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1.
Sports Biomech ; : 1-18, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37462321

RESUMO

Neuromuscular fatigue (NMF) reduces the musculoskeletal system's ability to produce force during activities like running. Analysis of motor behaviour's regularity may identify motor system deficits caused by fatigue. The present study investigated whether the NMF of lower limb extensors alters the regularity of running movement and whether this possible effect remains over time. Crossover study with two randomised conditions: NMF and control. Twelve healthy young males participated in this study. Hip, knee, and ankle angles (sagittal plane) and centre of mass (CoM) linear accelerations were assessed during treadmill running at self-selected speed in four assessment conditions: Baseline (pre-NMF), and after NMF (NMF condition) or after rest (control), at the 1st (Time_1), 10th (Time_10) and 20th (Time_20) minutes. Kinematics regularity was measured as Sample Entropy. Repeated measures ANOVAs were used (α = 0.05). NMF reduced regularity of lower limb joints during running, and these effects remained up to 20 minutes. No changes were observed in the CoM accelerations' regularity. The regularity reductions may be an adaptive solution for the motor system to maintain the task performance. The measure of regularity of the lower limb joints' motion is sensitive to NMF and can identify states with deficits in muscles' force production capacity in running.

2.
Phys Chem Chem Phys ; 24(44): 27121-27127, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342321

RESUMO

During the last decade, X-ray free-electron lasers (XFELs) have enabled the study of light-matter interaction under extreme conditions. Atoms which are subject to XFEL radiation are charged by a complex interplay of (several subsequent) photoionization events and electronic decay processes within a few femtoseconds. The interaction with molecules is even more intriguing, since intricate nuclear dynamics occur as the molecules start to dissociate during the charge-up process. Here, we demonstrate that by analyzing photoelectron angular emission distributions and kinetic energy release of charge states of ionic molecular fragments, we can obtain a detailed understanding of the charge-up and fragmentation dynamics. Our novel approach allows for gathering such information without the need of complex ab initio modeling. As an example, we provide a detailed view on the processes happening on a femtosecond time scale in oxygen molecules exposed to intense XFEL pulses.

3.
BMC Public Health ; 22(1): 2067, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36368962

RESUMO

BACKGROUND: South African universities face a challenge of low throughput rates, with most students failing to complete their studies within the minimum regulatory time. Literature has begun to investigate the contribution of well-being, including mental health, with depression among students being one of the most common mental disorders explored. However, locally relevant research exploring associations between depression and academic performance has been limited. This research hypothesizes that the presence of depression symptoms, when controlling for key socio-demographic factors, has an adverse impact on student academic outcomes and contributes to the delay in the academic progression of students. METHODS: The study used a cross-sectional design. Data were collected in 2019 from first-time, first-year undergraduate students using a self-administered online questionnaire. In total, 1,642 students completed the survey. The Patient Health Questionnaire-9 (PHQ-9) was used to screen for depression symptoms. Data on students' academic performance were obtained from institutional records. Bivariate and multivariate regression analyses were used to examine associations between depression symptoms and academic performance. RESULTS: Most participants (76%) successfully progressed (meeting the requirements to proceed to the second year of university study). Of the participants, 10% displayed symptoms of severe depression. The likelihood of progression delay (not meeting the academic requirements to proceed to the second year of university study) increased with the severity of depression symptoms. Moderate depression symptoms nearly doubled the adjusted odds of progression delay (aOR = 1.98, 95% CI: 1.30-3.00, p = 0.001). The likelihood of progression delay was nearly tripled by moderate severe depression symptoms (aOR = 2.70, 95% CI:1.70-4.36, p < 0.001) and severe depression symptoms (aOR = 2.59, 95% CI:1.54-4.36, p < 0.001). The model controlled for field of study, financial aid support as well as sex and race. CONCLUSION: Higher levels of depression symptoms among first-year university students are associated with a greater likelihood of progression delay and may contribute to the low throughput rates currently seen in South African universities. It is important for students, universities and government departments to recognize student mental wellness needs and how these can be met.


