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1.
Entropy (Basel) ; 26(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38539689

RESUMO

Since financial assets on stock exchanges were created, investors have sought to predict their future values. Currently, cryptocurrencies are also seen as assets. Machine learning is increasingly adopted to assist and automate investments. The main objective of this paper is to make daily predictions about the movement direction of financial time series through classification models, financial time series preprocessing methods, and feature selection with genetic algorithms. The target time series are Bitcoin, Ibovespa, and Vale. The methodology of this paper includes the following steps: collecting time series of financial assets; data preprocessing; feature selection with genetic algorithms; and the training and testing of machine learning models. The results were obtained by evaluating the models with the area under the ROC curve metric. For the best prediction models for Bitcoin, Ibovespa, and Vale, values of 0.61, 0.62, and 0.58 were obtained, respectively. In conclusion, the feature selection allowed the improvement of performance in most models, and the input series in the form of percentage variation obtained a good performance, although it was composed of fewer attributes in relation to the other sets tested.

2.
Sensors (Basel) ; 23(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299922

RESUMO

Biometrics-based authentication has become the most well-established form of user recognition in systems that demand a certain level of security. For example, the most commonplace social activities stand out, such as access to the work environment or to one's own bank account. Among all biometrics, voice receives special attention due to factors such as ease of collection, the low cost of reading devices, and the high quantity of literature and software packages available for use. However, these biometrics may have the ability to represent the individual impaired by the phenomenon known as dysphonia, which consists of a change in the sound signal due to some disease that acts on the vocal apparatus. As a consequence, for example, a user with the flu may not be properly authenticated by the recognition system. Therefore, it is important that automatic voice dysphonia detection techniques be developed. In this work, we propose a new framework based on the representation of the voice signal by the multiple projection of cepstral coefficients to promote the detection of dysphonic alterations in the voice through machine learning techniques. Most of the best-known cepstral coefficient extraction techniques in the literature are mapped and analyzed separately and together with measures related to the fundamental frequency of the voice signal, and its representation capacity is evaluated on three classifiers. Finally, the experiments on a subset of the Saarbruecken Voice Database prove the effectiveness of the proposed material in detecting the presence of dysphonia in the voice.


Assuntos
Disfonia , Voz , Humanos , Disfonia/diagnóstico , Acústica da Fala , Qualidade da Voz , Medida da Produção da Fala/métodos
3.
Sensors (Basel) ; 22(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35746343

RESUMO

Job Shop Scheduling is currently one of the most addressed planning and scheduling optimization problems in the field. Due to its complexity, as it belongs to the NP-Hard class of problems, meta-heuristics are one of the most commonly used approaches in its resolution, with Genetic Algorithms being one of the most effective methods in this category. However, it is well known that this meta-heuristic is affected by phenomena that worsen the quality of its population, such as premature convergence and population concentration in regions of local optima. To circumvent these difficulties, we propose, in this work, the use of a guidance operator responsible for modifying ill-adapted individuals using genetic material from well-adapted individuals. We also propose, in this paper, a new method of determining the genetic quality of individuals using genetic frequency analysis. Our method is evaluated over a wide range of modern GAs and considers two case studies defined by well-established JSSP benchmarks in the literature. The results show that the use of the proposed operator assists in managing individuals with poor fitness values, which improves the population quality of the algorithms and, consequently, leads to obtaining better results in the solution of JSSP instances. Finally, the use of the proposed operator in the most elaborate GA-like method in the literature was able to reduce its mean relative error from 1.395% to 0.755%, representing an improvement of 45.88%.


