21 research outputs found

    GlxA is a new structural member of the radical copper oxidase family and is required for glycan deposition at hyphal tips and morphogenesis of <i>Streptomyces lividans</i>

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    Streptomyces lividans displays a distinct dependence on copper to fully initiate morphological development. Evidence has accumulated to implicate the participation of an extracytoplasmic cuproenzyme in morphogenesis. In the present study, we show that GlxA fulfils all criteria to be that cuproenzyme. GlxA is membrane associated and has an active site consisting of a mononuclear copper and a cross-linked Y-C cofactor. The domain organization of the tertiary structure defines GlxA as a new structural member of the mono-copper oxidase family, with copper co-ordination geometry similar to, but spectroscopically distinct from fungal galactose oxidase (Gox). EPR spectroscopy reveals that the oxidation of cupric GlxA generates a protein radical residing on the Y-C cross-link. A variety of canonical Gox substrates (including D-galactose) were tested but none were readily turned over by GlxA. A glxA null-mutant leads to loss of glycan accumulation at hyphal tips and consequently a drastically changed morphology both on solid substrates and in liquid-grown environments, a scenario similarly observed in the absence of the neighbouring glycan synthase CslA (cellulase synthase-like protein). In addition the glxA mutant has lost the stimulation of development by copper, supporting a model whereby the enzymatic action of GlxA on the glycan is required for development and morphology. From a biotechnology perspective, the open mycelium morphology observed with the glxA mutant in submerged culture has implications for use as an enzyme production host.</jats:p

    Survival and echocardiographic evaluation of dogs with idiopathic dilated cardiomyopathy treated with carvedilol Avaliação ecocardiográfica e de sobrevida de cães com cardiomiopatia dilatada idiopática tratados com carvedilol

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    Sixty dogs with idiopathic dilated cardiomyopathy were randomly treated with traditional therapy - digitalis, diuretics, angiotensin-converting inhibitors - (group A) or treated with these drugs plus carvedilol (group B). Echocardiographic variables were measured before and after 3, 13, 26, and 52 weeks of treatment or until death. Comparisons between groups and time were performed. No significant differences between groups were found in the most of the echocardiographic variables. The left ventricular end-systolic diameter indexed to body surface area (LVESDi) increased significantly in the group A dogs compared to the group B animals. The survival of groups A and B dogs were not different (P-value=0.1137). In conclusion, the stability of the LVESDi observed in the group treated with carvedilol may represent the beneficial effect over the ventricular remodeling.Sessenta cães com cardiomiopatia dilatada idiopática receberam, aleatoriamente, tratamento convencional - digitálicos, diuréticos, inibidores da enzima conversora de angiotensina - (grupo A) ou esses fármacos mais carvedilol (grupo B). As variáveis ecocardiográficas foram avaliadas antes e depois de três, 13, 26 e 52 semanas de tratamento ou até o óbito. Não foram encontradas diferenças significativas entre os grupos de animais quanto à maioria das variáveis ecocardiográficas. O diâmetro sistólico final do ventrículo esquerdo indexado à superfície corpórea (DSVEi) aumentou de forma significativa no grupo A quando comparado ao grupo B. Não se observou diferença na sobrevida dos grupos A e B (P=0,1137). Concluiu-se que a estabilização do DSVEi no grupo tratado com carvedilol pode representar o efeito benéfico deste fármaco sobre o remodelamento ventricular

    A comparison between slaughter traits and meat quality of various sheep breeds: Wool, dual-purpose and mutton

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    The slaughter and meat quality traits of 20-month-old wool (Merino), dual-purpose (Dohne Merino and South African Mutton Merino [SAMM]) and mutton (Dormer) type sheep were compared. Average live weights of SAMM and Dormer sheep were 23% heavier than those of Dohne Merinos which were 28% heavier than Merinos. Fat depths at the thirteenth rib and lumbar regions of Merino and Dohne Merino sheep were lower than those of SAMM and Dormer sheep. The cooking loss, drip loss and shearing value from the M. longissimus dorsi did not differ between breeds. The initial juiciness and sustained juiciness of meat from Merinos were rated significantly lower by sensory analysis. Meat from Dohne Merino was rated significantly more tender for the attribute first bite. It was demonstrated that Dormer and SAMM sheep had heavier but fatter carcasses than Merinos and Dohne Merinos, with differences in meat quality between breeds. © 2012 Elsevier Ltd

    Effect of production system on the growth rate, carcass characteristics and carcass composition of Dorper lambs

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    An investigation on the effect of production system on growth rate, carcass characteristics and carcass composition of Dorper lambs was carried out under South African conditions. The study involved sixty lambs which were divided into two production/feeding groups (feedlot (FL) vs. free-range (FR)) at weaning. Each group consisted of 10 lambs from three gender classes (ewes, rams and castrates). The FL-lambs were fed a commercial pelleted ration while the FR-group grazed natural pastures. The production system x gender interaction indicated that male lambs (castrates and rams) grew twice as fast as ewes under FL-conditions. Gender groups were less pronounced in FR-lambs. FL-lambs produced heavier carcasses, higher dressing percentages and greater carcass fatness levels than FR-lambs. Ram lambs attained heavier slaughter weights and produced heavier carcasses than ewe lambs with castrates being intermediate. Production system did not have an effect on intramuscular lipid concentration, barring a tendency in the Biceps femoris muscle. It was concluded that the FL-diets were generally associated with better lamb growth rates, greater carcass fatness and an improved dressing percentage. Although animal performance was generally improved in the more intensive FL-system, it was also concluded that discerning consumers will likely prefer the more natural (and therefore more ethically acceptable) FR-meat

