Fundamentals about onset and progressive disease character of type 2 diabetes mellitus

ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.     

A persisting secular trend for body measurements in Dutch children. The Oosterwolde 11 study

To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.     

A retrospective study to determine the risk of red cell alloimmunization and transfusion during pregnancy

A retrospective review of post-delivery antibody records was performed at a teaching hospital and a community hospital to determine the frequency of new red cell alloantibody production and transfusion during pregnancy. If alloantibody was undetected at delivery, it was assumed that alloimmunization had not occurred. When antibody was detected, a chart review was performed to determine if the antibody was present at the beginning of the pregnancy or was newly produced during the pregnancy. A total of 17,568 pregnancies were reviewed. Antibody was detected at delivery in 948 (5.4%) cases, of which 89.5 percent (848/948) involved passive anti-D or clinically insignificant antibodies. The remaining 100 pregnancies involved clinically significant IgG antibodies. In 58 pregnancies, the antibody was detected in the first trimester, and in 42, new antibody production occurred during the pregnancy. Thus, the prevalence of new antibody production during pregnancy was 0.24 percent (95% confidence interval [CI], 0.17-0.32). Transfusion records indicated that the prevalence of transfusions during pregnancy was 0.09 percent (95% CI, 0.04-0.14). None of the women with new alloantibody formation during their pregnancies required transfusion; hence, new alloantibody production and the need for transfusion appear to be independent events. The probability of these events occurring together was 2.1 × 10(-6), or 1 in 500,000 deliveries.     

In vitro performance of the novel coronary sinus AutoRetroPerfusion Cannula

Myocardial salvage through coronary sinus intervention has been documented. The AutoRetroPerfusion Cannula is a novel device that is able to perfuse the coronary bed retrogradely through the coronary sinus with arterial blood generated from a peripheral artery with no need for a pump. The cannula consists of a distal end that, once secured in the coronary sinus, opens an umbrella-like membrane to create pressure in the coronary sinus, and at the same time has small channels directed backwards to the right atrium to provide pressure relief. The cannula is introduced from the axillary vein under local anesthesia and the proximal end, which consists of a graft, is anastomosed to the axillary artery to start autoperfusion once the distal end is secured in the coronary sinus and the occluding membrane is open. The AutoRetroPerfusion Cannula was tested in the in vitro mock loop under 50-120 mm Hg of proximal pressure and 50, 100, and 150 ml/min of total flow in the cannula. We were able to achieve the nominal design point of 40-80 mm Hg of distal pressure and 50-150 ml/min of distal flow by adjusting the number, diameter, and length of the small backwards channels.