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Biomedical subjects

Y Xiang

Publications and source records attributed to Y Xiang.

At least 55 records · Page 3Linked to original sources
PubMed2000

Effect of valsartan and fosinopril on catecholamine-induced cardiac hypertrophy.

AIM: To study the influence of angiotensin (Ang) II receptor antagonist (AT1) valsartan and angiotensin-converting enzyme (ACE) inhibitor fosinopril on the cardiac hypertrophy induced by catecholamine. METHODS: A cardiac hypertrophy model was produced by i.p. norepinephrine (NE) 1.5 mg.kg-1.d-1 x 15 d. The animals were divided into four groups: 1) control (sodium chloride), 2) NE, 3) NE + fosinopril, 4) NE + valsartan. Fosinopril ig 15 mg.kg-1.d-1 x 15 d, valsartan ig 30 mg.kg-1.d-1 x 15 d. RESULTS: Valsartan ig 30 mg.kg-1.d-1 x 15 d and fosinopril ig 15 mg.kg-1.d-1 x 15 d prevented left ventricular hypertrophy induced by NE and decreased the content of collagen in myocardium; valsartan and fosinopril both elevated the myosin ATPase activity, Na+, K(+)-ATPase activity in membrane, and Ca(2+)-ATPase activity in mitochondrias. Apoptosis was induced in cardiomyocytes by catecholamine. Valsartan and fosinopril both inhibited apoptosis, and no significant differences were found in the apoptotic index between the two treatment groups. CONCLUSION: Valsartan and fosinopril prevent the remodeling of cardiac hypertrophy induced by norepinephrine. Cardiac myocyte apoptosis may play a key role in the heart remodeling.

Angiotensin Receptor Antagonists↗
PubMed2000

[Prediction of malignant transformation of hydatidiform mole by mRNA determination of matrix metalloproteinases and tissue inhibitor of metalloproteinases].

OBJECTIVE: To investigate the relationship between the messenger RNA(mRNA) levels of matrix metalloproteinases(MMP-9, MMP-2) and tissue inhibitor of metalloproteinase (TIMP-1, TIMP-2) and malignant transformation of hydatidiform mole. METHODS: Total RNA were isolated from tissues of 22 normal chorionic villi samples and 37 cases of hydatidiform mole. The mRNA expression of MMP-9, MMP-2, TIMP-1, TIMP-2 genes were determined by RT-PCR. RESULTS: The differences of the mRNA expression of MMP-9, MMP-2, TIMP-1, TIMP-2 genes in the tissues of hydatidiform mole and normal preganacy villus were not significant (P > 0.05). The ratio of MMP-9/TIMP-1 in molar tissues with malignant transformation was higher than those in molar tissues without malignant transformation and in normal villus. CONCLUSION: It is a correlative relation beween MMP-9/TIMP-1 and malignancy of hydatidiform mole. The ratio of MMP-9/TIMP-1 might be used as an index for prediction of malignant transformation of hydatidiform mole.

Adult↗
PubMed2000

[Fibronectin or RGD peptide promotes nitric oxide synthesis of rabbit bronchial epithelial cells].

To find out whether the extracellular matrix component fibronectin plays a regulatory and protective role in bronchial epithelial cells, the present study was undertaken to detect the NO released from primary cultured rabbit bronchial epithelial cells (BEC) and the activity of NO synthesase (NOS) in cells. Stress with ozone was taken as the positive control, and the effects of fibronectin (Fn) or its specific sequence Arg-Gly-Asp (RGD peptide) was observed. The results showed: (1) Ozone stress enhanced NO release from BEC, and treatment with Fn also promoted the NO production. The effect of Fn could be blocked by calmodulin inhibitor W(7). (2) Both Fn and RGD showed a dose-dependent promotion on NO release. (3) The NOS activity was significantly elevated in Fn treated group and the effect of Fn was abolished by W(7). A dose-response relation in NOS activity was observed in either Fn treated or RGD treated group. It is concluded that the binding of fibronectin or its specific sequence RGD peptide with integrins of BEC plays a role in upregulating the NOS activity and the NO release, and calmodulin may take part in the pathway of signal transduction.