Assuntos
Algoritmos , Heurística , Humanos
4.
Sensors (Basel) ; 21(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208996

RESUMO

A large number of stroke survivors suffer from a significant decrease in upper extremity (UE) function, requiring rehabilitation therapy to boost recovery of UE motion. Assessing the efficacy of treatment strategies is a challenging problem in this context, and is typically accomplished by observing the performance of patients during their execution of daily activities. A more detailed assessment of UE impairment can be undertaken with a clinical bedside test, the UE Fugl-Meyer Assessment, but it fails to examine compensatory movements of functioning body segments that are used to bypass impairment. In this work, we use a graph learning method to build a visualization tool tailored to support the analysis of stroke patients. Called NE-Motion, or Network Environment for Motion Capture Data Analysis, the proposed analytic tool handles a set of time series captured by motion sensors worn by patients so as to enable visual analytic resources to identify abnormalities in movement patterns. Developed in close collaboration with domain experts, NE-Motion is capable of uncovering important phenomena, such as compensation while revealing differences between stroke patients and healthy individuals. The effectiveness of NE-Motion is shown in two case studies designed to analyze particular patients and to compare groups of subjects.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Movimento , Recuperação de Função Fisiológica , Extremidade Superior
5.
Sensors (Basel) ; 20(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971959

RESUMO

It is not uncommon for today's problems to fall within the scope of the well-known class of NP-Hard problems. These problems generally do not have an analytical solution, and it is necessary to use meta-heuristics to solve them. The Job Shop Scheduling Problem (JSSP) is one of these problems, and for its solution, techniques based on Genetic Algorithm (GA) form the most common approach used in the literature. However, GAs are easily compromised by premature convergence and can be trapped in a local optima. To address these issues, researchers have been developing new methodologies based on local search schemes and improvements to standard mutation and crossover operators. In this work, we propose a new GA within this line of research. In detail, we generalize the concept of a massive local search operator; we improved the use of a local search strategy in the traditional mutation operator; and we developed a new multi-crossover operator. In this way, all operators of the proposed algorithm have local search functionality beyond their original inspirations and characteristics. Our method is evaluated in three different case studies, comprising 58 instances of literature, which prove the effectiveness of our approach compared to traditional JSSP solution methods.

6.
BMC Plant Biol ; 19(1): 258, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208344

RESUMO

BACKGROUND: It has been previously shown that oligo-carrageenan (OC) kappa increases growth, photosynthesis and activities of enzymes involved in basal and secondary metabolisms in Eucalyptus globulus. However, it is not known whether OC kappa may induce the activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal and secondary metabolisms. RESULTS: E. globulus trees were sprayed on leaves with water (control) or with OC kappa 1 mg mL- 1, once a week, four times in total, and cultivated for 17 additional weeks (21 weeks in total). Treated trees showed a higher level of net photosynthesis than controls, beginning at week 3, a higher height, beginning at week 9, and those differences remained until week 21. In addition, treated trees showed an increase in the level of glucose beginning at week 1, trehalose at weeks 1-3, and in TOR-P level at week 1-2. On the other hand, transcripts encoding proteins involved in photosynthesis, and enzymes involved in glucose accumulation, C, N and S assimilation, and synthesis of secondary metabolites began at weeks 3-4 and with additional peaks at weeks 5-6, 8-11,13-14 and 17-19. Thus, OC kappa induced initial increases in glucose, trehalose and TOR-P levels that were followed by oscillatory increases in the level of transcripts coding for proteins involved in photosynthesis, and in basal and secondary metabolisms suggesting that initial increases in glucose, trehalose and TOR-P may trigger activation of gene expression. CONCLUSIONS: The stimulation of growth induced by OC kappa in E. globulus trees is due, at least in part, to activation of TOR pathway and the increase in expression of genes encoding proteins involved in photosynthesis and enzymes of basal metabolism.


Assuntos
Carragenina/farmacologia , Fotossíntese/efeitos dos fármacos , Metabolismo Basal/genética , Eucalyptus/genética , Eucalyptus/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucose/metabolismo , Fotossíntese/genética , Proteínas de Plantas/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Metabolismo Secundário/genética , Serina-Treonina Quinases TOR/metabolismo , Trealose/metabolismo
7.
Biol Res ; 52(1): 46, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434576

