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71.
During chronic infection, the single celled parasite, Toxoplasma gondii, can migrate to the brain where it has been associated with altered dopamine function and the capacity to modulate host behavior, increasing risk of neurocognitive disorders. Here we explore alterations in dopamine-related behavior in a new mouse model based on stimulant (cocaine)-induced hyperactivity. In combination with cocaine, infection resulted in heightened sensorimotor deficits and impairment in prepulse inhibition response, which are commonly disrupted in neuropsychiatric conditions. To identify molecular pathways in the brain affected by chronic T. gondii infection, we investigated patterns of gene expression. As expected, infection was associated with an enrichment of genes associated with general immune response pathways, that otherwise limits statistical power to identify more informative pathways. To overcome this limitation and focus on pathways of neurological relevance, we developed a novel context enrichment approach that relies on a customized ontology. Applying this approach, we identified genes that exhibited unexpected patterns of expression arising from the combination of cocaine exposure and infection. These include sets of genes which exhibited dampened response to cocaine in infected mice, suggesting a possible mechanism for some observed behaviors and a neuroprotective effect that may be advantageous to parasite persistence. This model offers a powerful new approach to dissect the molecular pathways by which T. gondii infection contributes to neurocognitive disorders.  相似文献   
72.
Medical staff treating Coronavirus Disease 2019 (COVID-19) patients are at high risk for exposure to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), and many have been infected, which may cause panic among medical workers, their relatives, health professionals, and government leaders. We report the epidemiologic and clinical characteristics of healthcare workers and that the majority of infected medical staff had milder symptoms/conditions with a better prognosis than admitted patients. Timely improvement to medical staff’s working conditions such as allowing adequate rest and providing sufficient medical protection is extremely important.  相似文献   
73.
通过克隆海州香薷Actin基因片段并分析其组织表达,为研究海州香薷重金属抗性相关基因的表达调控奠定基础。根据Gen Bank中其他植物Actin基因保守序列设计兼并引物,以海州香薷根总RNA为模板,利用RT-PCR技术分离得到Actin基因片段。序列分析结果表明,海州香薷Actin基因片段长576 bp,编码192个氨基酸,与其他植物同源基因的氨基酸序列相似性为84%-97%,所克隆的序列为Actin基因的同源片段,将其命名为Eh ACT,在Gen Bank中提交序列,获得登录号AGT37260。半定量RT-PCR分析结果表明,Eh ACT在海州香薷的根、茎和叶中表达相对稳定,初步表明其可作为研究海州香薷基因表达的内参基因。  相似文献   
74.
通过过表达手段上调大肿瘤抑制因子1(1arge tumor suppressor gene 1,LATS1)基因在A549细胞中的表达,研究LATS1对A549细胞生长和细胞周期调控的作用。构建过表达LATS1基因的慢病毒载体,转染A549N胞株,采用RT-PCR和蛋白质印迹法检测转染后A549细胞中LATS1、YAPmRNA和蛋白的表达效率;流式细胞术检测细胞凋亡、周期情况:CCK-8检测细胞的增殖水平变化。结果发现,过表达LATS1慢病毒载体转染A549细胞株后,LATS1mRNA及蛋白表达水平高于未处理组及转染空载体组,YAPmRNA及蛋白表达水平低于未处理组及转染空载体组;过表达LATS1慢病毒转染后,A549细胞增殖率从第五天开始低于对照组(P〈0.05),过表达组细胞G1期比例明显增高(P〈0.05),凋亡率明显增加(P〈0.05),差异均有统计学意义。以上结果提示,LATS1可通过下调YAP的表达水平促进A549细胞的凋亡,诱导G1期阻滞,降低细胞的增殖能力。  相似文献   
75.
本实验采用D-氨基半乳糖(D-GalN)诱导的大鼠急性肝损伤模型,观察大鼠肝脏组织化学的变化,探讨肝炎平对急性肝损伤的保护作用。实验分为四组,即正常对照组、模型组、肝炎平及肝得健保护组。结果表明:肝炎平对肝细胞膜系统有一定的保护作用。肝炎平组和肝得健组SDH、CCO及ChE活性明显高于模型组,且与正常对照组相近。本实验模型组ACP的活性明显高于正常组,而肝炎平组ACP的活性明显低于模型组,与正常对照组无显著性差异。提示:肝炎平可显著改善因D-氨基半乳糖所致肝损害的作用。且其对肝细胞的保护作用与肝得健一致。  相似文献   
76.
目的:探讨椎体静脉稀疏区注入骨水泥对骨质疏松椎体压缩性骨折患者行经皮穿刺椎体成形术(percutaneous vertebroplasty,PVP)术中骨水泥渗漏的影响。方法:选择西安交通大学第二附属医院2014年1月至2018年6月收治的61例骨质疏松椎体压缩性骨折患者,根据骨水泥注入区域的不同,将所有患者分为A组(30例)及B组(31例),A组骨水泥注入区域为椎体静脉密集区(椎体中1/3平面处),B组骨水泥注入区域为椎体静脉稀疏区(椎体上1/3及下1/3平面处),对比两组的骨水泥渗漏率,术前、术后6个月时的视觉模拟评分(Visual analogue scale,VAS),治疗中的骨水泥用量、椎体高度恢复率及cobb角恢复度数。结果:B组的骨水泥渗漏率及骨水泥用量均明显低于A组(P0.05)。两组的VAS评分、椎体高度恢复率、cobb角恢复情况对比差异无统计学意义(P0.05)。结论:与椎体静脉密集区相比,在椎体静脉稀疏区注入骨水泥可显著降低骨质疏松椎体压缩性骨折患者PVP术中骨水泥渗漏率,椎体静脉稀疏区可作为PVP术中骨水泥注射的一个相对安全区域。  相似文献   
77.