Animals↗
PubMed2000

[Study on the volatile oil of Nardostachys chinensis].

The volatile oil of Nardostachys chinensis Batal has been studied by GC-MS, and 21 compounds have been isolated and identified. The total content of the components are 88.51%. Major compounds have been identified as Calarene (29.44%). delta 1(10)-Aristolenone-2 (16.57%) and Jatamansinol (8.80%).

Gas Chromatography-Mass Spectrometry↗
PubMed2000

The role of hysterectomy in the therapy of gestational trophoblastic tumor.

OBJECTIVE: To evaluate the role of hysterectomy for patients with gestational trophoblastic tumor. METHODS: We retrospectively analyzed 68 cases of gestational trophoblastic neoplasia treated by hysterectomy from 1985 to approximately 1997 at PUMC hospital. Thirty-eight cases were diagnosed of choriocarcinoma and 30 were invasive mole. RESULTS: Twenty-three elder patients who didn't desire to preserve fertility were selected for hysterectomy after shorter courses of chemotherapy, 22 of them had a complete remission (95.6%), the total average courses of chemotherapy was 4.2. Of twenty-seven chemorefractory cases who were suspected of a refractory isolated lesion in the uterus, delayed hysterectomy as an adjunct to chemotherapy was performed, 20 of them got a complete remission (71.1%), the total average courses of chemotherapy were 9.4. Emergency hysterectomy is indicated in 18 patients with uterine perforation or life-threatening hemorrhage, 17 cases had a complete remission (94.4%), the total average courses of chemotherapy were 7.6. CONCLUSION: Although the development of effective chemotherapy has resulted in improved survival of patients with gestational trophoblastic tumor, hysterectomy remains an important adjuncts in the treatment of a selected subset of patients; in order to operate more completely and prevent recurrence, it's better to perform extended hysterectomy for the indicated patients.

Adult↗
PubMed2000

[Expression of epidermal growth factor receptor in gestational trophoblastic tumours].

OBJECTIVE: To investigate the expression of epidermal growth factor receptor (EGFR) in gestational trophoblastic tumours and its clinical significance. METHODS: Placentas of 10 normal early pregnancies, 20 molar pregnancies, 10 samples from invasive mole and 8 samples of choriocarcinoma were used for the study. EGFR expression was evaluated by immunohistochemistry using monoclonal antibody. RESULTS: EGFR was expressed both in normal chorionic villi and tissues of trophoblastic tumours. EGFR was expressed more strongly in normal chorionic villi and non-malignant transformed hydatidiform mole than in malignant transformed molar pregnancies and malignant trophoblastic tumours (P < 0.05). Univariate and multivariate analysis indicated that EGFR immunostaining intensity was significantly related to the clinical stage in malignant trophoblastic tumours (P = 0.026, OR = 9.874). CONCLUSION: EGFR expression could be used as an index for prediction of malignant transformation of hydatidiform mole and staging of malignant trophoblastic tumours.

Adult↗
PubMed2000

[Diagnosis and management of gestational trophoblastic tumor with liver metastases].

OBJECTIVE: To evaluate management options and clinical prognosis for women presenting gestational trophoblastic tumor (GTT) with liver metastases. METHODS: We retrospectively analyzed sixteen GTT patients with liver metastases treated in the Peking Union Medical College (PUMC) hospital from 1985 to 1998. All were treated with 5-FU combined chemotherapy or EMA/CO regimen. Eight of them received hepatic artery infusion chemotherapy. Treatment outcome was measured by beta subunit human chorionic gonadotropin assay (beta-hCG) and by imaging studies which included ultrasound and computerized tomography. RESULTS: Of 16 cases, 4 achieved complete remission; biochemical remission was obtained in 2 patients who were alive with residual tumor; 10 patients died of the disease. The overall survival rate was 37.5% (6/16). CONCLUSIONS: The outcome for women presenting with liver metastases from GTT is poor. Early diagnosis and prompt initiation with vigorous multi-agent chemotherapy given through multi-routes are emphasized for improving the treatment outcome.

