Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
J Med Virol ; 95(11): e29205, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37933896

RESUMO

Norovirus is a major cause of acute diarrheal disease (ADD) outbreaks worldwide. In the present study, we investigated an ADD outbreak caused by norovirus in several municipalities of Santa Catarina state during the summer season, southern Brazil in 2023. As of the 10th epidemiological week of 2023, approximately 87 000 ADD cases were reported, with the capital, Florianópolis, recording the highest number of cases throughout the weeks. By using RT-qPCR and sequencing, we detected 10 different genotypes, from both genogroups (G) I and II. Some rare genotypes were also identified. Additionally, rotavirus and human adenovirus were sporadically detected among the ADD cases. Several features of the outbreak suggest that sewage-contaminated water could played a role in the surge of ADD cases. Storm events in Santa Catarina state that preceded the outbreak likely increased the discharge of contaminated wastewater and stormwater into water bodies, such as rivers and beaches during a high touristic season in the state. Climate change-induced extreme weather events, including intensified rainfall and frequent floods, can disturb healthcare and sanitation systems. Implementing public policies for effective sanitation, particularly during peak times, is crucial to maintain environmental equilibrium and counter marine pollution.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Norovirus/genética , Brasil/epidemiologia , Surtos de Doenças , Genótipo , Água , Infecções por Caliciviridae/epidemiologia , Fezes
2.
An. bras. dermatol ; 98(2): 198-201, March.-Apr. 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1429665

RESUMO

Abstract Background: Human Polyomaviruses such as MCPyV and HPyV6 are frequently found as part of healthy skin microbiota and have been associated with Merkel cell carcinoma (MCC), pruritic and dyskeratotic dermatoses, respectively. Their presence in other types of skin conditions varies greatly depending on lesion type and population. Objectives: To analyse comparatively the presence of MCPyV and HPyV6 in nonmelanoma skin cancers and healthy skin. Methods: The authors utilized qPCR techniques to quantify these pathogens in NMSC, premalignant diseases, and healthy skin of 87 patients. Results: MCPyV was detected in over 40% of samples, while HPyV6 was in 9.6%. MCPyV load was higher in squamous cell carcinomas (SCC) compared to basal cell carcinomas (BCC) (p = 0.016) and HPyV6 showed a higher percentage of infected cells in areas of low solar exposure as well as normal skin (p = 0.012). A fair agreement (kappa = 0.301) was found between MCPyV detection in lesions and their respective perilesional skin, indicating a random process of local dissemination of the virus. Study limitations: The lack of a larger sampling of different lesion types and protein expression analyses limits the correlation findings. Conclusions: This is the first report of HPyV6 detection in the healthy skin of a Brazilian population, but the role of both polyomaviruses in NMSC has yet to be demonstrated.

3.
An Bras Dermatol ; 98(2): 198-201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36635157

RESUMO

BACKGROUND: Human Polyomaviruses such as MCPyV and HPyV6 are frequently found as part of healthy skin microbiota and have been associated with Merkel cell carcinoma (MCC), pruritic and dyskeratotic dermatoses, respectively. Their presence in other types of skin conditions varies greatly depending on lesion type and population. OBJECTIVE: To analyse comparatively the presence of MCPyV and HPyV6 in nonmelanoma skin cancers and healthy skin. METHODS: The authors utilized qPCR techniques to quantify these pathogens in NMSC, premalignant diseases, and healthy skin of 87 patients. RESULTS: MCPyV was detected in over 40% of samples, while HPyV6 was in 9.6%. MCPyV load was higher in squamous cell carcinomas (SCC) compared to basal cell carcinomas (BCC) (p=0.016) and HPyV6 showed a higher percentage of infected cells in areas of low solar exposure as well as normal skin (p=0.012). A fair agreement (kappa=0.301) was found between MCPyV detection in lesions and their respective perilesional skin, indicating a random process of local dissemination of the virus. STUDY LIMITATIONS: The lack of a larger sampling of different lesion types and protein expression analyses limits the correlation findings. CONCLUSION: This is the first report of HPyV6 detection in the healthy skin of a Brazilian population, but the role of both polyomaviruses in NMSC has yet to be demonstrated.


