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1.
PLoS One ; 15(8): e0237042, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813735

RESUMO

The largest dinosaurs were enormous animals whose body mass placed massive gravitational loads on their skeleton. Previous studies investigated dinosaurian bone strength and biomechanics, but the relationships between dinosaurian trabecular bone architecture and mechanical behavior has not been studied. In this study, trabecular bone samples from the distal femur and proximal tibia of dinosaurs ranging in body mass from 23-8,000 kg were investigated. The trabecular architecture was quantified from micro-computed tomography scans and allometric scaling relationships were used to determine how the trabecular bone architectural indices changed with body mass. Trabecular bone mechanical behavior was investigated by finite element modeling. It was found that dinosaurian trabecular bone volume fraction is positively correlated with body mass similar to what is observed for extant mammalian species, while trabecular spacing, number, and connectivity density in dinosaurs is negatively correlated with body mass, exhibiting opposite behavior from extant mammals. Furthermore, it was found that trabecular bone apparent modulus is positively correlated with body mass in dinosaurian species, while no correlation was observed for mammalian species. Additionally, trabecular bone tensile and compressive principal strains were not correlated with body mass in mammalian or dinosaurian species. Trabecular bone apparent modulus was positively correlated with trabecular spacing in mammals and positively correlated with connectivity density in dinosaurs, but these differential architectural effects on trabecular bone apparent modulus limit average trabecular bone tissue strains to below 3,000 microstrain for estimated high levels of physiological loading in both mammals and dinosaurs.


Assuntos
Osso Esponjoso/anatomia & histologia , Osso Esponjoso/fisiologia , Dinossauros/anatomia & histologia , Animais , Anisotropia , Fenômenos Biomecânicos , Densidade Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Força Compressiva/fisiologia , Simulação por Computador , Fêmur/anatomia & histologia , Análise de Elementos Finitos , Fósseis , Processamento de Imagem Assistida por Computador/métodos , Mamíferos/anatomia & histologia , Estresse Mecânico , Tíbia/anatomia & histologia , Microtomografia por Raio-X/métodos
2.
Sports Health ; 12(5): 441-448, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32660392

RESUMO

BACKGROUND: Physical activity (PA) and physical fitness (PF) are crucial for bone health. However, children participating in competitive sports with high PA are at a greater risk of fracture from trauma or overuse. Given the importance of bone development during adolescence, associations between commonly used physical fitness tests with distal third radius (R-SoS) and midshaft tibia (T-SoS) speed of sound by quantitative ultrasound were assessed in adolescent athletes and nonathletes. HYPOTHESIS: The relationship between physical fitness tests and R-SoS and T-SoS will differ depending on sex and athletic status. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: Physical fitness of 285 boys (156 athletes) and 311 girls (74 athletes) aged 10 to 18 years was assessed through strength, speed, agility, and cardiorespiratory tests. Linear regression was used to assess the associations of physical fitness tests with R-SoS and T-SoS. RESULTS: For boys, favorable associations were observed between physical fitness tests with R-SoS in athletes and T-SoS in both athletes and nonathletes (P < 0.05). For nonathlete girls, favorable associations were found for handgrip (R-SoS and T-SoS, both P < 0.05), whereas the progressive aerobic cardiovascular endurance run, vertical jump, speed at 20 m and 40 m were only favorably associated with T-SoS. For athlete girls, the association between handgrip (P = 0.03), vertical jump, and 4 × 10 m shuttle run (P < 0.05) with T-SoS was significantly related to a bone outcome. CONCLUSION: The handgrip test and vertical jump were associated with T-SoS in boys and girls independent of sport status. These results suggest that physical fitness is associated with bone health in adolescents, particularly boys, and that the relationship between physical fitness and bone may differ depending on sex and athletic status. CLINICAL RELEVANCE: Physical fitness tests are simple, easy-to-use tools for monitoring bone health and should be used by sport and health professsionals to promote healthy sport participation and prevent bone injuries.


Assuntos
Teste de Esforço/métodos , Aptidão Física/fisiologia , Rádio (Anatomia)/fisiologia , Esportes/fisiologia , Tíbia/fisiologia , Adolescente , Densidade Óssea/fisiologia , Criança , Estudos Transversais , Feminino , Força da Mão , Humanos , Masculino , Rádio (Anatomia)/diagnóstico por imagem , Fatores Sexuais , Tíbia/diagnóstico por imagem , Ultrassonografia
3.
Lancet Diabetes Endocrinol ; 8(8): 672-682, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32707115

