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1.
Trop Med Int Health ; 29(3): 173-191, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38263345

RESUMEN

OBJECTIVE: Severe dengue is a significant health problem in Latin America, with children being the most affected. Understanding risk factors for severe dengue is crucial for enhancing patient care. Therefore, this study aims to systematically review the literature to identify the risk factors associated with severe dengue in Latin America through systematic review and meta-analysis. METHODS: PubMed, SciELO, LILACS and EMBASE databases were used to search for eligible scientific articles for the review. The outcomes considered were symptoms of severe dengue, hospitalisation and death. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the quality of the studies. Data analysis was performed using STATA v 13.0 software. The degree of heterogeneity between studies was quantified using the I2 measure, and statistically significant results were defined as those with p values <0.05. RESULTS: Of the 1876 articles screened, 47 articles were included in the systematic review and 45 articles were analysed through meta-analysis. Identified risk factors associated with severe dengue included secondary dengue infection, female sex, white or Caucasian ethnicity and specific signs and symptoms such as headache, myalgia and/or arthralgia, vomiting/nausea, abdominal pain or tenderness, diarrhoea, prostration, lethargy, fatigue or similar. For the death outcome, respiratory symptoms and age <18 years were identified as risk factors. On the other hand, in women, the diagnosis of positive tourniquet test, platelet count <100,000 per µL and symptoms of capillary fragility were associated with a lower probability of death. These data highlight the importance of early screening of patients, to identify possible haemorrhagic signs and reduce deaths from dengue. This study has limitations, including possible publication bias, heterogeneity of results and study design biases. CONCLUSION: These findings are significant for shaping strategies, management approaches and identifying high-risk groups, which will help establish future guidelines.


Asunto(s)
Dengue Grave , Niño , Humanos , Femenino , Adolescente , Dengue Grave/epidemiología , América Latina/epidemiología , Factores de Riesgo , Hospitalización
2.
Front Microbiol ; 14: 1221682, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601355

RESUMEN

Visceral leishmaniasis is an opportunistic disease in HIV-1 infected individuals, unrecognized as a determining factor for AIDS diagnosis. The growing geographical overlap of HIV-1 and Leishmania infections is an emerging challenge worldwide, as co-infection increases morbidity and mortality for both infections. Here, we determined the prevalence of people living with HIV (PWH) with a previous or ongoing infection by Leishmania infantum and investigated the virological and immunological factors associated with co-infection. We adopted a two-stage cross-sectional cohort (CSC) design (CSC-I, n = 5,346 and CSC-II, n = 317) of treatment-naïve HIV-1-infected individuals in Bahia, Brazil. In CSC-I, samples collected between 1998 and 2013 were used for serological screening for leishmaniasis by an in-house Enzyme-Linked Immunosorbent Assay (ELISA) with SLA (Soluble Leishmania infantum Antigen), resulting in a prevalence of previous or ongoing infection of 16.27%. Next, 317 PWH were prospectively recruited from July 2014 to December 2015 with the collection of sociodemographic and clinical data. Serological validation by two different immunoassays confirmed a prevalence of 15.46 and 8.20% by anti-SLA, and anti-HSP70 serology, respectively, whereas 4.73% were double-positive (DP). Stratification of these 317 individuals in DP and double-negative (DN) revealed a significant reduction of CD4+ counts and CD4+/CD8+ ratios and a tendency of increased viral load in the DP group, as compared to DN. No statistical differences in HIV-1 subtype distribution were observed between the two groups. However, we found a significant increase of CXCL10 (p = 0.0076) and a tendency of increased CXCL9 (p = 0.061) in individuals with DP serology, demonstrating intensified immune activation in this group. These findings were corroborated at the transcriptome level in independent Leishmania- and HIV-1-infected cohorts (Swiss HIV Cohort and Piaui Northeast Brazil Cohort), indicating that CXCL10 transcripts are shared by the IFN-dominated immune activation gene signatures of both pathogens and positively correlated to viral load in untreated PWH. This study demonstrated a high prevalence of PWH with L. infantum seropositivity in Bahia, Brazil, linked to IFN-mediated immune activation and a significant decrease in CD4+ levels. Our results highlight the urgent need to increase awareness and define public health strategies for the management and prevention of HIV-1 and L. infantum co-infection.

