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Biomedical subjects

J Chen

Publications and source records attributed to J Chen.

At least 1,009 records · Page 56Linked to original sources
PubMed2000

Overexpression of Bcl-2 partly inhibits apoptosis of human cervical cancer SiHa cells induced by arsenic trioxide.

OBJECTIVE: To study the biological effect of arsenic trioxide (As2O3) on human cervical cancer SiHa cells and SiHa cells overexpressing bcl-2 gene. METHODS: SiHa cells with overexpression of Bcl-2 (SiHa-Bcl2 cells) were established by transfecting SiHa cells with Bcl-2 expression vector. The sensitivities of SiHa and SiHa-Bcl2 cells to As2O3 were determined using MTT (Thiazolyl blue) reduction and colony forming ability assay, morphological analysis, flow cytometric analysis, DNA agarose gel electrophoresis, in situ cell death detection (TUNEL), Northern blot, RT-PCR and Western blot. RESULTS: As2O3 inhibited the growth of SiHa cells and induced G2/M arrest and apoptosis of the cells. RT-PCR and Western blot analysis revealed that As2O3 induced SiHa cell apoptosis possibly via inhibiting the expression of HPV16 E7 and decreasing the expression of c-myc. However, we found that SiHa-Bcl2 cells partly resisted As2O3 induced apoptosis, which might be related to the prevention of the down-regulation of HPV16 E7 and c-myc gene expression. Nevertheless, As2O3 at a high concentration could still induce apoptosis of SiHa-Bcl2 cells mainly via decreasing Bcl-2 expression and slightly inhibiting viral gene expression. CONCLUSION: As2O3 is an inducer of the apoptosis of human cervical carcinoma cells and the cells overexpressing Bcl-2 can partly resist As2O3 induced apoptosis, but the exact mechanism is unclear.

Antineoplastic Agents↗
PubMed2000

Mitochondrial gene variation in type 2 diabetes mellitus: detection of a novel mutation associated with maternally inherited diabetes in a Chinese family.

OBJECTIVE: To explore the relationship between type 2 diabetes mellitus and the mutation(s) in mitochondrial DNA. METHODS: According to the previous literature, the fragment of mitochondrial DNA from nucleotide 3153 to 3551, which had shown high frequency of point mutation, was scanned with the technique of polymerase chain reaction--single strand conformation polymorphism (PCR-SSCP) in Chinese normal control, type 2 diabetic population, and 12 families suffered from maternally inherited type 2 diabetes mellitus. Direct sequencing was applied to detect the fragments with abnormal conformation. RESULTS: No special band was found in SSCP electrophoreses in Chinese normal control, and only one subject (No. 81) of diabetic population indicated the abnormality in SSCP study, which was affirmed to be a silent point mutation of T to C at nucleotide 3336 inducing no change in amino acid (ATT-->ATC, Ile). Pedigree 25,001 was the only family that exhibited strongly different SSCP characteristic from the other 11 ones, which was confirmed to be caused by a single point mutation mt3285T-->C/T in the coding region of tRNA(Leu(UUR)) gene by the technique of direct sequencing. CONCLUSIONS: The variation within mt DNA 3153-3551 is not the major cause of type 2 diabetes in Chinese population suffered from this disease in this study. The point mutation T-->C/T at the mitochondrial nucleotide 3285, which was found in pedigree 25,001, is located in the highly conservative region of tRNA(Leu(UUR)) gene. It is strongly suggested that this mutation cause the conversion in the 3-dimentional structure of tRNA(Leu(UUR)), which might disturb the normal translation and lead to the impairment in mitochondrial oxidative phosphorylation characterized by the defects of the polypeptides involved in the respiratory chain. Thus, insulin secretion deficiency and insulin resistance might occur.

Adult↗
PubMed2000

The effects of glucose, insulin and oxidized low density lipoprotein on apoptosis in vascular endothelial cells.

