Osteometabolic profile and bone mass in the transition phase: ethnic differences in Brazilians treated with somatropin during childhood

Abstract Objective: The main growth hormone action is to promote linear growth increasing protein synthesis stimulation and osteoblastic activity. Peak bone mass extends from adolescence to 30 years of age. Several factors may influence this acquisition and prevent fracture risk in adulthood, such as genetic potential, GH, ethnicity, and lifestyle factors. This study aims to compare bone mass and osteometabolic profile of white and Afro-descendant Brazilian adolescents in the transition phase, who were treated with human recombinant growth hormone in childhood. Methods: The authors selected 38 adolescents from the Transition Outpatient Clinic of the University of São Paulo. Lumbar spine and total body bone mineral density (BMD) and bone mineral content (BMC), serum calcium, 25-OH-vitamin D and bone markers were analyzed at the rhGH withdrawal. Results: The mean age was 16.8 ± 1.6 years. There were 21 Afro-descendant and 17 whites. Thirty-four percent of the sample presented vitamin D insufficiency, 66% inadequate calcium intake and 44.7% physical inactivity. The Afro-descendants showed a lower lumbar spine and total body Z scores than those of the whites (p = 0.04 and p = 0.03, respectively), as well as their mean body weight (p = 0.03). There were no differences in the remaining osteometabolic parameters. Conclusion: As most adolescents had vitamin D insufficiency, low calcium intake, and physical inactivity, calcium, and cholecalciferol supplementation and lifestyle changes should be encouraged. The Brazilian Afro-descendant may be a vulnerable group for low bone mass, requiring

Mineral bone disorder in children with chronic kidney disease: Data from the KNOW-Ped CKD (Korean cohort study for outcome in patients with pediatric chronic kidney disease) study.

Background: Children with chronic kidney disease (CKD) are at high risk of mineral bone disorder (MBD), which leads to fractures, growth retardation, and cardiovascular disease. We aimed to comprehensively understand the relationship between renal function and factors related to MBD and evaluate the prevalence and distribution characteristics of MBD, specifically among Korean patients from the KNOW-PedCKD cohort. Methods: From the baseline data of the KNOW-PedCKD cohort, we examined the prevalence and distribution of MBD in 431 Korean pediatric CKD patients, including the level of corrected total calcium, serum phosphate, serum alkaline phosphatase, serum intact parathyroid hormone (iPTH), fibroblast growth factor 23 (FGF-23), serum vitamin D, fractional excretion of phosphate (FEP), and bone densitometry Z-scores. Results: The median serum calcium level remained relatively normal regardless of the CKD stage. The levels of 1,25-dihydroxy vitamin D, urine calcium-to-creatinine ratio, and bone densitometry Z-score significantly decreased with advancing CKD stage, while those of serum phosphate, FGF-23, and FEP significantly increased with CKD stage. The prevalence of hyperphosphatemia (17.4%, 23.7%, and 41.2% from CKD stages 3b, 4, and 5, respectively) and hyperparathyroidism (37.3%, 57.4%, 55.3%, and 52.9% from CKD stages 3a, 3b, 4, and 5, respectively) significantly increased with the CKD stage. Prescriptions of medications, such as calcium supplements (39.1%, 42.1%, 82.4%), phosphate binders (39.1%, 43.4%, 82.4%), and active vitamin D (21.7%, 44.7%, and 64.7%) significantly increased with CKD stage 3b, 4, and 5, respectively. Conclusions: The results demonstrated the prevalence and relationship of abnormal mineral metabolism and bone growth according to CKD stage in Korean pediatric CKD patients for the first time.

Osteometabolic profile and bone mass in the transition phase: ethnic differences in Brazilians treated with somatropin during childhood.

