Effect of baicalein on pancreas insulin secretion in rats and its mechanism / 中国药理学通报

Aim To investigate the effect of baicalein on insulin secretion from rat islets and the underlying mechanism. Methods Pancreatic islets were obtained from the pancreas of male Wistar rats by collagenase P digestion and histopaque-1077 density gradient separa-tion. Single islet cells were dispersed from pancreatic islets by Dispase II digestion. Insulin secretion experi-ment was applied to observe insulin release after baica-lein stimulation. To study the potential mechanism, calcium imaging technique and patch-clamp experiment were applied to measure intracellular Ca2+ concentra-tion and voltage-dependent potassium channel currents (Kv). Results In 16. 7mmol·L-1 glucose, baica-lein accelerated insulin secretion in a dose-dependent manner. Baicalein promoted the intracellular Ca2+ con-centration. The patch-clamp experiment showed that baicalein inhibited Kv current in a dose-dependent manner. Conclusion Baicalein can increase the in-tracellular Ca2+ concentration by inhibiting Kv chan-nels and eventually promoting insulin secretion.

Optimum harvest time of Tulipa edulis based on comparison of biomass accumulation and medicinal quality evaluation / 中国中药杂志

The optimum harvest time of Tulipa edulis was explored based on biomass accumulation and medicinal quality evaluation. Samples were taken from bud stage (Feb 13th) to dormancy stage (May 14th) and the growth indexes, organs biomasses, drying rate, contents of water-soluble extract and polysaccharides were determined. The results showed that biomass distribution of T. edulis varied with growth center and the bulb gained maximum biomass allocation in the whole growth period. The total biomass accumulation and bulb biomass accumulation　increased in the whole growth period and peaked in fructescence stage. No differences were observed in bulb biomass among fructescence stage, withering stage and dormancy stage. The correlation between bulb biomass allocation and other morphological indexes varied with the harvest time. Bulb dry weight biomass had negative correlation with some morphological indexes of aerial part of T. edulis at bud stage, flower stage and fructescence and had significant positive (P<0.05) or extremely significant positive correlation（P<0.01）with other morphological indexes except for root at bearing fruits stage. The drying rate of bulb of T. edulis increased with the extension of harvest time and peaked in dormancy stage. The water-soluble extract of T. edulis bulb was the highest in pre-growing-stage. The tendency of polysaccharides contents showed a W-shape variation during the harvesting period. The polysaccharides content was the lowest in fructescence stage and was the highest in dormancy stage. Considering the yield and medicinal quality of T. edulis bulb, the optimum harvest time of T. edulis is in the withering stage or early stage of dormancy.

Growth and reproductive characteristics of different grades of Tulipa edulis bulb / 中草药

Objective: To explore the growth and reproductive characteristics of different grades of Tulipa edulis bulb. Methods: T. edulis bulbs were divided into four grades based on weight, e.g. the 1st grade, m > 2.0 g; the 2nd grade, m 1.0-2.0 g; the 3rd grade, m 0.5-1.0 g, and the 4th grade, m < 0.5 g. The growth indexes, flowering and fruiting percentage, and photosynthetic characteristics were measured at vigorous growth period. And the yield, reproduction coefficient, and net yield-increasing percentage were calculated at harvest period. Results: The growth indexes increased with the increasing weight of bulbs. In comparison with the 3rd and 4th grades bulbs, the 1st and 2nd grades bulbs showed higher photosynthetic efficiency, and net yield-increasing percentage. The bulbs, weight of which were higher than 1 g, showed high flowering and fruiting percentage. Conclusion: The 1st and 2nd grades bulbs are suitable to be reproductive materials for bulbs, while the 3rd and 4th grades bulbs are more applicable as materials for producing seeds.

