Pretreatment with Sini decoction induces delayed preconditioning in rat heart and role of p38 MAP kinase

AIM: The present study was designed to determine whether Sini decoction (SND), a traditional Chinese medicine, induces delayed preconditioning-like effect in rat heart and the possible mechanism by which ischemia myocardium is protected. METHODS: Sprage－Dawleyt rats underwent three 5 min episodes of preconditioning ischemia 24 h prior to the global ischemia and reperfusion in ischemic preconditioning/second window of protection (IPC/SWOP) group or were pretreated with Sini decoction (5 mL·kg-1·d-1 for 3 days, the last treatment 24 h before global ischemia and reperfusion) in SND group. Myocardial infarct size, CK, LDH and NO were examined. p38 MAPK and PKC were determined by immunohistochemisty. RESULTS: Myocardial infarct size was significantly decreased, CK and LDH were decreased in the serum, NO2-/NO3- was increased in myocardial tissue in SND group as well as in IPC/SWOP group (there was no difference between the two groups). The expression of p38 MAPK and PKC were upregulated in myocardial tissue in SND and IPC/SWOP groups. CONCLUSION: These results suggest that Sini decoction induces delayed preconditioning-like effect in the rat heart, possibly via inducing p38 MAPK activation.     

Quercetin regulates Fas expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

AIM: To investigate the role of 1, 4, 5- trisphosphate inositol (IP3) and Fas gene expression in apoptosis of HepG2 cells induced by quercetin. METHODS: HepG2 cells were treated with quercetin at different concentrations (including 20, 40, 60, 80 μmol/ L) for 72 h and treated with 60 μmol/ L quercetin for 6 h, 12 h, 24 h, 48 h and 72 h. IP3, Fas mRNA, Fas protein and apoptosis rate were assayed by IP3 - ［3H］ Birtrak assay, RT-PCR, Western blotting and flow cytometry, respectively. RESULTS: When HepG2 cells were incubated with different concentrations of quercetin for 72 h, the IP3 content was lower than those in control. Fas mRNA expression, Fas protein expression and the apoptosis rate were higher than those in control. When HepG2 cells were incubated with quercetin for 6 h, 12 h, 24 h, 48 h, 72 h, the IP3 contents were lower than those in control incubated with 60 μmol/L quercetin for 12 h. Fas mRNA expression was higher than that in control incubated with 60 μmol/L quercetin for 12 h . Fas protein expression was higher than that in control. The apoptosis rate was significantly higher than that in control incubated with 60 μmol/L quercetin for 24 h (P<0.01). CONCLUSION: Quercetin induces apoptosis of HepG2 cells by reducing IP3 production and upregulating Fas gene expression.     

稻谷水分吸附与解吸等温线拟合模型的选择及其参数优化

评价5种最常用的数学模型对中国不同类型的稻谷(籼稻、粳稻、糯稻)吸附与解吸等温线数据的拟合效果，以确定最佳拟合模型及其参数。测定中国不同类型稻谷的吸附与解吸等温线数据，用非线性回归进行统计分析并评价数学模型的拟合效果。结果表明，美国农业工程学会(ASAE)推荐的修正Chung-Pfost模型及其参数并不能与中国稻谷的吸附与解吸等温线数据很好地拟合。Strohman-Yoerger模型最适于拟合籼稻、粳稻的吸附与解吸等温线及糯稻的吸附等温线。而修正Oswin模型最适合拟合糯稻的解吸等温线。Strohman-Yoerger模型拟合籼稻、粳稻吸附等温线的参数C₁、C₂、C₃、C₄分别为1.44871、0.20898、7.32345、0.18647；拟合解吸等温线的参数C₁、C₂、C₃、C₄分别为2.25071、0.24167、8.32543、0.19035；拟合珍糯吸附等温线的参数为1.55680，0.19179，6.19676，0.17155。修正Oswin模型拟合珍糯的解吸等温线的参数为13.63642，-0.05638，3.60042。本研究为中国的稻谷贮藏与加工提供了基础性数据。     

