Guanosine Triphosphate

三磷酸鸟苷
  • 文章类型: Journal Article
    目的:我们旨在使用一个假设的医学案例来检查大型语言模型(LLM)对细菌性脑膜炎指南的依从性,强调它们在医疗保健中的效用和局限性。
    方法:在三个独立的会议中,向七个公众可访问的LLM(Bard,宾,克劳德-2,GTP-3.5,GTP-4,拉玛,PaLM).评估了对良好临床实践和两项国际脑膜炎指南的依从性。
    结果:在90%的LLM会话中发现了中枢神经系统感染。所有推荐的成像,而81%的人建议腰椎穿刺。仅在62%和38%的会议中提出了血液培养和特定的乳突炎检查,分别。只有38%的疗程提供了正确的经验性抗生素治疗,而抗病毒治疗和地塞米松的建议分别为33%和24%,分别。52%的人产生了误导性陈述。LLM的文本长度和性能之间没有发现显著的相关性(r=0.29,p=0.20)。在所有LLM中,GTP-4表现出最佳性能。
    结论:最新的LLM在鉴别诊断和诊断程序方面提供了有价值的建议,但在实际临床情况下,细菌性脑膜炎的治疗特异性信息存在显著差异。误导性陈述很常见,性能差异归因于每个LLM的唯一算法,而不是输出长度。
    结论:用户在考虑将LLM作为医疗决策的支持工具时,必须意识到这种局限性和性能可变性。需要进一步的研究来完善这些模型对复杂医疗场景的理解及其提供可靠信息的能力。
    We aimed to examine the adherence of large language models (LLMs) to bacterial meningitis guidelines using a hypothetical medical case, highlighting their utility and limitations in healthcare.
    A simulated clinical scenario of a patient with bacterial meningitis secondary to mastoiditis was presented in three independent sessions to seven publicly accessible LLMs (Bard, Bing, Claude-2, GTP-3.5, GTP-4, Llama, PaLM). Responses were evaluated for adherence to good clinical practice and two international meningitis guidelines.
    A central nervous system infection was identified in 90% of LLM sessions. All recommended imaging, while 81% suggested lumbar puncture. Blood cultures and specific mastoiditis work-up were proposed in only 62% and 38% sessions, respectively. Only 38% of sessions provided the correct empirical antibiotic treatment, while antiviral treatment and dexamethasone were advised in 33% and 24%, respectively. Misleading statements were generated in 52%. No significant correlation was found between LLMs\' text length and performance (r=0.29, p=0.20). Among all LLMs, GTP-4 demonstrated the best performance.
    Latest LLMs provide valuable advice on differential diagnosis and diagnostic procedures but significantly vary in treatment-specific information for bacterial meningitis when introduced to a realistic clinical scenario. Misleading statements were common, with performance differences attributed to each LLM\'s unique algorithm rather than output length.
    Users must be aware of such limitations and performance variability when considering LLMs as a support tool for medical decision-making. Further research is needed to refine these models\' comprehension of complex medical scenarios and their ability to provide reliable information.
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  • 文章类型: Journal Article
    背景:γ-谷氨酰转移酶(γ-GTP)水平升高与代谢综合征相关。我们调查了大规模人群中高γ-GTP累积暴露与心血管疾病(CVD)风险的关系。
    方法:使用韩国国民健康保险制度的全国代表性数据,纳入了1,640,127人,从2009年至2012年连续4年进行了γ-GTP测量,并随访至2019年底。对于研究期间的每一年,参与者按最高γ-GTP四分位数(0-4)的暴露次数分组,四分位数之和(0-12)定义为累积γ-GTP暴露。使用Cox比例风险模型评估CVD的风险比。
    结果:在6.4年的随访中,心肌梗死(MI)15980例(0.97%),中风14,563(0.89%),29,717(1.81%)的CVD,和25,916(1.58%)的死亡。持续暴露于高γ-GTP水平与较高的MI风险相关。中风,CVD,和死亡比那些没有这种暴露的人。MI的风险,中风,CVD,根据总累积γ-GTP,死亡率以剂量依赖性方式增加(所有趋势P<0.0001)。受试者年龄小于65岁,体重指数<25kg/m2,无高血压或脂肪肝的情况下,累积γ-GTP与MI发病率之间的关系更强,CVD,和死亡。
    结论:累积γ-GTP升高与CVD相关。γ-GTP可以更广泛地用作CVD风险的早期标志物,特别是在没有传统CVD危险因素的个体中。
    BACKGROUND: Elevated γ-glutamyl transferase (γ-GTP) levels are associated with metabolic syndrome. We investigated the association of cumulative exposure to high γ-GTP with the risk of cardiovascular disease (CVD) in a large-scale population.
