RESUMEN
Postmenopausal osteoporosis (PMOP) therapies are frequently evaluated by bone mineral density (BMD) gains against patients receiving placebo (calcium and vitamin D supplementation, a mild bone turnover-suppressing intervention), which is not equivalent to either healthy or treatment-naive PMOP. The aim of the present observational study was to assess the effects of TPTD treatment in PMOP (20 µg, once daily) at 6 (TPTD 6m; n = 28, age 65 ± 7.3 years), and 24 (TPTD 24m; n = 32, age 67.4 ± 6.15 years) months on bone quality indices at actively forming trabecular surfaces (with fluorescent double labels). Data from the TPTD-treated PMOP patients were compared with those in healthy adult premenopausal women (HC; n = 62, age 40.5 ± 10.6 years), and PMOP receiving placebo (PMOP-PLC; n = 94, age 70.6 ± 4.5 years). Iliac crest biopsies were analyzed by Raman microspectroscopy at three distinct tissue ages: mid-distance between the second label and the bone surface, mid-distance between the two labels, and 1 µm behind the first label. Mineral to matrix ratio (MM), mineral maturity/crystallinity (MMC), tissue water (TW), glycosaminoglycan (GAGs), and pyridinoline (Pyd) content were determined. Outcomes were compared by ANCOVA with subject age and tissue age as covariates, and health status as a fixed factor, followed by Sidak's post-hoc testing (significance assigned to p < 0.05). Both TPTD groups increased MM compared to PMOP-PLC. While TPTD 6m had values similar to HC, TPTD 24m had higher values compared to either HC or TPTD 6m. Both TPTD groups had lower MMC values compared to PMOP-PLC and similar to HC. TPTD 6m patients had higher TW content compared to HC, while TPTD 24m had values similar to HC and lower than either PMOP-PLC or TPTD 6m. Both TPTD groups had lower GAG content compared to HC group, while TPTD 6m had higher values compared to PMOP-PLC. Finally, TPTD 6m patients had higher Pyd content compared to HC and lower compared to PMOP-PLC, while TPTD 24m had lower values compared to PMOP-PLC and TPTD 6m, and similar to HC group. The results of the present study indicate that effects of TPTD on forming trabecular bone quality indices depend on treatment duration. At the recommended length of 24 m, TPTD restores bone mineral and organic matrix quality indices (MMC, TW, Pyd content) to premenopausal healthy (HC) levels.
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Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Adulto , Anciano , Densidad Ósea , Conservadores de la Densidad Ósea/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Humanos , Ilion/patología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/patología , Teriparatido/farmacología , Teriparatido/uso terapéuticoRESUMEN
AIM: To investigate the prognostic significance of bone marrow (BM) 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) uptake in relation to posterior iliac crest BM biopsy (BMB) results in diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: Pretreatment integrated positron-emission tomography(PET)/computed tomography (CT) images of 512 DLBCL patients who underwent BMB and received rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy were analysed retrospectively. BM uptake was assessed visually and by maximum standard uptake value (SUVmax). Associations with lymphoma-specific survival (LSS) were assessed using Kaplan-Meier and Cox regression analyses. RESULTS: FDG(+) BM was observed in 64 cases (41 focal, 12 heterogeneous, 11 diffuse). This finding distinguished iliac crest involvement (positive in 59 and negative in 453) with 89.6% accuracy (459/512) and 93.6% specificity (424/453). In BMB(+) patients, BM-to-liver SUVmax ratio >1.8 concurred perfectly with FDG(+) BM. During 52 months of follow-up, there were 156 lymphoma-related deaths. In the entire population, multivariate analysis revealed high International Prognostic Index (IPI; p<0.001), old age (p=0.003), bulky disease (p=0.011), BMB(+) (p=0.028), and FDG(+) BM (p=0.019) as independent predictors of worse LSS. In the BMB(+) subgroup, high National Comprehensive Cancer Network-revised IPI (NCCN-IPI; p=0.029) and FDG(+) BM (p=0.008) were significant independent predictors. Among BMB(+) patients with low to low-intermediate NCCN-IPI, FDG(+) BM was associated with significantly worse 2-year LSS (33.3% versus 100%; p=0.017). The same was true among those with high-intermediate NCCN-IPI (34.7% versus 76.9%.; p=0.026). CONCLUSION: Increased BM FDG in DLBCL is a predictor of worse LSS independent of BMB results and other prognostic variables including IPI/NCCN-IPI.
