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Planetary rings are observed not only around giant planets1, but also around small bodies such as the Centaur Chariklo2 and the dwarf planet Haumea3. Up to now, all known dense rings were located close enough to their parent bodies, being inside the Roche limit, where tidal forces prevent material with reasonable densities from aggregating into a satellite. Here we report observations of an inhomogeneous ring around the trans-Neptunian body (50000) Quaoar. This trans-Neptunian object has an estimated radius4 of 555 km and possesses a roughly 80-km satellite5 (Weywot) that orbits at 24 Quaoar radii6,7. The detected ring orbits at 7.4 radii from the central body, which is well outside Quaoar's classical Roche limit, thus indicating that this limit does not always determine where ring material can survive. Our local collisional simulations show that elastic collisions, based on laboratory experiments8, can maintain a ring far away from the body. Moreover, Quaoar's ring orbits close to the 1/3 spin-orbit resonance9 with Quaoar, a property shared by Chariklo's2,10,11 and Haumea's3 rings, suggesting that this resonance plays a key role in ring confinement for small bodies.
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Our previous studies have shown that methionine supplementation could help to attenuate the effects of heat stress on the metabolism of broiler chickens. Here we investigated for the first time the effects of methionine supplementation in the form of DL-methionyl-DL-methionine on broilers subjected to heat stress during the growth phase. Broilers were divided into two groups; one group was reared under thermoneutral conditions and the other under continuous heat stress (30⯱â¯1⯰C, 60% relative humidity). Both groups were subdivided into three dietary treatments: a methionine-deficient (MD) diet, a diet supplemented with free methionine (DL-M), and a diet supplemented with methionine dipeptide (DL-MM). Broilers raised under chronic heat stress had lower feed intake and weight gain than broilers raised under thermoneutral conditions (Pâ¯<â¯0.05). There were no differences in animal performance between methionine-supplemented diets (DL-M and DL-MM). Heat-stressed birds had significantly higher heterophil/lymphocyte (H/L) ratio than thermoneutral birds. Under heat stress, broilers fed DL-M and DL-MM diets had lower H/L ratio than birds fed the MD diet. Higher concentrations of carbonylated proteins and lower concentration of reduced glutathione were observed in broilers raised under heat stress. In comparing heat-stressed broilers, we found that birds fed the DL-M diet had lower concentrations of thiobarbituric acid-reactive substances and carbonylated proteins than those fed the MD diet (Pâ¯<â¯0.05). Higher expression of glutathione peroxidase (GPX) and glutathione synthetase (GSS) genes was observed in heat-stressed broilers (Pâ¯<â¯0.05). Under heat stress, the MD diet increased GPX expression compared with other diets. Under thermoneutral conditions, the DL-M diet resulted in the highest GSS expression. There was a negative correlation between DNA methylation and GPX and GSS expression. Our results showed that supplementation of broiler diets with free methionine or methionine dipeptide may help attenuate the effects of heat stress through enhanced activation of genes related to the glutathione antioxidant system. Methionine effects were found for gene regulation, gene expression, and post-translational processing.
Assuntos
Galinhas , Metionina , Ração Animal/análise , Animais , Galinhas/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Dipeptídeos , Temperatura Alta , Metionina/metabolismo , Estresse Oxidativo , TemperaturaRESUMO
The use of anesthetics in fish farming is essential to reduce stress during management. The present study proposes to evaluate the effect of eugenol as an anesthetic for the management of curimatã (Prochilodus nigricans). Fifty specimens were used (221.34±9.0 g; 25.8 ±1.1 cm), submitted to five treatments with concentrations of 0, 25, 50, 100 and 200 mgL−1 eugenol for 10 min. The times required to reach each anesthetic stage and the recovery of each fish were recorded. To check bloodglucose levels individual blood samples were taken from the fish before immersion and after ten minutes of anesthetic exposure. Evaluation of the anesthetic effect ongills was performed by histopathological analysis. The concentration of 50 mgL−1 was within the ideal limit of three minutes recommended for surgical anesthesia induction and did not significantly increase glucose levels when compared to the control group (35.7±19.4 mg dL−1), besides not causing gill injuries. At this concentration the fish presented controlled blood glucose levels within the basal levels, besides not taking the risk to have later problems concernig mortality, because this concentration ensures the good health of the gills and good recovery of the animals.(AU)
O uso de anestésicos em pisciculturas é indispensável para reduzir o estresse durante o manejo. O presente trabalho propôs avaliar o efeito do eugenol como anestésico para manejo do curimatã (Prochilodus nigricans). Foram utilizados 50 espécimes (221,34±9,0 g; 25,8 ±1,1 cm), submetidos a cinco tratamentos com concentrações de 0, 25, 50, 100 e 200 mg L−1 de eugenol em exposição de 10 minutos. Foram registrados os tempos necessários para atingir cada estágio anestésico e a recuperação de cada peixe. Para verificação dos níveis de glicose sanguínea, foram realizadas coletas individuais de sangue dos peixes antes da imersão e após os 10 minutos de exposição ao anestésico. A avaliação do efeito do anestésico sobre as brânquias foi realizada por meio de análises histopatológicas. A concentração de 50 mg L−1 ficou dentro do limite ideal de três minutos preconizado para indução à anestesia cirúrgica e não elevou significativamente os níveis de glicose quando comparada ao grupo controle (35,7±19,4 mg dL−1), além de não provocar lesões branquiais. Nessa concentração, os peixes apresentaram níveis de glicose sanguínea controlada, dentro dos teores basais, além de não correrem o risco de apresentarem problemas posteriores em relação à mortalidade, pois essa concentração garante a boa saúde das brânquias e uma boa recuperação dos animais.(AU)
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Animais , Eugenol/administração & dosagem , Caraciformes , Período de Recuperação da Anestesia , Aquicultura/métodos , Anestésicos GeraisRESUMO
The use of antibiotics as performance enhancers in animal feeding is declining, so Lippia gracilis Schauer essential oil (LGSEO) could be used as a potential substitute for the conventionally used growth promoters. The LGSEO contains components such as carvacrol and thymol, which kill and/or control pathogenic bacteria, increase population of beneficial organisms, act against oxidative processes and onto nutrient digestibility and absorption. The aim of this study was to investigate the action and the effects of LGSEO as a growth promoter in the diet of Japanese quail by examining their productive performance, intestinal microbiology, blood biochemical parameters, hepatic thiobarbituric acid reactive substances (TBARS) content and intestinal gene expression. A total of 252 two-day-old quail (Coturnix coturnix japonica) were assigned to 3 treatments in 7 replicates, using 12 birds per experimental unit. The treatments consisted of a basal diet, basal diet + LGSEO at 400 mg/kg of diet and basal diet + chemical antimicrobial (bacitracin methylene disalicylate) at 500 mg/kg of diet. The experimental period was 34 days. The highest feed intake (P < 0.01) was found in the group receiving the conventional antimicrobial, whereas the best feed conversion (P < 0.01) was shown by the animals receiving LGSEO. Escherichia coli growth was restricted in the quail receiving the growth promoters. Salmonella spp. growth was controlled by the treatment containing the conventional antimicrobial. There was no difference between the treatments (P > 0.05) for the concentration of aspartate aminotransferase and alanine aminotransferase enzymes in the blood or hepatic TBARS content. Birds receiving negative-control treatment exhibited a higher expression of sodium-glucose cotransporter (SGLT1), while those receiving the treatment with essential oil showed lower catalase (CAT) and glutathione peroxidase (GPX7) expressions compared to the conventional antimicrobial and control groups, respectively. Lippia gracilis Schauer essential oil is a powerful performance enhancer for Japanese quail by virtue of its abilities to improve their intestinal environment, balance the microbial population and reduce energy expenditure for oxidative processes.
Assuntos
Coturnix , Lippia , Óleos Voláteis , Ração Animal/análise , Animais , Coturnix/crescimento & desenvolvimento , Dieta , Suplementos Nutricionais , Óleos Voláteis/farmacologiaRESUMO
Caprine arthritis encephalitis (CAE) is a chronic disease caused by a retrovirus from the Lentivirus genus. No effective vaccines or treatments exist, and therefore genetic selection for CAE resistance might be a feasible alternative. To our best knowledge, no other studies have investigated the genetic architecture of CAE resistance in dairy goats. In this context, this study was designed to estimate genetic parameters for CAE infection in Alpine and Saanen goats using a Bayesian threshold model. A total of 542 adult goats (and >3-generation pedigree), which were group-housed in a population with high CAE prevalence, were tested based on a serological infection assessment test (negative = 1 or positive = 2) and used for this study. Genetic parameters were estimated using the BLUPF90 family programs. There was considerable genetic variability for CAE resistance, and pedigree-based heritability was significantly different from zero (0.026 < heritability < 0.128). Our findings indicate that the prevalence of CAE in goat herds can be reduced or eliminated through direct genetic selection for CAE resistance in addition to proper management strategies.
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Vírus da Artrite-Encefalite Caprina , Predisposição Genética para Doença , Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Animais , Teorema de Bayes , Doenças das Cabras/epidemiologia , Cabras , Infecções por Lentivirus/genética , Infecções por Lentivirus/virologiaRESUMO
BACKGROUND: Actinic cheilitis (AC) is a potentially malignant disorder of the lip, characterized by epithelial and connective tissue alterations caused by chronic exposure to ultraviolet radiation. In the past decades, diverse studies have been conducted in lip carcinogenesis and many biomarkers have been identified in lip lesions, yet there is no scientific evidence that determines its usefulness in the clinical setting or in histopathological routine. Therefore, we conducted the first systematic review in this field to summarize the results of published studies on immunohistochemical biomarkers in lip carcinogenesis, to evaluate if there is a marker than can distinguish the different histological grades of AC. MATERIAL AND METHODS: Retrospective studies that investigated immunohistochemical biomarkers in AC defined on standardised histological assessment were gathered from five databases and evaluated. Each study was qualitatively evaluated using the Critical Appraisal Tools from SUMARI. RESULTS: The proliferation marker Ki-67 was the most studied biomarker and we observed, through meta-analysis, that it was differently expressed between AC and lip cancer, but not in AC subgroups. Most articles had a high risk of bias. CONCLUSIONS: In summary, the literature lacks quality follow up studies in actinic cheilitis. Multi-centre cohort studies, with patients stratified by treatment type and the use of image analysis software, could be the solution to further address the issues of investigating potentially malignant lesions and help change clinical practice, in terms of individualizing patients' treatment and prognosis prediction.
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Queilite , Neoplasias Labiais , Biomarcadores , Humanos , Estudos Retrospectivos , Raios UltravioletaRESUMO
Coherent generation of indistinguishable single photons is crucial for many quantum communication and processing protocols. Solid-state realizations of two-level atomic transitions or three-level spin-Λ systems offer significant advantages over their atomic counterparts for this purpose, albeit decoherence can arise due to environmental couplings. One popular approach to mitigate dephasing is to operate in the weak-excitation limit, where the excited-state population is minimal and coherently scattered photons dominate over incoherent emission. Here we probe the coherence of photons produced using two-level and spin-Λ solid-state systems. We observe that the coupling of the atomiclike transitions to the vibronic transitions of the crystal lattice is independent of the driving strength, even for detuned excitation using the spin-Λ configuration. We apply a polaron master equation to capture the non-Markovian dynamics of the vibrational manifolds. These results provide insight into the fundamental limitations to photon coherence from solid-state quantum emitters.
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OBJECTIVES: To evaluate the effect of combining in-office with at-home bleaching procedures in terms of the time required to obtain satisfactory tooth color, final color changes, and tooth sensitivity (TS) reported by patients. METHODS AND MATERIALS: Twenty-six patients enrolled in this study used 10% carbamide peroxide in a bleaching tray for 1 h/d until satisfactory tooth color was obtained. One-half of the participants underwent a preliminary session of in-office tooth bleaching with 35% hydrogen peroxide for 45 minutes. The time in days for the patients to obtain satisfactory tooth color by at-home bleaching procedures was recorded. The color change of the maxillary canines was assessed using the Vita Bleachedguide 3D Master scale and a spectrophotometer at 1 week and after the end of bleaching procedures. Participants' satisfaction with their smile was recorded using a visual analog scale, and TS was determined throughout the entire treatment. Data were analyzed by t-test, Mann-Whitney test, or Fisher exact test (α=0.05). RESULTS: The combined protocol reduced (by an average of 3.7 days) the time required to obtain satisfactory tooth color but increased the risk and level of TS. No difference in the final tooth color change (around 5.0 shade guide units; ΔE=11.6-14.9), or the level of patients' satisfaction with their smile, was observed. CONCLUSIONS: A preliminary session of in-office bleaching reduced the time necessary to obtain satisfactory tooth color with at-home bleaching but increased the risk and level of TS.
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Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Cor , Humanos , Peróxido de Hidrogênio , Resultado do TratamentoRESUMO
BACKGROUND: Ameloblastoma (AMB), odontogenic keratocyst (OKC) and adenomatoid odontogenic tumor (AOT) are epithelial odontogenic lesions with diverse biologic profiles. Defects in regulation of apoptosis and cell cycle may be involved in the development and progression of those lesions, therefore we aimed to investigate the expression of Bcl-2, Bax and p53 to better understand the possible role of these proteins in AMBs, OKCs and AOTs. MATERIAL AND METHODS: The studied sample consisted of 20 AMBs, 20 OKCs and 20 AOTs. Immunohistochemistry technique was performed for the antibodies p53, Bcl-2 and Bax. Immunoreactivity was observed in the epithelial component and positive cells were counted in five fields (100x magnification). Statistical analysis was performed with Kruskal-Wallis and Spearman tests (p <0.05). RESULTS: All lesions exhibited staining for the three studied proteins. There was no statistically significant associations between the expression of proteins and the lesions, however we identified a positive correlation between the expression of p53 and Bcl-2 (r = 0.200) and a negative correlation between p53 and Bax expressions (r = -0.100). In addition, p53 and Bax were similarly expressed between AMBs and OKCs. Bcl-2 was similarly expressed in AMBs and AOTs. CONCLUSIONS: Apoptosis regulatory proteins, as well as cell cycle proteins, are differently expressed in epithelial odontogenic lesions and their expression is possibly related to the biological behavior of AMB, OKC and AOT.
Assuntos
Ameloblastoma/metabolismo , Ameloblastoma/patologia , Apoptose , Ciclo Celular , Neoplasias Maxilomandibulares/metabolismo , Neoplasias Maxilomandibulares/patologia , Cistos Odontogênicos/metabolismo , Cistos Odontogênicos/patologia , Proteína Supressora de Tumor p53/biossíntese , Proteína X Associada a bcl-2/biossíntese , Proteína bcl-X/biossíntese , Humanos , Imuno-Histoquímica , OdontogêneseRESUMO
A semiconductor quantum dot can generate highly coherent and indistinguishable single photons. However, intrinsic semiconductor dephasing mechanisms can reduce the visibility of two-photon interference. For an electron in a quantum dot, a fundamental dephasing process is the hyperfine interaction with the nuclear spin bath. Here, we directly probe the consequence of the fluctuating nuclear spins on the elastic and inelastic scattered photon spectra from a resident electron in a single dot. We find the in-plane component of the nuclear Overhauser field leads to detuned Raman scattered photons, broadened over experimental time scales by field fluctuations, which are distinguishable from both the elastic and incoherent components of the resonance fluorescence. This significantly reduces two-photon interference visibility. However, we demonstrate successful screening of the nuclear spin noise, which enables the generation of coherent single photons that exhibit high visibility two-photon interference.
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There are very few reports on the self-assembly of peptides derived from proteins of agro industrial byproducts origin. Although it has been claimed that purity is a determining factor in peptide self-assembly, whether proteins extracted using water along with other components also form self-assembled structures is not known. The results of this work prove that albumins from wheat bran, a byproduct obtained from the milling industry, can form tubular nanostructures during their hydrolysis with the V8 protease in the presence of Ca(2+). Electron microscopy of the hydrolysate revealed that under specific conditions, long filaments are formed, which are nanotubes of several microns in length, with inner and outer diameters of 100 and 200 nm, respectively. The infrared analysis of the hydrolysate identified (-)OOC-Ca(2+) interactions and changes in beta sheet content in response to variations in protein/V8/Ca(2+) molar ratios. A model that explains the probable mechanism of the observed self-assembly is discussed.
Assuntos
Albuminas/química , Cálcio/química , Fibras na Dieta/análise , Nanoestruturas/química , Serina Endopeptidases/química , Nanotubos/química , Peptídeos/química , ProteóliseRESUMO
OBJECTIVE: It was recently demonstrated that using a tray over a bleaching agent reduces its pulpal chamber penetration, which can reduce tooth sensitivity. This study evaluated the effect of the sealed technique on the presence and level of sensitivity reported by patients during and after the bleaching procedure performed in office. METHODS: Forty-six patients underwent a bleaching procedure with 35% hydrogen peroxide used in a single application of 45 minutes for two sessions with an interval of seven days. A customized tray was maintained over the bleaching agent during the entire procedure in half of the patients. The sensitivity level was evaluated during and immediately after the bleaching using verbal and visual analogue scales. The shade alteration was evaluated with a bleach guide scale. The peak sensitivity after 24 hours and the presence/level at 24 hours were also evaluated using a verbal rating scale. Relative risks were calculated for all time assessments. Data on the sensitivity level for both scales were subjected to Friedman and Mann-Whitney tests (α=0.05). Data on the shades were analyzed by two-way repeated-measures analysis of variance and Tukey's test (α=0.05). RESULTS: The use of a customized tray increased the relative risks to the tooth measured 24 hours after each bleaching session. The sealed technique also increased the level of tooth sensitivity only at 24 hours after the first session. No difference was observed between the bleaching techniques regarding the shade evaluation. CONCLUSION: Using a tray over the bleaching agent can increase the level and risk of tooth sensitivity for the first 24 hours after in-office bleaching.
Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Dente , Humanos , Peróxido de HidrogênioRESUMO
Objective: To investigate the effects of cryotherapy on markers of muscle damage, as well as the perception of muscle soreness caused by eccentric exercise after downhill running. Methods: Ten participants (age = 26 ± 5 year, height = 173 ± 8 cm and body mass = 70 ± 4 kg) performed two running trials on a treadmill tilted 6.6%, separated by one-week period. Cryotherapy (∼15 ◦C for 30 minutes) was conducted after one of the trials of exercise. Blood samples were analyzed for markers of muscle damage (creatine kinase - CK; lactate dehydrogenase - LDH; calcium - [Ca2+]). Perception of muscle soreness was quantified using an analogical scale of pain. Data were collected before, 24 and 48 h after the trials with and without the use of cryotherapy. Results: Cryotherapy significantly reduced muscle soreness and was able to reestablish homeostasis in CK, LDH and [Ca2+]. Conclusion: Use of cryotherapy after exercise with eccentric contractions was effective to reestablish the level of biochemical markers of muscle damage and reduce muscle soreness and pain perception in subjects submitted to downhill running (AU)
Objetivo: Investigar los efectos de la crioterapia en los marcadores de daño muscular, así como la percepción de mialgia causada por ejercicio excéntrico tras carrera en bajada. Método: Diez participantes (edad = 26,0 ± 5,0 años, altura = 173,0 ± 8,0 cm y masa corporal = 70,5 ± 4,0 kg) realizaron dos ensayos de carrera en tapiz rodante con una inclinación de 6.6%, separados por un periodo de una semana. Se llevó a cabo una sesión de crioterapia (∼15 ◦C,) tras cada uno de los ensayos. Se analizaron muestras de sangre para determinar los marcadores de daño muscular (creatín kinasaCK; deshidrogenasa lácticaDHL; calcio - [Ca2+]). La percepción de dolor muscular fue cuantificada usando una escala analógica de dolor. Los datos se tomaron antes, 24 h y 48 h después de los ensayos con y sin el uso de crioterapia. Resultados: La crioterapia disminuyó significantemente el dolor muscular y fue capaz de reestablecer la homeostasis en CK, DHL y [Ca2+]. Conclusión: El uso de crioterapia tras ejercicio con contracciones excéntricas fue efectivo para reestablecer el nivel de los marcadores bioquímicos de daño muscular y reducir la mialgia y la percepción de dolor en sujetos sometidos a carrera en bajada (AU)
Introdução: O dano muscular é frequentemente observado em indivíduos envolvidos em atividades físicas que envolvam contrações excêntricas. Nestas situações, a crioterapia é utilizada para reduzir o dano muscular e a sensação de dor. No entanto, poucos estudos investigaram o efeito da imersão em agua gelada em marcadores de dano muscular, bem como a percepção de dor após exercício excêntrico. Método: Dez homens (26,0 ± 5,0 anos de idade, 173,0 ± 8,0 cm de estatura, 70,5 ± 4,0 kg de massa corporal). Os voluntários completaram dois corridas (teste e controle) separadas por sete dias, em um percurso declinado (-6,6%) em esteira. Em uma das tentativas realizou-se imersão em água gelada (~15 oC, 30 minutos). O dano muscular foi estimado mediante os níveis sanguíneos de (creatina quinase-CK; lactato desidrogenase-LDH e cálcio-[Ca2+]). A percepção de dor muscular foi estimada usando uma escala analógica. Todas as medidas foram realizadas antes, 24 e 48 horas pós-exercício. Resultados: A imersão em agua gelada diminuiu significativamente a dor muscular e auxiliou no reestabelecimento da homeostase da CH, LDH e Ca2+. Conclusão: A imersão em agua gelada após exercício excêntrico foi efetiva em reestabelecer os níveis bioquímicos de marcadores musculares e diminuiu a percepcao de dor (AU)
Assuntos
Humanos , Crioterapia , Exercício Físico/fisiologia , Mialgia/terapia , Corrida/fisiologia , Mediadores da Inflamação/análise , Inflamação/fisiopatologia , Esforço Físico/fisiologiaRESUMO
Laccases are environmentally friendly alternatives in many important applications such as in bioremediation, biopulping, textile, and the food industry. They have wide substrate specificity, can oxidize a broad range of compounds, and show potential for use in various industrial processes. Therefore, developing methods to increase laccase production is important. In the current study, we aimed to identify optimum conditions for inducing laccase production in the basidiomycete Lentinus crinitus cultivated under varying nitrogen concentrations and in the presence of potential inducers of laccase production, including copper and phenolic compounds. Peak enzymatic activity (11,977 U/L) occurred at higher nitrogen concentrations (2.8 g/L nitrogen). Regardless of the nitrogen concentration, addition of copper increased the laccase activity and decreased mycelial growth, with maximum laccase activity (14,320 U/L) observed at the highest nitrogen concentration combined with 150 mM CuSO4. In addition, ethanol (0.5 or 1.0 mM) and guaiacol (1.5 mM) increased laccase production to 15,000, 14,800, and 14,850 U/L, respectively. Our findings highlighted the optimum conditions for producing L. crinitusderived laccase as potential alternatives to the conventional production and application of the enzyme.
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Lacase/biossíntese , Lentinula/metabolismo , Cobre/química , Meios de Cultura/química , Lentinula/crescimento & desenvolvimento , Nitrogênio/químicaRESUMO
The effects of the addition of glycerol (GLY) on the physicochemical and morphological properties of poly(vinyl alcohol) (PVA)-agar films were reported. PVA-agar films were prepared by solution cast method, and the addition of GLY in PVA-agar films altered the optical properties, resulting in a decrease in opacity values and in the color difference (ΔE) of the films. Structural characterization using Fourier transformation infrared (FTIR) spectroscopy and X-ray diffraction (XRD) indicated that the presence of GLY altered the intensity of the bands (from 1200 to 800cm(-1)) and crystallinity. The characterization of the thermal properties indicated that an increase in the agar content produces a decrease in the melting temperature and augments the heat of fusion. Similar tendencies were observed in plasticized films, but at different magnification. The formulation that demonstrated the lowest mechanical properties contained 25wt.% agar, whereas the formulation that contained 75wt.% agar demonstrated a significant improvement. The water vapor transmission rate (WVTR) and surface morphology analysis demonstrated that the structure of PVA-agar films is reorganized upon GLY addition. The physicochemical properties of PVA-agar films using GLY as a plasticizer provide information for the application of this formulation as packaging material for specific food applications.
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Ágar/química , Fenômenos Químicos , Plastificantes/química , Álcool de Polivinil/química , Embalagem de Alimentos , Fenômenos Mecânicos , Fenômenos Ópticos , Solubilidade , Temperatura , Volatilização , Água/químicaRESUMO
In previous studies, we observed dystrophic alterations in muscle of 48-day-old sea bass fed imbalanced docosahexaenoic acid (DHA) and vitamin E diets. To understand the whole pathological process associated with oxidative stress, a histological study was performed by feeding 14-day-old sea bass larvae with microdiets containing different ratios of DHA/vitamin E (1/150, 5/150 and 5/300) for a period of 21 days. Larvae fed diet 1/150 showed no lesions in contrast to larvae fed diets 5/150 and 5/300 where the highest incidence of muscle lesions and thiobarbituric acid reactive substances (TBARS) content was observed. Semithin sections revealed focal lesions consisting of degenerated fibres with hypercontracted myofilaments and extensive sarcoplasm vacuolization affecting both red and white muscle. Ultrathin sections of degenerating muscle fibres showed diffuse dilatation of sarcoplasmic reticulum, disorganized myofilaments and autophagic vacuoles containing myelin figures and dense bodies. Additionally, some macrophages were observed among injured fibres as numerous satellite cells. Results from the study agree with those obtained from previous work, proving the pathological potential of free radicals in sea bass larvae musculature. Moreover, high vitamin E inclusion could not completely protect cell membranes from free radicals action.
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Bass/fisiologia , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Vitamina E/administração & dosagem , Animais , Dieta/veterinária , Larva/efeitos dos fármacos , Larva/fisiologia , Microscopia Eletrônica de Transmissão/veterinária , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Espanha , Espectrofotometria/veterináriaRESUMO
The aim of the present study was to analyze the electromyographic (EMG) signals of the rectus femoris (RF), vastus lateralis (VL), tibialis anterior (TA) and soleus (SO) muscles in young healthy adults with and without the use of an experimental ankle-foot-orthosis (AFO) designed for patients with hemiparesis. Twenty-eight individuals with an average age of 22 +/- 3.63 years participated in the study. An electromyograph, surface electrodes and two force plates were used. There was a non-significant increase in the TA activity with the use of the AFO (6.04 +/- 2.81) when compared to non-use (5.91 +/- 2.49) (p > 0.5); the same was true for the other muscles evaluated. There was a positive correlation (r = 0.37) between TA and SO activity (p < 0.05). The results demonstrate that the AFO did not affect the gait pattern of healthy young adults.
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Pé/fisiologia , Marcha/fisiologia , Aparelhos Ortopédicos , Paresia/fisiopatologia , Adolescente , Adulto , Eletromiografia , Feminino , Humanos , Masculino , Paresia/reabilitação , Estatísticas não ParamétricasRESUMO
Objetivo : estabelecer diretrizes para as investigações sobre a transdisciplinaridade na Medicina Periodontal. Métodos: representantes das diferentes especialidades que estudam e pesquisam diversoa aspectos da Medicina Periodontal participaram do II Seminário de Periodontia em Saúde Coletiva - Uma Visão Transdisciplinar na Medicina Periodontal (Feira de Santana-Bahia, 2005) e prepararam este consenso, no qual estabeleceram as diretrizes para as investigações sobre a transdisciplinaridade na Medicina Periodontal, particularmente na questão da possível associação entre a doença periodontal e a prematuridade e baixo peso ao nascer. Resultados: Este consenso foi produzido após a apresentação de cada questão e extensa discussão pelos participantes do evento