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OBJECTIVE: Polyphenols are organic compounds with diverse biological activities such as anti-inflammatory and antioxidant effects, making them important candidates for the development of anti-aging drugs. In this systematic review, we aimed to answer the question: can plant-derived polyphenols have an immunomodulatory effect in experimental models of aging? METHODS: We systematically searched Web of Science, MEDLINE/Pubmed, and Embase to select articles using the following combinations of terms and synonyms: polyphenols, phenols, senescence, aging, and immune. The selected articles were evaluated for reporting quality and risk-of-bias according to standard guidelines. RESULTS: The most used polyphenol was resveratrol, followed by curcumin, salidroside, and gallic acid. These molecules demonstrated an ability to restore immune function both in vitro and in vivo. The mechanism of action was not completely elucidated in these studies, but inhibition of NF-kB signaling, and antioxidant properties seemed to account for the anti-aging effects. All articles included in the review had good quality of reporting but failed to describe an adequate sample size, criteria for inclusion/exclusion, randomization, and blinding. CONCLUSION: We conclude that polyphenols are promising immunomodulatory substances for use in anti-aging therapies. However, more research with standardized analysis is needed to understand the role of these molecules in the prevention or reduction of damage associated with the aging process, as well as to determine the safety profile and consequences of systemic action.
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Envelhecimento , Sistema Imunitário , Polifenóis , Animais , Humanos , Envelhecimento/imunologia , Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Sistema Imunitário/efeitos dos fármacos , Agentes de Imunomodulação/farmacologia , Polifenóis/farmacologiaRESUMO
Bioplastics are a sustainable and environmental-friendly alternative to the conventional petroleum-based plastics, namely due to their source (biobased) and due to their biodegradability or both. Polyhydroxyalkanoates (PHA) stand out among the bioplastics group by being intracellular biobased, biodegradable and biocompatible polymers. PHA production has been highly investigated during the last decades. However, to date, PHA production has been monitored through offline and time-consuming tools, involving hazardous solvents, not allowing a timely control of the bioprocesses, which often results in a loss of process productivity and hinders its implementation at full scale. Therefore, two-dimensional (2D) fluorescence spectroscopy was assessed for monitoring the PHA content at real-time, as it is a non-destructive, solvent-free and non-invasive technique. The complex information of the biological broth was captured within fluorescence excitation-emission matrices (EEMs), which were deconvoluted through projection to latent structures (PLS) modelling to estimate PHA production by an enriched PHA microbial culture, using fermented brewer's spent grain as feedstock. A good correlation for PHA prediction was achieved, with an average error of ca. 4.0% gPHA/gTS for new predictions. This work demonstrates the great potential of using 2D fluorescence spectroscopy to assess the intracellular PHA content without requiring staining agents. Moreover, it unlocks the possibility of an online and real-time monitoring of the biopolymer production processes, which will contribute towards the improvement of the PHA process productivity and, consequently, its implementation at full scale.
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In the context of a circular bio-based economy, more public attention has been paid to the environmental sustainability of biodegradable bio-based plastics, particularly plastics produced using emerging biotechnologies, e.g. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV. However, this has not been thoroughly investigated in the literature. Therefore, this study aimed to address three aspects regarding the environmental impact of PHBV-based plastic: (i) the potential environmental benefits of scaling up pellet production from pilot to industrial scale and the environmental hotspots at each scale, (ii) the most favourable end-of-life (EOL) scenario for PHBV, and (iii) the environmental performance of PHBV compared to benchmark materials considering both the pellet production and EOL stages. Life cycle assessment (LCA) was implemented using Cumulative Exergy Extraction from the Natural Environment (CEENE) and Environmental Footprint (EF) methods. The results show that, firstly, when upscaling the PHBV pellet production from pilot to industrial scale, a significant environmental benefit can be achieved by reducing electricity and nutrient usage, together with the implementation of better practices such as recycling effluent for diluting feedstock. Moreover, from the circularity perspective, mechanical recycling might be the most favourable EOL scenario for short-life PHBV-based products, using the carbon neutrality approach, as the material remains recycled and hence environmental credits are achieved by substituting recyclates for virgin raw materials. Lastly, PHBV can be environmentally beneficial equal to or even to some extent greater than common bio- and fossil-based plastics produced with well-established technologies. Besides methodological choices, feedstock source and technology specifications (e.g. pure or mixed microbial cultures) were also identified as significant factors contributing to the variations in LCA of (bio)plastics; therefore, transparency in reporting these factors, along with consistency in implementing the methodologies, is crucial for conducting a meaningful comparative LCA.