RESUMO

BACKGROUND: The validation of bone mineral density (BMD) as a surrogate outcome for fracture would allow the size of future randomised controlled osteoporosis registration trials to be reduced. We aimed to determine the association between treatment-related changes in BMD, assessed by dual-energy x-ray absorptiometry, and fracture outcomes, including the proportion of treatment effect explained by BMD changes. METHODS: We did a pooled analysis of individual patient data from multiple randomised placebo-controlled clinical trials. We included data from multicentre, randomised, placebo-controlled, double-blind trials of osteoporosis medications that included women and men at increased osteoporotic fracture risk. Using individual patient data for each trial we calculated mean 24-month BMD percent change together with fracture reductions and did a meta-regression of the association between treatment-related differences in BMD changes (percentage difference, active minus placebo) and fracture risk reduction. We also used individual patient data to determine the proportion of anti-fracture treatment effect explained by BMD changes and the BMD change needed in future trials to ensure fracture reduction efficacy. FINDINGS: Individual patient data from 91 779 participants of 23 randomised, placebo-controlled trials were included. The trials had 1-9 years of follow-up and included 12 trials of bisphosphonate, one of odanacatib, two of hormone therapy (one of conjugated equine oestrogen and one of conjugated equine oestrogen plus medroxyprogesterone acetate), three of PTH receptor agonists, one of denosumab, and four of selective oestrogen receptor modulator trials. The meta-regression revealed significant associations between treatment-related changes in hip, femoral neck, and spine BMD and reductions in vertebral (r2 0·73, p<0·0001; 0·59, p=0·0005; 0·61, p=0·0003), hip (0·41, p=0·014; 0·41, p=0·0074; 0·34, p=0·023) and non-vertebral fractures (0·53, p=0·0021; 0·65, p<0·0001; 0·51, p=0·0019). Minimum 24-month percentage changes in total hip BMD providing almost certain fracture reductions in future trials ranged from 1·42% to 3·18%, depending on fracture site. Hip BMD changes explained substantial proportions (44-67%) of treatment-related fracture risk reduction. INTERPRETATION: Treatment-related BMD changes are strongly associated with fracture reductions across randomised trials of osteoporosis therapies with differing mechanisms of action. These analyses support BMD as a surrogate outcome for fracture outcomes in future randomised trials of new osteoporosis therapies and provide an important demonstration of the value of public access to individual patient data from multiple trials. FUNDING: Foundation for National Institutes of Health.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Interpretação Estatística de Dados , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Absorciometria de Fóton/métodos , Biomarcadores/metabolismo , Densidade Óssea/fisiologia , Humanos , Fraturas por Osteoporose/metabolismo , Análise de Regressão , Comportamento de Redução do Risco , Resultado do Tratamento
4.
Medicine (Baltimore) ; 99(28): e20906, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664083

RESUMO

Osteoporosis (OP) is a metabolic bone disease that can cause structural changes in bone marrow cavity. Bone marrow is the hematopoietic organ of adults. Accumulating evidence has shown a close connection between bone marrow hematopoietic function and bone formation. Some studies have revealed that OP is associated with hematopoiesis. However, the relationship is not definite.This study aimed to evaluate the association between peripheral blood cell counts (white blood cells [WBC], red blood cells [RBC], platelets [PLT]), hemoglobin [HGB], and bone mineral density [BMD]) in a sample of Chinese postmenopausal women. This is a retrospective study involving 673 postmenopausal women cases. The BMD of lumbar spine and left hip joint were measured by dual-energy X-ray absorptiometry. The levels of blood cell counts and HGB were measured and analyzed.The study results showed the WBC, RBC, PLT, and HGB levels of postmenopausal women in the OP group were all higher than those in the non-osteoporosis group. Spearman linear trend analysis and partial correlation analysis demonstrated that BMD was negatively correlated with WBC, RBC, PLT, and HGB in postmenopausal women.Due to the differences between different countries and races, and there are few studies on the association of BMD with peripheral blood cell counts and HGB in Chinese Postmenopausal Women. Therefore, more large sample studies are needed.


Assuntos
Grupo com Ancestrais do Continente Asiático/etnologia , Contagem de Células Sanguíneas/métodos , Densidade Óssea/fisiologia , Hemoglobinas/análise , Pós-Menopausa/sangue , Absorciometria de Fóton/métodos , Idoso , Contagem de Células Sanguíneas/tendências , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/fisiopatologia , Estudos de Casos e Controles , Feminino , Hematopoese/fisiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteogênese/fisiologia , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Estudos Retrospectivos
5.
Sports Health ; 12(4): 334-340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525466