    METHODS: Using nationally representative data from the Korean National Health Insurance system, 1,640,127 people with 4 years of consecutive γ-GTP measurements from 2009 to 2012 were included and followed up until the end of 2019. For each year of the study period, participants were grouped by the number of exposures to the highest γ-GTP quartile (0-4), and the sum of quartiles (0-12) was defined as cumulative γ-GTP exposure. The hazard ratio for CVD was evaluated using the Cox proportional hazards model.
    RESULTS: During the 6.4 years of follow-up, there were 15,980 cases (0.97%) of myocardial infarction (MI), 14,563 (0.89%) of stroke, 29,717 (1.81%) of CVD, and 25,916 (1.58%) of death. Persistent exposure to high γ-GTP levels was associated with higher risks of MI, stroke, CVD, and death than those without such exposure. The risks of MI, stroke, CVD, and mortality increased in a dose-dependent manner according to total cumulative γ-GTP (all P for trend <0.0001). Subjects younger than 65 years, with a body mass index <25 kg/m2, and without hypertension or fatty liver showed a stronger relationship between cumulative γ-GTP and the incidence of MI, CVD, and death.
    CONCLUSIONS: Cumulative γ-GTP elevation is associated with CVD. γ-GTP could be more widely used as an early marker of CVD risk, especially in individuals without traditional CVD risk factors.
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  • 文章类型: Multicenter Study
    骨通补片(GTP)在骨病的临床实践中是常见的。这项研究比较了GTP和非甾体抗炎药(NSAIDs)对35个GTP医疗中心KOA患者的疗效和安全性,选择性COX-2抑制剂(SCI),GTP+SCI,非选择性COX-2抑制剂(NSCI),和GTP+NSCI组。视觉模拟量表(VAS)疼痛评分,EuroQol-VAS,EuroQol5D-3L,关节疼痛缓解/消失的时间,和关节运动恢复是疗效评估。安全性评估包括接触性皮炎,胃肠道疾病,等。P值<0.05被认为是统计学上显著的。经过统计分析,SCI组和GTP+SCI组VAS改善程度优于GTP组;NSCI组关节疼痛缓解时间短于GTP组和SCI组;GTP+NSCI组关节运动恢复时间长于SCI组。此外,治疗后,各组患者的生活质量均有显著改善.NSAIDs组胃肠道不良事件发生率高于GTP组和GTP+NSAIDs组。GTP和NSAIDs对KOA患者有效,GTP更适用于有心血管和胃肠道合并症的KOA患者。本研究经北京协和医院伦理委员会(HS-1766)批准,并在中国临床试验注册中心(ChiCTR2100046391)注册。
    The Gutong Patch (GTP) is common in clinical practice for bone diseases. This study compared the efficacy and safety of GTP and nonsteroidal anti-inflammatory drugs (NSAIDs) for KOA patients from 35 medical centers assigned to GTP, selective COX-2 inhibitor (SCI), GTP + SCI, non-selective COX-2 inhibitor (NSCI), and GTP + NSCI groups. The visual analog scale (VAS) pain score, EuroQol-VAS, EuroQol 5D-3 L, time to articular pain relief / disappearance, and joint motion recovery were the efficacy assessments. Safety assessments included contact dermatitis, gastrointestinal disorders, etc. The p-value < 0.05 was considered statistically significant. After statistical analysis, the SCI and GTP + SCI groups showed better improvement of VAS than the GTP group; the time to articular pain relief in the NSCI group was shorter than that in GTP and SCI group; the time to joint motion recovery in the GTP + NSCI group was longer than that in the SCI group. Additionally, the improvement of the quality of life in all groups was significant after treatments. While the incidence of gastrointestinal adverse events in the NSAIDs group was higher than that in the GTP and GTP + NSAIDs groups. GTP and NSAIDs are effective for KOA patients, and GTP is more suitable for KOA patients with cardiovascular and gastrointestinal comorbidities. This study was approved by the Ethics Committee at Peking Union Medical College Hospital (HS-1766) and registered in the Chinese Clinical Trial Registry (ChiCTR2100046391).
