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51.
Pleiotropic effects of statins: do they matter? 总被引:7,自引:0,他引:7
Treatment with the 3-hydroxy-3-methylglutaryl coenyzme A reductase inhibitors (or statins) reduces the risk for cardiovascular events across a broad spectrum of patient profiles, as evidenced by both primary prevention and secondary prevention trials. Improved survival by way of reduced deaths from coronary heart disease was also reported with these agents, which are primarily indicated for substantial reduction in LDL-cholesterol levels. However, the statins are extremely complex drugs and exhibit a wide variety of vascular effects that may or may not be dependent on their lipid-modifying properties. These so-called pleiotropic effects include alterations of endothelial function, inflammation, coagulation, and plaque stability. The relative contribution of the nonlipid effects of statin therapy to the well-documented clinical benefits is currently under intense investigation. 相似文献
52.
Borchers MT Crosby J Farmer S Sypek J Ansay T Lee NA Lee JJ 《American journal of physiology. Lung cellular and molecular physiology》2001,280(4):L813-L821
Lymphocyte and/or eosinophil recruitment is dependent on the sequential interactions between adhesion molecules expressed on activated endothelial cells and both leukocyte subtypes. Endothelial P- and E-selectins mediate tethering and rolling of leukocytes through interactions with P-selectin glycoprotein ligand-1 (PSGL-1), and diapedesis subsequently occurs by engagement of endothelial vascular cell adhesion molecule-1 and CD49d (alpha(4)-integrins). The anti-inflammatory potential of interfering with these adhesive interactions was assessed with an ovalbumin challenge mouse model of asthma. Administration of a soluble form of PSGL-1 reduced eosinophils (80%) and lymphocytes (50%) in bronchoalveolar lavage fluid without affecting epithelial changes or airway hyperreactivity (AHR). In contrast, although administration of anti-CD49d monoclonal antibodies (PS/2) resulted in similar reductions in eosinophils (75%) and lymphocytes (50%), PS/2 reduced and abolished mucous cell metaplasia and AHR, respectively. Administration of both PSGL-1 and PS/2 had the additive effect of eliminating eosinophils from the airways (96% decrease), with few or no additional reductions (relative to PS/2 administration alone) in lymphocyte recruitment, mucous cell metaplasia, or AHR. These data show that eosinophils and lymphocytes differentially utilize adhesive interactions during recruitment and that the inhibition of AHR is independent of this recruitment. 相似文献
53.
Farmer KH 《American journal of primatology》2002,58(3):117-132
While wild populations continue to decrease, the number of orphaned primates, sanctuaries, and attempts to reintroduce primates back to the natural environment are increasing. An umbrella organization called the Pan-African Sanctuary Alliance (PASA) was formed in 2000 and recently the IUCN Reintroduction Specialist Group developed a set of specific policy guidelines for primates (2002). Data presented in this report are based upon questionnaire responses by managers from 17 African facilities that have become members of PASA (membership in PASA is defined by attendance at an annual PASA workshop). These PASA facilities house over 500 great apes. (There may be other facilities not represented here simply because their managers did not attend a PASA workshop.) The majority of the apes arrived at the sanctuaries when they were less than 4 years old and half were confiscated. Over 40% were found awaiting sale, and 30% had been previously kept as pets. Common ailments upon arrival included internal parasites, behavioral abnormalities, and malnutrition; 20% of the total sanctuary population died prematurely. Most sanctuaries use a combination of enclosures surrounded by electric fencing and cages to accommodate the apes. Sanctuaries actively participate in conservation education, habitat protection, tourism, scientific data collection, local development, and reintroduction. The median total facility operating cost was 65,000 US dollars per annum. The median facility cost per ape was 2,222 US dollars per annum. Most funding comes from overseas nongovernmental agencies. Discussion focuses on evaluating the present status of sanctuaries, the problems facing them, and their potential role in African conservation issues. 相似文献
54.
Targeted disruption of the murine Bin1/Amphiphysin II gene does not disable endocytosis but results in embryonic cardiomyopathy with aberrant myofibril formation 下载免费PDF全文
55.