RESUMO

BACKGROUND: Female runners are at increased risk of stress fractures (SFs) compared with men. Literature is lacking with regard to best practice for preventing and treating SFs in women. The purpose of the study was to compare physiological measures and running-related factors between women of various ages and running abilities with and without a history of running-related SFs. HYPOTHESIS: Women with and without SF histories will differ with regard to medical and menstrual history, bone health, body composition, nutrition, and running history. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 20 female runners with SF histories were matched based on age and running distance with 20 women without SF histories. Data included medical, menstrual, running, injury, and nutritional histories; blood histology related to nutritional, hormonal, and bone-related risk factors; and bone density, fat, and lean tissue using dual energy x-ray absorptiometry. Paired t tests were used to examine differences between women with and without SF histories, and Spearmen correlations were conducted to examine relationships between physiological factors. RESULTS: Women with SF histories had lower hip bone mineral density compared with women without SF histories (P < 0.05). SF history was moderately correlated with menstrual changes during increased training times (r = 0.580; P < 0.0001) but was not correlated with any other physiological factor. There was a moderate correlation within the SF group (r = 0.65; P = 0.004) for bone markers for resorption and formation both increasing, indicating increased bone turnover. CONCLUSION: Female runners with low hip bone mineral density, menstrual changes during peak training, and elevated bone turnover markers may be at increased risk of SF. CLINICAL RELEVANCE: Female runners need routine screening for risks associated with SF occurrence. As bone mineral density and bone turnover markers are not routinely assessed in this population, important risk factors may be missed.


Assuntos
Fraturas de Estresse/fisiopatologia , Corrida/fisiologia , Adulto , Biomarcadores/sangue , Distribuição da Gordura Corporal , Índice de Massa Corporal , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Feminino , Humanos , Menstruação , Pessoa de Meia-Idade , Condicionamento Físico Humano/fisiologia , Projetos Piloto , Estudos Prospectivos , Fatores de Risco , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
6.
Medicine (Baltimore) ; 99(26): e20864, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590789

RESUMO

Osteoporosis is defined as a metabolic skeletal disease characterized by a decrease of the bone mass per unit volume, caused by a variety of reasons. Increasing evidence indicate that the host inflammatory response was correlated with the occurrence and development of osteoporosis, and it has been recognized that T lymphocytes and B lymphocytes play a critical role in pathogenesis of inflammatory bone disease. Between January 2018 and December 2018, retrospective analysis of 487 patients (exclusion of patients with recent infections and hematologic disorders whose leukocyte counts or classifications are markedly abnormal) who underwent bone mineral density (BMD) examinations in Huzhou Central Hospital. The patients were divided into normal bone density group, osteopenia group, and osteoporosis group according to the T score of BMD in the left femoral neck, respectively. Statistics of the lymphocyte ratio and the monocyte ratio in the blood routine examination results during the same period were performed so as to make a comparison of the differences among the groups. The correlation of the lymphocyte ratio and monocyte ratio with the T score of BMD in the left femoral neck was also analyzed. The difference between neutrocyte ratio lymphocyte ratio and the monocyte ratio was statistically significant in both males and females among the normal bone density group, osteopenia group and osteoporosis group (P < .01 or P < .05). Inflammation plays an important role in the progression of osteoporosis. By monitoring these three indicators in blood routine examination, early intervention for osteoporosis may become possible.


Assuntos
Biomarcadores/análise , Células Sanguíneas/microbiologia , Osteoporose/diagnóstico , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Densidade Óssea/fisiologia , China , Correlação de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/sangue , Estudos Retrospectivos , Fatores de Risco
7.
Proc Natl Acad Sci U S A ; 117(25): 14386-14394, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513693

RESUMO

We report that two widely-used drugs for erectile dysfunction, tadalafil and vardenafil, trigger bone gain in mice through a combination of anabolic and antiresorptive actions on the skeleton. Both drugs were found to enhance osteoblastic bone formation in vivo using a unique gene footprint and to inhibit osteoclast formation. The target enzyme, phosphodiesterase 5A (PDE5A), was found to be expressed in mouse and human bone as well as in specific brain regions, namely the locus coeruleus, raphe pallidus, and paraventricular nucleus of the hypothalamus. Localization of PDE5A in sympathetic neurons was confirmed by coimmunolabeling with dopamine ß-hydroxylase, as well as by retrograde bone-brain tracing using a sympathetic nerve-specific pseudorabies virus, PRV152. Both drugs elicited an antianabolic sympathetic imprint in osteoblasts, but with net bone gain. Unlike in humans, in whom vardenafil is more potent than tadalafil, the relative potencies were reversed with respect to their osteoprotective actions in mice. Structural modeling revealed a higher binding energy of tadalafil to mouse PDE5A compared with vardenafil, due to steric clashes of vardenafil with a single methionine residue at position 806 in mouse PDE5A. Collectively, our findings suggest that a balance between peripheral and central actions of PDE5A inhibitors on bone formation together with their antiresorptive actions specify the osteoprotective action of PDE5A blockade.


