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Patterning and differentiation of eye cell types of the Drosophila melanogaster occurs sequentially within an epithelial monolayer--the eye-antennal disc. One of the final events in this process is the elimination of surplus cells by programmed cell death. The best characterized among the loci involved in this final patterning event is roughest-irregular chiasm C (rst-irreC), which encodes a transmembrane glycoprotein belonging to the immunoglobulin superfamily. Mutations in this gene cause defects in the wave of programmed cell death during the pupal stage leading to the presence of extra secondary and tertiary pigmentary cells and 'rough' eyes. Here we present evidence, based on the phenotype and molecular characterization of rstD, a novel dominant allele of rst-irreC, and its revertants, that the precise temporal and spatial expression of this gene is also a necessary requeriment for secondary and tertiary pigment cell fate specification.

Visceral leishmaniasis is a zoonosis in which the dog appears as the main source of infection in urban areas. Its diagnosis is complex and the cytopathological exam is a fast and cheap alternative to parasite direct visualization and its sensitivity can be increased by immunocytochemistry, though with a higher cost. The accuracy of such methods is dependent on the microscopist's experience and therefore, this study evaluated the reliability of such techniques between two observers, from bone marrow aspirates of 50 dogs from an endemic area for the disease. The parasitological culture in Novy-MacNeal-Nicolle medium was used as the reference standard. Among the main findings, the sensitivities obtained by observers I and II were respectively 62.5% and 37.5%, while specificities were 81.1% and 100%. On immunocytochemistry evaluation, the sensitivity was 0% for both evaluators and the specificity 97.3% and 100%. The agreement between evaluators was weak (κ = 0.167) for the cytopathological test and it could not be evaluated for immunocytochemistry, for which there was no detection by the evaluator II. The agreements among the diagnostic methods and the standard reference for the observer I were reasonable (κ = 0.364) for cytopathological examination and bad (κ = -0.041) for immunocytochemistry. For observer II, such agreement could be assessed only for the cytopathological test, being moderate (κ = 0.497). The results point to the possible expertise difference between evaluators, with the evaluator II demonstrating greater experience when interpreting the citopathological test. Although there was the expected sensitivity increase with immunocytochemistry, the technique used in this study was not effective for the diagnosis of infection, regardless of the evaluator. [ABSTRACT FROM AUTHOR]

Heel erosion is the most prevalent hoof lesion in housed dairy herds, particularly in freestall facilities. It is associated with hoof contact with manure slurry and abrasive floors. The objective was to assess changes in the risk of heel erosion from the dry period to mid lactation in primiparous and multiparous dairy cows. Nineteen pregnant primiparous cows, 22 late-lactation multiparous cows (parity=3.2±1.4; days in milk=221±38), and 16 nonlactating, pregnant multiparous cows (parity=3.7±1.4) housed in a freestall barn with concrete flooring were followed until mid lactation. The hind hooves of all the cows were examined approximately every 7 wk and heel erosion was scored. Multiparous cows more likely had heel erosion than primiparous cows (odds ratio=11.0; 95% confidence interval=3.7, 32.7). Time relative to calving showed a significant quadratic effect, revealing that the risk of heel erosion increased more rapidly as lactation progressed. Survival analysis showed that multiparous cows had a higher relative risk of developing heel erosion than primiparous cows (hazard ratio=3.4). No cows improved between early and mid lactation, but 18 cows worsened. In conclusion, stage of lactation and parity were major risk factors for severe heel erosion in dairy cattle housed in freestalls. [ABSTRACT FROM AUTHOR]

Cowpea is a leguminous plant belonging to the fabaceae family cultivated in the North and Northeast regions of Brazil, with productive potential. Among the abiotic factors, water deficiency is one of the main environmental limitations that influence agricultural production in the world. The objective of this work was to study the relative water content and osmoregulators of cowpea plants subjected to water stress. The experiment was carried out in a greenhouse at the Universidade Federal Rural da Amazônia (UFRA, Belém, PA), cowpea plants BR-17 Gurguéia Vigna unguiculata (L.) Walp were used. The experimental design was completely randomized (DIC) in a 2 × 2 factorial scheme, two water conditions (control and water deficit) and two times of stress (four and six days of water suspension), with 7 replications, totaling 28 experimental units. The water deficit affected plants, causing a reduction in relative water content (69.98%), starch (12.84% in leaves and 23.48% in roots) and carbohydrates (84.34%), and an increase in glycine-betaine, sucrose (114.11% in leaves and 18.71% in roots) and proline (358.86%) at time 2. The relative water content was negatively affected by water conditions, with a decrease in relation to the interaction of the aerial part and the root system. Therefore, greater metabolic responses were noted in plants that were subjected to stress treatment at time 2 (6 days).

The galactose oxidase-producing fungus Dactylium dendroides was re-identified as a Fusarium species. Fungi of this genus are well known for the production of mycotoxins. Verification of growth of this fungus on rice, corn and liquid medium described for the production of galactose oxidase is provided to determine whether the fungus could produce Fusarium toxins, namely, moniliformin, fusaric acid, fumonisin, zearalenone and the trichothecenes, deoxynivalenol, 3-acetyldeoxynivalenol, fusarenone, nivalenol, diacetoxyscirpenol, neosolaniol, and toxin T-2. Under the culture conditions used, deoxynivalenol, 3-acetyldeoxynivalenol and zearalenone were detected in the fungal culture medium. The finding is consistent with the hypothesis that the fungus is in fact a Fusarium species.