Assuntos
Carcinoma Basocelular , Carcinoma de Célula de Merkel , Poliomavírus das Células de Merkel , Polyomavirus , Neoplasias Cutâneas , Humanos , Carcinoma de Célula de Merkel/patologia , DNA Viral/análise , DNA Viral/metabolismo , Poliomavírus das Células de Merkel/genética , Poliomavírus das Células de Merkel/metabolismo , Polyomavirus/genética , Neoplasias Cutâneas/patologia
4.
Int J Immunogenet ; 49(6): 379-383, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36193010

RESUMO

We investigated the effects of TNF-α, IFN-γ, IL-10 polymorphisms on viral infections (CMV, BKPyV, HHV-6, EBV) after renal transplantation. IFN-γ+874 A > T (lower IFN production) was associated with CMV disease (p = .039) in patients under mycophenolate-based therapy and graft failure (p = .025). This study underscores the role of IFN-γ+874 SNP in CMV infection.


Assuntos
Infecções por Citomegalovirus , Transplante de Rim , Humanos , Citomegalovirus/genética , Transplante de Rim/efeitos adversos , Citocinas , Infecções por Citomegalovirus/genética , Interferon gama/genética
5.
Front Pediatr ; 10: 934648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923786

RESUMO

Introduction: The coronavirus disease-2019 (COVID-19) clinical manifestations in children and adolescents are diverse, despite the respiratory condition being the main presentation. Factors such as comorbidities and other respiratory infections may play a role in the initial presentation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aims to describe the epidemiological aspects, clinical, and laboratory manifestations of pediatric patients admitted to a tertiary pediatric hospital in Rio de Janeiro, diagnosed with COVID-19, and compare these with other viral conditions during the first year of the SARS-CoV-2 pandemic. Methods: All patients under 18 years of age that were admitted with upper airway infection were enrolled and followed up for 30 days. The main dependent variable was the laboratorial diagnosis of SARS-CoV-2, and independent variables were studied through logistic regression. Results: A total of 533 patients were recruited, and 105 had confirmed SARS-CoV-2 infection. Detection of other viruses occurred in 34% of 264 tested participants. Six patients died (two in SARS-CoV-2 infected group). The variables independently associated with COVID-19 were older age (OR = 1.1, 95% CI = 1.0-1.1), lower leukocytes count at entry (OR = 0.9, 95% CI = 0.8-0.9), and contact with suspected case (OR = 1.6, 95% CI = 1.0-2.6). Patients with COVID-19 presented higher odds to be admitted in an intensive care unit (OR = 1.99, 95% CI = 1.08-3.66). Conclusions: Even during the SARS-CoV-2 pandemic, several other respiratory viruses were present in admitted pediatric patients. Variables associated with COVID-19 infection were older age, lower leukocytes count at entry, and a domiciliary suspect contact. Although patients with COVID-19 were more frequently admitted to ICU, we did not observe higher mortality in this group.

6.
J Cent Nerv Syst Dis ; 14: 11795735221102740, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35633836

RESUMO

Neurological manifestations of COVID-19 may affect both central and peripheral nervous systems. Unlike in adults, in whom majority of severe cases derive from respiratory complications, neurological involvement is one of the main causes of severe COVID-19 in children. This study aimed to detect viral respiratory pathogens, mainly SARS-CoV-2, in nasopharynx and cerebrospinal fluid samples utilizing qRT-PCR (TaqMan) in a pediatric population in Brazil. We evaluated four children with neurological symptoms and laboratory-confirmed SARS-CoV-2 infection: three presenting with meningoencephalitis and one presenting with Guillain-Barré syndrome. All four patients had mild respiratory symptoms. SARS-CoV-2 RNA was identified in two cerebrospinal fluid samples. SARS-CoV-2 involvement should be considered for differential diagnosis in pediatric cases presenting neurological alterations even if symptoms such as headache, anosmia, or dizziness are absent.

