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1.
J Virol ; 89(17): 8773-82, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26063427

RESUMO

UNLABELLED: Through its interaction with the 5' translation initiation factor eIF4G, poly(A) binding protein (PABP) facilitates the translation of 5'-capped and 3'-poly(A)-tailed mRNAs. Rotavirus mRNAs are capped but not polyadenylated, instead terminating in a 3' GACC motif that is recognized by the viral protein NSP3, which competes with PABP for eIF4G binding. Upon rotavirus infection, viral, GACC-tailed mRNAs are efficiently translated, while host poly(A)-tailed mRNA translation is, in contrast, severely impaired. To explore the roles of NSP3 in these two opposing events, the translational capabilities of three capped mRNAs, distinguished by either a GACC, a poly(A), or a non-GACC and nonpoly(A) 3' end, have been monitored after electroporation of cells expressing all rotavirus proteins (infected cells) or only NSP3 (stably or transiently transfected cells). In infected cells, we found that the magnitudes of translation induction (GACC-tailed mRNA) and translation reduction [poly(A)-tailed mRNA] both depended on the rotavirus strain used but that translation reduction not genetically linked to NSP3. In transfected cells, even a small amount of NSP3 was sufficient to dramatically enhance GACC-tailed mRNA translation and, surprisingly, to slightly favor the translation of both poly(A)- and nonpoly(A)-tailed mRNAs, likely by stabilizing the eIF4E-eIF4G interaction. These data suggest that NSP3 is a translational surrogate of the PABP-poly(A) complex; therefore, it cannot by itself be responsible for inhibiting the translation of host poly(A)-tailed mRNAs upon rotavirus infection. IMPORTANCE: To control host cell physiology and to circumvent innate immunity, many viruses have evolved powerful mechanisms aimed at inhibiting host mRNA translation while stimulating translation of their own mRNAs. How rotavirus tackles this challenge is still a matter of debate. Using rotavirus-infected cells, we show that the magnitude of cellular poly(A) mRNA translation differs with respect to rotavirus strains but is not genetically linked to NSP3. Using cells expressing rotavirus NSP3, we show that NSP3 alone not only dramatically enhances rotavirus-like mRNA translation but also enhances poly(A) mRNA translation rather than inhibiting it, likely by stabilizing the eIF4E-eIF4G complex. Thus, the inhibition of cellular polyadenylated mRNA translation during rotavirus infection cannot be attributed solely to NSP3 and is more likely the result of global competition between viral and host mRNAs for the cellular translation machinery.


Assuntos
Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Proteínas de Ligação a Poli(A)/metabolismo , Biossíntese de Proteínas/fisiologia , Proteínas não Estruturais Virais/metabolismo , Animais , Linhagem Celular , Cricetinae , Eletroporação , Células HeLa , Humanos , Macaca mulatta , Poli A/genética , Poliadenilação/genética , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Viral/genética , Rotavirus/genética , Infecções por Rotavirus/virologia , Transfecção
2.
J Vasc Surg ; 63(5): 1371-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27109797

RESUMO

We present three patients with dissecting and saccular aneurysms affecting the cervical carotid and vertebral arteries treated with flow diversion using the Pipeline Embolization Device (ev3 Endovascular Inc/Covidien, Plymouth, Minn). The device was successfully deployed in all three patients without complication. Follow-up imaging studies at 8 to 18 months revealed complete occlusion of all three aneurysms. This device may be a valuable alternative to stent-graft devices in the treatment of cervical aneurysms since it is delivered through a microcatheter that is better able to negotiate tortuous anatomy of cervical carotid and vertebral arteries.


Assuntos
Dissecção Aórtica/terapia , Doenças das Artérias Carótidas/terapia , Embolização Terapêutica/instrumentação , Dispositivos de Acesso Vascular , Dissecação da Artéria Vertebral/terapia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Angiografia Digital , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/fisiopatologia , Angiografia Cerebral/métodos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Resultado do Tratamento , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/fisiopatologia
3.
J Med Virol ; 87(8): 1389-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25908062

