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1.
J Hum Nutr Diet ; 32(2): 143-151, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30474895

RESUMO

BACKGROUND: Food insecurity (FI) impacted 15.7% (5.9 million) of US households with children in 2017. These households often experience issues within one or more of the food security pillars: access, availability, utilisation or stability. An underexplored area within the pillar of utilisation that may impact FI risk is the availability of kitchen equipment in households. This exploratory project aimed to quantify household food preparation equipment ownership and use by household FI status. METHODS: An online platform (Qualtrics, Provo, UT, USA) was used to administer a questionnaire to a sample of 135 parents of children aged 11-14 years. The instrument queried sociodemographic characteristics, food preparation items owned and frequency of use of 44 items within a 6-month interval. Household FI was measured using the 18-item US Department of Agriculture, Household Food Security Survey Module with a 12-month reference period. RESULTS: Households experiencing FI (n = 39; 28.9%) owned an average of five fewer items than their food secure counterparts (n = 96, 71.1%, P < 0.001), reporting lower item ownership within each equipment category subgroup (i.e. large appliances, small appliances, food preparation utensils and cooking utensils; all P < 0.01). There were no differences between FI and food secure households in frequency of use (all P > 0.01). CONCLUSIONS: Compared to food secure households, the number of food preparation items owned was lower, although frequency of use was the same, in US households that were FI. Future projects should investigate how food equipment ownership impacts cooking behaviours, and whether households experiencing FI display behaviours to compensate for a differing set of equipment.


Assuntos
Utensílios de Alimentação e Culinária/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Adolescente , Adulto , Criança , Estudos Transversais , Características da Família , Feminino , Humanos , Masculino , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos
2.
Sci Rep ; 7(1): 5147, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698554

RESUMO

Osteoarthritis (OA) is characterised by progressive destruction of articular cartilage and chondrocyte cell death. Here, we show the expression of the endogenous peptide urocortin1 (Ucn1) and two receptor subtypes, CRF-R1 and CRF-R2, in primary human articular chondrocytes (AC) and demonstrate its role as an autocrine/paracrine pro-survival factor. This effect could only be removed using the CRF-R1 selective antagonist CP-154526, suggesting Ucn1 acts through CRF-R1 when promoting chondrocyte survival. This cell death was characterised by an increase in p53 expression, and cleavage of caspase 9 and 3. Antagonism of CRF-R1 with CP-154526 caused an accumulation of intracellular calcium (Ca2+) over time and cell death. These effects could be prevented with the non-selective cation channel blocker Gadolinium (Gd3+). Therefore, opening of a non-selective cation channel causes cell death and Ucn1 maintains this channel in a closed conformation. This channel was identified to be the mechanosensitive channel Piezo1. We go on to determine that this channel inhibition by Ucn1 is mediated initially by an increase in cyclic adenosine monophosphate (cAMP) and a subsequent inactivation of phospholipase A2 (PLA2), whose metabolites are known to modulate ion channels. Knowledge of these novel pathways may present opportunities for interventions that could abrogate the progression of OA.


Assuntos
Cartilagem Articular/citologia , Canais Iônicos/química , Canais Iônicos/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Urocortinas/genética , Comunicação Autócrina , Cálcio/metabolismo , Cartilagem Articular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , AMP Cíclico/metabolismo , Humanos , Comunicação Parácrina , Fragmentos de Peptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Conformação Proteica , Pirimidinas/farmacologia , Pirróis/farmacologia , Transdução de Sinais , Urocortinas/metabolismo
3.
J Hum Nutr Diet ; 28(6): 593-603, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25231461

RESUMO

BACKGROUND: The present study aimed to explore facilitators and barriers to weight loss (WL) and weight loss maintenance (WLM) in women who participated in a primary, 18-week comparative trial that promoted WL with an energy-restricted diet. METHODS: Twenty-three women participated in seven focus groups conducted by a moderator and co-facilitator using open-ended questions and probes. Focus groups were held in a private room and audio tape-recorded. Tapes were transcribed verbatim and thematic analysis was used to evaluate transcripts for common themes. RESULTS: Accountability to others, social support, planning ahead, awareness and mindfulness of food choices, basic nutrition education, portion control, exercise, and self-motivation were perceived as key facilitators for WL and WLM by women. Identified barriers included life transitions, health status changes, internal factors, environmental pressures, lack of accountability and an absence of social support. CONCLUSIONS: Future interventions should address these salient facilitators and barriers to promote sustainable changes in women across their WL and WLM journeys.