RESUMO

BACKGROUND: One of the most extreme environments on our planet is the Maritime Antarctic territory, due to its low-water availability, which restricts the development of plants. Sanionia uncinata Hedw. (Amblystegiaceae), the main colonizer of the Maritime Antarctic, has effective mechanisms to tolerate this environment. It has been described that the tolerance to desiccation is mediated by the hormone abscisic acid (ABA), antioxidants systems, accumulation of compatible solutes and proteins of the late embryogenesis abundant (LEA). However, to date, these mechanisms have not been described in S. uncinata. Therefore, in this work, we postulate that the tolerance to desiccation in the Antarctic moss S. uncinata is mediated by the accumulation of ABA, the osmolytes proline and glycine betaine, and dehydrins (an LEA class 11 proteins). To demonstrate our hypothesis, S. uncinata was subjected to desiccation for 24 h (loss in 95% of water content), and the effects on its physiological, photosynthetic, antioxidant and biochemical parameters were determined. RESULTS: Our results showed an accumulation of ABA in response to water loss, and the activation of protective responses that involves an increment in levels of proline and glycine betaine, an increment in the activity of antioxidant enzymes such as SOD, CAT, APX and POD, and the accumulation of dehydrins proteins. CONCLUSION: The results showed, suggest that S. uncinata is a  desiccation-tolerant moss, property mediated by high cellular plasticity regulated by ABA.


Assuntos
Antioxidantes/análise , Bryopsida/fisiologia , Dessecação , Fotossíntese/fisiologia , Adaptação Fisiológica , Regiões Antárticas , Bryopsida/química , Bryopsida/classificação , Fatores de Tempo
8.
Angew Chem Int Ed Engl ; 58(18): 5930-5935, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30675970

RESUMO

Asymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates, and reagents, even when targeting similar compounds. This approach slows down discovery and limits available chemical space. Introduced herein is a practical and versatile diazocompound and its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. The redox-active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect allowed the asymmetric cyclopropanation of various olefins, including unfunctionalized aliphatic alkenes, that enables the three-step total synthesis of (-)-dictyopterene A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally differentiated diazocompounds are viable and advantageous equivalents of single-carbon chirons.

9.
J Exp Bot ; 69(16): 4113-4126, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29860511

RESUMO

Phytoene synthase (PSY) is the first committed enzyme of the carotenoid biosynthesis pathway and the most important point of regulation. Carotenoids are precursors of abscisic acid (ABA), which mediates abiotic stress tolerance responses in plants. ABA activates the synthesis of its own precursors through induction of PSY expression. Carrot, a species that accumulates very high amounts of carotenoids in its reserve root, has two PSY paralog genes that are expressed differentially in the root. Here, we determined that DcPSY2 expression is induced by salt stress and ABA. A DcPSY2 promoter fragment was obtained and characterized. Bioinformatic analysis showed the presence of three ABA responsive elements (ABREs). Through overexpressing pPSY2:GFP in Nicotiana tabacum we determined that all three ABREs are necessary for the ABA response. In the carrot transcriptome, we identified three ABRE binding protein (DcAREB) transcription factor candidates that localized in the nucleus, but only one, DcAREB3, was induced under ABA treatment in carrot roots. We found that AREB transcription factors bind to the carrot DcPSY2 promoter and transactivate the expression of reporter genes. We conclude that DcPSY2 is involved in ABA-mediated salt stress tolerance in carrot through the binding of AREB transcription factors to its promoter.


Assuntos
Ácido Abscísico/metabolismo , Daucus carota/metabolismo , Geranil-Geranildifosfato Geranil-Geraniltransferase/biossíntese , Estresse Salino , Daucus carota/genética , Indução Enzimática , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas
10.
J Pediatr Hematol Oncol ; 40(6): 438-444, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29794643

RESUMO

Posttransplant lymphoproliferative disorder (PTLD) is a severe complication of solid organ transplantation. A common site for PTLD development is the gastrointestinal (GI) tract. The purpose of this study was to evaluate the incidence, clinical features, and overall survival of pediatric patients with GI-PTLD, and to assess whether major surgical interventions increased mortality. Records of pediatric transplant patients who developed GI-PTLD between January 2000 and June 2015 were retrospectively reviewed at our institution. Of 814 patients who received solid organ transplants, 34 (4%) developed GI-PTLD. Lung and multiorgan transplants had the highest incidence of GI-PTLD (both 11%). Patients often had multisite GI involvement (47%). Within the first year of transplantation, 38% of the 34 patients developed GI-PTLD. Of the patients with Epstein-Barr Virus-positive disease, 12/22 (55%) presented in the first 12 months of transplantation, compared with only 1/12 (8%) of the patients with Epstein-Barr Virus-negative disease (P=0.002). Major surgical interventions were required in 41% of patients; overall survival rate for these surgical patients was 71%, compared with 60% for patients not requiring major surgical interventions (P=0.49). Despite multimodal treatments, overall survival remains poor for patients with GI-PTLD; however, major surgical intervention did not significantly impact overall survival in this cohort.


