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OBJECTIVE: The objective of the study is to evaluate the characteristics and outcomes of patients with abdominal aortic aneurysm (AAA) and its correlation with mortality in the first 30 days after the procedure was performed. METHODS: Demographic information, clinical and radiological characteristics, as well as outcomes 30 days after the procedure was performed were assessed and compared. Continuous variables were analyzed with Student's t-test and categorical with Chi-square and Fisher's exact test. RESULTS: Duration of the procedure (p = 0.001), blood loss (p < 0.001), age > 75 years (p = 0.027), aneurysm size > 65 mm (p = 0.01), open surgery (p = 0.001), presence of pain (p = 0.005), chronic kidney disease (p = 0.03), and rupture of the aneurysm (p < 0.001) were the factors significantly associated with mortality. CONCLUSION: It is essential that patient characteristics and comorbidities are assessed, as well as factors that may affect the outcomes to predict the prognosis in patients with AAA. At present, no mortality predictive model is universally applicable and highly variable performance across different populations might need a model that adapts to the population of interest.

OBJETIVO: Evaluar las características y resultados de los pacientes con aneurisma de aorta abdominal y su correlación con la mortalidad en los primeros 30 días después de realizado el procedimiento. MÉTODOS: Se evaluó y comparó la información demográfica, las características clínicas y radiológicas, así como los resultados a los 30 días de realizado el procedimiento. Las variables continuas se analizan con la prueba de t de Student y las categóricas con Chi-cuadrado y la prueba exacta de Fisher. RESULTADOS: La duración del procedimiento (p = 0.001), pérdida de sangre (p < 0.001), edad > 75 años (p = 0.027), tamaño del aneurisma > 65 mm (p = 0.01), cirugía abierta (p = 0.001), presencia de dolor (p = 0.005), enfermedad renal crónica (p = 0.03) y rotura del aneurisma (p < 0.001) fueron los factores asociados significativamente a la mortalidad. CONCLUSIÓN: Es fundamental evaluar las características de los pacientes y las comorbilidades, así como los factores que pueden afectar los resultados para predecir el pronóstico en pacientes con aneurisma de aorta abdominal. En la actualidad, ningún modelo predictivo de mortalidad es universalmente aplicable y la alta variabilidad de resultados entre diferentes poblaciones podría necesitar un modelo que se adapte a la población de interés.

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To contribute to studies in Psychology through a systematic and methodological analysis of the comparison between a tree and the cognitive model of the cognitive behavioral theory, establishing similarities and differences between the comparative domains. Method It is a qualitative, exploratory, documentary research, based on the Conceptual Metaphor, the Cognitive-Behavioral Theory, and on the Methodology of Teaching with Analogies. It starts from the hypothesis of the existence of a conceptual metaphor in which "the cognitive model is structured like a tree", transposing characteristics between both. It verifies, classifies, analyzes the comparison by means of analogical reasoning and the filling of comparative charts between vehicle and target. Results The results point to the complexity and potential of comparison if treated systematically and methodologically. Conclusion The research results corroborate the hypothesis that originated it.

Este artigo buscou analisar as percepções de pais e professores a respeito da trajetória escolar de crianças adotadas. Para isto, entrevistamos professores do Ensino Fundamental (3º ao 7º ano) e pais adotivos, investigando como compreendem a existência de possíveis sucessos e dificuldades escolares nas crianças adotadas, e se há relação entre adoção e atuação escolar. Método A pesquisa é qualitativa, exploratória, documental, fundamentada na Metáfora Conceptual, na Teoria Cognitivo-Comportamental e na Metodologia de Ensino com Analogias e parte da hipótese da existência de uma metáfora conceptual em que "o modelo cognitivo se estrutura como uma árvore", transpondo características entre ambos. Verifica-se, classifica-se e analisa-se a comparação por meio de raciocínio analógico e do preenchimento de quadros comparativos entre veículo e alvo. Resultados Os resultados apontam a complexidade e o potencial da comparação, caso seja tratada sistemática e metodologicamente. Conclusão A hipótese de pesquisa é corroborada.

