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Background: The relationship between vitamin D insufficiency and cognitive impairment remains equivocal in Asians. We examined the association between circulating 25-hydroxyvitamin D (25OHD) concentration and cognitive performance in a large multi-ethnic Singaporean population-based study. We also conducted a meta-analysis of 25OHD concentrations amongst cognitively impaired older adults in Asia.Methods: Our population-based cross-sectional study included 2273 persons ≥60 years of age from the Singapore Epidemiology of Eye Diseases (SEED) study (mean ± SD age 70.4 ± 6.2 years; 44.7% female), who were categorized according to 25OHD concentration (i.e. ≤10, 10.1-20 and >20 ng mL(-1) ). The 25OHD concentration was measured and adjusted to reflect a deseasonalized value. Cognition was assessed using the total and domain scores of the Abbreviated Mental Test (AMT). Global cognitive impairment was defined as AMT score of ≤6 if 0-6 years of education and AMT score of ≤8 if >7 years of education. Fully adjusted multivariate models were used. We included seven studies in a meta-analysis of 25OHD and cognition in Asia (6068 participants; 1179 cognitively impaired cases).Results: Participants with 25OHD levels >20 ng mL(-1) (n = 1302) had higher AMT total scores (mean ± SD 8.5 ± 1.9) and were less likely to have cognitive impairment (14.1%) than participants with lower 25OHD levels (overall P < 0.001, P-trend < 0.001). Deseasonalized 25OHD concentration was associated with AMT score (β = 0.10 per 10 ng mL(-1) , P = 0.035). Vitamin D insufficiency (25OHD ≤20 ng mL(-1) ) was associated with global cognitive impairment (OR 1.56, P = 0.028). Specifically, 25OHD concentration correlated with semantic memory (r = 0.08, P = 0.009) and orientation in time (r = 0.09, P = 0.003). In the meta-analysis, the pooled mean 25OHD difference was -6.83 ng mL(-1) (95% confidence interval -11.36; -2.30), indicating lower 25OHD concentrations amongst cognitively impaired compared to cognitively healthy participants in Asia.Conclusion: Vitamin D insufficiency is associated with a greater likelihood of and more severe cognitive impairment in Asian populations. [ABSTRACT FROM AUTHOR]

The article offers information on the link between recurrent Gestational diabetes mellitus (GDM) and the subsequent development of postpartum cardiovascular diseases (CVD). It discussed the increased risks of long-term health problems after delivery like type 2 diabetes and CVD and also mentions the woman's most recent GDM episode and postpartum retinal microvascular dysfunction.

Aim To examine the relationships of serum markers of inflammation and endothelial function to diabetic retinopathy. Methods We recruited 224 patients with diabetes (85 with Type 1 and 139 with Type 2 diabetes) aged 18-70 years. Serum markers of inflammation (high-sensitivity C-reactive protein) and endothelial function (soluble intercell adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, endothelin-1 and total nitrite) were assessed using nephelometry, immunoassays and spectroscopy. Diabetic retinopathy was graded from two-field fundus photographs according to the Airlie House Classification system and was categorized into no diabetic retinopathy, mild non-proliferative diabetic retinopathy, moderate non-proliferative diabetic retinopathy and vision-threatening diabetic retinopathy, the latter comprising severe non-proliferative diabetic retinopathy, proliferative diabetic retinopathy or clinically significant macular oedema. Multinomial logistic regression was used to assess the associations between serum markers and diabetic retinopathy. Results In the study, 64% of patients (144/224) had diabetic retinopathy and 25% (57/244) had vision-threatening diabetic retinopathy. After controlling for age, gender, diabetes duration, HbA1c, systolic blood pressure, total and HDL cholesterol, smoking, the use of insulin or oral hypoglycaemic agents, nephropathy and cardiovascular disease, a positive association was found between increasing high-sensitivity C-reactive protein levels and the presence of vision-threatening diabetic retinopathy (odds ratio 1.26; 95% CI 1.05-1.51, per sd increase in high-sensitivity C-reactive protein). After stratifying by BMI ( ≥ 30 and < 30 kg/m2), this association was found to be more pronounced in people with a BMI ≥ 30 kg/m2 (odds ratio 2.9; P for interaction = 0.019). No associations were found between serum markers of endothelial activation and diabetic retinopathy. Conclusions Higher C-reactive protein levels, but not markers of endothelial function, may be related to more severe diabetic retinopathy. This finding suggests that inflammatory processes are involved in severe diabetic retinopathy, particularly in patients with a BMI ≥ 30 kg/m2. [ABSTRACT FROM AUTHOR]

