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1.
Int J Integr Care ; 24(2): 22, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855027

RESUMO

Introduction: This paper describes 'Project 8', a campaign that aims to reduce glycated haemoglobin (HbA1c) to 8% or more among patients with diabetes mellitus, utilising healthcare professionals and local community residents and focusing on education and support. The study is based in Uonuma-a small rural city in Japan with a declining population and an increased number of older people. Description: 'Project 8' began in Uonuma's Koide Hospital in 2008. The Uonuma School for Community Health and Social Care was established in 2011 with the cooperation of a clinic's general practitioner. Medical students, trainees, doctors, and health care professionals have been holding 'open schools' (daytime lectures) and 'night schools' (evening lectures) to educate the community residents about various health issues. Through repeated lectures, the residents have been made aware of lifestyle-related diseases, including diabetes, and the meaning of 'Project 8'. Discussion: Over the last decade, the hospital's campaign has expanded within the community, showing a statistically significant reduction of diabetic patients with HbA1c ≥ 8%, which successfully deferred the start of dialysis for many of them. Conclusion: Well-integrated community care requires interprofessional education, collaborative practice, and the participation of community residents in health education.

2.
JBMR Plus ; 8(7): ziae070, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38868596

RESUMO

The International Society of Bone Morphometry (ISBM) is dedicated to advancing research, education, and clinical practice for osteoporosis and other bone disorders by developing and improving tools for the quantitative imaging and analysis of bone. Its initial core mission was to promote the proper use of morphometric techniques in bone research and to educate and train clinicians and basic scientists in bone morphometry. This article chronicles the evolution of the ISBM and the history and development of bone morphometric techniques for the past 50-years, starting with workshops on bone morphometry in 1973, to the formal incorporation of the ISBM in 1996, to today. We also provide a framework and vision for the coming decades. This effort was led by ISBM presidents Dr Erica L. Scheller (2022-2024) and Dr Thomas J. Wronski (2009-2012) in collaboration with all other living ISBM presidents. Though the underlying techniques and questions have changed over time, the need for standardization of established tools and discovery of novel approaches for bone morphometry remains a constant. The ISBM fulfills this need by providing a forum for the exchange of ideas, with a philosophy that encourages the open discussion of pitfalls and challenges among clinicians, scientists, and industry partners. This facilitates the rapid development and adaptation of tools to meet emerging demands within the field of bone health at a high level.

3.
Injury ; 55(6): 111452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461102

RESUMO

BACKGROUND: In April 2022, a new reimbursement scheme for hip fracture was implemented by the Japanese health ministry. Japan is one of the world's most aged societies, facing a significant, rapidly growing burden of osteoporosis and fragility fractures. The incidence of hip fractures is projected to increase from 240,000 in 2020 to 320,000 by 2040. In 2015, Fragility Fracture Network-Japan (FFN-Japan) was formally established as a nonprofit organization in order to create the optimal fragility fracture care system in Japan. METHODS: FFN-Japan launched the Japan National Hip Fracture Database (JNHFD) in 2017, initially with only eight participating hospitals across Japan. The number of patients enrolled from May 2017 to the end of 2020 in the JNHFD from the 16 hospitals registered the patients during this period with amounting to 4271 patients in total. FFN-Japan invited officials from the Ministry of Health, Labor and Welfare (MHLW) to participate in round table meetings to discuss the data collected in the JNHFD and to consider opportunities for nationwide improvement in hip fracture care. RESULTS: The proportion of patients who underwent surgery within 36 h of arrival at hospital was 48.1% in 2018, 58.6% in 2019, and 44.9% in 2020 indicating the delay of surgery. Regarding secondary fracture prevention, initiation of osteoporosis treatment during the in-patients was 60.2% in 2018, 54.0% in 2019, and 64.5% in 2020 indicating the inadequate post fracture care. In April 2022, the Central Social Insurance Medical Council of the Japanese MHLW announced a new reimbursement scheme for hip fracture care including two key components: Early surgery (within 48 h from injury) and Secondary fracture prevention immediately after fracture. DISCUSSION: The new reimbursement scheme of hip fracture care in Japan will catalyze and underpin major improvements on acute multidisciplinary care and post-fracture care with secondary fracture prevention. FFN-Japan played a key role on these policy changes to the health system by means the close collaboration and ongoing communication with the government. CONCLUSION: Within five years of establishment of the JNHFD, FFN-Japan in collaboration with visionary leaders from the Japanese government have successfully achieved a major reform of the Japanese health system's reimbursement of hip fracture care. This reform has laid the foundation for transformation of management of this debilitating and life-threatening injury that currently afflicts almost a quarter of a million older Japanese citizens each year.


