Salivary microbial communities associated with severe early childhood caries / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To compare the salivary microbial profiles of healthy subjects and those with severe early childhood caries (S-ECC) by using high-throughput sequencing.</p><p><b>METHODS</b>Salivary samples were obtained from children with S-ECC (group C, n=24) and healthy children (group H, n=24). Total metagenomic DNA was extracted, and DNA amplicons of the V1-V3 hypervariable region of the 16S rRNA gene were generated and subjected to 454 sequencing. The characteristics of oral microbial communities from the two groups were compared based on microbial diversity and taxonomy assignment.</p><p><b>RESULTS</b>First, the microbial richness was significantly higher in group C than group H (P<0.05). Second, the microbial community structure was significantly different for the groups H and C (P<0.01). In addition, caries microbiota was significantly conserved in group C (P<0.001). High expression of suspected cariogenic microorganisms in group C (P<0.1) and health related microorganisms in group H (P<0.1) were identified. Finally, models of caries risk assessment were proposed to distinguish caries from healthy subjects with over 70% accuracy.</p><p><b>CONCLUSIONS</b>Salivary microbiota and certain taxa, such as caries-associated taxa (Prevotella), may be useful to screen/assess the children's risk of developing caries.</p>

Effects of RhoA gene silencing by RNA interference on invasion of tongue carcinoma / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the effects of RhoA down-regulation by RNA interference on the invasion of tongue carcinoma Tca8113 and SCC-4.</p><p><b>METHODS</b>Determination of the human RhoA sequence as well as the design and constructionof a short specific small interfering RNAs (siRNA) were performed. The siRNA of RhoA gene was transfected into humantongue squamous cell carcinoma Tca8113 and SCC-4 cells line by Lipofectamine 2000. Quantitative real-time polymerasechain reaction was used to examine the mRNA expressionlevels of RhoA. Protein expressions of mRNA, galectin-3,and matrix metalloproteinase (MMP)-9 were evaluated byWestern blot. Transwell invasion assay was performed toassess the invasion ability of tongue carcinoma.</p><p><b>RESULTS</b>RhoA expressions in Tca8113 and SCC-4 cells were reducedsignificantly after transfection of RhoA-siRNA. Protein levels f galectin-3 and MVP-9 were also down-regulated significantly. Invasion ability was inhibited as well.</p><p><b>CONCLUSION</b>RhoA-siRNA can effectively inhibit RhoA expression in Tca8113 and SCC-4 cells. The invasion ability of tongue carcinoma cells decreased with down-regulation of the protein expressions of galectin-3 and MMP-9, indicating that RhoA-siRNA can inhibit invasion of tongue carcinoma. Results show that RhoA may play an important role in the processes of invasion and metastasis of tongue carcinoma.</p>

Effect of altitude chronic hypoxia on liver enzymes and its correlation with ACE/ACE2 in yak and migrated cattle / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the difference of liver enzyme levels and its correlation with serum ACE/ACE2 among yak and cattle on Qinghai-Tibetan plateau, and to further explore the biochemical mechanism of their liver of altitude adaptation.</p><p><b>METHODS</b>The serum samples of yak were collected at 3,000 m, 3,500 m, 4,000 m and 4,300 m respectively, meanwhile the serum samples of migrated cattle on plateau (2,500 m) and lowland cattle (1,300 m) were also collected. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), cholinesterase (CHE), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), serum lipase (LPS), angiotensin converting enzyme(ACE), angiotensin converting enzyme-2 (ACE2) in serum were measured by using fully automatic blood biochemcal analyzer. We analysed the differences of the above enzymes and its correlation with ACE/ACE2. We used one way analysis of variance (ANOVA).</p><p><b>RESULTS</b>The levels of ALT in 4,000 m group and 4,300 m group of yak increased significantly compared with other groups, there were no statistically significant differences in AST, CHE, GGT, ACE/ACE2 levels of yaks at different altitudes. As compared to lowland cattle, the serum levels of AST and CHE were increased, the level of LPS and ACE was decreased significantly, respectively, and especially, the ratio of ACE/ACE2 of migranted cattle reduced nearly two times. The levels of LPS were significantly correlated to the ratio of ACE/ACE2 in yak (r = 0.357, P < 0.01), and a high correlation between ALP and ACE/ACE2 in lowland cattle( r = 0.418, P < 0.05), But the biggest contribution rate of the ratio of ACE/ACE2 was only 17.5% for the changes of the levels of liver enzyme.</p><p><b>CONCLUSION</b>The results indicated that with the altitude increased did not significantly influence the changes of liver enzymes' activities in mountainous yaks but not in cattle. However, all above these changes weren't actually correlated to the ratio of ACE/ACE2.</p>