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1.
J Endocrinol Invest ; 43(7): 995-1000, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31970690

RESUMO

PURPOSE: The aim of this study was to determine whether the triglycerides and glucose (TyG) index is associated with the presence of metabolically obese normal-weight (MONW) phenotype and related cardiovascular risk factors. METHODS: Apparently healthy men and non-pregnant women aged 20-65 years were enrolled in a population-based cross-sectional study. Overweight, obesity, smoking, alcohol consumption, pregnancy, diagnosis of hypertension, diabetes, cardiovascular disease, liver disease, renal disease, malignancy, and medical treatment were exclusion criteria. Subjects were allocated into the MONW or normal-weight groups. MONW phenotype was defined by normal weight and the presence of at least one of the following cardiovascular risk factors: elevated blood pressure, hyperglycemia, hypertriglyceridemia, and low HDL cholesterol. RESULTS: A total of 542 subjects were enrolled and allocated into the MONW (n = 354) and normal-weight (n = 188) groups. The adjusted logistic regression analysis showed that the elevated TyG index is significantly associated with the presence of MONW phenotype (OR = 11.14; 95% CI 6.04-20.57), hyperglycemia (OR = 3.18; 95% CI 1.95-5.21), hypertriglyceridemia (OR = 399.19; 95% CI 94.01-1694.98), and low HDL-C (OR = 2.60; 95% CI 1.74-3.87), but not with elevated blood pressure (OR = 1.55; 95% CI 0.93-2.60). CONCLUSION: Results of this study support that the TyG index may be a useful indicator to detect MONW phenotype and associated cardiovascular risk factors.


Assuntos
Glicemia/metabolismo , Fatores de Risco de Doenças Cardíacas , Peso Corporal Ideal , Triglicerídeos/sangue , Adulto , Idoso , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Hiperglicemia/complicações , Hiperglicemia/epidemiologia , Hiperglicemia/metabolismo , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/metabolismo , Hipertrigliceridemia/complicações , Hipertrigliceridemia/epidemiologia , Hipertrigliceridemia/metabolismo , Peso Corporal Ideal/fisiologia , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Fenótipo , Fatores de Risco , Adulto Jovem
2.
Drugs Today (Barc) ; 55(10): 641-652, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31720561

RESUMO

ROS1 gene fusions account for approximately 1-2% of all cases of non-small cell lung cancer (NSCLC). Similarly to anaplastic lymphoma kinase (ALK)-positive NSCLC, patients with ROS1+ NSCLC tend to have minimal smoking and be of the female sex. In most cases, adenocarcinoma is the dominant histology. The ROS1 gene has homology to ALK and this structural similarity formed the basis for utilizing ALK inhibitors for ROS1+ NSCLC. On the basis of impressive progression-free survival of 19.2 months from the PROFILE 1001 trial, crizotinib obtained Food and Drug Administration (FDA) approval as first-line therapy for treatment of ROS1+ NSCLC. Since then, there has been a growing appreciation of the incidence of brain metastases in ROS1+ NSCLC and rates of central nervous system progression on crizotinib. Additionally, appreciation of novel resistance mechanisms to crizotinib has led to the development of newer tyrosine kinase inhibitors (TKIs). In this review, we highlight known and emerging TKIs for the management of ROS1+ NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Terapia de Alvo Molecular , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Humanos , Inibidores de Proteínas Quinases/uso terapêutico
4.
Int Endod J ; 52(4): 424-438, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30244498