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Coffea canephora (2n = 2x = 22 chromosomes) is a species with extensive genetic diversity and desirable agronomic traits for coffee breeding programs. However, obtaining a new coffee cultivar through conventional breeding techniques may require more than 30 years of crossing cycles and selection, which hampers the effort of keeping up with market demands and rapidly proposing more resilient to climate change varieties. Although, the application of modern biotechnology tools such as precision genetic engineering technologies may enable a faster cultivar development process. Therefore, we aimed to validate the CRISPR/Cas9 system to generate mutations on a selected genotype of C. canephora, the clone 14. Embryogenic calli and a multiplex binary vector containing two sgRNAs targeting different exons of the CcPDS gene were used. The sgRNAs were under the C. canephora U6 promoter regulation. The target gene encodes phytoene desaturase, an enzyme essential for photosynthesis involved in ß-carotene biosynthesis. Somatic seedlings and embryos with albino, variegated and green phenotypes regenerated after Agrobacterium tumefaciens-mediated genetic transformation were analyzed by verifying the insertion of the Cas9 gene and later by sequencing the sgRNAs target regions in the genome of Robusta modified seedlings. Among them, 77% had the expected mutations, and of which, 50% of them had at least one target with a homozygous mutation. The genotype, temperature of co-cultivation with the bacteria, and light intensity used for subsequent embryo regeneration appeared to strongly influence the successful regeneration of plants with a mutated CcPDS gene in the Coffea genus.

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Amphibians secrete a complex array of molecules that shape their interactions with coinhabiting microorganisms and macroscopic predators. Glycans are a rapidly evolving and complex class of biomolecules implicated in intrinsic and extrinsic recognition events. Despite the numerous studies aiming at the biochemical characterization of anuran skin secretions, little is known about protein-linked oligosaccharides, their synthesis pathways, and their homing secreted glycoproteins. In the present report, LC-MS/MS was used to investigate the diversity of N- and O-linked oligosaccharides in the skin secretion of two South American frogs, Pithecopus azureus and Boana raniceps. Additionally, the enzymes responsible for glycan synthesis pathways were evaluated based on their skin tissue transcriptome. Our analyses allowed the annotation of various N- and O-glycan structures commonly found in vertebrate proteins. Paucimannosidic glycans were abundant in the skin secretion of both amphibians; however, hybrid and complex N-glycan structures were detected only in B. raniceps. A good correlation between the structures discovered in glycomic analyses and transcripts encoding enzymes necessary for their synthesis was obtained. Some transcripts such as those of MAN1A2, FUT8, and ST6GALNAC were found solely in B. raniceps. Finally, secreted N- and O- linked glycoproteins were predicted from the transcriptomic data, indicating that proteases and protease inhibitors are putative sources of the glycans described herein. Overall, our results show the presence of oligosaccharides in amphibians skin secretions and suggest that their diversity is species-specific, paving the way for novel perspectives involving amphibian evolution and ecology.