Assuntos
Desempenho Acadêmico , Depressão , Humanos , Universidades , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , África do Sul/epidemiologia , Estudantes/psicologia , Inquéritos e Questionários
4.
J Frailty Sarcopenia Falls ; 7(3): 175-182, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36119552

RESUMO

Studies have shown that musculoskeletal pain is one of the most prevalent health conditions that affects many individuals worldwide. In older adults, persistent pain is a widely prevalent and a disabling condition of multiple contributing factors: physical, mental, and social. Consequently, their quality of life is hampered. We aimed to analyze the effectiveness of a multimodal circuit exercise program on chronic musculoskeletal pain and disabling in older adults. This is a randomized parallel study (two arms) with blinded outcome assessments. The participants' recruitment will be done by a non-probabilistic sampling resulting from invitations to Basic Health Units (BHU). The sample size estimation indicated 164 participants. Participants will be allocated, by means of a randomization process, to one of two groups (82 for each group): Experimental Group (multimodal circuit exercise) or Control Group (cycle of multidisciplinary lectures on pain and stretching exercise). All analyses will be processed using the RStudio software, with significance when a p-value of 2 tails is less than 5% (p<0.05). Statistical analysis will follow the intention to treat. Trial registration: ClinicalTrials.gov NCT04719130, January 20, 2021.

5.
Pharmaceuticals (Basel) ; 15(2)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35215229

RESUMO

Radiolabeled peptides with high specificity for overexpressed receptors in tumor cells hold great promise for diagnostic and therapeutic applications. In this work, we aimed at comparing the radiolabeling efficiency and biological properties of two different RGD analogs: GRGDYV and GRGDHV, labeled with iodine-131 (131I) and technetium-99m-tricarbonyl complex [99mTc][Tc(CO)3]+. Additionally, we evaluated their interaction with the αvß3 integrin molecule, overexpressed in a wide variety of tumors, including glioblastoma. Both peptides were chemically synthesized, purified and radiolabeled with 131I and [99mTc][Tc(CO)3]+ using the chloramine-T and tricarbonyl methodologies, respectively. The stability, binding to serum proteins and partition coefficient were evaluated for both radioconjugates. In addition, the binding and internalization of radiopeptides to rat C6 glioblastoma cells and rat brain homogenates from normal animals and a glioblastoma-induced model were assessed. Finally, ex vivo biodistribution studies were carried out. Radiochemical yields between 95-98% were reached for both peptides under optimized radiolabeling conditions. Both peptides were stable for up to 24 h in saline solution and in human serum. In addition, the radiopeptides have hydrophilic characteristics and a percentage of binding to serum proteins around 35% and 50% for the [131I]I-GRGDYV and [99mTc]Tc(CO)3-GRGDHV fragments, respectively. Radiopeptides showed the capacity of binding and internalization both in cell culture (C6) and rat brain homogenates. Biodistribution studies corroborated the results obtained with brain homogenates and confirmed the different binding characteristics due to the exchange of radionuclides and the presence of the tricarbonyl complex. Thereby, the results showed that both radiopeptides might be considered for future clinical applications.

6.
PLoS One ; 16(12): e0260236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34898624

RESUMO

Reading is a complex cognitive process that involves primary oculomotor function and high-level activities like attention focus and language processing. When we read, our eyes move by primary physiological functions while responding to language-processing demands. In fact, the eyes perform discontinuous twofold movements, namely, successive long jumps (saccades) interposed by small steps (fixations) in which the gaze "scans" confined locations. It is only through the fixations that information is effectively captured for brain processing. Since individuals can express similar as well as entirely different opinions about a given text, it is therefore expected that the form, content and style of a text could induce different eye-movement patterns among people. A question that naturally arises is whether these individuals' behaviours are correlated, so that eye-tracking while reading can be used as a proxy for text subjective properties. Here we perform a set of eye-tracking experiments with a group of individuals reading different types of texts, including children stories, random word generated texts and excerpts from literature work. In parallel, an extensive Internet survey was conducted for categorizing these texts in terms of their complexity and coherence, considering a large number of individuals selected according to different ages, gender and levels of education. The computational analysis of the fixation maps obtained from the gaze trajectories of the subjects for a given text reveals that the average "magnetization" of the fixation configurations correlates strongly with their complexity observed in the survey. Moreover, we perform a thermodynamic analysis using the Maximum-Entropy Model and find that coherent texts were closer to their corresponding "critical points" than non-coherent ones, as computed from the Pairwise Maximum-Entropy method, suggesting that different texts may induce distinct cohesive reading activities.


Assuntos
Tecnologia de Rastreamento Ocular , Adolescente , Adulto , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Modelos Teóricos , Leitura , Adulto Jovem
7.
Schweiz Arch Tierheilkd ; 164(11): 753-766, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-34758951

RESUMO

INTRODUCTION: Matrices that can be collected non-invasively for quantification of a stress response in sheep have received little attention in the veterinary literature. This study examines the suitability of blood, tears and saliva for determining a stress response in sheep undergoing sham foot trimming on a tilt table. The cortisol concentration of blood, tears and saliva and the concentration of cortisol metabolites in faeces were measured in 13 healthy Meat Merino ewes once a day for six days. Sham foot trimming on a tilt table was used as the stressor and was done during a one-hour period on day 4; cortisol concentrations of blood and tears were measured at 0, 10, 20, 30, 40 and 60 minutes. Cortisol concentrations of blood (maximum at 30 minutes) and tears (maximum at 40 minutes) increased during the procedure and then decreased. There were significant correlations between cortisol concentrations of blood and tears (p = 0,04) during sham foot trimming (area under the curve, 0 to 60 minutes). Over the entire 6-day study period, significant correlations were seen between the cortisol concentrations of blood and tears (r = 0,55; p.