Assuntos
Disfunção Erétil/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Inibidores da Fosfodiesterase 5/farmacologia , Envelhecimento/fisiologia , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Reposicionamento de Medicamentos , Disfunção Erétil/complicações , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais , Modelos Moleculares , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Osteoporose/complicações , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Inibidores da Fosfodiesterase 5/química , Inibidores da Fosfodiesterase 5/uso terapêutico , Cultura Primária de Células , Tadalafila/química , Tadalafila/farmacologia , Tadalafila/uso terapêutico , Dicloridrato de Vardenafila/química , Dicloridrato de Vardenafila/farmacologia , Dicloridrato de Vardenafila/uso terapêutico
8.
Internist (Berl) ; 61(6): 535-540, 2020 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-32458373

RESUMO

Vitamin D deficiency is widespread in geriatric patients. While vitamin D deficiency is prevalent in about 50% of healthy older adults, the prevalence in geriatric patients with hip fracture increases to over 80%. This is partly due to the fact that sunlight is unreliable as the main source of vitamin D. In addition to insufficient sun intensity from November to April, skin aging plays an important role; it causes a 4-fold reduction in the skin's own vitamin D production during sunshine exposure in older adults compared with younger people. Immobility and institutionalization are additional risk factors for vitamin D deficiency in geriatric patients. At the same time, vitamin D deficiency (< 20 ng/ml) increases parathyroid hormone levels and thus promotes bone loss and the risk of fracture. Severe vitamin D deficiency (< 10 ng/ml) may also lead to reversible muscle weakness resulting in an increased risk of falling. Since falls affect at least every second geriatric patient and hip fractures increase exponentially after the age of 75, the correction of vitamin D deficiency is an important medical and public health effort in these patients. Several randomized intervention trials, comparing 800-1000 IU vitamin D/day versus placebo or calcium, showed a significant reduction in falls and hip fractures in adults ≥65 years of age who had an increased risk of vitamin D deficiency and of falls or fractures. In geriatric patients, implementing vitamin D supplementation at this dosage is currently preferred. A bolus dose of over 24,000 IU/month should be avoided due to the increased risk of falls and fractures. These recommendations remain relevant after a critical review of the four most recent meta-analyses.


Assuntos
Osso e Ossos/efeitos dos fármacos , Fraturas Ósseas/prevenção & controle , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem , Acidentes por Quedas/prevenção & controle , Idoso , Densidade Óssea/fisiologia , Suplementos Nutricionais , Fraturas do Quadril/prevenção & controle , Humanos , Osteoporose/prevenção & controle , Vitamina D/sangue , Vitamina D/uso terapêutico , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/prevenção & controle
9.
Trop Doct ; 50(3): 228-232, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32419634

RESUMO

Osteoporosis is characterised by low bone mineral density (BMD) and is a significant public health problem in India. This cross-sectional study was done to assess the relationship between various anthropometric measures and BMD in 308 rural dwelling South Indian postmenopausal women. Anthropometric variables such as weight, body mass index (BMI), waist circumference (WC), hip circumference (HC) and neck circumference (NC) were measured. BMD was assessed by dual-energy X-ray absorptiometry (DXA) scan at the lumbar spine (LS) and femoral neck (NOF). The mean age ± SD of study participants was 60.7 ± 7.8 years. All anthropometric variables showed positive correlation with BMD at NOF and LS (P < 0.05). Weight showed the best correlation (r = 0.482 for NOF and 0.412 for LS; P < 0.001). On multivariate logistic regression, age and weight remained significant for predicting femoral neck osteoporosis while weight and WC were the best predictors for LS osteoporosis. These anthropometric measures may serve as surrogate markers for osteoporosis and thus be used to screen postmenopausal women for referral to a centre with fewer limited resources.


Assuntos
Assistência Ambulatorial/métodos , Osteoporose Pós-Menopausa/diagnóstico , Absorciometria de Fóton , Idoso , Antropometria , Pesos e Medidas Corporais , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiopatologia , Humanos , Índia/epidemiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/fisiopatologia , Fatores de Risco , População Rural
10.
Sports Health ; 12(5): 431-440, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442050

RESUMO

BACKGROUND: The positive association between physical fitness and bone structure has been widely investigated in children and adolescents, yet no studies have evaluated this influence in young children (ie, preschoolers). HYPOTHESIS: Fit children will present improved bone variables when compared with unfit children, and no sex-based differences will emerge in the sample. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: Handgrip strength, standing long jump (SLJ), speed/agility, balance, and cardiorespiratory fitness (CRF) were assessed using the Assessing FITness levels in PREschoolers (PREFIT) test battery in 92 children (50 boys; age range, 3-5 years). A peripheral quantitative computed tomography scan was performed at 38% of the length of the nondominant tibia. Cluster analysis from handgrip strength, SLJ, speed/agility, and CRF was developed to identify fitness groups. Bone variables were compared between sexes and between cluster groups. The association between individual physical fitness components and different bone variables was also tested. RESULTS: Three cluster groups emerged: fit (high values on all included physical fitness variables), strong (high strength values and low speed/agility and CRF), and unfit (low strength, speed/agility, and CRF). The fit group presented higher values than the strong and unfit groups for total and cortical bone mineral content, cortical area, and polar strength strain index (all P < 0.05). The fit group also presented a higher cortical thickness when compared with the unfit group (P < 0.05). Handgrip, SLJ, and speed/agility predicted all bone variables except for total and cortical volumetric bone mineral density. No differences were found for bone variables between sexes. CONCLUSION: The results suggest that global fitness in preschoolers is a key determinant for bone structure and strength but not volumetric bone mineral density. CLINICAL RELEVANCE: Physical fitness is a determinant for tibial bone mineral content, structure, and strength in very young children. Performing physical fitness tests could provide useful information related to bone health in preschoolers.


