Background and objectives To investigate the effect of hepatocyte growth factor (HGF) on left ventricular (LV) remodeling after acute myocardial infarction (AMI). Methods AMI was produced by ligation of proximal left anterior descending coronary artery(LAD) in 12 mongrel canines. These animals were randomized into 2 groups. In HGF group (n=6), canines were injected with pcDNA3-HGF lml (about 300ug) at the margin of infarcted myocardium; in control group (n=6) canines were injected with equal volume of normal saline. Cardiac function and left ventricular remodeling were evaluated with echocardiography at 1, 4, 8 weeks after MI. LV myocardium specimens were obtained at 8 weeks and stained with hematoxylin and eosin for histological examination or with sirius red to assess the collagen content. Results Compared with control group, LVEF in HGF group was significantly higher at 4 weeks (49.61+6.66 vs 39.84+6.39; P＜0.05) and at 8 weeks (51.57+8.53 vs 40.61+7.67; P＜0.05) after AMI, while LVESV was significantly lower in HGF group than that in control group at 8 weeks after AMI (18.98+3.47 vs 25.66+5.86; P＜0.05). Posterior left ventricular wall thickness decreased significantly from 1 wk to 8 wks after AMI in control group, while remained unchanged in HGF group. Compared with control group, histological examination showed more neovascularization and less scar, and sirius red staining indicated higher volume of type Ⅲ collagen (7.10±4.06% vs 3.77±1.09%; P＜0.05) and lower collagen Ⅰ/Ⅲ ratio value (1.11±0.52 vs 2.94±2.48; P＜0.05)in HGF group. Conclusion HGF gene transfer might improve cardiac function and LV remodeling after acute myocardial infarction by stimulating angiogenesis, reducing fibrosis, and reducing myocardial scarring.

The practical teaching system for information management and information system science in higher medical institutions was constructed with job skill training as its target by intruding the concept of competence-based education model into it in order to improve the practical performance of undergraduates majoring in informa-tion management and information system science. The system was designed by taking into consideration the teaching contents, teaching methods and teaching practice, and implemented in the undergraduates of Chengdu Medical College, and the implementation experiences were summarized.

BACKGROUND:A number of studies have shown that bone marrow mesenchymal stem cells can survive in the infarcted myocardium and improve cardiac function. OBJECTIVE:To investigate the effects of al ogeneic rat bone marrow mesenchymal stem cells on heart failure in acute myocardial infarction models of rats and possible mechanisms. METHODS:Rat bone marrow mesenchymal stem cells were isolated from the bone marrow of 39 male Wistar rats by density gradient centrifugation with Percol . After ligating anterior descending coronary artery, 39 female Wistar rats were randomly divided into three groups:control group (Dulbecco’s modified Eagle’s medium, n=12), mesenchyma stem cells group (n=15) and mononuclear cells group (n=12). Eight weeks later, hemodynamics and left ventricular function were measured. Histopathological and immunohistochemical examinations were performed. RESULTS AND CONCLUSION:Compared with the control group, left ventricular end diastolic pressure, left ventricular relative weight, the col agen volume fraction of type I and type III in the infarction zone of the left ventricle were al significantly decreased, in contrast to ±dp/dtmax,-dp/dtmax/left ventricular systolic pressure, body weight and vascular density in infarction zone were al significantly increased both in mesenchymal stem cells group and mononuclear cells group. There were no significant differences between two treatment groups except for interventricular septal thickness and vascular density in non-infarction zone. 5-Bromo-2'-deoxyuridine positive cells were observed in the infarction area of mesenchyma stem cells group but no positive cells in mononuclear cells group. Some bal-like cellmasses were found positively stained with desmin and cardiac troponin T. Results have suggested that embedded bone marrow mesenchymal stem cells survived in exogenous host hearts. The therapy of mononuclear cells and mesenchymal stem cells could limit the left ventricular remodeling after acute myocardial infarction and improve left ventricular function through angiogenesis inducing and col agen deposition decreasing.

