Background and purpose:More and s’more evidence has demonstrated that DNMT1 was expressed at high levels in many different kinds of human tumor tissues or cells,suggesting that high expression of DNMT1 was closely associated with occurrence and development of tumors.In this study,effect of down-regulation of DNMT1 on cell proliferation and migration ability of esophageal squamous cell carcinoma(ESCC) cell line EC9706 cells was studied and its related mechanism was explored.Methods:Cell proliferation assay was investigated using CCK-8 Kit,cell migration ability was analyzed using Boyden chamber and the expressions of DNMT1 and MMP-2 were detected by Real-time PCR and Western blotting methods.Results:The result of cell proliferation experiment showed that down-regulation of DNMT1 could markedly inhibit cell proliferation in EC9706 cells.After transfection with DNMT1 siRNA,invasiveness and metastasis ability of EC9706 cells displayed an obvious decrease(P

Objective To evaluate the clinical efficacy of MRA in the arteries of the pelvis and lower extremity with automatic table movement (MobiTrak).Methods 12 cases suspected of pelvis and lower extremity artery diseases underwent dynamic 3D contrast enhanced MRA and automatic table movement at the same time.Three cases underwent artery angiography,four cases were detected by operation.Results All diseased arteries were well demonstrated.Among them,lower extremity artery occlusion 8,failing vascular grafts 2,artery aneurysms 2.Conclusion Automatic table movement is of value in assessing pelvis and lower extremity artery diseases accurately.And it is a reliable and potential new technique.

AIM: To construct a recombinant retrovirus vector carrying hTERT for establishing UCBMSCs with hTERT(hTERT-MSCs) to overcome their limited life span and detecting whether telomerized UCBMSCs line maintained long-term self-renewal and differentiation capacity.METHODS: The whole cDNA was generated by PCR amplifications from the plasmid pEGFP-hTERT-C1.The hTERT segments were subcloned into pLNCX2.The target cells were infected with these retroviral particles.The stably transfected cells were selected by neomycin and expanded life span which were designated hTERT-MSCs was observed.The expression of hTERT in mRNA level was detected by RT-PCR and the telomerase activity was measured by TRAP(PCR)-ELISA assay.The hTERT-MSCs were induced with 5-azacytidine to cardiac muscle cells and the specific marker of myocardiocyte was detected.RESULTS: The constructed plasmids were digested with restriction endonucleases(BglⅡand NotⅠ).Two characteristic segments including 6.1 kb and 3.6 kb were obtained.The hTERT-MSCs expressed hTERT in mRNA level.The telomerase activity of hTERT-MSCs was positive.The growth kinetics of hTERT-MSCs was higher than those in UCBMSCs.The hTERT-MSCs were induced to myocardiocyte.CONCLUSION: The hTERT recombinant retrovirus vector has been successfully constructed.The hTERT gene activates the telomerase and prolongs the life-span of cells.No effect of hTERT gene on some type of differentiation potential of MSCs is present.

