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Clarifying the mechanisms underlying microbial community assembly from regional microbial pools is a central issue of microbial ecology, but remains largely unexplored. Here, we investigated the gut bacterial and fungal microbiome assembly processes and potential sources in Drosophila simulans and Dicranocephalus wallichii bowringi, two wild, sympatric insect species that share a common diet of waxberry. While some convergence was observed, the diversity, composition, and network structure of the gut microbiota significantly differed between these two host species. Null model analyses revealed that stochastic processes (e.g., drift, dispersal limitation) play a principal role in determining gut microbiota from both hosts. However, the strength of each ecological process varied with the host species. Furthermore, the source-tracking analysis showed that only a minority of gut microbiota within D. simulans and D. wallichii bowringi are drawn from a regional microbial pool from waxberries, leaves, or soil. Results from function prediction implied that host species-specific gut microbiota might arise partly through host functional requirement and specific selection across host-microbiota coevolution. In conclusion, our findings uncover the importance of community assembly processes over regional microbial pools in shaping sympatric insect gut microbiome structure and function.

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Objective@#To establish a hydrogen peroxide (H2O2) induced injury model of pulmonary artery endothelial cells (PAECs) and explore the molecular mechanisms of oxidative stress on the structure and function of PAECs in this model.@*Methods@#Human PAECs were treated with H2O2 at different concentrations (25, 50, 100, 200, 400, 800, 1 600, 3 200, 6 400 μmol/L) for 4 and 24 h, respectively. The PAECs survival curve was obtained according to the cell viability measured by CCK-8 assay. The cell apoptosis of PAECs was detected by flow cytometry. The reactive oxygen species (ROS) generation and mitochondrial activity were measured using small molecule fluorescent probes. Proteins were extracted and the phosphorylation levels of signal molecules in PAECs were detected by Western blot assays.@*Results@#(1) The effect of H2O2 at various concentrations on cell viability of PAECs: cell viability of PAECs decreased in proportion to increasing concentration of H2O2 after incubation for 4 h. The half maximal inhibitory concentration (IC50) of PAECs exposed to H2O2 for 4 and 24 h were 397.00 and 488.77 μmol/L, respectively. (2) The effect of H2O2 on cell apoptosis of PAECs: After H2O2 incubation for 4 h, proportions of PAECs at late-apoptosis ((22.58±3.69) %) and necrotic stage( (11.86±4.27)%) were significantly higher than those of control PAECs at late-apoptosis stage( (3.41±1.44)%, P<0.01) and at necrotic stage ((1.94±1.15) % , P<0.05). The survival rate of PAECs post H2O2 was dramatically lower than that of control PAECs ((7.98±3.21)% vs. (48.89±8.08)%, P<0.01). However, there is no statistical difference between both groups regarding to the early apoptosis. (3) The effect of H2O2 on mitochondrial activity and ROS production of PAECs: the mitochondrial activity and ROS generation of PAECs treated by H2O2 were significantly increased compared to those in control PAECs (P<0.01). (4) The effect of H2O2 on signaling molecules in PAECs: there was a significant increase in phosphorylation level of Akt in PAECs incubated with H2O2 for 30 minutes compared to that in control PAECs (P<0.01), while there was no significant difference in levels of Akt between H2O2 treated PAECs and control PAECs. Phosphorylation level of JNK as well as p38 were also significantly upregulated in H2O2 treated PAECs (P<0.01).@*Conclusion@#H2O2 at the concentration of 400 μmol/L could induce human PAECs injuries via the regulation of Akt and MAPK signaling pathways.

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PURPOSE: The objective was to compare isocaloric high-protein (HP) test meals with normal-protein (NP) test ones on satiety and ghrelin in human being. METHODS: Systematic searches were conducted by using PubMed, Cochrane library, EMBASE, and HighWire Press to identify randomized, crossover trials that investigated the acute effects of isocalorically prescribed HP versus NP test meals on satiety and ghrelin. RESULTS: Pooled analyses showed that subjects with HP test meals had a significantly higher acute satiety area under the curve (AUC) than those with NP test meals (P < 0.001). Conversely, the former had a markedly lower level of acute ghrelin at 180 min as well as acute glucose AUC, although they had a notably higher glucose at 180 min (P = 0.008). CONCLUSIONS: The meta-analysis showed that the acute consumption of HP did produce more satiety. In addition, relative to NP test meals, HP test ones may be useful in regulating postprandial glucose, whereas a significantly higher preprandial glucose combined with a lower concentration of ghrelin may contribute to the decrease in ad libitum caloric intake.

