By non-steady method,the effective diffusivity of ferrous sulphate within alginate calcium gel entrapped without bacteria was measured.Meanwhile the oxidation ability of entrapped bacteria was analyzed.Experimental results showed that the effective diffusion coefficient of ferrous sulphate decreased with the increase of alginate concentration,the optimum alginate concentration is 2%(W/V).The effect of calcium chloride on the effective diffusivity was neglectable.The incubation of ferrooxidans would pass through 10 hours,and the diffusion coefficient within gel entrapped Thiobacillus ferrooxidans cells was less remarkably than that of ferrous sulphate without entrapped cells.For the entrapped cells,the absolute oxidation time was shortest and the rate change was fastest with the initial Fe concentration 5g/L.The absolute oxidation time was same when the initial Fe concentration was 8g/L and 10g/L.

Anastomosis, Surgical ; Colon, Sigmoid/surgery* ; Colorectal Neoplasms/surgery* ; Humans ; Robotics

PURPOSEThis study aims to explore the biomechanical mechanism of lower limb injuries to the driver by establishing a finite element (FE) simulation model of collisions.

METHODSFirst a minibus FE model was integrated with a seat belt system. Then it was used to rebuild two collisions together with the total human model for safety (THUMS) provided by Toyota Motor Corporation: a rear-end collision between a minibus and a truck and a head-on collision of a minibus to a rigid wall. The impact velocities of both collisions were set at 56 km/h. The vehicle dynamic response, vehicle deceleration, and dashboard intrusion in the two collisions were compared.

RESULTSIn the minibus rear-end truck collision, the peak values of the von Mises equivalent stress at the tibia and the femur were 133 MPa and 126 MPa respectively; while in the minibus head-on rigid wall collision, the data were 139 MPa and 99 MPa. Compared with the minibus head-on rigid wall collision, the vehicle deceleration was smaller and the dashboard intrusion was larger in the minibus rear-end truck collision.

CONCLUSIONThe results illustrate that a longer dashboard incursion distance corresponds to a higher von Mises equivalent stress at the femur. The simulation results are consistent with the driver's autopsy report on lower limbs injuries. These findings verify that FE simulation method is reliable and useful to analyze the mechanisms of lower limb injuries to the driver in minibus frontal collisions.

Accidents, Traffic ; Automobile Driving ; Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Lower Extremity ; injuries

OBJECTIVETo study the epidemiologic characteristics of hand-foot-mouth disease (HFMD) in Guiyang between 2008 and 2010.

METHODSThe epidemiologic characteristics of HFMD were analyzed by descriptive statistical methods based on the data from the China Information System for Disease Control and Prevention.

RESULTSA total of 27383 cases of HFMD were recorded in Guiyang between 2008 and 2010. The incidence of HFMD increased from 66.4439/100000 in 2008 to 163.9276/100000 in 2009 and 471.5515/100000 in 2010 (P<0.01). The mortality rate was 0.1026/100000 in 2010, which was significantly lower than in 2009 (0.2821/100000) (P<0.05). HFMD occurrence showed seasonality and reached a peak between April and June. HFMD cases were commonly noted in children under 5 years old, and especially in children under 3 years old. The main detected pathogen was human enterovirus 71 (EV17) in 2009. Whereas in 2010 the disease was mainly caused by CoxA16 and other intestinal viruses.

CONCLUSIONSThe incidence of HFMD in Guiyang increased year by year from 2008 to 2010, but the mortality rate decreased year by year. HFMD occurrence showed an obvious seasonality. HFMD was common in children under the age of five. The main pathogens of this disease included EV17, CoxA16 and other intestinal viruses.

Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; China ; epidemiology ; Enterovirus A, Human ; isolation & purification ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Infant ; Middle Aged ; Time Factors

OBJECTIVETo establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen.

METHODSPrimary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination.

RESULTSThe morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor, hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-alpha (tumor necrosis factor-alpha), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found.

CONCLUSIONEctopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.

Antigens, Polyomavirus Transforming ; genetics ; metabolism ; Cell Culture Techniques ; methods ; Cell Size ; Cell Survival ; physiology ; Cells, Cultured ; DNA-Binding Proteins ; genetics ; metabolism ; Endothelial Cells ; cytology ; physiology ; Genetic Enhancement ; methods ; Humans ; Protein Engineering ; methods ; Recombinant Proteins ; metabolism ; Telomerase ; genetics ; metabolism ; Tissue Engineering ; methods ; Transfection ; methods ; Umbilical Veins ; cytology ; physiology

OBJECTIVETo investigate the relationship between SNPs reported in previous studies and the blood lipid level in the Tibetan population.

METHODSRandom cluster sampling was employed in 5 areas (Lhasa, Shigatse, Shannan, Nagqu, and Nyingchi). The levels of cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) from blood samples were determined and DNA was extracted for genotyping and statistical analyses.

RESULTSAmong 1 318 subjects aged >18 years enrolled in this study, 367 had dyslipidemia with a prevalence of 27.8%, of whom dyslipidemia males accounted for 33.1% and dyslipidemia females -24.5%. Results of the correlation analysis between all SNPs and TG showed that the SNPs of rs714052 and rs964184 were related to the serum TG level. Subjects with rs714052 CC genotype had the lowest TG level, and the highest TG level was found in those with rs714052 TT genotype. The serum TG level in individuals with TC genotype lied in between the above two population groups. Subjects with rs964184 CC genotype had the lowest TG level, and the highest serum TG level was noted in those with rs964184 GG genotype.

CONCLUSIONSeveral SNPs were found to be related to the serum TG level in the Tibetan population. The APOA5 gene and MLXIPL gene may be closely associated with the serum TG level in this ethnic population group.

Dyslipidemias ; epidemiology ; genetics ; Female ; Genotype ; Humans ; Lipids ; blood ; Male ; Polymorphism, Single Nucleotide ; Tibet ; epidemiology

OBJECTIVETo immortalize human umbilical vein endothelial cells (HUVECs) by ectopic expression of the telomerase reverse transcriptase enzyme (hTERT), and by Simian Virus 40 Large T (SV40LT) antigen without malignant transformation.

METHODSTwo different retroviruses that contained hTERT/SV40LT cDNA fragment and drug resistance gene were constructed, and were used to transfect normal primary HUVECs. The transfected cells were screened with 500 microg/ml G418 and 4 microg/ml puromycin. Drug resistance cell clones were selected 3 days after transfection and cultured for further studies. An under inverted microscope and a scanning electron microscope were used to observe the morphology and growth of the cells. The expression of VIII factor and transfected DNA fragments were detected for identification of the endothelial origin and successful transfection. And the expression of E-selectin and endothelial lipase with or without the stimulus of TNF-alpha were also assayed to analyze the biological activity of the transfected cells.

RESULTSThe cells were homogenous, closely apposed, large, flat, and polygonal, displayed a characteristic ovoid nucleus with one or two nucleoli and formed monolayer with polygonal shape without overlapping. Immunocytochemical staining showed the existence of VIII factor. SV40LT/hTERT antigen expressed by the transfected cells was detected, while the contrasts had non-expression. Telomerase activity of the cell was detected in the transfected cells, which was 0.36 at 12 th passage and 0.38 at 50 th passage. However, the activity in the normal HUVECs was 1.12 at the first passage and 0.06 at the third passage assayed by PCR-ELISA. Both E-selectin and endothelial lipase were all specific in endothelial cells. The expressions of these two were also detected. And the expression of E-selectin can be up-regulated with the stimulus of TNF-alpha, while the expression of endothelial lipase was not unregulated significantly.

CONCLUSIONEctopic expression of hTERT and SV40LT can effectively immortalize HUVECs without tumorigenesis.