OBJECTIVE: The main growth hormone action is to promote linear growth increasing protein synthesis stimulation and osteoblastic activity. Peak bone mass extends from adolescence to 30 years of age. Several factors may influence this acquisition and prevent fracture risk in adulthood, such as genetic potential, GH, ethnicity, and lifestyle factors. This study aims to compare bone mass and osteometabolic profile of white and Afro-descendant Brazilian adolescents in the transition phase, who were treated with human recombinant growth hormone in childhood. METHODS: The authors selected 38 adolescents from the Transition Outpatient Clinic of the University of São Paulo. Lumbar spine and total body bone mineral density (BMD) and bone mineral content (BMC), serum calcium, 25-OH-vitamin D and bone markers were analyzed at the rhGH withdrawal. RESULTS: The mean age was 16.8 ± 1.6 years. There were 21 Afro-descendant and 17 whites. Thirty-four percent of the sample presented vitamin D insufficiency, 66% inadequate calcium intake and 44.7% physical inactivity. The Afro-descendants showed a lower lumbar spine and total body Z scores than those of the whites (p = 0.04 and p = 0.03, respectively), as well as their mean body weight (p = 0.03). There were no differences in the remaining osteometabolic parameters. CONCLUSION: As most adolescents had vitamin D insufficiency, low calcium intake, and physical inactivity, calcium, and cholecalciferol supplementation and lifestyle changes should be encouraged. The Brazilian Afro-descendant may be a vulnerable group for low bone mass, requiring special strategies to increase bone accrual and body weight. More studies are necessary to compare ethnic differences in this population.

Parâmetros ósseos de codornas de corte suplementadas com diferentes níveis de vitamina A, de 15 a 35 dias de idade / [Parameters of bone of meat-type quail supplemented with different levels of vitamin A from 15 to 35 days of age]

Avaliou-se o efeito da utilização de níveis crescentes de vitamina A sobre os parâmetros ósseos de codornas de corte de 15 a 35 dias de idade. Foram utilizadas 1520 codornas, não sexadas, com peso médio inicial de 85±4,25g, distribuídas em um delineamento inteiramente ao acaso, totalizando oito tratamentos com cinco repetições e 38 codornas por unidade experimental. Os tratamentos consistiram de oito níveis de suplementação de vitamina A (0; 4.500; 6.000; 7.500; 9.000; 10.500; 12.000 e 13.500UI/kg da dieta). O período experimental foi de 15 a 35 dias de idade. Os ossos analisados apresentaram uma redução linear para o índice de Seedor, resistência óssea e teor de cinzas do fêmur e da tíbia de acordo com os níveis de suplementação de vitamina A. A suplementação de vitamina A para codornas de corte de 15 a 35 dias de idade mostrou resultados negativos para a qualidade óssea, com a necessidade de mais estudos sobre seu antagonismo com a vitamina D.(AU)

This study evaluated the effect of using increasing levels of vitamin A on bone parameters in meat-type quails from 15 to 35 days old. A total of 1520 unsexed quail with an average initial weight of 85g distributed in a completely randomized design, totaling eight treatments with five replicates and 38 quails per experimental unit were used. The treatments consisted of eight vitamin supplementation levels A (0; 4,500; 6,000; 7,500; 9,000; 10,500; 12,000 and 13,500IU / kg diet). The experimental period was 15 to 35 days of age. The bones analyzed showed a linear reduction to the Seedor index, bone strength and ash content of the femur and tibia according to vitamin supplementation levels Vitamin A supplementation for cutting quails from 15 to 35 days of age showed negative results for bone quality, with the need for more studies on its antagonism to vitamin D.(AU)

Combination of phytase and citric acid, but not phytase alone, ensures regular rates of growth and bone mineralization in quails under severe phosphorus restriction.

An experiment was conducted to evaluate the effects of phytase (PHY), alone or in combination with citric acid (CA), on growing Japanese quails under moderate and severe phosphorus (P) restriction. For this, 504 one-day-old female quails were distributed in a completely randomised design with seven treatments and six replications. Treatments consisted of the following diets: (a) positive control (PC): formulated according to quails nutritional requirements; (b) negative control 40% (NC40 ): PC with 40% less aP; (c) NC40 +PHY; (d) NC40 +PHY+CA; (e) negative control 65% (NC65 ): PC with 65% less aP; (f) NC65 +PHY; (g) NC65 +PHY+CA. Phytase and CA were included at 300 FTU/kg and 40 g/kg, respectively. Performance, bone mineralization and plasma mineral concentration were evaluated at day 35; calcium (Ca) and P metabolism, between days 36 and 39. No significant differences in performance, plasma Ca and P were detected between quails fed PC or NC40 ; however, NC40 decreased tibia ash (p < 0.01). Treatment NC65 impaired daily weight gain (p = 0.01), tibia ash (p < 0.01), and tibia optical densitometry (p = 0.03), as well as modified plasma Ca (p < 0.01) and P (p = 0.03) concentrations when compared to PC. Both NC40 and NC65 reduced P excretion (p < 0.01). Phytase alone restored tibia ash of NC40 quails to regular rates. Nevertheless, only PHY and CA combined returned plasma P, tibia ash, tibia optical densitometry, and daily weight gain of quails fed NC65 to similar values as those observed in PC. In conclusion, PHY alone suppresses the negative effects of moderate P restriction in growing Japanese quails, but fails in this task under severe P restriction. In such a situation, only the combination of PHY and CA ensures regular rates of growth and bone mineralization. This concept should be better explored by producers in order to take full advantage of the reduction in P excretion achieved by lowering dietary P concentrations.