Assuntos
Bases de Dados Factuais , Fraturas do Quadril , Humanos , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Fraturas do Quadril/economia , Japão/epidemiologia , Idoso , Masculino , Feminino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/economia , Fraturas por Osteoporose/terapia , Osteoporose/epidemiologia , Osteoporose/terapia , Idoso de 80 Anos ou mais
4.
J Bone Miner Metab ; 42(2): 214-222, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38329506

RESUMO

INTRODUCTION: Vitamin D deficiency causes osteoporosis, bone mineralization disorders, and osteomalacia. Osteomalacia is diagnosed using blood biochemical tests, clinical symptoms, and imaging; however, accurate detection of mineralization disorders requires tissue observation. We investigated the prevalence of bone mineralization disorders and their relationship with serum 25-hydroxyvitamin D (25OHD) levels in patients with untreated osteoporosis with femoral neck fractures. MATERIALS AND METHODS: A non-demineralized specimen was prepared from the femoral head removed during surgery in 65 patients. Bone histomorphometry of cancerous bone in the femoral head center was conducted. Osteoid volume per bone volume (OV/BV) and osteoid thickness (O.Th) were measured as indicators of mineralization disorder. RESULTS: The mean serum 25OHD level (11.9 ± 5.7 ng/mL) was in the deficiency range (< 12 ng/mL). There were no clinically diagnosed cases of osteomalacia (OV/BV > 10% and O.Th > 12.5 µm); however, one case of mineralization disorder, considered histologically pre-osteomalacia (OV/BV > 5% and O.Th < 12.5 µm), was observed (OB/BV, 17.6%; O.Th, 12.3 µm). Excluding this case, those with severe (25OHD < 12 ng/mL, at risk of osteomalacia; n = 39) and non-severe deficiency (25OHD ≥ 12 ng/mL; n = 25) did not significantly differ in OV/BV (%; 0.77 ± 0.54 vs. 0.69 ± 0.38, p = 0.484) or O.Th (µm; 5.32 ± 1.04 vs. 5.13 ± 0.78, p = 0.410). Further, 25OHD and OV/BV were not significantly correlated (R = - 0.124, p = 0.327). CONCLUSION: This is the first study in the twenty-first century to examine serum 25OHD concentrations and bone mineralization disorders in Japanese patients with osteoporosis. The results indicate that vitamin D deficiency does not necessarily cause bone mineralization disorders and rarely leads to osteomalacia.


Assuntos
Fraturas do Colo Femoral , Osteomalacia , Osteoporose , Deficiência de Vitamina D , Vitamina D/análogos & derivados , Humanos , Estudos Transversais , Osteomalacia/patologia , Densidade Óssea , Calcifediol , Deficiência de Vitamina D/complicações , Cabeça do Fêmur/patologia
5.
J Bone Miner Res ; 38(11): 1603-1611, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37548352

RESUMO

Romosozumab treatment reduces the rate of hip fractures and increases hip bone density, increasing bone formation by inhibiting sclerostin protein. We studied the normal pattern of bone formation and osteocyte expression in the human proximal femur because it is relevant to both antisclerostin treatment effects and fracture. Having visualized and quantified buds of new bone formation in trabeculae, we hypothesized that they would coincide with areas of (a) higher mechanical stress and (b) low sclerostin expression by osteocytes. In patients with hip fracture, we visualized each bud of active modeling-based formation (forming minimodeling structure [FMiS]) in trabecular cores taken from different parts of the femoral head. Trabecular bone structure was also measured with high-resolution imaging. More buds of new bone formation (by volume) were present in the higher stress superomedial zone (FMiS density, N.FMiS/T.Ar) than lower stress superolateral (p < 0.05), and inferomedial (p < 0.001) regions. There were fewer sclerostin expressing osteocytes close to or within FMiS. FMiS density correlated with greater amount, thickness, number, and connectivity of trabeculae (bone volume BV/TV, r = 0.65, p < 0.0001; bone surface BS/TV, r = 0.47, p < 0.01; trabecular thickness Tb.Th, r = 0.55, p < 0.001; trabecular number Tb.N, r = 0.47, p < 0.01; and connectivity density Conn.D, r = 0.40, p < 0.05) and lower trabecular separation (Tb.Sp, r = -0.56, p < 0.001). These results demonstrate modeling-based bone formation in femoral trabeculae from patients with hip fracture as a potential therapeutic target to enhance bone structure. © 2023 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Fraturas do Quadril , Osteócitos , Humanos , Densidade Óssea , Cabeça do Fêmur , Fraturas do Quadril/diagnóstico por imagem , Osteogênese
6.
J Neurosurg Spine ; 36(3): 429-439, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653987

