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Ganoderma lucidum (a mushroom used in traditional Chinese medicine) compounds may attenuate ageing-related physiological changes and restore normal immunity. However, studies on the physiological effects of Ganoderma lucidum dry extract food supplements are few. Therefore, here, we aimed to investigate the effects of Ganoderma lucidum dry extract food supplement on the lymphocyte function of older women. This was a double-blind clinical trial (n 60) with a final 39 older volunteers, divided into two groups Ganoderma lucidum (n 23) and placebo (n 16). The Ganoderma lucidum group received 2000 mg/d of Ganoderma lucidum dry extract for 8 weeks. We used flow cytometry to determine the lymphocyte profile. CD4+ lymphocyte gene expression was evaluated by real-time polymerase chain reaction. We observed that in the Ganoderma lucidum group, concanavalin A stimulation increased lymphocyte proliferation. Further, we observed an increase in expression of Forkhead box P3, transforming growth factor-beta, IL-10, IL-6, retinoic acid receptor-related orphan receptor gamma, GATA-binding protein 3 and interferon gamma genes in the Ganoderma lucidum group. Furthermore, in the Ganoderma lucidum group, ionomycin and phorbol 12-myristate 13-acetate stimulation led to decrease in Th17+ cells and increase in Th2+ cells. Thus, in older women, Ganoderma lucidum regulates T lymphocyte function leading to a predominant anti-inflammatory action but does not induce T lymphocyte proliferation through CD28 signalling pathway.
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BACKGROUND: The success of collaborative quality improvement (QI) projects in healthcare depends on the context and engagement of health teams; however, the factors that modulate teams' motivation to participate in these projects are still unclear. The objective of the current study was to explore the barriers to and facilitators of motivation; the perspective was health professionals in a large project aiming to implement evidence-based infection prevention practices in intensive care units of Brazilian hospitals. METHODS: This qualitative study was based on content analysis of semistructured in-depth interviews held with health professionals who participated in a collaborative QI project named "Improving patient safety on a large scale in Brazil". In accordance with the principle of saturation, we selected a final sample of 12 hospitals located throughout the five regions of Brazil that have implemented QI; then, we conducted videoconference interviews with 28 health professionals from those hospitals. We encoded the interview data with NVivo software, and the interrelations among the data were assessed with the COM-B model. RESULTS: The key barriers identified were belief that improvement increases workload, lack of knowledge about quality improvement, resistance to change, minimal involvement of physicians, lack of supplies, lack support from senior managers and work overload. The primary driver of motivation was tangible outcomes, as evidenced by a decrease in infections. Additionally, factors such as the active participation of senior managers, teamwork, learning in practice and understanding the reason for changes played significant roles in fostering motivation. CONCLUSION: The motivation of health professionals to participate in collaborative QI projects is driven by a variety of barriers and facilitators. The interactions between the senior manager, quality improvement teams, and healthcare professionals generate attitudes that modulate motivation. Thus, these aspects should be considered during the implementation of such projects. Future research could explore the cost-effectiveness of motivational approaches.
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Motivación , Mejoramiento de la Calidad , Humanos , Brasil , Personal de Salud , Investigación CualitativaRESUMEN
Propolis is a natural resinous product produced by Apis mellifera bees from the exudates of various plants. The color of propolis (green) is a consequence of its botanical origin, as bees collect young tissues and leaves of Baccaris dracunculifolia. This study evaluated the chemical composition and extraction kinetics of essential oils obtained from Brazilian green propolis by hydrodistillation. Hydrodistillation was performed for 360â min and analyzed at different times (30, 60, 120, 240, and 360â min), allowing the calculation of the accumulated content (% w/w) and the identification of the essential oil chemical profile. The GC/FID and GC/MS analysis led to the annotation of 60 compounds with estragole (13.30 %), benzyl propanoate (14.59 %), and (E)-nerolidol (13.57 %) as the main compounds. The optimum conditions for extraction of phenylpropanoids (PP), hydrocarbons (HD), monoterpenes (MT), and oxygenated monoterpenes (OMT) are between 30 and 120â min. In comparison, sesquiterpenes (ST) and oxygenated sesquiterpenes (OST) are extracted more efficiently between 240 and 360â min. The optimal extraction speed determination is essential for industrial-scale processing to obtain components such as sesquiterpenes, which have a high economic value in the cosmetic/perfumery and pharmaceutical industries.
