Molecular phylogeny of the western South Atlantic Sciaenidae based on mitochondrial and nuclear data

Fragments of mitochondrial (COI and rRNA 16S) and nuclear (Tmo-4C4) genes were sequenced to evaluate the phylogenetic relationships among 15 genera of the western South Atlantic Sciaenidae, two freshwater genera and the northwest Pacific Larimichthys crocea.Our results suggest a great diversification for the western Atlantic assemblage; the monophyly of Macrodon, Menticirrhus and Plagioscion genera; the distinctiveness of Bardiella, Stellifer and Ophioscion as belonging to the same clade; the possible existence of two distinct groups in Stellifer; the closer relationship between Lonchurus and Paralonchurus; the non-monophyly of Cynoscion; and the remarkable diversification of Larimus breviceps populations in the Brazilian coast. This is the most comprehensive study evaluating the phylogenetic relationships of the western Atlantic sciaenid and provides a guide for future studies within this family.     

Contribution of genetic distances studies to the taxonomy ofAteles,particularlyAteles paniscus paniscus andAteles paniscus chamek

We studied 20 electrophoretic loci in two populations ofAteles (Ateles paniscus paniscus andAteles paniscus chamek). We observed intrapopulational variation at the following loci: esterase D, glyoxalase 1, adenosine deaminase (A. p. chamek) and carbonic anhydrase 2 (A. p. paniscus). The two populations share the most frequent alleles at 17 loci, but we noted great differences in glyoxalase 1, adenosine deaminase and phosphoglucomutase 1.A. p. paniscus is monomorphic for theGLO1 ^*1 allele, which has a frequency of 6% inA. p.chamek. They did not share alleles in relation to the ADA and PGM1 loci. We found a CA2 allele, named hereCA2 ^*1, which has not been described previously in other neotropical primates (Sampaio et al., 1991a), inA. p. paniscus. The present results suggest that the geographical isolation represented by the Rio Amazonas has lasted long enough to support this level of divergence. These observations taken together with chromosomal findings, led us to endorse the proposal of two distinct species:Ateles paniscus andAteles chamek.     

Identification, tissue distribution and evaluation of brain neuropeptide Y gene expression in the Brazilian flounder Paralichthys orbignyanus

Neuropeptide Y (NPY) is one of the most potent stimulants of food intake in vertebrates, mammals and fish. However, the present knowledge about feeding behaviour in fish is still limited and based on studies in a few species. The Brazilian flounder Paralichthys orbignyanus is being considered for aquaculture, and it is important to understand the mechanisms regulating feeding in order to improve its performance in captivity. The objectives of this study were to clone NPY cDNA, evaluate the mRNA levels in different tissues of flounder, and also evaluate brain NPY expression to associate food intake with NPY expression levels. A 597 bp NPY cDNA was cloned from Brazilian flounder brain. NPY expression was detected in all the peripheral tissues analysed. No significant differences were observed in brain NPY gene expression over 24 h after food intake at a temperature of 15 ± 3°C. No correlation was observed among plasma glucose, total protein, cholesterol, triglycerides and NPY expression levels during this 24 h period. On the other hand, mRNA levels were increased after two weeks of fasting at elevated temperatures. Our results suggest that NPY mRNA levels in Brazilian flounder are affected by temperature.     

The Predominance of Alternatively Activated Macrophages Following Challenge with Cell Wall Peptide-Polysaccharide After Prior Infection with Sporothrix schenckii

Sporotrichosis is a subcutaneous mycosis that is caused by the dimorphic fungus Sporothrix schenckii. This disease generally occurs within the skin and subcutaneous tissues, causing lesions that can spread through adjacent lymphatic vessels and sometimes leading to systemic diseases in immunocompromised patients. Macrophages are crucial for proper immune responses against a variety of pathogens. Furthermore, macrophages can play different roles in response to different microorganisms and forms of activation, and they can be divided into “classic” or “alternatively” activated populations, as also known as M1 and M2 macrophages. M1 cells can lead to tissue injury and contribute to pathogenesis, whereas M2 cells promote angiogenesis, tissue remodeling, and repair. The aim of this study was to investigate the roles of M1 and M2 macrophages in a sporotrichosis model. Toward this end, we performed phenotyping of peritoneal exudate cells and evaluated the concomitant production of several immunomediators, including IL-12, IL-10, TGF-β, nitric oxide, and arginase-I activity, which were stimulated ex vivo with cell wall peptide-polysaccharide. Our results showed the predominance of the M2 macrophage population, indicated by peaks of arginase-I activity as well as IL-10 and TGF-β production during the 6th and 8th weeks after infection. These results were consistent with cellular phenotyping that revealed increases in CD206-positive cells over this period. This is the first report of the participation of M2 macrophages in sporotrichosis infections.     