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Hidroxibutiratos , Ácidos Pentanoicos , Poliésteres , Poli-Hidroxibutiratos , BiotecnologiaRESUMO
Microalgae are photosynthetic organisms that can produce biomolecules with industrial interest, including exopolysaccharides (EPS). Due to their structural and compositional diversity, microalgae EPS present interesting properties that can be considered in cosmetic and/or therapeutic areas. Seven microalgae strains from three different lineages, namely Dinophyceae (phylum Miozoa), Haptophyta, and Chlorophyta, were investigated as EPS producers. All strains were found to be EPS producers, though the highest EPS yield was obtained for Tisochrysis lutea, followed by Heterocapsa sp. (126.8 and 75.8 mg L-1, respectively). Upon assessment of the polymers' chemical composition, significant contents of unusual sugars, including fucose, rhamnose, and ribose, were found. Heterocapsa sp. EPS stood out due to its high content of fucose (40.9 mol%), a sugar known to confer biological properties to polysaccharides. The presence of sulfate groups (10.6-33.5 wt%) was also noticed in the EPS produced by all microalgae strains, thus contributing to the possibility that these EPS might have biological activities worth exploring.
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Microalgas , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Fucose , BioprospecçãoRESUMO
OBJECTIVE: To develop an equation with clinical applicability and adequate validity to predict the maximum oxygen consumption (VÌo2max) of individuals post-stroke. DESIGN: A cross-sectional study. SETTING: A university laboratory. PARTICIPANTS: Individuals post-stroke in the chronic phase (at least 6 months post-stroke). Step-1 (equation development): n=50, aged 55±12 years; Step-2 (validity investigation): n=20, aged 58±8 years (N=50 [step 1], N=20 [step 2]). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): Step-1 (equation development): multiple linear regression analysis was performed. DEPENDENT VARIABLE: VÌo2max (mL/kg/min) in the cardiopulmonary exercise test. INDEPENDENT VARIABLES: age (years), sex (1-women, 2-men), body mass index (BMI) (kg/m2), and distance (meters) in the Six-Minute Walk Test (6MWT) (6MWT-Equation) or in the Incremental Shuttle Walk Test (ISWT) (ISWT-Equation). Step-2 (validity investigation): agreement between the VÌo2max measured and predicted was evaluated with the intraclass correlation coefficient (ICC) with 95% confidence interval (CI) and the Bland-Altman method (α=5%). RESULTS: In step-1 (equation development), the 4 independent variables for each equation were retained (6MWT-Equation: R2=0.68, P<.001; ISWT-Equation: R2=0.58, P<.001). In step-2 (validity investigation), the 6MWT-Equation showed an ICC of 0.73 (95% CI=0.30, 0.89; P=.004) and a mean bias of 0.003 mL/kg/min; and the ISWT-Equation showed an imprecise ICC of 0.55 (95% CI=-0.12, 0.82; P=.045) and a mean bias of 0.971 mL/kg/min. 6MWT-Equation (VÌo2max=22.239+0.02 × distance in the 6MWT+4.039 × sex-0.157 × age-0.265 × BMI) showed adequate validity. CONCLUSIONS: An equation with clinical applicability and adequate validity in the investigated sample was developed to predict the VÌo2max of individuals post-stroke in the chronic phase (6MWT-Equation). Future studies with larger sample should investigate its external validity.
