<Emphasis Type="Italic">In vitro</Emphasis> anti-hepatitis B virus effect of <Emphasis Type="Italic">Hypericum perforatum L</Emphasis>.

The anti-hepatitis B virus(HBV)effects and its mechanisms of the ethanol extracts of Hypericum perforatum L.(EHP)in vitro were explored.HepG2 2.2.15 cells,a stable HBV-producing cell line,were cultured as the model system to observe the anti-HBV effect.The viral antigens of cellular secretion,HBsAg and HBeAg,were determined by enzyme linked immunosorbent assay(ELISA).The quantity of HBV-DNA released in the supernatant was assayed by real-time PCR.In order to understand the mechanisms of the suppression of H...     

表皮生长因子促进小鼠未成熟卵母细胞体外成熟的实验研究

目的 了解表皮生长因子(epidermal growth factor,EGF)对小鼠未成熟卵母细胞体外成熟、受精及胚胎发育的影响.方法 将生殖泡(germinal vesicle,GV)期卵母细胞分别在EGF浓度为0(对照)、0.5、1、2.5、5、10 ng/ml的培养液中进行体外培养,观察生殖泡破裂(germinal vesicle breakdown,GVBD)和第一极体(the first polar body,PB1)排出的情况.将达到MⅡ期的卵母细胞进行体外受精,观察原核和胚胎发育情况.结果 EGF浓度为1、2.5、5、10 ng/ml组GVBD发生率高于对照组;EGF浓度2.5、5、10 ng/ml组PB1排出率高于对照组,其中EGF浓度5 ng/ml组的GVBD、PB1发生率最高(P＜0.01).卵母细胞在1、2.5、5、10 ng/ml EGF培养浓度下的退化率低于对照组(P＜0.05,P＜0.01).卵母细胞的体外受精率、2-细胞和4-细胞胚胎的发生率在EGF浓度为5 ng/ml时明显高于对照组(P＜0.01).结论 EGF可促进GV期卵母细胞的成熟,对其受精能力和胚胎发展也有促进作用,也可能有抑制卵母细胞凋亡的作用,而EGF以上作用与剂量有关.     

The effect of brain-derived neurotrophic factor on angiogenesis

To investigate the in vitro and in vivo proangiogenic effects of brain-derived neurotrophic factor （BDNF）, human umbilical vein endothelial cells （HUVECs） were isolated and cultured in primary culture. The effect of BDNF on the proliferation of HUVECs was examined by MTT assay. The effects of BDNF on HUVEC migration and tube formation were studied by modified Boyden cham- ber assay and tube formation assay, respectively. Matrigel plug assay and chorioallantoic membrane assay were used to evaluate the effects of BDNF on angiogenesis in vivo. Our results showed that BDNF substantially stimulated the migration and tube formation of HUVECs in vitro, although it did not induce HUVEC proliferation. BDNF also induced angiogenesis both in matrigel plug of mouse model and in chick chorioallantoic membrane. In conclusion, BDNF can promote angiogenesis both in vitro and in vivo, and may be a proangiogenic factor.     

HBsAg/HBsAb double positive hepatitis B virus infection model <Emphasis Type="Italic">in vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis>

The pathogenesis of HBsAg （＋）/HBsAb （＋） double positive hepatitis B virus infection was investigated by simulating HBsAg/HBsAb coexistence in vitro and establishing HBsAg/HBsAb double positive model in vivo. Eukaryotic expression plasmids PCI-SY, PCI-adw, PCI-adr, PCI-ayw, which expressed S gene product of different serotypes, were constructed and transfected into HepG2 cells. Recombinant proteins were purified from the transfected cells. At the same time, HBsAg mouse antiserum was obtained by immunizing mice with PCI-SY plasmid. HBsAg/HBsAb coexistence was simulated using these antigens and antiserum. Furthermore, the expression plasmids expressing different serotypes of S gene product including PCI-adw, PCI-adr, and PCI-ayw were injected into mice via tail vein. HBsAg and HBsAb in mice sera were tested at the first and 7th day respectively after antigen plasmids injection. Both in vitro simulation and in vivo animal models demonstrated that HBsAg antigen and HBsAb of the same serotypes Could not coexist, but HBsAg antigen and HBsAb of different serotype could coexist. HBsAg/HBsAb double positive hepatitis B virus infection could be due to infection of viruses of different serotypes.     

Effect of VEGF on neural differentiation of human embryonic stem cells <Emphasis Type="Italic">in vitro</Emphasis>

The effects of vascular endothelial growth factor （VEGF） on neural differentiation of human embryonic stem cells （hESCs） in vitro and the possible mechanism were observed. The hESCs lines, TJMU1 and TJMU2, were established and stored by our laboratory, hESCs differentiated into neuronal cells through embryonic body formation. In this induction process, hESCs were divided into three groups： group A, routine induction; group B, routine induction＋10 ng/mL VEGF; group C, routine in- duction＋10 ng/mL VEGF＋10 ng/mL VEGFR2/Fc. OCT4, Nestin and GFAP in each group were de- tected by RT-PCR, and the cells expressing Nestin and GFAP were counted by immunofluorescence. The percentage of Nestin positive cells in group B was significantly higher than in groups A and C, while the percentage of GFAP positive cells in group B was significantly lower than in groups A and C （P〈0.01）. There was no significant difference between groups A and C （P〉0.05）. It was concluded that VEGF, via VEGFR2, stimulated the neural differentiation of hESCs in vitro.     

