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Biomedical subjects

M Zhao

Publications and source records attributed to M Zhao.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Immunohistochemical study of vascular endothelial growth factor, relative receptors and ligands in vascular endothelial cells of cerebral arteriovenous malformation].

OBJECTIVE: To study morphologically the formation, growth and rupture of cerebral arterivenous malformation (CAVM). METHOD: By means of immunostaining we studied vascular endothelial growth factor (VEGF), Tie-1, Tie-2, Ang-1, Ang-2 in endothelial cells (EC) of CAVM (30 specimens) and control cortical vessel (7 specimens) in the temporal lobe. RESULTS: The expression of VEGF in EC of CAVM was -884, +1,819, + +424 and in controls -445, +29, + +10. The expression of Tie-1 in EC of CAVM was -2,252, +626, + +12 and in controls -421, +88, + +6. The expression of Tie-2 in EC of CAVM was -683, +1,908, + 8 and in controls -444, +64, + +7. The expression of Ang-1 in EC of CAVM was -2,215, +209, + +41 and in controls -487, +41, + +9. The expression of Ang-2 in EC of CAVM was -956, +2,099, + +135 and in controls -475, , + +9. CONCLUSION: Up-regulated VEGF in part of brain and Tie-2, Ang-2 high expression in EC of some vessels may be one of major factors for CAVM formation growth, and rupture in the embryonic period.

Angiopoietin-1↗
PubMed2001

[Effects of Streptococcus sanguis on blood composition, blood pressure and cardiac dysfunction in rabbis].

OBJECTIVE: To investigate effect of streptococcus sanguis on blood cell and cardiopulmonary changes. METHODS: 133-79 strains of streptococcus sanguis (aggregation positive) were infused intravenously into rabbits. Before and 5, 10, 20, 30, 45, 60 min after infuse platelets count, leukocytes count, blood pressure and ECG were measured. RESULTS: After infused intravenously, both platelets and leukocytes count decreased remarkably (P < 0.01, n = 12). The ECG showed ST segment depression (> 0.06 mV). Diphasic blood pressure occurred (first hypertensive then hypotensive). CONCLUSIONS: Streptococcus sanguis 133-79 strains in circulation system might cause myocardia ischemia, blood pressure changes, peripheral circulation platelets and leukocytes decrease remarkably.

Animals↗
PubMed2001

Effect of ipratropium bromide on airway and pulmonary muscarinic receptors in a rat model of chronic obstructive pulmonary disease.

OBJECTIVE: To observe the level of muscarinic receptors in airway and lung tissues, and the effect of inhaled ipratropium bromide on these receptors in a rat model of chronic obstructive pulmonary disease (COPD). METHODS: This model was developed by exposure of rats to 250 ppm SO2 gas, 5 h/d, 5 d/wk, for a period of 7 wk. The COPD rats inhaled 0.025% aerosolized iratropium bromide for 20 min, 2 times daily, in an airtight chamber. Muscarinic receptors in airway and lung tissues of normal rats, ipratropium bromide-treated COPD rats and the recovering COPD rats were measured by the radio-ligand binding assay. RESULTS: Airway/lung pathology and pulmonary function tests showed that chronic SO2 exposure caused pathophysiologic changes similar to those observed in human COPD. The density (0.038 +/- 0.011, pmol/mg protein) and affinity (Kd, 23 +/- 11 pmol/L) of muscarinic receptors in airway and lung tissues of COPD rats were not changed compared with those of normal control rats (0.030 +/- 0.008 and 29 +/- 19, respectively, P > 0.05). Densities of the muscarinic receptors were not changed after inhalation of ipratropium bromide for 5 days, but increased significantly after inhalation for 30 days, as compared with those of the untreated COPD rats. The muscarinic receptors returned the normal levels at day 6 after cessation of ipratropium bromide treatment. There were no differences among different groups of rats in equilibrium dissociation constants (Kd). CONCLUSION: A rat model of COPD with pathophysiologic changes similar to the human counterpart was developed using chronic SO2 exposure. There was no significant change in the number and function of muscarinic receptors in airway and lung tissues of the COPD rats, but upregulation of the muscarinic receptors was observed after long-term inhalation of ipratropium bromide.

