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1.
CRISPR/Cas9 has been adapted to disrupt endogenous genes in adoptive T-lymphocyte therapy to prevent graft-versus-host disease. However, genome editing also generates prevalent deleterious structural variations (SVs), including chromosomal translocations and large deletions, raising safety concerns about reinfused T cells. Here, we dynamically monitored the progression of SVs in a mouse model of T-cell receptor (TCR)-transgenic T-cell adoptive transfer, mimicking TCR T therapeutics. Remarkably, CRISPR/Cas9-induced SVs persist and undergo clonal expansion in vivo after three weeks or even two months, evidenced by high enrichment and low junctional diversity of identified SVs post infusion. Specifically, we detected 128 expanded translocations, with 20 615 as the highest number of amplicons. The identified SVs are stochastically selected among different individuals and show an inconspicuous locus preference. Similar to SVs, viral DNA integrations are routinely detected in edited T cells and also undergo clonal expansion. The persistent SVs and viral DNA integrations in the infused T cells may constantly threaten genome integrity, drawing immediate attention to the safety of CRISPR/Cas9-engineered T cells mediated immunotherapy.  相似文献   
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Apolipoprotein AI (apoAI), the major protein component of HDL, is one of the best predictors of coronary artery disease (CAD), with high apoAI and HDL levels being correlated with low occurrences of CAD. The primary function of apoAI is to recruit phospholipid and cholesterol for assembly of HDL particles. Like other exchangeable apolipoproteins, lipid-free apoAI forms a mixture of different oligomers even at 1.0 mg/mL. This self-association property of the exchangeable apolipoproteins is closely associated with the lipoprotein-binding activity of this protein family. It is unclear if the self-association property of apolipoprotein is required for its lipoprotein-binding activity. We developed a novel method for engineering an oligomeric protein to a monomeric, biologically active protein. Using this method, we generated a monomeric mouse apoAI mutant that is active. This mutant contains the first 216 residues of mouse apoAI and replaces six hydrophobic residues with either polar or smaller hydrophobic residues at the defined positions (V118A/A119S/L121Q/T191S/T195S/T199S). Cross-linking results show that this mutant is greater than 90% monomeric at 8 mg/mL. CD, DSC, and NMR results indicate that the mutant maintains an identical secondary, tertiary structure and stability as those of the wild-type mouse apoAI. Lipid-binding assays suggest that the mutant shares an equal lipoprotein-binding activity as that of the wild-type apoAI. In addition, both the monomeric mutant and the wild-type protein make nearly identical rHDL particles. With this monomeric mouse apoAI, high-quality NMR data has been collected, allowing for the NMR structural determination of lipid-free apoAI. On the basis of these results, we conclude that this apoAI mutant is a monomeric, active apoAI useful for structural determination.  相似文献   
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Niu  Lili  Guo  Yanchen  Lin  Zhengrong  Shi  Zhe  Bian  Tianyuan  Qi  Lin  Meng  Long  Grace  Anthony A.  Zheng  Hairong  Yuan  Ti-Fei 《中国科学:生命科学英文版》2020,63(9):1328-1336
Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.  相似文献   
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为了解云南省急性弛缓性麻痹(Acute flaccid paralysis,AFP)病例中柯萨奇病毒B组5型(Coxsackievirus B5,CV-B5)感染情况及病毒基因特征,采用回顾性研究的方法,收集AFP监测系数据资料,描述CV-B5感染AFP病例的流行病学特征及临床表现;对CV-B5分离株进行完整VP1区逆转录-聚合酶链反应扩增和核苷酸序列测定,测序结果进行同源性分析和系统发生学研究.结果显示,15例CV-B5阳性的AFP病例散在分布于7个云南省内州市、贵州省及缅甸;男女比例为1∶2,5岁以下儿童占73.3%,53.3%(8/15)的病例麻痹时伴发热,以双侧下肢麻痹(66.7%,10/15)为主,临床诊断多为肌炎(33.3%,5/15),1例病例残留麻痹.CV-B5云南株之间以及与原型株之间的核苷酸同源性分别为75.0%~100.0%和77.2%~82.0%.云南本地存在两个基因型的CV-B5共循环,大多数云南株(16株)与中国大陆CV-B5分离株均属于D基因型(D3亚型),另外两株云南株属于国外优势流行的C基因型,与其他云南株之间存在较大的核苷酸差异(20.4%~25.0%).本研究描述了 CV-B5云南地方株的分子流行病学特征,首次发现我国存在C基因型.研究显示分离自不同疾病来源及健康人群的CV-B5在亲缘关系树上无特异性区分.  相似文献   
6.
Gastric cancer is one of the top causes of cancer-related death around the world, and poor prognosis of gastric cancer is due to the lack of early detection and effective treatment especially in male. Here, we first revealed the role of histone lysine-specific demethylase 5D (KDM5D) in gastric cancer in male. KDM5D was associated with the metastasis of gastric cancer because of its critical role in the epithelial-mesenchymal transition of gastric cancer cells. Downregulation of KDM5D in gastric cancer cells significantly increase the number of migrated or invaded cells due to the increasing expressions of mesenchymal markers. Downregulation of KDM5D also promotes tumor formation of gastric cancer cell in vivo. For mechanism, downregulation of KDM5D could inhibit the demethylation in the promoter of CUL4A, which lead to the increasing expression of ZEB1 and decreasing expressions of p21 and p53. Collectively, KDM5D performed its role in metastasis of gastric cancer through demethylation in the promoter of CUL4A, and it suggested us a novel target in gastric cancer treatment in male.  相似文献   
7.