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Teste de Esforço , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Estudos Transversais , Teste de Esforço/métodos , Teste de Caminhada/métodos , Consumo de Oxigênio , Caminhada , Reprodutibilidade dos TestesRESUMO
Polyhydroxyalkanoates (PHAs) are natural polyesters which biodegrade in soils and oceans but have more than double the cost of comparable oil-based polymers. PHA downstreaming from its biomass represents 50% of its overall cost. Here, in an attempt to assist downstreaming, mastication of wet biomasses is tested as a new mechanical continuous biomass pretreatment with potential for industrial upscaling. Downstreaming conditions where both product recovery and purity are low due to the large amount of treated wet biomass (50% water) were targeted with the following process: extraction of 20 g in 100 mL solvent at 30 °C for 2 h, followed by 4.8 h digestion of 20 g in 0.3 M NaOH. Under the studied conditions, NaOH digestion was more effective than solvent extraction in recovering larger PHA amounts, but with less purity. A nearly 50% loss of PHA was seen during digestion after mastication. PHAs downstreamed by digestion with large amounts of impurities started to degrade at lower temperatures, but their melt elasticity was thermally stable at 170 °C. As such, these materials are attractive as fully PHA-compatible processing aids, reinforcing fillers or viscosity modifiers. On the other hand, wet biomass mastication before solvent extraction improves PHA purity and thermal stability as well as the melt rheology, which recovers the viscoelasticity measured with a PHA extracted from a dried biomass.
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Reatores Biológicos , Poli-Hidroxialcanoatos , Biomassa , Poli-Hidroxialcanoatos/metabolismo , Mastigação , Hidróxido de Sódio , SolventesRESUMO
BACKGROUND: Most of the current materials used in food packaging are synthetic and non-degradable, raising environmental issues derived from the accumulation of plastics in landfills/waterways. The food industry increasingly needs eco-friendly sustainable materials that meet food-packaging requirements. Bacterial nanocellulose (BNC), a biopolymer obtained by fermentation, offers very good mechanical properties and the ability to carry and deliver active substances. However, its water-vapor permeability is too high for food-packaging applications. In this work, a layered biodegradable composite based on BNC and polyhydroxyalkanoate (PHBV) was produced, attempting to improve its overall barrier properties. Polyhydroxyalkanoate is a biopolymer with high degree of hydrophobicity and biodegradability, and is also obtained by fermentation. Wet BNC membranes produced by static culture were plasticized by impregnation of solutions of either glycerol (BNCgly ) or polyethylene glycol (MW 600) (BNCPEG ). The plasticized BNC was then coated with PHBV solution dissolved in formic acid, and oven dried at 148 °C. RESULTS: Overall, PHBV coating on plasticized BNC reduced water vapor permeability significantly (from 0.990 to 0.032 g.µm.m-2 .day-1 .Pa-1 ) under 50% relative humidity. It increased the hydrophobicity (contact angle from 10-40° to 80-90°) but decreased the stiffness (from 3.1 GPa to 1.3 Gpa) of the composite. CONCLUSIONS: Overall, the mechanical and barrier properties of the layered composite obtained were considered suitable for food-packaging applications. The plasticizing (with glycerol or polyethylene glycol) of BNC significantly improved the mechanical performance and the PHBV coating reduced the water affinity (vapor and liquid state) on BNC. © 2022 Society of Chemical Industry.
