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1.
Sci Data ; 11(1): 746, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982093

RESUMO

Many research articles have explored the impact of surgical interventions on voice and speech evaluations, but advances are limited by the lack of publicly accessible datasets. To address this, a comprehensive corpus of 107 Spanish Castilian speakers was recorded, including control speakers and patients who underwent upper airway surgeries such as Tonsillectomy, Functional Endoscopic Sinus Surgery, and Septoplasty. The dataset contains 3,800 audio files, averaging 35.51 ± 5.91 recordings per patient. This resource enables systematic investigation of the effects of upper respiratory tract surgery on voice and speech. Previous studies using this corpus have shown no relevant changes in key acoustic parameters for sustained vowel phonation, consistent with initial hypotheses. However, the analysis of speech recordings, particularly nasalised segments, remains open for further research. Additionally, this dataset facilitates the study of the impact of upper airway surgery on speaker recognition and identification methods, and testing of anti-spoofing methodologies for improved robustness.


Assuntos
Fala , Voz , Humanos , Período Pós-Operatório , Tonsilectomia , Masculino , Feminino , Período Pré-Operatório , Adulto
2.
Bioengineering (Basel) ; 10(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38002440

RESUMO

End-to-end deep learning models have shown promising results for the automatic screening of Parkinson's disease by voice and speech. However, these models often suffer degradation in their performance when applied to scenarios involving multiple corpora. In addition, they also show corpus-dependent clusterings. These facts indicate a lack of generalisation or the presence of certain shortcuts in the decision, and also suggest the need for developing new corpus-independent models. In this respect, this work explores the use of domain adversarial training as a viable strategy to develop models that retain their discriminative capacity to detect Parkinson's disease across diverse datasets. The paper presents three deep learning architectures and their domain adversarial counterparts. The models were evaluated with sustained vowels and diadochokinetic recordings extracted from four corpora with different demographics, dialects or languages, and recording conditions. The results showed that the space distribution of the embedding features extracted by the domain adversarial networks exhibits a higher intra-class cohesion. This behaviour is supported by a decrease in the variability and inter-domain divergence computed within each class. The findings suggest that domain adversarial networks are able to learn the common characteristics present in Parkinsonian voice and speech, which are supposed to be corpus, and consequently, language independent. Overall, this effort provides evidence that domain adaptation techniques refine the existing end-to-end deep learning approaches for Parkinson's disease detection from voice and speech, achieving more generalizable models.

3.
Front Aging Neurosci ; 15: 1194203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744400

RESUMO

Introduction: Proteolytic processing of amyloid protein precursor by ß-site secretase enzyme (BACE1) is dependent on the cellular lipid composition and is affected by endomembrane trafficking in dementia and Alzheimer's disease (AD). Stearoyl-CoA desaturase 1 (SCD1) is responsible for the synthesis of fatty acid monounsaturation (MUFAs), whose accumulation is strongly associated with cognitive dysfunction. Methods: In this study, we analyzed the relationship between BACE1 and SCD1 in vivo and in vitro neurodegenerative models and their association in familial AD (FAD), sporadic AD (SAD), and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) using microscopy, biochemical, and mass SPECT approach. Results: Our findings showed that BACE1 and SCD1 immunoreactivities were increased and colocalized in astrocytes of the hippocampus in a rat model of global cerebral ischemia (2-VO). A synergistic effect of double BACE1/SCD1 silencing on the recovery of motor and cognitive functions was obtained. This neuroprotective regulation involved the segregation of phospholipids (PLs) associated with polyunsaturated fatty acids in the hippocampus, cerebrospinal fluid, and serum. The double silencing in the sham and ischemic groups was stronger in the serum, inducing an inverse ratio between total phosphatydilcholine (PC) and lysophosphatidylcholine (LPC), represented mainly by the reduction of PC 38:4 and PC 36:4 and an increase in LPC 16:0 and LPC 18:0. Furthermore, PC 38:4 and PC:36:4 levels augmented in pathological conditions in in vitro AD models. BACE1 and SCD1 increases were confirmed in the hippocampus of FAD, SAD, and CADASIL. Conclusion: Therefore, the findings suggest a novel convergence of BACE-1 and SCD1 in neurodegeneration, related to pro-inflammatory phospholipids.