RESUMO

OBJECTIVE: Teriparatide (TPTD) is a potent promoter of early-stage osteogenesis and may be a useful adjuvant therapy to reduce complications related to bone fragility in spinal surgery patients with osteoporosis. However, effective neoadjuvant TPTD therapy regimens remain poorly understood. This study aimed to examine the effect of preoperative TPTD administration on cancellous bone with bone histomorphometry and to clarify the timing of preoperative TPTD administration for patients with spinal fusion and osteoporosis. METHODS: In this longitudinal multicenter study, 57 patients with spinal fusion and osteoporosis, who consented to undergo iliac biopsy, were allocated to the following treatment groups: neoadjuvant TPTD therapy group (n = 42) and no neoadjuvant therapy (NTC) group (n = 15). Patients in the TPTD group were categorized into subgroups on the basis of duration of preoperative TPTD administration, as follows: 1 month (n = 9), 2 months (n = 8), 3 months (n = 9), 4 months (n = 7), and 6 months (n = 9). All patient samples were preoperatively double labeled with tetracycline, and iliac biopsies were performed during spinal fusion surgery. Histomorphometric analyses were performed on nondecalcified, thin-sliced specimens. Specimens were classified on the basis of TPTD administration duration and subsequently compared with those of the NTC group. Postoperative complications and Oswestry Disability Index scores were evaluated at 1 and 2 years after surgery. RESULTS: There were no demographic differences between groups. Mineralizing surface/bone surface, a key parameter of dynamic bone formation, started to increase after 1 month of TPTD administration; this increase became significant after 3 months of administration and peaked at 4 months, with a 6-fold increase relative to that of the NTC group. The patients who received preoperative TPTD for 3 months or more had superior clinical results in terms of the osteoporotic complication rate and Oswestry Disability Index scores, except for bisphosphonate-pretreated patients. CONCLUSIONS: When considering neoadjuvant TPTD therapy, the authors recommend at least 3 months of preoperative administration to provide a more substantial anabolic effect from the early postoperative stage.

7.
Bone Rep ; 14: 101091, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34036125

RESUMO

An 83 year-old Japanese woman complained of left lateral thigh pain following a low-energy fall 4 months prior to admission. She had been treated for osteoporosis with Risedronate and Alfacalcidol for the previous five years. She was diagnosed with an atypical femoral fracture (AFF) according to the American Society for Bone and Mineral Research (ASBMR) Task Force revised criteria. Radiographs revealed cortical thickening and a transverse radiolucent fracture line in the lateral cortex of the shaft. MRI showed a high intensity signal on the T2WI image 1 cm long in the lateral cortex. The patient had normal levels of bone resorption and formation biomarkers except for low 25(OH) Vitamin D. Double fluorescent labeling was done preoperatively. Due to significant bowing, a corrective osteotomy and intramedullary nailing were performed, and the resected bone wedge was analyzed by bone histomorphometry. Three ground sections of the lateral cortex at the fracture site showed many and large pores, with or without tetracycline labeling. Histomorphometric assessment was done on intracortical pores, classified by a novel criteria, only to assess size of the pores to know prolonged osteoclastic activity and its characteristics of inner surfaces to assess whether bone formation has been occurring or not in labeling period in remodeling cycle, and coalition of multi-pores. Increased size with widespread variation of pores suggested prolonged osteoclastic activity in the reversal/resorptive phase. Bone labeling showed lamellar bone on the endocortical surface. We hypothesize that the case had developed from a regional disturbance of osteonal remodeling in the lateral cortex, in which accumulated microcracks might have initiated a resorption process resulting in resorption cavities, i.e., pores, which became larger due to prolonged activity of secondary osteoclasts. Various sized pores could form lamellar bone, still forming at the time of biopsy, some had formed lamellar bone, but stopped to form before labeling and not to start to form at all, probably due to incomplete coupling. Endocortical lamellar bone might had started to resorbed to smooth off endocortical surface, followed by formation of lamellar bone. The endocortical bone formation was assessed and its formation period is about 2.7 years. A finite element analysis using preoperative CT data revealed high tensile stresses on the lateral aspect of the femur. Histomorphometric results suggest that there might be more pores in the tensile area than the compressive area. These findings may subsequently connect accumulation of microcracks, an increase of size and number of pores and coalition and subsequent fracture in the lateral cortex.