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Celulose , Poli-Hidroxialcanoatos , Celulose/química , Embalagem de Alimentos , Glicerol , Biopolímeros , BactériasRESUMO
OBJECTIVE: To propose a new decision algorithm combining biomarkers measured in a tumor biopsy with clinical variables, to predict recurrence after liver transplantation (LT). BACKGROUND: Liver cancer is one of the most frequent causes of cancer-related mortality. LT is the best treatment for hepatocellular carcinoma (HCC) patients but the scarcity of organs makes patient selection a critical step. In addition, clinical criteria widely applied in patient eligibility decisions miss potentially curable patients while selecting patients that relapse after transplantation. METHODS: A literature systematic review singled out candidate biomarkers whose RNA levels were assessed by quantitative PCR in tumor tissue from 138 HCC patients submitted to LT (>5 years follow up, 32% beyond Milan criteria). The resulting 4 gene signature was combined with clinical variables to develop a decision algorithm using machine learning approaches. The method was named HepatoPredict. RESULTS: HepatoPredict identifies 99% disease-free patients (>5 year) from a retrospective cohort, including many outside clinical criteria (16%-24%), thus reducing the false negative rate. This increased sensitivity is accompanied by an increased positive predictive value (88.5%-94.4%) without any loss of long-term overall survival or recurrence rates for patients deemed eligible by HepatoPredict; those deemed ineligible display marked reduction of survival and increased recurrence in the short and long term. CONCLUSIONS: HepatoPredict outperforms conventional clinical-pathologic selection criteria (Milan, UCSF), providing superior prognostic information. Accurately identifying which patients most likely benefit from LT enables an objective stratification of waiting lists and information-based allocation of optimal versus suboptimal organs.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Seleção de Pacientes , RNA , Estudos Retrospectivos , Fatores de Risco , TranscriptomaRESUMO
BACKGROUND: The thymus is responsible for thymocyte differentiation into immunocompetent T lymphocytes. Different cell types in the thymic microenvironment actively cooperate in this process, interacting with the developing thymocytes through soluble factors, extracellular matrix (ECM) molecules, and receptors. In addition, this microenvironment can be influenced by several factors, such as semaphorin-3A (Sema3A), which is a multifunctional protein involved in cell migration. We evaluated the Sema3A effects on the cellular parameters and functional features of thymic stromal cells. METHODS: Thymic stromal cells were obtained by enzymatic digestion of the murine thymus. These cells were treated with Sema3A and evaluated as follows: cell morphology by scanning electron microscope, F-actin cytoskeleton and deposition of ECM molecules by fluorescence microscopy, and adhesion assays with freshly obtained thymocytes. RESULTS: The obtained thymic stroma was composed of 67% of thymic epithelial cells (TECs), and 90% of the TECs were positive for the Sema3A receptor neuropilin-1. These cells secreted CXCL12, IL-7 and extended thymocyte survival. Sema3A changed the morphology of thymic stromal cells and promoted F-actin reorganization. In addition, the fibronectin fibers were reoriented, and the laminin production was increased in Sema3A-treated thymic stromal cells. In the adhesion assays, there was an increase in the number of adhered thymocytes when thymic stromal cells were pretreated with Sema3A. CONCLUSION: Our data strongly suggest the active participation of Sema3A in thymic physiology, highlighting its role as an immunomodulatory molecule. This may provide important knowledge for understanding the interactions of thymic cells.
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Semaforina-3A , Timócitos , Animais , Movimento Celular , Células Epiteliais , Camundongos , Células EstromaisRESUMO
OBJECTIVES: To compare five distinct methods to score the peak of oxygen consumption (VO2peak) obtained through the cardiopulmonary exercise testing (CPET) in individuals after stroke. MATERIALS AND METHODS: The VO2peak was obtained through the CPET with five methods: method-1: the highest value of the test; method-2: the highest value of the last 30 seconds at peak exercise; method-3: the mean of the last 30 seconds at peak exercise; method-4: the mean of the last 20 seconds at peak exercise; method-5: the highest value averaged of the 3 last blocks of 10 seconds at peak exercise. The coefficient of variance (CV) and the mean differences with 95% confidence interval (CI) between the scoring methods were calculated. A post-hoc test (Tukey HSD) was performed to calculate the adjusted 95%CI. RESULTS: Fifty-nine individuals were included (54±12 years, 56±60 months after stroke). The CV of the methods 1-to-5 were, respectively: 27.91%, 25.77%, 23.38%, 23.83%, and 23.33%. There was no difference between method-1 and method-2 (95%CI: -1.10 to 4.69) and between methods 3 to 5: method-3 and method-4 (95%CI: -2.97 to 2.82); method-3 and method-5 (95%CI: -3.57 to 2.22); method-4 and method-5 (95%CI: -3.49 to 2.30). However, method-1 and -2 provided VO2peak values different from that of methods 3-to-5. CONCLUSIONS: The scoring method of obtaining the VO2peak has an influence on its magnitude. Since methods 3-to-5 showed lower CV and provided similar values, they should be used to calculate the VO2peak obtained through the CPET in individuals after stroke.
