Search PubMed⌕ Search

Biomedical subjects

M Zhang

Publications and source records attributed to M Zhang.

At least 865 records · Page 48Linked to original sources
PubMed1995

[Effect of Cladonia alpestris on Trichomonas vaginalis in vitro].

In this paper, an experimental research is reported on the effect of water extract of Cladonia alpestris and S-(-) usnic acid on Trichomonas vaginalis in vitro. The results showed that both the water extract of Cladonia alpestris and S-(-)usnic acid exhibited a strong effect against Trichomonas vaginalis in vitro. As the time of action of the agents was prolonged, the mortality of Trichomonas vaginalis increased. For S-(-) usnic acid, 0.4 mg/ml was the lowest effective concentration against Trichomonas vaginalis in vitro. No remarkable differences were found in the effect of the S-(-)usnic acid and metronidazole at concentrations of 0.4 mg/ml and 0.6 mg/ml.

Animals↗
PubMed1995

Endotoxin-induced liver injury and changes in the levels of plasma tumor necrosis factor-alpha and interleukin-6 in rabbits.

ELISA was employed to detect changes in plasma TNF-alpha and IL-6 level in rabbits having endotoxin-induced generalized Shwartzman reaction. Liver injury was assessed by the increase of serum ALT and hepatic histopathologic changes. The results showed that plasma TNF-alpha and IL-6 levels increased remarkably 12h after intravenous injection of endotoxin twice at a 24h interval, and these changes corresponded with the degree of liver injury. Coinjection of dexamethasone and endotoxin partly prevented the elevation of TNF-alpha and IL-6 levels and reduced liver injury. These results indicated that TNF-alpha and IL-6 were involved in endotoxin-induced liver injury.

Animals↗
PubMed1995

[Morphine blocked the exitatory amino acid mediated membrane current in ambigual motoneurons of the rat].

Excitatory postsynaptic potentials (EPSPs) and responses of neurons in the compact formation of the neucleus ambiguus (AMBc) to pressure-ejected or bath-applied test substances were recorded intracellularly from sagittal slices of Sprague-Dawley rat medulla containing subnucleus centralis of solitary complex (NTSc), AMBc and solitarioambigual pathway. In 5 cells, recorded spontaneous EPSPs could be blocked by morphine (3-5 pmol) to AMBc. Electrical stimulation of NTSc evoked EPSPs in AMBc neurons, the amplitude of which were decreased to 71.1 +/- 6.2% (P < 0.001) with the addition to morphine. The morphine effect could be abolished by bath-applied naloxone (50 nmol/L). The amplitude of membrane depolarization induced by pressure-ejected N-methyl-D-aspartate (NMDA, 0.5-1.0 pmol), acetylcholine (3 pmol) and quisqualate (0.1-0.5 pmol) to NTSc could also be decreased by bath-applied morphine (10 mumol/L) respectively to 38.1 +/- 5.7% (P < 0.001), 32.8 +/- 5.5% (P < 0.01) and 29.6 +/- 7.1% (P < 0.05). The above results suggest that morphine is capable of block by NMDA, ACh and non-NMDA receptors, increaseing the M-current and decreasing the permeability of Na+ and Ca2+.

Animals↗
PubMed1995

[Clinical application of luteinizing hormone releasing hormone agonist and its impact on bone metabolism].

