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1.
Am J Hum Biol ; : e24130, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38979712

RESUMEN

PURPOSE: Bone mineral density (BMD) measured with dual x-ray absorptiometry (DXA) is the clinical standard for the diagnosis of osteoporosis and prediction of bone fracture risk. In the aging skeleton, osteoporosis is often concomitantly present with degenerative joint disease (DJD). METHODS: In this study, we evaluated tissue-level changes in the differentially loaded concave (CC) and convex (CV) sides of the lumbar spine in a sample of postmenopausal women with scoliosis. We used a cumulative degeneration score to assess osteophyte formation, the severity of sclerotic morphology, and marrow changes as markers of DJD in the lumbar spine and examined the correlation between markers of DJD and BMD. RESULTS: More severe osteophyte growth and sclerosis were present on the CC side of the spine. The degenerative score (DS) was higher on the CC side of the lumbar spine compared with the CV side. While CC BMD was positively correlated with CC DS and marrow, CV DS was not correlated with CV BMD. Marrow changes were correlated with DS on the CC lumbar spine. CONCLUSION: These results highlight the importance of mechanoadaptive as well as broader inflammatory processes in the manifestation of degenerative changes and local mineral deposition at the lumbar spine. DXA-based BMD measurement of osteoporosis need to be contextualized within the biomechanical and degenerative conditions of a joint rather than using a strict threshold cutoff.

2.
Bone ; 160: 116421, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35429657

RESUMEN

Inhalant use disorder is a psychiatric condition characterized by repeated deliberate inhalation from among a broad range of household and industrial chemical products with the intention of producing psychoactive effects. In addition to acute intoxication, prolonged inhalation of fluorinated compounds can cause skeletal fluorosis (SF). We report a young woman referred for hypophosphatasemia and carrying a heterozygous ALPL gene variant (c.457T>C, p.Trp153Arg) associated with hypophosphatasia, the heritable metabolic bone disease featuring impaired skeletal mineralization, who instead suffered from SF. Manifestations of her SF included recurrent articular pain, axial osteosclerosis, elevated bone mineral density, maxillary exostoses, and multifocal periarticular calcifications. SF was suspected when a long history was discovered of 'huffing' a computer cleaner containing 1,1-difluoroethane. Investigation revealed markedly elevated serum and urine levels of F-. Histopathology and imaging techniques including backscattered electron mode scanning electron microscopy, X-ray microtomography, energy dispersive and wavelength dispersive X-ray emission microanalysis, and polarized light microscopy revealed that her periarticular calcifications were dystrophic deposition of giant pseudo-crystals of francolite, a carbonate-rich fluorapatite. Identifying unusual circumstances of F- exposure is key for diagnosing non-endemic SF. Increased awareness of the disorder can be lifesaving.


Asunto(s)
Enfermedades Óseas Metabólicas , Calcinosis , Hipofosfatasia , Osteoartritis , Osteosclerosis , Fosfatasa Alcalina/genética , Femenino , Humanos , Hidrocarburos Fluorados , Hipofosfatasia/genética , Osteosclerosis/inducido químicamente , Osteosclerosis/diagnóstico por imagen
3.
Endocr Pract ; 19(3): 414-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23337159

RESUMEN

OBJECTIVE: Several studies have shown that patients with end-stage liver disease (ESLD) have lower bone mineral density (BMD) and a higher prevalence of osteoporosis compared to an age-matched population. Hyperinsulinemia and insulin resistance are typically associated with increased BMD. We hypothesized that patients with nonalcoholic steatohepatitis (NASH) and underlying insulin resistance may have higher BMD than patients with cirrhosis from other causes. METHODS: We performed a retrospective chart review of patients with ESLD who underwent liver transplant evaluation at Ochsner Clinic Foundation and had a BMD study as part of initial work up and compared BMD values of patients diagnosed with NASH to patients with cirrhosis due to other causes. Patients were categorized into 3 groups based on the etiology of their liver disease as NASH, alcoholic cirrhosis, or viral hepatitis C or B (HCV/HBV). RESULTS: A total of 63 patients met the study inclusion criteria, including 15 with NASH, 17 with alcoholic cirrhosis, and 31 with HCV/HBV. The overall prevalence rates of osteopenia and osteoporosis were 44% and 12%, respectively. BMD values were higher in the NASH group than the HCV/HBV group at lumbar spine, total hip, and femoral neck (P = .01, .03, and .02, respectively). There were no statistical differences in BMD values between NASH and alcoholic cirrhosis groups at any site. CONCLUSIONS: We found a high prevalence of low BMD among patients with ESLD awaiting liver transplantation. NASH patients had higher BMDs than HCV/HBV patients. The effects of NASH and insulin resistance on bone are complex and should be examined further.