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Endophytic fungi live asymptomatically inside vegetal tissues, and such uncommon habitat contributes to their exceptional chemical diversity. Isolating natural products from endophytic fungi could fail due to silent biosynthetic gene clusters under ordinary inâ vitro culture conditions, and co-culturing has been assayed to trigger their metabolism. We carried out single and dual cultures with 13 endophyte strains isolated from Euphorbia umbellata leaves. Multivariate statistics applied to untargeted metabolomics compared the chemical profiles of all endophyte cultures. PCA analysis guided the selection of the Aspergillus pseudonomiae J1 - Porogramme brasiliensis J9 dual culture for its most significant chemical differentiation: Five compounds were putatively annotated in the J1-J9 culture according to UHPLC-HRMS data, kojic acid, haliclonol and its diastereoisomer, caffeic acid, and 2-(3,4-dihydroxyphenyl)acetaldehyde. Analysis by PLS-DA using VIP score showed that kojic acid displayed the most significative importance in discriminating single and dual J1-J9 cultures.
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Endófitos , Euphorbia , Metabolómica , Euphorbia/química , Euphorbia/microbiología , Endófitos/química , Endófitos/metabolismo , Endófitos/aislamiento & purificación , Hojas de la Planta/microbiología , Hojas de la Planta/química , Cromatografía Líquida de Alta Presión , Pironas/química , Pironas/aislamiento & purificación , Pironas/metabolismo , Aspergillus/metabolismo , Aspergillus/química , Aspergillus/aislamiento & purificaciónRESUMEN
The present study aimed to analyze the prevalence of childhood obesity in Brazil and compare it between boys and girls. This systematic review was conducted and reported according to the guidelines outlined in the PRISMA statement. A systematic search of electronic databases, including PubMed, LILACS, and SciELO, was performed in November 2021. Studies that met the following criteria were included: (i) original quantitative studies regardless of their design; (ii) childhood obesity was clearly defined; (iii) prevalence of childhood obesity was reported or it was possible to extract from tables or figures in the text; and (iv) eligible population included children under 12 years of age. A total of 112 articles were included in the systematic review. The prevalence of childhood obesity in Brazil was of 12.2%, being 10.8% in girls and 12.3% in boys. In addition, wide heterogeneity in the childhood obesity prevalence was observed between the states, since it was 2.6% in Pará, while it was 15.8% in Rondônia. Thus, the importance of urgently implementing measures to prevent and treat childhood obesity should be emphasized aiming to reduce obese children and adolescents and future health problems in adult life resulting from this cardiovascular risk factor.
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Obesidad Infantil , Masculino , Adulto , Adolescente , Femenino , Niño , Humanos , Obesidad Infantil/epidemiología , Prevalencia , BrasilRESUMEN
The current industrial and human activities scenario has accelerated the widespread use of endocrine-disrupting compounds (EDCs), which can be found in everyday products, including plastic containers, bottles, toys, cosmetics, etc., but can pose a severe risk to human health and the environment. In this regard, fungal bioremediation appears as a green and cost-effective approach to removing pollutants from water resources. Besides, immobilizing fungal cells onto nanofibrous membranes appears as an innovative strategy to improve remediation performance by allowing the adsorption and degradation to occur simultaneously. Herein, we developed a novel nanostructured bioremediation platform based on polyacrylonitrile nanofibrous membrane (PAN NFM) as supporting material for immobilizing an endophytic fungus to remove bisphenol A (BPA), a typical EDC. The endophytic strain was isolated from Handroanthus impetiginosus leaves and identified as Phanerochaete sp. H2 by molecular methods. The successful assembly of fungus onto the PAN NFM surface was confirmed by scanning electron microscopy (SEM). Compared with free fungus cells, the PAN@H2 NFM displayed a high BPA removal efficiency (above 85%) at an initial concentration of 5 ppm, suggesting synergistic removal by simultaneous adsorption and biotransformation. Moreover, the biotransformation pathway was investigated, and the chemical structures of fungal metabolites of BPA were identified by ultra-high performance liquid chromatography - high-resolution mass (UHPLC-HRMS) analysis. In general, our results suggest that by combining the advantages of enzymatic activity and nanofibrous structure, the novel platform has the potential to be applied in the bioremediation of varied EDCs or even other pollutants found in water resources.