7.
PLoS One ; 17(1): e0262170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35051202

RESUMO

The SARS-CoV-2 responsible for the ongoing COVID pandemic reveals particular evolutionary dynamics and an extensive polymorphism, mainly in Spike gene. Monitoring the S gene mutations is crucial for successful controlling measures and detecting variants that can evade vaccine immunity. Even after the costs reduction resulting from the pandemic, the new generation sequencing methodologies remain unavailable to a large number of scientific groups. Therefore, to support the urgent surveillance of SARS-CoV-2 S gene, this work describes a new feasible protocol for complete nucleotide sequencing of the S gene using the Sanger technique. Such a methodology could be easily adopted by any laboratory with experience in sequencing, adding to effective surveillance of SARS-CoV-2 spreading and evolution.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/epidemiologia , Genes Virais , Pandemias/prevenção & controle , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , Análise de Sequência de RNA/métodos , Glicoproteína da Espícula de Coronavírus/genética , Sequência de Bases , Brasil/epidemiologia , COVID-19/virologia , Testes Diagnósticos de Rotina/métodos , Eletroforese em Gel de Ágar/métodos , Monitoramento Epidemiológico , Humanos , Mutação , RNA Viral/genética , RNA Viral/isolamento & purificação
9.
Pathogens ; 9(8)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785066

RESUMO

Human bocavirus (HBoV) is an emerging virus and has been detected worldwide, especially in pediatric patients with respiratory and gastrointestinal infection. In this study, we describe HBoV prevalence, genotypes circulation and DNA shedding, in stool samples from children up to two years of age in Brazil. During 2016 and 2017, 886 acute gastroenteritis (AGE) stool samples from ten Brazilian states were analyzed by TaqMan®-based qPCR, to detect and quantify HBoV. Positive samples were genotyped by sequencing the VP1/2 overlap region, followed by phylogenetic analysis and co-infections were accessed by screening other gastroenteric viruses. HBoV was detected in 12.4% (n = 110) of samples, with viral load ranging from 1.6 × 102 to 1.2 × 109 genome copies per gram of stool. From these, co-infections were found in 79.1%, and a statistically lower HBoV viral load was found compared to viral loads of rotavirus, norovirus and adenovirus in double infected patients (p < 0.05). No significant differences were found between HBoV viral load in single or co-infections, age groups or genotypes. Phylogenetic analysis identified the circulation of HBoV-1 in 38%, HBoV-2 in 40% and HBoV-3 in 22%. Continuous HBoV monitoring is needed to clarify its role in diarrhea disease, especially in the absence of classic gastroenteric viruses.

11.
Arq Neuropsiquiatr ; 78(3): 163-168, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32215459

RESUMO

Herpes simplex virus (HSV) is a cause of a severe disease of the central nervous system (CNS) in humans. The demonstration of specific antibodies in the cerebrospinal fluid (CSF) may contribute to the retrospective neurological diagnosis. However, the commercial immunological tests for HSV infection are for use in serum samples. OBJECTIVE: The aim of the present study was to adapt a commercial kit anti-HSV IgG used for serum samples to be performed with a CSF sample. METHODS: Forty CSF specimens from 38 patients with suspected CNS HSV infection were serially diluted for detecting anti-HSV IgG by enzyme immunoassay (EIA). The same samples were also analyzed with the polymerase chain reaction (PCR). RESULTS: The sensitivity of EIA test for HSV was 5% (dilution 1:40) and 65% (dilution 1:2) in CSF, and HSV DNA PCR was 15%. The combined analysis of EIA (dilution 1:2) and PCR increased the sensitivity up to 72.5%. The inflammatory CSF was associated with positive HSV PCR. CONCLUSIONS: We demonstrated the importance to adapt serological anti-HSV IgG EIA test for CSF assays to increase the accuracy of the analysis, considering the low concentration of specific antibodies in CSF.


