Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Mais filtros

Base de dados
Tipo de estudo
Intervalo de ano de publicação
Int J Ophthalmol ; 12(10): 1539-1547, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637188


AIM: To explore the effect of Obtusifolin on retinal pigment epithelial cell growth under hypoxia. METHODS: In vitro chemical hypoxia model of ARPE-19 cells was established using cobalt chloride (CoCl2). Cell viability was tested by cell counting kit-8 (CCK-8) assay. Western blot and real-time quantitative polymerase chain reaction were applied to detect proteins and mRNAs respectively. Flow cytometry was used to examine the cell cycle. Secretion of vascular endothelial growth factor (VEGF) was tested by using enzyme linked immunosorbent assay (ELISA). RESULTS: Under the chemical hypoxia model established by CoCl2, hypoxia inducible factor-1α (HIF-1α) mRNA and protein levels was up-regulated. Cell viability was increased and the proportion of S phase was higher. Obtusifolin could reduce cell viability under hypoxic conditions and arrest cells in G1 phase. Obtusifolin reduced the expression of Cyclin D1 and proliferating cell nuclear antigen (PCNA) in the hypoxic environment and increased the expression of p53 and p21. The levels of VEGF, VEGFR2 and eNOS proteins and mRNA were significantly increased under hypoxia while Obtusifolin inhibited the increasing. CONCLUSION: Obtusifolin can inhibit cell growth under hypoxic conditions and down-regulate HIF-1/VEGF/eNOS secretions in ARPE-19 cells.

Hum Immunol ; 75(12): 1232-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25300998


Patients with autoimmune and allergic diseases frequently present with reduced numbers and functionally impaired regulatory T cells (Tregs) and/or tolerogenic dendritic cells (tDCs). tDC-mediated regulation of Treg proliferation (numbers) and activation is crucial to establishing and maintaining an appropriate level of immune tolerance. Colonic colonization of Clostridium spp. is associated with accumulation of Tregs, which inhibits development of inflammatory lesions. To investigate whether infection with the Clostridium leptum sp. can specifically induce Tregs and/or tDCs bone marrow-derived dendritic cells were cultured in the presence or absence of C. leptum then co-cultured with CD4(+)CD25(-) T cells or not. Changes in tDC numbers, Treg numbers, percentages of T cell subsets, and expression of cytokines related to Tregs (IL-10 and transforming growth factor-beta (TGF-ß1)), DCs (IL-12p40 and IL-6) and effector T cells (IFN-γ, IL-4, IL-5, IL-13, and IL-17A) were measured. In the co-culture system, C. leptum-stimulated tDCs were able to increase the percentage and total number of Tregs attenuate activation of T helper cells (Th1, Th2, and Th17), and decrease the amount of secreted IL-4, IL-5, IL-13, IFN-γ and IL-17A. Thus, C. leptum exposure can induce the tDC-mediated stimulation of Tregs while disrupting the immune inflammatory response mediated by Th1, Th2 and Th17 cells.

Clostridium/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Intestinos/microbiologia , Linfócitos T Reguladores/imunologia , Animais , Células da Medula Óssea/imunologia , Células Cultivadas , Citocinas/biossíntese , Citocinas/metabolismo , Feminino , Inflamação/imunologia , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
Zhonghua Yan Ke Za Zhi ; 49(9): 783-8, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24330926


OBJECTIVE: To investigate the prevalence and causes of blindness and moderate and severe visual impairment among adults aged ≥ 50 years in Longyao County, Hebei Province, China. METHODS: It was a population-based cross-section study.Geographically defined cluster sampling was used in randomly selecting 5527 individuals aged ≥ 50 years in Longyao County. The survey was preceded by a pilot study where operational methods were refined and quality assurance evaluation was carried out. All participants were enumerated through village registers followed door-to-door visits.Eligible individuals were invited to receive visual acuity measurement and eye examination. Prevalence of blindness and moderate and severe visual impairment was calculated according to different age, gender or education. And the reasons of blindness were analyzed.Statistical analyses were performed using Stata/SE Statistical Software, release 9.0. Chi-square test was used to investigate the association of age, gender and education with presenting and best corrected visual acuity. RESULTS: Five thousands five hundreds and twenty-seven individuals were enumerated and 5051 persons were examined, the response rate was 91.39%. Based on the criteria of World Health Organization visual impairment classification in 1973, the prevalence of blindness and moderate and severe visual impairment defined as best corrected visual acuity was 1.05% (53/5051) and 3.46% (175/5051) respectively. The prevalence of blindness and moderate and severe visual impairment defined as presenting visual acuity was 1.48% (75/5051) and 7.94% (401/5051) respectively. The prevalence of blindness and moderate and severe visual impairment was higher in aged (trend χ(2) = 897.27, P = 0.000) , female (χ(2) = 30.32, P = 0.000), illiterate (trend χ(2) = 83.20, P = 0.000) persons. Cataract was still the first leading cause of blindness. Un-corrected refractive error also was the main cause of visual impairment. CONCLUSIONS: The prevalence of blindness and moderate and severe visual impairment is relatively lower among China Nine Province Survey. The first leading cause of blindness and visual impairment is still cataract.

Cegueira/epidemiologia , Transtornos da Visão/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Catarata/epidemiologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
Environ Toxicol Pharmacol ; 22(3): 283-91, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21783722


Cigarette smoking is a risk factor in the developing of various cancers including breast tumors. There are more than 60 chemical carcinogens in the cigarette smoke; 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) being one of the strongest tobacco-specific carcinogens. In this study, we demonstrated that NNK rapidly activated ERK1 and ERK2 MAP kinases and stimulated proliferation in human normal mammary epithelial cells. MEK1/2 specific inhibitor UO126 completely blocked NNK-induced ERK1/2 activation and cell proliferation, whereas nicotinic receptor nAchR antagonist mecamylamine partially and the selective α(7)-nAchR antagonist α-bungarotoxin essentially inhibited the NNK-induced ERK1/2 activation and cell proliferation. Surprisingly, receptor tyrosine kinase inhibitor genistein, the selective ß(1)-adrenergic antagonist atenolol, and the selective ß(2)-adrenergic antagonist ICI118.551 had a strong inhibitory effect on ERK1/2 activation and cell proliferation induced by NNK. These results suggest that there are at least two different routes in activating ERK1/2 by NNK. One is through nicotinic receptor α(7)-nAchR to MEK1/2; the other is from ß(1)/ß(2)-adrenergic transactivation of tyrosine kinase containing receptor(s) to MEK1/2. In human cancer mammary epithelial cell lines, we found that ERK MAPK signaling pathway was deregulated: (1) ERK1/2 was constitutively activated at various levels; (2) ERK1/2 was further significantly activated in response to NNK induction; (3) UO126 partially or totally failed to inhibit ERK1/2 activation induced by NNK; (4) The expression levels of ERK1/2 in the cancer cell lines were much higher than those in the normal mammary epithelial cells. The tobacco-specific carcinogen NNK showed a strong proliferative effect on human normal and cancer mammary epithelial cells; the proliferation multitudes of these cells are well correlated with the activation levels of ERK1/2 MAP kinases.