4.
Diagnostics (Basel) ; 13(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37189482

RESUMO

Due to the primary affection of the respiratory system, COVID-19 leaves traces that are visible in plain chest X-ray images. This is why this imaging technique is typically used in the clinic for an initial evaluation of the patient's degree of affection. However, individually studying every patient's radiograph is time-consuming and requires highly skilled personnel. This is why automatic decision support systems capable of identifying those lesions due to COVID-19 are of practical interest, not only for alleviating the workload in the clinic environment but also for potentially detecting non-evident lung lesions. This article proposes an alternative approach to identify lung lesions associated with COVID-19 from plain chest X-ray images using deep learning techniques. The novelty of the method is based on an alternative pre-processing of the images that focuses attention on a certain region of interest by cropping the original image to the area of the lungs. The process simplifies training by removing irrelevant information, improving model precision, and making the decision more understandable. Using the FISABIO-RSNA COVID-19 Detection open data set, results report that the opacities due to COVID-19 can be detected with a Mean Average Precision with an IoU > 0.5 (mAP@50) of 0.59 following a semi-supervised training procedure and an ensemble of two architectures: RetinaNet and Cascade R-CNN. The results also suggest that cropping to the rectangular area occupied by the lungs improves the detection of existing lesions. A main methodological conclusion is also presented, suggesting the need to resize the available bounding boxes used to delineate the opacities. This process removes inaccuracies during the labelling procedure, leading to more accurate results. This procedure can be easily performed automatically after the cropping stage.

5.
World Allergy Organ J ; 16(4): 100763, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37091550

RESUMO

Background: Dupilumab is a treatment approved for uncontrolled moderate-to-severe atopic dermatitis (AD). Tropical and developing countries such as Colombia have characteristics that may impact the natural history of AD and access to medical treatments. In that sense, we aimed to describe the effectiveness and safety of dupilumab in adults with moderate to severe AD in a Colombian multicenter cohort. Methods: Multicenter descriptive study that included patients who started treatment between March 2018 and May 2020 in 6 centers. Disease severity was assessed using the following: Scoring Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), Patient Oriented Eczema Measure (POEM), and Dermatology Life Quality Index (DLQI). These measurements were collected according to availability at baseline, 3-5 months, 6-12 months, and more than 12 months. Days of sick leave, hospitalizations, and AD flares before and after dupilumab treatment were reported. Adverse events (AEs) were recorded during follow-up. Results: Ninety-three patients were included, with a median age of 32 years (IQR: 24.0; 40.0) and a disease evolution time of 21 years (IQR: 16.0; 29.5). 88.2% had at least 1 allergic disease other than AD. An improvement greater than or equal to 75% EASI was observed in 41.7% of patients at 3-5 months, in 73.7% of patients at 6-12 months, and in 75.0% of patients after 12 months. For those reporting SCORAD and POEM, the median percent change ([IQR], n) from baseline in SCORAD was -67.1 ([-79.2; -54.2], n = 16), -70.5 ([-85.8; -47.9], n = 36) and -66.7 ([-77.3; -51.0], n = 13); and POEM, -58.6 ([-66.4; -55.5], n = 4), -73.0 ([-86.5; -66.7], n = 16) and -87.3 ([-93.4; -69.6], n = 8), respectively. Before initiation of dupilumab treatment, 82 (88.2%) patients reported at least 1 flare of AD in the past 12 months. During the follow-up period, 30 (32.3%) patients reported at least 1 exacerbation or flare. Twelve patients (12.9%) presented an AE and 3 (3.2%) patients discontinued dupilumab for this cause. Conclusions: Dupilumab was effective and safe for the treatment of moderate to severe AD in point-of-care settings, with results similar to randomized controlled and other real-life studies. These positive results are still maintained even though a high number of patients had short interruptions in the use of dupilumab due to administrative problems.