Fluoroquinolone resistance and mutation patterns in <Emphasis Type="Italic">gyrA</Emphasis> and <Emphasis Type="Italic">parC</Emphasis> genes in <Emphasis Type="Italic">Neisseria gonorrhoeae</Emphasis> isolates from Shanghai,China

In order to study the resistance of Neisseria （N.） gonorrhoeae to the fluoroquinolone and detect mutation patterns of quinolone resistance-determining regions （QRDRs） of clinical isolates in Shanghai, China, a total of 80 clinical isolates of N. gonorrhoeae were consecutively collected from Shanghai. The MIC of fluoroquinolone for the isolates was examined by using the agar dilution method and the mutation profiles of the QRDRs of gyrA and parC were analyzed by sequencing and restriction fragment length polymorphism （RFLP）. Chi-square test was used for comparison of the t：nutation patterns. The results showed that： （1） High percentages of the 8 isolates were resistant to ciprofloxacin （95.0%）, ofloxacin （95.0%） and lomefloxacin （97.5%）, only one strain was susceptible to the ciprofloxacin. （2） Sensitive strains had a substitute of Asp95→Ala in the gyrA, and all isolates that were resistant or intermediated to the ciprofloxacin, had a double mutation in the gyrA （Ser91, Ala 92 and Asp95）. Some strains also had a mutation in the parC. （3） The MICs of these isolates were significantly associated with the mutation patterns in the gyrA and parC. A double mutation of gyrA combined with parC87 mutation was a predominant pattern in Shanghai and could mediate high level resistance to ciprofloxacin. It suggests that mutations in the QRDRs of gyrA and parC may be responsible for the fluoroquinolone resistance. And fluoroquinolone could not be used as the first line antibiotics for gonorrhea treatment any more in Shanghai, China.     

Influence of silencing TRAF6 with shRNA on LPS/TLR4 signaling <Emphasis Type="Italic">in vitro</Emphasis>

This study investigated the influence of silencing TRAF6 with shRNA on lipopolysaccharide(LPS)/toll-like receptor(TLR)-4 signaling pathway in vitro.Four plasmids(pGCsi-TRAF6-shRNA1,2,3,4) containing different shRNA sequences were designed and synthesized.The proliferation of RAW264.7 cells after transfected with these plasmids was measured by MTT assay.Inflammatory cellular models were established by LPS stimulation.Levels of TNF-α,IL-1β and TGF-β1 in the supernatants,mRNA expressions of TRAF6,IL-6 and COX-...     

脑源性神经营养因子在抑郁症发作病理机制中的作用

抑郁症的脑源性神经营养因子(BDNF)假说认为,BDNF减少在抑郁症的病理生理机制中起着重要的作用,而且其恢复可能与抗抑郁治疗有关.该理论已经得到了越来越多的新证据证明.BDNF能通过多种途径调控神经细胞的发生、生存、生长、分化和凋亡,并直接参与了神经突触的可塑性和重构,这可能是BDNF参与抑郁症发病和治疗的重要机制.该文就近来的BDNF与抑郁症的相关研究进行综述.     

<Emphasis Type="Italic">In vitro</Emphasis> study on human trophoblast cells infected with HCMV

Human trophoblast cells were isolated and cultured in vitro in order to investigate possible pathogenesis of intrauterine infection caused by HCMV.Trophoblast cells were obtained by compound enzymes digestion and discontinuous percoll gradient.Cells and purity were identified by using immunocytochemistry assay with anti-CK7,Vim and β-hCG antibodies.HCMV AD169 strain replication in isolated trophoblast cells and cell apoptosis were detected at different time points post infection(p.i.).The results showed tha...     

<Emphasis Type="Italic">cagA</Emphasis> and <Emphasis Type="Italic">vacA</Emphasis> status and influence of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> infection on serum oxidative DNA damage in Iranian patients with peptic ulcer disease

Background  

Infection with Helicobacter pylori strains may result in different pathological manifestations and increased oxidative stress leading to a strong inflammatory response in gastric mucosa.     