3.
Viruses ; 15(8)2023 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-37631993

RESUMEN

(1) Background: The HIV subtype D is generally associated with a faster decline in CD4+ T cell counts, a higher viral load, and a faster progression to AIDS. However, it is still poorly characterized in Brazil. In this study, we used genomics and epidemiological data to investigate the transmission dynamics of HIV subtype D in the state of Bahia, Northeast Brazil. (2) Methods: To achieve this goal, we obtained four novel HIV-1 subtype D partial pol genome sequences using the Sanger method. To understand the emergence of this novel subtype in the state of Bahia, we used phylodynamic analysis on a dataset comprising 3704 pol genome sequences downloaded from the Los Alamos database. (3) Results: Our analysis revealed three branching patterns, indicating multiple introductions of the HIV-1 subtype D in Brazil from the late 1980s to the late 2000s and a single introduction event in the state of Bahia. Our data further suggest that these introductions most likely originated from European, Eastern African, Western African, and Southern African countries. (4) Conclusion: Understanding the distribution of HIV-1 viral strains and their temporal dynamics is crucial for monitoring the real-time evolution of circulating subtypes and recombinant forms, as well as for designing novel diagnostic and vaccination strategies. We advocate for a shift to active surveillance, to ensure adequate preparedness for future epidemics mediated by emerging viral strains.


Asunto(s)
Seropositividad para VIH , VIH-1 , Humanos , Brasil/epidemiología , VIH-1/genética , Genómica , Bases de Datos Factuales
4.
Epidemiol Serv Saude ; 32(2): e2022614, 2023.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-37610938

RESUMEN

MAIN RESULTS: Technology transfer can take place at large events, as long as safety protocols are strictly enforced. It is important to disseminate, at these events, the concepts of the Responsible Research and Innovation (RRI). Implications for services: Face-to-face training course is fundamental for training public health professionals. Technology transfer between research institutions and health services results in updating and improving health system performance. PERSPECTIVES: Based on the success of the reported technology transfer, a new module will be incorporated into the next edition of VEME (Panama 2022), entitled Virus Evolution to Public Health Policy Makers. The objective of this report was to describe the first face-to-face course aimed at training public health professionals in performing real-time genomic surveillance during the pandemic period. Experience report on a theoretical-practical course focusing on genomic research and surveillance, including mobile sequencing technologies, bioinformatics, phylogenetics and epidemiological modeling. There were 162 participants in the event and it was the first major face-to-face training course conducted during the COVID-19 epidemic in Brazil. No cases of SARS-CoV-2 infection was detected among the participants at the end of the event, suggesting the safety and effectiveness of all safety measures adopted. The results of this experience suggest that it is possible to conduct professional training safely during pandemics, as long as all safety protocols are followed.


Asunto(s)
COVID-19 , Educación en Salud Pública Profesional , Transferencia de Tecnología , Humanos , Brasil/epidemiología , COVID-19/epidemiología , Pandemias , SARS-CoV-2 , Educación en Salud Pública Profesional/métodos
5.
J Med Virol ; 95(8): e29012, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37548148

RESUMEN

This comprehensive review focuses on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its impact as the cause of the COVID-19 pandemic. Its objective is to provide a cohesive overview of the epidemic history and evolutionary aspects of the virus, with a particular emphasis on its emergence, global spread, and implications for public health. The review delves into the timelines and key milestones of SARS-CoV-2's epidemiological progression, shedding light on the challenges encountered during early containment efforts and subsequent waves of transmission. Understanding the evolutionary dynamics of the virus is crucial in monitoring its potential for adaptation and future outbreaks. Genetic characterization of SARS-CoV-2 is discussed, with a focus on the emergence of new variants and their implications for transmissibility, severity, and immune evasion. The review highlights the important role of genomic surveillance in tracking viral mutations linked to establishing public health interventions. By analyzing the origins, global spread, and genetic evolution of SARS-CoV-2, valuable insights can be gained for the development of effective control measures, improvement of pandemic preparedness, and addressing future emerging infectious diseases of international concern.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Pandemias/prevención & control , Salud Pública , Brotes de Enfermedades
6.
Viruses ; 15(6)2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37376536