Assuntos
Restrição Calórica/psicologia , Exercício Físico/psicologia , Preferências Alimentares/psicologia , Motivação/fisiologia , Pesquisa Qualitativa , Redução de Peso/fisiologia , Adulto , Comportamento de Escolha , Exercício Físico/fisiologia , Feminino , Grupos Focais , Preferências Alimentares/fisiologia , Nível de Saúde , Humanos , Apoio Social
4.
J Tissue Eng Regen Med ; 9(5): 595-604, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24945627

RESUMO

Fresh-frozen biological allograft remains the most effective substitute for the 'gold standard' autograft, sharing many of its osteogenic properties but, conversely, lacking viable osteogenic cells. Tissue engineering offers the opportunity to improve the osseointegration of this material through the addition of mesenchymal stem cells (MSCs). However, the presence of dead, immunogenic and potentially harmful bone marrow could hinder cell adhesion and differentiation, graft augmentation and incorporation, and wash procedures are therefore being utilized to remove the marrow, thereby improving the material's safety. To this end, we assessed the efficiency of a novel wash technique to produce a biocompatible, biological scaffold void of cellular material that was mechanically stable and had osteoinductive potential. The outcomes of our investigations demonstrated the efficient removal of marrow components (~99.6%), resulting in a biocompatible material with conserved biomechanical stability. Additionally, the scaffold was able to induce osteogenic differentiation of MSCs, with increases in osteogenic gene expression observed following extended culture. This study demonstrates the efficiency of the novel wash process and the potential of the resultant biological material to serve as a scaffold in bone allograft tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Transplante Ósseo , Osso e Ossos/patologia , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aloenxertos , Fenômenos Biomecânicos , Medula Óssea/patologia , Regeneração Óssea , Diferenciação Celular , Força Compressiva , Meios de Cultivo Condicionados/química , Feminino , Fêmur/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Osteogênese , Estresse Mecânico , Alicerces Teciduais
5.
Bone Joint Res ; 2(8): 169-78, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23958792

RESUMO

Mesenchymal stem-cell based therapies have been proposed as novel treatments for intervertebral disc degeneration, a prevalent and disabling condition associated with back pain. The development of these treatment strategies, however, has been hindered by the incomplete understanding of the human nucleus pulposus phenotype and by an inaccurate interpretation and translation of animal to human research. This review summarises recent work characterising the nucleus pulposus phenotype in different animal models and in humans and integrates their findings with the anatomical and physiological differences between these species. Understanding this phenotype is paramount to guarantee that implanted cells restore the native functions of the intervertebral disc. Cite this article: Bone Joint Res 2013;2:169-78.

6.
J Obes ; 2012: 460321, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23304462

RESUMO

Mortality risk across metabolic health-by-BMI categories in NHANES-III was examined. Metabolic health was defined as: (1) homeostasis model assessment-insulin resistance (HOMA-IR) <2.5; (2) ≤2 Adult Treatment Panel (ATP) III metabolic syndrome criteria; (3) combined definition using ≤1 of the following: HOMA-IR ≥1.95 (or diabetes medications), triglycerides ≥1.7 mmol/L, HDL-C <1.04 mmol/L (males) or <1.30 mmol/L (females), LDL-C ≥2.6 mmol/L, and total cholesterol ≥5.2 mmol/L (or cholesterol-lowering medications). Hazard ratios (HR) for all-cause mortality were estimated with Cox regression models. Nonpregnant women and men were included (n = 4373, mean ± SD, age 37.1 ± 10.9 years, BMI 27.3 ± 5.8 kg/m², 49.4% female). Only 40 of 1160 obese individuals were identified as MHO by all definitions. MHO groups had superior levels of clinical risk factors compared to unhealthy individuals but inferior levels compared to healthy lean groups. There was increased risk of all-cause mortality in metabolically unhealthy obese participants regardless of definition (HOMA-IR HR 2.07 (CI 1.3-3.4), P < 0.01; ATP-III HR 1.98 (CI 1.4-2.9), P < 0.001; combined definition HR 2.19 (CI 1.3-3.8), P < 0.01). MHO participants were not significantly different from healthy lean individuals by any definition. While MHO individuals are not at significantly increased risk of all-cause mortality, their clinical risk profile is worse than that of metabolically healthy lean individuals.


