Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mech...Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4′,6′-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^+ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^+- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP+ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.展开更多
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all...As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.展开更多
We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-α-308G/A on the onset and development of T2DM in a Northern Chin...We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-α-308G/A on the onset and development of T2DM in a Northern Chinese Han population of 213[100 type 2 diabete(T2DM) patients and 113 health control subjects] by polymerase chain reaction-restriction fragment length polymorphisum(PCR-RFLP) method.Results demonstrate the polymorphism of UCP3-55C/T,APN+45T/G,and TNF-α-308G/A related to T2DM onset and developement.And the individuals carrying UCP3-55T,APN+45G and TNF-α-308A allele had higher T2DM risk.Those results are the first report to evaluate the association of the coaction of UCP3,APN,TNF-α genes polymorphism on T2DM risk and the susceptibility of T2DM in the Northern Chinese Han population.展开更多
In the present study, we constructed a lentivirus, FIV-CMV-GFP-miR-7-3, containing the microRNA-7-3 gene and the green fluorescent protein gene, and used it to transfect human glioma U251 cells. Fluorescence microscop...In the present study, we constructed a lentivirus, FIV-CMV-GFP-miR-7-3, containing the microRNA-7-3 gene and the green fluorescent protein gene, and used it to transfect human glioma U251 cells. Fluorescence microscopy showed that 80% of U251 cells expressed green fluorescence. Real-time reverse transcription PCR showed that microRNA-7-3 RNA expression in U251 cells was significantly increased. Proliferation was slowed in transfected U251 cells, and most cells were in the G1 phase of the cell cycle. In addition, the expression of the serine/threonine protein kinase 2 was decreased. Results suggested that transfection with a lentivirus carrying microRNA-7-3 can effectively suppress epidermal growth factor receptor pathway activity in U251 cells, arrest cell cycle transition from GI phase to S phase and inhibit glioma cell growth.展开更多
Background: We investigated the immunohistochemical expression of Arp2/3 complex in 88 oral squamous cell carcinomas (OSCCs) and correlated it with the tumor type and grade. Materials and methods: This is a retrospect...Background: We investigated the immunohistochemical expression of Arp2/3 complex in 88 oral squamous cell carcinomas (OSCCs) and correlated it with the tumor type and grade. Materials and methods: This is a retrospective study of 88 cases of OSCCs (9 verrucous carcinomas, 4 carcinomas in situ, 37 well differentiated OSCCs, 32 moderately differentiated OSCCs, and 6 poorly differentiated OSCCs), stained with mouse monoclonal antibodies for Arp2 and Arp3. Staining was graded according to the extent of positivity by two observers. Results: Arp2 positivity was seen in 79 (89.77%) cases and Arp3 positivity in 78 (88.63%) cases. In positive cases, Arp2 expression was graded as (+) in 12.5%, (++) in 28.4% and (+++) in 48.86% of the cases;Arp3 was graded as (+) in 36.36%, (++) in 30.68% and (+++) in 21.59% of the cases. Conclusion: Expression of Arp2 and Arp3, indicative of the formation of the Arp2/3 complex, was seen in most OSCCs examined. Although no statistically significant correlation was found between the immunohistochemical expression of Arp2/Arp3 and tumor type or grade, the more common expression in invasive OSCCs than in non-invasive verrucous carcinomas and carcinomas in situ is indicative of its involvement in the biological behaviour of the lesions. The availability of Arp2/3 inhibitors that could be used in clinical practice warrants further study of the expression of Arp2/3 in OSCC.展开更多
AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepato...AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor (IGF-IR). Inhibitors of IGF-IR (piclopodophyllin, PPP), phosphatidyl-inositol (PI) 3-kinase (LY294002 and Wortmannin), or mitogen-activated protein (MAP) kinase (PD98059) were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS: IGF-Ⅱ stimulated cells proliferated to 2.7 (269% ± 76%) (mean ± SD) (Huh-6) and 2.1 (211% ± 85%) times (HepG2). IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% (Huh-6) and 39% ± 5% (HepG2). LY294002 and Wortmannin suppressed the cell number to 30% ± 5% (Huh-6), 44% ± 0.4% (HepG2), 49% ± 1.0% (Huh-6) and 46% ± 1.1% (HepG2), respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION: IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.展开更多