RESUMEN

The Americas, particularly Brazil, were greatly impacted by the widespread Zika virus (ZIKV) outbreak in 2015 and 2016. Efforts were made to implement genomic surveillance of ZIKV as part of the public health responses. The accuracy of spatiotemporal reconstructions of the epidemic spread relies on the unbiased sampling of the transmission process. In the early stages of the outbreak, we recruited patients exhibiting clinical symptoms of arbovirus-like infection from Salvador and Campo Formoso, Bahia, in Northeast Brazil. Between May 2015 and June 2016, we identified 21 cases of acute ZIKV infection and subsequently recovered 14 near full-length sequences using the amplicon tiling multiplex approach with nanopore sequencing. We performed a time-calibrated discrete phylogeographic analysis to trace the spread and migration history of the ZIKV. Our phylogenetic analysis supports a consistent relationship between ZIKV migration from Northeast to Southeast Brazil and its subsequent dissemination beyond Brazil. Additionally, our analysis provides insights into the migration of ZIKV from Brazil to Haiti and the role Brazil played in the spread of ZIKV to other countries, such as Singapore, the USA, and the Dominican Republic. The data generated by this study enhances our understanding of ZIKV dynamics and supports the existing knowledge, which can aid in future surveillance efforts against the virus.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Humanos , Virus Zika/genética , Brasil/epidemiología , Filogenia , Américas/epidemiología
7.
Front Immunol ; 14: 1073779, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36860854

RESUMEN

Introduction: The Human T-lymphotropic virus type 1 (HTLV-1) was the first described human retrovirus. It is currently estimated that around 5 to 10 million people worldwide are infected with this virus. Despite its high prevalence, there is still no preventive vaccine against the HTLV-1 infection. It is known that vaccine development and large-scale immunization play an important role in global public health. To understand the advances in this field we performed a systematic review regarding the current progress in the development of a preventive vaccine against the HTLV-1 infection. Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA®) guidelines and was registered at the International Prospective Register of Systematic Reviews (PROSPERO). The search for articles was performed in PubMed, Lilacs, Embase and SciELO databases. From the 2,485 articles identified, 25 were selected according to the inclusion and exclusion criteria. Results: The analysis of these articles indicated that potential vaccine designs in development are available, although there is still a paucity of studies in the human clinical trial phase. Discussion: Although HTLV-1 was discovered almost 40 years ago, it remains a great challenge and a worldwide neglected threat. The scarcity of funding contributes decisively to the inconclusiveness of the vaccine development. The data summarized here intends to highlight the necessity to improve the current knowledge of this neglected retrovirus, encouraging for more studies on vaccine development aiming the to eliminate this human threat. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier (CRD42021270412).


Asunto(s)
Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Humanos , Infecciones por HTLV-I/prevención & control , Bases de Datos Factuales , Inmunización , Desarrollo de Vacunas
8.
Epidemiol. serv. saúde ; 32(2): e2022614, 2023. tab, graf
Artículo en Inglés, Portugués | LILACS | ID: biblio-1506220

RESUMEN

O relato descreveu o primeiro curso presencial visando capacitar profissionais de saúde pública na realização de vigilância genômica em tempo real, durante períodos pandêmicos. Relato de experiência sobre um curso teórico-prático com foco em pesquisa e vigilância genômica, incluindo tecnologias de sequenciamento móvel, bioinformática, filogenética e modelagem epidemiológica. O evento contou com 162 participantes e foi o primeiro grande treinamento presencial realizado durante a epidemia de covid-19 no Brasil. Não foi detectada infecção pelo SARS-CoV-2 ao final do evento em nenhum participante, sugerindo a segurança e efetividade de todas as medidas de segurança adotadas. Os resultados do evento sugerem que é possível executar capacitação profissional com segurança durante pandemias, desde que seguidos todos os protocolos de segurança.