INTRODUCTION: Les marqueurs qui peuvent être collectés de manière non invasive pour quantifier une réponse au stress chez le mouton ont fait l'objet de peu d'attention dans la littérature vétérinaire. Cette étude examine la pertinence du sang, des larmes et de la salive pour déterminer une réponse au stress chez des moutons subissant un parage fictif des pieds sur une table basculante. La concentration de cortisol dans le sang, les larmes et la salive ainsi que la concentration de métabolites de cortisol dans les fèces ont été mesurées chez 13 brebis Meat Merino saines une fois par jour pendant six jours. Le parage fictif des pieds sur une table inclinable a été utilisé comme facteur de stress et a été effectué pendant une période d'une heure le jour 4; les concentrations de cortisol dans le sang et les larmes ont été mesurées à 0, 10, 20, 30, 40 et 60 minutes. Les concentrations de cortisol dans le sang (maximum à 30 minutes) et les larmes (maximum à 40 minutes) ont augmenté au cours de la procédure puis ont diminué. Il y avait des corrélations significatives entre les concentrations de cortisol dans le sang et les larmes (p = 0,04) lors du parage fictif des onglons (aire sous la courbe, 0 à 60 minutes). Sur l'ensemble de la période d'étude de 6 jours, des corrélations significatives ont été observées entre les concentrations de cortisol dans le sang et les larmes (r = 0,55 ; p < 0,001), le sang et la salive (r = 0,53 ; p < 0,001) et les larmes et la salive (r = 0,78 ; p < 0,001). La concentration fécale de métabolites de cortisol était significativement augmentée au jour 5 (p 0,05), mais la concentration de cortisol des autres supports n'a pas changé de manière significative au cours de la période d'étude de 6 jours. Le parage fictif des pieds sur une table basculante a été considéré comme un facteur de stress aigu chez les moutons en raison de l'augmentation des concentrations de cortisol dans le sang, des larmes et de l'augmentation des concentrations de métabolites de cortisol dans les selles. La concentration de cortisol dans les larmes était similaire à celle du sang et, par conséquent, la collecte de larmes représente une alternative viable et non invasive au sang pour les tests de cortisol. Le délai des pics entre la concentration maximale de cortisol dans les larmes et le sang doit être pris en compte lors de l'interprétation des résultats.


Assuntos
Hidrocortisona , Saliva , Animais , Fezes , Feminino , Ovinos
8.
J Aging Phys Act ; 29(6): 959-967, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33863854

RESUMO

The aim of the present study is to compare the effects of 12 weeks of resistance training with machines and elastic tubes on functional capacity and muscular strength in older women aged 60 years or over. The participants were randomized into two groups: a machine group (n = 23) and an elastic group (n = 20). They performed 12 weeks of progressive resistance training, twice a week, with similar exercises. Outcomes were assessed at three time points: baseline, postintervention, and 8 weeks after the end of the training. A significant intragroup effect was demonstrated for both groups at postintervention on functional tests and muscle strength. For the functional reach test and elbow flexion strength (180°/s), only the machine group demonstrated significant intragroup differences. No differences were observed between groups for any outcome. At the 8-week follow-up, functional capacity outcome values were maintained. The muscle strength outcome values decreased to baseline scores, without differences between groups.


Assuntos
Treinamento de Força , Idoso , Exercício Físico , Terapia por Exercício , Feminino , Humanos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia
9.
Eur J Pharmacol ; 897: 173929, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33561444

