• 【基于核移植的牛心肌细胞重编程研究隔离。】 复制标题 收藏 收藏
    DOI:10.1089/clo.2006.8.150 复制DOI
    作者列表:Schwarzer M,Carnwath JW,Lucas-Hahn A,Lemme E,Kues WA,Wachsmann B,Haverich A,Martin U,Niemann H
    BACKGROUND & AIMS: :The goal of this study was to establish and validate a protocol for preparing bovine cardiomyocytes from slaughterhouse material for nuclear transfer experiments. The cardiomyocyte was selected because it is a terminally differentiated cell and strongly expresses a unique subset of genes which can be monitored during the reprogramming period. A total of 39 trials were conducted, and an optimized protocol was developed yielding individual contractile cardiomyocytes from 3-5-month-old bovine fetuses The basic protocol involves stabilization of bovine heart tissue for transportation from the slaughterhouse to the laboratory by perfusion with Custodiol. This was followed by an enzymatic dissociation with collagenase in calcium-free medium and yielded individual contractile rod-shaped cardiomyocytes. Subsequent addition of Ca2+ caused the cardiomyocytes to round up which was an essential pre-condition for drawing them into glass transfer pipettes for delivery into the perivitelline space and for efficient electrofusion with cytoplasts derived from in vitro matured bovine oocytes. The use of cardiomyocytes maintained at 37 degrees C in nuclear transfer, resulted in a significantly reduced proportion of blastocysts compared to adult fibroblasts (14.0% versus 32.7%). Storage of cardiomyocytes at 4 degrees C prior to nuclear transfer was not compatible with blastocyst development. It is expected that this system will be valuable for investigating the reprogramming of gene expression which occurs after somatic cell nuclear transfer.
    背景与目标: : 这项研究的目的是建立和验证从屠宰场材料中制备牛心肌细胞以进行核移植实验的协议。选择心肌细胞是因为它是终末分化的细胞,并且强烈表达可以在重编程期间监测的独特基因子集。总共进行了39项试验,并开发了一种优化的方案,从3-5个月大的牛胎儿中产生了单个收缩心肌细胞。基本方案涉及稳定牛心脏组织,以便通过灌注从屠宰场运输到实验室。保管二醇。随后在无钙培养基中与胶原酶酶解离,并产生单个收缩的杆状心肌细胞。随后添加Ca2会导致心肌细胞四舍五入,这是将其吸入玻璃转移移液管以输送到卵黄周围空间以及与来自体外成熟牛卵母细胞的细胞质进行有效电融合的必要前提。与成人成纤维细胞相比,在核转移中使用维持在37 ℃ 的心肌细胞导致胚泡的比例显著降低 (14.0% 对32.7%)。在核转移之前在4摄氏度下储存心肌细胞与胚泡发育不相容。预计该系统对于研究体细胞核移植后发生的基因表达的重编程将很有价值。
  • 【经皮给药颗粒加速的性能研究。】 复制标题 收藏 收藏
    DOI:10.1007/s11517-006-0050-4 复制DOI
    作者列表:Liu Y
    BACKGROUND & AIMS: :We have proposed a transdermal biolistic method to accelerate a powder formulation of drugs to penetrate human skin for the treatment of a range of diseases. One of the key issues for designing and evaluating transdermal biolistic system is ensuing that the powder drugs are delivered into the skin with a controllable velocity range and spatial distribution. The aerodynamics of supersonic nozzles and performance of the delivery system were initially studied, mainly analytically and experimentally. In this paper, computational fluid dynamics is utilized to characterize two existing prototype devices, in order to further investigate the transient gas and particle dynamics in their supersonic nozzles. To validate the implemented numerical approach, calculated pressure histories, two-dimensional flow structures and particle velocity distributions are made and compared with the reported experimental measurements. The key features of gas dynamics, gas-particle interaction and performance of the prototype transdermal biolistics are discussed and interpreted.
