Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Clin Nutr ; 43(1): 95-110, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016244

RESUMO

AIMS: This scoping review aimed to identify, explore, and map the objectives, methodological aspects, and results of studies that used ultrasound (US) to assess skeletal muscle (SM) in critically ill patients. METHODS: A scoping review was conducted according to the Joanna Briggs Institute's methodology. All studies that evaluated SM parameters from the US in patients admitted to the intensive care unit (ICU) were considered eligible. We categorized muscle thickness and cross-sectional area as parameters for assessing SM quantity, while echogenicity, fascicle length, and pennation angle analysis were used to evaluate muscle "quality" (composition/architecture). A literature search was conducted using four databases for articles published until December 2022. Independent reviewers selected the studies and extracted data. Descriptive statistics were calculated to present the results. RESULTS: A total of 107 studies were included, the majority of which were prospective cohort studies (59.8 %) conducted in general ICUs (49.5 %). The most frequent objective of the studies was to evaluate SM quantity depletion during the ICU stay (25.2 %), followed by determining whether a specific intervention would modify SM (21.5 %). Most studies performed serial SM evaluations (76.1 %). The rectus femoris muscle thickness was evaluated in most studies (67.9 %), followed by the rectus femoris cross-sectional area (54.3 %) and the vastus intermedius muscle thickness (40.2 %). The studies demonstrated the feasibility and reproducibility of US for SM evaluation, especially related to quantitative parameters. Most studies (70.3 %) reported significant SM quantity depletion during hospitalization. However, the accuracy of the US in measuring SM varied across the studies. CONCLUSIONS: The lack of detailed description and standardization in the protocols adopted by the studies included in this scoping review precludes the translation of the evidence related to US for SM assessment into clinical practice.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Humanos , Estudos Prospectivos , Reprodutibilidade dos Testes , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia
3.
ACS Appl Mater Interfaces ; 15(40): 46790-46802, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37774150

RESUMO

Aminopolymer-based sorbents are preferred materials for extraction of CO2 from ambient air [direct air capture (DAC) of CO2] owing to their high CO2 adsorption capacity and selectivity at ultra-dilute conditions. While those adsorptive properties are important, the stability of a sorbent is a key element in developing high-performing, cost-effective, and long-lasting sorbents that can be deployed at scale. Along with process upsets, environmental components such as CO2, O2, and H2O may contribute to long-term sorbent instability. As such, unraveling the complex effects of such atmospheric components on the sorbent lifetime as they appear in the environment is a critical step to understanding sorbent deactivation mechanisms and designing more effective sorbents and processes. Here, a poly(ethylenimine) (PEI)/Al2O3 sorbent is assessed over continuous and cyclic dry and humid conditions to determine the effect of the copresence of CO2 and O2 on stability at an intermediate temperature of 70 °C. Thermogravimetric and elemental analyses in combination with in situ horizontal attenuated total reflection infrared (HATR-IR) spectroscopy are performed to measure the extent of deactivation, elemental content, and molecular level changes in the sorbent due to deactivation. The thermal/thermogravimetric analysis results reveal that incorporating CO2 with O2 accelerates sorbent deactivation using these sorbents in dry and humid conditions compared to that using CO2-free air in similar conditions. The in situ HATR-IR spectroscopy results of PEI/Al2O3 sorbent deactivation under a CO2-air environment show the formation of primary amine species in higher quantity (compared to that in conditions without O2 or CO2), which arises due to the C-N bond cleavage at secondary amines due to oxidative degradation. We hypothesize that the formation of bound CO2 species such as carbamic acids catalyzes C-N cleavage reactions in the oxidative degradation pathway by shuttling protons, resulting in a low activation energy barrier for degradation, as probed by metadynamics simulations. In the cyclic experiment after 30 cycles, results show a gradual loss in stability (dry: 29%, humid: 52%) under CO2-containing air (0.04% CO2/21% O2 balance N2). However, the loss in capacity during cyclic studies is significantly less than that during continuous deactivation, as expected.