Objective To investigate the effect of hepatocyte growth factor (HGF) on mitral regurgitation caused by acute myocardial infarction in canines.Methods The acute myocardial infarction model was established by ligating proximal left anterior descending coronary artery (LAD) with 13 hybrid canines. The myocardial infarction model was successfuly established in 12 animals and those were randomly divided into the HGF-group and control group with 6 animals in each group. Canines of the HGF-group were injected with pc-DNA3-HGF 1 ml (about 300 μg) at the margin of infarcted myocardial and animals of the control group were injected with equal volume saline. The data were measured through echocardiography in the 1st, 4th and 8th week after ligation as following parameters: left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV), left atrial area, mitral regurgitation area and the ratio of left atrial area to mitral regurgitation area. Left ventricular myocardium specimens were obtained in the 8th week after ligation and stained with hematoxylin and eosin for histological examination or with picrosirius red staining to assess the collagen content.Results Compared with the control group, LVEF in the HGF-group increased in the 4th week after ligation; LVEF significantly improved and LVESV decreased in the 8th week after ligation ( P<0.05). In the 8th week after ligation, left atrial area, mitral regurgitation area and the ratio of left atrial area to mitral regurgitation area in the HGF-group were lower than that in the control group. In the HGF-group, neovascularization and fewer scars were observed histologically. Compared with the control group, the HGF-group showed higher capillary density in margin of infarcted area by factor Ⅷ-related immunohistochemistry staining ( P<0.01).Conclusion HGF gene can improve cardiac function and relieve mitral regurgitation after acute myocardial infarction by stimulating angiogenesis, reducing fibrosis, diminishing myocardiolysis and scarring.

BACKGROUND: To repair bone defect, histocompatibility, growing characteristics, biodegradation and repairing mechanism of nanometer need to be further studied in clinic. OBJECTIVE: To observe the growing characteristics and histocompatibility of nano-hydroxyapatite (Nano-HA) for repairing jaw defect of rabbits.DESIGN: Randomized grouping animal study.SETTING: Beijing Jishuitan Hospital and Stomatology College of Jiamusi University.MATERIALS: A total of 24 New Zealand rabbits, either gender, weighing 2.5-3.5 kg, were provided by Animal Experimental Center of Jiamusi University. The animal experiment had got confirmed consent from local ethic committee. Nano-HA was provided by Material Engineering College of Jiamusi University and dealt with routine hyperthermia/hypertension sterilization. In addition, hydroxyapatite was provided by Wuhan Industry University, and the diameter was 1.0-2.0 μm.METHODS: The experiment was carried out in the Experimental Animal Center of Jiamusi University from November 2001 to May 2006. All rabbits were randomly divided into experimental group and control group with 12 in each group. Bone defect in the diameter of 1.0 cm was produced on body of mandible. Nano-HA was used to repair the bone defect of rabbits in the experimental group, while hydroxyapatite was used to repair the bone defect of rabbits in the control group. At 1, 4, 8 and 12 weeks after operation, all rabbits were sacrificed. In addition, medical imaging analysis system was used to analyze generative quantity of tissue in the two groups; meanwhile, histological quality and quantity were also analyzed so as to observe histocompatibility and newborn osteogenesis. MAIN OUTCOME MEASURES: Histocompatibility and newborn osteogenesis.RESULTS: With the time passing by, the amount of repairing materials was decreased because of the combination with newborn tissue into bone in bone defect-repaired region in the experimental group. When it was closed to normal bone, the amount was stable. However, bony callus was not able to grow in materials in the control group. Results of correlation analysis demonstrated that materials were negatively straight-line correlation with newborn bone (r = -0.912 0, P < 0.01). During the repairing procedure of bone defect, newborn bone was closely correlative with Nano-HA; while, with the increase of newborn bone, the amount of repairing materials was decreased because of the combination with newborn tissue into bone.CONCLUSION: Nano-HA can combine with newborn bone tissue so as to rapidly generate bone, while it has an excellent biocompatibility.