Effects of different drying methods on processing performance and quality in bulbus of Tulipa edulis / 中国中药杂志

Effects of different drying methods including sun drying, steamed, boiled, constant temperature drying (at 40, 50, 60 °C) on appearance, hardness, rehydration ratio, dry rate, moisture, total ash, extractive and polysaccharides contents were studied to provide the basis of standard processing method for Tulipa edulis bulbus. The results showed that the treatments of sun drying and 40 °C drying showed higher rehydration ratios, but lower dry rate, higher hardness, worse color, longer time and obvious distortion and shrinkage in comparison with other drying methods. The treatments of 60 °C constant temperature drying resulted in shorter drying time, lower water and higher polysaccharides content. Drying time is shorter and appearance quality is better in the treatment of steaming and boiling compared with other treatments, but the content of extractive and polysaccharides decreased significantly. The treatments of 50 °C constant temperature drying led to similar appearance quality of bulb to commercial bulb, and it resulted in lowest hardness and highest dry rate as well as higher rehydration ratio, extractive and polysaccharides content, moderate moisture and total ash contents among these treatments. Based on the results obtained, 50 °C constant temperature drying is the better way for the processing of T. edulis bulbus.

Effects of low temperature on dormancy breaking and growth after planting in bulbs of Tulipa edulis / 中国中药杂志

The effect of low temperature storage on dormancy breaking, sprouting and growth after planting of Tulipa edulis was studied. The results showed that starch content and activity of amylases significantly decreased during 10 weeks of cold storage, soluble protein content raised at first then decreased, and the peak appeared at the 6th week. However, total soluble sugar content which in- creased slowly at first than rose sharply and reducing sugar content increased during the storage duration. The bulbs with cold storage treatment rooted in the 6th week, which was about 2 weeks earlier than room temperature storage, but there were less new roots in the late period of storage. After stored at a low temperature, bud lengths were longer than that with room temperature treatment. Cold storage treatment could promote earlier emergence, shorten germination time, prolong growth period and improve the yield of bulb, but rarely affect the emergence rate. It was not beneficial to flowering and fruiting. The results indicated that 6-8 weeks of cold storage was deemed to be the key period of dormancy breaking preliminary.

Proteome analysis and tissue array for profiling protein markers associated with type B thymoma subclassification / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The prognostic relevance of World Health Organization (WHO) subtypes within type B thymomas is still controversial. Understanding of the molecular characteristics of the different histologic types of thymomas will provide meaningful information for diagnosis and therapeutic management in type B thymoma.</p><p><b>METHODS</b>Proteins extracted from twelve type B thymoma tissue specimens (six type B1 and six type B2) were analyzed by two-dimensional electrophoresis (2-DE) coupled with MALDI-TOF-MS. Differentially expressed proteins were then assayed in sixty-nine type B thymoma tissues (including B1, B2 and B3) by tissue array analysis with immunohistochemistry staining. The relationship of their expression with clinicopathological parameters, such as tumor stage or WHO classification, was estimated by Spearman's Rank Correlation Test.</p><p><b>RESULTS</b>Sixteen differentially expressed proteins between type B1 and B2 thymoma tissues were identified. The differential levels of ezrin and glutathione S-transferase pi (GSTP1) were validated using immunohistochemistry staining. A statistically significant difference was observed in the positive rate of ezrin expression between type B1 thymoma and type B3 thymoma (Z = -2.963, P < 0.01). Ezrin showed a tendency to be expressed in higher classification tumors from type B1 to B3. A statistical analysis demonstrated that type B2 and B3 tumors had significantly higher positive expression of GSTP1 than the B1 group (type B2 vs. B1: Z = -2.582, P = 0.01; type B3 vs. B1: Z = -4.012, P ≤ 0.001). The results also showed a strong correlation between GSTP1 and WHO type staging of B1 to B3 tumors (Spearman's correlation coefficient: 0.633, P ≤ 0.001). Statistical analysis showed that there was close correlation between GSTP1 and ezrin expression with the clinical stage (Spearman's correlation coefficients, ezrin: 0.481, P < 0.05; GSTP1: 0.484, P < 0.01).</p><p><b>CONCLUSIONS</b>Differentially expressed proteins between type B1 and B2 thymoma tissues were analyzed by comparative proteomic analysis. The techniques of proteomic analysis and tissue array provide a potential tool for screening of key molecules in type B thymoma histological sub-classifications. The statistical analysis of ezrin and GSTP1 expression by immunohistochemistry, especially GSTP1, may be a useful approach for type B thymoma classification.</p>

