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1.
J Virol ; 97(7): e0046923, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37310242

RESUMEN

Due to increased and broadened screening efforts, the last decade has seen a rapid expansion in the number of viral species classified into the Hepacivirus genus. Conserved genetic features of hepaciviruses suggest that they have undergone specific adaptation and have evolved to hijack similar host proteins for efficient propagation in the liver. Here, we developed pseudotyped viruses to elucidate the entry factors of GB virus B (GBV-B), the first hepacivirus described in an animal after hepatitis C virus (HCV). GBV-B-pseudotyped viral particles (GBVBpp) were shown to be uniquely sensitive to the sera of tamarins infected with GBV-B, validating their usefulness as a surrogate for GBV-B entry studies. We screened GBVBpp infection of human hepatoma cell lines that were CRISPR/Cas9 engineered to ablate the expression of individual HCV receptors/entry factors and found that claudin-1 is essential for GBV-B infection, indicating the GBV-B and HCV share an entry factor. Our data suggest that claudin-1 facilitates HCV and GBV-B entry through distinct mechanisms since the former requires the first extracellular loop and the latter is reliant on a C-terminal region containing the second extracellular loop. The observation that claudin-1 is an entry factor shared between these two hepaciviruses suggests that the tight junction protein is of fundamental mechanistic importance during cell entry. IMPORTANCE Hepatitis C virus (HCV) is a major public health burden; approximately 58 million individuals have chronic HCV infection and are at risk of developing cirrhosis and liver cancer. To achieve the World Health Organization's target of eliminating hepatitis by 2030, new therapeutics and vaccines are needed. Understanding how HCV enters cells can inform the design of new vaccines and treatments targeting the first stage of infection. However, the HCV cell entry mechanism is complex and has been sparsely described. Studying the entry of related hepaciviruses will increase the knowledge of the molecular mechanisms of the first stages of HCV infection, such as membrane fusion, and inform structure-guided HCV vaccine design; in this work, we have identified a protein, claudin-1, that facilitates the entry of an HCV-related hepacivirus but with a mechanism not described for HCV. Similar work on other hepaciviruses may unveil a commonality of entry factors and, possibly, new mechanisms.


Asunto(s)
Virus GB-B , Hepatitis C , Animales , Humanos , Hepacivirus/genética , Claudina-1/genética
2.
Plant Dis ; : PDIS03240546RE, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-38853335

RESUMEN

In recent years, kiwifruit viral diseases have become increasingly prevalent in kiwifruit-producing regions of China, significantly impacting both the yield and quality of kiwifruit. This has emerged as a significant constraint on the healthy and sustainable development of the kiwifruit industry. The use of virus-free propagation materials has been proven the most effective strategy for controlling plant viral diseases. In the present study, shoot tip culture, shoot tip cryotherapy, and their combinations with thermotherapy were established to eradicate Actinidia virus A (AcVA), Actinidia virus B (AcVB), and Actinidia chlorotic ringspot-associated virus (AcCRaV) from Actinidia macrosperma. Additionally, the impact of shoot tip size on virus eradication was evaluated. Among the three confirmed viruses, regardless of the procedure, AcVB was the easiest to eradicate, followed by AcVA and AcCRaV. Combining thermotherapy with shoot tip culture or cryotherapy resulted in a higher virus-free frequency (up to 27.3 and 50%, respectively) than shoot tip culture or cryotherapy alone (0 to 20%). Notably, the combination of thermotherapy and 0.5- to 1-mm shoot tip cryotherapy was shown to be the most effective protocol for virus eradication from A. macrosperma, which produced 50% of regenerated shoots free from all the tested viruses. To the best of our knowledge, this is the first report on virus elimination from kiwifruit infected with multiple viruses based on conventional shoot tip culture and shoot tip cryotherapy.

