Soil sulfur fractions dynamics and distribution in a tropical grass pasture amended with nitrogen and sulfur fertilizers

Soil sulfur (S) partitioning among the various pools and changes in tropical pasture ecosystems remain poorly understood. Our study aimed to investigate the dynamics and distribution of soil S fractions in an 8-year-old signal grass (Brachiaria decumbens Stapf.) pasture fertilized with nitrogen (N) and S. A factorial combination of two N rates (0 and 600?kg N ha1 y1, as NH4NO3) and two S rates (0 and 60?kg S ha1 y1, as gypsum) were applied to signal grass pastures during 2 y. Cattle grazing was controlled during the experimental period. Organic S was the major S pool found in the tropical pasture soil, and represented 97% to 99% of total S content. Among the organic S fractions, residual S was the most abundant (42% to 67% of total S), followed by ester-bonded S (19% to 42%), and C-bonded S (11% to 19%). Plant-available inorganic SO4-S concentrations were very low, even for the treatments receiving S fertilizers. Low inorganic SO4-S stocks suggest that S losses may play a major role in S dynamics of sandy tropical soils. Nitrogen and S additions affected forage yield, S plant uptake, and organic S fractions in the soil. Among the various soil fractions, residual S showed the greatest changes in response to N and S fertilization. Soil organic S increased in plots fertilized with S following the residual S fraction increment (16.6% to 34.8%). Soils cultivated without N and S fertilization showed a decrease in all soil organic S fractions.

Bryozoan biodiversity in Saint Peter and Saint Paul Archipelago, Brazil

Among the marine invertebrate groups recorded from oceanic islands, bryozoans stand out because they can live and reproduce in suboptimal habitats, which may enhance their dispersal capabilities. This study aimed to update the checklist of bryozoans known from the Saint Peter and Saint Paul Archipelago (ASPSP) and discusses their distribution. During the five expeditions conducted between 2007 and 2009, 22 species were found, of which 16 were new occurrences for the archipelago. The bryozoans were collected from different biotic (algae and invertebrates) and abiotic (rocks, rubble and wrecks) substrata. The bryozoan community in ASPSP includes: eight new and probably endemic species, five species that belong to widespread species complexes, three species known only from the Brazilian coast, two species reported from the Western Atlantic and one species recorded from oceanic islets in the Atlantic. Additionally, three species are widespread in tropical to subtropical waters. Margaretta buski can be highlighted as the most conspicuous and abundant species between 1045 m deep and acts as an "ecosystem engineer".

Variability of rainfall and temperature (1912-2008) parameters measured from Santa Maria (29 degrees 41 ' S, 53 degrees 48 ' W) and their connections with ENSO and solar activity

In this work, we analyze the long term variability of rainfall and temperature (1912-2008) of Santa Maria (29 degrees S, 53 degrees W) and its possible connection with natural influences such as solar activity and ENSO. Temperature and rainfall present similar frequencies as revealed by spectral analyses. This analysis shows a large number of short periods between 2-8 years and periods of 11.8-12.3, 19.1-21.0, and 64.3-82.5 years. The cross correlation for rainfall and temperature versus Southern Oscillation Index (SOI) have higher cross-power around 2-8 yr. Rainfall and temperature versus sunspot number (Rz) showed higher cross-power around the 11-yr solar cycle period. A high and continuous cross correlation was observed for Rz-22 yr versus rainfall and temperature. Furthermore, the power between 22-yr solar cycle and meteorological parameters was higher than that obtained with the 11-yr solar cycle, suggesting that the effect of Hale cycle on climate may be stronger than the Schwabe cycle effect. These results indicate that the variability of rainfall and temperature is closely related to the variation of the Southern Oscillation Index and solar activity, and that the El Nino Southern Oscillation and solar activity probably play an important role in the climate system over Southern Brazil. (C) 2011 Elsevier Ltd. All rights reserved.

