Smoking and Risk of Kidney Failure in the Singapore Chinese Health Study

Background:The relationship between smoking and risk of kidney failure, especially in people of Chinese origin, is not clear. We analyzed data from the Singapore Chinese Health Study to investigate whether smoking increases the risk of kidney failure.Methods:The Singapore Chinese Health Study is a population-based cohort of 63,257 Chinese adults enrolled between 1993 and 1998. Information on smoking status was collected at baseline. Incidence of kidney failure was identified via record linkage with the nationwide Singapore Renal Registry until 2008. Kidney failure was defined by one of the following: 1) serum creatinine level of more than or equal to 500 μmol/l (5.7 mg/dl), 2) estimated glomerular filtration rate of less than 15 ml/min/1.73 m2, 3) undergoing hemodialysis or peritoneal dialysis, 4) undergone kidney transplantation. Cox proportional hazard regression analysis was performed for the outcome of kidney failure after adjusting for age, education, dialect, herbal medications, body mass index, sex, physician-diagnosed hypertension and diabetes mellitus.Results:The mean age of subjects was 55.6 years at baseline, and 44% were men. Overall 30.6% were ever smokers (current or former) at baseline. A total of 674 incident cases of kidney failure occurred during a median follow-up of 13.3 years. Among men, smokers had a significant increase in the adjusted risk of kidney failure [hazard ratio (HR): 1.29; 95% CI: 1.02-1.64] compared to never smokers. There was a strong dose-dependent association between number of years of smoking and kidney failure, (p for trend = 0.011). The risk decreased with prolonged cessation (quitting ≥10 years since baseline). The number of women smokers was too few for conclusive relationship.Limitation:Information on baseline kidney function was not available.Conclusions:Cigarette smoking is associated with increased risk of kidney failure among Chinese men. The risk appears to be dose- and duration-dependent and modifiable after long duration of cessation. © 2013 Jin et al

Experimental characterisation on the behaviour of PLLA for stretch blowing moulding of bioresorbable vascular scaffolds

Processing tubes from poly (l-lactic acid) (PLLA) by stretch blow moulding (SBM) is used in the manufacture of bioresorbable vascular scaffolds (BVS) to improve their mechanical performance. To better understand this processing technique, a novel experimental setup by free stretch blow inside a water bath was developed to visualise the tube forming process and analyse the deformation behaviour. PLLA tubes were heated, stretched and blown with no mould present inside a temperature-controlled water bath whilst recording the processing parameters (axial force, inflation pressure). The onset of pressure activation relative to the axial stretch was controlled deliberately to produce a simultaneous (SIM) or sequential (SEQ) mode of deformation. Real-time images of the tube during forming were captured using high speed cameras and the surface strain of the patterned tube was extracted using digital image correlation (DIC). The deformation characteristics of PLLA tubes in SBM was quantified by analysis of shape evolution, strain history and stress-strain relationship

Biochemical and structural characterization of mycobacterial aspartyl-tRNA synthetase AspS, a promising TB drug target.

The human pathogen Mycobacterium tuberculosis is the causative agent of pulmonary tuberculosis (TB), a disease with high worldwide mortality rates. Current treatment programs are under significant threat from multi-drug and extensively-drug resistant strains of M. tuberculosis, and it is essential to identify new inhibitors and their targets. We generated spontaneous resistant mutants in Mycobacterium bovis BCG in the presence of 10× the minimum inhibitory concentration (MIC) of compound 1, a previously identified potent inhibitor of mycobacterial growth in culture. Whole genome sequencing of two resistant mutants revealed in one case a single nucleotide polymorphism in the gene aspS at 535GAC>535AAC (D179N), while in the second mutant a single nucleotide polymorphism was identified upstream of the aspS promoter region. We probed whole cell target engagement by overexpressing either M. bovis BCG aspS or Mycobacterium smegmatis aspS, which resulted in a ten-fold and greater than ten-fold increase, respectively, of the MIC against compound 1. To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. Finally, to aid hit-to-lead optimization, the crystal structure of apo M. smegmatis AspS was determined to a resolution of 2.4 Å

Consequences of accelerated weathering in polylactide nanocomposites reinforced with halloysite nanotubes

The purpose of this study was to explore consequences of accelerated weathering on the behavior of polylactide/halloysite nanotube composites. Nanocomposites were compounded by melt mixing method via a twin-screw extruder while specimens for testing and analyses were shaped by injection molding. Behaviors of the specimens were compared before weathering and after exposure to UV irradiation and humidity steps according to Cycle-C of ISO 4892-3 standards for a total duration of 300h. IR studies revealed that photolysis and partly hydrolysis were the main degradation mechanisms leading to random main chain scission of the PLA macromolecular structure, which was reflected with drastic reductions both in the molecular weight of PLA and the mechanical properties of flexural strength and fracture toughness. On the other hand, no significant reductions were observed in the values of thermal degradation temperatures, storage modulus and flexural modulus of the specimens, which was due to the compensating effect of higher amounts of crystallinity formed during UV irradiation cycles at 70?

Three-year outcome of phase-specific early intervention for first-episode psychosis: A cohort study in Hong Kong

Aim: Although phase-specific early intervention for first-episode psychosis has been implemented in many different parts of the world, limited medium-term outcome data are available in non-Western populations with relatively low mental health resources. The study aimed to determine the effectiveness of phase-specific early intervention in first-episode psychosis. Method: In this cohort study, we compared the 3-year outcome of 700 first-episode psychosis patients who received phase-specific early intervention with that of 700 patients matched for age, sex and diagnosis who received standard psychiatric care prior to early intervention. Using a structured data acquisition procedure, we determined functional outcome, symptom levels, relapse, recovery, suicidal behaviour and service utilization from clinical records. Results: Patients in the early intervention group had longer full-time employment or study (P<0.001), fewer days of hospitalization (P<0.001), less severe positive symptoms (P=0.006), less severe negative symptoms (P=0.001), fewer suicides (P=0.009) and fewer disengagements (P=0.002) than the historical control group. Additionally, more patients in the early intervention group experienced a period of recovery (P=0.001), but the two groups had similar rates of relapse (P=0.08) and durations of untreated psychosis (P=0.72). Conclusions: The 3-year outcome in phase-specific early intervention compared favourably with that of standard psychiatric care, particularly with respect to functional outcome and reduction in hospitalizations, suicides and disengagements. However, intervention did not appear to reduce the rate of relapse. © 2011 Blackwell Publishing Asia Pty Ltd.link_to_subscribed_fulltex

Three-year outcome of phase-specific early intervention for first-episode psychosis: a cohort study in Hong Kong.

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