Effects of α-methylnorepinephrine on cardiac function and myocardium at early stage of resuscitation in rabbits / 世界急诊医学杂志（英文）

BACKGROUND:Recent studies have shown that α2-adrenergic agonists can reduce postresuscitation myocardial injury. This study was undertaken to observe changes of hemodynamics, myocardial injury markers cTnT and cardiac morphology by establishing a cardiopulmonary resuscitation model with rabbits, and to detect whether α-methyl norepinephrine (α-MNE) can reduce the myocardial injury after CPR and improve cardiac function. METHODS:Eighteen health rabbits, weighing 2.5-3.5 kg, both male and female, were provided by the Lanzhou Institute of Veterinary Medicine. After setting up a rabbit model of cardiopulmonary resuscitation, 18 rabbits were randomly divided into three groups. The rabbits in group A as an operation-control group were subjected to anesthesia, endotracheal intubation, and surgery without induction of ventricular fibrillation. The rabbits in group B as an epinephrine group were administered with 30 g/kg epinephrineduring CPR. The rabbits in group C as a MNE group were administered with 100 g/kg a-MNE during CPR. The left ventricular end-diastolic pressure (LVEDP), left ventricular pressure rise and fall rate (±dp/dt) and serum concentrations of BNP were measured. Statistical package of SPSS 10.0 was used for data analysis and significant differences between means were evaluated by ANOVA. RESULTS:Compared to group A, the LVEDP of other two groups increased respectively (P<0.01 all), and peak±dp/dt decreased in the other two groups (P<0.01). The increase of LVEDP was lower in group C than in group B (P<0.05), whereas peak±dp/dt was higher in group C than in group B (P<0.05) at the same stage. Compared to group A, the cTnT of the remaining two groups increased, respectively (P<0.01), and peaked at 30 minutes. cTnT was less elevated in group C than in group B (P<0.05) during the same period. In groups B and C, myocardial injury was seen under a light microscope, but the injury in group C was lighter than that in group B. CONCLUSION:Methylnorepinephrine can lessen myocardial dysfunction after CPR.

D2 receptor expression on immortalized human neural progenitor cell line hNPC-TERT in vitro and in vivo / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe D(2) receptor expression on human neural progenitor cell line hNPC-TERT before and after transplantation into rabbit central nervous system.</p><p><b>METHODS</b>D(2) receptor expression on cultured hNPC-TERT cells was verified and quantitatively analyzed with immunofluorescence assay and receptor radio ligand binding assay, respectively. 3 x 10(6) hNPC-TERT cells were implanted in the spinal cord of New Zealand rabbit with HeLa cells as the control. Two days after implantation, positron-emission tomography (PET) scan with (11)C-raclopride as the radiotracer was performed in the living animals or for the isolated spinal cords, and cryosections of the spinal cord containing the implanted cells were prepared for immunofluorescence assay.</p><p><b>RESULTS</b>Cultured hNPC-TERT cells showed high expression of D(2) receptor (Bmax=8 x 10(4)). PET scans of the rabbits identified visible radioactive accumulations at the site where hNPC-TERT cells were implanted but not at the site of HeLa cell implantation. Region of interest analysis showed a significant difference between the two cells in the maximal standard uptake value at the cell implantation sites. The results were further confirmed with ex vivo PET imaging of the spinal cord and tissue immunofluorescence assay.</p><p><b>CONCLUSION</b>Human neural progenitor cells hNPC-TERT highly express dopamine D(2) receptors and retain this capacity after implantation into the spinal cord, suggesting their potential for treatment of such nerve system disease as Parkinson syndrome.</p>

