Objective:To explore the effect of leptin on proliferation of human hepatocellular carcinoma cells Huh 7 and its probable molecular mechanism.Methods:The human hepatocellular carcinoma cells Huh 7 cultured in vitro was treated with leptin at different concentrations.The proliferation of the cells was measured by MTT assay.The cell cycle was monitored by flow cytometry analysis(FCM).The expression of cell cycle regulatory proteins Cyclin D1 and P21waf1 were determined by immunocytochemistry and imageanalysis system,and real-time quantitative PCR.Results:Leptin significantly raised the proliferation rate of Huh 7 cells.The effect was dose and time-depended partly.Leptin promoted Huh 7 cells in entering the S phase from the G0/G1 phase.mRNA of Cyclin D1 in the leptin treated Huh 7 cells was increased,as compared with that in the control cells(P

Bacterial resistance to antibiotics is currently a serious health concern.According to the data from the surveil-lance of bacterial resistance in China ( CHINET) ,the isolation rates of gram-negative bacteria have been rising annually. Among the gram-negative organisms, the isolation rate of Carbapenem-resistant enterobacteriaceae, especially extensive drug-resistant strains,has been increasing rapidly.The isolation rate of extensive drug-resistant or pandrug-resistant non-fermenting bacteria,es-pecially Acinetobacter baumanii,is still relatively high.These extensive drug-resistant gram-negative bacteria cause high mortality, which has drawn great attention in clinical settings.On the part of multidrug-assistant gram-positive bacteria,the isolation rate of vancomycin-resistant enterococci remains stable but rates of methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococci are still high.Staphylococcal strains have not yet been found resistant to vancomycin in China.Understanding the epi-demiology of local drug-resistant bacteria facilitates the development of appropriate antibiotic strategies. The mortality of patients with severe infection may be improved by early use of antibiotics and appropriate de-escalation therapy.Rational use of antibiotics and recognition of the influence factors,such as antibiotic-induced endotoxin release,may maximize the efficacy of antibiotics and minimize the adverse reactions.

OBJECTIVE To study the clinical feature among patients with infectious fever and the antimicrobial resistance of infection pathogens.METHODS A retrospective analysis was carried out among 70 cases during recent 3 years.RESULTS The 70 strains of pathogens were isolated from blood and/or bone marrow cultures of 70 patients with infectious fever,40 strains(57.1%) were Gram-positive cocci,in which 8 strains were Staphylococcus aureus,and 32 strains were coagulase negative staphylococci(CONS);30 strains(42.9%) were Gram-negative bacilli,of which the Salmonella and Escherichia coli were the main microorganisms,53.1% of CONS were resistant to oxacillin.There were 5 strains of Gram-negative bacilli that were suspected to produce extended spectrum ?-lactamases(ESBLs),which were resistant to multiple antibiotics,the most active agent against these Gram-negative bacilli with ESBLs was imipenem.CONCLUSIONS The bacteria are mainly Grampositive cocci for the patients with infectious fever in the infectious wards.The Gram-negative bacilli with ESBLs show more multi-drug resistance,we should rationally select antibiotics and decrease the occurrence of drug resistant strains.

Objective To construct and identify the specific interference vector for second mitochondria -derived activator of caspase (SMAC)gene in mice and perform lentiviral packaging.Methods According to the SMAC gene sequences in mice,three small interfering RNAs (siRNAs)(siRNA1,siRNA2,and siRNA3)and one negative control sequence (siRNAn)were designed and synthesized,and mouse hepatocytes were transfected with the above siRNAs using Lipofectamine 2000.The inhibitory effects of these siRNAs on SMAC mR-NA expression were evaluated by real-time PCR,and the optimal siRNA was screened out accordingly.Oligo DNA was synthesized based on the optimal siRNA and then connected to GV1 15 vector to obtain recombinant interference plasmid.The candidate clones were identified by PCR and sequenced.The recombinant interference plasmid,as well as pHelper 1.0 and pHelper 2.0,was used to transfect 293T cells for lentivirus packaging.Then,cell supernatants were collected and concentrated,and the lentiviral titer was determined by gradient dilution. Comparison between groups was made by analysis of variance,and multiple comparisons were made by SNK-q test.Results The three siRNAs had different inhibitory effects on SMAC mRNA expression in hepatocytes;siRNA1 showed the strongest inhibitory effect,with an inhibition efficiency of 70.3%.Based on siRNA1 ,the oligo DNA was successfully synthesized and correctly connected to the lentiviral vec-tor,as proved by sequencing.The lentiviral titer was 6 ×108 TU/ml,as determined by gradient dilution.Conclusion The recombinant lentivirus that inhibits SMAC expression in mice has been constructed successfully,laying the foundation for further studies on the role of SMAC gene in liver failure.