RESUMO

Acute lung injury (ALI) remains to cause a high rate of mortality in critically ill patients. It is known that inflammation is a key factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI, which makes it a relevant approach to the treatment of ALI. In this study, we evaluated the potential of nasally instilled p-coumaric acid to prevent LPS-induced ALI in mice, by evaluating its effects on cellular and molecular targets involved in inflammatory response via in vitro and in silico approaches. Our results demonstrated that p-coumaric acid reduced both neutrophil accumulation and pro-inflammatory cytokine abundance, and simultaneously increased IL-10 production at the site of inflammation, potentially contributing to protection against LPS-induced ALI in mice. In the in vitro experiments, we observed inhibitory effects of p-coumaric acid against IL-6 and IL-8 production in stimulated A549 cells, as well as reactive oxygen species generation by neutrophils. In addition, p-coumaric acid treatment decreased neutrophil adhesion on the TNF-α-stimulated endothelial cells. According to the in silico predictions, p-coumaric acid reached stable interactions with both the ATP-binding site of IKKß as well as the regions within LFA-1, critical for interaction with ICAM-1, thereby suppressing the production of proinflammatory mediators and hindering the neutrophil infiltration, respectively. Collectively, these findings indicate that p-coumaric acid is a promising anti-inflammatory agent that can be used for developing a pharmaceutical drug for the treatment of ALI and other inflammatory disorders.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Anti-Inflamatórios/administração & dosagem , Ácidos Cumáricos/administração & dosagem , Pulmão/efeitos dos fármacos , Células A549 , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Administração Intranasal , Animais , Anti-Inflamatórios/metabolismo , Sítios de Ligação , Técnicas de Cocultura , Simulação por Computador , Ácidos Cumáricos/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Simulação de Acoplamento Molecular , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo
10.
J Hazard Mater ; 413: 125273, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33581669

RESUMO

Welding fume particles are hazardous. Their toxicity likely depends on their composition and reactivity. This study aimed at exploring the role of sodium or other fluorides (NaF), which are intentionally added to flux-cored wire electrodes for stainless steel welding, on the solubility (in phosphate buffered saline) and toxicity of the generated welding fume particles. A multi-analytical particle characterization approach along with in-vitro cell assays was undertaken. The release of Cr(VI) and Mn from the particles was tested as a function of fluoride solution concentration. The welding fume particles containing NaF released significantly higher amounts of Cr(VI) compared with solid wire reference fumes, which was associated with increased cytotoxicity and genotoxicity in-vitro. No crystalline Na or potassium (K) containing chromates were observed. Cr(VI) was incorporated in an amorphous mixed oxide. Solution-added fluorides did not increase the solubility of Cr(VI), but contributed to a reduced Mn release from both solid and flux-cored wire fume particles and the reduction of Cr(VI) release from solid wire fume particles. Chemical speciation modeling suggested that metal fluoride complexes were not formed. The presence of NaF in the welding electrodes did not have any direct, but possibly an indirect, role in the Cr(VI) solubility of welding fumes.


Assuntos
Poluentes Ocupacionais do Ar , Nanopartículas , Soldagem , Poluentes Ocupacionais do Ar/análise , Fluoretos , Nanopartículas/toxicidade , Solubilidade , Aço Inoxidável
11.
Biotechnol Prog ; 37(4): e3134, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33591633

RESUMO

The manner in which added non-catalytic proteins during enzymatic hydrolysis of lignocellulosic substrates enhances hydrolysis mechanisms is not completely understood. Prior research has indicated that a reduction in the non-specific adsorption of enzymes on lignin, and deactivation of enzymes exposed to air-liquid interface provide rationale. This work investigated root causes including effects of the air-liquid interface on non-catalytic proteins, and effects of lignin on endoglucanase. Three different experimental designs and three variables (air-liquid interfacial area, the types of lignin (acid or enzymatic lignin), and the presence of non-enzymatic protein (bovine serum albumin [BSA] or soy proteins ) were used. The results showed that acid isolated lignin adsorbed almost all endoglucanase activity initially present in supernatant, independent of air interface conditions (25 or 250 ml flasks) with the presence of BSA preventing this effect. Endoglucanase lost 30%-50% of its activity due to an air-liquid interface in the presence of lignin while addition of non-enzymatic protein helped to preserve this enzyme's activity. Langmuir and Freundlich models applied to experimental data indicated that the adsorption increases with increasing temperature for both endoglucanase and BSA. Adsorption of the enzyme and protein were endothermic with an increase in entropy. These results, combined, show that hydrophobicity plays a strong role in the adsorption of both endoglucanase and BSA on lignin.


Assuntos
Celulase , Lignina , Adsorção , Celulase/metabolismo , Hidrólise , Lignina/metabolismo , Soroalbumina Bovina
12.
Plant J ; 105(1): 136-150, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33111398

RESUMO

Grass cell walls have hydroxycinnamic acids attached to arabinosyl residues of arabinoxylan (AX), and certain BAHD acyltransferases are involved in their addition. In this study, we characterized one of these BAHD genes in the cell wall of the model grass Setaria viridis. RNAi silenced lines of S. viridis (SvBAHD05) presented a decrease of up to 42% of ester-linked p-coumarate (pCA) and 50% of pCA-arabinofuranosyl, across three generations. Biomass from SvBAHD05 silenced plants exhibited up to 32% increase in biomass saccharification after acid pre-treatment, with no change in total lignin. Molecular dynamics simulations suggested that SvBAHD05 is a p-coumaroyl coenzyme A transferase (PAT) mainly involved in the addition of pCA to the arabinofuranosyl residues of AX in Setaria. Thus, our results provide evidence of p-coumaroylation of AX promoted by SvBAHD05 acyltransferase in the cell wall of the model grass S. viridis. Furthermore, SvBAHD05 is a promising biotechnological target to engineer crops for improved biomass digestibility for biofuels, biorefineries and animal feeding.