Impact of Bariatric Surgery on Bone Mineral Density: Observational Study of 110 Patients Followed up in a Specialized Center for the Treatment of Obesity in France.

INTRODUCTION: Bariatric surgery is used to treat severe obesity. We aimed to investigate the incidence of clinically significant bone mineral density (BMD) loss at 6 and 12 months after bariatric surgery. METHODS: Observational study performed in a specialized center for the treatment of obesity at the University Hospital of Reims, France. Surface BMD was measured by dual x-ray absorptiometry (DEXA). A reduction of > 0.03 g/cm2 was considered clinically significant. RESULTS: A total of 110 patients were included. A clinically significant reduction in BMD was observed in 62.1% of patients at 6 months, and in 71.6% at 12 months after surgery. No case of osteoporosis was observed. There were four cases of osteopenia and one fracture post-surgery. BMD loss was related by univariate analysis to the reduction in body mass index (BMI) (p < 0.01), weight loss (p < 0.01), fat mass (p < 0.01), and lean mass (p < 0.01). Multivariable analysis found a significant association between the reduction in BMD and the excess weight loss percentage (odds ratio 1.11, 95% confidence interval (1.05-1.18), p < 0.001). CONCLUSION: There was a clinically significant reduction in BMD at 6 months after surgery in over 60% of patients undergoing bariatric surgery. BMD loss is persistent over time and predominantly situated at the femoral level, and strongly associated with weight loss. Systematic vitamin and calcium supplementation, as well as follow-up by DEXA scan seems appropriate. Systematic DEXA scan pre- and post-surgery, and annually thereafter until weight has stabilized seems appropriate.

De la osteología a la osteomiología: tres décadas de aportes originales continuos al análisis biomecánico osteomuscular / From osteology to osteo-myology: three decades of continuous, original contributions to musculoskeletal biomechanical analysis

En consonancia con la orientación tradicional de nuestras investigaciones, la Osteología está incorporando progresivamente el análisis estructural-biomecánico óseo y las interacciones músculo-esqueléticas. En este artículo se sintetizan los aportes originales del CEMFoC a la Osteología moderna en el terreno biomecánico en forma didáctica, para que el lector aprecie sus posibles aplicaciones clínicas. Los hallazgos aportaron evidencias sucesivas en apoyo de dos proposiciones fundamentales: a) los huesos deben interpretarse como estructuras resistivas, biológicamente servocontroladas ("Los huesos tienden siempre a mantener un factor de seguridad que permite al cuerpo trabajar normalmente sin fracturarse" ­ Paradigma de Utah) y b) los huesos interactúan con su entorno mecánico, determinado principalmente por las contracciones musculares, en forma subordinada al entorno metabólico ("Los huesos son lo que los músculos quieren que sean, siempre que las hormonas lo permitan"). Los avances producidos se refieren, tanto cronológica como didácticamente, al conocimiento osteológico en general y al desarrollo de recursos novedosos para el diagnóstico no invasivo de fragilidad ósea, para distinguir entre osteopenias y osteoporosis, y para discriminar entre sus etiologías 'mecánica' y 'sistémica'. Finalmente, el nuevo conocimiento se integra en la proposición de un algoritmo diagnóstico para osteopenias y osteoporosis. El espíritu general de la presentación destaca que la evaluación osteomuscular dinámicamente integrada genera un nuevo espacio de análisis personalizado de los pacientes para la atención de cualquier osteopatía fragilizante con criterio biomecánico. (AU)

In consonance with the traditional spirit of our studies, skeletal research is being progressively focused on the structural-biomechanical analysis of bone and the muscle-bone interactions. In this article, the CEMFoC's members summarize their original findings in bone biomechanics and their potential clinical applications. These findings provided evidence supporting two fundamental hypotheses, namely, A. bones constitute resistive structures, which are biologically servo-controlled ('Bones tend to maintain a safety factor which allows the body to function normally avoiding fractures' ­ the 'Utah paradigm'), and B. the interactions of bones with their mechanical environment mainly are determined by the contraction of local muscles - 'bone-muscle units'), and are subordinated to the control of the metabolic environment ('Bones are what muscles wish them to be, provided that hormones allow for it'). The achievements in the field are presented in a chronological and didactical sequence concerning the general knowledge in Osteology and the development of novel resources for non-invasive diagnosis of bone fragility, aiming to distinguish between osteopenias and osteoporosis and the 'mechanical' and 'metabolic' etiology of these conditions. Finally, the integrated new knowledge is presented as supporting for a proposed diagnostic algorithm for osteopenias and osteoporosis. In general terms, the article highlights the dynamic evaluation of the musculoskeletal system as a whole, opening a new diagnostic field for a personalized evaluation of the patients affected by a boneweakening disease, based on functional and biomechanical criteria. (AU)

Long-Term Dietary Intake of Chia Seed Is Associated with Increased Bone Mineral Content and Improved Hepatic and Intestinal Morphology in Sprague-Dawley Rats.

Chia seeds (Salvia hispanica) provide an unusually high content of α-linolenic acid with several potential health benefits, but few studies have examined the long-term intake of n-3 fatty acid-rich plant foods such as chia. In this work, we investigated some of the effects of a diet containing 10% chia seeds versus a conventional isocaloric diet for 10 and 13 months on body measurements, musculoskeletal system, the liver, and the intestines of 20 male Sprague-Dawley rats assigned into two groups. The n-6/n-3 ratios for the control and chia diets were 7.46 and 1.07, respectively. For the first 10 months of the diet, the body parameters and weights were similar, but at 13 months, the bone mineral content (BMC) of the chia-fed rats was significantly higher than that of the controls whether in total or proximal areas of the left tibia. Also, significant positive correlations were found between the age of the chia group and the bone mineral density, BMC, weight of the musculoskeletal system, final body weight, and skin weight. Liver and intestinal examinations showed improved morphology associated with lower lipid deposit in hepatocytes and increased intestinal muscle layers and crypt size in the chia group. This study provides new data suggesting the potential benefits associated with the long-term intake of chia seeds.

30years of DXA technology innovations.

As the successor of Dual Photon Absorptiometry (DPA), Dual X-ray Absorptiometry (DXA) has seen 30years of continuous technological innovations. Implementation of measures for standardization and quality assurance made DXA a reliable and clinically useful approach. Its use in clinical multicenter drug studies in osteoporosis lead to general acceptance as the standard technique of bone densitometry. The limitations of DXA are well established. As a measure of areal bone mineral density (aBMD) it depends on bone size and is biased by overlaying soft tissue and calcified structures. To some extent these errors can be reduced by estimation of bone depth and/or lateral imaging. DXA based aBMD can be supplemented by additional information obtainable from DXA scans: geometric indices such as hip axis length or complex models like 2-D finite element analysis have been developed and tested. Given the drastic improvement in image quality current DXA scans can be used for Vertebral Fracture Analysis (VFA) or grading of Abdominal Aortic Calcifications. A textural measure, Trabecular Bone Score (TBS) provides independent information on fracture risk. DXA devices can also be used for assessments beyond bone density. Periprosthetic aBMD changes can be monitored to study the mechanical fitting of bone implants. Total body composition measurements are increasingly being used in studies on nutrition, obesity, and sarcopenia. 30years after its inception DXA is the undisputed standard imaging technique for the assessment of osteoporotic fracture risk with new applications beyond bone densitometry adding to its value.

A simple and fast sampling method for chemical analyses and densitometry of bones through rib biopsies in cattle / Uma técnica simples e rápida de amostrar costelas para análises químicas e densitométricas por meio de biópsias em bovinos

We developed and evaluated a fast and simple method to obtain suitable bone samples for densitometry and chemical analysis through biopsies of the 12th rib of cattle. The postoperative recovery, dry matter intake (DMI) and average daily weight gain (ADG) was evaluated in 36 Nellore steers, nine of which were randomly selected for the control group and 27 others were rib biopsied. Every 30 days, rib biopsy was performed in nine steers, using a corded-electric pistol-grip drill coupled with a hole saw of a 3mm diameter pilot drill bit. This rib biopsy technique provided a suitable sample obtained in a fast way and allowed the surgeon to work alone with the animal slightly sedated and restrained in the crush. Dry matter intake (DMI) was not affected in biopsied animals. At the end of the experimental period (116 days) the average daily weight gain (ADG) was similar in the steers biopsied or not. The described method provided rib samples from cattle suitable for densitometry and chemical analysis of bone tissue without effects on health and performance. This information could greatly increase the accuracy for the diagnosis of phosphorus deficiency in cattle raised on pasture and allow the evaluation of bone metabolism in experimental animals.(AU)