Survivin, a newly identified member of IAP family, is a powerful apoptosis-inhibiting factor. It is expressed in embryonic tissues as well as in the majority of human cancers, but not in most normal adult tissues. The cancer-specific expression of survivin makes it a potential target for cancer treatment. A survivin-specific small inhibitory RNA (siRNA) was introduced into hepatocellular carcinoma cells to investigate its effect on cancer cell apoptosis, growth and sensitivity to chemotherapeutic drugs. It was found that expressions of survivin protein and proliferation index (PI) in siRNA groups were significantly decreased, the apoptosis index (AI) of siRNA groups was significantly higher than those of others groups, and the growth inhibition rate (GIR) of chemotherapeutic drugs in siRNA groups were significantly higher than those of other groups. Our study suggests that the expression of survivin may be significantly decreased in hepG2 cell after siRNA transfection. siRNA targeting survivin could induce cell apoptosis, inhibit cell proliferation and sensitize hepatocarcinoma cells to chemotherapy. Our findings provide preliminary evidence for the therapeutic use of survivin-targeted RNA interference for human tumors that express high levels of this molecule.
Apoptosis ; Cell Proliferation ; Gene Knockdown Techniques ; Hep G2 Cells ; Microtubule-Associated Proteins/*genetics ; Microtubule-Associated Proteins/metabolism ; RNA Interference ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; RNA, Small Interfering/*genetics ; RNA, Small Interfering/metabolism

To investigate HCV extrahepiatic infection and replication site as well as its relation with liver damage,bone-marrow mononuclear cells from 20 cases of nutreated chronic hepatitis C virus infect- ed patients were studied by digoxin-labeled in situ hybridization.Positive HCV RNA stained were de- tected in 18 of 20 cases (90%).Negative HCV RNA stained were not detected in any cases.The results suggested that there was HCV RNA in the bone-marrow of the patients with hepatitis C and bone-mar- row could be infected by HCV.But bone-marrow cell is not the HCV replication site.This study has some significance in HCV elucidating the pathogenicity of as well as the pathogenesis of chronic hepatitis C.

Objective To investigate the effect of 20‐HETE on the isolated myocardial ischemia reperfusion injury and to ex‐plore its underlying mechanisms .Methods Experiments were performed in isolated rat hearts subjected to 35 min of ischemia fol‐lowed by 40 min of reperfusion in Langendorff preparations .HET0016 (1 μmol/L) and various concentrations (10 ,30 or 50 nmol/L) of 20‐HETE were infused 10 min before the onset of ischemia and throughout the reperfusion period .Cardiac hemodynamic changes and myocardial contractility were continuously recorded with the Powerlab /8P system .Myocardial infarct size was meas‐ured by TTC staining .The level of ROS and the protein carbonyl content were determined by DHE fuorescence and DNPH method , respectively .Results Perfusion with HET0016 significantly improved myocardial ischemia reperfusion injury reduction in cardiac contractility ,after inhibited the production of 20‐HETE significantly reduced the occurrence of myocardial infarction area (P<0 .05) ,but exogenous join 20‐HETE aggravated I/R‐induced myocardial injury (P<0 .05) .Myocardial ischemia reperfusion injury significantly increased production of ROS and oxidative stress ,both of which were significantly inhibited by HET 0016 and enhanced by 20‐HETE administration(P< 0 .05) .Conclusion 20‐HETE stimulates ROS production and enhance protein carbonylation , which aggravates myocardial ischemia reperfusion injury .

