The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivisio...The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background.展开更多
[ Objective] The aim was to observe the ultrastructure of different callus structures in Heiya No. 14 by transmission electron microscopy. [Methods] Sample preparation and observation were both carried out by conventi...[ Objective] The aim was to observe the ultrastructure of different callus structures in Heiya No. 14 by transmission electron microscopy. [Methods] Sample preparation and observation were both carried out by conventional transmission electron microscopy. [ Results] It was showed by transmission electron microscopy that the initial callus cells had a large central vacuole, which squeezed its cytoplasm to be a thin layer around the brim of cell, Meanwhile the nuclear was also squeezed to distribute in the corner of cell, but its nucleolus could be still observed; Compared embryogenic callus with initial callus, its cell wall became thick, and many starch grains and chloroplasts including starch grains could be observed in the cytoplasm area of cell membrane; In non-embryoenic callus, no organelles except for the vacuole could be observed; In browning callus, there was almost no organelles in cells. [ Conclusion] There are significant differences in different types of flax callus at the cell ultrastructure level, which can be as an index for reflecting the differentiation ability of callus cell.展开更多
Objective To construct signal transduction and activators of transcription 3 (STAT3) short hairpin RNA (shRNA) expression vector and to investigate its inhibitory effects on STAT3 expression, cell proliferation and ap...Objective To construct signal transduction and activators of transcription 3 (STAT3) short hairpin RNA (shRNA) expression vector and to investigate its inhibitory effects on STAT3 expression, cell proliferation and apoptosis of human pancreatic cancer. Methods Three pairs of hairpin-like oligonucleotide sequences specific for human STAT3 gene were designed and synthesized. The annealed oligonucleotide fragments were subcloned into pRNAT-U6.1/Neo plasmid. The STAT3 shRNA expressing vectors were confirmed by PCR and DNA sequencing. STAT3 mRNA and protein expression were examined by using reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. MTT assay and flow cytometry were performed to detect the state of cell proliferation and cell apoptosis, respectively. Results PCR and DNA sequencing showed that the oligonucleotide fragments were correctly inserted into pRNAT-U6.1/Neo plasmid. STAT3 expression and cell proliferation in the transfected cells was inhibited significantly by three STAT3 shRNA expressing vectors (P<0.05). ConclusionSTAT3 shRNA expression vector can effectively inhibit the expression of STAT3. Silencing of STAT3 with RNAi can significantly inhibit the proliferation and promotes the apoptosis of pancreatic cancer cells and may provide a novel therapeutic target for treating pancreatic cancer.展开更多
Much has been written and researched about transformational change and the exogenous events that result in radical institutional transformation (Di Maggio & Powell, 1983; Hannan& Freeman, 1989; Fligstein, 1996; Zor...Much has been written and researched about transformational change and the exogenous events that result in radical institutional transformation (Di Maggio & Powell, 1983; Hannan& Freeman, 1989; Fligstein, 1996; Zorn, Dobbin, & Kwok, 2006). Accounts are provided of external agents disturbing the existing stasis of the institution and transforming the institution into something else that reflect a new paradigm or set of interests. Often, what is neglected in these accounts is what fractures exist in the original institution that would make them vulnerable and allow penetration by exogenous influences. Mahoney and Thelen (20 l 0) went beyond a general model of change that described the collapse of one set of institutional norms to be replaced by another. The model of change they propose takes into account both exogenous as well as endogenous factors as being the source of institutional change. They went on to state a view that transformation change as being a result of abrupt, wholesale breakdown needs to be rethought to include incremental, endogenous shifts in thinking that can often result in fundamental transformations.展开更多
AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by ...AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a doseand timedependent manner. It did notaffect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a doseand time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.展开更多
Fertilized rabbit eggs injected with SMTPGH gene were cultured in vitro and retention of theinjected gene was studied using PCR technique and nonradioactive labelling methed. In a mediumof TC199 + 10% FCS, three quart...Fertilized rabbit eggs injected with SMTPGH gene were cultured in vitro and retention of theinjected gene was studied using PCR technique and nonradioactive labelling methed. In a mediumof TC199 + 10% FCS, three quarters of the fertilized eggs developed to the blastocyst stage. Noapparent change of the injected gene was found before the 8-cell stage, after which it was eitherintegrated into the chromosome of the host or lost gradually. But finally, the retention rate of theinjected gene should be equal to its integration rate.展开更多