4.
Nutrients ; 15(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37432223

RESUMO

(1) Background: Adolescence is characterized by changes in eating habits, with increased consumption of ultra-processed foods and reduced intake of unprocessed or minimally processed foods, which can affect body image satisfaction. Thus, this study aims to verify the association of food consumption according to the degree of processing with body image (dis)satisfaction in adolescents from the 1997/1998 birth cohort of São Luís, Maranhão. (2) Methods: A cross-sectional study was conducted with 2515 adolescents aged between 18 and 19. Food consumption was stratified based on the NOVA classification in culinary preparations, processed foods, and ultra-processed foods, categorized into tertiles. Body image (dis)satisfaction was evaluated based on the Stunkard Body Scale and was classified as satisfaction, dissatisfaction with thinness, and dissatisfaction with excess weight. Multinomial logistic regression was used for associations. (3) Results: Among the adolescents, 77% considered themselves dissatisfied with their body image, with 42.8% dissatisfied with being thin and 34.2% dissatisfied with excess weight. However, food consumption, according to the degree of processing, was not associated with body image (dis)satisfaction. (4) Conclusion: This work highlighted the prevalence of body image dissatisfaction among adolescents but found no association between body (dis)satisfaction and food consumption according to the degree of processing.


Assuntos
Insatisfação Corporal , Imagem Corporal , Adolescente , Humanos , Adulto Jovem , Adulto , Estudos Transversais , Coorte de Nascimento , Aumento de Peso , Satisfação Pessoal
5.
Angew Chem Int Ed Engl ; 62(24): e202302887, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37067387

RESUMO

Direct air capture (DAC) processes for extraction of CO2 from ambient air are unique among chemical processes in that they operate outdoors with minimal feed pretreatments. Here, the impact of humidity on the oxidative degradation of a prototypical solid supported amine sorbent, poly(ethylenimine) (PEI) supported on Al2 O3 , is explored in detail. By combining CO2 adsorption measurements, oxidative degradation rates, elemental analyses, solid-state NMR and in situ IR spectroscopic analysis in conjunction with 18 O labeling of water, a comprehensive picture of sorbent oxidation is achieved under accelerated conditions. We demonstrated that the presence of water vapor can play an important role in accelerating the degradation reactions. From the study we inferred the identity and kinetics of formation of the major oxidative products, and the role(s) of humidity. Our data are consistent with a radical mediated autooxidative degradation mechanism.

6.
Nutrients ; 14(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36501210

RESUMO

(1) Background: During adolescence, there are significant changes in food consumption, such as reducing the consumption of in natura or minimally processed foods and increasing the consumption of ultra-processed foods. Thus, eating habits can influence sleep duration and, consequently, affect the quality of life of young people. This study thus aims to estimate the association of consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations in adolescents. (2) Methods: This is a cross-sectional study including 964 adolescents (18 to 19 years old) from the 1997 to 1998 birth cohort in São Luís, Maranhão. Food consumption was assessed using the food frequency questionnaire (FFQ) and stratified based on the NOVA classification. Sleep duration was verified using accelerometry in hours. The analysis of the association between the consumption of in natura or minimally processed, processedand ultra-processed foods with sleep durations in adolescents used crude and adjusted linear regression (by gender, age, skin color, education, economic class, work, consumption of alcohol, smoking, screen time, physical activity, use of illicit drugs, anxiety, depressive symptoms, and lean and fat mass). A directed acyclic graph (DAG) was used to determine the minimum set of adjustment factors. (3) Results: Of the 964 individuals evaluated, 52.0% were female. The mean sleep duration was 6 h (± 0.95). In the crude and adjusted analyses, no association was observed between food consumption according to the degree of processing and adolescent sleep durations. (4) Conclusion: There was no association between the consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations.


