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1.
Cell ; 166(3): 651-663, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27374333

RESUMO

Cellular bodies such as P bodies and PML nuclear bodies (PML NBs) appear to be phase-separated liquids organized by multivalent interactions among proteins and RNA molecules. Although many components of various cellular bodies are known, general principles that define body composition are lacking. We modeled cellular bodies using several engineered multivalent proteins and RNA. In vitro and in cells, these scaffold molecules form phase-separated liquids that concentrate low valency client proteins. Clients partition differently depending on the ratio of scaffolds, with a sharp switch across the phase diagram diagonal. Composition can switch rapidly through changes in scaffold concentration or valency. Natural PML NBs and P bodies show analogous partitioning behavior, suggesting how their compositions could be controlled by levels of PML SUMOylation or cellular mRNA concentration, respectively. The data suggest a conceptual framework for considering the composition and control thereof of cellular bodies assembled through heterotypic multivalent interactions.


Assuntos
Células Artificiais/química , Compartimento Celular , Organelas/química , Proteínas/química , Motivos de Aminoácidos , Composição Corporal , Proteínas de Transporte/química , Linhagem Celular , Núcleo Celular/química , Citoplasma , Eletroquímica , Células HeLa , Humanos , Técnicas In Vitro , Estrutura Molecular , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , Engenharia de Proteínas , Ubiquitinas/química , Leveduras
2.
BMC Cancer ; 24(1): 493, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637770

RESUMO

BACKGROUND: Muscle mass is important for metastatic prostate cancer survival and quality of life (QoL). The backbone of treatment for men with metastatic castration sensitive prostate cancer (mCSPC) is androgen deprivation therapy (ADT) with an androgen signaling inhibitor. ADT is an effective cancer treatment, but it facilitates significant declines in muscle mass and adverse health outcomes important to mCSPC survivors, such as fatigue, and reductions in physical function, independence, insulin sensitivity, and QoL. In non-metastatic CSPC survivors, resistance training (RT) preserves muscle mass and improves these related health outcomes, but the biggest barrier to RT in CSPC survivors of all stages is fatigue. Creatine monohydrate supplementation coupled with RT (Cr + RT) may address this barrier since creatine plays a critical role in energy metabolism. Cr + RT in cancer-free older adults and other clinical populations improves muscle mass and related health outcomes. Evidence also suggests that creatine supplementation can complement cancer treatment. Thus, Cr + RT is a strategy that addresses gaps in survivorship needs of people with mCSPC. The purpose of this parallel, double-blind randomized controlled trial is to test the effects of 52-weeks of Cr + RT compared with placebo (PLA) and RT (PLA + RT) on muscle mass, other related health outcomes, and markers of cancer progression. METHODS: We will carry out this trial with our team's established, effective, home-based, telehealth RT program in 200 mCSPC survivors receiving ADT, and evaluate outcomes at baseline, 24-, and 52-weeks. RT will occur twice weekly with elastic resistance bands, and an established creatine supplementation protocol will be used for supplementation delivery. Our approach addresses a major facilitator to RT in mCSPC survivors, a home-based RT program, while utilizing a supervised model for safety. DISCUSSION: Findings will improve delivery of comprehensive survivorship care by providing a multicomponent, patient-centered lifestyle strategy to preserve muscle mass, improve health outcomes, and complement cancer treatment (NCT06112990).


Assuntos
Neoplasias da Próstata , Treinamento Resistido , Masculino , Humanos , Idoso , Creatina/uso terapêutico , Creatina/farmacologia , Qualidade de Vida , Antagonistas de Androgênios/uso terapêutico , Neoplasias da Próstata/patologia , Androgênios , Força Muscular , Composição Corporal , Processos Neoplásicos , Método Duplo-Cego , Suplementos Nutricionais/efeitos adversos , Músculos/patologia , Poliésteres/farmacologia , Poliésteres/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
BMC Palliat Care ; 23(1): 209, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160544