    背景与目标: : 我们提出了一种经皮生物注射方法,以加速药物的粉末制剂渗透人体皮肤以治疗一系列疾病。设计和评估透皮生物成像系统的关键问题之一是,将粉末药物以可控的速度范围和空间分布输送到皮肤中。初步研究了超音速喷嘴的空气动力学和输送系统的性能,主要是通过分析和实验进行了研究。本文利用计算流体动力学来表征两个现有的原型设备,以便进一步研究其超音速喷嘴中的瞬态气体和颗粒动力学。为了验证所实施的数值方法,计算了压力历史,二维流动结构和颗粒速度分布,并与报告的实验测量值进行了比较。讨论并解释了气体动力学,气体-颗粒相互作用和原型透皮生物技术性能的关键特征。
  • 【美国黑人和尼日利亚儿童的恶性肿瘤: 一项比较研究。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Olisa EG,Chandra R,Jackson MA,Kennedy J,Williams AO
    BACKGROUND & AIMS: :Results of a study on the relative frequencies of tumors in American black and Nigerian children were compared with data from the Childhood Cancer Registries in Manchester, United Kingdom, and Kampala, Uganda. The American black child living in Washington, D.C. and the Caucasian child living in Manchester had similar high frequencies for leukemia and glioma, whereas the incidence of lymphoma and retinoblastoma was low. African children living in Nigeria or Uganda had the opposite frequency patterns. These differences in frequencies of tumors between two ethnologically related population groups, American black and Nigerian, suggested the influence of environmental factors in the etiology of these tumors, even though exposure to environmental carcinogens was short. The rarity of Ewing's sarcoma and testicular tumors in American black and Nigerian children suggested a genetic influence.
    背景与目标: : 将美国黑人和尼日利亚儿童肿瘤相对频率的研究结果与英国曼彻斯特和乌干达坎帕拉的儿童癌症登记处的数据进行了比较。居住在华盛顿特区的美国黑人儿童和居住在曼彻斯特的高加索儿童患白血病和神经胶质瘤的频率相似,而淋巴瘤和视网膜母细胞瘤的发生率较低。生活在尼日利亚或乌干达的非洲儿童的频率模式相反。尽管暴露于环境致癌物的时间很短,但两个与种族相关的人群 (美国黑人和尼日利亚人) 之间的肿瘤频率差异表明环境因素对这些肿瘤的病因的影响。美国黑人和尼日利亚儿童尤因肉瘤和睾丸肿瘤的稀有性表明了遗传影响。
  • 【罗非考昔是细胞色素P450 1A2的有效抑制剂: 在健康受试者中使用替扎尼定和咖啡因进行的研究。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2125.2006.02653.x 复制DOI
    作者列表:Backman JT,Karjalainen MJ,Neuvonen M,Laitila J,Neuvonen PJ
    BACKGROUND & AIMS: AIMS:Case reports suggest an interaction between rofecoxib and the CYP1A2 substrate tizanidine. Our objectives were to explore the extent and mechanism of this possible interaction and to determine the CYP1A2 inhibitory potency of rofecoxib. METHODS:In a randomized, double-blind, two-phase cross-over study, nine healthy subjects took 25 mg rofecoxib or placebo daily for 4 days and, on day 4, each ingested 4 mg tizanidine. Plasma concentrations and the urinary excretion of tizanidine, its metabolites (M) and rofecoxib, and pharmacodynamic variables were measured up to 24 h. On day 3, a caffeine test was performed to estimate CYP1A2 activity. RESULTS:Rofecoxib increased the area under the plasma concentration-time curve (AUC(0-infinity)) of tizanidine by 13.6-fold [95% confidence interval (CI) 8.0, 15.6; P < 0.001), peak plasma concentration (C(max)) by 6.1-fold (4.8, 7.3; P < 0.001) and elimination half-life (t(1/2)) from 1.6 to 3.0 h (P < 0.001). Consequently, rofecoxib markedly increased the blood pressure-lowering and sedative effects of tizanidine (P < 0.05). Rofecoxib increased several fold the tizanidine/M-3 and tizanidine/M-4 ratios in plasma and urine and the tizanidine/M-5, tizanidine/M-9 and tizanidine/M-10 ratios in urine (P < 0.05). In addition, it increased the plasma caffeine/paraxanthine ratio by 2.4-fold (95% CI 1.4, 3.4; P = 0.008) and this ratio correlated with the tizanidine/metabolite ratios. Finally, the AUC(0-25) of rofecoxib correlated with the placebo phase caffeine/paraxanthine ratio (r = 0.80, P = 0.01). CONCLUSIONS:Rofecoxib is a potent inhibitor of CYP1A2 and it greatly increases the plasma concentrations and adverse effects of tizanidine. The findings suggest that rofecoxib itself is also metabolized by CYP1A2, raising concerns about interactions between rofecoxib and other CYP1A2 substrate and inhibitor drugs.