RESUMO

AIM: To evaluate the potential biostimulatory effects of grape seed extract (GSE) on a primary culture of human pulp cells. METHODOLOGY: Human molars were used to obtain the primary pulp cell culture and 0.5-mm dentine discs. For GSE direct exposure, dose-response (0.0065-6.5%) and time response (1-60 min of contact) were examined. For transdentinal exposure, 0.65% of GSE was tested for 24 h. Cellular metabolism, nitric oxide and collagen production, and cell morphology alterations were assessed at periods of 24 and 72 h. After cell differentiation and direct exposure to GSE, the total protein production (TP), alkaline phosphatase activity (ALP) and formation of mineralization nodules (MN) were assessed. The results were analysed by parametric tests or non-parametric tests (α = 0.05). RESULTS: The lower concentration of GSE tested (0.0065%) was associated with an increase in cellular metabolism, a reduction in the production of nitric oxide and an increase in extracellular matrix synthesis (collagen). Distinct behaviours were observed for the different concentrations, without a reduction of cellular metabolism >10% compared with the control, either when applied directly or transdentinally. SEM revealed no significant change in cell morphology, except for the positive control (H2 O2 ). There was no difference in TP, ALP or MN between the control group and the group exposed to GSE. CONCLUSIONS: Treatment with grape seed extract, even at the highest concentration and longest period, caused neither direct nor transdentinal cytotoxic effects on human pulp cells. Grape seed extract components may play a biostimulatory role and protect dental pulp cells when in direct contact.


Assuntos
Extrato de Sementes de Uva , Proantocianidinas , Diferenciação Celular , Polpa Dentária , Dentina , Humanos
5.
Opt Express ; 26(2): 1556-1563, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29402029

RESUMO

In this work, the influence of induced losses on the saturable absorption by zinc nanoparticles photodeposited onto the core of an optical fiber end is reported. Samples with different losses were obtained by the photodeposition technique using a continuous wave laser at 1550 nm. The nonlinear absorption of the saturable absorber was characterized by the P-scan technique using a high-gain pulsed erbium-doped fiber amplifier. The results have demonstrated that for optical fibers with variable induced losses by deposited nanoparticles, the modulation depth increases proportionally based on the nonlinear absorption coefficient. With induced losses fixed at 3 dB, it was demonstrated that the modulation depth increased as a function of the optical power used in the photodeposition process. The saturation intensity of the saturable absorber presents small shifts for higher intensities.

6.
Antiviral Res ; 145: 114-122, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28780422

RESUMO

Potency tests for commercial oil-adjuvanted foot-and-mouth disease (FMD) vaccines are usually carried out in cattle, using a full dose (2 ml) of vaccine and homologous virus challenge. However, in sheep the recommended vaccine dose is half of the cattle dose (1 ml) and most vaccines have not been potency tested for this species, especially with heterologous viruses. To determine the efficacy of a high potency (>6PD50) FMD virus (FMDV) O1Manisa vaccine in sheep, we carried out a study using a heterologous FMDV (FMDV O/SKR/2010 - Mya-98 strain) challenge. Groups of seven animals each were vaccinated with 2×, 1×, 1/2× or 1/4× dose (2 ml, 1 ml, 0.5 ml or 0.25 ml respectively) and challenged at 7 days post vaccination (dpv). Only 3 of the 7 sheep in the group vaccinated with 2 ml were protected. With 2 additional groups, receiving double or single doses and challenged at 14 dpv, 4 of 7 sheep were protected in each group. None of the sheep had measurable neutralising antibodies against the vaccine or challenge virus at 7 dpv. However, all vaccinated animals challenged at 14 dpv had a homologous neutralising response against FMDV O1 Manisa on the day of challenge and all but one animal also had a heterologous response to FMDV O/SKR/2010. Infectious FMDV and viral RNA could be found in nasal swabs between 1 and 6 days post challenge (dpc) in most vaccinated sheep, but those vaccinated with higher doses or challenged at 14 dpv showed significant decreases in the level of FMDV detection. Intermittent virus shedding was noticed between 1 and 35 dpc in all vaccinated groups, but persistent infection could be demonstrated only in 4 sheep (20%). This study showed that at the recommended dose, a high potency (>6 PD50) FMDV O1Manisa vaccine does not protect sheep against a heterologous challenge at 7 dpv. However, partial protection was observed when a double dose was used at 7 dpv or when double or single dose vaccinated sheep were challenged at 14 dpv.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Doenças dos Ovinos/prevenção & controle , Potência de Vacina , Vacinas Virais , Adjuvantes Imunológicos , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Relação Dose-Resposta Imunológica , Febre Aftosa/imunologia , Febre Aftosa/virologia , Nariz/virologia , RNA Viral , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/virologia , Vacinação/veterinária , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Eliminação de Partículas Virais
7.
Transbound Emerg Dis ; 64(2): 547-563, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26301461