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Aptidão Cardiorrespiratória , Acidente Vascular Cerebral , Exercício Físico , Teste de Esforço , Humanos , Consumo de Oxigênio , Acidente Vascular Cerebral/diagnósticoRESUMO
In the present study, three different newly developed copolymers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 20, 40, and 60 mol % contents in 3-hydroxyvalerate (3HV) were produced by the biotechnological process of mixed microbial cultures (MMCs) using cheese whey (CW), a by-product from the dairy industry, as feedstock. The CW-derived PHBV copolyesters were first purified and then processed by solution electrospinning, yielding fibers of approximately 2 µm in cross-section in all cases. The resultant electrospun PHBV mats were, thereafter, post-processed by annealing at different temperatures, below their maximum of melting, selected according to their 3HV content in order to obtain continuous films based on coalesced fibers, so-called biopapers. The resultant PHBV films were characterized in terms of their morphology, crystallinity, and mechanical and barrier properties to assess their potential application in food packaging. The CW-derived PHBV biopapers showed high contact transparency but a slightly yellow color. The fibers of the 20 mol % 3HV copolymer were seen to contain mostly poly(3-hydroxybutyrate) (PHB) crystals, the fibers of the 40 mol % 3HV copolymer a mixture of PHB and poly(3-hydroxyvalerate) (PHV) crystals and lowest crystallinity, and the fibers of the 60 mol % 3HV sample were mostly made of PHV crystals. To understand the interfiber coalesce process undergone by the materials during annealing, the crystalline morphology was also assessed by variable-temperature both combined small-angle and wide-angle X-ray scattering synchrotron and Fourier transform infrared experiments. From these experiments and, different from previously reported biopapers with lower 3HV contents, all samples were inferred to have a surface energy reduction mechanism for interfiber coalescence during annealing, which is thought to be activated by a temperature-induced decrease in molecular order. Due to their reduced crystallinity and molecular order, the CW-derived PHBV biopapers, especially the 40 mol % 3HV sample, were found to be more ductile and tougher. In terms of barrier properties, the three copolymers performed similarly to water and limonene, but to oxygen, the 40 mol % sample showed the highest relative permeability. Overall, the materials developed, which are compatible with the Circular Bioeconomy organic recycling strategy, can have an excellent potential as barrier interlayers or coatings of application interest in food packaging.
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Queijo , Soro do Leite , Hidroxibutiratos , Ácidos Pentanoicos , PoliésteresRESUMO
BACKGROUND: MOSKI KIT® is a fun tool designed to interest children for prevention and management of malaria. This study was carried out with the objective to assess the short- and long-term impacts of this tool on the knowledge, attitudes, and practices of school children, and on the transmission of the knowledge received at the household level as well. METHOD: The study took place in elementary schools in the city centre (with relatively low endemicity) and in the Niayes area (at high risk of anopheline and malaria) in the Dakar region of Senegal. The various schools chosen for this study were divided into an intervention group and a control group. The intervention schools were also divided into two subgroups, a full package subgroup and another partial package. During this study three surveys were conducted, the first one before exposure to the MOSKI KIT®, the second one a week later and the third a year later. For the control schools only one survey was conducted and at the same time than the third for the intervention schools. Two household surveys (a week and a year after exposure) were also conducted for the intervention schools against one for the control schools. RESULTS: Before sensitization, the proportion of school children with a grade above or equal to the average was 50% for the complete package subgroup (CPS) and 53% for the partial package subgroup (PPS). A week later, these proportions were 69% and 71%, respectively for the complete and PPSs. A year later, they were 99.4% for the CPS, 98.1% for the PPS and 99.5% for the control group; The number of children who spoke to their parents about malaria was greater in intervention schools than that of control schools. They were 46.63% and 32.58%, respectively in intervention and control schools. CONCLUSION: The MOSKI KIT, has enabled an increase of the knowledge of school children about malaria in the short term and favoured its retention in the long term. However, its impact was not felt on their attitudes and practices.
