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93.
Dan Li Yinguang Liu Xiaolan Qi Yuan Wen Pan Li Zhao Ma Yongjie Liu Haixue Zheng Zhijie Liu 《中国病毒学》2021,36(2):187-195
African swine fever virus(ASFV) is the etiological agent of African swine fever(ASF), an often lethal disease in domestic and wild pigs. ASF represents a major threat to the swine industry worldwide. Currently, no commercial vaccine is available because of the complexity of ASFV or biosecurity concerns. Live attenuated viruses that are naturally isolated or genetically manipulated have demonstrated reliable protection against homologous ASFV strain challenge. In the present study, a mutant ASFV strain with the deletion of ASFV MGF-110-9 L(ASFV-D9 L) was generated from a highly virulent ASFV CN/GS/2018 parental strain, a genotype II ASFV. Relative to the parental ASFV isolate, deletion of the MGF-110-9 L gene significantly decreased the ability of ASFV-D9 L to replicate in vitro in primary swine macrophage cell cultures. The majority of animals inoculated intramuscularly with a low dose of ASFV-D9 L(10 HAD50) remained clinically normal during the 21-day observational period. Three of five ASFV-D9 L-infected animals displayed low viremia titers and low virus shedding and developed a strong virus-specific antibody response, indicating partial attenuation of the ASFV-D9 L strain in pigs. The findings imply the potential usefulness of the ASFV-D9 L strain for further development of ASF control measures. 相似文献
94.
Sheng Chen Xinheng Zhang Yu Nie Hongxin Li Weiguo Chen Wencheng Lin Feng Chen Qingmei Xie 《中国病毒学》2021,36(2):196-206
African swine fever virus(ASFV), as a member of the large DNA viruses, may regulate autophagy and apoptosis by inhibiting programmed cell death. However, the function of ASFV proteins has not been fully elucidated, especially the role of autophagy in ASFV infection. One of three Pyrroline-5-carboxylate reductases(PYCR), is primarily involved in conversion of glutamate to proline. Previous studies have shown that depletion of PYCR2 was related to the induction of autophagy. In the present study, we found for the first time that ASFV E199 L protein induced a complete autophagy process in Vero and HEK-293 T cells. Through co-immunoprecipitation coupled with mass spectrometry(CoIP-MS)analysis, we firstly identified that E199 L interact with PYCR2 in vitro. Importantly, our work provides evidence that E199 L down-regulated the expression of PYCR2, resulting in autophagy activation. Overall, our results demonstrate that ASFV E199 L protein induces complete autophagy through interaction with PYCR2 and down-regulate the expression level of PYCR2, which provide a valuable reference for the role of autophagy during ASFV infection and contribute to the functional clues of PYCR2. 相似文献
95.
《遗传学报》2021,48(12):1104-1110
Identification of carriers of fragile X syndrome (FXS) with the subsequent prenatal diagnosis and knowledge of FXS-associated genetic profiles are essential for intervention in specific populations. We report the results of carrier screening of 39,458 East Asian adult women and prenatal diagnosis from 87 FXS carriers. The prevalence of FXS carriers and full mutation fetuses was estimated to be 1/581 and 1/3124 in East Asian populations, respectively. We confirmed the validity of the current threshold of CGG trinucleotide repeats for FMR1 categorization; the integral risks of full mutation expansion were approximately 6.0%, 43.8%, and 100% for premutation alleles with 55–74, 75–89, and ≥ 90 CGG repeats, respectively. The protective effect of AGG (adenine-guanine-guanine nucleotides) interruption in East Asian populations was validated, which is important in protecting premutation alleles with 75–89 CGG repeats from full mutation expansion. Finally, family history was shown not an effective indicator for FXS carrier screening in East Asian populations, and population-based screening was more cost-effective. This study provides an insight into the largest carrier screening and prenatal diagnosis for FXS in East Asian populations to date. The FXS-associated genetic profiles of East Asian populations are delineated, and population-based carrier screening is shown to be promising for FXS intervention. 相似文献
96.
《遗传学报》2021,48(10):899-907
Southern East Asia, including Guangxi and Fujian provinces in China, is home to diverse ethnic groups, languages, and cultures. Previous studies suggest a high complexity regarding population dynamics and the history of southern East Asians. However, large-scale genetic studies on ancient populations in this region are hindered by limited sample preservation. Here, using highly efficient DNA capture techniques, we obtain 48 complete mitochondrial genomes of individuals from Guangxi and Fujian in China and reconstruct their maternal genetic history over the past 12,000 years. We find a strong connection between southern East Asians dating to ~12,000–6000 years ago and present-day Southeast Asians. In addition, stronger genetic affinities to northern East Asians are observed in historical southern East Asians than Neolithic southern East Asians, suggesting increased interactions between northern and southern East Asians over time. Overall, we reveal dynamic connections between ancient southern East Asians and populations located in surrounding regions, as well as a shift in maternal genetic structure within the populations over time. 相似文献
97.
