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1.
Ann Bot ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39196773

RESUMEN

BACKGROUND AND AIMS: Species delimitation can be challenging when analysing recently diverged species, especially those taxonomically synonymised due to morphological similarities. We aimed to untangle the relationships between two grassland species, Petunia guarapuavensis and Petunia scheideana, exploring the dynamics of fast divergence and addressing their species delimitation. METHODS: We used a low-coverage genome sequencing and population genomic approach to distinguish species and populations between P. guarapuavensis and P. scheideana. Our analysis focused on detecting structuration, hybridisation/introgression, and phylogenetic patterns. We employed demographic models to support species delimitation while exploring potential phylogeographic barriers influencing gene flow. KEY RESULTS: Our findings indicated differentiation between the two species and revealed another lineage, which was phylogenetically distinct from the others and had no evidence of gene flow with them. The presence of a river acted as a phylogeographic barrier, limiting gene flow and allowing for structuration between closely related lineages. The optimal species delimitation scenario involved secondary contact between well-established lineages. CONCLUSIONS: The rapid divergence observed in these Petunia species explains the lack of significant morphological differences, as floral diagnostic traits in species sharing the pollinators tend to evolve more slowly. This study highlights the complexity of species delimitation in recently diverged groups and emphasises the importance of genomic approaches in understanding evolutionary relationships and speciation dynamics.

2.
Genet Mol Biol ; 46(3 Suppl 1): e20230159, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37931074

RESUMEN

Genetic polymorphism sharing between closely related and sympatric plant species could result from common ancestry, ancient or recent hybridization. Here we analyzed four Petunia species from the subtropical highland grasslands in southern South America based on nuclear diversity to disentangle the causes of high polymorphism sharing between them. We genotyped microsatellite loci, employed population genetic methods to estimate variability, species limits, and ancient and recent gene flow, and assigned individuals to genetic and taxonomic groups. Finally, we modeled evolutionary processes to determine the impact of Quaternary climate changes on species phylogenetic relationships. Our results indicated that genetic diversity was strongly influenced by expansion and habitat fragmentation during the Quaternary cycles. The extensive polymorphism sharing is mainly due to species' common ancestry, and we did not discard ancient hybridization. Nowadays, niche differentiation is the primary driver for maintaining genetic and morphological limits between the four analysed Petunia species and there is no recent gene flow between them.

3.
J Med Virol ; 91(12): 2125-2133, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31429939

RESUMEN

Immunosuppressive therapy causes severe impairment of host defense and diarrhea is a frequent complication in renal transplant recipients. This study aimed to describe the occurrence of Rotavirus A (RVA) and Human Bocavirus (HBoV) in fecal samples of immunosuppressed patients submitted to renal transplantation during posttransplant follow-up. A longitudinal study was carried out involving a 25-patient cohort, selected for kidney transplantation. A total of 126 fecal samples were collected between May 2014 and May 2016. Molecular techniques were used to detect and characterize circulating RVA and HBoV genotypes and statistical analysis were applied to verify the association between epidemiological and clinical characteristics. The prevalence of RVA and HBoV was 24% (6/25) and 40% (10/25), respectively. Among RVA and HBoV positive cases, the majority was female; did not conduct water treatment nor had adequate sewage facilities. The most detected genotypes were RVA G3 (62.5%) and HBoV-3 (95%). Phylogenetic analysis of HBoV strains indicated that studied samples were similar to those found in Asian and American countries. The present study point out the circulation of these viral agents among immunosuppressed individuals and these findings will enable the construction of new knowledge and care perspectives on the cause of diarrhea in this population.