Reversal of multi-drug resistance by vector-based-ShRNA-Mdr1 <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis>

In order to investigate the effects of vector-based hairpin small interference RNA （shRNA） on the reversal of multi-drug resistance （mdr） of A2780/Taxol cells, a novel vector pEGFP-HI/mdrl containing mdrl-shRNA targeting at position 2943-2963 of mdrl was designed and synthesized. Subsequently, A2780/Taxol cells were transfected with pEGFP-H1/rndrl, and the expression ofmdrl mRNA and P-gp was detected by using RT-PCR and Western blot respectively. MTT was used to measure the 50% inhibition concentration （IC50） of Taxol to A2780/Taxol cells. The results showed that at the 24th and 48th h after transfection, the expression of mdrl mRNA was decreased to （52.1±1.0）% and （0.01±1.7）%, and that of P-gp decreased to （88.3±2.1）% and 0%, respectively. At the 48th h after transfection, the relative reversal rate of A2780/Taxol cells to Taxol was 69.54%. In vivo, the nude mice xenografts were injected with pEGFP-H1/mdrl, and then administrated Taxol. The tumor volume in pEGFP-H1/mdrl-transfected group was significantly reduced as compared with that in blank control group or pEGFP-Hl-transfected group （807.20±103.16 vs 1563.78±210.54 or 1480.78±241.24 mm^3, both P〈0.01）. These results suggested that transfection of pEGFP-HI/mdrl could efficiently down-regulate the expression of mdrl mRNA and P-gp in A2780/Taxol cells, and effectively restore the sensitivity of A2780/Taxol ceils to Taxol both in vitro and in vivo.     

A novel sequence-based <Emphasis Type="Italic">coa</Emphasis> genotyping method to discriminate nosocomial methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> isolates

Aim  

To evaluate a novel sequence-based coa typing method in classification for nosocomial methicillin-resistant Staphylococcus aureus.     

电针对抑郁模型大鼠五羟色胺及脑源性神经营养因子的影响

目的:观察电针对抑郁模型大鼠5-羟色胺(5-HT)、脑源性神经营养因子(BDNF)表达水平的影响,探讨电针改善大脑功能可能存在的机制.方法:采用慢性应激抑郁模型,将大鼠分为空白对照组、抑郁模型组、阳性西药组、电针治疗组(以电针刺激百会、印堂穴);Elisa法检测各组大鼠海马内5-HT含量、Western-blot法检测海马内BDNF蛋白表达水平.结果:给予慢性应激刺激后,模型组大鼠海马5-HT含量较正常组显著减少(P＜0.01),电针组大鼠海马5-HT含量较模型组显著增加(P＜0.01).Western-blot印迹结果显示与正常组相比,模型组BDNF蛋白表达量显著降低(P＜0.01);电针组BDNF蛋白表达量较模型组显著增加(P＜0.01).结论:提高海马内5-HT含量及BDNF表达,增强神经可塑性是电针抗抑郁可能的机制.     

脑源性神经营养因子在抑郁症发作病理机制中的作用

抑郁症的脑源性神经营养因子（BDNF）假说认为,BDNF减少在抑郁症的病理生理机制中起着重要的作用,而且其恢复可能与抗抑郁治疗有关。该理论已经得到了越来越多的新证据证明。BDNF能通过多种途径调控神经细胞的发生、生存、生长、分化和凋亡,并直接参与了神经突触的可塑性和重构,这可能是BDNF参与抑郁症发病和治疗的重要机制。该文就近来的BDNF与抑郁症的相关研究进行综述。     

慢性应激大鼠脑源性营养因子的表达分析

目的 探讨慢性不可预知轻度应激(CUMS)大鼠模型各脑区脑源性神经营养因子(BDNF)的表达及抗抑郁药对BDNF表达的影响.方法 将24只雄性SD大鼠随机分为三组(n=8):A组为对照组;B组为CUMS应激组;C组为CUMS应激+西太普兰用药组(每天腹腔注射西酞普兰水溶液2 mL,10 mg/kg).实验为期6周,每周称量大鼠体质量,每3周测试大鼠的糖水偏爱度,造模前及造模6周末通过旷场试验评价大鼠行为.6周后处死大鼠获取脑组织,采用Real-Time PCR检测各脑区BDNFmRNA表达水平.结果 第6周末,B组大鼠的糖水偏爱度明显低于A、C两组(P＜0.05)且行为增多.应激实验开始后,B、C两组大鼠体质量均明显低于A组(P＜0.05).B组BDNF mRNA在海马中的表达高于A组,但差异无统计学意义(P=0.07);C组纹状体中BDNF mRNA表达明显低于A组(P＜0.05).结论 慢性应激可能引起海马BDNF表达升高,抗抑郁药物可能导致纹状体BDNF表达降低.     

Neurogenic differentiation of murine adipose derived stem cells transfected with EGFP <Emphasis Type="Italic">in vitro</Emphasis>

Some studies indicate that adipose derived stem cells(ADSCs)can differentiate into adipogenic,chondrogenic,myogenic,and osteogenic cells in vitro.However,whether ADSCs can be induced to differentiate into neural cells in vitro has not been clearly demonstrated.In this study,the ADSCs isolated from the murine adipose tissue were cultured and transfected with the EGFP gene,and then the cells were induced for neural differentiation.The morphology of those ADSCs began to change within two days which developed i...