Assuntos
Gastroenteropatias , Transtornos Linfoproliferativos , Transplante de Órgãos/efeitos adversos , Adolescente , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Gastroenteropatias/etiologia , Gastroenteropatias/mortalidade , Gastroenteropatias/patologia , Humanos , Incidência , Lactente , Recém-Nascido , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/mortalidade , Transtornos Linfoproliferativos/patologia , Masculino , Estudos Retrospectivos , Taxa de Sobrevida
11.
Biol Res ; 51(1): 48, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30428921

RESUMO

BACKGROUND: In field, C. quitensis is subjected to many abiotic extreme environmental conditions, such as low temperatures, high UV-B, salinity and reduced water potentials, but not metal or metalloid high concentrations in soil, however, other members of Caryophyllaceae family have tolerance to high concentrations of metals, this is the case of Silene genre. In this work, we hypothesize that C. quitensis have the same mechanisms of Silene to tolerate metals, involving accumulation and induction of antioxidant systems, sugar accumulation and the induction of thiols such as phytochelatins to tolerate. RESULTS: The results showing an effective antioxidant defensive machinery involving non-enzymatic antioxidants such as phenolics, GSH and ascorbic acid, in another hand, GSH-related oligomers (phytochelatins) and sugars was induced as a defensive mechanism. CONCLUSIONS: Colobanthus quitensis exhibits certain mechanisms to tolerate copper in vitro demonstrating its plasticity to tolerate several abiotic stress conditions.


Assuntos
Antioxidantes/fisiologia , Caryophyllaceae/metabolismo , Cobre/farmacologia , Fitoquelatinas/metabolismo , Açúcares/análise , Caryophyllaceae/química , Estresse Oxidativo/fisiologia , Fotossíntese , Açúcares/metabolismo
12.
Molecules ; 20(4): 5698-713, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25838172

RESUMO

Berry fruit consumption has become important in the promotion of human health, mainly due to their phenolic compounds, which have been associated with protection against different pathologies, as well as antimicrobial and other biological activities. Consequently, there has been a growing interest in identifying natural antioxidants and antimicrobials from these plants. This study aimed to characterize the phenolic chemical composition and anthocyanin profile of murta (Ugni molinae Turcz.) fruit, and to evaluate the antioxidant and antimicrobial activity of its extracts (ethanolic and methanolic). LC/MS of the ethanolic extracts showed the presence of three major compounds: caffeic acid 3-glu, quercetin-3-glu and quercetin, while in the methanolic acid extract they were cyanidin-3-glucoside, pelargonidin-3-arabinose and delphinidin-3-glucoside. The antioxidant activity of ethanolic extracts (DPPH· and ORAC assays) was higher than that of methanol acid extracts or purified anthocynins. Furthermore, the methanol acid extract showed an inhibitory activity against the bacteria E. coli and S. typhi similar to that of standard antibiotics. The results suggest that the antioxidant activity of the ethanolic extract is regulated by the high content of phenolic compounds and the fruit's characteristic color is due to the content of pelargonidin-3-arabinose and delphinidin-3-glucoside. The obtained results demonstrated the appreciable antioxidant and antibacterial activities, providing opportunities to explore murta extracts as biopreservatives.


