Untangle the relationship of muscle mass and bone mineral content on handgrip strength: Results of ELSA-Brasil / Desvendando a relação entre massa muscular e conteúdo mineral ósseo na força de preensão palmar: Resultados do ELSA-Brasil

Abstract The study aims to investigate the independent association of muscle mass (MM) and bone mineral content (BMC) in the performance of the handgrip strength (HGS) test and whether there is effect modification by sex and age. In 12,491 participants from the ELSA-Brasil we estimated the associations between MM, BMC and HGS using linear regression models. All the analyses were performed for total population, also stratified for sex and age. For total population an interaction term was included between each explanatory variable of interest with sex and age to verify the presence of effect modification. We observed that the higher quintiles of MM and BMC were associated to an increasing in the mean of HGS compared to the first quintile, with greater magnitudes in men compared to women, also adults compared to elderly. When we estimated the independent effect of each exposure of interest, MM showed stronger effect in HGS in women, men and adults then BMC. In conclusion, we observed that higher amounts of MM and BMC are associated with higher HGS, regardless of sociodemographic characteristics, health conditions and lifestyle, with this effect being greater in men and adults.

Resumo O estudo tem como objetivo investigar a associação independente da massa muscular (MM) e conteúdo mineral ósseo (CMO) na realização do teste de força de preensão manual (FPM) e se há modificação do efeito por sexo e idade. Em 12.491 participantes do ELSA-Brasil estimamos as associações entre MM, CMO e FPM usando modelos de regressão linear. Todas as análises foram realizadas para a população total, também estratificada por sexo e idade. Para a população total foi incluído um termo de interação entre cada variável explicativa de interesse com sexo e idade para verificar a presença de modificação de efeito. Observamos que os maiores quintis de MM e BMC estiveram associados a um aumento na média da FPM em relação ao primeiro quintil, com maiores magnitudes em homens em relação a mulheres, também em adultos em relação a idosos. Quando estimamos o efeito independente de cada exposição de interesse, MM mostrou efeito mais forte na FPM em mulheres, homens e adultos do que BMC. Em conclusão, observamos que maiores quantidades de MM e BMC estão associadas a maior FPM, independentemente das características sociodemográficas, condições de saúde e estilo de vida, sendo esse efeito maior em homens e adultos.

Composição corporal de adolescentes pós-púberes avaliada pela absortometria radiológica de dupla energia e relações com a idade cronológica / Body composition in post-pubertal adolescents measured by dual-energy x-ray absorptiometry and relationship with chronological age

O objetivo do estudo foi analisar a composição corporal com utilização do DXA e correlacioná-la com a idade cronológica em adolescentes pós-púberes, de ambos os sexos. Participaram da pesquisa 46 adolescentes em fase pós-puberal, sendo 27 meninas (17,23±0,98) e 19 meninos (17,65±0,74) de ensino médio de uma escola estadual da Zona Sul da cidade do Rio de Janeiro. Foram realizadas uma anamnese, avaliação antropométrica e o DXA para avaliações. O teste U de Mann Whitney e o coeficiente de correlação de Spearman foram utilizados, adotando P<0,05 para significância. Verificou-se que as meninas apresentam composição corporal diferentedos meninos (P<0,05) e que com o aumento da idade elas tendem a diminuir o percentual de gordura, embora tenha sido observado um quantitativo alto de meninas com percentual de gordura elevado. Os meninos apresentaram uma tendência de aumento do percentual de gordura e da massa magra com o aumento da idade. As medidas de conteúdo e densidade mineral ósseo dentro da normalidade, com tendência de aumento com o avanço da idade cronológica. Conclui-se que os grupos masculino e feminino apresentaram comportamentos diferenciados quanto à composição corporal e os valores apresentados trazem mais um complemento à literatura a respeito de referências para a composição corporal, obtida com o DXA, em adolescentes pós-púberes.

The purpose of this study was to analyze body composition using DXA and correlate it with chronological age in post-pubertal adolescents of both genders. A total of 46 adolescents participated in the study, of which 27 were girls (17.23±0.98) and 19 boys (17.65±0.74) from a state school in the South District in the city of Rio de Janeiro. An anamnesis, anthropometric evaluation and DXA were performed for evaluations. The Mann-Whitney U test and the Spearman correlation coefficient were used, adopting P <0.05 for significance. Girls were found to have a different body composition than boys (P <0.05) and that, with increasing age, they tended to present a decrease in fat percentage, although in general a high number of girls presented a high fat level. The boys presented a tendency to increase the percentage of fat and lean mass with the increase of the age. Measurements of bone mineral content and density were considered as being within normality, with a tendency to increase with the advancing of the chronological age. Girls and boys present a different behavior regarding body composition and the values presented in this study bring an addition to the literature regarding body composition references through DXA in post-pubertal adolescents.