RESUMO

BACKGROUND: Oral fluid intake decreases in advanced cancer in the dying phase of illness. There is inadequate evidence to support the assessment, and management, of hydration in the dying. Bioelectrical impedance analysis (BIA) is a body composition assessment tool. BIA has the potential to inform clinal management in advanced cancer, by examining the relationships between hydration status and clinical variables. AIM: BIA was used to determine the association between hydration status, symptoms, clinical signs, quality-of-life and survival in advanced cancer, including those who are dying (i.e. in the last week of life). MATERIALS AND METHODS: We conducted a prospective observational study of people with advanced cancer in three centres. Advance consent methodology was used to conduct hydration assessments in the dying. Total body water was estimated using the BIA Impedance index (Height - H (m)2 /Resistance - R (Ohms)). Backward regression was used to identify factors (physical signs, symptoms, quality of life) that predicted H2/R. Participants in the last 7 days of life were further assessed with BIA to assess hydration changes, and its relationship with clinical outcomes. RESULTS: One hundred and twenty-five people participated (males n = 74 (59.2%), females, n = 51 (40.8%)). We used backward regression analysis to describe a statistical model to predict hydration status in advanced cancer. The model demonstrated that 'less hydration' (lower H2/R) was associated with female sex (Beta = -0.39, p < 0.001), increased appetite (Beta = -0.12, p = 0.09), increased dehydration assessment scale score (dry mouth, dry axilla, sunken eyes - Beta = -0.19, p = 0.006), and increased breathlessness (Beta = -0.15, p = 0.03). 'More hydration' (higher H2/R) was associated with oedema (Beta = 0.49, p < 0.001). In dying participants (n = 18, 14.4%), hydration status (H2/R) was not significantly different compared to their baseline measurements (n = 18, M = 49.6, SD = 16.0 vs. M = 51.0, SD = 12.1; t(17) = 0.64, p = 0.53) and was not significantly associated with agitation (rs = -0.85, p = 0.74), pain (rs = 0.31, p = 0.23) or respiratory tract secretions (rs = -0.34, p = 0.19). CONCLUSIONS: This is the first study to use bioimpedance to report a model (using clinical factors) to predict hydration status in advanced cancer. Our data demonstrates the feasibility of using an advance consent method to conduct research in dying people. This method can potentially improve the evidence base (and hence, quality of care) for the dying. Future BIA research can involve hydration assessment of cancers (according to type and stage) and associated variables (e.g., stage of illness, ethnicity and gender). Further work can use BIA to identify clinically relevant outcomes for hydration studies and establish a core outcome set to evaluate how hydration affects symptoms and quality-of-life in cancer.


Assuntos
Impedância Elétrica , Neoplasias , Qualidade de Vida , Humanos , Feminino , Masculino , Neoplasias/complicações , Neoplasias/psicologia , Estudos Prospectivos , Idoso , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Desidratação/diagnóstico , Desidratação/fisiopatologia , Idoso de 80 Anos ou mais , Estado de Hidratação do Organismo/fisiologia , Composição Corporal/fisiologia , Água Corporal , Adulto
4.
J Strength Cond Res ; 38(7): e359-e365, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38662930

