Hydroxyethyl starch (HES) is one of the most frequently used plasma substitutes. A variety of different HES solutions exist worldwide, which differ greatly in their pharmacological properties. HES is classified according to its manufactured or in vitro molecular weight (MW) into high MW (450-480 kDa), medium MW (200 kDa), and low MW (70 kDa) starch preparations. However, this is not sufficient, because as HES is metabolized in vivo, its MW changes, and it is the in vivo MW which is responsible for the therapeutic and adverse effects of each HES. The rate of metabolization depends mainly on the degree of hydroxyethyl substitution (ranging from 0.4 to 0.7), and the C2/C6 ratio of hydroxyethylation. A high degree of substitution and a high C2/C6 ratio lead to a slow metabolization of HES, resulting in a large in vivo MW. Slowly degradable high MW HES 450/0.7 and medium MW HES 200/0.62 have a high in vivo MW and are eliminated slowly via the kidneys. As a result, these starches have a relatively long-lasting volume effect. When infusing higher volumes (>1500 ml) are infused, large molecules accumulate in the plasma. This can result in bleeding complications due to decreased factor VIII/von Willebrand factor, platelet function defects, incorporation into fibrin clots, and an unfavorable effect on rheological parameters. Rapidly degradable medium MW HES 200/0.5 or low MW HES 70/0.5 are quickly split in vivo into smaller, more favorable molecule sizes, resulting in faster renal elimination, shorter volume effect, and fewer adverse effects on coagulation and rheological parameters. For historical and marketing reasons, only slowly degradable, high MW HES (480/0.7) is available in the United States. In Europe, a large variety of HES solutions are available, dominated by medium MW, easily degradable HES (200/0.5). Because of increasing international competition and the availability of newly developed starches, it is important to be aware of the pharmacological properties of HES and the advantages and disadvantages of the individual preparations.

To investigate the expression of the endocannabinoid 1 and 2 receptors by human adipocyte cells of omental and subcutaneous fat tissue, as well as to determine whether these receptors are functional. The expression of CB1 and CB2 receptors on human adipocytes was analyzed by western blotting, immunohistology and immunocytology. We also investigated intracytoplasmic cyclic AMP level modulation following CB1 and CB2 receptor stimulation by an enzymatic immuno assay. All mature adipocytes, from visceral (epiploon) and subcutaneous fat tissue, express CB1 and CB2 on their plasma membranes. We also demonstrate in this study that adipocyte precursors (pre-adipocytes) express CB1 and CB2 on their plasma membranes and that both receptors are functional. Activation of CB1 increases intracytoplasmic cyclic AMP whilst CB2 activation leads to a cyclic AMP decrease. Here we demonstrate, for the first time, that adipocytes of human adipose tissue (mature adipocytes and pre-adipocytes) express functional plasma membrane CB1 and CB2 receptors. Their physiological role on the adipose tissue is not known. However, their major involvement in the physiology of other tissues leads us to suppose that they could play a significant role in the homeostasis of the energy balance and/or in the regulation of adipose tissue inflammation.

The presence of definite clinical evidence of coronary artery disease and older age were the most important preoperative predictors of an adverse cardiac outcome after abdominal aortic surgery. These results suggest that the routine use of dipyridamole-thallium SPECT and radionuclide angiography for screening before abdominal aortic surgery may not be justified.

Administration of DCLHb allowed a significant number (19%) of cardiac surgery patients to avoid exposure to erythrocytes postoperatively.