Asunto(s)
Heces/virología , Bocavirus Humano/aislamiento & purificación , Huésped Inmunocomprometido , Trasplante de Riñón/efectos adversos , Rotavirus/aislamiento & purificación , Adulto , Brasil/epidemiología , Coinfección/epidemiología , Coinfección/virología , Femenino , Genotipo , Bocavirus Humano/genética , Humanos , Estudios Longitudinales , Masculino , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/virología , Filogenia , Prevalencia , Rotavirus/genética , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Análisis de Secuencia de ADN , Receptores de Trasplantes/estadística & datos numéricos
4.
Arch Virol ; 164(8): 2107-2117, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31144039

RESUMEN

Species A rotavirus still remains a major cause of acute gastroenteritis in infants and young children. Globally, six genotypes (G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]) account for >90% of circulating strains; however, genotype G12 in combination with P[6] or P[9] has been detected at increasing rates. We sought to broaden our knowledge about the rotavirus strains circulating during the early post-vaccine-introduction period. Stool samples were obtained from children hospitalised for acute gastroenteritis in Belém, Northern Brazil, from May 2008 to May 2011 and examined by reverse transcription polymerase chain reaction and nucleotide sequencing. A total of 122 out of the original 1076 rotavirus strains were judged to be non-typeable in the first analysis and were therefore re-examined. G2P[4] was the most prevalent genotype (58.0%), followed by G1P[8] (16.9%), and G12P[6] (7.5%). G12P[6] strains were identified at similar rates during the first (2.5%) and second (3.9%) years, and the rate jumped to 15.6% in the third year. Analysis of VP7 sequences of the G12P[6] strains showed that they belonged to lineage III. In addition, co-circulating G12P[6] strains displaying long and short RNA patterns were found to belong to the Wa-like and DS-1-like constellation, respectively. Additional unusual circulating strains G12P[9] and G3P[9] were also identified. This hospital-based study showed a high prevalence of G12P[6] strains in the third year of surveillance. Our results highlight the need for continuous longitudinal monitoring of circulating rotavirus strains after introduction of rotavirus vaccines in Brazil and elsewhere.


Asunto(s)
Gastroenteritis/virología , Rotavirus/genética , Antígenos Virales/inmunología , Brasil , Niño , Niño Hospitalizado , Gastroenteritis/inmunología , Genotipo , Humanos , Epidemiología Molecular/métodos , Filogenia , Prevalencia , ARN Viral/genética , Rotavirus/inmunología , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/virología , Vacunas contra Rotavirus/inmunología , Análisis de Secuencia de ADN/métodos
5.
BMC Pediatr ; 19(1): 193, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31189470

RESUMEN

BACKGROUND: Rotavirus antigenemia and RNAemia (the presence of rotavirus RNA in serum) have been commonly identified among paediatric patients with acute gastroenteritis. In this study we examined the association between rotavirus antigenemia and clinical features, and sought to determine the genotypes of rotaviruses detected in paired stool and serum samples. METHODS: Paired stool and serum samples were obtained from children hospitalised for acute gastroenteritis in Belém, Brazil, between June 2012 and June 2015. The 20-point Vesikari scoring system was used to assess the disease severity upon a retrospective medical record review. Stool and serum samples were primarily screened for the presence of rotavirus antigen using a commercial ELISA assay. The rotavirus isolates from stool and serum samples were genotyped by using the classical reverse-transcriptase polymerase chain reaction (RT-PCR) and/or through nucleotide sequencing of VP4 and VP7 genes. Viral load was estimated using real-time RT-PCR. RESULTS: In total rotavirus antigen was detected in 109 (24.2%) stool samples from 451 children, whereas antigenemia occurred in 38.5% (42/109) of these patients. We demonstrated that patients positive for rotavirus RNA in paired stool and serum samples were more likely to have a higher frequency of vomiting episodes in a 24-h period (p = 0.0035). Our findings also suggested that children not vaccinated against rotavirus are more likely to develop antigenemia, as compared to those given at least one vaccine dose (p = 0.0151). G12P [8] and G2P [4] genotypes were predominant throughout the study period, accounting for 52.3% (57/109) and 27.5% (30/109) of the typed isolates, respectively. Ten stool-serum pairs could be typed for VP4 and VP7 genes. Seven of these pairs showed concordant results with G2P [4] genotype being detected in stool and serum samples, whereas discrepancies between genotypes (G2P [4]/G2P[NT] and G12P [8]/G2P[NT]) were seen in three pairs. CONCLUSIONS: Rotavirus antigenemia and RNAemia occur in a significant number of children hospitalised for acute gastroenteritis in Belém, Brazil, and may contribute to a greater disease severity, particularly translated into a greater number of vomiting episodes. This study documented a high concordance of genotypes detected in a subgroup of paired stool and serum samples.