Study of prevalence of vitamin D deficiency in nephrotic syndrome

Background: Patients with nephrotic syndrome (NS) lose 25-hydroxyvitamin D in the urine and can have low blood levels of this metabolite. Corticosteroid therapy on long term basis can cause osteoporosis and affects the bone mineral content (BMC) and bone mineral density (BMD) in children. Hence this study was undertaken to study the prevalence of Vitamin D deficiency in children with Nephrotic syndrome.Methods: It is a time bound prospective hospital based observational study done at Department of Paediatrics, KIMS Hospital, Hubli. A detailed history and clinical examination including anthropometry was taken for cases of Nephrotic syndrome admitted to the hospital. 5ml venous blood was collected and sent for estimation of calcium (Ca), phosphorus (P), Alkaline phosphatase (ALP) and 25(OH) Vitamin D levels.Results: Mean age of onset of nephrotic syndrome was 4.6 years and median age at study entry was 7 years. Male to female ratio was 1.4:1. Vitamin D deficiency was present in 16(47.05%) children and insufficiency was present in 11(32.35%) children with nephrotic syndrome. Wasting was present in 11.76% and stunting was present in 50% of the children with nephrotic syndrome. There was no statistically significant difference of vitamin D levels with respect to sex and age group. Frequent relapsers had low levels of vitamin D levels as compared to 1st episode and infrequent relapsers. There was moderately significant positive correlation between serum calcium and vitamin D levels and negative correlation between phosphate levels and vitamin D levels.Conclusions: Vitamin D deficiency is common in children with nephrotic syndrome even after the remission of proteinuria.

Correlation between Serum Uric Acid and Bone Mineral Content in Healthy Women

BACKGROUND: Osteoporosis is a systemic skeletal disease characterized by reduced bone mineral density and skeletal microstructural abnormalities. We investigated the correlation between serum uric acid (SUA) levels and bone mineral content (BMC) values as a surrogate marker of bone health. Additionally, we assessed whether the correlation, if any, was evident even after classifying the study population into two groups based on a diagnosis of obesity in these individuals.METHODS: This study included 936 women who visited the healthcare centers that participated in this study. Fasting blood samples were obtained from all women to measure SUA, BMC of the lumbar spine was measured using dual-energy X-ray absorptiometry. We evaluated the correlation between SUA and BMC in obese and non-obese groups.RESULTS: SUA concentration and BMC were positively correlated (β=0.257, P=0.001); however, this correlation was significant only in the obese group (β=0.203, P=0.001).CONCLUSION: SUA concentration and BMC are positively correlated in women diagnosed obesity.

Experimental study of periostin promoting rapid distraction osteogenesis of the rabbit mandible / 口腔疾病防治

Objective @#To explore the promoting effect of periostin on rapid distraction osteogenesis of the rabbit mandible and provide experimental evidence for the clinical use of periostin to promote osteogenesis.@*Methods@#Twenty-four New Zealand male white rabbits underwent distraction osteogenesis, and after 3 days of retention, they were rapidly stretched at a stretch rate of 2 mm/d (total 5 d). The animals were randomly divided into group A and group B (12 per group). On the last day of the stretch, 0.5 mL of normal saline containing 40 μg of recombinant periostin was given to group B or an equal volume of normal saline was added to the control group (group A) for 8 days. At 4 weeks and 8 weeks post-stretch, 8 animals were randomly selected from each group to undergo a CT scan under general anesthesia. The bone mineral density and bone mineral content were detected by dual energy X-ray absorptiometry. Eight weeks post-stretch, all of the experimental animals were sacrificed. Six animals were randomly selected from each group for micro-CT and a histological examination, and the remaining animals were subjected to biomechanical tests. @*Results @#CT images showed that the new bone formation in the distraction space of group B was significantly better than that of group A at 4 and 8 weeks post-stretch. At 4 weeks and 8 weeks post-stretch, the bone mineral density in group B was (0.157 ± 0.016) g/cm 2 and (0.234 ± 0.023) g/cm 2, respectively, and the bone mineral content was (0.096 ± 0.010) g and (0.204 ± 0.017) g, respectively. The above four means were significantly higher in group B than in group A (P < 0.001). The micro-CT images and data suggest that the stretch gap microstructure of group B has more mature features. Histological experiments showed that the trabecular bone of group B was thick and mature, with few chondrocytes. The biomechanical test results showed that the biomechanical strength of the distraction gap in group B was (228.47 ± 39.98) N, which was 1.24 times that of group A (P = 0.045).@*Conclusion@# Interstitial use of periosteal protein in the distraction space of the mandible in rabbits can promote local new bone formation and mineralization.

Effects of a 20-week concurrent training program on bone metabolism in elderly women / Efecto de 20 semanas de entrenamiento concurrente sobre el metabolismo óseo de adultas mayores

The present study evaluated the effect of a 20-week concurrent training program on bone metabolism in elderly women. The sample consisted of 51 elderly women living in the municipality of Muriaé (MG), distributed into two groups: a concurrent training group (CTG = 25), with an average age of 69.44 ± 6.82 years, and a control group (CG = 26), with mean age of 68.30 ± 6.34 years. Biophysical parameters were determined based on weight, height and body mass index. Bone metabolism was assessed by collecting second-morning urine samples before and after intervention to analyze levels of the biochemical marker deoxypyridinoline (DPD), which quantifies bone resorption. Results: The results showed a post-intervention decline in DPD content in the GTC when compared to controls (p = 0.007) and an improvement in the variables weight, BMI and DPD between the GTC and GC (p = 0.000). Conclusion: Concurrent training was efficient in improving bone metabolism in the elderly population studied.

