Endothelial cell oxidative stress in diabetes: a key driver of cardiovascular complications?

Atherothrombotic disease is a well-recognized complication of diabetes and is a major contributor to the high morbidity and mortality associated with diabetes. Although there is substantial evidence linking diabetes with cardiovascular disease, the specific effect of hyper- (or hypo-) glycaemia is less well understood. The present review focuses on the impact that glycaemic dysregulation has on respiratory function and ROS (reactive oxygen species) generation in the endothelial cells that are critical in preventing several key steps in the atherothrombotic process. Endothelial cells are particularly susceptible to ROS-mediated dysfunction not only because of reduced cell viability and increased senescence, but also because one of the major endothelium-derived factors that help to protect against atherosclerosis, nitric oxide, is rapidly deactivated by superoxide radicals.

Glucose monitoring

Blood glucose concentrations are measured in diabetes to detect hyper- and hypo-glycaemia. Health care professionals need this information to diagnose diabetes, or states of impaired glucose tolerance, to adjust therapy and correct hyper- and hypo-glycaemia in established diabetes, to interpret signs and symptoms in patients (e.g. is confusion due to hypoglycaemia or another cause?), and to assess the risk of tissue complications developing in the future (the severity and duration of hyperglycaemia is clearly related to microvascular disease). The patient with diabetes measures blood glucose concentrations to take corrective action with food and insulin, to maintain good control, to check the safety of everyday activities (e.g. not driving when hypoglycaemic), to assess the impact of events and lifestyle and on control (exercise, diet, illness, psychological stress), and to ensure a good quality of life and the ‘peace of mind’ that knowledge of the blood glucose concentration gives. Glucose monitoring has traditionally been performed by intermittent sampling of blood glucose concentrations, either in hospital or by the patient testing their own blood glucose concentrations at home using finger-prick capillary blood samples applied to reagent strips and inserted into portable glucose meters – self-monitoring of blood glucose (SMBG). In addition, in the last decade or so, continuous glucose monitoring (CGM) has entered clinical practice as a supplement to SMBG, albeit with limited uptake at present. CGM is based on the implantation of needle-type glucose sensors, or microdialysis probes, into the subcutaneous tissue for measurement of interstitial glucose concentrations.

The experimental reproduction of enterotoxaemia in piglets

1. Whole cultures of Clostridium welchii, Type C (organisms plus toxin), produced enterotoxaemia and death when fed to new-born piglets.2. The disease could rarely be produced by suspensions of washed organisms given in the same way but was readily initiated by feeding bacteria-free toxin from Type C cultures.3. Piglets dying from enterotoxaemia induced by bacteria-free toxin showed all the extensive pathological changes of the natural disease; their intestines contained Type C organisms and far greater quantities of toxin than had been given by mouth.4. Type C organisms could not be demonstrated in the intestines of piglets from healthy litters of the same age, although such animals were carriers of the Type A strain.5. The clinical signs, with particular reference to the development of hypo-glycaemia, and the pathology of both natural and experimentally induced cases of enterotoxaemia are described.6. In the light of these findings the pathogenesis and epidemiology of enterotoxaemia in the piglet are discussed.We wish to thank Mrs B. L. Wardale and Mr P. J. D. V. Brett for general assistance. This study was aided financially by a general grant to one of us (R.F.W.G.) from the Agricultural Research Council.

The Prognosis in Schizophrenia

A search was made for statistical studies of the remission rate in cases of schizophrenia which had received no specialized treatment such as hypo-glycæmia. The search was confined to the period since 1918, as the period influenced by broader and more hopeful views of the nature and prognosis of “dementia præcox”. It was also confined to studies in which the remitted cases had been followed up for some time after discharge to avoid errors due to early relapses. The results of all these statistical follow-upstudies aie given in Table I. The various writers have classed their results in somewhat different ways, and it has been necessary, in constructing the Table, to fit all the results under standard headings.