Assuntos
Aciltransferases/metabolismo , Ácidos Cumáricos/metabolismo , Setaria (Planta)/metabolismo , Xilanos/metabolismo , Biomassa , Parede Celular/metabolismo , Genes de Plantas , Redes e Vias Metabólicas , Polissacarídeos/metabolismo , Setaria (Planta)/enzimologia , Setaria (Planta)/genética
13.
Rev. colomb. cienc. pecu ; 33(4): 264-272, Oct.-Dec. 2020. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1376897

RESUMO

Abstract Background: Tropical grasses, such as elephant grass, have high moisture content during its ideal phenological state for silage. High moisture content hinders proper preservation and reduces the nutritive value of silage due to secondary fermentation and production of effluents. Adding feed materials with high dry matter content, such as murumuru (Astrocaryum murumuru) meal, is a potential alternative to improve silage yield. Objective: To determine the effects of including murumuru meal (0, 7, 14, 21, and 28%) on the fermentative characteristics, microbiological activity, aerobic stability, and chemical composition of elephant grass silages. Methods: A completely randomized design with five treatments and five replicates was used. Elephant grass was collected at 60 d of age, minced, and homogenized with murumuru meal. The mass was placed in experimental 15-L silos. The silos were collected and analyzed 45 d later. Results: Effluent production decreased (p<0.05) as the proportions of murumuru meal in silage increased. A quadratic effect (p<0.05) was observed on dry matter recovery. An increase (p<0.05) was observed in dry matter content, a decrease (p<0.05) in the neutral detergent fiber content, and an increase (p<0.05) in the non-fibrous carbohydrate content with the inclusion of murumuru meal. Conclusions: Addition of murumuru meal improves chemical composition and does not affect the fermentative characteristics of elephant grass silage, while it reduces effluent losses. Nevertheless, the inclusion of murumuru meal in the elephant grass silage decreased the time of aerobic stability.


Resumen Antecedentes: los pastos tropicales, tales como el pasto elefante, tienen alto contenido de humedad cuando están en su estado fenológico ideal para ensilar. Esto dificulta su adecuada preservación en el silo, reduciendo el valor nutritivo del ensilaje debido a fermentaciones secundarias y generación de efluentes. Una posible solución sería incluir materiales con alto contenido de materia seca, tales como la torta de murumuru (Astrocaryum murumuru). Objetivo: determinar el efecto de la inclusión de torta de murumuru (0; 7; 14; 21 y 28%) sobre las características fermentativas, microbiológicas, estabilidad aeróbica y composición química de los ensilajes de pasto elefante. Métodos: se utilizó un diseño completamente al azar, con cinco tratamientos y cinco repeticiones. El pasto elefante fue colectado a los 60 días de edad, luego picado y homogeneizado con la torta de murumuru. La masa fue colocada en silos experimentales con capacidad de 15 L. Luego de 45 días de ensilado, los silos fueron abiertos y las muestras fueron colectadas para su posterior análisis. Resultados: hubo reducción (p<0,05) en la producción de efluentes a medida que se incrementó la proporción de torta de murumuru en el ensilado. Se observó un efecto cuadrático (p<0,05) en la recuperación de materia seca. Hubo aumento (p<0,05) en los contenidos de materia seca con la adición de torta de murumuru. Se observó disminución (p<0,05) en el contenido de fibra detergente neutra y aumento (p<0,05) de carbohidratos no fibrosos. Conclusión: La adición de torta de murumuru mejora la composición química, reduce las perdidas por efluentes y no afecta las características fermentativas de ensilado de pasto elefante. Sin embargo, la inclusión de la torta de murumuru en el ensilado de pasto elefante disminuye el tiempo en estabilidad aeróbica.