Objective Previous studies examining the association between genetic variations in prostaglandin pathway and risk of head and neck cancer ( HNC) have only included polymorphisms in the PTGS2 ( COX2) gene. This study investigated the association between genetic polymorphisms of six prostaglandin pathway genes ( PGDS, PTGDS, PTGES, PTGIS, PTGS1 and PTGS2), and risk of HNC. Methods Interviews regarding the consumption of alcohol, betel quid, and cigarette were conducted with 222 HNC cases and 214 controls. Genotyping was performed for 48 tag and functional single-nucleotide polymorphisms ( SNPs). Results Two tag SNPs of PTGIS showed a significant association with HNC risk [rs522962: log-additive odds ratio ( OR) = 1.42, 95% confidence interval ( CI): 1.01-1.99 and dominant OR = 1.58, 95% CI: 1.02-2.47; rs6125671: log-additive OR = 1.49, 95% CI: 1.08-2.05 and dominant OR = 1.96, 95% CI: 1.16-3.32]. In addition, a region in PTGIS tagged by rs927068 and rs6019902 was significantly associated with risk of HNC (global P = 0.007). Finally, several SNPs interacted with betel quid and cigarette to influence the risk of HNC. Conclusions Genetic variations in prostaglandin pathway genes are associated with risk of HNC and may modify the relationship between use of betel quid or cigarette and development of HNC. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration ( AMD) is a common vision-threatening condition affecting the elderly. AMD shares common risk factors and processes, including vascular and inflammatory pathways, with many systemic disorders. Associations have been reported between AMD and hypertension, cardiovascular disease, cerebrovascular disease, dyslipidaemia, chronic kidney disease and neurodegenerative disorders. An increasing amount of evidence suggests that individuals with AMD are also at risk of systemic diseases such as stroke. In this review, we summarize the latest evidence to support the notion that AMD is an ocular manifestation of systemic disease processes, and discuss the potential systemic side effects of ocular AMD therapy of which general physicians should be aware. Recent genetic discoveries and understanding of the pathogenic pathways in AMD in relation to systemic disorders are also highlighted. [ABSTRACT FROM AUTHOR]

Objective Type 2 diabetes and associated complications adversely affect health-related quality of life ( HRQo L). However, it is unclear whether different complications have the same or different associations with HRQo L. We examined associations between retinopathy, nephropathy, peripheral neuropathy (microvascular), coronary heart disease, stroke and peripheral arterial disease (macrovascular) in diabetes and HRQo L. Design This study was a follow-up examination between 2004 and 2007 of participants from four previous cross-sectional population-based studies in Singapore. Methods Health-related quality of life was assessed through self-administered SF-36 health survey version 2. Diabetes and complications status were assessed through self-report, clinical and laboratory examinations. About 2601 individuals, 2205 healthy and 396 with diabetes, were studied. Results Lower physical component scores ( PCS) were associated with microvascular (2·96 points, P < 0·001) and both macro- and microvascular complications (4·67 points, P < 0·001), but not diabetes alone. Coronary heart disease (3·86 points, P = 0·007), peripheral neuropathy (11·46 points, P < 0·001) and severe retinopathy (4·46 points, P < 0·001) were associated with lower PCS. The greatest reduction in scores was seen in peripheral neuropathy. Conclusions Quality of life in patients with diabetes is affected mainly by presence of complications, and not diabetes per se. Peripheral neuropathy was associated with the greatest reduction in quality of life. Improved management to prevent or delay onset of complications may reduce the effect on quality of life in patients with diabetes. [ABSTRACT FROM AUTHOR]

