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1.
Physiol Plant ; 167(4): 564-584, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30561011

RESUMO

Abrupt drought-flood alternation (T1) is a meteorological disaster that frequently occurs during summer in southern China and the Yangtze river basin, often causing a significant loss of rice production. In this study, the response mechanism of yield decline under abrupt drought-flood alternation stress at the panicle differentiation stage was analyzed by looking at the metabolome, proteome as well as yield and physiological and biochemical indexes. The results showed that drought and flood stress caused a decrease in the yield of rice at the panicle differentiation stage, and abrupt drought-flood alternation stress created a synergistic effect for the reduction of yield. The main reason for the decrease of yield per plant under abrupt drought-flood alternation was the decrease of seed setting rate. Compared with CK0 (no drought and no flood), the net photosynthetic rate and soluble sugar content of T1 decreased significantly and its hydrogen peroxidase, superoxide dismutase, peroxidase activity increased significantly. The identified differential metabolites and differentially expressed proteins indicated that photosynthesis metabolism, energy metabolism pathway and reactive oxygen species response have changed strongly under abrupt drought-flood alteration stress, which are factors that leads to the rice grain yield reduction.

2.
Exp Cell Res ; 360(2): 81-93, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28870599

RESUMO

Immortalized human hepatocytes (IHH) could provide an unlimited supply of hepatocytes, but insufficient differentiation and phenotypic instability restrict their clinical application. This study aimed to determine the role of hepatocyte nuclear factor 4A (HNF4A) in hepatic differentiation of IHH, and whether encapsulation of IHH overexpressing HNF4A could improve liver function and survival in rats with acute liver failure (ALF). Primary human hepatocytes were transduced with lentivirus-mediated catalytic subunit of human telomerase reverse transcriptase (hTERT) to establish IHH. Cells were analyzed for telomerase activity, proliferative capacity, hepatocyte markers, and tumorigenicity (c-myc) expression. Hepatocyte markers, hepatocellular functions, and morphology were studied in the HNF4A-overexpressing IHH. Hepatocyte markers and karyotype analysis were completed in the primary hepatocytes using shRNA knockdown of HNF4A. Nuclear translocation of ß-catenin was assessed. Rat models of ALF were treated with encapsulated IHH or HNF4A-overexpressing IHH. A HNF4A-positive IHH line was established, which was non-tumorigenic and conserved properties of primary hepatocytes. HNF4A overexpression significantly enhanced mRNA levels of genes related to hepatic differentiation in IHH. Urea levels were increased by the overexpression of HNF4A, as measured 24h after ammonium chloride addition, similar to that of primary hepatocytes. Chromosomal abnormalities were observed in primary hepatocytes transfected with HNF4A shRNA. HNF4α overexpression could significantly promote ß-catenin activation. Transplantation of HNF4A overexpressing IHH resulted in better liver function and survival of rats with ALF compared with IHH. HNF4A improved hepatic differentiation of IHH. Transplantation of HNF4A-overexpressing IHH could improve the liver function and survival in a rat model of ALF.


Assuntos
Diferenciação Celular/genética , Fator 4 Nuclear de Hepatócito/fisiologia , Hepatócitos/fisiologia , Hepatócitos/transplante , Falência Hepática Aguda/terapia , Fígado/fisiologia , Adulto , Animais , Linhagem Celular Transformada , Sobrevivência Celular/genética , Células Cultivadas , Hepatócitos/patologia , Humanos , Falência Hepática Aguda/genética , Falência Hepática Aguda/patologia , Transplante de Fígado/métodos , Masculino , Ratos , Ratos Sprague-Dawley
3.
Cancer Biol Ther ; 17(5): 558-65, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27124543

