk of ZIKV transmission in China, comprehensive phylogenetic and genetic analyses were performed both on all ZIKV sequences of China and on a group of scientifically selected ZIKV sequences reported in some of the top interested destinations for Chinese travelers.@*Methods@#ZIKV genomic sequences were retrieved from the National Center for Biotechnology Information database through stratified sampling. Recombination event detection, maximum likelihood (ML) phylogenetic analysis, molecular clock analysis, selection pressure analysis, and amino acid substitution analysis were used to reconstruct the epidemiology and molecular transmission of ZIKV.@*Results@#The present study investigated 18 ZIKV sequences from China and 70 sequences from 16 selected countries. Recombination events rarely happens in all ZIKV Asian lineage. ZIKV genomes were generally undergone episodic positive selection (17 sites), and only one site was under pervasive positive selection. All ZIKV imported into China were Asian lineage and were assigned into two clusters: Venezuela-origin (cluster A) and Samoa-origin cluster (cluster B) with common ancestor from French Polynesia. The time of most recent common ancestors of Cluster A dated to approximately 2013/11 (95% highest posterior density [HPD] 2013/06, 2014/03) and cluster B dated to 2014/08 (95% HPD 2014/02, 2015/01). Cluster B is more variable than Cluster A in comparison with other clusters, but no varied site of biological significance was revealed. ZIKV strains in Southeast Asia countries are independent from strains in America epidemics.@*Conclusions@#The genetic evolution of ZIKV is conservative. There are two independent introductions of ZIKV into China and China is in danger of autochthonous transmission of ZIKV because of high-risk surrounding areas. Southeast Asia areas have high risk of originating the next large-scale epidemic ZIKV strains.
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BACKGROUND@#Zika virus (ZIKV) has emerged as a global pathogen causing significant public health concerns. China has reported several imported cases where ZIKV were carried by travelers who frequently travel between China and ZIKV-endemic regions. To fully characterize the ZIKV strains isolated from the cases reported in China and assess the risk of ZIKV transmission in China, comprehensive phylogenetic and genetic analyses were performed both on all ZIKV sequences of China and on a group of scientifically selected ZIKV sequences reported in some of the top interested destinations for Chinese travelers.@*METHODS@#ZIKV genomic sequences were retrieved from the National Center for Biotechnology Information database through stratified sampling. Recombination event detection, maximum likelihood (ML) phylogenetic analysis, molecular clock analysis, selection pressure analysis, and amino acid substitution analysis were used to reconstruct the epidemiology and molecular transmission of ZIKV.@*RESULTS@#The present study investigated 18 ZIKV sequences from China and 70 sequences from 16 selected countries. Recombination events rarely happens in all ZIKV Asian lineage. ZIKV genomes were generally undergone episodic positive selection (17 sites), and only one site was under pervasive positive selection. All ZIKV imported into China were Asian lineage and were assigned into two clusters: Venezuela-origin (cluster A) and Samoa-origin cluster (cluster B) with common ancestor from French Polynesia. The time of most recent common ancestors of Cluster A dated to approximately 2013/11 (95% highest posterior density [HPD] 2013/06, 2014/03) and cluster B dated to 2014/08 (95% HPD 2014/02, 2015/01). Cluster B is more variable than Cluster A in comparison with other clusters, but no varied site of biological significance was revealed. ZIKV strains in Southeast Asia countries are independent from strains in America epidemics.@*CONCLUSIONS@#The genetic evolution of ZIKV is conservative. There are two independent introductions of ZIKV into China and China is in danger of autochthonous transmission of ZIKV because of high-risk surrounding areas. Southeast Asia areas have high risk of originating the next large-scale epidemic ZIKV strains.
