Expression and clinical significance of circulating miR-103a-2 in serum from patients with nonalcoholic fatty liver disease / 临床检验杂志

Objective To investigate the significance of miR-103 as noninvasive biomarker for diagnosis of nonalcoholic fatty liver disease (NAFLD).Methods The serum samples were collected from healthy subjects and NALFD patients to detect biochemical parameters.NucleoZOL method was used to isolate serum miRNA.SYBR Green qPCR was used for relatively quantitative analysis of miR103a-2.The correlations between miR-103a-2 and biochemical parameters were analyzed by Spearman method.Results Compared with healthy control group,the levels of total cholesterol (TC),triacylglyceride (TG),alanine aminotransferase (ALT) and glutamyl transpeptidase (γ-GGT) were all significantly increased in NAFLD group (P ＜ 0.01).Compared with the NAFLD group accompanying ortholiposis,the levels of TC,TG and low density lipoprotein-cholesterol (LDL-C) were all significantly increased in the NAFLD group accompanying dyslipidemia (P ＜0.01).Compared with the healthy control group,the level of serum miR-103a-2 increased in both NAFLD with ortholiposis group (P ＜ 0.05) and NAFLD with dyslipidemia group (P ＜ 0.01).The level of serum miR-103a-2 was positively correlated with serum TC (r =0.495,P =0.001).Conclusion Serum miR-103a-2 may be a more sensitive parameter for noninvasive screening of NAFLD than the parameters of blood lipid.

STUDIES ON XYLANASE PRODUCTION BY ASPERGILLUS CLAVATUS 22 / 微生物学通报

A high xylanase producing strain 22 of Aspergillus clavatus was screened from 105 strains of molds and yeasts. The suitable medium consisted of (g/L): bagasse hemicellulose 30, NH_4NO_3 5, yeast extract 5, wheat bran 10, Tween 80 1 and a small quantity of other minerals; initial pH 5.5. Theoptimalsporeinoculumwas4.9X10~6spores/ml (final concentration). Theactivity of xylanase was as high as 335.9 U/ml in shake-flask experiment at 28℃ for 72 h. The optimal temperature and pH for xylanase reaction were 50℃ and pH 4.8. 72.6% of its original activity was remained after incubation at 50℃ for 1 h, and 90% of the enzym activity was observed upon storage at 8℃ for 9 days . Sugars. Na~+. Ca~(2+). and Zn~(2+) increased its activity wherease Co~(2+)and Cu~(2+) inhibited it.