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Conhecimentos, Atitudes e Prática em Saúde , Malária/prevenção & controle , Estudantes , Criança , Feminino , Humanos , Masculino , Pais , Instituições Acadêmicas , Senegal , Inquéritos e QuestionáriosRESUMO
Marine environments comprise almost three quarters of Earth's surface, representing the largest ecosystem of our planet. The vast ecological and metabolic diversity found in marine microorganisms suggest that these marine resources have a huge potential as sources of novel commercially appealing biomolecules, such as exopolysaccharides (EPS). Six Alteromonas strains from different marine environments in French Polynesia atolls were selected for EPS extraction. All the EPS were heteropolysaccharides composed of different monomers, including neutral monosaccharides (glucose, galactose, and mannose, rhamnose and fucose), and uronic acids (glucuronic acid and galacturonic acid), which accounted for up to 45.5 mol% of the EPS compositions. Non-carbohydrate substituents, such as acetyl (0.5-2.1 wt%), pyruvyl (0.2-4.9 wt%), succinyl (1-1.8 wt%), and sulfate (1.98-3.43 wt%); and few peptides (1.72-6.77 wt%) were also detected. Thermal analysis demonstrated that the EPS had a degradation temperature above 260 °C, and high char yields (32-53%). Studies on EPS functional properties revealed that they produce viscous aqueous solutions with a shear thinning behavior and could form strong gels in two distinct ways: by the addition of Fe2+, or in the presence of Mg2+, Cu2+, or Ca2+ under alkaline conditions. Thus, these EPS could be versatile materials for different applications.
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Alteromonas , Polissacarídeos Bacterianos/química , Animais , Organismos Aquáticos , Biotecnologia , PolinésiaRESUMO
The growing consumer demand for natural products led to an increasing interest in vanillin production by biotechnological routes. In this work, the biotechnological vanillin production by Amycolatopsis sp. ATCC 39116 is studied using ferulic acid as precursor, aiming to achieve maximized vanillin productivities. During biotech-vanillin production, the effects of glucose, vanillin and ferulic acid concentrations in the broth proved to be relevant for vanillin productivity. Concerning glucose, its presence in the broth during the production phase avoids vanillin conversion to vanillic acid and, consequently, increases vanillin production. To avoid the accumulation of vanillin up to a toxic concentration level, a multiple-pulse-feeding strategy is implemented, with intercalated vanillin removal from the broth and biomass recovery. This strategy turned out fruitful, leading to 0.46 g L-1 h-1 volumetric productivity of vanillin of and a production yield of 0.69 gvanillin gferulic acid-1, which are among the highest values reported in the literature for non-modified bacteria.
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Amycolatopsis/metabolismo , Benzaldeídos/química , Reatores Biológicos , Biotecnologia/métodos , Microbiologia Industrial/métodos , Oxigênio/química , Álcoois Benzílicos , Biomassa , Ácidos Cumáricos/química , Meios de Cultura , Glucose/química , Concentração de Íons de Hidrogênio , Cinética , Fenol/química , Ácido Vanílico/químicaRESUMO
OBJECTIVES: To investigate if the distance covered in the Six-Minute Walk Test (6MWT) and in the Incremental Shuttle Walk Test (ISWT) is most strongly explained by walking capacity or cardiorespiratory fitness (CRF) measures in individuals after chronic stroke. MATERIALS AND METHODS: This is a cross-sectional study. Individuals after chronic stroke aged at least 20 years old and able to walk at least 10 minutes independently were included. The distance covered (meters) in the 6 MWT and ISWT (dependent variables), comfortable and fast gait speed obtained by the 10 m walk test (10 mWT) (walking capacity measures; independent variables) and peak oxygen consumption (VO2peak; CRF measure; independent variable) (ml.kg-1.min-1) obtained by the cardiopulmonary exercise test (CPET) were obtained. Linear regression analyses were performed (α = 5%). RESULTS: Fifty individuals (mean age of 55±12 years and mean time after stroke of 67±74 months) were included. Comfortable and fast gait speeds were the variables that most strongly explained the distance covered in the field tests: 6MWT (R² = 0.614, ß = 0.784, p < 0.001 and R² = 0.615, ß = 0.778, p < 0.001, respectively) and ISWT (R² = 0.450, ß = 0.671, p < 0.001 and R² = 0.456, ß = 0.746, p < 0.001, respectively). On the other hand, for the VO2peak, the following models were generated: 6MWT (R² = 0.280, ß = 0.530, p < 0.001) and ISWT (R² = 0.154, ß = 0.393, p = 0.005). CONCLUSIONS: The distance covered in the field tests (6MWT and ISWT) is more suitable to support inferences about the walking capacity than about the CRF of individuals after chronic stroke.