OBJECTIVES: To evaluate the efficacy of luteinizing hormone releasing hormone agonist (LHRH-A) in the treatment of endometriosis (Em), uterine leiomyoma and adenomyosis, and its impact on bone metabolism. METHODS: Twenty patients, Em 13 (stage II4, III7, IV2), leiomyoma 4 and adenomyosis 3, were selected to receive LHRH-A 200 micrograms intramuscular daily for 3 months. Clinical and ultrasound features serum follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), osteocalcin (BGP) concentrations were compared before and at the end of treatment. Furthermore, 24-hour urinary calcium (Ca), phosphate (P) excretions and bone mineral density (BMD) of radius and lumbar spine measured by single photon absorptiometry (SPA) and dual energy X-ray absorptiometry (DEXA) were also analysed before and at the end of treatment. Patients were followed-up 3-19 months after discontinuation of the drug. RESULTS: At the end of treatment dysmenorrhea disappeared in all 15 cases. Pelvic tenderness and induration improved in 18, endometrioma shrinked in 13 cases. Mean uterine volume of 7 patients with leiomyoma or adenomyosis was reduced by 35% from the basal volume. Serum LH, E2 levels were suppressed significantly (P < 0.05), mean E2 concentration declined from 459.5 +/- 292.0 to 160.3 +/- 110.7 pmol/L (P < 0.001). No significant change was found in serum BGP, urinary Ca, P, and BMD of radius and lumbar spine at the end of therapy, The only side effect was mild not flushes and sweating during treatment. After stopping the drug, 17 patients resumed menses within 2 months. Dysmenorrhea and pelvic mass recurred in 6 months with less severity. One became pregnant in 3 months. CONCLUSIONS: LHRH-A administration is effective in the treatment of Em, leiomyoma and adenomyosis. No significant adverse effect was shown on bone metabolism at the end of 3-month therapy.

Adult↗
PubMed1995

[Inhibitory effect of heparin on glomerular mesangial cell].

The pure mesangial cells (MsC) were isolated from the culture of rat glomeruli. After identification, they were divided into heparin-treatment group and control group. It was found that heparin profoundly inhibited the growth of MsC with 75.9% inhibitory rate by means of direct counting MsC. MTT method proved that the inhibitory effect of heparin on MsC was dose-dependent. Electronmicroscopic observation revealed dilated endoplasmic reticulum and Golgi vesicles, more secondary lysosomes, prominent myelin figures and decreased microfilaments in the cytoplasm of the MsC exposed to heparin. Immunocytochemical studies showed that the amounts of FN and LM in the cytoplasm of MsC decreased after heparin treatment. Immunocytochemical investigation also confirmed that heparin could inhibit the expression of nuclear oncogene c-fos and c-jun in the MsC stimulated by PMA. The significance and possible mechanism of inhibitory effect of heparin on MsC were discussed.

Animals↗
PubMed1995

Effects of tetrandrine on rabbit platelet aggregation and platelet activating factor generation.

AIM: To study the effects of tetrandrine (Tet) on platelet aggregation and platelet activating factor (PAF) generation in rabbit platelet-rich plasma (PRP). METHODS: The aggregation rate of platelets induced by calcimycin (Cal) and PAF and the inhibition rate of Tet on platelet aggregation were measured. The amount of PAF in PRP stimulated with Cal and treated with Tet was also measured. RESULTS: Cal 1-8 mumol.L(-1) and PAF 9.5-190.5 pmol.L(-1) induced platelet aggregation. At the final concentrations of 4-64 mumol.L(-1), Tet inhibited the aggregation induced by Cal 4 mumol.L(-1) and PAF 142.9 pmol.L-1. The IC50 (95% confidence limits) were 8.6 (6.0-12.2) mumol.L-1 for Cal and 14.0 (6.4-30.4) mumol.L(-1) for PAF. In the PRP aggregation by Cal, there was a marked increase in PAF content. Tet dependented the release of PAF from platelets by Cal in a concentration-dependent manner, with IC50 of 21 (8-54) mumol.L(-1). CONCLUSION: The inhibition effect of Tet on platelet aggregation might be concerned with the reduction of endogenous PAF generation.

Alkaloids↗
PubMed1995

Improved targeting of radiolabeled streptavidin in tumors pretargeted with biotinylated monoclonal antibodies through an avidin chase.