OBJECTIVE: To study the effects of high concentrations of glucose, insulin and oxidized low density lipoprotein (ox-LDL) on apoptosis in cultured bovine aortic endothelial cells (ECs). METHODS: For qualitative determination of EC apoptosis, acridine orange (AO)/ethidium bromide (EB) staining and DNA agarose gels electrophoresis were used. Cellular DNA fragmentation ELISA measured apoptosis by quantitating the fragmentation of 5-bromo-2'-deoxyuridine-labeled DNA. RESULTS: High concentrations of glucose (20 mmol/L, 40 mmol/L), insulin (3000 microU/ml) and ox-LDL (50 micrograms/ml, 100 micrograms/ml) induced concentration- and time-dependent apoptosis in ECs. They had a synergetic effect on EC apoptosis. The combined effect of high concentration of glucose, insulin and ox-LDL was greater than any two of them; the effect of two was greater than one alone. Low concentration of insulin (30 microU/ml) decreased apoptosis in ECs induced by high concentrations of glucose (40 mmol/L), but no similar effect occurred with ox-LDL (100 micrograms/ml). CONCLUSION: High ambient glucose, insulin and ox-LDL can induce excessive apoptosis in cultured ECs, and low ambient insulin can prevent EC apoptosis. Excessive EC apoptosis induced by the separate or synergetic effect of hyperglycemia, hyperinsulinemia and hyperlipidemia may be one of the reasons for loss of endothelial integrity, dysfunction of the vascular endothelium and increased plasma membrane permeability, which are all involved in the development of diabetic macrovascular complications.

Animals↗
PubMed2000

[Pelvic exenteration of advanced gynecological malignacies: a report of 18 cases].

OBJECTIVE: To investigate the role of pelvic exenteration in the treatment of advanced gynecological malignances. METHODS: Eighteen patients with cervical cancer in 8, vulvar cancer in 8, and vaginal cancer in 2, who underwent pelvic exenteration at the Cancer Hospital of Shanghai Medical University between 1970 and 1990 were retrospectively analyzed. RESULT: Median age was 52 years (range 27-65). One woman received surgery of total pelvic exenteration, 10 anterior and 7 posterior exenteration. The 3,5-year survival rates were 72%, 50%, respectively. Postoperative morbidity was 16%, and the surgical mortality was 0%. Bowel obstruction occurred in 2 of 18 cases, one of them was treated surgically. CONCLUSIONS: (1) Patients with advanced central type pelvic neoplasms can be successfully treated with exenteration; (2) The patients should be properly selected prior to and in operation, and the procedures must be performed specifically, particularly in exploration stage.

Adult↗
PubMed2000

Modulation of transforming growth factor beta to platelet-derived growth factor receptor-alpha of human osteoblasts.

OBJECTIVE: To investigate the mechanism and the significance of TGF beta in modulating the expression of Platelet-Derived Growth Factor Receptor-alpha (PDGFR-alpha) in human osteoblasts. METHODS: The osteoblasts were isolated from human fetal calvaria. The percentage of cell increase (PCI) in every 4 hours was calculated to demonstrate the proliferation of osteoblasts affected by PDGF-AA and TGF beta. The osteoblasts were cultured with TGF beta for 24 hours and with PDGF-AA for another 24 hours, and the cells proliferation was shown by PCI too. The osteoblasts were cultured with TGF beta for 24 h, and the PDGFR-alpha of the cells were measured by immunofluorescent analysis. RESULTS: PCI was increased by 48.2% and 22.4% after PDGF-AA and TGF beta were added into the medium for 24 hours respectively (P < 0.05), and PCI decreased after the removal of the two cytokines. Preincubated with TGF beta for 24 hours and then stimulated with PDGF-AA, PCI grew slowly. TGF beta downregulated the expression of the PDGFR-alpha. CONCLUSION: TGF beta can downregulate the mitogenesis of PDGF-AA by lowering the number of PDGFR-alpha.

Cell Division↗
PubMed2000

99mTc-MIBI and 99mTc-MDP scintimammography for detecting breast carcinoma.

