Changes in iodine mapping in rat thyroid during the course of iodine deficiency: imaging and relative quantitation by analytical ion microscope

The analytical ion microscope (AIM) makes possible imaging and relative quantitation of multiple stable or labeled elements on an even tissue section, according to their mass. The purpose of this work was to follow at the rat thyroid follicle level the changes in 127I mapping during low iodine diet (LID) in relation to the ability of thyroid to pick up radioiodine (129I) and to synthesize Tg from its precursor, 2H-labeled leucine. The overall picture of images and countings of 127I shows a progressive decrease of the luminal iodine concentration which on day 80 was 10-fold lower than that of control value. In control rat thyroid cell, concentration was 10-fold lower than that of follicular lumina and was unchanged until 35 days, but the size of the cytoplasmic compartment increased, suggesting a redistribution of iodine stores between thyroid cells and follicular lumina. 129I was always found in colloid as well as in cells at all stages. After 35 days of LID, cytoplasmic and luminal radioiodine concentrations decreased. In control rats, [2H]leucine was found mainly in the cells. During LID its localization was evidenced progressively in most of the lumina. The most striking fact was the presence up to 35 days of some large residual follicles with high 127I concentration and low 129I and 2H incorporation. These data demonstrate the follicular heterogeneity of thyroid response to progressive chronic TSH stimulation induced by LID.     

Non-Lévy Mobility Patterns of Mexican Me’Phaa Peasants Searching for Fuel Wood

We measured mobility patterns that describe walking trajectories of individual Me’Phaa peasants searching for and collecting fuel wood in the forests of “La Monta?a de Guerrero” in Mexico. These 1-day excursions typically follow a mixed pattern of nearly-constant steps when individuals displace from their homes towards potential collecting sites and a mixed pattern of steps of different lengths when actually searching for fallen wood in the forest. Displacements in the searching phase seem not to be compatible with Lévy flights described by power-laws with optimal scaling exponents. These findings, however, can be interpreted in the light of deterministic searching on heavily degraded landscapes where the interaction of the individuals with their fuel wood-scarce environment produces alternative searching strategies than the expected Lévy flights. These results have important implications for future management and restoration of degraded forests and the improvement of the ecological services they may provide to their inhabitants.     

Plasmodium simium/Plasmodium vivax infections in southern brown howler monkeys from the Atlantic Forest

Blood infection by the simian parasite, Plasmodium simium, was identified in captive (n = 45, 4.4%) and in wild Alouatta clamitans monkeys (n = 20, 35%) from the Atlantic Forest of southern Brazil. A single malaria infection was symptomatic and the monkey presented clinical and haematological alterations. A high frequency of Plasmodium vivax-specific antibodies was detected among these monkeys, with 87% of the monkeys testing positive against P. vivax antigens. These findings highlight the possibility of malaria as a zoonosis in the remaining Atlantic Forest and its impact on the epidemiology of the disease.     

Sur quelques zooplanctontes abondants dans l'upwelling de Cabo Frio (Bresil)

On some zooplankters common in the Cabo Frio (Brazil) upwelling.In the waters off Cabo Frio zooplankton maxima are observedbetween February and April, which is the period of upwellingoccurrence. Copepods are highly diversified; we identified 96species at a single collecting station during one year. In summerCalanoides carinatus, Paracalanus parvus and Oncea media areabundant, whereas we observed dominance of Temora stylifera,Clausocalanus furcatus, C. arcuicomis, Oithona plumifera andgreat quantity of Creseis acicula during winter. Chaetognatha(Sagitta enflata), Appendicularia (Oikopleura longicauda), Ostracoda(Conchoecia spp.) and Pteropoda (Limacina sp.) are permanentthroughout the year, and maximum in summer. The vertical distributionof zooplankton depends on the hydrological structure, i.e. natureof the water mass and degree of mixing between different waters.Brazil current water, with low quantity of organisms and dominanceof copepods (Clausocalanus furcatus, Mecynocera clausi, Corycaeidae,Oithonidae, Oncaeidae) accompanied by Evadne spinifera and Lucifertypicus. South Atlantic Central Water (upwelling water) characterizedby rare deep copepods and abundance of Calanoides carinatusand Ctenocalanus vanus which are excellent indicator speciesfor upwelling occurrence. Coastal water, with low salinity,where some species with brackish affinity are observed, likeOithona ovalis and Podon polyphemoides.     

Chapmannia floridana Torrey & Gray (Fabaceae)

Chapmannia Torrey & Gray, a monotypic legume genus of Florida, is shown to have perfect flowers, rather than sterile and fertile flowers incorrectly attributed to the genus by authors for the past one hundred years. The species is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny and cytology.     

Pachecoa prismatica (Fabaceae): Taxonomy and phylogeny

Pachecoa Standley & Steyerm., a monotypic legume genus of Mexico, Guatemala, and Venezuela, is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny, cytology, and relationship (with key) to allied genera.     

Seasonal variation of energy metabolism in ghost crab Ocypode quadrata at Siriú Beach (Brazil)

The aim of this study was to analyze the seasonal variations of carbohydrate and lipid metabolism of the ghost crab Ocypode quadrata (Fabricius, 1787) on a sandy beach in the southern region of Brazil. Crabs and hemolymph samples were collected monthly in the field. Hepatopancreas, gills, gonads and claw muscles were used for glycogen determination. In males, blood glucose levels increased in the summer and in the winter. The glycogen values increased significantly in the hepatopancreas in the winter, but remained constant in the muscle, gonads and gills. In females, hemolymph glucose levels, glycogen values in the hepatopancreas and in the gills remained constant throughout the year; however, muscular glycogen increased in the spring and gonad glycogen decreased in the summer. Hemolymph triglyceride levels of males and females and total cholesterol of males decreased significantly in the spring. In females, a significant increase of total cholesterol levels was found in the winter. The findings suggest that in O. quadrata lipids seem to be an important reserve of energy used during reproduction, both in males and females, while glycogen may be used during periods of intense activity or fasting.