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  • 文章类型: English Abstract
    Sotorasib(LUMAKRAS®)是第一种选择性结合KRASG12C并不可逆地抑制KRAS从无活性形式到活性形式的构象变化的RAS抑制剂。产生KRASG12C蛋白的基因突变,也就是索托拉西的目标,是非小细胞肺癌(NSCLC)中观察到的致癌驱动因素之一,KRASG12C突变引起构象变化,以增强下游信号的活性形式维持KRAS,导致肿瘤细胞增殖和存活。尽管KRAS在人类癌症中的作用已经有几十年了,RAS在正常细胞中的作用,RAS和GTP之间的高亲和力,高浓度的细胞内GTP,RAS蛋白的光滑表面使得研发针对RAS突变的药物很困难。然而,2013年发现了KRAS的SwitchII口袋,并报道了与KRASG12C特异性结合的化合物,导致了索托拉西的发展。Sotorasib抑制KRASG12C阳性细胞系的生长,并在植入KRASG12C阳性细胞系的小鼠模型中抑制肿瘤生长。在临床试验中,在每天口服960mg索托拉西的KRASG12C阳性晚期NSCLC患者中,有37.4%的患者观察到客观缓解.没有剂量限制性毒性和其他不良事件是可以容忍的。Sotorasib于2021年3月被指定为孤儿药,并于2022年1月被批准用于KRASG12C阳性,不可切除/复发性NSCLC,在日本一线治疗后进展。
    Sotorasib (LUMAKRAS®) is the first RAS inhibitor that selectively binds to KRAS G12C and irreversibly inhibits the conformational change from the inactive to active form of KRAS. The gene mutation that produces KRAS G12C protein, which is the target of sotorasib, is one of the oncogenic drivers observed in non-small cell lung cancer (NSCLC), and the KRAS G12C mutation causes conformational changes to maintain KRAS in an active form enhancing downstream signals, leading to tumor cell proliferation and survival. Although the role of KRAS in human cancers has been known for decades, role of RAS in normal cells, the high affinity between RAS and GTP, high concentration of intracellular GTP, and the smooth surface of RAS protein makes it difficult to develop drugs targeting RAS mutation for a long time. However, the discovery of the Switch II pocket of KRAS in 2013 and the report of compounds that specifically bind to KRAS G12C led to the development of sotorasib. Sotorasib inhibited the growth of KRAS G12C positive cell lines and suppressed tumor growth in a mouse model implanted with the KRAS G12C positive cell line. In clinical trials, objective responses were seen in 37.4% of patients with KRAS G12C positive advanced NSCLC taking 960mg sotorasib orally per day. There were no dose-limiting toxicities and other adverse events were tolerable. Sotorasib was designated as an orphan drug in March 2021 and approved in January 2022 for KRAS G12C positive unresectable/recurrent NSCLC that has progressed after 1st line therapy in Japan.
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  • 文章类型: Journal Article
    目的:我们旨在确定儿童期的血清尿酸(SUA)和体重指数(BMI)轨迹是否与青春期的肝酶具有纵向关联。
    方法:我们使用来自梨花出生和生长队列的数据进行了一项研究。通过基于组的轨迹建模定义了5、7和9年的SUA(n=203)和BMI(n=206)的个体轨迹。此外,在11至12岁时收集肝功能酶(天冬氨酸氨基转移酶[AST],丙氨酸转氨酶[ALT],和γ-谷氨酰转移酶[γ-GTP])(n=206)。使用广义线性模型,评估SUA轨迹和BMI轨迹对肝功能酶的影响.我们还评估了SUA和BMI轨迹对肝酶的相互作用。
    结果:对于轨迹模式,SUA和BMI被分为两个不同的组(高或低).儿童时期SUA和BMI的轨迹与11-12岁时的肝酶水平呈正相关。结果表明,SUA和BMI轨迹对肝酶的联合作用在高风险组(高SUA-高BMI轨迹组)中的平均值高于低风险组(低SUA-低BMI轨迹组)ALT和γ-GTP,分别。当调整协变量时,它仍然是显著的关联。此外,BMI和SUA轨迹的交互作用表现出显著的协同作用。
    结论:儿童时期SUA和BMI轨迹升高与青少年时期肝酶升高相关。这一发现表明,SUA和BMI的早期干预可能需要优化肝酶,作为晚年相关疾病发展的潜在标志物。
    We aimed to determine whether serum uric acid (SUA) and body mass index (BMI) trajectories in childhood have longitudinal association with liver enzymes in adolescence.