3.
J Med Virol ; 95(7): e28943, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37436779

RESUMEN

A proportion of chronic hepatitis B virus (HBV) carriers with normal alanine transaminase (ALT) present with significant liver histological changes (SLHC). To construct a noninvasive nomogram model to identify SLHC in chronic HBV carriers with different upper limits of normal (ULNs) for ALT. The training cohort consisted of 732 chronic HBV carriers who were stratified into four sets according to different ULNs for ALT: chronic HBV carriers I, II, III, and IV. The external validation cohort comprised 277 chronic HBV carriers. Logistic regression and least absolute shrinkage and selection operator analyses were applied to develop a nomogram model to predict SLHC. A nomogram model-HBGP (based on hepatitis B surface antigen, gamma-glutamyl transpeptidase, and platelet count) demonstrated good performance in diagnosing SLHC with area under the curve (AUCs) of 0.866 (95% confidence interval [CI]: 0.839-0.892) and 0.885 (95% CI: 0.845-0.925) in the training and validation cohorts, respectively. Furthermore, HBGP displayed high diagnostic values for SLHC with AUCs of 0.866 (95% CI: 0.839-0.892), 0.868 (95% CI: 0.838-0.898), 0.865 (95% CI: 0.828-0.901), and 0.853 (95% CI: 0.798-0.908) in chronic HBV carriers I, II, III, and IV, respectively. Additionally, HBGP showed greater ability in predicting SLHC compared with the existing predictors. HBGP has shown high predictive performance for SLHC, and thus may lead to an informed decision on the initiation of antiviral treatment.


Asunto(s)
Hepatitis B Crónica , Humanos , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/patología , Nomogramas , Virus de la Hepatitis B/genética , Cirrosis Hepática/diagnóstico , Alanina Transaminasa , ADN Viral , Antígenos e de la Hepatitis B
4.
Virol J ; 19(1): 182, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36357910

RESUMEN

BACKGROUND: Chrysanthemum virus B (CVB), a key member of the genus Carlavirus, family Betaflexiviridae, causes severe viral diseases in chrysanthemum (Chrysanthemum morifolium) plants worldwide. However, information on the mechanisms underlying the response of chrysanthemum plants to CVB is scant. METHODS: Here, an integrated next-generation sequencing and comparative transcriptomic analysis of chrysanthemum leaves was conducted to explore the molecular response mechanisms of plants to a Chinese isolate of CVB (CVB-CN) at the molecular level. RESULTS: In total, 4934 significant differentially expressed genes (SDEGs) were identified to respond to CVB-CN, of which 4097 were upregulated and 837 were downregulated. Gene ontology and functional classification showed that the majority of upregulated SDEGs were categorized into gene cohorts involved in plant hormone signal transduction, phenylpropanoid and flavonoid biosynthesis, and ribosome metabolism. Enrichment analysis demonstrated that ethylene pathway-related genes were significantly upregulated following CVB-CN infection, indicating a strong promotion of ethylene biosynthesis and signaling. Furthermore, disruption of the ethylene pathway in Nicotiana benthamiana, a model plant, using virus-induced gene silencing technology rendered them more susceptible to cysteine-rich protein of CVB-CN induced hypersensitive response, suggesting a crucial role of this pathway in response to CVB-CN infection. CONCLUSION: This study provides evidence that ethylene pathway has an essential role of plant in response to CVB and offers valuable insights into the defense mechanisms of chrysanthemum against Carlavirus.


Asunto(s)
Carlavirus , Chrysanthemum , Chrysanthemum/genética , Chrysanthemum/metabolismo , Carlavirus/genética , Transcriptoma , Etilenos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Hojas de la Planta , China , Regulación de la Expresión Génica de las Plantas
5.
Plant Dis ; 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33908792