Assuntos
Fast Foods , Duração do Sono , Adolescente , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Estudos Transversais , Qualidade de Vida , Brasil , Ingestão de Alimentos , Manipulação de Alimentos , Ingestão de Energia , Dieta
7.
Mol Biol Rep ; 49(10): 9509-9520, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35980532

RESUMO

BACKGROUND: About 5-10% of breast cancer cases are related to genetic and hereditary factors. The application of Next Generation Sequencing (NGS) in oncology has allowed the identification of genetic variants present in several genes related to the increased risk of breast cancer. This study aimed to determine the frequency of germline genetic variants in patients with a family and/or personal history of breast cancer. METHODS: An analysis of positive reports from NGS panels was carried out in female individuals with a personal and/or family history of breast cancer, present in the database of a private laboratory in Brazil. RESULTS: From about 2000 reports, 183 individuals presented 219 different germline genetic variants. The genes with the highest number of variants were BRCA2 (16.0%), ATM (15.0%) and BRCA1 (12.8%). Among the variants found, 78 were either pathogenic or probably pathogenic, accounting for 35% of all variants discovered. The gene with the highest proportion of pathogenic/probably pathogenic variants was TP53 (80%) and the most frequent pathogenic variant was also reported in this gene (c.1010G > A p.(Arg337His)). Furthermore, the study obtained a high proportion of variants of uncertain significance (VUS) (65%) and approximately 32% of the variants found were in genes of moderate penetrance. CONCLUSIONS: Our results could improve the risk estimation and clinical follow-up of Brazilian patients with a history of breast cancer.


Assuntos
Neoplasias da Mama , Proteína BRCA1/genética , Brasil/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Genes BRCA2 , Predisposição Genética para Doença , Células Germinativas , Mutação em Linhagem Germinativa/genética , Humanos
8.
Animals (Basel) ; 11(12)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34944213

RESUMO

The objectives of this study were: (1) to evaluate feed efficiency indexes and their relationships with body measurements and blood and ruminal metabolites in the pre-weaning period; (2) to determine if such measurements can be used as feed-efficiency markers during the pre-weaning period. Holstein-Gyr heifer calves (n = 36), enrolled between 4 and 12 weeks of age, were classified into two residual feed intake (RFI) and residual body weight gain (RG) groups: high efficiency (HE; RFI, n = 10; and RG, n = 9), and low efficiency (LE; RFI, n = 10; and RG, n = 8). Calves were fed whole milk (6 L/day) and solid feed ad libitum. Body developments were measured weekly and feed intake (milk and solid feed) daily during the whole period. Blood samples were collected at 12 weeks of age and analyzed for glucose, insulin and ß-hydroxybutyrate (BHB). Samples of ruminal content were collected on the same day and analyzed for pH, NH3-N, and volatile fatty acids (VFA). Among the growth characteristics, only the initial hip width differed between the RFI groups, and withers height differed between the RG groups. Concentration of BHB was greater and glucose: insulin ratios tended to be greater in LE-RG animals. Butyric acid proportions were similar among RFI groups, but tended to be greater for HE-RG than for LE-RG. Overall, correlation coefficients between RFI or RG and blood, rumen, or morphometric markers were low. Thus, it is unlikely that measurements of metabolic indicators, per se, will be useful in the early identification of more efficient animals. Understanding the underlying physiological basis for improved feed efficiency in dairy heifers requires further investigation.

9.
Femina ; 49(9): 530-536, 2021. ilus, tab
Artigo em Português | LILACS | ID: biblio-1342322

RESUMO

A síndrome dos ovários policísticos (SOP) é uma condição endócrina frequente em mulheres em idade reprodutiva. O quadro clínico é manifesto por anovulação crônica hiperandrogênica, acompanhada muitas vezes de infertilidade; além disso, essa condição está associada ao aumento de distúrbios do metabolismo glicídico e a diversos outros riscos em longo prazo. Uma vez gestante, a mulher portadora de SOP apresenta risco aumentado em 2,8 vezes para o diabetes gestacional, em 2,0 a 4,0 vezes para o desenvolvimento de síndromes hipertensivas da gestação e em 2,3 vezes para internação em UTI neonatal. Independentemente do excesso de peso, que é comumente associado à síndrome e que certamente potencializa o risco de complicações, a SOP por si só promove alterações que cursam com a elevação dessas complicações. Esta é uma revisão narrativa sobre as potenciais complicações gestacionais relacionadas à SOP e compila a literatura mais atual sobre o tema.(AU)


