Spawning failure in Brycon amazonicus may be associated with ovulation and not with final oocyte maturation

Avaliaram-se os possíveis mecanismos envolvidos com a falha na desova de matrinxãs (Brycon amazonicus), submetidas à indução hormonal por extrato bruto de hipófise de carpa. Para tal, após a extrusão, os ovários foram coletados e analisados histomorfometricamente. Nas fêmeas que não desovaram (FNDs), a maioria dos ovócitos vitelogênicos remanescentes nos ovários atingiu a maturação final, apresentando quebra de vesícula germinativa, mas não foram ovulados (NOs). Consequentemente, estas fêmeas apresentaram frequências mais baixas de folículos pós ovulatórios (5%) quando comparadas com a que desovou (FD) (23%). Com relação aos NOs, os valores se inverteram e a frequência destes nas FNDs (21%) foi maior do que na FD (3%). Estes dados indicam que as falhas na desova desta espécie estão provavelmente relacionadas com a ovulação, uma vez que a maturação final dos ovócitos ocorre de forma similar tanto nas FNDs como na FD. Os dados sugerem que as substâncias que promovem a ovulação, como as prostaglandinas, podem aumentar o sucesso de desova em peixes reofílicos.

The administration of exogenous prostaglandin may improve ovulation in pacu (Piaractus mesopotamicus)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pycnoscelus surinamensis (Linnaeus, 1758) (Blaberoidea: Blaberidae), a cockroach with a possible association with the ant Brachymyrmex cordemoyi Forel, 1895 (Hymenoptera: Formicidae) and which may be exhibiting a domiciliation trend.

In the present paper, we report on the occurrence of the cockroach Pycnoscelus surinamensis (Linnaeus, 1758) in Brachymyrmex cordemoyi Forel, 1895 nests, indicating a possible symbiosis between these two species. Also, the finding of intradomicile P. surinamensis nymphs may indicate this species is extending its habitat to human habitations, i.e. changing its ecological category from peridomestic to domestic.

The intravenous glucose tolerance and postprandial glucose tests may present different responses in the evaluation of obese dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dietary components may prevent mutation-related diseases in humans

Since it is not always possible to reduce human exposure to mutagens, attempts have been directed to identify potential antimutagens and anticarcinogens for use in protecting the population against environmental disease. The purpose of this paper is to provide the reader with information about the antimutagenic and anticarcinogenic potentials of some dietary constituents and foods widely consumed in Brazil, and to reinforce diet as a key factor in determining genomic stability and preventing human diseases. In this report, we have summarized data that show interactive effects between some dietary components and specific chemical mutagens or carcinogens using in vitro and in vivo short- or medium-term assays. The summary indicates that certain dietary compounds may be useful agents for disease prevention. (C) 2003 Elsevier B.V. All rights reserved.

Root, shoot and leaf traits of the congeneric Styrax species may explain their distribution patterns in the cerrado sensu lato areas in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anaerobic capacity may not be determined by critical power model in elite table tennis players

The aim of the present study was to verify the applicability of anaerobic work capacity (AWC) determined from the critical power model in elite table tennis players. Eight male international level table tennis players participated in the study. The tests undertaken were: 1) A critical frequency test used to determinate the anaerobic work capacity; 2) Wingate tests were performed using leg and arm ergometers. AWC corresponded to 99.5 +/- 29.1 table tennis balls. AWC was not related to peak (r = -0.25), mean (r = -0.02), relative peak (r = -0.49) or relative mean power (r = 0.01), nor fatigue index (r = -0.52) (Wingate leg ergometer). Similar correlations for peak (r = -0.34), mean (r = -0.04), relative peak (r = -0.49), relative mean power (r = -0.14) and peak blood lactate concentration (r = -0.08) were determined in the Wingate arm ergometer test. Based on these results the AWC determined by a modified critical power test was not a good index for measurement of anaerobic capacity in table tennis players.

How may confinement affect technicolour?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Apoptotic bone cells may be engulfed by osteoclasts during alveolar bone resorption in young rats

The alveolar bone is a suitable in vivo physiological model for the study of apoptosis and interactions of bone cells because it undergoes continuous, rapid and intense resorption/remodelling, during a long period of time, to accommodate the growing tooth germs. The intensity of alveolar bone resorption greatly enhances the chances of observing images of the extremely rapid events of apoptosis of bone cells and also of images of interactions between osteoclasts and osteocytes/osteoblasts/bone lining cells. To find such images, we have therefore examined the alveolar bone of young rats using light microscopy, the TUNEL method for apoptosis, and electron microscopy. Fragments of alveolar bone from young rats were fixed in Bouin and formaldehyde for morphology and for the TUNEL method. Glutaraldehyde-formaldehyde fixed specimens were processed for transmission electron microscopy. Results showed TUNEL positive round/ovoid structures on the bone surface and inside osteocytic lacunae. These structures - also stained by hematoxylin - were therefore interpreted, respectively, as osteoblasts/lining cells and osteocytes undergoing apoptosis. Osteoclasts also exhibited TUNEL positive apoptotic bodies inside large vacuoles; the nuclei of osteoclasts, however, were always TUNEL negative. Ultrathin sections revealed typical apoptotic images - round/ovoid bodies with dense crescent-like chromatin - on the bone surface, corresponding therefore to apoptotic osteoblasts/lining cells. Osteocytes also showed images compatible with apoptosis. Large osteoclast vacuoles often contained fragmented cellular material. Our results provide further support for the idea that osteoclasts internalize dying bone cells; we were however, unable to find images of osteoclasts in apoptosis. (C) 2001 Harcourt Publishers Ltd.

Conventional (MG-BR46 Conquista) and Transgenic (BRS Valiosa RR) Soybeans Have No Mutagenic Effects and May Protect Against Induced-DNA Damage In Vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Permanent Genetic Resources added to Molecular Ecology Resources Database 1 May 2009-31 July 2009

This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.