26 research outputs found
Characterization of Leishmania spp. causing cutaneous leishmaniasis in Manaus, Amazonas, Brazil
In the State of Amazonas, American tegumentary leishmaniasis is endemic and presents a wide spectrum of clinical variability due to the large diversity of circulating species in the region. Isolates from patients in Manaus and its metropolitan region were characterized using monoclonal antibodies and isoenzymes belonging to four species of the parasite: Leishmania (Viannia) guyanensis, 73% (153/209); Leishmania (Viannia) braziliensis, 14% (30/209); Leishmania (Leishmania) amazonensis, 8% (17/209); and Leishmania (Viannia) naiffii, 4% (9/209). The most prevalent species was L. (V.) guyanensis. The principal finding of this study was the important quantity of infections involving more than one parasite species, representing 14% (29/209) of the total. The findings obtained in this work regarding the parasite are further highlighted by the fact that these isolates were obtained from clinical samples collected from single lesions
In memoriam of Ricardo Flores: The career, achievements, and legacy of an inspirational plant virologist
[EN] Ricardo Flores (1947-2020) focused his research on the identification, replication, pathogenesis, and evolution of viroids, the minimal non-protein-coding circular RNAs (250-400 nt) able to replicate and incite diseases in plants that are remarkable for being at the lowest step of the biological scale. He and his collaborators initially identified and characterized additional group members, adding six new ones to the family Pospiviroidae, and expanding the Avsunviroidae from one to four members. They showed that members of the second family "encode" ribozymes, a property that, together with others, makes them candidates for being the most primitive replicons that emerged on our planet 3500 million years ago. He also made important contributions regarding how viroids replicate, providing relevant data on the templates, enzymes, and ribozymes that mediate this process and on the mutation rate, which turned out to be the highest reported for any biological entity. More recently, he concentrated on the role that RNA silencing could play on viroid-host interactions, describing details of this process. Ricardo also worked on citrus tristeza virus, a widely different type of subcellular pathogen, and made important contributions on the structure, localization and functions of its unique p23 protein. His research has produced 170 original articles and reviews, according to Web of Science. He encouraged the scientific careers of a large number of researchers, and collaborated with many others, some of whom have recapitulated his scientific legacy in this review and contributed with other chapters in this special issue.This work was supported by the Spanish Agencia Estatal de Investigaci ' on (AEI) and Fondo Europeo de Desarrollo Regional (FEDER), grant number PID2020-115571RB-100. We apologize to colleagues whose work was not cited in this review due to the page limit.Pallás Benet, V.; Hernandez Fort, C.; Marcos, JF.; Daròs, J.; Ambrós, S.; Navarro, B.; Navarro Bohigues, JA.... (2022). In memoriam of Ricardo Flores: The career, achievements, and legacy of an inspirational plant virologist. Virus Research. 312(198718):1-9. https://doi.org/10.1016/j.virusres.2022.1987181931219871
Caracterização isoenzimática de isolados humanos de Leishmania sp (Kinetoplastida: Trypanosomatidae) dos municÃpios de Rio Preto da Eva e Manaus, Estado do Amazonas
Twenty-three isolates of Leishmania sp from patients in the municipalities of Rio Preto da Eva and Manaus were characterized and identified by means of isoenzyme electrophoresis and the degree of similarity between the organisms was analyzed. The results indicated that Leishmania guyanensis and Leishmania naiffi were present in these two environments and that the Leishmania naiffi samples were heterogenous
Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition
A unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009-2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world's planktonic ecosystems
HIV AND HCV COINFECTION: PREVALENCE, ASSOCIATED FACTORS AND GENOTYPE CHARACTERIZATION IN THE MIDWEST REGION OF BRAZIL
Estudo transversal sobre a prevalência, fatores associados e distribuição dos genótipos do HCV foi realizado em 848 pacientes infectados pelo HIV, recrutados em centros de referência na Região Centro-Oeste do Brasil. A taxa de prevalência de coinfecção HIV-HCV foi de 6,9% (IC 95%: 5,2-8,6). Na análise multivariada, o aumento da idade, o uso de drogas ilÃcitas (injetáveis e não injetáveis), história de transfusão de sangue antes de 1994, e ausência de companheiro constante foram fatores associados independentes e significativos para a coinfecção HIV-HCV. A análise filogenética baseada na região NS5B revelou a presença de dois principais genótipos do HCV em circulação: genótipos 1 (58,3%) e 3 (41,7%). A prevalência da coinfecção HIV-HCV foi menor do que as relatadas em estudos realizados com pacientes infectados pelo HIV em diferentes regiões do Brasil, devido ao fato de que o uso de drogas ilÃcitas não é modo frequente de transmissão do HIV neste Estado do Brasil. Triagem sorológica de pacientes HIV-positivos para HCV antes de iniciar o tratamento antirretroviral, identificação completa dos fatores associados e a implementação de programas eficazes de redução de danos são altamente recomendados para fornecer informações úteis, para o tratamento e para evitar a coinfecção com HCV nestes pacientes.A cross-sectional study on prevalence, associated factors and genotype distribution of HCV infection was conducted among 848 HIV-infected patients recruited at reference centers in the Midwest Region of Brazil. The prevalence rate of HIV-HCV coinfection was 6.9% (95% CI: 5.2 to 8.6). In multivariable analysis, increasing age, use of illicit drugs (injection and non-injection), a history of blood transfusion before 1994, and the absence of a steady partnership were significant independent associated factors for HIV-HCV coinfection. The phylogenetic analysis based on the NS5B region revealed the presence of two major circulating genotypes of HCV: genotypes 1 (58.3%) and 3 (41.7%). The prevalence of HIV-HCV coinfection was lower than those reported in studies conducted with HIV-infected patients in different regions of Brazil, due to the fact that illicit drug use is not a frequent mode of HIV transmission in this region of Brazil. Serologic screening of HIV-patients for HCV before initiating antiretroviral treatment, a comprehensive identification of associated factors, and the implementation of effective harm reduction programs are highly recommended to provide useful information for treatment and to prevent HCV coinfection in these patients