Aim To investigate the frequency and risk factors of non-retinopathy ocular conditions in persons with diabetes. Methods A population-based cross-sectional study of 3176 Malay persons aged between 40 and 79 years in Singapore was conducted. Cataract, glaucoma, refractive errors, age-related macular degeneration, dry eye, epiretinal membrane, ocular hypertension and retinal conditions were assessed based on standardized interviews, clinical examinations and laboratory investigations. Results A total of 768 participants (24.2%) had diabetes. People with diabetes were more likely to have cortical cataract (52.1 vs. 37.3%, P < 0.001), ocular hypertension (10.9 vs. 7.4%, P = 0.002) and epiretinal membrane (17.2 vs. 10.1%, P < 0.001) compared with those without diabetes. The odds of having cortical cataract (odds ratio 1.63, 95% CI 1.20-2.20) and epiretinal membrane (among those with previous cataract surgery: odds ratio 1.63, 95% CI 1.20-2.20) were significantly higher in people with diabetes compared with those without. The population attributable risks for cortical cataract and epiretinal membrane because of diabetes were 8.7 and 9.0%, respectively. In persons with diabetes, hypertension and high cholesterol were the major risk factors associated with non-retinopathy eye complications such as ocular hypertension (odds ratio 1.18, 95% CI 1.04-1.33) and retinal emboli (odds ratio 1.99, 95% CI 1.05-3.80). Conclusion Our results allow clinicians to better inform patients with diabetes that they are more likely to have cortical cataract and epiretinal membranes (those with previous cataract surgery) in addition to diabetic retinopathy. Two modifiable risk factors-blood pressure and cholesterol associated with ocular hypertension and retinal emboli, respectively-are also risk factors for non-retinopathy ocular conditions in persons with diabetes. [ABSTRACT FROM AUTHOR]

Aims: It is common for refraction to be measured using different testing methods in children, with much debate still ongoing on the preferred method. Therefore, we compared cycloplegic refraction measurements using three objective methods in a large cohort of children. Methods: We present the findings from a total of 51 children who were recruited and examined as part of the Strabismus, Amblyopia and Refractive error in Singapore preschool children (STARS) study. Each child underwent a comprehensive eye examination, which included cycloplegic refraction using a hand-held autorefractor (Retinomax), a table mounted autorefractor (Canon FK-1) and streak retinoscopy. Spherical equivalent (SE) was calculated as (sphere + half of minus cylinder) and astigmatism was determined using the negative cylindrical component. Results: The current study sample consisted of 29 boys and 22 girls aged between 24 and 72 months (mean age 52.3 months). The mean spherical equivalent (SE) using the table-mounted autorefractor (1.03 ± 1.64 D) was not significantly different from the streak retinoscopy (1.09 ± 1.58 D, p = 0.66). However, the mean SE using the hand-held Retinomax (0.80 ± 1.43 D) was significantly different (more ‘minus’ p = 0.0004) to streak retinoscopy. The astigmatism measured using the hand held (−0.89 ± 0.51 D) and table-mounted autorefractor (−0.83 ± 0.61 D) were significantly greater than that obtained with streak retinoscopy (−0.58 ± 0.56, p = 0.0003). Conclusions: The table-mounted autorefractor provided a reading more similar to that of streak retinoscopy than to that of the hand-held autorefractor. However, there were only small differences in mean SE (<0.32 D) between the hand-held Retinomax and the other methods, which will have implications in research investigations of refractive error. [ABSTRACT FROM AUTHOR]

Aims To assess the proportion of patients who had diabetes and hypertension with optimal blood pressure (BP) control and to describe patients’ awareness of the importance of BP control. Methods A cross-sectional survey of out-patients with diabetes who attended the Royal Victorian Eye and Ear Hospital (Melbourne, Australia) was conducted between October 2006 and February 2007. Of 245 patients invited, 220 (90%) participated. Optimal BP control was defined as BP < 130/80 mmHg recorded at the latest visit; proportions of patients with awareness of BP control were defined non-exclusively by: (i) ability to recall a previous BP record and rate the appropriateness of that BP level; (ii) ability to recall the recommended optimal BP control level by current diabetes management guidelines; (iii) knowledge that optimal BP control is important to diabetes management; and (iv) knowledge that optimal BP control is important to eye health. Results Of the 220 patients, 176 had both diabetes and hypertension. Of these, 49 of 176 (28%) had BP controlled optimally, and 30 of 176 (17%) recalled and rated a previous recorded BP level appropriately. Fewer than one in four (22%) acknowledged the recommended optimum BP level of < 130/80 mmHg, fewer than one in two (48%) rated BP as important to diabetes management, and one in three (35%) rated BP control as important to eye health. Conclusions In this sample of patients with diabetes and hypertension, fewer than one-third achieved the BP level recommended by clinical guidelines, and fewer than half were aware of the importance of BP control. [ABSTRACT FROM AUTHOR]

