Validation of TOF-SIMS and FE-SEM/EDS Techniques Combined with Sorption and Desorption Experiments to Check Competitive and Individual Pb2+ and Cd2+ Association with Components of B Soil Horizons

Sorption and desorption experiments were performed by the batch method on the B horizons of five natural soils: Umbric Cambisol, Endoleptic Luvisol, Mollic Umbrisol, Dystric Umbrisol, and Dystric Fluvisol. Individual and competitive sorption and desorption capacity and hysteresis were determined. The results showed that Pb²⁺ was sorbed and retained in a greater quantity than Cd²⁺ and that the hysteresis of the first was greater than that of the second. The most influential characteristics of the sorption and retention of Pb²⁺ were pH, ECEC, Fe and Mn oxides and clay contents. For Cd²⁺ they were mainly pH and, to a lesser extent, Mn oxides and clay content. The combined use of TOF-SIMS, FE-SEM/EDS and sorption and desorption analyses was suitable for achieving a better understanding of the interaction between soil components and the two heavy metals. They show the preferential association of Pb²⁺ with vermiculite, chlorite, Fe and Mn oxides, and of Cd²⁺ with the same components, although to a much lesser extent and intensity. This was due to the latter’s higher mobility as it competed unfavourably with the Pb²⁺ sorption sites. TOF-SIMS and FE-SEM/EDS techniques confirmed the results of the sorption experiments, and also provided valuable information on whether the soil components (individually or in association) retain Cd²⁺ and / or Pb²⁺; this could help to propose effective measures for the remediation of contaminated soils.     

Fragmentation gradients differentially affect the species range distributions of four taxonomic groups in semi‐deciduous Atlantic forest

Human activities often cause habitat fragmentation and how forest fragments affect species range distributions has implications for ecology and conservation. However, few studies have considered communities within the same landscape. Here, we analyzed metacommunity structure to determine the range distributions for species in four taxonomic groups (amphibians, birds, social wasps, and trees) in a patchy landscape of semi‐deciduous Atlantic forest in southwestern Brazil. Although trees are a key component of the environment for animals in forested patches, the ranges of bird, wasp, and amphibian species did not change in concert with the species ranges of trees. The species ranges of amphibians and social wasps were unaffected by fragmentation gradients and exhibited independent distribution patterns (i.e., random structure). In contrast, birds and trees exhibited range turnover along different fragmentation gradients, indicating that species show idiosyncratic responses to abiotic factors (i.e., Gleasonian structure). For birds, some less‐resilient species occurred only in fragments with a large area of native vegetation at a radius of 5 km from the center of the sampled forest fragments, whereas other more stress‐tolerant species occurred only in sites with small areas of native vegetation. For trees, some later succession species (e.g., animal‐dispersed seeds) occurred only in fragments with high connectivity, whereas earlier‐recruiting species (e.g., wind‐dispersed seeds) occurred in fragments with low connectivity. Thus, determining the effects of human‐modified landscapes on species range distributions, even within the same landscape, might not be a trivial task.     

Characterization of new microsatellite loci from Vitis vinifera and their conservation in some Vitis species and hybrids

We present here characterization data for seven new microsatellite markers designed from new microsatellite loci isolated from a microsatellite‐enriched DNA library from Vitis vinifera. The observed heterozygosity varied from 0.73 up to 0.93 and the number of alleles per locus ranged from 12 to 26. This high polymorphism makes these new markers interesting for use in genotyping studies and completing the set of microsatellite markers already available for V. vinifera. Additionally these seven new markers appear to be conserved in four other Vitis species and 15 Vitis hybrids used as rootstocks for V. vinifera cultivation.     

Exercise increases interleukin-10 levels both intraarticularly and peri-synovially in patients with knee osteoarthritis: a randomized controlled trial

Introduction  

The microdialysis method was applied to the human knee joint with osteoarthritis (OA) in order to reveal changes in biochemical markers of cartilage and inflammation, intraarticularly and in the synovium, in response to a single bout of mechanical joint loading.     

Sequence analysis of the growth hormone gene of the South American catfish Rhamdia quelen

Rhamdia quelen is an important Neotropical catfish species for fisheries and aquaculture in southern Brazil, where it is called Jandia. Like other native Brazilian species of economic importance, R. quelen genetics needs more attention for animal breeding programs. The growth hormone gene is known to be linked to a number of molecular markers and quantitative trait loci. We sequenced the coding region of the growth hormone gene with the primer walking technique. As in other Siluriformes, the R. quelen growth hormone gene has four introns and five exons, in a 1465-bp coding region. The tertiary structure of the encoded protein was predicted by bioinformatics; it has four α-helix structures connected by loops, which form a compressed complex maintained by two disulfide bridges.     

