A 2 149 bp full length phytoene desaturase (PDS) cDNA was first cloned from saffron (Crocus sativus L.) stigma using RT-PCR technique and a rapid amplification of cDNA end (RACE) strategy. The cDNA has an open reading...A 2 149 bp full length phytoene desaturase (PDS) cDNA was first cloned from saffron (Crocus sativus L.) stigma using RT-PCR technique and a rapid amplification of cDNA end (RACE) strategy. The cDNA has an open reading frame of 1 697 bp, which encodes a polypeptide of 565 amino acids. The coding region of the cDNA was inserted into a prokaryotic expression vector pET-21a(+) and over-expressed inE. coli BL21 (DE3). The fusion proteins were found largely in an insoluble inclusion bodies. The purified fusion protein was used to immunize rabbits to obtain polyclonal antiserum with titer of 1×105. Western blot analysis by using this particular antiserum showed that the higher expression level of PDS in mature stigma than in leaves and stamen, and the higher expression level of PDS in mature stigma than in young stigma. Key words saffron - carotenoids - phytoene desaturase - gene expression - antiserum - Western blot CLC number Q 781 - Q 786 Foundation item: Supported by the Doctoral Foundation of the Ministry of Education, P. R. China and the Young Science Foundation of Sichuan University (Grant 0020405505012)Biography: Bai Jie (1968-), female, Ph. D candidate, research direction: plant developmental biology and reproductive engineering.展开更多
Hemorrhage or hypotension induces extensive Foslike immunoreactivity in the magnocellular neurosecretory cells in the supraoptic nucleus of the hypothalamus in rat, especially in the vasopressin neurons. The present s...Hemorrhage or hypotension induces extensive Foslike immunoreactivity in the magnocellular neurosecretory cells in the supraoptic nucleus of the hypothalamus in rat, especially in the vasopressin neurons. The present study was to explore the neurotransmitter mediating this effect. Microinfusion of the alpha-adrenergic blocker into the supraoptic nucleus reduced the hypotension-induced Fos, whereas beta-antagonist did not affect it significantly. Alpha1- and alpha2-antagonist, prazosin and yohimbine,both reduced the Fos-positive cell counts. However, the effective dosage of yohimbine was much larger. Alpha1-agonist, methoxamine, induced abundant Fos-like immnnoreactivity in the vasopressin cells in this nucleus,while beta-and alpha2-agonist did not elicit such effect.Administration of the noradrenergic re-uptake inhibitor,desipramine, to this nucleus to locally accumulate the spontaneously released noradrenaline from the nerve terminals also induced Fos expression, mostly in the vasopressin cells.展开更多
AIM: To investigate whether the farnesoid X receptor (FXR) regulates expression of liver cystathionase (CSE), a gene involved in hydrogen sulfi de (H2S) generation. METHODS: The regulation of CSE expression in respons...AIM: To investigate whether the farnesoid X receptor (FXR) regulates expression of liver cystathionase (CSE), a gene involved in hydrogen sulfi de (H2S) generation. METHODS: The regulation of CSE expression in response to FXR ligands was evaluated in HepG2 cells and in wild-type and FXR null mice treated with 6-ethyl chenodeoxycholic acid (6E-CDCA), a synthetic FXR ligand. The analysis demonstrated an FXR responsive element in the 5'-flanking region of the human CSE gene. The function of this site was investigated by luciferase reporter assays, chromatin immunoprecipitation and electrophoretic mobility shift assays. Livers obtained from rats treated with carbon tetrachloride alone, or in combination with 6-ethyl chenodeoxycholic acid, were studied for hydrogen sulphide generation and portal pressure measurement. RESULTS: Liver expression of CSE is regulated by bile acids by means of an FXR-mediated mechanism. Western blotting, qualitative and quantitative polymerase chain reaction, as well as immunohistochemical analysis, showed that expression of CSE in HepG2 cells and in mice is induced by treatment with an FXR ligand. Administration of 6E-CDCA to carbon tetrachloride treated rats protected against the down-regulation of CSE expression, increased H2S generation, reduced portal pressure and attenuated the endothelial dysfunction of isolated and perfused cirrhotic rat livers. CONCLUSION: These results demonstrate that CSE is an FXR-regulated gene and provide a new molecular explanation for the pathophysiology of portal hypertension.展开更多
Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T c...Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T cell subsets in cord blood (CB) and bone marrow (BM) as well as peripheral blood (PB) was measured by immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti alkaline phosphatase (APAAP complexes) One way mixed lymphocyte cultures (MLC) were performed to compare the proliferative response of CB with that of PB The proliferative capability of cord blood T cells and T lymphocyte transformation capacity were evaluated in the presence of anti CD 8 or anti CD 5 immunotoxin by one way MLC and colorimetric MTT (tetrazolium) assay, respectively The effect of IT on the growth of hematopoietic progenitor cell of colony forming unit granulocyte and macrophage (CFU GM), burst forming unit erythroid(BFU E), multipotential hemotapoietic progenitors (CFU Mix) from CB were estimated by colony forming assays Results A certain proportion of CD 5 and CD 8 T cells existed in CB The alloproliferative capacity of CB was similar to that of PB CD 5: Ricin at a dosage of 1×10 10 -1×10 8 mmol/L and CD 8: Ricin concentration in the range of 1×10 9 -1×10 8 mmol/L effectively decreased both the proliferative capability of T cells in MLC during CB and T cell transformation Over the dosage of 1×10 10 -1×10 9 mmol/L, both kinds of IT didn't obviously affect the growth of hematopoietic progenitor cells Conclusion CD 5: Ricin and CD 8: Ricin may effectively deplete T cells and may not significantly inhibit the function of hemaptopoietic cells at a specific dosage展开更多
文摘A 2 149 bp full length phytoene desaturase (PDS) cDNA was first cloned from saffron (Crocus sativus L.) stigma using RT-PCR technique and a rapid amplification of cDNA end (RACE) strategy. The cDNA has an open reading frame of 1 697 bp, which encodes a polypeptide of 565 amino acids. The coding region of the cDNA was inserted into a prokaryotic expression vector pET-21a(+) and over-expressed inE. coli BL21 (DE3). The fusion proteins were found largely in an insoluble inclusion bodies. The purified fusion protein was used to immunize rabbits to obtain polyclonal antiserum with titer of 1×105. Western blot analysis by using this particular antiserum showed that the higher expression level of PDS in mature stigma than in leaves and stamen, and the higher expression level of PDS in mature stigma than in young stigma. Key words saffron - carotenoids - phytoene desaturase - gene expression - antiserum - Western blot CLC number Q 781 - Q 786 Foundation item: Supported by the Doctoral Foundation of the Ministry of Education, P. R. China and the Young Science Foundation of Sichuan University (Grant 0020405505012)Biography: Bai Jie (1968-), female, Ph. D candidate, research direction: plant developmental biology and reproductive engineering.
