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1.
Osteoporos Int ; 32(7): 1313-1320, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33438038

RESUMEN

Prevention of early menopausal bone loss may reduce the future burden of osteoporosis. In this modelling exercise, an osteoporosis prevention strategy involving 5-year infusions of zoledronic acid, beginning early in menopause, reduced long-term fracture risk and the proportion of aging women with femoral neck densitometric osteoporosis. This strategy warrants further evaluation. INTRODUCTION: Preventing early menopausal bone loss may substantially reduce the future burden of osteoporosis. We modelled the effects of infrequent zoledronic acid infusions on long-term fracture risk. METHODS: Data from the Canadian Multicentre Osteoporosis Study (CaMos) were used to determine the expected natural history of femoral neck areal bone mineral density (BMD) and fracture risk (using FRAX®) from ages 50-80 for women with no antiresorptive drug exposures. We modelled the effects of three infusions of zoledronic acid (at ages 50, 55, 60) on long-term fracture risk, assuming this intervention would preserve BMD until age 65 years, followed by losses mirroring early menopausal BMD loss. RESULTS: At age 65, untreated women and zoledronic acid recipients had expected mean (SD) femoral neck T-scores of - 1.5(1.0) and - 0.8(1.0), 10-year major osteoporotic fracture (MOF) risks of 9.8%(5.0) and 8.0%(3.7) and hip fracture risks of 1.7%(2.4) and 0.8%(1.2), respectively. At age 80, untreated women and zoledronic acid recipients had expected femoral neck T-scores of - 1.9(0.9) and - 1.4(0.9), MOF risks of 17.9%(8.2) and 14.9%(6.4) and hip fracture risks of 6.3%(6.2) and 4.4%(4.5), respectively. The expected proportion of women with femoral neck T-score ≤ - 2.5 was 14.9% for untreated women and 3.8% for zoledronic acid recipients at age 65, increasing to 28.1% and 12.0%, respectively, at age 80. Numbers-needed-to-treat to prevent one case of densitometric osteoporosis were 9 at age 65 and 5 at age 80. CONCLUSION: Infrequent infusions of zoledronic acid, initiated early in menopause, are expected to reduce long-term fracture risk and result in a substantial reduction in the proportion of women with densitometric osteoporosis after age 65.


Asunto(s)
Densidad Ósea , Fracturas Osteoporóticas , Anciano , Anciano de 80 o más Años , Canadá , Estudios de Factibilidad , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/prevención & control , Medición de Riesgo
2.
Osteoporos Int ; 31(6): 1145-1153, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32034452

RESUMEN

We examined the underlying relationship between fracture risk factors and their imminent risk. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher imminent fracture risk. Past year falls indirectly predicted imminent risk through physical functioning and general health. INTRODUCTION: This study aimed to examine direct and indirect effects of several factors on imminent (1 year) fracture risk. METHODS: Data from women age 65 and older from population-based Canadian Multicentre Osteoporosis Study were used. Predictors were identified from study years 5 and 10, and imminent fracture data (1-year fracture) came from years 6 and 11 (year 5 predicts year 6, year 10 predicts year 11). A structural equation model (SEM) was used to test the theoretical construct. General health and physical functioning were measured as latent variables using items from the 36-Item Short Form Health Survey (SF-36) and bone mineral density (BMD) T-score was a latent variable based on observed site-specific BMD data (spine L1-L4, femoral neck, total hip). Observed variables were fractures and falls. Model fit was evaluated using root mean square error of approximation (RMSEA), Tucker Lewis index (TLI), and comparative fit index (CFI). RESULTS: The analysis included 3298 women. Model fit tests showed that the SEM fit the data well; χ2(172) = 1122.10 < .001, RMSEA = .03, TLI = .99, CFI = .99. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher risk of fracture in the subsequent year (p < .001). Past year falls had a statistically significant but indirect effect on imminent fracture risk through physical functioning and general health (p < .001). CONCLUSIONS: We found several direct and indirect pathways that predicted imminent fracture risk in elderly women. Future studies should extend this work by developing risk scoring methods and defining imminent risk thresholds.