Assuntos
Inquéritos Nutricionais , Obesidade/mortalidade , Adulto , Causas de Morte , Feminino , Humanos , Resistência à Insulina , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Modelos de Riscos Proporcionais , Fatores de Risco
7.
Biotech Histochem ; 83(5): 239-45, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19016368

RESUMO

Intervertebral disc (IVD) degeneration is strongly associated with chronic low back pain, one of the most common causes of morbidity in the West. While normal healthy IVD is avascular, angiogenesis is a constant feature of IVD degeneration and has been shown to be associated with in-growth of nerves. Connective tissue growth factor (CTGF) plays a pivotal role in angiogenesis. To investigate the expression of CTGF in both normal and degenerated IVD, 21 IVDs were obtained from patients at surgery or postmortem examination and grouped according to the severity of histological degeneration. The immunohistochemical expression of CTGF was correlated with the degree of degeneration. CD31 immunohistochemistry was used to correlate IVD degeneration with vasculature. Our results showed that CTGF is expressed in non-degenerated and degenerated human IVDs and increased expression of CTGF is associated with degenerated discs, particularly within areas of neovascularization. We suggest that CTGF may play a role in angiogenesis in the human degenerated IVD.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Expressão Gênica , Disco Intervertebral/metabolismo , Neovascularização Patológica/metabolismo , Doenças da Coluna Vertebral/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Feminino , Humanos , Imuno-Histoquímica , Disco Intervertebral/patologia , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Doenças da Coluna Vertebral/patologia
8.
J Mol Histol ; 39(3): 303-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18247144

RESUMO

The nucleus pulposus (NP) of the human intervertebral disc (IVD) is a hyperosmotic tissue that is subjected to daily dynamic compressive loads. In order to survive within this environment the resident chondrocyte-like cells must be able to control their cell volume, whilst also controlling the anabolism and catabolism of their extra-cellular matrix. Recent studies have demonstrated expression of a range of bi-directional, transmembrane water and solute transporters, named aquaporins (AQPs), within chondrocytes of articular cartilage. The aim of this study was to use immunohistochemsitry to investigate the expression of aquaporins 1, 2 and 3 within the human IVD. Results demonstrated expression of both AQP-1 and -3 by cells within the NP and inner annulus fibrosus (AF), while outer AF cells lacked expression of AQP-1 and showed very low numbers of AQP-3 immunopositive cells. Cells from all regions were negative for AQP-2. Therefore this study demonstrates similarities in the phenotype of NP cells and articular chondrocytes, which may be due to similarities in tissue osmolarity and mechanobiology. The decrease in expression of AQPs from the NP to the outer AF may signify changes in cellular phenotype in response to differences in mechanbiology, osmolarity and hydration between the gelatinous NP and the fibrous AF.


Assuntos
Aquaporinas/metabolismo , Disco Intervertebral/metabolismo , Adolescente , Adulto , Idoso , Aquaporina 1/metabolismo , Aquaporina 2/metabolismo , Aquaporina 3/metabolismo , Biópsia , Feminino , Humanos , Imuno-Histoquímica , Disco Intervertebral/anatomia & histologia , Disco Intervertebral/citologia , Masculino , Pessoa de Meia-Idade
9.
Histochem Cell Biol ; 129(4): 503-11, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18172662