RESUMO

Foot-and-mouth disease (FMD) is a major constraint to transboundary trade in animal products, yet much of its natural ecology and epidemiology in endemic regions is still poorly understood. To address this gap, a multidisciplinary, molecular and conventional epidemiological approach was applied to an investigation of endemic FMD in Vietnam. Within the study space, it was found that 22.3% of sampled ruminants had previously been infected with FMD virus (FMDV), of which 10.8% were persistent, asymptomatic carriers (2.4% of the total population). Descriptive data collected from targeted surveillance and a farm questionnaire showed a significantly lower prevalence of FMDV infection for dairy farms. In contrast, farms of intermediate size and/or history of infection in 2010 were at increased risk of FMD exposure. At the individual animal level, buffalo had the highest exposure risk (over cattle), and there was spatial heterogeneity in exposure risk at the commune level. Conversely, carrier prevalence was higher for beef cattle, suggesting lower susceptibility of buffalo to persistent FMDV infection. To characterize virus strains currently circulating in Vietnam, partial FMDV genomic (VP1) sequences from carrier animals collected between 2012 and 2013 (N = 27) and from FMDV outbreaks between 2009 and 2013 (N = 79) were compared by phylogenetic analysis. Sequence analysis suggested that within the study period, there were two apparent novel introductions of serotype A viruses and that the dominant lineage of serotype O in Vietnam shifted from SEA/Mya-98 to ME-SA/PanAsia. FMDV strains shared close ancestors with FMDV from other South-East Asian countries indicating substantial transboundary movement of the predominant circulating strains. Close genetic relationships were observed between carrier and outbreak viruses, which may suggest that asymptomatic carriers of FMDV contribute to regional disease persistence. Multiple viral sequences obtained from carrier cattle over a 1-year period had considerable within-animal genetic variation, indicating within-host virus evolution.


Assuntos
Portador Sadio/veterinária , Febre Aftosa/epidemiologia , Animais , Portador Sadio/virologia , Bovinos , Febre Aftosa/transmissão , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/isolamento & purificação , Variação Genética , Filogenia , RNA Viral/genética , Análise de Sequência , Sorotipagem/veterinária , Vietnã/epidemiologia
8.
Transbound Emerg Dis ; 64(2): 564-573, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26303975

RESUMO

Foot-and-mouth disease (FMD) is a highly contagious livestock disease of high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid outbreak control. Air sampling collection has been demonstrated as a useful technique for detection of FMDV RNA in infected animals, related to the aerogenous nature of the virus. In the current study, air from rooms housing individual (n = 17) or two groups (n = 4) of cattle experimentally infected with FDMV A24 Cruzeiro of different virulence levels was sampled to assess the feasibility of applying air sampling as a non-invasive, screening tool to identify sources of FMDV infection. Detection of FMDV RNA in air was compared with first detection of clinical signs and FMDV RNA levels in serum and oral fluid. FMDV RNA was detected in room air samples 1-3 days prior (seven animals) or on the same day (four animals) as the appearance of clinical signs in 11 of 12 individually housed cattle. Only in one case clinical signs preceded detection in air samples by one day. Overall, viral RNA in oral fluid or serum preceded detection in air samples by 1-2 days. Six individually housed animals inoculated with attenuated strains did not show clinical signs, but virus was detected in air in one of these cases 3 days prior to first detection in oral fluid. In groups of four cattle housed together, air detection always preceded appearance of clinical signs by 1-2 days and coincided more often with viral shedding in oral fluid than virus in blood. These data confirm that air sampling is an effective non-invasive screening method for detecting FMDV infection in confined to enclosed spaces (e.g. auction barns, milking parlours). This technology could be a useful tool as part of a surveillance strategy during FMD prevention, control or eradication efforts.