8.
Drug Discov Ther ; 14(5): 218-225, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33116039

RESUMO

Recently, it has been suggested that glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1), which play important roles in the homeostasis of glucose metabolism, could be involved in the regulation of bone metabolism. Inhibitors of dipeptidyl peptidase 4 (DPP-4), an enzyme that degrades GIP and GLP-1, are widely used clinically as a therapeutic agent for diabetes. However, the effects of DPP-4 inhibitors on bone metabolism remain unclear. In this study, we investigated the effects of linagliptin, a DPP-4 inhibitor, on bone fragility induced by type 2 diabetes mellitus (T2DM). Non-diabetic mice were used as controls, and T2DM mice were administered linagliptin orally on a daily basis for 12 weeks. In T2DM mice, decreased bone mineral density was observed in the lower limb bones along with low serum osteocalcin levels and high serum tartrate-resistant acid phosphatase-5b (TRAP) levels. In contrast, the decreased serum osteocalcin levels and increased serum TRAP levels observed in T2DM mice were significantly suppressed after the administration of linagliptin 30 mg/kg. Bone histomorphometric analysis revealed a reduced osteoid volume and osteoblast surface with an increase in the eroded surface and number of osteoclasts in T2DM mice. This decreased bone formation and increased bone resorption observed in the T2DM mice were suppressed and trabecular bone volume increased following the administration of 30 mg/kg linagliptin. Collectively, these findings suggest that linagliptin may improve the microstructure of trabecular bone by inhibiting both a decrease in bone formation and an increase in bone resorption induced by T2DM.


Assuntos
Osso e Ossos/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Linagliptina/farmacologia , Administração Oral , Animais , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/anormalidades , Osso e Ossos/metabolismo , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Inibidores da Dipeptidil Peptidase IV/administração & dosagem , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Polipeptídeo Inibidor Gástrico/metabolismo , Polipeptídeo Inibidor Gástrico/farmacologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Linagliptina/administração & dosagem , Linagliptina/uso terapêutico , Masculino , Camundongos , Camundongos Obesos , Osteocalcina/sangue , Osteocalcina/efeitos dos fármacos , Fosfatase Ácida Resistente a Tartarato/sangue , Fosfatase Ácida Resistente a Tartarato/efeitos dos fármacos
9.
Drug Discov Ther ; 14(2): 77-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378649

RESUMO

Tacrolimus, a calcineurin inhibitor, affects bone metabolism and increases the risk of fracture due to marked bone loss. Bisphosphonates increase the bone mineral density (BMD) in osteoporosis patients. Menatetrenone has less positive effects on BMD but reduces the risk of fracture by improving bone quality. In this study, we investigated the effectiveness of the combined administration of risedronate and menatetrenone against bone loss induced by tacrolimus. Wistar rats were divided into four groups: [1] control, [2] tacrolimus at 1.5 mg/kg, [3] tacrolimus + risedronate at 1.0 mg/kg, and [4] tacrolimus + risedronate + menatetrenone at 20 mg/kg. After the drugs were administered for 4 weeks, bone histomorphometric analysis was performed and bone strength was evaluated using a three point bending method. BMD was measured using quantitative computed tomography. Tacrolimus significantly reduced the BMD and strength properties of the lower limb bones. These tacrolimusinduced decreases were suppressed by risedronate treatment. The combined administration of risedronate and menatetrenone more significantly improved bone strength properties than risedronate alone. Bone histomorphometric analysis revealed a significant increase in bone resorption with tacrolimus. Risedronate alone significantly suppressed the tacrolimus-induced increase in bone resorption but simultaneously reduced bone formation. On the other hand, the combined administration of risedronate and menatetrenone suppressed the tacrolimus-induced increase in bone resorption, in addition to the significant risedronate-induced decrease in bone formation. This study suggests that the combined administration of risedronate and menatetrenone improves bone strength in tacrolimus-treated rats by preventing and ameliorating the risedronate-induced suppression of bone formation.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Imunossupressores/efeitos adversos , Ácido Risedrônico/uso terapêutico , Tacrolimo/efeitos adversos , Vitamina K 2/análogos & derivados , Animais , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/induzido quimicamente , Quimioterapia Combinada , Fêmur/efeitos dos fármacos , Fêmur/fisiologia , Masculino , Osteogênese/efeitos dos fármacos , Ratos Wistar , Tíbia/efeitos dos fármacos , Tíbia/fisiologia , Vitamina K 2/uso terapêutico
10.
Eur Spine J ; 28(6): 1314-1321, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30783802

