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1.
Arch Virol ; 163(5): 1331-1335, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29392497

RESUMO

Dengue fever is one of the most common viral infections in the world. Although a vaccine against dengue virus (DENV) has been approved in several countries, this disease is still considered a public health priority worldwide. The ability of three small interfering RNAs (FG-siRNAs) targeting conserved sequences in the NS4B and NS5 regions of the DENV genome to inhibit DENV replication was tested in vitro in both Vero and C6/36 cells. The FG-siRNAs were effective against DENV-1, -3, and -4, but not DENV-2. A fourth siRNA specifically targeting the NS5 region of the DENV-2 genome (SG-siRNA) was designed and tested against two different DENV-2 strains, showing high levels of inhibition in both mammalian and insect cells.


Assuntos
Vírus da Dengue/fisiologia , RNA Interferente Pequeno/genética , Proteínas não Estruturais Virais/genética , Replicação Viral , Animais , Linhagem Celular , Chlorocebus aethiops , Vírus da Dengue/genética , Humanos , Insetos , Fases de Leitura Aberta , Células Vero
2.
Eur J Med Chem ; 128: 154-167, 2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28182988

RESUMO

Since the neuraminidase (NA) enzyme of the influenza A virus plays a key role in the process of release of new viral particles from a host cell, it is often a target for new drug design. The emergence of NA mutations, such as H275Y, has led to great resistance against neuraminidase inhibitors, including oseltamivir and zanamivir. Hence, we herein designed a set of derivatives by modifying the amine and/or carboxylic groups of oseltamivir. After being screened for their physicochemical (Lipinski's rule) and toxicological properties, the remaining compounds were submitted to molecular and theoretical studies. The docking simulations provided insights into NA recognition patterns, demonstrating that oseltamivir modified at the carboxylic moiety and coupled with anilines had higher affinity and a better binding pose for NA than the derivatives modified at the amine group. Based on these theoretical studies, the new oseltamivir derivatives may have higher affinity to mutant variants and possibly to other viral subtypes. Accordingly, two compounds were selected for synthesis, which together with their respective intermediates were evaluated for their cytotoxicity and antiviral activities. Their biological activity was then tested in cells infected with the A/Puerto Rico/916/34 (H1N1) influenza virus, and virus yield reduction assays were performed. Additionally, by measuring neuraminidase activity with the neuraminidase assay kit it was found that the compounds produced inhibitory activity on this enzyme. Finally, the infected cells were analysed with atomic force microscopy (AFM), observing morphological changes strongly suggesting that these compounds interfered with cellular release of viral particles.


Assuntos
Antivirais/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Oseltamivir/farmacologia , Animais , Antivirais/química , Chlorocebus aethiops , Simulação por Computador , Cães , Farmacorresistência Viral , Células HeLa , Humanos , Técnicas In Vitro , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Microscopia de Força Atômica , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Oseltamivir/química , Células Vero , Proteínas Virais/antagonistas & inibidores
3.
Arch Virol ; 161(6): 1639-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26935913

RESUMO

Infections caused by mumps virus (MuV) have been successfully prevented through vaccination; however, in recent years, an increasing number of mumps outbreaks have been reported within vaccinated populations. In this study, MuV was genotyped for the first time in Mexico. Saliva samples were obtained from two previously vaccinated patients in Mexico City who had developed parotitis. Viral isolation was carried out in Vero cells, and the SH and HN genes were amplified by RT-PCR. Amplicons were sequenced and compared to a set of reference sequences to identify the MuV genotype.


Assuntos
Vírus da Caxumba/genética , Caxumba/virologia , Animais , Criança , Chlorocebus aethiops , Surtos de Doenças , Feminino , Genótipo , Humanos , Masculino , México/epidemiologia , Epidemiologia Molecular , Caxumba/epidemiologia , Caxumba/prevenção & controle , Vacina contra Caxumba/farmacologia , Vírus da Caxumba/classificação , Vírus da Caxumba/isolamento & purificação , Filogenia , Células Vero , Adulto Jovem
4.
Mediators Inflamm ; 2015: 804264, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26229239

