• 【在成年的山毛榉树下,长期熏蒸成双倍的环境臭氧浓度,其外生菌根真菌群落的变化和细根数的增加。】 复制标题 收藏 收藏
    DOI:10.1055/s-2006-924489 复制DOI
    作者列表:Grebenc T,Kraigher H
    BACKGROUND & AIMS: :Forest soils are an important but under-studied part of forest ecosystems. The effects of O(3) on below-ground processes in a mature forest have only received limited attention so far. In our study, we have analysed the community of ectomycorrhizal fungi and beech fine root dynamics over two growing seasons (2003 - 2004) in a 70-year old mixed spruce-beech forest stand, in which two groups of five adult beech trees were either fumigated by 2 x ambient ozone concentration or used as control. The main difference between previous studies and our approach was that previous studies were performed on seedlings in pot experiments or in closed or open top chambers, and not IN SITU, in a mature forest stand. Although beech is a relatively unresponsive species to tropospheric O(3), we found a pronounced effect of 2 x O(3) on the number of vital ectomycorrhizal root tips and non-turgescent fine roots. Both categories of roots were significantly increased when compared to controls in two consecutive years at each sampling event. The number of types of ectomycorrhizae and species richness increased in 2004, but not in the extremely dry year 2003. We hypothesised that the observed changes might be an expression of a transitional state in below-ground succession of niches caused by an O(3) induced effect on carbon allocation to roots and the rhizosphere. We have detected changes in ectomycorrhizal species level, however Shannon-Weavers species diversity index and percentage of types of ectomycorrhizae did not change significantly in any sampling year thus indicating our results cannot be unequivocally explained by summer drought in year 2003 or by O(3) exposure alone.
    背景与目标: 森林土壤是森林生态系统中重要但未被充分研究的部分。迄今为止,O(3)对成熟森林地下过程的影响仅受到有限的关注。在我们的研究中,我们分析了一个70年历史的云杉-山毛榉林分两个生长季节(2003年至2004年)的外生菌根真菌和山毛榉细根动态,其中两组分别是五棵成年的山毛榉木用2倍的环境臭氧浓度熏蒸或用作对照。以前的研究与我们的方法之间的主要区别是,以前的研究是在盆栽实验中或在密闭或敞开的顶室中对幼苗进行的,而不是在成熟林分中的IN SITU中进行的。尽管山毛榉对对流层O(3)的响应相对较弱,但我们发现2 x O(3)对活着的外生菌根根尖和非浑浊的细根的数量有明显的影响。与每个采样事件连续两年的对照相比,这两种类别的根均显着增加。 2004年外生菌根类型的种类和物种丰富度有所增加,但在极度干旱的2003年却没有。我们假设观察到的变化可能是由O(3)引起的地下生态位过渡状态的一种表达。诱导对根和根际碳分配的影响。我们已经检测到外生菌根物种水平的变化,但是香农-韦弗物种多样性指数和外生菌根类型的百分比在任何采样年中都没有显着变化,因此表明我们的结果不能被2003年夏季干旱或O(3)明确解释。独自暴露。
  • 【罕见的母体mRNA编码调控蛋白,这些蛋白控制着海胆胚胎中谱系特异性基因的表达。】 复制标题 收藏 收藏
    DOI:10.1073/pnas.87.20.7953 复制DOI
    作者列表:Cutting AE,Höög C,Calzone FJ,Britten RJ,Davidson EH
    BACKGROUND & AIMS: :The prevalence of mRNAs coding for the sea urchin embryo regulatory factors P3A1 and P3A2 was measured by single-strand probe excess solution hybridization. P3A1 and P3A2 are not homologous proteins, though they both bind specifically to a particular cis-regulatory sequence. Interaction at this target site is known to be required for lineage-specific expression of an aboral ectoderm-specific gene and probably for several other genes as well. Genome blot hybridizations show that both factors are encoded by single-copy genes. Maternal mRNAs for both factors are present at less than 10(3) molecules per egg, which places them in the rare mRNA class. During development to the mesenchyme blastula stage, the amount of P3A1 mRNA (per embryo) increases severalfold while that of P3A2 remains approximately constant. Specification of the aboral ectoderm founder cells and of their initial patterns of gene expression must occur during early to mid-cleavage stage. Therefore, the regulatory proteins needed for this process must be produced by this stage. We show that the quantities of the P3A proteins that can be synthesized from the numbers of mRNA molecules present in the large blastomeres of the early embryo are sufficient to be functional, because these proteins will be accumulated in the nuclei. Thus maternal P3A1 or P3A2 proteins asre not required, nor were these detected in earlier studies. Furthermore, differential spatial (as well as temporal) distribution of both of these newly synthesized factor species could result from the unequal cleavage pattern utilized in the sea urchin egg.
