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1.
J Hum Nutr Diet ; 32(5): 607-618, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31134707

RESUMEN

BACKGROUND: The present study aimed to assess perceived effectiveness and easiness of behavioural diet and lifestyle changes related to dyslipidaemia given by physicians or dieticians as a result of diet and lifestyle modifications being difficult to maintain. METHODS: One-hundred hypercholesterolaemic individuals were enrolled in a parallel, randomised 6-week study. Fifty were advised by dietitians (dietitian group: DG) in six weekly face-to-face behavioural therapy sessions and 50 received standard advice from physicians (physician group: PG). All individuals were followed-up for another 6 weeks under real-life conditions. Questionnaires regarding perceived effectiveness, easiness of adhering, forecasted and actual adherence to specific cholesterol-lowering advice were completed. RESULTS: Scores of perceived effectiveness of advice for sufficient exercise, limiting saturated fat (SFA) intake, eating fish twice a week, consuming plenty of fresh fruit and vegetables, and limiting salt intake different scientifically (all P < 0.05) in PG and DG between study phases. Scores of the individuals' perception of effectiveness at all study phases were higher in the DG compared to PG for sufficient exercise, limiting SFA intake, eating fish twice a week, eating plenty of fruits and vegetables, and limiting salt intake, whereas scores of easiness were significant only for fish consumption (P = 0.008) and using foods with added plant sterols (all P < 0.05). DG and PG significantly differed in forecasted (week 6) versus actual adherence (week 12) to various chances, with DG reporting higher adherence. CONCLUSIONS: Lifestyle and dietary changes related to dyslipidaemia can be achieved with continuous education, monitoring and follow-ups by dieticians, as well as potentially other trained healthcare professionals.


Asunto(s)
Terapia Conductista/métodos , Dieta Saludable/psicología , Estilo de Vida Saludable , Hipercolesterolemia/terapia , Cooperación del Paciente/psicología , Conducta Alimentaria/psicología , Femenino , Adhesión a Directriz , Humanos , Hipercolesterolemia/psicología , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Resultado del Tratamiento
2.
J Hum Nutr Diet ; 31(2): 197-208, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28891084

RESUMEN

BACKGROUND: Evidence from healthcare professionals suggest that consumer compliance to healthy diet and lifestyle changes is often poor. The present study investigated the effect of advice provided by a physician or dietitian on consumer adherence to these measures combined with consuming foods with added plant sterols (PS) with the aim of lowering low-density lipoprotein cholesterol (LDL-C). METHODS: One hundred mildly-to-moderately hypercholesterolaemic individuals were enrolled into a parallel, randomised, placebo-controlled study. Dietitians (dietitian group; DG) advised 50 individuals in six weekly face-to-face behavioural therapy sessions, whereas the other 50 received standard advice from physicians (physician group, PG). Both groups consumed foods with added PS (three servings a day) for 6 weeks. Subsequently, all individuals were followed-up for another 6 weeks under real-life conditions. Blood lipids were measured at baseline and weeks 6 and 12 and 3-day diet diaries were taken at weeks 1, 6 and 12. RESULTS: Individuals in the DG significantly improved their dietary habits, physical activity and increased PS intake compared to the PG. After 6 weeks, LDL-C decreased in both groups compared to baseline without any significant differences between groups. At week 12, LDL-C was further significantly improved only in the DG (P = 0.006) compared to week 6. Total cholesterol, LDL-C and triglycerides were significantly lower in the DG compared to the PG at week 12 after adjusting for levels at week 6 (P < 0.001, P < 0.001 and P = 0.009, respectively). CONCLUSIONS: Although structured counselling by dietitians and common standard advice by physicians were equally effective with respect to improving blood cholesterol after 6 weeks, dietitians were more effective in the longer-term (i.e. 6 weeks after the end of the intervention period).