Asunto(s)
Densidad Ósea , Fracturas Óseas/epidemiología , Osteoporosis/epidemiología , Anciano , Canadá/epidemiología , Estudios de Cohortes , Femenino , Humanos , Modelos Teóricos , Factores de Riesgo
3.
Osteoporos Int ; 30(8): 1635-1644, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31069440

RESUMEN

Little is known about the association between health-related quality of life (HRQOL) and osteoporosis in the absence of fracture, and how HRQOL may change over time. This study provides evidence of substantially reduced HRQOL in women and men with self-reported and/or BMD-confirmed osteoporosis, even in the absence of fragility fracture. INTRODUCTION: Fragility fractures have a detrimental effect on the health-related quality of life (HRQOL) of those with osteoporosis. Less is known about the association between HRQOL and osteoporosis in the absence of fracture. METHODS: Canadian Multicentre Osteoporosis Study participants completed the SF-36, a detailed health questionnaire and measures of bone mineral density (BMD) at baseline and follow-up. We report the results of participants ≥ 50 years with 10-year follow-up. Self-reported osteoporosis at baseline and BMD-based osteoporosis at follow-up were ascertained. Multivariable linear regression models were developed for baseline SF-36 domains, component summaries, and change over time, adjusting for relevant baseline information. RESULTS: Baseline data were available for 5266 women and 2112 men. Women in the osteoporosis group had substantially lower SF-36 baseline scores, particularly in the physically oriented domains, than those without osteoporosis. A similar but attenuated pattern was evident for the men. After 10-year follow-up (2797 women and 1023 men), most domain scores dropped for women and men regardless of osteoporosis status, with the exception of mentally-oriented ones. In general, a fragility fracture was associated with lower SF-36 scores and larger declines over time. CONCLUSIONS: This study provides evidence of substantially reduced HRQOL in women and men with self-reported and/or BMD-confirmed osteoporosis, even in the absence of fragility fracture. HRQOL should be thoroughly investigated even prior to fracture, to develop appropriate interventions for all stages of the disease.


Asunto(s)
Osteoporosis/rehabilitación , Calidad de Vida , Anciano , Anciano de 80 o más Años , Densidad Ósea/fisiología , Canadá , Femenino , Encuestas Epidemiológicas , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Osteoporosis/fisiopatología , Osteoporosis Posmenopáusica/fisiopatología , Osteoporosis Posmenopáusica/rehabilitación , Fracturas Osteoporóticas/fisiopatología , Fracturas Osteoporóticas/rehabilitación , Psicometría , Autoinforme , Factores Socioeconómicos , Encuestas y Cuestionarios
4.
J Musculoskelet Neuronal Interact ; 13(4): 470-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24292617

RESUMEN

OBJECTIVES: Our objective was to study changes in calcium and vitamin D intakes over time, and their cross-sectional and longitudinal associations with bone mineral density (BMD). METHODS: We followed 9382 women and men aged ≥25 and 899 aged 16-24, for 10 and 2 years respectively. RESULTS: Calcium and vitamin D intakes increased over time in adults, but decreased in women aged 16-18. The increased intakes in adults were largely attributable to the increased use of calcium and/or vitamin D supplements. Both the percentage of supplement users and average dose among users increased over time. There was nevertheless a high prevalence of calcium and vitamin D intake below the estimated average requirement. At baseline, higher calcium and vitamin D intakes were associated with higher total hip and femoral neck BMD in young men, and cumulatively high levels of calcium and vitamin D intakes over time contributed to better BMD maintenance at lumbar spine and hip sites in adult women. CONCLUSIONS: Although total intakes, particularly of vitamin D, frequently fell below the Institute of Medicine recommendations despite an increase over time in supplement use, we found some positive associations between total calcium and vitamin D intake and bone health.


