Incidence, risk factors and clinical outcomes of multidrug-resistant microorganism infections among patients admitted for decompensated cirrhosis: a prospective study

BACKGROUND

Bacterial infections remain one of the main complications in cirrhosis and worsen patients' prognosis and quality of life. An increase in multidrug resistant microorganism (MDRM) infections among patients with cirrhosis, together with infection-related mortality rates, have been reported in recent years. Therefore, adaptation of the initial empiric antibiotic approach to different factors, particularly the local epidemiology of MDRM infections, has been recommended. We aim to describe the main features, outcomes and risk factors of MDRM infections in patients with cirrhosis.

METHODS

Prospective registry of all episodes of in-hospital infections occurring among cirrhotic patients admitted within a 2-year period at a single center. Clinical and microbiological data were collected at the time of infection diagnosis, and the in-hospital mortality rate of the infectious episode was registered.

RESULTS

A total of 139 infectious episodes were included. The disease-causing microorganism was identified in 90 episodes (65%), of which 31 (22%) were caused by MDRM. The only two factors independently associated with MDRM infections were rectal colonization by MDRM and a nosocomial or healthcare-associated source. The infection-related mortality rate was 18.7%. MDRM infection and a past history of hepatic encephalopathy were independently associated with in-hospital mortality.

CONCLUSIONS

Almost one fourth of bacterial infections occurring in admitted cirrhotic patients were due to MDRM. Rectal colonization was the most important risk factor for MDRM infections in decompensated cirrhosis. Screening for MDRM rectal colonization in patients admitted for decompensated cirrhosis should be assessed as a tool to improve local empiric antibiotic strategies.

Enzymatic Cleavage of Glycosidic Bonds: Strategies on How to Set Up and Control a QM/MM Metadynamics Simulation

Carbohydrates play crucial roles in many biological processes, from cell-cell adhesion to chemical signaling. Their complexity and diversity, related to α/β anomeric configuration, ring substituents, and conformational variations, require a diverse set of enzymes for their processing. Among them, glycoside hydrolases (GHs) are responsible for the hydrolysis of one of the strongest bonds in nature: the glycosidic bond. These highly specialized biological catalysts select particular conformations their carbohydrate substrates to enhance catalysis. The evolution of this conformation during the reaction of glycosidic bond cleavage, known as the conformational catalytic itinerary, is of fundamental interest in glycobiology, with impact on inhibitor and drug design. Here we review some of the aspects and the main strategies one needs to take into account when simulating a reaction in a GH enzyme using QM/MM metadynamics. Several specific aspects are highlighted, from the importance of the distortion of the substrate at the Michaelis complex to the variable control during the metadynamics simulation or the analysis of the reaction mechanism and conformational itinerary. The increasing speed of computer power and methodological advances have added a vital tool to the study of GH mechanisms, as shown here and recent reviews. It is hoped that this chapter will serve as a first guide for those attempting to perform a metadynamics simulation of these relevant and fascinating enzymes.

Grape-seed procyanidins modulate inflammation on human differentiated adipocytes in vitro

Flavonoids are functional constituents of many fruits and vegetables. Procyanidins are flavonoids with an oligomeric structure, and it has been shown that they can improve the pathological oxidative state of a diabetic situation. To evaluate whether procyanidins can modulate inflammation, an event strongly associated with obesity, diabetes and insulin resistance states, we used human adipocytes (SGBS) and macrophage-like (THP-1) cell lines and administered an extract of grape-seed procyanidins (GSPE). THP-1 and SGBS cells pre-treated with GSPE showed a reduction of IL-6 and MCP-1 expression after an inflammatory stimulus. GSPE stimuli alone modulate adipokine (APM1 and LEP) and cytokine (IL-6 and MCP-1) gene expression. GSPE partially inhibited NF-kappaB translocation to the nucleus in both cell lines. These preliminary findings demonstrate that GSPE reduces the expression of IL-6 and MCP-1 and enhances the production of the anti-inflammatory adipokine adiponectin suggesting that may have a beneficial effect on low-grade inflammatory diseases such obesity and type 2 diabetes.

Nonalcoholic components in wine reduce low density lipoprotein cholesterol in normocholesterolemic rats

Using an experimental model that enables the effects of alcohol to be distinguished from the effects of the nonalcoholic components present in wine, we determined whether wine has effects other than those of alcohol on the metabolism of cholesterol. Male rats were fed a standard diet and had free access to water and either wine or an equivalent alcohol solution for 45 d or 6 mon. Alcohol intake was similar in the two groups of animals. Consumption of the alcohol solution or wine did not influence plasma cholesterol or high density lipoprotein-cholesterol. At 45 d, the consumption both of wine and of alcohol solution reduced low density lipoprotein (LDL)-cholesterol and very low density lipoprotein cholesterol. At 6 mon, only the rats that consumed wine had reduced LDL-cholesterol. After 45 d of consuming alcohol solution, total cholesterol in the aorta was significantly increased mainly as a result of the rise in free cholesterol. In the aorta, the effect of wine consumption was similar to the effect of alcohol solution consumption, although it was less intense. The only clear effect that could be ascribed to the nonalcoholic components in wine was that the LDL-cholesterol was reduced in the long term, although aortic cholesterol was not.