El presente estudio evaluó los efectos de 20 semanas de entrenamiento concurrente sobre el metabolismo óseo de adultas mayores. La muestra fue compuesta por 51 mujeres adultas mayores, residentes en el municipio de Muriaé (MG), voluntarias, distribuidas en dos grupos, un grupo participó en entrenamiento concurrente (GTC=25), con una edad media de 69,44±6,82 años y un grupo control (GC=26) con una media de 68,30±6,34 años. Los parámetros biofísicos se determinaron por medio del peso corporal, la estatura e índice de masa corporal. Para la evaluación del metabolismo óseo, se realizó la recolección de la orina matinal en el pre y post-test, utilizando como reactivo el marcador bioquímico de deoxipiridinolina (DPD) que cuantifica la reabsorción ósea. Los resultados mostraron una reducción en la concentración de DPD en el GTC cuando se compararon los grupos (p = 0,007) y la mejora de las variables, peso corporal, IMC y DPD entre el GTC y el GC en el post-test (p = 0,000). Se percibe que el entrenamiento concurrente, para las mujeres adultas mayores fue eficiente en la mejoría de las condiciones de salud del metabolismo óseo.

Effects of Different Landing Postures on Bone Mineral Density and Content During High-Impact Exercises / 医用生物力学

Objective To study effects of different types of high-impact exercises on the increment of bone mineral density (BMD) and bone mineral content (BMC) . Methods Thirty-nine male volunteers, including 13 hoopsters, 13 paratroopers, and 13 common college students as the control, were recruited and divided into two subgroups (subgroup 1:20-22 years old; subgroup 2:23-25 years old). Their BMDs and BMCs on calcaneus, first through fifth metatarsus, hip, and lumbar spine (L1-4) were evaluated. Results The BMC of calcaneus, the first and second metatarsals, total lumbar spine, and total hip in the hoopster group was significantly higher than that in the control group and paratrooper group. The hoopster group obtained statistically higher BMD at the lumbar spine, hip, and femoral neck than the other two groups. However, the BMCs and BMDs of the paratrooper group and control group had no significant differences at almost all measured anatomical locations. Conclusions BMC and BMD are not always in positive correlation with vertical ground reaction forces during normal exercises. Compared with parachuting training, playing basketball as a kind of variable load exercise can effectively increase BMC and BMD, and is more beneficial for reducing the risk of osteoporotic fracture.

Correlation analysis between lean body mass and bone mineral content in patients with type 2 diabetes mellitus / 中国综合临床

Objective To investigate the relationship between lean mass and bone mineral content (BMC)and bone mineral density(BMD)in normal and increased BMI overweight and obese patients with type 2 diabetes mellitus.Methods Seventy-two patients with type 2 diabetes mellitus treated in the First Affiliated Hospital of Nantong from June 2014 to August 2016 were selected in this study.According to body mass index (BMI),the patients were divided into the normal group(BMI<24 kg/m2)and the obese diabetic group(BMI=24 kg/m2).The systolic blood pressure(SBP),diastolic blood pressure(DBP),body mass index(BMI),waist circumference(WC),fasting blood glucose(FBG),glycosylated haemoglobin(HbA1c),blood lipids(TC,TG, HDL-C,LDL-C),alanine aminotransferase(ALT),creatinine(Cre),calcium(Ca),phosphorus(P)and serum 25 hydroxyvitamin D(25OHD)were measured.The bone mineral density(BMD),bone mineral content (BMC),body fat percentage(BF%),lean body mass(LBM),fat mass(FM),and the ratio of male fat to female fat(A/G)were measured by dual energy X-ray(DXA).The above indicators were statistically analyzed.Results 25OHD in the obese diabetic group was(17.1+ 12.6)μg/L,lower than that in the normal diabetic group((23.8±8.2)μg/L)(P<0.05),but BMI,WC,BMD,BMC,%BF,FM in the obese diabetic group(BMI:(27.8±2.1)kg/m2,WC:(96.8±7.9)cm,BMD:(1.12±0.14)g/cm2,BMC:(2.47±0.38) kg,fat and fat percentage:(1.18±0.23))were higher than those in the normal group(BMI:(22.3±1.7)kg/m2,WC:(84.5 + 7.9)cm,BMD:(0.93 ± 0.13)g/cm2,BMC:(2.02 ± 0.28)kg,fat and fat percentage:(2.02±0.28))(P<0.05).There was a significant positive correlation between LBM and BMC in different parts of the body(R=0.37,0.37,0.35,0.43,P<0.05,P<0.001).The ratio of BMI and A/G was also positively correlated with BMC and BMD(r=0.38,0.31,0.28,0.33,0.27,0.25,0.23,0.37,P<0.05,P<0.001).There was a negative correlation between body fat percentage and BMC,BMD(r=-0.30,-0.27,-0.25,-0.33,P<0.05,P<0.001).After correction of age,sex,BMI and 25OHD,multiple linear regression analysis was used to indicate that LBM was a strong predictor of BMC(regression coefficient=0.210,P=0.001).Conclusion In patients with type 2 diabetes mellitus,BMC and BMD increased significantly in patients with elevated BMC,and lean body weight was a strong influencing factor for BMI.