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BACKGROUND: Digital technologies (digiTech) enhance benefits in healthcare and are present in elderly people lives. Healthcare professionals (HCP) who deal with dementia and related disorders face enormous challenges in delivering healthcare using digital devices, and Covid-19 pandemic showed these pitfalls should be addressed. Technology solutions in elder people are being developed, not every HCP is heard, and we lack information about what these professionals think about this. METHODS: Using structured questionnaires and asynchronous electrotonic data capture, we asked experienced (84.3% postgraduate degrees) HCP with different backgrounds (8 practice areas) about what they think of technology use among their patients and carers. The average person in our sample (N = 51) was a highly skilled (22.2 study-years) female (70.6%) medical doctor (62.8%) aged 39.1 years old (27 to 77 years), highly exposed to digiTech (68.6% mobile devices usage ≥4 hours/day). Neurologists (37.3%), neuropsychologists (15.7%), psychiatrists (13.7%), geriatricians (11.8%) were the most represented groups. This observational cross-sectional study is part of a Brazilian pilot study to explore technology usage in higher risk dementia adults (DigiTAU Project). RESULTS: Although HCP consider asking patients and carers about technology use to be theoretically important (90.2%) and useful in practice (94.2%), they often do not do it (45.1%). There is incongruity when they feel safe to offer interventions by digital means (58.8%) but commonly agree, on average, that HCP are not prepared to use digiTech (51.0%). Despite having positive views towards benefits in adopting digiTech for patients (98.1%), they think they bring more benefits to families and caregivers than to patients themselves (56.9%). HCP consider digiTech will change their practice in the short term within 1 year (58.8%) and within 5 years (88.3%). None of the 8 options suggested as the most "promising" technology in 10 years reaches more than 25% of the choices. CONCLUSIONS: HCP have conflicting views about the usage of technologies by their patients and caregivers but expect some positive changes in their work practice. It suggests new digiTech must be submitted to scrutiny so that its applicability overcomes the challenges. Further studies and analysis are needed to understand better this data.

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The aim of this study was to identify the correlation between photochemical efficiency and candidate genes expression to elucidate the drought tolerance mechanisms in coffee progenies (Icatu Vermelho IAC 3851-2 × Catimor UFV 1602-215) previously identified as tolerant in field conditions. Four progenies (2, 5, 12 and 15) were evaluated under water-deficit conditions (water deficit imposed 8 months after transplanting seedlings to the pots) and under irrigated system. Evaluations of physiological parameters and expression of candidate genes for drought tolerance were performed. Progeny 5 showed capacity to maintain water potential, which contributed to lower qP variation between irrigated and deficit conditions. However, the increases of qN and NPQ in response to stress indicate that this progeny is photochemically responsive to small variations of Ψam protecting the photosystem and maintaining qP. Data obtained for progeny 12 indicated a lower water status maintenance capacity, but with increased qN and NPQ providing maintenance of the ɸPSII and ETR parameters. A PCA analysis revealed that the genes coding regulatory proteins, ABA-synthesis, cellular protectors, isoforms of ascorbate peroxidase clearly displayed a major response to drought stress and discriminated the progenies 5 and 12 which showed a better photochemical response. The genes CaMYB1, CaERF017, CaEDR2, CaNCED, CaAPX1, CaAPX5, CaGolS3, CaDHN1 and CaPYL8a were up-regulated in the arabica coffee progenies with greater photochemical efficiency under deficit and therefore contributing to efficiency of the photosynthesis in drought tolerant progenies.

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The phytocannabinoids of Cannabis sativa L. have, since ancient times, been proposed as a pharmacological alternative for treating various central nervous system (CNS) disorders. Interestingly, cannabinoid receptors (CBRs) are highly expressed in the basal ganglia (BG) circuit of both animals and humans. The BG are subcortical structures that regulate the initiation, execution, and orientation of movement. CBRs regulate dopaminergic transmission in the nigro-striatal pathway and, thus, the BG circuit also. The functioning of the BG is affected in pathologies related to movement disorders, especially those occurring in Parkinson's disease (PD), which produces motor and non-motor symptoms that involving GABAergic, glutamatergic, and dopaminergic neural networks. To date, the most effective medication for PD is levodopa (l-DOPA); however, long-term levodopa treatment causes a type of long-term dyskinesias, l-DOPA-induced dyskinesias (LIDs). With neuromodulation offering a novel treatment strategy for PD patients, research has focused on the endocannabinoid system (ECS), as it participates in the physiological neuromodulation of the BG in order to control movement. CBRs have been shown to inhibit neurotransmitter release, while endocannabinoids (eCBs) play a key role in the synaptic regulation of the BG. In the past decade, cannabidiol (CBD), a non-psychotropic phytocannabinoid, has been shown to have compensatory effects both on the ECS and as a neuromodulator and neuroprotector in models such as 6-hydroxydopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and reserpine, as well as other PD models. Although the CBD-induced neuroprotection observed in animal models of PD has been attributed to the activation of the CB1 receptor, recent research conducted at a molecular level has proposed that CBD is capable of activating other receptors, such as CB2 and the TRPV-1 receptor, both of which are expressed in the dopaminergic neurons of the nigro-striatal pathway. These findings open new lines of scientific inquiry into the effects of CBD at the level of neural communication. Cannabidiol activates the PPARγ, GPR55, GPR3, GPR6, GPR12, and GPR18 receptors, causing a variety of biochemical, molecular, and behavioral effects due to the broad range of receptors it activates in the CNS. Given the low number of pharmacological treatment alternatives for PD currently available, the search for molecules with the therapeutic potential to improve neuronal communication is crucial. Therefore, the investigation of CBD and the mechanisms involved in its function is required in order to ascertain whether receptor activation could be a treatment alternative for both PD and LID.