Physical mapping of the 5S and 45S rDNA in teosintes   总被引:1,自引:0,他引:1  
Han YH  Li LJ  Song YC  Li ZY  Xiong ZY  Li DY 《Hereditas》2002,137(1):16-19
The physical locations of the 5S and 45S rDNA sequences were examined in three types of teosinte, Zea mays ssp. mexicana (2n = 20), Zea diploperennis (2n = 20) and Zea perennis (2n = 40) by biotinylated fluorescence in situ hybridization (FISH). The tested materials only showed one hybridization site of 5S rDNA on their genomes, but they were different in the position of the signals. The hybridization site of Zea mays ssp. mexicana was located on the long arm of chromosome 2, indicating that it is the same as the cultivated maize in the position of 5S rDNA, while the sites of Zea diploperennis and Zea perennis were on the short arms of other chromosomes. For 45S rDNA, one hybridization site was detected at secondary constriction region of the satellite chromosomes in Zea mays ssp. mexicana and Zea diploperennis, while in Zea perennis, besides the site located at the secondary constriction region, a second site on the short arm of another chromosome pair was observed. Our results provide additional evidence for Zea mays ssp. mexicana being a subspecies of Zea mays.  相似文献   
78.
【目的】研究分离自川中丘陵地区大豆根瘤菌的遗传多样性和系统发育。【方法】采用16S rDNA PCR-RFLP和16S rRNA基因、glnII、共生基因(nodC)系统发育分析的方法进行研究。【结果】供试未知菌的16S rDNA用4种限制性内切酶(HaeⅢ、HinfⅠ、MspⅠ及TaqⅠ)酶切后获得5种16S遗传图谱类型。16S rDNA PCR-RFLP结果表明,所有供试菌株在83%水平分为慢生根瘤菌属(Bradyrhizobium)和中华根瘤菌属(Sinonrhizobium)两大类群,而75%的菌株为中华根瘤菌。6个代表菌株的16S rDNA、glnII和nodC三个位点基因的系统发育结果基本一致,4株与S.fredii USDA205T相似度最高;有2株分别与B.yuanmingense CCBAU10071T、B.diazoefficiens USDA110T相似度最高。4个Sinonrhizobium代表菌株16S rDNA、glnII序列相似度分别为98.3%-99.9%、98.2%-100%,但它们的nodC基因序列完全相同。【结论】川中丘陵地区大豆根瘤菌具有较丰富的遗传多样性,S.fredii为优势种。  相似文献   
79.
濒危植物明党参与非濒危种峨参种子休眠和萌发比较   总被引:11,自引:1,他引:11  
研究了濒危植物明党参(Changium smyrnioides)与非濒危种峨参(Anthriscus sylvestris)种子贮存,打破休眠和萌发对水分和温度条件的要求。结果表明,在自然条件下,明党参种子有5个月的休眠期,人工低温(10℃左右)处理40天即可打破休眠;两种植物种子自然温度干燥处理不能打破休眠;两种植物的种子在自然温度变湿层积处理后萌发率最高,萌发持续时间也最长,其中明党参的萌发率地峨参,持续时间短于峨参;自然温度淹水处理大大降低了两种植物种子的萌发率,但明党参仍有7%的萌发率。明党参种子质量和发芽率不应是明党参濒危的直接原因,但因其具有种子产量低,幼苗数量少,存活率高的K-对策,当受到强烈干扰时,种群难以在短期内恢复,容易濒危。  相似文献   
80.
Adoptive cell transfer (ACT) of antigen-specific CD8(+) cytotoxic T lymphocytes (CTLs) is a promising treatment for a variety of malignancies (1). CTLs can recognize malignant cells by interacting tumor antigens with the T cell receptors (TCR), and release cytotoxins as well as cytokines to kill malignant cells. It is known that less-differentiated and central-memory-like (termed highly reactive) CTLs are the optimal population for ACT-based immunotherapy, because these CTLs have a high proliferative potential, are less prone to apoptosis than more differentiated cells and have a higher ability to respond to homeostatic cytokines (2-7). However, due to difficulties in obtaining a high number of such CTLs from patients, there is an urgent need to find a new approach to generate highly reactive Ag-specific CTLs for successful ACT-based therapies. TCR transduction of the self-renewable stem cells for immune reconstitution has a therapeutic potential for the treatment of diseases (8-10). However, the approach to obtain embryonic stem cells (ESCs) from patients is not feasible. Although the use of hematopoietic stem cells (HSCs) for therapeutic purposes has been widely applied in clinic (11-13), HSCs have reduced differentiation and proliferative capacities, and HSCs are difficult to expand in in vitro cell culture (14-16). Recent iPS cell technology and the development of an in vitro system for gene delivery are capable of generating iPS cells from patients without any surgical approach. In addition, like ESCs, iPS cells possess indefinite proliferative capacity in vitro, and have been shown to differentiate into hematopoietic cells. Thus, iPS cells have greater potential to be used in ACT-based immunotherapy compared to ESCs or HSCs. Here, we present methods for the generation of T lymphocytes from iPS cells in vitro, and in vivo programming of antigen-specific CTLs from iPS cells for promoting cancer immune surveillance. Stimulation in vitro with a Notch ligand drives T cell differentiation from iPS cells, and TCR gene transduction results in iPS cells differentiating into antigen-specific T cells in vivo, which prevents tumor growth. Thus, we demonstrate antigen-specific T cell differentiation from iPS cells. Our studies provide a potentially more efficient approach for generating antigen-specific CTLs for ACT-based therapies and facilitate the development of therapeutic strategies for diseases.  相似文献   
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