    We conducted a study using data from the Ewha Birth and Growth Cohort. Individual trajectories of SUA (n = 203) and BMI (n = 206) from 5, 7, and 9 years were defined by group-based trajectory modeling. Also, liver function enzymes were collected at 11 to 12 year of age (Aspartate Aminotransferase [AST], Alanine transaminase [ALT], and Gamma-glutamyl transferase [γ-GTP]) (n = 206). Using a generalized linear model, the effects of SUA trajectory and BMI trajectory on liver function enzymes were assessed. We also assessed the interaction effect of SUA and BMI trajectories on liver enzymes.
    For trajectory patterns, both SUA and BMI were classified into two distinct groups (High or Low). Both trajectory of SUA and BMI in childhood were positively associated with levels of liver enzymes at 11-12 years of age. The results showed that the combined effect of SUA and BMI trajectories on liver enzymes had a higher means in high-risk group (high SUA-high BMI trajectories group) than in low-risk group (low SUA-low BMI trajectories group) for ALT and γ-GTP, respectively. It remained significant association when adjusted for covariates. In addition, the interaction of BMI and SUA trajectories showed a significant synergistic effect.
    Elevated childhood SUA and BMI trajectories are associated with increased liver enzymes in beginning of adolescent. This finding suggesting that early interventions in SUA and BMI may need for optimization of liver enzymes as potential marker for development of related disease in later life.
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  • 文章类型: Journal Article
    目的:本研究旨在培养基层人民作为心理健康守门人的能力。它将评估看门人培训计划(GTP)对看门人行为的有效性,意识,态度,和精神帮助寻求意图。设计:分两个阶段进行评估的研究方法。第一阶段:逐户进行横断面探索性调查。第二阶段:准实验设计,在0、6和12个月进行多次随访。方法:使用标准化工具收集数据,如心理健康知识问卷(MHKQ),社区对精神病的态度(CAMIS),心理帮助寻求意图(MHSIS)和看门人行为量表(GBS)。对于第一阶段,将在Koraga部落的选定殖民地中进行逐户调查,以确定他们的意识,态度,以及寻求常见心理健康问题意向的心理帮助。第二阶段包括确定选定部落殖民地的领导人/代表,让他们参与GTP。前测和多次后测将在第2阶段在0、6、12个月进行。该研究由印度医学研究委员会资助,从2021年8月16日起为期3年。讨论:精神疾病的治疗差距仍然是一个非常令人关注的问题。循证研究促进了处理社区心理健康问题的任务转移方法。针对社会弱势群体的诸如GTP之类的能力建设计划非常重要,尤其是在中低收入国家中。影响:这种基于需求的GTP,将确保社会的心理健康急救。在家门口及早发现有心理健康问题的人对疾病的预后有巨大影响,缩小治疗差距,减少病耻感。
    Aim: This study aims to build the capacity of the people at grass root level as gatekeepers of mental health. It will assess the effectiveness of the Gatekeeper Training Program (GTP) on gatekeeper behaviour, awareness, attitude, and mental help seeking intention. Design: An evaluative research approach in two phases. Phase 1: Cross-sectional house-to-house exploratory survey. Phase 2: A quasi-experimental design with multiple follow ups at 0, 6 and 12 months. Method: Data will be collected using standardized tools like Mental Health Knowledge Questionnaire (MHKQ), Community Attitude towards Mentally Ill (CAMIS), Mental Help Seeking Intention (MHSIS) and Gatekeeper Behavior Scale (GBS). For Phase 1, a house-to-house survey will be conducted among the selected colonies of Koraga tribe to determine their awareness, attitude, and mental help seeking intention regarding common mental health problems. Phase 2 includes identification of the leaders/representatives of the selected tribal colonies, and involving them in GTP. Pre-test and multiple post-test will be conducted in Phase 2 at 0, 6, 12 months.  The study is funded by Indian Council of Medical Research from 16 August 2021 for 3 years duration. Discussion: Treatment gap in psychiatric disorders remains an issue of great concern. Evidence based research promotes task shifting approaches in dealing with mental health problems in the community. Capacity building programs like GTP for the underprivileged section of the society are important especially in low and middle income group of countries. Impact: This need based GTP, will ensure mental health first aid in the society. Early identification of people with mental health problems at their doorsteps has huge impact on the prognosis of the illness, closing the treatment gap and stigma reduction.