RESUMEN

Gynura japonica (Thunb.) Juel [Asteraceae; syn: G. segetum (Lour.) Merr] is an important perennial medicinal herb used in China for topical treatment of trauma injuries (Lin et al. 2003). It grows naturally in the southern provinces of China and is also sometimes cultivated. During 2018-2020, wild G. japonica plants exhibiting chlorotic spots and mosaic symptoms were observed in Zhejiang province, China. To identify the possible causal agents of the disease, a single symptomatic leaf sample was collected in August 2019 and sent to Zhejiang Academy of Agricultural Sciences (Hangzhou, China) for next generation sequencing (NGS). Total RNAs extracted with TRIzol (Invitrogen, Carlsbad, USA) were subjected to high throughput sequencing on the Illumina NovaSeq 6000 platform with PE150bp and data analysis was performed by CLC Genomic Workbench 11 with default parameters (QIAGEN, Hilden, Germany). A total of 37,314,080 paired-end reads were obtained, and 11,785 contigs (961 to 10,964 bp) were generated and compared with sequences in GenBank using BLASTn or BLASTx. Of the total of 12 viral-related contigs obtained, one with a length of 6,442 nt mapped to the genomic RNA of ASGV (MN495979), seven contigs with lengths ranging from 1,034 to 2,901 nt mapped to Chrysanthemum virus B (CVB), and four mapped to broad bean wilt virus 2 (BBWV2), a virus which is known to infect G. procumbens (Kwak et al. 2017). To further confirm the presence of ASGV and CVB, primers were designed and the complete nucleotide sequences of both viruses were amplified from the original NGS sample using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) according to the manufacturer's instructions (Tiosbio, Beijing, China). BLASTn analysis revealed that the complete 6,451 nt sequence of ASGV (GenBank accession No. MW259059) shared the highest identity (81.2%) with a Chinese isolate of ASGV from citrus (MN495979). The two isolates grouped with another Chinese isolate (from pear) in phylogenetic analysis. The predicted coat protein of the virus had the highest nt identity of 93.7% (96.2% amino acid sequence identity) with that of the Chinese ASGV isolate XY from apple (KX686100). The complete genomes of two distinct molecular variants of CVB (both 8,987 nt in length) were also obtained from this sample (GenBank accession Nos. MW269552, MW269553). They shared 86.8% nt identity with each other and had 81.1% and 82.1% identity to the only known complete sequence of CVB from chrysanthemum (AB245142). Ten additional wild G. japonica plants with mosaic symptoms were collected randomly during 2019-2020 from Hangzhou (n=6) and Ningbo (n=4) in Zhejiang province and tested by RT-PCR with specific primer pairs to detect BBWV2, ASGV and CVB. RT-PCR and subsequent sequencing revealed that these three viruses were present in all the samples tested, indicating that co-infection of G. japonica by ASGV, CVB and BBWV2 is common. CVB mainly infects chrysanthemum (Singh et al. 2012), while ASGV is known as a pathogen of various fruit trees especially in the family Rosaceae, although there are recent reports that it can also infect some plants in Gramineae, Asparagaceae and Nelumbonaceae (Bhardwaj et al. 2017; Chen et al. 2019; He et al. 2019). Our results provide the first report that Gynura is a natural host of CVB and ASGV. Further surveys and biological studies are underway to evaluate the importance of Gynura as a virus reservoir for epidemics among the various hosts.

6.
BMC Gastroenterol ; 19(1): 101, 2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-31226942

RESUMEN

BACKGROUND: The preventive effects of antiviral therapy to reduce rebleeding rate in patients with hepatitis B-related cirrhosis undergoing endoscopic treatment have not yet been reported. METHODS: In this retrospective cohort study, 1139 patients with chronic hepatitis B with first acute variceal bleeding after endoscopic therapy from September 2008 to December 2017 were included. Among them, 923 who received and 216 who did not receive antiviral therapy were followed up for rebleeding. Cumulative rebleeding rate was calculated using the Kaplan-Meier method. Univariate and multivariate logistic regression analyses were performed to estimate the effects of antiviral therapy on rebleeding risk. The propensity score matched method and inverse probability of treatment weighting analysis were used to calculate the rebleeding rate between the antiviral and non-antiviral groups. RESULTS: The rebleeding rates were 40.5, 60.7, 72.6, and 89.2% in antiviral group at 1, 2, 3, and 5 years, respectively. The corresponding rebleeding rates in the non-antiviral group were 54.2, 72.4, 84.4, and 93.3%, respectively. The multivariate logistic regression analysis revealed that antiviral therapy was an independent protective factor associated with rebleeding. CONCLUSION: Antiviral treatment significantly reduced rebleeding rate in patients with HBV-related cirrhosis who received endoscopic treatment after the first variceal bleeding.