Assuntos
Osso e Ossos/anatomia & histologia , Osso e Ossos/fisiologia , Aptidão Física/fisiologia , Caracteres Sexuais , Densidade Óssea/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Pré-Escolar , Análise por Conglomerados , Estudos Transversais , Teste de Esforço/métodos , Feminino , Força da Mão/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Estudos Retrospectivos , Tíbia/fisiologia
11.
Br J Radiol ; 93(1111): 20190935, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32302222

RESUMO

OBJECTIVES: Transgender individuals submitted to hormone or surgical treatment may have alterations in their bone metabolism as these elements are important players in bone remodeling. We aimed to study bone mineral density (BMD) and body composition in transwomen undergoing cross-sex hormonal treatment (CSHT) from Brazil for over 3 years, comparing them with female and male controls. METHODS: 93 individuals (31 transwomen, 31 females and 31 males paired for age and body mass index) were studied for bone mass, and body composition by densitometry (by DXA). Epidemiological and clinical data were collected through direct questioning. RESULTS: Low bone mass (T score ≤2) was found in 12.9% of transwomen; in 3.2% of females and 3.3% of males. Transwomen individuals had lower spine Z score (0.26 ± 1.42 vs 0.50 ± 1.19) and femur Z score (-0.41 ± 0.95 vs 0.29 ± 1.04) than females. They had lower total femur Z score than males (-0.41 ± 0.95 vs 0.20 ± 0.83). Lean mass values correlated positively with total femur BMD (ρ = 0.40; 95% confidence interval = 0.009-0.68; p = 0.04) and BMD in femoral neck (ρ = 0.48; 95% confidence interval = 0.11-0.74; p = 0.01) but neither the type of therapy received nor the time that they were used, impacted bone mass. CONCLUSION: Low BMD is found frequently in transwomen and it is correlated with lean body mass. ADVANCES IN KNOWLEDGE: There are few studies of the effects of hormone therapy on the bones and muscles of transwomen. This study demonstrated that significant changes occur, and that the population studied needs greater care in musculoskeletal health.


Assuntos
Densidade Óssea/fisiologia , Transexualidade/fisiopatologia , Absorciometria de Fóton , Adulto , Antagonistas de Androgênios/uso terapêutico , Ossos do Braço/fisiologia , Composição Corporal/fisiologia , Distribuição da Gordura Corporal , Brasil , Estudos Transversais , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Feminino , Fêmur/fisiologia , Antebraço/fisiologia , Humanos , Masculino , Músculo Esquelético/anatomia & histologia
12.
J Nutr Health Aging ; 24(4): 388-397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32242206

RESUMO

OBJECTIVES: To determine the relationship between plant food consumption and bone mineral density (BMD) in a healthy population when age, gender, BMI and physical activity are accounted for. DESIGN: Cross-sectional study. SETTING: Participants were recruited from the Sydney Adventist hospital and the University of New South Wales, Sydney, Australia. PARTICIPANTS: 33 males and 40 females (total n=73) participated in this study. The mean age was 56.1 ± 8.5 years. All participants were non-diabetic and in general good health. MEASUREMENTS: A principle component analysis (PCA) was performed on 12 month self-report food intake data, gathered using the Cancer Council Victoria Dietary Questionnaire for Epidemiological Studies Version 2. Dual-energy X-ray absorptiometry was used to measure total BMD. Fasting plasma total protein, calcium and 25-Hydroxy Vitamin D levels were analysed by the Sydney Adventist Hospital pathology laboratory. Anthropometric measures were obtained using a standardized protocol. Self-reported physical activity levels were assessed using the International Physical Activity Questionnaire. RESULTS: The PCA revealed three principle components. These were termed 'Meat Based', 'Junk Food' and 'Plant Based.' After controlling for age, gender, physical activity and BMI, the Plant Based component correlated positively with BMD (p=0.054, R2=0.439) and T-score (p=0.053, R2=0.221). Using a similar model no association between the Meat Based component and BMD or T-score was found. However, when the Plant Based component was included the Meat Based component correlated positively with BMD (p=0.046, R2=0.474) and T-score (p=0.046, R2=0.279). There was no significant association between the Junk Food component and BMD or T-score. People in the third Plant (927 ± 339 vs 751 ± 255 g/day, p=0.025) and Meat Based (921 ± 270 vs 676 ± 241 g/day, p=0.002) tertile had higher calcium intakes than those in the first. People in the second Plant Based tertile had higher plasma Vitamin D levels than those in the first (63.5 ± 16.8 vs. 52.3 ± 22.1 nmol/L, p=0.053) while those in the third Junk Food tertile had lower levels than those in the first (52.4 ± 18.5 vs. 65.4 ± 19.8 nmol/L, p=0.027). No association between Plant Based tertiles and protein intake was observed, however those in the third Meat Based (99.7 ± 25.1 vs. 50.9 ± 13.8 g/day, p=0.000) and Junk Food (87.4 ± 30.7 vs. 56.6 ± 22.2 g/day, p=0.000) tertile had higher protein intake compared to those in the first tertile. CONCLUSION: In a healthy middle aged population with normal BMD, an increase in plant food consumption, either alone or in combination with a diet containing meat, is associated with improved bone mineralisation markers. This positive relationship is most likely due to the extensive range of micronutrients and phytochemicals packaged within plants.