Asunto(s)
Antígenos Virales/análisis , Gastroenteritis/inmunología , ARN Viral/análisis , Infecciones por Rotavirus/inmunología , Rotavirus/inmunología , Enfermedad Aguda , Antígenos Virales/sangre , Brasil , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Heces/química , Heces/virología , Femenino , Gastroenteritis/complicaciones , Gastroenteritis/virología , Genotipo , Hospitalización , Humanos , Masculino , Estudios Prospectivos , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/genética , Índice de Severidad de la Enfermedad , Vómitos/etiología
6.
J Med Virol ; 89(6): 974-981, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27862014

RESUMEN

The species A rotaviruses (RVA) are important gastroenteric pathogens that infect humans and animals. RVA genotype G3P[9] has been described in human-animal reassortment events, and the complexity of its hosts motivates the genetic investigation of this strain. Therefore, the aim of this study is to analyse a G3P[9] sample that was detected in a child with acute gastroenteritis. The 1A3739 sample featured the constellation G3P[9]-I18-R3-C3-Mx-A19-N3-T3-E3-H6. The sequence for VP3 gene was not obtained. The phylogeny showed a closer relationship among genes VP7, VP1, NSP3, NSP4, and NSP5 with genes of animal origin, such as chiropter, alpaca, equine, and simian. In addition, the genes VP6 and NSP1 belong to the new genotypes I18 and A19, respectively. The emergence of strains such as these can interfere with the effectiveness of the RVA vaccine, and continuous monitoring is therefore important. Additional studies are needed to determine the evolutionary source and to identify a possible reservoir of RVA in nature.


Asunto(s)
Gastroenteritis/virología , Genotipo , Virus Reordenados/genética , Infecciones por Rotavirus/virología , Rotavirus/genética , Preescolar , Evolución Molecular , Femenino , Humanos , Filogenia , Recombinación Genética , Rotavirus/aislamiento & purificación , Análisis de Secuencia de ADN
7.
J Med Virol ; 88(5): 782-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26466923

RESUMEN

The present study aimed to provide a molecular characterization of circulating rotavirus (RVA) strains in Rio Branco, Acre, in the post-rotavirus vaccination period, particularly with regard to the emerging, increasingly prevalent G12P[8] genotype. A total of 488 fecal specimens from diarrheic and non-diarrheic children were obtained between January and December 2012. RVA detection was initially performed using enzyme-linked immunosorbent assay (ELISA) method, followed by reverse-transcription polymerase chain reaction (RT-PCR) using specific primers. RVA was detected in 18.3% (44/241) of the children with acute diarrhea and in 1.2% (3/247) of the non-diarrheic children (P < 0.001), with overall RVA-positivity of 9.6% (47/488). The most common genotype was G2P[4] with 43.2% (19/44) of the diarrheic cases, followed by G12P[8] (27.3%, 12/44), G3P[6] (18.2%, 8/44), G3P[8] (4.5%, 2/44), and G12P[6] (2.3%, 1/44). G12 samples belonged to lineage III and were from children aged 4-52 months. All of these children had acute diarrhea associated with fever (83.3%, 10/12) and vomiting (66.7%, 8/12). Most of the cases occurred in August (58.3%, 7/12), 75% (9/12) of which having received the full vaccination scheme with Rotarix™. For the first time G12 was reported at relative high prevalence in Brazil. Our findings warrant further monitoring studies on the molecular characterization of circulating RVA strains after rotavirus vaccine introduction in Brazil and elsewhere, since the occurrence of either unusual our emerging genotypes may pose a challenge to vaccination strategies.