6.
Sci Rep ; 11(1): 13799, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226609

RESUMO

The research was conducted to determine the effects of cutting interval and fertilization on the nutritional quality, nutrient uptake, and biomass production of King grass. The experimental design was a randomized complete block, using 4 blocks and 8 treatments per block; treatments consisted of 4 ages of cutting (30, 45, 60, and 90 days), with fertilization and without fertilization. The results showed increases of up to 72,000 kg ha-1 year-1 of dry matter (DM) when fertilization was implemented. There was a significant reduction in with an increase in the cutting days (12.70-6.53% protein). Fiber increased (48.79-72.99% NDF) when fertilization treatments were included and cutting days increased. The elements that were included in fertilization (N, P, K) showed a higher foliar content and also presented a reduction in foliar content with growth of the plant. Treatments with fertilization showed a nutrient uptake increase for all the elements up to 60 days, where a reduction in uptake capacity was observed. King grass is a plant with a high nutrient uptake capacity and, therefore, with high biomass and nutrient production. This is an advantage since it can be used in multiple applications, such as animal feed, biofuel production, and as a substrate for biodigestion, among others.


Assuntos
Biomassa , Fertilização , Valor Nutritivo/efeitos dos fármacos , Poaceae/crescimento & desenvolvimento , Ração Animal , Animais , Biocombustíveis , Ingestão de Alimentos/efeitos dos fármacos , Nutrientes , Pennisetum/efeitos dos fármacos , Pennisetum/crescimento & desenvolvimento , Poaceae/efeitos dos fármacos
7.
Front Aging Neurosci ; 12: 587989, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281599

RESUMO

Evidence suggests that extracellular vesicles (EVs) act as mediators and biomarkers of neurodegenerative diseases. Two distinct forms of Alzheimer disease (AD) are known: a late-onset sporadic form (SAD) and an early-onset familial form (FAD). Recently, neurovascular dysfunction and altered systemic immunological components have been linked to AD neurodegeneration. Therefore, we characterized systemic-EVs from postmortem SAD and FAD patients and evaluated their effects on neuroglial and endothelial cells. We found increase CLN-5 spots with vesicular morphology in the abluminal portion of vessels from SAD patients. Both forms of AD were associated with larger and more numerous systemic EVs. Specifically, SAD patients showed an increase in endothelial- and leukocyte-derived EVs containing mitochondria; in contrast, FAD patients showed an increase in platelet-derived EVs. We detected a differential protein composition for SAD- and FAD-EVs associated with the coagulation cascade, inflammation, and lipid-carbohydrate metabolism. Using mono- and cocultures (endothelium-astrocytes-neurons) and human cortical organoids, we showed that AD-EVs induced cytotoxicity. Both forms of AD featured decreased neuronal branches area and astrocytic hyperreactivity, but SAD-EVs led to greater endothelial detrimental effects than FAD-EVs. In addition, FAD- and SAD-EVs affected calcium dynamics in a cortical organoid model. Our findings indicate that the phenotype of systemic AD-EVs is differentially defined by the etiopathology of the disease (SAD or FAD), which results in a differential alteration of the NVU cells implied in neurodegeneration.