RESUMO

PURPOSE: To determine whether posterior implant removal prevents stress-shielding-induced vertebral osteopenia within the posterior fusion area in surgically treated patients with adolescent idiopathic scoliosis (AIS). METHODS: Eighteen patients with major thoracic AIS (mean age, 43.3 years; range, 32-56 years; mean follow-up, 28.8 years, range, 20-39 years) who underwent posterior spinal fusion (PSF) alone between 1973 and 1994 were included. Participants were divided into implant removal (group R, n = 10, mean interval until implant removal, 50 months) and implant non-removal groups (group NR, n = 8). Bone mineral density was evaluated using the Hounsfield units (HU) of the computed tomography image of the full spine. The HU values of the UIV-1 (one level below the uppermost instrumented vertebra), apex, LIV+1 (one level above the lowermost instrumented vertebra), and LIV-1 (one level below the lowermost instrumented vertebra; as a standard value) were obtained. Stress-shielding-induced osteopenia was assessed as the UIV-1/LIV-1, apex/LIV-1, and LIV+1/LIV-1 HU ratios (× 100). RESULTS: Overall (median, 25th-75th percentile), the apex (144.7, 108.6-176.0) and LIV+1 (159.4, 129.7-172.3) demonstrated lower HU values than LIV-1 (180.3, 149.2-200.2) (both comparisons, p < .05). Comparison of groups R and NR showed no significant differences in the scoliosis correction rate, bone mineral density of the proximal femur, the HU absolute values of all investigated vertebrae, or in the HU ratios of the investigated vertebrae to LIV-1. CONCLUSION: Instrumented PSF causes stress-shielding-induced osteopenia of the vertebral body within the fusion area in adulthood, which cannot be prevented by posterior implant removal, probably due to firm fusion mass formation. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Doenças Ósseas Metabólicas/etiologia , Parafusos Ósseos/efeitos adversos , Escoliose/cirurgia , Fusão Vertebral/efeitos adversos , Adolescente , Adulto , Densidade Óssea , Doenças Ósseas Metabólicas/fisiopatologia , Doenças Ósseas Metabólicas/prevenção & controle , Remoção de Dispositivo , Feminino , Fêmur/fisiopatologia , Seguimentos , Humanos , Cifose/diagnóstico por imagem , Cifose/cirurgia , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X , Adulto Jovem
11.
Am J Med Genet A ; 176(11): 2331-2341, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30195269

RESUMO

Musculocontractural Ehlers-Danlos syndrome caused by mutations in CHST14 (mcEDS-CHST14) is a recently delineated disorder, characterized by craniofacial, skeletal, visceral, and ocular malformations; and progressive cutaneous, skeletal, vascular, and visceral fragility-related manifestations. Spinal lesions, though one of the most serious complications, have not been investigated systematically. In this study, we report detailed and comprehensive information about spinal lesions of 12 patients with a mean age at the first visit of 13.4 years. Eight patients (66.7%) had scoliosis with a Cobb angle ≥10°, including one with severe scoliosis with a Cobb angle ≥45°. Five patients (41.7%) had kyphosis at the thoracolumbar junction with a kyphotic angle ≥20°. Three patients (25%) developed severe thoracolumbar kyphosis with a kyphotic angle ≥50° accompanied by thoracic lordosis with a wedge-like vertebral deformity and anterior vertebral osteophyte at the thoracolumbar junction, and two of them underwent surgical correction: complicated by fistula formation in one and performed safely and effectively through two-staged operation in the other. Six patients (50.0%) had cervical kyphosis, all of whom except one had kyphosis ≥20° at the thoracolumbar level. Two patients (16.7%) had atlantoaxial subluxation, and 10 patients (83.3%) had cervical vertebral malformations. Patients with mcEDS-CHST14 are susceptible to develop scoliosis, thoracolumbar kyphosis, and cervical kyphosis; and are recommended to have regular surveillance including total spine radiology. The present findings also suggest the critical role of dermatan sulfate in the development and maintenance of the spine.