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Aptidão Cardiorrespiratória , Tolerância ao Exercício , Acidente Vascular Cerebral/diagnóstico , Teste de Caminhada , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Velocidade de CaminhadaRESUMO
In this work, we propose the utilization of scCO2 to impregnate ibuprofen into the mcl-PHA matrix produced by Pseudomonas chlororaphis subs. aurantiaca (DSM 19603). The biopolymer has adhesive properties, is biocompatible and has a melting temperature of 45 °C. Several conditions, namely, pressure (15 and 20 MPa) and impregnation time (30 min, 1 h and 3 h) were tested. The highest ibuprofen content (90.8 ± 6.5 mg of ibuprofen/gPHA) was obtained at 20 MPa and 40 °C, for 1 h, with an impregnation rate of 89 mg/(g·h). The processed mcl-PHA samples suffered a plasticization, as shown by the decrease of 6.5 °C in the Tg, at 20 MPa. The polymer's crystallinity was also affected concomitantly with the matrices' ibuprofen content. For all the impregnation conditions tested the release of ibuprofen from the biopolymer followed a type II release profile. This study has demonstrated that the mcl-PHA produced by P. chlororaphis has a great potential for the development of novel topical drug delivery systems.
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Dióxido de Carbono/química , Portadores de Fármacos/química , Ibuprofeno/química , Poli-Hidroxialcanoatos/química , Adesividade , Liberação Controlada de Fármacos , TemperaturaRESUMO
Growth hormone (GH), in addition to its classic actions on growth and metabolism in the body, exerts pleiotropic effects on the immune system, particularly on the thymus. The aim of this study was to evaluate the influence of GH on the interactions between mature thymocytes and the thymic endothelium involved in the migratory process. To this end, fresh thymocytes (C57BL/6 mice) and the thymic endothelial cell line (tEnd.1) were used. In the cell adhesion assay, the GH-treated thymocytes adhered more to tEnd.1 cells. Additionally, there was an improvement in the deposition of fibronectin by tEnd.1 cells when co-cultured with GH-pre-treated thymocytes. Furthermore, GH induced thymocyte F-actin polymerization. In the transendothelial migration assay, a large number of GH-treated thymocytes, mainly the CD4-CD8+ subset, migrated towards the endothelium under the stimulus of insulin-like growth factor 1. In conclusion, we demonstrated the positive actions of GH in thymocyte/thymic endothelium interactions, including transendothelial migration.
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Hormônio do Crescimento , Hormônio do Crescimento Humano , Animais , Diferenciação Celular , Células Endoteliais , Camundongos , Camundongos Endogâmicos C57BL , TimócitosRESUMO
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-3HV)) copolymer's properties depend on (i) the molar fraction of comonomers, (ii) the overall molar mass, and (ii) the chemical compositional distribution. This work aims at providing a better understanding of the effect of the P(3HB-3HV) molecular structure, produced from mixed cultures and waste feedstock, on copolymer crystallization and tensile properties. Conventional biopolymer characterization methods (differential scanning calorimetry, X-ray diffraction, and polarized optical microscopy) were coupled to both classical one-dimensional (1H and 13C) and advanced two-dimensional (diffusion-ordered spectroscopy (DOSY) and 1H/13C heteronuclear single quantum coherence (HSQC)) nuclear magnetic resonance (NMR) spectroscopy techniques. The obtained results evidenced that (i) a high-quality copolymer could be achieved, even from a waste feedstock; (ii) increasing the 3HV content displayed a positive impact on P(3HB-3HV) mechanical properties only if good interactions between 3HB and 3HV moieties were established; and (iii) the purification process eliminated short-length 3HV-rich chains and promoted homogeneous co-crystallization. Such optimized microstructures enabled the maximal stress and strain at break to be increased by +41.2 and +100%, respectively.