Animals↗
PubMed2001

Study on action of acupuncture on ventromedial nucleus of hypothalamus in obese rats.

Effects of acupuncture on the spontaneous discharge of nerve cells and levels of monoamine neurotransmitters in ventromedial nucleus of hypothalamus (VMH) of the obese rats were investigated. Results indicated that the levels of tyrosine (Tyr) and dopamine (DA) were lowered, the levels of 5-hydroxytryptamine (5-HT) and 5-hydoxyindole acetic acid (5-HIAA) increased, and the frequency of the spontaneous discharge of nerve cells in VMH lowered in the obese rat group as compared with the normal group. When acupuncture obtained the effect of weight reduction, the frequency of spontaneous discharges of nerve cells in VMH were markedly increased, and the levels of Tyr, DA and tryptamine (Typ) and 5-HT/5-HIAA ratio elevated, and the 5-HT level lowered. It is suggested that the virtuous regulative action of acupuncture on VMH might be one of the key factors in acupuncture for weight reduction.

Acupuncture↗
PubMed2001

[A clinical and pathological analysis of 41 patients with anti-glomerular basement membrane antibody related diseases].

OBJECTIVE: To investigate the clinical and pathological characteristics of anti-glomerular basement membrane (GBM) antibody associated diseases with different clinical patterns. METHODS: The clinical and pathological data of 41 patients with anti-GBM antibody associated diseases, screened in our institute in recent six years, were retrospectively analyzed. RESULTS: 22 of the 41 patients presented as Goodpasture syndrome, 2 of them having normal renal function. 32 of the 41 patients had anti-GBM antibody positive only (single positive). 31 of the 32 single positive patients were male with an average age of (26.8 +/- 9.7) years. The remaining 9 patients were both anti-GBM antibody and antineutrophil cytoplasmic antibody (ANCA) positive (double positive); 7 of the 9 were female with an average age of (44.5 +/- 19.6) years. There was significant difference in gender and age between the single and double positive groups (P < 0.05). 30 of the 32 patients with renal biopsy had crescentic glomerulonephritis and the remaining two with normal renal function had mild mesangial proliferative glomerulonephritis only. 24 of the 30 (80%) crescentic glomerulonephritis patients had all glomeruli affected by crescents with severe glomerular capillary loop and Bowman's capsule damage. With immunofluorescence examination, 16 of the 23 cases had typical IgG and C(3) linear deposition along glomerular capillary walls, but the remaining 7 had fine granular IgG and/or C(3) deposition. In a few cases, granular deposition was found even in mesangium. There was no correlation between the immunofluorescence patterns and the severity of glomerular damage (P > 0.05). All patients had anemia, hematuria and proteinuria, 7 of the 41 cases presented as nephrotic syndrome. After intensive immunosuppressive therapy, only four patients, including the two patients with normal renal functions, achieved remission, the remaining patients either were in renal replacement therapy or died. CONCLUSIONS: Anti-GBM antibody associated diseases are not rare in China. Single positive patients are mainly young male, while double positive patients are mainly middle-aged female. Most of the patients with anti-GBM antibody associated diseases have crescentic glomerulonephritis (rapidly progressive glomerulonephritis, RPGN) with a bad prognosis. However, not all the patients have typical linear deposition of IgG and C(3) along glomerular capillary walls. Only a few non-oliguric patients with normal renal function or mild renal damage may achieve remission.

Adolescent↗
PubMed2001

[Clinico-pathological features and possible pathogenesis of rifampicin-induced acute renal failure].

OBJECTIVE: To explore the clinico-pathological features and possible pathogenesis of rifampicin-associated acute renal failure (ARF). METHODS: The clinico-pathological features of 4 patients with Rifampicin-associated ARF were analyzed. Rifampicin-dependent antibody in the patient's serum was detected with Coomb's test. RESULTS: 4 cases with rifampicin-associated ARF was distinguished from 202 in-patients with ARF in 5 years(1.98%). Most of them had infection before the occurrence of ARF. Clinical features were characterized by fever, fatigue and gastro-intestinal symptoms after taking rifampicin (especially when it was reused). Oliguria or anuria developed suddenly. Laboratory data showed hemolytic anemia, thrombocytopenia and decline of renal function. Some also had impaired liver function. Renal biopsy revealed acute tubular necrosis in 3 cases and acute interstitial nephritis in 1 case. Serum rifampicin-dependent antibody was positive in all the cases. CONCLUSION: Rifampicin-associated ARF is not rare clinically, especially in those rifampicin re-exposure patients. Renal function should be closely monitored in susceptible patients. Detection of serum rifampicin-dependent antibody may be helpful to distinguish this group of ARF patients.