Assuntos
Anticorpos Antivirais/líquido cefalorraquidiano , Líquido Cefalorraquidiano/virologia , Herpes Simples/diagnóstico , Herpes Simples/virologia , Simplexvirus/isolamento & purificação , Adulto , DNA Viral/genética , DNA Polimerase Dirigida por DNA/genética , Exodesoxirribonucleases , Feminino , Herpes Simples/líquido cefalorraquidiano , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Simplexvirus/genética , Proteínas Virais
12.
Arq. neuropsiquiatr ; 78(3): 163-168, Mar. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1098075

RESUMO

Abstract Herpes simplex virus (HSV) is a cause of a severe disease of the central nervous system (CNS) in humans. The demonstration of specific antibodies in the cerebrospinal fluid (CSF) may contribute to the retrospective neurological diagnosis. However, the commercial immunological tests for HSV infection are for use in serum samples. Objective: The aim of the present study was to adapt a commercial kit anti-HSV IgG used for serum samples to be performed with a CSF sample. Methods: Forty CSF specimens from 38 patients with suspected CNS HSV infection were serially diluted for detecting anti-HSV IgG by enzyme immunoassay (EIA). The same samples were also analyzed with the polymerase chain reaction (PCR). Results: The sensitivity of EIA test for HSV was 5% (dilution 1:40) and 65% (dilution 1:2) in CSF, and HSV DNA PCR was 15%. The combined analysis of EIA (dilution 1:2) and PCR increased the sensitivity up to 72.5%. The inflammatory CSF was associated with positive HSV PCR. Conclusions: We demonstrated the importance to adapt serological anti-HSV IgG EIA test for CSF assays to increase the accuracy of the analysis, considering the low concentration of specific antibodies in CSF.


Resumo O vírus herpes simples (HSV) é um dos agentes causadores de uma doença grave no sistema nervoso central (SNC) em humanos. A detecção de anticorpos específicos no líquido cefalorraquidiano (LCR) pode contribuir para o diagnóstico neurológico retrospectivo. Entretanto, os testes imunológicos comerciais são para uso em amostras de soro. Objetivo: Adaptar um kit comercial sorológico anti-HSV IgG para ser utilizado no de LCR. Metodos: Quarenta amostras de LCR de 38 pacientes com suspeita de infecção por HSV no SNC foram diluídas pesquisa de anticorpos anti-HSV IgG pelo método imunoenzimático (EIA). Além disso, as mesmas amostras também foram analisadas por reação em cadeia da polimerase (PCR). Resultados: A sensibilidade do teste EIA para o HSV consistiu em 5% (diluição 1:40) e 65% (diluição 1:2) no LCR, e o PCR do DNA do HSV, 15%. A análise combinada de EIA (diluição 1:2) e PCR aumentou a sensibilidade para 72,5%. Houve associação entre presença do LCR inflamatório e PCR positiva para HSV. Conclusões: Demonstramos a importância na adaptação previa do teste sorológico anti-HSV IgG EIA para ensaios do no LCR, a fim de aumentar a acuracia da análise, considerando a baixa concentração de anticorpos específicos no LCR.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Líquido Cefalorraquidiano/virologia , Simplexvirus/isolamento & purificação , Herpes Simples/diagnóstico , Herpes Simples/virologia , Anticorpos Antivirais/líquido cefalorraquidiano , Proteínas Virais , DNA Viral/genética , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Simplexvirus/genética , DNA Polimerase Dirigida por DNA/genética , Exodesoxirribonucleases , Herpes Simples/líquido cefalorraquidiano , Sistema Nervoso
13.
J Med Virol ; 92(1): 107-112, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31463932