Haider Karar Muhammad Amjad Bashir Abdul Basit Sagheer Atta Ahmad Ali Anjum Ali Bakhsh Arif Hussain Abid Hameed Yong Wang Reem Atalla Alajmi Dina M. Metwally Muhammad Imran 《Saudi Journal of Biological Sciences》2021,28(4):2366-2373
A study was performed to assess the preference of fourteen mango cultivars for fruit flies and their management by bagging. So the choice of Tephritid flies to mango cultivars during fruiting phase is crucial. Fourteen different cultivars of mango viz., ‘Dusehri’, ‘Malda’, ‘Langra’ early cultivars, ‘Chaunsa’, ‘Fajri Klan’, ‘Sensation’ medium whereas ‘Sanglakhi’, ‘Retaul-12’, ‘Mehmood Khan’, ‘Tukhmi’, ‘Kala Chaunsa’, ‘Chitta Chaunsa’, ‘Dai Wala’ and ‘Sobey De Ting’ late cultivars were assessed for their suitability for fruit flies. The results indicate that the population density of fruit flies was higher on late cultivars like ‘Sanglakhi’ (20.61 percent), ‘Mehmood Khan’ (20.22 percent) and ‘Reutal-12’ (19.92 percent) were proved to be highly susceptible to fruit flies. Among these the cultivar ‘Reutal-12’ was selected being commercial and future cultivar for the management of fruit flies through bagging. The results reported that the attack of tephritid fruit flies and other insect pests were zero in bagged fruits as compared with control. It was further recorded that the bagged fruits has maximum average fruit weight i.e. 203.50 and 197.83 g per fruit was noted in those treatments where butter paper bag and brown paper bag was wrapped with better coloration as compared with un-bagged fruit with 159.5 g per fruit. Similarly, on an average fruit length were more i.e. 90.17, 91.33 mm in bagged fruit and 85.33 in un-bagged fruits. Furthermore, bagged fruits have zero incidence of disease with reduced fruit crack, fruit sunburn, mechanical damage, bird damage, fruit blemished and agrochemical residues on the fruit. So, it is concluded that the special attention should be given on ‘Reutal-12’ for the management of fruit flies when devising an IPM program for the control of fruit flies. Further, bagging has proved to be the good agricultural practices for the production of quality mango. 相似文献
98.
我国高度重视野生动物保护事业, 认真履行野生动物保护国际义务, 积极鼓励公众参与, 以扩大野生动物保护事业的公众基础。已有文献多关注了公众的国内野生动物保护意愿, 鲜有文献关注公众对国际野生动物的保护意愿, 难以为促进公众参与国际野生动物保护事业提供决策参考。本研究以全球旗舰物种非洲象(Loxodonta africana)为例, 结合非洲象保护的相关研究与实践, 构建拓展的计划行为理论框架, 通过线下和线上调研获取数据, 运用结构方程模型, 从态度、规范、知觉行为控制、过去经验及个体特征五个方面, 分析了我国公众的非洲象保护意愿及影响因素。结果表明: (1) 68.5%的公众具有非洲象保护愿意; (2)公众规范(系数为0.422)、过去经验(系数为0.253)、知觉行为控制(系数为0.160)、保护态度(系数为0.156)对保护意愿存在显著的正向影响; 男性公众(系数为-0.054)的保护意愿低于女性公众; 居住在西部地区的公众(系数为0.066)保护意愿更高; (3)模型整体通过了拟合检验, 表明研究结果具有稳健性。本研究的政策建议如下: (1)明确政策导向作用, 提升公众的道德义务感和社会责任感; (2)加强宣传教育, 丰富公众知识经验, 培育公众积极的保护态度; (3)拓宽保护参与渠道, 提高公众知觉行为控制; (4)制定合理方案, 提升保护宣教等实践活动成效。 相似文献
99.
《Journal of Asia》2021,24(4):1070-1076
Three species of the snakefly genus Inocellia Schneider, 1843 (Raphidioptera: Inocelliidae) are reported from the Hengduan Mountains in southwestern China. Among them, Inocellia yulongensis sp. nov. is described as new to science. Inocellia cheni Liu, H. Aspöck, Yang & U. Aspöck, 2010 is first recorded from Sichuan Province based on a newly collected male from a locality over 4200 m a.s.l. Inocellia obtusangularis Liu, H. Aspöck, Yang & U. Aspöck, 2010 is first recorded from Yunnan Province. The rich species diversity of snakeflies and its biogeographic significance from the Hengduan Mountains are discussed. 相似文献
100.
Lukáš Pola Vojtěch Hejduk Aleš Zíka Tomáš Winkelhöfer Jiří Šmíd Salvador Carranza Mohammed Shobrak Mohammad Abu Baker Zuhair Sami Amr 《Saudi Journal of Biological Sciences》2021,28(6):3511-3516
Geckos of the genus Trigonodactylus are widely distributed in the sand deserts of the Arabian Peninsula. Three species of this genus are currently recognized, with a fourth one, Stenodactylus pulcher, which placement within Trigonodactylus has been tentatively suggested, but not yet confirmed. We present a phylogenetic analysis of the genus Trigonodactylus with new specimens collected in central Saudi Arabia and southern Jordan. New genetic data has been generated from three mitochondrial markers to investigate the phylogenetic relationships of all species of the genus and to assess the putative generic assignment of S. pulcher. Our results confirm that S. pulcher indeed belongs within Trigonodactylus, branching as a sister lineage to all other species of the genus. The new samples cluster within Trigonodactylus arabicus, thus confirming the genetic homogeneity of the species across its large and seemingly inhospitable range. The new specimen collected in southern Jordan represents the first record for the country and a considerable range extension to the northwest from all previously reported localities. Our findings and discovery of a new species for Jordan highlight the need of more field surveys to be carried out in the underexplored parts of Jordan and northern Saudi Arabia, as these places still hold a potential for new discoveries and are crucial for understating the biogeography of the Arabian herpetofauna. 相似文献