Assuntos
Antioxidantes/isolamento & purificação , Fenóis/isolamento & purificação , Extratos Vegetais/química , Antocianinas/química , Antocianinas/isolamento & purificação , Antioxidantes/química , Antioxidantes/farmacologia , Escherichia coli/efeitos dos fármacos , Frutas/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Myrtaceae/química , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia
13.
Molecules ; 19(8): 12690-8, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25140447

RESUMO

Eucalyptus globulus trees treated with oligo-carrageenan (OC) kappa showed an increase in NADPH, ascorbate and glutathione levels and activation of the thioredoxin reductase (TRR)/thioredoxin (TRX) system which enhance photosynthesis, basal metabolism and growth. In order to analyze whether the reducing redox status and the activation of thioredoxin reductase (TRR)/thioredoxin (TRX) increased the level of growth-promoting hormones, trees were treated with water (control), with OC kappa, or with inhibitors of ascorbate synthesis, lycorine, glutathione synthesis, buthionine sulfoximine (BSO), NADPH synthesis, CHS-828, and thioredoxin reductase activity, auranofine, and with OC kappa, and cultivated for four additional months. Eucalyptus trees treated with OC kappa showed an increase in the levels of the auxin indole 3-acetic acid (IAA), gibberellin A3 (GA3) and the cytokinin trans-zeatin (t-Z) as well as a decrease in the level of the brassinosteroid epi-brassinolide (EB). In addition, treatment with lycorine, BSO, CHS-828 and auranofine inhibited the increase in IAA, GA3 and t-Z as well as the decrease in EB levels. Thus, the reducing redox status and the activation of TRR/TRX system induced by OC kappa increased the levels of IAA, GA3 and t-Z levels determining, at least in part, the stimulation of growth in Eucalyptus trees.


Assuntos
Carragenina/farmacologia , Eucalyptus/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxinas/metabolismo , Carragenina/química , Eucalyptus/efeitos dos fármacos , Giberelinas/biossíntese , Glutationa/metabolismo , NADP/metabolismo , Oxirredução/efeitos dos fármacos , Zeatina/biossíntese
14.
Plant Physiol ; 158(3): 1451-62, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22234999

RESUMO

To analyze the copper-induced cross talk among calcium, nitric oxide (NO), and hydrogen peroxide (H(2)O(2)) and the calcium-dependent activation of gene expression, the marine alga Ulva compressa was treated with the inhibitors of calcium channels, ned-19, ryanodine, and xestospongin C, of chloroplasts and mitochondrial electron transport chains, 3-(3,4-dichlorophenyl)-1,1-dimethylurea and antimycin A, of pyruvate dehydrogenase, moniliformin, of calmodulins, N-(6-aminohexyl)-5-chloro-1-naphtalene sulfonamide, and of calcium-dependent protein kinases, staurosporine, as well as with the scavengers of NO, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, and of H(2)O(2), ascorbate, and exposed to a sublethal concentration of copper (10 µm) for 24 h. The level of NO increased at 2 and 12 h. The first peak was inhibited by ned-19 and 3-(2,3-dichlorophenyl)-1,1-dimethylurea and the second peak by ned-19 and antimycin A, indicating that NO synthesis is dependent on calcium release and occurs in organelles. The level of H(2)O(2) increased at 2, 3, and 12 h and was inhibited by ned-19, ryanodine, xestospongin C, and moniliformin, indicating that H(2)O(2) accumulation is dependent on calcium release and Krebs cycle activity. In addition, pyruvate dehydrogenase, 2-oxoxglutarate dehydrogenase, and isocitrate dehydrogenase activities of the Krebs cycle increased at 2, 3, 12, and/or 14 h, and these increases were inhibited in vitro by EGTA, a calcium chelating agent. Calcium release at 2, 3, and 12 h was inhibited by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and ascorbate, indicating activation by NO and H(2)O(2). In addition, the level of antioxidant protein gene transcripts decreased with N-(6-aminohexyl)-5-chloro-1-naphtalene sulfonamide and staurosporine. Thus, there is a copper-induced cross talk among calcium, H(2)O(2), and NO and a calcium-dependent activation of gene expression involving calmodulins and calcium-dependent protein kinases.