Asunto(s)
Densidad Ósea/fisiología , Hígado Graso/fisiopatología , Hepatopatías/fisiopatología , Trasplante de Hígado , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Bone ; 46(4): 929-34, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20060078

RESUMEN

Reduced osteoblast function is a primary defect in glucocorticoid-induced osteoporosis (GIO), and is reflected by decreased biochemical markers of bone formation, such as serum osteocalcin (OC) and procollagen type I N-terminal propeptide (PINP). This analysis compared the effects of teriparatide and alendronate on OC and PINP in patients with GIO. In a double-blind study, women (N=159) and men (N=38) with GIO were randomized to either teriparatide 20 mug/day by subcutaneous injection or to alendronate 10 mg/day orally. OC and PINP were measured in fasting-state serum samples obtained at baseline and at 1, 6, 18, and 36 months. Baseline bone formation markers were below the reference interval (low) in 33% of patients for OC and in 4% of patients for PINP. On teriparatide therapy, the median OC and PINP levels increased by 92% and 108%, respectively, and this resulted in only 12% and 1% of patients being low at 6 months. On alendronate therapy, the median OC and PINP levels decreased by 40% and 53%, respectively, and this resulted in 68% and 34% of patients being low at 6 months. We conclude that bone formation as determined by surrogate markers was increased in teriparatide-treated patients with GIO and decreased in alendronate-treated patients with GIO.


Asunto(s)
Alendronato/uso terapéutico , Glucocorticoides/efectos adversos , Osteogénesis/fisiología , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Teriparatido/uso terapéutico , Adulto , Anciano , Biomarcadores/sangre , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Conservadores de la Densidad Ósea/uso terapéutico , Distribución de Chi-Cuadrado , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteocalcina/sangre , Osteogénesis/efectos de los fármacos , Osteoporosis/inducido químicamente , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Resultado del Tratamiento
5.
Bone ; 46(4): 935-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20060081

RESUMEN

The purpose of this post hoc analysis was to determine whether baseline concentrations or early changes in serum bone turnover markers were correlated with changes in bone mineral density (BMD) at 18 months in patients with glucocorticoid-induced osteoporosis (GIO) treated with teriparatide (n=80; 20 mug/day) or alendronate (n=77; 10 mg/day). Bone markers included type I collagen N-terminal propeptide (PINP), type I collagen C-terminal propeptide (PICP), bone alkaline phosphatase (bone ALP), and cross-linked C-telopeptide of type I collagen (Sbeta-CTX). The relationship between baseline and early changes in markers and the 18-month changes in lumbar spine (LS) and femoral neck (FN) BMD was evaluated using Spearman correlation analysis. In the teriparatide group, increases in LS and FN BMD at 18 months were not significantly correlated with baseline marker concentrations (P>0.05) but were correlated with the increases in PINP at 1 and 6 months (P<0.05). In the alendronate group, the increase in FN BMD at 18 months was positively correlated with baseline marker concentrations (P<0.05) and negatively correlated with change in PINP and Sbeta-CTX at 1 and 6 months. In addition, in the alendronate group, the increase in LS BMD was negatively correlated with change in Sbeta-CTX at 1 month (P<0.05). Increases in BMD at the spine and hip were independent of baseline bone turnover in the teriparatide group, while increases in hip BMD were dependent on baseline bone turnover in the alendronate group. With both therapies, early changes in some bone turnover markers were correlated with 18-month gains in BMD in patients with GIO.