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ABSTRACT Background: There has been a revolution in the treatment of Chronic Myeloid Leukemia since imatinib's introduction. However, patient adherence has a great impact on the response obtained with medical treatment. This study's objective was to analyze the drug adherence and the factors that influenced it in patients with Chronic Myeloid Leukemia in a referral hospital in the Brazilian Amazon. Method: This was a retrospective study including 120 patients with Chronic Myeloid Leukemia from January 2002 to December 2014. The adherence was estimated by the Proportion of Days Covered and the persistence by Kaplan-Meier analysis. The data was analyzed in Epi Info 7® software and the relationship between the variables was analyzed by Fisher's exact test. A p-value lower than 0.05 was considered significant. Results: Twenty-seven patients (22.5%) were considered non-adherent. There has been irregular medication use and disinterest in the treatment in 20.83% (n = 25), of which 13 were considered non-adherent (p < 0.001). A total of 26.67% (n = 32) abandoned the treatment for a period. Of those, 56.25% (n = 18) were non-adherent (p < 0.001). Distance to the hospital, lack of medication and side-effects were all non-significant to low adherence. At the end of a 360-day follow-up, 44.16% (n = 53) of patients presented a break in persistence, whose average was 255 days. Conclusion: The adherence found in this study was similar to that found in others of its kind. The only factors that negatively influenced the adherence were disinterest and abandonment of treatment, which can reflect the need to individually educate Chronic Myeloid Leukemia patients.

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BACKGROUND AND OBJECTIVE: Leukaemia is a disease found worldwide; it is a type of cancer that originates in the bone marrow and is characterised by an abnormal proliferation of white blood cells (leukocytes). In order to correctly identify this abnormality, haematologists examine blood smears from patients. A diagnosis obtained by this method may be influenced by factors such as the experience and level of fatigue of the haematologist, resulting in non-standard reports and even errors. In the literature, several methods have been proposed that involve algorithms to diagnose this disease. However, no reviews or surveys have been conducted. This paper therefore presents an empirical investigation of computational methods focusing on the segmentation of leukocytes. METHODS: In our study, 15 segmentation methods were evaluated using five public image databases: ALL-IDB2, BloodSeg, Leukocytes, JTSC Database and CellaVision. Following the standard methodology for literature evaluation, we conducted a pixel-level segmentation evaluation by comparing the segmented image with its corresponding ground truth. In order to identify the strengths and weaknesses of these methods, we performed an evaluation using six evaluation metrics: accuracy, specificity, precision, recall, kappa, Dice, and true positive rate. RESULTS: The segmentation algorithms performed significantly differently for different image databases, and for each database, a different algorithm achieved the best results. Moreover, the two best methods achieved average accuracy values higher than 97%, with an excellent kappa index. Also, the average Dice index indicated that the similarity between the segmented leukocyte and its ground truth was higher than 0.85 for these two methods This result confirms the high level of similarity between these images but does not guarantee that a method has segmented all leukocyte nuclei. We also found that the method that performed best segmented only 58.44% of all leukocytes. CONCLUSIONS: Of the techniques used to segment leukocytes, we note that clustering algorithms, the Otsu threshold, simple arithmetic operations and region growing are the approaches most widely used for this purpose. However, these computational methods have not yet overcome all the challenges posed by this problem.

