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排序方式: 共有525条查询结果,搜索用时 46 毫秒
51.
Vijaya Karoor Derek Strassheim Timothy Sullivan Alexander Verin Nagavedi S. Umapathy Edward C. Dempsey Daniel N. Frank Kurt R. Stenmark Evgenia Gerasimovskaya 《International journal of molecular sciences》2021,22(18)
Pulmonary hypertension (PH) is a progressive cardiovascular disorder in which local vascular inflammation leads to increased pulmonary vascular remodeling and ultimately to right heart failure. The HDAC inhibitor butyrate, a product of microbial fermentation, is protective in inflammatory intestinal diseases, but little is known regarding its effect on extraintestinal diseases, such as PH. In this study, we tested the hypothesis that butyrate is protective in a Sprague–Dawley (SD) rat model of hypoxic PH. Treatment with butyrate (220 mg/kg intake) prevented hypoxia-induced right ventricular hypertrophy (RVH), hypoxia-induced increases in right ventricular systolic pressure (RVSP), pulmonary vascular remodeling, and permeability. A reversal effect of butyrate (2200 mg/kg intake) was observed on elevated RVH. Butyrate treatment also increased the acetylation of histone H3, 25–34 kDa, and 34–50 kDa proteins in the total lung lysates of butyrate-treated animals. In addition, butyrate decreased hypoxia-induced accumulation of alveolar (mostly CD68+) and interstitial (CD68+ and CD163+) lung macrophages. Analysis of cytokine profiles in lung tissue lysates showed a hypoxia-induced upregulation of TIMP-1, CINC-1, and Fractalkine and downregulation of soluble ICAM (sICAM). The expression of Fractalkine and VEGFα, but not CINC-1, TIMP-1, and sICAM was downregulated by butyrate. In rat microvascular endothelial cells (RMVEC), butyrate (1 mM, 2 and 24 h) exhibited a protective effect against TNFα- and LPS-induced barrier disruption. Butyrate (1 mM, 24 h) also upregulated tight junctional proteins (occludin, cingulin, claudin-1) and increased the acetylation of histone H3 but not α-tubulin. These findings provide evidence of the protective effect of butyrate on hypoxic PH and suggest its potential use as a complementary treatment for PH and other cardiovascular diseases. 相似文献
52.
Stephanie Simoncini Hanna Coppola Angela Rocca Isaline Bachmann Estelle Guillot Leila Zippo Franoise Dignat-George Florence Sabatier Romain Bedel Anne Wilson Nathalie Rosenblatt-Velin Jean-Baptiste Armengaud Steeve Mentrey Anne-Christine Peyter Umberto Simeoni Catherine Yzydorczyk 《International journal of molecular sciences》2021,22(18)
Infants born after intrauterine growth restriction (IUGR) are at risk of developing arterial hypertension at adulthood. The endothelium plays a major role in the pathogenesis of hypertension. Endothelial colony-forming cells (ECFCs), critical circulating components of the endothelium, are involved in vasculo-and angiogenesis and in endothelium repair. We previously described impaired functionality of ECFCs in cord blood of low-birth-weight newborns. However, whether early ECFC alterations persist thereafter and could be associated with hypertension in individuals born after IUGR remains unknown. A rat model of IUGR was induced by a maternal low-protein diet during gestation versus a control (CTRL) diet. In six-month-old offspring, only IUGR males have increased systolic blood pressure (tail-cuff plethysmography) and microvascular rarefaction (immunofluorescence). ECFCs isolated from bone marrow of IUGR versus CTRL males displayed a decreased proportion of CD31+ versus CD146+ staining on CD45− cells, CD34 expression (flow cytometry, immunofluorescence), reduced proliferation (BrdU incorporation), and an impaired capacity to form capillary-like structures (Matrigel test), associated with an impaired angiogenic profile (immunofluorescence). These dysfunctions were associated with oxidative stress (increased superoxide anion levels (fluorescent dye), decreased superoxide dismutase protein expression, increased DNA damage (immunofluorescence), and stress-induced premature senescence (SIPS; increased beta-galactosidase activity, increased p16INK4a, and decreased sirtuin-1 protein expression). This study demonstrated an impaired functionality of ECFCs at adulthood associated with arterial hypertension in individuals born after IUGR. 相似文献
53.
