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排序方式: 共有1658条查询结果,搜索用时 15 毫秒
81.
Florian Villegas Daphné Lehalle Daniela Mayer Melanie Rittirsch Michael B. Stadler Marietta Zinner Daniel Olivieri Pierre Vabres Laurence Duplomb-Jego Eveline S.J.M. De Bont Yannis Duffourd Floor Duijkers Magali Avila David Geneviève Nada Houcinat Thibaud Jouan Paul Kuentz Klaske D. Lichtenbelt Joerg Betschinger 《Cell Stem Cell》2019,24(2):257-270.e8
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83.
Calbindin-D28k is a calcium binding protein that is highly expressed in the mammalian central nervous system. It has been reported that calbindin-D28k binds to and increases the activity of inositol Monophosphatase (IMPase). This is an enzyme that is involved in the homeostasis of the Inositol trisphosphate signalling cascade by catalysing the final dephosphorylation of inositol and has been implicated in the therapeutic mechanism of lithium treatment of bipolar disorder. Previously studies have shown that calbindin-D28k can increase IMPase activity by up to 250 hundred-fold. A preliminary in silico model was proposed for the interaction.Here, we aimed at exploring the shape and properties of the calbindin-IMPase complex to gain new insights on this biologically important interaction. We created several fusion constructs of calbindin-D28k and IMPase, connected by flexible amino acid linkers of different lengths and orientations to fuse the termini of the two proteins together. The resulting fusion proteins have activities 200%–400% higher the isolated wild-type IMPase. The constructs were characterized by small angle X-ray scattering to gain information on the overall shape of the complexes and validate the previous model. The fusion proteins form a V-shaped, elongated and less compact complex as compared to the model. Our results shed new light into this protein-protein interaction. 相似文献
84.
JEROME C WAKEFIELD 《World psychiatry》2007,6(3):149-156
What do we mean when we say that a mental condition is a medical disorder
rather than a normal form of human suffering or a problem in living? The status
of psychiatry as a medical discipline depends on a persuasive answer to this
question. The answers tend to range from value accounts that see disorder
as a sociopolitical concept, used for social control purposes, to scientific
accounts that see the concept as strictly factual. I have proposed a hybrid
account, the harmful dysfunction (HD) analysis, that incorporates both value
and scientific components as essential elements of the medical concept of
disorder, applying to both physical and mental conditions. According to the
HD analysis, a condition is a disorder if it is negatively valued ("harmful")
and it is in fact due to a failure of some internal mechanism to perform a
function for which it was biologically designed (i.e., naturally selected).
The implications of this analysis for the validity of symptom-based diagnostic
criteria and for challenges in cross-cultural use of diagnostic criteria are
explored, using a comparison of the application of DSM diagnostic criteria
in the U.S. and Taiwan. 相似文献
85.
Morten KJ Ashley N Wijburg F Hadzic N Parr J Jayawant S Adams S Bindoff L Bakker HD Mieli-Vergani G Zeviani M Poulton J 《Mitochondrion》2007,7(6):386-395
BACKGROUND: The quantitative loss of mitochondrial DNA (mtDNA) known as mtDNA depletion, often gives rise to liver disease. The diagnosis of mtDNA depletion syndrome is frequently imprecise, both for technical reasons and because of the lack of established age-adjusted normal ranges. We aimed to refine quantitative methods for diagnosing the hepatic type of mtDNA depletion syndrome, firstly by establishing an age-matched reference range for mitochondrial to nuclear DNA ratio (henceforth "mtDNA content") and secondly by investigating mtDNA in fibroblasts. METHODS: By comparing realtime PCR with an established method for quantifying mtDNA content we established a reference range for young children using biopsy and post-mortem material from patients <15 years. In addition, we investigated the arrangement of mtDNA in nucleoids from fibroblasts using fluorescence microscopy. RESULTS: Both methods showed that the mtDNA content of liver increases rapidly over the perinatal period. In a patient whose liver mtDNA content fell, but remained within the reference range, early investigation and age-matched controls were essential, as we found a progressive increase in muscle mtDNA copy number, respiratory chain activity and muscle power with age. In three further patients, fluorescence microscopy of the fibroblasts proved diagnostic. In one case a movement disorder was an important pointer. CONCLUSIONS: These cases highlight the (i) need for comparing mtDNA copy number data generated from patients to DNA isolated from an age-matched normal range from the tissue of interest and (ii) the utility of mtDNA staining with PicoGreen as a method to detect aberrant nucleoid morphology in mtDNA depletion patient fibroblast lines when affected tissues are not available for measuring mtDNA copy number. 相似文献
86.
