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1.
Genome Biol Evol ; 16(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38761112

RESUMO

The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (∼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies ∼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation.


Assuntos
Camelídeos Americanos , Animais , Camelídeos Americanos/genética , Ecossistema , Clima Desértico , Adaptação Fisiológica/genética , Genoma , Variação Genética , Regiões Antárticas , América do Sul , Evolução Molecular
2.
J Med Virol ; 94(5): 2296-2301, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35064576

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can generate a systemic inflammatory response, characterized by a cytokine storm and associated with an exaggerated release of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-17, all of which can affect the liver. Here, we aimed to evaluate the cytokine profiles of patients suffering from coronavirus disease (COVID)-19 and/or hepatitis. We subjected 87 patients to serology and/or polymerase chain reaction analysis for the hepatitis C virus. They were also tested for TNF-α, IL-6, and IL-17 using commercial immunoassay kits. The test results of the COVID-19/hepatitis C patients (n = 8) were compared with that of the negative controls (n = 28), hepatitis C patients (n = 29), and COVID-19 patients (n = 22). All COVID-19 patients (mono- and coinfected) expressed high levels of cytokines. The COVID-19/hepatitis patients exhibited higher levels of IL-6 (6.33 ± 3.9 pg/ml) and IL-17 (102.23 ± 2.7 pg/ml); however, TNF-α values were lower (68.08 ± 15.88 pg/ml), as compared with that of the hepatitis patients (p < 0.001), and lower than that of the COVID-19 patients and exceptionally for TNF-α (p < 0.05). These data highlight the importance of monitoring patients with hepatitis and COVID-19.


Assuntos
COVID-19 , Hepatite C , Síndrome da Liberação de Citocina , Citocinas , Hepacivirus , Humanos , SARS-CoV-2
3.
Invest. clín ; 51(3): 381-390, Sept. 2010. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-574450

RESUMO

Borrelia burgdorferi es el agente causal de Borreliosis de Lyme, una enfermedad infecciosa multisistémica transmitida al humano por la picadura de garrapatas del género Ixodes. En los últimos años se ha postulado una posible asociación entre ésta espiroqueta y esclerodermia localizada (morfea). Sin embargo, los datos publicados no han proporcionado pruebas inequívocas de tal asociación. En Suramérica, incluida Venezuela (estado Zulia) se han detectado pruebas serológicas positivas en pacientes con morfea. El objetivo de este estudio fue buscar evidencia definitiva de la infección por Borrelia burgdorferi en pacientes con morfea, mediante la detección del ADN bacteriano en muestras de piel. En los 21 pacientes la PCR resultó negativa. La ausencia de amplificación de la secuencia blanco seleccionada en las muestras estudiadas no apoyan una asociación entre la infección por Borrelia burgdorferi y las lesiones escleróticas de morfea, pero tampoco descartan la posibilidad de una relación entre morfea y una genoespecie desconocida del complejo Borrelia burgdorferi sensu lato, entre morfea y una especie diferente de Borrelia o entre morfea y otra espiroqueta, como agente etiológico de la lesión en la localidad.


Borrelia burgdorferi is the causative agent of Lyme Borreliosis, an infectious multisystemic disease transmitted to humans by the Ixodes ticks bite. A possible association of Borrelia burgdorferi with localized scleroderma has been postulated. However, published data do not provide unequivocal results. Previus serologic analysis of patients with localized scleroderma in South American countries (including Venezuela), have been reported as yielding some reactivity. The present study looked for evidence of Borrelia burgdorferi infection in venezuelan patients with localized scleroderma, using the polymerase chain reaction to analyze 21 skin samples of patients with this skin condition. The results were negative in all the samples studied. Our data do not support an association of Borrelia burgdorferi infection and the sclerotic lesions of localized scleroderma; but do not rule out the possibility of a relationship between localized scleroderma and an unknown geno-specie of Borrelia burgdorferi sensu lato complex, a different Borrelia specie or a different spirochetal organism, as the etiological agents of the skin lesions in this area.