RESUMO

The increased risk for opportunistic infections after a renal transplant requires monitoring of viral infections to avoid future complications. Our goal was to investigate the impact and factors associated with Epstein-Barr virus (EBV), human cytomegalovirus (HCMV) and human herpesvirus type 6 (HHV-6) viremia in renal transplant recipients. Whole blood samples were collected monthly from 82 patients during the first semester and then quarterly up to 1 year after transplantation. EBV, HCMV, and HHV-6 were detected and quantified by TaqMan real-time polymerase chain reaction. The results showed that EBV and HCMV viremia were detected in 32 patients (39% each), while HHV-6 viremia in only 3 patients (3.7%). EBV was significantly associated with age (P = .050), thymoglobuline induction (P = .019), mTOR inhibitor-based therapy (P = .003), and female gender (P = .044). HCMV was significantly associated with basiliximab induction (P = .015), mycophenolate mofetil (MMF)-based therapy (P = .003) and allograft acute rejection (P = .033). Moreover, HCMV-disease was correlated with MMF-based therapy (P = .021) and female gender (P = .003). In conclusion, EBV and HCMV viremia were associated with different immunosuppressive induction and maintenance strategies. Additionally, higher HCMV viremia (> 10 4 copies/mL) was related to acute allograft rejection.


Assuntos
DNA Viral/sangue , Infecções por Herpesviridae/sangue , Transplante de Rim/efeitos adversos , Transplantados , Viremia/etiologia , Adulto , Citomegalovirus/genética , Infecções por Citomegalovirus/sangue , Infecções por Vírus Epstein-Barr/sangue , Feminino , Herpesviridae/patogenicidade , Infecções por Herpesviridae/etiologia , Herpesvirus Humano 4/genética , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Carga Viral
14.
Eur J Clin Microbiol Infect Dis ; 38(6): 1129-1133, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30788731

RESUMO

Non-melanoma skin cancers (NMSC) share similar risk factors with other virus-related cancers, despite the lack of proved causal association between viral infection and NMSC development. We investigated the presence of Merkel cell polyomavirus (MCPyV), Epstein-Barr virus (EBV), and human papillomavirus (HPV) DNA in 83 NMSC fresh-frozen and 16 non-cancerous skin biopsies and evaluated viral infection according to demographical data, histopathological diagnosis, and ultraviolet exposure. Our results showed that 75% of NMSC biopsies were positive for at least one out of three viruses, whereas only 38% of non-cancerous skin biopsies were positive (p = 0.02). Notably, HPV detection was frequent in NMSC (43%) and nearly absent (one sample, 6.7%) in non-cancerous biopsies (p = 0.007). MCPyV was associated with sites of higher exposure to ultraviolet radiation (p = 0.010), while EBV was associated with a compromised immune system (p = 0.032). Our study showed that HPV was strongly associated with NMSC while EBV and MCPyV with other risk factors. Though further studies are required to elucidate the role of viral infection in NMSC development and management, this study supports the possible role of oncogenic viruses in skin cancers, especially HPV.


Assuntos
Papillomaviridae/isolamento & purificação , Neoplasias Cutâneas/virologia , Infecções Tumorais por Vírus/virologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Masculino , Poliomavírus das Células de Merkel/isolamento & purificação , Pessoa de Meia-Idade , Fatores de Risco , Neoplasias Cutâneas/patologia , Infecções Tumorais por Vírus/patologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-30231168

RESUMO

BKV and JCV belong to the Polyomaviridae family and are opportunistic agents associated with complications in immunocompromised individuals. Although a single screening assay for both viruses would be convenient, the diversity of BKV and JCV serotypes and genotypes is a methodological challenge. In this paper, we developed a PCR method able to detect and segregate BKV and JCV, despite these genetic discrepancies. A duplex semi-nested PCR (duplex snPCR) was designed to target a conserved region (639nt-1516nt) within the VP2 gene. In the first PCR, a primer set common to all BKV and JCV serotypes/ genotypes was used, followed by a semi-nested PCR with internal primers for BKV and JCV segregation. The limit of detection of the duplex snPCR was as low as 10 copies of BKV or JCV plasmids/µL. Specific products were observed when JCV and BKV plasmids were mixed in the same reaction. In field sample testing, the duplex snPCR detected and distinguished both viruses in different biological samples. Results were confirmed by Sanger's sequencing. The geographical complexity of BKV and JCV serotypes and genotypes imposes limits to a simple and universal method that could detect each virus. However, we describe here a sensitive and reliable PCR technique for BKV and JCV diagnosis that overcomes these limitations and could be universally applied.