Acute Kidney Injury↗
PubMed2001

[Expression of fused luxAB gene of bacterial luciferase in liver carcinoma cells].

OBJECTIVE: This work was done to look into the expression of fused luxAB gene of bacterial luciferase as a reporter gene in liver carcinoma cells. METHODS: The mammalian expression vector pcDNA3-luxAB gene, constructed by the fusion of luxA and luxB genes, were amplified in the polymerase chain reaction (PCR) directed site mutagenesis from the vibrio harveyi 1600 strain and inserted into the plasmid of pcDNA3. This analysis was to confirm the fused luxAB gene and the positive clones obtained by the G418 resistant stable selection and transfected by lipofectin, when they were confirmed by the PCR. The growth curve of cell population and luminescence of bacterial luciferase was obtained through MTT and bioluminescence, respectively. RESULTS: The fused luxAB gene, being a monocistron, completely agreed with the design. No significant difference in the growth curves of cell population was observed between the transfected cells and untransfected ones. The recombinant plasmid was likely to be expressed in a stable fashion in the BEL7402 cell. Meanwhile, the maximum cellular level in terms of vitro bioluminescent strength reached the point of (8.71 +/- 1.21) mV/40 micrograms protein. CONCLUSION: Bacterial luciferase luxAB gene may become the first choice as a new, sensitive and non-invasive reporter gene in the research on liver cancer cells.

Animals↗
PubMed2001

[Preliminary study of effect of antisense hsc70 effect on the stability of mutant p53 protein].

OBJECTIVE: To investigate the effect of antisense hsc70 RNA on the stability of mutant p53 protein. METHODS: Using DNA recombination technique, retroviral recombinant expressing antisense hsc70 RNA was constructed and transfected into MCF7/Adr cells. After the existence of foreign DNA had been identified by the polymerase chain reaction (PCR) method, the protein level of hsc70 was detected by Western blot. The half-life of mutant p53 was detected by p53 stability assay. RESULTS: With the stable expressive transfectant cell strains obtained through G418 selection, the foreign DNA in transfectant cells were confirmed by PCR method and the repression rate of hsc70 protein was 42%. The half-life of mutant p53 in MAc70 cell was 10 hours which was significantly lower than the control cells. CONCLUSION: Antisense hsc70 RNA is able to lower the hsc70 protein level and significantly increase the instability of mutant p53 protein in MCF7/Adr human breast cancer cells.

Blotting, Western↗
PubMed2001

[Effect of various cavity design, lining and restorative materials on the fracture resistance of teeth].

OBJECTIVE: To evaluate the influence of various cavity designs, lining and restorative materials on fracture resistance of teeth in vitro. METHODS: Factorial design with three factors and various levels was used. 36 extracted human maxillary premalors were prepared for occlusal cavity, MO cavity and MOD cavity. Various base material and restorations were used. All teeth were thermocycled and mounted for testing and then were loaded until fracture. The results were analyzed by a three-way ANOVA. Fracture patterns were observed at the same time. RESULTS: There was significant difference in fracture resistance among various cavity designs and restorations. The fracture patterns were different. CONCLUSIONS: The different classes of cavities and various restorations have significantly influence upon fracture resistance of teeth. There are interactions between cavities and restorations.

Dental Cavity Lining↗
PubMed2001

[Pharmacokinetical study of safflor yellow on rat acute model of blood stasis syndrome].