论西方休闲体育与竞技体育的融合发展

休闲体育与竞技体育同样兴起于西方，经过各自漫长的发展历程，这两种截然不同的体育形式趋向 于融合，竞技休闲化与休闲竞技化是当代体育发展的总特征。一方面，在过去民族主义推动下的传统意义 的竞技体育在向生活化、娱乐化的方向发展；另一方面，休闲体育在人类自我发展与完善的基调中，积极 引入竞争因素，从而向竞技化方向发展。而无孔不入的商业则促使休闲体育与竞技体育相互渗透与融合。     

Role of Slit2/Robo1 signaling in development of neural tube and somites in early chick embryos

AIM: To investigate the effects of Slit2/Robo1 signaling on the development of neural tube and somites in early chick embryos. METHODS: Plasmid DNA was injected into the lumen of the neural tube from dorsal side of HH10 chick embryo using microinjection, and then in ovo electroporation was performed at half-side of neural tube while another side served as control. Subsequent 10-hour incubation was carried on after transfection until the development of neural tube and neural crest cells migrating to somites were investigated using the methods of immunofluorescence and in situ hybridization. RESULTS: Blocking Slit2/Robo1 signaling resulted in abnormal development of neural tube, while the expression of Slug and neural crest cells migrating to somites pathway were abnormal as well.CONCLUSION: Slit2/Robo1 signaling can affect the expression of Slug and play an important role in the fusion of neural fold, the trajectory of generation and migration of neural crest cells, and the differentiation of somites in early chick embryos.     

Human mesenchymal stem cells differentiate into osteoblasts

AIM:To investigate the differentiation from human mesenchymal stem cells (hMSC) into osteoblasts. METHODS:MSC were separated from human marrow with Ficoll-Paque reagent and expanded in cuture medium. To detect the surface antigens, The labeled cells were analysed on a FACScan flow cytometer. hMSC were induced to differentiate from mesenchymal stem cells into osteoblasts with dexamethasone, vitamin C, β-GP. Cell morphology、AP activity、calcium deposition and osteopontin were detected. P10 MSC were compared to P3 MSC in the tendency of osteoblastic differentiation. RESULTS:The cultured MSC comprised a single phenotypic population and displayed a fibroblast-like morphology. hMSC showed a strong self-renewal capacity. After primary culture, approximately (5-6)×10⁵ cells were obtained. These expanded attached MSC were uniformaly positive for CD29,CD44,CD59,CD105,CD166 and didn’t express CD11a, CD14, CD33, CD34, CD45, CD38, CD80, CD86, CD117. After osteoblasts induction, the cells changed from spindle-shape to cuboidal and polygonal in cell morphology. The AP activity increased gradually and many scattered calcium nodes were observed. The expression of osteopontin was positive. CONCLUSION:hMSC can be induced to differentiate into osteoblasts.     

Human mesenchymal stem cells differentiate into neuron-like cells by increase in intracellular cyclic AMP

AIM: To investigate the differentiation from human mesenchymal stem cells(hMSC) into neuron-like cells by the increase in intracellular cyclic AMP. METHODS: hMSC were separated from human marrow with Ficoll-Paque reagent and expanded in culture medium. hMSC were induced to differentiate into neurons with Forskolin and 3-isobutyl-1-methyl-xanthine (IBMX). Neuron-specific enolase(NSE), neurofilament(NF), glial fibrillary acaidic protein(GFAP) were detected by immunohistochemistry. RESULTS: hMSC were expanded as undifferentiated cells in culture for more than10passages. Forskolin/IBMX can induce hMSC to exhibit a neuronal phenotype, expressing NSE and NF-M in 5 hours. But the neuron-like cells didn't express the glial astrocyte marker GFAP. CONCLUSION: hMSC can be induced to differentiate into neurons by increase in the intracellular cAMP.