Assuntos
Vírus BK/isolamento & purificação , DNA Viral/genética , Vírus JC/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Vírus BK/classificação , Vírus BK/genética , Genótipo , Humanos , Vírus JC/classificação , Vírus JC/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-28793012

RESUMO

Pemphigus foliaceus (PF) is an autoimmune disease characterized by blistering of the skin. Infections caused by members of the herpesviridae family have been suggested as a possible triggering factor for pemphigus vulgaris (PV), but not for PF. The present study aimed to investigate the presence of Human herpesvirus (types 1, 2, 3) in corticosteroid refractory skin lesions from a patient with PF, by a Polymerase chain reaction (PCR) assay. The sample collected from cutaneous blisters has tested positive for herpes simplex virus type 1 (HSV1) after sequence analysis of the amplified viral genomic segment. The study concluded that when PF patients present corticosteroid or immunosuppressants refractory lesions, herpetic infection should be considered.


Assuntos
Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/diagnóstico , Pênfigo/virologia , Pele/virologia , Herpesviridae/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Pênfigo/complicações , Recidiva
17.
Rev Inst Med Trop Sao Paulo ; 58: 58, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27410918

RESUMO

The aim of this study was to investigate the association of EBV and HPV with gingivitis and/or periodontitis according to the immunologic status. To this end, 74 oral biopsies from transplanted and non-transplanted individuals with the abovementioned oral manifestations were submitted to a screening by PCR for both viruses. According to the results, EBV was strongly associated with gingivitis and/or periodontitis in transplanted individuals (p = 0.011) but not HPV (p = 0.766). EBV-HPV co-detections did not enhance the presence of tissue injury as well. Although a causal relationship was not investigated in this study, the higher frequency of these two oncoviruses in lesion tissues must be investigated in follow-up studies, especially among immunocompromised individuals.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Gengivite/virologia , Transplante de Rim , Infecções por Papillomavirus/diagnóstico , Periodontite/virologia , Estudos de Casos e Controles , DNA Viral/genética , Gengivite/diagnóstico , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Periodontite/diagnóstico , Reação em Cadeia da Polimerase
18.
Virus Res ; 221: 1-7, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27173789

RESUMO

Our understanding of the phylogenetic and structural characteristics of the Merkel Cell Polyomavirus (MCPyV) is increasing but still scarce, especially in samples originating from South America. In order to investigate the properties of MCPyV circulating in the continent in more detail, MCPyV Viral Protein 1 (VP1) sequences from five basal cell carcinoma (BCC) and four saliva samples from Brazilian individuals were evaluated from the phylogenetic and structural standpoint, along with all complete MCPyV VP1 sequences available at Genbank database so far. The VP1 phylogenetic analysis confirmed the previously reported pattern of geographic distribution of MCPyV genotypes and the complexity of the South-American clade. The nine Brazilian samples were equally distributed in the South-American (3 saliva samples); North American/European (2 BCC and 1 saliva sample); and in the African clades (3 BCC). The classification of mutations according to the functional regions of VP1 protein revealed a differentiated pattern for South-American sequences, with higher number of mutations on the neutralizing epitope loops and lower on the region of C-terminus, responsible for capsid formation, when compared to other continents. In conclusion, the phylogenetic analysis showed that the distribution of Brazilian VP1 sequences agrees with the ethnic composition of the country, indicating that VP1 can be successfully used for MCPyV phylogenetic studies. Finally, the structural analysis suggests that some mutations could have impact on the protein folding, membrane binding or antibody escape, and therefore they should be further studied.