RESUMO

Mesenchymal stem cells (MSCs) hold promise as cellular vehicles for the delivery of therapeutic gene products because they can be isolated, expanded, and genetically modified in vitro and possess tumor-oriented homing capacity in vivo. (1) Hepatocyte nuclear factor 4α (HNF4α) is a dominant transcriptional regulator of hepatocyte differentiation and hepatocellular carcinogenesis (HCC). (2,3) We have previously demonstrated that overexpression of HNF4α activates various hepatic-specific genes and enhances MSC differentiation. (4) However, the extent that overexpression of HNF4α in MSCs influences HCC progression has yet to be examined. Here we sought to investigate what effect MSCs overexpressing HNF4α (MSC-HNF4α) have on human hepatoma cells in vitro and in vivo. Conditioned medium collected from in vitro MSC-HNF4α cultures significantly inhibited hepatoma cell growth and metastasis compared with controls. Additionally, nude mice administered MSC-HNF4α exhibited significantly smaller tumors compared with controls in vivo. Immunoblot analysis of HCC cells treated with MSC-HNF4α displayed downregulated ß-catenin, cyclinD1, c-Myc, MMP2 and MMP9. Taken together, our results demonstrate that MSC-HNF4α inhibits HCC progression by reducing hepatoma cell growth and metastasis through downregulation of the Wnt/ß-catenin signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Fatores Nucleares de Hepatócito/metabolismo , Neoplasias Hepáticas/genética , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt/genética , Animais , Carcinoma Hepatocelular/patologia , Proliferação de Células , Regulação para Baixo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Transfecção
4.
World J Gastroenterol ; 21(21): 6582-90, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26074696

RESUMO

AIM: To investigate the effects of transplantation of insulin-producing cells (IPCs) in the treatment of diabetic rats after 90% pancreatectomy. METHODS: Human umbilical cord mesenchymal stem cells (UCMSCs) were isolated and induced into IPCs using differentiation medium. Differentiated cells were examined by dithizone (DTZ) staining, reverse transcription-polymerase chain reaction (RT-PCR), and real-time RT-PCR. C-peptide release, both spontaneously and after glucose challenge, was measured by ELISA. IPCs were then transplanted into Sprague-Dawley rats after 90% pancreatectomy and blood glucose levels and body weight were measured. RESULTS: The differentiated cells were positive for DTZ staining and expressed pancreatic ß-cell related genes. C-peptide release by the differentiated cells increased after glucose challenge (380.6 ± 15.32 pmol/L vs 272.4 ± 15.32 pmol/L, P < 0.05). Further, in the cell transplantation group, blood sugar levels were significantly lower than in the sham group 2 wk after transplantation (18.7 ± 2.5 mmol/L vs 25.8 ± 1.25 mmol/L, P < 0.05). Glucose tolerance tests showed that 45 min after intraperitoneal glucose injection, blood glucose levels were significantly lower on day 56 after transplantation of IPCs (12.5 ± 4.7 mmol/L vs 42.2 ± 9.3 mmol/L, P < 0.05). CONCLUSION: Our results show that UCMSCs can differentiate into islet-like cells in vitro under certain conditions, which can function as IPCs both in vivo and in vitro.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Diabetes Mellitus Experimental/cirurgia , Diabetes Mellitus Tipo 1/cirurgia , Células Secretoras de Insulina/transplante , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Pancreatectomia , Animais , Glicemia/metabolismo , Peso Corporal , Peptídeo C/metabolismo , Diferenciação Celular , Proliferação de Células , Forma Celular , Células Cultivadas , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/genética , Regulação da Expressão Gênica , Teste de Tolerância a Glucose , Humanos , Células Secretoras de Insulina/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos Sprague-Dawley , Fatores de Tempo , Cordão Umbilical/citologia , Geleia de Wharton/citologia
5.
J Genet ; 92(2): 281-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23970084

RESUMO

The study of 1000-grain weight (TGW) and percentage of grains with chalkiness (PGWC) is very important in rice. In this study, a set of introgression lines (ILs), derived from Sasanishiki/Habataki with Sasanishiki as the recurrent parent, were used to detect correlations and quantitative trait loci (QTL) on TGW and PGWC in two different environments. Phenotypic correlation analysis showed that there was no significant correlation between TGW and PGWC in both environments, which indicated that the linkage of TGW and PGWC traits could be broken via suitable population. A total of 20 QTL were detected in both environments, nine QTL for 1000-paddy-grain weight (PTGW), five QTL for 1000-brown-grain weight (BTGW) and six QTL for percentage of grains with chalkiness (PGWC). Moreover, five QTL, qPTGW3, qPTGW8.2, qPTGW11.1 for PTGW and qPGWC1.1, qPGWC1.2 for PGWC, were stably expressed in both environments. Phenotypic values were significantly different (P < 0.01) between the introgression lines carrying these five QTL alleles and the genetic background parent, Sasanishiki. The introgression lines carrying these QTL also represent a useful genetic resource in the context of rice yield and quality improvement via a design-breeding approach.