8.
Biochim Biophys Acta Mol Basis Dis ; 1866(8): 165797, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32302650

RESUMO

Sporadic Alzheimer's disease (SAD) is the most common form of dementia, and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most frequent hereditary ischemic small vessel disease of the brain. Relevant biomarkers or specific metabolic signatures could provide powerful tools to manage these diseases. Therefore, the main goal of this study was to compare the postmortem frontal cortex gray matter, white matter and cerebrospinal fluid (CSF) between a cognitively healthy group and CADASIL and SAD groups. We evaluated 352 individual lipids, belonging to 13 lipid classes/subclasses, using mass spectrometry, and the lipid profiles were subjected to multivariate analysis to discriminate between the dementia groups (CADASIL and SAD) and healthy controls. The main lipid molecular species showing greater discrimination by partial least squares-discriminant analysis (PLS-DA) and a higher significance multivariate correlation (sMC) index were as follows: phosphatidylserine (PS) PS(44:7) and lysophosphatidylethanolamine (LPE) LPE(18:2) in gray matter (GM); phosphatidylethanolamine (PE) PE(32:2) and phosphatidylcholine PC PC(44:6) in white matter (WM), and ether PE (ePE) ePE(38:2) and ether PC (ePC) ePC(34:3) in CSF. Common phospholipid molecular species were obtained in both dementias, such as PS(44:7) and lyso PC (LPC) LPC(22:5) in GM, PE(32:2) in WM and phosphatidic acid (PA) PA(38:5) and PC(42:7) in CFS. Our exploratory study suggests that phospholipids (PLs) involved in neurotransmission alteration, connectivity impairment and inflammation response in GM, WM and CSF are a transversal phenomenon affecting dementias such as CADASIL and SAD independent of the etiopathogenesis, thus providing a possible common prodromal phospholipidic biomarker of dementia.


Assuntos
Doença de Alzheimer/metabolismo , CADASIL/metabolismo , Lobo Frontal/metabolismo , Substância Cinzenta/metabolismo , Tecido Parenquimatoso/metabolismo , Fosfolipídeos/metabolismo , Substância Branca/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Autopsia , Biomarcadores/análise , CADASIL/diagnóstico , CADASIL/patologia , Estudos de Casos e Controles , Análise Discriminante , Feminino , Lobo Frontal/patologia , Substância Cinzenta/patologia , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Tecido Parenquimatoso/patologia , Fosfolipídeos/química , Fosfolipídeos/classificação , Fosfolipídeos/isolamento & purificação , Substância Branca/patologia
9.
Heliyon ; 6(2): e03312, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32072041

RESUMO

The aim of this work was to determine the effect of temperature on the formation of acrylamide in cocoa beans during drying treatment by an experimental and computational study, in order to assess the presence of this neoformed compound from postharvest stage. The computational study was conducted on the reaction between fructose, glyoxal from glucose, and on asparagine at the M06-2X/6-31+G(d,p) level, under cocoa bean drying conditions at 323.15 to 343.15 K. The proposed reaction for acrylamide formation consisted of seven steps, which required to progress a via cyclic transition state of the four members. In addition, step III (decarboxylation) was considered to be the rate-determining step. Glucose followed an E1-like elimination and fructose exhibited an E1cb-like elimination. Computational model showed that the reaction of acrylamide formation was favored by fructose rather than glucose. The content of reducing sugars, asparagine and acrylamide in fermented and dried cocoa from two subregions of Antioquia-Colombia, as well as roasted cocoa, were evaluated by UHPLC-C-CAD and UHPLC-QqQ. The concentrations of monosaccharides measured at the end of the fermentation and drying process of cocoa nibs showed greater decreases in the levels of fructose as compared to glucose, supporting the main model hypothesis. Acrylamide formation only occurred in Bajo Cauca due to the presence of both precursors and fast drying time (72 h). Finally, it was possible to find the conditions to which acrylamide can be formed from the drying process and not only from roasting, information that can be used for future control strategies.