To examine the effect of Gankang Suppository on duck hepatitis B virus (DHBV), the serum biochemistry and hepatic histology in an animal model of DHBV infection, a model of DHBV infection was established by infecting 1-day-old Yingtaogu ducklings with DHBV-positive serum. The successful model was confirmed by PCR assay and 48 ducklings infected with DHBV were randomly divided into 3 groups: a Gankang Suppository treatment group, an acyclovir (ACV) group and a DHBV model group (control), with each group having 16 animals. All the animals were given the medicines for 4 weeks in a row. The serum of the animals was taken 14 and 28 days after the medication and 7 days after drug discontinuation. Real-time PCR was performed to detect the copy numbers of DHBV DNA in the serum. ALT and AST were dynamically monitored. The ducklings were sacrificed on the 7th day after the discontinuation of the treatment and livers were harvested and examined for inflammation and degeneration of liver cells by using HE staining. The results showed that on day 14, 28 after the treatment and day 7 after the withdrawal, the logarithmic values (log) of DHBV DNA copy numbers in ducklings of Gankang Suppository treatment group were significantly lower than that before the treatment (P=0.0092, P=0.0070, P=0.0080, respectively). Compared with DHBV model control group, the ALT level was significantly decreased (P=0.0020, P=0.0019, respectively) on day 28 after the treatment and on day 7 after the withdrawal. The AST level was also reduced on day 14 after the treatment (P=0.0298). Compared with the ACV control group, the level of ALT was lower on day 7 after the withdrawal (P=0.0016). Histologically, the hepatocyte swelling, vacuolous degeneration and acidophilic degeneration in Gankang Suppository treatment group were alleviated 7 days after the withdrawal as compared with model control group (P=0.0282, P=0.0084, P=0.0195, respectively). It is concluded that Gankang Suppository can effectively suppress DHBV replication, reduce the levels of serum ALT and AST and improve hepatic histology.

Objective To study the effect of a new mucA gene mutation on the biofilm formation process and the morphology of matured biofilm of Pseudomonas aeruginosa. Methods The mucA gene of PAO1 was cloned into the Pseudomonas aeruginosa expression plasmid pUCP20. The recombinant plasmid was transformed to mucoid PA17 which contained a new mucA mutation. Positive clones of the plasmids were identified by enzyme digestion and sequencing. The expression levels of algD in the positive clones were assessed by semi-quantitative RT-PCR. The modified plate culture method was used to establish the biofilm models of PA17, PA17 with recombinant plasmid and PAO1 in vitro. Results Transformation was identified by the decreased expression of algD in positive clones. The rate of biofilm formation of the positive clones was between those of PAO1 and PA17. The irreversible adhesion occurred after 8 h and the matured biofilm was observed on day 6. The morphologies of PA17, PAO1 and PA17 with recombinant plasmid were the same. Conclusion The mucA gene mutation of PA17 delays the formation of irreversible adhesion of PA17 biofilm, but it has no effect on the morphology of matured biofilm.

To study the effect of endotoxin on liver apoptosis, L02 liver cells were cultured and passaged in vitro, and then stimulated by endotoxin at 10 mg/mL for 4, 8, 16 and 24 h respectively. Liver apoptosis was flow cytometrically and fluorescently detected. Immunohistochemistry was used to detect the delivery of smac and caspase9. The delivery of liver cell smac and the activity of caspase3 were measured by caspase3 assay kit. The hepatic failure models of rats were established by using D-galactosamine. The blood serum and liver tissues were collected for the detection of the liver function, the level of endotoxin and the activity of caspase3 by using chromogenic substrate limulus amebocyte lysate method (LAL) and caspase3 active assay kit. The expression of smac and caspase9 in liver cells was detected by Western blotting. With in vitro study, the L02 cells stimulated by LPS condensed into conglobation and formed apoptotic bodies. After those cells were stained by hoechst, the apoptotic cells displayed blue color under the fluorescent microscope. The apoptosis rate was increased over time and the apoptosis was mainly of advanced stage. Meanwhile, the rate of smac delivery and activity of caspase9 and caspase3 were increased on L02 cell membrane. In vivo, hepatic failure and obvious endotoxemia were induced by injection of more than 200 mg/kg D-GalN. Hepatic mitochondria smac was reduced with dosage of D-GalN and, on the contrary, the activity of caspase3 was increased. D-GalN at 200 mg/kg increased Caspase9 while D-GalN at 300 mg/kg decreased caspase9. Mitochondria signal channel plays an important role in the endotoxin-induced apoptosis of hepatic cells by promoting the release of smac from mitochondria to cytoplasm and activating caspase9 and caspase3 in its low-level channel.
Apoptosis/*drug effects ; Carrier Proteins/*metabolism ; Caspase 3/metabolism ; Caspase 9/metabolism ; Cell Line ; Cells, Cultured ; Endotoxins/*pharmacology ; Liver/cytology ; Liver/*metabolism ; Liver/pathology ; Liver Failure/chemically induced ; Liver Failure/pathology ; Mitochondrial Proteins/*metabolism ; Rats, Wistar