    背景与目标:
  • 【通过临床分离株新基因的鉴定和分布研究,揭示了铜绿假单胞菌广泛的基因组可塑性。】 复制标题 收藏 收藏
    DOI:10.1128/IAI.00546-06 复制DOI
    作者列表:Shen K,Sayeed S,Antalis P,Gladitz J,Ahmed A,Dice B,Janto B,Dopico R,Keefe R,Hayes J,Johnson S,Yu S,Ehrlich N,Jocz J,Kropp L,Wong R,Wadowsky RM,Slifkin M,Preston RA,Erdos G,Post JC,Ehrlich GD,Hu FZ
    BACKGROUND & AIMS: :The distributed genome hypothesis (DGH) states that each strain within a bacterial species receives a unique distribution of genes from a population-based supragenome that is many times larger than the genome of any given strain. The observations that natural infecting populations are often polyclonal and that most chronic bacterial pathogens have highly developed mechanisms for horizontal gene transfer suggested the DGH and provided the means and the mechanisms to explain how chronic infections persist in the face of a mammalian host's adaptive defense mechanisms. Having previously established the validity of the DGH for obligate pathogens, we wished to evaluate its applicability to an opportunistic bacterial pathogen. This was accomplished by construction and analysis of a highly redundant pooled genomic library containing approximately 216,000 functional clones that was constructed from 12 low-passage clinical isolates of Pseudomonas aeruginosa, 6 otorrheic isolates and 6 from other body sites. Sequence analysis of 3,214 randomly picked clones (mean insert size, approximately 1.4 kb) from this library demonstrated that 348 (10.8%) of the clones were unique with respect to all genomic sequences of the P. aeruginosa prototype strain, PAO1. Hypothetical translations of the open reading frames within these unique sequences demonstrated protein homologies to a number of bacterial virulence factors and other proteins not previously identified in P. aeruginosa. PCR and reverse transcription-PCR-based assays were performed to analyze the distribution and expression patterns of a 70-open reading frame subset of these sequences among 11 of the clinical strains. These sequences were unevenly distributed among the clinical isolates, with nearly half (34/70) of the novel sequences being present in only one or two of the individual strains. Expression profiling revealed that a vast majority of these sequences are expressed, strongly suggesting they encode functional proteins.
    背景与目标: : 分布式基因组假说 (DGH) 指出,细菌物种中的每个菌株都从基于群体的上基因组接收到独特的基因分布,该基因分布比任何给定菌株的基因组大很多倍。观察到自然感染种群通常是多克隆的,并且大多数慢性细菌病原体具有高度发达的水平基因转移机制,这表明DGH并提供了手段和机制来解释慢性感染如何在哺乳动物宿主的适应性防御机制中持续存在。先前已经确定了DGH对专性病原体的有效性,我们希望评估其对机会性细菌病原体的适用性。这是通过构建和分析包含约216,000个功能克隆的高度冗余的合并基因组文库来实现的,所述基因组文库是从铜绿假单胞菌的12个低传代临床分离株、6个耳鼻喉科分离株和6个来自其他身体位点构建的。对从该文库中随机挑选的3,214个克隆 (平均插入大小,约1.4 kb) 的序列分析表明,对于铜绿假单胞菌原型菌株pao1的所有基因组序列,348 (10.8%) 的克隆是独特的。这些独特序列中开放阅读框的假设翻译证明了蛋白质与许多细菌毒力因子和其他以前在铜绿假单胞菌中未鉴定的蛋白质的同源性。进行了PCR和基于逆转录PCR的检测,以分析11种临床菌株中这些序列的70个开放阅读框子集的分布和表达模式。这些序列在临床分离株中分布不均匀,近一半 (34/70) 新序列仅存在于单个菌株中的一个或两个中。表达谱分析显示,这些序列中的绝大多数都被表达,这强烈表明它们编码功能蛋白。
  • 【使用口译员的跨文化访谈研究: 系统的文献综述。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2648.2006.03963.x 复制DOI
    作者列表:Wallin AM,Ahlström G
    BACKGROUND & AIMS: AIM:This paper reviews how the interpreter's role is described in empirically based, qualitative cross-cultural interview studies and how trustworthiness is determined. BACKGROUND:Increased immigration during the past decades has created a multiethnic society in many countries. This development poses a challenge to healthcare staff, in that they need to understand how people from different cultures experience health and illness. One way to assess immigrants' experiences is through cross-cultural interview studies, involving an interpreter. Thorough knowledge of the interpreter's role is needed in order to increase the trustworthiness of this kind of nursing research. METHOD:Literature searches were conducted from October to November 2004 using PubMed, CINAHL, Psycinfo, Sociological abstract, Your Journals@ovid, and Eric databases. Qualitative interview studies written in English and performed with an interpreter were included. The Matrix Method was used to review the literature. FINDINGS:In almost all of the 13 relevant papers found, the role of the interpreter(s) in the research process was only sparsely described. In addition, all