Assuntos
Filtros de Ar , Microbiologia do Ar , Vírus da Febre Aftosa/genética , Febre Aftosa/diagnóstico , RNA Viral/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Surtos de Doenças/prevenção & controle , Diagnóstico Precoce , Manejo de Espécimes/instrumentação , Eliminação de Partículas Virais
9.
J Comp Pathol ; 155(4): 314-325, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27697284

RESUMO

For the purpose of developing an improved experimental model for studies of foot-and-mouth disease virus (FMDV) infection in cattle, three different experimental systems based on natural or simulated natural virus exposure were compared under standardized experimental conditions. Ante-mortem infection dynamics were characterized in cattle exposed to FMDV through a novel, simulated natural intranasopharyngeal (INP) inoculation system or through standardized and controlled systems of within- or between-species direct contact exposure (cattle-to-cattle or pig-to-cattle). All three systems were efficient in causing synchronous, generalized foot-and-mouth disease in cattle exposed to one of three different strains of FMDV representing serotypes O, A and Asia1. There was more within-group variation in the timing of clinical infection following natural and simulated natural virus exposure systems when compared with the conventionally used system of needle inoculation (intraepithelial lingual inoculation). However, the three optimized exposure systems described herein have the advantage of closely simulating field conditions by utilizing natural routes of primary infection, thereby facilitating engagement of mucosal host defence mechanisms. Overall, it is concluded that INP inoculation and standardized systems of direct contact exposure provide effective alternatives to conventional (needle) inoculation systems for studies in which it is desirable to simulate the natural biology of FMDV infection.


Assuntos
Modelos Animais de Doenças , Febre Aftosa/transmissão , Animais , Bovinos , Vírus da Febre Aftosa , Suínos
10.
Transbound Emerg Dis ; 63(2): 152-64, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24943477

RESUMO

A systematic study was performed to investigate the potential of pigs to establish and maintain persistent foot-and-mouth disease virus (FMDV) infection. Infectious virus could not be recovered from sera, oral, nasal or oropharyngeal fluids obtained after resolution of clinical infection with any of five FMDV strains within serotypes A, O and Asia-1. Furthermore, there was no isolation of live virus from tissue samples harvested at 28-100 days post-infection from convalescent pigs recovered from clinical or subclinical FMD. Despite lack of detection of infectious FMDV, there was a high prevalence of FMDV RNA detection in lymph nodes draining lesion sites harvested at 35 days post-infection, with the most frequent detection recorded in popliteal lymph nodes (positive detection in 88% of samples obtained from non-vaccinated pigs). Likewise, at 35 dpi, FMDV capsid antigen was localized within follicles of draining lymph nodes, but without concurrent detection of FMDV non-structural protein. There was a marked decline in the detection of FMDV RNA and antigen in tissue samples by 60 dpi, and no antigen or viral RNA could be detected in samples obtained at 100 dpi. The data presented herein provide the most extensive investigation of FMDV persistence in pigs. The overall conclusion is that domestic pigs are unlikely to be competent long-term carriers of infectious FMDV; however, transient persistence of FMDV protein and RNA in lymphoid tissues is common following clinical or subclinical infection.


Assuntos
Vírus da Febre Aftosa/isolamento & purificação , Febre Aftosa/epidemiologia , Doenças dos Suínos/epidemiologia , Animais , Proteínas do Capsídeo/análise , Portador Sadio/virologia , Febre Aftosa/sangue , Febre Aftosa/prevenção & controle , Febre Aftosa/virologia , Tecido Linfoide/virologia , Orofaringe/virologia , RNA Viral/análise , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia
11.
Virology ; 468-470: 185-196, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25216088

RESUMO

Foot-and-mouth disease virus (FMDV) produces a disease in cattle characterized by vesicular lesions and a persistent infection with asymptomatic low-level production of virus in pharyngeal tissues. Here we describe the establishment of a persistently infected primary cell culture derived from bovine pharynx tissue (PBPT) infected with FMDV serotype O1 Manisa, where surviving cells were serially passed until a persistently infected culture was generated. Characterization of the persistent virus demonstrated changes in its plaque size, ability to grow in different cell lines, and change in the use of integrins as receptors, when compared with the parental virus. These results demonstrate the establishment of persistently infected PBPT cell cultures where co-adaptation has taken place between the virus and host cells. This in vitro model for FMDV persistence may help further understanding of the molecular mechanisms of the cattle carrier state.