RESUMO

ABSTRACT: Redinger, AL, Russell, JL, Allen, SMF, and Baker, BS. Height restrictions for dual-energy X-ray absorptiometry: what are our options for body composition and bone health precision? J Strength Cond Res 38(7): e359-e365, 2024-Dual-energy X-ray absorptiometry (DXA) is commonly used for testing athlete's body composition, but many athletes are too tall. The first aim was to assess the viability of combining upper- and lower-body regions of interest (ROI), creating a combined scan for tall athletes who do not fit on the table and second, to provide practical solutions to DXA users who routinely scan tall athletes. Sixty subjects (34.8 ± 11.9 years; 171 ± 9 cm) completed 2 total-body DXA scans for baseline precision testing, using GE Lunar Prodigy (LP) or Hologic Horizon A (HA) models. Next, an upper body ROI from the skull to the distal femoral condyles was combined with a flipped scan (feet-to-head) ROI encompassing the proximal tibial plateau to the distal foot. Soft and bone tissue coefficient of variance (CV%) were calculated between the baseline scans and for the newly combined ROI scan. The combined ROI scan added 0.25-0.63% and 0.01-4.35% error rates for the LP and HA, respectively. An exploratory assessment of a GE Lunar iDXA demonstrated results similar to the HA with 4%+ error. The combined ROI scan is a user-friendly and precise method for older LP systems adding less than 1% error; however, newer DXA systems cannot use the stitched scan technique. Coaches and practitioners who use newer DXAs must prioritize consistently using the same boney landmarks (head, jaw, or feet) and ROI heights to provide precise longitudinal assessments of tall athletes' bone and body composition, until larger DXA tables become available.


Assuntos
Absorciometria de Fóton , Composição Corporal , Estatura , Densidade Óssea , Humanos , Masculino , Adulto , Composição Corporal/fisiologia , Feminino , Densidade Óssea/fisiologia , Atletas , Pessoa de Meia-Idade , Adulto Jovem
5.
Chin J Physiol ; 66(6): 485-493, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149561

RESUMO

Acute body mass loss before competitions in combat sports usually leads to loss in fat-free mass. Beta-hydroxy-beta-methylbutyrate (HMB) has been shown to increase skeletal muscle mass and muscle strength in various muscle wasting conditions. This study investigated the effect of HMB supplementation on body composition and sport-specific performance in well-trained boxers consuming a hypocaloric diet. Twelve male college boxers were divided into the HMB and placebo (PLA) groups using a body weight-matched single-blind parallel design. The study comprised a 6-day weight loss period (days 1-6), followed by a 3-day competition period (days 7-9). The participants in both the groups consumed 16 kcal/kg/day, including 1.6-1.7 g/kg of carbohydrates, 1.2-1.3 g/kg of protein, and 0.45-0.5 g/kg of fat during the 9-day period. The HMB group consumed 3 g/day HMB. Body composition measurement, isometric mid-thigh pull (IMTP), and a simulated boxing match were performed at baseline and on days 7, 8, and 9. Fasting blood samples were collected on the day before day 1 and on days 7, 8, and 9. Body mass was significantly decreased after the 6-day weight loss period (HMB group: baseline: 69.4 ± 11.2 kg, day 7: 67.1 ± 11.2 kg; PLA group: baseline: 68.6 ± 12.1 kg, day 7: 65.7 ± 11.5 kg, P < 0.05) while it was unchanged on the 3-day competition period in both the groups. Fat-free mass in the HMB group was maintained throughout the 9-day period (baseline: 56.7 ± 9.3 kg, day 7: 56.3 ± 8.7 kg, day 9: 55.8 ± 9.5 kg) whereas it significantly decreased on days 7 and 9 compared to the baseline in the PLA group (baseline: 55.2 ± 6.4 kg, day 7: 54.1 ± 6.6 kg, day 9: 54.0 ± 6.6 kg, P < 0.05). In the PLA group, the average and maximal heart rates in round 1 and the average heart rate in round 2 on days 8 and 9 were significantly lower than those at baseline, while these parameters were unchanged in the HMB group. The maximal force and the rate of force development in the IMTP remained unchanged among the different timepoints in both the groups. The blood biochemical parameters were similar at any timepoint between the PLA and HMB groups. HMB supplementation during acute weight loss may preserve fat-free mass and maintain heart rate response in subsequent simulated matches in well-trained boxers. In addition, HMB supplementation had a nonsignificant effect on glucose, fat, and protein metabolism during energy restriction.