Assuntos
Mapeamento Cromossômico , Oryza/crescimento & desenvolvimento , Oryza/genética , Locos de Características Quantitativas , Cruzamentos Genéticos , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Ligação Genética , Valor Nutritivo/genética , Fenótipo , Melhoria de Qualidade
6.
Tumour Biol ; 34(4): 2309-13, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23568706

RESUMO

CIP2A has been regarded as a novel potential therapeutic target for multiple cancers. The aim of this study was to detect CIP2A expression in pancreatic ductal adenocarcinoma (PDA) and to analyze its association with prognosis of PDA patients. The expression of CIP2A and three epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin, and vimentin) was examined in 96 PDA tissue samples by immunohistochemistry. Fifty-four cases (56.3 %) were defined as positive for CIP2A expression. Immunohistochemistry showed that CIP2A expression was correlated with poor tumor differentiation, TNM stage, and lymph node metastasis. Kaplan-Meier survival analysis showed that patients with CIP2A-positive expression showed lower overall survival rate than those with CIP2A-negative expression. Multivariate analysis showed that CIP2A expression was an independent prognostic factor for PDA patients. Furthermore, positive expression of CIP2A was strongly associated with loss of the epithelial marker E-cadherin and acquisition of the expression of the mesenchymal markers N-cadherin and vimentin. These findings suggest that CIP2A might promote EMT and progression in PDA, and thus may be a potential therapeutic target for patients with PDA.


Assuntos
Autoantígenos/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Transição Epitelial-Mesenquimal , Proteínas de Membrana/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidade , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Autoantígenos/biossíntese , Biomarcadores Tumorais/metabolismo , Caderinas/biossíntese , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Metástase Linfática , Masculino , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pâncreas/metabolismo , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Prognóstico , Sobrevida , Taxa de Sobrevida , Vimentina/biossíntese
7.
Med Oncol ; 29(3): 2251-60, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21773820

RESUMO

Arsenic trioxide (ATO) has shown anticancer activity against a variety of solid tumor models through induction of apoptosis, promotion of cellular differentiation, and inhibition of cellular invasive ability. The present study investigated the role of ceramide in regulating the invasive activity of hepatoma carcinoma HCCLM3 cells during ATO treatment. We found that ATO treatment inhibited HCCLM3 cell invasion and downregulated matrix metalloproteinase-9 (MMP-9) protein levels in a concentration-dependent manner. ATO also dose dependently induced the generation and accumulation of ceramide in HCCLM3 cells. Blockage of intracellular ceramide production through the inhibition of de novo ceramide synthesis or the hydrolysis of sphingomyelin increased the invasive ability and upregulated MMP-9 protein levels. The findings of this study indicated that ATO induced ceramide production through de novo ceramide synthesis and the hydrolysis of sphingomyelin and suggested that ceramide accumulation in response to ATO stimuli may play an important role in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Arsenicais/farmacologia , Carcinoma Hepatocelular/metabolismo , Ceramidas/biossíntese , Neoplasias Hepáticas/metabolismo , Óxidos/farmacologia , Trióxido de Arsênio , Western Blotting , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Metaloproteinase 9 da Matriz/biossíntese , Microscopia de Fluorescência , Invasividade Neoplásica/patologia , Esfingomielina Fosfodiesterase/metabolismo
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3087-91, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242523

RESUMO

In order to understand the characteristics of atmospheric heavy metal deposition in Harbin City, 46 deposition samples were collected which were taken using bulk deposition samplers during the period of 2008-2009 (about 365 days). The samples were analyzed for heavy metal concentration by atomic fluorescence spectrometry (AFS) and inductively coupled plasma-atomic spectrometry (ICP-AES). The deposition flux was calculated. Sources analysis was made by the method of principal component analysis (PCA), Pearsons and enrichment factor (EF). The following points can be gained through multivariate analysis. Mn and Co are mostly from natural sources while the others may be brought by coal dust, vehicle emissions and metal smelting.