10.
J Food Sci Technol ; 57(1): 210-221, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975724

RESUMO

The profile of reducing sugars developed during each stage of the postharvest of cocoa beans is an important quality index; these sugars are found to be one of the main precursors of flavor and neoformed compounds. However, its quantification after extraction from different parts of the bean is a challenge due to the complexity of the matrix. The primary aim of this study was to track the formation of reducing sugars and mannitol in samples obtained from various steps of the fermentation and drying processes of cocoa beans by validating a rapid matrix-corrected chromatographic method utilizing a corona-charged aerosol detector for improved sensitivity. The analytes were extracted from ground cocoa beans by solid phase extraction without a defatting step (20 mg raw fermented and 10 mg dried). The experimental variables influencing the effective detection were evaluated at different temperatures and signal filtering levels. Method validation studies showed an average recovery between 77.8 and 120% for fermented cocoa and between 79.6 and 117.7% for dried cocoa. A linear response was achieved for fructose, glucose, sucrose, and mannitol for a concentration range of 0.1-40 mg/L, and maltose showed linearity in the range of 0.1-70 mg/L. Regression coefficients (R) were 0.9991, 0.9993, 0.9992, 0.9995 and 0.9994, respectively. This method was successfully applied to a clone mix of cocoa from Antioquia, Colombia, to confirm the hydrolysis reaction of sucrose into glucose and fructose during fermentation and drying. A quality indicator of an efficient postharvest process in this study was determined to be a glucose percentage of 0.66% w/w and a fructose percentage of 1.46% w/w, which were higher than the values reported by other studies.

11.
IEEE Access ; 8: 226811-226827, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34786299

RESUMO

Current standard protocols used in the clinic for diagnosing COVID-19 include molecular or antigen tests, generally complemented by a plain chest X-Ray. The combined analysis aims to reduce the significant number of false negatives of these tests and provide complementary evidence about the presence and severity of the disease. However, the procedure is not free of errors, and the interpretation of the chest X-Ray is only restricted to radiologists due to its complexity. With the long term goal to provide new evidence for the diagnosis, this paper presents an evaluation of different methods based on a deep neural network. These are the first steps to develop an automatic COVID-19 diagnosis tool using chest X-Ray images to differentiate between controls, pneumonia, or COVID-19 groups. The paper describes the process followed to train a Convolutional Neural Network with a dataset of more than 79, 500 X-Ray images compiled from different sources, including more than 8, 500 COVID-19 examples. Three different experiments following three preprocessing schemes are carried out to evaluate and compare the developed models. The aim is to evaluate how preprocessing the data affects the results and improves its explainability. Likewise, a critical analysis of different variability issues that might compromise the system and its effects is performed. With the employed methodology, a 91.5% classification accuracy is obtained, with an 87.4% average recall for the worst but most explainable experiment, which requires a previous automatic segmentation of the lung region.

12.
Heliyon ; 5(5): e01650, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31193315

RESUMO

The aim of this study was to compare the quality of a mixture of cocoa harvested and fermented in three subregions of Antioquia (Colombia), from the chemometric profile based on multivariate statistical analysis. A mixture of clones CCN-52, ICS-1, FLE-2, and FEC-2 harvested in Bajo Cauca, Uraba and Magdalena Medio were subjected to a spontaneous fermentation. The characterization of raw and well-fermented cocoa was performed through 38 parameters, and results were compared by a Principal Component Analysis (PCA) and a Cluster Analysis (CA), followed by a Principal Factors Analysis (PFA- CA). The CA showed that there are differences among subregions only in raw cocoa from Bajo Cauca. PCA allowed identifying the variability between raw and fermented cocoa in a representative way and these results were consistent with the chemical profile. Besides, the number of parameters to differentiate raw cocoa from different subregions was reduced (11-13 parameters) and it was possible to characterize well fermented cocoa with only 10 parameters of 38. PFA-CA consolidated in three factors a grouping to identify the cocoa quality according to the process or interest of the sensory or functional properties. Factor 1 (cocoa quality indicators with functional properties), Factor 2 (indicators of quality of the beginning of fermentation) and Factor 3 (indicators of quality of well-fermented cocoa) each one with a weight of 39, 35 and 26 respectively.