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Médula Ósea/patología , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biopsia , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Femenino , Fluorodesoxiglucosa F18 , Humanos , Ilion/patología , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Prednisona/uso terapéutico , Pronóstico , Radiofármacos , Estudios Retrospectivos , Rituximab/uso terapéutico , Tasa de Supervivencia , Vincristina/uso terapéuticoRESUMEN
BACKGROUND: Whilst hypocalcemic complications from vitamin D deficiency are considered rare in high-income countries, they are highly prevalent among Black, Asian and Minority Ethnic (BAME) group with darker skin. To date, the extent of osteomalacia in such infants and their family members is unknown. Our aim was to investigate clinical, cardiac and bone histomorphometric characteristics, bone matrix mineralization in affected infants and to test family members for biochemical evidence of osteomalacia. CASE PRESENTATION: Three infants of BAME origin (aged 5-6 months) presented acutely in early-spring with cardiac arrest, respiratory arrest following seizure or severe respiratory distress, with profound hypocalcemia (serum calcium 1.22-1.96 mmol/L). All infants had dark skin and vitamin D supplementation had not been addressed during child surveillance visits. All three had severely dilated left ventricles (z-scores + 4.6 to + 6.5) with reduced ejection fraction (25-30%; normal 55-70), fractional shortening (7 to 15%; normal 29-40) and global hypokinesia, confirming hypocalcemic dilated cardiomyopathy. They all had low serum levels of 25 hydroxyvitamin D (25OHD < 15 nmol/L), and elevated parathyroid hormone (PTH; 219-482 ng/L) and alkaline phosphatase (ALP; 802-1123 IU/L), with undiagnosed rickets on radiographs. One infant died from cardiac arrest. At post-mortem examination, his growth plate showed a widened, irregular zone of hypertrophic chondrocytes. Histomorphometry and backscattered electron microscopy of a trans-iliac bone biopsy sample revealed increased osteoid thickness (+ 262% of normal) and osteoid volume/bone volume (+ 1573%), and extremely low bone mineralization density. Five of the nine tested family members had vitamin D deficiency (25OHD < 30 nmol/L), three had insufficiency (< 50 nmol/L) and 6/9 members had elevated PTH and ALP levels. CONCLUSIONS: The severe, hidden, cardiac and bone pathology described here exposes a failure of public health prevention programs, as complications from vitamin D deficiency are entirely preventable by routine supplementation. The family investigations demonstrate widespread deficiency and undiagnosed osteomalacia in ethnic risk groups and call for protective legislation.
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Cardiomiopatía Dilatada/etiología , Paro Cardíaco/etiología , Hipocalcemia/complicaciones , Grupos Minoritarios , Osteomalacia/etiología , Insuficiencia Respiratoria/etiología , Raquitismo/complicaciones , Densidad Ósea , Inglaterra , Femenino , Placa de Crecimiento/patología , Humanos , Hipocalcemia/etnología , Hipocalcemia/patología , Ilion/patología , Lactante , Masculino , Raquitismo/etnología , Raquitismo/patologíaRESUMEN
UNLABELLED: We demonstrate histological evidence for hyperparathyroidism in patients with gastrectomy. This is, at least in part, explained by impaired calcium absorption, resulting in mineralization defects and secondary hyperparathyroidism. Additionally, we demonstrate improved bone mineralization in patients with gastrectomy after gluconate therapy and showed the effectiveness of calcium gluconate over carbonate to balance impaired calcium hemostasis in mice. INTRODUCTION: Gastrectomy and hypochlorhydria due to long-term proton pump inhibitor therapy are associated with increased fracture risk because of intestinal calcium malabsorption. Hence, our objectives were to histologically investigate bone metabolism in patients with gastrectomy and to analyze the impact of calcium gluconate supplementation on skeletal integrity in the setting of impaired gastric acidification. METHODS: Undecalcified bone biopsies of 26 gastrectomized individuals were histologically analyzed. In the clinical setting, we retrospectively identified 5 gastrectomized patients with sufficient vitamin D level, who were additionally supplemented with calcium gluconate and had a real bone mineral density (aBMD) follow-up assessments. A mouse model of achlorhydria (ATP4b-/-) was used to compare the effect of calcium gluconate and calcium carbonate supplementation on bone metabolism. RESULTS: Biopsies from gastrectomized individuals showed significantly increased osteoid, osteoclast, and osteoblast indices and fibroosteoclasia (p < 0.05) as well as impaired calcium distribution in mineralized bone matrix compared to healthy controls. Five gastrectomized patients with sufficient vitamin D level demonstrated a significant increase in aBMD after a treatment with calcium gluconate alone for at least 6 months (p < 0.05). Calcium gluconate was superior to calcium carbonate in maintaining calcium metabolism in a mouse model of achlorhydria. CONCLUSION: Gastrectomy is associated with severe osteomalacia, marrow fibrosis, and impaired calcium distribution within the mineralized matrix. We show that calcium gluconate supplementation can increase bone mineral density in gastrectomized individuals and performs superior to calcium carbonate in restoring calcium/skeletal homoeostasis in a mouse model of achlorhydria.