Asunto(s)
Antivirales/uso terapéutico , Endoscopía/efectos adversos , Várices Esofágicas y Gástricas/prevención & control , Hemorragia Gastrointestinal/prevención & control , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/cirugía , Complicaciones Posoperatorias/prevención & control , Enfermedad Aguda , Várices Esofágicas y Gástricas/epidemiología , Várices Esofágicas y Gástricas/virología , Femenino , Hemorragia Gastrointestinal/epidemiología , Hemorragia Gastrointestinal/virología , Hepatitis B Crónica/virología , Humanos , Estimación de Kaplan-Meier , Cirrosis Hepática/virología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/virología , Puntaje de Propensión , Factores Protectores , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
7.
Pharmacology ; 103(3-4): 136-142, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30602153

RESUMEN

To investigate the effect of Tanshinone IIA (TSA) on viral myocarditis (VMC). VMC animal model was established using BALB/c mice by intraperitoneally injecting Coxsackie virus B3 (CVB3). The mice were randomly divided into control group, model group, and TSA group. We detected the survival rate, the heart weight to body weight (HW/BW) ratio and hemodynamic and cardiac function parameters. The pathological features of VMC were measured through H&E staining. The expression of serum enzyme, inflammatory cytokines, and T helper (Th)1/Th2 markers was also investigated. TSA remarkably alleviated CVB3-caused myocardial injury, decreased the HW/BW ratio, and improved survival rate. TSA obviously improved hemodynamic parameters and reversed the damage to the heart pump function. Furthermore, the serum levels of lactate dehydrogenase, creatine kinase, and Th1 cytokines in the TSA group were significantly lower than those in the VMC group, and TSA treatment significantly improved the pathological condition. The interferon-gamma (IFN-γ) and interleukin-2 (IL-2) levels in VMC model group was higher than control group, and lower levels of IL-4 and IL-10 were identified. However, TSA treatment elevated IL-4 and IL-10 levels and decreased IFN-γ and IL-2 levels. TSA could effectively protect the myocardium against CVB3-induced myocarditis by the inhibition of inflammation and modulation Th1/Th2 balance in mice.


Asunto(s)
Abietanos/farmacología , Antiinflamatorios/farmacología , Infecciones por Coxsackievirus/prevención & control , Enterovirus/patogenicidad , Miocarditis/prevención & control , Miocardio , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Animales , Infecciones por Coxsackievirus/sangre , Infecciones por Coxsackievirus/inmunología , Infecciones por Coxsackievirus/virología , Citocinas/sangre , Modelos Animales de Enfermedad , Enterovirus/inmunología , Mediadores de Inflamación/sangre , Masculino , Ratones Endogámicos BALB C , Miocarditis/sangre , Miocarditis/inmunología , Miocarditis/virología , Miocardio/inmunología , Miocardio/metabolismo , Miocardio/patología , Células TH1/inmunología , Células TH1/metabolismo , Células TH1/virología , Balance Th1 - Th2/efectos de los fármacos , Células Th2/inmunología , Células Th2/metabolismo , Células Th2/virología
8.
Endocr J ; 65(1): 129-132, 2018 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-28966225

RESUMEN

Drug-induced hypersensitivity syndrome (DIHS) is a severe systemic adverse drug reaction. Previous studies showed that DIHS is associated with the onset of fulminant type 1 diabetes mellitus (FT1D). Although genetic background and abnormalities in immune response or viral infection are considered to be associated with pathogenesis of FT1D, it remains unclear whether virus infection and specific human leukocyte antigen (HLA) typing are involved in DIHS-associated FT1D. Here, we report a case of a 78-year-old female patient with FT1D after DIHS treatment. She was diagnosed as DIHS caused by carbamazepine, and treatment with predonisolone was initiated. After 46 days from the occurrence of DIHS, she was admitted to our hospital because of type 1 diabetes mellitus and diabetic ketoacidosis. Although her Hemoglobin A1c (HbA1c) was elevated by predonisolone treatment (HbA1c: 9.2%), we diagnosed her as fulminant type 1 diabetes mellitus considering the abrupt onset of the ketoacidosis. Her general condition was improved by treatment with fluid infusion and insulin administration. During her clinical course, the infection of coxsackie B4 virus was observed. In addition, the examination of HLA typing showed HLA-A24 haplotype. These findings suggest that the coxsackie B4 virus infection may be involved in the pathogenesis of DIHS-induced FT1D, and that HLA-A24 haplotype might relate to DIHS-associated FT1D.