Densidad ósea volumétrica vertebral obtenida sin fantoma en estudios de rutina de tomografía computarizada de abdomen: correlación con los valores medidos por densitometría ósea areal por rayos X / Phantom-less volumetric vertebral density obtained from routine abdominal ct studies: correlation with data obtained by DXA

La densidad mineral ósea (DMO) por tomografía computarizada cuantitativa (QCT) mide con exactitud y precisión de corto plazo la densidad volumétrica (DMOv) de secciones axiales de los cuerpos vertebrales lumbares valiéndose de un fantoma de calibración. Existe evidencia de que la densitometría por TC sin fantoma convirtiendo las unidades Hounsfield en g/cm3 aplicando un coeficiente específico para cada equipo, presenta muy alta correlación con la DMO por QCT y que es confiable para evaluar la densidad ósea vertebral. Apoyándonos en ello, correlacionamos DMO y CMO estimados a partir de estudios de TC con los obtenidos por DXA. Se incluyeron 28 mujeres (edad: 63,4±10,3 años, rango: 37-85) que habían realizado una TC de abdomen y previamente una DMO en un lapso previo no mayor de 6 meses. Se midieron: 1) TC: DMOv promedio integral (trabecular + cortical) en un corte axial medio vertebral de 10 mm de espesor y el área en cm2 . Se multiplicó la densidad por el área, obteniendo un valor equivalente al CMO de la sección (CMO-TC) y 2) DXA: se consideraron la DMOa y CMO en una RI de 10 mm de altura a nivel del centro de la vértebra L3. Las correlaciones entre los parámetros homólogos obtenidos por ambos métodos fueron significativas: resultó superior para CMO [DMOv vs. DMOa r: 0,67 (p=0,005) y CMO-TC vs. CMO-DXA r: 0,75 (p=0,00063)]. El estudio complementa los ya existentes y abre la posibilidad de utilizar estudios de rutina de TC de abdomen para evaluar la densidad ósea, para lo cual deberán establecerse valores de referencia sexo y edad específicos. (AU)

Conventional quantitative computed tomography (QCT) uses a calibration phantom scanned simultaneously with the anatomical region of interest and measures bone density accurately and with short-term high precision. Evidence supports that phantom-less volumetric BMD highly correlates with QCT BMD and is a reliable method for assessing bone density of vertebral bodies. Assessment of BMD in routine abdominal CT scans has been investigated in recent years. The aim of the study was to correlate BMD and bone mineral content (BMC) obtained from CT studies with data obtained by DXA. Twenty eight women (age 63.4±10.3 years old, range: 37-85) who underwent abdominal CT for different reasons and DXA measurements within 6 months were included. A simple manual region of interest (RI) which delineated the edge of the vertebral body was applied to L3. We measured 1) CT: Volumetric integral density (BMDv) -trabecular and cortical bone- of the axial section and area (A) in cm2 . Density was multiplied by area to obtain a value equivalent to BMC. 2) DXA: BMD and BMC in a RI of 10 mm height in the middle of L3. All parameters obtained by CT correlated significantly with the corresponding to DXA : BMDv vs BMDa r: 0.67 (p=0.005) y BMC-CT vs BMC-DXA: r: 0.75 (p=0.00063). This study complements previous reports and opens the possibility of using routine abdominal CT studies to assess bone density. For that purpose reference values (age and gender) must be established. (AU)

Densitometric analysis of the human ulna / Análisis densitométrico de la ulna humana

This study describes the distribution of the normal bone mass in the mature human ulna, as knowledge of distribution may provide information to orthopaedic surgeons for the treatment of such fractures while advancing the understanding of the responses of osteosynthesis elements during bone repair. A random sample of 41 dry ulnas was studied with a DXA system using a Norland XR-26 densitometer. Two projections were performed, lateral and antero-posterior. In both projections five regions of interest (ROI) were selected: proximal (ROI 1), proximal-intermediate (ROI 2), intermediate (ROI 3), distal-intermediate (ROI 4) and distal (ROI 5). All statistical calculations were performed using Stat graphics Plus (version 5.1) and SPSS (version 15.0). Bone mineral density (BMD) and bone mineral content (BMC) were calculated. Paired data were analysed using parametric Student t-Test to compare BMD and BMC in every region in both projections. DXA show that the higher BMD is in the proximal-intermediate region (ROI 2). The higher BMC is found in the proximal region (ROI 1). Lower BMD and BMC are found in the distal region (ROI 5). The total BMD shows significant statistical differences (p0.001), which indicates the heterogeneous nature of the distribution of bone mass in the studied bone. Bone densitometry, measured by the DXA technique, is useful for assessing trabecular architecture of the human ulna.

Este estudio describe la distribución de la masa ósea de la ulna humana madura. Su conocimiento de distribución puede proporcionar información a cirujanos ortopédicos para el tratamiento de fracturas a la vez que se avanza en la comprensión de las respuestas de los elementos de osteosíntesis durante la reparación ósea. Se utilizó una muestra de 41 ulnas secas, que se estudiaron mediante absorciometría dual fotónica de rayos-X (DXA) con un densitómetro Norland XR-26. Se emplearon dos proyecciones: anteroposterior y lateral. En ambas proyecciones se seleccionaron cinco regiones de interés: proximal (ROI 1), intermedio-proximal (ROI 2), intermedia (ROI 3), intermedio-distal (ROI 4) y distal (ROI 5). Los cálculos estadísticos se realizaron con los programas Stat Graphics Plus (versión 5.1) y SPSS (versión 15.0). Se obtuvieron los valores medios y desviaciones estándar de la densidad mineral ósea (DMO) y el contenido mineral óseo (CMO) en cada una de las regiones de interés y en ambas proyecciones. Se compararon los valores medios de todas las regiones usando la prueba t de Student para muestras pareadas. La mayor DMO se encontró en la región intermedio-proximal (ROI 2) y en ambas proyecciones, mientras que la región que presentaba el mayor CMO fue la región proximal (ROI 1). Los valores más bajos, tanto de CMO como de DMO, en las dos posiciones del examen, correspondieron con la región distal (ROI 5). Al comparar cada una de las regiones con todas las restantes, encontramos que la DMO y el CMO muestran diferencias muy significativas (p0,001), lo que indica la naturaleza heterogénea de la distribución de la masa ósea en la ulna. La densitometría ósea mediante DXA es útil para establecer un esquema de construcción estructural de la ulna humana.

