Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(5): 760-6, 800, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25341335

RESUMO

OBJECTIVE: To study the effects of (E)-2-(4-bromophenyl)-1-(3, 4-dihydroxyphenyl) ethanone oxime (BDEO) on the proliferation and activation of the mice' s splenic lymphocytes and the peripheral blood lymphocytes induced by Concanavalin A (Con A) in vitro and in vivo, and its molecular mechanism. METHODS: During the lymphocyte proliferation and activation induced by Con A in vitro, MTT and cell counting were used to detect the transformation rates and survival rates of lymphocytes, and ELISA was used to measure the activity of caspase-9; moreover, the levels of Bax, Bcl-2 and caspase-3 were determined by Western blot, in order to observe the effects of BDEO on cell proliferation and activation. The effects of administration of Con A [15 mg/(kg x d)] and BDEO [(3, 6 mg/(kg x d)] by intraperitoneal injection on transformation rates of spleen cells and peripheral blood lymphocyte, as well as phagocytosis rate of peritoneal macrophages in mice were also observed in vivo. RESULTS: 0.3-1 micromol/L BDEO significantly inhibited the transformation rates and growth of mice lymphocyte (P < 0.05). The activity of caspase-9 and the levels of mitochondrial pro-apoptotic protein Bax and Bak gradually increased, then decreased as the BDEO continually accumulated. Anti-apoptotic protein Bcl-2 as well as mitochondrial Cyt C levels first decreased then increased gradually, and cytoplasmic Cyt C, cleaved caspase-9 and cleaved caspase-3 levels showed firstly a increase, then decrease gradually. Additionally, administration of BDEO by intraperitoneal injection significantly inhibited proliferation of spleen lymphocytes and peripheral blood lymphocyte, as well as phagocytosis of peritoneal macrophagesin in mice. CONCLUSION: BDEO might regulate the proliferation and activation of lymphocytes through activation of caspase-3 mainly via a mitochondrial intrinsic pathway; the inhibiting effect on the proliferation and transformation rate of lymphocytes was significant when the concentration of BDEO was relatively low; as the concentration accumulated increasingly, the inhibiting effect reduced. The results indicated that BDEO has immunosuppressive activity.


Assuntos
Benzoína/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Oximas/farmacologia , Animais , Benzoína/farmacologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Concanavalina A , Camundongos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Baço/citologia , Proteína X Associada a bcl-2/metabolismo
2.
Acta Pharmacol Sin ; 35(7): 945-56, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24989254

RESUMO

AIM: Lund human mesencephalic (LUHMES) cells can be differentiated to post-mitotic cells with biochemical, morphological and functional features of dopaminergic (DAergic) neurons. Given the limited scale of primary DAergic neuron culture, we developed differentiated LUHMES cell-based cytotoxicity assays for identifying neuroprotective agents for Parkinson's disease (PD). METHODS: LUHMES cells were incubated in a differentiation medium containing cAMP and GDNF for 6 d, and then differentiated cells were treated with MPP(+) or infected with baculovirus containing α-synuclein. Cytotoxicity was determined by measuring intracellular ATP levels and caspase 3/7 activity in the cells. DAergic neuron-specific marker protein and mRNA levels in the cells were analyzed using Western blotting and RT-PCR, respectively. RESULTS: LUHMES cells grew extensive neurites and became post-mitotic neuron-like cells during differentiation period, and three DAergic neuron markers TH, DAT and Nurr1 exhibited different expression profiles. MPP(+) dose-dependently reduced ATP levels in the cells with an IC50 value of 65 µmol/L. MPP(+) (80 µmol/L) significantly increased caspase 3/7 activity in the cells. Both the CDK inhibitor GW8510 and the GSK3ß inhibitor SB216763 effectively rescued MPP(+)-induced reduction of ATP levels with EC50 values of 12 and 205 nmol/L, respectively. Overexpression of α-synuclein also significantly decreased intracellular ATP levels and increased caspase 3/7 activity in the cells. GW8510 and SB216763 effectively rescued α-synuclein overexpression-induced reduction of ATP levels, whereas GW8510, but not SB216763, ameliorated α-synuclein overexpression-induced increase of caspase 3/7 activity. CONCLUSION: MPP(+)- and α-synuclein overexpression-induced cytotoxicity of differentiated LUHMES cells may serve as good alternative systems for identifying neuroprotective compounds for PD.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Indóis/farmacologia , Maleimidas/farmacologia , Mesencéfalo/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , 1-Metil-4-fenilpiridínio , Morte Celular/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Humanos , Neurônios/citologia , Neurônios/metabolismo , Doença de Parkinson/genética , Doença de Parkinson Secundária/induzido quimicamente , alfa-Sinucleína/genética
3.
Zhonghua Nei Ke Za Zhi ; 52(8): 651-3, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24199879

