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1.
Hum Exp Toxicol ; 33(5): 517-21, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23928831

RESUMO

In this randomized parallel study, we examined whether an acute ozone (O3) exposure leads to increased DNA strand breaks in human lymphocytes. The groups were exposed to 0.21 ppm O3 or filtered air for two hours. 30min and 4.5 h after exposure, DNA damage was determined in isolated lymphocytes using the Fast Micromethod. There was no detectable effect after O3 exposure. We conclude that an acute O3 exposure at the tested concentration does not lead to persistent DNA damage.


Assuntos
Dano ao DNA , DNA de Cadeia Simples/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Ozônio/toxicidade , Humanos , Linfócitos/metabolismo
2.
Nat Commun ; 5: 4747, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25158760

RESUMO

Proactive, that is, unsolicited, prosociality is a key component of our hyper-cooperation, which in turn has enabled the emergence of various uniquely human traits, including complex cognition, morality and cumulative culture and technology. However, the evolutionary foundation of the human prosocial sentiment remains poorly understood, largely because primate data from numerous, often incommensurable testing paradigms do not provide an adequate basis for formal tests of the various functional hypotheses. We therefore present the results of standardized prosociality experiments in 24 groups of 15 primate species, including humans. Extensive allomaternal care is by far the best predictor of interspecific variation in proactive prosociality. Proactive prosocial motivations therefore systematically arise whenever selection favours the evolution of cooperative breeding. Because the human data fit this general primate pattern, the adoption of cooperative breeding by our hominin ancestors also provides the most parsimonious explanation for the origin of human hyper-cooperation.


Assuntos
Comportamento Animal , Evolução Biológica , Comportamento Cooperativo , Primatas , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Motivação , Experimentação Humana não Terapêutica , Primatas/psicologia
3.
Theriogenology ; 77(6): 1088-99, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22192399

RESUMO

Understanding the complex endocrine interactions that control reproduction in felids is essential for captive breeding management. The most important demand is a quick and reliable pregnancy diagnosis. However, the occurrence of pseudopregnancies in felids complicates matters. We investigated whether the fecal prostaglandin metabolite (PGFM) recently suggested for pregnancy diagnosis in the lynx is suitable for all felid species. We found that increased levels of PGFM during the last trimester indicate pregnancy in seven of the eight main lineages of the carnivore family Felidae. PGFM levels in a sand cat (domestic cat lineage) were basal at mating and remained so until Day 40 post-mating. Day 41 marked the beginning of a distinct increase culminating in peak levels of 6.5 µg/g before parturition and decreasing again to baseline thereafter. Similar pregnancy profiles were obtained from the domestic cat, the leopard cat, the lynx, the ocelot and the caracal lineage, whereas in pseudopregnant individuals (sand cat, Iberian and Eurasian lynx) fecal PGFM remained at basal levels. In pregnant cheetahs (puma lineage) PGFM increased above basal following day ∼48 peaking before pregnancy but remained at baseline in pseudopregnant females. Discrepancies existed in the Panthera lineage. While Chinese leopard, Sumatran tiger, and the black panther showed marked increases of PGFM during the last weeks of pregnancy, only moderate increases in PGFM levels were found in the Indochinese tiger and the Persian leopard. Altogether, PGFM as tool for pregnancy diagnosis has been proven to be useful in breeding management of felids.


Assuntos
Biomarcadores/metabolismo , Dinoprosta/análogos & derivados , Felidae/metabolismo , Testes de Gravidez/veterinária , Animais , Cruzamento , Dinoprosta/metabolismo , Espécies em Perigo de Extinção , Fezes/química , Feminino , Gravidez
4.
Theriogenology ; 73(4): 530-40, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20022361

RESUMO

In mammals, uterine and placental prostaglandin F(2alpha) is involved in the regulation of reproduction-related processes such as embryonic development, initiation of parturition, and resumption of ovarian activity. Prostaglandin F(2alpha) (PGF(2alpha)) is rapidly metabolized to its plasma metabolite PGFM (13,14-dihydro-15-keto-PGF(2alpha)), which has also been detected in urine. Therefore, the current study aimed to develop and validate an efficient, quick, and inexpensive enzyme immunoassay (EIA) for PGFM estimation in urine of the Iberian lynx (Lynx pardinus) for pregnancy monitoring and for differentiation between pregnancy and pseudo-pregnancy. Urine samples collected from captive Iberian lynx (11 pregnant and 4 pseudo-pregnant cycles) were subjected directly to a PGFM EIA. The assay was validated for parallelism, precision, and stability of urinary PGFM. In addition, high-performance liquid chromatography (HPLC) immunograms and liquid chromatography-mass spectrometry (LCMS) were performed to identify PGFM within urine samples. Urinary PGFM levels before mating and after parturition were about 1.5 ng/mL. After Day 20 postmating, both pregnant and pseudo-pregnant females showed slight increase of hormone levels; in pseudo-pregnant females, this elevation did not exceed 7 ng/mL. A significant increase in pregnant females was observed after Day 45 postmating; urinary PGFM increased from 10 ng/mL at Day 45 toward a peak of 46.0+/-19.3 ng/mL around parturition. First results show that PGFM is detectable in feces as well and follows similar courses as shown for urine. In conclusion, the presented and validated PGFM assay is an easy and reliable method for noninvasive pregnancy diagnosis in the Iberian lynx (and probably other felids) if applied approximately 20 d prior parturition in pure urine or fecal extracts. High PGFM levels in urine or fecal samples may allow a pregnancy diagnosis without knowledge of mating time, making the PGFM test applicable to free-ranging animals.


Assuntos
Conservação dos Recursos Naturais/métodos , Dinoprosta/análogos & derivados , Técnicas Imunoenzimáticas/veterinária , Lynx/urina , Prenhez/urina , Animais , Biomarcadores/urina , Dinoprosta/urina , Fezes/química , Feminino , Técnicas Imunoenzimáticas/métodos , Gravidez , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
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