Integrated Bioinformatics Analysis for the Identification of Key Molecules and Pathways in the Hippocampus of Rats After Traumatic Brain Injury

Neurochemical Research - High-throughput and bioinformatics technology have been broadly applied to demonstrate the key molecules involved in traumatic brain injury (TBI), while no study has...     

circRNA-14723 promotes hepatocytes proliferation in rat liver regeneration by sponging rno-miR-16-5p

Circular RNA (circRNA) is a subclass of noncoding RNA (ncRNA) detected within mammalian tissues and cells. However, its regulatory role during the proliferation phase of rat liver regeneration (LR) remains unreported. This study was designed to explore their regulatory mechanisms in cell proliferation of LR. The circRNA expression profile was detected by high-throughput sequencing. It was indicated that 260 circRNAs were differentially expressed during the proliferation phase of rat LR. Among them, circ-14723 displayed a significantly differential expression. We further explored its regulatory mechanism in rat hepatocytes (BRL-3A cells). First, EdU, flow cytometry and western blot (WB) indicated that knocking down circ-14723 inhibited BRL-3A cells proliferation. Second, RNA-Pulldown and dual-luciferase report assay showed that circ-14723 could sponge rno-miR-16-5p. At last, WB showed that the reported target genes of rno-miR-16-5p, CCND1, and CCNE1 were downregulated after knocking down circ-14723. In conclusion, we found that circ-14723 exerted a critical role in G1/S arrest to promote cell proliferation via rno-miR-16-5p/CCND1 and CCNE1 axis in rat LR. This finding further revealed the regulatory mechanisms of circRNA on cell proliferation of LR, and might provide a potential target for clinical problems.     

The Helicobacter pylori Protein CagM is Located in the Transmembrane Channel That is Required for CagA Translocation

Helicobacter pylori (H. pylori) is a human gastric pathogen that colonizes the stomach in more than 50 % of the world’s human population. Infection with this bacterium can induce several gastric diseases ranging from gastritis to peptic ulcer and gastric cancer. Virulent H. pylori isolates harboring the cag pathogenicity island (cag PAI), which encodes a Type IV Secretion System (T4SS), form a pilus for the injection of its major virulence protein CagA into gastric cells. Several cag PAI genes have been identified as homologues of T4SS genes from Agrobacterium tumefaciens, while the other members in cag PAI still have no known function. We studied one of such proteins with unknown function, CagM, which was predicted to have a putative N-terminal signal sequence and at least three transmembrane helices. To determine the subcellular localization of CagM, we performed a cell fractionation procedure and produced rabbit anti-CagM polyclonal antibodies for immunoblotting assays. Furthermore, we generated an isogenic ΔcagM mutant to investigate the ability of CagA translocation compared with the wild-type NCTC 11637 strain using GES-1 and MKN-45 cell infection experiments. Our results indicated that CagM was mainly located in the bacterial membrane, partially located in the periplasm, and essential for CagA translocation both in GES-1 and MKN-45 cells, which suggested that CagM was one of the core members of Cag T4SS and localized in the transmembrane channel.     

Association between -251A>T polymorphism in the interleukin-8 gene and oral cancer risk: A meta-analysis

Background

Emerging evidence showed that the most common functional polymorphism (-251A>T, rs4073) in the promoter region of the interleukin-8 (IL-8) gene is involved in the regulation of the activities of interleukin-8, thus increasing an individual's susceptibility to oral cancer; but individually published results are inconclusive. The aim of this meta-analysis was to investigate the associations between IL-8 -251A>T polymorphism and oral cancer risk.

Methods

The PubMed, Embase, Web of Science and CBM databases were searched for all articles published up to October 1st, 2012 that addressed IL-8 -251A>T polymorphism and oral cancer risk. Statistical analyses were performed using STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

Six case–control studies were included with a total of 1324 oral cancer cases and 1879 healthy controls. When all available studies were pooled into the meta-analysis, the results showed that the AA and AT genotypes of IL-8 -251A>T polymorphism were associated with increased risk of oral cancer (OR = 1.23, 95% CI: 1.03–1.46, P = 0.025; OR = 1.25, 95% CI: 1.07–1.47, P = 0.006; respectively). In the subgroup analysis by ethnicity, significant associations were observed between the AA and AT genotypes of IL-8 -251A>T polymorphism and increased risk of oral cancer among Caucasian populations (OR = 1.40, 95% CI: 1.14–1.72, P = 0.001; OR = 1.29, 95% CI: 1.06–1.57, P = 0.011; respectively). However, no statistically significant associations were found between IL-8 -251A>T polymorphism and oral cancer risk among Asian populations.

Conclusions

Results from the current meta-analysis indicate that the AA and AT genotypes of IL-8 -251A>T polymorphism might increase the risk of oral cancer, especially among Caucasian populations.     

An extraction free modified o-phthalaldehyde assay for quantifying residual protein and microbial biofilms on surfaces

Abstract

Biological contamination of surfaces in industry and healthcare is an important vector of disease transmission. Current assays for detecting surface-adherent contamination require extraction of biological soil. However, physical inaccessibility or poor solubility may limit recovery. Here, how the o-phthalaldehyde (OPA) protein assay can be modified to measure residual protein (modeled with bovine serum albumin) or biofilm on a surface without extraction is described. The assay limit of detection (LOD) for protein was 1.6 µg cm^?2. The detection threshold for Staphylococcus epidermis biofilm was 117 µg cm^?2. The clinical utility of the method was demonstrated for measurements taken from clinically used endoscopes. Since this method is more sensitive than extraction-based testing, clinical results should not be compared with conventional benchmarks. By enabling direct detection and quantification of soils in complex or hard-to-reach areas, this method has potential to improve the margin of safety in medical and industrial cleaning processes.