Asunto(s)
Genotipo , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus/administración & dosificación , Rotavirus/clasificación , Rotavirus/genética , Brasil/epidemiología , Preescolar , Ensayo de Inmunoadsorción Enzimática , Heces/virología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Epidemiología Molecular , Prevalencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/patología , Infecciones por Rotavirus/virología , Estaciones del Año
8.
Cytokine ; 88: 99-107, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27591510

RESUMEN

Although much research has been done related to biomarker discovery for tuberculosis infection, a set of biomarkers that can discriminate between active and latent TB diseases remains elusive. In the current study we correlate clinical aspects of TB disease with changes in the immune response as determined by biomarkers detected in plasma. Our study measured 18 molecules in human plasma in 17 patients with active disease (APTB), 14 individuals with latent tuberculosis infection (LTBI) and 16 uninfected controls (CTRL). We found that active tuberculosis patients have increased plasma levels of IL-6, IP-10, TNF-α, sCD163 and sCD14. Statistical analysis of these biomarkers indicated that simultaneous measurement of sCD14 and IL-6 was able to diagnose active tuberculosis infection with 83% accuracy. We also demonstrated that TNF-α and sCD163 were correlated with tuberculosis severity. We showed that the simultaneous detection of both plasma sCD14 and IL-6 is a promising diagnostic approach to identify APTB, and further, measurement of TNF-α and sCD163 can identify the most severe cases of tuberculosis.


Asunto(s)
Citocinas/sangre , Receptores de Lipopolisacáridos/sangre , Tetraspanina 30/sangre , Tuberculosis Pulmonar/sangre , Adulto , Biomarcadores/sangre , Femenino , Humanos , Masculino
9.
Arch Virol ; 161(8): 2263-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27154557

RESUMEN

The aim of this study was to detect rotavirus F (RVF) and rotavirus G (RVG) in fecal specimens of broiler chickens in Brazil. During 2008 and 2011, a total of 85 fecal samples were collected. The viral genome was extracted, followed by polyacrylamide gel electrophoresis (PAGE), reverse transcription polymerase chain reaction (RT-PCR), and nucleotide sequencing. Samples were screened for rotaviruses by PAGE, and RVF and RVG genome banding patterns were not seen. Using RT-PCR, it was found that 9.4 % (8/85) of the pools contained RVF, whereas 10.6 % (9/85) contained RVG. The predicted amino acid sequences of RVF and RVG from Brazilian samples were 94.4-95.7 % and 96.8-96.9 % identical, respectively, to those of prototypes from Germany. The detection of RVF and RVG in this study provides important epidemiological data about the simultaneous circulation of rotaviruses affecting broiler flocks in the Amazon region of Brazil.


Asunto(s)
Antígenos Virales/genética , Proteínas de la Cápside/genética , Heces/virología , Enfermedades de las Aves de Corral/virología , Infecciones por Rotavirus/veterinaria , Rotavirus/aislamiento & purificación , Animales , Antígenos Virales/metabolismo , Brasil , Proteínas de la Cápside/metabolismo , Pollos , Filogenia , Rotavirus/clasificación , Rotavirus/genética , Rotavirus/metabolismo , Infecciones por Rotavirus/virología
10.
J Antimicrob Chemother ; 70(6): 1774-83, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25687643

RESUMEN

OBJECTIVES: Although TB immunotherapy improves the results of conventional drug treatment, the effects of combining chemotherapy and immunotherapy have never been systematically evaluated. We used a comprehensive lung transcriptome analysis to directly compare the activity of combined chemotherapy and immunotherapy with that of single treatments in a mouse model of TB. METHODS: Mycobacterium tuberculosis-infected mice in the chronic phase of the disease (day 30) received: (i) isoniazid and rifampicin (drugs) daily for 30 days; (ii) DNA immunotherapy (DNA), consisting of four 100 µg injections at 10 day intervals; (iii) both therapies (DNA + drugs); or (iv) saline. The effects were evaluated 10 days after the end of treatment (day 70 post-infection). RESULTS: In all groups a systemic reduction in the load of bacilli was observed, bacilli became undetectable in the drugs and DNA + drugs groups, but the whole lung transcriptome analysis showed 867 genes exclusively modulated by the DNA + drugs combination. Gene enrichment analysis indicated that DNA + drugs treatment provided synergistic effects, including the down-regulation of proinflammatory cytokines and mediators of fibrosis, as confirmed by real-time PCR, ELISA, histopathology and hydroxyproline assay. CONCLUSIONS: Our results provide a molecular basis for the advantages of TB treatment using combined chemotherapy and DNA immunotherapy and demonstrate the synergistic effects obtained with this strategy.


