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Production of lactulose from lactose was performed in subcritical aqueous ethanol. The effects of ethanol concentration (0-60% (w/w)) and temperature (160-220C) on the isomerization of lactose were studied. The maximum yield of lactulose (34%) was obtained from the treatment of lactose in 60% (w/w) aqueous ethanol at 200C. The isomerization and hydrolytic reactions of lactose were promoted and suppressed, respectively, by increasing ethanol concentration. The use of higher concentrations of ethanol was restricted due to the low solubility of lactose. Additionally, different feed concentrations (0.5-2.5% w/w) were studied. The maximum lactulose productivity of 63 kg/(h m3-reactor) was obtained from the treatment employing a 2.5% (w/w) feed concentration, indicating that subcritical aqueous ethanol is promising for the production of lactulose. Practical Applications Lactulose is a synthetic disaccharide comprising galactose and fructose. It has been broadly used as prebiotic food additives and drugs against constipation, hepatic encephalopathy and anti-endotoxin effects. Industrial production of lactulose is currently performed by alkaline isomerization of lactose which has several drawbacks such as high level of by-products and high cost of downstream processing. Subcritical aqueous ethanol is a novel technique for lactulose production. It can be used to overcome the disadvantages of chemical methods. The simplicity, high productivity, cost-effectiveness and environmental benignity make this technique applicable to large-scale lactulose production. [ABSTRACT FROM AUTHOR]

Isomerizations of d-glucose, d-mannose, d-fructose, d-galactose, d-xylose, d-ribose, cellobiose, maltose, lactose, and melibiose were investigated in subcritical aqueous acetonitrile. d-Glucose and d-mannose were preferred to be isomerized to d-fructose, while d-fructose mainly underwent decomposition rather than isomerization. Effects of acetonitrile concentration and temperature on saccharide isomerization were investigated using glucose as a substrate. The conversion of d-glucose and yield of d-fructose were improved with increasing acetonitrile concentration at 180 to 200 °C. In attempts to produce rare ketoses simply, d-tagatose, d-xylulose, d-ribulose, cellobiulose, maltulose, lactulose, and melibiulose were successfully produced in high yields and selectivities by treating their corresponding aldoses with subcritical aqueous acetonitrile. [ABSTRACT FROM AUTHOR]

Objective: To summarize the clinical data in preventing HBV recurrence after liver transplantation and explore a optimal individual protocol in prophylaxis of HBV recurrence., Methods: We retrospected outcomes in 195 recipients who underwent a liver transplantation for HBV-related liver disease between June 2004 and July 2008. According to the anti-virus protocol these recipients are divided into two groups as following: group A received a protocol of combination treatment of lamivudine with HBIG, and group B with combination treatment of adefovir with HBIG. With mean follow-up of 23.7 months, HBV recurrent rate was observed in overall and each group separately., Results: A total of 195 liver transplant recipients were identified that met the study criteria. At the sixth and eleventh month after operation, HBV recurrence appeared in 2 recipients, each in two groups, which were due to LAM cessation and HBV mutation respectively. Recurrent rate was 0.6% in group A, 3.7% in group B and 1% in total. There was no significant difference in HBV recurrent rate between group A and B., Conclusion: Lamivudine combined with HBIg should be considered as a reliable method in preventing HBV recurrence after liver transplantation. Better outcomes can be achieved by individual anti-virus protocol and HBIg administration according to HBV status in recipient.

Cholesterol 7-alpha-hydroxylase (CYP7A1) catalyzes a rate-limiting step in bile acid synthesis in liver, and its gene transcription is under complex regulation by multiple nuclear receptors in response to bile acids, cholesterol derivatives, and hormones. The liver receptor homolog-1 (LRH-1), a member of the fushi tarazu factor 1 subfamily of nuclear receptors, has emerged as an essential regulator for the expression of cyp7a1. In this report, we demonstrate Prox1, a prospero-related homeobox transcription factor, identified through a yeast two-hybrid screening, can directly interact with human LRH-1 (hLRH-1) and suppresses hLRH-1-mediated transcriptional activation of human cyp7a1 gene. Biochemical analysis demonstrates that Prox1 interacts with both the ligand binding domain (LBD) and the DNA binding domain (DBD) of hLRH-1. An LRKLL motif in Prox1 is important for the interaction with the LBD but not the DBD of hLRH-1. In hLRH-1 LBD, helices 2 and 10 are essential for Prox1 recruitment. The suppression by Prox1 on the transcriptional activity of hLRH-1 can be mediated through its interaction with the LBD or the DBD of hLRH-1. Gel shift assays reveal that Prox1 impairs the binding of hLRH-1 to the promoter of human cyp7a1 gene.