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<p><b>BACKGROUND</b>Iron is a biocorrodible metal that might be used in bioabsorbable stents. This study investigated the effects at the cellular and protein levels of soluble divalent iron (ferrous gluconate) and soluble trivalent iron (ferric chloride) on the proliferation of human aortic smooth muscle cell (HASMC) in vitro.</p><p><b>METHODS</b>The water-soluble tetrazolium (WST-1) test was used to evaluate the effect of iron on proliferation of HASMC and Western blotting was used to measure the levels of signaling proteins involved in proliferative and apoptosis pathways.</p><p><b>RESULTS</b>HASMC proliferation was inhibited in a concentration dependent manner after treatment with soluble divalent and trivalent iron at concentrations of 100-500 µmol/L. Western blotting analysis showed that the proliferating cell nuclear antigen (PCNA) expression following treatment with soluble divalent iron and trivalent iron at 100, 300 and 500 µmol/L was reduced compared to the control. The PCNA expression decreased with increasing iron concentration and to a greater extent with the trivalent iron than with the divalent iron treatment group. The p53 expression was markedly increased in a concentration dependent manner in both iron treatment groups.</p><p><b>CONCLUSION</b>The soluble divalent iron and, to a greater degree trivalent iron, inhibited HASMC proliferation in a dosedependent manner, which may be attributed to reduction of PCNA expression and increase of p53 expression.</p>

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<p><b>BACKGROUND</b>Dicycloplatin is a relatively safe third generation platinum-complex anti-cancer drug. The present study focused on the effects of dicycloplatin on in vitro proliferation and apoptosis of human aortic smooth muscle cells (HASMC) and human aortic endothelial cells (HAEC).</p><p><b>METHODS</b>Proliferation of HASMC and HAEC, DNA content, and cellular levels of proliferation- and apoptosis-related proteins were assessed using the (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay, flow cytometry and Western blotting assays, respectively.</p><p><b>RESULTS</b>Dicycloplatin at 10 ng/ml significantly inhibited HASMC proliferation, however, 10 µg/ml were required to significantly inhibit HAEC proliferation. Cell cycle analysis showed that dicycloplatin was a non-specific inhibitor of the cell cycle. Although dicycloplatin significantly decreased proliferating cell nuclear antigen (PCNA) expression in HASMC at all concentrations tested, it did not significantly affect PCNA expression in HAEC; Bax and p53 protein expression was upregulated in dicycloplatin groups.</p><p><b>CONCLUSIONS</b>Dicycloplatin at nanogram concentrations significantly inhibits HASMC proliferation, although the effect is relatively weaker than that of sirolimus. In contrast, the effect of dicycloplatin on inhibition of HAEC proliferation is much less pronounced than that on HASMC. The latter characteristics point to the potential for use of dicycloplatin in drug-eluting stents.</p>

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AIM: To assess the degree of oxidative damage during acute myocardial infarction and reperfusion, and to clarify the protective effect of Tongxinluo in mini-swine model. METHODS: Thirty mini-swines were randomized into 5 study groups: sham group, model group, low dose (0.05 g·kg~(-1)·d~(-1)), medium dose (0.2 g·kg~(-1)·d~(-1)) and high dose (0.5 g·kg~(-1)·d~(-1)) of Tongxinluo groups (pretreated with Tongxinluo for 3 d). Animals except in sham group were subjected to 3 h of coronary occlusion followed by 1 h of reperfusion. Concentrations of total antioxidative capability (T-AOC), total superoxide dismutase (T-SOD), reduced glutathione (GSH) and malondialdehyde (MDA) in blood sample and the myocardium were measured. RESULTS: (1) T-AOC, T-SOD and GSH in serum significantly decreased (all P<0.05), while MDA significantly increased (P<0.01) at 3 h after AMI in comparison with those at baseline. Compared to those at 3 h after AMI, the contents of T-AOC, T-SOD and GSH at 1 h after reperfusion significantly decreased (all P<0.01), accompanied by increase of MDA (P<0.01). (2) Compared to those in normal area, levels of T-AOC, T-SOD and GSH in reperfusion myocardium decreased significantly (all P<0.01) and MDA increased significantly (P<0.01). T-AOC, T-SOD and GSH in no-reflow myocardium further decreased (all P<0.01) and MDA increased (P<0.01) as compared to those in reperfusion myocardium. (3) Compared to model group, medium dose of Tongxinluo increased the contents of T-AOC and T-SOD and reduced MDA production in serum at 3 h after AMI (all P<0.05), while medium dose of Tongxinluo increased T-SOD level at 1 h after reperfusion (P<0.05). High dose of Tongxinluo increased the levels of T-AOC and T-SOD and decreased MDA content in serum at 3 h after AMI and 1 h after reperfusion (all P<0.05). (4) The medium dose of Tongxinluo increased T-AOC content (P<0.05) and reduced MDA (P<0.05) in reperfusion myocardium, while high dose of Tongxinluo increased T-AOC, T-SOD and GSH (all P<0.05), reduced MDA (P<0.01) in reperfusion myocardium, and also increased T-AOC, T-SOD (all P<0.05), reduced MDA (P<0.01) in no-reflow area as compared to those in model group. CONCLUSION: Impairment of antioxidant defense system in vivo and imbalance of redox homeostasis in myocardium region might play an important role in the pathogenesis of no-reflow after myocardial acute infarction following reperfusion. Tongxinluo protects myocardium from reperfusion injury by improving antioxidant defense and attenuating oxidative damage.

