Biomedical subjects

Xiu-mei Zhang

Publications and source records attributed to Xiu-mei Zhang.

5 recordsLinked to original sources

PubMed2006

[Protective effects of hydroxyethylpuerarin against brain astrocytes injury induced by hydrogen peroxide].

AIM: To study the protective effects of hydroxyethylpuerarin against the injury of astrocytes induced by hydrogen peroxide (H2O2). METHODS: Experiments were performed with cells from passage 4. Plasma membrane integrity was measured by lactate dehydrogenase (LDH) release. The occurrence of apoptosis was measured by flow cytometry. The glutamate uptake of astrocytes was studied with [3H]-glutamate incorporation. Intracellular superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were assessed by automatic biochemistry analyzer. RESULTS: Compared with H2O2 injured group, the occurrence of apoptosis, levels of LDH release and intracellular MDA of astrocytes reduced in hydroxyethylpuerarin pre-treated groups, but the glutamate uptake and intracellular SOD activity of astrocytes increased. CONCLUSION: Hydroxyethylpuerarin could reduce the occurrence of apoptosis and improve neurotrophic function of astrocytes, which may be related with its antioxidant effects during oxidative stress.

Animals↗

PubMed2006

[Effect of baicalin on HSP70 expression of hippocampal neurons in focal brain ischemia-reperfusion injury rats].

AIM: To investigate the effect of baicalin on the hippocampal neuronal apoptosis and the expression of HSP70 in rats with focal brain ischemia-reperfusion injury. METHODS: One hundred and twenty male Wistar rats were randomly divided into six groups:sham operated group, ischemia-reperfusion group, nimodipine group and three baicalin groups,to which baicalin was administered at doses of 50, 100 and 200 mg x kg(-1), separately. The models of focal brain ischemia-reperfusion injury induced by middle cerebral artery occlusion (MCAO) were used in this study. HE stain was used to observe the pathological changes. Flow cytometry (FCM) was used for determination of neuronal apoptosis. HSP70 protein expression of the neurons was detected with immunohistochemistry. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of the mRNA level of HSP70. RESULTS: Baicalin can significantly relieve the pathological changes and inhibit apoptosis in hippocampus CA1 area, and at the same time increase the expression of HSP70 and HSP70 mRNA. CONCLUSION: Baicalin can relieve brain damage induced by focal brain ischemia-reperfusion in rats, which may be related to inhibiting the process of the neuronal apoptosis. The mechanism of antiapoptosis effect of baicalin may be related to the promotion of transcription of HSP70 mRNA and increasing the expression of the protein.

Animals↗

PubMed2006

[Research on dissolved nitrogen and phosphorus loading model based on GIS].

In order to research the origin of nonpoint source pollution dissolved nitrogen (DN) and dissolved phosphorus (DP), some artificial rainfall experiments was made at Guanting Reservoir. The experimental data show that the correlation between transporting rate of DN (DP) and the runoff is very good, with the average correlation coefficient 0.9978 and 0.9889 for DN and DP respectively. Therefore, a new load model of DN(DP) is put forward. While applying it, we studied the spatial distribution of DN (DP) pollution load according to the digital elevation model (DEM) and the information obtained from land use map and soil map. Its results show that DN mainly originated from irrigable land first, mound and hill second.

Geographic Information Systems↗

PubMed2005

Protective effects of hydroxyethylpuerarin on cultured bovine cerebral microvascular endothelial cells damaged by hydrogen peroxide.

AIM: To observe the damages induced by hydrogen peroxide in cultured bovine cerebral microvascular endothelial cells (BCMEC) and evaluate the protective effects of hydroxyethylpuerarin on hydrogen peroxide-injured BCMEC. METHODS: BCMEC were cultured and transferred into modified Eagle medium (MEM). The viability of cells was detected by MTT assay. Cell injury was determined by lactate dehydrogenase (LDH) activity in the extracellular medium. Flow cytometry was employed to observe the occurrence of apoptosis. Morphologic changes of cells were visualized under phase contrast and electron microscopes. RESULTS: Hydrogen peroxide (200 micromol x L(-1) for 4 hours) inhibited the viability of cultured BCMEC and stimulated LDH release. Hydrogen peroxide (100 micromol x L(-1) for 4 hours) induced the occurrence of apoptosis. Hydroxyethylpuerarin was shown to increase the survival rate and decrease the activity of LDH of BCMEC damaged by hydrogen peroxide. Hydroxyethylpuerarin was also found to protect BCMEC against apoptosis induced by hydrogen peroxide. CONCLUSION: Hydrogen peroxide induces BCMEC injury either by apoptosis or through necrosis. Hydroxyethylpuerarin protects BCMEC against hydrogen peroxide-induced injury in a concentration-dependent manner. Its antioxidant effects might be involved as the mechanism protection.

Animals↗

PubMed2004

[The clinical application of 18F-fluorodeoxyglucose coincidence imaging in lymphoma].

OBJECTIVE: To investigate clinical value of (18)F-fluorodeoxyglucose ((18)F-FDG) coincidence imaging (SPECT/PET) in diagnosis and treatment of lymphoma. METHODS: (18)F-FDG metabolic imaging was performed in eighteen patients NHL before and after treatment using a Vertex(Plus) EPIC MCD/AC from ADAC Company. The findings of (18)F-FDG metabolic images were analyzed in qualitative and semi-quantitative ways. (18)F-FDG images were compared with synchronous routine images such as ultrasonography and CT. RESULTS: Thirty studies were performed in 18 patients with NHL in this study. There were 21 true positives, 6 true negatives, 2 false positives and 1 false negative. The accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 90.0%, 95.5%, 75.0%, 91.3%, and 85.7%, respectively. (18)F-FDG imaging led to a change of 16.7% in clinical staging, and 46.7% in management. The PPV and NPV of recurrence detected by (18)F-FDG SPECT/PET were 100% and 80.0%, while these of CT were 50.0% and 25.0% after therapy. Four of five patients with negative entered clinical complete remission (CR), whereas all the 11 patients with abnormal (18)F-FDG uptake relapsed or reprogressed. Progression-free survival (PFS) with negative (18)F-FDG was 16 - 47 months (median: 28.7 months) and PFS with positive was 3 - 46 months (median: 8.3 months). CONCLUSION: SPECT/PET (18)F-FDG metabolic imaging plays an important role in clinical diagnosis and treatment of NHL.

Adult↗