Toll-like Receptor 2 Knockout Mice Showed Increased Periapical Lesion Size and Osteoclast Number

Introduction: The aim of this study was to characterize the formation and progression of experimentally induced periapical lesions in TLR2 knockout (TLR2 KO) mice. Methods: Periapical lesions were induced in molars of 28 wild type (WT) and 27 TLR2 KO mice. After 7, 21, and 42 days, the animals were euthanized, and the mandibles were subjected to histotechnical processing. Hematoxylin-eosin-stained sections were examined under conventional light microscopy for the description of pulpal, apical, and periapical features and under fluorescence microscopy for the determination of the periapical lesion size. The subsequent sections were evaluated by tartrate resistant acid phosphatase histoenzymology (osteoclasts), Brown and Brenn staining (bacteria), and immunohistochemistry (RANK, RANKL, and OPG). Data were analyzed by the Mann-Whitney U and Kruskal-Wallis tests (alpha = 0.05), Results: The WT group showed significant differences (P < .05) in the periapical lesion size and the osteoclast number between 7 and 42 days and between 21 and 42 days. In the TLR2 KO group, significant differences (P < .05) in the periapical lesion size and the osteoclast number were found between 7 days and the other periods. There was a significant difference (P < .05) between the 2 types of animal regarding the periapical lesion size, which was larger in the TLR2 KO animals. No significant differences (P > .05) were found between WT and TLR2 KO mice related to the pulpal, apical, and periapical features; bacteria localization; and immunohistochemical results (except for RANK expression). Conclusions: TLR2 KO animals developed larger periapical lesions with a greater number of osteoclasts, indicating the important role of this receptor in the host's immune and inflammatory response to root canal and periradicular infection. (J Endod 2012;38:803-813)

Effects of bovine sperm cryopreservation using different freezing techniques and cryoprotective agents on plasma, acrosomal and mitochondrial membranes

The success of semen cryopreservation is influenced by several factors, such as freezing curves and cryoprotectants. These two factors are of special interest once they may lead to many important physical-chemical changes resulting in different degrees of damage in spermatozoa structure. This experiment was designed to compare the effect of bull semen cryopreservation using two freezing techniques: conventional (CT cooling rate of -0.55 degrees C min-1 and freezing rate of -19.1 degrees C min-1) and automated (AT cooling rate of -0.23 degrees C min-1 and freezing rate of -15 degrees C min-1), performed with different curves, and with three cryoprotectants (glycerol, ethylene glycol and dimethyl formamide) on bovine sperm motility and integrity of plasma, acrosomal and mitochondrial membranes. These variables were simultaneously evaluated using the fluorescence probes propidium iodide, fluorescein-conjugated Pisum sativum agglutinin and MitoTracker Green FM. The effects of freezing techniques, as well as of different cryoprotectants were analysed by the analysis of variance. The means were compared by Fishers test. There were no significant differences between freezing techniques (P > 0.05). Glycerol showed higher percentages of motility, vigour and integrity of plasma, acrosomal and mitochondrial membranes than other two cryoprotectants (P < 0.05). Ethylene glycol preserved higher motility and integrity of plasma and mitochondrial membranes than dimethyl formamide (P < 0.05). Sperm motility with glycerol was 30.67 +/- 1.41% and 30.50 +/- 1.06%, with ethylene glycol was 21.17 +/- 1.66% and 21.67 +/- 1.13% and with dimethyl formamide was 8.33 +/- 0.65% and 9.17 +/- 0.72% to CT and AT curves, respectively. The percentage of spermatozoa with simultaneously intact plasma membrane, intact acrosome and mitochondrial function (IPIAH) was 14.82 +/- 1.49% (CT) and 15.83 +/- 1.26% (AT) to glycerol, 9.20 +/- 1.31% (CT) and 9.92 +/- 1.29% (AT) to ethylene glycol 4.65 +/- 0.93% (CT) and 5.17 +/- 0.87% (AT) to dimethyl formamide. Glycerol provided the best results, although nearly 85% of spermatozoa showed some degree of injury in their membranes, suggesting that further studies are required to improve the results of cryopreservation of bovine semen.

