64 research outputs found

    Characterizing the scent and chemical composition of Panthera leo marking fluid using solid-phase microextraction and multidimensional gas chromatography–mass spectrometry-olfactometry

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    Lions (Panthera leo) use chemical signaling to indicate health, reproductive status, and territorial ownership. To date, no study has reported on both scent and composition of marking fluid (MF) from P. leo. The objectives of this study were to: 1) develop a novel method for simultaneous chemical and scent identification of lion MF in its totality (urine + MF), 2) identify characteristic odorants responsible for the overall scent of MF as perceived by human panelists, and 3) compare the existing library of known odorous compounds characterized as eliciting behaviors in animals in order to understand potential functionality in lion behavior. Solid-phase microextraction and simultaneous chemical-sensory analyses with multidimensional gas-chromatography-mass spectrometry-olfactometry improved separating, isolating, and identifying mixed (MF, urine) compounds versus solvent-based extraction and chemical analyses. 2,5-Dimethylpyrazine, 4-methylphenol, and 3-methylcyclopentanone were isolated and identified as the compounds responsible for the characteristic odor of lion MF. Twenty-eight volatile organic compounds (VOCs) emitted from MF were identified, adding a new list of compounds previously unidentified in lion urine. New chemicals were identified in nine compound groups: ketones, aldehydes, amines, alcohols, aromatics, sulfur-containing compounds, phenyls, phenols, and volatile fatty acids. Twenty-three VOCs are known semiochemicals that are implicated in attraction, reproduction, and alarm-signaling behaviors in other species

    Amide-controlled, one-pot synthesis of tri-substituted purines generates structural diversity and analogues with trypanocidal activity

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    Anovel one-pot synthesis of tri-substituted purines and the discovery of purine analogues with trypanocidal activity are reported. The reaction is initiated by a metal-free oxidative coupling of primary alkoxides and diaminopyrimidines with Schiff base formation and subsequent annulation in the presence of large N,N-dimethylamides (e.g.N,N-dimethylpropanamide or larger). This synthetic route is in competition with a reaction previously-reported by our group1, allowing the generation of a combinatorial library of tri-substituted purines by the simple modification of the amide and the alkoxide employed. Among the variety of structures generated, two purine analogues displayed trypanocidal activity against the protozoan parasite Trypanosoma brucei with IC50 , 5 mM, being each of those compounds obtained through each of the synthetic pathways.J.J.D.M. thanks Spanish Ministerio de Economı´a y Competitividad for a Ramon y Cajal Fellowship. A.U.B. thanks MRC IGMM for an academic fellowship. This work was partially supported by Grant SAF2011-30528 to J.A.G.S.

    Avaliação neurológica pelo método Dubowitz em recém-nascidos prematuros com idade corrigida de termo comparada a de nascidos a termo Neonatal neurological assessment by the Dubowitz method in preterm infants at term corrected age compared with term infants

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    OBJETIVO: Comparar a avaliação neurológica de recém-nascidos pré-termo em idade de termo com a de recém-nascidos a termo e verificar a presença de associação entre alterações na avaliação neurológica e características e intercorrências clínicas nos prematuros. MÉTODO: Estudo transversal de 60 nascidos a termo e 30 prematuros do Hospital Estadual Mário Covas, em Santo André (SP), avaliados pelo método Dubowitz. Os pontos de corte da pontuação total foram 30,5 e 26 para comparar recém-nascidos pré-termo e a termo, respectivamente. Os prematuros foram avaliados com idade correspondente ao termo, na 37ª semana, e os do grupo controle, 48 horas após o nascimento. Todos os neonatos foram avaliados pela mesma examinadora, entre as mamadas, nos estágios 4 e 5 de sono e vigília. Para análise estatística, utilizaram-se testes de associação. RESULTADOS: 90% dos nascidos pré-termo não atingiram a pontuação esperada para a idade de termo (p<0,0001), com alterações mais evidentes nas dimensões: tônus, tipo de tônus e movimentos. Dentre os prematuros, 57% não atingiram pontuação total igual ou superior a 26. A sepse neonatal foi a única intercorrência associada de maneira significante, com pontuações abaixo da normalidade em recém-nascidos pré-termo (p=0,009). CONCLUSÃO: Os recém-nascidos pré-termo avaliados com 37 semanas de idade corrigida, quando comparados aos nascidos a termo, apresentaram menor pontuação no exame neurológico e apenas a sepse se associou a alterações neurológicas.<br>OBJECTIVE: To compare neonatal neurological assessment of preterm newborn infants at term corrected age with term infants, and to identify the presence of association between neurologic abnormalities in preterm infants and demographic characteristics and neonatal clinical conditions. METHODS: This cross-sectional study enrolled 60 term and 30 preterm infants born at the Mario Covas State Hospital in Santo André, São Paulo, Brazil. The Dubowitz method was applied to assess neurobehavior. The total score cut-offs of 30.5 and 26 were used to compare respectively preterm and term infants and to analyze the variables related to performance in the preterm group. Preterm newborns were evaluated at 37 post-conceptual weeks and the control group was evaluated 48 hours after birth. All newborns were evaluated by the same neurologist, between feedings and at sleep-awake stages 4 or 5. Statistical analysis was performed by association tests. RESULTS: 90% of the preterm infants did not reach the expected score for term age. Underachievement was seen mainly in the domains of muscle tonus, type of muscle tonus and movements. Among the 30 preterm infants included in the study, 57% did not reach a total score > 26. Sepsis was the only complication significantly associated with neurological impairment (p=0.009). CONCLUSION: Preterm newborn infants at 37 weeks corrected age do not accomplish the neurologic performance of term infants. Sepsis was the only clinical variable associated with neurological disabilities
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