Asunto(s)
Gluconato de Calcio/uso terapéutico , Gastrectomía/efectos adversos , Hiperparatiroidismo Secundario/tratamiento farmacológico , Osteoporosis/tratamiento farmacológico , Aclorhidria/tratamiento farmacológico , Anciano , Animales , Biopsia , Densidad Ósea/efectos de los fármacos , Calcio/metabolismo , Gluconato de Calcio/farmacología , Carbamatos/uso terapéutico , Suplementos Dietéticos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos/métodos , Femenino , Homeostasis/efectos de los fármacos , Humanos , Hiperparatiroidismo Secundario/etiología , Hiperparatiroidismo Secundario/metabolismo , Ilion/patología , Masculino , Ratones Noqueados , Persona de Mediana Edad , Osteoblastos/patología , Osteoclastos/patología , Osteoporosis/etiología , Osteoporosis/patología , Osteoporosis/fisiopatología , Estudios RetrospectivosRESUMEN
PURPOSE: The design of an implant plays a fundamental role in the osseointegration process, particularly in low-density bone. It has been postulated that design features that maximize the surface area available for contact may improve mechanical anchorage and primary stability in cancellous bone. Two different implant profiles were compared to evaluate the influence of thread pitch on the osseointegration process in bone of low density and limited height. MATERIALS AND METHODS: "Narrow-pitch" implants (NP) with a 0.5-mm pitch and "wide-pitch" implants (WP) with a 1.7-mm pitch were tested for osseointegration after 0 days and 4 and 8 weeks in a sheep iliac crest model. The two different implants were analyzed with biologic and biomechanical tests. RESULTS: The present findings showed that initial mechanical anchorage and subsequent early endosseous integration in low-density bone could be improved by a reduction of thread pitch. The greater surface area gained by decreasing thread pitch increased bone-implant contact and primary stability from the time of implant placement. This better performance of the NP profile could be appreciated even at an early healing time when the subsequent biologic integration was enhanced not only in terms of a higher quantity of newly deposited bone but also more regular and mature geometric distribution of bone tissue at the interface. CONCLUSION: These results confirmed that, when primary stability is a concern, as in cancellous bone, increasing the implant surface area by using implants with smaller pitch might be beneficial.
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Implantes Dentales , Diseño de Prótesis Dental , Oseointegración/fisiología , Grabado Ácido Dental/métodos , Óxido de Aluminio/química , Animales , Fenómenos Biomecánicos , Densidad Ósea/fisiología , Matriz Ósea/patología , Grabado Dental/métodos , Implantación Dental Endoósea/métodos , Materiales Dentales/química , Retención de Prótesis Dentales , Ilion/patología , Ilion/cirugía , Microscopía Electrónica de Rastreo , Osteogénesis/fisiología , Osteotomía/métodos , Ovinos , Propiedades de Superficie , Factores de Tiempo , Titanio/química , TorqueRESUMEN
Hypoparathyroidism (hypoPT) is characterized by a state of low bone turnover and high bone mineral density (BMD) despite conventional treatment with calcium supplements and active vitamin D analogues. To assess effects of PTH substitution therapy on 3-dimensional bone structure, we randomized 62 patients with hypoPT into 24 weeks of treatment with either PTH(1-84) 100 µg/day subcutaneously or similar placebo as an add-on therapy. Micro-computed tomography was performed on 44 iliac crest bone biopsies (23 on PTH treatment) obtained after 24 weeks of treatment. Compared with placebo, PTH caused a 27% lower trabecular thickness (p < 0.01) and 4% lower trabecular bone tissue density (p < 0.01), whereas connectivity density was 34% higher (p < 0.05). Trabecular tunneling was evident in 11 (48%) of the biopsies from the PTH group. Patients with tunneling had significantly higher levels of biochemical markers of bone resorption and formation. At cortical bone, number of Haversian canals per area was 139% higher (p = 0.01) in the PTH group, causing a tendency toward an increased cortical porosity (p = 0.09). At different subregions of the hip, areal BMD (aBMD) and volumetric BMD (vBMD), as assessed by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT), decreased significantly by 1% to 4% in the PTH group. However, at the lumbar spine, aBMD decreased by 1.8% (p < 0.05), whereas vBMD increased by 12.8% (p = 0.02) in the PTH compared with the placebo group.
Asunto(s)
Hipoparatiroidismo/tratamiento farmacológico , Ilion/patología , Hormona Paratiroidea/farmacología , Hormona Paratiroidea/uso terapéutico , Adulto , Anciano , Densidad Ósea/efectos de los fármacos , Femenino , Humanos , Hipoparatiroidismo/diagnóstico por imagen , Ilion/efectos de los fármacos , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/administración & dosificación , Microtomografía por Rayos XRESUMEN
Osteomalacia can be a late but unrecognized complication following jejunoileal bypass. We describe a 53-year-old man who underwent jejunoileal bypass for morbid obesity twenty years earlier who suffered from progressive diffuse bony pain refractory to nonsteroidal anti-inflammatory drugs. He was initially diagnosed with a malignancy with bone metastasis. However, pertinent laboratory data were notable for hypocalcemia (7.5 mg/dL, albumin 4.1 mg/dL) with low urinary calcium excretion (14 mg/day), hypophosphatemia (2.0 mg/dL) with low urinary phosphate excretion (53 mg/day), hypomagnesemia (1.5 mg/dL) with low urine magnesium excretion (23 mg/day), low 1, 25 (OH)2 vitamin D3, and elevated serum alkaline phosphatase and intact parathyroid hormone (iPTH). These laboratory findings pointed to a defect in calcium, phosphate, and magnesium handling in the gastrointestinal tract. Bone biopsy of the iliac crest clearly demonstrated typical changes of osteomalacia with excessive osteoid accumulation and reduced mineralization. His clinical symptoms were refractory to oral 1, 25 (OH)2 vitamin D3 and calcium supplementation but significantly improved with the addition of intermittent intravenous active 1, 25 (OH)2 vitamin D3, calcium, phosphate, and magnesium supplementation. Osteomalacia is an easily misdiagnosed late complication of jejunoileal bypass. Early recognition can avoid circuitous diagnosis and inappropriate management.