Molluscicidal activity of some marine substances against the snail Biomphalaria glabrata (Mollusca, Planorbidae)

Freshwater snails of the genus Biomphalaria play a major role as intermediate hosts of Schistosoma mansoni, the etiologic agent of schistosomiasis. While Biomphalaria spp. control by molluscicides is one of the main strategies to reduce the snail population in infected areas, there are few effective molluscicides commercially available. Natural products may be considered as potentially useful and safe molluscicides. We have evaluated the molluscicidal activity of 12 extracts from ten marine organisms on adult and embryonic stages of Biomphalaria glabrata. Only extracts of the red algae Liagora farinosa and of the sponge Amphimedon viridis presented molluscicidal activity. Lethal concentration (LC)(50) values obtained were 120 mu g/mL for L. farinosa CH2Cl2 extract (apolar fraction) and 20 mu g/mL for A. viridis extract and halitoxin. The polar alga fraction and halitoxin had no effect on B. glabrata embryos. The algae apolar fraction was active on B. glabrata in all embryonic development stages, with LC50 values for blastulae at 42 mu g/mL, gastrulae at 124 mu g/mL, trochophore at 180 mu g/mL, and veliger at 222 mu g/mL. This is the first report of extracts from marine organisms which presented molluscicidal activity.

Functional characterization and oligomerization of a recombinant xyloglucan-specific endo-beta-1,4-glucanase (GH12) from Aspergillus niveus

Xyloglucan is a major structural polysaccharide of the primary (growing) cell wall of higher plants. It consists of a cellulosic backbone (beta-1,4-linked glucosyl residues) that is frequently substituted with side chains. This report describes Aspergillus nidulans strain A773 recombinant secretion of a dimeric xyloglucan-specific endo-beta-1,4-glucanohydrolase (XegA) cloned from Aspergillus niveus. The ORF of the A. niveus xegA gene is comprised of 714 nucleotides, and encodes a 238 amino acid protein with a calculated molecular weight of 23.5 kDa and isoelectric point of 4.38. The optimal pH and temperature were 6.0 and 60 degrees C, respectively. XegA generated a xyloglucan-oligosaccharides (XGOs) pattern similar to that observed for cellulases from family GH12, i.e., demonstrating that its mode of action includes hydrolysis of the glycosidic linkages between glucosyl residues that are not branched with xylose. In contrast to commercial lichenase, mixed linkage beta-glucan (lichenan) was not digested by XegA, indicating that the enzyme did not cleave glucan beta-1,3 or beta-1,6 bonds. The far-UV CD spectrum of the purified enzyme indicated a protein rich in beta-sheet structures as expected for GH12 xyloglucanases. Thermal unfolding studies displayed two transitions with mid-point temperatures of 51.3 degrees C and 81.3 degrees C respectively, and dynamic light scattering studies indicated that the first transition involves a change in oligomeric state from a dimeric to a monomeric form. Since the enzyme is a predominantly a monomer at 60 degrees C. the enzymatic assays demonstrated that XegA is more active in its monomeric state. (c) 2012 Elsevier B.V. All rights reserved.

Prevalence of long face pattern in brazilian individuals of different ethnic backgrounds

Conclusions: Black individuals had greater prevalence of long face pattern, followed by Brown, White and Yellow individuals. The prevalence of long face pattern was 14.06% in which 13.39% and 0.68% belonged to moderate and severe subtypes, respectively.