The objective of this report was to describe the first face-to-face course aimed at training public health professionals in performing real-time genomic surveillance during the pandemic period. Experience report on a theoretical-practical course focusing on genomic research and surveillance, including mobile sequencing technologies, bioinformatics, phylogenetics and epidemiological modeling. There were 162 participants in the event and it was the first major face-to-face training course conducted during the COVID-19 epidemic in Brazil. No cases of SARS-CoV-2 infection was detected among the participants at the end of the event, suggesting the safety and effectiveness of all safety measures adopted. The results of this experience suggest that it is possible to conduct professional training safely during pandemics, as long as all safety protocols are followed.


Este estudio tuvo como objetivo describir el primer curso presencial para capacitar a los profesionales de la salud pública para llevar a cabo la vigilancia genómica en tiempo real durante los períodos de pandemia. Este es un informe de experiencia en un curso teórico-práctico centrado en la investigación y vigilancia genómica, que incluye secuenciación móvil, bioinformática, filogenética y tecnologías de modelado epidemiológico. Este evento contó con la asistencia de 162 participantes y fue la primera gran capacitación presencial realizada durante la epidemia de COVID-19 en Brasil. No se detectó infección por SARS-CoV-2 al final del evento en ningún participante, lo que sugiere la seguridad y efectividad de todas las medidas de seguridad adoptadas. Por lo tanto, los resultados del evento sugieren que es posible realizar entrenamientos profesionales de manera segura durante pandemias, siempre y cuando se sigan todos los protocolos de seguridad.


Asunto(s)
Humanos , Masculino , Femenino , Transferencia de Tecnología , Biología Computacional/educación , Capacitación de Recursos Humanos en Salud , Capacitación Profesional , COVID-19/epidemiología , Brasil/epidemiología , Salud Pública , Personal de Salud/educación , Genómica/educación , Epidemias , SARS-CoV-2/aislamiento & purificación , COVID-19/genética
9.
Int J STD AIDS ; 33(6): 530-543, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35333098

RESUMEN

Human papillomavirus (HPV) and human immunodeficiency virus (HIV) infections are sexually transmitted. There are several HPV genotypes and clinical manifestations. Determining which genotypes circulate worldwide and/or in specific geographic areas can help with prevention programs and vaccine distribution. This systematic review aimed to investigate the most frequent anal and cervical HPV genotypes in women co-infected with HPV/HIV. The PubMed, Scientific Electronic Library Online, and Latin American and Caribbean Literature in Health Sciences databases were used to search for articles published between January 2015 and August 2021, and the included articles followed the defined selection criteria. Based on the 51 articles included, HPV16 was the most prevalent (41%) genotype, followed by HPV52 (17%) and HPV58 (14%). Based on the comparative analyses of the HIV-negative women with HPV and the HPV/HIV co-infected groups, HPV16 was frequent in both groups; HPV58, HPV31, and HPV52 were more frequent in the co-infected group; and HPV18 was more common in HIV-negative women with HPV. HPV/HIV co-infected women most frequently presented the HPV genotypes 16, 58, and 52, whereas HIV-negative women with HPV had a higher frequency of HPV16, HPV18, and HPV52 genotypes. The results indicate the importance of genotype surveillance as a strategy to improve preventive measures against HPV infection and its complications. International Prospective Register of Systematic Reviews (PROSPERO) registration number: CRD42020220121.