文摘Hemorrhage or hypotension induces extensive Foslike immunoreactivity in the magnocellular neurosecretory cells in the supraoptic nucleus of the hypothalamus in rat, especially in the vasopressin neurons. The present study was to explore the neurotransmitter mediating this effect. Microinfusion of the alpha-adrenergic blocker into the supraoptic nucleus reduced the hypotension-induced Fos, whereas beta-antagonist did not affect it significantly. Alpha1- and alpha2-antagonist, prazosin and yohimbine,both reduced the Fos-positive cell counts. However, the effective dosage of yohimbine was much larger. Alpha1-agonist, methoxamine, induced abundant Fos-like immnnoreactivity in the vasopressin cells in this nucleus,while beta-and alpha2-agonist did not elicit such effect.Administration of the noradrenergic re-uptake inhibitor,desipramine, to this nucleus to locally accumulate the spontaneously released noradrenaline from the nerve terminals also induced Fos expression, mostly in the vasopressin cells.
文摘AIM: To investigate whether the farnesoid X receptor (FXR) regulates expression of liver cystathionase (CSE), a gene involved in hydrogen sulfi de (H2S) generation. METHODS: The regulation of CSE expression in response to FXR ligands was evaluated in HepG2 cells and in wild-type and FXR null mice treated with 6-ethyl chenodeoxycholic acid (6E-CDCA), a synthetic FXR ligand. The analysis demonstrated an FXR responsive element in the 5'-flanking region of the human CSE gene. The function of this site was investigated by luciferase reporter assays, chromatin immunoprecipitation and electrophoretic mobility shift assays. Livers obtained from rats treated with carbon tetrachloride alone, or in combination with 6-ethyl chenodeoxycholic acid, were studied for hydrogen sulphide generation and portal pressure measurement. RESULTS: Liver expression of CSE is regulated by bile acids by means of an FXR-mediated mechanism. Western blotting, qualitative and quantitative polymerase chain reaction, as well as immunohistochemical analysis, showed that expression of CSE in HepG2 cells and in mice is induced by treatment with an FXR ligand. Administration of 6E-CDCA to carbon tetrachloride treated rats protected against the down-regulation of CSE expression, increased H2S generation, reduced portal pressure and attenuated the endothelial dysfunction of isolated and perfused cirrhotic rat livers. CONCLUSION: These results demonstrate that CSE is an FXR-regulated gene and provide a new molecular explanation for the pathophysiology of portal hypertension.
文摘Objective To study the selective toxicity of immunotoxin (IT) on T cells in cord blood and simultaneously determine its effect on hematopoietic progenitor cells Methods The percentage of CD 5 and CD 8 T cell subsets in cord blood (CB) and bone marrow (BM) as well as peripheral blood (PB) was measured by immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti alkaline phosphatase (APAAP complexes) One way mixed lymphocyte cultures (MLC) were performed to compare the proliferative response of CB with that of PB The proliferative capability of cord blood T cells and T lymphocyte transformation capacity were evaluated in the presence of anti CD 8 or anti CD 5 immunotoxin by one way MLC and colorimetric MTT (tetrazolium) assay, respectively The effect of IT on the growth of hematopoietic progenitor cell of colony forming unit granulocyte and macrophage (CFU GM), burst forming unit erythroid(BFU E), multipotential hemotapoietic progenitors (CFU Mix) from CB were estimated by colony forming assays Results A certain proportion of CD 5 and CD 8 T cells existed in CB The alloproliferative capacity of CB was similar to that of PB CD 5: Ricin at a dosage of 1×10 10 -1×10 8 mmol/L and CD 8: Ricin concentration in the range of 1×10 9 -1×10 8 mmol/L effectively decreased both the proliferative capability of T cells in MLC during CB and T cell transformation Over the dosage of 1×10 10 -1×10 9 mmol/L, both kinds of IT didn't obviously affect the growth of hematopoietic progenitor cells Conclusion CD 5: Ricin and CD 8: Ricin may effectively deplete T cells and may not significantly inhibit the function of hemaptopoietic cells at a specific dosage