13.
Rev Alerg Mex ; 66(1): 18-26, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31013403

RESUMO

BACKGROUND: Several reports show deficiencies in the knowledge of physicians about the diagnostic criteria and the treatment of anaphylaxis, a condition that can have fatal consequences. OBJECTIVE: To evaluate the knowledge of physicians in Colombia on the fundamental aspects of anaphylaxis in diagnosis and treatment. METHODS: Analytical cross-sectional study, carried out through a survey of 11 questions that evaluate clinical aspects of anaphylaxis, addressed to general practitioners and specialists in different health areas resident in Colombia. The analysis of the results was based on the correct answers. For approval, a score higher than 70% was needed. RESULTS: A total of 447 non-allergic doctors analyzed were included, of which only 110 (24.6%) approved the questionnaire in both the questions aimed at the diagnosis and in the treatment of anaphylaxis. Among the factors that were associated with the failure of the survey were the age of the doctor (p <0.01) and work at the first level of care (p <0.01). CONCLUSIONS: Like previous studies, knowledge in the diagnosis and treatment of anaphylaxis is scarce among Colombian physicians. The factors associated with said result are potentially modifiable.


Antecedentes: Varios reportes evidencian la necesidad de mayor conocimiento de los médicos acerca de los criterios diagnósticos y de manejo de la anafilaxia, condición que puede tener consecuencias fatales. Objetivo: Evaluar en Colombia los conocimientos de los médicos no alergólogos, acerca de los aspectos fundamentales de la anafilaxia en el diagnóstico oportuno y el tratamiento. Métodos: Estudio transversal realizado mediante una encuesta de 11 preguntas relativas a aspectos clínicos de la anafilaxia, dirigida a médicos generales y especialistas residentes en Colombia. El análisis de los resultados se hizo con base en las respuestas correctas. El corte de aprobación se estableció en > 70 %. Resultados: Se incluyeron 447 médicos no alergólogos, de los cuales solo 110 (24.6 %) aprobaron el cuestionario tanto en los aspectos diagnóstico como terapéuticos. Entre los factores asociados con reprobar la encuesta se identificó mayor edad (p < 0.01) y trabajar en el primer nivel de atención (p < 0.01). Conclusiones: Similar a lo reportado en otros estudios, el conocimiento en el diagnóstico y tratamiento de la anafilaxia fue deficiente entre los médicos colombianos. Los factores asociados con estos resultados son potencialmente modificables.


Assuntos
Anafilaxia/diagnóstico , Anafilaxia/terapia , Competência Clínica , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Colômbia , Estudos Transversais , Feminino , Humanos , Masculino , Medicina
14.
Univ. sci ; 24(1): 33-48, Jan-Apr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1014752

RESUMO

Abstract Tithonia diversifolia is a robust shrub that has high ecological plasticity and adaptability, high capacity of nutrient absorption and high nutrient contents. These characteristics make Tithonia diversifolia be considered as a multi-purpose plant, such as for animal feed, soil decontamination and soil restorer. Likewise, it is a plant with high ecological plasticity and adaptability. The study of the nutrient absorption and the fertilization represent an important advance in the development of productive systems focused on maximizing forage productivity, which guarantees the soil sustainability. Based on this, a split plot design was conducted to study the effects of different levels of fertilization. The results showed an impact of the elements and levels of fertilization on the nutrient absorption capacity, finding that the elements that were incorporated in the fertilization increase the foliar contents and the nutrient absorption in the plant.


