Parthenogenetic development of domestic cat oocytes treated with ionomycin, cycloheximide, roscovitine and strontium

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

Morphometric analysis of the intestine of domestic quails (Coturnix coturnix japonica) treated with different levels of dietary calcium

The aim of this study was to perform a morphometric analysis of the various parts of the intestine of the domestic quail. Twenty-four female quails (Coturnix coturnix japonica) aged 37 weeks were used and accommodated in laying cages for 12 weeks. Each group was fed a standardized diet containing different quantities of calcium: 2.0%, 2.5%. 3.0% and 3.5%. The birds were weighed, killed, and samples of 1 cm were collected from the duodenum, jejunum and ileum and submitted to the histological routine. The sections obtained were stained in haematoxylin & eosin (H&E). For morphometric analysis, 30 villi and 30 crypts of each segment of the small intestine were measured in order to determine the height and area of the villi, as well as the depth of the crypts. The results showed that although the integrity of the gastrointestinal tract was maintained in all the birds treated with the different calcium levels, a calcium level of 3.0% showed the most promise, as the levels of 2.0% and 2.5% did not cause any alteration in the intestinal tract. Furthermore, a calcium level of 3.5% led to a significant reduction in the height of the villosities, and in consequence reduced the digestive and absorptive capabilities.

Evolutionary and biogeographic history of the subfamily Neoplecostominae (Siluriformes: Loricariidae)

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

Natural history of the South American water snake Helicops leopardinus (Colubridae : Hydropsini) in the pantanal, Central Brazil

The South American water snake Helicops leopardinus is very abundant in the Pantanal wetlands of Central Brazil. We studied the biology of this species based on specimens collected by local workers in the Paraguay River. Females attained greater body lengths and had larger heads than males, but the latter had longer tails. Helicops leopardinus fed on a wide variety of fishes (70% of the total prey items) and frogs, with fishes of the order Gymnotiformes (33.34%) and frogs of the family Hylidae (23.34%) representing the most common prey items. There was relatively lows diet overlap between the sexes and between juveniles and adults. Mean litter size was 6.6 and ranged from 4-11. The reproductive cycle was seasonal, with birth occurring late in the wet season (simultaneous with the flooding of the Paraguay River), facilitating dispersal of young snakes by floating vegetation. Floating vegetation may be a critical habitat for H. leopardinus, and management plans for their maintenance need to be developed.

Natural history of the coral snake Micrurus Pyrrhocryptus Cope 1862 (Elapidae) from semideciduous forests of western Brazil.

Coral snakes in the genus Micrurus are widely distributed in the Neotropics, with more than 50 species already described in this region. They are primarily ground or leaf litter dwellers, feed on snakes or other elongate vertebrates, and tend to reproduce during the rainy season. We present data on the biology of Micrurus pyrrhocryptus from two semideciduous forests of Mato Grosso do Sul state, western Brazil. Two snake species were consumed: the dipsadid Sibynomorphus lavillai and the typhlopid Typhlops brongersmianus. Sexual dimorphism is marked in M. pyrrhocryptus. with males attaining larger sizes and having longer tails. Activity was concentrated in the wet season, when reproduction occurs. The defensive behavior in this species is similar to that displayed by other Micron's, although less pronounced.

Evolutionary history of Scinax treefrogs on land-bridge islands in south-eastern Brazil

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

Is the evolutionary history of the O-type P element in the saltans and willistoni groups of Drosophila similar to that of the canonical P element?

We studied the occurrence of O-type P elements in at least one species of each subgroup of the saltans group, in order to better understand the phylogenetic relationships among the elements within the saltans group and with those of species belonging to the willistoni group. We found that the O-type subfamily has a patchy distribution within the saltans group (it does not occur in D. neocordata and D. emarginata), low sequence divergence among species of the saltans group as well as in relation to species of the willistoni group, a lower rate of synonymous substitution for coding sequences compared to Adh, and phylogenetic incongruities. These findings suggest that the evolutionary history of the O-type subfamily within the saltans and willistoni groups follows the same model proposed for the canonical subfamily of P elements, i.e., events of horizontal transfer between species of the saltans and willistoni groups.