Asunto(s)
Dolor en el Pecho/etiología , Cadera , Derivación Yeyunoileal/efectos adversos , Osteomalacia/diagnóstico , Osteomalacia/etiología , Dolor Postoperatorio/etiología , Dolor de Hombro/etiología , Biopsia , Dolor en el Pecho/patología , Diagnóstico Diferencial , Cadera/patología , Humanos , Ilion/patología , Masculino , Persona de Mediana Edad , Osteomalacia/patología , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/patología , Dolor Postoperatorio/terapia , Cuidados Posoperatorios , Cintigrafía , Dolor de Hombro/patología , Medronato de Tecnecio Tc 99mRESUMEN
Parathyroid hormone (PTH) is only one measurable index of skeletal health, and we reasoned that a histomorphometric analysis of iliac crest biopsies would be another and even more direct approach to assess bone health and address the required minimum 25-Hydroxyvitamin D [25(OH)D] level. A cohort from the northern European population with its known high prevalence of vitamin D deficiency therefore would be ideal to answer the latter question. We examined 675 iliac crest biopsies from male and female individuals, excluding all patients who showed any signs of secondary bone diseases at autopsy. Structural histomorphometric parameters, including osteoid indices, were quantified using the Osteomeasure System according to ASBMR standards, and serum 25(OH)D levels were measured for all patients. Statistical analysis was performed by Student's t test. The histologic results demonstrate an unexpected high prevalence of mineralization defects, that is, a pathologic increase in osteoid. Indeed, 36.15% of the analyzed patients presented with an osteoid surface per bone surface (OS/BS) of more than 20%. Based on the most conservative threshold that defines osteomalacia at the histomorphometric level with a pathologic increase in osteoid volume per bone volume (OV/BV) greater than 2% manifest mineralization defects were present in 25.63% of the patients. The latter were found independent of bone volume per trabecular volume (BV/TV) throughout all ages and affected both sexes equally. While we could not establish a minimum 25(OH)D level that was inevitably associated with mineralization defects, we did not find pathologic accumulation of osteoid in any patient with circulating 25(OH)D above 75 nmol/L. Our data demonstrate that pathologic mineralization defects of bone occur in patients with a serum 25(OH)D below 75 nmol/L and strongly argue that in conjunction with a sufficient calcium intake, the dose of vitamin D supplementation should ensure that circulating levels of 25(OH)D reach this minimum threshold (75 nmol/L or 30 ng/mL) to maintain skeletal health.
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Desmineralización Ósea Patológica/complicaciones , Calcificación Fisiológica , Ilion/patología , Deficiencia de Vitamina D/complicaciones , Vitamina D/análogos & derivados , Anciano , Desmineralización Ósea Patológica/patología , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Vitamina D/sangre , Deficiencia de Vitamina D/patologíaRESUMEN
UNLABELLED: Although it is known that neurofibromatosis 1 (NF1) patients suffer from vitamin D deficiency and display decreased bone mineral density (BMD), a systematic clinical and histomorphometrical analysis is absent. Our data demonstrate that NF1 patients display high bone turnover and accumulation of osteoid and that supplementation of vitamin D has a beneficial effect on their BMD. INTRODUCTION: Neurofibromatosis 1 results in a wide range of clinical manifestations, including decreased BMD. Although it has been reported that NF1 patients have decreased vitamin D serum levels, the manifestation of the disease at the bone tissue level has rarely been analyzed. METHODS: Thus, we performed a clinical evaluation of 14 NF1 patients in comparison to age- and sex-matched control individuals. The analysis included dual X-ray absorptiometry osteodensitometry, laboratory parameters, histomorphometric and quantitative backscattered electron imaging (qBEI) analyses of undecalcified bone biopsies. RESULTS: NF1 patients display significantly lower 25-(OH)-cholecalciferol serum levels and decreased BMD compared to control individuals. Histomorphometric analysis did not only reveal a reduced trabecular bone volume in biopsies from NF1 patients, but also a significantly increased osteoid volume and increased numbers of osteoblasts and osteoclasts. Moreover, qBEI analysis revealed a significant decrease of the calcium content in biopsies from NF1 patients. To address the question whether a normalization of calcium homeostasis improves BMD in NF1 patients, we treated four patients with cholecalciferol for 1 year, which resulted in a significant increase of BMD. CONCLUSION: Taken together, our data provide the first complete histomorphometric analysis from NF1 patients. Moreover, they suggest that low vitamin D levels significantly contribute to the skeletal defects associated with the disease.
