48 research outputs found

    Systematics of the Neotropical Genus Leptodactylus Fitzinger, 1826 (Anura: Leptodactylidae): Phylogeny, the Relevance of Non-molecular Evidence, and Species Accounts

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    A phylogeny of the species-rich clade of the Neotropical frog genus Leptodactylus sensu stricto is presented on the basis of a total evidence analysis of molecular (mitochondrial and nuclear markers) and non-molecular (adult and larval morphological and behavioral characters) sampled from > 80% of the 75 currently recognized species. Our results support the monophyly of Leptodactylus sensu stricto, with Hydrolaetare placed as its sister group. The reciprocal monophyly of Hydrolaetare and Leptodactylus sensu stricto does not require that we consider Hydrolaetare as either a subgenus or synonym of Leptodactylus sensu lato. We recognize Leptodactylus sensu stricto, Hydrolaetare, Adenomera, and Lithodytes as valid monophyletic genera. Our results generally support the traditionally recognized Leptodactylus species groups, with exceptions involving only a few species that are easily accommodated without proposing new groups or significantly altering contents. The four groups form a pectinate tree, with the Leptodactylus fuscus group diverging first, followed by the L. pentadactylus group, which is sister to the L. latrans and L. melanonotus groups. To evaluate the impact of non-molecular evidence on our results, we compared our total evidence results with results obtained from analyses using only molecular data. Although non-molecular evidence comprised only 3.5% of the total evidence matrix, it had a strong impact on our total evidence results. Only one species group was monophyletic in the molecular-only analysis, and support differed in 86% of the 54 Leptodactylus clades that are shared by the results of the two analyses. Even though no non-molecular evidence was included for Hydrolaetare, exclusion of that data partition resulted in that genus being nested within Leptodactylus, demonstrating that the inclusion of a small amount of non-molecular evidence for a subset of species can alter not only the placement of those species, but also species that were not scored for those data. The evolution of several natural history and reproductive traits is considered in the light of our phylogenic framework. Invasion of rocky outcrops, larval oophagy, and use of underground reproductive chambers are restricted to species of the Leptodactylus fuscus and L. pentadactylus groups. In contrast, larval schooling, larval attendance, and more complex parental care are restricted to the L. latrans and L. melanonotus groups. Construction of foam nests is plesiomorphic in Leptodactylus but their placement varies extensively (e.g., underground chambers, surface of waterbodies, natural or excavated basins). Information on species synonymy, etymology, adult and larval morphology, advertisement call, and geographic distribution is summarized in species accounts for the 30 species of the Leptodactylus fuscus group, 17 species of the L. pentadactylus group, eight species of the L. latrans group, and 17 species of the L. melanonotus group, as well as the three species that are currently unassigned to any species group.Se presenta una filogenia del género Leptodactylus, un ciado neotropical rico en especies, basada en análises combinados de datos moleculares (marcadores nuclear y mitocondriales) y no moleculares (caracteres de la morfología de adultos y larvas así como de comportamiento) se muestrearon > 80% de las 75 especies reconocidas. Los resultados apoyan la monofília de Leptodactylus sensu stricto, con Hydrolaetare como su grupo hermano. La monofília recíproca de Hydrolaetare y Leptodactylus no requiere considerar a Hydrolaetare como un subgénero o sinónimo de Leptodactylus sensu lato. Se reconocen Leptodactylus sensu stricto, Hydrolaetare, Adenomera y Lithodytes como géneros monofiléticos válidos. Los resultados en general resuelven los grupos tradicionalmente reconocidos de Leptodactylus, con excepciones de algunas especies que son reasignadas sin la necesidad de proponer nuevos grupos o alterar significativamente el contenido de los grupos tradicionales. Los cuatro grupos de especies forman una topología pectinada donde el grupo de L. fuscus tiene una posición basal, seguido por el grupo de L. pentadactylus que es el grupo hermano al clado formado por los grupo de L. latrans y L. melanonotus. Se estimó el impacto de los datos no moleculares en los resultados, comparándose los resultados de evidencia total con los de los análises de datos moleculares solamente. Los datos no moleculares representan un 3.5% de la matriz de evidencia total, pero estos datos tuvieron un impacto significativo en los resultados del análisis de evidencia total. En el análisis estrictamente molecular solamente un grupo de especies resultó monofilético, y el apoyo difirió en 86% de los 54 ciados de Leptodactylus compartidos entre los dos análises. A pesar que datos no moleculares no fueron incluidos para Hydrolaetare, la exclusión de evidencia no molecular resultó en el género estar dentro de Leptodactylus, demostrando que la inclusión de evidencia no molecular pequeña para un subgrupo de especies altera no solamente la posición topológica de esas especies, sino tambien de las especies para las cuales dichos datos no fueron codificados. La evolución de patrones de historia natural y reprodución se evalúan en el contexto filogenético. La invasión de afloramientos rocosos y la construción de cámaras de reprodución subterraneas está limitada a los grupos de Leptodactylus fuscus y L. pentadactylus, mientras que la oofagia larval está restringida al grupo de L. pentadactylus. Por otro lado, los cárdumenes larvales, la proteción del cárdumen, y otros comportamientos parentales complejos carecterizan al clado formado por los grupos de especies de L. latrans y L. melanonotus. Los resúmenes de especies incluyen información de sinonimias, etimología, morfología de adultos y larvas, cantos, y distribución geográfica para las 30 especies del grupo de Leptodactylus fuscus, 17 especies del grupo L. pentadactylus, ocho especies del grupo de L. latrans, 17 especies del grupo de L. melanonotus, así como para las tres especies que actualmente no se encuentran asociadas a ninguno de los grupos de especies.Taran Grant was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico Proc. 307001/2011-3 and Fundação de Amparo à Pesquisa do Estado de São Paulo Proc. 2012/10000-5