Natural history of Peucetia flava (Araneae, Oxyopidae): seasonal density fluctuation, phenology and sex ratio on the glandular plant Rhyncanthera dichotoma (Melastomataceae)

The seasonal density fluctuation, phenology and sex ratio of Peucetia flava (Oxyopidae) on Rhyncanthera dichotoma (Melastomataceae) were investigated during a year in a swamp in southeastern Brazil. Peucetia flava displayed an unusual non-seasonal life cycle and the population size varied little over the year. The density of Peucetia spiders increased with the increase in abundance of leaves and number of arthropods adhered to glandular trichomes on R. dichotoma leaves. Our findings suggest that seasonal density fluctuation of Peucetia may be influenced by foraging site availability (i.e. leaves) and prey supply (i.e. arthropods adhering to glandular trichomes). The unusual seasonal stability of P. flava may be related to the type of habitat in which this spider occurs (swamp), because of the constant input of allochthonous resources from the water source, i.e. aquatic insects that migrate to the terrestrial environment.

Induced polarization, resistivity, and self-potential: a case history of contamination evaluation due to landfill leakage

This article compares the efficiency of induced polarization (IP) and resistivity in characterizing a contamination plume due to landfill leakage in a typical tropical environment. The resistivity survey revealed denser electrical current flow that induced lower resistivity values due to the high ionic content. The increased ionic concentration diminished the distance of the ionic charges close to the membrane, causing a decrease in the IP phenomena. In addition, the self-potential (SP) method was used to characterize the preferential flow direction of the area. The SP method proved to be effective at determining the flow direction; it is also fast and economical. In this study, the resistivity results were better correlated with the presence of contamination (lower resistivity) than the IP (lower chargeability) data.

Some segmental structural features of the aortic wall of domestic chicken (Gallus domesticus)

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

Subclinical abnormalities of glucose metabolism in Brazilian women with a history of gestational diabetes mellitus

Background. To evaluate insulin release and insulin sensitivity in women with prior gestational diabetes mellitus (GDM) to gain a better understanding of type 2 diabetes pathogenesis.Methods. GDM women were individually matched for age, body mass index, and waist/hip ratio with those who were normal glucose tolerant in a previous pregnancy (NGT). All women presented with normal glucose tolerance. Twenty pairs were submitted to the oral glucose tolerance test (OGTT) with plasma glucose, insulin, and C-peptide determinations. of the 20 pairs, 18 participated in hyperglycemic (10.0 mmol/l) clamp experiments with frequent plasma glucose and insulin determinations, allowing us to calculate first- and second-phase insulin release and the insulin sensitivity index. GDM and NGT women were compared using Student's t-test, the Mann-Whitney U-test, Friedman's non-parametric test, and the two proportion test for independent groups.Results. GDM women showed higher glycosylated hemoglobin values; at OGTT, they showed late insulin peak with increased plasma insulin levels only during the second hour, and a similar plasma C-peptide response despite a higher plasma glucose curve; during hyperglycemic clamp procedures, they showed similar biphasic insulin release and insulin sensitivity index. Considering that a woman with previous GDM had a defect in insulin release and/or insulin sensitivity, if its magnitude was at least 25% lower than that of the matched NGT woman, 43.8% showed impairment of first-phase insulin release and 55.6% insulin resistance.Conclusions. GDM women showed some degree of glucose intolerance. It is therefore necessary to follow them for a longer time.

Influence of domestic sewage leakage on the collapse of tropical soils

In the studied region, 35% of the soil collapses are related to leakage from sewage ducts. The paper describes the soils from this part of Brazil and a series of laboratory tests undertaken using water and domestic sewage fluid as the wetting agents. It is considered that the presence of soaps and detergents as recorded by the sodium concentration facilitates the densification of the soils and hence has a major effect on the surface settlement/collapse.