Assuntos
Densidade Óssea/fisiologia , Plantas/química , Idoso , Estudos Transversais , Feminino , Humanos , Masculino
13.
Artigo em Inglês | MEDLINE | ID: mdl-32290133

RESUMO

Modern bioelectrical impedance analysis (BIA) provides a wide range of body composition estimates such as fat mass (FM), lean body mass (LBM), and body water, using specific algorithms. Assuming that the fat free mass (FFM) and LBM can be accurately estimated by the 8-electrode BIA analyzer (BIA8MF; InBody230, Biospace), the bone mineral content (BMC) may be calculated by subtracting the LBM from the FFM estimates based on the three-compartment (3C) model. In this cross-sectional study, 239 healthy Taiwanese adults (106 male and 133 female) aged 20-45 years were recruited for BIA and dual-energy X-ray absorptiometry (DXA) measurements of the whole body and body segments, with DXA as the reference. The results showed a high correlation between BIA8MF and DXA in estimating total and segmental LBM, FM and percentage body fat (r = 0.909-0.986, 0.757-0.964, and 0.837-0.936, respectively). For BMC estimates, moderate to high correlations (r = 0.425-0.829) between the two methods were noted. The percentage errors and pure errors for BMC estimates between the methods ranged from 33.9% to 93.0% and from 0.159 kg to 0.969 kg, respectively. This study validated that BIA8MF can accurately assesses LBM, FM and body fat percentage (BF%). However, the estimation of segmental BMC based on the difference between FFM and LBM in body segments may not be reliable by BIA8MF.


Assuntos
Absorciometria de Fóton , Composição Corporal , Densidade Óssea/fisiologia , Impedância Elétrica , Tecido Adiposo , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan
14.
Chemosphere ; 253: 126616, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283421

RESUMO

Excessive exposure to fluoride has been reported to affect bone mineral density (BMD). CALCA expression plays a critical part in bone formation. However, the role of CALCA in the association between fluoride and BMD is not known. We conducted a cross-sectional study and recruited 722 women in rural areas of Henan Province, China, to assess the relationship between fluoride exposure, CALCA methylation, and BMD. Urinary levels of fluoride, CALCA methylation, and BMD were measured by a fluoride ion-selective electrode, standalone ultrasound bone densitometer, and quantitative methylation-specific polymerases chain reaction, respectively. The association among fluoride exposure, CALCA methylation, and BMD was age-specific. Specifically, BMD was negatively correlated with methylation (ß: -0.008; 95% CI: -0.016, 0.000) and fluoride exposure (ß: -0.063; 95% CI: -0.129, -0.002) in women over 45 years and 50-54 years of age, respectively, whereas methylation was positively correlated with fluoride exposure (ß: 4.953; 95% CI: 1.162, 8.743) in women aged 40-44 years. Besides, increased BMD in women aged 45-49 years induced by the interactive effect of the highest methylation of CALCA exon 1 (tertile 3) and fluoride exposure was observed (P for interaction < 0.05). Our findings suggest an age-specific association between exposure to excessive fluoride, CALCA methylation, and BMD in a rural population of women in China. Notably, the susceptibility of BMD to fluoride exposure may be modified by CALCA methylation.


Assuntos
Densidade Óssea/fisiologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Exposição Ambiental/estatística & dados numéricos , Fluoretos/toxicidade , Absorciometria de Fóton , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático , Densidade Óssea/efeitos dos fármacos , China/epidemiologia , Estudos Transversais , Feminino , Fluoretos/análise , Humanos , Metilação , Pessoa de Meia-Idade , População Rural
15.
Clin J Sport Med ; 30(3): 245-250, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32341292