An efficient in vitro protocol for mass production of shoot of Dahlia was developed by using node explant, various carbon sources such as sucrose, glucose, fructose and galactose. Agar concentrations and various growt...An efficient in vitro protocol for mass production of shoot of Dahlia was developed by using node explant, various carbon sources such as sucrose, glucose, fructose and galactose. Agar concentrations and various growth regulators on in vitro shoot multiplication of Dahlia were studied in the present investigation. The nodal explant from the gardens grown plant were used as testing plant material to develop an efficient protocol for mass propagation of exotic Dahlia to enhance their production for growers and the local markets. This study determined the effect of different carbon sucrose concentrations and gelling agent on in vitro propagation of Dahlia, different carbon sources (sucrose, glucose, fructose and galactose) were investigated, each sugar was added individually to the MS culture medium at the concentrations of 15, 30 and 45 g·L^-1, respectively. Culture medium of each treatment was supplemented with 1,5 mg·L^-1 BA + 1.5 mg·L^-1Kin + 7,0 g·L^-1 agar. The highest number of shoots (7.00), number of leaves (11.50), number of node (6.75) and shoot length (8.24 cm) was obtained on MS medium supplemented with 30 g·L^-1 glucose. The least number of shoots (3.38), number of leaves (5.00), number of node (3.13) and the least shoot length (2.96 cm) was obtained on 45 g·L^-1 galactose and the least shoot length (2.29 cm) was observed on MS medium with free carbon sources. While the medium with 30 g·L^-1 glucose and 8 g·L^-1 agar gave the highest number of shoots (7.13), number of leaves (10.75), number of node (7.13) and shoot length (8.18 cm). However, the least number of shoots (1.50), number of leaves (1.88), number of node (1.63) and the least shoot length (1.26 cm) was obtained with 30 g·L^-1 galactose and 12 g·L^-1 agar. Rooting was readily achieved upon transferring the microshoots onto MS medium supplemented with 0.1 mg·L^-1 IBA, IAA and NAA and 30 g·L^-1 (w/v) different types of carbon sources. The percentage of rooting was less (71.88%) on MS medium containing IAA as compared with IBA or NAA. While the medium having 30 g·L^-1 glucose with 0.1 IBA or NAA mg·L^-1, give the highest percentage of root (100%), and the highest number of root (3.88) and root length (3.56 cm) was obtained on MS medium containing 30 g·L^-1 glucose with 0.1 mg·L^-1 IBA. More than 98% of rooted plantlets were established in the greenhouse.展开更多
文摘The behavior of wheat-rye translocation chromosome and alien chromosome including Thinopyrum and Haynaldia chromosome at meiosis was investigated in two hybrids by fluorescence in situ hybridization (FISH). Misdivision of translocation chromosome at anaphase I and rye chromatin micronucleus at tetrad stage were observed, A plant with one normal 1BL/1RS translocation chromosome and one 1BL/1RS translocation chromosome deleted about 1/3 of rye chromosome arm in length was identified. One plant with wheat-Thinopyrum non-Robertson translocation chromosome was also detected in the F-2 population of Yi4212 x Yi4095. That could be the results of unequal misdivision of wheat-rye 1BL/1RS translocation chromosome and Thinopyrum chromosome during meiosis. No interaction between translocation chromosome and alien chromosome at meiosis was supported by the data of the distribution frequencies of translocation chromosome and Thinopyrum or Haynaldia chromosome in the progeny of two hybrids. The results may be useful to cultivate new germplasms with different length of rye 1R short arm and wheat-alien non-Robertson translocation tines under wheat background.
基金Supported by Harbin Postdoctoral Foundation(LRB08-491)~~
文摘[ Objective] The aim was to observe the ultrastructure of different callus structures in Heiya No. 14 by transmission electron microscopy. [Methods] Sample preparation and observation were both carried out by conventional transmission electron microscopy. [ Results] It was showed by transmission electron microscopy that the initial callus cells had a large central vacuole, which squeezed its cytoplasm to be a thin layer around the brim of cell, Meanwhile the nuclear was also squeezed to distribute in the corner of cell, but its nucleolus could be still observed; Compared embryogenic callus with initial callus, its cell wall became thick, and many starch grains and chloroplasts including starch grains could be observed in the cytoplasm area of cell membrane; In non-embryoenic callus, no organelles except for the vacuole could be observed; In browning callus, there was almost no organelles in cells. [ Conclusion] There are significant differences in different types of flax callus at the cell ultrastructure level, which can be as an index for reflecting the differentiation ability of callus cell.