RESUMO

Better understanding of the correlation between high-risk HPV DNA testing, viral load quantitation, and E6/E7 mRNA detection is required. The aim of this study was to assess the relationship between these markers and the severity of cervical lesions. One-hundred and fifty one directed cervical specimens were analysed (normal, cervical intraepithelial neoplasia, and cancer). HPV types 16, 18, 31, 33, and 45 DNA detection and quantititation and E6/E7 mRNA detection were performed. DNA was detected in 87 (57.6%) samples and increased from 0% (normal) to 93.9% (cancer). E6/E7 mRNA was detected in 65 (43%) samples and increased with the severity of the lesions from 0% (normal) to 78.8% (26/33) (cancers) (P < 0.001). HPV DNA and E6/E7 mRNA detection were compared in the 141 samples harbouring HPV16, 18, 31, 33, or 45 infection: 45.4% (64/141) of specimens were DNA-/mRNA-, 46% (65/141) were DNA + /mRNA+ and 8.5% (12/141) were DNA + /mRNA-. The proportion of DNA + /mRNA+ specimens increased with the severity of the lesions (P < 0.001). All normal cervix specimens were DNA-/mRNA-. Among grade 2 cervical intraepithelial neoplasia, prevalence of DNA was higher than that of mRNA: 41.6% (5/12) versus 25% (3/12), whereas it was 79.3% (46/58) versus 62% (36/58) among grade 3 cervical intraepithelial neoplasia. Full concordance was observed in cancers as all the 26 DNA+ specimens were mRNA +. Median overall HPV load was higher in DNA + /mRNA+ than in DNA + /mRNA- specimens (1.41 × 10(6) vs. 9.1 × 10(2) copies per million cells, P < 0.001). Both E6/E7 mRNA detection and concordant DNA + /mRNA+ detection increases with the severity of the lesions and with the HPV DNA load.


Assuntos
Proteínas Oncogênicas Virais/biossíntese , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , RNA Mensageiro/análise , Índice de Gravidade de Doença , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Estudos Transversais , Feminino , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , RNA Mensageiro/genética , RNA Viral/análise , RNA Viral/genética , Neoplasias do Colo do Útero/virologia
4.
J Virol ; 82(22): 11283-93, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18799579

RESUMO

Rotavirus nonstructural protein NSP3 interacts specifically with the 3' end of viral mRNAs, with the eukaryotic translation initiation factor eIF4G, and with RoXaN, a cellular protein of yet-unknown function. By evicting cytoplasmic poly(A) binding protein (PABP-C1) from translation initiation complexes, NSP3 shuts off the translation of cellular polyadenylated mRNAs. We show here that PABP-C1 evicted from eIF4G by NSP3 accumulates in the nucleus of rotavirus-infected cells. Through modeling of the NSP3-RoXaN complex, we have identified mutations in NSP3 predicted to interrupt its interaction with RoXaN without disturbing the NSP3 interaction with eIF4G. Using these NSP3 mutants and a deletion mutant unable to associate with eIF4G, we show that the nuclear localization of PABP-C1 not only is dependent on the capacity of NSP3 to interact with eIF4G but also requires the interaction of NSP3 with a specific region in RoXaN, the leucine- and aspartic acid-rich (LD) domain. Furthermore, we show that the RoXaN LD domain functions as a nuclear export signal and that RoXaN tethers PABP-C1 with RNA. This work identifies RoXaN as a cellular partner of NSP3 involved in the nucleocytoplasmic localization of PABP-C1.


Assuntos
Fator de Iniciação Eucariótico 4G/metabolismo , Proteínas de Ligação a Poli(A)/metabolismo , Mapeamento de Interação de Proteínas , Proteínas de Ligação a RNA/metabolismo , Rotavirus/fisiologia , Proteínas não Estruturais Virais/metabolismo , Substituição de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Haplorrinos , Humanos , Mutagênese Sítio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Deleção de Sequência
5.
Artigo em Inglês | MEDLINE | ID: mdl-22540286

RESUMO

Colour additives are dyes, pigments or other substances that can impart colour when added or applied to food, drugs, cosmetics, medical devices, or the human body. The substances must be pre-approved by the US Food and Drug Administration (USFDA) and listed in Title 21 of the US Code of Federal Regulations before they may be used in products marketed in the United States. Some also are required to be batch certified by the USFDA prior to their use. Both domestic and imported products sold in interstate commerce fall under USFDA jurisdiction, and the USFDA's district laboratories use a combination of analytical methods for identifying or confirming the presence of potentially violative colour additives. We have developed a qualitative method for identifying 17 certifiable, certification exempt, and non-permitted colour additives in various food products. The method involves extracting the colour additives from a product and isolating them from non-coloured components with a C(18) Sep-Pak cartridge. The colour additives are then separated and identified by liquid chromatography (LC) with photodiode array detection, using an Xterra RP18 column and gradient elution with aqueous ammonium acetate and methanol. Limits of detection (LODs) ranged from 0.02 to 1.49 mg/l. This qualititative LC method supplements the visible spectrophotometric and thin-layer chromatography methods currently used by the USFDA's district laboratories and is less time-consuming and requires less solvent compared to the other methods. The extraction step in the new LC method is a simple and an efficient process that can be used for most food types.