RESUMO

The glucose transporters GLUT-1 and GLUT-3 are targets of the hypoxia-inducible transcription factor HIF-1alpha and it has been shown that nucleus pulposus (NP) cells in rat intervertebral discs (IVD) express both HIF-1alpha and GLUT-1. However, there is limited data on the expression of HIF-1alpha and GLUTs in human IVD. The aim here was to (1) determine whether, like articular chondrocytes, human IVD cells express GLUT-1, 3 and 9 and whether there was any co-expression with HIF-1alpha; and (2) to localise expression of the GLUT isoforms in the disc and identify any changes during degeneration. Real-time PCR was used to identify expression of GLUT1, 3, 9 and HIF-1alpha mRNAs and immunohistochemistry was used to analyse protein expression and localisation of GLUTs in normal and degenerate IVD biopsies. Results confirmed HIF-1alpha, GLUT1, 3 and 9 mRNA expression in NP and AF and co-expression of each GLUT isoform with HIF-1alpha in the NP, but not the AF. Immunohistochemistry demonstrated regional differences in GLUT expression, with the highest expression being in the NP. GLUT expression also changed as degeneration progressed. This study demonstrates that NP and AF cells have different GLUT expression profiles that suggest regional differences in the metabolic nature of the human IVD and that this environment changes during degeneration.


Assuntos
Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Disco Intervertebral/fisiopatologia , Adolescente , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Feminino , Proteínas Facilitadoras de Transporte de Glucose/genética , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 3/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Disco Intervertebral/metabolismo , Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Distribuição Tecidual
10.
Histol Histopathol ; 22(9): 1033-41, 2007 09.
Artigo em Inglês | MEDLINE | ID: mdl-17523081

RESUMO

Degeneration of the intervertebral disc (IVD) is a major cause of low back pain affecting a large percentage of the population at some point in their lives. Consequently IVD degeneration and its associated low back pain has a huge socio-economic impact and places a burden on health services world-wide. Current treatments remove the symptoms without treating the underlying problem and can result in reoccurrence in the same or adjacent discs. Tissue engineering offers hope that new therapies can be developed which can regenerate the IVD. Combined with this, development of novel biomaterials and an increased understanding of mesenchymal stem cell and IVD cell biology mean that tissue engineering of the IVD may soon become a reality. However for any regenerative medicine approach to be successful there must first be an understanding of the biology of the tissue and the pathophysiology of the disease process. This review covers these key areas and gives an overview of the recent developments in the fields of biomaterials, cell biology and tissue engineering of the IVD.


Assuntos
Biologia , Disco Intervertebral/citologia , Disco Intervertebral/patologia , Medicina Regenerativa , Engenharia Tecidual , Animais , Materiais Biocompatíveis/uso terapêutico , Humanos , Deslocamento do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/terapia , Dor Lombar/etiologia , Transplante de Células-Tronco Mesenquimais
11.
Osteoporos Int ; 18(6): 789-96, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17264975

RESUMO

UNLABELLED: Women participated in 5 months of unilateral concentric (n = 37) or eccentric (n = 33) isokinetic resistance training of the legs and arms. Limb muscular strength increased as did total body, leg, and arm fat-free soft tissue mass, total body BMC, hip BMD, and forearm BMC and BMD. Isokinetic training benefits bone mineral acquisition. INTRODUCTION AND HYPOTHESIS: Isokinetic resistance training (IRT) is osteogenic; however, it is not known if concentric or eccentric modalities of IRT produce differential effects on bone. We tested our hypothesis that high-load eccentric versus concentric mode of IRT would produce greater increases in muscular strength, fat-free soft tissue mass (FFSTM), bone mineral density (BMD) and content (BMC) in trained legs and arms. METHODS: Participants were randomized to 5 months of concentric (n = 37) or eccentric (n = 33) training. The non-dominant leg and arm were used during training; dominant limbs served as controls. Muscular strength was measured with an isokinetic dynamometer; body composition was measured by dual-energy X-ray absorptiometry. RESULTS: Muscular strength of the concentrically and eccentrically trained leg (18.6%; 28.9%) and arm (12.5%; 24.6%) significantly increased with training. Gains in total body (TB) BMC (p < 0.05) and, in the trained limbs, total proximal femur BMD (p < 0.05) and total forearm BMD (p < 0.05) and BMC (p < 0.05) occurred in both groups. FFSTM increased for the TB and trained leg and arm (all p < 0.001) in both modes. CONCLUSION: Regardless of the mode, high-intensity, slow-velocity IRT increases muscular strength and FFSTM of trained limbs and imparts benefits to TB BMC and site-specific BMD and BMC in young women.