studies except one employed different techniques to established trustworthiness. The most common techniques were prolonged engagement, member check or triangulation, the latter performed either on the data, investigators or methods. CONCLUSION:Methodological issues with respect to interpreters have received only limited attention in cross-cultural interview studies. Researchers in the field of nursing need to consider (1) the interpreter's role/involvement in the research process; (2) the interpreter's competence and the style of interpreting; (3) the interpreter's impact on the findings. This information is a prerequisite when trying to determine the trustworthiness of a cross-cultural study.
    背景与目标:
  • 【CROPPER: 用于跨平台和跨物种汇编研究的metagene creator资源。】 复制标题 收藏 收藏
    DOI:10.1186/1471-2105-7-418 复制DOI
    作者列表:Paananen J,Storvik M,Wong G
    BACKGROUND & AIMS: BACKGROUND:Current genomic research methods provide researchers with enormous amounts of data. Combining data from different high-throughput research technologies commonly available in biological databases can lead to novel findings and increase research efficiency. However, combining data from different heterogeneous sources is often a very arduous task. These sources can be different microarray technology platforms, genomic databases, or experiments performed on various species. Our aim was to develop a software program that could facilitate the combining of data from heterogeneous sources, and thus allow researchers to perform genomic cross-platform/cross-species studies and to use existing experimental data for compendium studies. RESULTS:We have developed a web-based software resource, called CROPPER that uses the latest genomic information concerning different data identifiers and orthologous genes from the Ensembl database. CROPPER can be used to combine genomic data from different heterogeneous sources, allowing researchers to perform cross-platform/cross-species compendium studies without the need for complex computational tools or the requirement of setting up one's own in-house database. We also present an example of a simple cross-platform/cross-species compendium study based on publicly available Parkinson's disease data derived from different sources. CONCLUSION:CROPPER is a user-friendly and freely available web-based software resource that can be successfully used for cross-species/cross-platform compendium studies.
    背景与目标:
  • 【残基Leu 93和Asp 96在细菌视紫红质光周期中独立起作用: 对leu 93->Ala,Asp 96->Asn双突变体的研究。】 复制标题 收藏 收藏
    DOI:10.1016/S0006-3495(96)79803-X 复制DOI
    作者列表:Delaney JK,Subramaniam S
    BACKGROUND & AIMS: Previous mutagenesis studies with bacteriorhodopsin have shown that reprotonation of the Schiff's base is the rate-limiting step in the photocycle of the D96N mutant, whereas retinal re-isomerization and return of the protein to the initial state constitute the rate-limiting events in the photocycle of the L93A mutant. Thus, in the D96N mutant, decay of the M intermediate is slowed down by more than 100-fold at pH 7. In the L93A mutant, decay of the O intermediate is slowed down by 250-fold. We report here that in the L93A, D96N double mutant, decay of the M intermediate, as well as the formation and decay of the O intermediate, are slowed down dramatically. The photocycle is completed by the decay of a long-lived O intermediate, as in the L93A mutant. The decay of the M and O intermediates in the double mutant parallels the behavior seen in the single mutants over a wide temperature and pH range, arguing that the observed independence is an intrinsic property of the mutant. The slow decay of the M and O intermediates can be selectively and independently reversed under conditions identical to those used for the corresponding intermediates in the D96N and L93A single mutants. Because the effects of the two individual mutations are preserved in the double mutant and can be independently reversed, we conclude that residues Asp 96 and Leu 93 act independently and at different stages of the bacteriorhodopsin photocycle. These results also show that formation of the O intermediate only requires protonation of the Schiff's base and is independent of the protonation of Asp 96 from the aqueous medium.

