Relationship of age to rat lung collagen synthesis in response to ozone exposure

We investigated the relationship of age to rat lung collagen synthesis in response to ozone (O₃) exposure. Specific pathogen-free Sprague-Dawley male rats 24, 30, 45, 60, 94, 182 and 365 days old were exposed to either 0.8 ±.05 ppm O₃ for 3 days or to 0.8 ± 0.5 ppm O₃ for 3 days followed by 4.0 ±.2 ppm O₃ for 8 hours and 60 days recovery in air. A matched number of rats from each age group received filtered air and served as controls. Lung dry weight, protein content, hydroxyproline content, ¹⁴C proline incorporation and ¹⁴C hydroxyproline formation were determined in control and exposed rat lungs. Rats exposed to 0.8 ppm O₃ for 3 days had greater dry weight, protein content, incorporation of ¹⁴C proline, and formation of ¹⁴C hydroxyproline per lung relative to controls, with the greatest changes occurring in rats older than 60 days. Rats 24 and 94 days old, exposed to 0.8 ppm O₃ for 3 days followed by 4.0 ppm O₃ for 8 hours and 60 days recovery in air, had greater lung collagen content than controls: 50% and 80%, respectively. These results suggest that collagen synthesis was increased following O₃ exposure and that the degree of change was influenced by age in the rat. Age, therefore, may be an important factor in the lung’s response to pulmonary injury.     

Differential Association Between HDL Subclasses and the Development of Type 2 Diabetes in a Prospective Study of Japanese Americans

OBJECTIVERecent studies have suggested that HDL cholesterol is inversely associated with the development of type 2 diabetes. However, little is known about the association between different HDL subclasses and the risk for future type 2 diabetes.RESULTSIn univariate analysis, total HDL and HDL2 cholesterol were inversely associated with the incidence of type 2 diabetes, but HDL3 cholesterol was not. In multivariate analysis, total HDL cholesterol (odds ratio per 1-SD increment, 0.72 [95% CI 0.52–0.995], P = 0.047) and HDL2 cholesterol (odds ratio per 1-SD increment, 0.64 [95% CI 0.44–0.93], P = 0.018) were inversely associated with the risk for type 2 diabetes independent of age, sex, BMI, waist circumference, family history of diabetes, lifestyle factors, systolic blood pressure, lipid-lowering medication use, triglyceride level, HOMA-insulin resistance, and 2-h glucose; however, HDL3 cholesterol was not associated with diabetes risk. The association between diabetes risk and total HDL and HDL2 cholesterol became insignificant after adjustment for VAT area.CONCLUSIONSSubjects with higher HDL2 cholesterol were at lower risk for incident type 2 diabetes, but this association was confounded by and not independent of VAT. Higher HDL3 cholesterol was not associated with diabetes risk.     

Attendance at specialist hepatitis clinics and initiation of antiviral treatment among persons chronically infected with hepatitis C: examining the early impact of Scotland's Hepatitis C Action Plan

Primary goals of the Hepatitis C Action Plan for Scotland Phase II (May 2008–March 2011) were to increase, among persons chronically infected with the hepatitis C (HCV) virus, attendance at specialist outpatient clinics and initiation on antiviral therapy. We evaluated progress towards these goals by comparing the odds, across time, of (a) first clinic attendance within 12 months of HCV diagnosis (n = 9747) and (b) initiation on antiviral treatment within 12 months of first attendance (n = 5736). Record linkage between the national HCV diagnosis (1996–2009) and HCV clinical (1996–2010) databases and logistic regression analyses were conducted for both outcomes. For outcome (a), 32% and 45% in the respective pre‐Phase II (before 1 May 2008) and Phase II periods attended a specialist clinic within 12 months of diagnosis; the odds of attendance within 12 months increased over time (OR = 1.05 per year, 95% CI: 1.04–1.07), but was not significantly greater for persons diagnosed with HCV in the Phase II era, compared with the pre‐Phase II era (OR = 1.1, 95% CI: 0.9–1.3), after adjustment for temporal trend. For outcome (b), 13% and 28% were initiated on treatment within 12 months of their first clinic attendance in the pre‐Phase II and Phase II periods, respectively. Higher odds of treatment initiation were associated with first clinic attendance in the Phase II (OR = 1.9, 95% CI: 1.5–2.4), compared with the pre‐Phase II era. Results were consistent with a positive impact of the Hepatitis C Action Plan on the treatment of chronically infected individuals, but further monitoring is required to confirm a sustained effect.