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A strain, Pseudomonas sp. X-2-45, with high and stable lipolytical activity was screened by continuously subculturing a lipase-producing bacterium P. sp. LP-1 in culture medium containing Jatropha oil as a sole carbon source. Its hydrolytic activity was 29.79 U/mL, which was increased by 288% as compared to that of parent strain. Furthermore, the growth and lipase synthesis of X-2-45, its catalytic ability to hydrolyze vegetable oils, as well as ester synthesis between fatty acids and organic alcohols were studied. Results showed that rates of bacterial growth and lipase synthesis were significantly raised. Bacterial biomass and lipase activity reached the highest level after 30 h of incubation. Moreover, growth stationary period was prolonged and lipase produced exhibited good stability in culture media during incubation period. Hydro- lytic activity of P. sp. X-2-45 lipase toward Jatropha oil was increased by 378% as compared to parent strain, suggesting that acclimation to Jatropha oil was an effective approach for improving substrate selectivity oflipase. Finally, results of ester synthesis catalyzed by P. sp. X-2-45 lipase indicated that this lipase could catalyze esterification reactions between lauric acid and n-butanol, n-octanol, 1-dodecanol or glycerol, palmitic acid or stearic acid and methanol, n-octanol, 1-dodecanol or glycerol, oleic acid and methanol, n-butanol, n-octanol, 1-dodecanol or glycerol.
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Student preparation for laboratory sessions is the first step of conducting laboratory experiments. It makes students maximize use of laboratory time and efficiently perform laboratory exercises in open labs. In view of teaching features and requirements of Microbiology experiment, we designed and developed ‘Online Student Preparation and Management System of Microbiology Experiment’, which integrated func- tions of student preparation for laboratory sessions and teacher management. In the system each experiment consists of six successive parts, viz., learning objectives, principle, materials and equipments, procedure video, manipulation simulation and online quiz. Teaching practices showed that the application of the system enhanced the preparing quality and makes the management of the experiment teaching more normalized and efficient. It was an effective measure in improving experimental teaching of Microbiology.
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<p><b>OBJECTIVE</b>Study on the flavonoids from the air part of Eupatorium lindleyanum.</p><p><b>METHOD</b>Alcohol percolation, silica gel column chromatography and re-crystallization et al.</p><p><b>RESULT</b>Jaceosidin, kaempferol, quceritin, astragalin, trifolin and hypersoide were isolated from E. lindleyanum. Their structures were elucidated on the basis of spectral evidence.</p><p><b>CONCLUSION</b>Jaceosidin, kaempferol, quceritin, astragalin and trifolin were isolated from E. lindleyanum for the first time.</p>
Subject(s)
Eupatorium , Chemistry , Flavonoids , Chemistry , Kaempferols , Chemistry , Plant Components, Aerial , Chemistry , Plants, Medicinal , Chemistry , Quercetin , ChemistryABSTRACT
<p><b>OBJECTIVE</b>To study the anticancer activity of the extract from Citrus reticulata in vivo.</p><p><b>METHOD</b>Anticancer activities were tested with tumor model in vivo (Sarcoma-180 cells, Heps cells, EAC cells implanted in mice).</p><p><b>RESULT</b>The extract from Citrus reticulata showed marked anticancer activities on Sarcoma-180 cells and Heps cells implanted in mice, had no marked anticancer activities on EAC cells implanted in mice and induced apoptosis of Sarcoma-180 cell.</p><p><b>CONCLUSION</b>The extract from Citrus reticulata will have promising prospects as an anticancer Chinese medicine, but further studies will be needed.</p>
Subject(s)
Animals , Female , Male , Mice , Antineoplastic Agents, Phytogenic , Pharmacology , Apoptosis , Carcinoma, Ehrlich Tumor , Drug Therapy , Pathology , Cell Cycle , Cell Line, Tumor , Citrus , Chemistry , Drugs, Chinese Herbal , Pharmacology , Fruit , Chemistry , Liver Neoplasms, Experimental , Drug Therapy , Pathology , Neoplasm Transplantation , Plants, Medicinal , Chemistry , Sarcoma 180 , Drug Therapy , PathologyABSTRACT
This paper discussed the application of designing experiments from scientific research in Micro-biology courses and its effects on the teachers and students. The problems of the application of designing experiments in Microbiology courses were analyzed. The practice of the teaching reform showed that it give great advantages for the undergraduates with the enhancement of their ability on theory application and sci-entific innovation. This teaching reform could be widely popularized.
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In order to change the situations such as students’passivity and low enthusiasm in the traditional experimental teaching of Microbiology and improve students’comprehensive qualities,exploration and attempt on experimental teaching reforms including teaching contents,teaching modes,laboratory management and evaluation system of examination were done.Teaching practices showed that the normalized ex- periment syllabus based on the correct orientation of experimental teaching of Microbiology,the actualization of teaching mode of basic skill training-integrated experiment-designed experiment and the management of opening laboratory were effective measures in improving experimental teaching of Microbiology.