Objective To investigate the reasons of artifacts in 64-slice spiral CT coronary angiography.Methods One hundred patients with diagnosed or suspected coronary artery disease underwent retrospectively ECG-gated 64-slice spiral CT coronary angiogruphy.Maximum intensity projection(MIP),muhiplanar reformation(MPR)and volume rendering technique(VRT)were reconstructed.The reasons of artifacts were assessed by two experienced radiologists.Results A total of 1347 segments(1347/1500,89.8%)were reviewed,the artifacts were found in 192 segments(14.2%).Breath movement was the moat common artifact(124/192).and the other reasons included fast rate and irregular rhythm of the heart beat (42/192).while the phase mismatch was the third reason(22/192).Conclusions The common artifacts of 64-slice spiral CT coronary angiography includes breath movement,fast rate and irregular rhythm of heart beat and phage mismatch.Breath-holding control,low rate and regular rhythm of heart beat,muhiphage reconstruction are suggested for the accurate diagnosis.

Objective To investigate the effects of internal and external biliary drainage on liver regeneration of the obstructive jaundice rats after partial hepatectomy.Methods The rat models of obstructive jaundice with 70％ liver resection were successfully constructed.All the 120 rats were randomly divided into the control group:rats received middle and left hepatic lobectomy; internal drainage group:a drainage tube was placed between the dilated bile duct and the duodenum; external drainage group:a drainage tube was placed in the dilated bile duct.There were 40 rats in each group.Rats in the internal and external drainage groups received middle and left hepatic lobectomy at postoperative day 7.The blood and hepatic tissues were collected at postoperative day 0,1,2,4,12,24,48,72 hours after operation,and the rate of liver regeneration and mitotic index were determined.The expression of proliferating cell nuclear antigen (PCNA) and signal transducer and activator of transcription 3 (STAT3) in the hepatic tissues were detected by immunohistochemistry,and the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were detected by ELISA,and the mRNA expressions of TNF-α and IL-6 were detected by RT-PCR.All data were analyzed using the one way analysis of variance or SNK test.Results Within 72 hours after partial hepatectomy,the rate of liver regeneration of the internal drainage group was 94.86％± 12.72％,which was significant higher than 62.39％±8.01％ of the external drainage group and 45.77％ ± 5.41％ of the control group (F =33.62,P ＜ 0.05).The mitotoic index and PCNA levels of the 3 groups had obvious increase at postoperative hour 12,and the mitotoic index and PCNA levels of the external drainage group reached peak at postoperative hour 24,which were 24.47％ ± 4.01％ and 88.1％ ± 9.2％,respectively,the mitotoic index and PCNA levels of the control group and the external drainage group reached peak at postoperative hour 48,which were 15.80％ ± 1.08％,58.3％ ± 5.8％ and 18.40％ ± 1.12％,70.2％ ± 6.9％,respectively.The mitotoic index and PCNA levels of the internal drainage group were significantly higher than those of the control group and the external drainage group (P ＜ 0.05).The expression of STAT3 expression of the internal drainage group reached peak at postoperative hour 4,which was 42.6％ ± 3.6％ ;the expression of STAT3 expression of the control group and the external drainage group reached peak at postoperative hour 12,which were 22.9％ ± 2.0％ and 29.2％± 3.7％.The peak level of STAT3 of the internal drainage group was significantly higher than those of the control group and the external drainage group (P ＜0.05).The levels of TNF-α and IL-6 of the internal drainage group reached peak at postoperative hour 12,which were (227 ±23)U/L and (256 ± 32)U/L; the levels of TNF-α and IL-6 of the control group and the external drainage group reached peak at postoperative hour 24,which were (309 ± 41) U/L and (388 ± 40) U/L,(287 ± 30)U/L and (346± 33)U/L,respectively.The levels of TNF-α and IL-6 of the internal drainage group at postoperative hour 0,1,2,4,12,24,48,72 were significantly lower than those of the control group and the external drainage group (P ＜ 0.05).The expressions of TNF-α mRNA of the control group,internal drainage group and external drainage group reached peak at postoperative hour 4,which were 0.92 ±0.14,0.39 ±0.05,0.80 ±0.15,respectively.The expressions of IL-6 mRNA reached peak at postoperative hour 12,which were 0.79 ± 0.07,0.38 ± 0.06,0.63 ±0.10,respectively.The expressions of TNF-α mRNA and IL-6 mRNA of the internal drainage group at postoperative hour 0,1,2,4,12,24,48,72 were significantly lower than those of the control group and the external drainage group (P ＜ 0.05).Conclusions Both internal and external drainage can improve liver regeneration of obstructive jaundice rats following partial hepatectomy,while the effect of internal drainage is superior.Internal biliary drainage has influence on the expression of STAT3 by decreasing the levels of TNF-α and IL-6,and help to improve liver regeneration of obstructive jaundice rats following partial hepatectomy.