Asunto(s)
Remodelación Ósea/fisiología , Neurofibromatosis 1/complicaciones , Osteoporosis/etiología , Absorciometría de Fotón/métodos , Adulto , Anciano , Biopsia , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Conservadores de la Densidad Ósea/uso terapéutico , Calcifediol/sangre , Calcio/sangre , Colecalciferol/uso terapéutico , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Ilion/patología , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Neurofibromatosis 1/sangre , Neurofibromatosis 1/patología , Neurofibromatosis 1/fisiopatología , Osteoporosis/tratamiento farmacológico , Osteoporosis/patología , Osteoporosis/fisiopatología , Hormona Paratiroidea/sangre , Fosfatos/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/etiología , Adulto JovenRESUMEN
The aim of the study was the histomorphometric comparison of the osteogenic potential of beta-tricalcium phosphate (beta-TCP) alone or in a calcium sulfate matrix. Three round defects, 10 mm (diameter) x 5 mm (depth), were created on each iliac crest of 4 dogs. The defects were divided into 3 groups. Ten defects were filled with beta-TCP in a calcium sulfate (CS) matrix (Fortoss Vital; group A), 10 defects were filled with beta-TCP alone (Fortoss Resorb; group B), and 4 defects were left ungrafted to heal spontaneously (group C). All defects were left to heal for 4 months without the use of a barrier membrane. Histologic evaluation and morphometric analysis of undecalcified slides was performed using the areas of regenerated bone and graft remnants. All sites exhibited uneventful healing. In group A sites (beta-TCP/CS), complete bone formation was observed in all specimens, graft granules dominated the area, and a thin bridge of cortical bone was covering the defect. Group B (beta-TCP) defects were partially filled with new bone, the graft particles still dominated the area, while the outer cortex was not restored. In the ungrafted sites (group C), incomplete new bone formation was observed. The outer dense cortical layer was restored in a lower level, near the base of the defect. The statistical analysis revealed that the mean percentage of new bone regeneration in group A was higher than in group B (49.38% and 40.31%, respectively). A statistically significant difference existed between the 2 groups. The beta-TCP/CS group exhibited significantly higher new bone regeneration according to a marginal probability value (P = .004 < .05). The use of beta-TCP in a CS matrix produced significantly more vital new bone fill and preserved bone dimensions compared with the use of beta-TCP alone.
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Materiales Biocompatibles/uso terapéutico , Regeneración Ósea/fisiología , Sustitutos de Huesos/uso terapéutico , Fosfatos de Calcio/uso terapéutico , Sulfato de Calcio/química , Animales , Tejido Conectivo/patología , Perros , Portadores de Fármacos , Epitelio/patología , Osteón/patología , Ilion/patología , Ilion/cirugía , Procesamiento de Imagen Asistido por Computador , Modelos Animales , Osteogénesis/fisiología , Grabación en Video , Cicatrización de Heridas/fisiologíaRESUMEN
The objective of this study was to compare the osteogenic potential of human embryonic stem cells (hESCs) within two- and three-dimensional (2D and 3D) culture systems. hESCs of the H1 line (Wicell Inc., Madison, Wisc., USA) were induced to form embryoid bodies (EBs) through 5 days of suspension culture within non-adherent culture dishes. Following enzymatic dissociation, the EB-derived single cells were seeded on either novel 3D porous PLGA scaffolds or 2D culture dishes with the same total cell number. Osteogenic differentiation was induced through culture media supplemented with dexamethasone, L-ascorbic acid and beta-glycerophosphate. After 3 weeks of in vitro culture, quantitative and qualitative assays of osteogenic differentiation were conducted. Osteocalcin secretion and alkaline phosphatase (AP) activities were detected at significantly higher levels within 3D culture compared with the 2D system. Subsequently, the cell-scaffold constructs were implanted in iliac crest defects of immunosuppressed rabbits. After 4 weeks, the constructs were subsequently explanted and characterized by histology and X-ray analysis. Formation of new bone was detected within and around the implanted scaffolds. The results demonstrate that the osteogenic differentiation of human embryonic stem cells is enhanced in a 3D culture system compared to a 2D culture environment. Upon implantation in situ, the differentiating human embryonic stem cells can contribute positively to the repair and regeneration of bone defects.
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Células Madre Embrionarias/citología , Osteogénesis/fisiología , Ingeniería de Tejidos/métodos , Fosfatasa Alcalina/metabolismo , Animales , Antígenos de Superficie/metabolismo , Ácido Ascórbico/farmacología , Regeneración Ósea , Calcificación Fisiológica/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Dexametasona/farmacología , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/metabolismo , Glicerofosfatos/farmacología , Humanos , Ilion/patología , Ilion/cirugía , Implantes Experimentales , Ácido Láctico/química , Masculino , Microscopía Confocal , Factor 1 de Transcripción de Unión a Octámeros/metabolismo , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Conejos , Técnicas de Cultivo de Tejidos/métodos , Andamios del Tejido/químicaRESUMEN
Disturbances in mineral metabolism play a central role in the development of renal bone disease. In a 54-wk, randomized, open-label study, 119 hemodialysis patients were enrolled to compare the effects of sevelamer hydrochloride and calcium carbonate on bone. Biopsy-proven adynamic bone disease was the most frequent bone abnormality at baseline (59%). Serum phosphorus, calcium, and intact parathyroid hormone were well controlled in both groups, although calcium was consistently lower and intact parathyroid hormone higher among patients who were randomly assigned to sevelamer. Compared with baseline values, there were no changes in mineralization lag time or measures of bone turnover (e.g., activation frequency) after 1 yr in either group. Osteoid thickness significantly increased in both groups, but there was no significant difference between them. Bone formation rate per bone surface, however, significantly increased from baseline only in the sevelamer group (P = 0.019). In addition, of those with abnormal microarchitecture at baseline (i.e., trabecular separation), seven of 10 in the sevelamer group normalized after 1 yr compared with zero of three in the calcium group. In summary, sevelamer resulted in no statistically significant changes in bone turnover or mineralization compared with calcium carbonate, but bone formation increased and trabecular architecture improved with sevelamer. Further studies are required to assess whether these changes affect clinical outcomes, such as rates of fracture.