Asunto(s)
Alendronato/uso terapéutico , Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Glucocorticoides/efectos adversos , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Teriparatido/uso terapéutico , Fosfatasa Alcalina/sangre , Análisis de Varianza , Biomarcadores/sangre , Densidad Ósea/fisiología , Remodelación Ósea/fisiología , Colágeno Tipo I/sangre , Método Doble Ciego , Cuello Femoral/efectos de los fármacos , Cuello Femoral/metabolismo , Humanos , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/metabolismo , Osteoporosis/inducido químicamente , Fragmentos de Péptidos/sangre , Péptidos/sangre , Procolágeno/sangre
6.
Ochsner J ; 10(1): 13-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21603348

RESUMEN

PURPOSE: To determine whether a correlation between ABCC6 mutations and ocular phenotypic expressions exists. METHODS: In this study, 28 relatives of a consultand with known pseudoxanthoma elasticum were recruited for evaluation of the ocular manifestations of the disease, including peau d'orange appearance, angioid streaks, choroidal neovascular membranes, peripapillary atrophy, and retinal drusen. Comprehensive eye examinations were documented for all patients, who were then evaluated for the presence of known mutations in the aforementioned ABCC6 gene. RESULTS: Statistically significant correlations were noted between the gene and peau d'orange appearance (P  =  0.0016), angioid streaks (P < 0.0001), and choroidal neovascular membranes (P  =  0.0016). CONCLUSIONS: A statistically significant association was documented between the R39G mutation of the ABCC6 protein and 3 of 6 known manifestations of pseudoxanthoma elasticum. Although mutations of this gene are clearly associated with angioid streaks, the mechanism by which the transporter affects development of this pathology is speculative.

8.
Bone ; 45(2): 193-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19303956

RESUMEN

The sub-segmental analysis of dual energy X-ray absorptiometry (DXA) scans from scoliotic vertebrae has established that there are differences in bone mass between the concave and convex sides of the vertebrae. Furthermore, these differences persisted in patients with low bone mass and were related to the geometry and applied loads, suggesting that this is a good model of bone adaptation in response to external stimuli. The goal of this study was to characterize the response of the human scoliotic spine to anti-resorptive treatments and estrogen withdrawal on the concave and convex sides of the spine. A total of 576 vertebrae (199 no treatment, 214 bisphosphonate, 69 estrogen and 94 estrogen withdrawal) were analyzed from 167 postmenopausal, Caucasian women. An analysis of variance (ANOVA) was used in conjunction with post-hoc Tukey tests to examine the effects of concavity, treatment group, and age. We found that the average change in BMD per year was greater than zero on the concave and convex sides with the exception of the estrogen withdrawal group. Discontinuing estrogen therapy caused patients to maintain bone mass on the concave side, but lose substantial bone density on the convex side. A differential response was also observed with respect to age. Patients younger than 60 exhibited a decrease in total BMD per year concomitant with a small degree of straightening, while those who were 60 or over demonstrated an increase in bone mass and a slight increase in the deformity. Based on these data, it is clear that the differences in BMD between the concave and convex sides of the vertebrae are not simply a result of the deformity, but more likely due to bone accretion. Further study is needed to elucidate the relationship between biomechanical forces and the adaptive response in the spine as a function of time.


Asunto(s)
Densidad Ósea/fisiología , Resorción Ósea/tratamiento farmacológico , Difosfonatos/uso terapéutico , Estrógenos/uso terapéutico , Vértebras Lumbares/fisiopatología , Escoliosis/tratamiento farmacológico , Escoliosis/fisiopatología , Adulto , Densidad Ósea/efectos de los fármacos , Resorción Ósea/complicaciones , Difosfonatos/farmacología , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/efectos de los fármacos , Persona de Mediana Edad , Radiografía , Escoliosis/complicaciones , Escoliosis/diagnóstico por imagen , Factores de Tiempo
9.
Curr Med Res Opin ; 24(3): 807-13, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18254988

