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  • 文章类型: Journal Article
    OBJECTIVE: To determine the effectiveness of simulator training on basic arthroscopic skills utilizing a novel, low-cost arthroscopic triangulation training system.
    METHODS: A randomized controlled trial of subjects without prior arthroscopy training was conducted, with participants randomized to receive either a fixed protocol of simulation training on a triangulation simulation model (30 minutes of training for 4 consecutive days), or no training. On Days 1 and 5, all participants were evaluated on 3 simulated arthroscopic tasks by an independent observer. Variables analyzed included how many times portals were changed, the time it took to complete the tasks, and the task completion rate.
    METHODS: Arthrex Inc., Naples, FL.
    METHODS: Thirty-six participants (92% male, average 28 ± 5 years) with no prior arthroscopy training were randomized into 2 groups, with 17 in the training group (T) and 19 in the no-training group (NT).
    RESULTS: On Day 1, there was no difference in rate of task completion between the T group and NT groups (41% versus 53%, p = 0.52). On Day 5, significantly more participants in the T group completed all tasks compared to the NT group (100% versus 63%, p = 0.008). Participants in the T group had significantly improved task completion times on Day 5 versus Day 1 (p < 0.05). Participants in the NT group had a significantly improved task completion time for Task 1 on Day 5 versus Day 1 (p = 0.037); no differences were found for Tasks 2 or 3. On Day 5, participants in the T group required significantly fewer portal changes compared to the NT group (2.35 ± 2.29 versus 6.95 ± 8.55, p = 0.039).
    CONCLUSIONS: Simulation training on a simple, low-cost arthroscopic triangulation training system resulted in an overall improvement in arthroscopic probing and triangulation skills within 1 week of training, with significantly decreased task completion times and increased efficiency of movement.
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  • 文章类型: Journal Article
    Renal agenesis and hypodysplasia (RHD) are major causes of pediatric chronic kidney disease and are highly genetically heterogeneous. We conducted whole-exome sequencing in 202 case subjects with RHD and identified diagnostic mutations in genes known to be associated with RHD in 7/202 case subjects. In an additional affected individual with RHD and a congenital heart defect, we found a homozygous loss-of-function (LOF) variant in SLIT3, recapitulating phenotypes reported with Slit3 inactivation in the mouse. To identify genes associated with RHD, we performed an exome-wide association study with 195 unresolved case subjects and 6,905 control subjects. The top signal resided in GREB1L, a gene implicated previously in Hoxb1 and Shha signaling in zebrafish. The significance of the association, which was p = 2.0 × 10-5 for novel LOF, increased to p = 4.1 × 10-6 for LOF and deleterious missense variants combined, and augmented further after accounting for segregation and de novo inheritance of rare variants (joint p = 2.3 × 10-7). Finally, CRISPR/Cas9 disruption or knockdown of greb1l in zebrafish caused specific pronephric defects, which were rescued by wild-type human GREB1L mRNA, but not mRNA containing alleles identified in case subjects. Together, our study provides insight into the genetic landscape of kidney malformations in humans, presents multiple candidates, and identifies SLIT3 and GREB1L as genes implicated in the pathogenesis of RHD.
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  • 文章类型: Journal Article
    固体废物,包括城市垃圾及其管理,对于大多数城市和气候变化的主要贡献者来说,这是一个重大挑战。可以通过从城市固体废物流中回收和再循环资源来减少温室气体排放。在圣保罗,巴西,回收合作社在提供包括收集在内的回收服务方面发挥着至关重要的作用,分离,清洁,放养,和可回收资源的销售。本研究试图衡量回收合作社合作社实现的温室气体减排量,并强调其社会经济效益。方法包括参与者观察,结构化面试,问卷申请,以及使用清洁发展机制方法对回收利用进行温室气体核算。结果表明,回收合作社可以实现重要的能源节约和温室气体减排,并建议Cooperpires和其他类似的回收组织有机会参与碳信用市场。基于这些发现,作者为回收商创建了一个简单的温室气体核算计算器,以估算其减排量。
    Solid waste, including municipal waste and its management, is a major challenge for most cities and among the key contributors to climate change. Greenhouse gas emissions can be reduced through recovery and recycling of resources from the municipal solid waste stream. In São Paulo, Brazil, recycling cooperatives play a crucial role in providing recycling services including collection, separation, cleaning, stocking, and sale of recyclable resources. The present research attempts to measure the greenhouse gas emission reductions achieved by the recycling cooperative Cooperpires, as well as highlight its socioeconomic benefits. Methods include participant observation, structured interviews, questionnaire application, and greenhouse gas accounting of recycling using a Clean Development Mechanism methodology. The results show that recycling cooperatives can achieve important energy savings and reductions in greenhouse gas emissions, and suggest there is an opportunity for Cooperpires and other similar recycling groups to participate in the carbon credit market. Based on these findings, the authors created a simple greenhouse gas accounting calculator for recyclers to estimate their emissions reductions.