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Antiácidos/administración & dosificación , Carbonato de Calcio/administración & dosificación , Quelantes/administración & dosificación , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Poliaminas/administración & dosificación , Adulto , Anciano , Biopsia , Calcificación Fisiológica/efectos de los fármacos , Calcio/sangre , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/patología , Femenino , Humanos , Ilion/efectos de los fármacos , Ilion/patología , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Fósforo/sangre , Diálisis Renal , Sevelamer , Resultado del TratamientoRESUMEN
The purpose of this paper is to present the orthopedic-oncologic and functional outcomes of internal partial hemipelvectomy for a secondary giant pelvic chondrosarcoma in a patient with multiple hereditary osteochondromatosis.
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Condrosarcoma/cirugía , Exostosis Múltiple Hereditaria , Hemipelvectomía/métodos , Neoplasias Pélvicas/cirugía , Adulto , Trasplante Óseo , Condrosarcoma/genética , Terapia Combinada , Embolización Terapéutica , Femenino , Rechazo de Injerto , Humanos , Hipertermia Inducida , Ilion/patología , Ilion/cirugía , Neoplasias Pélvicas/genéticaRESUMEN
UNLABELLED: Long-term effects of risedronate on bone mineral maturity/crystallinity and collagen cross-link ratio in triple iliac crest biopsies of osteoporotic women were evaluated. In this double-blinded study, 3- and 5-year treatment with risedronate arrested the tissue aging encountered in untreated osteoporosis and in osteoporosis treated with other antiresorptives. This effect may be contributing to risedronate's antifracture efficacy. INTRODUCTION: Risedronate is widely used in the treatment of osteoporosis. It reduces bone turnover, increases BMD, and decreases fracture risk. To date, there are no data available on the long-term effects of risedronate on bone material properties in humans. MATERIALS AND METHODS: Osteoporotic women enrolled in the VERT-NA trial received either risedronate (5 mg/day, orally) or placebo for up to 5 years. All subjects received calcium. They also received vitamin D supplementation if deficient at baseline. Triple iliac crest biopsies were collected from a subset of these subjects at baseline, 3 years, and 5 years. Mineral maturity/crystallinity and collagen cross-link ratio was measured in these biopsies using Fourier transform infrared imaging. RESULTS: Patients that received placebo exhibited increased mineral maturity/crystallinity and collagen cross-link ratio after 3 and 5 years compared with baseline values. On the contrary, patients that received risedronate retained baseline values in both bone material indices throughout. A more spatially detailed analysis revealed that this was achieved mainly through beneficial effects on active bone-forming areas. Surprisingly, patients that received risedronate achieved premenopausal values at bone-forming areas in both indices after 5 years of treatment. CONCLUSION: Long-term treatment with risedronate affects bone material properties (mineral maturity/crystallinity and collagen cross-link ratio) and arrests the tissue aging apparent in untreated osteoporosis. These changes at the material level of the bone matrix may contribute to risedronate's rapid and sustained antifracture efficacy in osteoporotic patients.
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Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Ácido Etidrónico/análogos & derivados , Ilion/patología , Biopsia , Conservadores de la Densidad Ósea/administración & dosificación , Calcificación Fisiológica/efectos de los fármacos , Calcio/uso terapéutico , Colágeno/efectos de los fármacos , Colágeno/metabolismo , Ácido Etidrónico/administración & dosificación , Ácido Etidrónico/uso terapéutico , Femenino , Humanos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Ácido Risedrónico , Espectroscopía Infrarroja por Transformada de Fourier , Vitamina D/uso terapéuticoRESUMEN
Bisphosphonates have been used successfully in the treatment of malignant hypercalcemia and skeletal metastases. Recently, clodronate has been studied in adjuvant settings in primary breast cancer. However, long-term effect of adjuvant clodronate on bone histology has not been reported, whereas bone mineral density studies have been published. The aim of this study was to examine the effect and safety of long-term clodronate treatment on bone quality as measured by histomorphometric techniques from bone biopsies. A total of 299 patients with early stage breast cancer were randomized to receive adjuvant oral clodronate (1.6 g/day) or to a control group for 3 years. All patients had adjuvant treatment: premenopausal women had six cycles of chemotherapy and postmenopausal women had antiestrogen for 3 years. Trabecular bone quality was examined in transiliac bone biopsy specimens by using histomorphometric techniques in 28 clodronate treated and 35 control patients who were disease-free at 3 years and who allowed the biopsy specimen to be obtained. No statistically significant differences were found in the values of osteoid, mineral apposition rate, or mineralization lag time in bone biopsies between the clodronate and the control groups. Postmenopausal women who received two antiresorptive drugs, antiestrogen and clodronate, developed features of secondary hyperparathyroidism with increased eroded surface and osteoclast number. In premenopausal, women clodronate with adjuvant chemotherapy, which induced early menopause and rapid bone loss in most of the patients, seemed to conduct slight depression in bone formation. Three-year oral clodronate treatment does not impair mineralization of newly formed bone: however, clodronate with different adjuvant breast cancer treatments has a diverse impact on bone histomorphometry depending on the type of therapy.