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Síndrome do Ovário Policístico/complicações , Complicações na Gravidez , Gravidez de Alto Risco , Aborto Espontâneo/etiologia , Fatores de Risco , Bases de Dados Bibliográficas , Diabetes Gestacional/etiologia , Hipertensão Induzida pela Gravidez/etiologia , Trabalho de Parto Prematuro/fisiopatologia
10.
Int. j. cardiovasc. sci. (Impr.) ; 33(6): 629-634, Nov.-Dec. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1143119

RESUMO

Abstract Background Malnutrition can affect the clinical course of hospitalized patients, increasing hospital stay, infections, mortality, and hospital costs. Among heart disease patients, the malnutrition prevalence ranges from 25 to 51.9%. Objective To assess the prevalence of malnutrition and its association with clinical complications in cardiac patients admitted to a cardiology hospital. Method Retrospective cohort study with patients evaluated within 48 hours of admission to the ward of a referral center for cardiology in Porto Alegre, Brazil. Patients were aged 18 years or older. Malnutrition was assessed by Subjective Global Assessment. Length of hospital stay, transfer to the intensive care unit (ICU), hospital discharge and in-hospital death were collected from medical records. Statistical analysis was performed using the SPSS 22.0 program. Comparisons between groups with and without malnutrition were made by unpaired Student's t-test and chi-square test with adjusted residuals, and multivariate Poisson regression used for analysis of outcomes. The significance level considered was 5%. Results We evaluated 130 patients aged 63 ± 13 years, 63% were male, and the most frequent cause of hospitalization was angina (25%). The prevalence of malnutrition was 27% and, after statistical adjustment for age, malnutrition was positively associated with ICU transfer and length of hospital stay longer than seven days. Conclusion The prevalence of malnutrition found in this sample was 27% and this nutritional diagnosis was positively associated with ICU transfer and length of hospital stay longer than seven days. (Int J Cardiovasc Sci. 2020; [online].ahead print, PP.0-0)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Doenças Cardiovasculares/complicações , Desnutrição/complicações , Doenças Cardiovasculares/mortalidade , Estudos Retrospectivos , Desnutrição/epidemiologia , Tempo de Internação
11.
Heliyon ; 6(7): e04446, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32695917

RESUMO

The Artisan Minas Cheese (AMC) is the oldest and most traditional Brazilian cheese, it is produced in several regions of the state of Minas Gerais, such as the Serro region. The most striking features of the AMC-Serro are the use of raw milk and natural bacteria from the whey, popularly known as pingo, as well as the use of the rind washing process. The aim of the present study was to evaluate the proteolysis of the AMC-Serro from three different producers, during 60 days of maturation, and to relate the proteolysis to the producing farms, the production season and the rind washing during ripening. For this purpose, TRICINE-SDS-PAGE, proteolysis extension and depth indices, moisture, and texture (firmness) were evaluated. It was concluded that the temperature and moisture of the cheeses, that were determined by the location of the ripening room, the production season and the rind washing, were the most important factors. The degree of proteolysis also had an impact on the water loss during ripening, with effect on cheese safety. The results obtained in this study may be used to better understand the transformations during ripening of AMC-Serro and help the small traditional farmers to improve their product's quality and stability.

12.
Annu Rev Chem Biomol Eng ; 10: 85-104, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31173521

RESUMO

Dwindling fossil fuel resources and substantial release of CO2 from their processing have increased the appeal to use biomass as a sustainable platform for synthesis of chemicals and fuels. Steps toward this will require selective upgrading of biomass to suitable intermediates. Traditionally, biomass upgrading has involved thermochemical processes that require excessive amounts of petrochemical-derived H2 and suffer from poor product selectivity. Electrochemical routes have emerged as promising alternatives because of (a) the replacement of petrochemical-derived H2 by protons generated in situ, (b) mild operating temperatures and pressures, and (c) the use of electrode potential to tune reaction rates and product selectivity. In this review, we highlight the advances in the electrocatalytic hydrogenation and oxidation of biomass-derived platform molecules. The effects of important reaction parameters on electrochemical efficiency and catalytic activity/selectivity are thoroughly discussed. We conclude by summarizing current challenges and discussing future research directions.


