No abstract

ICA PI is comparable with femPWV in its association with cardiovascular disease. PI does not improve the prediction of IHD over age and systolic blood pressure.

We have investigated the possibility that post-translational modification of myosin by protein glycosylation and cross-linking occurs in cardiac myosin. Left ventricular muscle was obtained at post-mortem from 6 diabetic and 7 non-diabetic subjects. Myosin was extracted from muscle and purified using Sephadex chromatography followed by protein concentration. Glycosylation was estimated using boronate affinity chromatography with the myosin dissolved in a pyrophosphate buffer, the glycosylated myosin being displaced with sorbitol. Cross-linkage was assessed by fluorescence at 440 nm upon excitation at 370 nm. Diabetic subjects had significantly higher levels (p less than 0.02) of glycosylated myosin (median 6.0% (range 3.8-6.6%] than non-diabetic subjects (median 2.4% (range 0.3-4.2%] but there was no difference in the degree of cross-linkage as assessed by fluorescence (diabetic median 9.8 (range 6.5-17.0) arbitrary units; non-diabetic median 9.7 (range 6.0-11.4) arbitrary units). Glycosylation of left ventricular myosin may be of relevance to the excess risk of congestive cardiac failure in diabetic patients.

There are conflicting reports of platelet function abnormalities in diabetic patients without vascular complications. We have studied in vitro platelet aggregation, using platelet rich plasma and whole blood techniques, in 18 patients with uncomplicated insulin-dependent diabetes and a matched group of 24 non-diabetic subjects. In addition we measured plasma beta-thromboglobulin levels in these groups, as an index of in vivo platelet activation, and compared the indices of in vitro and in vivo platelet function before and after maximal bicycle exercise. Before exercise plasma beta-thromboglobulin levels and platelet sensitivities to ADP, collagen or adrenaline, as assessed by both methods of platelet aggregation, were the same in diabetic and control subjects. Both groups showed similar increases in beta-thromboglobulin levels and in platelet sensitivity to all agonists in whole blood following exercise. Using platelet rich plasma there were no changes in platelet sensitivity in either group after exercise. In non-diabetic subjects, increases in noradrenaline levels after exercise correlated with increases in platelet sensitivity to adrenaline in whole blood. This was not observed in the diabetic group. Abnormalities of platelet function, using the techniques described here, are not present in diabetic patients who do not have clinical evidence of vascular disease.

Baseline CCA obtained from standard MRI protocols may be compared with subsequent MRI examinations as a surrogate for neurodegeneration and cerebral atrophy in patients with MS. This study demonstrates an association between CCA and disability in individuals presenting with CIS who convert to MS.