    背景与目标: 先前对细菌视紫红质的诱变研究表明,席夫碱的再质子化是D96N突变体光循环中的限速步骤,而视网膜再异构化和蛋白质返回到初始状态则构成了光循环中的限速事件。L93A突变体。因此,在D96N突变体中,M中间体的衰变在ph7下减慢了100倍以上。在L93A突变体中,O中间体的衰变减慢250倍。我们在这里报告说,在L93A,D96N双突变体中,M中间体的衰变以及O中间体的形成和衰变显着减慢。像L93A突变体一样,通过长寿命O中间体的衰变来完成光循环。双突变体中M和O中间体的衰变与在宽温度和pH范围内单个突变体中看到的行为相似,认为观察到的独立性是突变体的内在特性。M和O中间体的缓慢衰变可以在与D96N和L93A单个突变体中相应中间体所使用的条件相同的条件下选择性地和独立地逆转。由于两个个体突变的作用保留在双突变体中并且可以独立逆转,因此我们得出结论,残基Asp 96和Leu 93独立且在细菌视紫红质光循环的不同阶段起作用。这些结果还表明,O中间体的形成仅需要席夫碱的质子化,并且与水性介质中Asp 96的质子化无关。
  • 【神经放射学亚专业专家对脑ct成像研究的重新解释的质量结果。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Jordan MJ,Lightfoote JB,Jordan JE
    BACKGROUND & AIMS: PURPOSE:To determine the clinical importance and relative value of reinterpreting brain CT imaging studies by subspecialty experts regarding changes in clinical management. METHODS:Computerized records were queried at two institutions during the years 2002-2003 for both primary interpretation by board-certified nonneuroradiologists and secondary interpretation by three neuroradiologists. A total of 1,081 cases were reviewed. Each case was initially interpreted as an emergent or urgent study. The reinterpreted studies were scored as concordant or discordant by the subspecialty experts. The discordant studies were then categorized as a "major discordance" if there was a change in clinical management, or as a "minor discordance" if there was no impact or change in clinical management. RESULTS:Of the 1,081 studies reviewed, 14 studies were identified as discordant (1.3%). Of those discordant studies, four were categorized as major discrepancies necessitating a change in clinical management (0.4 %). Ten were categorized as minor discrepancies (0.9%). There were no permanent adverse outcomes with respect to morbidity and mortality as a result of any discrepancy. CONCLUSION:The vast majority of interpreted head CT cases read by board-certified general radiologists do not result in discordant interpretations as verified by subspecialty experts. Discordant interpretations did not result in changes in clinical management in most cases. Double reading of head CTs by subspecialty experts appears to be an inefficient method of substantially improving imaging health quality outcomes.
