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61.
Shixing Yang Yumin He Ju Zhang Dianqi Zhang Yan Wang Xiang Lu Xiaochun Wang Quan Shen Likai Ji Hongyan Lu Wen Zhang 《中国病毒学》2022,37(1):82-93
Diarrhea is the third leading cause of death in developing countries in children under the age of five. About half a million children die of diarrhea every year, most of which in developing countries. Viruses are the main pathogen of diarrhea. In China, the fecal virome of children with diarrhea has been rarely studied. Using an unbiased viral metagenomics approach, we analyzed the fecal virome in children with diarrhea. Many DNA or RNA viruses associated with diarrhea identified in those fecal samples were mainly from six families of Adenoviridae, Astroviridae, Caliciviridae, Parvoviridae, Picornaviridae, and Reoviridae. Among them, the family of Caliciviridae accounts for the largest proportion of 78.42%, following with Adenoviridae (8.94%) and Picornaviridae (8.36%). In addition to those diarrhea-related viruses that have already been confirmed to cause human diarrhea, the viruses not associated with diarrhea were also identified including anellovirus and picobirnavirus. This study increased our understanding of diarrheic children fecal virome and provided valuable information for the prevention and treatment of viral diarrhea in this area. 相似文献
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Cloned zebrafish by nuclear transfer from long-term-cultured cells 总被引:10,自引:0,他引:10
Although mammals have been cloned from genetically manipulated cultured cells, a comparable achievement has not been realized in lower vertebrates. Here we report that fertile transgenic zebrafish can be obtained by nuclear transfer using embryonic fibroblast cells from long-term cultures. The donor nuclei, modified by retroviral insertions expressing green fluorescent protein (GFP), were transplanted into manually enucleated eggs. Overall, a 2% success rate was achieved, resulting in 11 adult transgenic zebrafish expressing GFP. These nuclear transplants produced fertile, diploid offspring, and their F1/F2 progeny continued to express GFP in a pattern identical to that of the founder fish. This finding demonstrates that slowly dividing nuclei from cultured cells can be reprogrammed to support rapid embryonic development and sets up a foundation for targeted genetic manipulation in zebrafish. 相似文献
65.
选取23种香型水稻品种为供试材料,利用分子标记检测方法,进行了10个与稻米食味品质相关基因:耽、SSII-3、SBE3、AGPiso、SSIII-2、AGPlar、P比、SSI、ISA、SSIV-2的基因型分析。结果发现,含有最好食味品质基因型的水稻是“2845”;其次是“松香早粳”、“苏沪香粳”、“B1”、“武运2645”、“通运粳”、“银香28”、“香粳49②”、“99983”、“W香99075”、“07-08”、“云粳优15”、“29185”、“南海318”:另外9种香稻,“大华香粳”、“武香14”、“香粳”、“Della光身稻”、“大粒香”、“泰国香稻”、“C香517”、“香稻1号”、“中香1号”都分别含有一些可能会影响稻米食味品质的基因型。开展本研究不仅能够使人们对这些香稻食味品质基因型有一个全面的认识,还可为今后利用分子标记辅助培育优良食味品质香稻新品种和亲本的选择提供重要的基因型信息。 相似文献
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随着细胞与组织工程的迅猛发展,能够促进细胞黏附、生长和分化的生物材料基质支架的研究日益重要。具有生物相容性且含水量超过99%的自组装肽水凝胶因其很好地符合理想的生物材料基质支架标准而备受重视。这类自我互补的两亲寡肽含50%的带电残基,并且以交替的离子亲水性和不带电的氨基酸残基周期性重复为特征;在其寡肽的氨基末端可用直接固相合成法修饰几个短序列生物活性模体进行功能化,用以促进不同细胞的黏附生长和靶向定位。现对自组装肽水凝胶的结构特征、自组装机制、对细胞黏附生长的影响以及未来自组装肽生物材料设计的目标进行综述. 相似文献
68.