Asunto(s)
Terapia Combinada/métodos , Quimioterapia/métodos , Inmunoterapia/métodos , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/inmunología , Tuberculosis/terapia , Animales , Antituberculosos/administración & dosificación , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Isoniazida/administración & dosificación , Pulmón/microbiología , Pulmón/patología , Ratones Endogámicos BALB C , Rifampin/administración & dosificación , Resultado del Tratamiento , Vacunas de ADN/administración & dosificación
11.
J Med Virol ; 87(8): 1303-10, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25879653

RESUMEN

The monovalent human rotavirus (RV) vaccine, RIX4414 (Rotarix™, GlaxoSmithKline Biologicals) was introduced into Brazil's Expanded Program on Immunization in March 2006. One year after vaccine introduction, the G2P[4] strain was found to be predominant, with an apparent extinction of many non-G2 strains. This study investigated the diversity of circulating strains in the three years following RIX4414 introduction. Between May 2008 and May 2011, stool samples were collected from children aged ≥12 weeks who were hospitalized for severe lab confirmed RV-gastroenteritis (≥3 liquid or semi-liquid motions over a 24-h period for <14 days, requiring ≥1 overnight hospital stay and intravenous rehydration therapy) in Belém, Brazil. RV-gastroenteritis was detected by ELISA and the G- and P-types were determined by RT-PCR assays. During the first year of surveillance nucleotide sequencing was used for typing those samples not previously typed by RT-PCR. A total of 1,726 of 10,030 severe gastroentertis hospitalizations (17.2%) were due to severe RVGE. G2P[4] was detected in 57.2% of circulating strains over the whole study period, however it predominated during the first 20 months from May 2008 to January 2009. G1P[8] increased in the last part of the study period from May 2010 to May 2011 and represented 36.6% (112/306) of the circulating strains. G2P[4] was the predominant RV strain circulating during the first 20 months of the study, followed by G1P[8]. These findings probably reflect a natural fluctuation in RV strains over time, rather than a vaccine-induced selective pressure.


Asunto(s)
Variación Genética , Genotipo , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus/administración & dosificación , Rotavirus/clasificación , Rotavirus/genética , Brasil/epidemiología , Estudios de Casos y Controles , Preescolar , Monitoreo Epidemiológico , Heces/virología , Femenino , Gastroenteritis/epidemiología , Gastroenteritis/prevención & control , Gastroenteritis/virología , Humanos , Lactante , Masculino , Epidemiología Molecular , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/virología , Análisis de Secuencia de ADN , Vacunas Atenuadas/administración & dosificación
12.
Vaccines (Basel) ; 12(7)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39066430

RESUMEN

Several technological approaches have been used to develop vaccines against COVID-19, including those based on inactivated viruses, viral vectors, and mRNA. This study aimed to monitor the maintenance of anti-SARS-CoV-2 antibodies in individuals from Brazil according to the primary vaccination regimen, as follows: BNT162b2 (group 1; 22) and ChAdOx1 (group 2; 18). Everyone received BNT162b2 in the first booster while in the second booster CoronaVac, Ad26.COV2.S, or BNT162b2. Blood samples were collected from 2021 to 2023 to analyze specific RBD (ELISA) and neutralizing antibodies (PRNT50). We observed a progressive increase in anti-RBD and neutralizing antibodies in each subsequent dose, remaining at high titers until the end of follow-up. Group 1 had higher anti-RBD antibody titers than group 2 after beginning the primary regimen, with significant differences after the 2nd and 3rd doses. Group 2 showed a more expressive increase after the first booster with BNT162B2 (heterologous booster). Group 2 also presented high levels of neutralizing antibodies against the Gamma and Delta variants until five months after the second booster. In conclusion, the circulating levels of anti-RBD and neutralizing antibodies against the two variants of SARS-CoV-2 were durable even five months after the 4th dose, suggesting that periodic booster vaccinations (homologous or heterologous) induced long-lasting immunity.