Molecular epidemiology of livestock rabies viruses isolated in the northeastern Brazilian states of Paraíba and Pernambuco from 2003 - 2009

Background Limited or no epidemiological information has been reported for rabies viruses (RABVs) isolated from livestock in the northeastern Brazilian states of Paraíba (PB) and Pernambuco (PE). The aim of this study was to clarify the molecular epidemiology of RABVs circulating in livestock, especially cattle, in these areas between 2003 and 2009. Findings Phylogenetic analysis based on 890 nt of the nucleoprotein (N) gene revealed that the 52 livestock-derived RABV isolates characterized here belonged to a single lineage. These isolates clustered with a vampire bat-related RABV lineage previously identified in other states in Brazil; within PB and PE, this lineage was divided between the previously characterized main lineage and a novel sub-lineage. Conclusions The occurrences of livestock rabies in PB and PE originated from vampire bat RABVs, and the causative RABV lineage has been circulating in this area of northeastern Brazil for at least 7 years. This distribution pattern may correlate to that of a vampire bat population isolated by geographic barriers.

A compound heterozygote SLC26A2 mutation resulting in robin sequence, mild limbs shortness, accelerated carpal ossification, and multiple epiphysial dysplasia in two Brazilian sisters. A new intermediate phenotype between diastrophic dysplasia and recessive multiple epiphyseal dysplasia

Mutations in solute carrier family 26 (sulfate transporter), member 2 (SLC26A2) gene result in a spectrum of autosomal recessive chondrodysplasias that range from the mildest recessive form of multiple epiphysial dysplasia (rMED) through the most common diastrophic dysplasia (DTD) to lethal atelosteogenesis type II and achondrogenesis IB. The clinical variability has been ascribed to quantitative effect of mutations of the sulfate transporter activity. Here we describe two Brazilian sisters, born to healthy and non consanguineous parents, with Robin sequence, mild shortening of upper and lower limbs, brachymetacarpalia/tarsalia, additional and accelerated carpal ossification, marked genu valgum, and multiple epiphysial dysplasia. This phenotype was intermediate between DTD and rMED, and both girls have a compound heterozygous mutations for the SLC26A2, a Finnish founder mutation (c.-26?+?2T>C), and R279W. This combination of mutations has been observed in individuals with different phenotypes, including DTD, DTD variant, and rMED. The distinct phenotype of our cases reinforces the hypothesis that other factors may be influencing the phenotype as previously suggested.

Antioxidant activity and chemical composition of the non polar fraction of Gracilaria domingensis (Kützing) Sonder ex Dickie and Gracilaria birdiae (Plastino & Oliveira)

Gracilaria domingensis (Kützing) Sonder ex Dickie and Gracilaria birdiae (Plastino & Oliveira) (Gracilariales, Rhodophyta) are seaweeds that occur on the Brazilian coast. Based on their economic and pharmaceutical importance, we investigated the antioxidant activity of the methanolic, ethyl acetate and hexane extracts of both species. The hexane extracts display a high antioxidant activity and comparative analyses indicated G. birdiae as the most active species. Chemical investigation of these fractions showed several carotenoids and fatty acids, as well as cholesterol and sitosterol derivatives. HPLC-DAD analysis of G. birdiae showed violaxanthin (0.04 μg.mg-1 of dry material), antheraxanthin (5.31 μg.mg-1), aloxanthin (0.09 μg.mg-1), zeaxanthin (0.45 μg.mg-1) and β-carotene (0.37 μg.mg-1) as the major carotenoids. G. domingensis showed a similar carotenoid profile, however, with much lower concentration than G. birdiae. Gas chromatography coupled to mass spectrometry was used to determine other nonpolar compounds of these seaweeds. The main compounds detected in both studied species were the fatty acids 16:0; 18:1 Δ9; 20:3 Δ6,9,12, 20:4 Δ5,8,11,14. We found no specificity of compounds in either species. However, G. birdiae, presented higher contents of carotenoids and arachidonic acid than G. domingensis.

