Heterogeneity of weight loss after gastric bypass,sleeve gastrectomy,and adjustable gastric banding

Background

Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.

Effect of estrogens on bone marrow adipogenesis and Sirt1 in aging C57BL/6J mice

Age-related bone loss has been associated with high levels of marrow adipogenesis. Estrogens (E₂) are known to regulate the differentiation of marrow precursors into osteoblasts, however, their role in bone marrow adipogenesis remain unknown. E₂ regulate adipocyte differentiation in subcutaneous and visceral fat through interaction with other nuclear receptors. This interaction has not been assessed in bone marrow adipocytes in vivo. In this study, we compared two groups of animals, young and old, after either oophorectomy (OVX) or oophorectomy plus E₂ (OVX + E₂) replacement. We found that absence of E₂ was associated with higher levels of PPARγ and lower levels of Sirt1 most significantly in the old group. In addition, old mice responded better to E₂ replacement in terms of reducing adipogenesis and PPARγ expression as well as increasing levels of Sirt1 expression. Our findings represent a new understanding of the role of E₂ in age-related bone loss, which could be mediated through the regulation of Sirt1 expression within the bone marrow. In addition, this evidence suggests that old individuals may show a better response to E₂ administration in terms of reverting the high levels of marrow fat seen in age-related bone loss.     

In vitro metabolism and toxicity assessment of toxin T-514 (Peroxisomicine A1) of Karwinskia humboldtiana in microsomes and primary cultured hepatocytes.

T-514 (Peroxisomicine A(1)) from Karwinskia humboldtiana is a dimeric hydroxyanthracenone with a highly selective cytotoxic effect on tumor cells. We evaluated the metabolism of this compound in two in vitro systems (liver microsomes and hepatocytes) and assessed the cytotoxicity of its metabolites on normal and tumor cells. Microsomes (12.5, 125 and 250 microg of protein/ml) and hepatocytes (1 x 10(6) cells/ml) were incubated with the toxin (25 microM) for 0.5, 1, 3, 6, 9, 12 and 24 h and the samples were examined using chromatographic analysis and UV spectra. Two metabolites (M1 and M2) were detected in the rat microsomes and one (M1) in the monkey microsomes. The retention times and UV spectra of the peaks were very similar to those of the toxin T-514. M1 was isolated and identified as a mixture of two isomers. The cytotoxicity of the metabolites was evaluated in Chang liver and Hep G2 cells but they did not show the selective cytotoxic effect on tumor cells seen in the original compound.     

Hepatic encephalopathy secondary to porto-systemic shunt satisfactorily treated with interventionist radiology

Hepatic encephalopathy is a reversible state of altered cognition that may occur in patients with acute or chronic liver disease or porto-systemic shunt, and in which known neurological or psychiatric signs may develop. Nitrogenated substances from intestinal digestion reach the brain without being cleared by their passage through the liver due to the presence of porto-systemic shunt. We report two cases of patients with porto-systemic shunt diagnosed with recurrent chronic hepatic encephalopathy refractory to conventional medical treatment. They were satisfactorily treated with shunt embolization using interventionist radiology techniques.     

Glucose microsensor based on electrochemical deposition of iridium and glucose oxidase onto carbon fiber electrodes1

Miniaturized glucose biosensors, prepared by electrochemical deposition of iridium and glucose oxidase (GOx), are characterized. The iridium network offers good retention of GOx and efficient preferential electrocatalytic detection of the liberated hydrogen peroxide at potentials lower than those of common interfering substances (the ascorbic acid signal actually shifts to a higher potential). The remarkable selectivity thus achieved towards the detection of glucose is coupled to a very fast response. Unlike analogous preparations of noble metal carbon fiber biosensors, a two-step electrodeposition process is required for the fabrication of Ir/GOx microelectrodes. The dependence of the biosensor response upon electrodeposition parameters, such as amounts of GOx and iridium or plating time is examined and optimized. Scanning electron microscopy is used to characterized the growth patterns of the iridium and Ir/GOx layers. The high selectivity associated with electrodeposited iridium matrices makes them very attractive for localizing other hydrogen-peroxide-liberating oxidases.     

Interleukin-1 in alcoholic cirrhosis of the liver: the influence of nutrition.

Interleukin-1 (IL-1) is a cytokine produced by the macrophage-monocyte system that has important effects on immunological responses and inflammatory reactions. Several clinical studies have shown that severe protein energy malnutrition adversely effects cell-mediated immune responses and the functional state of macrophages. The objective of this study was to analyse IL-1 production by adherent cells stimulated in vitro with lipopolysaccharide B (LPS) from patients with alcoholic cirrhosis of the liver and its possible relationship with nutritional states. Forty-five patients with alcoholic cirrhosis and 28 healthy donors were investigated. A combined index of nine anthropometric and biochemical parameters was used to evaluate nutritional status of cirrhotic patients, allowing a distinction to be made between those patients with acceptable nutrition (group I: 40%), those with slight malnutrition (group II: 37.7%), and those with severe malnutrition (group III: 22.3%). IL-1 activity was significantly lower in the cirrhosis patients than in the controls (P less than 0.001). This activity also was significantly lower in samples obtained from cirrhotics with severe malnutrition than in those with acceptable nutrition (P less than 0.05); the combined index and the sole anthropometric index gave the same results, suggesting that malnutrition may play a role in the immunoregulatory disturbances in the pathogenesis of alcoholic liver disease.