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It is widely recognized that polyester (PET) fibers with swelling properties are necessary for advanced applications of PET fibers in waterproof fabrics. This study presented the UV‐initiated methods to graft polyacrylamide (PAM) hydrogel on the surface of PET fibers. In the one‐step method, PET fibers are impregnated with a mixed solution of the photoinitiator benzophenone (BP) and the monomer acrylalkylamine (AM). Then, the PET fiber was directly exposed to UV light. In the two‐step method, PET fibers were first impregnated with a photoinitiator solution to generate BP radicals. Then, the fibers impregnated with a monomer solution before being grafted by UV light. Both two methods ultimately achieve PAM gelation‐modified PET fibers. The chemical composition and surface structure were detected by Fourier transform infrared spectroscopy and scanning electron microscope. The findings demonstrate that the PAM hydrogel was successfully grafted on the PET fibers through one‐step method or a two‐step method. In addition, the properties of the grafted PET fibers were evaluated by grafting yield, contact angle, and swelling test. The study indicated that the modified PET fibers via a two‐step method exhibited a superior grafting yield up to 29.3% (PET‐2n) and 54% (PET‐2) compared to the one‐step technique (PET‐1). It was shown that the grafting efficacy of PET fibers modified by two‐step method is better than one‐step method. The static contact angles of PET fibers by UV‐Induced were all reduced. For instance, the contact angles of PET‐2n were decreased from 115° to 62.9°; and the two‐step modified PET fiber after acetone cleaning (PET‐2) decreased from 115° to 60°. It was suggested that the hydrophilicity of the modified PET fibers significantly increased. In addition, the research shows that the gelation‐modified fibers were all possessed swelling properties. [ABSTRACT FROM AUTHOR]

Background Metabolic syndrome is often beneficial from testosterone replacement therapy. Although testosterone and sex hormone-binding globulin (SHBG) are inversely associated with the risk of metabolic syndrome, it is controversial whether the association between testosterone and metabolic syndrome is independent of SHBG. Methods Testosterone, SHBG and metabolic syndrome were evaluated in 2361 men aged 20-73 years, who participated in the population-based Fangchenggang Area Male Health and Examination Survey. Total testosterone, SHBG and other biochemical profiles were measured. Free testosterone and bioavailable testosterone were calculated on the basis of Vermeulen's formula. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria for Asian population. The independent associations with metabolic syndrome were determined by multivariate logistic regression analysis. Results Men with metabolic syndrome had a lower level of total testosterone, bioavailable testosterone, free testosterone, or SHBG than those without metabolic syndrome (all p < 0.001). Both total testosterone and SHBG were inversely correlated with body mass index or homeostasis model assessment of insulin resistance (all age-adjusted p < 0.001). Men within the lowest quartile of total testosterone [odds ratio (OR) = 4.86, 95% confidence interval (CI) = 2.72-8.68], bioavailable testosterone (OR = 3.04, 95% CI = 1.81-5.10), free testosterone (OR = 3.08, 95% CI = 1.81-5.27) or SHBG (OR = 4.28, 95% CI = 2.52-7.27) had a risk of metabolic syndrome after adjusting for age, smoking, homeostasis model assessment of insulin resistance and body mass index. Total testosterone remained inversely associated with metabolic syndrome after further adjusting for SHBG (OR = 0.95, 95% CI = 0.92-0.99), while SHBG remained inversely associated with metabolic syndrome after further adjusting for total testosterone (OR = 0.99, 95% CI = 0.97-1.00). Conclusion Total testosterone and SHBG are independent risk factors of metabolic syndrome. Prospective studies are needed to explore whether the association between sex hormones and metabolic syndrome was mediated by insulin resistance or obesity. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective To examine the association of endogenous sex hormones and sex hormone-binding globulin (SHBG) with C-reactive protein ( CRP) in Chinese men. Design and participants The study population comprised 1989 men at baseline recruitment of a population-based cohort in China. Participant information on risk factors was collected by a face-to-face interview and clinical examination. All subjects in the study were without taking any kind of medication for anti-inflammation purpose or treatment of hypogonadism and with CRP value less than 10 mg/l. Data were analysed using linear regression analyses. Results Higher levels of total testosterone ( TT, β = −0·114, 95% CI, −0·162 to −0·065), free testosterone (β = −0·059, 95% CI, −0·106 to −0·012) and SHBG (β = −0·116, 95% CI, −0·169 to −0·063) were statistically significantly related to lower levels of CRP, after adjustment for age, waist circumference ( WC), triglycerides, high-density lipoprotein cholesterol, fasting glucose, insulin, smoking status, hypertension, diabetes and family history of hypertension or diabetes. In the subgroup of men with body mass index ≥ 27·5 kg/m2 or with metabolic syndrome, findings for TT and SHBG were more pronounced, whereas the associations of TT with CRP were attenuated and nonstatistically significant among subjects with WC ≥ 90 cm or with insulin resistance. No associations were observed between estradiol, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and CRP. Conclusions We have confirmed the association of androgens with reduced inflammation as measured by CRP in Chinese men. This is independent of conventional cardiovascular risk factors and is explained in part by markers of central obesity and insulin resistance, rather than metabolic syndrome. [ABSTRACT FROM AUTHOR]