Assuntos
Cobre/farmacologia , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Proteínas Quinases/metabolismo , Ulva/metabolismo , Antimicina A/metabolismo , Antimicina A/farmacologia , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Carbolinas/metabolismo , Carbolinas/farmacologia , Sobrevivência Celular , Cloroplastos/genética , Cloroplastos/metabolismo , Ciclo do Ácido Cítrico , Transporte de Elétrons , Ativação Enzimática , Regulação da Expressão Gênica de Plantas , Mitocôndrias/genética , Mitocôndrias/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Piperazinas/metabolismo , Piperazinas/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinases/genética , Rianodina/metabolismo , Rianodina/farmacologia , Fatores de Tempo , Ativação Transcricional , Ulva/efeitos dos fármacos , Ulva/genética
15.
Molecules ; 18(8): 8740-51, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23887716

RESUMO

Eucalyptus globulus (Myrtaceae) originated in Australia and has been introduced in countries with temperate weather in order to obtain wood for cellulose extraction and building purposes. In this work, we analyzed the potential stimulation of growth in height and trunk diameter as well as the content of holo-cellulose, α-cellulose (long cellulose chains), essential oils and polyphenolic compounds (PPCs) in E. globulus trees treated with oligo-carrageenans (OCs) kappa, lambda and iota, at 1 mg mL⁻¹, once a week, four times in total and then cultivated for three additional years without further treatment. Eucalyptus treated with OCs kappa, lambda and iota showed an increase in height, mainly with OCs kappa and iota by 58% and 47%, respectively, and in trunk diameter by 44% and 40%, respectively. In addition, OCs induced an increase in the contents of holo-cellulose and α-cellulose, mainly OCs kappa and iota which increased holo-cellulose by 8% and 5%, respectively, and α-cellulose by 16 and 13%, respectively. Moreover, OCs increased the content of essential oils, mainly OCs kappa and iota by 67% and 39%, respectively. Furthermore, OCs decreased the concentration of total phenolic compounds but differentially changed the concentration of several PPCs such as genistein, rutin, ellagic acid, morin, luteolin and quercetin with potential antimicrobial activities. Thus, marine algae OCs kappa, lambda and iota stimulate growth of E. globulus trees by enhancing height and trunk diameter as well as the content of α-cellulose, total essential oils, and some PPCs with potential antimicrobial activities.


Assuntos
Celulose/química , Eucalyptus/efeitos dos fármacos , Óleos Voláteis/química , Polifenóis/química , Carragenina/farmacologia , Eucalyptus/química , Eucalyptus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Folhas de Planta/efeitos dos fármacos
16.
Plants (Basel) ; 12(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653842

RESUMO

Background: Carotenoids, which are secondary metabolites derived from isoprenoids, play a crucial role in photo-protection and photosynthesis, and act as precursors for abscisic acid, a hormone that plays a significant role in plant abiotic stress responses. The biosynthesis of carotenoids in higher plants initiates with the production of phytoene from two geranylgeranyl pyrophosphate molecules. Phytoene synthase (PSY), an essential catalytic enzyme in the process, regulates this crucial step in the pathway. In Daucus carota L. (carrot), two PSY genes (DcPSY1 and DcPSY2) have been identified but only DcPSY2 expression is induced by ABA. Here we show that the ectopic expression of DcPSY2 in Nicotiana tabacum L. (tobacco) produces in L3 and L6 a significant increase in total carotenoids and chlorophyll a, and a significant increment in phytoene in the T1L6 line. Tobacco transgenic T1L3 and T1L6 lines subjected to chronic NaCl stress showed an increase of between 2 and 3- and 6-fold in survival rate relative to control lines, which correlates directly with an increase in the expression of endogenous carotenogenic and abiotic-related genes, and with ABA levels. Conclusions: These results provide evidence of the functionality of DcPSY2 in conferring salt stress tolerance in transgenic tobacco T1L3 and T1L6 lines.