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Nanofibras , Tabebuia , Contaminantes Químicos del Agua , Humanos , Nanofibras/química , Fenoles/análisis , Hongos , Contaminantes Químicos del Agua/análisisRESUMEN
This study aimed to evaluate the physiological and reproductive parameters of Nelore cows under various microclimatic conditions. The experiment was performed in Central Brazil, which has a tropical climate with dry winters and rainy summers. The experimental groups were divided into an area with shading (5.8 trees/ha; n = 42) and an area with little shading (0.4 trees/ha; n = 42). The physiological (heart rate, respiratory rate, rectal temperature, surface body temperature, and vaginal temperature) and reproductive (estrus detection, conception rate, and rate of pregnancy loss) parameters were then assessed. The rectal temperature (p = 0.002); surface body temperature on the flanks, forehead, and shoulder (p < 0.001); and vaginal temperature (p < 0.001) of cows in the group with shading were significantly lower than those of cows in the group without shading. Estrus was higher (p = 0.08) in the shaded group; however, no effect was observed on conception and pregnancy loss rates. In conclusion, shading (5.8 trees/ha) provided better thermal comfort for Nelore animals in the tropical climatic region. However, this did not affect their performance after fixed-time artificial insemination.
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Fertilización , Reproducción , Embarazo , Femenino , Bovinos , Animales , Índice de Embarazo , Temperatura , Estro , Árboles , Inseminación Artificial/veterinaria , Sincronización del Estro , Progesterona/farmacologíaRESUMEN
Human pegivirus-1 (HPgV-1) is a member of the Flaviviridae family and the Pegivirus genus. Despite having been discovered 25 years ago, there is still much to know regarding HPgV-1 clinical impact, as this virus is currently not associated with any pathology. Yet, HPgV-1 prevalence and molecular characterization are still unknown in many countries, including Portugal. To fill in this knowledge gap, this study aimed to determine the occurrence and molecular characterization of HPgV-1 in a group of healthy blood donors from the north of Portugal. Blood samples from 465 Portuguese blood donors were collected from a major Hospital Center in the north of Portugal. RNA was extracted and an initial nested RT-PCR was performed targeting the conserved 5'-untranslated region region of the HPgV-1 genome. A second nested RT-PCR targeting the E2 region was performed for genotyping. Only one sample tested positive for HPgV-1 RNA, resulting in a prevalence of approximately 0.22%. Phylogenetic analyses confirmed the characterization as genotype 2, the most prevalent in Europe.
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Infecciones por Flaviviridae , Flaviviridae , Virus GB-C , Donantes de Sangre , Flaviviridae/genética , Infecciones por Flaviviridae/epidemiología , Virus GB-C/genética , Voluntarios Sanos , Humanos , Filogenia , Portugal/epidemiología , Prevalencia , ARN , ARN Viral/genética , Viremia/epidemiologíaRESUMEN
Schinus essential oils were tentatively identified by GC×GC/TOFMS, which revealed a greater number of compounds than previously reported. Eighty-six, seventy-two, and eighty-eight components were identified in Schinus lentiscifolius, Schinus molle and Schinus terebinthifolius essential oils, respectively. Compound separation due to 2 D selectivity was observed. Phytotoxic effects of Schinus essential oils were assessed on germination and initial growth of Arabidopsis thaliana. All essential oils in all tested quantities (5â µL, 10â µL, 15â µL, 20â µL, and 25â µL) affected germination rate, speed of accumulated germination, and root and shoot length of A.â thaliana. Considering the mode of action of the essential oils, no differences were observed on expression of the genes ANP1 and CDK B1;1 in A.â thaliana, which was analyzed by RT-qPCR. Results suggest that phytotoxic effects of Schinus essential oils seem to be explained by cellular damage rather than by induction of stress-inducible genes.