Molecular insights into human monoamine oxidase (MAO) inhibition by 1,4-naphthoquinone: evidences for menadione (vitamin K3) acting as a competitive and reversible inhibitor of MAO

Monoamine oxidase (MAO) catalyzes the oxidative deamination of biogenic and exogenous amines and its inhibitors have therapeutic value for several conditions including affective disorders, stroke, neurodegenerative diseases and aging. The discovery of 2,3,6-trimethyl-1,4-naphthoquinone (TMN) as a nonselective and reversible inhibitor of MAO, has suggested 1,4-naphthoquinone (1,4-NQ) as a potential scaffold for designing new MAO inhibitors. Combining molecular modeling tools and biochemical assays we evaluate the kinetic and molecular details of the inhibition of human MAO by 1,4-NQ, comparing it with TMN and menadione. Menadione (2-methyl-1,4-naphthoquinone) is a multitarget drug that acts as a precursor of vitamin K and an inducer of mitochondrial permeability transition. Herein we show that MAO-B was inhibited competitively by 1,4-NQ (K_i = 1.4 μM) whereas MAO-A was inhibited by non-competitive mechanism (K_i = 7.7 μM). Contrasting with TMN and 1,4-NQ, menadione exhibited a 60-fold selectivity for MAO-B (K_i = 0.4 μM) in comparison with MAO-A (K_i = 26 μM), which makes it as selective as rasagiline. Fluorescence and molecular modeling data indicated that these inhibitors interact with the flavin moiety at the active site of the enzyme. Additionally, docking studies suggest the phenyl side groups of Tyr407 and Tyr444 (for MAO-A) or Tyr398 and Tyr435 (for MAO-B) play an important role in the interaction of the enzyme with 1,4-NQ scaffold through forces of dispersion as verified for menadione, TMN and 1,4-NQ. Taken together, our findings reveal the molecular details of MAO inhibition by 1,4-NQ scaffold and show for the first time that menadione acts as a competitive and reversible inhibitor of human MAO.     

Genetic damage in exfoliated cells from oral mucosa of individuals exposed to X-rays during panoramic dental radiographies

The genotoxic effects of X-ray emitted during dental panoramic radiography were evaluated in exfoliated cells from oral epithelium through a differentiated protocol of the micronucleus test. Thirty-one healthy individuals agreed to participate in this study and were submitted to this procedure for diagnosis purpose after being requested by the dentist. All of them answered a questionnaire before the examination. Cells were obtained from both sides of the cheek by gentle scrapping with a cervical brush, immediately before the exposure and after 10 days. Cytological preparations were stained according to Feulgen-Rossenbeck reaction and analyzed under light and laser scanning confocal microscopies. Micronuclei, nuclear projections (buds and broken eggs) and degenerative nuclear alterations (condensed chromatin, karyolysis and karyorrhexis) were scored. The frequencies of micronuclei, karyolysis and pycnosis were similar before and after exposure (P > 0.90), whereas the condensation of the chromatin and the karyorrhexis increased significantly after exposure (P < 0.0001). In contrast, both bud and broken egg frequencies were significantly higher before the examination (P < 0.005), suggesting that these structures are associated to the normal epithelium differentiation. The results suggest that the X-ray exposure during panoramic dental radiography induces a cytotoxic effect by increasing apoptosis. We also believe that the score of other nuclear alterations in addition to the micronucleus improves the sensitivity of genotoxic effects detection.     

Identification of Toxigenic Fusarium Species using PCR Assays

Isolates of the toxigenic cereal pathogens Fusarium culmorum, Fusarium graminearum, Fusarium crookwellense and Fusarium avenaceum, from Poland (48 isolates) and 12 from England, New Zealand, Italy and Canada, were examined using random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR), sequence-characterized amplified regions (SCARs), morphology and mycotoxin production under laboratory conditions. Their DNA products were compared by RAPD-PCR, which showed species-specific bands and the greatest diversity among isolates of F. avenaceum. PCR using three 20-mer-primer-pairs that are reported to be useful for identification of F. culmorum and F. graminearum group 2 confirmed their species-specificity. The same species-specific PCR product was observed in isolates of both nivalenol and deoxynivalenol chemotypes of F. culmorum or F. graminearum. A clear relationship was found between morphological and species-specific PCR identification of F. culmorum and F. graminearum isolates. However, F. avenaceum can be confused when using primers FA-ITS F/R (SCAR 2-14) with Fusarium tricinctum because the same band 272 bp appears in the gel, in both species probes.