Objective To investigate the formation of biofilm in clinical isolates of Staphylococcus epidermidis ,and to analyse the correlation between biofilm formation and antibacterial resistance of Staphylococcus epidermidis .Methods A total of 62 strains of Staphylococcus epidermidis isolated from blood specimens of inpatients with bloodstream infection ,from January 2014 to February 2015 ,were collected .The biofilm formation of Staphylococcus epidermidis was detected by using the semi‐quantitative adherence as‐say and polymerase chain reaction(PCR) amplification experiment .The antibacterial susceptibility test was carried out according to K‐B method .Results The positive rate of biofilm formation detected by using the semi‐quantitative adherence assay and PCR for icaA gene were 37 .1% (23 strains) and 43 .5% (27 strains) respectively ,and there was no statistically significant difference(P>0 .05) .There were 14 positive strains detected by both methods .The resistance rates of strains producing biofilm to antibacterial a‐gents were generally higher than those of non‐producing biofilm strains ,and there were statistically significant differences in resist‐ance rates of strains to gentamicin ,penicillin ,oxacillin ,levofloxacin and cefoxitin(P<0 .05) .All bacteria were sensitive to vancomy‐cin ,linezolid and quinupristin/dalfopristin .Conclusion There is no significant difference between the two methods in detecing bio‐film formation .The resistance rates of strains producing biofilm to antibacterial agents were generally higher than those of non‐pro‐ducing biofilm strains .

The effects of epidermal growth factor (EGF) on proliferation of G15 glioma cells and the possible mechanisms were investigated. GFAP and EGFR expression was detected by immunohistochemical method. After the cells were treated with EGF at different concentrations, cell count method was used to determine the proliferation of glioma cells, cell cycle and apoptosis were analyzed by flow cytometry (FCM), and laser scan confocal microscope (LSCM) was used to measure the cytoplasmic free calcium. The results showed that GFAP was diffusedly expressed in GL15 cells and EGFR was over-expressed. EGF at doses of < or =1 ng/mL could significantly stimulate cell proliferation, cells in phase G0/G1 decreased, and those in phase S increased. EGF at doses of 10 and 100 ng/ml could inhibit the cell proliferation significantly, and the apoptosis ratio in high dose of EGF group was higher than in control group. EGF could significantly induce a quick rise of intracellular free calcium, but the peak value of intracellular free calcium activated by high dose of EGF was higher than by low dose of EGF. It was suggested that EGF had a dual effect on gliomas: low dose of EGF could stimulate the cell proliferation of gliomas, but high dose of EGF could induce the cell apoptosis and inhibit the proliferation of gliomas, which might be contributed to the difference of intracellular free calcium.

The effects of RNAi-mediated gene silencing of LRlG1 on proliferation and invasion of the human glioma cell line U251-MG and the possible mechanisms were explored in this study. The plasmids pGenesil2-LRIG1-shRNA1 and pGenesil2-LRIG1-shRNA2 were transfected into U251-MG glioma cells respectively by using Lipofectamine 2000 and the transfected cells in which the LRIG1 expression was stably suppressed were selected by G418. The cells transfected with negative shRNA served as control. The expression levels of LRIG1 mRNA and protein were measured by qRT-PCR and Western blotting, respectively. The cell cycle was analyzed by flow cytometry. The results showed that LRIG1 mRNA expression was reduced by 70% and 58% and LRIG1 protein expression by 58% and 26% in U251-MG cells transfected with pGenesil2-LRIG1-shRNAl and pGenesil2-LRIG1-shRNA2 relative to the negative shRNA-transfected U251-MG cells. The proliferative capacity of the LRIG1 specific siRNA-transfected cells was stronger than that of control cells. Cell cycle analysis showed that silencing LRIG1 significantly increased the percentage of S phase cells and the proliferation index (P<0.01). Moreover, silencing LRIG1 could promote the invasion of U251-MG cells (P<0.05). These findings suggested that LRIG1-targeting siRNA can exert a dramatically inhibitory effect on RNA transcription and protein expression of LRIG1, and LRIG1 down-regulation could promote the proliferation of U251-MG cells, arrest U251-MG cells in S phase, and enhance the invasion of U251-MG cells.