Assuntos
Densidade Óssea/fisiologia , Tecido Conjuntivo/anatomia & histologia , Exercício Físico/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Absorciometria de Fóton/métodos , Adolescente , Adulto , Antropometria/métodos , Braço/fisiologia , Composição Corporal/fisiologia , Feminino , Humanos , Perna (Membro)/fisiologia
12.
J Anim Sci ; 84(7): 1742-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16775058

RESUMO

This study was conducted to determine the effect of Se supplementation and source on the Se status of horses. Eighteen 18-mo-old nonexercised horses were randomly assigned within sex to 1 of 3 treatments: 1) control (CTRL, no supplemental Se, 0.15 mg of Se/kg of total diet DM); 2) inorganic Se (INORG, CTRL + 0.45 mg of Se/kg of total diet DM from NaSeO3); or organic Se [ORG, CTRL + 0.45 mg of Se/kg of total diet DM from zinc-L-selenomethionine (Availa Se, Zinpro, Corp., Eden Prairie, MN)]. Horses were acclimated to the CTRL diet (7.1 kg of DM alfalfa hay and 1.2 kg of DM concentrate per horse daily) for 28 d. After the acclimation period, the appropriate treatment was top-dressed on the individually fed concentrate for 56 d. Jugular venous blood samples were collected on d 0, 28, and 56. Middle gluteal muscle biopsies were collected on d 0 and 56. Muscle and plasma were analyzed for Se concentrations. Glutathione peroxidase activity was measured in muscle (M GPx-1), plasma (P GPx-3), and red blood cells (RBC GPx-1). Data were analyzed as a repeated measures design. Mean plasma Se concentration on d 28 and 56 was greater (P < 0.05) for Se-supplemented horses compared with CTRL horses, and tended (P < 0.1) to be greater in ORG vs. INORG on d 28. Mean muscle Se concentration and P GPx-3 activities increased (P < 0.05) from d 0 to 56 but were not affected by treatment. Mean RBC GPx-1 activity tended to be greater (P < 0.1) in ORG than INORG or CTRL horses on d 28, and tended to be greater (P < 0.1) for INORG compared with ORG horses on d 56. Mean RBC GPx-1 activity of INORG and ORG horses was not different from that of CTRL on d 56. Mean M GPx-1 activity decreased (P < 0.01) from d 0 to 56. In conclusion, zinc-L-selenomethionine was more effective than NaSeO3 at increasing plasma Se concentration from d 0 to 28; however, both supplemental Se sources had a similar effect by d 56. No difference in Se status due to Se supplementation or source could be detected over a 56-d supplementation period by monitoring middle gluteal muscle Se, M GPx-1, or P GPx-3. Results for RBC GPx-1 also were inconclusive relative to the effect of Se supplementation and source.


Assuntos
Cavalos/metabolismo , Compostos Organosselênicos/metabolismo , Selênio/metabolismo , Selênio/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Dieta/veterinária , Suplementos Nutricionais , Feminino , Glutationa Peroxidase/metabolismo , Masculino , Músculo Esquelético/química , Selênio/análise , Selênio/sangue
13.
J Dairy Sci ; 87(11): 3816-25, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15483166