Effects of combined intervention of isoflavone supplementation and exercise on bone metabolism in growing rats / 한국영양학회지

PURPOSE: This study examined the effects of combined intervention of isoflavones and exercise on bone mineral density, bone mineral content, and biochemical bone markers. METHODS: Forty rats were divided into four groups; Control, Isoflavones (IF), Isoflavones + Running (IFR), and Isoflavones + Swimming (IFS). All of the rats in this study were fed an experimental diet and deionized water ad libitum for nine weeks. Bone mineral density (BMD) and bone mineral content (BMC) were estimated using PIXImus (GE Lunar Co, Wisconsin.) in spine and femur nine weeks after feeding or training. RESULTS: The combined intervention did not affect weight gain, mean food intake, or food efficiency ratio. The serum concentrations of ALP and osteocalcin were not significantly different by combined intervention. The urinary DPD crosslinks values were not significantly different by combined intervention. There were no significant differences in serum PTH, calcitonin, and estradiol among all groups. Spine BMD, spine BMC and femur BMC were not significantly different by combined intervention. However, femur BMD was significantly higher in the IFR group than in the control group. Compared with the control group, spine BMD, spine BMC, and femur BMD per weight were markedly increased in the isoflavones supplementation and combined intervention group. In addition, femur BMC per weight was significantly higher in the IFS group than in the control group. Compared with the isoflavones supplemented group, BMD and BMC were not significantly different by combined intervention. CONCLUSION: It can be concluded that isoflavones supplementation or combined intervention of isoflavone and exercise had a beneficial effect on spine and femur peak bone mass in growing female rats.

Supplementation of calcium and phosphorus in parenteral nutrition for extremely low-birth-weight infants / 中华临床营养杂志

Objective To investigate the usefulness of calcium and phosphorus supplementation in parenteral nutrition for extremely low-birth-weight (ELBW) infants.Methods According to the inclusion criteria,66 ELBW infants hospitalized after birth in neonatal ward of Tongji Hospital from June 2009 to December 2012 were divided into three groups with random number table:28 infants in the first group were treated with parenteral nutrition without calcium and phosphorus supplementation,21 infants in the second group were treated with parenteral nutrition with calcium supplementation only,and 17 infants in the third group was treated with parenteral nutrition with calcium and phosphorus supplementation.The blood levels of ionic calcium,blood phosphorus,and urine calcium and creatinine were determined once a week (total of 4 times).The speed of sound (SOS) was detected for shin bones by quantitative ultrasound at the date of admitting and the end of 4weeks.Results After administrations of supplementation,the blood levels of ionic calcium in the second group were significantly higher than those in the first group [on the 14th day,(1.82 ± 0.35) mmol/L vs.(1.14 ±0.47) mmol/L,t=5.800,P=0.005;onthe21stday,(1.77±0.45) mmol/Lvs.(1.07±0.43) mmol/L,t=5.492,P=0.004; on the 28th day,(1.61±0.58) mmol/Lvs.(0.92±0.44) mmol/L,t=4.556,P=0.025].The blood levels of ionic calcium in the third group were also significantly higher than those in the first group [on the 14th day,(1.55 ± 0.30) mmol/L vs.(1.14 ± 0.47) mmol/L,t =3.570,P =0.001 ; on the 21st day,(1.58 ±0.38) mmol/L vs.(1.07 ±0.43) mmol/L,t =4.151,P=0.000; on the 28th day,(1.55 ±0.35) mmol/L vs.(0.92 ±0.44) mmol/L,t =5.302,P =0.003].The blood levels of phosphorus were significantly elevated in the third group compared with those in the first group [on the 14th day,(1.86 ±0.10) mmol/L vs.(1.65 ±0.17) mmol/L,t=5.217,P=0.012; on the21st day,(1.88 ±0.14) mmol/Lvs.(1.61 ±0.13) mmol/L,t =6.442,P=0.003; on the 28th day,(1.89 ±0.15) mmol/L vs.(1.58 ±0.14) mmol/L,t =6.891,P =0.000] and the second group [on the 14th day,(1.86 ± 0.10) mmol/L vs.(1.53 ±0.15) mmol/L,t =8.100,P=0.000; on 21st day,(1.88 ±0.14) mmo/Lvs.(1.57 ±0.14) mmol/L,t =6.787,P =0.000; on the 28th day,(1.89 ± 0.15) mmol/L vs.(1.62 ± 0.18) mmol/L,t =5.043,P =0.000].The calcium-to-phosphorus ratios markedly increased in the second group compared with those in the first group (on the 14th day,0.69 ±0.18 vs.0.33 ±0.14,t =7.601,P =0.000; on the 21st day,0.66±0.16 vs.0.37 ±0.14,t =6.62,P=0.001 ; on the 28th day,0.62 ±0.15 vs.0.39 ±0.12,t =5.776,P =0.005) while declined in the third group (on the 14th day,0.14 ± 0.10 vs.0.33 ± 0.14,t =5.294,P =0.010; on the 21st day,0.13 ± 0.12 vs.0.37 ± 0.14,t =6.102,P =0.002; on the 28th day,0.12 ± 0.11 vs.0.39 ± 0.12,t =7.711,P =0.000).The third group showed significantly increased SOS values than those in the first and second groups [(381 ± 87) m/s vs.(135 ± 87) m/s,t =9.815,P =0.000;(381 ±87) m/s vs.(146 ±68) m/s,t =9.774,P=0.000].Conclusions Proper supplementation of calcium and phosphorus via parenteral nutrition can achieve increased bone mineral contents and stable blood ionic calcium and phosphorus levels,and avoid hypercalciuria in ELBW infants.PN therapy with calcium and phosphorus supplementation in ELBW infants needs further studies.

