Trichoderma species are found in soil and in association with plants. They can act directly or indirectly in the biological control of plant diseases and in the promotion of plant growth, being among ...the most used fungi in the formulation of bioproducts applied to agricultural systems. The main objective of this study was to characterize at a first-tier level a collection of 67 Trichoderma isolates from various tropical sources, based solely on sequencing of the internal transcribed spacer (ITS) region of the rRNA genes. Our goal was to provide a preliminary idea of the baseline diversity in this collection, to combine this information later with an array of other isolate-specific physiological data. This study provides a required knowledge at molecular level for assessment of this germplasm potential as a source of biotechnological products for beneficial effects in plants.
Sequencing of the ITS region showed that the 67 Trichoderma isolates belonged in 11 species: T. asperellum, T. atroviride, T. brevicompactum, T. harzianum, T. koningiopsis, T. longibrachiatum, T. pleuroticola, T. reesei, T. spirale, T. stromaticum and T. virens. A total of 40.3% of the isolates were very closely related to each other and similar to T. harzianum. The baseline genetic diversity found indicates that the collection has different genotypes, which can be exploited further as a source of bioproducts, aiming at providing beneficial effects to plants of interest to cope with biotic and abiotic stresses.
Selenium (Se) is considered a beneficial element to higher plants based on its regulation of antioxidative system under abiotic or biotic stresses. However, the limit of beneficial and toxic ...physiological effects of Se is very narrow. In the present study, the antioxidant performance, nutritional composition, long-distance transport of Se, photosynthetic pigments, and growth of Coffea arabica genotypes in response to Se concentration in solution were evaluated. Five Coffea arabica genotypes (Obatã, IPR99, IAC125, IPR100 and Catucaí) were used, which were grown in the absence and presence of Se (0 and 1.0 mmol L−1) in nutrient solution. The application of 1 mmol L−1 Se promoted root browning in all genotypes. There were no visual symptoms of leaf toxicity, but there was a reduction in the concentration of phosphorus and sulfur in the shoots of plants exposed to high Se concentration. Except for genotype Obatã, the coffee seedlings presented strategies for regulating Se uptake by reducing long-distance transport of Se from roots to shoots. The concentrations of total chlorophyll, total pheophytin, and carotenoids were negatively affected in genotypes Obatã, IPR99, and IAC125 upon exposure to Se at 1 mmol L−1. H2O2 production was reduced in genotypes IPR99, IPR100, and IAC125 upon exposure to Se, resulting in lower activity of superoxide dismutase (SOD), and catalase (CAT). These results suggest that antioxidant metabolism was effective in regulating oxidative stress in plants treated with Se. The increase in sucrose, and decrease in SOD, CAT and ascorbate peroxidase (APX) activities, as well as Se compartmentalization in the roots, were the main biochemical and physiological modulatory effects of coffee seedlings under stress conditions due to excess of Se.
•Excess Se does not cause visual toxicity in leaves of coffee seedlings.•Se increased the antioxidant metabolism and sugars compounds.•There was a genotypic variation of coffee plants for Se toxicity.•Sugars associated with antioxidant enzymes are effective biomarkers for Se toxicity in coffee plants.
To verify the auditory-perceptual and acoustic effects of the semioccluded vocal tract exercise with Finnish tube on the vocal quality of a deaf musician.
A seven-day protocol with Finnish tube was ...performed with guidance for its home replication twice a day. A 46-years-old man with profound bilateral sensorineural hearing loss, musician and composer participated. Before and after the application of the protocol had undergone tonal audiometry, nasofibrolaryngoscopy, acoustic analysis with Praat and auditory-perceptual evaluation of the voice with Voice Profile Analysis Scheme for Brazilian Portuguese.
The postintervention auditory-perceptual analysis identified reduction of the deviation in lip spreading, extensive labial range, raised tongue body, pharyngeal expansion, nasal resonance, larynx height, larynx and vocal tract tension and irregularity, pitch, speech rate, and a better respiratory support. The maximum phonation time reduced, probably because of elimination of the abrupt vocal attack and tension, articulatory deviations, improvement in voicing and the absence of the use of expiratory reserve air. The fundamental frequency became lower, and the first, second, third, and fourth formants became higher. The jitter increased, and the shimmer reduced.
The use of the Finnish tube might have facilitated the voicing sensations in the deaf musician, by enhancing the tactile-kinesthetic perception of the vocal tract and brought a greater source-filter interaction.
The relationships between monocytes and lymphocytes through MHC class II molecules and costimulatory, are of utmost importance for the production of an efficient immune response. In this work, we ...assessed the expression of surface molecules CD80 and CD86 on CD14+HLA-DR+ monocytes from patients with Chagas disease.
The study population consisted of 31 patients with chronic clinical forms of Chagas disease. Patient blood samples were cultured in the presence of recombinant cytoplasmic repetitive antigen (CRA) and flagellar repetitive antigen (FRA).
We found considerable differences in the expression profile of surface molecules involved in antigen presentation.
CRA and FRA may contribute to host immune response evasion by Trypanozoma cruzi.
PDF