    Comparison of six crossbred lamb types: Sensory, physical and nutritional meat quality characteristics

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    The effect of crossbreeding on lamb meat quality was examined on the M. longissimus dorsi and M. semimembranosus of South African lamb breed combinations. The lambs were sired by Dormer (D) and Suffolk (S) rams and born to Merino (M), Dohne Merino (DM) and SA Mutton Merino (SAMM) ewes to give six breed combinations. Ratings of sensory attributes on the M. semimembranosus of the different lamb breed combinations were obtained from a trained descriptive panel. The moisture, total lipids, protein, ash, mineral content and fatty acid composition of the M. semimembranosus were also obtained. Physical parameters measured on the M. longissimus dorsi were: pH48, drip loss, cooking loss and Warner-Bratzler shear force (WBS). Breed did not have a significant effect (P &gt; 0.05) on the sensory quality of lamb, except for D × SAMM lambs which only showed a significantly higher (P ≤ 0.05) initial juiciness compared to S×M. However, breed had a significant effect on pH 48, WBS, protein content and the fatty acid and mineral composition. © 2003 Elsevier Ltd. All rights reserved.Articl

    Microbial and volatile profiling of soils suppressive to Fusarium culmorum of wheat

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    In disease-suppressive soils, microbiota protect plants from root infections. Bacterial members of this microbiota have been shown to produce specific molecules that mediate this phenotype. To date, however, studies have focused on individual suppressive soils and the degree of natural variability of soil suppressiveness remains unclear. Here, we screened a large collection of field soils for suppressiveness to Fusarium culmorum using wheat (Triticum aestivum) as a model host plant. A high variation of disease suppressiveness was observed, with 14% showing a clear suppressive phenotype. The microbiological basis of suppressiveness to F. culmorum was confirmed by gamma sterilization and soil transplantation. Amplicon sequencing revealed diverse bacterial taxonomic compositions and no specific taxa were found exclusively enriched in all suppressive soils. Nonetheless, co-occurrence network analysis revealed that two suppressive soils shared an overrepresented bacterial guild dominated by various Acidobacteria. In addition, our study revealed that volatile emission may contribute to suppression, but not for all suppressive soils. Our study raises new questions regarding the possible mechanistic variability of disease-suppressive phenotypes across physico-chemically different soils. Accordingly, we anticipate that larger-scale soil profiling, along with functional studies, will enable a deeper understanding of disease-suppressive microbiomes.</p

    Data from: Microbial and volatile profiling of soils suppressive to Fusarium culmorum of wheat

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    In disease-suppressive soils, microbiota protect plants from root infections. Bacterial members of this microbiota have been shown to produce specific molecules that mediate this phenotype. To date, however, studies have focused on individual suppressive soils and the degree of natural variability of soil suppressiveness remains unclear. Here, we screened a large collection of field soils for suppressiveness to Fusarium culmorum using wheat (Triticum aestivum) as a model host plant. A high variation of disease suppressiveness was observed, with 14% showing a clear suppressive phenotype. The microbiological basis of suppressiveness to F. culmorum was confirmed by gamma sterilization and soil transplantation. Amplicon sequencing revealed diverse bacterial taxonomic compositions and no specific taxa were found exclusively enriched in all suppressive soils. Nonetheless, co-occurrence network analysis revealed that two suppressive soils shared an overrepresented bacterial guild dominated by various Acidobacteria. In addition, our study revealed that volatile emission may contribute to suppression, but not for all suppressive soils. Our study raises new questions regarding the possible mechanistic variability of disease-suppressive phenotypes across physico-chemically different soils. Accordingly, we anticipate that larger-scale soil profiling, along with functional studies, will enable a deeper understanding of disease-suppressive microbiomes.,Ossowicki&amp;Tracanna 16S amplicon data, part 1 Raw FASTQ files of 16S amplicon data. Part 1 of 2-part tarball. Join the two parts using 'cat' before extracting. Ossowicki_Tracanna_16S_amplicon_data.tar.gz.part_aa Ossowicki&amp;Tracanna 16S amplicon data, part 2 Raw FASTQ files of 16S amplicon data. Part 1 of 2-part tarball. Join the two parts using 'cat' before extracting. Ossowicki_Tracanna_16S_amplicon_data.tar.gz.part_ab

    User requirements for assistance of the supporting hand in bimanual daily activities via a robotic glove for severely affected stroke patients

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    For independent functioning in activities of daily life (ADL), proper hand function is paramount. Many stroke patients have a reduced ability to grasp and handle objects, while they don't fully recover functional use of the arm and hand, even after extensive (robotic) training. These patients may benefit from assistive support of the arm and hand in daily life. To address the needs of stroke patients during the design of an assistive device, a user-centered approach has been applied to identify user requirements for development of a dynamic hand orthosis to support hand opening during functional bimanual activities. A survey of literature showed that preferred ADL tasks are personal hygiene, dressing-grooming, eating and preparing food. Since the more affected hand will mainly be used as a supporting hand to stabilize objects during prehensile tasks, the most important grasp to support was identified as the cylinder grasp. User requirements were extracted from interviews with primary and secondary end-users and experts in the field, highlighting that ease of use is an essential aspect for user acceptance and uptake of the devic
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