    背景与目标: :通过单链探针过量溶液杂交测量编码海胆胚胎调节因子P3A1和P3A2的mRNA的发生率。尽管P3A1和P3A2都与特定的顺式调控序列特异性结合,但它们不是同源蛋白。已知该靶标位点的相互作用是特定于宗族的外胚层特异性基因的谱系表达所必需的,并且可能还需要其他几个基因。基因组印迹杂交显示这两个因子均由单拷贝基因编码。每个鸡蛋的母体mRNA均少于10(3)个分子,这使它们处于罕见的mRNA类中。在发育到间充质囊阶段期间,P3A1 mRNA(每个胚胎)的数量增加了几倍,而P3A2的数量则保持大致恒定。胎盘外胚层基础细胞及其基因表达的初始模式的规范必须在卵裂早期至中期进行。因此,必须在该阶段生产该过程所需的调节蛋白。我们表明,可以从早期胚胎的大型卵裂球中存在的mRNA分子数量合成的P3A蛋白数量足以发挥功能,因为这些蛋白将积聚在细胞核中。因此,不需要母体P3A1或P3A2蛋白,也不需要在早期研究中检测到这些蛋白。此外,这两种新合成的因子物种在空间(以及时间)上的差异分布可能是由于海胆卵中使用的不均等卵裂模式造成的。
  • 【田纳西州东部怀孕少女的生殖道沙眼衣原体感染:一项为期7年的病例对照研究。】 复制标题 收藏 收藏
    DOI:10.1016/s1083-3188(97)70060-3 复制DOI
    作者列表:Chokephaibulkit K,Patamasucon P,List M,Moore B,Rodriguez H
    BACKGROUND & AIMS: STUDY OBJECTIVE:To examine the prevalence, symptomatology, risk factors, and other infections associated with urogenital chlamydial infection in pregnant teenagers. DESIGN:Retrospective case-control study by medical record review. SETTING:Prenatal care clinic for adolescents at University of Tennessee Medical Center, Knoxville, Tennessee. PARTICIPANTS:Pregnant adolescents younger than 19 years of age who were diagnosed with chlamydial infection on the first prenatal visit from 1988 to 1994 were studied. Pregnant adolescents of similar age and socioeconomic background who came in the same day for the first prenatal visit, but were not infected, made up the control group. INTERVENTION:Routine prenatal questionnaires regarding personal and medical histories, and routine prenatal screening, including pelvic examination with Papanicolaou (PAP) smear and laboratory investigations for common genital infections and sexual transmitted disease (STDs), were obtained. MAIN OUTCOME MEASURES:Analyzed the prevalence of chlamydial infection and compared the infected group to the control group with regard to race, behavioral factors, symptoms, prenatal screening results, other concurrent genital infections, and histories of STDs. RESULTS:Of a total population of 596 pregnant teenagers, 67 (11.24%) were infected with Chlamydia trachomatis. In multivariate analysis, black race (odds ratio [OR] = 4.01; 95% confidence interval [CI] = 1.74-9.23; p = 0.001) and greater gestational age at first prenatal visit (OR = 1.11; 95% CI = 1.04-1.18; p = 0.001) were independently associated with chlamydial infection. Age, marital status, number of pregnancies, smoking, alcohol abuse, drug abuse, age at first intercourse, and multiple sex partners were not associated with the infection. Likewise, the symptom of vaginal discharge (a complaint of > 70% in each group), other genital co-infections (found > 50% in each group, mainly candidiasis and bacterial vaginosis), abnormal PAP smears (found > 60% in each group) and histories of STDs or previous chlamydial infection were not significantly different between case and control groups. Human papillomavirus infection, trichomonal infection, and dysplasia or atypia were found more often in patients infected with chlamydia, but were not statistically significant. CONCLUSION:Pregnant adolescents in east Tennessee were at risk for chlamydial infection as well as for other genital infections and abnormal PAP smears. Routine prenatal chlamydial screening is warranted because of a lack of specific symptoms.
    背景与目标: 目的:研究孕妇青少年泌尿生殖道衣原体感染的患病率,症状,危险因素和其他感染情况。
    设计:回顾性病例对照研究,病历审查。
    地点:田纳西州诺克斯维尔市田纳西大学医学中心的青少年产前保健诊所。
    研究对象:1988年至1994年第一次产前检查时被诊断患有衣原体感染的19岁以下的青少年。年龄相同,社会经济背景相似的怀孕青少年在同一天进行第一次产前检查,但未感染,组成了对照组。
    干预措施:获得有关个人和医学史的常规产前问卷,以及常规的产前筛查,包括用帕潘尼古拉(PAP)涂片进行盆腔检查以及常见生殖器感染和性传播疾病(STD)的实验室检查。
    主要观察指标:分析衣原体感染的发生率,并比较种族,行为因素,症状,产前筛查结果,其他并发生殖器感染和性病史,比较感染者与对照组。
    结果:在596名怀孕的青少年总数中,有67名(11.24%)感染了沙眼衣原体。在多变量分析中,黑人种族(赔率[OR] = 4.01; 95%置信区间[CI] = 1.74-9.23; p = 0.001)和第一次产前检查时的胎龄较高(OR = 1.11; 95%CI = 1.04- 1.18; p = 0.001)与衣原体感染独立相关。年龄,婚姻状况,怀孕次数,吸烟,酗酒,药物滥用,初次性交年龄和多性伴侣均与感染无关。同样,白带的症状(每组的投诉> 70%),其他生殖器合并感染(每组的发现> 50%,主要是念珠菌病和细菌性阴道病),PAP涂片异常(每发的发现> 60%)病例组和对照组之间的性病史或以前的衣原体感染史无显着差异。感染衣原体的患者更常发现人乳头瘤病毒感染,滴虫感染和异型增生或异型性,但无统计学意义。
    结论:田纳西州东部的怀孕青少年有衣原体感染以及其他生殖器感染和PAP涂片异常的危险。由于缺乏特定症状,需要常规的产前衣原体筛查。
  • 【意大利北部某地区的综合废物管理:堆肥的生产和使用,以及堆肥,土壤和农作物的分析控制。】 复制标题 收藏 收藏
    DOI:10.1080/03601230600857031 复制DOI
    作者列表:Guerini G,Maffeis P,Allievi L,Gigliotti C
    BACKGROUND & AIMS: :Agricultural soils of two Italian maize farms were treated for five years with an industrially produced high-quality compost. Cattle manure and the usual mineral fertilizer were used for comparison purposes. The effects of the organic and mineral fertilizer treatments were studied by analyzing the compost and manure, cultured soils, and harvested material. The grain yield was also determined. Organic fertilization improved soil pH, CEC, content of organic matter and NPK. Soil respiration and N mineralization were found to be higher than in the purely mineral-treated soil. Plant K take-up was improved, whereas grain yield was not affected. It was confirmed that organic fertilization, particularly compost use, maintained and increased soil fertility. The study demonstrated the feasibility of using in loco analytical facilities to follow the entire recycling process-from waste to compost production-and the use of the final product in the field.
