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Objective: To investigate the expression of ATP-Binding Cassette Proteins including P-gp (P-glycoprotein), MRP1 (multidrug resistance associated protein 1) and BCRP (breast cancer resistance protein) in hepatocellular carcinoma and its relationship with pathological features. Methods: The expression of P-gp/MDR1 (multidrug resistance gene 1), MRP1 and BCRP in hepatocellular carcinoma was examined by RT-PCR and immunohistochemistry in 34 cases of hepatocellular carcinoma and 19 cases of paraneoplastic hepatic tissues. Results: The expression of MDR1, MRP1 and BCRP mRNA (messenger ribonucleic acid) was 1.15±0.24, 0.64±0.33, and 1.07±0.32 in hepatocellular carcinoma and 0.36±0.14, 0.19±0.06, and 0.31±0.09 in paraneoplastic hepatic tissues. The expression of MDR1, MRP1 and BCRP mRNA was 1.38±0.26, 0.73±0.35, and 1.34±0.21 in poorly differentiated hepatocellular carcinoma and 0.74±0.32, 0.30±0.11, and 0.45±0.13 in well differentiated hepatic tissues. The immunohistochemical positive substance was detected in the plasma membrane and cytoplasm. The positive rates of P-gp, MRP1 and BCRP were 82.35%, 58.82%, and 79.41% in hepatocellular carcinoma and 42.11%, 26.32%, and 36.84% in paraneoplastic hepatic tissues, respectively. The positive rates of P-gp, MRP1 and BCRP were 100.00%, 81.25%, and 100.00% in poorly differentiated hepatocellular carcinoma and 66.67%, 38.89%, and 61.11% in well differentiated hepatic tissues. The expression of three indicies in hepatocellular carcinoma was higher than that in paraneoplastic hepatic tissues (P<0.05). The expression of P-gp/MDR1, MRP1 and BCRP in poorly differentiated hepatocellular carcinoma was higher than that in well differentiated hepatic tissues (P<0.05). No correlation was found among the three indices. Conclusion: Intrinsic multidrug resistance exsists in hepatocellular carcinoma, with various mechanisms. The multidrug resistance of HCC (hepatic cell carcinoma) is related to P-gp/MDR1, MRP1 and BCRP. MRP1 and BCRP may be targets for reversing multidrug resistance.
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Objective The patients with lethal irradiation after sucessful hematopoietic stem cells transplan-tation had blood recovery, but did not avoid to died of multiple organ failure(MOF). To overcome the block, the article investigated mechanisms of mesenchymal stem cells (MSCs) protecting lethal radiated mice from multiple organ failure after haploid bone marrow cells transplantation. Method BALB/c mice irradiated with 8Gy60COγ-rays were randomly divided into two groups: MSCs group, infused MSCs labeled with cm-DiI and bone marrow monocytes of CB6F1 mice; Control group, only infused bone marrow monocytes; normal group, mice were infused cm-DiI marked MSCs without irradiation. The distribution of MSCs and the serous densities of Il-2, Il-10 and TNF-α in the recipients were observed after transplantation. Results MSCs collected in the bone marrow and the intes-tine in normal group at 15 d,in MSCs group MSCs enriched the different organs at 3,15 and 30 d. MSCs regulated down the secretion of IL-2 and TNF-α,and up the IL-10 density. Conclusions MSCs protected mice from multiple organ failure through above effects and may be open a new treatment strategy on acute radiation syndrome by stem cells.
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Objective To investigate the mechanism of mesenchymal stem cells in enhancing the effects of haploid matched bone marrow cells transplantation in mice with acute radiation syndrome(ARS).Methods The survival of mice infused with difierent levels of MSCs and bone marrow cells after 8 Gy TBl were examined.BALB/c female mice irradiated with 8 Gy of 60Co γ-rays were randomly divided into two groups,MSCs group,infused with MSCs of female CB6F1 mice labeled with cm-DiI and bone marrow monocytes of male CB6F1,Control group,only infused with bone marrow monocytes.Peripheral blood counts,T-lymphocyte subpopulation of peripheral blood cells,the sry-gene chimerism of bone marrow of the receiptors,the distribution of MSCs in the receiptors,the occurrence time of cGVHD,pathologic variety of medulla were observed.Resuits MSCs improved the survival of mice after 8 TBI,but 1.5×108/kg of MSCs increased the mortality of irradiated mice.In comparison with the control group,leukocytes and plastocytes recovered rapidly in MSCs group.Megacaryocytes in sternum marrows grew fastly in MSC group.The percent of CD3 and CD4 positive cells in the MSCs group were hisher than those in control post-transplantation.The sry-gene chimerism of bone marrow of the receiptors was higher in the MSCs group than that in the control at 30 d.The MSCs were distributed in intestine,thymus,bone marrow,liver,heart of the receiptors at 30 d.The cGVHD occurrence was 30 d later in MSCs group than that of the control.Conclusions MSCs could improve stem cell engraftment,enhance T-lymphocyte and plastocytes recevery,delay occurrence of cGVHD,repair injured organs and increase survivals.It is indicated that MSCs can enhance the treatment effects of haploid hematopoietic stem cells transplant for ARS.