Asunto(s)
Alphapapillomavirus , Coinfección , Infecciones por VIH , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Coinfección/complicaciones , Coinfección/epidemiología , Femenino , Genotipo , VIH , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Papillomavirus Humano 16/genética , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Prevalencia , Neoplasias del Cuello Uterino/epidemiología
10.
Arch Virol ; 166(11): 3037-3048, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34415436

RESUMEN

Human T-lymphotropic virus type 1 (HTLV-1) was the first human retrovirus described. The viral factors involved in the different clinical manifestations of infected individuals are still unknown, and in this sense, sequencing technologies can support viral genome studies, contributing to a better understanding of infection outcome. Currently, several sequencing technologies are available with different approaches. To understand the methodological advances in the HTLV-1 field, it is necessary to organize a synthesis by a rigorous review. This systematic literature review describes different technologies used to generate HTLV-1 sequences. The review follows the PRISMA guidelines, and the search for articles was performed in PubMed, Lilacs, Embase, and SciELO databases. From the 574 articles found in search, 62 were selected. The articles showed that, even with the emergence of new sequencing technologies, the traditional Sanger method continues to be the most commonly used methodology for generating HTLV-1 genome sequences. There are many questions that remain unanswered in the field of HTLV-1 research, and this reflects on the small number of studies using next-generation sequencing technologies, which could help address these gaps. The data compiled and analyzed here can help research on HTLV-1, assisting in the choice of sequencing technologies.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano/genética , Análisis de Secuencia de ARN/métodos , Brasil , Genoma Viral , Infecciones por HTLV-I/virología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
11.
J Med Virol ; 93(11): 6418-6423, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33835501

RESUMEN

The human T-cell lymphotropic virus type-1 (HTLV-1) is associated with severe pathologies, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), adult T-cell leukemia-lymphoma (ATLL), and infective dermatitis associated with the HTLV-1 (IDH). Interestingly, HTLV-1 infection does not necessarily imply the development of pathological processes and it is unknown why some patients remain asymptomatic carriers (AC). Despite some mutations in the HTLV-1 genome appear to influence the outcome of HTLV-1, there are few studies that characterize molecularly the hbz region. This study aimed to perform the molecular characterization of hbz gene isolated from patients with different clinical outcomes. A total of 15 sequences were generated and analyzed with 571 sequences previously published. The analises showed that the R119Q mutation seems to be related to HTLV-1 clinical conditions since the frequency of this HBZ mutation is significantly different in comparison between AC with HAM/TSP and ATLL. The R119Q mutation is possibly a protective factor as the frequency is higher in AC sequences.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Variación Genética , Genoma Viral , Infecciones por HTLV-I/virología , Virus Linfotrópico T Tipo 1 Humano/genética , Mutación , Proteínas de los Retroviridae/genética , Adulto , Genómica , Infecciones por HTLV-I/sangre , Infecciones por HTLV-I/clasificación , Humanos , Leucocitos Mononucleares/virología , Paraparesia Espástica Tropical/virología , Carga Viral
13.
PLoS Negl Trop Dis ; 14(7): e0008467, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32693402

RESUMEN

BACKGROUND: Chikungunya virus (CHIKV) has caused worldwide epidemics that impose a major burden on health systems. Approximately half of infected individuals develop chronic debilitating arthralgia, affecting their quality of life. Here, we identified the relevant clinical and demographic variables in the acute phase of CHIKV infection prospectively linked to chronic arthralgia to elaborate a prognostic scoring system. METHODS: Acute CHIKV infection cases (n = 134) confirmed by serology or molecular test were examined <10 days of disease onset and followed for one year to evaluate for disease progression. Potential risk factors for chronic arthralgia were evaluated by multivariate analysis to develop a prognostic scoring system, which was subsequently tested in an independent validation cohort consisting of 42 individuals. RESULTS: A total of 107 out of 134 (80%) acute CHIKV-confirmed cases from the derivation cohort were re-examined one year after enrollment. Chronic arthralgia post-CHIKV infection was diagnosed in 64 (60%). Five of the 12 parameters evaluated in the acute phase were statistically associated with persistent arthralgia and were further tested by Bayesian analysis. These variables were weighted to yield a prognosis score denominated SHERA (Sex, Hypertension, Edema, Retroocular pain, Age), which exhibited 81.3% accuracy in predicting long-term arthralgia post-CHIKV infection in the derivation cohort, and 76.5% accuracy in the validation cohort. CONCLUSIONS: The simplified and externally validated prognostic scoring system, SHERA, is a useful method to screen acutely CHIKV-infected patients at elevated risk of chronic arthralgia who will benefit from specific interventions. This tool could guide public health policies, particularly in resource-constrained settings.