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Alcaloides , Anacardiaceae , Arabidopsis , Aceites Volátiles , Aceites Volátiles/toxicidad , Aceites Volátiles/química , Schinus , Anacardiaceae/químicaRESUMEN
This updated review article covers the literature between 2011 and 2021 on the antibacterial activity of EOs against the main bacteria that cause caries and periodontal diseases. The criteria to classify the inâ vitro antibacterial activity of EOs is updated and the most promising results are addressed.
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Aceites Volátiles , Antibacterianos/farmacología , Bacterias , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacologíaRESUMEN
A virus minimally contains a nucleic acid genome packaged by a protein coat. The genome and capsid together are known as the nucleocapsid, which has an envelope containing a lipid bilayer (mainly phospholipids) originating from host cell membranes. The viral envelope has transmembrane proteins that are usually glycoproteins. The proteins in the envelope bind to host cell receptors, promoting membrane fusion and viral entry into the cell. Virus-infected host cells exhibit marked increases in glutamine utilization and metabolism. Glutamine metabolism generates ATP and precursors for the synthesis of macromolecules to assemble progeny viruses. Some compounds derived from glutamine are used in the synthesis of purines and pyrimidines. These latter compounds are precursors for the synthesis of nucleotides. Inhibitors of glutamine transport and metabolism are potential candidate antiviral drugs. Glutamine is also an essential nutrient for the functions of leukocytes (lymphocyte, macrophage, and neutrophil), including those in virus-infected patients. The increased glutamine requirement for immune cell functions occurs concomitantly with the high glutamine utilization by host cells in virus-infected patients. The development of antiviral drugs that target glutamine metabolism must then be specifically directed at virus-infected host cells to avoid negative effects on immune functions. Therefore, the aim of this review was to describe the landscape of cellular glutamine metabolism to search for potential candidates to inhibit glutamine transport or glutamine metabolism.
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Antivirales/farmacología , Glutamina/metabolismo , Redes y Vías Metabólicas/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Línea Celular Tumoral , Interacciones Huésped-Patógeno , Humanos , Neoplasias/metabolismo , Neoplasias/virología , Virulencia/efectos de los fármacos , Virus/efectos de los fármacos , Virus/patogenicidadRESUMEN
NEW FINDINGS: What is the central question of this study? Is lymphocyte DNA methylation differentially modulated by resistance training and aerobic exercise in older women? What is the main finding and its importance? The practice of resistance training led to an increased global DNA methylation in lymphocytes. The exercise-induced increase of inflammatory genes methylation may be associated with immune function impairment during ageing. ABSTRACT: Ageing-induced increase in inflammatory gene expression through a reduction in DNA methylation might contribute to chronic diseases. Regular physical exercise practices, in turn, are associated with a decrease in the incidence of inflammatory diseases. We herein evaluated the effects of three exercise modalities on lymphocyte global and gene-specific (interferon γ (IFN-γ) and interleukin 17A (IL-17A) DNA methylation in aged women (68 ± 7.5 years). This cross-sectional study included 86 women, divided into four groups according to the physical exercise practice: 20 were practicing resistance training (RT); 24 were practicing water aerobics exercise (W); 22 were practicing water aerobics and resistance exercise (RWT), and 20 did not practice any physical exercise (CON). We evaluated volunteer functional capability using the Timed Up and Go (TUG) test, global lymphocyte DNA methylation by enzyme-linked immunosorbent assay, IFN-γ and IL-17A methylation by qPCR and CD4+ IFN-γ+ and CD4+ IL-17+ cell percentage by flow cytometry. The three physically exercised groups performed functional capability tests in a shorter period and showed a higher global lymphocyte DNA methylation and methylated CpGs of IL-17A and IFN-γ promoter regions than the control group. The practice of resistance training (RT and RWT groups) lead to high global DNA methylation. The combination of resistance training and aerobic exercise led to the increase of lymphocyte IL-17A and IFN-γ gene methylation induced by each separately. However, the percentage of IFN-γ+ and IL-17+ cells was lower only in the RT group. The exercise-induced increase of inflammatory-gene methylation may be associated with gene expression changes and immune function impairment during ageing.