Resumen Tithonia diversifolia es un arbusto robusto que tiene alta plasticidad ecológica y adaptabilidad, alta capacidad de absorción de nutrientes y alto contenido de nutrientes. Estas características hacen que Tithonia diversifolia sea considerada una planta multipropósito, tanto para alimento animal como para descontaminación y restauración del suelo. El estudio de la absorción de nutrientes y la fertilización representa un avance importante en el desarrollo de sistemas productivos enfocados en la maximización de la productividad de forraje, lo cual garantiza la sostenibilidad del suelo. Con base en esto, se llevó a cabo un diseño experimental de parcelas divididas con el fin de estudiar los efectos de diferentes niveles de fertilización. Los resultados mostraron un impacto de los elementos y los niveles de fertilización en la capacidad de absorción de nutrientes; se encontró que los elementos que fueron incorporados en la fertilización incrementan los contenidos foliares y la absorción de nutrientes en la planta.


Resumo Tithonia diversifolia é um arbusto robusto que tem alta plasticidade ecológica e adaptabilidade, alta capacidade de absorção de nutrientes e alto conteúdo de nutrientes. Estas características fazem com que Tithonia diversifolia seja considerada uma planta multipropósito, tanto para alimento animal como para descontaminação e restauração do solo. O estudo da absorção de nutrientes e da fertilização representa um avance importante no desenvolvimento de sistemas produtivos enfocados na otimizacao da produtividade de forragem, o que garante a sustentabilidade do solo. Baseado em esto, se realizou um desenho experimental de parcelas divididas com a finalidade de estudar os efeitos de diferentes níveis de fertilização. Os resultados mostraram um impacto dos elementos e dos níveis de fertilização na capacidade de absorção de nutrientes. Se encontrou que os elementos que foram incorporados na fertilização incrementam os conteúdos foliares e a absorção de nutrientes na planta.

15.
Phys Chem Chem Phys ; 21(7): 3752-3760, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30702098

RESUMO

An exploration of the antioxidant power of curcumin, demethoxycurcumin, and bisdemethoxycurcumin, three natural antioxidants found in Curcuma longa, is reported in this work. We exhaust all structural possibilities leading to intramolecular hydrogen bonding and evaluate 15 isomers in total. Calculations were carried out in the gas phase and in the presence of solvents (water, to mimic biological media, and ethanol, to reproduce experimental assays) following the hydrogen atom transfer (HAT) and single electron transfer (SET) mechanisms. CH3OH-O hydrogen bonds are directly related to the antioxidant power via both mechanisms. We provide evidence to explain the experimental observations and to understand the fundamental factors driving antioxidant activity from a molecular perspective. Noticeably, the solvent enhances the antioxidant power in every case. All structures considered here are predicted to have better antioxidant abilities than phenol, and come very close to or surpass vitamin E.


Assuntos
Curcumina/análogos & derivados , Curcumina/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Curcumina/química , Diarileptanoides , Ligação de Hidrogênio/efeitos dos fármacos
16.
Food Chem ; 280: 231-239, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30642491

RESUMO

Cocoa has been widely discussed as a bioactive food rich in sensory stimulation and health benefits. However, no information has been provided concerning phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in cocoa. These compounds are of interest because they play a role in the regulation of immune function. The present study included 31 cocoa clones. The PhytoPs and PhytoFs were quantified by UHPLC-QqQ-MS/MS. The total PhytoPs and PhytoFs contents ranged from 221.46 to 1589.83 ng g-1 and from 1.18 to 13.13 ng g-1, respectively. The profiles of the PhytoPs and PhytoFs identified in the cocoa beans showed significant differences among the clones analysed. The results indicate that dry fermented cocoa beans are rich in PhytoPs and PhytoFs, which may represent an additional benefit of the consumption of foods derived from cocoa.