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The teaching of Neurology is a emphasis and difficulty in clinical teaching.In the present article,we summarized some experiences of how to improve the teaching quality of Neurology.
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BACKGROUND: Cell apoptosis is one of the important pathological changes in ischemic-reperfusion (IR) injury. As the key factor involved in cell apoptosis regulation, interleukin (IL)-iβ converting enzyme, when activated, leads to cell apoptosis via protein degradation.OBJECTIVE: To investigate the relationship between the expression of IL-1β converting enzyme and cell apoptosis in cerebral IR injury and explore the role of this enzyme in post-ischemia cell apoptosis.DESIGN: Randomized controlled experiment.MATERIALS: The experiment was performed at the Center of Neuroscience of the Third Military Medical University between March 1996 and December 2000. Totally 64 adult healthy Wistar rats were randomized into two groups, namely IR group (n=56) and sham operation group (n=8). In IR group, the rats were subjected to four vessel occlusion to mimic whole brain IR injury, and reperfusion was carried out after 30 minutes of ischemia for 3, 6, 12, 24, 48, 72 hours and 7 days, respectively (8 rats at each time point). Only separation but not occlusion of the bilateral common carotid artery was performed in sham operation group.METHODS: Four rats were randomly selected from IR group at each time point and 4 from the sham operation group for immunohistochemical study and in situ hybridization, with the other 4 rats for in situ end-labeling assay.MAIN OUTCOME MEASURES: Protein and mRNA expression of ILlβ converting enzyme and neural cell apoptosis in the brain.RESULTS: Totally 64 rats were used in this study and all data were statistically analyzed. In the sham operation group, IL-1β converting enzyme protein and mRNA were expressed in small amount in most of the normal brain tissues, and their expressions were also detected in the neurons and small glial cells in IR group localized mainly in the cerebral cortex, cerebellum Purkinje's cells, hippocampal and subcortical white matters. The expression of IL-lβ converting enzyme began to increase at IR 12 hours, reaching the peak level at 48-72 hours followed by declination since 7 days after the operation. Cell apoptosis occurred 12 hours after IR (49.4±6.8) /section and peaked at 72 hours (228.6±29.8)/section, showing significant correlation with the temporal expression of IL-1β converting enzyme protein and mRNA (r=0.89, 0.68, P ＜ 0.05).CONCLUSIONS: Expressions of IL-1β converting enzyme protein and mRNA increased after IR in close correlation with post-ischemia cell apoptosis, and their temporal expression pattern supports the presumption that IL-1β converting enzyme is an important factor in cell apoptosis.Apoptosis is mostly likely to occur in the cerebral cortex, hippocampus and basal ganglion in IR injury, where IL-1β converting enzyme is highly expressed, further demonstrating that post-ischemia expression of IL-1β converting enzyme might be involved in cell apoptosis regulation.
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Objective To observe the change of nitric oxide(NO) content and explore its cell source following brain ischemic injury. Methods We established the model of transient global brain ischemia/reperfusion (IR) in rat. The concentration of NO and its cell source were investigated by detection of NO content, NDP histochemical staining, double label technique of immunofluorescence and stereological analysis after brain ischemia. Results (1)The content of NO increased at 12 h and peaked on days 1～3 after IR. The content of NO decreased gradually on the 5th day after IR. (2)The density of NDP positive cells increased and peaked on the 1st day after IR. The positive cells distributed mainly in the temporal cortex, hippocampus and periventricular zone after IR. The positive cells were found to reduce gradually or disappear on the 14th day after IR. (3)Few NDP positive and GFAP immunofluorescence positive cells were found to coexist at the early period of IR(1～3 d). The percentage of coexisting cells was 10%～15%. Conclusion The content of NO increases at the early period after ischemic brain injury. The main cell type to produce NO is neuron.