OBJECTIVE: To study the pharmacokinetical character of safflor yellow in rat acute model of blood stasis syndrome. METHODS: The rat acute model of blood stasis syndrome was made by i.p. adrenalin (0.07 ml/kg) and the stimulation of ice-water. At the time of 5, 10, 30, 60, 120, 180, 320, 480 min, the concentration of safflor yellow in the serum after i.v. safflor yellow (37.08 ml/kg) was determined. RESULTS: The concentration-time date of safflor yellow in rat acute model of blood stasis syndrome was shown to fit a double-compartment open model, t1/2 alpha = 1.43 min, t1/2 beta = 95.65 min, AUC = 49,632.90 micrograms.min/ml; while the concentration-time data of safflor yellow in normal rat was shown to fit a single-compartment open model, t1/2 alpha = 66.27 min, AUC = 42,267 micrograms.min/ml. CONCLUSION: The metabolism of safflor yellow was evidently later in rat acute model of blood stasis syndrome than in normal rat.

Acute Disease↗
PubMed2001

[A study of different intracellular signal transduction pathways on phagocytosis of fibronectin by retinal pigment epithelial cells].

OBJECTIVE: To determine the phagocytosis of fibronectin (FN) by retinal pigment epithelial (RPE) cells and its related intracellular signal transduction pathways. METHODS: Fluorescent latex beads were coated by FN and then incubated with RPE cells at 37C for 3 hours. Phagocytosis was quantified by a flow cytometric assay. Experiments were also performed in the presence of inhibitors of various intracellular signaling pathways [tyrosine kinase (TK), phosphatidylinositol 3-kinase (PI 3-K), protein kinase C (PKC)]. RESULTS: FN-coated beads produced significantly increase in the phagocytic index (P < 0.05) when compared to the uncoated control. The PKC inhibitors, phorbol 12-myristate 13-acetate (PMA, 100 nmol/L) or calphostin C (400 nmol/L), non-specifically increased the phagocytosis of both FN-coated (P < 0.01) and uncoated beads (P < 0.01). Inhibitors of TK (genistein, 100 microgram/ml) and PI 3-K (wortmannin, 5 micromol/L), significantly inhibited FN phagocytosis (P < 0.001) but did not affect the uncoated control. While a combination of different inhibitors (genistein plus wortmannin, genistein plus PMA, wortmannin plus PMA) was used, the results showed that genistein or wortmannin can counteract the effect of PMA, and that genistein plus wortmannin have an additive inhibitory effect. CONCLUSIONS: Our results suggest that the FN phagocytosis by RPE cells appear to be regulated, at least in part, by some signal transduction pathways. The knowledge of the signaling pathways that mediate FN phagocytosis by RPE cells may provide novel therapeutic targets for molecular pharmacology of proliferative RPE disorders such as proliferative vitreoretinopathy.

Androstadienes↗
PubMed2001

[Immunorelated pancytopenia].

OBJECTIVE: A report of a group of patients with pancytopenia which might be related to abnormal immunity. METHODS: The clinical and laboratory features of 29 patients with positive bone marrow mononuclear cell (BMMNC) Coombs tests were analyzed. RESULTS: Most of these cases were pancytopenia with normal or decreased bone marrow cellularities and increased normoblasts. They were all found to have negative results of conventional hemolysis tests and hematopoietic nutrient determination and had no evidence of malignant clonal hematopoiesis. However, all of them showed positive BMMNC-Coombs test and good response to corticosteroids. CONCLUSION: Immunorelated pancytopenia might be caused by abnormal immunity (especially autoantibody) mediated destruction or abnormal function of blood cells. It is beneficial to differentiate immunorelated pancytopenia from aplastic anemia or myelodysplastic syndromes.

Adolescent↗
PubMed2001

[Sequential intensified immunosuppressive therapy combining with hematopoietic growth factors in the treatment of severe aplastic anemia].

OBJECTIVE: To explore more effective regimen for reducing early mortality of severe aplastic anemia (SAA) and improving therapeutic effectiveness. METHODS: Antilymphocyte globulin/antithymocyte globulin (ALG/ATG) and cyclosporine A (CsA) (sequential intensified immunosuppressive therapy, SIIST), with or without hematopoietic growth factors (HGFs) were administered to 73 SAA patients in a prospective randomized clinical trial to test the effectiveness of the addition of HGFs for the patients. RESULTS: The response rate of SIIST with HGFs group was significantly higher than that of SIIST alone group (89.2% vs 63.9%), with lower rates of early infection (24.3% vs 55.3%) and mortality (4.0% vs 16.7%), shorter duration of cytopenia and blood transfusion dependence and faster recovery of bone marrow hematopoiesis. The addition of HGFs to SIIST was tolerated well in all patients. There was no difference in the treatment outcome of the two groups with GM-CSF plus Epo or G-CSF plus Epo. CONCLUSION: The use of HGFs in combination with SIIST could reduce early infection and mortality rates and, therefore, improve the response rates in SAA patients.