Assuntos
Cacau/química , Ácidos Graxos Insaturados/análise , Furanos/análise , Espectrometria de Massas em Tandem/métodos , Cacau/metabolismo , Cromatografia Líquida de Alta Pressão , Estresse Oxidativo
17.
J Sci Food Agric ; 99(5): 2194-2204, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30315579

RESUMO

BACKGROUND: In Colombia, agro-industrial residues represent an enormous economic and environmental problem, which could be reduced if different techniques for the addition of value to such residues were implemented by this industrial sector. One of the fruits with the highest export rates is Physalis peruviana (goldenberry); however, this fruit is generally marketed without its calyx, generating a large amount of residues. To develop a strategy to add value to these residues, it is essential to know their chemical composition. RESULTS: In the present work, phytoprostanes (PhytoPs) - new active oxylipins - have been detected for the first time in Physalis peruviana calyces by ultra-high performance liquid chromatography triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS), F1t -phytoprostanes and D1t -phytoprostanes being the predominant and minor classes, respectively. In addition, we were able to characterize the phenolic compounds profile of this matrix using LC-IT-DAD-MS/MS, describing six phenolic derivatives for the first time therein. CONCLUSIONS: This study increases our knowledge of the chemical composition of the calyces of this fruit and thereby supports the recycling of this class of residue. Consequently, goldenberry calyces could be used as phytotherapeutic, nutraceutic, or cosmetic ingredients for the development of diverse natural products. © 2018 Society of Chemical Industry.


Assuntos
Oxilipinas/química , Fenóis/química , Physalis/química , Extratos Vegetais/química , Biotecnologia/economia , Cromatografia Líquida de Alta Pressão , Flores/química , Oxilipinas/isolamento & purificação , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem
19.
Iatreia ; 31(2): 166-179, ene.-jun. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-953916

RESUMO

RESUMEN La anafilaxia se define como una reacción de hipersensibilidad, sistémica, de instauración rápida y potencialmente fatal, con manifestaciones clínicas y severidad variable, que resulta de la liberación súbita de mediadores de mastocitos y basófilos. El diagnóstico de esta entidad es fundamentalmente clínico, basándose en los patrones de manifestación y la exposición a un posible detonante. Actualmente varios estudios indican deficiencias en la identificación y manejo de esta enfermedad, lo que genera un riesgo elevado de mortalidad. En esta revisión presentamos puntos prácticos del manejo e identificamos las principales consideraciones a tener en cuenta en el primer nivel de atención.


SUMMARY Anaphylaxis is defined as a systemic, rapid onset, and potentially fatal hypersensitivity reaction, with variable clinical manifestations and severity resulting from the sudden reléase of mast cell and basophil mediators. The diagnosis of this entity is fundamentally clinical, based on the patterns of manifestation and the exposure to a possible trigger. Currently several studies indicate deficiencies in the identification and management of this disease, which generates an increase in mortality. In this review we present practical points of management and identify the main considerations to be taken into account in the first level care.


Assuntos
Humanos , Literatura de Revisão como Assunto , Anafilaxia , Hipersensibilidade
20.
Food Chem ; 256: 181-187, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606436

RESUMO

Lutein, a xanthophyll, is associated to decreased risk of age-related macular degeneration, atherosclerosis and other diseases (Bovier et al., 2013; El-raey, Ibrahim, & Eldahshan, 2013). When lutein is extracted, it becomes highly unstable, reducing its functionality as an antioxidant. The aim of this research was to improve the stability of lutein using maltodextrin, arabic gum and a modified starch, to obtain micro-particles using spray-drying. Each of the formulations was characterized in terms of yield, encapsulation efficiency, particle size distribution, water activity and moisture content. The formulations with arabic gum (100%) and arabic gum:maltodextrin:modified starch (33.3:33.3:33.3%), with encapsulation efficiencies of 91.94 ±â€¯6.88 and 65.72 ±â€¯0.93%, respectively, were selected to study stability at 45 °C and 75% RH (relative humidity). Based on our results, encapsulation could be considered as an alternative for the generation of high value-added functional ingredients that can be used in different industries.


Assuntos
Antioxidantes/química , Composição de Medicamentos , Luteína/química , Dessecação , Estabilidade de Medicamentos , Goma Arábica/química , Tamanho da Partícula , Polissacarídeos/química , Amido/química
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