RESUMO

The objectives of this investigation were to assess the relationship between chemical measures and imaging estimates (radiographic photometry and dual-energy x-ray absorptiometry) of bone mineral content in dairy cows and to evaluate the effects of parity, stage of lactation, and site of measurement (fused third and fourth metacarpal bone vs. caudal vertebrae 14 and 15) on bone mineral content. In a preliminary study, the caudal vertebrae were excised from 33 cows following slaughter. Samples were analyzed by radiographic photometry and then analyzed for mineral content chemically. In a second experiment, the caudal vertebrae and right front metacarpal (sample pairs) were excised from 107 Holstein cull cows following slaughter. Parity and days in milk (DIM) of the donor animals were obtained for 43 pairs of samples. Samples were grouped by parity (1, 2, 3, and >or=4) stage of lactation (Stage 1: <90 DIM, Stage 2: 90 to 150 DIM, Stage 3: 151 to 250 DIM, and Stage 4: >250 DIM). Samples were analyzed by radiographic photometry and dual-energy x-ray absorptiometry and then analyzed for mineral content chemically. In both experiments, the relationship between mineral content estimated via the imaging techniques and mineral content measured chemically was poor, likely because of the relative maturity of animals in the sample set and lack of variation in mineral content. Ash content was higher in the metacarpal than in the caudal vertebrae, as were concentrations of Mg (expressed as a proportion of bone ash). No effects of stage of lactation were observed on bone mineral in the caudal vertebrae, but in the metacarpal, P content (proportion of total mineral) was highest in second lactation cows. Total bone mineral content (ash) was not affected by parity in the metacarpal or caudal vertebra, but Ca and P content of the metacarpal increased with parity. Noninvasive imaging techniques are not sufficiently sensitive to detect changes in mineral content or composition of mature cows, and only modest changes in bone mineral were observed with stage of lactation and parity.


Assuntos
Absorciometria de Fóton/veterinária , Densidade Óssea/fisiologia , Bovinos/fisiologia , Paridade/fisiologia , Fotometria/veterinária , Matadouros , Absorciometria de Fóton/métodos , Animais , Cálcio/análise , Feminino , Metacarpo/diagnóstico por imagem , Fósforo/análise , Fotometria/métodos , Coluna Vertebral/diagnóstico por imagem
14.
Calcif Tissue Int ; 74(3): 229-35, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14517718

RESUMO

The purpose of this study was to examine the relationships among bone mineral density (BMD), body composition, and isokinetic strength in young women. Subjects were 76 women (age: 20 +/- 2 yr, height: 164 +/- 6 cm, weight: 57 +/- 6 kg, body fat: 27 +/- 4%) with a normal body mass index (18-25 kg/m(2)). Total body, nondominant proximal femur, and nondominant distal forearm BMD were measured with dual-energy x-ray absorptiometry. Isokinetic concentric (CON) and eccentric (ECC) strength of the nondominant thigh and upper arm were measured at 60 deg/sec. Fat-free mass (FFM) correlated (P < 0.001) with BMD of the total body (r = 0.56) and femoral neck (r = 0.52), whereas fat mass (FM) did not relate to BMD at any site. Leg FFM, but not FM, correlated with BMD in all regions of interest at the proximal femur. Weak associations were observed between arm FFM and forearm BMD. Isokinetic strength did not relate to BMD at any site after correcting for regional FFM. In conclusion, strong, independent associations exist between BMD and FFM, but not FM or isokinetic strength, in young women.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Antropometria , Braço , Feminino , Humanos , Contração Isométrica/fisiologia , Coxa da Perna
15.
Cell Mol Biol (Noisy-le-grand) ; 49(8): 1385-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14984014

RESUMO

5-Hydroxytryptamine (5-HT) is a vasoactive substance that is taken up by endothelial cells to activate endothelial nitrite oxide synthase (eNOS). The activation of eNOS results in the production of nitric oxide (NO), which is responsible for vasodilation of blood vessels. NO also interacts with superoxide anion (O2*-) to form peroxynitrite (ONOO-), a potent oxidant that has been shown to induce vascular endothelial dysfunction. We examined the ability of 3-morpholinosyndnonimine (SIN-1), an ONOO- generator, to inhibit 5-HT-induced phosphorylation of eNOS in cultured bovine aortic endothelial cells (BAECs). We observed that 5-HT phosphorylates Ser1179 eNOS in a time- and concentration-dependent manner. Maximum phosphorylation occurred at 30 sec using a concentration of 1.0 microM 5-HT. BAECs treated with SIN-1 (1-1000 microM) for 30 min showed no significant increase in eNOS phosphorylation. However, 5-HT-induced eNOS phosphorylation was inhibited in cells treated with various concentrations of SIN-1 for 30 min and stimulated with 5-HT. These data suggest that an increase in ONOO- as a result of an increase in the production of O2*-, may feedback to inhibit 5-HT-induced eNOS phosphorylation at Ser1179 and therefore, contribute to endothelial dysfunction associated with cardiovascular diseases.


