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Biomedical subjects

M Gao

Publications and source records attributed to M Gao.

At least 91 records · Page 5Linked to original sources
PubMed1999

Effect of immunosuppressive therapy, serum creatinine, and time after transplant on plasma total homocysteine in patients following heart transplantation.

OBJECTIVES: To determine the prevalence of hyperhomocysteinemia in heart transplant recipients, and to assess the effect of renal function and immunosuppressive medication on total plasma homocysteine (tHcy) levels. BACKGROUND: Elevated plasma tHcy levels have been associated with increased risk of mortality in patients with established coronary artery disease. Graft coronary disease is the major cause of morbidity and mortality in long-term survivors of heart transplantation. The tHcy has been found to be elevated in heart and kidney transplant patients, however, the etiologic factors have not been clearly delineated. METHODS: The study group consisted of 70 heart transplant recipients (56 males, 14 females, mean age 53+/-13 years [range 17 to 69 years]). The parameters evaluated were fasting tHcy level, cumulative cyclosporine (CyA) dose, cumulative prednisone dose, serum creatinine, and time from transplantation. RESULTS: The mean fasting tHcy level was 20.5+/-10.2 micromol/L (range 5.2 to 59.0 micromol/L). Sixty-one (87%) had fasting tHcy levels greater than the seventy-fifth percentile of the general population (>12.2 micromol/L in males, and >10.1 micromol/L in females). There was no difference in mean post-transplant tHcy level between patients with and without coronary artery disease before transplantation (21.0+/-11.4 vs. 19.3+/-6.7 micromol/L, p = NS). There were significant relationships between the tHcy level and the serum creatinine (r = 0.76, p<0.001), and cumulative exposure to CyA (r = 0.31, p<0.01). There were no significant relationships between tHcy levels and cumulative prednisone dose, or time from transplantation. CONCLUSIONS: Fasting tHcy levels are markedly elevated in the majority of patients following heart transplantation, and are correlated to serum creatinine. Further studies are needed to determine other etiologic factors of elevated tHcy following heart transplantation, and to examine the impact of elevated tHcy on clinical outcomes.

Adolescent↗
PubMed1999

Long-term blockade of nitric oxide synthesis in rats modulates coronary capillary network remodeling.

Long-term blockade of nitric oxide synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) induces cardiac perivascular fibrosis in rats. Its relationship to expression of angiogenic growth factors and capillary network remodeling is not understood. This study was designed to determine whether capillary proliferation and angiogenic growth factor regulation occur in response to L-NAME. Three groups of rats were studied: C, control; L1, L-NAME 13 mg/kg/day; L2, 130 mg/kg/day. One and eight weeks later the hearts were removed and subjected to morphometric analysis and analysis of gene expressions of molecules related to angiogenesis. Arterial hypertension was observed within 8 weeks in the L1 and L2 groups compared with control. After 1 week immunohistochemical assays demonstrated basic fibroblast growth factor (bFGF) in the arteriolar media. Northern blot analysis revealed increase in bFGF and transforming growth factor-beta (TGF-beta) mRNA during this period. At 8 weeks arteriolar medial thickening and perivascular fibrosis were seen microscopically in the L1 and L2 groups, which were accompanied by only a modest remodeling of capillary network due to increase in venular or intermediate capillary portions. Concomitantly immunoreactivity for vascular endothelial growth factor (VEGF) and TGF-beta were detected in perivascular area. These results suggest that (1) blockade of NO synthesis induces expression of angiogenic growth factors as well as vessel wall remodeling, and (2) TGF-beta may counteract angiogenic growth factors and limit subsequent alterations in capillary network remodeling.

Journal Article↗
PubMed1999

Isolation, characterization and immunolocalization of a novel, modular tomato arabinogalactan-protein corresponding to the LeAGP-1 gene.