To investigate the cardioprotective effect of formononetin (FMN) on no-reflow (NR) after myocardial ischemia-reperfusion and its molecular mechanism based on integrated pharmacology and experimental verification, firstly, human breast cancer MCF-7 cells and myocardial NR rats were used to confirm the estrogenic activity and the effect of alleviating NR of FMN, respectively. Male SD rats were divided into Sham, NR, FMN (20 mg·kg^-1) and sodium nitroprusside (SNP, 5.0 mg·kg^-1) groups, which were administered once a day for one week, the experiment was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (TCM-LAEC2019095). The pharmacological analysis and in vivo study of NR rats were integrated to reveal the mechanism of FMN improving NR. The results showed that FMN had estrogenic effect and reduced NR by improving cardiac structure and function, reducing NR, ischemic myocardial area and pathological injury of cardiomyocytes. Integrated pharmacology predicts that the mechanism of FMN improving NR is mainly related to phosphatidyinositol-3-kinase-protein kinase B (PI3K-Akt) signal pathway. Phytoestrogens play a role in cardiovascular protection mainly by activating G protein-coupled estrogen receptor (GPER). GPER is also an important regulator in the upstream of PI3K-Akt signaling pathway. This study found that FMN can significantly activate GPER, p-PI3K, p-Akt and phospho-endothelial nitric oxide synthase (p-eNOS). It has good binding ability with GPER and eNOS protein. In this study, through the integration of pharmacology and experimental evaluation, it is revealed that FMN activates PI3K/Akt/eNOS signal pathway by activating GPER, thus significantly improving NR.

Arthritis ; surgery ; Arthroplasty ; methods ; Arthroplasty, Replacement, Hip ; Female ; Humans ; Middle Aged

Objective: To study the influence of negative electrets on apoptosis of fibroblast cells and to probe its mechanism. Methods: Fibroblast cell were treated with -300, -500 and -1 000V PTFE electrets for 24, 48 and 72 h, respectively, and the influence of negative electrets on cell apoptosis was studied by means of flow cytometry and transmission electron microscope. Results: Compared with control group, apoptosis cells increased from 0.5% to 10% (some even to 15%) after 24，48 and 72 h action of -300, -500 and -1 000 V electrets. After action of -500 V PTFE electrets for 48-72 h, fibroblast cells showed characteristic morphological features of apoptosis. These features included chromatin aggregation, nuclear and cytoplasmic condensation and partition of cytoplasm and nucleus into membrane bound-vesicles (apoptotic bodies). The effect of negative electrets on apoptosis was in proportion to the time and electric field intensity. Conclusion: Negative electrets can enhance apoptosis of fibroblast cells.

BACKGROUND: Vertebroplasty (PVP) and kyphoplasty (PKP) are important methods for the treatment of osteoporotic vertebral compression fractures in the elderly. Although bone cement has certain liquidity and vertebral fractures are often in different situations, bone cement leakage rate is still high. OBJECTIVE: Based on the theoretical discussion and clinical analysis, to study the theoretical causes of bone cement leakage and effective prevention methods. METHODS: A total of 162 cases (186 vertebrae) were treated with three methods of vertebroplasty. Group A: 64 cases with 78 vertebrae were treated with conventional cemented vertebroplasty; Group B: 57 cases with 65 vertebrae were treated with cemented vertebroplasty using cement pump; Group C: 41 cases with 43 vertebrae were treated with balloon kyphoplasty. The leakage of bone cement was observed in three groups. RESULTS AND CONCLUSION: Of the 186 vertebrae, postoperative bone cement leakage occurred in 25 vertebrae, with the leakage rate of 13% (25/186). Group A had bone cement leakage in 11 vertebrae, and the leakage rate was 14% (11/78). Group B had bone cement leakage in 8 vertebrae, and the leakage rate was 12% (8/65). Group C had bone cement leakage in 6 vertebrae, and the leakage rate was 14% (6/43). There was no significant difference among the three groups in the leakage rate of bone cement (P > 0.05). That is to say, the causes of bone cement leakage are not completely controllable, and the leakage position has some randomness. Strict and careful imaging monitoring is an intuitive method to prevent bone cement leakage.

AIM: To investigate the potential toxic effects of paclitaxel(PTX)on the proliferation, apoptosis, cell cycle, morphology, and blood-retinal barrier(BRB)of human retinal pigment epithelial cells(ARPE-19).