文摘Objective To construct signal transduction and activators of transcription 3 (STAT3) short hairpin RNA (shRNA) expression vector and to investigate its inhibitory effects on STAT3 expression, cell proliferation and apoptosis of human pancreatic cancer. Methods Three pairs of hairpin-like oligonucleotide sequences specific for human STAT3 gene were designed and synthesized. The annealed oligonucleotide fragments were subcloned into pRNAT-U6.1/Neo plasmid. The STAT3 shRNA expressing vectors were confirmed by PCR and DNA sequencing. STAT3 mRNA and protein expression were examined by using reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. MTT assay and flow cytometry were performed to detect the state of cell proliferation and cell apoptosis, respectively. Results PCR and DNA sequencing showed that the oligonucleotide fragments were correctly inserted into pRNAT-U6.1/Neo plasmid. STAT3 expression and cell proliferation in the transfected cells was inhibited significantly by three STAT3 shRNA expressing vectors (P<0.05). ConclusionSTAT3 shRNA expression vector can effectively inhibit the expression of STAT3. Silencing of STAT3 with RNAi can significantly inhibit the proliferation and promotes the apoptosis of pancreatic cancer cells and may provide a novel therapeutic target for treating pancreatic cancer.
文摘Much has been written and researched about transformational change and the exogenous events that result in radical institutional transformation (Di Maggio & Powell, 1983; Hannan& Freeman, 1989; Fligstein, 1996; Zorn, Dobbin, & Kwok, 2006). Accounts are provided of external agents disturbing the existing stasis of the institution and transforming the institution into something else that reflect a new paradigm or set of interests. Often, what is neglected in these accounts is what fractures exist in the original institution that would make them vulnerable and allow penetration by exogenous influences. Mahoney and Thelen (20 l 0) went beyond a general model of change that described the collapse of one set of institutional norms to be replaced by another. The model of change they propose takes into account both exogenous as well as endogenous factors as being the source of institutional change. They went on to state a view that transformation change as being a result of abrupt, wholesale breakdown needs to be rethought to include incremental, endogenous shifts in thinking that can often result in fundamental transformations.
基金Supported by The National Natural Science Foundation of China (No. 30872481)the Scientific and Technological Planning Foundation of Shaanxi Province (No. 2006K09-G7-1)
文摘AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a doseand timedependent manner. It did notaffect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a doseand time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.
基金This work was supported by National High Technoloqy Grants 86310105.
文摘Fertilized rabbit eggs injected with SMTPGH gene were cultured in vitro and retention of theinjected gene was studied using PCR technique and nonradioactive labelling methed. In a mediumof TC199 + 10% FCS, three quarters of the fertilized eggs developed to the blastocyst stage. Noapparent change of the injected gene was found before the 8-cell stage, after which it was eitherintegrated into the chromosome of the host or lost gradually. But finally, the retention rate of theinjected gene should be equal to its integration rate.
文摘An efficient in vitro protocol for mass production of shoot of Dahlia was developed by using node explant, various carbon sources such as sucrose, glucose, fructose and galactose. Agar concentrations and various growth regulators on in vitro shoot multiplication of Dahlia were studied in the present investigation. The nodal explant from the gardens grown plant were used as testing plant material to develop an efficient protocol for mass propagation of exotic Dahlia to enhance their production for growers and the local markets. This study determined the effect of different carbon sucrose concentrations and gelling agent on in vitro propagation of Dahlia, different carbon sources (sucrose, glucose, fructose and galactose) were investigated, each sugar was added individually to the MS culture medium at the concentrations of 15, 30 and 45 g·L^-1, respectively. Culture medium of each treatment was supplemented with 1,5 mg·L^-1 BA + 1.5 mg·L^-1Kin + 7,0 g·L^-1 agar. The highest number of shoots (7.00), number of leaves (11.50), number of node (6.75) and shoot length (8.24 cm) was obtained on MS medium supplemented with 30 g·L^-1 glucose. The least number of shoots (3.38), number of leaves (5.00), number of node (3.13) and the least shoot length (2.96 cm) was obtained on 45 g·L^-1 galactose and the least shoot length (2.29 cm) was observed on MS medium with free carbon sources. While the medium with 30 g·L^-1 glucose and 8 g·L^-1 agar gave the highest number of shoots (7.13), number of leaves (10.75), number of node (7.13) and shoot length (8.18 cm). However, the least number of shoots (1.50), number of leaves (1.88), number of node (1.63) and the least shoot length (1.26 cm) was obtained with 30 g·L^-1 galactose and 12 g·L^-1 agar. Rooting was readily achieved upon transferring the microshoots onto MS medium supplemented with 0.1 mg·L^-1 IBA, IAA and NAA and 30 g·L^-1 (w/v) different types of carbon sources. The percentage of rooting was less (71.88%) on MS medium containing IAA as compared with IBA or NAA. While the medium having 30 g·L^-1 glucose with 0.1 IBA or NAA mg·L^-1, give the highest percentage of root (100%), and the highest number of root (3.88) and root length (3.56 cm) was obtained on MS medium containing 30 g·L^-1 glucose with 0.1 mg·L^-1 IBA. More than 98% of rooted plantlets were established in the greenhouse.