Assuntos
Corantes de Alimentos/análise , Cromatografia Líquida de Alta Pressão , Corantes de Alimentos/normas , Limite de Detecção , Estados Unidos , United States Food and Drug Administration
6.
Rev. cienc. salud (Bogotá) ; 6(1): 26-35, abr. 2008. tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-635921

RESUMO

La hipercalciuria idiopática (HI) es un trastorno metabólico frecuente, con curso clínico, la mayoría de las veces asintomático. Sin embargo, en algunos pacientes se manifiesta clínicamente con hematuria, polaquiuria, disuria, incontinencia urinaria, enuresis y dolor abdominal o lumbar, los cuales afectan las actividades diarias de los niños y motivan consultas médicas repetitivas, con los costos que esto genera. Se requiere de la sospecha clínica y el conocimiento de la enfermedad para su diagnóstico y tratamiento oportunos. Objetivo. Determinar los factores relacionados con el desarrollo de la forma sintomática de HI, para lo cual se estudiaron: la magnitud de la calciuria, el antecedente familiar de urolitiasis, el género, la edad y la excreción de oxalato de calcio. El propósito final fue ampliar y difundir el conocimiento de la enfermedad dentro de la comunidad médica. Materiales y métodos. Se realizó un estudio analítico de casos y controles para determinar la relación existente entre los factores mencionados y la presencia de síntomas de HI. La población de estudio estuvo compuesta por 60 pacientes con diagnóstico establecido de HI, de la consulta de Nefropediatría de la Fundación Cardioinfantil, con edades entre los 2 y los 13 años. La metodología consistió en un estudio no pareado con 1,4 casos por cada control. Para el análisis estadístico de las asociaciones entre los factores en estudio y la HI sintomática se utilizó la prueba exacta de Fisher y el Ji cuadrado de Pearson con un nivel de significancia del 5% (p<0,05). Para establecer la fuerza de la asociación se calculó la razón de disparidad (OR) y el intervalo de confianza del 95%. Además, se determinaron las variables que explican en conjunto la HI sintomática, controlando las variables de confusión con un modelo de regresión logística incondicional a un nivel de significancia del 5% (p<0,05). Resultados. Se establecieron asociaciones entre los siguientes factores y la presencia de síntomas de HI en niños: el género masculino (p = 0,006; OR = 6,2; IC = 1,6-24,5) y la magnitud de la calciuria (p = 0,003). Con menor diferencia estadística se encontraron el antecedente familiar positivo de urolitiasis (p = 0,018; OR = 4,889; IC = 1,26-19,48) y el incremento en la edad (p = 0,044). La presencia de oxalato de calcio en el uroanálisis no se relacionó con los síntomas de HI (p = 0,2; OR = 0,59; IC = 0,17-1,49). Conclusiones. Los valores elevados de calciuria (mayor a 6 mg/kg/día) y el género masculino, se asocian con la presencia de síntomas de HI en niños. Adicionalmente, se observaron, con frecuencia, en el grupo de pacientes sintomáticos, la presencia de niños de edades mayores y el antecedente familiar positivo de litiasis renal, aunque no se evidencian diferencias significativas para estos dos factores. El hallazgo de cristales de oxalato de calcio en el uroanálisis no se relacionó con los síntomas de HI.


Idiopathic Hypercalciuria (IH) is a metabolic disease, in most cases asymptomatic, but some patients express complaints consistent with hematuria, polaquiuria, dysuria, urinary incontinence, enuresis and abdominal or back pain, that affects activities of children, can lead to repetitive consult and secundary cost. Is necessary the clinical suspect for oportune diagnosis and treatment. Objective. To determine the factors that hasten the development of symptomatic Hypercalciuria: calciuria magnitude, urolithiasis family history, gender, age and urinary excretion of calcium oxalate. The final purpose is to spread the knowledge of the disease in the medical community. Materials and methods. We studied 60 children between two and thirteen years with IH diagnosis at an outpatient clinic, in a not matched case-control study (1,4: 1 ratio), to determine the relationship between factors and IH symptoms. In stadistical analysis of associations we used the Fisher test and Chi squared of Pearson in significancy level of 5% (p<0.05). For determine the association force we calculed the odds ratios (OR) with 95% confidence intervals (95% CIs). Also, the variables that in conjunct explain symptomatic IH, controling the confussional variables with an inconditional logistic regression analysis, with a significancy level of 5% (p<0.05). Results. We established the associations betwen the folowing factors and symptomatic IH: male gender (p = 0.006; OR = 6.2; IC = 1.6-24.5) and calciuria magnitude (p = 0,003). With low stadistic difference, we found positive family history of urolithiasis (p = 0.018; OR 4.889 (IC = 1.26-19.48) and age increment (p = 0.044). The presence of urine calium oxalate doesn't show relation with IH symptoms (p = 0.2; OR = 0.59; IC = 0.17-1.49). Conclusions. Children with elevated values of calciuria (above 6 mg/kg/day) and male gender, may have a higher risk of symptomatic IH. Urolithiasis familiar history and age increment were frequent in patients with symptoms, without stadistic diferences. The presence of urine calcium oxalate doesn't influence IH symptoms.


Assuntos
Humanos , Pré-Escolar , Criança , Hipercalciúria , Criança , Estudos Retrospectivos , Enurese , Disuria
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