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Antimetabolitos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Calcificación Fisiológica/efectos de los fármacos , Ácido Clodrónico/uso terapéutico , Ilion , Administración Oral , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Ciclofosfamida/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Ilion/efectos de los fármacos , Ilion/metabolismo , Ilion/patología , Metotrexato/administración & dosificación , Persona de Mediana EdadRESUMEN
BACKGROUND: Although there is good evidence that spinal manipulation is an effective treatment to improve pain and function for patients with low back pain (LBP), there is little evidence to support the mechanism by which manipulation works. OBJECTIVES: To determine if iliac crest (IC) and weight-bearing (WB) symmetry improve after spinal manipulation and to determine if improvements in IC and WB symmetry are associated with improvements in pain and function in patients with low back pain. DESIGN: Single group, within-subjects, repeated measures design. METHOD: Thirty consecutive patients (mean age = 40+/-13) who came to a spine specialty center for treatment of acute or chronic LBP and who would be receiving spinal manipulation participated in the study (14 male patients). Patients completed a series of self-report measures of pain and function and received a standardized physical examination, including the assessment of IC and WB symmetry. Patients received a standardized manipulative intervention, and immediate and 3- to 4-day follow-up examinations were performed by a blinded examiner. Paired t tests were performed to determine within-group changes, and Pearson product moment correlation coefficients were calculated to determine the relationship between improvements in IC and WB symmetry and improvements in pain and function. To control for the potential that an association between changes in IC and/or WB symmetry and changes in pain and function could be confounded by the baseline outcome measure, simultaneous linear regression was performed on any significant correlation. Partial F tests were used to determine if the additional explained variability was significant. RESULTS: Patients with LBP demonstrated significant improvements in IC and WB symmetry after manipulation (P<.001). Improvements in WB symmetry were associated with improvements in the patients' self-reported levels of pain 3 to 4 days after manipulation (r=.5, P=.007). Based on the significant association between improvements in WB symmetry and improvements in pain, the final pain score was regressed on the change in WB symmetry, after controlling for the baseline level of pain. The addition of the change in WB symmetry explained a 10% additional increase in variability in the patient's level of pain at the 3- to 4-day follow-up (P =.01). No relationship was found between improvements in IC and WB symmetry and improvements in function as determined by the Oswestry Disability Questionnaire 3 to 4 days after manipulation. CONCLUSION: IC and WB symmetry improved immediately after spinal manipulation. Improvements in WB symmetry were related to improvements in the patients' self-reported levels of pain, even after controlling for the baseline level of pain. Improvements in IC and WB symmetry were not related to changes in function. The results of this study provide initial data to elucidate how manipulation may work to improve pain and function in patients with LBP.
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Ilion/patología , Dolor de la Región Lumbar/terapia , Manipulación Espinal , Soporte de Peso , Adolescente , Adulto , Anciano , Femenino , Humanos , Dolor de la Región Lumbar/patología , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Examen Físico , Recuperación de la Función , Índice de Severidad de la Enfermedad , Método Simple Ciego , Encuestas y Cuestionarios , Resultado del TratamientoRESUMEN
BACKGROUND: Successful parathyroidectomy for secondary hyperparathyroidism alleviates bone pain and is followed by the development of hypophosphatemia and hypocalcemia, as well as an increase in bone mineral density. An increase in osteoblast surface (Ob.S/BS) is not observed several months after surgery. In this study, we investigated early bone changes at 1 week after parathyroidectomy and the mechanism underlying an increase in bone mineral density. METHODS: Fourteen patients with severe secondary hyperparathyroidism underwent iliac bone biopsy before and 1 week after parathyroidectomy. Changes in histomorphometric parameters, including osteoclast surface (Oc.S/BS), eroded surface (ES/BS), erosion depth (E.De), fibrosis volume (Fb.V/TV), Ob.S/BS, osteoid volume (OV/BV), osteoid surface (OS/BS), and osteoid thickness (O.Th), were investigated. Changes in texture of mineralized bone and osteoid seams were also investigated. RESULTS: Oc.S/BS (P < 0.001), ES/BS (P < 0.01), and E.De (P < 0.001) decreased, but Fb.V/TV did not change at 1 week postoperatively. In particular, osteoclasts disappeared in almost all patients. Ob.S/BS (P < 0.001) increased, and cuboidal osteoblasts were proliferating on the trabecular surface where osteoclasts had existed before parathyroidectomy. As a result, newly developed osteoblasts coexisted with fibrous tissue after surgery. OV/BV (P < 0.005), OS/BS (P < 0.005), and O.Th (P < 0.005) increased, with lamellar osteoid volume showing a particular increase. Bone mineralization continued despite the low postoperative serum parathyroid hormone level. CONCLUSION: A rapid decrease in serum parathyroid hormone level after parathyroidectomy appears to suppress bone resorption, as well as cause a transient marked increase in bone formation and an increase in normal lamellar osteoid seams.