Blumenthal James A.; Sherwood Andrew; Gullette Elizabeth C. D.; Georgiades Anastasia; Tweedy Damon 《Canadian Metallurgical Quarterly》2002,70(3):569
Despite recent advances in the medical management of hypertension, chronically elevated blood pressure remains a major health problem in the United States, affecting almost 50 million Americans. It is widely recognized that lifestyle factors contribute to the development and maintenance of elevated blood pressure. This article critically reviews current approaches to the nonpharmacological treatment of high blood pressure and highlights outcome studies of exercise, weight loss and dietary modification, and stress management and relaxation therapies. Methodological issues in the assessment and treatment of hypertension are discussed, along with possible mechanisms by which lifestyle modification may reduce elevated blood pressure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
高血压病是一种危害人类健康的严重疾病,尽管高血压的临床治疗已经取得较好疗效,但仍存在不少药物耐受性等不同类型的顽固性高血压,而且高血压的并发症如心力衰竭、脑卒中等发病率仍居高不下,因此,非药物治疗策略的深入研发与应用已成为高血压治疗的一个重要方面。交感神经系统在高血压发生发展中起着关键性作用,目前大多数高血压防治的非药物治疗技术主要通过靶向调节机体交感神经功能来实现,这些技术主要包括深部脑刺激、肾动脉神经射频消融术、中央髂动静脉吻合术、压力反射激活疗法、血管内压力反射放大疗法、颈动脉体切除术等。本综述重点对上述基于交感神经系统的非药物治疗方法的应用现状和相关优缺点进行回顾总结,为高血压的有效治疗提供新思路和多重选择。 相似文献
55.
针对国内某特钢厂新上的四流H型双通道感应加热中间包,为改善中间包内流体流动状态,设计了倒八字型与V型两种控流装置。应用数值模拟的方法对两种不同控流装置下的中间包流场、RTD曲线、温度场进行了模拟。结果表明,倒八字型控流装置平均停留时间1 469.6 s,死区体积比5.83%,边部水口与中间水口的最大温差3 K;与V型控流装置相比,平均停留时间延长了41.9 s,死区体积相应降低了4.09%,边部水口与中间水口的最大温差减少了2 ℃。湍流抑制器+倒八字型控流装置设计能更好改善四流大方坯H型双通道感应加热中间包流体流动性。 相似文献
56.
The effect of substituting Morton Lite Salt or Mineral Salt for sodium chloride in neutral emulsion and in mayonnaise was evaluated by using 1.00% sodium chloride, 1.25% Morton Lite Salt and 1.40% Mineral Salt of the emulsion weight. None, 1.00%, 2.00% and 3.00% of lactose were used to mask the bitter taste associated with potassium chloride. A triangle test using twelve to fifteen panelists was used. Results indicated that both Morton Lite Salt and Mineral Salt had a significant different taste (P ≤ 0.01) as compared with sodium chloride when they were used with none and 1.00% of lactose. Samples which had 2.00% or 3.00% lactose showed no significant taste difference between Morton Lite Salt or Mineral Salt and sodium chloride. It was concluded that a bitter masking agent such as lactose is needed when Morton Lite Salt or Mineral Salt is used to substitute sodium chloride in mayonnaise. 相似文献
57.
Tuomisto Martti T.; Majahalme Silja; K?h?nen Mika; Fredrikson Mats; Turjanmaa V?in? 《Canadian Metallurgical Quarterly》2005,24(1):77
Increased blood pressure (BP) reactivity to subtypes of psychological stimuli may differentially predict the development of future BP elevation or hypertension. The authors present the 9-12-year follow-up results of 82 (86%) of 95 male participants with different BP levels. They were healthy, untreated, and age-matched volunteers from a routine health checkup carried out on all 35-, 40-, and 45-year-olds from a medium-sized city. Intra-arterial systolic blood pressure (SBP) during the psychological tasks improved the prediction of future casual SBP and noninvasive 24-hr ambulatory SBP compared with predictions from casual diagnostic measurements. Diastolic blood pressure (DBP) was very useful when added to casual DBP in predicting the need for antihypertensive medication. Reactivity to active tasks especially predicts the need for antihypertensive medication. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
本文介绍了包钢薄板坯连铸主厂房钢结构的设计及特点。该厂房为单层重型工业厂房,下柱为组合式H型钢双肢柱,屋面大梁为焊接工字钢梁,基本柱距为12m,车间设置295t/67t/22t吊车,屋面和墙面采用彩色压型钢板。同时,在结构选型和构造方面有新的改进和发展。 相似文献
59.
60.
吕敏 《南京工业职业技术学院学报》2010,10(3):96-97
针对高职院校教职工中高血压病患者显著增多的趋势,探讨了高职院校教职工患高血压病的原因,对高职院校卫生医疗保健机构如何做好高血压病的防治与管理工作提出了建议。 相似文献