    背景与目标:
  • 【在急诊科新发癫痫发作患者中进行实验室研究的实用性。】 复制标题 收藏 收藏
    DOI:10.1016/s0196-0644(05)82337-6 复制DOI
    作者列表:Turnbull TL,Vanden Hoek TL,Howes DS,Eisner RF
    BACKGROUND & AIMS: :Extensive laboratory testing is often performed in the emergency department evaluation of the new-onset seizure patient. To determine the utility of such testing, a prospective study of patients with a new-onset seizure presenting to the ED of an inner-city, university-affiliated teaching hospital was done. One hundred thirty-six patients were entered into the study between October 1984 and January 1988. All patients had uniform data collection performed. Pertinent historical information and physical examination findings were recorded on a standardized form before laboratory abnormality was a sole or contributory cause of the seizure disorder. These included four patients with hypoglycemia, four with hyperglycemia, two with hypocalcemia, and one with hypomagnesemia. Only two cases (hypoglycemia) were not suspected on the basis of findings on the history or physical examination. In ED patients, the incidence of a new-onset seizure due to a correctable metabolic disturbance is low. We conclude that, with the exception of the serum glucose, the extensive ED laboratory workup often done for the evaluation of a new-onset seizure is unnecessary. Further test ordering should be directed by the medical history and physical examination.
    背景与目标: : 在急诊科对新发癫痫患者的评估中,经常进行广泛的实验室测试。为了确定这种测试的实用性,对向市中心大学附属教学医院的ED呈递的新发癫痫发作患者进行了前瞻性研究。在1984年10月和1988年1月之间,有136名患者进入了研究。所有患者均进行了统一的数据收集。在实验室异常是癫痫发作的唯一或促成原因之前,将相关的历史信息和体格检查结果记录在标准化表格上。其中包括4名低血糖患者,4名高血糖患者,2名低钙血症患者和1名低镁血症患者。根据病史或体格检查发现,仅怀疑有2例 (低血糖)。在ED患者中,由于可纠正的代谢紊乱而引起的新发癫痫发作的发生率较低。我们得出的结论是,除血清葡萄糖外,通常不需要进行广泛的ED实验室检查以评估新发癫痫发作。进一步的检查顺序应由病史和体格检查指示。
  • 【地中海鱼类和贝类可食用部分的比较季节性固醇谱。】 复制标题 收藏 收藏
    DOI:10.3109/09637486.2012.749836 复制DOI
    作者列表:Ozyurt G,Kuley E,Etyemez M,Ozoğul F
    BACKGROUND & AIMS: :The effect of different seasons on sterol content of seafoods was investigated. There were four sterols (cholesterol, sitosterol, desmosterol and stigmasterol) identified, with cholesterol being the predominant sterol. Stigmasterol was a minor component in fish muscle, whilst sitosterol was one of the main phytosterols found in fish muscle. Cholesterol content of fish consisted of 38-100% of total sterols in fish and 54-80% of total sterols in shellfish. The highest cholesterol content of fish muscle was found in summer and the lowest in autumn, whereas season did not have any effect on cholesterol level of green tiger prawn and speckled shrimp. Total sterol content of fish muscle ranged from 49 to 110 mg/100 g, although the range of total sterols in shrimp muscle was between 62 and 91 mg/100 g. The result of the study showed that total sterols in fish were generally found at lower levels in winter compared with other seasons.
    背景与目标: : 研究了不同季节对海鲜中固醇含量的影响。鉴定出四种固醇 (胆固醇,谷甾醇,去甾醇和豆甾醇),其中胆固醇是主要的固醇。豆甾醇是鱼类肌肉中的次要成分,而谷甾醇是鱼类肌肉中发现的主要植物甾醇之一。鱼的胆固醇含量由鱼中38-100% 的总甾醇和贝类中54-80% 的总甾醇组成。夏季发现鱼肌肉中胆固醇含量最高,秋季最低,而季节对绿虎虾和斑点虾的胆固醇水平没有任何影响。鱼肌肉的总固醇含量范围为49至110 mg/100g,尽管虾肌肉中的总固醇含量范围为62至91 mg/100g。研究结果表明,与其他季节相比,冬季鱼中的总固醇含量通常较低。
  • 【在假定的眼结核患者中,通过正电子发射断层扫描/计算机断层扫描 (PET/CT) 研究全身摄取18-fdg的模式。】 复制标题 收藏 收藏
    DOI:10.3109/09273948.2012.697596 复制DOI
    作者列表:Mehta S
    BACKGROUND & AIMS: AIM:To report the patterns and sites of 18-FDG uptake in patients of presumed ocular tuberculosis. MATERIALS AND METHODS:The clinical and investigational findings of 11 patients were reviewed retrospectively. These included 6 males and 5 females with a mean age of 46.2 years. 21 eyes were included in the data analysis. Clinical presentations include 15 eyes with anterior uveitis, 2 eyes with retinal vasculitis, 2 eyes with panuveitis and 2 eyes with multifocal choroidopathy. RESULTS:Two distinct patterns of systemic uptake emerged. Pattern 1: No detectable systemic uptake (4 patients). Pattern 2: Detectable systemic uptake. a. Chest disease only (2 patients). b. Disseminated pattern, uptake seen at multiple sites (4 patients). c. Extrapulmonary only (1 patient). CONCLUSIONS:Ocular tuberculosis may often be part of a wider disseminated disease.