Retinal vein occlusion (RVO) is the second most common retinal vascular disease after diabetic retinopathy and is a common cause of visual morbidity and blindness in the elderly. A large proportion of patients with RVO have a history of cardiovascular disease, hypertension, diabetes mellitus or open-angle glaucoma. Although RVO is sometimes associated with thrombophilias and coagulation abnormalities, the role of coagulation factors in the development of RVO remains unclear. This review did not find strong evidence to support an extensive work-up for thrombophilic and coagulation diseases for the vast majority of patients. However, when tests for common cardiovascular risk factors for RVO are negative, evaluation for potential coagulation disorders may be indicated, particularly in young patients and in patients with bilateral RVO, a history of previous thromboses or a family history of thrombosis. [ABSTRACT FROM AUTHOR]

Summary Deinococcus radiodurans is highly resistant to radiation and mutagenic chemicals. Mutants defective in the putative glucose-6-phosphate dehydrogenase gene (zwf – ) and the aldolase gene (fda – ) were generated by homologous recombination. These mutants were used to test the cells’ resistance to agents that cause dimer formation and DNA strand breaks. The zwf – mutants were more sensitive to agents that induce DNA excision repair, such as UV irradiation and H2 O2 , but were as resistant to DNA strand break-causing agents such as methylmethanesulphonic acid (MMS) and mitomycin C (MMC) as the wild-type cells. Analysis of the cytoplasmic fraction of zwf – cells showed that the concentrations of inosine monophosphate (IMP) and uridine monophosphate (UMP) were only 30% of those found in the wild-type cells. The fda – mutants were slightly more resistant to UV light and H2 O2 . Results suggested that the deinococcal pentose phosphate pathway augmented the DNA excision repair system by providing cells with adequate metabolites for the DNA mismatch repair. [ABSTRACT FROM AUTHOR]

Background: Reciprocal creatinine plot is often used to monitor patients with progressive renal insufficiency and to predict the onset of dialysis, although the latter practice has not been validated.Objective: We examined whether extrapolating the reciprocal creatinine plot can predict the onset of dialysis.Setting: Single centre study in the dialysis unit of a University teaching hospital.Design: We studied 170 consecutive patients with progressive renal insufficiency referred to a single nephrology unit and subsequently dialysed. Reciprocal creatinine plot was constructed by all available serum creatinine values before dialysis (the 'definitive plot'). Four 'interim plots' were constructed for each patient by using serum creatinine below 400, 500, 600 and 700 micromol L(-1). Interim plots with at least five points and Pearson's r > 0.9 were analysed. The date of dialysis was predicted from the least squares linear regression formula and a target serum creatinine level cor- responding to estimated creatinine clearance of 7 mL min-1, at which dialysis was recommended.Results: The median duration of observation was 25 months. After serum creatinine 500 micromol L(-1), the slope of the interim plot remained stable and extrapolation was possible in 117 patients (68.8%). However, the limits of agreement for predicting the onset of dialysis were wide (from -11.7 to +9.5 months). At this creatinine level, the onset of dialysis fell within 1 month of the predicted onset in only 41 patients (24.1%). The limits of agreement for prediction narrowed when time points of higher serum creatinine were included into the plot. However, nine patients (5.3%) required dialysis within 1 month at creatinine 600 micromol L(-1) and the dialysis was not predicted by the reciprocal creatinine plot. Target serum creatinine did not correlate with acute serum creatinine at which dialysis was started (r = 0.051, P = 0.51). A slower decline in renal function was associated with a higher prediction error (r = 0.212, P = 0.014).Conclusions: The onset of dialysis cannot be predicted by extrapolation of the reciprocal creatinine plot because of individual variation in the renal function that require dialysis. Dialysis would be almost imminent in some patients by the time serum creatinine reaches a level that allows accurate construction and extrapolation of a plot. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Retinopathy in subjects with impaired fasting glucose: The NANSY-Eye baseline report," by M. Tyrberg and colleagues in the previous issue.