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Objective: Executive dysfunction is a typical characteristic of vascular cognitive impairment(VCI),with subcortical ischemia as its pathological basis.The aim of this study was to investigate the characteristics of event-related potential of visual-spatial working memory based on ischemic white matter lesions,and offer more electrophysiological evidence for the evaluation of VCI.Methods: We included in this study 24 patients with ischemic white matter lesions(13 mild and 11 severe cases) and 12 elderly healthy controls,and induced event-related potentials(ERP) of visual-spatial working memory from the delayed matching-to-sample task in all the participants.Results: Three waves were identified: N330,P420 and late negative component. On the two-ball-load,the N330 amplitude in the middle frontal,right frontal and occipital lobe was significantly smaller in the mild and severe lesion groups(P
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Objective:To examine the effect of psychological and physiological stress on monoamine in extracellular fluid of hippocampus under simulated high-altitude hypobaric hypoxia.Methods:Psychological and physiological stress were made by the way of communication box.The hypoxia disposal was that the rats were put hypobaric chamber at a simulated altitude of 6000 meters for 24 hours.We compared the effect of stress in different sorts and intensity on the contents of norepinephrine(NE),dopamine(DA),5-hydroxytryptamine(5-HT)in extracellular fluid of hippocampus.The extracellular fluid of hippocampus of rat was collected by push-pull perfusion;we determined the contents of monoamine in it by high performance liquid chromatography with electrichemical detection(HPLC-ECD).Results:(1)The simulated high-altitude hypobaric hypoxia reduced the content of NE in extracellular fluid of hippocampus(813.8?196.1/1209.2?282.0,P
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Objective To investigate the effect of lipid ultrasonic microbubble on the cellular absorption rate of antiparallel phosphorothioate triplex-forming oligonucleotide(TFO) and the expression of the tissue factor(TF) in endothelial cells.Methods The GT21-apsTFO,specific to the gene sequence of the shearing stress response element,was synthesized and the lipid ultrasonic microbubble carrying TFO was constructed.The ECV304 cells were divided into 4 groups:control group(SSRE),received shear stress only for 6h;TFO+ ultrasonic irradiation group(TFO+U),treated with 60?l TFO in final concentration of 0.2?mol/L and ultrasonic irradiation for 30s simultaneously;TFO-lipid microbubble group(TFO-M),treated with 60?l lipid microbubble loaded with TFO in final concentration of 0.2?mol/L;and TFO-lipid microbubble + ultrasonic irradiation group(TFO-M+U),treated with 60?l lipid microbubble loaded with TFO(final concentration was 0.2?mol/L) and ultrasonic irradiation for 30s simultaneously.Cells in the last 3 groups were treated with shear stress for 6h with pressure of 1.2Pa 24h after transfection.The fluorescent microscope was used to observe the cellular absorption rate of TFO.The immunofluorescence method and RT-PCR were employed to determine the protein and mRNA expressions of TF.Results The transfection efficiency of the TFO was higher in TFO-M+U group(38.83%?6.52%) than in TFO-M group(9.50%?2.88%) and TFO+U group(12.66%?3.01%,P
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Objective To investigate features and significance of the temporal and spatial expression of GFAP and Vimentin in olfactory system of Xenopus from metamorphosis to adult. Methods Xenopus tadpoles from stage 48 to 63 were made into serial sections(20??m)by Cryostat,each contains the nose,the olfactory nerve,and the olfactory bulb.The immunohistochemistry staining was done on these sections by anti-GFAP and anti-Vimentin,and then observed by fluorescence microscope.Results Olfactory nerve showed very strongly GFAP-IR staining during metamophosis of Xenopus.In the olfactory bulb,GFAP-IR positive staining was found only in the nerve layer,but not in glomeruli.By contrast,Vimentin-IR decorated radial glia in the olfactory bulb but faintly stained the olfactory nerve.Conclusion GFAP and Vimentin present complementary staining patterns,GFAP is expressed in the peripheral olfactory system while vimentin is expressed in the central part of olfactory system.