Asunto(s)
Infecciones por Coxsackievirus/complicaciones , Diabetes Mellitus Tipo 1/complicaciones , Síndrome de Hipersensibilidad a Medicamentos/complicaciones , Enterovirus Humano B/aislamiento & purificación , Antígeno HLA-A24/sangre , Anciano , Antiinflamatorios/uso terapéutico , Anticonvulsivantes/efectos adversos , Blefaroespasmo/complicaciones , Blefaroespasmo/tratamiento farmacológico , Carbamazepina/efectos adversos , Terapia Combinada , Infecciones por Coxsackievirus/sangre , Infecciones por Coxsackievirus/virología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/virología , Cetoacidosis Diabética/prevención & control , Síndrome de Hipersensibilidad a Medicamentos/sangre , Síndrome de Hipersensibilidad a Medicamentos/tratamiento farmacológico , Síndrome de Hipersensibilidad a Medicamentos/virología , Monitoreo de Drogas , Femenino , Humanos , Japón , Prednisolona/uso terapéutico , Resultado del Tratamiento
9.
Artículo en Inglés | MEDLINE | ID: mdl-28617973

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) infection during pregnancy is associated with perinatal complications and poor maternal and fetal outcomes. There is a lack of reports on HBV infection screening, prophylaxis, and/or treatment in preconception period among women planning a pregnancy. This study is to investigate the prevalence and demographic characteristics of HBV infection among rural women of reproductive age planning pregnancy within 6 months, in different geographical regions of China. METHODS: A population-based, cross-sectional, sero-survey of HBV infection among women intending to get pregnant within 6 months was carried out as a part of the National Free Preconception Health Examination Project covering 31 provinces in mainland China between 2010-12. General information (age, residence status, race, education, and occupation), HBV infection and vaccination history was collected. Results of HBV serological test panel were recorded for analysis. RESULTS: Of 2 120 131 women, 2 028 361 (95.7%) samples of HBV serology were available for analysis. Participating women were of young age (median 28.1 years), mostly engaged in agricultural activities (78.1%), and had high school education or lower (89.6%). The overall prevalence of HBsAg sero-positivity was 4.9%, which corresponds to an intermediate epidemic, with a wide geographical variation that ranged from 1.1% in Shanxi to 13.0% in Tibet. 90.1% women were susceptible to HBV with a 24.5% self-reported HBV vaccination rate. CONCLUSIONS: Significant regional differences in HBV prevalence, and a vast majority of women of childbearing age being susceptible to HBV, calls for a targeted HBV screening and vaccination strategy for women and their offspring in rural China.

11.
Pediatr Int ; 59(5): 627-632, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28402006

RESUMEN

Herein we describe the case of a 1-month-old boy with acute viral myocarditis, who presented with two kinds of paroxysmal supraventricular tachycardia, and who was cured after medical treatment. He was brought to the emergency room with poor feeding due to fever. On the third day of hospitalization, a narrow QRS tachycardia (180-200 beats/min) was detected. Echocardiography showed a high echoic area at the atrial septum around the atrioventricular node. The patient was clinically diagnosed with acute myocarditis. The narrow QRS tachycardia was diagnosed as incessant junctional ectopic tachycardia. The patient was treated with propranolol and landiolol. The frequency of the tachycardia decreased, but a different narrow QRS tachycardia was detected on the 15th day of hospitalization on electrocardiogram (220 beats/min), which was ascribed to atrioventricular nodal re-entrant tachycardia. Atenolol was effective for the tachycardia. At 2 years follow up, cardiac function was normal and tachycardia had not recurred.


Asunto(s)
Infecciones por Coxsackievirus/diagnóstico , Enterovirus Humano B/aislamiento & purificación , Miocarditis/diagnóstico , Taquicardia Supraventricular/etiología , Infecciones por Coxsackievirus/complicaciones , Humanos , Lactante , Masculino , Miocarditis/complicaciones , Miocarditis/virología , Taquicardia Ectópica de Unión/diagnóstico , Taquicardia Ectópica de Unión/etiología , Taquicardia Supraventricular/diagnóstico
12.
Virol J ; 13(1): 197, 2016 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-27899161