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  • 文章类型: Journal Article
    OBJECTIVE: To examine the impact of physical fitness (PF) on the association between fasting serum triglycerides (FTG) and diabetes risk and whether temporal changes in FTG predict diabetes risk in healthy middle-aged men.
    METHODS: FTG and PF (bicycle exercise test) were measured in 1962 men aged 40-59 years in 1972-1975 (Survey 1) and repeated in 1387 still healthy men on average 7.3 years later (Survey 2). Diabetes was diagnosed according to WHO 1985-criteria.
    RESULTS: During 35 years follow-up 202/1962 (10.3%) men developed diabetes. Compared with the lowest, the upper FTG tertile had a 2.58-fold (95% CI: 1.81-3.74) diabetes risk adjusted for age, fasting blood glucose and maternal diabetes, and a 2.29-fold (95%CI: 1.60-3.33) when also adjusting for PF. Compared with unchanged (±25%) FTG levels (n=664), FTG reduction of more than 25% (n=261) was associated with 56% lower (0.44; 95% CI: 0.24-0.75) diabetes risk, while FTG increase of more than 25% (n=462) was associated with similar risk. These associations were unchanged when adjusted for PF and PF change.
    CONCLUSIONS: High FTG-levels predicted long-term diabetes risk in healthy middle-aged men, and the association was only modestly weakened when adjusted for PF. A reduction in FTG was associated with decreased diabetes risk.
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  • 文章类型: Journal Article
    根据对邻苯二甲酸二丁酯进行化学案例研究的经验教训,开发了一种在化学风险评估中评估和整合基因组数据的方法。首先根据EPA的指导和科学界的建议开发了案例研究原型方法。选择邻苯二甲酸二丁酯(DBP)进行案例研究。邻苯二甲酸二丁酯病例研究的范围确定阶段是通过考虑可用的DBP基因组数据进行的,连同整个数据集,他们是否可以为各种风险评估方面提供信息,比如毒理学,毒物动力学,和剂量反应。对可用的邻苯二甲酸二丁酯数据集进行加权以用于风险评估的描述提供了考虑基因组数据用于未来化学评估的示例。作为进行范围界定过程的结果,两个问题--DBP毒理学数据是否告知1)作用机制或模式?,和2)毒理学的种间差异?-被选择作为案例研究的重点。一般方法的原则包括将基因组学数据与所有其他数据结合起来考虑,以确定它们为风险评估的各种定性和/或定量方面提供信息的能力,并评估可用的基因组和毒性结果数据之间关于研究可比性和表型锚定的关系。根据DBP案例研究的经验,我们提出了在化学评估中整合基因组数据的建议和一般方法,以推进在风险评估中利用21世纪数据的更广泛努力.
    An approach for evaluating and integrating genomic data in chemical risk assessment was developed based on the lessons learned from performing a case study for the chemical dibutyl phthalate. A case study prototype approach was first developed in accordance with EPA guidance and recommendations of the scientific community. Dibutyl phthalate (DBP) was selected for the case study exercise. The scoping phase of the dibutyl phthalate case study was conducted by considering the available DBP genomic data, taken together with the entire data set, for whether they could inform various risk assessment aspects, such as toxicodynamics, toxicokinetics, and dose-response. A description of weighing the available dibutyl phthalate data set for utility in risk assessment provides an example for considering genomic data for future chemical assessments. As a result of conducting the scoping process, two questions--Do the DBP toxicogenomic data inform 1) the mechanisms or modes of action?, and 2) the interspecies differences in toxicodynamics?--were selected to focus the case study exercise. Principles of the general approach include considering the genomics data in conjunction with all other data to determine their ability to inform the various qualitative and/or quantitative aspects of risk assessment, and evaluating the relationship between the available genomic and toxicity outcome data with respect to study comparability and phenotypic anchoring. Based on experience from the DBP case study, recommendations and a general approach for integrating genomic data in chemical assessment were developed to advance the broader effort to utilize 21st century data in risk assessment.
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  • 文章类型: Journal Article
    目的:在临床研究中,评估脊髓损伤中残留的纤维束存在严重困难,而弥散张量成像(DTI)可以评估纤维结构完整性的改变。出于这个原因,本研究旨在通过各向异性分数(FA)变化和纤维追踪模式确定慢性创伤性脊髓损伤(SCI)患者残余纤维束结构完整性的变化.