UNLABELLED: Radiolabeled streptavidin can be accumulated in tumors pretargeted with biotinylated anti-tumor antibodies. However, circulating biotinylated antibody and endogenous biotin may interfere with the tumor targeting of streptavidin. To reduce biotinylated antibody concentration in the blood, we injected avidin before streptavidin administration. The effects of avidin administration on the biodistribution and tumor targeting of radiolabeled streptavidin were examined. METHODS: Biotinylated anti-human colon cancer monoclonal antibody (MAb) MLS128 was injected intravenously into nude mice bearing human colon cancer xenografts for pretargeting. After intraperitoneal injection of avidin, radioiodinated streptavidin was administered and its biodistribution and tumor accumulation was investigated. RESULTS: Radioiodinated streptavidin specifically localized in the tumor pretargeted with biotinylated antibody. Avidin preadministration accelerated the tumor uptake and blood clearance of radioiodinated streptavidin. The tumor-to-blood radioactivity ratio at 6 and 24 hr after radiolabeled streptavidin injection were 1.23 +/- 0.29 and 3.04 +/- 0.86, respectively, in mice with avidin chase (mean +/- s.d., n = 7), and 0.82 +/- 0.17 and 2.29 +/- 0.29, respectively, in those without chase (mean +/- s.d., n = 7). CONCLUSION: Localization of radiolabeled streptavidin in tumors pretargeted with biotinylated MAb could be improved by avidin chase. This approach may be useful for tumor radioimmunoimaging and radioimmunotherapy.

Animals↗
PubMed1995

[A study on relationship between balance of serum lipoprotein and the phlegm damp-blood stasis syndrome differentiation of coronary heart diseases].

75 patients were divided into A,B and C group. The LDL-C was 2.97 +/- 0.67, 4.05 +/- 0.38 and 5.25 +/- 0.98 mmol/L respectively (P > 0.01); but comparing group A or B with the normal group (D), it had no significant difference (P > 0.05). An abnormal coronary arteriography (CAG) was found in the group A in 62.1% and the group B in 57.6% (P > 0.05), while the group C in 84.6% (P < 0.01). There was unusual serum lipoprotein electrophoretogram (SLPG) in group A 75.9%, group B 84.8% and group C 100%, but it had no change in group D (P < 0.001). Five types of Syndrome Differentiation about the Phlegm damp and blood stasis (PDBS) could be found in the group A,B and C. The incidence (51.5%-55.2%) and abnormality of the SLPG (66.7%-92.5%) and CAG (68.8%-100%) of PDBS type were the highest among them. 82.7% CHD patient's clinical comprehensive diagnosis was in accordance with the SLPG and that of the CAG were 64.0%. As to the abnormal SLPG, the sensitivity and rate of coincidence of CAG was 91.7% and 69.3% (P < 0.05-0.01) respectively. The Syndrome Differentiation of PDBS was valuable in differentiating CHD. The SLPG is a good criterion for the study of CHD in TCM.

Adult↗
PubMed1995

[Assessment by three-dimensional CT of pleural indentation or invasion by peripheral lung cancer].

We evaluated the effectiveness of three-dimensional (3D) CT for pleural indentation or invasion by peripheral lung cancer adjacent to pleura. Pleural indentation was shown in three of nine cases on conventional CT, and six cases were demonstrated three-dimensionally. 3D-CT was superior to conventional CT in demonstrating pleural indentation. Pleural invasion could not be assessed on 3D-CT because the pleura adjacent to the tumor was not visualized.

Humans↗
PubMed1995

[Observation on dynamics of circulating antigen from patients with cysticercosis before and after treatment].

The dynamics of circulating antigen (CAg) level in sera form patients with cysticercosis before and after albendazole treatment were detected by using monoclonal antibody-based double antibody sandwich ELISA (McAb-ELISA). The results indicate that after the patients with cysticercosis had been treated for one, two and three treatment courses, the levels of CAg in sera decreased with the increase in the number of treatment courses, their average OD value dropped from 0.499 before treatment to 0.291, 0.073 and 0.051 after treatment, respectively, and the corresponding negative conversion rates of CAg detection were 20.0%, 57.9% and 87.5%, respectively. Sera from eight patients who had received three courses of albendazole treatment were detected for CAg and CAb before and after treatment. The results indicate that the CAb level dropped rather slowly after three courses of treatment as compared to CAg level. It is concluded that detecting circulating antigen might be used as a promising method for evaluating the drug efficacy.