Resumo Antecedentes: capins tropicais, como por exemplo o capim-elefante apresentam alto teor de umidade quando possuem produtividade compatível e estão no estádio fenológico adequado para ensilagem. Isso dificulta a adequada preservação no silo, ocasionando a redução do valor nutritivo da silagem devido a fermentações secundárias e a produção de efluentes. Uma possível solução seria o uso de aditivos com alto teor de matéria seca, como bolo de murumuru (Astrocaryum murumuru). Objetivo: determinar o efeito da inclusão da torta de murumuru (0; 7; 14; 21 e 28%) na ensilagem de capim-elefante sobre as características fermentativas, microbiológicas, estabilidade aeróbia e a composição química das silagens. Métodos: utilizou- se um delineamento inteiramente casualizado, com cinco tratamentos e cinco repetições. O capim-elefante foi colhido aos 60 dias de idade, o mesmo foi picado e homogeneizado à torta de murumuru. A massa foi ensilada em silos experimentais com capacidade de 15 L. Após 45 dias de ensilagem, os silos foram abertos e amostras foram coletadas para posteriores análises laboratoriais. Resultados: houve redução (p<0,05) na produção de efluentes à medida que se elevaram as proporções da torta de murumuru na ensilagem. Observou-se efeito quadrático (p<0,05) na recuperação de matéria seca. Houve aumento (p<0,05) nos teores de matéria seca com a adição da torta murumuru. Observou-se diminuição (p<0,05) nos teores de fibra em detergente neutro e aumento (p<0,05) nos teores de carboidratos não fibrosos. Conclusão: torta de murumuru como aditivo melhora a composição química, reduz perdas principalmente por efluente e não afeta as características fermentativas de silagens de capim- elefante. Entretanto, a inclusão da torta de murumuru na ensilagem de capim-elefante diminui o tempo em estabilidade aeróbia.

14.
BMC Microbiol ; 20(1): 330, 2020 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129264

RESUMO

BACKGROUND: Comparisons of traditional hunter-gatherers and pre-agricultural communities in Africa with urban and suburban Western North American and European cohorts have clearly shown that diet, lifestyle and environment are associated with gut microbiome composition. Yet, little is known about the gut microbiome composition of most communities in the very diverse African continent. South Africa comprises a richly diverse ethnolinguistic population that is experiencing an ongoing epidemiological transition and concurrent spike in the prevalence of obesity, largely attributed to a shift towards more Westernized diets and increasingly inactive lifestyle practices. To characterize the microbiome of African adults living in more mainstream lifestyle settings and investigate associations between the microbiome and obesity, we conducted a pilot study, designed collaboratively with community leaders, in two South African cohorts representative of urban and transitioning rural populations. As the rate of overweight and obesity is particularly high in women, we collected single time-point stool samples from 170 HIV-negative women (51 at Soweto; 119 at Bushbuckridge), performed 16S rRNA gene sequencing on these samples and compared the data to concurrently collected anthropometric data. RESULTS: We found the overall gut microbiome of our cohorts to be reflective of their ongoing epidemiological transition. Specifically, we find that geographical location was more important for sample clustering than lean/obese status and observed a relatively higher abundance of the Melainabacteria, Vampirovibrio, a predatory bacterium, in Bushbuckridge. Also, Prevotella, despite its generally high prevalence in the cohorts, showed an association with obesity. In comparisons with benchmarked datasets representative of non-Western populations, relatively higher abundance values were observed in our dataset for Barnesiella (log2fold change (FC) = 4.5), Alistipes (log2FC = 3.9), Bacteroides (log2FC = 4.2), Parabacteroides (log2FC = 3.1) and Treponema (log2FC = 1.6), with the exception of Prevotella (log2FC = - 4.7). CONCLUSIONS: Altogether, this work identifies putative microbial features associated with host health in a historically understudied community undergoing an epidemiological transition. Furthermore, we note the crucial role of community engagement to the success of a study in an African setting, the importance of more population-specific studies to inform targeted interventions as well as present a basic foundation for future research.


Assuntos
Microbioma Gastrointestinal/genética , Estilo de Vida/etnologia , Microbiota/genética , Adulto , Idoso , Bactérias/genética , Biomarcadores , Estudos de Coortes , Dieta , Fezes/microbiologia , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/microbiologia , Projetos Piloto , RNA Ribossômico 16S/genética , População Rural , África do Sul/etnologia
15.
PLoS One ; 15(10): e0240789, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091017