RESUMO

OBJECTIVE: To determine whether secondary amenorrhea during teenage years influences bone mineral density (BMD) in female athletes in their 20s. DESIGN: Original research. SETTING: Japan Institute of Sports Sciences. PARTICIPANTS: Two hundred ten elite female athletes older than 20 years were included in the study. MAIN OUTCOME MEASURES: Information on the participants' past (ie, during their teenage years) and current menstrual cycle, training time, history of stress fractures, and blood tests for hormones received was obtained. Bone mineral density of the lumbar spine was evaluated by dual-energy x-ray absorptiometry; low BMD was defined as a Z-score ≤-1. We investigated the correlation factors for low BMD in athletes in their 20s by univariable and multivariable logistic regression analysis. RESULTS: A total of 39 (18.6%) female athletes had low BMD. Secondary amenorrhea in their teens [odds ratio (OR), 7.11, 95% confidence interval (CI), 2.38-21.24; P < 0.001] and present body mass index (BMI) (OR, 0.56, 95% CI, 0.42-0.73; P < 0.001) were independent correlation factors for low BMD in the multivariable logistic regression analysis. The average Z-score for those with secondary amenorrhea in their teens and 20s, secondary amenorrhea in their 20s only, and regular menstruation was -1.56 ± 1.00, -0.45 ± 1.21, and 0.82 ± 1.11 g/cm, respectively. CONCLUSIONS: Secondary amenorrhea for at least 1 year during teenage years in female athletes and BMI at present was strongly associated with low BMD in their 20s.


Assuntos
Amenorreia/fisiopatologia , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/fisiopatologia , Esportes/fisiologia , Absorciometria de Fóton , Adolescente , Amenorreia/prevenção & controle , Índice de Massa Corporal , Doenças Ósseas Metabólicas/prevenção & controle , Estradiol/sangue , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , Hormônio Luteinizante/sangue , Ciclo Menstrual/fisiologia , Adulto Jovem
16.
Comput Methods Biomech Biomed Engin ; 23(8): 432-444, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32126825

RESUMO

Modeling the evolution of bone density is relevant for understanding, simulation and possible prediction of bone response to external and internal influences. In this work we present a formulation for the bone density evolution process that takes into account not only the commonly considered mechanical stimulus, but, as novelty, also the influence of the availability of nutrients and hormones, with its implementation pursued within the finite element method. A simple uni-axial extension test is used to illustrate and compare our novel model against the classical approach. The results of the proposed modified model are promising for application to real-life problems.


Assuntos
Remodelação Óssea/fisiologia , Disponibilidade Biológica , Fenômenos Biomecânicos , Densidade Óssea/fisiologia , Simulação por Computador , Fêmur/fisiologia , Análise de Elementos Finitos , Humanos , Úmero/fisiologia , Modelos Biológicos , Análise Numérica Assistida por Computador , Estresse Mecânico , Suporte de Carga
17.
Arch Osteoporos ; 15(1): 45, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32166587

RESUMO

The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men. Physical activity has the most significant effect on bone status especially in men. PURPOSE: The aim of the study was to assess the associations of bone mineral density and bone mass with physical activity levels, vitamin D, phosphorus, magnesium, total cholesterol and triglyceride concentration and body composition in young women and men. METHODS: One hundred subjects aged 19-24 years were included. Bone mineral density (BMD) in distal and proximal parts was evaluated by forearm densitometry. Body composition was analysed with the use of JAWON-Medical-x-scan. The following biochemical indicators were analysed: 25(OH) D and 1,25(OH)2D, magnesium, phosphorus, total cholesterol and triglycerides. Physical activity levels were assessed by interview. RESULTS: Significant correlations between BMD and physical activity, skeletal muscle mass and body fat percentage were revealed in men. Among women, considerably weaker correlations of BMD with body composition and physical activity were noted than in men. BMD in the distal part correlated only with lean body mass, soft lean mass and body fat percentage. The strongest relationship between physical activity and bone mineral status parameters was noted for BMD in men. In women, physical activity did not affect BMD. CONCLUSIONS: Physical activity has the most significant effect on bone status especially in men.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Exercício Físico/fisiologia , Estado Nutricional/fisiologia , Vitamina D/análogos & derivados , Absorciometria de Fóton , Índice de Massa Corporal , Colesterol/sangue , Feminino , Antebraço/diagnóstico por imagem , Antebraço/fisiopatologia , Humanos , Magnésio/sangue , Masculino , Fósforo/sangue , Triglicerídeos/sangue , Vitamina D/sangue , Adulto Jovem
18.
Arch Osteoporos ; 15(1): 47, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32173776

RESUMO

Association between strength of nonadjacent muscles and bone mineral density is unclear. We used data from the National Health and Nutrition Examination Survey to convince the effect of grip strength on femoral neck and lumbar spine mineral density in the general US population. This research can broaden the area of muscle-bone interaction. INTRODUCTION: Grip test measures the maximum isotonic strength of hand and forearm and is often used as an indicator of general muscle strength. Muscle has been shown to exert positive effects on bone health, and studies are needed to test whether grip strength can be associated with bone mineral density of nonadjacent bones. The aim of this study is to assess whether grip strength is an independent predictor for bone mineral density (BMD) of femoral neck and total lumbar spine in the general US population. METHODS: We used the data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014, and 1850 participants aged from 40 to 80 years old were included in the analysis. Grip strength was recorded as the largest reading of three efforts of one's dominant hand using a handgrip dynamometer. Femoral neck and lumbar spine BMDs were measured through Dual-energy X-ray absorptiometry (DXA) scan. Univariate and multivariate linear regression analyses were done to examine the association between grip strength and BMDs. RESULTS: After adjusting for age, ethnicity, body mass index (BMI), use of female hormones, smoking habit, drinking habit, family history of osteoporosis, use of calcium and vitamin D supplements, physical activity, serum calcium, and phosphorus levels, grip strength is associated with increased femoral neck and total lumbar spine BMDs in men (P < 0.001, P = 0.005), premenopausal women (P = 0.040, P = 0.014), and postmenopausal women (P = 0.016, P = 0.012). CONCLUSIONS: Our results suggest that (1) grip strength can be associated with BMD of nonadjacent bones, and (2) grip strength of dominant hand can be an indicator of BMD in the general US population across genders and menopausal status.


Assuntos
Densidade Óssea/fisiologia , Colo do Fêmur/fisiopatologia , Força da Mão/fisiologia , Vértebras Lombares/fisiopatologia , Força Muscular/fisiologia , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Exercício Físico , Feminino , Colo do Fêmur/diagnóstico por imagem , Antebraço/diagnóstico por imagem , Antebraço/fisiopatologia , Humanos , Modelos Lineares , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dinamômetro de Força Muscular , Inquéritos Nutricionais , Osteoporose/etiologia , Estados Unidos
19.
Arch Osteoporos ; 15(1): 48, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32185512

RESUMO

PURPOSE: To investigate the effects of dairy products on bone mineral density (BMD) in healthy postmenopausal women. METHODS: The EMBASE, Cochrane Library, Medline, and Web of Science databases were systematically searched for relevant studies. The pooled standardized mean difference (SMD) with its 95% confidence interval (CI) was used as the effect size. Subgroup analysis and Begg's test were conducted. RESULTS: Six studies with a total of 618 participants were included in the meta-analysis. Milk was the main dairy product used in the trials. There was a significant association between dairy product consumption and BMD of the lumbar spine (SMD 0.21, 95% CI 0.05-0.37, P = 0.009), femoral neck (SMD 0.36, 95% CI 0.19-0.53, P < 0.001), total hip (SMD 0.37, 95% CI 0.20-0.55, P < 0.001), and total body (SMD 0.58, 95% CI 0.39-0.77, P < 0.001). Subgroup analysis suggested that there was a positive effect of dairy product consumption on the BMD of the total hip starting from 12 months and the femoral neck starting from 18 months. There was also a positive association with the BMD in the four sites in people living in low-calcium intake countries. CONCLUSION: This meta-analysis provides evidence that dairy products can increase BMD in healthy postmenopausal women. Dairy product consumption should be considered an effective public health measure to prevent osteoporosis in postmenopausal women.


Assuntos
Densidade Óssea/fisiologia , Laticínios , Dieta/métodos , Osteoporose Pós-Menopausa/prevenção & controle , Pós-Menopausa/fisiologia , Conservadores da Densidade Óssea/farmacologia , Dieta/efeitos adversos , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiopatologia , Voluntários Saudáveis , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
J Nutr Health Aging ; 24(3): 277-281, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115608

RESUMO

OBJECTIVES: To clarify whether serum creatinine to cystatin C ratio (CCR), a marker of muscle mass and muscle function may be used as a simple marker of bone property. DESIGN: A cross-sectional analysis. SETTING: A general population-based observation study. PARTICIPANTS: 1,606 middle-aged to elderly (≥50 years, mean age: 66.9 ± 7.5 years old) men (n = 642) and post-menopausal women (n = 964). MEASUREMENT: Speed of sound (SOS) at the calcaneal bone was used as a surrogate marker of bone mineral density. The cross-sectional area of the muscle at the mid-thigh was measured using computed tomography. RESULTS: There was significant linear correlation between the quartiles of CCR and SOS (Q1: 1,495 ± 25, Q2: 1,499 ± 24, Q3: 1,507 ± 26, Q4: 1,511 ± 25 m/sec; P < 0.001) even in a sex-separated analysis. This association was independent of major covariates (Q1: ß = -0.126, P < 0.001; Q2: ß = -0.096, P = 0.001; Q3: ß = -0.022; P = 0.412, Q4: reference) and the mid-thigh muscle mass, while creatinine alone or eGFR did not show clear association with SOS. CONCLUSION: The CCR may be used as a simple marker of bone property independently of muscle mass in a general population with preserved renal function.


Assuntos
Densidade Óssea/fisiologia , Creatinina/sangue , Cistatina C/sangue , Idoso , Estudos Transversais , Feminino , Humanos , Masculino
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