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BACKGROUND: There has been a revolution in the treatment of Chronic Myeloid Leukemia since imatinib's introduction. However, patient adherence has a great impact on the response obtained with medical treatment. This study's objective was to analyze the drug adherence and the factors that influenced it in patients with Chronic Myeloid Leukemia in a referral hospital in the Brazilian Amazon. METHOD: This was a retrospective study including 120 patients with Chronic Myeloid Leukemia from January 2002 to December 2014. The adherence was estimated by the Proportion of Days Covered and the persistence by Kaplan-Meier analysis. The data was analyzed in Epi Info 7® software and the relationship between the variables was analyzed by Fisher's exact test. A p-value lower than 0.05 was considered significant. RESULTS: Twenty-seven patients (22.5%) were considered non-adherent. There has been irregular medication use and disinterest in the treatment in 20.83% (n=25), of which 13 were considered non-adherent (p<0.001). A total of 26.67% (n=32) abandoned the treatment for a period. Of those, 56.25% (n=18) were non-adherent (p<0.001). Distance to the hospital, lack of medication and side-effects were all non-significant to low adherence. At the end of a 360-day follow-up, 44.16% (n=53) of patients presented a break in persistence, whose average was 255 days. CONCLUSION: The adherence found in this study was similar to that found in others of its kind. The only factors that negatively influenced the adherence were disinterest and abandonment of treatment, which can reflect the need to individually educate Chronic Myeloid Leukemia patients.

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Coffee yields are adversely affected by plant-parasitic nematodes and the pathogens are largely underreported because a simple and reliable identification method is not available. We describe a polymerase chain reaction-based approach to rapidly detect and quantify the major Pratylenchus and Meloidogyne nematode species that are capable of parasitizing coffee. The procedure was applied to soil samples obtained from a number of coffee farms in Brazil, Vietnam, and Indonesia to assess the prevalence of these species associated both with coffee (Coffea arabica and C. canephora) and its intercropped species Musa acuminata (banana) and Piper nigrum (black pepper). Pratylenchus coffeae and P. brachyurus were associated with coffee in all three countries but there were distinct profiles of Meloidogyne spp. Meloidogyne incognita, M. exigua, and M. paranaensis were identified in samples from Brazil and M. incognita and M. hapla were detected around the roots of coffee in Vietnam. No Meloidogyne spp. were detected in samples from Indonesia. There was a high abundance of Meloidogyne spp. in soil samples in which Pratylenchus spp. were low or not detected, suggesting that the success of one genus may deter another. Meloidogyne spp. in Vietnam and Pratylenchus spp. in Indonesia were more numerous around intercropped plants than in association with coffee. The data suggest a widespread but differential nematode problem associated with coffee production across the regions studied. The issue is compounded by the current choice of intercrops that support large nematode populations. Wider application of the approach would elucidate the true global scale of the nematode problem and the cost to coffee production. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

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Analyzes of samples of stem and fiber Boehmeria nivea var. Murakami were performed to increase information on the plant and disseminate its multiple possibilities of use. The histochemical analyzes with dyes and reagents showed the presence of lignified, suberous and cutinized cell walls with Safranin in the xylem region. The presence of pectin-cellulose with Astra Blue was confirmed in the regions of fiber bundles (cortex). In all regions of the stem were identified substances such as fat and mucilage with Methylene Blue evidencing high concentrations in the regions of fiber bundles and bark (violet blue). By means of Lugol (dark brown) starches were identified in several parts of the stem with concentrations in the xylem and epidermal regions. Through analyzes by EDS it was possible to identify F, Mg, Al, Si, K and Ca with predominance of K. In the chemical analyzes of the fibers were found 71.75 of cellulose, 12.11 of hemicelluloses, 1.06 of lignin and 1.70% of ashes. The percentages of extractives soluble in hot and cold water were 5.28 and 3.12% respectively, for Ethanol-Toluene was 8.55 and NaOH (1%) 27.27%. Histochemical analyzes revealed important characteristics of the fiber and stem contributing with better knowledge of the species.