The endoplasmic reticulum (ER) plays essential roles indispensable for cellular activity and survival, including functions such as protein synthesis, secretory and membrane protein folding, and Ca2+ release in cells. The ER is sensitive to stresses that can lead to the aggregation and accumulation of misfolded proteins, which eventually triggers cellular dysfunction; severe or prolonged ER stress eventually induces apoptosis. ER stress-induced apoptosis causes several devastating diseases such as atherosclerosis, neurodegenerative diseases, and diabetes. In addition, the production of biopharmaceuticals such as monoclonal antibodies requires the maintenance of normal ER functions to achieve and maintain the production of high-quality products in good quantities. Therefore, it is necessary to develop methods to efficiently relieve ER stress and protect cells from ER stress-induced apoptosis. The silkworm storage protein 1 (SP1) has anti-apoptotic activities that inhibit the intrinsic mitochondrial apoptotic pathway. However, the role of SP1 in controlling ER stress and ER stress-induced apoptosis has not been investigated. In this paper, we demonstrate that SP1 can inhibit apoptosis induced by a well-known ER stress inducer, thapsigargin, by alleviating the decrease in cell viability and mitochondrial membrane potential. Interestingly, SP1 significantly blocked increases in CHOP and GRP78 expression as well as ER Ca2+ leakage into the cytosol following ER stress induction. This indicates that SP1 protects cells from ER stressinduced apoptosis by functioning as an upstream inhibitor of apoptosis. Therefore, studying SP1 function can offer new insights into protecting cells against ER stress-induced apoptosis for future applications in the biopharmaceutical and medicine industries. 相似文献
69.
通过PCR技术从粘质沙雷氏菌H3010基因组DNA中扩增出该D-乳酸脱氢酶基因,连接至pET-28a(+)表达载体,转入大肠杆菌BL21(DE3)中进行了重组表达,优化了酶纯化的条件,并对其酶学性质进行初步研究。结果表明,获得的该酶编码基因全长993bp,编码330个氨基酸,大小为37kDa。经优化表达及纯化条件后重组酶纯度可达90%。酶学性质研究发现,该重组酶最适反应温度为60℃,最适酶促反应pH为7.5(O.2mol/L磷酸盐缓冲液),37℃下测得对底物丙酮酸的动力学参数Km=3.39mmol/L,Vmax=6.87mmol/(mg·min),对辅酶NADH的动力学参数Km=1.43mmol/L,Vmax=1.61mmo]/(mg·min)。为酶法生产D-乳酸及利用代谢工程构建产D-乳酸的基因工程菌打下基础。 相似文献
70.
O. I. Kiselev V. M. Blinov M. M. Pisareva V. A. Ternovoy A. P. Agafonov D. V. Saraev M. Ju. Eropkin T. G. Lobova V. A. Grigorieva M. P. Grudinin 《Molecular Biology》2008,42(1):70-78
In the second half of 2005, a large-scale outbreak of influenza in poultry and wild birds was caused by a highly pathogenic H5N1 influenza virus in Russia. The level of pathogenicity is a polygenic trait, and most individual genes contribute to the influenza A virus pathogenicity in birds, animals, and humans. The full-length nucleotide sequences were determined for H5N1 strains isolated in the Kurgan region (Western Siberia). The structure of viral proteins was analyzed using the deduced amino acid sequences. The receptor-binding site of hemagglutinin (HA) in strains A/chicken/Kurgan/05/2005 and A/duck/Kurgan/08/2005 was typical for avian influenza viruses and contained Glu and Gly at positions 226 and 228, respectively. The structure of the basic amino acid cluster located within the HA cleavage site was identical in all isolates: QGERRRKKR. According to the neuraminidase structure, all H5N1 isolates from the Kurgan region were assigned to the Z genotype. Amino acid residues typical for the avian influenza virus were revealed in 30 out of 32 positions of M1, M2, NP, PA, and PB2, determining the host range specificity. One of the strains contained Lys at position 627 of PB2. Isolates from the Kurgan region were shown to have a remantadine-sensitive genotype. Both strains contained Glu at position 92 of NS1, indicating that the virus is interferon-resistant. Phylogenetic analysis related the Kurgan isolates to subclade 2 of clade 2 of highly pathogenic H5N1 influenza viruses. 相似文献