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981.
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To identify prostate cancer (PCa) patients with a high risk of recurrence is critical before delivering adjuvant treatment. We developed a classifier based on the Enzalutamide treatment resistance‐related genes to assist the currently available staging system in predicting the recurrence‐free survival (RFS) prognosis of PCa patients. We overlapped the DEGs from two datasets to obtain a more convincing Enzalutamide‐resistance‐related‐gene (ERRG) cluster. The five‐ERRG‐based classifier obtained good predictive values in both the training and validation cohorts. The classifier precisely predicted RFS of patients in four cohorts, independent of patient age, pathological tumour stage, Gleason score and PSA levels. The classifier and the clinicopathological factors were combined to construct a nomogram, which had an increased predictive accuracy than that of each variable alone. Besides, we also compared the differences between high‐ and low‐risk subgroups and found their differences were enriched in cancer progression‐related pathways. The five‐ERRG‐based classifier is a practical and reliable predictor, which adds value to the existing staging system for predicting the RFS prognosis of PCa after radical prostatectomy, enabling physicians to make more informed treatment decisions concerning adjuvant therapy.  相似文献   
985.
Alzheimer''s disease (AD) is a neurodegenerative disorder with cognitive impairment and abnormal mental behaviour. There is currently no effective cure. The development of early diagnostic markers and the mining of potential therapeutic targets are one of the important strategies. This study aimed to explore potential biomarkers or therapeutic targets related to AD in the hippocampus and prefrontal cortex, two brain regions highly related to AD. Differentially expressed genes and miRNAs between AD patients and healthy controls were obtained from the Gene Expression Omnibus database. The mRNA‐miRNA network was constructed and key genes involved in AD were screened out by protein–protein interaction analysis, and were subsequently verified by independent datasets and qPCR in an AD mouse model. Our findings showed that six hub genes including CALN1, TRPM7, ATR, SOCS3, MOB3A and OGDH were believed to be involved in the pathogenesis of AD. Western blot analysis further determined that CALN1, ATR and OGDH were the possible biomarkers and therapeutic targets for AD. In addition, 6 possible miRNAs biomarkers have also been verified by qPCR on AD animal models. Our findings may benefit clinical diagnosis and early prevention of AD.  相似文献   
986.
With the advancement in lineage‐specific differentiation from human pluripotent stem cells (hPSCs), downstream cell separation has now become a critical step to produce hPSC‐derived products. Since differentiation procedures usually result in a heterogeneous cell population, cell separation needs to be performed either to enrich the desired cell population or remove the undesired cell population. This article summarizes recent advances in separation processes for hPSC‐derived cells, including the standard separation technologies, such as magnetic‐activated cell sorting, as well as the novel separation strategies, such as those based on adhesion strength and metabolic flux. Specifically, the downstream bioprocessing flow and the identification of surface markers for various cell lineages are discussed. While challenges remain for large‐scale downstream bioprocessing of hPSC‐derived cells, the rational quality‐by‐design approach should be implemented to enhance the understanding of the relationship between process and the product and to ensure the safety of the produced cells.  相似文献   
987.
Due to the overexploitation of farming, as well as habitat destruction, the wild population of Chinese giant salamander (CGS) Andrias davidianus, a species with seven genetically distinct lineages, has decreased by over 80% in the past 70 years. Traditional survey methods have proven to be unsuitable for finding this rare and elusive species. We evaluated the efficacy of environmental DNA (eDNA) sampling to detect CGS indirectly from its aquatic environment. We developed several species-specific primer sets; validated their specificity and sensitivity; and assessed their utility in silico, in the laboratory, and at two field sites harboring released farm-bred CGS. We detected the presence of CGS DNA by using polymerase chain reaction and Sanger sequencing. We also sequenced an amplicon mixture of seven haplotype-represented samples using high-throughput sequencing. Our eDNA methods could detect the presence of CGS at moderate densities reported across its range, proving them as a cost-effective way to establish broad-scale patterns of occupancy for CGS. In addition, our primers enabled the detection of mitochondrial lineage mixture or introduced individuals from geographically isolated populations of CGS.  相似文献   
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989.
何丽红  刘文军  李晶 《生物工程学报》2020,36(10):1961-1969
冠状病毒是一类具有囊膜包裹的线性单股正链RNA病毒,在自然界广泛存在,可引起不同程度的呼吸性传染病。新型冠状病毒是一种新发突发病毒,对各类人群均易感。截止目前,该病已经在世界范围内广泛流行,对公共卫生安全构成极大的威胁。文中从冠状病毒及新型冠状病毒的基因组特征、关键蛋白、对宿主的感染和复制的角度加以综述,旨在为获得病毒侵染宿主细胞致病机制的探究提供理论依据,也为特异的抗病毒药物的研发提供基础支持。  相似文献   
990.
王佳一  邹伟  刘晶 《生物工程学报》2020,36(10):1970-1978
当前新型冠状病毒肆虐,全球确诊患者超过3 500万例,累计死亡患者超过50万例,对于突发疫情,临床尚缺乏有效特异性治疗,新型冠状病毒已成为危害人类健康、社会发展的主要公共卫生问题。间充质干细胞具有抗炎和免疫调节功能,可降低重症患者体内由冠状病毒引发的细胞因子风暴,改善患者肺部纤维化,促进损伤肺组织修复,有望降低新冠肺炎的死亡率。目前已开展多项间充质干细胞治疗新型冠状病毒肺炎临床试验,初步证实了间充质干细胞应用在新冠肺炎方面的安全及有效性。在间充质干细胞治疗新冠肺炎取得进展的同期,还应看到该疗法独有特点及疫情严峻形势对临床试验开和及评价带来的问题与挑战,包括临床试验方案设计、干细胞质量管理以及治疗中的伦理考量。只有对其加以重视,才能保证在严峻疫情下安全有效地开展间充质干细胞治疗新型冠状病毒肺炎的临床试验。  相似文献   
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