Análises de amostras de caule e de fibras Boehmeria nivea var. ‘Murakami’ foram realizadas para aumentar o conhecimento da planta e difundir suas múltiplas possibilidades de uso. As análises histoquímicas com corantes e reagentes mostraram paredes celulares lignificadas, suberosas e cutinizadas com Safranina na região do xilema. Confirmou-se a presença de pectocelulose com Azul de Astra nas regiões de feixes de fibras (córtex). Em todas as regiões do caule, foram identificadas substâncias como gordura e mucilagem com Azul de Metileno, evidenciando elevadas concentrações nas regiões dos feixes de fibras e da casca (azul violeta). Por meio de Lugol (marrom escuro), foram identificados amidos em várias partes do caule com concentrações nas regiões do xilema e da epiderme. Por meio de análises de EDS, foram identificados F, Mg, Al, Si, K e Ca, com predominância do K. Nas análises químicas das fibras, foram encontrados 71,09 de celulose, 12,11 de hemiceluloses, 1,06 de lignina e 1,70% de cinzas. As porcentagens de extrativos solúveis em água quente e fria foram de 5,28 e 3,12%, respectivamente. Para o Etanol-Tolueno, foi 8,55 e para o NaOH (1%), 27,27%. As análises histoquímicas revelaram importantes características das fibras e do caule, contribuindo com melhores conhecimentos da espécie

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Analyzes of samples of stem and fiber Boehmeria nivea var. Murakami were performed to increase information on the plant and disseminate its multiple possibilities of use. The histochemical analyzes with dyes and reagents showed the presence of lignified, suberous and cutinized cell walls with Safranin in the xylem region. The presence of pectin-cellulose with Astra Blue was confirmed in the regions of fiber bundles (cortex). In all regions of the stem were identified substances such as fat and mucilage with Methylene Blue evidencing high concentrations in the regions of fiber bundles and bark (violet blue). By means of Lugol (dark brown) starches were identified in several parts of the stem with concentrations in the xylem and epidermal regions. Through analyzes by EDS it was possible to identify F, Mg, Al, Si, K and Ca with predominance of K. In the chemical analyzes of the fibers were found 71.75 of cellulose, 12.11 of hemicelluloses, 1.06 of lignin and 1.70% of ashes. The percentages of extractives soluble in hot and cold water were 5.28 and 3.12% respectively, for Ethanol-Toluene was 8.55 and NaOH (1%) 27.27%. Histochemical analyzes revealed important characteristics of the fiber and stem contributing with better knowledge of the species.(AU)

Análises de amostras de caule e de fibras Boehmeria nivea var. ‘Murakami foram realizadas para aumentar o conhecimento da planta e difundir suas múltiplas possibilidades de uso. As análises histoquímicas com corantes e reagentes mostraram paredes celulares lignificadas, suberosas e cutinizadas com Safranina na região do xilema. Confirmou-se a presença de pectocelulose com Azul de Astra nas regiões de feixes de fibras (córtex). Em todas as regiões do caule, foram identificadas substâncias como gordura e mucilagem com Azul de Metileno, evidenciando elevadas concentrações nas regiões dos feixes de fibras e da casca (azul violeta). Por meio de Lugol (marrom escuro), foram identificados amidos em várias partes do caule com concentrações nas regiões do xilema e da epiderme. Por meio de análises de EDS, foram identificados F, Mg, Al, Si, K e Ca, com predominância do K. Nas análises químicas das fibras, foram encontrados 71,09 de celulose, 12,11 de hemiceluloses, 1,06 de lignina e 1,70% de cinzas. As porcentagens de extrativos solúveis em água quente e fria foram de 5,28 e 3,12%, respectivamente. Para o Etanol-Tolueno, foi 8,55 e para o NaOH (1%), 27,27%. As análises histoquímicas revelaram importantes características das fibras e do caule, contribuindo com melhores conhecimentos da espécie(AU)