Proposal for a microcosm biofilm model for the study of vulvovaginal candidiasis

Abstract

This study proposes a microcosm biofilm (MiB) model for the study of vulvovaginal candidiasis (VVC). Different conditions that mimic the vaginal environment were tested for MiB formation. The best growth conditions were obtained with samples incubated in vaginal fluid simulator medium pH 4.5 at 35?°C under a microaerophilic atmosphere. MiBs were evaluated for growth kinetics, fluconazole susceptibility and morphology. Samples containing high numbers of bacteria were analyzed for metagenomics. At 48?h, MiBs presented a higher cell density (CFU ml^?1), a higher biomass and tolerance to fluconazole than their corresponding monospecies biofilms. Morphological analysis of MiBs revealed blastoconidia preferentially adhered to epithelial cells. Abundant Lactobacillus spp. were detected in two clinical samples; their MiBs showed a lower biomass and a higher fluconazole susceptibility. The proposed model proved to be a useful tool for the study of the complex microbial relationship in the vaginal environment, and may help to find new strategies for VVC control.     

Tetrapeptide substrates for the discrimination among kallikreins and other trypsin-like serine proteinases

The three tetrapeptides Ac-Phe-Arg-Arg-Val-NH2 (I), Ac-Phe-Arg-Arg-Pro-NH2 (II) and Ac-Phe-Lys-Arg-Val-NH2 (III) were shown to form a most convenient substrate system for the discrimination of the serine proteinases listed below. Tissue kallikreins (porcine pancreatic, horse and human urinary) have the unique feature of cleaving well the Arg-Arg bond in peptide I (P'2 = Val), hardly splitting it in peptide II (P'2 = Pro). The kcat/Km for the hydrolysis of peptide II by horse urinary kallikrein was 600-fold lower than that for peptide I. Trypsin, plasma kallikreins (human and rat), tonin and rat urinary kallikrein were distinguished from each other by the sequence of the N-terminal fragments formed in the hydrolysis of peptides I and/or II. Differences in the cleavage sites in these peptides are explained by differences in the specificities of the proteinase subsite S2 and/or in their preference for Arg or Lys residues. The three tetrapeptides were not substrates for plasmin.     

Two new species of <Emphasis Type="Italic">Sloanea</Emphasis> (Elaeocarpaceae) from the Brazilian Atlantic Forest

Two new species of Sloanea are described and illustrated: S. fasciculata D. Samp. & V. C. Souza and S. hatschbachii D. Samp. & V. C. Souza. Both species are endemic to the Atlantic Forest states of Espírito Santo and Paraná in Brazil. S. fasciculata is similar to S. hirsuta (Schott) Planch. ex Benth., but has a fasciculate inflorescence and deeply-divided stigma. S. hatschbachii is similar to S. lasiocoma K. Schum. with regard to the morphology of the leaves, flowers and inflorescence, which is a frondose-bracteate raceme, but can be differentiated by the size of the style, the extension of the connective, and the length of the sepals.     

Long-term potential for fires in estimates of the occurrence of savannas in the tropics

Aim   This study aims to improve the formulation and results of the Brazilian Center for Weather Forecasting and Climate Studies Potential Vegetation Model (CPTEC-PVM) by developing a new parameterization for the long-term occurrence of fire in regions of potential savannas in the tropics. Compared with the relatively slow processes of carbon uptake and growth in vegetation, fast mortality and biomass consumption by fires may favour grasses and reduce tree coverage.
Location   The tropics.
Methods   For finding large-scale relationships between fires and other environmental factors, we made two main simplifying assumptions. First, lightning is the most important source of ignition for natural fires. Second, over continental areas in the tropics, lightning is mainly related to the zonal flux of moisture transport.
Results   The parameterization of fire occurrence was built based on a simple empirical relationship, combining information on mean and intra-annual variance of the zonal wind.
Main conclusions   The implementation of this new relationship improved the formulation and the results of the CPTEC-PVM. As a result of this new parameter, the accuracy of the model in allocating the correct vegetation (seasonal forests) instead of savannas for large regions in India and Southeast Asia is now substantially higher than in previous studies.