Assuntos
Humanos , Masculino , Feminino , Borrelia burgdorferi , Reação em Cadeia da Polimerase/métodos , Esclerodermia Localizada
4.
Invest Clin ; 51(3): 381-90, 2010 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-21305774

RESUMO

Borrelia burgdorferi is the causative agent of Lyme Borreliosis, an infectious multisystemic disease transmitted to humans by the Ixodes ticks bite. A possible association of Borrelia burgdorferi with localized scleroderma has been postulated. However, published data do not provide unequivocal results. Previous serologic analysis of patients with localized scleroderma in South American countries (including Venezuela), have been reported as yielding some reactivity. The present study looked for evidence of Borrelia burgdorferi infection in venezuelan patients with localized scleroderma, using the polymerase chain reaction to analyze 21 skin samples of patients with this skin condition. The results were negative in all the samples studied. Our data do not support an association of Borrelia burgdorferi infection and the sclerotic lesions of localized scleroderma; but do not rule out the possibility of a relationship between localized scleroderma and an unknown geno-specie of Borrelia burgdorferi sensu lato complex, a different Borrelia specie or a different spirochetal organism, as the etiological agents of the skin lesions in this area.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Doença de Lyme/complicações , Doença de Lyme/microbiologia , Reação em Cadeia da Polimerase , Esclerodermia Localizada/microbiologia , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos , Venezuela
5.
Invest. clín ; 47(3): 283-288, sept. 2006. tab
Artigo em Inglês | LILACS | ID: lil-461375

RESUMO

En los últimos años se ha postulado una posible asociación entre Borrelia burgdorferi ( Bb ) y esclerodermia localizada (morfea). Sin embargo, los datos publicados no han proporcionado pruebas inequívocas de tal asociación. En Suramérica se han realizado estudios serológicos que han evidenciado resultados positivos. El objetivo de este estudio fue buscar evidencia de la infección por Bb en pacientes venezolanos con morfea, mediante la detección de anticuerpos antibacterianos, usando el protocolo de dos pasos recomendado por el Center for Disease Control and Prevention de Atlanta (Estados Unidos). Veintiún muestras de suero de pacientes con morfea y veintiún muestras de sujetos sanos (control) fueron analizadas. Cuatro muestras resultaron ELISA positivas: tres correspondieron a pacientes con morfea y una, a un sujeto control. Todas las muestras ELISA positivas fueron negativas en la prueba IgG Western Blot. Los resultados obtenidos no soportan una asociación entre la infección por Bb y las lesiones escleróticas de morfea, pero tampoco descartan la posibilidad de una relación entre morfea y una genoespecie desconocida del complejo Bb sensulato, entre morfea y una especie diferente de Borrelia o entre morfea y otra espiroqueta, como agente etiológico de la lesión en la localidad


Assuntos
Masculino , Feminino , Humanos , Borrelia burgdorferi , Doença de Lyme , Esclerodermia Localizada , Medicina , Venezuela
6.
Invest Clin ; 47(3): 283-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17672287

RESUMO

A possible association of Borrelia burgdorferi (Bb) with localized scleroderma (LS) has been postulated. However, the published data do not provide unequivocal results. Previous serologic analysis in LS patients in South American countries yielded positive results. The present study in our laboratory looked for evidence of Bb in LS patients in Venezuela, by antibacterial antibodies detection using the two-tiered approach as recommended by the Center for Disease Control and Prevention of Atlanta (United States). Twenty one serum samples from LS patients and twenty one samples from healthy individuals were analyzed. Four serum samples were ELISA positive: three from patients with LS and one from a healthy control. All ELISA positive samples were negative by IgG Western Blot. Our data do not support an association of Bb infection and the sclerotic lesions of LS; but do not rule out the possibility of a relationship between LS and an unknown geno-specie of Bb sensu lato complex, a different Borrelia specie or a different spirochetal organism, as the etiological agents of the skin lesions in the area.


Assuntos
Esclerodermia Localizada/sangue , Adolescente , Adulto , Idoso , Anticorpos Antibacterianos , Borrelia burgdorferi/imunologia , Criança , Humanos , Pessoa de Meia-Idade , Venezuela
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