Assuntos
Proteínas do Capsídeo/genética , Variação Genética , Poliomavírus das Células de Merkel/classificação , Poliomavírus das Células de Merkel/isolamento & purificação , Filogenia , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Brasil , Carcinoma Basocelular/virologia , Epitopos de Linfócito B/genética , Poliomavírus das Células de Merkel/genética , Mutação de Sentido Incorreto
19.
J Clin Virol ; 73: 77-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26580407

RESUMO

BACKGROUND: Lower respiratory tract viral infection is an important cause of morbidity and mortality in children worldwide. Among viral etiological agents the human Adenovirus (AdV) has been associated to mild or severe respiratory tract infection. OBJECTIVE: To detect the presence of human Adenovirus (AdV) in children with acute bronchiolitis or recurrent wheezing, describing their clinical features and determining Adenovirus species and AdV association to Respiratory Syncytial Virus (RSV), Human Metapneumovirus (MPV) and Parainfluenza virus (PIV). STUDY DESIGN: A total of 155 children bellow 48 months of age with acute bronchiolitis or recurrent wheezing were investigated for the presence of AdV, RSV, MPV and PIV in nasopharyngeal aspirate, by real-time PCR method. RESULTS: AdV, predominantly of species C, has been detected as the unique pathogen (AdVi) or in association to other pathogens (AdVa.), in 39/155 samples. Crackles were more frequent in children with AdV. RSVi was detected predominantly in children with acute bronchiolitis while AdVi and AdVa were detected more frequently in patients with recurrent wheezing. CONCLUSION: A small outbreak of AdV species C was observed in 2012 and 2013. AdV was detected more frequently in children with recurrent wheezing while RSVi was more frequent in infants with acute bronchiolitis.


Assuntos
Infecções por Adenovirus Humanos/diagnóstico , Adenovírus Humanos/classificação , Adenovírus Humanos/isolamento & purificação , Bronquiolite Viral/virologia , Infecções Respiratórias/virologia , Adenovírus Humanos/genética , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Humanos , Lactente , Recém-Nascido , Nasofaringe/virologia , Filogenia , Recidiva , Sons Respiratórios
20.
J Med Virol ; 87(8): 1418-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25778462

RESUMO

Polyomavirus BK (BKPyV) T-antigens (large and small tumor antigens, or Lt-ag and st-ag, respectively), control key aspects of viral replication and are able to regulate cell cycle, promoting cell proliferation. However, the structural effects of genetic mutations on T-antigens are poorly investigated. In this study, 214 sequences of T-antigens from individuals with different BKPyV infections (16 renal transplant with nephropathy; 78 asymptomatic renal transplant; 24 hematopoietic stem cell transplant with hemorrhagic cystitis; 96 healthy non-transplant), were analyzed from the genetic and structural standpoints. We found a high concentration of non-synonymous mutations at inter-domains and hexamerization regions of both proteins, being five of them under positive selection in the Lt-ag but none in the st-ag. The in silico analysis indicated that two mutations, located at positions 164 in the st-ag and 592 in the Lt-ag, would significantly affect the interaction with PP2A and p53 cell targets, respectively, although they were not associated to a specific clinical status. No mutations were detected on the J-domains or at the ATPase motif. In sum, the profile of the mutations found seem not to be associated to increased morbidity. This is the first work to analyze structural modifications on T-antigens in different BKPyV infections, and managed to map conserved and variable regions of the T-antigens, which will be helpful for the study of new antiviral drugs.


Assuntos
Antígenos Virais de Tumores/genética , Vírus BK/classificação , Vírus BK/genética , Variação Genética , Mutação de Sentido Incorreto , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Vírus BK/isolamento & purificação , DNA Viral/química , DNA Viral/genética , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Estrutura Terciária de Proteína , Análise de Sequência de DNA
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA