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Essential thrombocythemia is the category of myeloproliferative syndromes, generally characterized by a group of clonal stem cell diseases that present a disturbance in the growth of one or more sets of hematopoietic cells. All long clinical treatment, patients may experience gastrointestinal disorders and other metabolic processes that can lead to weight loss and malnutrition. Cytokine is involved in the control of appetite, digestive, and metabolic processes in the body, it can be assumed that increased stimulation could impair the control of these processes leading to loss of body mass. Effective and systematic nutritional intervention is required to ensure patient compliance with treatment and improved nutritional status.
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Desnutrição , Estado Nutricional , Trombocitemia Essencial , Redução de Peso , Humanos , Desnutrição/terapia , Cooperação do Paciente , Trombocitemia Essencial/terapia , Trombocitemia Essencial/dietoterapia , Redução de Peso/fisiologia , Guias de Prática Clínica como AssuntoRESUMO
AIMS: The concomitant increase in skeletal muscle mass (SMM) and decrease in fat mass has been termed body recomposition. This study aimed to analyze the influence of pre-training levels of fat mass on body recomposition, muscular strength, and (phase angle) PhA after 24 weeks of resistance training (RT) in older women. METHODS: Data from 99 older women (68.6 ± 5.7 years, 65.7 ± 8.6 kg, 155.1 ± 5.8 cm, 27.2 ± 3.1 kg/m2) was retrospectively analyzed. Participants were separated into tertiles according to the amount of fat mass at baseline as follows: low fat mass (L-FM, n = 33), moderate fat mass (M-FM, n = 33), and high fat mass (H-FM, n = 33). The participants underwent a RT program consisting of eight exercises, three sets per exercise, with a load between 8 and 15 RM, performed three times per week for 24 weeks. The SMM and fat mass were evaluated by dual-energy X-ray absorptiometry (DXA). Body recomposition was determined by the composite Z-score of changes in SMM and fat mass. One repetition maximum (1RM) tests in chest press, knee extension, and preacher curl were assessed to verify muscular strength. Bioimpedance was used to determine phase angle. RESULTS: Results indicated that after the RT period, a greater positive body recomposition was observed in the L-FM group than in M-FM and H-FM groups. Moreover, all groups increased muscular strength and phase angle with no significant difference among groups (P > 0.05). CONCLUSION: The present study results suggest that the initial amount of fat mass influences the body recomposition induced by RT in older women, with those with lower pre-training fat mass levels presenting higher levels of body recomposition. However, improvements in muscular strength and phase angle are not dependent on the amount of initial fat mass in older women.
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Composição Corporal , Treinamento Resistido , Feminino , Humanos , Idoso , Composição Corporal/fisiologia , Treinamento Resistido/métodos , Estudos Retrospectivos , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Força Muscular/fisiologiaRESUMO
A heteroscedastic regression based on the odd log-logistic Marshall-Olkin normal (OLLMON) distribution is defined by extending previous models. Some structural properties of this distribution are presented. The estimation of the parameters is addressed by maximum likelihood. For different parameter settings, sample sizes and some scenarios, various simulations investigate the performance of the heteroscedastic OLLMON regression. We use residual analysis to detect influential observations and to check the model assumptions. The new regression explains the mass loss of different wood species in civil construction in Brazil.
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BACKGROUND: Body weight changes occur frequently during advanced stages of Spinocerebellar Ataxia type 2 (SCA2), nevertheless limited information exists on biomarkers of nutritional status of these patients. OBJECTIVE.: To assess changes in surrogate nutritional markers of SCA2 patients; to explore their associations with expanded CAG repeats and disease severity. METHODS: One-hundred-thirteen SCA2 patients and 50 healthy controls underwent a comprehensive anthropometrical and biochemical assessment protocol of the nutritional status. Neurological and genotype assessments were also performed. RESULTS: A decrease in weight, body mass index (BMI), cutaneous skinfold thickness, fat mass, arm muscle circumference, calf circumference and skeletal muscle mass was observed in SCA2 patients compared to the controls. The total/HDL cholesterol ratio was significantly reduced in patients. BMI was correlated with the age at onset. Overall, anthropometric measures were correlated with clinical markers of disease severity and were more evident in severe and moderate cases. CONCLUSIONS: Using anthropometric measures in the assessment of the nutritional status of SCA2 patients might provide hints about pathophysiological mechanisms that underlie metabolic abnormalities in SCA2. Anthropometric are close related with disease severity and progression, and trigger preventive therapies aimed to ameliorate weight loss and wasting in these patients.
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Ataxias Espinocerebelares , Estudos de Coortes , Estudos Transversais , Humanos , Índice de Gravidade de Doença , Ataxias Espinocerebelares/genética , Redução de PesoRESUMO
Lack of mechanical load leads to skeletal muscle atrophy, and one major underlying mechanism involves the myostatin pathway that negatively regulates protein synthesis and also activates Atrogin-1/MAFbx and MuRF1 genes. In hindlimb immobilization, leucine was observed to attenuate the upregulation of the referred atrogenes, thereby shortening the impact on fiber cross-sectional area, nonetheless, the possible connection with myostatin is still elusive. This study sought to verify the impact of leucine supplementation on myostatin expression. Male Wistar rats were supplemented with leucine and hindlimb immobilized for 3 and 7 days, after which soleus muscles were removed for morphometric measurements and analyzed for gene and protein expression by real-time PCR and Western blotting, respectively. Muscle wasting was prominent 7 days after immobilization, as expected, leucine feeding mitigated this effect. Atrogin-1/MAFbx gene expression was upregulated only after 3 days of immobilization, and this effect was attenuated by leucine supplementation. Atrogin-1/MAFbx protein levels were elevated after 7 days of immobilization, which leucine supplementation was not able to lessen. On the other hand, myostatin gene expression was upregulated in immobilization for 3 and 7 days, which returned to normal levels after leucine supplementation. Myostatin protein levels followed gene expression at a 3-day time point only. Follistatin gene expression was upregulated during immobilization and accentuated by leucine after 3 days of supplementation. Concerning protein expression, follistatin was not altered neither by immobilization nor in immobilized animals treated with leucine. In conclusion, leucine protects against skeletal muscle mass loss during disuse, and the underlying molecular mechanisms appear to involve myostatin inhibition and Atrogin-1 normalization independently of follistatin signaling.
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Exercise is an effective strategy for preventing and treating obesity and its related cardiometabolic disorders, resulting in significant loss of body fat mass, white adipose tissue browning, redistribution of energy substrates, optimization of global energy expenditure, enhancement of hypothalamic circuits that control appetite-satiety and energy expenditure, and decreased systemic inflammation and insulin resistance. Novel exercise-inducible soluble factors, including myokines, hepatokines, and osteokines, and immune cytokines and adipokines are hypothesized to play an important role in the body's response to exercise. To our knowledge, no review has provided a comprehensive integrative overview of these novel molecular players and the mechanisms involved in the redistribution of metabolic fuel during and after exercise, the loss of weight and fat mass, and reduced inflammation. In this review, we explain the potential role of these exercise-inducible factors, namely myokines, such as irisin, IL-6, IL-15, METRNL, BAIBA, and myostatin, and hepatokines, in particular selenoprotein P, fetuin A, FGF21, ANGPTL4, and follistatin. We also describe the function of osteokines, specifically osteocalcin, and of adipokines such as leptin, adiponectin, and resistin. We also emphasize an integrative overview of the pleiotropic mechanisms, the metabolic pathways, and the inter-organ crosstalk involved in energy expenditure, fat mass loss, reduced inflammation, and healthy weight induced by exercise.
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Composição Corporal/fisiologia , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Peptídeos/fisiologia , Adipocinas/fisiologia , Tecido Adiposo/metabolismo , Animais , Regulação do Apetite/fisiologia , Osso e Ossos/metabolismo , Humanos , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Redes e Vias Metabólicas/fisiologia , Músculo Esquelético/metabolismo , Obesidade , Hormônios Peptídicos/fisiologia , Redução de PesoRESUMO
RESUMEN Se evaluó la durabilidad natural de la madera de O, pyramidale en el municipio de Atrato, Chocó. En cada uno de los ambientes: bajo dosel de árboles BDA, libre exposición LE y bajo sombra de plástico negro BS, se empleó un diseño de bloques completamente al azar conformado por tres tratamientos y tres repeticiones de 30 probetas cada uno. Los resultados del análisis de varianza sugieren que no existe diferencia significativa para el contenido de humedad y la pérdida de masa. Se experimentó un aumento en el contenido de humedad de 119,32% y 90,63% de las probetas ubicadas a LE y BS, respectivamente. Basados en estas características, la madera de O. pyramidale se ubica en la categoría poco resistente, por lo que se puede inferir que, no es apta para construcciones que queden en contacto directo con el suelo, donde es afectada por diversos agentes de biodeterioro.
ABSTRACT The natural durability of O, pyramidalewood was evaluated in the municipality of Atrato, Chocó. In each of the environmental conditions: under canopy of UCT trees, free exposure FE and under black plastic shade UBP a completely random block design was used, consisting of three treatments and three repetitions of 30 wood samples each. The results of the analysis of variance suggest that there is no significant difference for moisture content and mass loss. An increase in moisture content of 119.32% and 90.63% of the wood specimens located at LE and BS, respectively, was observed. Based on these characteristics, O. pyramidalewood is located in the low resistance category, so it can be inferred that it is not suitable for constructions in direct contact with the ground, where it is affected by various biodeteriorating agents.
RESUMO A durabilidade natural da madeira O. pyramidalefoi avaliada no munic'pio de Atrato, Chocó. Em cada um dos ambientes: sob uma copa de árvores BDA, exposição livre LE e sob uma sombra de plástico preto BS, foi utilizado um desenho de bloco completamente aleatório, consistindo em três tratamentos e três repetições de 30 espécimes cada um. Os resultados da análise de variância sugerem que não há diferença significativa para o conteúdo de umidade e perda de massa. Um aumento no teor de umidade de 119,32% e 90,63% foi experimentado por peças de teste localizadas no LE e na BS, respectivamente. Com base nestas caracter'sticas, a madeira O. pyramidaleestá na categoria de baixa resistência, pelo que se pode inferir que não é adequada para construções que estejam em contacto directo com o solo, onde é afectada por vários agentes biodeteriorantes.
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Colorectal cancer (CRC) is the third most commonly diagnosed cancer globally and the second cancer in terms of mortality. The prevalence of sarcopenia in patients with CRC ranges between 12%-60%. Sarcopenia comes from the Greek "sarx" for flesh, and "penia" for loss. Sarcopenia is considered a phenomenon of the aging process and precedes the onset of frailty (primary sarcopenia), but sarcopenia may also result from pathogenic mechanisms and that disorder is termed secondary sarcopenia. Sarcopenia diagnosis is confirmed by the presence of low muscle quantity or quality. Three parameters need to be measured: muscle strength, muscle quantity and physical performance. The standard method to evaluate muscle mass is by analyzing the tomographic total cross-sectional area of all muscle groups at the level of lumbar 3rd vertebra. Sarcopenia may negatively impact on the postoperative outcomes of patients with colorectal cancer undergoing surgical resection. It has been described an association between sarcopenia and numerous poor short-term CRC outcomes like increased perioperative mortality, postoperative sepsis, prolonged length of stay, increased cost of care and physical disability. Sarcopenia may also negatively impact on overall survival, disease-free survival, recurrence-free survival, and cancer-specific survival in patients with non-metastatic and metastatic colorectal cancer. Furthermore, patients with sarcopenia seem prone to toxic effects during chemotherapy, requiring dose deescalations or treatment delays, which seems to reduce treatment efficacy. A multimodal approach including nutritional support (dietary intake, high energy, high protein, and omega-3 fatty acids), exercise programs and anabolic-orexigenic agents (ghrelin, anamorelin), could contribute to muscle mass preservation. Addition of sarcopenia screening to the established clinical-pathological scores for patients undergoing oncological treatment (chemotherapy, radiotherapy or surgery) seems to be the next step for the best of care of CRC patients.
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Due to the difficulty of performing research protocols that reproduce human skeletal muscle disuse conditions, an experimental animal model of "hindlimb suspension" (or hindlimb unloading) was developed. This method was created in the 1970s and utilizes rats and mice to mimic space flight and bed rest in humans. It provides an alternative to investigate mechanisms associated with skeletal muscle mass loss and interventions designed to attenuate atrophy induced by hindlimb unloading. The mentioned protocol also allows investigating quality of bones and changes in several physiological parameters such as blood pressure, heart rate, plasma or tissue lipid composition, and glycemia.
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Atrofia/sangue , Elevação dos Membros Posteriores/métodos , Músculo Esquelético/fisiopatologia , Atrofia Muscular/sangue , Animais , Atrofia/genética , Atrofia/fisiopatologia , Pressão Sanguínea , Humanos , Lipídeos/sangue , Músculo Esquelético/metabolismo , Atrofia Muscular/fisiopatologia , Ratos , RoedoresRESUMO
The objectives of the present work were control the decay incidence and ripening of wounded fruits by the relative humidity management during the storage. Fruits were allocated in mini experimental chambers at the temperature of 1°C during 5 months. Was verified a significant interaction on ethylene production after 2 and 6 days of shelf life at 20°C. On the evaluation carried out after 6 days, wounded fruits stored under LRH showed lower ethylene production. There was higher mass loss in wounded fruits stored in HRH. Wounded fruits showed high decay incidence. The LRH is not an efficient method to control decay incidence in wounded fruits, but maintain higher flesh firmness, lower ethylene production and respiration rate.
Objetivou-se neste trabalho controlar a ocorrência de podridões e o amadurecimento de frutos com ferimentos pelo manejo da umidade relativa (UR) durante o armazenamento. Os frutos foram acondicionados em minicâmaras experimentais na temperatura de 1°C durante um período de cinco meses. Observou-se uma interação significativa para produção de etileno aos dois e seis dias de exposição a 20°C. Na análise aos seis dias, frutos com ferimento em baixa umidade relativa (BUR) apresentaram menor produção de etileno. Houve maior perda de massa em frutos com ferimento em alta UR. Frutos com ferimento apresentaram elevados índices de podridão. O uso de BUR não é eficiente no controle de podridões em frutos com ferimentos, porém ela mantém maior firmeza de polpa, menor produção de etileno e taxa respiratória.
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Malus , Etilenos , Armazenamento de Alimentos , UmidadeRESUMO
Introducción: está demostrado que la donación de sangre total repetitiva conduce a una deficiencia de hierro, dependiendo fundamentalmente de la frecuencia de donaciones. Sin embargo, el posible efecto que pudiera inducir la plasmaféresis regular sobre la concentración de hemoglobina es un aspecto poco reportado.Objetivo: determinar el comportamiento de esta variable y estimar las pérdidas de masa de eritrocitos en donantes de plasmaféresis intensiva nivel 2.Métodos: se realizó un estudio descriptivo longitudinal a través de la revisión de 100 historias clínicas de donantes seleccionados aleatoriamente, para recoger resultados de la determinación de hemoglobina y del hematocrito durante un ciclo de 24 donaciones. Las pérdidas de masa de eritrocito fueron estimadas a través de la medición del volumen y del hematocrito de la sangre total contenida en set de plasmaféresis al finalizar la donación de plasma, sumando a ello la cantidad de sangre total extraída para los estudios de laboratorio.Rsultados: se encontró que la concentración promedio de hemoglobina no presentó modificaciones estadísticamente significativas para ambos sexos ni para el grupo total. La pérdida de eritrocitos en un proceso de plasmaféresis fue de aproximadamente 18 mL (9.25 mL remanentes en el set de plasmaféresis y 8.86 mL para muestras de laboratorio), muy cercanos a los 25 mL reglamentados por el Centro para el Control Estatal de la Calidad de los Medicamentos en Cuba (CECMED).Conclusiones: aunque la concentración de hemoglobina y el hematocrito son fácilmente estimadas, su sensibilidad no es buena para la evaluación de la deficiencia de hierro en etapas en que solo sus reservas están disminuidas. La incorporación de otros exámenes de laboratorio más sensibles contribuiría a mejorar la vigilancia de los niveles de hemoglobina en este grupo de individuos(AU)
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Índices de Eritrócitos , Doadores de Sangue , Avaliação em Saúde/métodos , Epidemiologia Descritiva , Estudos LongitudinaisRESUMO
INTRODUCCIÓN: está demostrado que la donación de sangre total repetitiva conduce a una deficiencia de hierro, dependiendo fundamentalmente de la frecuencia de donaciones. Sin embargo, el posible efecto que pudiera inducir la plasmaféresis regular sobre la concentración de hemoglobina es un aspecto poco reportado. OBJETIVO: determinar el comportamiento de esta variable y estimar las pérdidas de masa de eritrocitos en donantes de plasmaféresis intensiva nivel 2. MÉTODOS: se realizó un estudio descriptivo longitudinal a través de la revisión de 100 historias clínicas de donantes seleccionados aleatoriamente, para recoger resultados de la determinación de hemoglobina y del hematocrito durante un ciclo de 24 donaciones. Las pérdidas de masa de eritrocito fueron estimadas a través de la medición del volumen y del hematocrito de la sangre total contenida en set de plasmaféresis al finalizar la donación de plasma, sumando a ello la cantidad de sangre total extraída para los estudios de laboratorio. RESULTADOS: se encontró que la concentración promedio de hemoglobina no presentó modificaciones estadísticamente significativas para ambos sexos ni para el grupo total. La pérdida de eritrocitos en un proceso de plasmaféresis fue de aproximadamente 18 mL (9.25 mL remanentes en el set de plasmaféresis y 8.86 mL para muestras de laboratorio), muy cercanos a los 25 mL reglamentados por el Centro para el Control Estatal de la Calidad de los Medicamentos en Cuba (CECMED). CONCLUSIONES: aunque la concentración de hemoglobina y el hematocrito son fácilmente estimadas, su sensibilidad no es buena para la evaluación de la deficiencia de hierro en etapas en que solo sus reservas están disminuidas. La incorporación de otros exámenes de laboratorio más sensibles contribuiría a mejorar la vigilancia de los niveles de hemoglobina en este grupo de individuos(AU)
INTRODUCTION: A close relation between repetitive whole blood donation and iron deficiency has been demonstrated, mainly depending on the frequency of donations. However, the possible effect on hemoglobin concentration that regular plasmapheresis could induce has been scarcely reported. AIM: Determine the behavior of this variant and to estimate red blood cell mass loss in intensive plasmapheresis donor level 2. METHODS: A longitudinal descriptive study was carried out reviewing medical records of 100 randomly selected donors to collect results of the determination of hemoglobin and hematocrit during a cycle of 24 donations. Red cell mass loss was estimated by measuring of volume and hematocrit of whole blood contained in the plasmapheresis set at the end of plasma donation and adding the total amount of blood collected for laboratory tests. RESULTS: Average concentration of hemoglobin showed no statistically significant changes for both, female or male donors. The loss of red blood cell mass in a process of plasma was approximately 18 mL (9.25 mL remaining on the plasma set and 8.86 mL for laboratory tests) which was very close to the limit of 25 mL according to Centro para el Control Estatal de la Calidad de los Medicamentos en Cuba (CECMED) regulations. CONCLUSIONS: Even when hemoglobin and hematocrit concentration are easily estimated, sensitivity is not good for the evaluation of iron deficiency in periods in which only stores are diminished. The inclusion of other more precise laboratory tests will contribute to a better surveillance of haemoglobin levels in this group of individuals(AU)
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Dose-dependent positive effects on hatchability and hatchling weight have been attributed to ascorbic acid (AA) when eggs were submitted or not to intermittent heat stress during incubation. Fertile breeder (Cobb(r)) eggs were used to determine if the pre-incubation injection of AA in ovo affects the incubation and hatchling quality of egg incubated under thermoneutral or intermittent heat stress conditions. Eggs were not injected or injected with 0, 2,4, or 6% AA/100µL water and incubated at continuous thermoneutral (37.5ºC) or hot (39.0ºC) temperature. Eggshell temperature (EST) increased in the second half of the incubation period in all experimental groups. The EST of non-injected eggs and of those injected with water was higher when incubated at 39°C than at 37.5°C, but EST was not different among eggs injected with AA. Egg mass loss and eggshell conductance were higher in the eggs incubated at 39°C than at 37.5°C.Hatchability was lower in the eggs injected with AA. Liver and yolk sac weights were higher, whereas heart and liver weights were lower in hatchlings from eggs incubated at 39°C; however, hatchling weight was not affected by incubation temperature. The results showed that AA doses affected egg conductive heat loss and hatchability, and that they did not minimize the effects of high incubation temperature on liver and heart development.(AU)
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Animais , Casca de Ovo/anormalidades , Casca de Ovo/crescimento & desenvolvimento , Ácido Ascórbico/efeitos adversos , Ácido Ascórbico/análise , Galinhas/fisiologiaRESUMO
Dose-dependent positive effects on hatchability and hatchling weight have been attributed to ascorbic acid (AA) when eggs were submitted or not to intermittent heat stress during incubation. Fertile breeder (Cobb(r)) eggs were used to determine if the pre-incubation injection of AA in ovo affects the incubation and hatchling quality of egg incubated under thermoneutral or intermittent heat stress conditions. Eggs were not injected or injected with 0, 2,4, or 6% AA/100µL water and incubated at continuous thermoneutral (37.5ºC) or hot (39.0ºC) temperature. Eggshell temperature (EST) increased in the second half of the incubation period in all experimental groups. The EST of non-injected eggs and of those injected with water was higher when incubated at 39°C than at 37.5°C, but EST was not different among eggs injected with AA. Egg mass loss and eggshell conductance were higher in the eggs incubated at 39°C than at 37.5°C.Hatchability was lower in the eggs injected with AA. Liver and yolk sac weights were higher, whereas heart and liver weights were lower in hatchlings from eggs incubated at 39°C; however, hatchling weight was not affected by incubation temperature. The results showed that AA doses affected egg conductive heat loss and hatchability, and that they did not minimize the effects of high incubation temperature on liver and heart development.
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Animais , Casca de Ovo/anormalidades , Casca de Ovo/crescimento & desenvolvimento , Ácido Ascórbico/análise , Ácido Ascórbico/efeitos adversos , Galinhas/fisiologiaRESUMO
Knowledge of the respiration rate during the storage is important in the evaluation of the post-harvest tools that preserve fruit quality, and also for the provision of information for the development of new packages. This work aimed to evaluate the respiration rate of 'Golden' Carica papaya stored under refrigeration and controlled atmosphere conditions. The fruit was kept at 13 °C in controlled atmospheres comprising three levels of O2 (20.8 %, 6 %, 3 %) with a minimum level of CO2 (0.1 %); and three levels of CO2 (0.1 %, 6 %, 12 %) with the lowest level of O2 (3 %). Measurements were taken at intervals of 5 days during the 30 days of storage. The mass loss and the peel color of the fruits were identified at the end of the storage period. The fruit maintained under 'normal' atmosphere conditions (20.8 % O2 and 0.1 % CO2) increased its respiration rate after the 10th day, reaching after 30 days 4.3 times the initial value. After 30 days in 3 % O2, the respiration rate was 2.9 times less than in the normal atmosphere. The decrease in respiration rate minimized the mass loss in fruit stored at 3 % O2, but it was unaffected by increasing levels of CO2.(AU)
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Carica/fisiologia , Alimentos Resfriados , Taxa Respiratória , Qualidade dos AlimentosRESUMO
Knowledge of the respiration rate during the storage is important in the evaluation of the post-harvest tools that preserve fruit quality, and also for the provision of information for the development of new packages. This work aimed to evaluate the respiration rate of 'Golden' Carica papaya stored under refrigeration and controlled atmosphere conditions. The fruit was kept at 13 °C in controlled atmospheres comprising three levels of O2 (20.8 %, 6 %, 3 %) with a minimum level of CO2 (0.1 %); and three levels of CO2 (0.1 %, 6 %, 12 %) with the lowest level of O2 (3 %). Measurements were taken at intervals of 5 days during the 30 days of storage. The mass loss and the peel color of the fruits were identified at the end of the storage period. The fruit maintained under 'normal' atmosphere conditions (20.8 % O2 and 0.1 % CO2) increased its respiration rate after the 10th day, reaching after 30 days 4.3 times the initial value. After 30 days in 3 % O2, the respiration rate was 2.9 times less than in the normal atmosphere. The decrease in respiration rate minimized the mass loss in fruit stored at 3 % O2, but it was unaffected by increasing levels of CO2.
