Taxus chinensis ameliorates diabetic nephropathy through down-regulating TGF-β1/Smad pathway / 中国天然药物

Diabetic nephropathy (DN) is one of the common microvascular complications of diabetes mellitus. Renal fibrosis is closely related to the deterioration of renal function. The present study aimed to investigate protective effect of Taxus chinensis on high-fat diet/streptozotocin-induced DN in rats and explore the underlying mechanism of action. The rat DN model was established via feeding high fat diet for 4 weeks and subsequently injecting streptozotocin (30 mg·kg body weight) intraperitoneally. The rats with blood glucose levels higher than 16.8 mmol·L were selected for experiments. The DN rats were treated with Taxus chinensis orally (0.32, 0.64, and 1.28 g·kg) once a day for 8 weeks. Taxus chinensis significantly improved the renal damage, which was indicated by the decreases in 24-h urinary albumin excretion rate, blood serum creatinine, and blood urea nitrogen. Histopathological examination confirmed the protective effect of Taxus chinensis. The thickness of glomerular basement membrane was reduced, and proliferation of mesangial cells and podocytes cells and increase in mesangial matrix were attenuated. Further experiments showed that Taxus chinensis treatment down-regulated the expression of TGF-β1 and α-SMA, inhibited phosphorylation of Smad2 and Smad3. These results demonstrated that Taxus chinensis alleviated renal injuries in DN rats, which may be associated with suppressing TGF-β1/Smad signaling pathway.

Rapid Identification and Subtyping of Enterobacter cloacae Clinical Isolates Using Peptide Mass Fingerprinting / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To establish a domestic database of Enterobacteria cloacae (E. cloacae), and improve the identification efficiency using peptide mass fingerprinting.</p><p><b>METHODS</b>Peptide mass fingerprinting was used for the identification and subtyping of E. cloacae. Eighty-seven strains, identified based on hsp60 genotyping, were used to construct and evaluate a new reference database.</p><p><b>RESULTS</b>Compared with the original reference database, the identification efficiency and accuracy of the new reference database was greatly improved at the species level. The first super reference database for E. cloacae identification was also constructed and evaluated. Based on the super reference database and the main spectra projection dendrogram, E. cloacae strains were divided into two clades.</p><p><b>CONCLUSION</b>Peptide mass fingerprinting is a powerful method to identify and subtype E. cloacae, and the use of this method will allow us to obtain more information to understand the heterogeneous organism E. cloacae.</p>

Taxus chinensis ameliorates diabetic nephropathy through down-regulating TGF-β1/Smad pathway / 中国天然药物

Diabetic nephropathy (DN) is one of the common microvascular complications of diabetes mellitus. Renal fibrosis is closely related to the deterioration of renal function. The present study aimed to investigate protective effect of Taxus chinensis on high-fat diet/streptozotocin-induced DN in rats and explore the underlying mechanism of action. The rat DN model was established via feeding high fat diet for 4 weeks and subsequently injecting streptozotocin (30 mg·kg body weight) intraperitoneally. The rats with blood glucose levels higher than 16.8 mmol·L were selected for experiments. The DN rats were treated with Taxus chinensis orally (0.32, 0.64, and 1.28 g·kg) once a day for 8 weeks. Taxus chinensis significantly improved the renal damage, which was indicated by the decreases in 24-h urinary albumin excretion rate, blood serum creatinine, and blood urea nitrogen. Histopathological examination confirmed the protective effect of Taxus chinensis. The thickness of glomerular basement membrane was reduced, and proliferation of mesangial cells and podocytes cells and increase in mesangial matrix were attenuated. Further experiments showed that Taxus chinensis treatment down-regulated the expression of TGF-β1 and α-SMA, inhibited phosphorylation of Smad2 and Smad3. These results demonstrated that Taxus chinensis alleviated renal injuries in DN rats, which may be associated with suppressing TGF-β1/Smad signaling pathway.

Pulsed-field gel electrophoresis typing on non-O157 Shiga toxin-producing Escherichia coli isolates / 中华流行病学杂志

<p><b>OBJECTIVE</b>To establish a database and to understand the molecular epidemiological features of non-O157 Shiga toxin-producing Escherichia coli (STEC) isolates from different animal reservoirs and patients.</p><p><b>METHODS</b>Pulsed-field gel electrophoresis (PFGE) was performed according to the PulseNet protocol with minor modifications. A dendrogram was constructed using the BioNumerics.</p><p><b>RESULTS</b>Under the PulseNet protocol, 62 PFGE patterns were obtained from 76 non-O157 STEC isolates and then divided into A to M groups. Isolates from different sources were widely distributed in different groups, but were predominant seen in certain groups.</p><p><b>CONCLUSION</b>The non-O157 STEC isolates in China were highly polymorphic. PulseNet protocol seemed to be suitable for the typing of Chinese non-O157 STEC isolates.</p>

Secretion expression of cholera toxin B subunit in food-grading Lactococcus lactis expression system / 中华流行病学杂志

<p><b>OBJECTIVE</b>To clone and secretion express cholera toxin B subunit (CTB) in food-grading Lactococcus lactis expression systems.</p><p><b>METHODS</b>ctB fragment that encoding CTB was amplified by polymerase chain reaction (PCR) using the genomic DNA of Vibrio cholera strain 569B as template and was inserted into two secretion expression vector pSQZ and pSQ to construct food-grading expression system L.lactis MBP71/pSQZ-ctB and L.lactis MBP71/pSQ-ctB. The expressed CTB was detected by Western-blot assay.</p><p><b>RESULTS</b>The ctB fragment was successfully amplified from Vibrio cholera strain 569B and inserted into two secretion expression vectors pSQZ and pSQ to construct food-grading expression system L. lactis MBP71/pSQZ-ctB and L. lactis MBP71/pSQ-ctB. Western-blot assay demonstrated that CTB was secretion and expressed from L.lactis MBP71 harboring vectors pSQZ-ctB and pSQ-ctB, and the quantity of CTB secreted by L. lactis MBP71/pSQ-ctB was about 2 microg/ml, higher than that of L. lactis MBP71/pSQZ-ctB.</p><p><b>CONCLUSION</b>CTB was successfully secreted and expressed by food-grading L. lactis expression systems.</p>