Adult↗
PubMed1999

IL-18 binding and inhibition of interferon gamma induction by human poxvirus-encoded proteins.

Molluscum contagiosum virus (MCV) is a common, human poxvirus that causes small papular skin lesions that persist for long periods without signs of inflammation. Previous studies revealed that MCV encodes a family of proteins with homology to mammalian IL-18 binding proteins. IL-18 is a proinflammatory cytokine that induces synthesis of interferon gamma, activates NK cells, and is required for a T-lymphocyte helper type 1 response. We expressed and purified the proteins encoded by the MC53L and MC54L genes of MCV, as well as their human and murine homologs. All four recombinant proteins were able to bind with high affinity to human and murine IL-18 molecules and inhibited IL-18 mediated interferon gamma production in a dose-dependent manner. The pirating of IL-18 binding proteins by poxviruses and their use as decoy receptors is consistent with the critical role of IL-18 in defense against virus infections and provides a mechanism for evasion of the immune system by MCV.

Animals↗
PubMed1999

Identification of human and mouse homologs of the MC51L-53L-54L family of secreted glycoproteins encoded by the Molluscum contagiosum poxvirus.

Molluscum contagiosum virus (MCV) is a human poxvirus that produces small, benign skin tumors primarily in young children and encodes proteins that modulate the host immune response. The MC51L, MC53L, and MC54L open reading frames of MCV have significant amino acid sequence similarities and related proteins are encoded by other poxviruses. These three MCV genes were individually expressed in mammalian cells as glycosylated and secreted proteins. A database search detected partial sequences of homologous human and mouse cDNAs; determination of the complete sequences confirmed the homology and indicated potential signal peptides and N-glycosylation sites as well as a pattern of cysteines that are conserved in the viral proteins. The human gene, which was mapped to chromosome 11q13, was highly expressed in spleen and lymph nodes, suggesting an immune modulatory role. The latter finding is consistent with a recent report (Novick et al., 1999, Immunity 10, 127-136) that the human protein binds IL-18, suggesting an anti-inflammatory role for the poxvirus homologs.

Amino Acid Sequence↗
PubMed1999

Plant paralog to viral movement protein that potentiates transport of mRNA into the phloem.

CmPP16 from Cucurbita maxima was cloned and the protein was shown to possess properties similar to those of viral movement proteins. CmPP16 messenger RNA (mRNA) is present in phloem tissue, whereas protein appears confined to sieve elements (SE). Microinjection and grafting studies revealed that CmPP16 moves from cell to cell, mediates the transport of sense and antisense RNA, and moves together with its mRNA into the SE of scion tissue. CmPP16 possesses the characteristics that are likely required to mediate RNA delivery into the long-distance translocation stream. Thus, RNA may move within the phloem as a component of a plant information superhighway.

Amino Acid Sequence↗
PubMed1999

[Methotrexate combined chemotherapy for chemorefractory gestational trophoblastic tumour].

OBJECTIVE: To evaluate the response rate and toxicity of etopside, methotrexate, kengshengmycin, cyclophosphamide and vincristine (EMA/CO) regimen for women with chemorefractory gestational trophoblastic tumour. METHODS: Fifty-one patients with chemorefractory gestational trophoblastic tumour were treated by EMA/CO regimen. Operative excision and (or) selective arterial infusion as adjuncts to chemotherapy were performed in a selected subset of patients. The response and toxicity were assessed after treatment. RESULTS: Fifty-one patients received 352 cycles of the study regimen. The median number of courses for each patient was 6.9. Thirty-three cases (64.7%) achieved a complete remission while 14 patients (27.5%) had a partial remission, 4 cases showed nonresponse. Two (6.7%) of 30 complete responders developed recurrences. The main complications for EMA/CO chemotherapy were myelosuppression and gastrointestinal symptoms. CONCLUSION: The EMA/CO regimen is an effective treatment for chemorefractory gestational trophoblastic tumour, and the chemotherapeutic results can be further improved while combined with arterial infusion chemotherapy and surgery in the selected patients.

