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2.
Sci Rep ; 6: 36874, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27845421

RESUMO

NBS1, also known as NBN, plays an important role in maintaining genomic stability. Interestingly, rs2735383 G > C, located in a microRNA binding site in the 3'-untranslated region (UTR) of NBS1, was shown to be associated with increased susceptibility to lung and colorectal cancer. However, the relation between rs2735383 and susceptibility to breast cancer is not yet clear. Therefore, we genotyped rs2735383 in 1,170 familial non-BRCA1/2 breast cancer cases and 1,077 controls using PCR-based restriction fragment length polymorphism (RFLP-PCR) analysis, but found no association between rs2735383CC and breast cancer risk (OR = 1.214, 95% CI = 0.936-1.574, P = 0.144). Because we could not exclude a small effect size due to a limited sample size, we further analyzed imputed rs2735383 genotypes (r2 > 0.999) of 47,640 breast cancer cases and 46,656 controls from the Breast Cancer Association Consortium (BCAC). However, rs2735383CC was not associated with overall breast cancer risk in European (OR = 1.014, 95% CI = 0.969-1.060, P = 0.556) nor in Asian women (OR = 0.998, 95% CI = 0.905-1.100, P = 0.961). Subgroup analyses by age, age at menarche, age at menopause, menopausal status, number of pregnancies, breast feeding, family history and receptor status also did not reveal a significant association. This study therefore does not support the involvement of the genotype at NBS1 rs2735383 in breast cancer susceptibility.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , MicroRNAs/metabolismo , Proteínas Nucleares/genética , Regiões 3' não Traduzidas , Alelos , Proteína BRCA1/genética , Proteína BRCA2/genética , Sítios de Ligação , Neoplasias da Mama/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Risco
3.
Invest Ophthalmol Vis Sci ; 57(9): OCT196-203, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27409473

RESUMO

PURPOSE: Posterior eye shape assessment by magnetic resonance imaging (MRI) is used to study myopia. We tested the hypothesis that optical coherence tomography (OCT), as an alternative, could measure posterior eye shape similarly to MRI. METHODS: Macular spectral-domain OCT and brain MRI images previously acquired as part of the Singapore Epidemiology of Eye Diseases study were analyzed. The right eye in the MRI and OCT images was automatically segmented. Optical coherence tomography segmentations were corrected for optical and display distortions requiring biometry data. The segmentations were fitted to spheres and ellipsoids to obtain the posterior eye radius of curvature (Rc) and asphericity (Qxz). The differences in Rc and Qxz measured by MRI and OCT were tested using paired t-tests. Categorical assignments of prolateness or oblateness using Qxz were compared. RESULTS: Fifty-two subjects (67.8 ± 5.6 years old) with spherical equivalent refraction from +0.50 to -5.38 were included. The mean paired difference between MRI and original OCT posterior eye Rc was 24.03 ± 46.49 mm (P = 0.0005). For corrected OCT images, the difference in Rc decreased to -0.23 ± 2.47 mm (P = 0.51). The difference between MRI and OCT asphericity, Qxz, was -0.052 ± 0.343 (P = 0.28). However, categorical agreement was only moderate (κ = 0.50). CONCLUSIONS: Distortion-corrected OCT measurements of Rc and Qxz were not statistically significantly different from MRI, although the moderate categorical agreement suggests that individual differences remained. This study provides evidence that with distortion correction, noninvasive office-based OCT could potentially be used instead of MRI for the study of posterior eye shape.


Assuntos
Imageamento por Ressonância Magnética/métodos , Miopia/diagnóstico , Segmento Posterior do Olho/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biometria , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Miopia/epidemiologia , Miopia/fisiopatologia , Retina/patologia , Singapura/epidemiologia
4.
J Biol Chem ; 288(5): 3571-84, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23233667

RESUMO

Autophagy has been shown to facilitate replication or production of avian reovirus (ARV); nevertheless, how ARV induces autophagy remains largely unknown. Here, we demonstrate that the nonstructural protein p17 of ARV functions as an activator of autophagy. ARV-infected or p17-transfected cells present a fast and strong induction of autophagy, resulting in an increased level of autophagic proteins Beclin 1 and LC3-II. Although autophagy was suppressed by 3-methyladenine or shRNAs targeting autophagic proteins (Beclin 1, ATG7, and LC3) as well as by overexpression of Bcl-2, viral transcription, σC protein synthesis, and virus yield were all significantly reduced, suggesting a key role of autophagosomes in supporting ARV replication. Furthermore, we revealed for the first time that p17 positively regulates phosphatase and tensin deleted on chromosome 10 (PTEN), AMP-activated protein kinase (AMPK), and dsRNA dependent protein kinase RNA (PKR)/eIF2α signaling pathways, accompanied by down-regulation of Akt and mammalian target of rapamycin complex 1, thereby triggering autophagy. By using p53, PTEN, PKR, AMPK, and p17 short hairpin RNA (shRNA), activation of signaling pathways and LC3-II levels was significantly suppressed, suggesting that p17 triggers autophagy through activation of p53/PTEN, AMPK, and PKR signaling pathways. Furthermore, colocalization of LC3 with viral proteins (p17 and σC), p62 with LAMP2 and LC3 with Rab7 was observed under a fluorescence microscope. The expression level of p62 was increased at 18 h postinfection and then slightly decreased 24 h postinfection compared with mock infection and thapsigargin treatment. Furthermore, disruption of autophagosome-lysosome fusion by shRNAs targeting LAMP2 or Rab7a resulted in inhibition of viral protein synthesis and virus yield, suggesting that formation of autolysosome benefits virus replication. Taken together, our results suggest that ARV induces formation of autolysosome but does not induce complete autophagic flux.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Orthoreovirus Aviário/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/fisiologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Linhagem Celular , Galinhas , Ativação Enzimática , Fator de Iniciação 2 em Eucariotos/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Biológicos , Orthoreovirus Aviário/crescimento & desenvolvimento , Orthoreovirus Aviário/fisiologia , PTEN Fosfo-Hidrolase/genética , Fagossomos/metabolismo , RNA de Cadeia Dupla/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/metabolismo , eIF-2 Quinase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
J Virol ; 86(24): 13653-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23055561

