Objective: To investigate the therapeutic effect of a novel suicide gene system, yeast cytosine deaminase (YCD)/5-Fluorocytosine(5-FC), on P388/DBA murine leukemia model. Methods: P388-YCD-eGFP clone was selected afte...Objective: To investigate the therapeutic effect of a novel suicide gene system, yeast cytosine deaminase (YCD)/5-Fluorocytosine(5-FC), on P388/DBA murine leukemia model. Methods: P388-YCD-eGFP clone was selected after retrovirus transduction by limited dilution. P388-eGFP and wild type (wt) P388 cells were used as controls. (1) Tumorigenesis study: DBA mice were inoculated intravenously with P388-YCD-eGFP, P388-eGFP or wt P388 cells at a dosage of 5×10~6 per mouse (n=5). (2) Therapeutic effect study of 5-FC: After inoculation with P388-YCD-eGFP, P388-eGFP or wt P388 cells (n=5), 5-FC was administered at a dosage of 5 μmol/d in each mouse for 2 weeks. 20 μmol/d 5-FC were administered on the 8~ th day in case 5 μmol/d did not work. The percentage of eGFP^+ cells was detected by flow cytometry, frozen section or HE section. Results: Mice in YCD, eGFP and wt P388 group developed leukemia and survived (8.0±1.0) d, (7.6±0.89) d and (7.8±1.64) d (P>0.05), respectively. After being treated with 5-FC for 2 weeks, mice in YCD and eGFP^+ groups survived (13.2±1.79) d and (8.4±0.58) d (P<0.05). When 20 μmol/d 5-FC was administered, the percentage of eGFP^+ cells dropped from 21.9%±16.09% to 5.4%±5.6%, as well detected by FACS within 24h after treatment. Conclusion: 5-FC can eliminate YCD gene modified cells in vivo when cells are inoculated intravenously. YCD is an efficient suicide gene system in vivo.展开更多
Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on l...Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species.展开更多
脱氧血腐镰刀菌烯醇(deoxynivalenol,DON)在小麦赤霉病发病过程中起重要作用,是一种毒性因子.禾谷镰刀菌的侵染能力依赖于其产生DON的能力,抗病品种能显著降低病穗组织中DON的含量.本研究利用Affymetrix小麦基因组芯片,对抗赤霉病小麦...脱氧血腐镰刀菌烯醇(deoxynivalenol,DON)在小麦赤霉病发病过程中起重要作用,是一种毒性因子.禾谷镰刀菌的侵染能力依赖于其产生DON的能力,抗病品种能显著降低病穗组织中DON的含量.本研究利用Affymetrix小麦基因组芯片,对抗赤霉病小麦品种望水白经DON诱导后的穗组织基因表达特点进行了分析,结果发现,一个编码PDR型转运蛋白的EST受DON诱导后上调表达45倍.根据该EST设计引物筛选小麦基因组TAC文库,得到一个包含该基因的TAC单克隆.利用染色体walking对该单克隆测序,用Softberry软件进行基因预测,根据预测基因的5′和3′非翻译区设计引物,从DON诱导的小麦望水白穗组织cDNA中克隆出该转运蛋白基因.该基因组全长7377bp,包含19个外显子,CDS长度为4308bp,编码长1435aa且分子量161kD的蛋白.蛋白序列比对表明,该基因属于PDR蛋白家族,命名为TaPDR1(Triticum asetivum Pleiotropic Drug Resistance).利用一套中国春缺体-四体系将TaPDR1基因定位在小麦5A染色体上.半定量RT-PCR表明,TaPDR1在望水白穗中受DON和禾谷镰刀菌诱导表达,表明其参与了植物抗病防御反应.该基因在望水白感病突变体中低水平表达,进一步证明TaPDR1与赤霉病抗性有关.TaPDR1的表达不受与生物胁迫相关的激素(JA和SA)和非生物胁迫因子(热、冷、伤害和NaCl)的诱导,但受到Al3+和游离Ca2+的诱导表达,推测[Ca2+]i介导了TaPDR1的表达信号.展开更多
Objective: To explore the effect of homeobox B2 (HOXB2) antisense oligodeoxynucleotides (asodn) on the proliferation and expression of primary human umbilical vein endothelial cells (HUVECs). Methods: Various concentr...Objective: To explore the effect of homeobox B2 (HOXB2) antisense oligodeoxynucleotides (asodn) on the proliferation and expression of primary human umbilical vein endothelial cells (HUVECs). Methods: Various concentrations of HOXB2 asodn modified by thiophosphate transfected the induction of liposome into HUVECs. MTT and RT-PCR methods were employed to determine the effect of different concentrations of asodn on the endothelial proliferation and the expression level of HOXB2 mRNA. Results: After the transfection of HOXB2 asodn, the endothelial proliferation was inhibited in a dose-dependent fashion. Simultaneously, the expression of HOXB2 mRNA decreased significantly. Conclusions: HOXB2 plays an important role in the proliferation of endothelia.展开更多
