Objective To detect the Yersinia pestis plasmid and molecular weight along the Qinghai-Tibet Railway.Methods Yersinia pestis plasmids molecular weight detected and analyzed using alkaline lysis,phenol-chloroform extraction of Yersinia pestis plasmid by agarose gel electrophoresis.Results The 18 Yersinia pestis strains of Qinghai-Tibet Railway contained 6×106,45×106,52×106,65×106,92×106plasmid,varing in the range of the 52×106-92×106.Conclusions The Yersinia pestis of Qinghai-Tibet Railway has a standardplasmid graphics,with the biggest Yersinia pestis plasmid changing in a certain regular degree,which providessignificance in the study of plague natural foci of the spatial structure and the genetic.characteristics of Yersiniapestis.

Objective To explore the effect of HeLa cells infected with Coxsackie virus B3 (CVB3) on the changes of mTOR signal pathway under different nutritional conditions.Methods The HeLa cells were cultured under conventional culture and serum starvation culture.(1) For the conventional method,the medium with 10 g/L fetal bovine serum was added for 24 h after the Hela cells were fused into 40％ to 50％,and the medium was changed on the next day,then the virus group was infected with CVB3 of 50％ tissue culture infective dose (TCID50).However,the control group was cultured by 2 g/L fetal bovine serum.(2) For the serum starvation method,HeLa cells were cultured with the medium without fetal bovine serum for 24 h.Then the virus group was infected with CVB3 of TCID50.The cells in control group were cultured by 2 g/L fetal bovine serum.Cell morphology changes were observed by inverted microscope,and the expressions of the mTOR,p70S6K mRNA were detected with Real-time PCR at 3 h,6 h,9 h,12 h,24 h respectively in both conventional culture and serum starvation groups.Results The expressions of mTOR and p70S6K mRNA were lower in the virus group than those in control group at 12 h and the 24 h (all P ＜0.05) in the conventional culture group.And the expressions of mTOR and p70S6K mRNA in the virus group were lower than those in the control group at every time points (all P ＜ 0.05) in serum starvation group.The expressions of mTOR and p70S6K mRNA in group with serum starvation virus and the control groups were higher than those in conventional culture group in all time points,but only the expressions of mTOR mRNA were significantly different between the 2 groups (all P ＜0.05),however,the expressions of p70S6K mRNA had no significant difference between the 2 groups (all P ＞ 0.05).Conclusion CVB3 may be able to down-regulate the expressions of mTOR and p70S6K mRNA.

Objective To investigate wingless-type MMTV integration site family,member 10A (WNT10A) expression in human dental pulp tissues and human dental pulp cells (HDPC).Methods Human premolars or wisdom teeth were obtained fron healthy individuals extracted for orthodontic purpose.The expression of WNT10A and the molecules of Wnt signaling pathway in human dental pulp tissues were analyzed by immunohistochemistry and semi-quantitative reverse transcription-PCR(RT-PCR).HDPC were primarily cultured from pulp tissues of healthy premolars or wisdom teeth and passaged cells.Their growth patterns were observed by microscopy.The expression levels of Wnt molecules and odontoblast-specific biomarkers during different cell passage were determined by semi-quantitative and real-time quantitative RT-PCR.Results The immunohistochemical analysis showed WNT10A was located in the cytoplasms of odontoblasts.WNT10A,axis inhibition protein 2(AXIN2),Dickkopf(DKK1),lymphoid enhancer factors 1 (LEF1),low density lipoprotein receptor-related protein 4 (LRP4),dentin sialophoshoprotein (DSPP),alkaline phosphatase(ALP) and osteocacin were detected in the pulp tissues by RT-PCR.HDPC reached confluence in 15 days.The 4th passage of HDPC proliferated actively,with clear cytoplasms and uniformly stretches.The 9th passage of HDPC tended to die.The Wnt signaling pathway downstream molecules were expressed in HDPC throughout the subculture.DSPP expression at mRNA level was detected peaking in the 4th passage(0.4178 ±0.0076).The expression levels of WNT10A in the 5th and the 9th passage(4.97 ±2.83,4.70 ±4.06) were significantly higher than in the 2th and the 4th passage (0.84 ± 0.66,0.70 ±0.45) (P ＜ 0.05).Conclusions Wnt signaling pathway mediated by WNT1 0A was activated in pulp tissues and HDPC,indicating that WNT10A could be involved in differentitation of odontoblasts and dentin formation.

A new hexaketide acid esterified by the 17-hydroxyl group of 16,17-dihydroxycyclooctatin, namely 17-[16,17-dihydroxycyclooctatinyl]-hexaketide ester (1), a member of the group of rare bacterial diterpenes with a fused 5-8-5 ring system was isolated from strain Streptomyces sp. SR107. The structure was determined on the basis of its spectral data (H NMR, C NMR, H-H COSY, HSQC, HMBC, NOESY, IR and HR-ESI-MS). The antibacterial activity was also evaluated in this paper.
Anti-Bacterial Agents ; chemistry ; pharmacology ; Bacteria ; drug effects ; Diterpenes ; chemistry ; metabolism ; pharmacology ; Esters ; chemistry ; pharmacology ; Magnetic Resonance Spectroscopy ; Molecular Structure ; Streptomyces ; chemistry