9.
Zhonghua Wai Ke Za Zhi ; 43(15): 1014-6, 2005 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-16194364

RESUMO

OBJECTIVE: To investigate the way of nuclear factor kappa B (NF-kappaB) activation and the mechanism of NF-kappaB-promoted proliferation in estrogen receptor (ER)-negative breast cancer cells. METHODS: The protein of IkappaB kinase alpha (IKKalpha) was measured by Western blot and the influence on cell-cycle was assayed by flow cytometry (FCM). RESULTS: The IKKalpha was tested higher in three ER-negative breast cancer cell lines than in MCF-7. The influence caused by epidermal growth factor (EGF), tumor necrosis factor (TNF)-alpha and E(2) to tumor cells' proliferation was tested. EGF could remarkably enhance cyclin D(1) expression about 83% more in EGF group than that in control group and proliferation index from 0.22 to 0.31 (P < 0.01). On the other hand, TNF-alpha inhibited cyclin D(1) expression. Protein kinase C inhibitor, Go6976, could peculiarly prevent NF-kappaB over-expression caused by EGF. The cell-cycle was assayed by FCM in phase G(0)/G(1) 69.36% and in phase S 22.77% when adding EGF and in phase G(0)/G(1) 91.54% and in phase S 7.81% when adding EGF and Go6976. The proliferation index decreased from 0.31 to 0.09 (P < 0.01). CONCLUSIONS: EGF-EGFR pathway can provide ER-negative breast cancer cells the signal for the autonomous growth. This signal promoted tumor cells' proliferation is transmitted by activating NF-kappaB and expressing more cyclin D(1). In this pathway, NF-kappaB play an important role as signal transmitting. The strategy to NF-kappaB activating may provide new way to treat ER-negative breast cancers.


Assuntos
Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , NF-kappa B/metabolismo , Transdução de Sinais , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Carbazóis/farmacologia , Ciclina D1/biossíntese , Fator de Crescimento Epidérmico/farmacologia , Estradiol/farmacologia , Feminino , Humanos , Quinase I-kappa B/metabolismo , Indóis/farmacologia , NF-kappa B/fisiologia , Receptores Estrogênicos/metabolismo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia
10.
Environ Geochem Health ; 26(1): 81-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15214616

RESUMO

China is a very large developing country covering vast territories and having a complex natural environment. It has an enormous population and numerous endemic diseases. The total population of China is 14 x 10(8) of which 3 x 10(3) live in endemic disease-affected areas and 0.48 x 10(3) suffer from these diseases. The distribution of the endemic diseases has obvious geographical characteristics. Among the most harmful and widely distributed of the endemic diseases are Kaschin-Beck disease, Keshan disease, iodine deficiency, endemic fluorosis and hepatic carcinoma. The geographical environments have a close relationship to endemic diseases and are influenced by climate, geology, landform, soil, food and drinking water. Drinking water is the key issue, since polluted water, or water lacking in or having an excess of certain minerals and elements, as well as water containing certain organic components, has been shown to be harmful to human health. Research has shown that some diseases can be reduced or eliminated by paying attention to the way drinking water is obtained, as well as by improving the nutritional values of the food by eliminating negative components. Fifty years of research has already gone into this subject and there is still much research to be done. This paper puts forth a model of health problems related to geographical environment and the importance of continued research in this field.


Assuntos
Doenças Endêmicas/classificação , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Saúde Pública , China , Clima , Países em Desenvolvimento , Dieta , Grão Comestível , Geografia , Humanos , Modelos Biológicos , Mortalidade , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Fatores de Risco , Abastecimento de Água
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