Effect of exercise therapy on lipid profile and oxidative stress indicators in patients with type 2 diabetes

<p>Abstract</p> <p>Background</p> <p>Yoga has been shown to be a simple and economical therapeutic modality that may be considered as a beneficial adjuvant for type 2 diabetes mellitus. This study investigated the impact of Hatha yoga and conventional physical training (PT) exercise regimens on biochemical, oxidative stress indicators and oxidant status in patients with type 2 diabetes.</p> <p>Methods</p> <p>This prospective randomized study consisted of 77 type 2 diabetic patients in the Hatha yoga exercise group that were matched with a similar number of type 2 diabetic patients in the conventional PT exercise and control groups. Biochemical parameters such as fasting blood glucose (FBG), serum total cholesterol (TC), triglycerides, low-density lipoprotein (LDL), very low-density lipoproteins (VLDL) and high-density lipoprotein (HDL) were determined at baseline and at two consecutive three monthly intervals. The oxidative stress indicators (malondialdehyde – MDA, protein oxidation – POX, phospholipase A2 – PLA2 activity) and oxidative status [superoxide dismutase (SOD) and catalase activities] were measured.</p> <p>Results</p> <p>The concentrations of FBG in the Hatha yoga and conventional PT exercise groups after six months decreased by 29.48% and 27.43% respectively (P < 0.0001) and there was a significant reduction in serum TC in both groups (P < 0.0001). The concentrations of VLDL in the managed groups after six months differed significantly from baseline values (P = 0.036). Lipid peroxidation as indicated by MDA significantly decreased by 19.9% and 18.1% in the Hatha yoga and conventional PT exercise groups respectively (P < 0.0001); whilst the activity of SOD significantly increased by 24.08% and 20.18% respectively (P = 0.031). There was no significant difference in the baseline and 6 months activities of PLA2 and catalase after six months although the latter increased by 13.68% and 13.19% in the Hatha yoga and conventional PT exercise groups respectively (P = 0.144).</p> <p>Conclusion</p> <p>The study demonstrate the efficacy of Hatha yoga exercise on fasting blood glucose, lipid profile, oxidative stress markers and antioxidant status in patients with type 2 diabetes and suggest that Hatha yoga exercise and conventional PT exercise may have therapeutic preventative and protective effects on diabetes mellitus by decreasing oxidative stress and improving antioxidant status.</p> <p>Trial Registration</p> <p>Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12608000217303</p

Effective and accurate screening for diabetic retinopathy using a 60° mydriatic fundus camera

Objectives. To establish whether an experienced endocrinologist could screen accurately for diabetic retinopathy using mydriatic 60° fundus photographs compared with a reference standard, viz. the combined highest scores of two experienced ophthalmologists. Design. Retrospective review of 60° colour transparency photographs taken over a 6-year period. Retinopathy was graded in a standardised way. Setting. Patients attending the diabetic clinic at Johannesburg Hospital, South Africa. Subjects. Fifteen hundred and seventeen patients (2 446 eyes) formed the basis for the study. Patients were included if there was more than 50% readability of the fundus photographs. Outcome measures. Outcome measures were prevalence of any retinopathy and presence of referable (severe) retinopathy. Inter-observer agreement was measured using the kappa statistic, and sensitivity and specificity of the screener were evaluated. Results. The prevalence of retinopathy at the clinic was approximately 30%, but only about 12% was severe enough to warrant referral to the ophthalmology outpatient department. The endocrinologist was very accurate in determining cases requiring referral; there was 97% agreement with the reference standard, viz. the combined highest score of two experienced ophthalmologists (gold standard). Correlation on the determination of any retinopathy was less accurate (80% agreement), mostly owing to the endocrinologist reporting more isolated microaneurysms than the ophthalmologists. The screening method used gave a sensitivity of 83% and specificity of 99% which are within recommended standards. Conclusions. The screening strategy using a mydriatic fundus camera at the diabetic clinic was found to be effective and accurate and greatly reduced the number of possible referrals to the ophthalmology outpatient department. JEMDSA Vol.10(1) 2005: 11-1

Effective and accurate screening for diabetic retinopathy using a 60º mydriatic fundus camera

Objectives. To establish whether an experienced endocrinologist could screen accurately for diabetic retinopathy using mydriatic 60° fundus photographs compared with a reference standard, viz. the combined highest scores of two experienced ophthalmologists. Design. Retrospective review of 60° colour transparency photographs taken over a 6-year period. Retinopathy was graded in a standardised way. Setting. Patients attending the diabetic clinic at Johannesburg Hospital, South Africa. Subjects. Fifteen hundred and seventeen patients (2 446 eyes) formed the basis for the study. Patients were included if there was more than 50% readability of the fundus photographs. Outcome measures. Outcome measures were prevalence of any retinopathy and presence of referable (severe) retinopathy. Interobserver agreement was measured using the kappa statistic, and sensitivity and specificity of the screener were evaluated. Results. The prevalence of retinopathy at the clinic was approximately 30%, but only about 12% was severe enough to warrant referral to the ophthalmology outpatient department. The endocrinologist was very accurate in determining cases requiring referral; there was 97% agreement with the reference standard, viz. the combined highest score of two experienced ophthalmologists (gold standard). Correlation on the determination of any retinopathy was less accurate (80% agreement), mostly owing to the endocrinologist reporting more isolated microaneurysms than the ophthalmologists. The screening method used gave a sensitivity of 83% and specificity of 99% which are within recommended standards. Conclusions. The screening strategy using a mydriatic fundus camera at the diabetic clinic was found to be effective and accurate and greatly reduced the number of possible referrals to the ophthalmology outpatient department. S Afr Med J 2005; 95: 57-61

Three-dimensional structure of lipoamide dehydrogenase from Pseudomonas fluorescens at 2.8 A resolution. Analysis of redox and thermostability properties

The structure of Pseudomonas fluorescens lipoamide dehydrogenase, a dimeric flavoenzyme with a molecular mass of 106,000 daltons, was solved by the molecular replacement method and refined to an R-factor of 19.4% at 2.8 A resolution. The root-mean-square difference from ideal values for bonds and angles is 0.019 A and 3.8 degrees, respectively. The structure is closely related to that of the same flavoprotein from Azotobacter vinelandii. The root-mean-square difference for 932 C alpha atoms is 0.64 A, with 84% sequence identity. The residues in the active site are identical, while 89% of the interface residues are the same in the two enzymes. A few structural variations provide the basis for the differences in thermostability and redox properties between the two homologous proteins. Particularly, in the A. vinelandii molecule a threonine to alanine (T452A) mutation leaves a buried carbonyl oxygen, located at the subunit interface and in proximity of the flavin ring, unpaired to any H-bond donor, probably providing an explanation for the lower stability of the A. vinelandii enzyme with respect to the P. fluorescens enzyme. Six surface loops, which previously could not be accurately positioned in the A. vinelandii structure, are well defined in P. fluorescens lipoamide dehydrogenase. On the basis of the P. fluorescens structure, the six loops could be correctly defined also in the A. vinelandii enzyme. This is an unusual case where similar refinement methodologies applied to two crystal forms of closely related proteins led to electron density maps of substantially different quality. The correct definition of these surface residues is likely to be an essential step for revealing the structural basis of the interactions between lipoamide dehydrogenase and the other members of the pyruvate dehydrogenase multienzyme complex