    背景与目标:
  • 【从头进行转录组测序和比较分析,以发现与圆线虫卵巢成熟有关的基因。】 复制标题 收藏 收藏
    DOI:10.1016/j.cbd.2017.05.002 复制DOI
    作者列表:Jia Z,Wang Q,Wu K,Wei Z,Zhou Z,Liu X
    BACKGROUND & AIMS: :Strongylocentrotus nudus is an edible sea urchin, mainly harvested in China. Correlation studies indicated that S. nudus with larger diameter have a prolonged marketing time and better palatability owing to their precocious gonads and extended maturation process. However, the molecular mechanism underlying this phenomenon is still unknown. Here, transcriptome sequencing was applied to study the ovaries of adult S. nudus with different shell diameters to explore the possible mechanism. In this study, four independent cDNA libraries were constructed, including two from the big size urchins and two from the small ones using a HiSeq™2500 platform. A total of 88,581 unigenes were acquired with a mean length of 1354bp, of which 66,331 (74.88%) unigenes could be annotated using six major publicly available databases. Comparative analysis revealed that 353 unigenes were differentially expressed (with log2(ratio)≥1, FDR≤0.001) between the two groups. Of these, 20 differentially expressed genes (DEGs) were selected to confirm the accuracy of RNA-seq data by quantitative real-time RT-PCR. Furthermore, gene ontology and KEGG pathway enrichment analyses were performed to find the putative genes and pathways related to ovarian maturity. Eight unigenes were identified as significant DEGs involved in reproduction related pathways; these included Mos, Cdc20, Rec8, YP30, cytochrome P450 2U1, ovoperoxidase, proteoliaisin, and rendezvin. Our research fills the gap in the studies on the S. nudus ovaries using transcriptome analysis.
    背景与目标: : Strongylocentrotus nudus是一种可食用的海胆,主要在中国收获。相关研究表明,直径较大的S. nudus由于其早熟的性腺和成熟过程的延长,具有延长的销售时间和更好的适口性。然而,这种现象背后的分子机制仍然未知。在此,将转录组测序用于研究具有不同壳直径的成年S. nudus的卵巢,以探讨其可能的机制。在这项研究中,使用HiSeq构建了四个独立的cDNA文库,其中两个来自大海胆,两个来自小海胆。™2500平台。总共获得了88,581个单基因,平均长度为1354bp,其中66,331个 (74.88% 个) 单基因可以使用六个主要的公开数据库进行注释。比较分析显示,两组之间353单基因差异表达 (log2 (比率) ≥ 1,fdr ≤ 0.001)。其中,选择了20个差异表达基因 (deg),以通过定量实时rt-pcr确认RNA-seq数据的准确性。此外,还进行了基因本体论和KEGG途径富集分析,以找到与卵巢成熟度相关的推定基因和途径。八个单基因被鉴定为参与生殖相关途径的重要deg; 这些包括Mos,Cdc20,Rec8,YP30,细胞色素P450 2U1,卵巢过氧化物酶,蛋白毒素和rendezvin。我们的研究填补了使用转录组分析对卵巢S. nudus卵巢的研究的空白。
  • 【三种厌氧菌识别系统的比较评估。】 复制标题 收藏 收藏
    DOI:10.1128/JCM.22.1.52-55.1985 复制DOI
    作者列表:Murray PR,Weber CJ,Niles AC
    BACKGROUND & AIMS: :The accuracy of two new 4-h identification systems for anaerobes, the AN-IDENT (Analytab Products, Plainview, N.Y.) and the RapID ANA (Innovative Diagnostic Systems, Inc., Atlanta, Ga.) was compared with that of the API 20A system (Analytab Products). A total of 132 clinical isolates were tested in each of the three systems. The overall accuracies at the genus and species level for the three systems were: API 20A, 68.9 and 56.8%, respectively; AN-IDENT, 90.2 and 73.5%; and RapID ANA, 93.9 and 81.8%. Improved identification of anaerobes with the AN-IDENT and the RapID ANA systems was observed for isolates of the genus Fusobacterium, Clostridium species other than Clostridium perfringens, non-spore-forming bacilli, and isolates of the genus Peptostreptococcus. Reproducibility studies demonstrated that the results of the individual test reactions in all three identification systems were reproducible when the interpretive guidelines of the manufacturer were followed precisely.