The effect of bench-stepping exercise training on BMD, BMC and bone metabolism in menopausal women / 体力科学

Since the effect of the submaximal aerobic exercise on bone had been controversial, the aim of this study was to elucidate the effect of the bench step (BS), that seemed to deliver higher mechanical load on bone than any other aerobic exercises, on the total bone mineral content (BMC) and the bone metabolism of menopausal women. Sixteen menopausal women (65 ± 9 years old) as the exercise group (ExG) and 28 pre-menopausal women (43 ± 3 years old) as the control group (CG) were studied. ExG carried out BS training with the exercise intensity at lactate threshold (LT) for 21 weeks. In ExG, BMC was measured by dual energy X-ray absorptiometry (DXA) at one year before the intervention (A year before), pre-intervention (Pre) and post-intervention (Post). Serum osteocalcin (OC) as the marker of bone formation and serum type I collagen cross-linked N-telopeptide (NTx) as the marker of bone absorption at Pre, 11th week of the intervention and Post. In CG, BMC was measured annually without the intervention. In ExG, OC was not changed, but NTx was significantly decreased by intervention (<i>p</i><0.05). The decreased amount of annual change in BMC between a year before and Pre (T1) was significantly higher compared to that between Pre and Post (T2) (<i>p</i><0.01) and CG (<i>p</i><0.001). There was no significant difference between T2 and CG. In conclusion, BS with LT could prevent decreasing BMC in menopausal women, and maintain the same level of BMC in pre-menopausal women by suppressing the bone absorption.

Calcium supplementation, bone mineral density and bone mineral content. Predictors of bone mass changes in adolescent mothers during the 6-month postpartum period

We determined the effect of calcium supplementation on bone mineral density (BMD) and bone mineral content (BMC) and identified predictors of bone mass changes in adolescent mothers 6 months postpartum. A prospective, analytical, clinical study was performed in adolescent mothers (≤19 years old; n=37) from La Plata, Argentina. At 15 days postpartum, mothers were randomly assigned into one of two groups and started with calcium supplementation; one group received dairy products (932 mg Ca; n=19) and the other calcium citrate tablets (1000 mg calcium/day; n=18). Weight, height and dietary intake were measured and BMD was determined by DEXA at 15 days (baseline) and 6 months postpartum. BMC, total body BMD and BMD were assessed in lumbar spine, femoral neck, trochanter and total hip. Regression models were used to identify the relationship of total body BMD and BMC with independent variables (calcium supplementation, months of lactation, weight at 6 months, percent weight change, lean mass at 6 months, percent lean mass change, total calcium intake). Results showed that changes in BMD and BMC at the different sites were similar in both groups, and changes in percent body weight and total calcium intake were the main predictive factors. In conclusion, the effect of calcium was similar with either form of supplementation, i.e., dairy products or tablets, and changes in percent body weight and total calcium intake were predictors of total body BMD and BMC changes.

Suplementación con calcio, densidad mineral ósea y contenido mineral óseo. Predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. El objetivo del estudio fue determinar el efecto de dos formas de suplementare calcio sobre la densidad mineral ósea (DMO) y el contenido mineral óseo (CMO), e identificar predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. Se realizó un estudio prospectivo, analítico y clínico en madres adolescentes (≤19 años; n=37) de la ciudad de La Plata, Argentina. A partir de los 15 días postparto, las adolescentes fueron distribuidas al azar en 2 grupos y comenzaron con la suplementación con calcio; un grupo recibió productos lácteos (932 mg Ca; n=19) y el otro citrato de calcio (1000 mg calcio/día; n=18). Se midió peso, altura y consumo de alimentos y se determinó la DMO por DEXA a los 15 días (línea de base) y a los 6 meses postparto. También se determinó CMO, DMO corporal total y DMO de columna lumbar, cuello femoral, trocánter y cadera total. Se usaron modelos de regresión para identificar relaciones entre DMO corporal total y CMO con variables independientes (tipo de suplementación, meses de lactancia, peso a los 6 meses, porcentaje de cambio de peso, masa magra a los 6 meses, porcentaje de cambio de masa magra, consumo total de calcio). Los resultados muestran que los cambios en DMO y CMO en los distintos sitios fueron similares en ambos grupos, y que los cambios en los porcentajes de peso corporal e ingesta total de calcio fueron los principales factores predictivos. En conclusión, el efecto del calcio fue similar tanto con productos lácteos como con comprimidos. Los cambios porcentuales en peso corporal e ingesta total de calcio resultaron factores predictivos de los cambios de la DMO corporal total y el CMO.

