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Relationship of physical fitness vs body mass index with coronary artery disease and cardiovascular events in women 总被引:7,自引:0,他引:7
Wessel TR Arant CB Olson MB Johnson BD Reis SE Sharaf BL Shaw LJ Handberg E Sopko G Kelsey SF Pepine CJ Merz NB 《JAMA》2004,292(10):1179-1187
Context Individual contributions of obesity and physical fitness (physical activity and functional capacity) to risk of coronary heart disease in women remain unclear. Objective To investigate the relationships of measures of obesity (body mass index [BMI], waist circumference, waist-hip ratio, and waist-height ratio) and physical fitness (self-reported Duke Activity Status Index [DASI] and Postmenopausal Estrogen-Progestin Intervention questionnaire [PEPI-Q] scores) with coronary artery disease (CAD) risk factors, angiographic CAD, and adverse cardiovascular (CV) events in women evaluated for suspected myocardial ischemia. Design, Setting, and Participants The National Heart, Lung, and Blood Institutesponsored Women's Ischemia Syndrome Evaluation (WISE) is a multicenter prospective cohort study. From 1996-2000, 936 women were enrolled at 4 US academic medical centers at the time of clinically indicated coronary angiography and then assessed (mean follow-up, 3.9 [SD, 1.8] years) for adverse outcomes. Main Outcome Measures Prevalence of obstructive CAD (any angiographic stenosis 50%) and incidence of adverse CV events (all-cause death or hospitalization for nonfatal myocardial infarction, stroke, congestive heart failure, unstable angina, or other vascular events) during follow-up. Results Of 906 women (mean age, 58 [SD, 12] years) with complete data, 19% were of nonwhite race, 76% were overweight (BMI 25), 70% had low functional capacity (DASI scores <25, equivalent to 7 metabolic equivalents [METs]), and 39% had obstructive CAD. During follow-up, 337 (38%) women had a first adverse event, 118 (13%) had a major adverse event, and 68 (8%) died. Overweight women were more likely than normal weight women to have CAD risk factors, but neither BMI nor abdominal obesity measures were significantly associated with obstructive CAD or adverse CV events after adjusting for other risk factors (P = .05 to .88). Conversely, women with lower DASI scores were significantly more likely to have CAD risk factors and obstructive CAD (44% vs 26%, P<.001) at baseline, and each 1-MET increase in DASI score was independently associated with an 8% (hazard ratio, 0.92; 95% confidence interval, 0.85-0.99; P = .02) decrease in risk of major adverse CV events during follow-up. Conclusions Among women undergoing coronary angiography for suspected ischemia, higher self-reported physical fitness scores were independently associated with fewer CAD risk factors, less angiographic CAD, and lower risk for adverse CV events. Measures of obesity were not independently associated with these outcomes. 相似文献
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跟骨定量超声骨质测量参数与骨密度及骨组织形态计量学指标的关系 总被引:1,自引:0,他引:1
目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。 相似文献
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Sequence Analysis of the RNA Polymerase Gene of Foot-and-Mouth Disease Virus Serotype Asia1 总被引:1,自引:0,他引:1
George M Venkataramanan R Pattnaik B Sanyal A Gurumurthy CB Hemadri D Tosh C 《Virus genes》2001,22(1):21-26
The complete nucleotide (nt.) sequence of the RNA polymerase (3D) gene and 81 nt. in the 3-untranslated region of foot-and-mouth disease virus (FMDV) serotype Asia1 (IND63/72) was determined and compared with the sequence of other FMDV serotypes. The 3D genomic region was 1410 nt. long encoding 470 amino acids with an inframe stop codon (TAA) at nt. position 1411–1413. The deduced amino acid sequence of the protein showed 8 conserved motifs as reported in other picornaviruses, 2 of which are 100% identical across the serotypes. Antigenic regions in the polymerase protein were predicted and found to be located at the N-terminus of the protein. The phylogenetic analysis showed that the FMD viruses were segregated into different clusters based on geographical origin; the Asia1 virus did not cluster tightly with any of the geographical groups. 相似文献
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H-2-restricted cytotoxic effectors generated in vitro by the addition of trinitrophenyl-conjugated soluble proteins 总被引:3,自引:3,他引:3 下载免费PDF全文
A Schmitt-Verhulst CB Pettinelli PA Henkart JK Lunney GM Shearer 《The Journal of experimental medicine》1978,147(2):352-368