13.
Arch Virol ; 157(12): 2389-92, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22872050

RESUMEN

Noroviruses, a major cause of acute gastroenteritis outbreaks worldwide, are constantly evolving. This ability is reflected in the speed and efficiency with which these viruses spread and remain in the human population. The present study reports the detection of a novel recombination event among norovirus genotypes in Brazil in 2008. A strain detected in a stool sample from a child with norovirus-associated gastroenteritis, residing in an African-descendant semi-closed community of Pará State, was characterized as a novel intergenotype recombinant, GII.7/GII.20, as determined by partial sequencing and SimPlot analysis.


Asunto(s)
Población Negra , Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Norovirus/clasificación , Norovirus/genética , Virus Reordenados , Secuencia de Bases , Brasil/epidemiología , Infecciones por Caliciviridae/epidemiología , Heces/virología , Gastroenteritis/epidemiología , Humanos , Lactante , Datos de Secuencia Molecular , Filogenia
14.
Mol Immunol ; 148: 68-80, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35659727

RESUMEN

The successful establishment of HIV-1 infection is related to inflammasome blocking or inactivation, which can result in the viral evasion of the immune responses and formation of reservoirs in several tissues. In this sense, we aimed to evaluate the viral and cellular mechanisms activated during HIV-1 infection in human primary macrophages that allow an effective viral replication in these cells. We found that resting HIV-1-infected macrophages, but not those activated in classical or alternative patterns, released IL-1ß and other pro-inflammatory cytokines, and showed increased CXCL10 expression, without changes in the NLRP3, AIM2 or RIG-I inflammasome pathways. Also, similar levels of Casp-1, phosphorylated NF-κB (p65) and NLRP3 proteins were found in uninfected and HIV-1-infected macrophages. Likewise, no alterations were detected in ASC specks released in the culture supernatant after HIV-1 infection, suggesting that macrophages remain viable after infection. Using in silico prediction studies, we found that the HIV-1 proteins Gag and Vpr interact with several host proteins. Comparable levels of trans-LTB4 were found in the supernatants of uninfected and HIV-1-infected macrophages, whereas ROS production was impaired in infected cells, which was not reversed after the PMA stimulus. Immunofluorescence analysis showed structural alterations in the mitochondrial architecture and an increase of BIM in the cytoplasm of infected cells. Our data suggest that HIV-1 proteins Gag and Vpr, through interacting with cellular proteins in the early steps of infection, preclude the inflammasome activation and the development of effective immune responses, thus allowing the establishment of the infection.


Asunto(s)
Infecciones por VIH , VIH-1 , Infecciones por VIH/metabolismo , Humanos , Inflamasomas , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Infección Persistente
15.
Vaccines (Basel) ; 10(5)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35632447

RESUMEN

The COVID-19 pandemic is the biggest public health threat facing the world today. Multiple vaccines have been approved; however, the emergence of viral variants such as the recent Omicron raises the possibility of booster doses to achieve adequate protection. In Brazil, the CoronaVac (Sinovac, Beijing, China) vaccine was used; however, it is important to assess the immune response to this vaccine over time. This study aimed to monitor the anti-SARS-CoV-2 antibody responses in those immunized with CoronaVac and SARS-CoV-2 infected individuals. Samples were collected between August 2020 and August 2021. Within the vaccinated cohort, some individuals had a history of infection by SARS-CoV-2 prior to immunization, while others did not. We analyzed RBD-specific and neutralizing-antibodies. Anti-RBD antibodies were detected in both cohorts, with a peak between 45-90 days post infection or vaccination, followed by a steady decline over time. In those with a previous history of COVID-19, a higher, longer, more persistent response was observed. This trend was mirrored in the neutralization assays, where infection, followed by immunization, resulted in higher, longer lasting responses which were conditioned on the presence of levels of RBD antibodies right before the vaccination. This supports the necessity of booster doses of CoronaVac in due course to prevent serious disease.