Assuntos
Endotélio Vascular/citologia , Molsidomina/farmacologia , Óxido Nítrico Sintase/metabolismo , Antagonistas da Serotonina/farmacologia , Serotonina/farmacologia , Animais , Bovinos , Relação Dose-Resposta a Droga , Endotélio Vascular/enzimologia , Retroalimentação Fisiológica , Molsidomina/análogos & derivados , Óxido Nítrico Sintase Tipo III , Ácido Peroxinitroso/metabolismo , Fosforilação/efeitos dos fármacos
16.
Int J Sport Nutr Exerc Metab ; 11(2): 174-85, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11402251

RESUMO

The purpose of this investigation was to assess nutrition knowledge, opinions, and practices of coaches and trainers at a Division I university. Participants (n = 53) completed questionnaires regarding nutrition knowledge, opinions, and practices. Descriptive statistics and analysis of variance were used to analyze data. Overall, participants responded correctly to 67% of nutrition knowledge questions. Participants who coached/trained female athletes tended to score better than respondents who coached/trained male athletes. Strength and conditioning coaches and participants with greater than 15 years of experience scored higher than other participants. Nutrition opinions/practices responses revealed that nutritional supplements were provided for all but 6% of participants' athletes. Participants rated body weight as more important than body composition to athletes' performances. Over 30% of participants perceived at least one case of disordered eating within the past year. Some participants (53%) felt that athletes may consume more nutritious meals on team-sponsored trips if given larger food allowances. Thirty percent of participants reported dietitians were available to them; the same percentage reported utilizing dietitians. Coaches and trainers are knowledgeable about some appropriate nutritional recommendations, but registered dietitians or qualified sports nutrition professionals may complement the nutrition-related education and counseling of athletes (23).


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Fenômenos Fisiológicos da Nutrição , Esportes , Composição Corporal , Peso Corporal , Coleta de Dados , Suplementos Nutricionais , Humanos , Medicina Esportiva , Inquéritos e Questionários , Ensino , Universidades
18.
Med Sci Sports Exerc ; 32(1): 63-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10647531

RESUMO

PURPOSE: The purpose of this study was to examine bone mineral density (BMD), body composition, dietary intake, physical activity, and energy expenditure (EE) in premenarcheal gymnasts (N = 16; age = 10.5 +/- 1.5 yr) in comparison to age- (+/- 0.35 yr), height- (+/- 2.6 cm), and weight- (+/- 1.5 kg) matched controls (N = 16; age = 10.5 +/- 1.3 yr). It was hypothesized that premenarcheal gymnasts would have higher BMD, fat-free soft tissue (FFST) mass, physical activity, and EE, but lower fat mass, percent body fat, and dietary intake than controls. METHODS: Dual energy x-ray absorptiometry was used to measure whole body, femur, and lumbar spine (L1-4) BMD, FFST, and fat mass. Three-day diet records were used to estimate mean daily dietary energy, macronutrient, and calcium intakes. Physical activity and EE were estimated by the Seven-Day Physical Activity Recall. RESULTS: The BMD means of the gymnasts were significantly higher (P < 0.05) than controls at all sites, except whole body, as were lumbar spine and femoral neck bone mineral apparent densities, despite lower protein intake expressed per kg FFST mass. Fat mass was significantly lower in gymnasts versus controls (P < 0.01) as was percent body fat (P < 0.001). Very hard physical activity during weekdays (P < 0.0001) and estimated EE (P < 0.01) were significantly higher in gymnasts compared with controls. CONCLUSION: Premenarcheal gymnasts have higher BMD than age-, height-, and weight-matched controls.


