Objective To assess the effect of smoking and body mass index(BMI) on lung cancer incidence density in male workers.Methods Risk factors of cardiovascular diseases in baseline were surveyed in 1974,1979 and 1980 for 5 137 men aged more than 18 years old from Beijing Capital Steel and Iron Company.Follow-up was carried out to 2001;all diseases were identified by uniform standard.Cox proportional hazards model was used to analyze the relationship between smoking,BMI and lung cancer.Results During mean follow-ups of 20.8 years,106 cases of lung cancer occurred.The crude incident rates of lung cancer were 102.2 cases per 100 000 person-years.After adjustment for age,BMI and other established risk factors,cigarettes consumption of greater than 20 cigarettes/day versus no smoking was associated with a relative risk of lung cancer of 3.45(95% confidence interval(CI): 1.58～7.53).In categories of BMI of less than 18.5(underweight),18.5～24.9(normal weight) and more than 25 kg/m2(overweight and obesity),adjusting for age and other covariables,all workers and smoking workers both showed decreasing tendencies in relative risks of lung cancer in higher BMI groups.The pattern was similar after excluding the early 5-year lung cancer patients.Grouping in smoking and BMI levels,compared with underweight smokers,the relative risks for lung cancer of normal-weight nonsmokers and nonsmokers with overweight and obesity,as well as smokers with overweight and obesity were 0.25(95% CI: 0.08～0.84),0.16(95% CI: 0.04～0.74) and 0.23(95% CI: 0.07～0.77),respectively.Smokers with underweight had higher risk for lung cancer.Conclusion Smoking and underweight increased the risk of lung cancer.Keeping normal weight and giving up tobacco were important for the prevention of lung cancer.

BACKGROUND:Rapid development of spermatogonial stem cells is the new hope for assisting reproductive technologies,and the stability of the number and structure of the chromosome cultured in vitro is one of the important factors in usage.OBJECTIVE: To study the influential factors on G-band exhibition in mouse spermatogonial stem cells, so as to offer a technology to identify karyotype of stem cells in culture.DESIGN: Observational experiment.SETTING: Luzhou Medical College.MATERIALS: The experiment was conducted in the Laboratory of Medical Molecular Biology, Luzhou Medical College from March 2004 to April 2005. 10 days old male and female Kunming mice were provided by Department of Animal of Luzhou Medical College (number of license No. 17 of experimental animal quality administration in Sichuan province).There were low-sugar DMEM medium, 10 mg/L Mitomycin-C, IMDM medium, 1 ×10-5 mol/L colchicines (PBS allocation),7.5 mmol/L KCL, fixative (mixture glacial acetic acid with methanol in 1:3), Giemsa staining solution and 0.25% zymine.METHODS: Bone marrow was aspirated from the thigh bone of mouse for feeder layer cells preparation. Cells from the male mice testis of 7-8 days after birth were prepared and made into cell suspension. After adjusting the cell density to 3×105 L-1, they were inoculated into the feeder layer of bone marrow stromal cells. Cells were cultured at 37 ℃ in CO2 incubator containing CO2 of 0.05 volume fraction and 70% humidity. The proliferation groups of stem cells cultured 15-20 days were selected, stirred and spread, and then treated with colchicine for 4-6 hours. Cell suspension was collected,and then stained after hypotonic treatment. The cells whose chromosomes were dispersed well and in metaphase were selected, and number of chromosomes was counted, and then the morphology of chromosomes was observed.MAIN OUTCOME MEASURES: Culture of bone marrow stromal cells and spermatogonial stem cells and coloration and count of chromosomes.RESULTS: The karyotype of spermatogonial stem cells was the same as the body cells of normal mouse, which showed granule or rod-shape. Karyotype was 20 pairs, 40 bars. Three kinds of chromosome morphology could be observed under oil immersion lens. The first type was condensed, which could be counted in total, but the band could not be seen.The second type was chromatosome that spread completely in the center of equatorial plate and were in metaphase. In this phase, total numbers and band were seen clearly. Last type-chromosomes had already folded and moved towards two poles and concentrated gradually, the total number of chromosomes could be counted, but bending could not be seen clearly.CONCLUSION:Many factors can affect the karyotype of spermatogonial stem cells, including the phase of cell division,effect of hypotonic solution, diffusion of the cell when dropping slides, concentration of trypsin and digestion time, etc.