Asunto(s)
Artralgia/etiología , Fiebre Chikungunya/complicaciones , Adulto , Artralgia/patología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Riesgo , Adulto Joven
14.
Parasit Vectors ; 13(1): 44, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32000835

RESUMEN

BACKGROUND: Leishmania spp. are digenetic parasites capable of infecting humans and causing a range of diseases collectively known as leishmaniasis. The main mechanisms involved in the development and permanence of this pathology are linked to evasion of the immune response. Crosstalk between the immune system and particularities of each pathogenic species is associated with diverse disease manifestations. Lipophosphoglycan (LPG), one of the most important molecules present on the surface of Leishmania parasites, is divided into four regions with high molecular variability. Although LPG plays an important role in host-pathogen and vector-parasite interactions, the distribution and phylogenetic relatedness of the genes responsible for its synthesis remain poorly explored. The recent availability of full genomes and transcriptomes of Leishmania parasites offers an opportunity to leverage insight on how LPG-related genes are distributed and expressed by these pathogens. RESULTS: Using a phylogenomics-based framework, we identified a catalog of genes involved in LPG biosynthesis across 22 species of Leishmania from the subgenera Viannia and Leishmania, as well as 5 non-Leishmania trypanosomatids. The evolutionary relationships of these genes across species were also evaluated. Nine genes related to the production of the glycosylphosphatidylinositol (GPI)-anchor were highly conserved among compared species, whereas 22 genes related to the synthesis of the repeat unit presented variable conservation. Extensive gain/loss events were verified, particularly in genes SCG1-4 and SCA1-2. These genes act, respectively, on the synthesis of the side chain attached to phosphoglycans and in the transfer of arabinose residues. Phylogenetic analyses disclosed evolutionary patterns reflective of differences in host specialization, geographic origin and disease manifestation. CONCLUSIONS: The multiple gene gain/loss events identified by genomic data mining help to explain some of the observed intra- and interspecies variation in LPG structure. Collectively, our results provide a comprehensive catalog that details how LPG-related genes evolved in the Leishmania parasite specialization process.


Asunto(s)
Genoma de Protozoos , Glicoesfingolípidos/biosíntesis , Glicoesfingolípidos/genética , Leishmania/fisiología , Trypanosomatina/genética , Secuencia de Bases , Evolución Biológica , Minería de Datos , Glicoesfingolípidos/química , Humanos , Leishmania/clasificación , Leishmania/genética , Funciones de Verosimilitud , Filogenia , ARN Protozoario/química , Trypanosomatina/clasificación , Trypanosomatina/fisiología
15.
Infect Genet Evol ; 79: 104166, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31883457

RESUMEN

The HTLV-1 is the first human retrovirus and is associated with several clinical syndromes, however, the pathogenesis of these clinical manifestations is still not fully understood. Furthermore, there are few complete genomes publicly available, about 0.12 complete genomes per 10,000 infected individuals and the databases have a major deficiency of sequences information. This study generated and characterized 31 HTLV-1 complete genomes sequences derived from individuals with Tropical Spastic Paraparesis/HTLV-1-Associated Myelopathy (TSP/HAM), Adult T-cell leukemia/lymphoma (ATL), infective dermatitis associated to HTLV-1 (IDH) and asymptomatic patients. These sequences are associated to clinical and epidemiological information about the patients. The sequencing data generated on Ion Torrent PGM platform were assembled and mapped against the reference HTLV-1 genome. These sequences were genotyped as Cosmopolitan subtype, Transcontinental subgroup. We identified the variants in the coding regions of the genome of the different clinical profiles, however, no statistical relation was detected. This study contributed to increase of HTLV-1 complete genomes in the world. Furthermore, to better investigate the contribution of HTLV-1 mutations for the disease outcome it is necessary to evaluate the interaction of the viral genome and characteristics of the human host.