Arabinogalactan-proteins (AGPs) are a family of hydroxy-proline-rich glycoproteins implicated to function in plant growth and development. This report focuses on a novel, modular AGP found in tomato, LeAGP-1, which was predicted by DNA cloning and herein verified at the protein level as a major AGP component. LeAGP-1 was isolated from tomato suspension-cultured cells and verified to be an AGP by precipitation with (beta-D-galactosyl)3 Yariv phenylglycoside and by amino acid composition analysis. Furthermore, LeAGP-1 was determined to correspond to LeAGP-1 clones based on three criteria: (1) amino acid composition identity, (2) amino acid sequence identity, and (3) specific immunoreactivity of glycosylated and deglycosylated LeAGP-1 with an antibody developed against the highly basic subdomain predicted from LeAGP-1 clones. The antibody was also used to immunolocalize LeAGP-1 in tomato to the cell surface of suspension-cultured cells, maturing metaxylem elements in young internodes and petioles, and stylar transmitting tissue cells. At the subcellular level, LeAGP-1 immunolocalized to the cell walls of these particular cells as well as to intercellular spaces between stylar transmitting tissue cells. LeAGP-1 now emerges as one of the most comprehensively studied AGPs in terms of (1) characterization at the genomic DNA, cDNA and protein levels, (2) known organ-specific and developmentally regulated mRNA expression patterns, (3) development of an antibody against a unique, peptide subdomain which specifically recognizes LeAGP-1 in its glycosylated and deglycosylated states, and (4) immunolocalization of a single, well-defined AGP molecule at the tissue and subcellular levels.

Amino Acid Sequence↗
PubMed1999

Yariv reagent treatment induces programmed cell death in Arabidopsis cell cultures and implicates arabinogalactan protein involvement.

Arabinogalactan proteins (AGPs) are a family of highly glycosylated, hydroxyproline-rich glycoproteins implicated in various aspects of plant growth and development. (beta-D-glucosyl)3 and (beta-D-galactosyl)3 Yariv phenylglycosides, commonly known as Yariv reagents, specifically bind AGPs in a non-covalent manner. Here (beta-D-galactosyl)3 Yariv reagent was added to Arabidopsis thaliana cell suspension cultures and determined to induce programmed cell death (PCD) by three criteria: (i) DNA fragmentation as detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) of DNA 3'-OH groups; (ii) inter- nucleosomal DNA fragmentation as visualized by genomic Southern blotting; and (iii) structural changes characteristic of PCD including cytoplasmic shrinkage and condensation, chromatin condensation and nuclear membrane blebbing. These findings implicate AGP involvement in PCD in plants, presumably by perturbation of AGPs located at the plasma membrane-cell wall interface.

Apoptosis↗
PubMed1999

Cardiovascular risk factors emerging in Chinese populations undergoing urbanization.

In this assessment of cardiovascular risk factors, we examined the association between dietary habits and blood pressure (BP) according to the World Health Organization (WHO) CARDIAC Study protocols in three Chinese populations aged 47-57 in Guangzhou prefecture (GZ group; 141 males, 158 females), Guiyang prefecture (GY group; 101 males, 103 females) and Taiwan (TW group; 102 males, 98 females). The same survey was repeated 10 yr later in the GY group to follow-up the past trends (MONALISA study). The observed systolic BP (SBP), diastolic BP (DBP), and body mass index (BMI), as well as the rates of hypertension, obesity and antihypertensive medication use were significantly higher in both genders in the TW group compared to the groups GZ and GY. There was no significant difference in SBP or DBP in either gender between groups GZ and GY. Blood analyses revealed that the levels of serum total cholesterol (T-CHO), and HbA1c, and the rates of hypercholesterolemia and high HbA1c were significantly higher in both genders in the TW than in the GZ and GY groups. No significant difference among the populations was observed in 24-h urinary sodium or magnesium excretion in either gender. In the combined total populations of men and women, however, significant positive correlations were observed between BMI and each of SBP, DBP, T-CHO, and glycohemoglobin in both genders. A food frequency analysis revealed significantly greater meat consumption and significantly less tea consumption and vegetable intake in the TW than in the GY and GZ groups. Both SBP and DBP have increased significantly over the past 10 yr in the GY group in both genders, and T-CHO as well as the rate of hypercholesterolemia increased over the same period in both genders. In conclusion, cardiovascular risk factors leading to hypertension, such as obesity, hypercholesterolemia and diabetes mellitus, are emerging in urbanized Taiwan and developing Guiyang due to the loss of traditional dietary habits.

Blood Pressure↗
PubMed1999

Improvement in the capillarity of the left ventricular wall of stroke-prone spontaneously hypertensive rats following angiotensin II receptor blockade.