Construction of the eukaryotic expression vector containing rat transforming growth factor beta type II receptor and interferon gamma fusion genes / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To express a bioactive fusion protein comprising rat soluble transforming growth factor beta type II receptor and interferon gamma(rsTGFbetaR II-IFN gamma) in mammalian cells.</p><p><b>METHODS</b>mRNA was extracted from rat liver and the sTGFbetaR II-IFN gamma genes amplified by RT-PCR, then the two gene segments were cloned into the same pSecTag2A expression vector, and pSecTag2A/rsTGFbetaR II-IFN gamma recombinant plasmid was obtained, which was later transfected into CHO cells using liposomes. The expression of pSecTag2A/rsTGFbetaR II-IFN gamma in the supernatant was detected by ELISA and Western blotting. The bioactivities of the fusion protein were tested by sTGF betaR II-IFN gamma and IFN gamma bioassays.</p><p><b>RESULTS</b>pSecTag2A/rsTGFbetaR II-IFN gamma transfectants expressed rsTGF betaR II-IFN gamma fusion protein. The purified fusion protein exhibited anti-viral activity and antagonized the proliferation-inhibitive effect of TGFbeta1 on CCL-64 cells. It inhibits the HSC activation in vitro.</p><p><b>CONCLUSION</b>The pSecTag2A/rsTGFbetaR II-IFN gamma recombinant plasmid constructed in this study can express bioactive rsTGFbetaR II-IFN gamma fusion protein.</p>

Two-dimensional electrophoresis and mass spectrometry analysis on effects of trichloroethylene on protein of L-02 liver cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effects of trichloroethylene (TCE) on the protein in L-02 cells in vitro.</p><p><b>METHODS</b>Thiazolyl blue and Trypan blue tests were used to investigate the cytotoxicity of TCE to L-02 liver cell. The 2-D electrophoresis was used to analyse the expression of proteins in L-02 liver cells. The differentially expressed protein spots were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF-MS).</p><p><b>RESULTS</b>When the concentration of TCE exceeded 30 micromol/L, there was distinct cytotoxicity to L-02 cell (P < 0.05). Selected 40 micromol/L to treat L-02 liver cells and analyze the differential proteome expression, the results showed that the expression level of 37 protein spots was up-regulated and 15 protein spots was down-regulated. And 15 proteins were identified by MALDI-TOF-TOF-MS.</p><p><b>CONCLUSION</b>TCE can change the proteome expression of L-02 liver cell. It should provide the fundamental information to identify proteins related to TCE in further study.</p>

Construction and expression of the eukaryotic expression vector containing human soluble transforming growth factor beta receptor II / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct a eukaryotic expression vector encoding the gene of extracellular region of type II transforming growth factor beta receptor (sTGFbetaR II), to express the protein in CHO cell line and to determine its biological activity.</p><p><b>METHODS</b>The extracellular region (amino acids 1-159) of the human TGFbetaR II cDNA was amplified by PCR from a TGFbetaR II chimeric plasmid,and the eukaryotic expression plasmid pCDNA3.1/myc-his(-)B-sTGFbetaR II(pCDNA-sTGFbetaR II) was constructed by inserting the sTGFbetaR II cDNA into the EcoR I/Hind III-digested pCDNA. The DNA sequence was confirmed by double digestion and the pCDNA-sTGFbetaR II plasmid was transfected into the CHO cell line. The sTGFbetaR II protein was confirmed by Western blotting analysis and its biological function was determined.</p><p><b>RESULTS</b>The specific protein was observed in western blotting, and the protein abrogated the growth-inhibitory effects of TGF-beta1 on mink lung epithelial cells (Mv1Lu).</p><p><b>CONCLUSION</b>The eukaryotic expression plasmid pCDNA-sTGFbetaR II has been successfully constructed and the sTGFsTGFbetaR II protein with biological activity obtained.</p>