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  • 文章类型: Journal Article
    背景:由于塑料制品在日常生活中的广泛使用,邻苯二甲酸酯的暴露无处不在,并影响几种健康结果,包括代谢性疾病。在这项研究中,我们评估了儿童时期邻苯二甲酸盐暴露对青春期肝功能的影响.方法:在164名梨花出生和生长队列研究参与者中,在两个暴露期(儿童年龄为3-5岁和7-9岁)进行了随访,在10-15岁时进行了126次随访。探讨两个时期邻苯二甲酸盐暴露与肝酶水平(ALT,AST,γ-GTP)在青春期,分析组间差异和剂量-反应关系。此外,我们根据两个时期的联合暴露水平(高或低)调查了各组之间肝酶的差异.评价了邻苯二甲酸酯和BMI对肝酶水平的交互作用,按性别分层。结果:在3-5岁的暴露期,ALT水平倾向于增加MECPP水平增加,而γ-GTP水平倾向于随着MiBP增加,MnBP,和∑DBP水平升高。此外,与暴露量较低的组相比,在两个时间点始终高水平的邻苯二甲酸酯暴露组的肝酶水平较高.特别是,3-5岁儿童中某些邻苯二甲酸酯代谢物与BMI之间的交互作用仅影响女孩青春期的AST和γ-GTP水平。
    结论:儿童期日常生活中邻苯二甲酸盐的暴露会影响青春期的肝酶水平。肝酶水平升高与代谢综合征的发展有关,这意味着在童年时期应该注意邻苯二甲酸盐的暴露。
    Phthalate exposure is ubiquitous due to the widespread use of plastic products in daily life, and affects several health outcomes, including metabolic diseases. In this study, we evaluated the effects of phthalate exposure in childhood on liver function in adolescence.  METHODS: Among 164 Ewha Birth and Growth Cohort Study participants followed up during two exposure periods (when the children were aged 3-5 and 7-9 years), 126 were followed up at age 10-15 years. To investigate the relationship between phthalate exposure during the two periods and liver enzyme levels (ALT, AST, γ-GTP) in adolescence, differences between groups and the dose-response relationship were analyzed. In addition, we investigated differences in liver enzymes between groups based on the combined exposure levels (high or low) during the two periods. The interaction effect between phthalates and BMI on liver enzyme levels was evaluated, stratified by sex.  RESULTS: In the 3-5 year-old exposure period, ALT levels tended to increase as MECPP levels increased, while γ-GTP levels tended to increase as MiBP, MnBP, and ∑DBP levels increased. In addition, the group exposed to consistently high levels of phthalates at both time points had higher liver enzyme levels compared to the group that had lower exposure. In particular, the interaction effect between some phthalate metabolites and BMI in 3-5 year olds affected AST and γ-GTP levels in adolescence only in girls.
    Exposure to phthalates in daily life during childhood affects liver enzyme levels in adolescence. Elevated liver enzyme levels are associated with the development of metabolic syndrome, implying that attention should be paid to phthalate exposure during childhood.