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Hidroxibutiratos , Poliésteres , Cristalização , Estrutura MolecularRESUMO
PURPOSE: To investigate the feasibility and safety of a randomized controlled trial that performed cardiopulmonary exercise testing and 12 weeks of aerobic treadmill training in individuals in the chronic phase after stroke. METHODS: The following data were recorded: number of individuals contacted to participate, that attended in the evaluation session, and that were included (recruited) in the study; retention, attendance and adherence rates; reasons for exclusion, withdrawal, non-attendance and non-completing exercise; adverse events. RESULTS: From 230 individuals that were contacted, 39 (17%) attended the evaluation session and 22 (9.6%) were recruited in the study, 11 in each group (control and experimental). The main source of recruitment was other research projects (43.5%). The main reason for exclusion was unavailability (22%). Six out of 39 individuals (15.4%) that attended in the evaluation session were not able to perform the cardiopulmonary exercise testing. All subjects included showed a respiratory exchange ratio ≥1.0 (considered as maximal effort in the CPET). Retention rate was 81% and the main reason of withdrawal was unavailability (75%). The overall attendance rate was 88% and the main reason for non-attendance was illness/sickness (20.8%). The adherence rate was 99% and the reasons for non-completing sessions were illness/sickness (60%) or delay (40%). No serious adverse events occurred. CONCLUSION: Recruitment rate was low, retention rate was moderate, attendance and adherence rates were high. No serious adverse events occurred. It was feasible and safe to execute a randomized clinical trial that performed cardiopulmonary exercise testing and 12 weeks of aerobic treadmill training.
Assuntos
Reanimação Cardiopulmonar , Aptidão Cardiorrespiratória , Terapia por Exercício , Tolerância ao Exercício , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Brasil , Terapia por Exercício/efeitos adversos , Estudos de Viabilidade , Humanos , Cooperação do Paciente , Seleção de Pacientes , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Tamanho da Amostra , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral/efeitos adversos , Fatores de Tempo , Resultado do TratamentoRESUMO
This study aimed to evaluate the metabolic, productive, and carcass parameters of feedlot lambs fed high-concentrate diets with cottonseed associated with calcium lignosulfonate. Treatments consisted of diets including whole cottonseed, crushed cottonseed, whole cottonseed with lignosulfonate (100 g/kg), crushed cottonseed with lignosulfonate (100 g/kg), and a control diet without cottonseed. Thirty ½ Dorper ½ Santa Inês, non-castrated male lambs with an average live weight of 24.9 ± 3.6 kg and an average age of 3.5 months were evaluated in a completely randomized design. There was no effect (P > 0.05) on the intakes of dry matter, organic matter, crude protein, and non-fibrous carbohydrates. The crushing of cottonseed and association with lignosulfonate increased (P < 0.01) the intake and digestibility of ether extract. No effect was observed (P > 0.05) for the concentrations of urine and plasma urea N, which averaged 616.2 and 108.6 mg/dL, respectively. There was a change (P < 0.01) in nitrogen balance for digested N in g/day. There was no effect (P > 0.05) on the urinary concentration of purine derivatives, except for uric acid excretions (P < 0.05). Lignosulfonate associated with cottonseed provided an average daily gain of 0.293 kg/day, which was higher than the 0.226 kg/day obtained without lignosulfonate, but lower than control (0.302 kg/day), which also showed higher values of carcass yield. High-concentrate diets formulated without cottonseed improve lamb production performance. The use of high-concentrate diets with cottonseed associated with calcium lignosulfonate provides greater weight gains in lambs.