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1.
Horm Behav ; 142: 105155, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35334327

RESUMO

Cooperative behaviour, sociality and reproductive suppression in African mole-rats have been extensively studied. Nevertheless, endocrine correlates of some species of social mole-rats have been neglected, and these species may hold the key to understanding the behavioural and physiological complexity that allows the maintenance of social groups in African mole-rats. In this study, we investigated endocrine correlates implicated in the suppression of reproduction and cooperative behaviours, namely glucocorticoids (a stress-related indicator) through faecal glucocorticoid metabolites (fGCMs), plasma testosterone (an indicator of aggression) and plasma prolactin in the Mahali mole-rat (Cryptomys hottentotus mahali) across reproductive classes (breeding females and males, non-breeding females and males) and season (wet and dry). Breeders possessed higher levels of testosterone than non-breeders. In reproductively suppressed non-breeding females, fGCMs were significantly higher than in breeders. Furthermore, an adrenocorticotropic hormone stimulation test (ACTH challenge test) on both male and female non-breeders revealed that female non-breeders show a more significant response to the ACTH challenge than males. At the same time, plasma prolactin levels were equally elevated to similar levels in breeding and non-breeding females. Chronically high levels of prolactin and fGCM are reported to cause reproductive suppression and promote cooperative behaviours in non-breeding animals. Furthermore, there was a negative relationship between plasma prolactin and progesterone in non-breeding females. However, during the wet season, a relaxation of suppression occurs through reduced prolactin which corresponds with elevated levels of plasma progesterone in non-breeding females. Therefore, prolactin is hypothesised to be the primary hormone controlling reproductive suppression and cooperative behaviours in non-breeding females. This study provides new endocrine findings for the maintenance of social suppression in the genus Cryptomys.


Assuntos
Ratos-Toupeira , Prolactina , Hormônio Adrenocorticotrópico , Animais , Feminino , Glucocorticoides , Masculino , Ratos-Toupeira/fisiologia , Progesterona , Reprodução/fisiologia , Testosterona
3.
Epidemiol Infect ; 139(12): 1895-901, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21211103

RESUMO

Non-pharmaceutical interventions (NPI) such as facemasks and intensified hand hygiene may be effective in preventing influenza infections in households. It may be equally important that household members, especially children, can learn to use, maintain and tolerate these measures. We monitored adherence and tolerability of these NPI within a cluster-randomized trial in households with influenza index patients. We recruited 147 participants in 41 households, 39 (95%) out of 41 index patients were children (aged <14 years). In households assigned to wear facemasks, their use peaked on day 4 after symptom onset of the index patient at 73% and at 65% for children and adults, respectively. Mean daily frequency of hand disinfection in households assigned to intensified hand hygiene measures peaked at 7·7 (day 6) for children and at 10·1 (day 5) for adults. The majority of participants reported no problems with mask wearing. Data suggest that usage of NPI can be taught and that measures are well tolerated by adults and even sick children alike.


Assuntos
Desinfecção das Mãos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/prevenção & controle , Máscaras/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Adolescente , Adulto , Berlim/epidemiologia , Criança , Feminino , Humanos , Influenza Humana/epidemiologia , Masculino , Pandemias , Autorrelato
4.
J Nat Prod ; 44(6): 693-5, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7334383

RESUMO

Fifty-four species of plants from 36 genera and 21 families were collected in the mountains and high plains of northern Colorado. Extracts were tested for alkaloids, cytotoxicity, antitumor activity and IP toxicity in mice. A few were tested for insect attractant or deterrent properties. Alkaloids were found in 23 species, 15 showed cytotoxicity, and 27 exhibited IP toxicity. Four extracts showed insect deterrent properties, and three proved to attractant. None of the extracts showed useful antitumor activity. High alkaloid content and/or activity in several of the screens can be used to identify species and genera worthy of detailed phytochemical investigation.


Assuntos
Plantas Medicinais/análise , Alcaloides/análise , Alcaloides/toxicidade , Animais , Antineoplásicos Fitogênicos/análise , Colorado , Inseticidas/análise , Camundongos , Extratos Vegetais/análise
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