RESUMO

Hypoxia activates the expression of proangiogenic and survival promoting factors as well as proinflammatory cytokines that support tissue inflammation. Hypoxia and inflammation are associated with tumor progression. The identification of the factors participating in the hypoxia associated inflammation is essential to develop strategies to control tumor hypoxia. The transcription factor ZNF395 was found to be overexpressed in various tumors including glioblastomas particularly in the network of a hypoxic response pointing to a functional role of ZNF395. On the other hand, ZNF395 was suggested to have tumor suppressor activities which may rely on its repression of proinflammatory factors. To address these conflictive observations, we investigated the role of ZNF395 in the expression of proinflammatory cytokines in the astrocytoma cell line U87-MG under hypoxia. We show that ZNF395 is a target gene of the hypoxia inducible factor HIF-1α. By gene expression analysis, RT-PCR and ELISA, we demonstrated that the siRNA-mediated suppression of ZNF395 impairs the hypoxic induction of IL-1ß, IL-6, IL-8, and LIF in U87-MG cells. At ambient oxygen concentrations, ZNF395 had no enhancing effect, indicating that this transcriptional activation by ZNF395 is restricted to hypoxic conditions. Our results suggest that ZNF395 contributes to hypoxia associated inflammation by superactivating proinflammatory cytokines.


Assuntos
Hipóxia Celular/fisiologia , Citocinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Hipóxia Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Fatores de Transcrição/genética
5.
Theor Biol Med Model ; 11: 51, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25471943

RESUMO

BACKGROUND: Papillomavirus binding factor (PBF) or zinc finger protein 395 is a transcription factor associated to a poor prognosis in patients with osteosarcoma, an aggressive bone cancer that predominantly affects adolescents. To investigate the role of the PBF protein in the osteosarcoma genesis, in this paper we present the bioinformatics analysis of physicochemical properties of PBF and its probable interactions with several key cellular targets. RESULTS: The physicochemical characteristics determined to PBF, disorder-promoting amino acids, flexibility, hydrophobicity, prediction of secondary and tertiary structures and probability to be crystallized, supported that this protein can be considered as an intrinsically disordered protein (IDP), with a zinc finger-like domain. The in silico analysis to find out PBF interactions with cellular factors, confirmed the experimentally demonstrated interaction of PBF with two key cellular proteins involved in regulation of cellular apoptosis, 14-3-3ß and Scythe/BAT3 proteins. Furthermore, other interactions were found with proteins like HDAC1 and TPR which are known to be deregulated in several cancers. Experimental confirmation of specific interactions will contribute to understand the osteosarcoma process and might lead to the identification of new targets for diagnosis and treatments. CONCLUSIONS: According to the in silico PBF analyses, this protein can be considered as an IDP capable to bind several key cellular factors, and these interactions might play an important role in the osteosarcoma process.


Assuntos
Neoplasias Ósseas/virologia , Proteínas Intrinsicamente Desordenadas/metabolismo , Osteossarcoma/virologia , Papillomaviridae/metabolismo , Dedos de Zinco , Sequência de Aminoácidos , Sequência de Bases , Neoplasias Ósseas/metabolismo , Simulação por Computador , Humanos , Dados de Sequência Molecular , Osteossarcoma/metabolismo , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
6.
PLoS One ; 8(10): e76876, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146939

RESUMO

Influenza A viruses are enveloped, segmented negative single-stranded RNA viruses, capable of causing severe human respiratory infections. Currently, only two types of drugs are used to treat influenza A infections, the M2 H(+) ion channel blockers (amantadine and rimantadine) and the neuraminidase inhibitors (NAI) (oseltamivir and zanamivir). Moreover, the emergence of drug-resistant influenza A virus strains has emphasized the need to develop new antiviral agents to complement or replace the existing drugs. Influenza A virus has on the surface a glycoprotein named hemagglutinin (HA) which due to its important role in the initial stage of infection: receptor binding and fusion activities of viral and endosomal membranes, is a potential target for new antiviral drugs. In this work we designed nine peptides using several bioinformatics tools. These peptides were derived from the HA1 and HA2 subunits of influenza A HA with the aim to inhibit influenza A virus infection. The peptides were synthetized and their antiviral activity was tested in vitro against several influenza A viral strains: Puerto Rico/916/34 (H1N1), (H1N1)pdm09, swine (H1N1) and avian (H5N2). We found these peptides were able to inhibit the influenza A viral strains tested, without showing any cytotoxic effect. By docking studies we found evidence that all the peptides were capable to bind to the viral HA, principally to important regions on the viral HA stalk, thus could prevent the HA conformational changes required to carry out its membranes fusion activity.