Assuntos
Síndrome de Ehlers-Danlos/enzimologia , Medula Espinal/patologia , Sulfotransferases/deficiência , Adolescente , Adulto , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Criança , Pré-Escolar , Síndrome de Ehlers-Danlos/diagnóstico por imagem , Feminino , Humanos , Masculino , Medula Espinal/diagnóstico por imagem , Medula Espinal/cirurgia , Sulfotransferases/metabolismo , Tomografia Computadorizada por Raios X , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-29615973

RESUMO

Bone modeling is a biological process of bone formation that adapts bone size and shape to mechanical loads, especially during childhood and adolescence. Bone modeling in cortical bone can be easily detected using sequential radiographic images, while its assessment in trabecular bone is challenging. Here, we performed histomorphometric analysis in 21 bone specimens from biopsies collected during hip arthroplasty, and we proposed the criteria for histologically identifying an active modeling-based bone formation, which we call a "forming minimodeling structure" (FMiS). Evidence of FMiSs was found in 9 of 20 specimens (45%). In histomorphometric analysis, bone volume was significant higher in specimens displaying FMiSs compared with the specimens without these structures (BV/TV, 31.7 ± 10.2 vs. 23.1 ± 3.9%; p < 0.05). Osteoid parameters were raised in FMiS-containing bone specimens (OV/BV, 2.1 ± 1.6 vs. 0.6 ± 0.3%; p < 0.001, OS/BS, 23.6 ± 15.5 vs. 7.6 ± 4.2%; p < 0.001, and O.Th, 7.4 µm ± 2.0 vs. 5.2 ± 1.0; p < 0.05). Our results showed that the modeling-based bone formation on trabecular bone surfaces occurs even during adulthood. As FMiSs can represent histological evidence of modeling-based bone formation, understanding of this physiology in relation to bone homeostasis is crucial.

13.
Biol Pharm Bull ; 40(11): 1934-1940, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29093341

RESUMO

Long-term treatment with antiepileptic drugs (AEDs) is accompanied by reduced bone mass that is associated with an increased risk of bone fractures. Although phenytoin has been reported to adversely influence bone metabolism, little is known pertaining to more recent AEDs. The aim of this study was to evaluate the effects of gabapentin or levetiracetam on bone strength, bone mass, and bone turnover in rats. Male Sprague-Dawley rats were orally administered phenytoin (20 mg/kg), gabapentin (30 or 150 mg/kg), or levetiracetam (50 or 200 mg/kg) daily for 12 weeks. Bone histomorphometric analysis of the tibia was performed and femoral bone strength was evaluated using a three-point bending method. Bone mineral density (BMD) of the femur and tibia was measured using quantitative computed tomography. Administration of phenytoin significantly decreased bone strength and BMD, which was associated with enhanced bone resorption. In contrast, treatment with gabapentin (150 mg/kg) significantly decreased bone volume and increased trabecular separation, as shown by bone histomorphometric analysis. Moreover, the bone formation parameters, osteoid volume and mineralizing surface, decreased after gabapentin treatment, whereas the bone resorption parameters, osteoclast surface and number, increased. Levetiracetam treatment did not affect bone strength, bone mass, and bone turnover. Our data suggested that gabapentin induced the rarefaction of cancellous bone, which was associated with decreased bone formation and enhanced bone resorption, and may affect bone strength and BMD after chronic exposure. To prevent the risk of bone fractures, patients prescribed a long-term administration of gabapentin should be regularly monitored for changes in bone mass.