Asunto(s)
Densidad Ósea/fisiología , Calcio de la Dieta/administración & dosificación , Suplementos Dietéticos , Osteoporosis/diagnóstico por imagen , Vitamina D/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Canadá , Femenino , Cuello Femoral/diagnóstico por imagen , Cadera/diagnóstico por imagen , Humanos , Estudios Longitudinales , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía
5.
Osteoarthritis Cartilage ; 19(4): 375-80, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21251987

RESUMEN

OBJECTIVE: Glucosamine is commonly used for the treatment of osteoarthritis. It is available as an over the counter preparation and also as a prescription pharmaceutical. There is concern from animal experiments that glucosamine may alter glucose metabolism through the hexosamine biosynthetic pathway. The objective of this systematic review is to determine if exogenous glucosamine adversely affects glucose metabolism in humans. This review does not separate out the effects on glucose metabolism of the various glucosamine preparations. METHOD: An English-language literature search of MEDLINE, EMBASE and EBM Reviews (1950-February 2009) was conducted. The bibliographies of selected papers were manually searched for additional references. Two reviewers independently analyzed studies for quality and content using a standardized data extraction form. RESULTS: Eleven studies were included. Six studies were randomized controlled trials and the remaining five were prospective studies with or without controls. Four of the studies found decreased insulin sensitivity or increased fasting glucose in subjects taking glucosamine. Three of these were clinical studies using oral glucosamine. Studies that included subjects with baseline impaired glucose tolerance or insulin resistance were more likely to detect an effect on glucose metabolism than studies without such subjects. CONCLUSION: Clinical studies, including three using oral glucosamine, have provided mixed evidence about the effect of exogenous glucosamine on glucose metabolism in humans. Therefore, more studies are needed, particularly including subjects at high risk for impairments in glucose homeostasis, before a definite conclusion can be made.


Asunto(s)
Glucosamina/uso terapéutico , Glucosa/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Glucosamina/administración & dosificación , Humanos , Resistencia a la Insulina
6.
Osteoporos Int ; 22(3): 789-96, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20683706

RESUMEN

UNLABELLED: Canadian women over 50 years old were studied over a 10-year period to see if those who sustained a fracture (caused by minimal trauma) were receiving the recommended osteoporosis therapy. We found that approximately half of these women were not being treated, indicating a significant care gap in osteoporosis treatment. INTRODUCTION: Prevalent fragility fracture strongly predicts future fracture. Previous studies have indicated that women with fragility fractures are not receiving the indicated treatment. We aimed to describe post fracture care in Canadian women using a large, population-based prospective cohort that began in 1995-1997. METHODS: We followed 5,566 women over 50 years of age from across Canada over a period of 10 years in the Canadian Multicentre Osteoporosis Study. Information on medication use and incident clinical fragility fractures was obtained during a yearly questionnaire or interview and fractures were confirmed by radiographic/medical reports. RESULTS: Over the 10-year study period, 42-56% of women with yearly incident clinical fragility fractures were not treated with an osteoporosis medication. During year 1 of the study, 22% of the women who had experienced a fragility fracture were on treatment with a bisphosphonate and 26% were on hormone therapy (HT). We were not able to differentiate HT use for menopause symptoms vs osteoporosis. Use of bisphosphonate therapy increased over time; odds ratio (OR) for use at year 10 compared to use at year 1 was 3.65 (95% confidence interval (CI) 1.83-7.26). In contrast, HT use declined, with an OR of 0.07 (95%CI 0.02-0.24) at year 10 compared to year 1 of the study. CONCLUSION: In a large population-based cohort study, we found a therapeutic care gap in women with osteoporosis and fragility fractures. Although bisphosphonate therapy usage improved over time, a substantial gap remains.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Fracturas Espontáneas/prevención & control , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/prevención & control , Pautas de la Práctica en Medicina/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Densidad Ósea , Canadá/epidemiología , Atención a la Salud/tendencias , Terapia de Reemplazo de Estrógeno , Femenino , Fracturas Espontáneas/epidemiología , Adhesión a Directriz , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/epidemiología , Estudios Prospectivos
7.
Osteoporos Int ; 20(5): 703-14, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-18802659