RESUMEN

BACKGROUND: The potential involvement of viruses in inflammatory airway disease (IAD) was previously investigated through either serology or PCR from nasopharyngeal swabs (NS). The aims of this study were to determine the prevalence and incidence of viral genome detection by qPCR in the equine airways, and their association with respiratory clinical signs. METHODS: Both NS and tracheal washes (TW) were collected monthly on 52 Standardbred racehorses at training, over 27 consecutive months (581 samples). Equid herpesviruses (EHV)-1, -4, -2 and -5, equine rhinitis virus-A and -B (ERBV), equine adenovirus-1 and -2, equine coronavirus and equine influenza virus were systematically investigated in both NS and TW. Nasal discharge, coughing, tracheal mucus score and TW neutrophil proportions were simultaneously recorded. RESULTS: Genome for 7/10 viruses were detected at least once throughout the study; up to 4 different viruses being also concomitantly detected. Monthly incidence in TW was respectively 27.9% (EHV-5), 24.8% (EHV-2), 7.1% (ERBV), 3.8% (EHV-4), 1.9% (EAdV1) and 0.2% (EHV-1; ERAV). Neither agreement nor correlation between NS and TW was found for respectively genome detection and viral loads. Detection of viral genome in NS was not associated with any clinical sign. Coughing was significantly associated with TW detection of EHV-2 DNA (OR 3.1; P = 0.01) and ERBV RNA (OR 5.3; P < 0.001). Detection of EHV-2 DNA in TW was also significantly associated with excess tracheal mucus (OR 2.1; P = 0.02). CONCLUSIONS: Detection and quantification of EHV-2 and ERBV by qPCR in TW, but not in NS, should be considered when investigating horses with IAD.


Asunto(s)
Enfermedades de los Caballos/diagnóstico , Inflamación/veterinaria , Técnicas de Diagnóstico Molecular/métodos , Infecciones del Sistema Respiratorio/veterinaria , Medicina Veterinaria/métodos , Virosis/veterinaria , Virus/aislamiento & purificación , Animales , Femenino , Caballos , Incidencia , Inflamación/diagnóstico , Inflamación/epidemiología , Masculino , Nasofaringe/virología , Prevalencia , ARN Viral/genética , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/epidemiología , Tráquea/virología , Virosis/epidemiología , Virosis/virología , Virus/clasificación , Virus/genética
13.
Microbiol Immunol ; 60(1): 26-34, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26634303

RESUMEN

The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (<200 copies/mL), the viral RNA loads in plasma were detectable intermittently during the observation period. Of note, the chimeric RNA was found in the pellet fraction obtained by ultracentrifugation of the plasma at 73 weeks, indicating production of the chimeric virus. Our results will help establish a novel non-human primate model for HCV infection on the basis of the HCV/G chimera in the major framework of the HCV genome.


Asunto(s)
Virus GB-B/fisiología , Hepatitis Viral Animal/virología , Enfermedades de los Monos/virología , Platirrinos/virología , Replicación Viral/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Quimera/genética , Quimera/virología , Modelos Animales de Enfermedad , Infecciones por Flaviviridae/virología , Virus GB-B/genética , Virus GB-B/inmunología , Humanos , Datos de Secuencia Molecular , ARN Viral/genética , Vacunas contra Hepatitis Viral/inmunología , Proteínas no Estructurales Virales
14.
Pediatr Int ; 58(5): 415-417, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26711006

RESUMEN

Enterovirus focal encephalitis is a rare clinical entity that is characterized by focal neurological signs including seizure, hemiparesis, hemichorea, and headache, which are mainly followed by rapid spontaneous improvement. We herein describe the case of a 9-month-old boy who developed Coxsackie virus B5 (CVB5) focal encephalitis with seizure clusters in the eruption stage of roseola infantum-like illness, which were followed by rapid improvement and benign outcome. Lumbar puncture indicated pleocytosis, and CVB5 infection in the cerebrospinal fluid was subsequently identified on genome sequencing and virus isolation. Magnetic resonance imaging and electroencephalography showed no abnormal findings at the acute stage or on 2 month follow up. Although the pathogenesis of enterovirus focal encephalitis currently remains unclear, the pure synchronism of seizure cluster and eruption in this case suggests the involvement of local vascular impairment as the underlying pathogenesis.