AIM: To investigate the effect of Qingrehuayuziyin Fang on lymphocyte apoptosis and expression of Fas and FasL in peripheral blood in the patients with systemic lupus erythematosus(SLE).METHODS: Eighty patients with SLE were selected and divided randomly into two groups,40 in the therapy group and 40 in control group respectively.Patients were get the treatment of Qingrehuayuziyin Fang combined hormone(prednisone) as therapy group and get hormone treating only as control group.After treating three months,lymphocyte were collected to be detected the rate of apoptosis by flow cytometer.Meanwhile,the expression of Fas and FasL were analyzed by RT-PCR.RESULTS: After three months treating,the rate of lymphocyte apoptosis was decreased significantly in therapy group compared with that in control group(P

Objective To evaluate the clinical value of CT perfusion (CTP) imaging for providing quantitative information about angiogenesis in patients with lung carcinoma and investigate the correlation of CTP enhancement parameters and histological microvessel density (MVD) with lymphatic involvement in peripheral lung carcinoma. MethodsFifty-three patients with pathology-proved peripheral lung carcinoma underwent CT perfusion scan before operation. The enhancement parameters of CTP were calculated based on the time-density curves (TDC) of fist pass phase. All cases were classified into two groups according to pathologic results: tumor with and without lymph node involvement. Two-sample t test was used for the statistics. The ROC curve was used to assess the efficiency of the enhancement parameters of CT perfusion and MVD for predicting lymphatic involvement.Results Tumors with lymph node involvement had significantly higher value of MVD than those without lymph node involvement (64.69±16.34 and 42.67± 16.78, respectively,t=4.84,P<0.01). Tumors with lymph node involvement had significantly higher value of CTP enhancement parameters (PH, M/A, PV) than those without lymph node involvement [PH= (41.79±15.50) and (29.99±10.91) HU,M/A =0.24±0.09 and 0.15±0.06, PV=(2.14±1.09) and (1.27±0.53) ml·min~(-1)·ml~(-1), t=3.21,3.95, 3.66, P<0.01, respectively]. The CTP enhancement parameters (PH, M/A, PV) of lung cancer correlated positively with the MVD, the highest correlation coefficient was between the PV and MVD (r=0.716, P<0.01). MVD and PV had higher values for predicting lymph node involvement in ROC curve analysis.The sensitivity, specificity and accuracy for predicting lymph node involvement were 80.8%, 81.5% and 81.1% or 84.6% ,85.2% and 84.9% respectively if MVD>52/0.74 mm~2 or PV>1.52 ml·min~(-1)·ml~(-1). ConclusionThe CT perfusion PV and histological MVD have good correlation with lymph node involvement in peripheral lung carcinoma and are important predicting parameters before operation.

Adolescent ; Adult ; Child ; Child, Preschool ; Electrocoagulation ; methods ; Female ; Humans ; Hypothermia, Induced ; Male ; Middle Aged ; Prospective Studies ; Tonsillectomy ; methods ; Young Adult