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

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

Medical conditions in autism spectrum disorders

Autism spectrum disorder (ASD) is a behaviourally defined syndrome where the etiology and pathophysiology is only partially understood. In a small proportion of children with the condition, a specific medical disorder is identified, but the causal significance in many instances is unclear. Currently, the medical conditions that are best established as probable causes of ASD include Fragile X syndrome, Tuberous Sclerosis and abnormalities of chromosome 15 involving the 15q11-13 region. Various other single gene mutations, genetic syndromes, chromosomal abnormalities and rare de novo copy number variants have been reported as being possibly implicated in etiology, as have several ante and post natal exposures and complications. However, in most instances the evidence base for an association with ASD is very limited and largely derives from case reports or findings from small, highly selected and uncontrolled case series. Not only therefore, is there uncertainty over whether the condition is associated, but the potential basis for the association is very poorly understood. In some cases the medical condition may be a consequence of autism or simply represent an associated feature deriving from an underlying shared etiology. Nevertheless, it is clear that in a growing proportion of individuals potentially causal medical conditions are being identified and clarification of their role in etio-pathogenesis is necessary. Indeed, investigations into the causal mechanisms underlying the association between conditions such as tuberous sclerosis, Fragile X and chromosome 15 abnormalities are beginning to cast light on the molecular and neurobiological pathways involved in the pathophysiology of ASD. It is evident therefore, that much can be learnt from the study of probably causal medical disorders as they represent simpler and more tractable model systems in which to investigate causal mechanisms. Recent advances in genetics, molecular and systems biology and neuroscience now mean that there are unparalleled opportunities to test causal hypotheses and gain fundamental insights into the nature of autism and its development

Halitose: proposta de um protocolo de avaliação Halitosis: an assessment protocol proposal

A Halitose é um sintoma constrangedor com significativo impacto social. Ela afeta milhões de pessoas ao redor do mundo e muitos recursos são investidos em produtos para a melhora do hálito, sem sucesso. O estudo da halitose com uma abordagem científica se justifica, uma vez que a halitose é causa de restrição social, diminui a qualidade de vida e pode ser indicativo da presença de doenças mais graves. OBJETIVO: Elaborar um protocolo de avaliação da halitose com o objetivo de minimizar custos, evitar exames desnecessários e orientar o diagnóstico causal. MÉTODO: O protocolo foi elaborado baseado na literatura e na experiência pessoal dos autores, adotando uma anamnese baseada em evidências. RESULTADO: Existem muitas causas da halitose e a maioria delas está relacionada com a cavidade oral, outras estão relacionadas com doenças otorrinolaringológicas e respiratórias. Doenças gastrointestinais, alterações das funções renais e hepáticas e outras síndromes metabólicas são causas menos freqüentes, porém importantes de halitose. CONCLUSÃO: Existem custos importantes envolvidos no diagnóstico e tratamento da halitose, incluindo consultas ambulatoriais, avaliação de especialistas e exames complementares. Estes custos poderiam ser minimizados adotando uma anamnese baseada em evidências e um organograma para uma investigação clínica racional.<br>Halitosis is an embarrassing symptom with a significant social impact. Halitosis affects millions of people worldwide and many resources are spent annually in products to improve halitus, unsuccessfully. The study of halitosis in a scientific basis is justified once halitosis causes social restriction, decreases life quality and may be an indication of serious diseases. AIM: To elaborate a protocol for halitosis assessment in order to minimize costs, avoid unnecessary tests and provide a guideline for diagnosis. METHODS: The protocol was created based on the literature and on the authors’ personal experiences, adopting an evidence-based anamnesis. RESULTS: There are many causes of halitosis and most of them are related to the oral cavity; others are related to otolaryngologic and respiratory diseases. Gastrointestinal diseases, liver/renal impairment and other metabolic syndromes are less frequent, but also important causes of halitosis. CONCLUSION: There are important costs involved in halitosis assessment and treatment, including medical appointments, specialist assessment, and complementary tests. Such costs would be minimized by adopting a protocol of evidence-based anamnesis and a flowchart for a rational clinical investigation