Asunto(s)
Terapia Conductista/métodos , LDL-Colesterol/sangre , Dieta , Dietética/métodos , Ejercicio Físico , Hipercolesterolemia/terapia , Cooperación del Paciente , Adulto , Comportamiento del Consumidor , Consejo , Registros de Dieta , Conducta Alimentaria , Femenino , Conductas Relacionadas con la Salud , Humanos , Hipercolesterolemia/sangre , Estilo de Vida , Masculino , Nutricionistas , Educación del Paciente como Asunto , Médicos , Fitosteroles/administración & dosificación , Triglicéridos/sangre
3.
J Gen Virol ; 97(3): 767-777, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26694770

RESUMEN

Herpes simplex virus type 1 (HSV-1) establishes a latent infection in sensory neurons from which the virus can periodically reactivate. Whilst latency establishment is thought to result from a failure to express immediate-early genes, we have previously shown that subpopulations of the latent neuronal reservoir have undergone lytic promoter activation prior to latency establishment. In the present study, we have investigated the biological properties of such latently infected neuronal subpopulations using Ai6 fluorescent reporter mice. Using this system we have determined that prior ICP0 or TK promoter activation does not correlate with increased latent virus DNA loads within individual cells and that neurons with evidence of historical lytic cycle promoter activity exhibit a comparable frequency of reactivation to that of the general latent cell population. Comparison of viral DNA content within cells harbouring latent HSV-1 genomes and those undergoing the earliest stages of reactivation has revealed that reactivation can initiate from cells harbouring a wide range of HSV-1 genome copies, but that exiting latency is biased towards cells bearing higher latent virus DNA loads.


Asunto(s)
Herpes Simple/virología , Herpesvirus Humano 1/fisiología , Activación Viral , Latencia del Virus , Animales , Femenino , Regulación Viral de la Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Herpesvirus Humano 1/genética , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Neuronas/virología , Regiones Promotoras Genéticas
4.
J Gen Virol ; 94(Pt 11): 2489-2494, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23907392

RESUMEN

Herpes simplex virus type 1 establishes latency within neurons of the trigeminal ganglion. During latency, viral gene expression is largely restricted to the latency-associated transcripts (LATs), which, whilst not essential for any aspect of latency, function to suppress lytic gene expression and enhance the survival of virus-infected neurons. The latent cell population comprises primary-order neurons infected directly from peripheral tissues and cells infected following further virus spread within the ganglion. In order to assess the role of LAT expression on latency establishment within first-order neurons, we infected ROSA26R reporter mice with Cre recombinase-expressing recombinant viruses harbouring deletion of the thymidine kinase lytic gene and/or the core LAT promoter. We found that LAT expression did not impact on latency establishment in viruses unable to replicate in neurons, and under these conditions, it was not required for the survival of neurons between 3 and 31 days post-infection.


Asunto(s)
Herpesvirus Humano 1/genética , Herpesvirus Humano 1/fisiología , MicroARNs/metabolismo , Neuronas/virología , Latencia del Virus/fisiología , Replicación Viral/fisiología , Animales , Línea Celular , Supervivencia Celular , Humanos , Ratones , Ratones Endogámicos BALB C , MicroARNs/genética , Mutación , Neuronas/citología , Timidina Quinasa/genética , Ganglio del Trigémino/virología , Latencia del Virus/genética
5.
J Virol ; 86(16): 8848-58, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22696655

RESUMEN

Herpes simplex virus 1 (HSV-1) can establish life-long latent infection in sensory neurons, from which periodic reactivation can occur. During latency, viral gene expression is largely restricted to the latency-associated transcripts (LATs). While not essential for any phase of latency, to date the LATs have been shown to increase the efficiency of both establishment and reactivation of latency in small-animal models. We sought to investigate the role of LAT expression in the frequency of latency establishment within the ROSA26R reporter mouse model utilizing Cre recombinase-encoding recombinant viruses harboring deletions of the core LAT promoter (LAP) region. HSV-1 LAT expression was observed to influence the number of latently infected neurons in trigeminal but not dorsal root ganglia. Furthermore, the relative frequencies of latency establishment of LAT-positive and LAT-negative viruses are influenced by the inoculum dose following infection of the mouse whisker pads. Finally, analysis of the infected cell population at two latent time points revealed a relative loss of latently infected cells in the absence of LAT expression. We conclude that the HSV-1 LATs facilitate the long-term stability of the latent cell population within the infected host and that interpretation of LAT establishment phenotypes is influenced by infection methodology.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 1/fisiología , Transcripción Genética , Latencia del Virus , Animales , Línea Celular , Cricetinae , Femenino , Ganglios/virología , Herpesvirus Humano 1/patogenicidad , Ratones
6.
J Exp Med ; 194(3): 301-12, 2001 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-11489949

RESUMEN

Herpesviruses encode a variety of proteins with the potential to disrupt chemokine signaling, and hence immune organization. However, little is known of how these might function in vivo. The B cell-tropic murine gammaherpesvirus-68 (MHV-68) is related to the Kaposi's sarcoma-associated herpesvirus (KSHV), but whereas KSHV expresses small chemokine homologues, MHV-68 encodes a broad spectrum chemokine binding protein (M3). Here we have analyzed the effect on viral pathogenesis of a targeted disruption of the M3 gene. After intranasal infection, an M3 deficiency had surprisingly little effect on lytic cycle replication in the respiratory tract or the initial spread of virus to lymphoid tissues. However, the amplification of latently infected B cells in the spleen that normally drives MHV-68-induced infectious mononucleosis failed to occur. Thus, there was a marked reduction in latent virus recoverable by in vitro reactivation, latency-associated viral tRNA transcripts detectable by in situ hybridization, total viral DNA load, and virus-driven B cell activation. In vivo CD8(+) T cell depletion largely reversed this deficiency, suggesting that the chemokine neutralization afforded by M3 may function to block effective CD8(+) T cell recruitment into lymphoid tissue during the expansion of latently infected B cell numbers. In the absence of M3, MHV-68 was unable to establish a normal latent load.


Asunto(s)
Gammaherpesvirinae/fisiología , Gammaherpesvirinae/patogenicidad , Proteínas Virales/fisiología , Animales , Linfocitos B/inmunología , Linfocitos B/virología , Secuencia de Bases , Linfocitos T CD8-positivos/inmunología , Cartilla de ADN/genética , Femenino , Gammaherpesvirinae/genética , Marcación de Gen , Infecciones por Herpesviridae/etiología , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/virología , Hibridación in Situ , Ratones , Ratones Endogámicos BALB C , Mutación , ARN de Transferencia/análisis , ARN de Transferencia/genética , ARN Viral/análisis , ARN Viral/genética , Bazo/inmunología , Bazo/virología , Proteínas Virales/genética , Replicación Viral
7.
J Exp Med ; 191(3): 573-8, 2000 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-10662803

RESUMEN

Chemokines are a family of small proteins that interact with seven-transmembrane domain receptors and modulate the migration of immune cells into sites of inflammation and infection. The murine gammaherpesvirus 68 M3 gene encodes a secreted 44-kD protein with no sequence similarity to known chemokine receptors. We show that M3 binds a broad range of chemokines, including CC, CXC, C, and CX(3)C chemokines, but does not bind human B cell-specific nor mouse neutrophil-specific CXC chemokines. This herpesvirus chemokine binding protein (hvCKBP) blocks the interaction of chemokines with high-affinity cellular receptors and inhibits chemokine-induced elevation of intracellular calcium levels. hvCKBP is the first soluble chemokine receptor identified in herpesviruses; it represents a novel protein structure with the ability to bind all subfamilies of chemokines in solution and has potential therapeutic applications.


Asunto(s)
Gammaherpesvirinae/genética , Receptores de Quimiocina/genética , Proteínas Virales/genética , Animales , Unión Competitiva , Línea Celular , Quimiocina CCL4 , Quimiocinas/farmacología , Cricetinae , Heparina , Heparitina Sulfato , Humanos , Interleucina-8/metabolismo , Radioisótopos de Yodo , Proteínas Inflamatorias de Macrófagos/metabolismo , Ratones , Sistemas de Lectura Abierta , Unión Proteica/efectos de los fármacos , Receptores de Quimiocina/metabolismo , Proteínas Virales/metabolismo
8.
J Gen Virol ; 90(Pt 10): 2317-2330, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19605591

RESUMEN

Many acute viral infections can be controlled by vaccination; however, vaccinating against persistent infections remains problematic. Herpesviruses are a classic example. Here, we discuss their immune control, particularly that of gamma-herpesviruses, relating the animal model provided by murid herpesvirus-4 (MuHV-4) to human infections. The following points emerge: (i) CD8(+) T-cell evasion by herpesviruses confers a prominent role in host defence on CD4(+) T cells. CD4(+) T cells inhibit MuHV-4 lytic gene expression via gamma-interferon (IFN-gamma). By reducing the lytic secretion of immune evasion proteins, they may also help CD8(+) T cells to control virus-driven lymphoproliferation in mixed lytic/latent lesions. Similarly, CD4(+) T cells specific for Epstein-Barr virus lytic antigens could improve the impact of adoptively transferred, latent antigen-specific CD8(+) T cells. (ii) In general, viral immune evasion necessitates multiple host effectors for optimal control. Thus, subunit vaccines, which tend to prime single effectors, have proved less successful than attenuated virus mutants, which prime multiple effectors. Latency-deficient mutants could make safe and effective gamma-herpesvirus vaccines. (iii) The antibody response to MuHV-4 infection helps to prevent disease but is suboptimal for neutralization. Vaccinating virus carriers with virion fusion complex components improves their neutralization titres. Reducing the infectivity of herpesvirus carriers in this way could be a useful adjunct to vaccinating naive individuals with attenuated mutants.


Asunto(s)
Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/virología , Rhadinovirus/inmunología , Infecciones Tumorales por Virus/inmunología , Infecciones Tumorales por Virus/virología , Animales , Ratones , Linfocitos T/fisiología
9.
Acta Chir Belg ; 109(5): 606-11, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19994803

RESUMEN

AIM: The variability of prognosis of gastric cancer (GC) within a pathological stage necessitates the identification of subgroups of patients with a more aggressive disease. The role of p53 and Ki67 expression in gastric carcinoma is far from being fully established. The aim of the present study was to evaluate the expression of p53 and Ki67 in gastric cancer and correlate the findings with several clinicopathological features and prognosis. MATERIALS AND METHODS: Tissue samples from 93 patients treated by gastric resection for gastric carcinoma between 1996 and 2001 were used. Formalin-fixed paraffin-embedded tumors were studied by immunohistochemistry, using monoclonal antibodies to p53 and Ki67. The results were correlated with clinicopathological features and survival. RESULTS: Stronger expression of p53 was related with tumor size greater than 5 cm and advanced stage. Stronger expression of Ki67 correlated with higher ratio of the number of metastatic lymph nodes to the total number of dissected lymph nodes (metastatic lymph node [MLN] ratio) and advanced stage. Moreover, p53 and Ki67 overexpression, tumor size greater than 5 cm, MLN ratio, depth of invasion, lymph node metastasis, stage III and IV and infiltrative macroscopic appearance were adverse prognostic factors. The levels of p53 and Ki67, the MLN ratio, the tumor size (above 5 cm) and the stage of the disease were identified as independent prognostic factors of survival. CONCLUSIONS: In gastric cancer, the expression of p53 and Ki67 provides significant information about prognosis. The routine evaluation of p53 and Ki67 levels could be a useful tool in identification of patient with more aggressive disease and contribute to a better therapeutic approach.


Asunto(s)
Antígeno Ki-67/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidad , Proteína p53 Supresora de Tumor/metabolismo , Anciano , Proliferación Celular , Femenino , Grecia , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico
10.
Trends Microbiol ; 6(7): 276-82, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9717216

RESUMEN

Murine gammaherpesvirus 68 (MHV-68) is a naturally occurring herpesvirus of wild rodents and is genetically related to human herpesvirus 8 and Epstein-Barr virus. The ability of MHV-68 to establish acute and persistent infection within laboratory mice offers a unique opportunity to investigate immunological and virological aspects of gammaherpesvirus pathogenesis.


Asunto(s)
Gammaherpesvirinae , Infecciones por Herpesviridae , Animales , Modelos Animales de Enfermedad , Ratones
11.
Virus Res ; 111(2): 108-19, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15951043

RESUMEN

The survival strategy of herpes simplex virus centres on the establishment of latency in sensory neurons innervating the site of primary infection followed by periodic reactivation to facilitate transmission. This is a highly evolved and efficient survival mechanism, which despite being the subject of intense research, has proven remarkably difficult to dissect at a molecular level. This review will focus on data, emerging from both in vitro and in vivo model systems, which provide a framework for a mechanistic understanding of latency and the existence and possible significance of non-uniform latent states.


Asunto(s)
Regulación Viral de la Expresión Génica , Simplexvirus/patogenicidad , Latencia del Virus/genética , Animales , Herpes Simple/virología , Histonas/metabolismo , Humanos , Ratones , Neuronas/virología , Simplexvirus/genética , Simplexvirus/fisiología , Activación Viral
12.
Curr Opin Mol Ther ; 1(5): 622-32, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11249669

RESUMEN

In developing any viral gene delivery vector there are two fundamental problems which need to be addressed. Firstly, replication disabled vectors which will be safe for clinical use must be constructed, and secondly, strategies for obtaining appropriate transgene expression in vector transduced cells must be devised. In this review, the progress which has been made in developing herpes simplex virus (HSV)-based gene delivery vectors is discussed, as are the experimental results which have been obtained using these vectors for gene delivery in tissue culture cells and animal models.


Asunto(s)
Técnicas de Transferencia de Gen , Vectores Genéticos , Simplexvirus/genética , Animales , Virus Defectuosos/genética , Expresión Génica , Genes Virales , Terapia Genética/efectos adversos , Terapia Genética/métodos , Humanos , Neoplasias/terapia , Regiones Promotoras Genéticas , Recombinación Genética , Seguridad , Simplexvirus/patogenicidad , Simplexvirus/fisiología , Virulencia/genética , Replicación Viral
13.
J Hum Hypertens ; 16(10): 729-35, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12420198

RESUMEN

This study investigated the differences in the effect of an angiotensin converting enzyme inhibitor (ACEI) compared with an angiotensin receptor blocker (ARB) on blood pressure (BP) and pulse pressure (PP) measured in the clinic (CBP and CPP, respectively), at home (HBP, HPP) and with ambulatory monitoring (ABP, APP). Twenty-seven hypertensive patients were randomised to receive lisinopril (20 mg) or losartan (50 mg) for 5 weeks, and were subsequently crossed-over to the alternative treatment for a second 5-week period. Measurements of CBP, 24-h ABP and 5-days HBP were performed before randomisation and at the end of each treatment period. All measurement methods showed that lisinopril was more effective than losartan in reducing BP. However, the difference between the two drugs was demonstrated with greater precision using HBP (P<0.001) than 24-h ABP (P<0.01), whereas the poorest precision for demonstrating this difference was provided by CBP (P<0.05). Lisinopril was also found more effective than losartan in reducing HPP (P=0.01) and 24-h APP (P=0.03) whereas no such a difference was detected using measurements of CPP. It was concluded that the antihypertensive drugs may differ in their effects not only on BP, but also on PP. HBP monitoring appears to be as reliable as 24-h ABP monitoring in detecting differences in the effect of drugs on both BP and PP. Clinic measurements seem to be the least reliable method, particularly in the detection of differences in PP.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antihipertensivos/uso terapéutico , Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Lisinopril/uso terapéutico , Losartán/uso terapéutico , Pulso Arterial , Monitoreo Ambulatorio de la Presión Arterial , Estudios Cruzados , Femenino , Servicios de Atención de Salud a Domicilio , Humanos , Masculino , Visita a Consultorio Médico , Reproducibilidad de los Resultados , Resultado del Tratamiento
14.
Dig Liver Dis ; 36(1): 13-20, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14971811

RESUMEN

BACKGROUND AND AIMS: To provide a direct comparison of Helicobacter pylori-positive subjects bleeding from duodenal ulcer with H. pylori-negative ones, in terms of severity of bleeding and outcome. PATIENTS AND METHODS: A case-control study was prospectively conducted in 105 H. pylori-negative duodenal ulcer bleeders and same number of sex- and age-matched H. pylori-positive ones. RESULTS: NSAID consumption was more common among H. pylori-negative subjects (81%) compared to their H. pylori-positive counterparts (58.1%, P < 0.001). H. pylori-negative bleeders were found to need more often haemostasis (55.2% versus 31.4%, P < 0.001) or surgical intervention (15.2% versus 4.8%, P = 0.011) and to have a greater proportion of rebleeding (32.4% versus 13.3%, P = 0.001), a more prolonged hospitalisation (11.6 +/- 4.1 versus 6.2 +/- 1.5 days, P < 0.001) and a higher rate of in-hospital mortality (15.2% versus 3.8%, P = 0.005). In the overall population (N = 210), H. pylori negativity, among other known risk factors, emerged as independent predictor (odds ratio: 3.2; 95% CI: 1.5, 11.2; P = 0.004) of an unfavourable outcome (surgery or death). CONCLUSIONS: Duodenal ulcer bleeding in H. pylori-negative subjects appears to be more severe, to have a higher rate of rebleeding, and to lead more often to surgery or fatality compared to the vast majority of H. pylori-positive duodenal ulcer bleeders.


Asunto(s)
Úlcera Duodenal/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/aislamiento & purificación , Úlcera Péptica Hemorrágica/etiología , Anciano , Estudios de Casos y Controles , Úlcera Duodenal/complicaciones , Úlcera Duodenal/diagnóstico , Endoscopía Gastrointestinal , Femenino , Infecciones por Helicobacter/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/microbiología , Estudios Prospectivos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
15.
Methods Mol Med ; 10: 345-54, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-21374240

RESUMEN

Assays in use for the analysis of herpes simplex virus (HSV) gene expression during the establishment and maintenance phases of infection in the nervous system include: 1 The use of reporter genes, for example, the lacZ gene from Escherichia coli, which is inserted by homologous recombination into the viral genome, and which may be driven either by viral promoters or by an exogenous promoter, such as the major immediate early (IE) promoter of cytomegalovirus. In our hands, the detection of lacZ activity in neuronal tissue infected with recombinant HSV constructs has proven to be a simple and effective means of monitoring viral activity in the peripheral nervous system. 2. Analysis of virally encoded RNA transcripts, either by in situ hybridization (ISH) using radioactive or nonradioactive indicator molecules, or by Northern analysis (this technique is described in Chapters 13 and 24 ). 3. Immunohistochemistry to demonstrate the presence of viral proteins, which technique can also be used in combination with ISH (dual labeling).

16.
Science ; 337(6091): 199-204, 2012 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-22745253

RESUMEN

Influenza A virus (IAV) infection leads to variable and imperfectly understood pathogenicity. We report that segment 3 of the virus contains a second open reading frame ("X-ORF"), accessed via ribosomal frameshifting. The frameshift product, termed PA-X, comprises the endonuclease domain of the viral PA protein with a C-terminal domain encoded by the X-ORF and functions to repress cellular gene expression. PA-X also modulates IAV virulence in a mouse infection model, acting to decrease pathogenicity. Loss of PA-X expression leads to changes in the kinetics of the global host response, which notably includes increases in inflammatory, apoptotic, and T lymphocyte-signaling pathways. Thus, we have identified a previously unknown IAV protein that modulates the host response to infection, a finding with important implications for understanding IAV pathogenesis.


Asunto(s)
Sistema de Lectura Ribosómico , Subtipo H1N1 del Virus de la Influenza A/genética , Virus de la Influenza A/genética , Sistemas de Lectura Abierta , Infecciones por Orthomyxoviridae/virología , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Codón , Secuencia Conservada , Femenino , Regulación de la Expresión Génica , Genoma Viral , Células HEK293 , Humanos , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Virus de la Influenza A/metabolismo , Pulmón/patología , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Mutación , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/patología , Dominios y Motivos de Interacción de Proteínas , Proteoma , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/genética , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/química , Virus Reordenados/genética , Proteínas Represoras/química , Proteínas no Estructurales Virales/química , Proteínas Virales/biosíntesis , Proteínas Virales/química , Replicación Viral
20.
J Gen Virol ; 74 ( Pt 7): 1363-70, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8393077

RESUMEN

During latent infection of neurons with herpes simplex virus type 1 (HSV-1), several RNA transcripts of varying abundance arise from a single locus within the virus repeats. The functions of latency-associated transcripts (LATs) are unknown and the relationship between the various RNA species requires further clarification. Reported here is a novel approach to the study of HSV transcripts during latency, based on the increasing realization that cellular and viral RNAs are synthesized and processed by macromolecular complexes that occupy discrete compartments within the nucleoplasm of a cell. High resolution non-isotopic in situ hybridization was used to study the intranuclear topology of HSV-1 LATs in primary sensory neurons of latently infected mice and humans. Low abundance (minor) LATs were localized to sharply defined intranuclear foci of 1 to 3 microns in diameter. On average, there were 2.6 to 2.8 foci/LAT+ neuronal profile (5 microns), representing 13 to 14 foci/cell. In contrast to the focal deployment of minor LATs, the more abundant latency-associated RNAs were distributed diffusely throughout the nucleoplasms of latency infected neurons, with prominent sparing of nucleolar regions. These data establish a foundation for studying the synthesis, processing and transport of LATs in vivo. It should now be possible to investigate the nature of those cellular products which associate with HSV-1 encoded LATs in vivo and thereby determine whether minor LATs are associated with previously characterized macromolecular complexes, such as those responsible for processing of pre-messenger RNA.


Asunto(s)
Núcleo Celular/microbiología , Ganglios Espinales/microbiología , Herpes Simple/fisiopatología , Neuronas/microbiología , ARN Viral/análisis , Simplexvirus/aislamiento & purificación , Ganglio del Trigémino/microbiología , Animales , Núcleo Celular/ultraestructura , Femenino , Humanos , Hibridación in Situ , Ratones , Ratones Endogámicos BALB C , ARN Viral/biosíntesis , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Simplexvirus/genética , Simplexvirus/ultraestructura , Transcripción Genética , Células Vero
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