Albendazole↗
PubMed1995

[Construction and expression of the gene CD4V1V2-PE40, coding for a molecular targeted protein against AIDS].

We here replaced the cell-binding domain in Pseudomonas exotoxin A (PE) with HIV-binding portion of CD4V1V2 molecule and constructed a chimeric gene CD4V1V2-PE40, which can be expressed in E. coli. The hybrid protein displays targeting toxicity toward cells infected by HIV and thus represents a promising novel therapeutic agent for the treatment of AIDS.

ADP Ribose Transferases↗
PubMed1995

Cloning and expression of the gene coding for IL-2(60)-PE40, a molecular targeted protein.

It has recently been shown that chimeric toxin composed of IL2 fused tp PE40, a mutant form of Pseudomonas Exotoxin A devoid of its native cell recognition and binding domain was cytotoxic to IL2 receptor bearing cells. We here amplified the gene IL-2 (60), which codes for the N-terminal 1-60 amino acids of human IL-2 by PCR. After that, we fused it to PE40 and the new chimeric protein IL-2(60)-PE40 was expressed in E. coli. SDS-PAGE revealed that IL-2(60)-PE40 chimeric protein accounts for more than 18% of total cell proteins. As the region IL-2 binds with its receptor was defined in the N-terminal residues 8-54 of IL-2, such fusion proteins will have the same activity with IL-2-PE40. Following primary purification, IL-2(60)-PE40 was shown to be very toxic to IL-2 receptor-positive cells but non measurable effect on the cells lacking IL-2 receptors. Such a structure has not been reported by now. The fusion protein is useful for suppressing the immune response in cases of rejection of allografts and organ transplants and as therapeutic agents for the treatment of IL-2 receptor related diseases such as autoimmune disease, ATL (adult T-cell leukemia), et al.

Animals↗
PubMed1995

[Effects of verapamil on left ventricular diastolic dysfunction].

To assess the effects of verapamil on left ventricular relaxation and filling dynamics in patients with left ventricular diastolic dysfunction (LVDD), Doppler echocardiography (DE) and cardiac catheterization (Cath) were simultaneously performed in 30 cases with LVDD. The left ventricular filling and relaxation indices were measured with DE and Cath respectively, before and after intravenous injection of verapamil. The result showed that after verapamil injection all left ventricular filling measured with DE were significantly improved in all cases, while left ventricular relaxation indices showed significant improvement only in patients with hypertrophic cardiomyopathy and hypertensive heart disease but no changes in patients with old myocardial infarction. There were no significant correlations between left ventricular filling and relaxation indices. It is concluded that the major mechanism of left ventricular filling improvement induced by verapamil is the reduction of left ventricular afterload and verapamil has different therapeutic effects on LVDD with different etiology.

Adolescent↗
PubMed1995

[Biotherapy of advanced cancer by infusion of in vitro activated autolymphocytes].

Autolymphocyte biotherapy is an adoptive cellular therapy based upon the infusion of autologous lymphocytes that have been activated in vitro by anti-CD3 monoclonal antibody and depleted of suppressor T cells by cimetidine, indomethacin and low dose of gamma irradiation. The patients also receive oral cimetidine to block suppressor T cell activity in vivo. Sixty five patients received 217 autolymphocyte infusions and toxicity was minimal with transient fever and chill accompanying 18 infusions. The efficacy of treatment in patients received more than 3 infusions were evaluated. In 37 evaluable patients, the response rate (CR+PR) was 24% (9/37). As the side reactions are mild, the treatment can be done on an outpatient basis.

Adolescent↗