The effect of the angiotensin II type 1 receptor blockade, candesartan cilexetil (TCV116), on the capillarity of the innermost region of the left ventricular subendocardium were studied in stroke-prone spontaneously hypertensive rats (SHRSP). The rats were fed for 32 days on chow that contained TCV116, the average dose being 0.96 mg/kg/day. Compared with values from control SHRSP, the systolic blood pressure, left ventricular weight and cross-sectional area of cardiomyocytes decreased. A significant increase in the total capillary density was coupled with a decrease of capillary domain areas in all capillary portions. The proportion of venular capillary portions, which was low in control SHRSP, increased significantly, suggesting neoangiogenesis of capillaries. The results indicate that AT1-receptor blockade caused regression of the hypertrophied cardiomyocytes and improved capillarity of the left ventricular wall.

Angiotensin Receptor Antagonists↗
PubMed1999

Study on pathogenic mechanism of emotions in traditional Chinese medicine--an observation of hydrogen peroxide releasing function of celiac macrophages in rats under stress state.

The hydrogen peroxide releasing function of macrophages in rats under the stress state was observed with the animal model of "excessive anger impairing the liver". The results showed that the volume of hydrogen peroxide released from the macrophages in rats was decreased, while the corticosterone level in plasma increased after stress. It indicates that stimulation of harmful emotions could cause inhibition of immunoreaction of the organism, which might be related to the enhancement in excitability of the hypothalamus-pituitary-adrenal axis and hypersecretion of glucocorticoid hormone.

Animals↗
PubMed1999

[Clinical significance of cardiac axis determination in prenatal echocardiographic diagnosis of fetal congenital heart disease].

OBJECTIVE: To investigate the clinical significance of cardiac axis determined by echocardiography in prenatal diagnosis of fetal congenital heart disease (CHD). METHODS: 518 high risk fetuses for CHD were and 90 normal fetuses were examined by echocardiography. Cardiac axis was measured on four-chamber view and fetal cardiac anatomical structure was examined in multiple views to determine CHD. RESULTS: The 35 fetuses with CHD diagnosed by prenatal echocardiography. There is significant difference of caidiac axis between CHD group (58.1 +/- 15.7 degree) and normal group (44.8 +/- 10.3 degree, P < 0.01). Sensitivity of CHD diagnosis using four-chamber view alone is 68.5%, it will be elevated to 91.4% by combination of four-chamber view and cardiac axis determination (P < 0.05). CONCLUSION: Cardiac axis play an important role in fetal echocardiographic screening for CHD and it should be measured routinely as part of the four-chamber view of the fetal heart. The normal range of fetal cardiac axis is 20 to 75 degree. If it was more than 75 degree, the CHD should be suspected.

Adult↗
PubMed1999

[Combined endobronchial and percutaneous radiotherapy after implanting the nitinol alloy endotrachial stent for advanced lung carcinoma].

OBJECTIVE: For the purpose to observe the effectiveness of treatment in late stage patients with bronchogenic carcinoma by implanting nitinol alloy endotrachial stent, combined with endobronchial 192 iridium (Ir) and percutaneous radiotherapy. METHODS: The nitiol alloy endotrachial stent was put into the site of airway stenosis through a special introducer under direct optical fibrobronchoscopy without the help of X-ray examination nor guided steel-line. 192 Ir was inserted to the site of tumor via bronchofiberscope for endobronchial irradiation combining with percutaneous radiotherapy alternately. RESULTS: In all 20 patients, 7 cases (35%) were completely cured and 11 cases (55%) showed partial recovery. The other 2 cases, no change or deteriorated. The 90% effective rate was significantly higher than 60% of control group (P < 0.05). CONCLUSIONS: Dyspnea of patients could be immediately relieved after endobronchial stent was inserted. Combined endobronchial and percutaneous radiotherapy obviously alleviated the obstruction caused by trachial or bronchial neoplasms. The results suggested the combined therapy led to much better objective therapeutic effect and symptomatic relief than single percutaneous radiotherapy.

Aged↗
PubMed1999

[Clinical significance of different mycobacterial antigens in diagnosis of tuberculosis].