Assuntos
Dieta Redutora , Suplementos Nutricionais , Humanos , Masculino , Composição Corporal , Músculo Esquelético/fisiologia , Obesidade , Poliésteres/farmacologia , Método Simples-Cego , Redução de Peso
6.
J Sports Sci Med ; 22(3): 541-548, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37711701

RESUMO

The combined exercise with citrulline (CIT) supplementation is a potential adjuvant treatment approach to address the declining body composition and lower limb function of overweight older adults. However, research on this approach is limited. Thus, this study performed a meta-analysis review to explore the effects of combined exercise with CIT supplementation on body composition and lower limb function among overweight older adults. The search strategy and manuscript development of this study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Eligible studies were first searched through four databases (Web of Science, Scopus, PubMed, and EBSCO) from January 2003 until April 2023, followed by screening. The main inclusion criteria for the article selection are as follows: 1) Randomized Controlled Trial studies; 2) Participants aged over 55; 3) Studies involved exercise with CIT supplementation for the experimental group and exercise with Placebo (PLA) supplementation for the control group; 4) Body composition and lower limb function were measured at pre- and post-intervention. Subsequently, the Cochrane risk of bias assessment tool was utilized to evaluate the selected studies' quality. The Standardized Mean Difference (SMD) was chosen as the suitable effect scale index, and the mean differences of the data from the selected articles were analyzed using Revman 5.4 software with a 95% Confidence Interval (CI). A total of seven studies fulfilled the inclusion criteria and were selected for the meta-analysis. The included studies involved 105 males and 198 females, where 157 belonged to the PLA group and 146 from the CIT group. Significant improvements were observed among overweight older adults with CIT supplementation in 6-Minute Walking Test (6MWT) (P = 0.04, I2 = 4%), SMD (95% CI) = -0.28 (-0.54, -0.01), and Lower Limb Strength (LLS) (P < 0.01, I2 = 30%), SMD (95% CI) = -0.38 (-0.65, -0.12) compared to those with PLA supplementation. Combined exercise with CIT supplementation could be an effective non-pharmaceutical intervention to improve the physical function of overweight older adults by increasing their muscle strength.


Assuntos
Citrulina , Sobrepeso , Feminino , Masculino , Humanos , Idoso , Sobrepeso/terapia , Composição Corporal , Extremidade Inferior , Suplementos Nutricionais , Poliésteres
7.
Stomatologiia (Mosk) ; 102(2): 16-20, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37144763

RESUMO

OBJECTIVE: To increase the effectiveness of the diagnosis and treatment of dental diseases, based on the study of anthropometric and bioimpedance analysis data in adolescents and adult patients to identify the effect of overweight on dental status. MATERIAL AND METHODS: The study involved 60 adolescents aged 15-18 years, 28 of whom were overweight, and 32 with normal body weight. All 52 adult patients aged 30-50 years who participated in the study were overweight (body mass index >25 kg/m2) and had chronic generalized periodontitis. In all patients dental status was assessed by DMF and PMA index, Silness-Loe and Stallard hygienic indices, Muleman bleeding index, Green-Vermillion tartar index. Biochemical parameters of the oral fluid were also evaluated: malondialdehyde, elastase, urease, catalase and lysozyme activity. The adolescents underwent an anthropometric study with the determination of body mass index. Adult patients underwent bioimpedance analysis of body composition to determine the main indicators of fat metabolism in the body: body mass index, fat mass (kg), the proportion of adipose tissue (%) and the mass of extracellular fluid (kg). RESULTS: The study showed that overweight in patients of different ages worsens their dental status and biochemical parameters of oral fluid. CONCLUSION: The inclusion of an anthropometric study with the determination of body mass index and bioimpedance analysis of body composition in the examination of dental patients will allow the development of individual programs for the prevention of dental diseases, implementing a personalized approach to the provision of medical and preventive care.