BACKGROUND:Human mesenchymal stem cells (hMSCs) become aging and even die after several passages. Some investigations have shown that telomere has a close correlation with life span of the cells. Whether the ectopic expression of human telomerase reverse transcriptase (hTERT) could induce the activity of the telomerase, maintain the length of telomere, and finally prolong the life cycle of MSCs without losing their multipotent differentiation capacity is still uncertain.OBJECTIVE: To observe the influence of the ectopic expression of hTERT on the telomerase activity and cell life cycles of hMSCs.DESIGN: Repetitive measurement trails.SETTING: Research Center of Stem Cell, Zhengzhou University Medical College.MATERIALS: The experiment was conducted in the Research Center of Stem Cell, Zhengzhou University Medical College from October 2003 to December 2005. hMSCs were obtained from 20 healthy donators from the Department of Pediatric Surgery and Outpatient, the Third and First Affiliated Hospitals of Zhengzhou University. Enhanced green fluorescent protein plasmid (pEGFP-C1) and pEGFP-hTERT were provided by Dr. Chantal Autexier of Canada. DH5α strain provided by Dr. Hou Wei-hong, the Key Molecular Medical Laboratory of Zhengzhou University Medical College.METHODS.: Under sterile condition, 2 mL bone marrow of sternum of healthy donors were harvested, and prepared after centrifugalization,dilution and passage.① Transfection of pEGFP-hTERT into hMSCs and the screening and amplification of resistance cloning:The 5th passage cells were seeded in a 24-well plate,and transfected by pEGFP-hTERT with lipofectamine method.The cells were divided into four groups including untransfected group,lipofectamine group,pEGFP-C1 group and pEGFP-hTERT group. Resistance cloning screen and amplification was performed by G418. ②hTERT mRNA expression and detection of telomerase activity:RT-PCR and PCR-ELISA were used to detect the hTERT mRNA expressions of the fifth passage hMSCs transfected with pEGFP-hTERT, and pEGFP-C1, the untransfected tenth passage hMSCs and K562 cells (positive control), and the telomerase activity of the fifth and thirtieth passage hMSCs transfected with pEGFP-hTERT,the fifth pEGFP-C1-transfected cells and the tenth passage untransfected cells. ③Karyotype analysis of hTERT-transfected MSCs: Chromosome analysis was performed by conventional Giemsa staining.④Inducement of differentiation from telomerase-positive MSCs into neuron-like cells and RE-PCR identification:The transfected MSCs were cultured in a medium containing epidermal growth factor and basic fibroblast growth factor, which could induce the cells differentiate into neuron-like cells. The culture solution was changed every 3 days, and the changes in cell growth condition and morphologic characteristics were observed under an inverted microscope. The microtubule associate protein (MAP2) and neurofliament subunit M (NF-M) were identified by RT-PCR.MAIN OUTCOME MEASURES:①hMSCs transfection with different kathion liposomes and the screening and amplification of resistance cloning; ②hTERT mRNA expressions of each group and detection of telomerase activity; ③Karyotype analysis of pEGFP-hTERT-transfected MSCs; ④ Induction of differentiation from telomerase-positive MSCs into neuron-like cells and RE-PCR identification.RESULTS: ①With the decrease of G418 concentration, the cells in the untransfected and lipofectamine groups died, and stably EGFP expressed MSCs were obtained; after G418 screening, there was a cell clone undergone 35 passages and continued to proliferate, whose appearance and growth characteristics were similar to the untransfected MSCs observed under inverted microscope. ②The fifth passage pEGFP-C1-transfected hMSCs and tenth passage untransfected hMSCs remained telomerase-negative, but the K562 and fifth passage hTERT-transfected cells showed positive telomerase activity. ③The telomerase activity of the fifth and thirtieth passage hTERT-transfected cells was positive. ④The hTERT-MSCs at passage 10, 20 and 30 had 23 pairs of chromosomes, and two X chromosomes. So they were still normal diploid with normal chromosome appearance and number. ⑤Many hTERT-transfected MSCs had the typical appearance of neuron-like cells. RT-PCR analysis showed that th expressions of MAP2 and NF-M were increased.CONCLUSION:Ectopic expression of the hTERT gene is found in hMSCs,and can induce the telomerase activity of hMSCs.The ectopic expression of the hTERT gene in hMSCs could extend the life spans of cells and maintain their multipotent differentiation capacity.

[ABSTRACT]OBJECTIVETo investigate the prevalence of allergic rhinitis in Beijing primary and middle school students.METHODSStratified cluster sampling was conducted with the school as a unit. The investigated subjects included the 7 to 15 years old students from the primary and middle school in Beijing Dongcheng District and Changping District. The epidemiological investigation was carried out using the designed allergic rhinitis questionnaire. Allergen skin prick test was performed in students randomly selected from those who participated the questionnaire survey. The results were statistically analyzed.RESULTS1. The self-reported prevalence of allergic rhinitis was 49.68% in Beijing primary and middle school students. 2. Self-reported prevalence increased with age going up. 3. City center self-reported prevalence was higher than that in suburb areas. 4. The confirmed prevalence of allergic rhinitis in Beijing primary and middle school students was 21.09%, in which, the male prevalence rate was 24.83% and the female prevalence rate was 14.11%. 5. The 5.14% of the students with allergic rhinitis were combined with asthma.CONCLUSIONThe self-reported and confirmed prevalence of allergic rhinitis in Beijing primary and middle school students was 49.68% and 21.09% respectively.

Objective To evaluate the effect of internal iliac artery or abdominal aorta blockade on the pressure of internal iliac artery net in order to provide theoretical basis for reasonable option of arterial blockade in management of arterial bleeding of pelvic fractures.Methods Five goats were included in the study.The measurement of the pressure of internal iliac artery net was made in the following steps:( 1 ) measurement of the pressure of normal internal iliac artery,(2) measurenent of the pressure following blockade of unilateral internal iliac artery,(3) measurement of the pressure following blockade of bilateral internal iliac arteries,(4) measurement of the pressure following blockade of abdominal aorta and bilateral internal iliac arteries simultaneously,(5) measurement of the pressure following blockade of abdominal aorta only.Results The normal internal iliac artery pressure was ( 57.84 ± 13.46 ) mm Hg.The pressures following the blockade of unilateral internal iliac artery,bilateral internal iliac arteries,abdominal aorta and bilateral internal iliac arteries sinultaneously,and abdominal aorta only were (38.40±17.39) mm Hg,(29.70 ± 12.16) mmHg,(32.80 ± 17.02) mm Hg and (29.20 ± 18.52) mm Hg,respectively.All the blocking designs had obvious effect on the pressure of normal internal iliac artery ( P ＜ 0.05 ),while the various blockade modes themselves showed no statistical differences (P ＞ 0.05). Conclusion The upper described four modes of blockade are similar in decreasing the pressure of the internal iliac artery net.Thereby,only one of them is enough in management of artery hemorrhage following pelvic fractures.

