RESUMO
Objective To detect the expression of human telomerase reverse transcriptase (hTERT ) and telomerase in hu‐man fetal gastric fibroblasts .Methods Human fetal gastric fibroblasts were isolated and cultured ,epithelial cells were exduded by CK‐18 immune staining .hTERT protein was determined by indirect immunofluorescence .Telomerase activity was analyzed using telomeric repeat amplification protocol assay (TRAP)while the same analysis in adult gastric fibroblast ,which as to be positive con‐trol .Results Cultured fibroblasts were CK‐18 negative .The positive hTERT immunostaining was detected in both cellular cyto‐plasm and nuclear compartments .Amplified telomeric repeats (about 170 bp) in human fetal gastric fibroblasts were longer than those (160 bp) in adult gastric fibroblasts .Conclusion hTERT and telomerase were expressed in human fetal gastric fibroblasts .
RESUMO
OBJECTIVE To discuss the prevention and control measures for nosocomial transmission of Mycobacterium tuberculosis.METHODS The status of hospital-acquired tuberculosis and influencing factors on nosocomial transmission of M.tuberculosis at home and abroad were analyzed.Then prevention and control measures for nosocomial tuberculosis were brought forward.RESULTS To prevent and control of nosocomial transmission of M.tuberculosis,it was necessary to strengthen personnel management and environmental monitoring,control the direction of air flow in hospitals,strengthen respiratory protection of health care workers and management of tuberculosis patients.CONCLUSIONS To prevent and control M.tuberculosis hospital infections,comprehensive prevention and control measures are needed.
RESUMO
There is a kind of intrinsic correlation between achievements and age.The average years of age of the scientists awarded the Nobel prizes in five fields are 30.9~33.3.Lots of ancient and modern scientists in many fields are similar to this.Therefore young people are able to make significant achievements,especially innovative achievements.This law is not well cogitated in our country,especially by the young themselves.To understand this law correctly will be of certain inspiration and significance not only for people from different age bracket to make achievement but also beneficial to improving the innovative capability of the whole country.
RESUMO
Objective To observe the injuries of sodium citrate plasma(scP) on the growth and function of HepG2 cells.Methods The HepG2 cells were cultured.The viability,cell cycle and apoptosis,the leakage of LDH,total protein,glutathione and the changes on morphology of hepatocytes exposured to scP were investigated.Results The viability of HepG2 cells was inhibited when the cells were cultured in scP for 24h(F=37.108,P=0.001).After 48h,nearly all cells died except cells in 10% scP group.After the cells were exposed to scP for 24h,the percentage of S phase of the cell cycle and the rate of apoptosis were significantly increased compared to those of the control.The leakages of LDH were increased in the HepG2 following exposure to scP for 5h(P
RESUMO
Objective To examine and analyze the methylation status of the promoter region of human telomerase reverse transcriptase(hTERT)in gastric cell lines.Methods Telomerase activity was detected with telomeric repeat amplification protocol(TRAP).Expression of hTERT was observed by immunofluorescence.The target sequence of hTERT CpG island(-692~-403bp)was selected by database search.The methylation status of hTERT CpG island was examined with bisulfite sequencing PCR(BSP)as following:Genomic DNAs were modified by sodium bisulfite and amplified by PCR with primers that contained no CpG sites.Direct sequencing was performed for each case.Results Both TRAP and immunofluorescence analysis showed that high levels of telomerase and hTERT were expressed in SGC-7901 and BGC-823 cells.The sequences(-634~-403bp)of hTERT gene promoter,which were sequenced successfully,were homologous to the sequences before sodium bisulfite modification.25 CpGs in BGC-823 cell line and 26 CpGs in SGC-7901 cell line were observed to be methylated in all 26 CpGs of this part.Only one repressive transcription factor,which called myeloid-specific zinc finger protein 2(MZF-2),was found to bind this region which possessed two special binding motifs.Such a kind of binding showed potential importance for methylation-mediated derepression of hTERT transcription.Conclusion The hypermethylation may change the structure of DNA and result in abortive binding between MZF-2 and its motif,which might be one of the reasons for up-regulation of hTERT transcription and telomerase activity.