Asunto(s)
Dermatitis/virología , Virus Linfotrópico T Tipo 1 Humano/clasificación , Leucemia-Linfoma de Células T del Adulto/virología , Paraparesia Espástica Tropical/virología , Secuenciación Completa del Genoma/métodos , Adolescente , Adulto , Anciano , Niño , Femenino , Variación Genética , Tamaño del Genoma , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Virus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Adulto Joven
17.
AIDS Res Hum Retroviruses ; 35(9): 881-884, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31154802

RESUMEN

The human T cell lymphotropic virus type 1 (HTLV-1) infects 5 to 10 million individuals and remains without specific treatment. This retrovirus genome is composed of the genes gag, pol, env, and a region known as pX. This region contains four open reading frames (ORFs) that encode specific proteins. The ORF-I produces the protein p12 and its cleavage product, p8. In this study, we analyzed the genetic diversity of 32 ORF-I sequences from patients with different clinical profiles. Seven amino acid changes with frequency over 5% were identified: G29S, P34L, L55F, F61L, S63P, F78L, and S91P. The identification of regions where the posttranslational sites were identified showed a high identity among the sequences and the amino acid changes exclusive of specific clinical profile were found in less than 5% of the samples. We compare the findings with 2.406 sequences available in GenBank. The low overall genetic diversity found suggested that this region could be used in the HTLV-1 vaccine development.


Asunto(s)
Variación Genética , Infecciones por HTLV-I/virología , Virus Linfotrópico T Tipo 1 Humano/genética , Sistemas de Lectura Abierta , Proteínas Reguladoras y Accesorias Virales/genética , Infecciones Asintomáticas , Bases de Datos de Ácidos Nucleicos , Endocarditis/virología , Humanos , Leucemia-Linfoma de Células T del Adulto/virología , Mutación , Paraparesia Espástica Tropical/virología
18.
Infect Genet Evol ; 45: 420-425, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27553711

RESUMEN

The region known as pX in the 3' end of the human T-cell lymphotropic virus type 1 (HTLV-1) genome contains four overlapping open reading frames (ORF) that encode regulatory proteins. HTLV-1 ORF-I produces the protein p12 and its cleavage product p8. The functions of these proteins have been linked to immune evasion and viral infectivity and persistence. It is known that the HTLV-1 infection does not necessarily imply the development of pathological processes and here we evaluated whether natural mutations in HTLV-1 ORF-I can influence the proviral load and clinical manifestation of HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). For that, we performed molecular characterization, datamining and phylogenetic analysis with HTLV-1 ORF-I sequences from 156 patients with negative or positive diagnosis for HAM/TSP. Our analyses demonstrated that some mutations may be associated with the outcome of HAM/TSP (C39R, L40F, P45L, S69G and R88K) or with proviral load (P34L and F61L). We further examined the presence of mutations in motifs of HBZ and observed that P45L mutation is located within the HBZ nuclear localization signal and was found more frequently between patients with HAM/TSP and high proviral load. These results indicate that some natural mutations are located in functional domains of ORF-I and suggests a potential association between these mutations and the proviral loads and development of HAM/TSP. Therefore it is necessary to conduct functional studies aimed at evaluating the impact of these mutations on the virus persistence and immune evasion.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano/genética , Sistemas de Lectura Abierta/genética , Paraparesia Espástica Tropical/epidemiología , Paraparesia Espástica Tropical/virología , Humanos , Epidemiología Molecular , Mutación/genética , ARN Viral/análisis , ARN Viral/genética , Carga Viral
19.
AIDS Res Hum Retroviruses ; 31(9): 913-20, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26123053