Assuntos
Vírus da Febre Aftosa/fisiologia , Faringe/citologia , Animais , Bovinos , Células , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Fatores de Tempo , Replicação Viral
12.
Res Vet Sci ; 96(2): 396-405, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24548596

RESUMO

In order to characterize foot-and-mouth disease virus (FMDV) infection dynamics in pigs, two simulated-natural inoculation systems were developed and evaluated. Intra-oropharyngeal (IOP) and intra-nasopharyngeal (INP) inoculation both enabled precise control of dose and timing of inoculation while simulating field exposure conditions. There were substantial differences between outcomes of infections by the two routes. IOP inoculation resulted in consistent and synchronous infection, whereas INP inoculation at similar doses resulted in delayed, or completely absent infection. All pigs that developed clinical infection had detectable levels of FMDV RNA in their oropharynx directly following inoculation. Furthermore, FMDV antigens were localized to the oropharyngeal tonsils suggesting a role in early infection. The utility of IOP inoculation was further demonstrated in a vaccine-challenge experiment. Thus, the novel system of IOP inoculation described herein, offers a valid alternative to traditionally used systems for FMDV inoculation of pigs, applicable for experimental studies of FMDV pathogenesis and vaccinology.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , Doenças dos Suínos/virologia , Vacinas Virais/imunologia , Viremia/veterinária , Animais , Febre Aftosa/sangue , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Imuno-Histoquímica/veterinária , Masculino , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Suínos , Doenças dos Suínos/imunologia , Viremia/sangue , Viremia/imunologia , Viremia/virologia
13.
Genet Mol Res ; 13(1): 2160-5, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24535898

RESUMO

Preeclampsia is a pregnancy-specific disorder in humans and a major cause of maternal and neonatal morbidity and mortality. Increasing evidence suggests that oxidative stress plays an important role in the pathogenesis of preeclampsia. The aim of this study was to investigate the relationship between null alleles of the glutathione S-transferases (GST) M1 and T1 genes and the risk of preeclampsia. This case-control study involved 112 preeclamptic and 233 normoevolutive pregnant women. The null polymorphisms were genotyped by multiplex polymerase chain reaction (PCR). Our results showed an increased risk of preeclampsia in patients with the GSTT1 null genotype [odds ratio (OR) = 2.21; 95% confidence interval (CI) = 1.14-4.27; P = 0.018]. Our data further showed that a combination of deletion genotypes of the GSTM1 and GSTT1 genes conferred an even higher risk of preeclampsia (OR = 4.56, 95%CI = 1.59-13.09; P = 0.005). Our results provide the first evidence suggesting that a GSTT1 null polymorphism might be associated with preeclampsia in the Mexican mestizo population, and that this risk increases with the combination of both GSTT1 and GSTM1 null polymorphisms.


Assuntos
Predisposição Genética para Doença , Glutationa Transferase/genética , Polimorfismo Genético , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/genética , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , México/epidemiologia , Razão de Chances , Gravidez , Risco , Adulto Jovem
14.
J Virol ; 88(5): 2737-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24352458

RESUMO

UNLABELLED: Nonstructural protein 3A of foot-and-mouth disease virus (FMDV) is a partially conserved protein of 153 amino acids in most FMDVs examined to date. The role of 3A in virus growth and virulence within the natural host is not well understood. Using a yeast two-hybrid approach, we identified cellular protein DCTN3 as a specific host binding partner for 3A. DCTN3 is a subunit of the dynactin complex, a cofactor for dynein, a motor protein. The dynactin-dynein duplex has been implicated in several subcellular functions involving intracellular organelle transport. The 3A-DCTN3 interaction identified by the yeast two-hybrid approach was further confirmed in mammalian cells. Overexpression of DCTN3 or proteins known to disrupt dynein, p150/Glued and 50/dynamitin, resulted in decreased FMDV replication in infected cells. We mapped the critical amino acid residues in the 3A protein that mediate the protein interaction with DCTN3 by mutational analysis and, based on that information, we developed a mutant harboring the same mutations in O1 Campos FMDV (O1C3A-PLDGv). Although O1C3A-PLDGv FMDV and its parental virus (O1Cv) grew equally well in LFBK-αvß6, O1C3A-PLDGv virus exhibited a decreased ability to replicate in primary bovine cell cultures. Importantly, O1C3A-PLDGv virus exhibited a delayed disease in cattle compared to the virulent parental O1Campus (O1Cv). Virus isolated from lesions of animals inoculated with O1C3A-PLDGv virus contained amino acid substitutions in the area of 3A mediating binding to DCTN3. Importantly, 3A protein harboring similar amino acid substitutions regained interaction with DCTN3, supporting the hypothesis that DCTN3 interaction likely contributes to virulence in cattle. IMPORTANCE: The objective of this study was to understand the possible role of a FMD virus protein 3A, in causing disease in cattle. We have found that the cellular protein, DCTN3, is a specific binding partner for 3A. It was shown that manipulation of DCTN3 has a profound effect in virus replication. We developed a FMDV mutant virus that could not bind DCTN3. This mutant virus exhibited a delayed disease in cattle compared to the parental strain highlighting the role of the 3A-DCTN3 interaction in virulence in cattle. Interestingly, virus isolated from lesions of animals inoculated with mutant virus contained mutations in the area of 3A that allowed binding to DCTN3. This highlights the importance of the 3A-DCTN3 interaction in FMD virus virulence and provides possible mechanisms of virus attenuation for the development of improved FMD vaccines.


Assuntos
Vírus da Febre Aftosa/fisiologia , Febre Aftosa/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Linhagem Celular , Complexo Dinactina , Vírus da Febre Aftosa/patogenicidade , Expressão Gênica , Humanos , Espaço Intracelular/metabolismo , Proteínas Associadas aos Microtúbulos/química , Dados de Sequência Molecular , Mutação , Ligação Proteica , Mapeamento de Interação de Proteínas , Alinhamento de Sequência , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Virulência , Replicação Viral
15.
J Virol ; 87(12): 6794-803, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23576498

RESUMO

Foot-and-mouth disease virus (FMDV), the causative agent of foot-and-mouth disease, is an Aphthovirus within the Picornaviridae family. During infection with FMDV, several host cell membrane rearrangements occur to form sites of viral replication. FMDV protein 2C is part of the replication complex and thought to have multiple roles during virus replication. To better understand the role of 2C in the process of virus replication, we have been using a yeast two-hybrid approach to identify host proteins that interact with 2C. We recently reported that cellular Beclin1 is a natural ligand of 2C and that it is involved in the autophagy pathway, which was shown to be important for FMDV replication. Here, we report that cellular vimentin is also a specific host binding partner for 2C. The 2C-vimentin interaction was further confirmed by coimmunoprecipitation and immunofluorescence staining to occur in FMDV-infected cells. It was shown that upon infection a vimentin structure forms around 2C and that this structure is later resolved or disappears. Interestingly, overexpression of vimentin had no effect on virus replication; however, overexpression of a truncated dominant-negative form of vimentin resulted in a significant decrease in viral yield. Acrylamide, which causes disruption of vimentin filaments, also inhibited viral yield. Alanine scanning mutagenesis was used to map the specific amino acid residues in 2C critical for vimentin binding. Using reverse genetics, we identified 2C residues that are necessary for virus growth, suggesting that the interaction between FMDV 2C and cellular vimentin is essential for virus replication.


