3 resultados para nonshivering thermogenesis (NST)
em Scielo Saúde Pública - SP
Resumo:
A new tick, Amblyomma parkeri, n. sp., is described as a parasite of Coendu sp. from S. Paulo, Brazil. Female holotype, nymph and larva are described (Figs. 2 e 3). The n. sp. differs completly from Koch's species Amblyomma longirostre, the common parasite of the Erethizotidae. Standard data for measures of the female dorsal scutum ixodidae are proposed as follows (fig. 1): PA = Antero-posterior; PB = Postero-basal; PM = Postero-median; TT = Transversal; OO = Inter-ocular; OT= Occulo-transversal; SS = Inter-scapular; CC = Cervical; PT = Postero-transversal; ST = Scapulo-transversal; NPT = Normal to the postero-transversal; NST = Normal to the scapulo-transversal. In the female holotype the standard data are as follows: PA = 2.00 mm; PB = 2.26 mm; PM = 1.10 mm; TT = 2.20 mm; OO = 2.26 mm; SS = 0,84 mm; CC = 0.63 mm; SC = 0.12 mm; NPT = 0.20mm; STN = 0.1 mm. Peritrema 0.80 x 0.42 mm with a narrow postero-internal angle and a large, elongated macula. Coxa I with two short spines and all other coxae with only one shorter spine, shortest in coxa IV. Hypostoma spatulated with formula 3/3. Gnathosoma 1.42 mm long and basis 0.63 mm long by 0.84 greatest wide. Palpi with smoth external surface, 1.00 mm long. Type lot No. 4458 from Cotia, S. Paulo, Brazil; in the acarological collection of the Escola Paulista de Medicina, S. Paulo. Ixodes didelphidis, n. sp., differing from Ixodes loricatus Neumann by the shape of the peritremata (figs. 4 a 5) of the male and female and by the number of the punctations in this organ is described form Didelphidae, Muridae and Cavidae. Twenty eight lots were obtained from Anápolis, Goiás, Brasil, where I. loricatus is subtituded by the n. sp. under description. Comparison with NEUMANN'S types of I. loricatus was possible through the courtesy of Prof. A. BRIZARD from Toulouse, who kindly loaned NEUMANN'S material. Female cotypes N° 40 and male allotype N° 531 in the Collection of Ixodidae of the Oswaldo Cruz Institute.
Resumo:
Flowers of Annonaceae are characterized by fleshy petals, many stamens with hard connective shields and numerous carpels with sessile stigmas often covered by sticky secretions. The petals of many representatives during anthesis form a closed pollination chamber. Protogynous dichogamy with strong scent emissions especially during the pistillate stage is a character of nearly all species. Scent emissions can be enhanced by thermogenesis. The prevailing reproductive system in the family seems to be self-compatibility. The basal genus Anaxagorea besides exhibiting several ancestral morphological characters has also many characters which reappear in other genera. Strong fruit-like scents consisting of fruit-esters and alcohols mainly attract small fruit-beetles (genus Colopterus, Nitidulidae) as pollinators, as well as several other beetles (Curculionidae, Chrysomelidae) and fruit-flies (Drosophilidae), which themselves gnaw on the thick petals or their larvae are petal or ovule predators. The flowers and the thick petals are thus a floral brood substrate for the visitors and the thick petals of Anaxagorea have to be interpreted as an antipredator structure. Another function of the closed thick petals is the production of heat by accumulated starch, which enhances scent emission and provides a warm shelter for the attracted beetles. Insight into floral characters and floral ecology of Anaxagorea, the sister group of the rest of the Annonaceae, is particularly important for understanding functional evolution and diversification of the family as a whole. As beetle pollination (cantharophily) is plesiomorphic in Anaxagorea and in Annonaceae, characters associated with beetle pollination appear imprinted in members of the whole family. Pollination by beetles (cantharophily) is the predominant mode of the majority of species worldwide. Examples are given of diurnal representatives (e.g., Guatteria, Duguetia, Annona) which function on the basis of fruit-imitating flowers attracting mainly fruit-inhabiting nitidulid beetles, as well as nocturnal species (e.g., large-flowered Annona and Duguetia species), which additionally to most of the diurnal species exhibit strong flower warming and provide very thick petal tissues for the voracious dynastid scarab beetles (Dynastinae, Scarabaeidae). Further examples will show that a few Annonaceae have adapted in their pollination also to thrips, flies, cockroaches and even bees. Although this non-beetle pollinated species have adapted in flower structure and scent compounds to their respective insects, they still retain some of the specialized cantharophilous characters of their ancestors.
Resumo:
It is well known that mitochondria are the main site for ATP generation within most tissues. However, mitochondria also participate in a surprising number of alternative activities, including intracellular Ca2+ regulation, thermogenesis and the control of apoptosis. In addition, mitochondria are the main cellular generators of reactive oxygen species, and may trigger necrotic cell death under conditions of oxidative stress. This review concentrates on these alternative mitochondrial functions, and their role in cell physiopathology.