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  • 文章类型: Journal Article
    Enga,GTP酶包含两个GTP结合域[GD1,GD2],和C末端KH结构域显示参与核糖体成熟的后期阶段。在成熟的中间阶段,EngA与核糖体亚基的关联对于完整的核糖体成熟至关重要。然而,这种关联被证明依赖于核苷酸结合的组合.这种核苷酸依赖性缔合趋势归因于不同核苷酸结合组合之间发生的构象变化。因此,探索构象变化,进行了不同核苷酸结合组合中枯草芽孢杆菌EngA的全原子分子动力学模拟,以及活性位点中是否存在Mg2。Mg2+的存在以及GD2活性位点的结合核苷酸决定了GD2-Sw-II的迁移率,但是GD1-Sw-II迁移率没有显示任何核苷酸或Mg2依赖性运动。然而,GD1-Sw-II二级构象显示受GD2核苷酸结合状态的影响。通过动态网络分析也观察到GD2活性位点与GD1-Sw-II之间的这种变构连接。Further,当GD1与GTP-Mg2结合时,对GD1-KH界面相互作用的探索表现出更有吸引力的趋势。此外,Mg2+的存在稳定了活性位点水,并且还增加了结合的GTP的α-和γ-磷酸盐之间的距离。奇怪的是,GD1活性位点中的三个水分子和GD2活性位点中的仅一个水分子是稳定的。这表明与GD2相比,GD1中GTP水解的可能性更大。由RamaswamyH.Sarma沟通。
    EngA, a GTPase contains two GTP binding domains [GD1, GD2], and the C-terminal KH domain shown to be involved in the later stages of ribosome maturation. Association of EngA to the ribosomal subunit in the intermediate stage of maturation is essential for complete ribosome maturation. However, this association was shown to be dependent on the nucleotide bound combinations. This nucleotide dependent association tendency is attributed to the conformational changes that occur among different nucleotide bound combinations. Therefore, to explore the conformational changes, all-atom molecular dynamics simulations for Bacillus subtilis EngA in different nucleotide bound combinations along with the presence or absence of Mg2+ in the active-sites were carried out. The presence of Mg2+ along with the bound nucleotide at the GD2 active-site dictates the GD2-Sw-II mobility, but the GD1-Sw-II mobility has not shown any nucleotide or Mg2+ dependent movement. However, the GD1-Sw-II secondary conformations are shown to be influenced by the GD2 nucleotide bound state. This allosteric connection between the GD2 active-site and the GD1-Sw-II is also observed through the dynamic network analysis. Further, the exploration of the GD1-KH interface interactions exhibited a more attractive tendency when GD1 is bound to GTP-Mg2+. In addition, the presence of Mg2+ stabilizes active-site water and also increases the distances between the α- and γ- phosphates of the bound GTP. Curiously, three water molecules in the GD1 active-site and only one water molecule in the GD2 active-site are stabilized. This indicates that the probability of GTP hydrolysis is more in GD1 compared to GD2.Communicated by Ramaswamy H. Sarma.
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  • 文章类型: Journal Article
    FtsZ丝是细菌Z环的主要结构组分,并且是细菌分裂的驱动器。在存在GTP类似物的情况下,来自一些革兰氏阳性细菌的FtsZ的晶体结构表明,“紧张”的构象。阐明这种时态形式是否是细丝中的主要形式仍然很重要。使用动态核极化(DNP)固态核磁共振(NMR)和差分同位素标记,我们直接检测了位于GTP结合的野生型(WT)大肠杆菌FtsZ丝单体间界面的残基。我们结合化学位移预测,同源建模,和异核偶极再偶联技术来表征大肠杆菌FtsZ细丝界面,并证明活性细丝中的单体呈紧张构象。重要性细菌复制依赖于细胞骨架蛋白FtsZ,形成支撑和募集其他必需分裂蛋白的细丝。虽然FtsZ单体在生物体中得到了很好的研究,许多问题仍然是关于如何形成和功能的细丝。最近,在金黄色葡萄球菌中鉴定出第二种单体形式,对FtsZ的结构和功能具有深远的影响。然而,到目前为止,这种形式尚未在金黄色葡萄球菌之外直接观察到。在这项研究中,我们使用固态NMR和动态核极化(DNP)直接研究了大肠杆菌FtsZ的细丝,以证明大肠杆菌FtsZ细丝主要由这第二个,单体的“时态”形式。这项工作是第一次GTP绑定,野生型FtsZ细丝已直接以原子分辨率进行了研究,是FtsZ细丝研究的重要一步。
    FtsZ filaments are the major structural component of the bacterial Z ring and are drivers of bacterial division. Crystal structures for FtsZ from some Gram-positive bacteria in the presence of GTP analogs suggest the possibility of a high-energy, \"tense\" conformation. It remains important to elucidate whether this tense form is the dominant form in filaments. Using dynamic nuclear polarization (DNP) solid-state nuclear magnetic resonance (NMR) and differential isotopic labeling, we directly detected residues