A new species of Cheiriphotis (Amphipoda, Corophiidae) from the southwestern Atlantic Ocean

A new species, Cheiriphotis petronioi sp. nov., is described from the Brazilian coast. This species is recognizable amongst its congeners by the carpus of adult male gnathopod 2 not fused with propodus and the palm acute and uropod 1 of adult males without a group of apical setae between rami. Specimens studied herein were collected between 23º and 34ºS (Brazil - São Paulo and Rio Grande do Sul) from 16 to 38 m depth. An updated key to all species of the genus is provided.

Prevalence of overweight and obesity in elderly people from Vitória-ES, Brazil

The scope of this study was to estimate the prevalence of overweight and obesity and its association with socio-economic status in a sample of non-institutionalized elderly people from Vitória-ES, Brazil. This was a cross-sectional survey with a sample of 882 elderly people aged 60 and over. Obesity and overweight were assessed using the body mass index (BMI) and waist circumference (WC). All subjects answered a personal and socio-demographic questionnaire in relation to age, gender, marital status, physical activity, number of children, chronic diseases and smoking. Associations between categorical variables were tested using chi-square analysis with a 5% significance level. The prevalence of overweight and obesity was high (41.8% and 23.4%, respectively) and 50.7% of the elderly had a substantially increased waist circumference. About 4.3% of the individuals had diabetes, 50.4% had hypertension and 14.9% were found to have both diseases. It was observed that both the BMI and WC were significant associated (p<0.05) with sex, marital status, the presence of diseases and with cigarette smoking.

Changes in phytoplankton composition in response to tides, wind-induced mixing conditions, and freshwater outflows in an urbanised estuarine complex

Recent reports have shown an increase in potentially harmful phytoplankton in Santos bay (Southeastern Brazilian Coast), located in a highly urbanised estuarine complex. Prediction of blooms is, thus, essential but the phytoplankton community structure in very dynamic regions is difficult to determine. In the present work, we discriminate bloom forming microphytoplankton dominance and their relationship to physical and meteorological variables to look for patterns observed in different tides and seasons. Comparing 8 distinct situations, we found five scenarios of dominance that could be related to winds, tides and rainfall: i) Surfers, diatoms occurring during high surf zone energies; ii) Sinkers, represented by larger celled diatoms during spring tide, after periods of high precipitation rates; iii) Opportunistic mixers, composed of chain forming diatoms with small or elongate cells occurring during neap tides; iv) Local mixers, microplanktonic diatoms and dinoflagellates which occurred throughout the 298 sampling stations; and v) Mixotrophic dinoflagellates, after intense estuarine discharges. Results suggest alterations in the temporal patterns for some bloom-forming species, while others appeared in abundances above safe limits for public health. This approach can also illustrate possible impacts of changes in freshwater discharge in highly urbanised estuaries.

Brazilian sandy beach macrofauna production: a review

The state of the art of the studies on the production of Brazilian sandy beach macrofauna was analyzed on the basis of the data available in the literature. For this purpose, the representativeness of the production dataset was examined by latitudinal distribution, degree of exposure and morphodynamic state of beaches, taxonomic groups, and methods employed. A descriptive analysis was, further, made to investigate the trends in production of the more representative taxonomic groups and species of sandy beach macrofauna. A total of 69 macrofauna annual production estimates were obtained for 38 populations from 25 studies carried out between 22º56'S and 32º20'S. Production estimates were restricted to populations on beaches located on the southern and southeastern Brazilian coast. Most of the populations in the dataset inhabit exposed dissipative sandy beaches and are mainly represented by mollusks and crustaceans, with a smaller number of polychaetes. The trends in production among taxonomic groups follow a similar pattern to that observed on beaches throughout the world, with high values for bivalves and decapods. The high turnover rate (P/B ratio) of the latter was due to the presence of several populations of the mole crab Emerita brasiliensis, which can attain high values of productivity, in the dataset. Most of the studies focus on the comparison of production and, especially, of P/B ratio according to life history traits in populations of the same species/taxonomic group. Despite the importance of life history-production studies, other approaches, such as the effect of man-induce disturbances on the macrofauna, should be undertaken in these threatened environments.