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Despite the importance of the DREB1D gene (also known as CBF4) in plant responses to water deficit and cold stress, studies analysing its regulation by transgenic approaches are lacking. In the current work, a functional study of three CcDREB1D promoter haplotypes (named HP15, HP16 and HP17) isolated from drought-tolerant and drought-sensitive clones of Coffea canephora was carried out in plants of C. arabica stably transformed by Agrobacterium tumefaciens by analysing their ability to regulate the expression of the uidA reporter gene in response to water deficit mimicked by polyethylene glycol (-2.0 MPa) and low relative humidity treatments. A deletion analysis of their corresponding 5'-upstream regions revealed increased specificity of ß-glucuronidase activity in the polyethylene glycol and low relative humidity treatments, with high expression in leaf mesophyll and guard cells in full-length constructs. RT-qPCR assays also revealed that the HP16 haplotype (specific to clone tolerant to water deficit) had stronger and earlier activity compared with the HP15 and HP17 haplotypes. As most of the cis-regulatory elements involved in ABA-dependent and -independent networks, tissue specificity and light regulation are common to these haplotypes, we propose that their organization, as well as the nucleic acid polymorphisms present outside these boxes, may play a role in modulating activities of DREB1D promoters in guard cells.

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Acidic soils are distributed worldwide, predominantly in tropical and subtropical areas, reaching around 50% of the arable soil. This type of soil strongly reduces crop production, mainly because of the presence of aluminum, which has its solubility increased at low pH levels. A well-known physiological mechanism used by plants to cope with Al stress involves activation of membrane transporters responsible for organic acid anions secretion from the root apex to the rhizosphere, which chelate Al, preventing its absorption by roots. In sorghum, a membrane transporter gene belonging to multidrug and toxic compound extrusion (MATE) family was identified and characterized as an aluminum-activated citrate transporter gene responsible for Al tolerance in this crop. Setaria viridis is an emerging model for C4 species and it is an important model to validate some genes for further C4 crops transformation, such as sugarcane, maize, and wheat. In the present work, Setaria viridis was used as a model plant to overexpress a newly identified MATE gene from Brachypodium distachyon (BdMATE), closely related to SbMATE, for aluminum tolerance assays. Transgenic S. viridis plants overexpressing a BdMATE presented an improved Al tolerance phenotype, characterized by sustained root growth and exclusion of aluminum from the root apex in transgenic plants, as confirmed by hematoxylin assay. In addition, transgenic plants showed higher root citrate exudation into the rhizosphere, suggesting that Al tolerance improvement in these plants could be related to the chelation of the metal by the organic acid anion. These results suggest that BdMATE gene can be used to transform C4 crops of economic importance with improved aluminum tolerance.

