Editorial

No Abstrac

Retinopathy in subjects with type 2 diabetes at a tertiary diabetes clinic in Durban, South Africa: Clinical, biochemical and genetic factors

Aim: To determine the prevalence of clinical and laboratory variables and genetic polymorphisms in association with diabetic retinopathy (DR) in subjects with type 2 diabetes attending a tertiary referral diabetes clinic in Durban, South Africa. Methods: Cross-sectional study on 292 Indian and African patients with type 2 diabetes (71.5% women). The presence of DR was determined by direct ophthalmoscopy. Clinical and laboratory data were collected and polymorphisms in the NOS3 (rs61722009, rs2070744, rs1799983) and VEGF (rs35569394, rs2010963) genes were determined. Results: DR was present in 113 (39%) subjects. Those with DR were older (60.6 ± 9.6 vs. 55.4 ± 12.9 years, p = 0.005), had longer duration diabetes (18.5 ± 8.8 vs. 11.9 ± 9.2 years, p < 0.0001), higher HbA1c (9.2 ± 1.8 vs. 8.8 ± 1.7%, p = 0.049), serum creatinine (106.3 ± 90.2 vs. 75.2 ± 33.4 μmol/l), triglycerides (2.1 ± 1.2 vs. 1.9 ± 1.6 mmol/l, p = 0.042), proteinuria (72% vs. 28%, p = 0.001), and used more insulin (78% vs. 39% p = 0.0001), anti-hypertensive (95% vs. 80%, p = 0.0003) and lipid-lowering therapy (70% vs. 56%, p = 0.023). There was no association between DR and any of the NOS3 or VEGF gene polymorphisms studied, although there were ethnic differences. After adjustment, diabetes duration (OR 1.05, 95% CI 1.01–1.08), presence of proteinuria (OR 4.15, 95% CI 1.70–10.11) and use of insulin therapy (OR 3.38, 95% CI 1.60–7.12) were associated with DR. Conclusion: Hyperglycemia, duration of diabetes and proteinuria are associated with DR in Indian and African patients in South Africa, whereas NOS3 and VEGF gene polymorphisms were not associated with DR

Nickel toxicity and peroxidase activity in seedlings of Triticum aestivum L.

Ni2+ toxicity was evaluated in Triticum aestivum L. by its effects on root and shoot length, dry matter production and water content. Over a threshold value of 20 mmol m 3 Ni2+ the degree of toxicity increases as a function of the Ni2+ concentration in the medium. Ni2+-treated roots show enhanced lipid peroxidation; the higher Ni2+ treatment (40mmol m 3) also increases leakage of K+. In roots and shoots, Ni2+ enhances both guaiacol and syringaldazine extracellular peroxidase activity. The increase in extracellular peroxidase activity is also associated with an increase in the phenolic contents of roots and shoots. The observed growth inhibition might be partly the result of the effect of Ni2+ on cell turgor and cell-wall extensibility. Intracellular soluble peroxidases are also stimulated by Ni2+; such effects, independently of the substrate, were detected in extracts of Ni2+-treated shoots at a lower Ni2+ concentration than in the roots. Intracellular peroxidases might act as scavengers of peroxide radicals produced as a result of nickel toxicity

Multi-ancestry genetic study of type 2 diabetes highlights the power of diverse populations for discovery and translation.

We assembled an ancestrally diverse collection of genome-wide association studies (GWAS) of type 2 diabetes (T2D) in 180,834 affected individuals and 1,159,055 controls (48.9% non-European descent) through the Diabetes Meta-Analysis of Trans-Ethnic association studies (DIAMANTE) Consortium. Multi-ancestry GWAS meta-analysis identified 237 loci attaining stringent genome-wide significance (P &lt; 5 × 10-9), which were delineated to 338 distinct association signals. Fine-mapping of these signals was enhanced by the increased sample size and expanded population diversity of the multi-ancestry meta-analysis, which localized 54.4% of T2D associations to a single variant with &gt;50% posterior probability. This improved fine-mapping enabled systematic assessment of candidate causal genes and molecular mechanisms through which T2D associations are mediated, laying the foundations for functional investigations. Multi-ancestry genetic risk scores enhanced transferability of T2D prediction across diverse populations. Our study provides a step toward more effective clinical translation of T2D GWAS to improve global health for all, irrespective of genetic background