Assuntos
Anticonvulsivantes/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Reabsorção Óssea/induzido quimicamente , Osso Esponjoso/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Administração Oral , Aminas/efeitos adversos , Animais , Reabsorção Óssea/diagnóstico por imagem , Osso Esponjoso/fisiologia , Ácidos Cicloexanocarboxílicos/efeitos adversos , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Fraturas Ósseas/induzido quimicamente , Fraturas Ósseas/prevenção & controle , Gabapentina , Humanos , Levetiracetam , Masculino , Osteoclastos/efeitos dos fármacos , Fenitoína/efeitos adversos , Piracetam/efeitos adversos , Piracetam/análogos & derivados , Ratos , Ratos Sprague-Dawley , Tíbia/diagnóstico por imagem , Tíbia/fisiologia , Tomografia Computadorizada por Raios X , Ácido gama-Aminobutírico/efeitos adversos
14.
J Pharmacol Sci ; 135(1): 22-28, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28928054

RESUMO

Thiazolidinediones (TZDs) are synthetic peroxisome proliferator-activated receptor gamma (PPARγ) agonists used as therapy for type 2 diabetes. However, clinical studies reported that the therapeutic modulation of PPARγ activity using TZDs may induce negative effects on bone metabolism. This study aimed to evaluate the effect of the TZD pioglitazone on bone metabolism in rats. Male Wistar rats were treated orally with pioglitazone 5 or 20 mg/kg daily for 24 weeks. Bone strength was evaluated using a 3-point bending method, and bone histomorphometry was analyzed. Bone mineral density (BMD) was measured using quantitative computed tomography, and serum biochemical markers were examined. Pioglitazone caused a decrease in cortical and trabecular BMD of whole femur. A reduction in bone strength properties of the femoral mid-diaphysis was observed in the 20 mg/kg pioglitazone treated group. Bone histomorphometric analysis revealed that osteoblast surface and mineralizing surface were decreased, whereas osteoclast surface and number were increased after treatment with 20 mg/kg pioglitazone. Altogether, this study demonstrated that pioglitazone may repress bone formation and facilitate bone resorption. The resulting imbalance of bone metabolism leads to a reduction in BMD with a subsequent increase in bone fragility.


Assuntos
Osso e Ossos/metabolismo , Hipoglicemiantes/efeitos adversos , Tiazolidinedionas/efeitos adversos , Animais , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/induzido quimicamente , Osso e Ossos/patologia , Depressão Química , Relação Dose-Resposta a Droga , Fêmur/metabolismo , Fêmur/patologia , Hipoglicemiantes/administração & dosagem , Masculino , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteogênese/efeitos dos fármacos , PPAR gama/agonistas , Pioglitazona , Ratos Wistar , Tiazolidinedionas/administração & dosagem
15.
PM R ; 8(1): 19-27; quiz 27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25933721

RESUMO

OBJECTIVE: To provide reference values of muscle function (MF) and mobility performance (MP) and to clarify the effects of MF on MP. DESIGN: A normative cross-sectional study. SETTING: An urban area of Niigata, Japan. PARTICIPANTS: A total of 401 individuals (210 men and 191 women) with a mean age of 41.8 years (range, 7-79 years) who lived in the community and did not have impairments in activities of daily living. METHODS: Grip strength, isometric knee extension torque (IKET), and maximum ground reaction force (Fmax) and maximum power (Pmax) during a vertical jump were used as measurements of MF. The chair-rise test (CRT) and the timed "Up and Go" test (TUG) were used to assess MP. MAIN OUTCOME MEASUREMENTS: Mean values of GS, IKET, CRT, TUG, Fmax, and Pmax were calculated according to age and gender. A stepwise multiple regression analysis was used to identify MF factors with an effect on CRT and TUG in participants ≥20 years of age. RESULTS: Our results showed that all MF parameters were decreased in individuals ≥20 years of age compared to those <20 years old. Moreover, all of the MP parameters increasingly deteriorated with increasing age. CRT and TUG were affected by Pmax and IKET in men and by IKET in women according to logistic regression analysis. CONCLUSION: The study findings suggest that muscle power affects MP more than the muscle strength in persons aged ≥20 years.