Adolescent↗
PubMed2001

[Study on the transformation from myelodysplastic syndromes into acute leukemias].

OBJECTIVE: To study the patterns of transformation from myelodysplastic syndromes (MDS) into acute leukemias (AL). METHODS: Leukemic transformation of MDS patients was dynamically followed up and the clinical manifestations, peripheral blood and bone marrow pictures, karyotypes, immunophenotypes, response to treatment and prognosis of post MDS acute leukemia (postMDS-AL) were observed. RESULTS: During the past eight year and seven months, 21 (13.91%) of 151 MDS patients progressed to overt leukemia with a median interval of 5 (1 - 21) months. There were no significant differences among the rates of leukemia from RA, RAEB and RAEB-t groups. The transformation was developed either gradually or rapidly. There were five parameters related to the leukemic transformation: under 40 years of age, pancytopenia, more than 0.15 blasts in bone marrow, at least two types of abnormal karyotype and combined chemotherapy. All of the 21 post MDS-AL were acute myeloid leukemia (AML); and most of them were M(2), M(4) and M(5). Two (9.52%) post MDS-AML developed extramedullary infiltration. Leukopenia was found in 47.62% of patients. Two third of the patients, whose bone marrows were generally hypercellular, showed neutropenias. After evolving into AML, 8 (47.06%) patients developed abnormal karyotypes. High expression of immature myeloid antigens, including CD(33) (49.83 +/- 24.50)%, CD(13) (36.38 +/- 33.84)%, monocytic antigen CD(14) (38.50 +/- 24.60)%, and stem cell marker CD(34) (34.67 +/- 30.59)% were found on bone marrow mononuclear cells of post MDS-AML cases. In some cases, lymphoid antigens, such as CD(5), CD(7), CD(9) and CD(19) were coexisted with myeloid antigens. A low complete remission rate (31.25%) and short survival duration with median survival of 6 (1 - 28) months were found in patients with post MDS-AML treated by induction therapy. CONCLUSION: MDS was at high risk of evolving into AML, either gradually or rapidly. Patients with post MDS-AML had specific biologic features and worse prognoses.

Acute Disease↗
PubMed2001

[Relationship between the symptom of xerostomia and non-stimulated salivary flow rates in patients with burning mouth syndrome].

OBJECTIVE: Many patients with burning mouth syndrome (BMS) complain of xerostomia, but the consistent relationship between the symptom of xerostomia and non-stimulated salivary flow rates remains unclear. This study tried to investigate the variety of non-stimulated salivary flow rates in patients with BMS. METHODS: The non-stimulated salivary flow rates of 52 BMS patients and 37 healthy controls were recorded. RESULTS: The non-stimulated salivary flow rates were low in the group of BMS patients, but there is no statistical difference when compared with that of the normal individuals. There was also no significant difference in non-stimulated salivary flow rates among theses three subtypes of BMS patients. Further, no significant difference of non-stimulated salivary flow rates was observed in patients with and without xerostomia. CONCLUSION: The non-stimulated salivary flow rate may be not associated with the symptom of xerostomia in patients with BMS.

Burning Mouth Syndrome↗
PubMed2001

[Phospholipase activities of Candida albicans isolates from oral pre-malignant lesions and oral cancers].

OBJECTIVE: The aim of this study is to compare activities of phospholipase of Candida albicans isolates from oral cavities of two groups of patients, including oral pre-malignant lesions and oral cancers. METHODS: A total of 55 isolates, including oral pre-malignant lesions (21), oral cancers (15), and normal health control (19), were studied using the precipitate zone assay on the egg yolk agar. RESULTS: No significant difference was found in phospholipase activities between these isolates from normal controls and oral pre-malignant lesions, while the activities of phospholipase of isolates from oral cancers were higher than those of the normal controls. CONCLUSION: Candida albicans may play different roles in different manners in these two closely related diseases.

Candida albicans↗