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Remodelación Ósea/fisiología , Hiperparatiroidismo Secundario/cirugía , Osteoblastos/clasificación , Osteoclastos/clasificación , Osteogénesis/fisiología , Paratiroidectomía , Adulto , Biopsia , Densidad Ósea , Resorción Ósea , Calcio/sangre , Femenino , Humanos , Hiperparatiroidismo Secundario/patología , Hiperparatiroidismo Secundario/fisiopatología , Ilion/patología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Fósforo/sangreRESUMEN
BACKGROUND: To date, the reliability studies of iliac crest (IC) level used nominal scales and presented conflicting results. To perform the IC level measurement, we propose the use of a measurement device that is composed of an inclinometer mounted on a crest level tester that measures IC level in degrees. OBJECTIVES: To determine the interrater reliability of measuring iliac crest level in the standing and sitting position using an experimental device and to assess the precision of the measurements taken with the experimental device. METHOD: Forty individuals (mean age 40 +/- 12 years) referred to physical therapy for treatment of low back pain (LBP) participated in the study (16 male participants). Six examiners performed the measurements. Three of the 6 examiners performed the measurements on each individual. Each examiner independently performed the measurement of IC level in standing and in sitting using the measurement device. RESULTS: Intraclass correlation coefficients, [formula (1,1)] for measurement of IC level in standing and sitting, were 0.80 (95% CI = 0.7-0.9) and 0.73 (95% CI = 0.6-0.8), respectively. Standard errors of measurement for IC level in standing and sitting were 0.91 and 0.86 degrees, respectively. CONCLUSION: The use of a measurement device resulted in good reliability of IC level measurement in degrees in standing and moderate reliability of IC level in sitting position. This finding is relevant to plan future studies that will investigate if changes in IC level may be associated with outcomes of pain and function in patients with low back or pelvic dysfunctions.
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Ilion/patología , Dolor de la Región Lumbar , Vértebras Lumbares/patología , Postura , Adulto , Diseño de Equipo , Equipos y Suministros , Estudios de Evaluación como Asunto , Femenino , Humanos , Dolor de la Región Lumbar/fisiopatología , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
We examined paired iliac crest bone biopsy specimens from patients with osteoporosis before and after treatment with daily injections of 400 U of recombinant, human parathyroid hormone 1-34 [PTH(1-34)]. Two groups of patients were studied. The first group was comprised of 8 men with an average age 49 years. They were treated with PTH for 18 months. The second group was comprised of 8 postmenopausal women with an average age 54 years. They were treated with PTH for 36 months. The women had been and were maintained on hormone replacement therapy for the duration of PTH treatment. Patients were supplemented to obtain an average daily intake of 1500 mg of elemental calcium and 100 IU of vitamin D. The biopsy specimens were subjected to routine histomorphometric analysis and microcomputed tomography (CT). Cancellous bone area was maintained in both groups. Cortical width was maintained in men and significantly increased in women. There was no increase in cortical porosity. There was a significant increase in the width of bone packets on the inner aspect of the cortex in both men and women. This was accompanied by a significant decrease in eroded perimeter on this surface in both groups. Micro-CT confirmed the foregoing changes and, in addition, revealed an increase in connectivity density, a three dimensional (3D) measure of trabecular connectivity in the majority of patients. These findings indicate that daily PTH treatment exerts anabolic action on cortical bone in patients with osteoporosis and also can improve cancellous bone microarchitecture. The results provide a structural basis for the recent demonstration that PTH treatment reduces the incidence of osteoporosis-related fractures.
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Huesos/patología , Osteoporosis Posmenopáusica/patología , Osteoporosis/patología , Hormona Paratiroidea/uso terapéutico , Fragmentos de Péptidos/uso terapéutico , Densidad Ósea , Huesos/efectos de los fármacos , Esquema de Medicación , Femenino , Humanos , Ilion/efectos de los fármacos , Ilion/patología , Masculino , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Osteoporosis/fisiopatología , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/fisiopatología , Hormona Paratiroidea/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , Tomografía Computarizada por Rayos X/métodosRESUMEN
We recently demonstrated that suppressed bone remodeling allows microdamage to accumulate and causes reductions in some mechanical properties. However, in our previous study, 1 year treatment with high-dose etidronate (EHDP) did not increase microdamage accumulation in most skeletal sites of dogs in spite of complete remodeling suppression and the occurrence of spontaneous fractures of ribs and/or thoracic spinous processes. This study evaluates the effects of EHDP on microdamage accumulation and biomechanical properties before fractures occur. Thirty-six female beagles, 1-2 years old, were treated daily for 7 months with subcutaneous injections of saline vehicle (CNT) or EHDP at 0.5 (E-low) or 5 mg/kg per day (E-high). After killing, bone mineral measurement, histomorphometry, microdamage analysis, and biomechanical testing were performed. EHDP treatment suppressed intracortical and trabecular remodeling by 60%-75% at the lower dose, and by 100% at the higher dose. Osteoid accumulation caused by a mineralization deficit occurred only in the E-high group, and this led to a reduction of mineralized bone mass. Microdamage accumulation increased significantly by two- to fivefold in the rib, lumbar vertebra, ilium, and thoracic spinous process in E-low, and by twofold in the lumbar vertebra and ilium in E-high. However, no significant increase in damage accumulation was observed in ribs or thoracic spinous processes in E-high where fractures occur following 12 months of treatment. Mechanical properties of lumbar vertebrae and thoracic spinous processes were reduced significantly in both E-low and E-high. These findings suggest that suppression of bone remodeling by EHDP allows microdamage accumulation, but that osteoid accumulation reduces production of microdamage.