Electroencephalographic Responses to a Noxious Surgical Stimulus in Mules,Horses, and Ponies

The aim of this study was to investigate the electroencephalographic (EEG) response of equidae to a castration stimulus. Study 1 included 11 mules (2½–8 years; 230–315 kg) and 11 horses (1½–3½ years; 315–480 kg); study 2 included four ponies (15–17 months; 176–229 kg). They were castrated under halothane anesthesia after acepromazine premedication (IV [study 1] and intramuscular [study 2]) and thiopental anesthetic induction. Animals were castrated using a semiclosed technique (study 1) and a closed technique (study 2). Raw EEG data were analyzed and the EEG variables, median frequency (F50), total power (Ptot), and spectral edge frequency (F95), were derived using standard techniques at skin incision (skin) and emasculation (emasc) time points. Baseline values of F50, Ptot, and F95 for each animal were used to calculate percentage change from baseline at skin incision and emasculation. Differences were observed in Ptot and F50 data between hemispheres in horses but not mules (study 1) and in one pony (study 2). A response to castration (>10% change relative to baseline) was observed in eight horses (73% of animals) and four mules (36% of animals) for F50 and nine horses (82%) and four mules (36%) for Ptot. No changes in F95 data were observed in any animal in study 1. Responses to castration were observed in three ponies (75% of animals) for F50, one pony (25%) for F95, and all ponies for Ptot. Alteration of acepromazine administration and castration technique produced a protocol that identified changes in EEG frequency and power in response to castration.     

Kinetic study of the oxidation of quercetin by mushroom tyrosinase

The kinetic behavior of mushroom tyrosinase in the presence of the flavonol quercetin was studied. This flavonol was oxidized by mushroom tyrosinase and the reaction was followed by recording spectral changes over time. The spectra obtained during the reaction showed two isosbectic points, indicating a stable o-quinone. When quercetin was oxidized by tyrosinase in the presence of cysteine and 3-methyl-2-benzothiazolone hydrazone (Besthorn's hydrazone, MBTH) isosbestic points were also observed indicating a definite stoichiometry. From the data analysis of the initial rate in the presence of MBTH, the kinetic parameters: = (16.2 +/- 0.6) microM/min, = (0.12 +/- 0.01) mM, (/) = (V(max)/K(S)(')()) = (13.5 +/- 1.4) x 10(-)(2) min(-)(1), = (6.2 +/- 0.6) s(-)(1) were determined. We propose that quercetin acts simultaneously as a substrate and a rapid reversible inhibitor of mushroom tyrosinase, depending on how it binds to the copper atom of the enzyme active site. Thus, if the binding occurs through the hydroxylic groups at the C3' and C4' positions, quercetin acts as a substrate, while if it occurs through the hydroxylic group at the C3 position of the pyrone ring, quercetin acts as an inhibitor.     

At which spatial scale are plant species composition and diversity affected in beech forests?

• Context  

Landscape structure is crucial for forest conservation in regions where the natural forest is fragmented. Practical conservation is currently shifting from local stands to a landscape perspective, although few studies have tested the relative effects of different spatial scales on plant species composition and diversity in forests.     

Potential synergistic effect of Melia azedarach fruit extract and Beauveria bassiana in the control of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) in cattle infestations

The use of a concentrate emulsion of Melia azedarach green fruits and a suspension of the fungus Beauveria bassiana was evaluated in the control of Rhipicephalus microplus on artificially infested cattle. The evaluation was conducted following the protocol established by the Brazilian Agriculture Ministry. Five groups of 4 or 5 animals were allocated to one of the following treatments: emulsion concentrate of M. azedarach at 0.25% (T AZED 0.25%), emulsion concentrate of M. azedarach at 0.5% (T AZED 0.5%), B. bassiana at 2.4 × 10(8) conidia (T BASS), association of the concentrate of M. azedarach at 0.25% with B. bassiana at 2.4 × 10(8) conidia (T AZED 0.25%+BASS), and control (untreated). The association of the two compounds provided better results than any one isolated treatment, indicating compatibility or perhaps a synergy between M. azedarach and B. bassiana. This treatment resulted in fewer engorged females (129 ± 70) than in the control group (233 ± 82), showing high performance against all developmental stages of the tick. Results revealed an apparent synergistic effect of M. azedarach and B. bassiana in the control of R. microplus that should be further investigated.     

Canine testicular tumors in descended and cryptorchid testes

A comparative study of canine testicular tumors in descended and cryptorchid testes was performed in order to associate pathologic features with clinical signs. Observation on 80 canine testicular tumors revealed the following distribution: in undescended testes, 4 tumors were classified as Seminomas (mean age: 8.8 +/- 3 years) and 14 as Sertoli cell tumors (8.7 +/- 1.7 years); in descended testes, 21 tumors were classified as seminomas (8.8 +/- 3 years), 13 as Sertoli cell tumors (9.8 +/- 1.8 years), 22 as Leydig cell tumors (11.5 +/- 2 years), 5 multiple primary tumors and 1 as an immunoblastic lymphoma. Histological features were studied and correlated with other clinical parameters: feminization manifestations, prostatic disease, perineal hernia and perianal gland tumor.     