Murine spleen cells from normal donors were cultured in vitro with trinitrobenzene sulfonate (TNBS)-conjugated soluble proteins, i.e., bovine gamma globulin (TNP-BGG) or bovine serum albumin (TNP-BSA). Addition of 100 μg of any of these TNP-proteins to the spleen cell cultures led to the generation of cytotoxic T-cell effectors which were H-2-restricted and TNP- specific. The lytic potential of such effectors was comparable to that generated by sensitization with TNBS-modified syngeneic cells, and was restricted to haplotypes shared at the K or K plus I-A, or the D regions of the H-2 complex. Greater effecter cell activity was generated by addition of TNP-BGG against TNBS-modified targets which shared K plus I-A than against modified targets which shared the D region with the responding cells, which suggests that the same immune response genes are involved when the response is generated by the addition of TNP-conjugated soluble proteins or of TNBS- modified cells. H-2-restricted, TNP-specific effecter cells were generated by culturing mouse spleen cells with syngeneic cells which had been preincubated with TNP- BGG or TNP-BSA for 1.5 h. The addition of unconjugated soluble proteins to the cultures did not result in cytotoxic effectors detectable on H-2-matched targets, whether the targets were prepared by modification with TNBS, or by incubation with either the unconjugated or TNP-conjugated proteins. Depletion of phagocytic cells in the tumor preparation by Sephadex G-10 column fractionation before incubation with TNP-BSA had no effect on their lysis by the relevant effector cells. Immunofluorescent staining of tumor target cells with anti-TNP antibodies indicated that TNP could be detected on the tumor cells within 10 rain of incubation with TNP-BSA. The cytotoxic response generated by addition of the TNP-proteins to spleen cell cultures was found to be T-cell dependent at the effector phase, as shown by the sensitivity of the lytic phase to absorbed RAMB and complement. Furthermore, the response did not appear to be attributable to antibody-dependent cellular cytotoxicity. Three mechanisms were considered which could account for the generation of H-2-restricted, TNP-specific, cytotoxic T-cell effectors by the addition of soluble TNP-proteins. These include covalent linkage of activated TNP groups from the soluble proteins to cell surface components, macrophage processing of the soluble conjugates and presentation to the responding lymphocytes in association with H-2-coded self structures, or hydrophobic interaction of the TNP-proteins to cell surfaces. Results obtained from sodium dodecyl sulfate gel patterns indicating that cell-bound TNP was still linked to BSA, and the observation that phagocytic-depleted cells could interact with the soluble TNP-proteins and function as H-2-restricted targets, appear not to favor the first two proposed mechanisms. 相似文献
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VH gene expression is restricted in anti-IgG antibodies from MRL autoimmune mice 总被引:2,自引:1,他引:2 下载免费PDF全文
Antibodies directed against IgG and DNA are found in the sera of autoimmune MRL/Mp lpr/lpr mice. Little is known of the molecular mechanisms underlying expression of such autoantibodies. We have investigated the binding diversity and pattern of VH gene expression in a panel of murine anti-IgG antibodies. We constructed eight hybridoma clones secreting IgM antibodies that bound to mouse IgG by using spleen cells from MRL/Mp lpr/lpr mice varying in age from 4 to 15 wk; one clone was derived from a 32-wk-old MRL +/+ mouse. The monoclonal IgM products exhibited varying binding specificities for intact mouse IgG, fragments of mouse IgG [Fc, Fab, (Fab')2], and heterologous IgG. Two of these antibodies crossreacted with B and/or Z DNA. Probes from seven of eight identified mouse VH gene families (7183, S107, Q52, J558, J606, 36-60, and 3609) were hybridized under high-stringency conditions with cytoplasmic RNA blots from each clone. Six clones hybridized only with the probe from the five-member 36-60 family. The remaining three clones crosshybridized with the 36-60 probe and the probe from the 60 member J558 family, perhaps reflecting somatic mutation from the original germline VH gene resulting in recognition by a probe from another family, in addition to the probe from the original germline family. Our results indicate that spontaneous MRL lpr/lpr anti-IgG antibodies are encoded predominantly by the 36-60 VH gene family and imply a nonrandom selection of this VH gene family in the production of these antibodies. 相似文献