17.
Sci Rep ; 13(1): 18355, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884637

RESUMO

Serum 25-hydroxyvitamin D concentrations deficiency is a growing health problem that affects a significant part of the world's population, with particularly negative consequences in children and older adults. Public health has prioritized healthy aging; thus, an investigation of the social determinants related to deficient and insufficient Serum 25-hydroxyvitamin D concentrations in older adults is needed to contribute to the implementation of comprehensive social programs focused on addressing those conditions adversely affecting the health of this group. This study was conducted using a sample of older adults (age ≥ 65 years, n = 1283) from the National Health Survey (NHS 2016-2017). The Average Marginal Effects of the social determinants of Serum 25-hydroxyvitamin D concentrations deficiency in older adults were predicted using a probit model in which the outcome variable assumed two values (deficiency or not deficiency), taking as independent variables those reported in previous studies. The model showed an adequate goodness of fit, Count R2 = 0.65, and the independent variables explained between 11% (Cox-Snell) and 14% (Nagelkerke) of the variance of the outcome variable. The social determinants associated with a greater likelihood of Serum 25-hydroxyvitamin D concentrations deficiency are the following conditions: women, people of native origin, urban dwellers, shorter sunlight exposure, and greater geographical latitude. Implications are discussed, and limitations are considered. Promotion and prevention programs should preferentially target older adults in the southernmost regions who live in urban areas, with a special focus on women. Due to the country's characteristics (17°-57° south latitude), it is necessary to review in future research the three zones shown in this study as relevant social determinants for the older adults living in them to generate inputs in formulating public health policies. The authorities must define the cut-off points for considering the difference between the country's ranges of Serum 25-hydroxyvitamin D concentrations insufficiency and deficiency.


Assuntos
Determinantes Sociais da Saúde , Deficiência de Vitamina D , Vitamina D , Idoso , Feminino , Humanos , Calcifediol/sangue , Estações do Ano , Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
18.
Plants (Basel) ; 11(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35161399

RESUMO

In this work, we have investigated the accumulation of ryanoids in different plant parts (leaves, stems and roots) of aeroponically grown Persea indica cloned trees (one-year-old cloned individuals) and a selected mature, wild tree. We tested the insect antifeedant (against Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi) and nematicidal (against Meloidogyne javanica) effects of ethanolic extracts from these different plant parts. The HPLC-MS analysis of P. indica extracts showed that mature tree (wild) leaves had two times more chemical diversity than stems. Aeroponic plants showed fewer differences in chemical diversity between leaves and stems, with the lowest diversity found in the roots. Ryanodane epiryanodol (1) was present in all the plant parts, with the mature stems (wild) containing the highest amount. The aeroponic stems also accumulated ryanoids including 1, cinnzeylanol (2) and cinnzeylanone (4). The insect Spodoptera littoralis was strongly affected by the stem extracts, while leaf extracts were moderately active. Based on predicted vs. real antifeedant values, we concluded that the ryanoid content (1 or a combination of 2, 4 and 1) explained the antifeedant effects of the stem extracts, while additional components contributed to the activity of the leaf extracts. Therefore, careful individual selection of P. indica seedlings should be carried out prior to proceeding with aeroponic cultivation in order to obtain ryanodane-rich stem or leaf extracts with strong antifeedant effects on S. littoralis.

19.
Physiol Biochem Zool ; 95(1): 66-81, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34875208

RESUMO

AbstractDuring the past 60 years, mammalian hibernation (i.e., seasonal torpor) has been interpreted as a physiological adaptation for energy economy. However, direct field comparisons of energy expenditure and torpor use in hibernating and active free-ranging animals are scarce. Here, we followed the complete hibernation cycle of a fat-storing hibernator, the marsupial Dromiciops gliroides, in its natural habitat. Using replicated mesocosms, we experimentally manipulated energy availability and measured torpor use, hibernacula use, and social clustering throughout the entire hibernation season. Also, we measured energy flow using daily food intake, daily energy expenditure (DEE), and basal metabolic rate (BMR) in winter. We hypothesized that when facing chronic caloric restriction (CCR), a hibernator should maximize torpor frequency to compensate for the energetic deficit, compared with individuals fed ad lib. (controls). However, being torpid at low temperatures could increase other burdens (e.g., cost of rewarming, freezing risks). Our results revealed that CCR animals, compared with control animals, did not promote heat conservation strategies (i.e., clustering and hibernacula use). Instead, they gradually increased torpor frequency and reduced DEE and, as a consequence, recovered weight at the end of the season. Also, CCR animals consumed food at a rate of 50.8 kJ d-1, whereas control animals consumed food at a rate of 98.4 kJ d-1. Similarly, the DEE of CCR animals in winter was 47.3±5.64 kJ d-1, which was significantly lower than control animals (DEE=88.0±5.84 kJ d-1). However, BMR and lean mass of CCR and control animals did not vary significantly, suggesting that animals maintained full metabolic capacities. This study shows that the use of torpor can be modulated depending on energy supply, thus optimizing energy budgeting. This plasticity in the use of heterothermy as an energy-saving strategy would explain the occurrence of this marsupial in a broad latitudinal and altitudinal range. Overall, this study suggests that hibernation is a powerful strategy to modulate energy expenditure in mammals from temperate regions.