RESUMO

In a recent study, using an in vitro model to study intravaginal nanoparticle exposure during yeast infections, we demonstrated that C. albicans exposure suppressed apoptotic gene expression and induced oxidative stress and pyroptosis in vaginal epithelial cells. The mucous-penetrating drug delivery nanoparticles made from poly-(D, L-lactic-co-glycolic acid)-(polyethylene glycol) induced cytotoxicity by activating apoptosis, endoplasmic reticulum (ER) stress, oxidative stress, and DNA damage repair responses alone and, in some cases with C. albicans. In the current study we evaluated the effects of fluorescently-labelled nanoparticles in CBA/J mice challenged intravaginally for two hours followed by intravaginal challenge with C. albicans for 18 hours. Nanoparticle treatment increased systemic translocation of C. albicans threefold in the heart. C. albicans also increased systemic distribution of the nanoparticles fivefold in the heart. Flow cytometric assays showed co-localization of the nanoparticles with epithelial cells, macrophages and dendritic cells. Nanoparticle-treated, C. albicans-infected mice exhibited induction of autophagy, ER stress, apoptosis, and inflammatory serum cytokines. C. albicans infection was associated with pyroptosis and suppressed expression of ER stress and apoptosis-related genes. Induction of apoptosis during nanoparticle treatment and in nanoparticle-treated-C. albicans infected mice was observed as DNA damage responses, mitochondrial depolarization and (Poly [ADP-Ribose] Polymerase) cleavage. C. albicans infection was associated with increased mRNA expression of anti-apoptotic genes. Both C. albicans infection and nanoparticle treatment showed enhanced chemoattraction of dendritic cells and polymorphonuclear cells to factors in vaginal washings in a chemotaxis assay. This study shows that both intravaginal treatment of mice with the nanoparticles and infection with C. albicans induce cytotoxic and inflammatory responses. C. albicans also suppressed cell apoptosis. These results clarify our understanding of how nanoparticles modulate host cellular responses during C. albicans infection and will be applicable for future research and development of intravaginal nanomedicines.


Assuntos
Candida albicans/fisiologia , Candidíase/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Inflamação/genética , Nanopartículas/química , Polietilenoglicóis/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Vagina/microbiologia , Animais , Apoptose , Candidíase/genética , Candidíase/microbiologia , Linhagem Celular , Quimiotaxia , Citocinas/metabolismo , Células Dendríticas/patologia , Modelos Animais de Doenças , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos CBA , Neutrófilos/patologia , Especificidade de Órgãos , Estresse Fisiológico , Vagina/patologia , Leveduras
16.
Eur J Radiol ; 132: 109297, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33035918

RESUMO

PURPOSE: Our study sought to evaluate validity of forensic postmortem CT in establishing cause of death (COD) in suspected unnatural adult death based on the reference standard of autopsy. METHODS: In our prospective, single-center study, 64 of 94 consecutive corpses (70.7 % male, mean age: 47.4 years) who underwent CT and autopsy between November 2013 and April 2019 were included in the analysis. Primary objective was agreement between CT and autopsy on primary COD using kappa statistics. Secondary objectives were competing COD and specific pathological findings. RESULTS: Agreement on primary COD between forensic CT and autopsy without or in consideration of toxicological and histological findings was strong (85.9 % [55 of 64 corpses]; κ = 0.83 [95 %CI: 0.74 to 0.93] and 95.3 % [61 of 64 corpses]; κ = 0.94 [95 %CI: 0.84-1.04], respectively, McNemar p = 0.03). Sensitivity and specificity of CT in identification of acute heart failure, intracranial bleeding, burns and heat shocks, gunshot wounds, polytrauma, cranio-cerebral trauma, and strangulation or hanging was 100 %, each. Acute respiratory failure was detected with a sensitivity and specificity of 100 % and 96.8 %, cuts and stab wounds with 95.2 % and 100 %, and intoxication, pneumonia, or gastrointestinal bleeding with 60.0 % and 100 %, respectively. Agreement on competing COD was moderate (51.6 %, [33 of 64 corpses]; κ = 0.47 [95 %CI: 0.40 to 0.53], p < 0.001). CONCLUSIONS: Forensic postmortem CT, complemented by external, toxicological, and histological examination was sufficiently valid to assess primary COD in the majority of suspected unnatural deaths with few restrictions.


Assuntos
Ferimentos por Arma de Fogo , Adulto , Autopsia , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia Computadorizada por Raios X
17.
Science ; 369(6511): 1630-1633, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32973029

RESUMO

Addressing the ultrafast coherent evolution of electronic wave functions has long been a goal of nonlinear x-ray physics. A first step toward this goal is the investigation of stimulated x-ray Raman scattering (SXRS) using intense pulses from an x-ray free-electron laser. Earlier SXRS experiments relied on signal amplification during pulse propagation through dense resonant media. By contrast, our method reveals the fundamental process in which photons from the primary radiation source directly interact with a single atom. We introduce an experimental protocol in which scattered neutral atoms rather than scattered photons are detected. We present SXRS measurements at the neon K edge and a quantitative theoretical analysis. The method should become a powerful tool in the exploration of nonlinear x-ray physics.