Assuntos
Biomassa , Técnicas Eletroquímicas/métodos , Oxigênio/química , Catálise , Hidrogenação , Oxirredução , Prótons
13.
J Transl Med ; 16(1): 240, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30165858

RESUMO

BACKGROUND: Individuals with arterial hypertension often have an autonomic nervous system (ANS) imbalance with predominance of sympathetic ANS. This predominance can lead to injury of several organs affecting its functioning. There is evidence that performing high intensity resistance training (RT) with heavier loads and a lower number of repetitions results in lower cardiovascular stress when compared with lighter loads and a higher number of repetitions. However, the effects of different protocols of RT in autonomic modulation are not known. Therefore, the aim of the study was to analyze and compare the effects of different protocols of high intensity of effort RT on autonomic cardiac modulation of hypertensive women. METHODS: A randomized crossover design clinical trial was conducted with 15 postmenopausal hypertensive women who underwent a control session and two high intensity RT protocols involving 6 and 15 repetition maximum (RM). Heart rate variability (HRV), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and double product (DP) were collected pre, immediately post, 1 h post, and 24 h post each protocol. Repeated-measures ANOVA were used. RESULTS: SBP was higher for 6RM than control immediately after session (p < 0.05). There were no differences for DBP among protocols (p ≥ 0.05). HR was higher for 15RM than 6RM and control immediately after and 1 h after session (p ≤ 0.05). DP values for 15RM were significantly higher than 6RM and control immediately after the session and remained higher than control 1 h after session (p ≤ 0.05). The indices that compose HRV (rMSSD) were lower after 15RM than 6RM and control (p ≥ 0.05). The parameters of parasympathetic activity (HF) were decreased and sympathetic (LF) activity was increased for 15RM when compared to the 6RM and control session immediately after the exercise session (p ≤ 0.05). CONCLUSION: Performing high intensity RT with lower loads and a higher number of repetitions seems to promote acute increases in sympathetic ANS activity, which may be related to cardiovascular stress. On the other hand, heavier load and lower repetition RT did not significantly impact upon autonomic modulation when compared to a control session.


Assuntos
Sistema Nervoso Autônomo , Doenças Cardiovasculares/terapia , Exercício Físico/fisiologia , Hipertensão/terapia , Pós-Menopausa , Treinamento de Força , Idoso , Antropometria , Pressão Sanguínea , Sistema Cardiovascular , Estudos Cross-Over , Diástole , Feminino , Coração/fisiologia , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Sístole
14.
J Am Chem Soc ; 140(26): 8128-8137, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29847727

RESUMO

Oxygen electrocatalysis plays a critical role in the efficiency of important energy conversion and storage systems. While many efforts have focused on designing efficient electrocatalysts for these processes, optimal catalysts that are inexpensive, active, selective, and stable are still being searched. Nonstoichiometric, mixed-metal oxides present a promising group of electrocatalysts for these processes due to the versatility of the surface composition and fast oxygen conducting properties. Herein, we demonstrate, using a combination of theoretical and experimental studies, the ability to develop design principles that can be used to engineer oxygen electrocatalysis activity of layered, mixed ionic-electronic conducting Ruddlesden-Popper (R-P) oxides. We show that a density function theory (DFT) derived descriptor, O2 binding energy on a surface oxygen vacancy, can be effective in identifying efficient R-P oxide structures for oxygen reduction reaction (ORR). Using a controlled synthesis method, well-defined nanostructures of R-P oxides are obtained, which along with thermochemical and electrochemical activity studies are used to validate the design principles. This has led to the identification of a highly active ORR electrocatalyst, nanostructured Co-doped lanthanum nickelate oxide, which when incorporated in solid oxide fuel cell cathodes significantly enhances the performance at intermediate temperatures (∼550 °C), while maintaining long-term stability. The reported findings demonstrate the effectiveness of the developed design principles to engineer mixed ionic-electronic conducting oxides for efficient oxygen electrocatalysis, and the potential of nanostructured Co-doped lanthanum nickelate oxides as promising catalysts for oxygen electrocatalysis.

16.
Eur J Rheumatol ; 4(3): 219-221, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29164004

RESUMO

Lipoma arborescens is a rare and benign intra-articular lesion of unknown etiology; it is characterized by synovial villous proliferation and sub-synovial connective tissue replacement by mature fatty tissue. It is part of the differential diagnosis in patients with an articulation affected by a slow, progressive, and chronically inflamed affection. We report primary knee involvement in a patient without significant articulate antecedents. Lipoma arborescens was diagnosed after knee magnetic resonance imaging and was confirmed by an anatomopathological study of the surgical specimen.

17.
Eur J Appl Physiol ; 117(6): 1257-1265, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28424870

RESUMO

PURPOSE: To compare the increases in upper- and lower-body muscle strength in premenopausal women performing resistance training (RT) alone or alongside concurrent high-intensity interval training (CT). METHODS: Sixteen women (26-40 years) were randomly assigned into two groups that performed either RT or CT. Both groups performed the same RT program; however, CT performed additional high-intensity interval training (HIIT) on a bicycle ergometer before RT. The study lasted 8 weeks and the participants were tested for ten repetition maximum (10RM) load in elbow flexion (barbell biceps curl) and knee extension exercises pre- and post-intervention. RT was performed with 10-12 repetitions to self-determined repetition maximum in the first four weeks and then progressed to 8-10. During CT, HIIT was performed before RT with six 1-min bouts at 7-8 of perceived subjective exertion (RPE) and then progressed to eight bouts at 9-10 RPE. RESULTS: Analysis of variance revealed significant increases in upper and lower body strength for both the RT and CT groups. Biceps barbell curl 10RM load increased from 12.9 ± 3.2 kg to 14 ± 1.5 kg in CT (p < 0.05) and from 13 ± 1.8 kg to 15.9 ± 2.5 kg in RT (p < 0.05), with no significant between-groups differences. Knee extension 10RM increase from 31.9 ± 11.6 kg to 37.5 ± 8.5 kg for CT (p < 0.05) and from 30.6 ± 8.6 kg to 41.2 ± 7.4 kg for RT (p < 0.05). CONCLUSION: In conclusion, performing HIIT on a cycle ergometer before resistance training does not seem to impair muscle strength increases in the knee extensors or elbow flexors of pre-menopausal women. This information should be considered when prescribing exercise sessions, since both activities may be combined without negative effects in muscle strength.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Força Muscular , Treinamento de Força/métodos , Adulto , Feminino , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Músculo Esquelético/fisiologia , Pré-Menopausa/fisiologia , Treinamento de Força/efeitos adversos
18.
Heart Rhythm ; 14(3): 448-454, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27777148

RESUMO

BACKGROUND: The capacity of catecholamines to induce ventricular tachycardia (VT) is well documented. OBJECTIVE: The effectiveness of the novel cardiac late sodium inhibitor eleclazine in suppressing catecholamine-induced VT in a large animal model was compared with that of flecainide. METHODS: In 13 closed-chest anesthetized Yorkshire pigs, spontaneous VT and surges in T-wave alternans (TWA) level measured using the Modified Moving Average method were induced by epinephrine (2.0 µg/kg, i.v., bolus over 1 minute). Effects of eleclazine (0.3 mg/kg, i.v., infused over 15 minutes; n = 6) or flecainide (1 mg/kg, i.v., bolus over 2 minutes followed by 1 mg/kg/hr, i.v., for 1 hour; n = 7) on VT incidence and TWA level were measured from right intraventricular electrogram recordings. RESULTS: Epinephrine reproducibly elicited hemodynamically significant spontaneous VT in all 13 pigs and increased TWA level by 33-fold compared to baseline (P < .001). Eleclazine reduced the incidence of epinephrine-induced ventricular premature beats and couplets by 51% (from 31.3 ± 1.91 to 15.2 ± 5.08 episodes; P = .038) and the incidence of 3- to 7-beat VT by 56% (from 10.8 ± 3.45 to 4.7 ± 3.12 episodes; P = .004). Concurrently, the drug reduced the peak epinephrine-induced TWA level by 64% (from 217 ± 22.2 to 78 ± 15.3 µV; P < .001). Flecainide also reduced the incidence of epinephrine-induced ventricular premature beats and couplets by 53% (from 40.4 ± 6.37 to 19.0 ± 2.73 episodes; P = .024) but did not affect the incidence of VT (from 15.0 ± 3.08 to 11.6 ± 2.93 episodes; P = .29) or the peak TWA level (from 207 ± 30.6 to 172 ± 26.2 µV; P = .34). CONCLUSION: Selective inhibition of cardiac late sodium current with eleclazine is more effective than flecainide in reducing catecholamine-induced VT and TWA in an intact porcine model.