A series of 5'-phenyl-3'H-spiro[indoline-3,2'-[l,3,4]thiadiazol]-2-one analogs were synthesized and their Bcl-2 protein inhibitory activities were studied. The lead compound was originally identified using a fluore...A series of 5'-phenyl-3'H-spiro[indoline-3,2'-[l,3,4]thiadiazol]-2-one analogs were synthesized and their Bcl-2 protein inhibitory activities were studied. The lead compound was originally identified using a fluorescence polarization-based competitive binding assay. Among the 10 compounds investigated, I k showed good binding affinities to Bcl-xL and Mcl-l, with inhibition constants of 8.9 μmol/L and 3.4 μmol/L, respectively. While compound lc achieved tight binding affinities to Bcl-xL (Ki= 0.16 μmol/L), has the potential to be a new lead compound.展开更多
The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we...The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression signifi- cantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their re- sistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion mole- cules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.展开更多
BACKGROUND: Phototropism is the response a plant exhibits when it is faced with a directional blue light stimulus. Though a seemingly simple differential cell elongation response within a responding tissue that resul...BACKGROUND: Phototropism is the response a plant exhibits when it is faced with a directional blue light stimulus. Though a seemingly simple differential cell elongation response within a responding tissue that results in organ curvature, phototropism is regulated through a complex set of signal perception and transduction events that move from the plasma membrane to the nucleus. In nature phototropism is one of several plant responses that have evolved to optimize photosynthesis and growth. OBJECTIVE: In the present work we will review the state of the field with respect to the molecules and mechanisms associated with phototropism in land plants. METHODS: A systematic literature search was done to identify relevant advances in the field. Though we tried to focus on literature within the past decade (1998-present), we have discussed and cited older literature where appropriate because of context or its significant impact to the present field. Several previous review articles are also cited where appropriate and readers should seek those out. RESULTS: A total of 199 articles are cited that fulfill the criteria listed above. CONCLUSIONS: Though important numerous and significant advances have been made in our understanding of the molecular, biochemical, cell biological and physiologic mechanisms underlying phototropism in land plants over the past decade, there are many remaining unanswered questions. The future is indeed bright for researchers in the field and we look forward to the next decade worth of discoveries.展开更多
基金the National Natural Science Foundation of China (No. 30570627)
文摘Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4′,6′-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^+ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^+- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP+ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.
文摘As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.
基金Supported by the Scientific Research Foundation of Jilin Province,China(Nos.2007-0722,2008-2123,20100942)the Grants from the Developing and Reforming Community of Jilin Provinces,China(Nos.2006-1550,20080925,2010-1928)
文摘We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-α-308G/A on the onset and development of T2DM in a Northern Chinese Han population of 213[100 type 2 diabete(T2DM) patients and 113 health control subjects] by polymerase chain reaction-restriction fragment length polymorphisum(PCR-RFLP) method.Results demonstrate the polymorphism of UCP3-55C/T,APN+45T/G,and TNF-α-308G/A related to T2DM onset and developement.And the individuals carrying UCP3-55T,APN+45G and TNF-α-308A allele had higher T2DM risk.Those results are the first report to evaluate the association of the coaction of UCP3,APN,TNF-α genes polymorphism on T2DM risk and the susceptibility of T2DM in the Northern Chinese Han population.
基金supported by the Science and Technology Foundation Program of Jiangsu Province(Tumorigenic nucleostemin genes and adenovirus-based RNA interference targeting to brain tumor stem cell the rapy),No.BK2007072
文摘In the present study, we constructed a lentivirus, FIV-CMV-GFP-miR-7-3, containing the microRNA-7-3 gene and the green fluorescent protein gene, and used it to transfect human glioma U251 cells. Fluorescence microscopy showed that 80% of U251 cells expressed green fluorescence. Real-time reverse transcription PCR showed that microRNA-7-3 RNA expression in U251 cells was significantly increased. Proliferation was slowed in transfected U251 cells, and most cells were in the G1 phase of the cell cycle. In addition, the expression of the serine/threonine protein kinase 2 was decreased. Results suggested that transfection with a lentivirus carrying microRNA-7-3 can effectively suppress epidermal growth factor receptor pathway activity in U251 cells, arrest cell cycle transition from GI phase to S phase and inhibit glioma cell growth.