    方法:使用3.0-TMR扫描仪对4名创伤性SCI患者和3名健康志愿者进行T2加权和弥散加权成像。获得纤维跟踪图后,测量和分析残留和远程正常和健康脐带的FA值。
    结果:扩散张量纤维束成像显示损伤索中纤维束的明显破坏。在健康对照受试者中,平均FA值范围为0.545~0.601,而所有SCI患者的残余纤维(0.220±0.121)和远程正常纤维(0.535±0.101)的FA值都降低.患者的残余纤维和远程正常纤维之间的FA值也存在统计学差异(P=0.000),其残余纤维和健康对照纤维之间的FA值也存在统计学差异(P=0.000)。远程正常和健康脐带之间没有发现显着差异(P=0.312)。
    结论:在残余纤维中观察到特定的FA变化,提示DTI可能是评估SCI患者残余血管的有用工具。
    OBJECTIVE: In clinical studies, evaluating residual fiber tracts in spinal cord injuries poses serious difficulties, whereas diffusion tensor imaging (DTI) can assess alterations in fiber structural integrity. For this reason, this study aimed to determine changes in the structural integrity of residual fiber tracts via fractional anisotropy (FA) variations and fiber-tracking patterns in patients with chronic traumatic spinal cord injury (SCI).
    METHODS: T2-weighted and diffusion-weighted imaging was performed on four traumatic SCI patients and three healthy volunteers using a 3.0-T MR scanner. After obtaining fiber-tracking maps, FA values were measured and analyzed in residual and remote normal and healthy cords.
    RESULTS: Diffusion tensor tractography showed obvious destruction of fiber tracts in injured cords. In the healthy control subjects, averaged FA values ranged from 0.545 to 0.601, whereas all SCI patients had decreased FA values in both residual (0.220 ± 0.121) and remote normal fibers (0.535 ± 0.101). There were also statistically significant differences in FA values between residual and remote normal fibers in patients (P = 0.000) and between their residual and healthy control fibers (P = 0.000). No significant difference was found between remote normal and healthy cords (P = 0.312).
    CONCLUSIONS: Specific FA variations were observed in residual fibers, suggesting that DTI may be a useful tool for evaluating residual tracts in SCI patients.
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  • 文章类型: Journal Article
    Androst-5-ene-3β,17β-diol (ADIOL) and 5α-androstane-3β,17β-diol (3β-DIOL), metabolites of dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT), respectively, are known to possess estrogenic properties. To better understand their hormonal action and roles in the proliferation of breast cancer (BC) cells, we studied their binding to sex-hormone receptors in estrogen receptor (ER)-positive (ZR-75-1 and T-47D) and ER-negative (MDA-MB-231) human BC cells. The results demonstrated that estradiol (E2), ADIOL and 3β-DIOL stimulated the proliferation of ZR-75-1 and T-47D cells, but had no effect on ER-negative cells. In the presence of estradiol, ADIOL and 3β-DIOL inhibited the estrogen-stimulated BC cell growth. This inhibition was counteracted by anti-androgens, which were unable to affect the ADIOL and 3β-DIOL stimulatory effects in E2-free medium. On the other hand, in the presence of tamoxifen, ADIOL and 3β-DIOL showed an additional anti-proliferative activity on hormone-sensitive BC cells compared with tamoxifen treatment alone. These results are similar to previous reports obtained using MCF-7 cells, which confirmed that ADIOL and 3β-DIOL stimulated estrogen-dependent BC cell growth via ERs, but inhibited growth via androgen receptors (ARs). Several steroids bind to both ER and AR in a different preference and degree, i.e. E2>estrone (E1)>ADIOL>3β-DIOL>testosterone (T)>DHT for ER and DHT>T>3β-DIOL>ADIOL>E1>E2 for AR. The relative binding affinities of ADIOL, 3β-DIOL, and E2 corresponded well to their respective potential in stimulating cell proliferation of ZR-75-1 and T-47D cells in our results. The intrinsic relationship between cell proliferation effects and binding affinities for receptors of several steroids was revealed here by a combined binding and cell study. This article is part of a Special Issue entitled \'Synthesis and biological testing of steroid derivatives as inhibitors\'.
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  • 文章类型: Journal Article
    作为较大案例研究的一部分,对邻苯二甲酸二丁酯(DBP)和男性生殖发育影响的毒性基因组数据集进行了评估,以测试将基因组数据纳入风险评估的方法。DBP毒理基因组数据集由来自已发表文献的九项体内研究组成,这些研究在妊娠期间将大鼠暴露于DBP,并评估了雄性胎儿的睾丸或沃尔夫导管中的基因表达变化。这项工作侧重于定性评估,基于缺乏可用的剂量反应数据,DBP毒理基因组数据集,以假设男性生殖发育结果的作用模式和机制,发生在较低的剂量范围内。在基因和途径水平上对大鼠睾丸的8项DBP毒理基因组学研究进行了证据权重评估。结果表明,DBP诱导类固醇生成途径和脂质/甾醇/胆固醇转运途径中的基因下调,以及对早期基因/生长/分化的影响,转录,过氧化物酶体增殖物激活受体信号和睾丸中的凋亡途径。由于两种既定的行动模式(MOA),降低胎儿睾丸睾酮产生和Insl3基因表达,解释子宫内DBP暴露后在大鼠中观察到的一些但不是全部的睾丸效应,其他MOA可能会有效。对一项DBP微阵列研究的重新分析确定了细胞信号传导中的其他途径,新陈代谢,激素,疾病,和细胞粘附的生物过程。这些推测的新通路可能与DBP对睾丸的影响有关,目前无法解释。这个关于DBP的案例研究确定了在风险评估中使用毒物基因组数据的数据空白和研究需求。此外,这项研究展示了一种在人类健康风险评估中评估毒物基因组数据的方法,该方法可应用于未来的化学品.