G-protein-coupled receptor 41 (GPR41) and G-protein-coupled receptor 43 (GPR43) are important short-chain fatty acids (SCFAs) receptors. Previous studies indicated that GPR41 and GPR43 are involved in the secretion of gastrointestinal peptides, and glucose and lipid metabolism, and are closely related to obesity and type II diabetes, and other diseases. The purpose of the study was to explore the relationship of the GPR41 and GPR43 with seasonal breeding, and provide new prospects for further exploring the nutritional needs of breeding. We identified the localization and expression levels of GPR41 and GPR43 in the colon of the wild ground squirrels (Spermophilus dauricus) both in the breeding season and non-breeding season. The histological results revealed that the lumen diameter of the colon had obvious seasonal changes, and the diameter of the colonic lumen in the non-breeding season was larger than that in the breeding season. Immunohistochemical staining suggested that GPR41 and GPR43 are expressed in the simple layer columnar epithelium. In addition, compared with the breeding season, the mRNA and protein expression levels of GPR41 and GPR43 in the colon were higher during the non-breeding season. In general, these results indicated that GPR41 and GPR43 might play a certain role in regulating seasonal breeding.Key words: GPR41, GPR43, colon, wild ground squirrel, seasonal breeding  相似文献   
8.
Prostate cancer is the most common non-skin cancer and the second leading cause of cancer related mortality for men in the United States. There is strong empirical and epidemiological evidence supporting a stronger role of genetics in early-onset prostate cancer. We performed a genome-wide association scan for early-onset prostate cancer. Novel aspects of this study include the focus on early-onset disease (defined as men with prostate cancer diagnosed before age 56 years) and use of publically available control genotype data from previous genome-wide association studies. We found genome-wide significant (p<5×10−8) evidence for variants at 8q24 and 11p15 and strong supportive evidence for a number of previously reported loci. We found little evidence for individual or systematic inflated association findings resulting from using public controls, demonstrating the utility of using public control data in large-scale genetic association studies of common variants. Taken together, these results demonstrate the importance of established common genetic variants for early-onset prostate cancer and the power of including early-onset prostate cancer cases in genetic association studies.  相似文献   
9.
Pi R  Mao X  Chao X  Cheng Z  Liu M  Duan X  Ye M  Chen X  Mei Z  Liu P  Li W  Han Y 《PloS one》2012,7(2):e31921
We have previously synthesized a series of hybrid compounds by linking ferulic acid to tacrine as multifunctional agents based on the hypotheses that Alzheimer's disease (AD) generates cholinergic deficiency and oxidative stress. Interestingly, we found that they may have potential pharmacological activities for treating AD. Here we report for the first time that tacrine-6-ferulic acid (T6FA), one of these compounds, can prevent amyloid-β peptide (Aβ)-induced AD-associated pathological changes in vitro and in vivo. Our results showed that T6FA significantly inhibited auto- and acetylcholinesterase (AChE)-induced aggregation of Aβ(1-40)in vitro and blocked the cell death induced by Aβ(1-40) in PC12 cells. In an AD mouse model by the intracerebroventricular injection of Aβ(1-40), T6FA significantly improved the cognitive ability along with increasing choline acetyltransferase and superoxide dismutase activity, decreasing AChE activity and malondialdehyde level. Based on our findings, we conclude that T6FA may be a promising multifunctional drug candidate for AD.  相似文献   
10.
Zeng X  Yuan Z  Tong X  Li Q  Gao W  Qin M  Liu Z 《Molecular biology reports》2012,39(5):5737-5744
Oryzoideae (Poaceae) plants have economic and ecological value. However, the phylogenetic position of some plants is not clear, such as Hygroryza aristata (Retz.) Nees. and Porteresia coarctata (Roxb.) Tateoka (syn. Oryza coarctata). Comprehensive molecular phylogenetic studies have been carried out on many genera in the Poaceae. The different DNA sequences, including nuclear and chloroplast sequences, had been extensively employed to determine relationships at both higher and lower taxonomic levels in the Poaceae. Chloroplast DNA ndhF gene and atpB-rbcL spacer were used to construct phylogenetic trees and estimate the divergence time of Oryzoideae, Bambusoideae, Panicoideae, Pooideae and so on. Complete sequences of atpB-rbcL and ndhF were generated for 17 species representing six species of the Oryzoideae and related subfamilies. Nicotiana tabacum L. was the outgroup species. The two DNA datasets were analyzed, using Maximum Parsimony and Bayesian analysis methods. The molecular phylogeny revealed that H. aristata (Retz.) Nees was the sister to Chikusichloa aquatica Koidz. Moreover, P. coarctata (Roxb.) Tateoka was in the genus Oryza. Furthermore, the result of evolution analysis, which based on the ndhF marker, indicated that the time of origin of Oryzoideae might be 31 million years ago.  相似文献   
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