Assuntos
Catecolaminas/metabolismo , Flecainida/farmacologia , Oxazepinas/farmacologia , Taquicardia Ventricular , Administração Intravenosa , Animais , Modelos Animais de Doenças , Monitoramento de Medicamentos/métodos , Eletrocardiografia/métodos , Hemodinâmica/efeitos dos fármacos , Suínos , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
19.
J Cachexia Sarcopenia Muscle ; 7(4): 413-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27239423

RESUMO

BACKGROUND: Human ageing is a process characterized by loss of muscle mass, strength, and bone mass. We aimed to examine the efficacy of low-dose creatine supplementation associated with resistance training on lean mass, strength, and bone mass in the elderly. METHODS: This was a 12-week, parallel-group, double-blind, randomized, placebo-controlled trial. The individuals were randomly allocated into one of the following groups: placebo plus resistance training (PL + RT) and creatine supplementation plus resistance training (CR + RT) . The participants were assessed at baseline and after 12 weeks. The primary outcomes were lean mass and strength, assessed by dual energy X-ray absorptiometry (DXA) and ten-repetition maximal tests (10 RM), respectively. Secondary outcomes included the lumbar spine, right and left femoral neck, both femur and whole body bone mineral density (BMD), and whole body bone mineral content (BMC), assessed by DXA. RESULTS: The CR + RT group had superior gains in lean mass when compared with the PL + RT group (P = 0.02). Changes in the 10 RM tests in bench press and leg press exercises, body composition, BMD, and BMC of all assessed sites did not significantly differ between the groups (P > 0.05). CONCLUSIONS: Twelve weeks of low-dose creatine supplementation associated with resistance training resulted in increases in lean mass in the elderly.

20.
Biomed Res Int ; 2015: 286369, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26526966

RESUMO

Schizophrenia (SZ) is a debilitating mental disorder characterized by psychotic events, abnormal social behavior, false beliefs, and auditory hallucinations. Hypermethylation of the promoter region of reelin (RELN), a gene involved in regulation of neuronal positioning during telencephalic development, is strongly associated with low protein expression in several cortical structures and promoter hypermethylation in brain from postmortem SZ subjects. Recent experimental data suggests that testosterone is able to promote RELN demethylation, although no direct evidence of hormonal influence on reelin promoter methylation was obtained. We investigated if reduced levels of plasma testosterone in adult male mice lead to Reln promoter demethylation. Animals were administered with flutamide, an antiandrogenic compound, and reelin promoter methylation was assessed using methylationspecific PCR using bisulfite DNA from cerebellum. We found that flutamide was able to significantly lower plasma testosterone when compared to control mice, and treatment did not influence animal survival and body weight. We also show that low plasma testosterone was associated with demethylation of a cytosine residue located at -860 in reelin promoter region. These preliminary data suggest that androgenic hormones can influence cerebral reelin demethylation. To our knowledge, this is the first experimental approach directly linking testosterone depletion and RELN promoter methylation.


Assuntos
Encéfalo/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Ilhas de CpG , Proteínas da Matriz Extracelular/genética , Proteínas do Tecido Nervoso/genética , Serina Endopeptidases/genética , Testosterona/sangue , Antagonistas de Androgênios/administração & dosagem , Antagonistas de Androgênios/metabolismo , Animais , Peso Corporal , Cerebelo/química , Citocinas/genética , Metilação de DNA , Modelos Animais de Doenças , Flutamida/administração & dosagem , Masculino , Camundongos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Proteína Reelina , Esquizofrenia/genética , Sulfitos/química , Testosterona/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...