    背景与目标: : 将两种新的4小时厌氧菌识别系统的准确性,即AN-IDENT (Analytab Products,纽约州Plainview) 和RapID ANA (Innovative Diagnostic systems,inc.,乔治亚州亚特兰大) 与API 20A系统 (Analytab产品)。在这三个系统中的每个系统中总共测试了132个临床分离株。这三个系统在属和种级别的总体精度分别为: API 20A,68.9和56.8%; A-IDENT,90.2和73.5%; 和快速ANA,93.9和81.8%。对于梭菌属,除产气荚膜梭状芽孢杆菌以外的梭状芽孢杆菌属,非孢子形成杆菌和消化链球菌属的分离株,观察到an-ident和快速ANA系统对厌氧菌的鉴定得到了改善。可重复性研究表明,当精确遵循制造商的解释准则时,所有三个识别系统中单个测试反应的结果都是可重现的。
  • 【验证淋巴结清扫术在子宫内膜癌中的治疗作用的随机对照试验与比较队列研究。】 复制标题 收藏 收藏
    DOI:10.1007/s10147-012-0499-0 复制DOI
    作者列表:Todo Y,Sakuragi N
    BACKGROUND & AIMS: :A consensus regarding the therapeutic role of lymphadenectomy in endometrial cancer has not been reached because of conflicting negative results of randomized controlled trials and positive results of a cohort study. Since the effects of new treatments tend to be overestimated in observational studies, positive results of an observational study should be validated by a future trial. However, special difficulties are presented in randomized controlled trials in surgery. External validity is important for guaranteeing the reliability of a result of the trial. Physicians' recruitment of eligible patients into a trial depends on the confidence of those physicians for a surgical procedure, workplace environment and feelings of personal responsibility relevant to patients' risk of recurrence. When two surgical procedures are compared in a randomized controlled trial, technical quality control may be reduced in the complicated surgery group due to experienced surgeons' non-participation. It is highly possible that the recruitment issue is a threat to external validity. Therefore, a randomized controlled trial may not be the best format for demonstrating the full benefits of complicated surgery. Multiple studies have demonstrated that the results of well-designed observational studies can be reliable and are comparable with those of randomized controlled trials. Journal editors and funding sources are requested to become more generous with observational studies, especially prospective cohort studies.
    背景与目标: : 由于随机对照试验的阴性结果与队列研究的阳性结果相互矛盾,因此尚未就淋巴结清扫术在子宫内膜癌中的治疗作用达成共识。由于在观察性研究中往往高估了新疗法的效果,因此观察性研究的阳性结果应通过未来的试验来验证。然而,在外科手术的随机对照试验中存在特殊困难。外部有效性对于保证试验结果的可靠性很重要。医生是否招募合格的患者参加试验取决于这些医生对外科手术,工作场所环境以及与患者复发风险相关的个人责任感的信心。在随机对照试验中比较两种手术方法时,由于经验丰富的外科医生不参与,复杂手术组的技术质量控制可能会降低。招聘问题很有可能威胁到外部有效性。因此,随机对照试验可能不是证明复杂手术的全部益处的最佳形式。多项研究表明,精心设计的观察性研究的结果是可靠的,并且与随机对照试验的结果相当。要求期刊编辑和资金来源对观察性研究,尤其是前瞻性队列研究更加慷慨。

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