RESUMO

OBJECTIVE: To investigate the prevalence of occupational asthma, airway inflammation and analyze the risk factors for workers exposed to isocyanates. METHODS: A cross-sectional study was applied. Totally 429 isocyanates exposed workers were surveyed and the prevalence of occupational asthma and airway inflammation situation were examined by questionnaire, physical examination and laboratory tests. Multivariate logistic regression was applied to analyze the possible risk factors of isocyanate-induced occupational asthma. RESULTS: (1) A total of 366 patients with complete data were included in the study, and finally 11 cases were diagnosed as isocyanate-induced occupational asthma with a prevalence of 3.0%. (2) Neutrophil percentage in the induced sputum of occupational asthma increased significantly [42.00% (34.00%-55.00%) before work and 59.00% (51.00%-70.00%) after work (Z = -2.940. P < 0.05)]. (3) Length of service (OR = 3.096, P = 0.025) and rhinitis (OR = 1.901, P = 0.008) were independent dangerous factors, and protective measures (OR = 0.074, P = 0.015) was protective factors to isocyanate-induced occupational asthma. CONCLUSIONS: Neutrophilic inflammation can be triggered by isocyanate exposure. Regular health examinations, effective protective measures can reduce the prevalence of isocyanate-induced occupational asthma.


Assuntos
Asma Ocupacional/etiologia , Isocianatos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
4.
Bioresour Technol ; 136: 730-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23558183

RESUMO

A conventional trickle bed reactor and its modified type both packed with Ca/Al composite oxide-based alkaline catalysts were studied for biodiesel production by transesterification of rapeseed oil and methanol. The effects of the methanol usage and oil flow rate on the FAME yield were investigated under the normal pressure and methanol boiling state. The oil flow rate had a significant effect on the FAME yield for the both reactors. The modified trickle bed reactor kept over 94.5% FAME yield under 0.6 mL/min oil flow rate and 91 mL catalyst bed volume, showing a much higher conversion and operational stability than the conventional type. With the modified trickle bed reactor, both transesterification and methanol separation could be performed simultaneously, and glycerin and methyl esters were separated additionally by gravity separation.


Assuntos
Álcalis/farmacologia , Alumínio/farmacologia , Biocombustíveis , Reatores Biológicos/microbiologia , Cálcio/farmacologia , Óxidos/farmacologia , Óleos de Plantas/metabolismo , Catálise/efeitos dos fármacos , Esterificação/efeitos dos fármacos , Ésteres/análise , Ácidos Graxos Monoinsaturados , Óleo de Brassica napus
5.
Bioresour Technol ; 128: 305-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23196252

RESUMO

A solid Ca/Al composite oxide-based alkaline catalyst containing Ca(12)Al(14)O(33) and CaO was prepared by chemical synthesis and thermal activation from sodium aluminate solution and calcium hydroxide emulsion. The effect of calcination temperatures ranging from 120 °C to 1000 °C on activity of the catalyst was investigated. The catalyst calcined at 600 °C showed the highest activity with >94% yield of fatty acid methyl esters (i.e. biodiesel) when applied to the transesterification of rapeseed oil at a methanol:oil molar ratio of 15:1 at 65 °C for 3h. Structure and properties of the catalyst were studied and the characterizations with XRD, TGA, FTIR, BET, and SEM demonstrated that the performance of the catalyst was closely related to its specific surface area and crystalline structure. In particular, the generation of crystalline Ca(12)Al(14)O(33) improved the catalytic activity due its synergistic effect with CaO.


Assuntos
Álcalis/química , Óxido de Alumínio/química , Biocombustíveis/análise , Compostos de Cálcio/química , Óxidos/química , Óleos de Plantas/química , Catálise , Ácidos Graxos Monoinsaturados , Óleo de Brassica napus , Temperatura
6.
Zhonghua Yan Ke Za Zhi ; 49(11): 1014-9, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24513004