基金Supported in part by grants from"Outstanding physicianProgram" of public Health Department of ShanghaiMunicipal Government,China(98BR0 2 9),National NaturalScience Foundation of China(30 170 379
文摘Objective: To investigate the therapeutic effect of a novel suicide gene system, yeast cytosine deaminase (YCD)/5-Fluorocytosine(5-FC), on P388/DBA murine leukemia model. Methods: P388-YCD-eGFP clone was selected after retrovirus transduction by limited dilution. P388-eGFP and wild type (wt) P388 cells were used as controls. (1) Tumorigenesis study: DBA mice were inoculated intravenously with P388-YCD-eGFP, P388-eGFP or wt P388 cells at a dosage of 5×10~6 per mouse (n=5). (2) Therapeutic effect study of 5-FC: After inoculation with P388-YCD-eGFP, P388-eGFP or wt P388 cells (n=5), 5-FC was administered at a dosage of 5 μmol/d in each mouse for 2 weeks. 20 μmol/d 5-FC were administered on the 8~ th day in case 5 μmol/d did not work. The percentage of eGFP^+ cells was detected by flow cytometry, frozen section or HE section. Results: Mice in YCD, eGFP and wt P388 group developed leukemia and survived (8.0±1.0) d, (7.6±0.89) d and (7.8±1.64) d (P>0.05), respectively. After being treated with 5-FC for 2 weeks, mice in YCD and eGFP^+ groups survived (13.2±1.79) d and (8.4±0.58) d (P<0.05). When 20 μmol/d 5-FC was administered, the percentage of eGFP^+ cells dropped from 21.9%±16.09% to 5.4%±5.6%, as well detected by FACS within 24h after treatment. Conclusion: 5-FC can eliminate YCD gene modified cells in vivo when cells are inoculated intravenously. YCD is an efficient suicide gene system in vivo.
基金Supported by the Special Research Fund for the National Non-profit Institutes (No. 2007M24)the Shanghai Postdoctoral Scientific Program (No. 07R214165)+1 种基金the National Natural Science Foundation of China (No. 40776047)the National Basic Research Program of China (973 Program) (No. 2010CB429005)
文摘Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species.
文摘脱氧血腐镰刀菌烯醇(deoxynivalenol,DON)在小麦赤霉病发病过程中起重要作用,是一种毒性因子.禾谷镰刀菌的侵染能力依赖于其产生DON的能力,抗病品种能显著降低病穗组织中DON的含量.本研究利用Affymetrix小麦基因组芯片,对抗赤霉病小麦品种望水白经DON诱导后的穗组织基因表达特点进行了分析,结果发现,一个编码PDR型转运蛋白的EST受DON诱导后上调表达45倍.根据该EST设计引物筛选小麦基因组TAC文库,得到一个包含该基因的TAC单克隆.利用染色体walking对该单克隆测序,用Softberry软件进行基因预测,根据预测基因的5′和3′非翻译区设计引物,从DON诱导的小麦望水白穗组织cDNA中克隆出该转运蛋白基因.该基因组全长7377bp,包含19个外显子,CDS长度为4308bp,编码长1435aa且分子量161kD的蛋白.蛋白序列比对表明,该基因属于PDR蛋白家族,命名为TaPDR1(Triticum asetivum Pleiotropic Drug Resistance).利用一套中国春缺体-四体系将TaPDR1基因定位在小麦5A染色体上.半定量RT-PCR表明,TaPDR1在望水白穗中受DON和禾谷镰刀菌诱导表达,表明其参与了植物抗病防御反应.该基因在望水白感病突变体中低水平表达,进一步证明TaPDR1与赤霉病抗性有关.TaPDR1的表达不受与生物胁迫相关的激素(JA和SA)和非生物胁迫因子(热、冷、伤害和NaCl)的诱导,但受到Al3+和游离Ca2+的诱导表达,推测[Ca2+]i介导了TaPDR1的表达信号.
基金theNationalKeyBasicResearchProjectofChina (No .G19990 5 42 0 5 )
文摘Objective: To explore the effect of homeobox B2 (HOXB2) antisense oligodeoxynucleotides (asodn) on the proliferation and expression of primary human umbilical vein endothelial cells (HUVECs). Methods: Various concentrations of HOXB2 asodn modified by thiophosphate transfected the induction of liposome into HUVECs. MTT and RT-PCR methods were employed to determine the effect of different concentrations of asodn on the endothelial proliferation and the expression level of HOXB2 mRNA. Results: After the transfection of HOXB2 asodn, the endothelial proliferation was inhibited in a dose-dependent fashion. Simultaneously, the expression of HOXB2 mRNA decreased significantly. Conclusions: HOXB2 plays an important role in the proliferation of endothelia.