No presente estudo foi desenvolvida uma técnica para se obter, de forma rápida e simples, amostras da 12a costela bovina por meio de biópsias. Avaliou-se a recuperação pós-operatória (durante 15 dias), o consumo de matéria seca (CMS) e o ganho de peso diário (GMD) de 36 novilhos Nelores, sendo nove animais controles e 27 submetidos à biópsia. A cada 30 dias biópsias de costelas foram realizadas em nove animais, usando uma furadeira elétrica acoplada a uma serra-copo com uma broca-guia de 3mm de diâmetro. Esta técnica de biópsia permitiu obter amostras ósseas de forma rápida, com o cirurgião operando sozinho e com os animais levemente sedados e em estação. Ao término do experimento (116 dias) o CMS e o GMD não foram afetados pelo procedimento cirúrgico. As amostras obtidas foram adequadas para exames radiográficos e subsequentes análises químicas. O conjunto de informações adquiridas com a técnica de biópsia de costelas permite aumentar a exatidão no diagnóstico da deficiência de fósforo em bovinos criados em pastagens e também realizar estudos sobre metabolismo ósseo em animais experimentais.(AU)

Physicians' attitudes to contemporary issues on osteoporosis management in Korea.

BACKGROUND: In management of osteoporosis, several concerns here have been raised. The current issue included the utilization of dual energy X-ray absorptiometry (DXA) and fracture-risk assessment (FRAX), screening of vitamin D deficiency and secondary osteoporosis, and long-term use of bisphosphonate and calcium supplements. There was no study on physicians' attitude on these current issues in Korea. Therefore, we investigated the physicians' attitude on these issues by survey. METHODS: We administered a 30-item questionnaire to all members of Korean Society for Bone and Mineral Research by email survey form. One hundred participants answered the questionnaire. The questionnaire included the questions about the physicians' attitude to current issues and the barriers to osteoporosis treatment in Korea. RESULTS: Most physicians used bone densitometry devices (99%) and, central DXA was the most accessible device (95%). Eighty-eight percent were aware of FRAX®, but among them, only 19.3% used it. The main reason for not using FRAX® was the lack of time in their proactive (76%). Screening for vitamin D status and secondary osteoporosis was performed by 59% and 52% of the respondents, respectively. The lack of awareness among patients and high costs of medication were perceived as the most important barriers to osteoporosis management in Korea. CONCLUSIONS: This study provides physicians' perspective to the current issue for diagnostic and treatment of osteoporosis in Korea. To further improve osteoporosis management, educational programs for patients and doctors, and the improvement of reimbursement system should be considered in Korea.

Physicians' Attitudes to Contemporary Issues on Osteoporosis Management in Korea

BACKGROUND: In management of osteoporosis, several concerns here have been raised. The current issue included the utilization of dual energy X-ray absorptiometry (DXA) and fracture-risk assessment (FRAX), screening of vitamin D deficiency and secondary osteoporosis, and long-term use of bisphosphonate and calcium supplements. There was no study on physicians' attitude on these current issues in Korea. Therefore, we investigated the physicians' attitude on these issues by survey. METHODS: We administered a 30-item questionnaire to all members of Korean Society for Bone and Mineral Research by email survey form. One hundred participants answered the questionnaire. The questionnaire included the questions about the physicians' attitude to current issues and the barriers to osteoporosis treatment in Korea. RESULTS: Most physicians used bone densitometry devices (99%) and, central DXA was the most accessible device (95%). Eighty-eight percent were aware of FRAX(R), but among them, only 19.3% used it. The main reason for not using FRAX(R) was the lack of time in their proactive (76%). Screening for vitamin D status and secondary osteoporosis was performed by 59% and 52% of the respondents, respectively. The lack of awareness among patients and high costs of medication were perceived as the most important barriers to osteoporosis management in Korea. CONCLUSIONS: This study provides physicians' perspective to the current issue for diagnostic and treatment of osteoporosis in Korea. To further improve osteoporosis management, educational programs for patients and doctors, and the improvement of reimbursement system should be considered in Korea.