16.
Future Microbiol ; 16: 847-862, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34318682

RESUMEN

Aim: To perform a molecular analysis of rotavirus A (RVA) G3P[6] strains detected in 2012 and 2017 in the Amazon region of Brazil. Materials & methods: Eighteen RVA G3P[6] strains were collected from children aged under 10 years hospitalized with acute gastroenteritis, and partial sequencing of each segment genome was performed using Sanger sequencing. Results: Phylogenetic analysis showed that all G3P[6] strains had a DS-1-like genotype constellation. Two strains had the highest nucleotide identities with equine-like G3P[6]/G3P[8] genotypes. Several amino acid alterations in VP4 and VP7 neutralizing epitopes of equine-like RVA G3P[6] strains were observed in comparison with vaccine strains. Conclusion: These findings suggest that equine-like RVA G3P[6] strains have been circulating in the Amazon region of Brazil as a result of direct importation, and support natural RVA evolutionary mechanisms.


Asunto(s)
Genoma Viral , Virus Reordenados , Rotavirus , Animales , Brasil , Niño , Caballos , Humanos , Filogenia , Rotavirus/genética , Rotavirus/aislamiento & purificación
17.
Infect Genet Evol ; 85: 104555, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32931954

RESUMEN

Acute gastroenteritis (AG) is responsible for 525,000 deaths worldwide in children under-5-years and is caused by the Human Cosavirus (HCoSV; family Picornaviridae, Genus Cosavirus). Although its health importance, a significant percentage of diarrhea cases (≈ 40 %) still of unknown etiology. In Brazil, few studies have reported HCoSV-A sequences analyzing partial 5' UTR. This study characterized the first near-complete genome of a Cosavirus A (strain AM326) from a child hospitalized with AG in Amazonas state, Northern Brazil. High throughput sequencing (HTS) was performed using the HiSeq™ 2500 platform (Illumina) in one fecal specimen collected from the Surveillance of Rotavirus Network of the Evandro Chagas Institute collected in 2017. Sequence reads were assembled by the De Novo approach using three distinct algorithmic (IDBA-UD, Spades, and MegaHit). The final contig was recovered from the HCoSV-AM326 sample revealing 7,735 nt in length (SRA number SRR12535029; GenBank MT023104) and the genetic characterization, as well as phylogenetic analysis demonstrated a new variant strain from Brazil, highlighting the association of HCoSV-A as a possible causative agent of AG. This finding demonstrates the importance of the metagenomic approach to elucidate cases of diarrhea without a defined etiology, as well as providing a better understanding about the virus genetics, evolution and epidemiology.


Asunto(s)
Gastroenteritis/diagnóstico , Gastroenteritis/virología , Infecciones por Picornaviridae/diagnóstico , Infecciones por Picornaviridae/virología , Picornaviridae/clasificación , Picornaviridae/genética , Enfermedad Aguda , Brasil , Niño , Genoma Viral , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Hospitalización , Humanos , Picornaviridae/aislamiento & purificación , ARN Viral
18.
Infect Genet Evol ; 79: 104151, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31870971

RESUMEN

Porcine group A rotavirus (RVA) strains SUI15A and SUI24A are suggested to have VP3 genes of human origin possessing DS-1-like backbone. The aim of the present study was to analyse the genome of two strains (SUI15A and SUI24A) and understand the evolution of a rare human-like M2 genotype in pigs. On partial genomic analysis, strains SUI24A (G3-P[13]-I5-R1-C1-M2-A8-N1-T7-E1-H1) and SUI15A (G3-P[x]-Ix-R1-C1-M2-Ax-Nx-T7-E1-H1) were found to have VP3 gene RVA different from those of typical porcine RVA strains described in Brazil and worldwide. This genotypic constellation was a novel constellation that has not been reported previously in both humans and pigs. Furthermore, on phylogenetic analysis, VP3 gene of strains appeared to be of human origin. Therefore, suggested to have evidence for human-to-porcine zooanthroponotic transmission.