Objective To determine the effectivity of 5-azacytidine(5-Aza) inducing the cardiomyogenic SCs were isolated and purified from Sprague-Dawley (SD) rats. Some BMSCs were induced with 5-Aza,group Ⅰ was not induced with 5-Aza and the third generation of cells were used for the next experiment; group Ⅱ were cultured and induced with 5-Aza( 10 μmol/L) at the third day of the culture for 24 h; group Ⅲ were induced with 5-Aza( 10 μmol/L) for 24 h when the third generation of cell were fused; group Ⅳ were induced with 5-Aza( 10 μmol/L) for 24h at the third day of primary cuhure,which were induced with 5-Aza( 10 μmol/L) for 24 h before the third gener-phosis was found in the BMSCs among groups. CD34 was negatively expressed and CD29 and CD44 were positively gle 5-Aza inducing group(group Ⅲ ) was much higher than that in no 5-Aza inducing group( group Ⅰ ) [ MHC : (6. 82±2.05 ) % vs (3.61±1.14) % ], cTnI: (5.63±1.86) % vs (2.76±0.82) %, P < 0.05 ], but was significantly lower than the percentage in the double 5-Aza inducing group ( group Ⅳ ) [ MHC : ( 12.18±3.16) % vs ( 6.82±2. 05)% ] ,cTni:(9.93±2.79)% vs(5.63±1.86)% ,P<0.05]. Conclusions 5-Aza could promote the cardio-myogenic differentiation of BMSCs in a "Cardiac-like" Milieu. 5-Aza double induing is better than the single indu-cing.

Ras is best known for its ability to regulate cell growth, proliferation and differentiation. Mutations in Ras are associated with the abnormal cell proliferation which can result in incidence of all human cancers. Extracellular signal-regulated kinase (ERK) is a downstream effector of Ras and plays important roles in prognosis of tumors. Recently, evidence has gradually accumulated to demonstrate that there are other effectors between Ras and ERK, these proteins interact each other and constitute the thorough Ras/Raf/MEK/ERK signaling pathway. The pathway has profound effects on incidence of esophageal carcinoma and clinical applications of some chemotherapeutic drugs targeting the pathway. Further understanding of the relevant molecular mechanisms of Ras/Raf/MEK/ERK signaling pathway can be helpful for the development of efficient targeting therapeutic approaches which contribute to the treatment of esophageal cancer. In this article, roles of Ras/Raf/MEK/ERK signaling pathway in esophageal carcinoma as well as pharmacological targeting point in the pathway are reviewed.

Objective To establish the A549 cell line with stable expression of HIF1α by using lentiviral vector system.Methods Primers were designed and synthesized with human HIF1α gene coding sequence by the National Center of Biotechnogical Information(NCBI) as the template.HIF1α was amplified by PCR.The HIF1α fragment recycled by enzyme digestion was recombined with prepared lentiviral vector HBLV-RFP-Puro.The recombinant plasmid was identified by PCR and gene sequencing.The recombinant plasmid and the auxiliary plasmid were co-transfect into 293T cell.After filtration and concentration of packaged virus,the viral titer was detected by using the dilution counting method.The prepared lentivirus was infected A549 cells.The drug screening was adopted to stabilize the transfected cell line.The transfection effect was detected and observed by fluorescence microscope and Western blotting.Results The HIF1α fragment amplified by PCR was successfully verified and the recombinant plasmid was successfully constructed by PCR and gene sequencing identification.High-titer LV-HIF1α was obtained by successful package.After LV-HIF1α infecting A549 cells,the cells showed the red fluorescence by fluorescence microscope.The expression level of HIF1α in the LV-HIF1α group was significant higher than that in the control group by Western blot.Conclusion The 549 cell line with HIF1α stable expression mediated by lentivirus is constructed successfully.

Objective To investigate the methylation situation of let‐7a‐3 promoter in patients with chronic myeloid leukemia (CML) and its clinical significance .Methods The methylation level of let‐7a‐3 promoter in the bone marrow mononuclear cells of 52 CML patients and 25 controls was detected by using the real‐time quantitative methylation‐specific PCR (RQ‐PCR) .Results The non-hypomethylation of let‐7a‐3 promoter was positive in 31 cases(59 .6% ) of 52 CML patients ,while only 1 case(4% ,1/25) in the control group ,the difference between the two groups were statistically significant (P< 0 .01) .The ROC curve analysis showed that the non -hypomethylation of let‐7a‐3 has better specificity for the auxiliary diagnosis of CML .The significantly posi‐tive correlation was found between the non -methylation level of let‐7a‐3 promoter and the BCR/ABL transcription level (r=0 .641 ,P=0 .001) .In contrast ,there was no obvious correlation between the non -methylation level of let‐7a‐3 promoter and the WBC count ,platelet count and hemoglobin levels(P>0 .05) .The non-hypomethylation level of let‐7a‐3 in chronic phase and accel‐erate phase was significantly higher than that in blastic crisis of CML .Conclusion The hypomethylation level of let‐7a‐3 promoter is decreased with disease progression .

