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In order to promote the integration between disciplines, the convergence between basic course and clinical teaching, increasing students ability including the active learning and life-long learning ability, finding problem and solving problem ability, teamwork spirit and so on. After nearly 3 years preparation, Hebei Medical University successfully carried out the PBL teaching in Seven-year Clinical Medicine Science. Combining with the teaching activities, formative assessment was carried out, and PBL teaching website was established. The reform has already achieved initial results, got good responds from teachers and students. Through the study, it has been confirmed that the PBL teaching method in Hebei Medical University is effective and worthy to reference.
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Objective To study the effect of ethonal on the dopaminergic system by analyzing the altered expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the brain of ethanol-treated rats. Methods Sixty Wistar rats were selected and divided into control group and ethanol-treated group, 30 per group, the ethanol-treated rats were treated with 20% ethanol for 6 months. Immunohistochemistry, flow cytometry and Western blotting were used to analyze the altered expression of TH and DAT in the DA energic system in different brain regions of the ethanol treated rats. Results 1. Immunohistochemistry showed the mean gray value of TH in substantia nigra(SN)-ventrotegmental area (VTA), caudae putamen (Cpu) and nucleus accumbens (NACC), DAT in Cpu and NACC of the ethanol were smaller than those in control (P<0.05). 2. Flow cytometry showed the expression of TH in middle brain of the ethanol-treated rats increased significantly compared with the control(P<0.05). 3. Western blotting showed the ratio of IA of TH/β-actin and DAT/β-actin in different brain regions of the ethanol-treated rats were larger than those in control(P<0.05).Conclusion Ethanol treatment increases the expression of TH and DAT in rat brain.
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Objective The present study is to investigate IL-24 gene(Ad5F35-hIL-24) effect on the topoisommeraseⅡα(topoⅡα) and Caspase-3 expression in glioma cell line U251. Methods After transfected the U251 glioma cells with the Ad5F35-hIL-24, the methyl thiazolyl tetrazolium (MTT) was used to analyse the inhibition rate of Ad5F35-hIL-24 on the cells. Hoechst 33258 fluorescent staining and flow cytometric assay were used to detect apoptosis. The immunohistochemistry assay was used to detect topoⅡα expression, and Western blotting was applied to detect the protein expression of topoⅡα and caspase-3. Transwell experiment was used to test the invasiveness of the cells. Results It was found that the Ad5F35-hIL-24 could inhibit U251 cell proliferation and induce apoptosis in a dose dependent manner compared with the control groups. It showed that Ad5F35-hIL-24 could inhibit topoⅡα expression reveled by immunohistochemistry and Westeren blotting, while it increased caspase-3 protein expression. The Transwell experiment showed that the Ad5F35-hIL-24 could reduce the invasiveness of the U251 glioma cells.Conclusion The exogenous IL-24 gene can inhibit the cell proliferation and induce apoptosis of U251 glioma cells. The topoⅡα and Caspase-3 are the important molecular targets of the IL-24 gene. These results may give support for the IL-24 gene usage in clinical treatment for glioma patients.
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BACKGROUND: There are few reports addressing the differentiation of bone marrow mesenchymal stem cells (BMSCs) into neurons, and the uncertainties mainly focused on the differentiated neurons had neuron morphology, but did not have neuron function. OBJECTIVE: To investigate the feasibility of rat bone marrow mesenchyma stem cells (BMSCs) differentiation into neuron-like cells and glial-like cells under rat hippocampal neuron's conditional medium. METHODS: Rat BMSCs at passage 5 were divided into 4 groups. The medium of hippocampal neurons and glial cells was added in the conditioned medium group. The Dulbecco's modified Eagle's medium containing bFGF was added in the basic fibroblast growth factor (bFGF) group. The serum-free medium containing Neurobasal and B27 was added in the serum-free medium group. The DMEM supplemented with fetal bovine serum was added in the negative control group. 12 and 24 hours following induction, neuron specific enolase (NSE), microtubule-associated protein-2 (MAP-2) and glial fibrillary acidic protein (GFAP) were detected using immunocytochemical staining in each group. NSE, MAP-2 and GFAP expression was determined using Western-blot assay. RESULTS AND CONCLUSION: 12 and 24 hours following induction, BMSCs were positive for MAP-2, GFAP and NSE in the conditioned medium, bFGF and serum-free medium groups, but negative in the negative control group. Compared with the negative control group, MAP-2 expression was significantly enhanced in the conditioned medium, bFGF and serum-free medium groups 24 hours following induction (P < 0.05), and the increased range was significantly greater in the conditioned medium group compared with other two groups (P < 0.05). No significant difference in NSE and GFAP expression was detected in the conditioned medium, bFGF and serum-free medium groups. Results suggested that hippocampal neuron conditioned medium can in vitro induce the differentiation of rat BMSCs into neuron-like cells and glial cell-like cells. Compared with the bFGF medium and serum-free medium, positive rate was greatest in the hippocampal neuron conditioned medium-induced neurons and glial cells.