Assuntos
Hibernação , Marsupiais , Torpor , Animais , Metabolismo Basal , Restrição Calórica , Metabolismo Energético , Estações do Ano
20.
Medwave ; 22(6)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35917236

RESUMO

Introduction The COVID- 19 pandemic discontinued sexual and reproductive health care in Chile and the world. The national focus on hospital care led primary care teams to respond in natural and diverse ways. Understanding the factors involved in this process may improve future responses from the judgment of good practices. Therefore, this study aimed to identify and systematize sexual and reproductive health initiatives raised by primary care teams in response to the COVID- 19 pandemic in Chile. Methods We systematically evaluated initiatives and practices in sexual and reproductive health in prima-ry care between June 2020 and November 2021. This study was developed in three methodological phases: a review of documents, a collection of experiences through an electronic instrument sent to the 29 health services in Chile, and in-depth interviews. According to best practice criteria, mapping and characterizing the initiatives and critical discourse analysis of narratives and interviews were carried out. Results Forty-one initiatives from 19 health services were identified, mainly from the South Central macro zone and urban areas. In these areas, care was recognized. These practices were relevant, aligned with their objectives, rapidly implemented, and used novel strategies through new technologies. However, these initiatives had little intercultural relevance or evaluation. Perceived success was related to motivation, leadership, and institutional and community resilience. The adaptability of initiatives emerged as a new need and criterion of analysis. Conclusion The lessons learned from these initiatives invite us to consider health care teams' mental health, their relationship with the community, the use of new technologies, the evaluation of practices considering satisfaction, cross- cutting approaches, and their adaptability. In all, these aspects may improve primary care response in sexual and reproductive health to new crises.


Introducción La pandemia de COVID- 19 ha implicado la discontinuidad de atención en salud sexual y reproductiva en Chile y el mundo. El foco en la contención hospitalaria de la pandemia llevó a los equipos de atención primaria a responder de manera innata y diversa. Por lo tanto, el objetivo de este estudio fue identificar y sistematizar iniciativas de salud sexual y reproductiva planteadas por equipos de atención primaria en respuesta a la pandemia COVID- 19 en Chile, con el fin de comprender y aprender de los factores involucrados en esta, para mejorar futuras respuestas desde la lógica de buenas prácticas. Metodología Estudio de sistematización de iniciativas y prácticas en salud sexual y reproductiva en atención primaria, entre junio de 2020 y noviembre de 2021. Fue desarrollado en tres fases metodológicas: revisión de documentos, recolección de experiencias a través de instrumento electrónico enviado a los 29 servicios de salud de Chile y entrevistas de profundización. Se realizó un mapeo y caracterización de las iniciativas y análisis crítico de discurso de narrativas y entrevistas, según criterios de buenas prácticas. Resultados Se identificaron 41 iniciativas de 19 servicios de salud, principalmente de la Macro Zona Centro- sur, urbanas y de reorganización de atención. Fueron prácticas pertinentes, alineadas a sus objetivos, con procesos rápidos de implementación, estrategias innovadoras, alto uso de tecnologías con escasa pertinencia intercultural ni evaluación. El éxito percibido se relacionó con motivación, liderazgo, y resiliencia institucional y comunitaria. La adaptabilidad de las iniciativas emergió como una nueva necesidad y criterio. Conclusión Son importantes los aprendizajes emanados de las iniciativas que invitan a considerar la salud mental de los equipos, su relación con la comunidad, el uso de tecnologías, la evaluación de las prácticas considerando satisfacción, enfoques transversales y la adaptabilidad de estas, para mejorar la respuesta de atención primaria en salud sexual y reproductiva ante nuevas crisis.


Assuntos
COVID-19 , Chile , Humanos , Pandemias , Atenção Primária à Saúde , Saúde Reprodutiva
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