Yeast screening from avermectins wastewater and investigation on the ability of its fermentation.

Wastewater from avermectin production is refractory with high output, high chemical oxygen demand (COD) concentration and high cost further. The current wastewater treatment technology, with little reuse of the organic material, needs high dilution ratio during treatment. Yeast single cell protein was produced from the wastewater of avermectins fermentation in this research. First, the yeast strain (H-1) which show enough tolerance to avermectins residue was screened from the wastewater, and it was identified as being most closely related to Candida tropicalis (100%, EF120592.1) using 18S rDNA gene sequence analysis. Second, its growth characteristics in the avermectins wastewater were studied. The dry biomass reached the maximal point of 10 g/L, the COD removal was up to 66.67%, and avermectins removal in the wastewater was 99.48% at the optimal condition that it was liquid volume 50 ml (250 ml flask), pH 4.0, temperature 30°C, inoculum volume 10% (V/V) and fermentation period 20 h. Third, the nutritional contents of dry yeast powder were determined, in which the water content was 8.12%, ash content was 5.18% and the crude protein was 40.02%. The dry yeast powder from avermectin waste liquor was promising to be used as a raw material or nitrogen source for commercial production of avermectins. The project was economically feasible by primary cost accounting.

Endoscopic Biliary Drainage Versus Percutaneous Transhepatic Biliary Drainage in Patients with Resectable Hilar Cholangiocarcinoma: A Systematic Review and Meta-Analysis.

BACKGROUND: Hilar cholangiocarcinoma (HCCA) is a rare tumor, usually associated with obstructive jaundice and unfavorable prognosis. Obstructive jaundice can affect the liver, kidney, heart, and the immune system of the patients. Currently, controversy exists in whether preoperative biliary drainage (PBD) is of any benefit to the patients, and the best way for PBD in patients with resectable HCCA of malignant biliary obstruction remains to be determined. OBJECTIVES: To compare the clinical outcomes and effectiveness of endoscopic biliary drainage (EBD) treatment with those of percutaneous transhepatic biliary drainage (PTBD) treatment in patients with malignant biliary obstruction caused by resectable HCCA. MATERIALS AND METHODS: The databases including MEDLINE, EMBASE, PubMed, CBM (China Biological Medicine Database), and CNKI were employed to identify the clinic trials on EBD versus PTBD for malignant biliary obstruction associated with resectable HCCA from January 2008 to October 2017. A systematic review and meta-analysis were carried out. RESULTS: Six trials were identified and included in this study. Overall, the differences in technical success rate, R0 resection, incidence of total complication after resection, postoperative hospitalization time, resection time, and recurrence were not statistically significant between the EBD group and PTBD group (all P > .05). However, the incidence of total complications after EBD treatment is higher than that after PTBD treatment (P < .05). CONCLUSION: For patients with obstructive jaundice associated with HCCA, current evidence indicate no superiority of PTBD over EBD regarding clinical feasibility and success rate, but data suggest a better clinical safety of PTBD compared with EBD in short-term postoperation. In long-term evaluation, the differences in clinical outcomes are not statistically significant between PTBD and EBD.

Laparoscopic versus endoscopic management of choledocholithiasis in patients undergoing laparoscopic cholecystectomy: a meta-analysis.

AIM: To compare the clinical effectiveness of the treatment of choledocholithiasis by laparoscopic common bile duct (CBD) exploration and by endoscopic sphincterotomy (EST). MATERIALS AND METHODS: A meta-analysis of studies about CBD stones was performed to analyze EST in comparison with laparoscopic CBD exploration procedures. Trials were identified by searching the Medline, EMBASE, PubMed, CBM, and CNKI databases from January 1990 to December 2012 for laparoscopic CBD exploration or EST for CBD stones. RESULTS: Fifteen studies were identified in the meta-analysis. The incidence of bleeding or pancreatitis in the EST group was higher than that in the laparoscopic group. However, the incidence of bile leakage in the EST group was lower than that in the laparoscopic group. The differences in cases of retained stones or total complications were not statistically significant between the laparoscopic and EST groups (P>.05). There were more successful cases in the laparoscopic group than in the EST group (P<.05). Hospital cost was less in the laparoscopic group than in the EST group (P<.05). Mean operation time and hospital stay in the laparoscopic group were shorter than those in the EST group (P<.05). CONCLUSIONS: To some degree, laparoscopic treatment of the CBD may be a better way of removing stones than EST.

Radiofrequency ablation in the treatment of small hepatocellular carcinoma: a meta analysis.

AIM: To evaluate survival and recurrence after radiofrequency ablation (RFA) for the treatment of small hepatocellular carcinoma (HCC) using a meta-analysis. METHODS: Literature on RFA vs surgical resection for the treatment of small HCC published between January 1990 and December 2008 was retrieved. A meta-analysis was conducted to estimate pooled survival and recurrence ratios. A fixed or random effect model was established to collect the data. RESULTS: The differences in overall survival at 1-year, 3-years and at end of follow-up were not statistically significant between the RFA and surgery groups (P > 0.05). There were no differences in 1-year and 3-year recurrences between the RFA and surgery groups (P > 0.05). However, recurrence in the RFA group was lower than that in the surgery group up to the end of follow-up (P = 0.03). Survival was not significantly different. There was a significant difference in recurrences at the end of follow-up after RFA compared with surgical resection. CONCLUSION: RFA did not decrease the number of overall recurrences, and had no effect on survival when compared with surgical resection in a selected group of patients.

Purification of nattokinase by reverse micelles extraction from fermentation broth: effect of temperature and phase volume ratio.

Nattokinase is a novel fibrinolytic enzyme that is considered to be a promising agent for thrombosis therapy. In this study, reverse micelles extraction was applied to purify and concentrate nattokinase from fermentation broth. The effects of temperature and phase volume ratio used for the forward and backward extraction on the extraction process were examined. The optimal temperature for forward and backward extraction were 25 degrees C and 35 degrees C respectively. Nattokinase became more thermosensitive during reverse micelles extraction. And it could be enriched in the stripping phase eight times during backward extraction. It was found that nattokinase could be purified by AOT reverse micelles with up to 80% activity recovery and with a purification factor of 3.9.