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1.

Objectives

We examined the association between three inflammatory markers (Interleukin (IL)-6, C-reactive protein (CRP), tumor necrosis factor (TNF)-α) and incident lung cancer using baseline, updated, and averaged inflammatory measures in older adults.

Methods

We fitted multivariable Cox models to assess whether circulating levels of inflammation markers were associated with incident lung cancers in the Health Aging, Body and Composition (HealthABC) prospective cohort of 3075 older adults aged 70–79?years at baseline. IL-6 and CRP were measured biennially, whereas TNF-α was measured at baseline.

Results

Baseline levels of IL-6 were significantly associated with incident lung cancer risk in a model that adjusted for age, gender, race, and site (Model 1) (Hazard RatioT3 vs. T1: 3.34, 95% Confidence Interval: 1.91, 5.85) and in a model adjusted for health factors linked to chronic inflammation (Model 2) (HR T3 vs. T1: 2.57, 95% CI: 1.41, 4.65). The associations observed in time-updated IL-6 (HR T3 vs. T1: 2.47, 95% CI: 1.43, 4.28), cumulatively averaged IL-6 (HR T3 vs. T1: 2.47, 95% CI: 1.43, 4.35), and baseline CRP levels (HR T3 vs. T1: 1.85, 95% CI: 1.11, 3.08) with incident lung cancer in Model 1 were not statistically significant in Model 2.

Conclusions

Baseline CRP and IL-6 levels were associated with increased risk of lung cancer in Model 1 and both models, respectively. Chronic IL-6 inflammation, as quantified by repeated measures was associated with incident lung cancer in Model 1, but not Model 2. Further research is needed to understand the role of CRP and IL-6 in lung carcinogenesis.  相似文献   
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The aim of the present study was to evaluate pregnancy-related changes in autonomic regulatory functions in healthy subjects. We studied cardiovascular autonomic responses to head-up tilt (HUT) in 28 pregnant women during the third trimester of pregnancy and 3 months after parturition. The maternal ECG and non-invasive beat-to-beat blood pressure were recorded in the horizontal position (left-lateral position) and during HUT in the upright position. Stroke volume was assessed from blood pressure signal by using the arterial pulse contour method. Heart rate variability (HRV) was analysed in frequency domain, and baroreflex sensitivity by the cross-spectral and the sequence methods. In the horizontal position, all frequency components of HRV were lower during pregnancy than 3 months after parturition (P < 0.01 to <0.001), while pregnancy had no influence on normalized low frequency and high frequency powers. During pregnancy haemodynamics was well balanced with only minor changes in response to postural change while haemodynamic responses to HUT were more remarkable after parturition. In pregnant women HRV and especially its very low frequency component increased in response to HUT, whereas at 3 months after parturition the direction of these changes was opposite. Parasympathetic deactivation towards term is likely to contribute to increased heart rate and cardiac output at rest, whereas restored sympathetic modulation with modest responses may contribute stable peripheral resistance and sufficient placental blood supply under stimulated conditions. It is important to understand cardiovascular autonomic nervous system and haemodynamic control in normal pregnancy before being able to judge whether they are dysregulated in complicated pregnancies.  相似文献   
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BACKGROUND: Our objective was to investigate whether serum concentrations of asymmetric dimethylarginine (ADMA) or l-arginine correlate to hyperlipidemia or endothelial function in normal pregnancy compared with the non-pregnant subjects. METHODS AND RESULTS: As a part of population-based, prospective cohort Cardiovascular Risk in Young Finns study conducted in Finland we examined 57 pregnant Finnish women throughout gestation and 62 control women matched for age and smoking. Serum glucose, triglycerides (TG), total cholesterol (TC), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C) and ADMA, symmetric dimethylarginine (SDMA) and l-arginine were determined concomitantly with endothelium-dependent brachial artery flow-mediated dilation (FMD), measured by ultrasound. All serum lipid concentrations were significantly higher in pregnant women than in non-pregnant women (P < 0.001 for each). The mean serum ADMA concentration in pregnant women was significantly lower compared with the non-pregnant controls (0.513 micromol l(-1) +/- 0.0593 versus 0.577 micromol l(-1) +/- 0.0710, P < 0.001). Lowered ADMA concentrations did not correlate statistically to FMD in these healthy pregnant women but FMD was enhanced towards the end of pregnancy. CONCLUSIONS: ADMA and l-arginine concentrations fall in normal pregnancy despite marked hypercholesterolemia. Endothelium-dependent vasodilation is enhanced in normal pregnancy but is not statistically correlated to maternal serum ADMA or l-arginine concentrations.  相似文献   
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Microorganisms in the pregnant female genital tract are not always associated with pathology. The factors that influence the maternal response to microorganisms remain ill defined. We review the state of knowledge of microbe–host interactions in gestational tissues and highlight mechanisms that promote tolerance or pathogenesis. Tolerance to microorganisms is promoted during pregnancy by several mechanisms including upregulation of anti‐inflammatory mediators, induction of endotoxin tolerance, and possibly by regulation of autophagy. Conversely, an altered vaginal microbiota or a pre‐existing viral presence may result in induction of excessive inflammation and preterm labor. Although infections play a prevalent role in preterm birth, microbes are present in gestational tissues of women with healthy outcomes and may provide beneficial functions. The complex interactions between different microbial species and the maternal immune system during gestation remain incompletely elucidated.  相似文献   
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