OBJECTIVE: To evaluate the significance of different mycobacterial antigens in diagnosis of tuberculosis. METHODS: The sensitivity and specificity of 5 mycobacterial recombinant proteins in diagnosis of tuberculosis were observed by using ICT-TB card and the results of ICT-TB card were compared with PPD skin test and LAM. RESULTS: The sensitivities of ICT-TB card, LAM and PPD skin test in diagnosis of pulmonary tuberculosis were 55.9%, 52.6% and 75.0% respectively. There was statistically significant difference between the latter and the other two (P < 0.05). The specificities of ICT-TB card, LAM and PPD skin test in diagnosis of pulmonary tuberculosis were 87.6%, 62.9% and 68.9% respectively. There was statistically significant difference between the former and the other two. The clinical positive predictive value in diagnosis of pulmonary tuberculosis was 88.5%; the clinical negative predictive value was 53.8%. The positive reactions of ICT-TB in non-tuberculosis were caused mainly by antigens 4, 5, and if antigens 4, 5 were excluded, the specificity of ICT-TB card rose to 98.9%. CONCLUSIONS: The results suggested that measuring mycobacterial recombinant proteins was a useful supplementary tool for diagnosis of pulmonary tuberculosis.

Antigens, Bacterial↗
PubMed1999

[Study on relationship between two different syndromes and three soluble cytokine receptors in patients with rheumatoid arthritis].

OBJECTIVE: To study the relationship between two different Syndromes (Cold-Damp Syndrome and Damp-Heat Syndrome) and three soluble cytokine receptors (sCKR, soluble interleukin-2 receptor, sIL-2R, soluble interleukin-6 receptor, sIL-6R, soluble tumor necrosis factor receptor 1, sTNFR1) in rheumatoid arthritis (RA). METHODS: The serum levels of three soluble receptors were measured by ELISA in patients with RA. RESULTS: The serum levels of 3 sCKR were significantly elevated in RA patients compared to healthy controls and obviously lowered after treatment (P < 0.01). The level of sIL-2R was significantly higher in Cold-Damp Syndrome than that in Damp-Heat Syndrome (P < 0.01), but serum sTNFR1 was significantly higher in Damp-Heat Syndrome than that in Cold-Damp Syndrome, there was no obvious difference between sIL-6R of two Syndromes. CONCLUSION: The high serum sIL-2R and low sTNFR1 might be a criterion of Cold-Damp Syndrome, but the high sTNFR1 and low sIL-2R might be a criterion of Damp-Heat Syndrome, these criteria reflected some states of different functions in immune system in patients with RA.

Adolescent↗
PubMed1999

[A clinical study of mucosa-associated lymphoid tissue lymphoma].

OBJECTIVE: To have a better understanding of the clinical characteristics of mucosa-associated lymphoid tissue (MALT) lymphoma. METHODS: The clinical data of 24 patients with MALT lymphoma were analyzed. RESULTS: The patients were divided into two groups according to the initial location of the lymphoma in the gastrointestinal (GI) tract or not. Eighteen patients (75.0%) had GI involvement and six (25.0%) had involvement of other extranodal sites including salivary gland in three, lung in two and bladder in one. Among the 24 cases, 12 were in stage I, 7 in stage II and 5 in stage III-IV at the time of presentation. Fourteen cases underwent endoscopic biopsy and the pathologic diagnoses were in accordance with those of post-operative specimen in 11 but different in 3. Surgical resection was performed alone in 21 patients, with adjuvant chemotherapy in 7 and with adjuvant radiotherapy in 1. Three patients were treated with chemotherapy only. Results of survival analysis showed that the overall survival rate was 58.8% after 1 year, 35.3% after 3 years, 29.4% after 5 years and 5.9% after 10 years. No significant difference in clinical or biologic characteristics was observed between GI and non-GI patients (P > 0.05). The clinical stage and therapeutic measure had no significant relation with the prognosis. CONCLUSION: MALT lymphoma is an indolent disease that presents in localized extranodal location without any associated adverse prognostic factor in nearly all the patients and that these patients have a high response rate to treatment and a long survival.

Adult↗
PubMed1999

[Effects of epidermal growth factor, basic fibroblast growth factor and 5-fluorouracil on human retinal pigment epithelial wound closure in vitro].

OBJECTIVE: To study the effects of epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and 5-fluorouracil (5-Fu) on the cell migration and proliferation. METHODS: Phase-contrast microscopy, cell proliferation assay and wound -closure were used to study the process of cell proliferation and wound healing in a model of human retinal pigment epithelial (RPE) cell damage. RESULTS: It was found that EGF mainly stimulated proliferation and the migration of individual RPE cells from the wound edge, and induced cellular elongation, while bFGF mainly promoted proliferation and spread of the confluent monolayer into the wound defect, and induced enlargement and flattening of cells. But the effects of EGF, bFGF on wound closure were not very significant; 5-Fu inhibited the spread and proliferation of RPE cells, but had no effects on cell migration. CONCLUSIONS: EGF and bFGF have no significant effects on wound-healing, perhaps their effects on cell morphology are very important in cell transformation in proliferative vitreoretinopathy (PVR), and 5-Fu can only be a subsidiary drug to prevent PVR.