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Objective To investigate the effects of adenosine preconditioning on the expression of myocardial tumor necrosis factor-alpha (TNF-α) mRNA and intercellular adhesion molecule-1 (ICAM-1) mRNA in patients undergoing off-pump coronary artery bypass graft (OPCABG).Methods Forty patients, aged 44-68 yr, with more than three coronary artery obstructions and the ejection fraction≥40%,undergoing elective OPCABG, were randomly divided into 2 groups (n=20 each): control group and adenosine group. Adenosine group received adenosine preconditioning, with the initial infusion rate of 50 μg. kg-1.min-1, then increasing to 100μg.kg-1.min-1after 1 min, finally increasing to 150 μg. kg-1 . min-1 after 2 min and maintaining for 7 min. Vascular anastomosis was started at 5 min after preconditioning. While the control group received normal saline instead of adenosine. Tissue samples of the right auricle were taken before preconditioning (baseline) and at 15 min after blood current retum to measure the expression of myocardial TNF-α mRNA and ICAM-1 mRNA. The myocardial ultrastructure was observed and hemodynamic parameters were monitored.Results The myocardial damage was milder in the adenosine group than in the control group. The expression of myocardial TNF-α mRNA and ICAM-1 mRNA was significantly lower in the adenosine group than in the control group ( P＜0.05).Conclusion Adenosine preconditioning can attenuate myocardial ischemia-reperfusion injury in patients undergoing OPCABG through down-regulating the expression of myocardial TNF- mRNA and ICAM-1 mRNA.

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During the reform of scientific research system the financial and the material resources were centralized and the central laboratory was constructed in cardiovascular Institute & Fu Wai Hospital.The biosafety was implemented thoroughly in this construction process.The brand-new concept war established and the strict rules were formulated through comprehensively study and repeatedly practice.In the meantime,the advanced management and the operation mode were established.A new biosafety lab was constructed under these conditions.

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<p><b>OBJECTIVE</b>To investigate the association between the severity of coronary arteries in patients with coronary artery disease and the single nucleotide polymorphisms of MMP-3 gene.</p><p><b>METHODS</b>One thousand and three hundred seventy-one patients with coronary artery disease (CAD) diagnosed by coronary angiography and six hundred and ninety-five healthy controls without CAD were enrolled in this study. The SNPs of -1612 5A/6A, -376C/G, Glu45Lys of MMP-3 were genotyped by restriction fragment length polymorphism analysis (RFLP) in all subjects. Univariate analysis was applied to measure the association of the single nucleotide polymorphisms with the severity of coronary arteries.</p><p><b>RESULTS</b>The minor allele frequency of -1612 5A/6A was 0.189, 0.185, 0.183 and 0.152 (P < 0.05 vs. non-CAD control and single stenosis), the minor allele frequency of -376C/G was 0.311, 0.329, 0.326 and 0.325, and the minor allele frequency of Glu45Lys was 0.367, 0.423, 0.417 and 0.405 in non-CAD control, CAD patients with single, two and three vessels stenosis, respectively. 5A allele frequency is significant lower in the group with three vessels stenosis than in non-CAD control and CAD patients with single vessel stenosis (OR = 0.74, P = 0.04). The 5A/5A and 5A/6A genotypes frequency is significant lower in the group with three vessels stenosis than in the non-CAD group and CAD patients with single vessel stenosis (OR = 0.74, P = 0.04).</p><p><b>CONCLUSIONS</b>The single nucleotide polymorphism of -1612 5A/6A of MMP-3 gene may be associated with the severity of coronary atherosclerosis in the Chinese Han patients with coronary artery disease, and the 5A allele might therefore, play a protective role on the progression of coronary atherosclerosis.</p>

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<p><b>OBJECTIVE</b>To study the inhibitory effect of RNA interference (RNAi) on c-myc expression in hepatocellular carcinoma cell line, HepG2.</p><p><b>METHODS</b>Expression vector of c-myc gene-targeting small interference RNA (siRNA) was constructed (psilencer-c-myc) and transfected into HepG2 cells by lipofectamine, and the unloaded vector was used as control (mock). The expression of c-myc mRNA and protein was identified by quantitive PCR and Western blot. Apoptosis of the transfected cells was examined by flow cytometry and immunofluorescent microscopy.</p><p><b>RESULTS</b>After HepG2 cells were transfected with psilencer-c-myc, the expression of c-myc mRNA and protein was suppressed with an inhibition rate of 67% compared with the mock-transfected cells. Apoptosis was identified in the transfected HepG2 cells.</p><p><b>CONCLUSION</b>The expression of c-myc at transcriptional and translational levels in HepG2 cells transfected with siRNA is markedly inhibited, which may be associated with the induction of apoptosis.</p>

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