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BACKGROUND: Drought is a widespread limiting factor in coffee plants. It affects plant development, fruit production, bean development and consequently beverage quality. Genetic diversity for drought tolerance exists within the coffee genus. However, the molecular mechanisms underlying the adaptation of coffee plants to drought are largely unknown. In this study, we compared the molecular responses to drought in two commercial cultivars (IAPAR59, drought-tolerant and Rubi, drought-susceptible) of Coffea arabica grown in the field under control (irrigation) and drought conditions using the pyrosequencing of RNA extracted from shoot apices and analysing the expression of 38 candidate genes. RESULTS: Pyrosequencing from shoot apices generated a total of 34.7 Mbp and 535,544 reads enabling the identification of 43,087 clusters (41,512 contigs and 1,575 singletons). These data included 17,719 clusters (16,238 contigs and 1,575 singletons) exclusively from 454 sequencing reads, along with 25,368 hybrid clusters assembled with 454 sequences. The comparison of DNA libraries identified new candidate genes (n = 20) presenting differential expression between IAPAR59 and Rubi and/or drought conditions. Their expression was monitored in plagiotropic buds, together with those of other (n = 18) candidates genes. Under drought conditions, up-regulated expression was observed in IAPAR59 but not in Rubi for CaSTK1 (protein kinase), CaSAMT1 (SAM-dependent methyltransferase), CaSLP1 (plant development) and CaMAS1 (ABA biosynthesis). Interestingly, the expression of lipid-transfer protein (nsLTP) genes was also highly up-regulated under drought conditions in IAPAR59. This may have been related to the thicker cuticle observed on the abaxial leaf surface in IAPAR59 compared to Rubi. CONCLUSIONS: The full transcriptome assembly of C. arabica, followed by functional annotation, enabled us to identify differentially expressed genes related to drought conditions. Using these data, candidate genes were selected and their differential expression profiles were confirmed by qPCR experiments in plagiotropic buds of IAPAR59 and Rubi under drought conditions. As regards the genes up-regulated under drought conditions, specifically in the drought-tolerant IAPAR59, several corresponded to orphan genes but also to genes coding proteins involved in signal transduction pathways, as well as ABA and lipid metabolism, for example. The identification of these genes should help advance our understanding of the genetic determinism of drought tolerance in coffee.

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RATIONALE: Amphibians can produce a large amount of bioactive peptides over the skin. In order to map the precise tissue localization of these compounds and evaluate their functions, mass spectrometry imaging (MSI) and gene expression studies were used to investigate a possible correlation between molecules involved in the antimicrobial defense mechanisms and anti-predatory behavior by Physalaemus nattereri. METHODS: Total skin secretion of P. nattereri was analyzed by classical Protein Chemistry and proteomic techniques. Intact inguinal macroglands were dissected from the rest of the skin and both tissues were analyzed by MSI and real-time polymerase chain reaction (RT-PCR) experiments. Peptides were primarily identified by de novo sequencing, automatic Edman degradation and cDNA data. RESULTS: Fifteen bradykinin (BK)-related peptides and two antimicrobial peptides were sequenced and mapped by MSI on the inguinal macrogland and the rest of P. nattereri skin. RT-PCR results revealed that BK-related peptide levels of expression were about 30,000 times higher on the inguinal macroglands than on the any other region of the skin, whilst antimicrobial peptide ions appear to be evenly distributed in both investigated regions. CONCLUSIONS: The presence of antimicrobial peptides in all investigated tissue regions is in accordance with the defensive role against microorganisms thoroughly demonstrated in the literature, whereas BK-related molecules are largely found on the inguinal macroglands suggesting an intriguing link between their noxious activities against potential predators of P. nattereri and the frog's deimatic behavior.

Assuntos

RESUMO

Drought is one of the most challenging agricultural issues limiting sustainable sugarcane production and, in some cases, yield losses caused by drought are nearly 50%. DREB proteins play vital regulatory roles in abiotic stress responses in plants. The transcription factor DREB2A interacts with a cis-acting DRE sequence to activate the expression of downstream genes that are involved in drought-, salt- and heat-stress response in Arabidopsis thaliana. In the present study, we evaluated the effects of stress-inducible over-expression of AtDREB2A CA on gene expression, leaf water potential (ΨL), relative water content (RWC), sucrose content and gas exchanges of sugarcane plants submitted to a four-days water deficit treatment in a rhizotron-grown root system. The plants were also phenotyped by scanning the roots and measuring morphological parameters of the shoot. The stress-inducible expression of AtDREB2A CA in transgenic sugarcane led to the up-regulation of genes involved in plant response to drought stress. The transgenic plants maintained higher RWC and ΨL over 4 days after withholding water and had higher photosynthetic rates until the 3rd day of water-deficit. Induced expression of AtDREB2A CA in sugarcane increased sucrose levels and improved bud sprouting of the transgenic plants. Our results indicate that induced expression of AtDREB2A CA in sugarcane enhanced its drought tolerance without biomass penalty.

Assuntos