Assuntos
Atividades Cotidianas , Exercício Físico/fisiologia , Contração Isométrica/fisiologia , Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Torque , Adulto Jovem
16.
Clin Calcium ; 25(4): 531-44, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-25814014

RESUMO

Various care gaps are noted in and between acute and rehabilitation hospitals, and after discharge from hospitals in Japan. In the most of acute care hospitals physicians take care of elderly fractured patients only by a request of orthopaedic team. This made a mean time until surgery was 4.5 days (2011). A critical pathway in treating hip fracture has certainly shortened days in the acute hospitals, care gaps may exist between hospitals. Although osteoporosis medication has started on discharge, it may be discontinued at home, in health or social care facilities under the care of primary care physicians. Even though it was estimated approximately 160,000 hip fractures per year in Japan, management of patients' address is not well established after discharge. In order to include the UK experience in Japan, two proposals were made for hospitals in treating hip fracture as follows. 1. Clinical auditing may be added to improve quality of care. An audit protocol is to be developed multidisciplinarily by orthopaedic surgeons and geriatricians, with interprofessional collaboration. 2. A fracture liaison service is to be established to make interprofessional care-mix possible, such as an increase of adherence of osteoporosis drugs and prevention of falls after discharge. A fracture liaison coordinator is to be assigned to the service in making a team approach possible to a patient and his/her family.


Assuntos
Órgãos dos Sistemas de Saúde , Fraturas do Quadril/terapia , Osteoporose/tratamento farmacológico , Guias de Prática Clínica como Assunto , Ensaios Clínicos como Assunto , Humanos , Japão , Reino Unido
18.
J Bone Miner Res ; 28(2): 395-403, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22991163

RESUMO

Many postmenopausal women have osteopenia, a condition characterized by loss of bone mineral density (BMD) that is not as severe as in osteoporosis. The objective of this study was to estimate the cost-effectiveness of alendronate to prevent fractures in osteopenic postmenopausal women without a history of fracture in Japan. An individual simulation model was developed to predict lifetime costs and quality-adjusted life years (QALYs) of 5 years of preventive alendronate therapy versus no preventive therapy. The risk of hip and vertebral fracture associated with age and BMD was derived from epidemiologic studies in Japan. We ran the model with different combinations of age (65, 70, and 75 years), BMD (70%, 75%, and 80% of young adult mean [YAM]), and additional clinical risk factors. For 70-year-old women with a BMD of 70% of the YAM having one of the following risk factors: a family history of hip fracture, high alcohol intake, or current smoking, the incremental cost-effectiveness ratio (ICER) of alendronate was $92,937, $126,251, and $129,067 per QALY, respectively. These results were sensitive to age, BMD, and number of clinical risk factors. Probabilistic sensitivity analysis for the base case showed that in the presence of one, two, and three risk factors, alendronate was cost-effective in 0.2% to 2.6%, 13.1% to 56.1%, and 99.1% of the simulations, respectively, if society is willing to pay $50,000 per QALY. Additional analysis indicated that alendronate can be a good value in osteopenic women if the 10-year probability for a osteoporotic hip or vertebral fracture is more than 26.2%. Our results indicate that whether to treat osteopenia with alendronate should be determined on the basis of age, BMD, and number of clinical risk factors in terms of cost-effectiveness.


Assuntos
Alendronato/economia , Alendronato/uso terapêutico , Doenças Ósseas Metabólicas/tratamento farmacológico , Doenças Ósseas Metabólicas/economia , Pós-Menopausa , Adulto , Idoso , Idoso de 80 Anos ou mais , Alendronato/farmacologia , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/fisiopatologia , Análise Custo-Benefício , Feminino , Fraturas do Quadril/tratamento farmacológico , Fraturas do Quadril/economia , Humanos , Japão , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/economia , Osteoporose Pós-Menopausa/fisiopatologia , Pós-Menopausa/efeitos dos fármacos , Fatores de Risco , Adulto Jovem
19.
Clin Calcium ; 21(4): 520-7, 2011 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-21447918

RESUMO

In tissue level turnover of bone cells, bone remodeling shows a sequential events of activation, resorption, reversal and formation. This may be observed as secondary osteons in the cortical bone and trabecular packets in the cancellous bone. Microcracks are repaired by targeted remodeling, and calcium is released by non-targeted remodeling. In macromodeling, a macroscopic size of a bone increases with growth, without changing its basic figure. In micromodelimg, a shift of trabecula, a minishift, is biomechnically controlled. New lamellar bone is added parallel to compressive and tensile force, and bone resorption occurs at the opposite surface of formation. In minimodeling new lamellar bone is formed with a sequence of activation, then directly formation, without scalloping at the cement line between newly formed bone and its basic bone.


Assuntos
Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/patologia , Remodelação Óssea/fisiologia , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Animais , Osso e Ossos/citologia , Humanos , Osteócitos/patologia , Osteócitos/fisiologia , Osteogênese
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