Adult↗
PubMed1999

[Application and comparison of meta and pooled analyses in the study of cancer epidemiology].

OBJECTIVE: To introduce two comprehensive methods of analysis, Meta and pooled, frequently used in cancer epidemiology, and to compare them with authentic examples. METHODS: From data of a multicenter case-control study of lung cancer risk factors among non-smoking females, "family history of lung cancer" and "smoking history of parents" were the two variables selected for analysis. Based on the data from individual centers, Meta and pooled methods were employed to perform comprehensive analysis and the results compared. In the former, both fixed and random effect models were considered. RESULTS: When the data from individual study centers were analyzed, odds ratios (OR) differed. The OR of variable "family history of lung history" was statistically significant in Shanghai, while that of variable "smoking history of parents" was statistically significant in Harbin. Given the fixed effect model, the results of analysis were identical under different conditions of analysis (non-adjusted, adjusted with Mantel-Haenszel methods and multivariate logistic analysis). The results were similar when random effect model was used. In case the fixed effect model was not valid and there were some differences obtained by the two methods, combined parameters calculated from random effect model would be used. Stratified logistic model seemed better than basic logistic model in the pooled analysis. CONCLUSION: The results from Meta and pooled comprehensive analyses are essentially consistent.

Female↗
PubMed1999

[The role of hysterectomy in the therapy of gestational trophoblastic tumor].

OBJECTIVE: To evaluate the role of hysterectomy for patients with gestational trophoblastic tumor. METHODS: A total of 68 cases of gestational trophoblastic neoplasia treated by hysterectomy from 1985-1997 at PUMC hospital was retrospectively analyzed. Thirty-eight cases were diagnosed as choriocarcinoma and 30 as invasive mole. RESULTS: Twenty-three elder patients who didn't desire to preserve fertility were selected for hysterectomy after short courses of chemotherapy. Twenty-two of them had complete remission (95.6%). The average total course of chemotherapy was 4.2. Of twenty-seven chemo-refractory cases who were suspected of an isolated lesion in the uterus, delayed hysterectomy as an adjunct to chemotherapy was performed. Twenty of them achieved complete remission (74.1%), with an average 9.4 courses of chemotherapy. Emergency hysterectomy was indicated in 18 patients with uterine perforation or life-threatening hemorrhage. Seventeen of the emergent cases had complete remission (94.4%), who had received an average 7.6 courses of chemotherapy. CONCLUSION: Although the development of effective chemotherapy has resulted in improved survival of patients with gestational trophoblastic tumor, hysterectomy remains an important adjunct treatment in a selected subset of patients. Modified radical hysterectomy is recommended for the indicated patients.

Female↗
PubMed1999

[Reversion of HBV-related liver fibrosis and early cirrhosis by baicao rougan capsule].

OBJECTIVE: To observe the therapeutic effect of herbal compound, Baicao Rougan Capsule on human liver fibrosis and early cirrhosis associated with chronic hepatitis B. METHODS: Forty-two patients with liver fibrosis and 10 cases early cirrhosis were treated with a herbal compound for six months. Two liver biopsies were performed before and after treatment, their serum samples were collected before, in the middle of and after the treatment, all samples were measured at the same time. RESULTS: Improvement of clinical symptoms and signs occurred in 75% to 91% of the patients, serum ALT lowered to normal level in 68%. The serum level of type IV collagen, laminin and hyaluronic acid were significantly reduced by the end of treatment (P < 0.05). Grading score was reduced from 7.79 +/- 6.15 to 5.36 +/- 3.95 after treatment (P < 0.05), while staging score was reduced from 7.39 +/- 5.55 to 5.26 +/- 4.36 (P < 0.05). CONCLUSION: Chinese herbal compound Baicao Rougan Capsule is effective in the treatment, and in the reversal of HBV related liver fibrosis and early cirrhosis.