located at the intermonomer interface of GTP-bound wild-type (WT) Escherichia coli FtsZ filaments. We combined chemical shift prediction, homology modeling, and heteronuclear dipolar recoupling techniques to characterize the E. coli FtsZ filament interface and demonstrated that the monomers in active filaments assume a tense conformation. IMPORTANCE Bacterial replication is dependent on the cytoskeletal protein FtsZ, which forms filaments that scaffold and recruit other essential division proteins. While the FtsZ monomer is well studied across organisms, many questions remain about how the filaments form and function. Recently, a second monomer form was identified in Staphylococcus aureus that has far-reaching implications for FtsZ structure and function. However, to date, this form has not been directly observed outside S. aureus. In this study, we used solid-state NMR and dynamic nuclear polarization (DNP) to directly study the filaments of E. coli FtsZ to demonstrate that E. coli FtsZ filaments are primarily composed of this second, \"tense\" form of the monomer. This work is the first time GTP-bound, wild-type FtsZ filaments have been studied directly at atomic resolution and is an important step forward for the study of FtsZ filaments.
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  • 文章类型: Journal Article
    γ-谷氨酰转移酶(γ-GTP)水平升高与代谢综合征相关,糖耐量受损,和胰岛素抵抗,这是2型糖尿病的危险因素。我们的目的是调查高γ-GTP水平的累积暴露与糖尿病风险的关系。
    使用韩国国民健康保险制度的全国代表性数据,从2005年至2009年连续接受5次健康检查的346,206名没有糖尿病的人被追踪到2018年底。高γ-GTP水平定义为最高四分位数,暴露于高γ-GTP水平的次数范围为0到5。使用多变量Cox比例风险模型分析糖尿病的危险比(HR)和95%置信区间(CI)。
    平均随访时间为9.2±1.0年,在此期间,15,183(4.4%)患者发展为糖尿病。累积暴露于高γ-GTP水平的糖尿病发病率和风险呈线性增加。在调整了可能的混杂因素后,与从未有过高γ-GTP水平的受试者相比,连续5次高γ-GTP水平的受试者的糖尿病HR在男性中为2.60(95%CI,2.47~2.73),在女性中为3.05(95%CI,2.73~3.41).在各种亚组和敏感性分析中观察到类似的结果。
    高γ-GTP水平的累积暴露与糖尿病风险之间存在线性关系。应考虑监测和降低γ-GTP水平以预防普通人群中的糖尿病。
    Elevated γ-glutamyl transferase (γ-GTP) level is associated with metabolic syndrome, impaired glucose tolerance, and insulin resistance, which are risk factors for type 2 diabetes. We aimed to investigate the association of cumulative exposure to high γ-GTP level with risk of diabetes.
    Using nationally representative data from the Korean National Health Insurance system, 346,206 people who were free of diabetes and who underwent 5 consecutive health examinations from 2005 to 2009 were followed to the end of 2018. High γ-GTP level was defined as those in the highest quartile, and the number of exposures to high γ-GTP level ranged from 0 to 5. Hazard ratio (HR) and 95% confidence interval (CI) for diabetes were analyzed using the multivariable Cox proportional-hazards model.
    The mean follow-up duration was 9.2±1.0 years, during which 15,183 (4.4%) patients developed diabetes. There was a linear increase in the incidence rate and the risk of diabetes with cumulative exposure to high γ-GTP level. After adjusting for possible confounders, the HR of diabetes in subjects with five consecutive high γ-GTP levels were 2.60 (95% CI, 2.47 to 2.73) in men and 3.05 (95% CI, 2.73 to 3.41) in women compared with those who never had a high γ-GTP level. Similar results were observed in various subgroup and sensitivity analyses.
    There was a linear relationship between cumulative exposure to high γ-GTP level and risk of diabetes. Monitoring and lowering γ-GTP level should be considered for prevention of diabetes in the general population.
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