OBJECTIVE: To assess the value of scintimammography with both 99mTc-MIBI and 99mTc-MDP in detecting breast cancer. METHODS: A total of 35 women with clinical findings of suspicious breast lesions were studied with both 99mTc-MIBI and 99mTc-MDP scintimammography. All patients underwent surgery within one week and the final diagnostic results (histopathological) were obtained. RESULTS: Eighteen of 35 abnormalities of breast were pathologically confirmed as breast cancer and 17 as benigN lesions. In this group of patients studied, the sensitivity, specificity and accuracy of 99mTc-MIBI scintimammography were 77.8%, 88.2% and 82.9%, respectively and those of 99mTc-MDP scintimammography were 72.2%, 88.2% and 80.0%, respectively. There was no significant difference between 99mTc-MIBI and 99mTc-MDP scintimammography. CONCLUSION: This study showed the high diagnostic accuracy of both 99mTc-MIBI and 99mTc-MDP scintimammography in detecting breast cancer. Both can be used as non-invasively assess breast cancer invasiveness before surgery.

Adult↗
PubMed2000

Association of coagulation factor VII with the risk of myocardial infarction in the Chinese.

OBJECTIVE: To elucidate the association of plasma factor VII coagulant activity (FVIIc) with the risk of myocardial infarction (MI) and to assess the influence of factor VII gene MspI polymorphism and lipid metabolism on FVIIc in the Chinese. METHODS: A total of 137 patients with angiographically confirmed MI and 125 healthy individuals were evaluated retrospectively. Plasma FVIIc was measured by one-stage prothrombin time, and FVII genotype was determined after MspI digestion of polymerase chain reaction-amplified genomic DNA. Serum lipid levels were assessed by routine methods. RESULTS: MI patients had significantly higher levels of FVIIc (119.5% +/- 22.7% vs 99.9% +/- 21.8%, P < 0.01) and total serum cholesterol (5.80 +/- 1.06 mmol/L vs 5.53 +/- 1.08 mmol/L, P < 0.05) than controls, but only FVIIc independently correlated with the risk of MI (OR = 1.04, P < 0.01). There were no significant differences in FVII genotype or allele frequency between patients and controls (P > 0.05). Subjects with the Gln353 allele were associated with significantly lower FVIIc levels than Arg353 homozygotes (99.7% +/- 19.3% vs 111.4% +/- 24.6%, P < 0.05). Serum triglyceride was positively correlated with plasma FVIIc in both control (r = 0.25, P < 0.01) and case (r = 0.87, P < 0.01) groups, but this correlation was restricted to Arg/Arg genotype (r = 0.68, P < 0.01). A significant correlation of total serum cholesterol with FVIIc only appeared in Arg/Arg homozygotes (r = 0.17, P < 0.01). CONCLUSIONS: Our findings support the role of plasma FVIIc as a risk factor for MI in Chinese. Plasma triglyceride and FVII gene MspI polymorphism are two independent determinants of FVIIc. Assay of this polymorphism will be helpful in determining who will benefit most from lipid-lowing therapy.

Adolescent↗
PubMed2000

[Cytoreductive surgery in the management of stage IV epithelial ovarian cancer].

OBJECTIVE: To determine the role of cytoreductive surgery in patients with stage IV epithelial ovarian cancer. METHODS: From Jan. 1986 to Dec. 1997, 71 patients with stage IV epithelial ovarian cancer who were surgically treated in our hospital were retrospectively reviewed. Survival was calculated by Kaplan-Meier method with differences in survival estimated by Log-rank test. Independent prognostic factors were identified by the COX's stepwise regression model. RESULTS: Thirty (42.3%) of 71 patients were successfully debulked (< or = 1 cm) at the time of initial surgery. The estimated 5-year total survival rate was 6.1%. There was a significant difference in survival between patients optimally (13.7%) vs. suboptimally (0.0%) cytoreduced, with an estimated medium survival of 23 months in optimal group vs. 9 months in suboptimal group (P < 0.001). When the variables were factorized, optimal cytoreduction could get the greatest benefit. Only in patients with malignant pleural effusion or positive supraclavicular lymph node. Multivariate analysis revealed that size of residual disease and ascites were independent factors for both overall and progression-free survival (P < 0.05). CONCLUSIONS: Optimal cytoreductive surgery is an important determinant of survival in women with stage IV epithelial ovarian cancer, especially in those with malignant pleural effusion or positive supraclavicular lymph node pathology.