RESUMEN

OBJECTIVE: To evaluate the relationship between bone mass and risk of breast cancer and to determine the effect of raloxifene therapy on breast cancer incidence in women categorized by bone mass into low bone mass and osteoporosis subgroups. DESIGN: In this post hoc analysis, data were analyzed from the Multiple Outcomes of Raloxifene Evaluation (MORE) trial, enrolling postmenopausal women with low bone mass (N = 7705), and the Continuing Outcomes Relevant to Evista (CORE) trial, a follow-up to MORE enrolling 4011 MORE participants. Total follow-up was for up to 8 years. Women with a total hip bone mineral density (BMD) T-score < -1 to > -2.5 or T-score < or = -2.5 (referent, NHANES III database) were classified as having low bone mass or osteoporosis, respectively. Women with a pre-existing vertebral fracture were considered as having osteoporosis irrespective of BMD T-score. Analyses were performed for invasive breast cancers and invasive estrogen-receptor (ER) positive breast cancers. RESULTS: Women with low bone mass (N = 3829) had a twofold higher incidence of invasive ER-positive breast cancer than those with osteoporosis (N = 3836) (HR 2.13, 95% CI 1.12-4.03). The incidence of all invasive breast cancers did not differ significantly between the bone mass groups. The incidences of invasive and invasive ER-positive breast cancers were 65-78% lower in women assigned raloxifene versus placebo in both the low bone mass and osteoporosis groups (p < 0.05). CONCLUSIONS: In this post hoc analysis of postmenopausal women participating in MORE and CORE, bone mass was a predictor of invasive ER-positive breast cancer. Raloxifene treatment reduced the risk of invasive and invasive ER-positive breast cancers in women with low bone mass and those with osteoporosis. Since participants were older postmenopausal women with low bone mass, whether these findings can be generalized to other postmenopausal women is unclear.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/prevención & control , Carcinoma Ductal de Mama/epidemiología , Carcinoma Ductal de Mama/prevención & control , Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Anciano , Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/química , Neoplasias de la Mama/fisiopatología , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/fisiopatología , Femenino , Fémur/fisiopatología , Estudios de Seguimiento , Humanos , Incidencia , Vértebras Lumbares/fisiopatología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Receptores de Estrógenos/análisis , Factores de Riesgo , Estados Unidos/epidemiología
10.
Ochsner J ; 7(2): 52-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-21603515

RESUMEN

The dual purpose of this process paper is to describe the implementation of an intensive insulin infusion program against multiple barriers, despite the increasing evidence in the literature supporting glycemic control, and to report the glucose outcomes. Traditional hyperglycemic management has been done either by subcutaneous sliding scale or intravenous insulin infusions based on absolute glucose numbers. A review of the literature, with particular evidence within the cardiothoracic surgical (CTS) population, has shown significant deleterious effects of even mild hyperglycemia.Increasing evidence supporting prevention of hyperglycemia, along with an unsatisfactory review of current methods used in-house, prompted the initiation of a pilot program to improve current methods utilizing insulin therapy. A multidisciplinary committee was formed consisting of the director of the intensive care unit, a dietician, a nursing unit director, a charge nurse, an endocrinologist, and two endocrinology nurse practitioners with extensive experience in intensive insulin therapy, including continuous subcutaneous insulin infusion. A review of literature was performed to evaluate available data and intravenous insulin infusion algorithms used by published authors. The CTS population was chosen as well as the intensive care unit. Nursing barriers in particular were extensive, and the use of a velocity driven insulin protocol required didactic instruction as well as individual reinforcement. All education, algorithm development, and oversight of patients were primarily performed by the nurse practitioners with immediate endocrinologist availability if needed. A review of glucose results indicated a significant reduction in hyperglycemia with a decrease in hypoglycemia and facilitated transition to subcutaneous therapy when necessary.

12.
Osteoporos Int ; 16(12): 1857-63, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15999291

RESUMEN

Nearly one-third of all women and one-sixth of all men over age 65 have osteoporosis, and this condition is often accompanied by lumbar scoliosis. Previous work has shown that, in a group of postmenopausal women with scoliosis and osteoporosis, both the bone mineral content (BMC) and bone mineral density (BMD) were greater on the concave side than the convex side. The goal of this study was to examine the structure-function relationships in the spines of patients with low bone mass and scoliosis using a patient-specific biomechanical model. We compared the percent change in BMC and the percent change in BMD with axial force, F(a), shear force, F(s), moment, M, local curvature, theta(rel), and the patient's age, A. We found that the percent change in BMC depended on the applied moment and the local curvature. The same dependence was observed for the percent change in BMD, but in this case, the shear force was also significantly inversely correlated. A population with femoral neck BMD with a T-score greater than -2.0 was similarly evaluated and yielded similar results. The percent change in BMD was related to M, theta(rel), A and negatively to the shear force. These results indicate that the osteoporotic spine is still able to respond to changes in the mechanical environment and provides a useful comparison between patients with osteoporosis and those with normal bone mass. In addition, this model may be a useful tool for the in vivo assessment of bone density changes in response to mechanical stimuli and drug treatments.