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Alimentos Resfriados , Carica/fisiologia , Qualidade dos Alimentos , Taxa RespiratóriaRESUMO
A signature of globalization is the prevalence of exotic trees along reforested urban and rural riparian zones in the Neotropics, but little is known about the instream processing of its leaf litter. In this study, leaf litter breakdown rates were measured during 35 days using mesh bags within a reference headwater stream for seven exotic and three native tree species commonly used in urban and rural reforestation. Artocarpus altilis, Schefflera actinophylla and Terminalia catappa scored the highest mass loss rates (>85 %; mean life: t50.
Una de las señales más evidentes de la globalización es la prevalencia de especies de árboles exóticos a lo largo de las zonas ribereñas urbanas y rurales del Neotrópico, pero poco se sabe sobre el procesamiento de su hojarasca dentro de las quebradas. En este estudio se midieron las tasas de pérdida de masa de la hojarasca usando bolsas de angeo en una quebrada de referencia durante 35 días, para siete especies exóticas y tres nativas comúnmente usadas en la reforestación urbana y rural. Artocarpus altilis, Schefflera actinophylla y Terminalia catappa obtuvieron las mayores tasas de pérdida de masa (>85 %; vida media: t50.
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The aim of this study is to evaluate the kinetics of aerobic decomposition of Saccharum officinarum and Talauma ovata leaves. For each species, decomposition chambers (leaves and water) were set up, which were maintained under controlled conditions. Each sampling day (1, 7, 15, 30, 39, 58, 72 and 90 days), the concentrations of total organic carbon, pH and electrical conductivity (EC) were determined in the dissolved fraction, while the mass and cell wall fractions (CWF) were determined in the particulate fraction. The pH stabilization of the chambers with T. ovata and S. officinarum leaves occurred in alkaline (ca. 8 - 8.5) and close to the neutrality (ca. 7 - 7.5) environment, respectively. The EC values were on average 1.6 times higher in incubations with T. ovata leaves. The mass loss did not differ between the species (mean = 53.85%), however the decay coefficient was higher for S. officinarum (k4 = 0.007 day-1) than for T. ovata (k4 = 0.005 day-1) leaves. The CWF mass loss (mean = 50.16%) and their coefficient (0.0090 day-1) were similar. S. officinarum decomposed faster due to its high concentrations of energetic compounds of interest to the microbiota. The slower decomposition of T. ovata may have occurred due to the presence of secondary compounds with negative effects to the microorganisms.
O objetivo deste estudo foi avaliar as cinéticas da decomposição aeróbia de folhas de Talauma ovata e Saccharum officinarum. Para cada espécie foram montadas câmaras de decomposição (folhas e água) que foram mantidas sob condições controladas. A cada dia amostral (1, 7, 15, 30, 39, 58, 72 e 90 dias), as concentrações de carbono orgânico total, pH e condutividade elétrica (CE) foram determinadas na fração dissolvida, enquanto a massa e as frações de parede celular (FPC) foram determinadas na fração particulada. A estabilização do pH das câmaras com folhas de T. ovata e S. officinarum ocorreram em meio básico (ca. 8 - 8,5) e próximo à neutralidade (ca. 7 - 7,5), respectivamente. Os valores de CE foram em média 1,6 vezes maiores nas incubações com folhas de T. ovata. A perda de massa não diferiu entre as espécies (média = 53,85%). No entanto, o coeficiente de decaimento foi maior para as folhas de S. officinarum (k4 = 0,007 dia-1) que para T. ovata (k4 = 0,005 dia-1). As perdas de massa da FPC (média = 50,16%) e seus respectivos coeficientes (0,0090 dia-1) foram similares. S. officinarum decompôs mais rapidamente devido às elevadas concentrações de compostos energéticos de interesse para a microbiota. A decomposição mais lenta de T. ovata pode ter ocorrido pela presença de compostos secundários com efeitos negativos sobre os micro-organismos.