Adult↗
PubMed2000

[Combined hepatic artery chemoembolization and portal vein chemotherapy after radical resection of hepatocellular carcinoma to prevent recurrence].

OBJECTIVE: To study the value of combined hepatic artery chemoembolization (HACE) and portal vein chemotherapy (PVC) after radical resection of hepatocellular carcinoma (HCC) to prevent recurrence. METHODS: From August 1991 to July 1995, 81 HCC patients were undergone radical tumor resection. After operation, combined treatment with HACE and PVC was given in group I (28 cases), HACE alone in group II (30 cases), nothing in group III (28 cases). All patients were followed up over 3 years. RESULTS: Recurrence rate at one year after surgery was significantly lower in group I and II than in group III; at two years, it was lower in group I than in group II and III. Survival rate at one year was notably higher in group I and II than in group III; at 2 years, it was higher in group I than in group II and III. Recurrence rate and survival rate were similar in group I and group II at 3 and 5 years after surgery. Tumor larger than 5 cm, no capsule, multiple foci, AFP > 400 micrograms/L were high risk factors of postoperative recurrence. CONCLUSION: After radical resection of HCC, combined use of HACE and PVC is superior to HACE alone to reduce recurrence rate and to increase survival rate within 2 years after operation. Such remarkable difference no more exists at 3 and 5 years following operation.

Adult↗
PubMed2000

[Transbronchial needle aspiration in routine bronchoscope practice].

OBJECTIVE: To evaluate the yield of transbronchial needle aspiration (TBNA) in a clinical routine bronscopy practice after training under the guide by CT scanning. METHODS: Using Wang TBNA System and CT scanning methods to define the site in airway for puncturing the enlarged mediastinal lymphnode. The positive rate of TBNA was 64%, almost equal to the positive rate (61%) of the method by operating directly under CT scanning. TBNA was performed on 100 consecutive patients with 152 enlarged mediastinal nodes undergoing diagnostic fiberoptic bronchoscopy. RESULT: The positive rate (64%) was equal to the positive rate (61%) under the CT guide. CONCLUSIONS: CT guiding TBNA is very useful for training doctors to learn the TBNA technique, and TBNA can be done very well and play an important role in routine bronchoscope practice.

Biopsy, Needle↗
PubMed2000

[The effects of RA538 and antisense c-myc on cervical cancer cell lines with high expression of bcl-2 gene].

OBJECTIVE: To study the effects of recombinant adenovirus with RA538 or antisense c-myc insert on cervical cancer cell lines with high expression of bcl-2 gene. METHODS: Cervical cancer cell lines HeLa and SiHa were transduced with full length bcl-2 cDNA by lipofectin and cell clones with stable expression of bcl-2 were selected. They were then transfected with recombinant adenovirus containing RA538 (Ad-RA538), antisense c-myc (Ad-ASc-myc) or LacZ (Ad-LacZ) gene. Morphologic and molecular changes of the transfected cancer cells were examined by light microscopy, MTT, RT-PCR and Northern blot. RESULTS: The bcl-2 cDNA was successfully transferred into HeLa and SiHa cells. Two cell lines, called HeLa-bcl2 and SiHa-bcl2 with high expression of bcl-2 gene were generated. Ad-RA538 and Ad-ASc-myc transfection both could inhibit cell growth and induce apoptosis of HeLa and SiHa cells, and inhibit their expression of c-myc and bcl-2 genes. However, although Ad-RA538 and Ad-ASc-myc had some inhibitory effect on bcl-2 and c-myc gene expression by HeLa-bcl2 and SiHa-bcl2 cells, they could only slightly inhibit cell growth and weakly induce apoptosis. CONCLUSION: Ad-RA538 and Ad-ASc-myc can to certain extent inhibit cell growth and induce apoptosis of two cervical cancer cell lines. They have little such effect when these cell lines have over-expressed bcl-2 by transduction of exogenous bcl-2 gene.

Antineoplastic Agents↗
PubMed2000

[Evaluation of ten-year results of cancer prevention and treatment in Changle City with high incidence of gastric cancer].