RESUMO

OBJECTIVE: To study the effect of chloride channel on proliferation induced by basic-fibroblast growth factor (bFGF) in human lens epithelial cells HLE B-3 (LEC). METHODS: HLE B-3 cells at Logarithmic growth phase were incubated in the 6 or 96 well plate overnight and the proliferation was induced by 10 µg/L bFGF. The cells were divided into bFGF group treated with bFGF and the blank control group with the regular cells culture. LEC were treated with different concentrations of chloride channel inhibitors: 5-nitro-2-[3-phenylpropylamino] benzoic acid (NPPB) at 50, 100, 150 µmol/L and 4 , 4'-2 diisothiocyanostilbene-2, 2' -disulfonic acid (DIDS) at 10, 50, 100 µmol/L with bFGF or without bFGF in 10% serum for 24, 48, 72 hours. The cell viability and the drug toxicity were detected by CCK-8 colorimetric assay. The expression of proliferating cell nuclear antigen (Ki-67) of LEC treated with NPPB or DIDS were observed by immunocytochemistry staining assay. The phase change of cell cycle was examined by flow cytometry. Each experiment group and control group were compared using two-way ANOVA, further pairwise comparisons using LSD-t test or by the Independent-Samples t test. RESULTS: 10 µg/L bFGF induced LEC proliferation and the values of A stage were gradually declined with the increase of chloride channel inhibitors' concentrations and time at 24 hours, 48 hours and 72 hours (bFGF+NPPB group: Ftime = 305.28, Fconcentrations = 18.76, P = 0.000;bFGF+ DIDS group:Ftime = 94.44, Fconcentrations = 24.42, P = 0.000). Different concentrations of chloride channel inhibitor reduced the values of a stage with 10 µg/L bFGF in a dose- and time-dependent manner. The expression of Ki-67 was significantly lowered compared with the bFGF group (bFGF+NPPB group: 18.32% ± 1.23%, F = 580.3, P = 0.000;bFGF+DIDS group: 11.21% ± 1.02%, F = 507.4, P = 0.000), when 150 µmol/L NPPB and 100 µmol/L DIDS with 10 µg/L bFGF were added at 48 hours. After 150 µmol/L NPPB and 100 µmol/L DIDS treatment at the 48th hour, the rate of G1 stage was significantly increased (F = 390.754, P = 0.000), where as that of S stage decreased significantly (F = 166.240, P = 0.000). CONCLUSIONS: These results indicate that chloride channel inhibitors play an important role in modulating the proliferation cycle of LEC treated with bFGF by limiting the cell at cycle S/G1 stage from dividing into S stage.


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Nitrobenzoatos/farmacologia , Linhagem Celular , Canais de Cloreto/antagonistas & inibidores , Humanos , Cristalino/citologia
7.
Artigo em Chinês | MEDLINE | ID: mdl-21126426

RESUMO

OBJECTIVE: to explore effects of airborne fine particulate matter exposure on human respiratory symptoms and pulmonary function. METHODS: one hundred and seven field traffic policemen were recruited as airborne fine particulate matter high-exposure group and one hundred and one male residents as common exposure group. The individual sampler was used to measure fine particulate matter exposure levels of the two groups. To obtain personal information, especially respiratory symptoms such as cough, sputum, etc. a questionnaire survey was used. The pulmonary ventilation function was detected: forced expiratory vital capacity (FVC), the first 1 second forced expiratory volume (FEV1.0), FVC/FEV1.0% and peak flow values (PEF), and the difference of fine particulate matter exposure level and respiratory function of the two groups was compared. RESULTS: 24 h individual average fine particulate matter exposure concentration of traffic police and residents were respectively (115.4 ± 46.17) microg/m(3) and (74.94 ± 40.09) microg/m(3), the traffic police PM2.5 exposure levels were significantly higher than the residents. In the incidence of respiratory symptoms, compared with high-exposure group and common exposure group, coughing, expectoration, throat unwell, asthma, short of breath and nose discomfort, traffic police group was higher than residents group (P < 0.05). The abnormal rate of lung ventilation function indexes, such as FVC and FEV1.0 was 25.23% and 12.15% respectively in high-exposure group, 11.88% and 2.97% in common exposure group, there was no statistical difference between two groups. Besides, the abnormal rate of FVC and FEV1.0, showed rising trend in high-exposure group with seniority. CONCLUSION: long-term higher levels of airborne fine particulate matter exposure, may impact respiratory health and impair pulmonary function.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Exposição Ocupacional , Material Particulado/efeitos adversos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Polícia , Ventilação Pulmonar , Inquéritos e Questionários
8.
Plant Cell Physiol ; 49(12): 1851-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18988636