Conteúdo e densidade mineral óssea de adolescentes do sexo feminino / Bone mineral density and content in adolescent girls

O presente estudo teve como objetivo caracterizar o conteúdo mineral ósseo (CMO) e a densidade mineral óssea (DMO) de adolescentes do sexo feminino de acordo com a faixa etária e o estágio de maturação sexual. A amostra desse estudo foi composta por 329 meninas com idades entre 10 e 20 anos. Foram avaliados o peso corporal, estatura, índice de massa corporal, estágio de maturação sexual, a raça, o consumo diário de cálcio e o tempo dispendido em atividades físicas de intensidades moderada a vigorosa por semana (AFMV). A densidade e o conteúdo mineral ósseo da coluna lombar e do colo do fêmur foram avaliados pela densitometria óssea. As diferenças da DMO e do CMO, de acordo com a idade e a maturação sexual, foram avaliadas por uma análise de variância One-way ANOVA com o teste post-hoc de Tukey (p<0,05). O consumo diário de cálcio reportado pelas adolescentes é inadequado, pois representa uma variação de 26 a 47 por cento do que é recomendado. Por outro lado, o tempo dispendido em AFMV, por semana, foi muito superior ao mínimo recomendado, em todas as idades. Ocorreram diferenças significativas tanto na DMO quanto no CMO das adolescentes no período dos 10 e 14 anos de idade. Além disso, os valores de DMO da coluna lombar e do colo do fêmur das adolescentes pós-púberes foram 58 por cento e 31 por cento maiores,respectivamente, quando comparados com os seus correspondentes nas adolescentes pré-púberes.

The aim of the present study was to characterize bone mineral density (BMD) and content (BMC) in Brazilian adolescent girls according to age and pubertal stage. A total of 329 girls ranging in age from 10 to 20 years participated in this study. Body weight, height, body mass index, pubertal stage, race, daily calcium intake, and time spent per week performing moderate- to vigorous-intensity physical activity (MVPA) were evaluated. Lumbar spine and femoral neck BMD and BMC were assessed by dual-energy x-ray absorptiometry. One-way ANOVA with Tukey post-hoc test was used to identify differences in bone mass between ages and pubertal stages (p£0.05). The daily calcium intake reported by the adolescents was inadequate, corresponding to only 26-47 percent of the recommended allowance (1,300 mg/day). On the other hand, weekly MVPA was higher than that recommended for adolescents. Significant differences in BMD and BMC were observed for girls aged 10-14 years. In addition, lumbar spine and femoral neck BMD was 58 and 31 percent higher in postpubertal girls, respectively, when compared to prepubertal adolescents.

Effects of isoflavone supplementation on the bone mineral density of growing female rats

This study was focused on whether or not isoflavones affect the increase in bone mineral density of growing females. Female Sprague-Dawley rats (60 +/- 5 g) were randomly assigned to two groups and provided control diets (control group) or isoflavone-supplemented diet (IF group, 57.8 mg isoflavones/100 g diet) for 9 weeks in growing female rats. Measurements of Bone Mineral Density (BMD) and Bone Mineral Content (BMC) on the experimental animals were executed in the 3rd, 6th, 9th weeks. In result, there was no significant difference in spine BMD between the isoflavones supplemented group and the control group. But, the IF group tended to have higher BMD than the control group in between 3 and 9 experimental weeks, and the striking difference could be shown in the 6th week of feeding. In case of femur BMD, the effects of added isoflavones appeared in the 6th week of feeding, and it became intensified in the 9th week of feeding to the extent that the BMD in the IF group was significantly higher than that of the control group (p<0.05). In conclusion, isoflavone supplementation increased spine BMD per weight in the 6th week of feeding, and affected the increase of femur BMD in the 9th week. The result of the experiment implies that it affects positively the formation of spine and femur BMD of growing female rats. The study also suggests that the effects of isoflavone on the pattern of BMD formation might differ from the parts of bones.

Densidade mineral óssea de crianças e adolescentes com hipotireoidismo congênito / Bone mineral density of children and adolescents with congenital hypothyroidism

Realizou-se estudo transversal com 60 pacientes (9,9 ± 1,8 anos) com hipotireoidismo congênito (HC) (grupo A): 40 meninas (23 pré-púberes) e 20 meninos (18 pré-púberes), com grupo controle (grupo B) constituído por 28 indivíduos (10,4 ± 2,1 anos): 18 meninas (8 pré-púberes) e 10 meninos (9 pré-púberes). OBJETIVOS: Avaliar a densidade (DMO) e o conteúdo mineral ósseo (CMO) e correlacioná-los com idade cronológica e óssea (IO), sexo, maturação sexual, dose de l-T4, TSH, TT4, FT4, e etiologia do HC. IO, DMO e CMO de corpo total (DXA) foram obtidos dos 2 grupos; TSH, TT4 e FT4, apenas dos pacientes. DMO foi menor no grupo A (0,795 ± 0,075 g/cm² vs. 0,832 ± 0,092; p = 0,04) e maior nas meninas púberes do que nas pré-púberes (p = 0,004). Não houve diferença significativa de DMO e CMO quanto ao sexo e etiologia do HC. Nosso estudo mostra que a DMO foi significativamente menor no grupo com HC, diferente dos dados da literatura.