OBJECTIVE: To evaluate the results of cancer prevention and treatment over a 10-year period (1988-1997) in Changle City with high incidence of gastric cancer. METHODS: The results were analysed with sick rate random test, trend test, GM and Kaplan-Meier method with SAS statistical software. RESULTS: During the ten years, the sick rate of malignant tumors in male residents initially increased but then decreased. Gastric cancer had a tendency to decline. There was no obvious change for females. By short-term prediction, the sick rate of malignant tumors and gastric cancer would decrease, and that of liver cancer remain steady. The life expectancy of male residents increased 4.2 years and that of female residents increased 1.8 years from 1988 to 1997 if cancer death was ignored, but the increase was not significant if only deaths from gastric and liver cancers were excluded. The 5-year survival rate of gastric cancer and liver cancer increased 8.8% and 29.3% from 1988 to 1990, respectively. The cumulative risk rate of gastric cancer in males was 3 times as high as that of females, and that of liver cancer in males was 2.5 times as high as that of females. CONCLUSION: Sustained measures of cancer prevention and treatment woult anticipate further improvement of health status of Changle's residents in the years to come.

Aged↗
PubMed2000

[Experimental study on effect of folium Ginkgo biloba in treating pulmonary interstitial fibrosis in rats].

OBJECTIVE: To evaluate the therapeutic effect and mechanism of folium Ginkgo biloba (FGB) in treating pulmonary interstitial fibrosis (PIF) induced by bleomycin in rats. METHODS: PIF models of bleomycin-A5-induced pulmonary fibrosis were established in rats, they were treated by Bailuda, a preparation of FGB, and the pathological changes, collagen protein level, nuclear factor kB(NF-kB) activity, transforming growth factor beta (TGF-beta) mRNA expression and protein level of the lung tissue were measured. RESULTS: In the Bailuda treated group after treatment, amelioration of the pulmonary alveolitis and fibrosis were shown in pathological section (P < 0.05) and collagen protein content was lesser (P < 0.01) as compared with those in the model control group. After 1 week of Bailuda treatment, the NF-kB activity of pulmonary alveola macrophage lowered by 47.3%, and levels of TGF-beta mRNA expression and protein were all decreased (P < 0.05). CONCLUSIONS: Bailuda has definite effect in treating PIF. The mechanism may be through inhibiting the activity of NF-kB, decreasing TGF-beta mRNA expression and protein, so as to ameliorate the inflammation and fibrosis.

Animals↗
PubMed2000

[The relationship between clinical types of postinfarction angina and stenosis of ischemia-related artery].

OBJECTIVE: To approach the pathogenesis of postinfarction angina and set up its treatment guidelines. METHODS: 67 patients with postinfarction angina undergoing coronary angiography during the hospitalization were studied. RESULTS: (1) According to the clinical classification of angina pectoris, spontaneous angina is the most common type (43.9%); mixed angina is second (25.7%), effort angina and variant angina are relatively low frequency (16.7% & 13.6%). (2) Stenosis >or= 90% in the ischemia-related artery accounted for the anginal symptoms constituted 100%, 82.8%, 72.7% and 44.4% of the cases with mixed angina, spontaneous angina, effort angina and variant angina respectively. (3) Postinfarction angina caused by non infarction-related artery was relatively less frequent (8.9%). CONCLUSIONS: Severe residual stenosis of infarction-related artery is the main pathologic factor on the pathogenesis of postinfarction angina, so early interventional therapy or bypass surgery should be taken.

Adult↗
PubMed2000

[Evaluation of long-term community based intervention on cardiovascular diseases: 9-year follow up study of the mortality from the cohorts].