Assuntos
Densidade Óssea , Ginástica/fisiologia , Menarca/fisiologia , Absorciometria de Fóton , Tecido Adiposo/anatomia & histologia , Adolescente , Composição Corporal/fisiologia , Índice de Massa Corporal , Osso e Ossos/anatomia & histologia , Cálcio da Dieta/administração & dosagem , Estudos de Casos e Controles , Criança , Dieta , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Metabolismo Energético/fisiologia , Feminino , Fêmur/anatomia & histologia , Colo do Fêmur/anatomia & histologia , Humanos , Vértebras Lombares/anatomia & histologia , Atividade Motora/fisiologia
19.
J Bone Miner Res ; 14(6): 994-1002, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10352109

RESUMO

Changes in bone mineral density (BMD), and related factors, in female child artistic gymnasts (n = 9) and their age- (+/-0.3 years), height- (+/-2.8 cm), and weight- (+/-1.7 kg) matched controls (n = 9) were prospectively examined. It was hypothesized that gymnasts would possess higher BMD at baseline, 6, and 12 months later and have greater gains in BMD over 1 year compared with controls. BMD (g/cm2) of the total proximal femur (TPF), Ward's triangle (WT), trochanter (Troch), femoral neck (FN), lumbar spine (LS, L1-L4), and total body (TB) were measured by dual-energy X-ray absorptiometry. Physical activity was measured by a 7-day recall; daily dietary intakes of energy and nutrients were estimated from 3-day records. Serum osteocalcin and urinary pyridinium cross-links were measured by radioimmunoassay and high performance liquid chromatography, respectively. Gymnasts versus controls possessed significantly higher BMD at all sites measured. Although not significantly different (p > 0.05), gymnasts compared with controls had moderately larger percentage changes in Troch (% Delta = 8.6 +/- 3.0 vs. 3.8 +/- 5.1%, d = 0.41), FN (% Delta = 6.1 +/- 1.2 vs. 3.9 +/- 1.6%, d = 0.55), LS (% Delta = 7.8 +/- 1.1 vs. 6.8 +/- 1.6%, d = 0.26), and TB BMD (% Delta = 5.6 +/- 0.8 vs. 3.4 +/- 0.7%, d = 0.98) as evidenced by the magnitude of the effect sizes (d). Gymnasts versus controls possessed a lower percentage body fat (p < 0.01) and engaged in more hours of very hard activity (p < 0.0001). Calcium, as a percentage of adequate intake, decreased over 12 months (p < 0.01), and urinary cross-links significantly decreased over 6 months in both groups. Female child gymnasts possess higher BMD at the TPF and related sites, LS, and TB compared with nongymnast controls, and 1 year of gymnastics training moderately increases Troch, FN, LS, and TB BMD for gymnasts compared with controls. These findings lend support to the idea that gymnastics training in childhood helps maximize peak BMD.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Ginástica , Tecido Adiposo/fisiologia , Adolescente , Antropometria , Biomarcadores , Estudos de Casos e Controles , Criança , Ingestão de Energia , Exercício Físico/fisiologia , Feminino , Humanos , Estado Nutricional , Estudos Prospectivos
20.
J Aging Health ; 9(1): 90-104, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10182412

RESUMO

Health-seeking behaviors are described by Harris and Guten (1979) as any behavior of an individual that promotes, protects, or maintains one's health, regardless of actual or perceived health status. The purpose of this study was to determine if nutritional health-seeking behavior (Bausell, 1986) comprised one or more factors for older adults (N = 256). Participants were in their 60s (n = 90), 80s (n = 91), and 100+ (n = 75). Exploratory factor analysis indicated that nutritional health-seeking behavior items formed two factors: avoid (i.e., avoiding unhealthy nutritional behavior) and seek (i.e., attempting or seeking healthy nutritional behavior). Multiple regression analysis revealed that risk factors for poor nutritional health-seeking behaviors in older adults include advanced age, low economic resources, and male gender. Protective factors included in the personality factors of self-discipline, enthusiasm, sensitivity, and warmth.


Assuntos
Fatores Etários , Comportamentos Relacionados com a Saúde , Fenômenos Fisiológicos da Nutrição , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Estudos de Coortes , Feminino , Nível de Saúde , Humanos , Masculino , Análise de Regressão , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos
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