Perni RB Britt SD Court JC Courtney LF Deininger DD Farmer LJ Gates CA Harbeson SL Kim JL Landro JA Levin RB Luong YP O'Malley ET Pitlik J Rao BG Schairer WC Thomson JA Tung RD Van Drie JH Wei Y 《Bioorganic & medicinal chemistry letters》2003,13(22):4059-4063
Tetrapeptide-based peptidomimetic compounds have been shown to effectively inhibit the hepatitis C virus NS3.4A protease without the need of a charged functionality. An aldehyde is used as a prototype reversible electrophilic warhead. The SAR of the P1 and P2 inhibitor positions is discussed. 相似文献
56.
57.
Eosinophil major basic protein-1 does not contribute to allergen-induced airway pathologies in mouse models of asthma 总被引:4,自引:0,他引:4
Denzler KL Farmer SC Crosby JR Borchers M Cieslewicz G Larson KA Cormier-Regard S Lee NA Lee JJ 《Journal of immunology (Baltimore, Md. : 1950)》2000,165(10):5509-5517
The relationship between eosinophils and the development of Ag-induced pulmonary pathologies, including airway hyper-responsiveness, was investigated using mice deficient for the secondary granule component, major basic protein-1 (mMBP-1). The loss of mMBP-1 had no effect on OVA-induced airway histopathologies or inflammatory cell recruitment. Lung function measurements of knockout mice demonstrated a generalized hyporeactivity to methacholine-induced airflow changes (relative to wild type); however, this baseline phenotype was observable only with methacholine; no relative airflow changes were observed in response to another nonspecific stimulus (serotonin). Moreover, OVA sensitization/aerosol challenge of wild-type and mMBP-1(-/-) mice resulted in identical dose-response changes to either methacholine or serotonin. Thus, the airway hyper-responsiveness in murine models of asthma occurs in the absence of mMBP-1. 相似文献
58.
In October 1995 the UK Committee on Safety of Medicines advised that combined oral contraceptives (OCs) containing either gestodene or desogestrel were associated with twice the risk of venous thromboembolism compared with older products. This study was conducted to compare the incidence of venous thromboembolism among women taking combined OCs before and after the October 1995 pill scare. Using data from the General Practice Research Database, a total of 304 practices were analyzed. Overall, results show that use of third-generation combined OCs fell from 53% during the period of January 1993 to October 1995 to 14% during the period of November 1995 to December 1998. No significant change was noted in the incidence of venous thromboembolism between the two periods after age was adjusted for (incidence ratio, 1.04; 95% confidence interval, 0.78-1.39). Based on these findings, it is concluded that third-generation OCs are not associated with a twofold increase in risk of venous thromboembolism compared with older progestogens. 相似文献
59.
60.
Fatty acid ketodienes and fatty acid ketotrienes: Michael addition acceptors that accumulate in wounded and diseased Arabidopsis leaves 总被引:1,自引:0,他引:1
Vollenweider S Weber H Stolz S Chételat A Farmer EE 《The Plant journal : for cell and molecular biology》2000,24(4):467-476
Physical damage and disease are known to lead to changes in the oxylipin signature of plants. We searched for oxylipins produced in response to both wounding and pathogenesis in Arabidopsis leaves. Linoleic acid 9- and 13-ketodienes (KODEs) were found to accumulate in wounded leaves as well as in leaves infected with the pathogen Pseudomonas syringae pv. tomato (Pst). Quantification of the compounds showed that they accumulated to higher levels during the hypersensitive response to Pst avrRpm1 than during infection with a Pst strain lacking an avirulence gene. KODEs are Michael addition acceptors, containing a chemically reactive alpha,beta-unsaturated carbonyl group. When infiltrated into leaves, KODEs were found to induce expression of the GST1 gene, but vital staining indicated that these compounds also damaged plant cells. Several molecules typical of lipid oxidation, including malonaldehyde, also contain the alpha,beta-unsaturated carbonyl reactivity feature, and, when delivered in a volatile form, powerfully induced the expression of GST1. The results draw attention to the potential physiological importance of naturally occurring Michael addition acceptors in plants. In particular, these compounds could act directly, or indirectly via cell damage, as powerful gene activators and might also contribute to host cell death. 相似文献