Antigens, Polyomavirus Transforming ; genetics ; Cell Line, Transformed ; Endothelial Cells ; cytology ; metabolism ; Humans ; Simian virus 40 ; immunology ; Telomerase ; genetics ; Transfection ; Umbilical Veins ; cytology

OBJECTIVETo investigate the regulatory effect of potassium channel blocker (tetraethylammonium [TEA], aminopyridine [4-AP], glibenclamide [Glib]) on the proliferation of SD rat prostatic epithelial cells in vitro.

METHODSThe primary culture was prepared by collagenase dissociation of minced prostatic tissues. Cells were cultured in serum-free prostate epithelial cell growth media and identified by immunocytochemical studies. TEA and 4-AP at the concentration of 1, 5 and 10 mmol/L and Glib at the concentration of 10, 50 and 100 mol/L were added, and after 24, 48 and 72 hours of culturing, a cell column diagram was drawn and the cell number counted. The post-passage cell growth was observed by MTT assay and Hoechst33258 nucleus staining.

RESULTSThe cultured cells showed the typical morphological features of epithelia, with positive stain. MTT assay and Hoechst33258 staining showed that TEA, 4-AP and Glib at the increasing concentration effected different degrees of proliferation of prostatic epithelial cells after 24, 48 and 72 h (P < 0.01).

CONCLUSIONThe potassium channel blocker is a direct physiological regulator of the proliferation of SD rat prostatic epithelial cells.

Animals ; Cell Proliferation ; drug effects ; Cells, Cultured ; Epithelial Cells ; drug effects ; Male ; Potassium Channel Blockers ; pharmacology ; Prostate ; cytology ; drug effects ; Rats ; Rats, Sprague-Dawley

Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen. Methods:Primary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination.Results: The morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor,hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-α (tumor necrosis factor-α), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found. Conclusion: Ectopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.

Objective: To establish an echocardiography parameter scoring system for assessing the risk of 1 year re-admission in patients with left ventricular systolic dysfunction (LVSD). Methods: A total of 412 chronic LVSD patients treated in our hospital from 2007-01 to 2016-01 were studied and the end point event was 1 year re-admission. The data included in 280 patients from 2007-01 to 2014-12 for establishing the scoring system and 132 patients from 2015-01 to 2016-01 for verifying the system. Based on 7 echocardiography parameters, the patients were divided into 7 sets of groups: ① Left ventricular diameter (LVD): Group0, n=290 and Group1, n=122;② Mitrial regurgitation (MR): Group0, n=203, Group1, n=138 and Group2, n=71; ③ Tricuspid regurgitation (TR): Group0, n=302, Group1, n=90 and Group2, n=20; ④ LVEF: Group0, n=272 and Group1, n=140; ⑤ Pulmonary artery systolic pressure: Group0, n=282 and Group1, n=130; ⑥ Hydropericardium: Group0, n=347 and Group1, n=65; ⑦ Hydrothorax:Group 0, n=261, Group1, n=86 and Group2, n=65. The parameters were identified by COX regression analysis, weighted value of scoring system was calculate by hazard ratio (HR), predictive value for1 year re-admission was assess by ROC curve and finally, scoring integration was verified by validation data group. Results: The integration score was calculated as follows: LVD>60mm=1 point; TR: Group1=1 point and Group2=3 points; MR: Group1=2 points and Group2=4 points; Hydrothorax: Group1=2 points and Group2=3 points;Hydropericardium=1 point. COX regression analysis indicated that for 1 year re-admission: HR=1.552 in Group1 vs Group0, HR=3.374 in Group2 vs Group0 and HR=4.562 in Group3 vs Group0, all P<0.05. The AUC of ROC for establishing the data was 70.0% (95% CI 0.640-0.761) and for verifying the data was 70.4% (95% CI 0.616-0.792); the best integration score was 4 points. Conclusion: Echocardiography parameter scoring system may better predict the risk of 1 year re-admission in LVSD patients which is superior to single echocardiography parameter.