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Objective To observe the relationship between the change of endothelin-1 (ET-1), nitric oxide synthase(NOS) content and cerebral vasospasm after experiment Sprague-Dawley rat subarachnoid hemorrhage (SAH). Methods SD rat got the tail artery blood and followed prone positioning in a stereotaxic apparatus, injected autologous arterial blood or saline into cisterna magna,2 d later injected in the same way. For basilar artery (BA),internal carotid artery(ICA) ,and middle cerebral artery(MCA) diameter measurements,gelatin-india ink vascular casted,the blood ET-1 and NOS content were detected by immunoradiology or colorimetry measurement. Results Microangiography in SAH showed extensive macroscopic filling deficit,the diameter of MCA,ICA and BA ((169.33 ±8.67)mm, (227.33 ± 14.25) mm, (226.33 ±5.99) mm respectively) were shorter than those in control group((259.5 ±7.48)mm,(228.17 ±8.09)mm,(254. 67 ±8.48)mm respectively) (all P<0.05). Neuronal function score of 7d(9.45 ±1.77) was higher than control group(0.60 ±0.49) (P<0.05). Content of ET-1 and NOS in blood after SAH 7 d were(231.25 ± 19.45)g/L,(198.50 ±9.52) × 103U/L) ,(72.99 ±5.83)g/L, (230.76 ±17.06) × 103U/L),for sham group,there was significant differences (P<0.05). Conclusion Experiment rat double-hemorrhage method from tail artery can makes experimental subarachnoid hemorrhage model,neurological functional score is increased, neuronal function score is associated with diameter of MCA and ET-1 content.
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Objective To observe the morphological changes of pancreatic tissue of thoracic duct ligated rats in fine and ultrastructural levels, and to determine whether lymph block animal model can affect pancreatic islet amyloid polypeptide(PIAP)deposit in rat pancreas. Methods At the 6th month after the operation, some pancreatic tissue sections of 16-month-old experimental rats were embedded in paraffin wax and stained with HE and Congo red;immunohistochemical staining was performed on some frozen sections, which were then observed with light microscope;transmission electron microscope (TEM) specimen preparation and observation were performed on other samples. Results HE and Congo red stained sections showed that the pancreatic glandular lobule space was widened, with significant connective tissue hyperplasia, and fat accumulation when the islet was stained indistinctly or vermeil and tissue space was broadened. The sections with immunohistochemical staining displayed the pancreatic islet as well as the tissues around it were stained into dark brown being positive with PIAP antigen. TEM observation showed the pancreatic glandular interlobule space was widened, while blood vessels and enlarged lymphatic vessels were visible;within widened pancreatic islet interstitial space, a great quantity of lipid droplets and some collagen fibril structures could be seen.Conclusion The ligation of thoracic duct can contribute to pancreatic lymph draining block, lymphagiectasis, connective tissue space and interstitial space widening, fat accumulation, and PIAP deposit in rat pancreas. These structural changes may affect the function of pancreatic islets.
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Objective To study serotonin transporters(SERT) in postmortem human brains of Parkinson's disease(PD).Methods Immunoautoradiography was used to show SERT distribution in postmortem PD brains.ResultsIn comparison with healthy group,SERT decreased in dorsal raphe nucleus,substantia nigra and striatum in PD brains.Quantitative analysis showed that 25.9%、31.1%、27.2% and 24.7% of labeling intensity of SERT decreased in putamen,caudate nucleus,substantia nigra and ventrotegmental area as compared with corresponding control respectively.Among the four regions studied of dorsal raphe nucleus,SERT labeling intensity significantly decreased by 38.9%,37.3%,16.5% and 37.0% of corresponding control respectively in ventral part,dorsal part,caudal part and interfascicular part.Median raphe nucleus did not show the decreased SERT labeling.ConclusionDecreased SERT expression in three regions of postmortem PD brains indicates that a dysfunction of serotonergic raphe system may contribute to the etiology of Parkinson's disease.