Bacterial community structure and detection of putative plant growth-promoting rhizobacteria associated with plants grown in Chilean agro-ecosystems and undisturbed ecosystems

Soil microorganisms with phytase- and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activities are widely studied as plant growth-promoting rhizobacteria (PGPR). Here, we explored the bacterial community structure and occurrence of putative PGPR in plants grown in agro-ecosystems and undisturbed ecosystems from northern, central, and southern Chile. Total rhizobacterial community structure was evaluated by denaturing gradient gel electrophoresis, and dominant bands present in diverse ecosystems were sequenced. Significant differences in total bacterial communities were shown with some bacterial orders (Enterobacteriales, Actinomycetales, and Rhizobiales) being highly similar to both ecosystems. Twenty-nine putative PGPR, showing phytate- and ACC-degrading activities and production of auxin, were selected from across the sites. Based on 16S rRNA gene sequencing, the putative PGPR were characterized as Enterobacteriales (Enterobacter, Serratia, Pantoea, Rahnella, Leclercia), Pseudomonas, and Bacillus, consistent with previously reported PGPR and endophytic bacteria. Beta-propeller phytase genes with similarity to Bacillus were also identified. PGPR from agro-ecosystems appeared to show higher auxin production compared to those from undisturbed ecosystems. This study demonstrates that putative PGPR are widely distributed across Chilean soils. Further understanding of their contribution to the growth and adaptation of plant hosts to local soil conditions may provide opportunity for development of new PGPR in Chilean agriculture.     

Bacterial community structures in rhizosphere microsites of ryegrass (Lolium perenne var. Nui) as revealed by pyrosequencing

Management of soils to facilitate plant beneficial microbial interactions requires basic knowledge of the species composition and microbial community structures in the plant rhizosphere. Here, we examined composition of bacterial communities associated with rhizosphere microsites located at the root tips and mature root zones of Lolium perenne when grown in Chilean ash-derived volcanic soils (Andisols: Freire and Piedras Negras soil series). Community structures were analyzed by pyrosequencing of 16S ribosomal RNA (rRNA) genes followed by in silico analysis for phylogenetic assignments (MOTHUR and Visualization tool for Taxonomic Compositions of Microbial Community (VITCOMIC)). Analysis of the community structure revealed significant differences in community structures in relation to the soil series, which differed particularly in the relative abundance of Cyanobacteria and Firmicutes. However, no significant differences were observed with respect to root microsite location in the same Andisol series. Predominant taxa included members of the Proteobacteria, Actinobacteria, and Acidobacteria. Analysis by VITCOMIC showed that dominant bacterial groups comprised only 5 to 10 % of the total bacterial community and the remaining majority of bacteria included low-abundant taxa (Fusobacteria, Thermotogae, Lentisphaerae, Tenericutes, Deferribacteres Spirochaetes, Planctomycetes, Thermotogae, and Deinococcus-Thermus), most of which have not been previously reported or associated with the plant rhizosphere according to GenBank database. The results indicate that most of bacteria in the Chilean Andisols have not been described to the rhizosphere plants and their functional traits are still largely unknown.     

Determination of the secondary structure of Kluyveromyces lactis beta-galactosidase by circular dichroism and its structure-activity relationship as a function of the pH

The secondary structure of Kluyveromyces lactis beta-galactosidase was determined by circular dichroism. It is mainly a beta-type protein, having 22% beta-turns, 14% parallel beta-sheet, 25% antiparallel beta-sheet, 34% unordered structure, and only 5% alpha-helix. The structure-activity relationship as a function of the pH was also studied. The pH conditions leading to the highest secondary structure content (100% ellipticity) of the enzyme was found at pH 7.0; at pH 6.5-7.0, the percent ellipticity decreased slightly, suggesting little structural change, but the activity decreased significantly, probably because of variations in critical residues. On the other hand, at pH's above 7.0, a more noticeable change in ellipticity was observed due to structural changes; the CD analysis showed a small increase in the helical content toward higher pH, whereas the maximum activity was found at pH 7.5, meaning that the changes produced in the secondary structure at this pH favored the interaction between the enzyme and the substrate.     

Integrating stakeholders’ demands and scientific knowledge on ecosystem services in landscape planning

The conflict between conservation and timber production is shifting in regions such as Biscay (Basque Country, northern Spain) where planted forests are no longer profitable without public subsidies and environmentalist claim that public subsidies should be reoriented to the regeneration of natural forest. This paper develops an approach that integrates scientific knowledge and stakeholders’ demands to provide decision-making guidelines for the development of new landscape planning strategies while considering ecosystem services. First, a participatory process was conducted to develop a community vision for the region’s sustainable future considering the opportunities and constrains provided by the landscape and its ecosystems. In the participatory process forest management was considered an important driver for the region`s landscape development and forest multi-functionality was envisioned as a feasible attractive alternative. The participatory process identified a knowledge gap on the synergies and trade-offs between biodiversity and carbon storage and how these depend on different forest types. Second, to study the existing synergies and trade-offs between biodiversity and carbon storage and disentangle the identified knowledge gap, a GIS-based research was conducted based on spatially explicit indicators. Our spatial analysis results showed that natural forests’ contribution to biodiversity and carbon storage is higher than that of the plantations with exotic species in the region. The results from the spatial analysis converged with those from the participatory process in the suitability of promoting, where possible and appropriate, natural forest ecosystems restoration. This iterative learning and decision making process is already showing its effectiveness for decision making, with concrete examples of how the results obtained with the applied approach are being included in planning and decision-making processes.