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31.
Huan Cai Yu Jiang Sheng Zhang Ning-Ning Cai Wen-Qian Zhu Rui Yang Bo Tang Zi-Yi Li Xue-Ming Zhang 《Andrologia》2021,53(6):e14056
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm. 相似文献
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Miguel Relvas Ana Beco Luciano Pereira Ana Oliveira Jos Silvano Rui Silva Nídia Marques Lurdes Santos Luís Coentro Manuel Pestana 《Seminars in dialysis》2021,34(1):83-88
In peritoneal dialysis (PD), a cloudy dialysate is an alarming finding. Bacterial peritonitis is the most common cause, however, atypical infections and non‐infectious causes must be considered. A 46‐year‐old man presented with asthenia, paraesthesia, foamy urine and hypertension. Laboratory testing revealed severe azotaemia, anaemia, hyperkalaemia and nephrotic‐range proteinuria. Haemodialysis was started through a central venous catheter. Later, due to patient preference, a Tenckhoff catheter was inserted. Conversion to PD occurred 3 weeks later, during hospitalization for a presumed central line infection. A month later, the patient was hospitalized for neutropenic fever. He was diagnosed an acute parvovirus infection and was discharged under isoniazid for latent tuberculosis. Four months later, the patient presented with fever and a cloudy effluent. Peritoneal fluid (PF) cytology was suggestive of infectious peritonitis, but the symptoms persisted despite antibiotic therapy. Bacterial and mycological cultures were negative. No neoplastic cells were detected. Mycobacterium tuberculosis eventually grew in PF cultures, despite previous negative molecular tests. Directed therapy was then initiated with excellent response. Thus, facing a cloudy effluent, one must consider multiple aetiologies. Diagnosis of peritoneal tuberculosis is hampered by the lack of highly sensitive and specific exams. Here, diagnosis was only possible due to positive mycobacterial cultures. 相似文献
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Yu Hongjuan Zeng Xueyun Sui Mingjie Liu Rui Tan Rachel Lee-Yin Yang Jinjin Huang Weidong Luo Nan 《Quality of life research》2021,30(3):855-866
Quality of Life Research - This study aimed to compare the measurement properties of EQ-5D-3L(3L) and EQ-5D-5L(5L) in patients with acute myeloid leukemia (AML) in China. We consecutively recruited... 相似文献
36.
RNA silencing: a conserved antiviral immunity of plants and animals 总被引:19,自引:0,他引:19
RNA silencing is a novel RNA-guided gene regulatory mechanism operational in a wide range of eukaryotic organisms from fission yeast, plants, to mammals. This article reviews the recent progress on aspects of RNA silencing that are related to its biological function as a conserved antiviral immunity of plants and animals, and highlights features of this novel antiviral response in invertebrate animals as compared to the known innate and adaptive immunities. Finally, we discuss evidence that suggests a natural antiviral role for RNA silencing in vertebrates as well as experimental approaches that may facilitate the identification of first mammalian viral suppressors of RNA silencing. 相似文献
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目的 分析临床急性感染性疾病所致肝功能损害的特点及其恢复时间。方法 对 135例急性感染性疾病患者入院肝功能指标进行分析 ,观察治疗第 2周及第 4周时患者异常肝功能指标恢复情况。结果 除 6例死亡外 ,其余患者异常肝功能指标升高多在正常值上限 3倍以内 ,治疗第 4周异常肝功能指标治愈率分别为 AL T92 .4%、AST91.6 %、GGT75 .6 %、AL P91.3%、 SB10 0 %、 SB’ 10 0 %和 TBA 85 .7% ,HBs Ag ( )携带者与 HBs Ag (- )者治疗第 4周上述指标治愈率无显著差异。第 4周时 GGT仍升高者恢复缓慢或不易恢复正常。结论 急性感染性疾病致肝功能损害多呈轻度及一过性升高 ;HBs Ag ( )携带者肝脏应急储备及修复功能较正常人无明显下降 ;GGT恢复缓慢或不易恢复正常者可能留有持久性的肝内毛细胆管损伤 相似文献
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