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Água , Folhas de Planta , Carbono-Carbono LiasesRESUMO
This study analyzed the weight loss and surface roughness caused in Plexiglass specimens by conventional dentifrices (Sorriso, Colgate and Close Up) and specific dentifrices used for cleaning of dentures (Corega and Dentu Creme). Plexiglass specimens were divided into 6 groups (n=6) including: a control (distilled water - DW) and experimental groups. Brushing was performed in a toothbrushing machine with a soft brush and a dentifrice suspension and DW according to different brushing times (50, 100, 200 and 250 min -18,000, 36,000, 72,000 and 90,000 cycles, respectively, calculated to correspond to 1, 2, 4 and 5 years of regular brushing). The results of weight loss and surface roughness were analyzed by ANOVA and Tukey’s test at 5% significance level. In all tested times, the effect of DW was insignificant. Dentifrices differed significantly from DW in the initial period. Corega dentifrice caused greater mass loss in all studied times, followed by Close Up. Dentifrices resulted in a surface roughness similar to the DW at 50 min. In the other times, Sorriso, Colgate and Corega caused more surface roughness than DW. In conclusion, specific dentifrices caused larger mass loss and lower surface roughness as conventional dentifrice.
Este estudo analisou a perda de massa e rugosidade superficial causadas em corpos de prova de Plexiglass por dentifrícios convencionais (Sorriso, Colgate e Close Up) e específicos (Corega e Dentu Creme) para higienização de próteses totais. Os corpos de prova de Plexiglass foram distribuidos em 6 grupos (n=6), sendo um controle (água destilada - AD) e grupos experimentais. A escovação foi realizada em máquina de escovação com escovas macias e suspensões de dentifrícios ou AD, de acordo com os diferentes tempos de escovação (50, 100, 200 e 250 min -18.000, 36.000, 72.000 e 90.000 ciclos, respectivamente, calculados para corresponder a 1, 2, 4 e 5 anos de escovação regular). Os resultados de perda de massa e rugosidade superficial foram analisados por meio de ANOVA e teste de Tukey com 5% de significância. Em todos os tempos analisados, a AD teve efeito insignificante. Os dentifrícios diferiram significativamente da AD no período inicial. O dentifrício Corega causou maior perda de massa em todos os tempos estudados, seguido por Close Up. No tempo de 50 min, todos os dentifrícios causaram rugosidade superficial semelhante à AD. Nos outros tempos, Sorriso, Colgate e Corega causaram maior rugosidade superficial em relação à AD. Conclui-se que os dentifrícios específicos causaram maior perda de massa, porém menor rugosidade superficial que os dentifrícios convencionais.
Assuntos
Prótese Total , Dentifrícios/química , Higienizadores de Dentadura/química , Abrasão Dentária , Escovação Dentária , Análise de Variância , Teste de Materiais , Polimetil Metacrilato , Propriedades de SuperfícieRESUMO
Se estima que dos terceras partes de los pacientes con cáncer sufren anorexia o pérdida significativa de apetito, lo que conduce a pérdida acentuada de peso y a desnutrición grave (caquexia), una de las principales causas contribuyentes de la muerte. Se ha observado que el síndrome de anorexia-caquexia en cáncer difiere de la desnutrición simple, si bien aún no se conocen los mecanismos exactos que lo ocasionan. Diversas hipótesis proponen que la patogénesis es multicausal, destacándose diversas características del tumor, del huésped y variables del tratamiento. Desafortunadamente, con frecuencia la pérdida acentuada de peso representa para el paciente la progresión del proceso de la enfermedad, lo que puede tener repercusiones significativas en su calidad de vida y en sus interacciones familiares y sociales. Se lleva a cabo una revisión bibliográfica de los procesos etiológicos del síndrome, así como de las posibles medidas terapéuticas y farmacológicas.
Approximately two thirds of cancer patients at advanced stages of the disease suffer from anorexia, which leads to significant weight loss and progressive cachexia, an important factor that contributes to death. It has been observed that cancer cachexia differs from simple starvation, although the exact mechanisms associated with cancer cachexia are not well known. Several theories regarding its pathogenesis point to a complex mixture of tumor, host and treatment variables. Unfortunately, the wasting syndrome also constitutes for the patient, a progression of the cancer process, significantly affecting quality of life and social interactions. Treatable causes should be identified and treated. Knowledge of the mechanisms underlying the effects of caquexia on the patient may play a role in identifying treatment measures targetted to muscle wasting and to maintain body strength. In this article we review the main features and mechanisms of the anorexia-cachexia syndrome in patients with cancer.