Cell Division↗
PubMed1999

[Expression of transforming growth factor alpha and its relationship with HBV infection in hepatocellular carcinomas].

OBJECTIVE: To assess the expression of TGF alpha in hepatocellular carcinoma and its relationship with HBV infection. METHODS: Using in situ hybridization and streptavidin-peroxidase immunohistochemistry to detect TGF alpha mRNA, TGF alpha protein and HBV DNA in 53 cases of HCC and 14 cases of controls. RESULTS: Positive rates of TGF alpha mRNA and TGF alpha protein in carcinoma tissue were 30.2% and 73.6% respectively, which were higher than in normal controls (P < 0.05). The expression of TGF alpha mRNA and TGF alpha protein was increased significantly in dysplastic liver cells (DLC) locating aside from the tumor tissue in comparing with those of non-dysplastic liver cells (NDLC) (P < 0.05). Positive rates of HBV DNA in carcinoma tissue and paratumorous liver tissue were 56.6% and 60.4% respectively, which were higher than in the normal controls (P < 0.001). Positive rate of HBV DNA in the nuclei of tumor tissues, tissue of the dysplastic areas and non-dysplastic areas was lowering down successively (P < 0.05). There was a significant relationship between expression of TGF alpha mRNA and TGF alpha protein in the carcinoma tissues and HBV DNA in the tumorous and its surrounding tissues respectively. CONCLUSIONS: Expression of TGF alpha in carcinoma tissues was closely associated with the existence of HBV DNA and TGF alpha may participate in the early stage of liver carcinogenesis. The increased expression of HBV DNA in nuclei may serve as an important morphology marker in distinguishing carcinoma from DLC and NDLC.

Carcinoma, Hepatocellular↗
PubMed1999

[The identification of 5 new serotypes of Bacillus thuringiensis from soil in China].

Five new strains of Bacillus thuringiensis(Bt) from soil in China were classified. 5 new H-serotypes: H42, H43, H56, H60 and H62 were identified. There were some distinction in the morphology, biochemical reaction and toxicity against species of insect. Five new Bt subspecies were identified as follows: Strain YGd22-03 Bacillus thuringiensis subsp. jinghongiensis, H42; Strain KK31-01 Bacillus thuringiensis subsp. guiyangiensis, H43; Strain SCg04-02 B. thuringiensis subsp. rongseni, H56; Strain NXP15-04 B. thuringiensis subsp. pingluonsis, H60; Strain HZ39-04 B. thuringiensis subsp. zhaodongensis, H62.

Animals↗
PubMed1999

[New coleopterancidai strains of Bacillus thuringiensis and production of coleopterancide].

Two coleopterancidal strains of Bacillus thuringiensis, YM-03 and SHQ11-10, were isolated from soil in China. H-Serotype of YM-03 was H8a8b, and H-Serotype of SHQ11-10 has not been identified. Both of them produced flat bipyramid-like crystals which consisted of 68-70 kD and 65 kD protein respectively. Bioassay indicated that these two Bt strains were very active on the larva of Leptinotarsa decemlineata and Plagioder aversicolora. They grew prosperously in fermentation. Powder of YM-03 product was high effect against colorado potato beetle in the field experiment.

Animals↗
PubMed1999

[Determination of rare-earth impurities in ultra-highly pure Er2O3 and Ho2O3 by [HEH(HEP)] extraction chromatography-atomic emission spectrometry].

This article applied [HEH(HEP)] (2-ethyhexyldrogen-2-ethylhexyl phosphonate) extraction chromatography to separate 14 rare earth impurities from ultra-highly pure Er2O3 and Ho2O3, and then the impurities were determined by atomic emission spectrometry. The average percentage recovery for each element is in the range of 70%-140%. The relative standard deviations of the determination are +/- 3.3%-2.2%. This method can be applied to the determination of the trace amounts of rare eath impurities in Er2O3 and Ho2O3 with a purity of 99.9999%-99.99999%.

English Abstract↗