METHODS: ARPE-19 cells were cultured in vitro and divided into two groups: Control group(Control)and drug plus group(PTX). ARPE-19 cells were treated with different concentrations of PTX(0.005, 0.05, 0.5, 5mg/L)for a certain period of time(12, 24, 36, 48, 72h), and CCK8 assay and flow cytometry were used to detect the effects of drug on proliferation and apoptosis of ARPE-19 cells at different concentrations and time points. The same time, the cell cycle was detected by flow cytometry. Morphological changes of cells were observed by immunofluorescence. Expressions of apoptosis-related proteins and barrier function-related proteins were detected by Western blot. The effect of the drug on the cell barrier was measured by measuring the transepithelial resistance of the cells.

RESULTS: PTX reduced the proliferation ability of ARPE-19 cells. After 36h of treatment with low concentration of 0.005mg/L paclitaxel, cell proliferation began to be affected. At the same time, PTX accelerated cell apoptosis was dependent on drug concentration and time. Flow cytometry showed that the cells were arrested in the G2-M phase. In addition, PTX causes significant morphological changes in cells, with normal cells fusiform or irregular. In the PTX group, the number of cells decreased and the cell shape tended to be round. PTX affected retinal barrier function, and the transepithelial resistance of cells was significantly decreased after treatment, and the expression of tight junction proteins ZO-1 and Occludin were significantly decreased compared with the control group(P<0.05). The expression levels of Cleaved-caspase-3 and Bax were significantly increased compared with the control group, while the expression levels of Bcl-2 were significantly decreased(P<0.05)and was dependent on drug concentration and time.

CONCLUSION: PTX can affect the proliferation and apoptosis of ARPE-19 cells, and it depends on time and concentration. In addition, PTX affected the cell cycle and morphology of ARPE-19 cell. At the same time PTX can destroy the barrier function of the retina,suggesting that anti-tumor drugs have a potential toxic effect on the retina.

The full-length porcine interferon gamma(PoIFN-gamma) cDNA, including the secretion signal peptide coding region was recloned into honor plasmid pFastBac 1 of Bac-To-Bac Baculovirus Expression System. These recombinant plasmids, pFastBac -PoIFN-gamma, were transformed into DH(10Bac) host bacteria to get recombinant shuttle plasmids, rBacmid-PoIFN-gamma. Recombinant baculovirus, rBac-PoIFN-gamma, was generated for expressing PoIFN-gamma, by transfecting rBacmid-PoIFN-gamma with Cellfectin Reagent into sf9 insect cells. The expression of PoIFN-gamma in insect cells was confirmed by Western Blot, indirect immunofluorescence assay and indirect ELISA. The antiviral activity assay shows that PoIFN-gamma expressed by the rBac-PoIFN-gamma can efficiently inhibit the replication of the recombinant Vesicular Stomatitis Virus expressing green fluorescence protein in PK-15 cells. The antiviral activity of PoIFN-gamma can be specifically blocked by anti-PoIFN-gamma mouse serum. The antiviral titer of culture supernatant of insect cells infected by rBac-PoIFN-gamma is 2 x 10(4) IU/mL. The results demonstrat that the rBac-PoIFN-gamma can express rPoIFN-gamma efficiently and rPoIFN-gamma has high antiviral activity.
Animals ; Antiviral Agents ; metabolism ; pharmacology ; Baculoviridae ; genetics ; Blotting, Western ; Cell Line ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect ; Gene Expression ; Green Fluorescent Proteins ; genetics ; metabolism ; Immune Sera ; immunology ; Interferon-gamma ; genetics ; immunology ; metabolism ; pharmacology ; Mice ; Mice, Inbred BALB C ; Microscopy, Fluorescence ; Recombinant Proteins ; Spodoptera ; Swine ; Vesiculovirus ; genetics ; Virus Replication ; drug effects

Objective To establish a height prediction model of Chinese Han male based on the reported 547 height-associated single nucleotide polymorphisms (SNPs) loci in Europeans, and assess its accuracy for height estimation. Methods The DNA typing was analyzed in 59 Han male samples of Shandong province by Affymetrix SNP Array 6.0 chip and HiSeq 4000 sequencing platform. Prediction model was established using 547 height-associated SNPs loci as predictors and weight allele sums (WAS) as com-puting method. The accuracy of height prediction model was analysed using receiver operating characteris-tic (ROC) curve and area under curve (AUC). Results There was no height-associated SNPs locus was found by genome-wide association studies. In present study, height prediction model was established by WAS and obtained an AUC of 0.67 (95％CI:0.53-0.90). Conclusion It has reference value for predicting the height of Han male in Shandong province by WAS model based on 547 SNPs loci, while it is still necessary to further promote the accuracy of the prediction model by screening more height-associated SNPs loci with population heterogeneity.