Assuntos
Antivirais/farmacologia , Biologia Computacional/métodos , Simulação por Computador , Desenho de Fármacos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/fisiologia , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Antivirais/química , Antivirais/toxicidade , Sítios de Ligação , Linhagem Celular , Sequência Conservada , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Simulação de Acoplamento Molecular , Peptídeos/química , Peptídeos/toxicidade , Conformação Proteica , Subunidades Proteicas , Replicação Viral/efeitos dos fármacos
7.
Bioinformation ; 8(11): 519-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22829722

RESUMO

Dengue virus (DENV 1-4) represents the major emerging arthropod-borne viral infection in the world. Currently, there is neither an available vaccine nor a specific treatment. Hence, there is a need of antiviral drugs for these viral infections; we describe the prediction of short interfering RNA (siRNA) as potential therapeutic agents against the four DENV serotypes. Our strategy was to carry out a series of multiple alignments using ClustalX program to find conserved sequences among the four DENV serotype genomes to obtain a consensus sequence for siRNAs design. A highly conserved sequence among the four DENV serotypes, located in the encoding sequence for NS4B and NS5 proteins was found. A total of 2,893 complete DENV genomes were downloaded from the NCBI, and after a depuration procedure to identify identical sequences, 220 complete DENV genomes were left. They were edited to select the NS4B and NS5 sequences, which were aligned to obtain a consensus sequence. Three different servers were used for siRNA design, and the resulting siRNAs were aligned to identify the most prevalent sequences. Three siRNAs were chosen, one targeted the genome region that codifies for NS4B protein and the other two; the region for NS5 protein. Predicted secondary structure for DENV genomes was used to demonstrate that the siRNAs were able to target the viral genome forming double stranded structures, necessary to activate the RNA silencing machinery.

8.
Mem Inst Oswaldo Cruz ; 103(2): 195-200, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18425273

RESUMO

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Infecções Respiratórias/virologia , Doença Aguda , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/isolamento & purificação , Técnicas de Tipagem Bacteriana , Criança , Enzimas de Restrição do DNA/análise , Feminino , Marcadores Genéticos , Genoma Viral , Humanos , Masculino , México/epidemiologia , Nasofaringe/virologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Estações do Ano
9.
Mem. Inst. Oswaldo Cruz ; 103(2): 195-200, Mar. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-480634

RESUMO

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23 percent, and only AdV C was detected.


Assuntos
Criança , Feminino , Humanos , Masculino , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Infecções Respiratórias/virologia , Doença Aguda , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/isolamento & purificação , Técnicas de Tipagem Bacteriana , Enzimas de Restrição do DNA/análise , Marcadores Genéticos , Genoma Viral , México/epidemiologia , Nasofaringe/virologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Estações do Ano
10.
Rev Latinoam Microbiol ; 47(3-4): 76-81, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17061531

RESUMO

A multitude of different polymerase chain reactions (PCRs) have been described for detection and typing of Herpes simplex virus (HSV). This paper compares two PCRs coupled to enzymatic restriction (PCR/RFLP) to detect and type HSV. A primers set was designed to amplify a HSV DNA fragment from UL30 and UL 15 genes. Typing was done by restriction of the UL30 and UL15 amplicons with Ava II and Hpa II enzymes, respectively. This strategy was tested with two reference strains (HSV-1 McIntyre, and HSV-2 G), and 47 clinical HSV isolates. Both PCRs produced the expected amplicons (a 492 bp UL30, and 305 bp UL15). The restriction of both amplicons clearly differentiated HSV- from HSV-2, and produced equal results. Thirty one (66%) of the isolates were identified as HSV-1, and the other 16 (34%), as HSV-2. Most of the HSV-1 isolates (27/31) were from orofacial and thoracic lesions; and also, one half of the HSV-2 isolates (8/16) were from the same anatomical regions. Our results showed that either of the two PCR/RFLP could be used to detect and type HSV. Furthermore, our results of the anatomical site of HSV-1 and HSV-2 infections are consistent with previous reports which have shown changes in the classical anatomical localization of herpesvirus infections.