Assuntos
Proteínas de Transporte/metabolismo , Células Epiteliais/virologia , Vírus da Febre Aftosa/fisiologia , Vimentina/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Animais , Proteínas de Transporte/genética , Linhagem Celular , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/metabolismo , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Técnicas do Sistema de Duplo-Híbrido , Vimentina/genética , Proteínas não Estruturais Virais/genética
16.
J Virol ; 86(22): 12080-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22933281

RESUMO

Foot-and-mouth disease virus (FMDV), the causative agent of foot-and-mouth disease, is an Apthovirus within the Picornaviridae family. Replication of the virus occurs in association with replication complexes that are formed by host cell membrane rearrangements. The largest viral protein in the replication complex, 2C, is thought to have multiple roles during virus replication. However, studies examining the function of FMDV 2C have been rather limited. To better understand the role of 2C in the process of virus replication, we used a yeast two-hybrid approach to identify host proteins that interact with 2C. We report here that cellular Beclin1 is a specific host binding partner for 2C. Beclin1 is a regulator of the autophagy pathway, a metabolic pathway required for efficient FMDV replication. The 2C-Beclin1 interaction was further confirmed by coimmunoprecipitation and confocal microscopy to actually occur in FMDV-infected cells. Overexpression of either Beclin1 or Bcl-2, another important autophagy factor, strongly affects virus yield in cell culture. The fusion of lysosomes to autophagosomes containing viral proteins is not seen during FMDV infection, a process that is stimulated by Beclin1; however, in FMDV-infected cells overexpressing Beclin1 this fusion occurs, suggesting that 2C would bind to Beclin1 to prevent the fusion of lysosomes to autophagosomes, allowing for virus survival. Using reverse genetics, we demonstrate here that modifications to the amino acids in 2C that are critical for interaction with Beclin1 are also critical for virus growth. These results suggest that interaction between FMDV 2C and host protein Beclin1 could be essential for virus replication.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Vírus da Febre Aftosa/metabolismo , Proteínas de Membrana/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Sequência de Aminoácidos , Animais , Autofagia , Proteína Beclina-1 , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Cricetinae/metabolismo , Células Epiteliais/citologia , Vírus da Febre Aftosa/genética , Biblioteca Gênica , Humanos , Glândulas Mamárias Humanas/metabolismo , Modelos Genéticos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Plasmídeos/metabolismo , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Homologia de Sequência de Aminoácidos , Técnicas do Sistema de Duplo-Híbrido
17.
Phys Rev Lett ; 108(15): 158104, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22587290

RESUMO

Often groups need to meet repeatedly before a decision is reached. Hence, most individual decisions will be contingent on decisions taken previously by others. In particular, the decision to cooperate or not will depend on one's own assessment of what constitutes a fair group outcome. Making use of a repeated N-person prisoner's dilemma, we show that reciprocation towards groups opens a window of opportunity for cooperation to thrive, leading populations to engage in dynamics involving both coordination and coexistence, and characterized by cycles of cooperation and defection. Furthermore, we show that this process leads to the emergence of fairness, whose level will depend on the dilemma at stake.

18.
Transbound Emerg Dis ; 58(4): 358-71, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21418546

RESUMO

Experimental studies of foot-and-mouth disease (FMD) in feral swine are limited, and data for clinical manifestations and disease transmissibility are lacking. In this report, feral and domestic swine were experimentally infected with FMDV (A24-Cruzeiro), and susceptibility and virus transmission were studied. Feral swine were proved to be highly susceptible to A-24 Cruzeiro FMD virus by intradermal inoculation and by contact with infected domestic and feral swine. Typical clinical signs in feral swine included transient fever, lameness and vesicular lesions in the coronary bands, heel bulbs, tip of the tongue and snout. Domestic swine exhibited clinical signs of the disease within 24 h after contact with feral swine, whereas feral swine did not show clinical signs of FMD until 48 h after contact with infected domestic and feral swine. Clinical scores of feral and domestic swine were comparable. However, feral swine exhibited a higher tolerance for the disease, and their thicker, darker skin made vesicular lesions difficult to detect. Virus titration of oral swabs showed that both feral and domestic swine shed similar amounts of virus, with levels peaking between 2 to 4 dpi/dpc (days post-inoculation/days post-contact). FMDV RNA was intermittently detectable in the oral swabs by real-time RT-PCR of both feral and domestic swine between 1 and 8 dpi/dpc and in some instances until 14 dpi/12 dpc. Both feral and domestic swine seroconverted 6-8 dpi/dpc as measured by 3ABC antibody ELISA and VIAA assays. FMDV RNA levels in animal room air filters were similar in feral and domestic swine animal rooms, and were last detected at 22 dpi, while none were detectable at 28 or 35 dpi. The FMDV RNA persisted in domestic and feral swine tonsils up to 33-36 dpi/dpc, whereas virus isolation was negative. Results from this study will help understand the role feral swine may play in sustaining an FMD outbreak, and may be utilized in guiding surveillance, epidemiologic and economic models.