18.
Nucl Med Biol ; 88-89: 14-23, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663774

RESUMO

Radiolabeled peptides with high specificity to receptors expressed on tumor cells hold a great promise as diagnostic and therapeutic tracers. The main objective of this study was to evaluate the radiochemical and biological properties of two [131I]I-peptides, as well as their interaction with the epidermal growth factor receptor (EGFR), overexpressed in a wide variety of tumors, including glioblastoma. The EEEEYFELV peptide and its analogue DEDEYFELV, both designed to interact with EGFR, were chemically synthesized, purified and radiolabeled with iodine-131 ([131I]NaI). The radioiodination was evaluated and optimized using the chloramine-T methodology. The stability, serum proteins binding and partition coefficient were assessed for both radioconjugates. Moreover, the binding and internalization of synthesized radiopeptides with rat glioblastoma cells (C6) and with rat brain homogenates from a glioblastoma induced model were evaluated and ex vivo biodistribution studies were performed. Under optimized radiolabeling conditions, the peptides showed an average radiochemical yield of 90-95%. The stability studies showed that both peptides were stable up to 24 h in reaction medium, saline, and human serum. Furthermore, [131I]I-peptides have hydrophilic features and showed binding percentage to serum proteins of around 50%, which is highly compatible with clinical applications. Moreover, the radiopeptides presented capacity for binding and internalization in both tumor cells (C6) and rat brain tissues after tumor induction. Biodistribution studies corroborated the cell culture studies and confirmed the different binding characteristics derived from a simple change of two amino acids (Glu ➔ Asp1,3) in their sequences. The results obtained are consistent enough to motivate further studies. Thereby, these radiolabeled peptides might be useful for diagnostic applications.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Radioisótopos do Iodo/farmacocinética , Fragmentos de Peptídeos/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Animais , Apoptose , Neoplasias Encefálicas/metabolismo , Proliferação de Células , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Food Chem ; 330: 127187, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531636

RESUMO

The objective of this study was to evaluate the chemical composition and fatty acid profile of broilers fed diets containing glycerol monolaurate (GML) in place of antimicrobials. Groups: T0 group used as control; T100, T200, and T300 groups received diets supplemented with 100, 200, and 300 mg/kg of GML, respectively. The feed mixture used in the poultry feed during the four phases of the production cycle (days 1 to 7; 8 to 21; 22 to 35; and 36 to 42 of birds age) showed similar levels of protein, lipid and ash, as well as fatty acid profiles. Samples of frozen breasts from chickens slaughtered at 42 days of age were used for chemical gross composition and fatty acid analysis. We observed lower lipid levels in the meat of broilers in the T200 and T300 groups than in the T0 group. Lower lipid peroxidation occurred in the meat of animals that consumed GML in respect to control. Total saturated fatty acid percentage was lower, while total polyunsaturated fatty acid percentage was higher in the meat of broilers fed GML than in the control group. We conclude that the increase in GML concentrations alters the lipid profile of broiler meat.


Assuntos
Ácidos Graxos/química , Lauratos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Carne/análise , Monoglicerídeos/farmacologia , Ração Animal , Animais , Galinhas , Ácidos Graxos/análise
20.
J Exerc Sci Fit ; 18(3): 148-154, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32514278

RESUMO

BACKGROUND/OBJECTIVE: Roller massage has become a popular intervention in sports settings in order to treat muscle soreness and stiffness, as well as improving post-exercise recovery, although there is limited evidence for these assumptions. Therefore, the purpose of this study was to evaluate the effects of a single session of roller massage, applied with a controlled force after an exercise-induced muscle damage protocol, on muscle recovery. METHODS: A randomized controlled study was performed using a repeated-measures design. Thirty-six young men completed four sets of six eccentric actions of elbow flexors at 90°/s with a 90s rest interval between sets. Participants were randomly assigned into one of three groups: 1) Roller massage (n = 12), 2) Sham (n = 12), and 3) Control (n = 12). Maximal isometric voluntary contraction (MIVC), delayed-onset muscle soreness (DOMS), range of motion (ROM), and muscle thickness were measured at baseline, and at 24, 48, and 72 h post exercise. RESULTS: There was no significant group by time interaction for MIVC (p = 0.090) and ROM (p = 0.416). Also, although there was a significant group by time interaction for muscle thickness (p = 0.028), post hoc test did not find significant difference between groups (p > 0.05). DOMS was recovered at 72 h for roller massage (p < 0.001) and control (p < 0.001) groups, while the Sham group did not recover from DOMS across 72 h (p < 0.001). There was also no significant difference between groups in DOMS at any time (p > 0.05). CONCLUSIONS: A single session of roller massage applied on elbow flexors had no effect on recovery of MIVC, muscle swelling, ROM and DOMS.

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