Assuntos
Sobrepeso , Doenças Estomatognáticas , Adulto , Adolescente , Humanos , Sobrepeso/complicações , Obesidade , Índice de Massa Corporal , Composição Corporal
8.
BMC Oral Health ; 22(1): 147, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477491

RESUMO

BACKGROUND: To determine the impact of dental status, types, and quality of dental prostheses on body composition, masticatory performance and oral health-related quality of life (OHRQoL). Potential associations between body composition, masticatory performance and OHRQoL were also investigated. METHODS: This cross-sectional study included 110 older adults who received prosthodontic treatment at the Dental Faculty Clinics at Chulalongkorn University. Participants were categorized according to their dental prostheses: complete denture (CD), removable partial denture (RPD) and fixed partial denture (FPD). Retention and stability of the RPD and CD were evaluated using the CU-modified Kapur and the modified NHANES III criteria to classify denture quality into acceptable and unacceptable. Dental status including posterior occluding pairs and number of remaining natural teeth were assessed intraorally. Dependent variables were body composition, masticatory performance and OHRQoL. Body composition, including muscle mass (kg), bone mass (kg), basal metabolic rate (kcal) and visceral fat (%) were determined through a bioelectrical impedance analysis. Masticatory performance was assessed using a multiple sieve method of peanut mastication. OHRQoL was assessed using the validated Thai version of Oral Impacts on Daily Performances (Thai-OIDP) index. After adjusting for covariates, including age and sex, the associations between oral and dental prosthesis status and body composition, masticatory performance as well as OIDP score were analyzed using multivariable linear and negative binomial regression analyses. Spearman's correlation was used to determine the potential associations between body composition, masticatory performance and OHRQoL. RESULTS: The presence of fewer natural teeth or wearing an unacceptable removable denture were factors associated with lower bone mass, muscle mass and basal metabolic rate, and with a higher visceral fat. Similar dental and removable denture status were also associated with larger peanut particle size and higher OIDP score. Masticatory performance and OHRQoL variables were moderately correlated (Spearman's rho = 0.44). However, body composition was not correlated with masticatory performance or OHRQoL. CONCLUSIONS: In individuals wearing dental prostheses, factors such as severity of tooth loss, types, and quality of dental prostheses, particularly retention and stability, negatively impacted not only masticatory function and OHRQoL, but also their overall body composition and health.


Assuntos
Boca Edêntula , Qualidade de Vida , Idoso , Composição Corporal , Estudos Transversais , Prótese Total , Humanos , Inquéritos Nutricionais , Saúde Bucal
10.
Br J Nutr ; 124(4): 457-469, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32172691

RESUMO

Less invasive protocols are necessary to study energy expenditure (EE) of cats living in homes for expressing their normal living conditions. The present study compared sampling times and the use of saliva, urine and blood to measure 2H and 18O to apply the doubly labelled water method. In the first study, four cats were used to evaluate the enrichment (2, 4, 6, 7 and 8 h) and elimination (2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 d) of 2H and 18O (subcutaneously injected). The maximum enrichment was after 5 h (R2 0·82) of injection, with an Ln linear elimination of both isotopes (P < 0·001; R2 0·99). The results of EE were similar, regardless of the sampling time used (P = 0·999). In the second study, seven male cats and seven female cats were used. Before and after isotope injection (5 h, 7 d, 10 d and 14 d), blood, saliva and urine were collected. Isotope enrichment was lower in urine (P < 0·05) and at the similar level in blood and saliva. Isotope elimination was similar for all fluids (P < 0·473). The EE calculated with blood and saliva was similar but higher for urine (P = 0·015). According to Bland-Altman statistics, blood and saliva presented low bias and high correlation (P < 0·001), but this was not observed for urine (P = 0·096). Higher EE was observed for male cats (384 (se 39) kJ/kg0·67 per d) than for female cats (337 (se 34) kJ/kg0·67 per d; P < 0·05). The sampling time for the method is flexible, and saliva can be used as a substitute for blood.


Assuntos
Composição Corporal/fisiologia , Água Corporal/metabolismo , Metabolismo Energético/fisiologia , Saliva/química , Urina/química , Animais , Gatos , Deutério/análise , Feminino , Masculino , Isótopos de Oxigênio/análise
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