    Feline immunodeficiency virus infection: plasma, but not peripheral blood mononuclear cell virus titer is influenced by zidovudine and cyclosporine

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    The plasma and peripheral blood mononuclear cell (PBMC) titer of feline immunodeficiency virus (FIV) in experimentally infected cats was assessed following administration of either zidovudine or cyclosporine. Treatments were begun 24 h post infection (p.i.) and continued for 4 weeks. Zidovudine treatment did not prevent establishment of infection with FIV, but plasma virus titers were significantly lower than controls at 2 weeks p.i. This reduction of plasma virus titer by zidovudine was not maintained at subsequent sampling times. Similarly, cyclosporine treatment initially lowered plasma virus titers at 2 weeks p.i., but at 4 weeks p.i. the plasma virus titers in cyclosporine-treated cats were significantly higher than in the untreated group. In the untreated group, plasma virus titers declined rapidly to an undetectable level by 14 weeks p.i. Neither zidovudine or cyclosporine treatment significantly influenced the titer of FIV in PBMCs. In all groups (untreated, zidovudine and cyclosporine) the titers in PBMC were high for the duration of the experiment. The decline in plasma virus titers in immunocompetent cats combined with the effect of cyclosporine on plasma titers strongly suggests that the immune system plays a major role in clearing FIV from plasma. In contrast, it appears that the immune response has little impact on PBMC virus titers. This shows that for complete assessment of antiviral agents, both cell-free and cell-associated virus titers must be examined. We also suggest that the limitation of viral titers in PBMC may be of critical importance in the control of lentiviral infection

    Feline immunodeficiency virus infection: plasma, but not peripheral blood mononuclear cell virus titer is influenced by zidovudine and cyclosporine

    No full text
    The plasma and peripheral blood mononuclear cell (PBMC) titer of feline immunodeficiency virus (FIV) in experimentally infected cats was assessed following administration of either zidovudine or cyclosporine. Treatments were begun 24 h post infection (p.i.) and continued for 4 weeks. Zidovudine treatment did not prevent establishment of infection with FIV, but plasma virus titers were significantly lower than controls at 2 weeks p.i. This reduction of plasma virus titer by zidovudine was not maintained at subsequent sampling times. Similarly, cyclosporine treatment initially lowered plasma virus titers at 2 weeks p.i., but at 4 weeks p.i. the plasma virus titers in cyclosporine-treated cats were significantly higher than in the untreated group. In the untreated group, plasma virus titers declined rapidly to an undetectable level by 14 weeks p.i. Neither zidovudine or cyclosporine treatment significantly influenced the titer of FIV in PBMCs. In all groups (untreated, zidovudine and cyclosporine) the titers in PBMC were high for the duration of the experiment. The decline in plasma virus titers in immunocompetent cats combined with the effect of cyclosporine on plasma titers strongly suggests that the immune system plays a major role in clearing FIV from plasma. In contrast, it appears that the immune response has little impact on PBMC virus titers. This shows that for complete assessment of antiviral agents, both cell-free and cell-associated virus titers must be examined. We also suggest that the limitation of viral titers in PBMC may be of critical importance in the control of lentiviral infection

    Prevalence of musical hallucinations in patients referred for audiometric testing

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    Item does not contain fulltextOBJECTIVE: : To assess the prevalence of musical hallucinations in patients referred for audiometric testing and to analyze associations with age, sex, degree of hearing loss, asymmetrical hearing loss, and tinnitus. METHODS: : Patients referred for audiometric testing underwent a semi-structured interview on tinnitus and musical hallucinations. RESULTS: : Out of 194 patients, most of whom had mild to moderate hearing loss, seven (3.6%) had musical hallucinations. Significant associations were found with female sex and predominant left-sided hearing impairment, but not with age, severity of hearing loss, or tinnitus. CONCLUSION: : This study offers no evidence that age is a risk factor. Musical hallucinations seem to be prevalent in women with predominant left-sided hearing impairment
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