Asunto(s)
Densidad Ósea/fisiología , Vértebras Lumbares/fisiopatología , Osteoporosis Posmenopáusica/fisiopatología , Escoliosis/fisiopatología , Absorciometría de Fotón/métodos , Anciano , Fenómenos Biomecánicos , Femenino , Cuello Femoral , Humanos , Vértebras Lumbares/diagnóstico por imagen , Modelos Biológicos , Análisis de Regresión , Estrés Mecánico
14.
Spine (Phila Pa 1976) ; 30(4): 434-9, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-15706341

RESUMEN

STUDY DESIGN: In this study, we elucidated the bone quantity and distribution in lumbar spines of a group of 176 postmenopausal women (average age 72 years) with scoliosis. SUMMARY OF BACKGROUND DATA: Adolescent idiopathic scoliosis is associated with a low bone mineral density, but the bone mineral density in adult lumbar scoliosis has not been well-characterized. METHODS: Dual-energy x-ray absorptiometry analysis of the femoral neck and lumbar spines of 176 postmenopausal women were used to assess the bone mineral density and bone mineral content at both anatomic sites. Subsegmental analysis was used to determine the bone distribution within the lumbar vertebrae. RESULTS: The lumbar spine bone mass was greater than the femoral neck as evidenced by the average lumbar spine and femoral neck T-scores, -0.493 and -1.81, and Z-scores, 1.70 and 0.12, respectively. There was also a significant correlation between the lumbar spine bone mineral density and femoral neck bone mineral density (r2 = 0.24, P < 0.0001). Individual analysis of 655 vertebrae after bisection and trisection showed that the bone mineral density of the concave side was 15% to 20% higher than the convex, and the difference between the 2 sides was at least as great for patients with low femoral neck bone mineral density as those with high femoral neck bone mineral density. CONCLUSIONS: The quantity and distribution of bone in adult scoliosis is markedly different from adolescent scoliosis. The lumbar spine bone mass is much greater than the femoral neck, and the concave side bone mass is greater than the convex. Finally, subsegmental vertebral dual-energy x-ray absorptiometry analysis may have wider applications in research and clinical settings.


Asunto(s)
Densidad Ósea , Vértebras Lumbares/diagnóstico por imagen , Escoliosis/diagnóstico por imagen , Absorciometría de Fotón/métodos , Anciano , Anciano de 80 o más Años , Densidad Ósea/fisiología , Femenino , Humanos , Vértebras Lumbares/fisiología , Persona de Mediana Edad , Posmenopausia/fisiología , Escoliosis/fisiopatología
15.
J Clin Endocrinol Metab ; 89(2): 581-4, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14764765

RESUMEN

A patient with a large prolactinoma developed a metastatic islet cell tumor secreting pancreatic polypeptide. Dopamine agonist drugs reduced the prolactin levels to normal, caused a 7-fold decrease in the pancreatic polypeptide levels, and inhibited the liver metastases. Elevated chromogranin A levels also normalized on the higher doses of bromocriptine. Dopamine receptors are found in many endocrine tissues, and the expression of dopamine-2 receptor on endocrine tumors establishes the potential for response to dopamine agonist treatment. The relatively benign risk profile of dopaminergic agents makes further testing of these drugs to treat neuroendocrine tumors a worthwhile endeavor.


Asunto(s)
Adenoma de Células de los Islotes Pancreáticos/tratamiento farmacológico , Adenoma de Células de los Islotes Pancreáticos/metabolismo , Bromocriptina/uso terapéutico , Agonistas de Dopamina/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Polipéptido Pancreático/antagonistas & inhibidores , Adenoma de Células de los Islotes Pancreáticos/diagnóstico , Bromocriptina/administración & dosificación , Cromogranina A , Cromograninas/sangre , Agonistas de Dopamina/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Neoplasias Primarias Múltiples/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , Prolactinoma/diagnóstico , Prolactinoma/tratamiento farmacológico
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