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Interferón gamma , Interleucina-17 , Anciano , Estudios Transversales , Metilación de ADN , Ejercicio Físico , Femenino , Humanos , Interferón gamma/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Linfocitos/metabolismoRESUMEN
Endophytes are microorganisms that live inside vegetal tissues without causing any loss to the host plant. They display wide biosynthetic capacity when producing several bioactive secondary metabolites, whose induction could be related to activation of genes, which might be silent or expressed depending on the geographic characteristics from where the endophytic was isolated. The extraordinary richness of the Brazilian biodiversity has encouraged several research groups in the endophytic bioprospecting. This review covers natural products reported by studies on from the Brazilian endophytic fungi cultures and classified them into three chemical classes (terpenes, phenolic, and nitrogen-containing compounds). For discussion purposes, Principal Component Analysis (PCA) was used as an unsupervised explorative method to evaluate the chemical variation in the Brazilian endophyte dataset. In addition, the dendrogram from the Hierarchical Clustering Analysis (HCA) confirmed the PCA results, and HCA could identify some main endophytic clusters. Our analysis clarified how the secondary metabolites were distributed in the different Brazilian endophyte strains, and this information will be a reliable guide that will support researchers to design microbial culture strategies.
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Endófitos , Hongos , Bioprospección , Brasil , Endófitos/genética , Hongos/genética , PlantasRESUMEN
Hundreds of millions of people worldwide are affected by Chagas' disease caused by Trypanosoma cruzi. Since the current treatment lack efficacy, specificity, and suffers from several side-effects, novel therapeutics are mandatory. Natural products from endophytic fungi have been useful sources of lead compounds. In this study, three lactones isolated from an endophytic strain culture were in silico evaluated for rational guidance of their bioassay screening. All lactones displayed inâ vitro activity against T.â cruzi epimastigote and trypomastigote forms. Notably, the IC50 values of (+)-phomolactone were lower than benznidazole (0.86 vs. 30.78â µM against epimastigotes and 0.41 vs. 4.88â µM against trypomastigotes). Target-based studies suggested that lactones displayed their trypanocidal activities due to T.â cruzi glyceraldehyde-3-phosphate dehydrogenase (TcGAPDH) inhibition, and the binding free energy for all three TcGAPDH-lactone complexes suggested that (+)-phomolactone has a lower score value (-3.38), corroborating with IC50 assays. These results highlight the potential of these lactones for further anti-T.â cruzi drug development.
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Productos Biológicos/farmacología , Euphorbia/química , Lactonas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Productos Biológicos/química , Productos Biológicos/metabolismo , Euphorbia/metabolismo , Lactonas/química , Lactonas/metabolismo , Modelos Moleculares , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Filogenia , Tripanocidas/química , Tripanocidas/metabolismoRESUMEN
Objective: Telemedicine is seen as an important tool to face contemporary health challenges. The factors that help improve quality in these services must be studied. The objective of this work was to assess the quality of telehealth primary care services offered in the State of Minas Gerais -Brazil, based on the ISO 13131 standard. Methods: This cross-sectional analytical study with a quantitative approach was conducted in the cities in the state of Minas Gerais that use telehealth services. A stratified sample composed of 385 cities was used. A questionnaire, based on ISO 13131 on the quality of telehealth services, was prepared, used, and verified for its consistency. Quality levels in telehealth were built from the data. To analyze the quality of care, data from the Ministry of Health's quality improvement program were used, involving 366 surveyed cities. Logistic regression was performed to verify the association between quality of telehealth and quality of care. Results: The research identified that 64% of the cities had records of telehealth activities, and 51% of cities had high quality telehealth services. There was no association between quality of telehealth and quality of care; only the dimensions of Quality and Risk Management were associated with quality of care. Conclusion: The developed instrument enabled the quality of telehealth actions to be verified. The State of Minas Gerais has high-quality telehealth services.