Asunto(s)
Proteínas de la Cápside/genética , Infecciones por Rotavirus/transmisión , Rotavirus/clasificación , Porcinos/virología , Animales , Brasil , Haplotipos , Humanos , Filogenia , Rotavirus/genética , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/virología , Enfermedades de los Porcinos/virología , Zoonosis/virología
19.
J Med Microbiol ; 68(8): 1233-1239, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31215861

RESUMEN

PURPOSE: Human bocavirus (HBoV) is a DNA virus that is mostly associated with respiratory infections. However, because it has been found in stool samples, it has been suggested that it may be a causative agent for human enteric conditions. This underpins the continuous search for HBoVs, especially after the introduction of the rotavirus vaccine due to acute gastroenteritis cases related to emergent viruses, as HBoVs are more likely to be found in this post-vaccine scenario. Therefore, the aim of this study is to demonstrate the prevalence of HBoV in children aged less than 10 years with acute gastroenteritis in Brazil from November 2011 to November 2012. METHODOLOGY: Stool samples from hospitalized children ≤10 years old who presented symptoms of acute gastroenteritis were analysed for the presence of rotavirus A (RVA) by an enzyme-linked immunosorbent assay (ELISA), and for HBoV DNA by nested PCR. RESULTS: HBoV positivity was detected in 24.0 % (54/225) of samples. Two peaks of HBoV detection were observed in November 2011 and from July to September 2012. Co-infections between HBoV and rotavirus A were identified in 50.0 % (27/54) of specimens. Phylogenetic analysis identified the presence of HBoV-1 (94.8 %), HBoV-2 (2.6 %) and HBoV-3 (2.6 %) species, with only minor variations among them. CONCLUSION: Our findings provide evidence for the circulation of most HBoV genotypes (except HBoV-4) in the North Region of Brazil at a considerable rate and further investigations are necessary to improve our knowledge in the context of HBoV infections and their role in gastrointestinal diseases.


Asunto(s)
Gastroenteritis/epidemiología , Bocavirus Humano/genética , Epidemiología Molecular , Infecciones por Parvoviridae/epidemiología , Enfermedad Aguda , Brasil/epidemiología , Proteínas de la Cápside/genética , Niño , Preescolar , Coinfección/epidemiología , Coinfección/virología , ADN Viral/genética , Heces/virología , Femenino , Gastroenteritis/virología , Genotipo , Bocavirus Humano/clasificación , Bocavirus Humano/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Masculino , Infecciones por Parvoviridae/virología , Filogenia , Reacción en Cadena de la Polimerasa , Prevalencia , Rotavirus/inmunología , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Análisis de Secuencia de ADN
20.
Sci Rep ; 8(1): 5505, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29615725

RESUMEN

Monocytes are key cells in the immune dysregulation observed during human immunodeficiency virus (HIV) infection. The events that take place specifically in monocytes may contribute to the systemic immune dysfunction characterized by excessive immune activation in infected individuals, which directly correlates with pathogenesis and progression of the disease. Here, we investigated the immune dysfunction in monocytes from untreated and treated HIV + patients and associated these findings with epigenetic changes. Monocytes from HIV patients showed dysfunctional ability of phagocytosis and killing, and exhibited dysregulated cytokines and reactive oxygen species production after M. tuberculosis challenge in vitro. In addition, we showed that the expression of enzymes responsible for epigenetic changes was altered during HIV infection and was more prominent in patients that had high levels of soluble CD163 (sCD163), a newly identified plasmatic HIV progression biomarker. Among the enzymes, histone acetyltransferase 1 (HAT1) was the best epigenetic biomarker correlated with HIV - sCD163 high patients. In conclusion, we confirmed that HIV impairs effector functions of monocytes and these alterations are associated with epigenetic changes that once identified could be used as targets in therapies aiming the reduction of the systemic activation state found in HIV patients.


Asunto(s)
Epigénesis Genética , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/fisiología , Monocitos/inmunología , Adolescente , Adulto , Anciano , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Progresión de la Enfermedad , Activación Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Fagocitosis/genética , Receptores de Superficie Celular/metabolismo , Adulto Joven
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