A letter to the editor is presented regarding diabetic retinopathy accompanied with an increased incidence of cardiovascular disease in Type 2 diabetic patients.

The capability of Selenastrum capricornutum to activate o-phenylenediamine (OPD) and 2-aminofluorene (2-AF) was tested in a modified Amesassay in which the activation component (S9) was replaced by the algal cells. Normal-grown algae did not activate OPD but these cells activated 2-AF by sixfold. Copper induces a peroxidase in S. capricornutum. Algae pregrown on copper-enriched medium increased the mutagenicity of OPD by more than 16-fold, but these cells failed to further activate 2-AF. However, 2-AF was further activated by algae pretreated with flavone, Aroclor, 5,6-naphthoflavone, or 2,4-dichlorophenoxyacetic acid, but not lindane or ethanol. This suggested that a cytochrome P450 system was involved in 2-AF activation. Coincubating algae with cytochrome P450 inhibitors including diethyldithiocarbamate, methimizole, or acetaminophen, but not catechin, 7-8-naphthoflavone, or CuCl2 reduced the activation level of 2-AF significantly. [ABSTRACT FROM AUTHOR]

Benzamines are the major aromatic amines used in industry and can also be released from azo dyes, which are widely used in the textile, paper-making, and food industries. The toxicity of 10 benzamines was tested by the well diffusion assay technique against 18 common bacterial species including the nitrogen-fixing bacterium Azotobacter vinelandii. p-Phenylenediamine was found to be inhibitory to the growth of Aeromonas hydrophila and Pseudomonas fluorescens. o- Phenylenediaminewas inhibitory to Escherichia coli, Klebsiella pnemoniae, Salmonellaenteritidis, and Shigella sonnei. 2,5-Diaminotoluene was inhibitory to the growth of P. fluorescens and Streptococcus mitis. The growth of A, vinelandii was inhibited by p-phenylenediamine and 2,5-diaminotoluene in the well diffusion assay. p-Nitroaniline was also found to be inhibitory to the growth of A. vinelandii in Burk's nitrogen-free medium. The nitrogenase activity of A. vinelandii was inhibited by p-phenylenediamine, 2,5-diaminotoluene, p-nitroaniline, 2-nitro-p-phenylenediamine, 3-nitro-o-phenylenediamine, and 4-nitro-o-phenylenediamine. Because many of these organisms are common soil and aquatic bacteria, the accumulation of these benzamine compounds in the environment may have an adverse impact on soil biochemical activities. [ABSTRACT FROM AUTHOR]

Benzidine and benzidine analogues are mutagenic and carcinogenic metabolites of azo dyes that are widely found in the environment. The toxicities of benzidine and nine of its analogues against 18 bacterial strains including nitrogen-fixing Azotobacter vinelandii were tested using the well diffusion assay technique. 2-Aminobiphenyl and 3-aminobiphenyl were the most inhibitory to all bacterial species tested except A. vinelandii. 4-Aminobiphenyl was inhibitory to the growth of A.vinelandii using a plate count assay, although it failed to show an inhibitory effect in the well diffusion assay. 3,3'-4,4'- Tetraaminobiphenyl was inhibitory to both A. vinelandii and Aeromonas hydrophila, whereas benzidine, 3,3'-dimethoxybenzidine, 4,4'-dinitro-2-biphenylamine, 3,3'-5,5'-tetramethylbenzidine, N,N-N',N'-tetramethylbenzidine, and o-tolidine were not inhibitory to any of the bacterial species tested. Of all these compounds tested, only 3,3'-4,4'-tetraaminobiphenyl and 4-aminobiphenyl inhibited the nitrogenase activity of A. vinelandii. [ABSTRACT FROM AUTHOR]