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Atención Primaria de Salud , Telemedicina , Brasil , Estudios Transversales , Humanos , Encuestas y CuestionariosRESUMEN
Studies on the rearing of ewe lambs in the Cerrado are scarce, so the objective was to evaluate the effects of protein-energy supplementation with 1.6 and 2.4% BW on the productive and reproductive performance of ewe lambs raised on pastures of Brachiaria brizantha cv. Marandu. Twenty-four Texel ewe lambs, with a mean age of 5 months, were distributed in two treatments with provision of energy protein supplementation at levels of 1.6 and 2.4% BW, formulated for average daily gains of 150 and 200 g/day for ewe lambs weighing 20 kg, respectively. The experimental delineation adopted was the completely randomized design, with fifteen repetitions per treatment. The performance of the ewe lambs was evaluated by weight at the beginning and end of the breeding season (BS), average daily gain (ADG), and total weight gain (TWG). The count of fecal eggs was performed monthly. The evaluation of the ewe lambs reproductive organs took place at 8 months of age. The fertility of the ewe lambs was detected by transrectal ultrasonography at the end of the BS. The supplementation level of 2.4% BW was higher for ADG and TWG; however, it did not influence the other performance characteristics. There was no effect of supplementation on the reproductive characteristics, parasite load, and nutrients of the pasture. Pasture nutrients were influenced by the month of use. Supplementation levels were not effective to ensure the reproductive success of 8-month-old ewe lambs.
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Óvulo , Fitomejoramiento , Animales , Suplementos Dietéticos , Femenino , Reproducción , Ovinos , Oveja DomésticaRESUMEN
Neutrophils were traditionally considered as short-lived cells with abundant secretory and protein synthetic activity. Recent studies, however, indicate neutrophils are in reality a heterogeneous population of cells. Neutrophils differentiate from pluripotent stem cells in the bone marrow, and can further mature in the blood stream and can have different phenotypes in health and disease conditions. Neutrophils undergo primary functions such as phagocytosis, production of reactive oxygen species (ROS), release of lipid mediators and inflammatory proteins (mainly cytokines), and apoptosis. Neutrophils stimulate other neutrophils and trigger a cascade of immune and inflammatory responses. The underpinning intracellular metabolisms that support these neutrophil functions are herein reported. It has been known for many decades that neutrophils utilize glucose as a primary fuel and produce lactate as an end product of glycolysis. Neutrophils metabolize glucose through glycolysis and the pentose- phosphate pathway (PPP). Mitochondrial glucose oxidation is very low. The PPP provides the reduced nicotinamide adenine dinucleotide phosphate (NADPH) for the NADPH-oxidase (NOX) complex activity to produce superoxide from oxygen. These cells also utilize glutamine and fatty acids to produce the required adenosine triphosphate (ATP) and precursors for the synthesis of molecules that trigger functional outcomes. Neutrophils obtained from rat intraperitoneal cavity and incubate for 1 hour at 37°C metabolize glutamine at higher rate than that of glucose. Glutamine delays neutrophil apoptosis and maintains optimal NOX activity for superoxide production. Under limited glucose provision, neutrophils move to fatty acid oxidation (FAO) to obtain the required energy for the cell function. FAO is mainly associated with neutrophil differentiation and maturation. Hypoxia, hormonal dysfunction, and physical exercise markedly change neutrophil metabolism. It is now become clear that neutrophil metabolism underlies the heterogeneity of neutrophil phenotypes and should be intense focus of investigation.