Assuntos
Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Virologia/métodos , Animais , Chlorocebus aethiops , DNA Viral/isolamento & purificação , Herpes Genital/virologia , Herpesvirus Humano 1/classificação , Herpesvirus Humano 2/classificação , Humanos , Células Vero
11.
J Virol Methods ; 120(2): 161-5, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15288958

RESUMO

Ascorbate is an important antioxidant. However, in the presence of transition metals such as Cu(II) or Fe(III), it also has pro-oxidant capabilities. The effect of ascorbate-Cu(II) in the in vitro infection of herpes simplex virus type 2 (HSV-2) and its protecting effect in a murine model was investigated. HSV-2 was treated with different concentrations of ascorbate in the presence of Cu(II). A group of CF-1 mice were treated with the inactivated virus and other treated with maintenance medium containing only ascorbate-Cu(II). Weeks later, mice were challenged intranasally with infectious viruses. HSV-2 was completely inactivated by 2mM ascorbate plus 1mM Cu(II). Ascorbate or Cu(II) alone did not inactivate the virus. Compared with the control group, 60% of the immunized animals did not show any sign of encephalitis and survived the herpes virus infection, while a 7% survival rate was observed in the control group (P = 0.056). We concluded that the in vitro treatment of HSV-2 with ascorbate-Cu(II) is not only able to inactivate the virus, but also suggested that the viral particles induced a protective response against herpes encephalitis. This inactivation may provide an alternative method to develop new agents therapeutics.


Assuntos
Ácido Ascórbico/farmacologia , Cobre/farmacologia , Encefalite por Herpes Simples/prevenção & controle , Herpesvirus Humano 2/efeitos dos fármacos , Vacinas contra Herpesvirus/administração & dosagem , Inativação de Vírus , Animais , Ácido Ascórbico/administração & dosagem , Chlorocebus aethiops , Cobre/administração & dosagem , Encefalite por Herpes Simples/mortalidade , Encefalite por Herpes Simples/virologia , Herpes Simples/mortalidade , Herpes Simples/prevenção & controle , Herpes Simples/virologia , Herpesvirus Humano 2/crescimento & desenvolvimento , Vacinas contra Herpesvirus/imunologia , Imunização , Masculino , Camundongos , Células Vero
12.
Antiviral Res ; 56(3): 279-85, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12406511

RESUMO

Spirulina has been used in a variety of practical applications in biotechnology and medical sciences. This paper presents the antiviral activity found in a hot water extract (HWE) of a commercial preparation of Spirulina maxima, studied by a microplate inhibition assay, using several viruses. The HWE inhibited the infection for: herpes simplex virus type 2 (HSV-2), pseudorabies virus (PRV), human cytomegalovirus (HCMV), and HSV-1, and the 50% effective inhibition doses (ED(50)) were 0.069, 0.103, 0.142, and 0.333 mg/ml for each virus, respectively. For adenovirus the inhibition was less than 20%, and no inhibition was found for measles virus, subacute sclerosing panencephalitis virus (SSPE), vesicular stomatitis virus (VSV), poliovirus 1 and rotavirus SA-11, at concentrations of 2 mg/ml of the HWE. The highest antiviral activity was for HSV-2, with a selectivity index of 128. The antiviral activity was not due to a virucidal effect. Herpesvirus infection was inhibited at the initial events (adsorption and penetration) of the viral cycle. To initiate the isolation and identification of the compound that exhibits the antiviral activity of S. maxima, some extracts made by using several solvents with different polarity were evaluated by microplate inhibition assay using HSV-2. The highest antiviral activity was detected in the methanol-water 3:1, which suggests that the antiviral activity is probably due to highly polar compounds.


Assuntos
Antivirais/farmacologia , Cianobactérias/química , Herpesvirus Humano 2/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Chlorocebus aethiops , Efeito Citopatogênico Viral/efeitos dos fármacos , Herpesvirus Humano 2/fisiologia , Humanos , Células Vero , Ensaio de Placa Viral
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