15.
Liver Int ; 35 Suppl 1: 78-81, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25529091

RESUMEN

The end point of liver fibrosis in almost all chronic liver diseases including HBV chronic hepatitis is cirrhosis. Progression to cirrhosis is associated with annular deposition of fibrous tissue and vascular remodeling with a shift from a lobular to nodular organization. Although advanced liver fibrosis was previously thought to be irreversible, today there is compelling evidence that cirrhosis can be reversed if the underlying cause of liver injury is eliminated. Indeed, most clinical trials with antiviral therapy and histological follow-up have shown that fibrosis can regress and that in some cases even cirrhosis can reverse following long-term HBV-DNA suppression, although the return to a fully normal liver is rarely observed and difficult to prove. Nevertheless, a marked percentage of cirrhosis will not reverse even after effective antiviral therapy. Generally cirrhosis is more likely to regress if it is recent, there is effective and long-lasting viral suppression, an internal capacity to regenerate and no vascular thrombosis. HBV treatment in patients with cirrhosis is associated with an improved clinical outcome although there may still be a risk of hepatocellular carcinoma. Nevertheless it has not yet been determined if a favorable outcome depends on histological regression or whether the reversal of cirrhosis is merely a surrogate marker of viral suppression. The significance of the reversal of cirrhosis is still a subject of debate because neither the histological scoring systems nor non-invasive markers to evaluate the reversal of cirrhosis have been validated.


Asunto(s)
Antivirales/uso terapéutico , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B/complicaciones , Hepatitis B/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/etiología , Humanos , Cirrosis Hepática/patología , Resultado del Tratamiento
16.
Liver Int ; 35(12): 2506-13, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25939635

RESUMEN

BACKGROUND & AIMS: The outcome of HBeAg-negative chronic hepatitis B virus (HBV) patients who may remain in the inactive carrier state (IC) or progress to HBeAg-negative chronic hepatitis B may be affected by the host genetic profile. Genetic polymorphisms within not only the promoter but also the coding sequence of the interferon receptor 1 (INFAR1) gene have been associated with susceptibility to chronic HBV infection, but their role on the outcomes of HBeAg-negative patients has not been evaluated. We examined the association of INFAR1 promoter polymorphisms with the phase of chronic HBV infection in a demographically characterized Caucasian cohort of 183 consecutive HBeAg-negative chronic HBV patients. METHODS: Using a combination of conventional and allele-specific polymerase chain reactions, bidirectional sequencing and DNA-fragment analysis, we performed typing of three Single Nucleotide Polymorphisms (SNPs -568G/C, -408C/T, -3C/T) and one Variable Number Tandem Repeat [VNTR -77(GT)n] within the INFR1 promoter sequence. RESULTS: The genetic polymorphisms examined were found to be associated with the phase of HBeAg-negative chronic HBV patients. Using a multiple logistic regression model adjusting for age, gender and origin of the individuals, we found that patients with linked genotypes -408CT_-3CT were more likely to be ICs (OR = 2.42 vs. CC, P = 0.036). Also, given the partial linkage between SNP -568G/C and VNTR -77(GT)n, we found that linked genotypes -77(GT)n ≤ 8/≤8_-568GC and -77(GT)n ≤ 8/≤8_-568CC were detected more frequently among ICs (OR = 11.69, P = 0.005 and OR = 7.56, P = 0.001 vs. -77(GT)n >8/>8_-568GG respectively). CONCLUSIONS: These findings suggest that these genetic variations represent important factors associated with the clinical phase of HBeAg-negative chronic HBV infection.


Asunto(s)
Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica , Receptor de Interferón alfa y beta/genética , Adulto , Femenino , Predisposición Genética a la Enfermedad , Hepatitis B Crónica/genética , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Mutación , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas
17.
Microbiol Immunol ; 59(5): 299-304, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25753649

RESUMEN

Nodamura virus (NoV) B2, a suppressor of RNA interference, binds double stranded RNAs (dsRNAs) and small interfering RNAs (siRNAs) corresponding to Dicer substrates and products. Here, we report that the amino terminal domain of NoV B2 (NoV B2 79) specifically binds siRNAs but not dsRNAs. NoV B2 79 oligomerizes on binding to 27 nucleotide siRNA. Mutation of the residues phenylalanine49 and alanine60 to cysteine and methionine, respectively enhances the RNA binding affinity of NoV B2 79. Circular dichroism spectra demonstrated that the wild type and mutant NoV B2 79 have similar secondary structure conformations.