RESUMO

The specific cell pathways involved in bovine ephemeral fever virus (BEFV) cell entry have not been determined. In this work, colocalization of the M protein of BEFV with clathrin or dynamin 2 was observed under a fluorescence microscope. To better understand BEFV entry, we carried out internalization studies with a fluorescently labeled BEFV by using a lipophilic dye, 3,30-dilinoleyloxacarbocyanine perchlorate (DiO), further suggesting that BEFV uses a clathrin-mediated endocytosis pathway. Our results suggest that clathrin-mediated and dynamin 2-dependent endocytosis is an important avenue of BEFV entry. Suppression of Rab5 or Rab7a through the use of a Rab5 dominant negative mutant and Rab7a short hairpin RNA (shRNA) demonstrated that BEFV requires both early and late endosomes for endocytosis and subsequent infection in MDBK and Vero cells. Treatment of BEFV-infected cells with nocodazole significantly decreased the M protein synthesis and viral yield, indicating that microtubules play an important role in BEFV productive infection, likely by mediating trafficking of BEFV-containing endosomes. Furthermore, BEFV infection was strongly blocked by different inhibitors of endosomal acidification, suggesting that virus enters host cells by clathrin-mediated and dynamin 2-dependent endocytosis in a pH-dependent manner.


Assuntos
Clatrina/fisiologia , Dinamina II/fisiologia , Endocitose/fisiologia , Vírus da Febre Efêmera Bovina/fisiologia , Microtúbulos/fisiologia , Proteínas rab de Ligação ao GTP/fisiologia , Proteínas rab5 de Ligação ao GTP/fisiologia , Animais , Sequência de Bases , Bovinos , Linhagem Celular , Primers do DNA , proteínas de unión al GTP Rab7
6.
Ophthalmology ; 115(10): 1742-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18538409

RESUMO

OBJECTIVE: To describe the relationship of systemic inflammatory disease, complement factor H (CFH) Y402H (1277T-->C) genotype status and age-related macular degeneration (AMD) prevalence in a multiethnic population of whites, blacks, Hispanics, and Chinese. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: We included 5887 persons aged 45 to 84 years with gradable AMD. METHODS: Digital fundus photographs were used to measure AMD. Two years earlier, biomarkers of inflammation were measured and history of inflammatory disease and use of antiinflammatory agents obtained. MAIN OUTCOME MEASURE: Prevalence of AMD. RESULTS: While controlling for age, gender, race/ethnicity, and study site, there were no associations between systemic inflammatory factors and AMD severity. Higher levels of high-sensitivity C-reactive protein (odds ratio [OR] per standard deviation [SD] increase in natural log [ln] units, 2.34; 95% confidence interval [CI], 1.33-4.13) and interleukin-6 (OR per SD in ln, 2.06; 95% CI, 1.21-3.49) were associated with geographic atrophy but not other AMD end points. History of periodontal disease (OR, 1.68; 95% CI, 1.14-2.47) was related to increased retinal pigment. A history of arthritis was associated with soft distinct drusen (OR, 1.24; 95% CI, 1.06-1.46). A history of oral steroid use was related to large drusen (OR, 2.13; 95% CI, 1.14-3.97) and soft distinct drusen (OR, 1.76; 95% CI, 1.00-3.10) and history of cyclooxygenase 2 inhibitor use were associated with large drusen (OR, 1.50; 95% CI, 1.10-2.04), soft indistinct drusen (OR, 1.84; 95% CI, 1.09-3.10), and large drusen area (OR, 1.66; 95% CI, 1.02-2.71). Whites, blacks, and Hispanics with CFH Y402H CC variant genotype had the highest frequency of early AMD compared with those with wild TT genotype. The frequency of CFH did explain some of the difference in AMD prevalence between Chinese and Hispanics compared with whites, but did not explain the difference in prevalence between whites and blacks. CONCLUSIONS: This study confirmed associations of the Y402H CFH gene variant with AMD in nonwhite populations, but neither explained the lack of association between inflammatory factors and AMD in the cohort nor the basis for the observed differences in AMD prevalence across ethnic groups.


Assuntos
Proteína C-Reativa/análise , Etnicidade , Interleucina-6/sangue , Degeneração Macular/genética , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Aterosclerose/sangue , Aterosclerose/genética , Biomarcadores/sangue , Fator H do Complemento/genética , Estudos Transversais , Feminino , Genótipo , Humanos , Inflamação/sangue , Inflamação/tratamento farmacológico , Degeneração Macular/sangue , Degeneração Macular/etnologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Estados Unidos/epidemiologia
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