RESUMO

Aquaporins are water channel proteins that facilitate passage of water and other small neutral molecules across biological membranes. There are usually a large number of members of this family in higher plants, which exhibit various physiological functions and are regulated in a time-specific and particular mode. We have previously shown that a rice gene, OsPIP2;7, was generally up-regulated in roots but down-regulated in shoots at the early stage of chilling stress. Here, OsPIP2;7 was cloned and proved to be an aquaporin with high activity in Xenopus oocytes. OsPIP2;7 was localized mainly in mesophyll cells of leaves. In roots it was detected in the vascular tissues, epidermis cells and exodermis cells at the elongation zone, as well as in the epidermis cells, exodermis cells and root hair at the maturation zone. Yeast cells overexpressing OsPIP2;7 showed a higher survival rate after freeze-thaw stress. Furthermore, OsPIP2;7 enhanced the transpiration rate and tolerance to low temperature when overexpressed in rice. These results indicated that OsPIP2;7 was involved in rapid water transport and maintenance of the water balance in cells, and ultimately improves the tolerance of yeast and rice to low temperature stress.


Assuntos
Aquaporinas/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Transpiração Vegetal , Aquaporinas/genética , Clonagem Molecular , Temperatura Baixa , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Osmose , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , RNA de Plantas/genética
9.
J Plant Physiol ; 165(18): 1879-88, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18707797

RESUMO

The vacuole, a multifunctional organelle of most plant cells, has very important roles in space filling, osmotic adjustment, storage and digestion. Previous researches suggested that aquaporins in the tonoplast were involved in vacuolar functions. The rice genome contains 33 aquaporin genes, 10 of which encode tonoplast intrinsic proteins (TIPs). However, the function of each individual TIP isoform and the integrated function of TIPs under various physiological conditions remain elusive. Here, five rice TIP members were characterized with water and/or glycerol transport activities using the Xenopus oocyte expression system. OsTIP1;2, OsTIP2;2, OsTIP4;1 and OsTIP5;1 possessed water transport activity. OsTIP1;2, OsTIP3;2 and OsTIP4;1 were demonstrated with glycerol transport activity. Rice TIP expression patterns under various abiotic stress conditions including dehydration, high salinity, abscisic acid (ABA) and during seed germination were investigated by real-time PCR. OsTIP1s (OsTIP1;1 and OsTIP1;2) were highly expressed during seed germination, whereas OsTIP3s (OsTIP3;1 and OsTIP3;2) were specifically expressed in mature seeds with a decrease in expression levels upon germination. The results of this research provided a functional and expression profiles of rice TIPs.


Assuntos
Aquaporinas/genética , Regulação da Expressão Gênica de Plantas , Membranas Intracelulares/metabolismo , Oryza/genética , Estresse Fisiológico/genética , Vacúolos/metabolismo , Ácido Abscísico/farmacologia , Animais , Aquaporinas/metabolismo , Transporte Biológico/efeitos dos fármacos , Desidratação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Germinação/genética , Glicerol/metabolismo , Membranas Intracelulares/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Oryza/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Salinidade , Plântula/efeitos dos fármacos , Plântula/genética , Sementes/efeitos dos fármacos , Sementes/genética , Estresse Fisiológico/efeitos dos fármacos , Vacúolos/efeitos dos fármacos , Água/metabolismo , Xenopus
10.
Cell Res ; 16(6): 599-608, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16775631

RESUMO

A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake) seedlings were chilled at 7 degrees C, followed by recovery at 28 degrees C. Based on the growth phenotype and electrolyte leakage tests, Somewake was shown to be a chilling-tolerant variety, and Wasetoitsu a chilling-sensitive one. The chilling stress reduced markedly the relative water content (RWC) of leaves, accumulative transpiration and osmotic root hydraulic conductivity (Lp) in both varieties. But when returned to 28 degrees C, the water relation balance of Somewake recovered better. The mRNA expression profile of all the 11 plasma membrane intrinsic proteins (PIPs), a subgroup of aquaporins, was subsequently determined by real-time reverse transcription (RT)-PCR with TaqMan-minor grove binder (MGB) probes derived from rice var. Nipponbare during chilling treatment and recovery. Most of the PIP genes was down-regulated at the low temperature, and recovered at the warm temperature. The relative expression of some PIPs in both Somewake and Wasetoitsu decreased in parallel during the chilling. However during the recovery, the relative expression of OsPIP1;1, OsPIP2;1, OsPIP2;7 in shoots and OsPIP1;1, OsPIP2;1 in roots were significantly higher in Somewake than Wasetoitsu. This supports the role of PIPs in re-establishing water balance after chilling conditions. We discuss the diversified roles played by members of the aquaporin PIP subfamily in plant chilling tolerance depending on aquaporin isoforms, plant tissue and the stage of chilling duration.


Assuntos
Aquaporinas/biossíntese , Temperatura Baixa , Oryza/fisiologia , Proteínas de Plantas/biossíntese , Água/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Plântula/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...