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Nighat Perveen Sabir Bin Muzaffar Mohammad Ali Al-Deeb 《Saudi Journal of Biological Sciences》2021,28(2):1417-1425
The novel coronavirus disease (COVID-19) that emerged in December 2019 had caused substantial morbidity and mortality at the global level within few months. It affected economies, stopped travel, and isolated individuals and populations around the world. Wildlife, especially bats, serve as reservoirs of coronaviruses from which the variant Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) emerged that causes COVID-19. In this review, we describe the current knowledge on COVID-19 and the significance of wildlife hosts in its emergence. Mammalian and avian coronaviruses have diverse host ranges with distinct lineages of coronaviruses. Recombination and reassortments occur more frequently in mixed-animal markets where diverse viral genotypes intermingle. Human coronaviruses have evolved through gene gains and losses primarily in interfaces where wildlife and humans come in frequent contact. There is a gap in our understanding of bats as reservoirs of coronaviruses and there is a misconception that bats periodically transmit coronaviruses to humans. Future research should investigate bat viral diversity and loads at interfaces between humans and bats. Furthermore, there is an urgent need to evaluate viral strains circulating in mixed animal markets, where the coronaviruses circulated before becoming adapted to humans. We propose and discuss a management intervention plan for COVID-19 and raise questions on the suitability of current containment plans. We anticipate that more virulent coronaviruses could emerge unless proper measures are taken to limit interactions between diverse wildlife and humans in wild animal markets. 相似文献
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The association of the FTO gene with obesity has been implicated in various human populations. The FTO gene is also most likely involved in the regulation of energy balance and feed intake. Here, the FTO gene was studied as a candidate gene for fatness and growth rate traits in pigs. The amino acid sequence of the FTO gene showed high conservation among human, pig, and other important domestic animals. Twelve variants including ten SNPs and two indels were detected, and then five SNPs within different genomic regions were genotyped in the ISU Berkshire × Yorkshire pig resource family. The linkage disequilibrium analyses revealed that most of these FTO variants were not in strong LD with each other. The SNPs c.46–139A > T within intron 1 and a synonymous mutation c.594C > G (Ala198Ala) within exon 3 had significant (P < 0.01) associations with average daily gain on test and total lipid percentage in muscle, respectively. Five major haplotypes were identified and the subsequent association analyses suggested that haplotype 2 (-CTTGG-) was the most favorable for increased growth rate, while haplotype 1 (-CTACG-) was unfavorably associated with intramuscular fatness traits. 相似文献
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目的:探讨658 nm低能量激光照射对人牙周膜细胞增殖、碱性磷酸酶活性及纤维连接蛋白合成的影响.方法:改良组织块法体外培养人牙周膜细胞.通过658 nm激光照射人牙周膜细胞,观察能量密度为1.86 J/cm2和3.72 J/cm2激光照射后不同时间点细胞增殖效应、碱性磷酸酶活性和纤维连接蛋白的变化.结果:1.86 J/cm2和3.72 J/cm2能量密度的激光照射人牙周膜细胞,可显著促进细胞增殖效应.3.72 J/cm2能量密度的激光照射可提高人牙周膜细胞碱性磷酸酶活性;能量密度为1.86 J/cm2的激光照射人牙周膜细胞72 h后,细胞中纤维连接蛋白分泌量增加.结论:658 nm低剂量激光照射可促进人牙周膜细胞增殖;适量的低剂量激光照射人牙周膜细胞可促进其碱性磷酸酶活性及纤维连接蛋白的分泌. 相似文献
158.
Guohua Feng Ji-Yuan Zhang Qing-Lei Zeng Lei Jin Junliang Fu Bin Yang Ying Sun Tianjun Jiang Xiangsheng Xu Zheng Zhang Jinhong Yuan Liyuan Wu Fu-Sheng Wang 《Molecules and cells》2013,36(4):362-367
Interleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms. The study subjects included nineteen CHC patients who were grouped by viral load (low, < 106 RNA copies/ml, n = 8; high, > 106 RNA copies/ml, n = 11). The peripheral frequency of HCV-specific IL-21+CD4+ T cells was higher in the low viral load group and was negatively correlated with the serum HCV RNA viral load in all CHC patients. Meanwhile, IL-21+ cells accumulated in the liver in the low viral load group. In vitro, IL-21 treatment increased the expression of proliferation markers and cytolytic molecules on HCV-specific CD8+ T cells. In summary, these findings suggest that HCV-specific IL-21+CD4+ T cells might contribute to HCV control by rescuing HCV-specific CD8+ T cells in CHC patients. 相似文献
159.
Michael Sandberg Long Bin Tan Heow Pueh Lee 《Computer methods in biomechanics and biomedical engineering》2013,16(12):684-692
AbstractIn the present study, the free fall impact test in accordance with the EN1078 standard for certification of bicycle helmets is replicated using numerical simulations. The impact scenario is simulated using an experimentally validated, patient-specific head model equipped with and without a bicycle helmet. Head accelerations and intracranial biomechanical injury metrics during the impacts are recorded. It is demonstrated that wearing the bicycle helmet during the impact reduces biomechanical injury metrics, with the biggest reduction seen in the metric for skull fracture. 相似文献
160.