A cross sectional study was made on 60 patients (9.9 ± 1.8 yr-old) with congenital hypothyroidism (CH) (group A): 40 girls (23 prepubertal) and 20 boys (18 prepubertal). Control group (group B) was constituted of 28 healthy children (10.4 ± 2.1 yr-old): 18 girls (8 prepubertal) and 10 boys (9 prepubertal). AIMS: To evaluate bone mineral density (BMD) and content (BMC) and to correlate them with chronological and bone age (BA), sex, sexual maturation, l-T4 dose, TSH, TT4, FT4, and CH etiology. BA, total body BMD, and BMC (DXA) were obtained of both groups. TSH, TT4, and FT4 were measured in patients only. BMD was lower in group A (0.795 ± 0.075 g/cm² vs. 0.832 ± 0.092; p = 0.04) and higher in pubertal than in prepubertal girls (p = 0.004). There was no significant difference between BMD and BMC related to sex and CH etiology. Our data demonstrated that BMD was significantly lower in children with CH, different from what has been published in the literature.

Relationship between Progression of Knee Osteoarthritis and Ratio of Fat,Lean or Bone Mineral Content / 中国康复理论与实践

@#Objective To study the relationship between knee osteoarthritis progression and the ration of fat,lean,or bone mineral content(BMC).Methods 36 joints of knee with osteoarthritis in 31 women were divided into two groups according to the knee joint space,joint space narrowing group and non-narrowing group.The body mass index(BMI)was calculated.The X-ray(weight bearing)of knee joint was taken.The fat,lean,BMC and mass of leg were detected with the dual energy X-ray absorptiometry(DXA).Results There was no distinct difference between sides and age distribution for the tested groups(P>0.05).The BMI and fat/mass ratio of leg in the joint space narrowing group were obviously higher than that of the non-narrowing group(P<0.05),while the lean/mass ratio of leg in the joint space narrowing group was distinctly lower than that of the non-narrowing group(P<0.05).Conclusion The deterioration of the female knee osteoarthritis can be mainly attributed to the increase of the BMI and fat/mass ratio as well as the decrease of the lean/mass ratio of leg.

Factors Associated with Changes in Bone Mineral Content among Girls in Early Pubertal Age

The study was conducted to investigate the factors associated with bone mineral content ( BMC) changes among early pubertal aged girls. Two hundred and thirty girls between 9 to 11 years of age participated in four surveys over 2 year period. During each survey, dietary intakes were collected with 3-day food records, BMC of left leg's calcaneus were measured by PIXI ( Lunar Ltd.) and body composition was measured by bioimpedance method ( Inbody 3.0 Biospace Co. Ltd, Seoul, Korea) . Mean values of BMC increased in consecutive measurements - 1.48 g, 1.54 g, 1.61 g and 1.66 g. The change of BMC between the first and last measurements was significantly positively correlated with % body fat, negatively correlated with BMC at the baseline ( p < 0.05) . Change of BMC was also significantly positively correlated with % change of lean mass and mineral mass between the first and last measurements. Nutrient intakes during the study period were calculated as mean daily intakes from all surveys. Mean daily intakes of Vit. C and Vit. B6 were positively and isoflavone intake was negatively correlated with changes of BMC ( p < 0.05) . In stepwise regression of BMC change with body composition and nutrient intakes, baseline values of BMC, weight, BMI and age, % change of mineral mass during the study period, mean intakes of isoflavone, Vit. B6, protein, carotene and zinc were significant explanatory variables ( R 2 = 0.38, p < .001, F = 32.39) . The results imply that the change of BMC among early pubertal aged girls are associated with some body composition and intakes of certain nutrients.

The Effects of Level of Isoflavones Supplementation on Bone Mineral Density in Growing Female Rats

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in growing female rats. The effects of level of isoflavones supplementation on bone mineral density (BMD) and bone mineral content (BMC) were inspected in this study. Forty-five rats divided into three groups: Casein, 1/2IF, IF. The serum and urine concentrations of calcium and phosphorus were determined. BMD and BMC were estimated by using PIXImus (GE Lunar Co, Wisconsin.) in spine and femur on 3, 6, 9 weeks after feeding. This study of results were as follows: The isoflavones supplementation level did not affect weight gain, mean food intake and food efficiency ratio. The serum concentration of calcium, phosphorus were not significantly different by different level of isoflavones supplementation. The urinary calcium and phosphorus excretion were not significantly different, too. Spine and femur BMD, BMC were not significantly increased by different level of isoflavones supplementation on 3 and 6 weeks after feeding. Spine BMD and spine BMC per weight, femur BMC per weight were significantly increased in the groups 1/2IF and IF at the ninth week after feeding, but there was no significant difference by different level of isoflavones supplementation. Spine BMD per weight and femur BMD per weight were significantly higher in the group of IF than in the group of Casein and 1/2IF at the ninth week after feeding. These results suggest that the group of IF with rich isoflavones supplementation was effective to the increase of BMD spine and femur in growing female rats, respectively.