Adolescent↗
PubMed1999

[Smoking, related cancers, and other diseases in shanghai: a 10-year prospective study].

OBJECTIVE: To explore the relationship between smoking and related diseases among residents of Shanghai. METHODS: A cross-sectional study on current smoking status among 213,800 residents aged 20 yr and over in Shanghai urban, suburb and rural areas was carried out during the early 1980s. The residents in the urban area were followed up for 12 years (1983 - 1994) and those in suburb and rural areas for 11 years (1984 - 1994). A Poisson regression model was used to estimate relative risks RRs of certain diseases for smoking adjusted for age with their 95% confidence intervals by sex and area among persons aged 40 yr and over at the beginning of the study. RESULTS: In the urban area, the RRs of death for smoking were 1.48 and 1.62 in males and females, respectively and for cancer death were 2.20 and 2.00. Statistically significant elevated RRs were seen for cancers of the lung and liver in both males and females and for cancers of the oesophagus, stomach, pancreas and bladder only in males. Significantly higher RRs were also observed for cerebrovascular disease, chronic bronchitis and emphysema, and pulmonary heart disease. RRs lower than in the urban area were found in the suburb and rural areas. The population attributable risks (%, PAR) for death due to smoking for males were estimated by area. PARs for death were 20.9, 18.9 and 16.3 in urban, suburb and rural areas, respectively. For all cancers, PARs were 40.0, 34.5 and 34.2 and for lung cancer were 71.7, 59.2 and 64.7. CONCLUSION: Smoking was associated with the mortality of some common cancers, chronic bronchitis, and emphysema, pulmonary heart, and cerebrovascular diseases.

China↗
PubMed1999

[A case-control study on relationship between body mass index and lung cancer in non-smoking women].

OBJECTIVE: To investigate the relationship between body mass index (BMI) and lung cancer in non-smoking women. METHODS: A population-based case-control study on lung cancer in non-smoking women was conducted during February 1992 to December 1993 in Shanghai. Totally, 504 cases of lung cancer of non-smoking women and 601 population controls were studied. RESULTS: The risk of lung cancer increased with the decrease of BMI. The odds ratio of lung cancer in non-smoking women was 1.95, as compared to controls with the highest quartile of their BMI, with a dose-response pattern (P < 0.0002 with chi(2) test for trend), adjusted for age, schooling and income. Non-conditional logistic regression analysis was used to adjust for some main risk factors found in other studies carried out at home, such as passive smoking, tea drinking, eye irritation by cooking oil fume, kinds of cooking oils, pulmonary tuberculosis, family history of lung cancer, age of menarche, menstrual cycle and dietary nutrition (including intake of vitamins C and E, beta-carotene, total fat and calorie), was used to adjust. There still existed relationship between BMI and lung cancer in non-smoking women after adjustment for those factors. Stratification analysis showed that there was relationship mainly between BMI and lung adenocarcinoma. CONCLUSION: BMI may be a risk factor for lung cancer in non-smoking women.

Adult↗
PubMed1998

PACS-1 defines a novel gene family of cytosolic sorting proteins required for trans-Golgi network localization.

We report the role of one member of a novel gene family, PACS-1, in the localization of trans-Golgi network (TGN) membrane proteins. PACS-1 directs the TGN localization of furin by binding to the protease's phosphorylated cytosolic domain. Antisense studies show TGN localization of furin and mannose-6-phosphate receptor, but not TGN46, is strictly dependent on PACS-1. Analyses in vitro and in vivo show PACS-1 has properties of a coat protein and connects furin to components of the clathrin-sorting machinery. Cell-free assays indicate TGN localization of furin is directed by a PACS-1-mediated retrieval step. Together, these findings explain a mechanism by which membrane proteins in mammalian cells are localized to the TGN.

Adaptor Protein Complex alpha Subunits↗