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Glucosa/metabolismo , Glutamina/metabolismo , NADPH Oxidasas/metabolismo , Neutrófilos/metabolismo , Animales , Hipoxia de la Célula/fisiología , Citocinas/metabolismo , Ácidos Grasos/metabolismo , Hormonas/farmacología , Humanos , Mitocondrias/metabolismo , NADP/metabolismo , Neutrófilos/citología , Neutrófilos/enzimología , Neutrófilos/inmunología , Condicionamiento Físico Animal/fisiología , Especies Reactivas de Oxígeno/metabolismo , Superóxidos/metabolismoRESUMEN
Arbuscular mycorrhizal fungi (AMF) absorb and translocate nutrients from soil to their host plants by means of a wide network of extraradical mycelium (ERM). Here, we assessed whether nitrogen-fixing rhizobia can be transferred to the host legume Glycine max by ERM produced by Glomus formosanum isolate CNPAB020 colonizing the grass Urochloa decumbens. An H-bridge experimental system was developed to evaluate the migration of ERM and of the GFP-tagged Bradyrhizobium diazoefficiens USDA 110 strain across an air gap compartment. Mycorrhizal colonization, nodule formation in legumes, and occurrence of the GFP-tagged strain in root nodules were assessed by optical and confocal laser scanning microscopy. In the presence of non-mycorrhizal U. decumbens, legume roots were neither AMF-colonized nor nodulated. In contrast, G. formosanum ERM crossing the discontinuous compartment connected mycorrhizal U. decumbens and G. max roots, which showed 30-42% mycorrhizal colonization and 7-11 nodules per plant. Fluorescent B. diazoefficiens cells were detected in 94% of G. max root nodules. Our findings reveal that, besides its main activity in nutrient transfer, ERM produced by AMF may facilitate bacterial translocation and the simultaneous associations of plants with beneficial fungi and bacteria, representing an important structure, functional to the establishment of symbiotic relationships.
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Fabaceae , Micorrizas , Bacterias , Nitrógeno , Raíces de Plantas , SimbiosisRESUMEN
We aimed to evaluate the bioherbicide potential of Eucalyptus saligna leaf litter essential oil, its fractions and major compounds. Six essential oil fractions were obtained by preparative thin-layer chromatography and analyzed by gas chromatography/mass spectrometry. Effects of the oil, its fractions and major compounds (1,8-cineole and/or α-pinene) diluted in aqueous solution were assessed on germination and seedling growth. Recipient species were Lactuca sativa (model), Amaranthus viridis (weed), Eragrostis plana (weed), and Paspalum notatum (forage). The essential oil was more phytotoxic on A. viridis and L. sativa, followed by E. plana, and caused no effects on P. notatum. Amaranthus viridis was inhibited by all treatments, mainly the essential oil, α-pinene and fraction 6, whereas E. plana was more affected by the oil fractions. Results revealed the species-specific phytotoxic effects of E. saligna essential oil, indicating its potential use for controlling A. viridis and E. plana. Phytotoxic effects of essential oils or their components should not be generalized, as effects may change according to recipient species.
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Amaranthus/efectos de los fármacos , Eragrostis/efectos de los fármacos , Eucalyptus/química , Herbicidas/farmacología , Aceites Volátiles/farmacología , Hojas de la Planta/química , Herbicidas/química , Herbicidas/aislamiento & purificación , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Control de MalezasRESUMEN
Labdane diterpenes and their derivatives have shown remarkable biological activities and are useful as chiral building blocks for the synthesis of a variety of bioactive compounds. There is great interest in developing biocatalyst technology to achieve regio- and stereoselective hydroxylation of unactivated C-H bonds in complex natural products, since the functionalization of unactivated C-H bonds generally requires hard reaction conditions and highly reactive oxidizing agents, which are limited regarding the control of regio- and stereoselectivity. Filamentous fungi are efficient biocatalysts capable of catalyzing a wide variety of hydroxylation reactions, and the use of whole cell biocatalysts provides advantages regarding cofactor regeneration and is much less expensive. Therefore, the goal of this study was to select biocatalysts to develop biotransformation processes that can be scalable under mild reaction conditions for hydroxylation of a labdane diterpene, 3ß-acetoxy-copalic acid, which contains the trans-decalin moiety and a side chain dienic system appropriate for the preparation of a variety of compounds. Biotransformation processes were carried out and five filamentous fungi were selected as capable of producing hydroxylated diterpenes at positions C-3, C-6, C-7 and C-18 of the trans-decalin moiety and C-13 of the side chain dienic system. Hydroxylation reactions occurred with regio- and stereoselectivity by using some fungi that produced only the 6α, 7α and 13α-hydroxyl derivatives. The chemical structures of the hydroxylated diterpenes were determined from spectrometric and spectroscopic data, and the relative stereochemistry of stereogenic centers was established from coupling constants, by NOE-diff experiments and/or by computational calculations.