Assuntos
Febre Aftosa/transmissão , Doenças dos Suínos/epidemiologia , Microbiologia do Ar , Animais , Animais Selvagens , Suscetibilidade a Doenças , Feminino , Febre Aftosa/patologia , Febre Aftosa/virologia , Vírus da Febre Aftosa/isolamento & purificação , Masculino , Suínos , Doenças dos Suínos/patologia , Doenças dos Suínos/virologia , Fatores de Tempo
19.
Vet Pathol ; 47(6): 1048-63, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20587691

RESUMO

To characterize the early events of foot-and-mouth disease virus (FMDV) infection in cattle subsequent to simulated natural exposure, 16 steers were aerosol inoculated with FMDV and euthanized at various times. Samples were collected from each steer antemortem (serum, nasal swabs, and oral swabs) and postmortem (up to 40 tissues per animal) and screened for FMDV by virus isolation and for FMDV RNA by real-time reverse transcription polymerase chain reaction. Tissues that tested positive for FMDV or viral RNA were examined by immunohistochemistry and multichannel immunofluorescence microscopy. In previremic steers, FMDV was most consistently localized to nasopharyngeal tissues, thereby indicating this region as the most important site of primary viral replication. The earliest site of microscopic localization of FMDV antigens was the lymphoid follicle-associated epithelium of the pharyngeal mucosa-associated lymphoid tissue of the nasopharynx at 6 hours postaerosolization. At early time points after aerosol inoculation, viral antigens colocalized with cytokeratin-positive pharyngeal epithelial cells; intraepithelial FMDV-negative, MHCII/CD11c-double-positive dendritic cells were present in close proximity to FMDV-positive cells. Onset of viremia coincided with marked increase of viral loads in pulmonary tissues and with substantial decrease of viral detection in nasopharyngeal tissues. These data indicate that subsequent to aerogenous exposure to FMDV, the temporally defined critical pathogenesis events involve (1) primary replication in epithelial cells of the pharyngeal mucosa-associated lymphoid tissue crypts and (2) subsequent widespread replication in pneumocytes in the lungs, which coincides with (3) the establishment of sustained viremia.


Assuntos
Doenças dos Bovinos/virologia , Febre Aftosa/patologia , Nasofaringe/virologia , Administração por Inalação , Aerossóis , Animais , Bovinos , Doenças dos Bovinos/patologia , Progressão da Doença , Imunofluorescência/veterinária , Pulmão/patologia , Pulmão/virologia , Masculino , Nasofaringe/patologia , RNA Viral/metabolismo , Carga Viral/veterinária , Viremia/patologia , Viremia/veterinária , Viremia/virologia
20.
J Phys Condens Matter ; 22(3): 035501, 2010 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21386290

RESUMO

We investigate the feasibility of assembling the exceptionally stable isovalent X@Si(16) (X = Ti, Zr and Hf) nanoparticles to form new bulk materials. We use first-principles density functional theory. Our results predict the formation of stable, wide band-gap materials crystallizing in HCP structures in which the cages bind weakly, similar to fullerite. This study suggests new pathways through which endohedral cage clusters may constitute a viable means toward the production of synthetic materials with pre-defined physical and chemical properties.

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