Asunto(s)
Nodaviridae/fisiología , ARN Interferente Pequeño/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Virales/metabolismo , Dicroismo Circular , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Nodaviridae/genética , Conformación Proteica , ARN Bicatenario/genética , ARN Bicatenario/metabolismo , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/genética , Proteínas Virales/genética
18.
Bioorg Med Chem ; 23(21): 7024-34, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26443549

RESUMEN

A library of 64 benzotriazole derivatives (17 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) were screened for antiviral activity against a panel of twelve DNA and RNA viruses. Twenty-six compounds (12 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) displayed activity against one or more viruses. CVB-5, RSV, BVDV, Sb-1 and YFV were, in decreasing order, the more frequently and effectively affected viruses; DENV-2, WNV, HIV-1 and Reo-1 were only occasionally and modestly affected, while the remaining viruses were not affected by any of the tested compounds. Worth of note were compounds 33 and 35; the former for the activity against Sb-1 (EC50=7 µM) and the latter for the large spectrum of activity including six viruses with a mean EC50=12 µM. Even more interesting were the alkanoic acids 45-48 and 50-57 for their activity against RSV and/or CVB-5. In particular, compound 56 displayed a potent and selective activity against CVB-5 with EC50=0.15 µM and SI=100, thus representing a valuable hit compound for the development of antiviral agents for the treatment of human pathologies related to this virus.


Asunto(s)
Antivirales/química , Enterovirus Humano B/fisiología , Triazoles/química , Animales , Antivirales/síntesis química , Antivirales/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cricetinae , Virus ADN/efectos de los fármacos , Virus ADN/fisiología , Perros , Enterovirus Humano B/efectos de los fármacos , Humanos , Virus ARN/efectos de los fármacos , Virus ARN/fisiología , Relación Estructura-Actividad , Triazoles/síntesis química , Triazoles/toxicidad , Replicación Viral/efectos de los fármacos
19.
J Infect Chemother ; 21(4): 302-4, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25442807

RESUMEN

The genotypes of hepatitis B virus (HBV) have a distinct geographical distribution, with HBV genotype H being very rare in East Asia, including Japan. We herein report the case of a 12-year-old Japanese female with hepatocellular carcinoma (HCC) who exhibited HBV genotype H. Notably, the HBV isolated from the patient had a deletion mutation in the pre-S2 region. The genome of HBV genotype H in the patient with HCC has not been analyzed in detail. The deletion mutations in the pre-S2 region, which may play an important role in hepatocarcinogenesis in children, can also present in genotype H.


Asunto(s)
Carcinoma Hepatocelular , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B , Neoplasias Hepáticas , Precursores de Proteínas/genética , Eliminación de Secuencia/genética , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/virología , Niño , Femenino , Hepatitis B/complicaciones , Hepatitis B/virología , Humanos , Hígado/patología , Hígado/virología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/virología
20.
J Asian Nat Prod Res ; 17(11): 1025-38, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26498463

RESUMEN

Two new norditerpenoids (1 and 2), four new sesquiterpenoids (3-6), and 22 known compounds (7-28) were isolated from an ethanolic extract of roots of Alangium chinense. The absolute configurations of 1-6 were assigned by experimental and calculated ECD spectra. The skeleton of the compounds (1 and 2) has been reported only one time so far. Compounds 1, 13, and 23 exhibited antiviral activity against coxsackie virus B3 with IC50 values of 38-67 µM. Compounds 8 and 9 displayed neuritis inhibitory activity against microglial inflammation factor, with IC50 values of 6.4 and 10.1 µM, respectively. None of the compounds were cytotoxic in the MTT assay.


Asunto(s)
Alangiaceae/química , Antivirales/aislamiento & purificación , Diterpenos/aislamiento & purificación , Enterovirus/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Antivirales/química , Antivirales/farmacología , Diterpenos/química , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Raíces de Plantas/química , Sesquiterpenos/química
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