    背景与目标: :意大利的两个玉米农场的农业土壤用工业生产的高质量堆肥处理了五年。为了比较,使用了牛粪和通常的矿物肥料。通过分析堆肥和肥料,耕种的土壤和收获的物料,研究了有机肥料和矿物肥料的处理效果。还确定了谷物产量。有机肥改善了土壤的pH,CEC,有机质含量和NPK。发现土壤呼吸和氮矿化比纯矿物处理过的土壤要高。钾素吸收量得到改善,而谷物单产却没有受到影响。可以肯定的是,有机肥,特别是堆肥的使用,保持并增加了土壤肥力。该研究证明了在机车分析设施中使用该方法以跟踪整个回收过程的可行性(从废物到堆肥的生产)以及最终产品在野外的使用。
  • 【甲状腺细针细胞学检查并发喉返神经麻痹和不必要的根治性手术。】 复制标题 收藏 收藏
    DOI:10.1017/S0022215106002453 复制DOI
    作者列表:Hulin SJ,Harris KP
    BACKGROUND & AIMS: :Fine needle aspiration cytology (FNAC) is an important tool in the investigation of thyroid nodules and has few reported complications. We present the first report of recurrent laryngeal nerve palsy arising as a complication of thyroid nodule FNAC. This complication led to inaccurate diagnosis and unnecessarily radical surgery, with consequent increased morbidity.
    背景与目标: :细针穿刺细胞学检查(FNAC)是研究甲状腺结节的重要工具,很少有并发症报道。我们目前作为喉结节FNAC的并发症而出现的喉返神经麻痹的首次报道。这种并发症导致诊断不准确和不必要的根治性手术,从而增加发病率。
  • 【在正常和脱水大鼠中,μ阿片受体是否参与了内皮素-1从垂体的释放控制?】 复制标题 收藏 收藏
    DOI:10.1016/s0167-0115(97)02134-4 复制DOI
    作者列表:Płonowski A,Szymańska-Debińska T,Radzikowska M,Baranowska B,Woźniewicz B
    BACKGROUND & AIMS: UNLABELLED:The objective of the present study was to investigate whether the endogenous opioids are involved in the control of endothelin-1 release from the pituitary gland. To test this hypothesis we have measured the peripheral plasma concentration of ET-1 as well as the content of immunoreactive ET-1 (irET-1) in the pituitary in response to opioid receptors blockade in euhydrated and 24 h water-deprived Wistar-Kyoto rats. Placebo or naltrexone (50 micrograms/kg body wt.) were given i.v. in both groups. Trunk blood was collected to determine hematocrit, plasma sodium and ET-1 levels (RIA). Immunostaining of ET-1 in the whole pituitary glands was performed by colloidal gold labeling. The quantitative analysis of irET-1 was carried out under a light microscope using a computerized image analyzer (MultiScan). RESULTS:(1) Twenty-four-hour dehydration resulted in marked increase of peripheral concentration of ET-1. Naltrexone injection induced a significant elevation of ET-1 plasma concentration in both, dehydrated and control animals. (2) The content of irET-1 in anterior and intermediate lobes of the pituitary in dehydrated rats was markedly higher than in control group. (3) Naltrexone injection caused a rapid and significant reduction irET-1 within the anterior, intermediate and posterior lobes in dehydrated and control animals. CONCLUSIONS:(1) An elevation of irET-1 in the pituitary gland and peripheral circulation in dehydrated animals may play a role in maintaining of water-electrolyte balance. (2) The mu-opioid system appears to control the ET-1 release from the pituitary in normal and dehydrated animals.