OBJECTIVE: To evaluate the effect of long-term intervention on all-causes mortality and the mortality of cardiovascular diseases. METHODS: In May 1987 in Beijing, 2 geographically separated community with a registered population of about 10 000 each were selected as either intervention or control community. In each community, a cohort containing 2 700 subjects (>/= 35 years) free of stroke was sampled. A baseline survey was administered to screen the eligible subjects for intervention. Death information from the cohorts was collected. RESULTS: By the end of Dec. 31, 1995, the 9-year cumulative all-causes mortalities were 3.51% (303/2 861) in the intervention cohort and 4.71% (390/2 760) in the control cohort. Cardiovascular diseases and neoplasm were the first and second leading causes of death in the cohorts. Both the all-causes mortality and the mortality of cardiovascular diseases were significantly lower in the intervention cohort than in the control group. The risk for dying of all-causes death was reduced by 22% (RR = 0.78, 95% CI: 0.67 approximately 0.91) and the risk for dying of cardiovascular diseases was reduced by 24% (RR = 0.76, 95% CI: 0.57 approximately 0.96) in the intervention cohort. CONCLUSION: Long-term community intervention for the risk factors of cardiovascular diseases can effectively reduce the mortality of cardiovascular diseases as well as all-causes mortality.

Adult↗
PubMed2000

[Effect of left ventricular diastolic dysfunction on pathogenesis of angina decubitus].

OBJECTIVE: To investigate the effect of left ventricular diastolic dysfunction on the pathogenesis of angina decubitus. METHODS: The study population consisted of three groups: (1) group 1, 31 patients with angina decubitus who had ejection fraction > 50%; (2) group 2, 20 patients with coronary artery disease but without angina decubitus; group 2 and 1 were matched for age, EF and extent of coronary artery disease; (3) group 3, 20 patients without cardiovascular diseases. RESULTS: Left ventriculography (LVG) showed that LV first 1/3 filling fraction (1/3 FF) and LV late 1/3 FF were 0.30 +/- 0.12, 0.41 +/- 0.12, 0.46 +/- 0.07 and 0.36 +/- 0.09, 0.31 +/- 0.08, 0.29 +/- 0.06 in groups 1 to 3 respectively. LV first 1/3 FF was significantly lower in group 1 than in group 2 and 3 (both P < 0.001), but LV late 1/3 FF was much higher in group 1 than in groups 2 and 3 (P < 0.05 and P < 0.01, respectively). Left ventricular end-diastolic pressure (LVEDP) was markedly increased before and after LVG in groups 1 and 2 as compared with group 3 (P < 0.001 and P < 0.05, respectively). The difference of LVEDP caused by left atrial contraction (LACD) was much higher before and after LVG in group 1 than in group 3 (P < 0.01 and P < 0.001, respectively). However, there were significant differences in LVEDP and LACD tested between before and after LVG in group 1 (both P < 0.01). No statistical differences were found in LVEDP and LACD tested between before and after LVG in both group 2 and group 3. CONCLUSION: Patients with angina decubitus have LV diastolic dysfunction, which may be closely related to the pathogenesis of angina decubitus.

Adult↗
PubMed2000

[Changes and significance of concentrations of serum vascular endothelial growth factor in patients with pregnancy induced hypertension].

OBJECTIVE: To detect the changes of concentrations of serum vascular endothelial growth factor (VEGF) in patients with pregnancy induced hypertension (PIN) as well as to explore the relationship between VEGF and pathogenesis of PIN. METHODS: Serum VEGF concentrations in 23 healthy nonpregnant women (nonpregnant group), 30 normal pregnant women (normal pregnancy group) and 37 women with PIH (PIH group) were measured by sandwich enzyme-linked immunoadsorbent assay (ELISA). RESULTS: Serum concentrations of VEGF were significantly higher in normal pregnancy group (149.39 +/- 27.15) ng/L than those in nonpregnant group (11.98 +/- 3.99) ng/L (P < 0.001), peaking in the second trimester of pregnancy (183.84 +/- 49.02) ng/L and decreasing in the third trimester (118.37 +/- 34.29) ng/L. Serum VEGF concentrations (64.45 +/- 24.33) in PIH group were significantly lower than those in normal late pregnancy group (118.37 +/- 34.29) ng/L (P < 0.01). There was a trend that serum VEGF concentrations in PIH group decreased with the severity of PIH (P < 0.05). CONCLUSION: The decrease of VEGF may play and important role in the pathogenic mechanism of PIH.

Adult↗