RESUMEN

Characterizing the impact of HIV transmission routes on viral genetic diversity can improve the understanding of the mechanisms of virus evolution and adaptation. HIV vertical transmission can occur in utero, during delivery, or while breastfeeding. The present study investigated the phylodynamics of the HIV-1 env gene in mother-to-child transmission by analyzing one chronically infected pair from Brazil and three acutely infected pairs from Zambia, with three to five time points. Sequences from 25 clones from each sample were obtained and aligned using Clustal X. ML trees were constructed in PhyML using the best evolutionary model. Bayesian analyses testing the relaxed and strict molecular clock were performed using BEAST and a Bayesian Skyline Plot (BSP) was construed. The genetic variability of previously described epitopes was investigated and compared between each individual time point and between mother and child sequences. The relaxed molecular clock was the best-fitted model for all datasets. The tree topologies did not show differentiation in the evolutionary dynamics of the virus circulating in the mother from the viral population in the child. In the BSP, the effective population size was more constant in time in the chronically infected patients while in the acute patients it was possible to detect bottlenecks. The genetic variability within viral epitopes recognized by the human immune system was considerably higher among the chronically infected pair in comparison with acutely infected pairs. These results contribute to a better understanding of HIV-1 evolutionary dynamics in mother-to-child transmission.


Asunto(s)
Genes env , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1/genética , Adulto , Teorema de Bayes , Brasil , Niño , Preescolar , Evolución Molecular , Femenino , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Zambia
20.
salvador; s.n; 2015. 57 p. ilus, tab.
Tesis en Portugués | LILACS | ID: biblio-1000961

RESUMEN

A leptospirose é a zoonose mais disseminada mundialmente por infectar diversas espécies diferentes de animais mamíferos. Apresenta 22 espécies identificadas, sendo dez patogênicas, cinco intermediarias e sete saprofiticas, além de apresentar mais de 250 sorovares diferentes. Em Salvador, Leptospira interrogans sorovar Copenhageni é a causadora da epidemia urbana na cidade e apresenta ratos como seu hospedeiro reservatório. As formas clínicas da leptospirose podem variar de assintomática a formas graves. As manifestações clínicas mais graves envolve o desenvolvimento da síndrome Hemorrágica pulmonar severa, e óbito do paciente. Estudos para entender as diferenças genéticas entre as diferentes espécies e sorovares é de extrema importância para identificar fatores de virulência da bactéria, genes que possam está associado aos diferentes formas clinicas, e sua capacidade de se adaptar aos diferentes ambientes. Neste trabalho foi estudado o genoma de dois importantes serovares de L. interrogans, o sorovar Copenhageni e o serovar Icterohaemorrhagiae, e suas diferenças genéticas e associação com dados clínicos e epidemiológicos. Um total de 141 isolados...


There are 22 different species of Leptospira spp. in which 10 are pathogenic, 5 intermediate and 7 saprophytic species. In Salvador the Leptospira interrogans sorovar Copenhageni is the main serovar detected, responsible for the urban epidemics, and has rats as their main host. The clinical manifestations of leptospirosis can vary from asymptomatic form to severe disease like pulmonary hemorrhagic syndrome, and death. Studies to understand de genetic differences among the species and serovars are of great importance to identify virulence factors, genes that could be related to the different clinical manifestations and its capacity to adapt in different environments. Here, the genome of two epidemiologically important serovar of the L. interrogans, the serovar Copenhageni and serovar Icterohaemorrhagiae, and their genetic differences and the association of these differences with epidemiological and clinical data were studied. A total of 141 strains...


Asunto(s)
Humanos , Genoma Humano/fisiología , Genoma Humano/inmunología , Leptospira/crecimiento & desarrollo , Leptospira/inmunología , Leptospira/patogenicidad , Leptospirosis/complicaciones , Leptospirosis/diagnóstico , Leptospirosis/inmunología , Leptospirosis/patología , Leptospirosis/transmisión
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