    背景与目标: 未标记:本研究的目的是调查内源性阿片类药物是否参与垂体中内皮素-1的释放。为了检验这一假设,我们测量了在无水和缺水24小时的Wistar-Kyoto中阿片受体阻滞后垂体中ET-1的外周血浆浓度以及免疫反应性ET-1(irET-1)的含量大鼠。静脉注射安慰剂或纳曲酮(50微克/千克体重)。在两组中。收集躯干血液以确定血细胞比容,血浆钠和ET-1水平(RIA)。 ET-1在整个垂体中的免疫染色是通过胶体金标记进行的。使用计算机图像分析仪(MultiScan)在光学显微镜下对irET-1进行定量分析。
    结果:(1)脱水24小时导致ET-1的外周血浓度明显升高。纳曲酮注射液在脱水和对照动物中均引起ET-1血浆浓度的显着升高。 (2)脱水大鼠垂体前叶和中间叶中irET-1的含量明显高于对照组。 (3)纳曲酮注射液导致脱水和对照动物的前叶,中叶和后叶内的irET-1迅速大量降低。
    结论:(1)脱水动物垂体中irET-1的升高和外周循环可能在维持水电解质平衡中发挥了作用。 (2)在正常和脱水动物中,μ阿片样物质系统似乎可以控制ET-1从垂体的释放。
  • 【线粒体相关的己糖激酶在本氏烟草中对程序性细胞死亡的控制中发挥作用。】 复制标题 收藏 收藏
    DOI:10.1105/tpc.106.041509 复制DOI
    作者列表:Kim M,Lim JH,Ahn CS,Park K,Kim GT,Kim WT,Pai HS
    BACKGROUND & AIMS: :Recent findings suggest a pivotal role for mitochondria-associated hexokinase in the regulation of apoptosis in animal cells. In this study, virus-induced gene silencing (VIGS) of a hexokinase-encoding Hxk1 caused necrotic lesions on leaves, abnormal leaf morphology, and retarded plant growth in Nicotiana benthamiana. Hxk1 was associated with the mitochondria, and this association required the N-terminal membrane anchor. VIGS of Hxk1 reduced the cellular glucose-phosphorylating activity to approximately 31% of control levels without changing the fructose-phosphorylating activity and did not alter hexose phosphate content severely. The affected cells showed programmed cell death (PCD) morphological markers, including nuclear condensation and DNA fragmentation. Similar to animal cell apoptosis, cytochrome c was released into the cytosol and caspase-9- and caspase-3-like proteolytic activities were strongly induced. Furthermore, based on flow cytometry, Arabidopsis thaliana plants overexpressing Arabidopsis HXK1 and HXK2, both of which are predominantly associated with mitochondria, exhibited enhanced resistance to H(2)O(2)- and alpha-picolinic acid-induced PCD. Finally, the addition of recombinant Hxk1 to mitochondria-enriched fractions prevented H(2)O(2)/clotrimazole-induced cytochrome c release and loss of mitochondrial membrane potential. Together, these results show that hexokinase critically regulates the execution of PCD in plant cells, suggesting a link between glucose metabolism and apoptosis.
    背景与目标: :最近的发现表明线粒体相关的己糖激酶在调节动物细胞凋亡中起着关键作用。在这项研究中,编码己糖激酶的Hxk1的病毒诱导的基因沉默(VIGS)导致了本特烟草的叶片坏死性病变,异常的叶片形态并延缓了植物的生长。 Hxk1与线粒体相关联,这种关联需要N端膜锚。 Hxk1的VIGS可以将细胞的葡萄糖磷酸化活性降低至对照水平的约31%,而不会改变果糖磷酸化活性,并且不会严重改变磷酸己糖的含量。受影响的细胞显示出程序性细胞死亡(PCD)形态标志物,包括核浓缩和DNA片段化。与动物细胞凋亡相似,细胞色素c被释放到细胞质中,并强烈诱导了caspase-9-和caspase-3-like蛋白水解活性。此外,基于流式细胞仪,拟南芥植物过表达拟南芥HXK1和HXK2,这两个主要与线粒体相关联,表现出增强的抗H(2)O(2)-和α-吡啶甲酸诱导的PCD。最后,向线粒体富集的部分中添加重组Hxk1可以防止H(2)O(2)/克霉唑诱导的细胞色素c释放和线粒体膜电位的损失。总之,这些结果表明,己糖激酶严格调节植物细胞中PCD的执行,表明葡萄糖代谢与细胞凋亡之间存在联系。
  • 【血管紧张素转换酶抑制剂和主动脉破裂:基于人群的病例对照研究。】 复制标题 收藏 收藏
    DOI:10.1016/S0140-6736(06)69250-7 复制DOI
    作者列表:Hackam DG,Thiruchelvam D,Redelmeier DA
    BACKGROUND & AIMS: BACKGROUND:Angiotensin-converting enzyme (ACE) inhibitors prevent the expansion and rupture of aortic aneurysms in animals. We investigated the association between ACE inhibitors and rupture in patients with abdominal aortic aneurysms. METHODS:We did a population-based case-control study of linked administrative databases in Ontario, Canada. The sample included consecutive patients older than 65 (n=15,326) admitted to hospital with a primary diagnosis of ruptured or intact abdominal aortic aneurysm between April 1, 1992, and April 1, 2002. FINDINGS:Patients who received ACE inhibitors before admission were significantly less likely to present with ruptured aneurysm (odds ratio [OR] 0.82, 95% CI 0.74-0.90) than those who did not receive ACE inhibitors. Adjustment for demographic characteristics, risk factors for rupture, comorbidities, contraindications to ACE inhibitors, measures of health-care use, and aneurysm screening yielded similar results (0.83, 0.73-0.95). Consistent findings were noted in subgroups at high risk of rupture, including patients older than 75 years and those with a history of hypertension. Conversely, such protective associations were not observed for beta blockers (1.02, 0.89-1.17), calcium channel blockers (1.01, 0.89-1.14), alpha blockers (1.15, 0.86-1.54), angiotensin receptor blockers (1.24, 0.71-2.18), or thiazide diuretics (0.91, 0.78-1.07). INTERPRETATION:ACE inhibitors are associated with a reduced risk of ruptured abdominal aortic aneurysm, unlike other antihypertensive agents. Randomised trials of ACE inhibitors for prevention of aortic rupture might be warranted.
    背景与目标: 背景:血管紧张素转换酶(ACE)抑制剂可防止动物主动脉瘤的扩张和破裂。我们调查了腹主动脉瘤患者中ACE抑制剂与破裂之间的关系。
    方法:我们在加拿大安大略省的相关行政数据库中进行了基于人群的病例对照研究。该样本包括1992年4月1日至2002年4月1日之间入院的65岁以上的连续患者(n = 15,326),其主要诊断为腹主动脉瘤破裂或完整。
    结果:与未接受ACE抑制剂的患者相比,入院前接受ACE抑制剂的患者出现动脉瘤破裂的可能性显着降低(优势比[OR] 0.82,95%CI 0.74-0.90)。调整人口统计学特征,破裂危险因素,合并症,ACEI禁忌症,卫生保健措施和动脉瘤筛查得出相似的结果(0.83,0.73-0.95)。在高破裂风险的亚组(包括75岁以上和有高血压病史的患者)中发现了一致的发现。相反,对于β受体阻滞剂(1.02,0.89-1.17),钙通道阻滞剂(1.01,0.89-1.14),α受体阻滞剂(1.15,0.86-1.54),血管紧张素受体阻滞剂(1.24,0.71-2.18)未观察到这种保护性关联。 ,或噻嗪类利尿剂(0.91、0.78-1.07)。
    解释:与其他降压药不同,ACE抑制剂与降低腹主动脉瘤破裂的风险有关。 ACE抑制剂预防主动脉破裂的随机试验可能是必要的。
  • 【雌二醇调节反应的遗传控制的证据。对正常和病理性激素依赖性表型变异的影响。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Griffith JS,Jensen SM,Lunceford JK,Kahn MW,Zheng Y,Falase EA,Lyttle CR,Teuscher C
    BACKGROUND & AIMS: :The ovarian steroid hormone estrogen (E2) elicits a multiplicity of both systemic and uterotropic responses in vivo. For example, the administration of E2 to ovariectomized (Ovx) and sexually immature rodents leads to uterine-specific inflammatory infiltrates. In this study, we quantitated the number of eosinophils and BM8+, Ia+, and CD4+ cells in uteri obtained from adult Ovx control and E2-treated C57BL/6J, C3H/HeJ, and (C57BL/6J x C3H/HeJ) (B6C3) F1 hybrid mice. All three strains exhibited a significant increase in the number of uterine eosinophils and BM8+ macrophages after E2 treatment. However, C57BL/6J and B6C3 F1 hybrid mice responded with a greater number of infiltrating eosinophils and macrophages as compared with C3H/HeJ. A similar analysis of Ia+ and CD4+ cells showed that E2 treatment either down-regulates or does not affect the number of such cells in all three strains. Genome exclusion mapping using a (C57BL/6J x C3H/HeJ) x C3H/HeJ backcross population localized Est1, the major locus controlling the number of eosinophils infiltrating the uterus after E2 treatment, to chromosome 4. In addition, suggestive linkage to marker loci on chromosomes 10 and 16 was detected and evidence for locus interaction is presented. Our results conclusively demonstrate that E2-regulated/ dependent responses can be genetically controlled, indicating that the phenotypic variation observed in both the normal and pathological effects of E2 may, in part, be due to a genetic component.
    背景与目标: :卵巢类固醇激素雌激素(E2)在体内引起多种全身和子宫促反应。例如,将E2给予去卵巢(Ovx)和性不成熟的啮齿动物会导致子宫特异性炎症浸润。在这项研究中,我们量化了从成年Ovx对照和经E2处理的C57BL / 6J,C3H / HeJ和(C57BL / 6J x C3H / HeJ)(B6C3)获得的子宫中嗜酸性粒细胞和BM8,Ia和CD4细胞的数量F1杂种小鼠。在E2处理后,所有三个菌株均表现出子宫嗜酸性粒细胞和BM8巨噬细胞数量的显着增加。但是,与C3H / HeJ相比,C57BL / 6J和B6C3 F1杂种小鼠反应的浸润性嗜酸性粒细胞和巨噬细胞数量更多。对Ia和CD4细胞的类似分析显示,E2处理在所有三个菌株中均下调或不影响此类细胞的数量。使用(C57BL / 6J x C3H / HeJ)x C3H / HeJ回交群体定位的基因组排斥定位于Est1,Est1是控制E2处理后浸润子宫的嗜酸性粒细胞数量的主要基因座,并指向染色体4。检测到10号和16号染色体上的基因并提供了基因座相互作用的证据。我们的结果最终证明,E2调节/依赖性反应可以通过基因控制,这表明在E2的正常和病理效应中观察到的表型变异可能部分归因于遗传成分。
  • 【ColE1质粒复制的控制。 Rom蛋白与RNA I和RNA II形成的不稳定复合物的相互作用。】 复制标题 收藏 收藏
    DOI:10.1016/0022-2836(90)90231-a 复制DOI
    作者列表:Tomizawa J
    BACKGROUND & AIMS: :A transcript (RNA I) from ColE1 inhibits initiation of replication of the plasmid DNA by binding to the precursor of the primer RNA (RNA II). The ability of RNA I to inhibit replication is altered by the presence of a plasmid-specified small protein, Rom. In vitro, RNA I binds to RNA II to form a very unstable complex, C*. Binding of a single molecule of Rom converts C* to a more stable complex, Cm*. Each of these complexes, C* or Cm*, transforms to a more stable complex, C** or Cm**, respectively. While formation of complex C* or Cm* is inferred from the inhibition of binding caused by a second RNA I species, that of complex C** or Cm** is detected by alteration of RNase sensitivity. Complex C* converts to complex Cm* very rapidly upon addition of Rom to the medium and complex Cm* converts to complex C* very rapidly by removal of Rom from the medium. On the other hand, complexes C** and Cm** do not rapidly interconvert, but can eventually transform to the same stable final product. Thus, Rom affects binding of RNA I to RNA II through conversion of a very unstable early intermediate to a more stable complex, creating a second pathway for their stable binding.
    背景与目标: :来自ColE1的转录本(RNA I)通过与引物RNA(RNA II)的前体结合,抑制质粒DNA复制的开始。质粒指定的小蛋白质Rom的存在改变了RNA I抑制复制的能力。在体外,RNA I与RNA II结合形成非常不稳定的复合物C *。 Rom单个分子的结合将C *转化为更稳定的复合物Cm *。这些复合物C *或Cm *分别转换为更稳定的复合物C **或Cm **。虽然可以通过抑制第二种RNA I物种的结合来推断复合物C *或Cm *的形成,但可以通过改变RNA酶的敏感性来检测复合物C **或Cm **的形成。在向培养基中添加Rom时,复合物C *非常迅速地转化为复合物Cm *,并且通过从培养基中去除Rom,复合物Cm *非常迅速地转化为复合物C *。另一方面,复合物C **和Cm **不会快速相互转换,但最终可以转换为相同的稳定最终产物。因此,Rom通过将非常不稳定的早期中间体转化为更稳定的复合物,从而影响RNA I与RNA II的结合,从而为它们的稳定结合创造了第二条途径。
  • 【保护患者和环境-医院感染控制的新方面和新挑战。】 复制标题 收藏 收藏
    DOI:10.1016/s0195-6701(97)90086-4 复制DOI
    作者列表:Daschner FD,Dettenkofer M
    BACKGROUND & AIMS: Environmental pollution has become a major concern for the future of life on our planet; medical care, especially in hospitals, contributes significantly to this pollution. The increasing usage of highly-developed medical devices, drugs and disposable products are a drain on natural resources as well as financial ones. In this situation, it is a major task for hospital epidemiologists to maintain high standards of hygiene while reducing environmental pollution, reducing consumption of limited natural resources, and minimizing costs. The reduction of hospital waste, the control of polluting and toxic emissions, the avoidance of unnecessary disinfection procedures and disposables, the implementation of energy and water saving technologies are practicable measures in hospital ecology. To realize a sustainable development within hospitals, it is necessary that the need to maintain a balance between effective infection control and a good ecological environment is recognized and supported by health-care workers and the hospital management.

    背景与目标: 环境污染已经成为我们星球上未来生活的主要关注点;医疗服务,尤其是医院的医疗服务,是造成这种污染的重要原因。高度发达的医疗设备,药物和一次性产品的使用日益增加,这既浪费了自然资源,也浪费了金融资源。在这种情况下,医院流行病学家的主要任务是保持较高的卫生标准,同时减少环境污染,减少有限自然资源的消耗并最大程度地降低成本。减少医院浪费,控制污染和有毒物质排放,避免不必要的消毒程序和一次性用品,实施节能节水技术是医院生态学中的切实可行的措施。为了实现医院内部的可持续发展,必须在卫生保健工作者和医院管理人员的认识和支持下,在有效的感染控制和良好的生态环境之间保持平衡。

  • 【皮肤生物学中的神经肽控制机制:生理和临床意义。】 复制标题 收藏 收藏
    DOI:10.1038/sj.jid.5700429 复制DOI
    作者列表:Peters EM,Ericson ME,Hosoi J,Seiffert K,Hordinsky MK,Ansel JC,Paus R,Scholzen TE
    BACKGROUND & AIMS: :The skin as a barrier and immune organ is exposed to omnipresent environmental challenges such as irradiation or chemical and biologic hazards. Neuropeptides released from cutaneous nerves or skin and immune cells in response to noxious stimuli are mandatory for a fine-tuned regulation of cutaneous immune responses and tissue maintenance and repair. They initialize host immune responses, but are equally important for counter regulation of proinflammatory events. Interaction of the nervous and immune systems occurs both locally - at the level of neurogenic inflammation and immunocyte activation - and centrally - by controlling inflammatory pathways such as mononuclear activation or lymphocyte cytokine secretion. Consequently, a deregulated neurogenic immune control results in disease manifestation and frequently accompanies chronic development of cutaneous disorders. The current understanding, therapeutic options, and open questions of the role that neuropeptides such as substance P, calcitonin gene-related peptide, vasoactive intestinal peptide/pituitary adenylate cyclase-activating polypeptide, neuropeptide Y, or others play in these events are discussed. Progress in this field will likely result in novel therapies for the management of diseases characterized by deregulated inflammation, tissue remodeling, angiogenesis, and neoplasm.
    背景与目标: :作为屏障和免疫器官的皮肤暴露于无处不在的环境挑战中,例如辐射或化学和生物危害。皮肤神经或皮肤释放的神经肽以及对有害刺激作出反应的免疫细胞对于皮肤免疫反应以及组织维持和修复的微调调节是必不可少的。它们可以启动宿主的免疫反应,但对于调节促炎事件也同样重要。通过控制诸如单核激活或淋巴细胞细胞因子分泌之类的炎症途径,神经和免疫系统的相互作用既在局部发生(在神经源性炎症和免疫细胞激活的水平),也发生在中央。因此,神经源性免疫控制失调导致疾病表现,并经常伴随皮肤疾病的慢性发展。讨论了有关神经肽(例如P物质,降钙素基因相关肽,血管活性肠肽/垂体腺苷酸环化酶激活多肽,神经肽Y或其他物质)在这些事件中的作用的当前理解,治疗选择和开放性问题。该领域的进展可能会导致新的疗法来治疗以炎症失调,组织重塑,血管生成和肿瘤为特征的疾病。
  • 【I型糖尿病易感性候选基因的分析:2q31-35号染色体上基因的病例对照和家庭关联研究。】 复制标题 收藏 收藏
    DOI:10.2337/diab.46.6.1069 复制DOI
    作者列表:Owerbach D,Naya FJ,Tsai MJ,Allander SV,Powell DR,Gabbay KH
    BACKGROUND & AIMS: Recent genome searches suggest a putative linkage of many loci to susceptibility to type I diabetes. The chromosome 2q31-35 region is reported to be linked to susceptibility to type I diabetes and is thought to contain several diabetes susceptibility loci. These candidate genes include the HOXD gene cluster, BETA2, CTLA4, CD28, IGFBP2, and IGFBP5. Association studies in populations and families are required to confirm and/or identify the actual susceptibility loci. We hereby report several previously unknown DNA polymorphisms for HOXD8, BETA2, and IGFBP5, which we have used along with previously known polymorphisms of HOXD8 and CTLA4 to test whether these candidate loci are the susceptibility genes on chromosome 2q31-35. Using a case-control design with a subsequent family-association approach to confirm associations, we find no evidence that these candidate genes are associated with susceptibility to type I diabetes.

    背景与目标: 最近的基因组搜索表明,许多基因位点与I型糖尿病易感性的推测联系。据报道,染色体2q31-35与I型糖尿病易感性相关,并被认为含有几个糖尿病易感性基因座。这些候选基因包括HOXD基因簇,BETA2,CTLA4,CD28,IGFBP2和IGFBP5。需要在人群和家庭中进行协会研究,以确认和/或识别实际的易感基因座。我们在此报告了HOXD8,BETA2和IGFBP5的几种先前未知的DNA多态性,并将其与HOXD8和CTLA4的先前已知多态性一起用于测试这些候选基因座是否为2q31-35染色体上的易感性基因。使用病例对照设计和随后的家庭关联方法来确认关联,我们没有发现这些候选基因与I型糖尿病易感性相关的证据。

  • 【临床试验中缺少的数据:基于对照的均值插补和敏感性分析。】 复制标题 收藏 收藏
    DOI:10.1002/pst.1817 复制DOI
    作者列表:Mehrotra DV,Liu F,Permutt T
    BACKGROUND & AIMS: :In some randomized (drug versus placebo) clinical trials, the estimand of interest is the between-treatment difference in population means of a clinical endpoint that is free from the confounding effects of "rescue" medication (e.g., HbA1c change from baseline at 24 weeks that would be observed without rescue medication regardless of whether or when the assigned treatment was discontinued). In such settings, a missing data problem arises if some patients prematurely discontinue from the trial or initiate rescue medication while in the trial, the latter necessitating the discarding of post-rescue data. We caution that the commonly used mixed-effects model repeated measures analysis with the embedded missing at random assumption can deliver an exaggerated estimate of the aforementioned estimand of interest. This happens, in part, due to implicit imputation of an overly optimistic mean for "dropouts" (i.e., patients with missing endpoint data of interest) in the drug arm. We propose an alternative approach in which the missing mean for the drug arm dropouts is explicitly replaced with either the estimated mean of the entire endpoint distribution under placebo (primary analysis) or a sequence of increasingly more conservative means within a tipping point framework (sensitivity analysis); patient-level imputation is not required. A supplemental "dropout = failure" analysis is considered in which a common poor outcome is imputed for all dropouts followed by a between-treatment comparison using quantile regression. All analyses address the same estimand and can adjust for baseline covariates. Three examples and simulation results are used to support our recommendations.
    背景与目标: :在一些随机(药物与安慰剂)临床试验中,关注的估计是临床终点的人群平均治疗间差异,其不受“挽救”药物的混杂影响(例如,HbA1c在24岁时偏离基线)不论是否或何时终止指定的治疗,都无需救援药物即可观察到的数周时间)。在这种情况下,如果某些患者在试验期间过早中断试验或开始抢救药物,则会出现数据丢失的问题,后者需要丢弃救援后的数据。我们提醒您,通常使用的混合效应模型重复测量分析会在随机假设的情况下出现嵌入缺失,从而可能对上述感兴趣的估计值进行夸大的估计。之所以会发生这种情况,部分原因是由于对药物部门中的“辍学”(即缺少目标终点数据缺失的患者)过于乐观的平均值的隐式估算。我们提出了另一种方法,即用安慰剂(主要分析)下整个终点分布的估计均值(主要分析)或临界点框架内一系列越来越保守的均值(敏感性分析)明确替换掉药物臂退出的均值);不需要患者级别的估算。考虑进行补充的“辍学=失败”分析,在该分析中,对所有辍学的普遍不良结果进行了归因,然后使用分位数回归进行了治疗之间的比较。所有分析都针对相同的估计值,并且可以针对基线协变量进行调整。三个示例和仿真结果用于支持我们的建议。
  • 【严峻环境中的破坏控制手术研究组(DCSAERG):一个动态程序,可帮助进行实时远程指导/远程诊断,以解决极端严酷环境中的失血问题。】 复制标题 收藏 收藏
    DOI:10.1097/TA.0000000000001483 复制DOI
    作者列表:Kirkpatrick AW,McKee JL,McBeth PB,Ball CG,LaPorta A,Broderick T,Leslie T,King D,Wright Beatty HE,Keillor J,Tien H
    BACKGROUND & AIMS: :Hemorrhage is the most preventable cause of posttraumatic death. Many cases are potentially anatomically salvageable, yet remain lethal without logistics or trained personnel to deliver diagnosis or resuscitative surgery in austere environments. Revolutions in technology for remote mentoring of ultrasound and surgery may enhance capabilities to utilize the skill sets of non-physicians. Thus, our research collaborative explored remote mentoring to empower non-physicians to address junctional and torso hemorrhage control in austere environments. Major studies involved using remote-telementored ultrasound (RTMUS) to identify torso and junctional exsanguination, remotely mentoring resuscitative surgery for torso hemorrhage control, understanding and mitigating physiological stress during such tasks, and the technical practicalities of conducting damage control surgery (DCS) in austere environments. Iterative projects involved randomized guiding of firefighters to identify torso (RCT) and junctional (pilot) hemorrhage using RTMUS, randomized remote mentoring of MedTechs conducting resuscitative surgery for torso exsanguination in an anatomically realistic surgical trainer ("Cut Suit") including physiological monitoring, and trained surgeons conducting a comparative randomized study for torso hemorrhage control in normal (1g) versus weightlessness (0g). This work demonstrated that firefighters could be remotely mentored to perform just-in-time torso RTMUS on a simulator. Both firefighters and mentors were confident in their abilities, the ultrasounds being 97% accurate. An ultrasound-naive firefighter in Memphis could also be remotely mentored from Hawaii to identify and subsequently tamponade an arterial junctional hemorrhage using RTMUS in a live tissue model. Thereafter, both mentored and unmentored MedTechs and trained surgeons completed resuscitative surgery for hemorrhage control on the Cut-Suit, demonstrating practicality for all involved. While remote mentoring did not decrease blood loss among MedTechs, it increased procedural confidence and decreased physiologic stress. Therefore, remote mentoring may increase the feasibility of non-physicians conducting a psychologically daunting task. Finally, DCS in weightlessness was feasible without fundamental differences from 1g. Overall, the collective evidence suggests that remote mentoring supports diagnosis, noninvasive therapy, and ultimately resuscitative surgery to potentially rescue those exsanguinating in austere environments and should be more rigorously studied.
    背景与目标: :出血是创伤后死亡的最可预防原因。许多病例在解剖学上可能是可挽救的,但如果没有后勤人员或训练有素的人员在严酷的环境中进行诊断或复苏手术,则可能致死。超声和手术的远程指导技术的革命可能会增强利用非医师技能的能力。因此,我们的研究合作探索了远程指导,以使非医师能够在严峻的环境中解决交界处和躯干出血的控制问题。重大研究涉及使用远程元素超声(RTMUS)识别躯干和关节血流失血,远程指导复苏手术以控制躯干出血,了解和缓解此类任务期间的生理压力以及在严格的条件下进行损伤控制手术(DCS)的技术实用性环境。迭代项目涉及使用RTMUS随机指导消防员以识别躯干(RCT)和交界处(飞行员)出血,在解剖学上现实的外科培训师(Cut Suit)中进行进行复苏性躯干放血手术的MedTechs的随机远程指导,包括生理监测,以及训练有素的外科医生,对正常(1g)和失重(0g)的躯体出血控制进行比较随机研究。这项工作表明,可以远程指导消防员在模拟器上执行即时躯干RTMUS。消防员和指导者都对自己的能力充满信心,超声波准确率达97%。孟菲斯市的一名初次使用超声的消防员也可以从夏威夷进行远程指导,以在活组织模型中使用RTMUS识别并随后压塞动脉结膜出血。此后,受指导和未受指导的MedTechs以及受过训练的外科医生都完成了复苏手术,以控制Cut-Suit上的出血,证明了所有参与者的实用性。尽管远程指导并没有减少MedTechs的失血量,但它增加了程序的置信度并降低了生理压力。因此,远程指导可能会增加非医师执行心理艰巨任务的可行性。最终,失重的DCS是可行的,与1g的差异不大。总体而言,集体证据表明,远程指导支持诊断,无创治疗以及最终的复苏手术,以挽救那些在严酷环境中放血的人,因此应进行更严格的研究。

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