    An evaluation of the toxicogenomic data set for dibutyl phthalate (DBP) and male reproductive developmental effects was performed as part of a larger case study to test an approach for incorporating genomic data in risk assessment. The DBP toxicogenomic data set is composed of nine in vivo studies from the published literature that exposed rats to DBP during gestation and evaluated gene expression changes in testes or Wolffian ducts of male fetuses. The exercise focused on qualitative evaluation, based on a lack of available dose-response data, of the DBP toxicogenomic data set to postulate modes and mechanisms of action for the male reproductive developmental outcomes, which occur in the lower dose range. A weight-of-evidence evaluation was performed on the eight DBP toxicogenomic studies of the rat testis at the gene and pathway levels. The results showed relatively strong evidence of DBP-induced downregulation of genes in the steroidogenesis pathway and lipid/sterol/cholesterol transport pathway as well as effects on immediate early gene/growth/differentiation, transcription, peroxisome proliferator-activated receptor signaling and apoptosis pathways in the testis. Since two established modes of action (MOAs), reduced fetal testicular testosterone production and Insl3 gene expression, explain some but not all of the testis effects observed in rats after in utero DBP exposure, other MOAs are likely to be operative. A reanalysis of one DBP microarray study identified additional pathways within cell signaling, metabolism, hormone, disease, and cell adhesion biological processes. These putative new pathways may be associated with DBP effects on the testes that are currently unexplained. This case study on DBP identified data gaps and research needs for the use of toxicogenomic data in risk assessment. Furthermore, this study demonstrated an approach for evaluating toxicogenomic data in human health risk assessment that could be applied to future chemicals.
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  • 文章类型: Journal Article
    进行了一个案例研究,使用邻苯二甲酸二丁酯(DBP),探索一种在风险评估中使用毒物基因组数据的方法。与DBP相关的男性生殖发育结果相关的毒性和毒性基因组数据集被共同考虑,以获取有关作用模式和机制的信息。在这份手稿中,我们描述了DBP毒理学数据库的案例研究评估,重点识别男性生殖发育的全谱效应。对数据进行了评估,以1)评估低剂量和低发生率的发现,以及2)在没有完善的作用方式(MOA)的情况下确定男性生殖毒性终点。这些努力导致了在风险评估背景下对毒性和毒性基因组学研究的数据空白和研究需求的表征。Further,在毒性数据集中识别具有无法解释的MOA的终点对于随后评估毒性基因组数据集评估可以提供的机制信息很有用.在MOA背景下对毒理学数据集的广泛分析为DBP提供了信息资源,以尝试假设MOA(对于没有完善的MOA的终点),并将毒理学基因组和其他机理数据表型锚定到毒性终点和可用的毒理学数据。本案例研究是为风险评估开发毒理学数据源所采取的步骤的一个例子。无论是在一般情况下,特别是包括毒物基因组数据的风险评估。
    A case study was conducted, using dibutyl phthalate (DBP), to explore an approach to using toxicogenomic data in risk assessment. The toxicity and toxicogenomic data sets relative to DBP-related male reproductive developmental outcomes were considered conjointly to derive information about mode and mechanism of action. In this manuscript, we describe the case study evaluation of the toxicological database for DBP, focusing on identifying the full spectrum of male reproductive developmental effects. The data were assessed to 1) evaluate low dose and low incidence findings and 2) identify male reproductive toxicity endpoints without well-established modes of action (MOAs). These efforts led to the characterization of data gaps and research needs for the toxicity and toxicogenomic studies in a risk assessment context. Further, the identification of endpoints with unexplained MOAs in the toxicity data set was useful in the subsequent evaluation of the mechanistic information that the toxicogenomic data set evaluation could provide. The extensive analysis of the toxicology data set within the MOA context provided a resource of information for DBP in attempts to hypothesize MOAs (for endpoints without a well-established MOA) and to phenotypically anchor toxicogenomic and other mechanistic data both to toxicity endpoints and to available toxicogenomic data. This case study serves as an example of the steps that can be taken to develop a toxicological data source for a risk assessment, both in general and especially for risk assessments that include toxicogenomic data.
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