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Objective To observe the expression of OBR and NPY in mouse hypothalamus.Methods In mouse hypothalamus,the location and coexpression of OBR and NPY were observed with immunohistochemistry and double immunohistochemistry.Results OBR positive cells distributed as clump in hypothalamus ME,ARC and VMN,having obscure boundary.OBR positive cells were also present in choroid plexus,brain ependymal layer cell and vascular endothelial cells.In hypothalamus ARC,NPY positive neurons were present with bright red color in cell plasma.The NPY positive neurons were found as round or ellipse,having many neurites.NPY positive fibers were present in ME.In double immunohistochemistry result,the coexpression of OBR and NPY showed black color,because that OBR positive cells showed brown purple or dark purple granula near the NPY positive neurons.Conclusion OBR distributed in ME,ARC,VMN of mouse hypothalamus,choroid plexus,brain ependymal layer cells and vascular endothelial cells.Meanwhile NPY also distributed in ME,ARC,cerebral cortex and hippocampus and so on.Moreover the coexpression of OBR and NPY was present in mouse hypothalamus ARC.
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Objective To study the altered expression of dopamine transporter (DAT) in substantia nigra and striatum in postmortem human brain of Parkinson’s disease (PD). Methods Immunoautoradiography was used to reveal DAT distribution in postmortem human brain. Results Strongly labeling signal of DAT was mainly found in the substantia nigra, the putamen and the caudate nucleus in controls. In contrast, it was drastically reduced in the putmen and the dorsolateral caudate nuclus in PD brains, but the ventromedial part of the caudate nucleus showed a significant sparing adjacent to the border of the lateral ventricle. In the substantia nigra, the ventral and the lateral parts of the substantia nigra showed an obvious decreasing of DAT and the reducing degree of DAT labeling signals in those regions is smaller than that in the putamen and the caudate nucleus. Quantitative analysis revealed that 90.9% and 66.7% of the labeling intensity of DAT were decreased in the putamen and the caudate nucleus as comparing with the corresponding controls respectively (P
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Objective Immunoreactive intensity of dopamine transporter(DAT)was quantitatively analyzed in the different regions of postmortem human brain in order to provide evidence in selecting an appropriate reference region for neuroimaging in measurement of the altered DAT.Methods The brain tissue blocks taken from 8 male cadavers were paraffin-embedded and sectioned,and immunoautoradiography was used to display the difference of DAT immunoreactive intensity in the substantia nigra,putamen and caudate nucleus,cingulate cortex,frontal cortex,occipital cortex and cerebellar cortex.Results The highest DAT density was found mainly in the substantia nigra,caudate nucleus and putamen,while the lowest density was only seen in cerebellar cortex.Quantitative analysis revealed that the intensity of DAT immunoreactivity(DAT-IR)in cerebellar cortex was respectively 1/3.50,1/3.72,1/1.28 of that in frontal cortex,cingulate cortex and occipital cortex,and it was only 1/8.33,1/11.67,1/8.56 that of substantia nigra,caudate nucleus and putamen.Conclusions The cerebellar cortex has the lowest DAT as compared to other examined brain regions,and it can be used for a reference region in neuroimaging to detect altered DAT.
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Objective To explore the effect of androgen on learning and memory ability and neurons in hippocampal CA1 region in senescence accelerated mouse prone strain/8(SAMP8).Methods Thirty 7-month-old male SAMP8 were randomly divided into sham-operation control group,castrated group and androgen replacement therapy after castration group.The dose of testosterone undecanoate(TU) was 37.4mg/(kg?15d).The capability of learning and memory was observed 45 days later through the Morris water maze(MWM) test and the change of neurons in hippocampal CA1 region was detected and analyzed by HE staining,immunohistochemal method and computer pathological image analysis system.Results 1.In the MWM test,the escape latency of castrated group were significantly prolonged(P0.05).2.With HE staining,neurons in hippocampal CA1 region of castrated group were found with diffused vacuolar degeneration,and sparse and disordered cellular arranpement.The cell nucleuses were karyochrome and karyopycnosis.The number and optical density of A? immune positive neurons were markedly higher than those of other groups(P
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The microvasculature of the rabbit right ventricle was studied by the method of vascular corrosion cast and scanning electron microscopy. In the endocardium could be seen thin and sparse capillary network i. e. subendothelial capillary network formed by the branches of the arterioles passing through myocardium. In the myocardium, arteriole and its branches distributed in certain area. Sphincters could be seen in the beginning of the arterioles. Capillaries of the papillary muscle in right ventricle were parallel to muscle bundle and were thinner and sparser than those of the papillary muscle in left ventricle. Venous system in right ventricle wall was similar in architecture to that in left ventricle, postcapillary venule joined its corresponding venule in a "turnip root" like pattern. No A-V anastomosis could be seen, yet thebesian vessels and myocardial sinusoids directly opened into ventrical chamber could be found.