Objective To evaluate the efficacy and toxicity of the docetaxel combined with nedaplatin or cisplatin in the treatment of patients with advanced head and neck carcinoma.Methods 58 patients with advanced head and neck carcinoma were enrolled into the study.These patients were divided into nedaplatin group (27 patients:docetaxel 75mg/m2 on day 1 and nedaplatin 80mg/m2 on day 1 of the 21-day cycle) and cisplantin group( 31 patients:docetaxel 75mg/m2 on day 1 and cisplatin 25mg/m2 on day 1-3 day of 21-day cycle).Each patient should complete two cycle.Results The response rate in nedaplatin group was 59.2％ and in cisplantin group was 54.8％,the difference was statistically significant between the two groups( P ＞ 0.05 ).The rate of white blood cell and plate let reduction in nedaplatin group was 55.5％,40.7％,respectively,and those in cisplantin group was 51.6％,35.4％,respectively,the difference was statistically significant between the two groups ( call P ＜ 0.05 ).The rate of vomit in nedaplatin group was 29.6％,which was lower than that of cisplantin group (64.5％) ( x2 =4.02,P ＜ 0.05 ).Conclusion In the treatment of advanced head and neck carcinoma,the combination of docetaxel and nedaplatin had the same efficacy as the combination of docetaxel and cisplatin,and they appeared to be more-tolerated.

[ABSTRACT]OBJECTIVETo investigate the species distribution of the common inhaled allergens among the primary and middle school students in Beijing.METHODSA total of 1280 students who were randomly selected underwent 20 kinds of common allergen skin prick test. Skin prick test were positive in 495 students.RESULTS49.3% of the Beijing primary and secondary school students were positive for more than four kinds of allergens. The dust mites and fall pollen allergens were positive at the same time in 37.4% of the allergen positive students. The commonest three allergens were D. farina, D. pteronginus and Large seed fleabane pollen in urban area, and were dermatophagoides farinae, willow tree pollen and Large seed fleabane pollen in suburban area. The positive rate of skin prick test decreased with age.CONCLUSIONThe dust mites and fall pollen are the most important allergens in primary and middle school students in Beijing.

Objective To evaluate the diagnostic value of endoscopic ultrasonography (EUS ) combined with detection of immunoglobulin (Ig ) and T‐cell receptor (TCR ) gene rearrangements in primary gastrointestinal lymphoma (PGIL) .Methods From 12nd January ,2012 to 23rd May ,2014 ,the clinical data of 24 patients with suspicious PGIL under endoscopy (regular biopsy negative and without treatment) and underwent further EUS examination was retrospectively analyzed .All patients received EUS‐guided biopsy or EUS‐guided fine needle aspiration (FNA) and the tissue specimens were detected for Ig and TCR gene rearrangements .Considering biopsy result ,surgical pathological diagnosis and follow‐up result as gold standard ,the clinical significance of sensitivity ,specificity ,positive predictive value (PPV) , negative predictive value (NPV ) and accuracy of EUS combined with Ig /TCR gene rearrangements in PGIL were explored .Results Among 24 patients ,19 patients were finally diagnosed as PGIL ,which were all non‐Hodgkin′s lymphoma (NHL ) ;monoclonal gene rearrangement was found in 13 cases of the 19 cases .The left five cases were not lymphoma lesions (three cases of gastritis ,one case of leather stomach and one case of malignant melanoma) with no monoclonal gene rearrangement .In cases diagnosed as PGIL , 14 were B cell NHL ,which included eight cases of muscosa‐associated lymphoid tissue (MALT) lymphoma and six cases of diffuse large B cell lymphoma .Of which ,immunoglobulin heavy chain (IgH)/immunoglobulin kappa (IgK) gene rearrangement was found in 11 cases .A total of five cases were T cell NHL including one case of anaplastic large cell lymphoma , one case of NK /T cell lymphoma and three cases of enteropathy‐associated T‐cell lymphomas . TCR gene rearrangement was found in two cases .Because theoretically ,there was no gene rearrangement in natural killer (NK )/T cell lymphoma ,so NK /T cell lymphoma was excluded from statistical analysis .The sensitivity ,specificity ,PPV ,NPV and accuracy of EUS combined with Ig /TCR gene rearrangements detection in PGIL were 72 .2% ,100 .0% ,100 .0% , 50 .0% and 78 .3% ,respectively .Conclusion The detection of monoclonal gene rearrangement in tissues from EUS‐guided biopsy or EUS‐guided FNA had better diagnostic value in PGIL ,which improved the objectivity and accuracy of lymphoma diagnosis .