摘要 目的:分析妊娠期高血压疾病(HDCP)患者影响因素,并探讨HDCP对妊娠结局和生命质量的影响。方法:选取2018年1月~2021年1月我院收治的100例HDCP患者为HDCP组,另选取同期于我院产检的健康孕产妇100例为对照组。收集两组临床资料和妊娠结局,采用36项健康调查简表(SF-36)评价两组孕产妇的生命质量。单因素及多因素Logistic回归分析HDCP的影响因素。结果:单因素及多因素Logistics回归分析显示,年龄>35岁、孕前体质量指数≥28 kg/m2、焦虑/抑郁、高血压家族史为HDCP的独立危险因素,文化程度大专及以上、孕期规律补充钙剂为HDCP的独立保护因素(P<0.05)。与对照组比较,HDCP组剖宫产、新生儿窒息、产后出血、低体重儿、胎儿窘迫比例增加(P<0.05)。与对照组比较,HDCP组躯体功能、生理职能、一般健康状况、生命活力、社会功能、情感功能、精神健康评分降低,躯体疼痛评分增加(P<0.05)。结论:HDCP受多种因素影响,其发病会对患者妊娠结局和生命质量产生不良影响,临床应做好相关预防措施。 相似文献
87.
摘要 目的:研究慢性束缚(Chronic restraint stress,CRS)诱导的广泛性焦虑障碍模型小鼠前额叶皮质miRNA表达谱的变化及其意义。方法:小鼠经过7天的CRS,通过旷场实验与高架十字迷宫实验检测小鼠是否能够表现出紧张和焦虑行为。采用高通量测序的方法,定量分析对照组与模型组小鼠前额叶皮质组织中 miRNAs的表达水平,研究CRS诱导的焦虑有关的分子表达谱。通过RT-PCR对测序结果中差异表达的miRNAs 进行验证。结果:经CRS诱导的广泛性焦虑障碍模型组小鼠,模型组在活动总距离增多(P<0.05)、平均速度(P<0.05)增快、中央停留时间减少(P<0.05)、开放臂进入次数百分比减少(P<0.01)、开放臂停留时间减少(P<0.01),与对照组相比结果均具有统计学意义,表明GAD小鼠造模成功。经高通量测序结果及生信学分析,对照组与模型组相比较,共28个上调miRNAs,34个下调miRNAs,5388个靶基因参与作用变化。上/下调的miR-GO分析结果中,主要共同参与神经系统发育、突触后密度、神经元投射、蛋白丝氨酸/苏氨酸激酶活性等过程;上/下调miR-KEGG结果中,参与共同通路主要包括轴突引导、神经营养因子信号通路、cAMP 信号通路、多巴胺能突触、MAPK信号通路等过程。结论:前额叶皮质中miR-7a-5p、miR-124-3p、miR-141-3p、miR-183-5p等miRNA变化参与广泛性焦虑障碍的发病,可能调控影响神经传导等功能。 相似文献
88.
摘要 目的:探究重症创伤患者ICU后综合征(PICS)心理障碍影响因素。方法:本次研究纳入60例重症创伤患者,按照是否存在PICS分为对照组(20例)和PICS组(40例)。进行不同治疗情况PICS心理障碍影响因素单因素分析。PICS心理障碍患者急性生理与慢性健康状况评分系统(APACHEII)和医院焦虑和抑郁量表(HADS)评分、Ogawa改良创伤评分系统、匹兹堡睡眠质量指数量表(PSQI)评分进行单因素分析,并进行PICS心理障碍的相关性分析,PICS心理障碍影响因素Logistic回归分析。结果:(1)PICS组年龄<30比例较对照组升高,30-50患者比例较对照组降低(P<0.05)。PICS组文化程度文盲和小学患者比例较对照组升高,初中和高中及以上患者比例较对照组降低(P<0.05)。(2)PICS组手术、手术时间1~3 h和>3 h、ICU时间10~14 d、镇静药物和有创机械通气患者比例较对照组升高(P<0.05)。(3)PICS组APACHEII评分<20和20~25患者比例较对照组降低,APACHEII评分25~30和>30患者比例较对照组升高(P<0.05);PICS组HADS评分<5和5~15患者比例较对照组降低,HADS评分15~25和≥25患者比例较对照组升高(P<0.05);PICS组得分低于9分的轻度损伤者和得分10~16分的中度损伤的患者比例较对照组降低,得分≥17分为重度损伤的患者比例较对照组升高(P<0.05);PICS组得分≤7分的睡眠质量较好的患者比例较对照组降低(P<0.05),得分>7分的睡眠障碍的患者比例较对照组升高(P<0.05)。(4)PICS组年龄、手术时间、ICU时间、APACHEII评分、HADS评分、PSQI得分以及创伤指数评分较对照组升高(P<0.05);(5)PICS心理障碍与年龄、文化程度、手术时间、ICU时间、镇静药物、无创机械通气、有创机械通气、APACHEII评分、HADS评分、创伤指数评分以及PSQI评分相关(P<0.05)。结论:PICS组年龄、手术时间、ICU时间、APACHEII评分和HADS评分较对照组升高;PICS心理障碍与年龄、文化程度、手术时间、ICU时间、镇静药物、无创机械通气、有创机械通气、APACHEII评分、HADS评分、创伤指数评分以及PSQI评分相关。 相似文献
89.
The Lac system of genes has been pivotal in understanding gene regulation. When the lac repressor protein binds to the correct DNA sequence, the hinge region of the protein goes through a disorder to order transition. The structure of this region of the protein is well understood when it is in this bound conformation, but less so when it is not. Structural studies show that this region is flexible. Our simulations show this region is extremely flexible in solution; however, a high concentration of salt can help kinetically trap the hinge helix. Thermodynamically, disorder is more favorable without the DNA present. 相似文献
90.