Objective To promote comprehension of pulmonary sequestration by investigating the diagnosis and surgical treatment methods of this disease.Methods A retrospective analysis of the clinical records of 27 patients with pulmonary sequestration was made,15 male patients and 12 female patients,with the age ranging from 4 to 56 years old.The patients were examined by chest radiography,computerized tomography (CT),computerized tomography angiography (CTA),magnetic resonance imaging (MRI) before the surgery.Eleven patients were confirmed preoperatively as pulmonary sequestration by the contrast enhanced CT and 64slice spiral CT examinations.Sequestrectomy was performed on patients with extralobar sequest ration (ELS) and lobectomy was performed on patients with intralobar sequestration (ILS).There were 21 cases of left lower lobectomy,5 cases of right lowerlobectomy,and 1 case of right sequestrectomy.Results All recovered uneventfully.No significant complications occurred in the perioperative period.All patients were cured and discharged from hospital.No relapse was reported during follow up period.Conclusion Diagnosis mainly depended on the chest radiography,CT,MRI and CTA.Surgical operation should be the best choice of treatment.

Three cases of terminal stage heart disease received orthotopic heart transplantation at the Department of Cardiothoracic Surgery, the First Hospital of Nanchang University between August 2001 and December 2003. These three cases were all female and died of brain death. Body weight difference between donor and recipient was less than 20%. All three cases underwent superior and inferior vena cave osculation and received immunosuppressive therapy of cyclosporine A, prednisone, and mycophenolate postoperatively. They were successfully discarded. Heart function recovered to grade Ⅰ-Ⅱ(NYHA). No infection or serious rejection was found during the surgery. These results indicate that good donor heart preservation, consummate perioperative processing, and proper immunosuppressiva therapy are the key measures of successful heart transplantation.

Objective To examine the relationship between alcohol consumption and the incidence of metabolic syndrome (MS) in Chinese adults.Methods A total of 27020 Chinese adults aged 35 to 74years were enrolled in this prospective cohort study.Frequency or type of alcohol consunption was assessed in 1998 and 2000.Follow-up study on MS was conducted during 2007 and 2008.Results Over an average 8years' follow-up,2362 MS patients were identified among 14 572 individuals who did not have MS at baseline.After adjustment for age,location,education level,physical activity,cigarette smoking,body mass index and the number of MS components,compared with non-drinkers,relative risk ( RR ( 95％ confidence interval (CI))) and the Population Attributable Risk Percent (PARP) of MS of male drinkers was 1.24( 1.06 to 1.45 ) and 10.13％,respectively.RR (95 ％ CI) of MS was 1.36 ( 1.02 to 1.82 ),1.34 ( 1.03 to 1.74) and 1.41 (1.13 to 1.77) for male drinkers consuming alcohol 10.1 -20 g/d,20.1 -40 g/d,and ＞40 g/d.RR(95％ CI) of MS was 1.25 ( 1.01 to 1.55) for males drinking 2 -5 times/week and 1.26(1.04 to 1.52) for males drinking ≥6 times/week.RR (95％ CI) of MS was 1.60 ( 1.05 to 2.45),1.30(1.02 to 1.65) and 1.27 (1.06 to 1.52) for beer,liquor and the beer + liquor male consumers.The corresponding RR(95％ CI) was 2.67(1.26 to 5.65) and 3.38 (1.35 to 4.22) for female drinkers consuming alcohol 10.1 -20 g/d and ＞20 g/d.Conclusions Drinking alcohol more than 10 g/d may be associated with an increasing risk of MS,especially for women.Drinking more than twice per week,beer and/or liquor consumption can significantly increase the risk of MS in men.

Objective To explore the clinical application of subxyphoid approach thoracoscopic surgery in thymoma resection. Methods The clinical data of 15 cases of mediastinal tumors receiving subxyphoid approach video-assisted thoracoscopic surgery from June 2015 to May 2017 were analyzed retrospectively.Among these cases,there were 6 male cases and 9 female cases, and the average age was(48.5 ±5.4)years old.There were 6 cases of thymoma with myasthenia gravis,including 5 cases of ocular myasthenia gravis and 1 case of mild systemic myasthenia gravis. Results All the 15 cases of operations were performed successfully without conversion to open surgery.The average operation time was(95 ±15)min, and average bleeding was(50 ±10)ml.The average hospital time was(4.2 ±1.5)days, and average thoracic cavity drainage time was(1.5 ±1.0)days.No postoperative complications occurred.Pathological reports showed that type A thymoma in 8 cases,type AB thymoma in 5 cases,type B1 thymoma in 1 case,and type B2 thymoma in 1 case.The mean follow-up time of all the 15 cases was(6.5 ±2.5)months, and no thymoma recurrence was seen.According to the Monden standard,muscle weakness symptoms disappeared in 5 cases and improved in 1 case in the 6 cases with myasthenia gravis. Conclusion Subxyphoid approach thoracoscopic thymoma resection is safe and feasible.