文摘Background: We investigated the immunohistochemical expression of Arp2/3 complex in 88 oral squamous cell carcinomas (OSCCs) and correlated it with the tumor type and grade. Materials and methods: This is a retrospective study of 88 cases of OSCCs (9 verrucous carcinomas, 4 carcinomas in situ, 37 well differentiated OSCCs, 32 moderately differentiated OSCCs, and 6 poorly differentiated OSCCs), stained with mouse monoclonal antibodies for Arp2 and Arp3. Staining was graded according to the extent of positivity by two observers. Results: Arp2 positivity was seen in 79 (89.77%) cases and Arp3 positivity in 78 (88.63%) cases. In positive cases, Arp2 expression was graded as (+) in 12.5%, (++) in 28.4% and (+++) in 48.86% of the cases;Arp3 was graded as (+) in 36.36%, (++) in 30.68% and (+++) in 21.59% of the cases. Conclusion: Expression of Arp2 and Arp3, indicative of the formation of the Arp2/3 complex, was seen in most OSCCs examined. Although no statistically significant correlation was found between the immunohistochemical expression of Arp2/Arp3 and tumor type or grade, the more common expression in invasive OSCCs than in non-invasive verrucous carcinomas and carcinomas in situ is indicative of its involvement in the biological behaviour of the lesions. The availability of Arp2/3 inhibitors that could be used in clinical practice warrants further study of the expression of Arp2/3 in OSCC.
基金Supported by the Japan Society for the Promotion of Science (JSPS) (16590577) and the Kawano Masanori Memorial Foundation for Promotion of Pediatrics (15-6)
文摘AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor (IGF-IR). Inhibitors of IGF-IR (piclopodophyllin, PPP), phosphatidyl-inositol (PI) 3-kinase (LY294002 and Wortmannin), or mitogen-activated protein (MAP) kinase (PD98059) were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS: IGF-Ⅱ stimulated cells proliferated to 2.7 (269% ± 76%) (mean ± SD) (Huh-6) and 2.1 (211% ± 85%) times (HepG2). IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% (Huh-6) and 39% ± 5% (HepG2). LY294002 and Wortmannin suppressed the cell number to 30% ± 5% (Huh-6), 44% ± 0.4% (HepG2), 49% ± 1.0% (Huh-6) and 46% ± 1.1% (HepG2), respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION: IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.
文摘A series of 5'-phenyl-3'H-spiro[indoline-3,2'-[l,3,4]thiadiazol]-2-one analogs were synthesized and their Bcl-2 protein inhibitory activities were studied. The lead compound was originally identified using a fluorescence polarization-based competitive binding assay. Among the 10 compounds investigated, I k showed good binding affinities to Bcl-xL and Mcl-l, with inhibition constants of 8.9 μmol/L and 3.4 μmol/L, respectively. While compound lc achieved tight binding affinities to Bcl-xL (Ki= 0.16 μmol/L), has the potential to be a new lead compound.
基金Supported by the Doctor Initiation Foundation of Zhengzhou University
文摘The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression signifi- cantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their re- sistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion mole- cules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.
文摘BACKGROUND: Phototropism is the response a plant exhibits when it is faced with a directional blue light stimulus. Though a seemingly simple differential cell elongation response within a responding tissue that results in organ curvature, phototropism is regulated through a complex set of signal perception and transduction events that move from the plasma membrane to the nucleus. In nature phototropism is one of several plant responses that have evolved to optimize photosynthesis and growth. OBJECTIVE: In the present work we will review the state of the field with respect to the molecules and mechanisms associated with phototropism in land plants. METHODS: A systematic literature search was done to identify relevant advances in the field. Though we tried to focus on literature within the past decade (1998-present), we have discussed and cited older literature where appropriate because of context or its significant impact to the present field. Several previous review articles are also cited where appropriate and readers should seek those out. RESULTS: A total of 199 articles are cited that fulfill the criteria listed above. CONCLUSIONS: Though important numerous and significant advances have been made in our understanding of the molecular, biochemical, cell biological and physiologic mechanisms underlying phototropism in land plants over the past decade, there are many remaining unanswered questions. The future is indeed bright for researchers in the field and we look forward to the next decade worth of discoveries.