RESUMEN

UNLABELLED: Using prospective data from the Canadian Multicentre Osteoporosis Study (CaMos), we compared health utilities index (HUI) scores after 5 years of follow-up among participants (50 years and older) with and without incident clinical fractures. Incident fractures had a negative impact on HUI scores over time. INTRODUCTION: This study examined change in health-related quality of life (HRQL) in those with and without incident clinical fractures as measured by the HUI. METHODS: The study cohort was 4,820 women and 1,783 men (50 years and older) from the CaMos. The HUI was administered at baseline and year 5. Participants were sub-divided into incident fracture groups (hip, rib, spine, forearm, pelvis, other) and were compared with those without these fractures. The effects of both time and fracture type on HUI scores were examined in multivariable regression analyses. RESULTS: Men and women with hip fractures, compared to those without, had lower HUI measures that ranged from -0.05 to -0.25. Both women and men with spine fractures had significant deficits on the pain attributes (-0.07 to -0.12). In women, self-care (-0.06), mobility and ambulation (-0.05) were also negatively impacted. Women with rib fractures had deficits similar to women with spine fractures, and these effects persisted over time. In men, rib fractures did not significantly affect HUI scores. Pelvic and forearm fractures did not substantially influence HUI scores. CONCLUSION: The HUI was a sensitive measure of HRQL change over time. These results will inform economic analyses evaluating osteoporosis therapies.


Asunto(s)
Fracturas Óseas/rehabilitación , Estado de Salud , Calidad de Vida , Actividades Cotidianas , Anciano , Canadá , Femenino , Traumatismos del Antebrazo/etiología , Traumatismos del Antebrazo/rehabilitación , Fracturas Óseas/etiología , Indicadores de Salud , Fracturas de Cadera/etiología , Fracturas de Cadera/rehabilitación , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Huesos Pélvicos/lesiones , Estudios Prospectivos , Fracturas de las Costillas/etiología , Fracturas de las Costillas/rehabilitación , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/rehabilitación , Factores de Tiempo
8.
Biochim Biophys Acta ; 1773(2): 264-72, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17079030

RESUMEN

Joint destruction in arthritis is often associated with high levels of inflammatory cytokines. Previous work has shown that inflammatory conditions can alter the activities of glycosyltransferases that synthesize the glycan chains of glycoproteins, and that these changes in turn can influence the functions of glycoproteins. We therefore examined glycosyltransferases involved in glycoprotein biosynthesis in primary cultures of bovine articular chondrocytes and human chondrocytes isolated from knee cartilage of osteoarthritis patients. Bovine chondrocytes exhibited enzyme activities involved in the synthesis of bi-antennary complex Asn-linked N-glycans, as well as the enzymes involved in the synthesis of GalNAc-Ser/Thr-linked O-glycans with the core 1 structure. Human chondrocytes, in addition, were able to synthesize more complex O-glycans with core 2 structures. TNFalpha was found to induce apoptosis in chondrocytes, and this process was associated with significant changes in lectin binding to chondrocyte cell surface glycans. TGFbeta increased cell proliferation, and had significant effects on cell surface glycosylation in bovine but not in human cells. These cytokine-specific effects were partially correlated with changes in glycosyltransferase activities. Thus, chondrocytes have many of the enzymes necessary for the synthesis of N- and O-glycan chains of glycoproteins. The O-glycosylation pathways and the effects of TNFalpha and TGFbeta on glycosylation differed between bovine and human chondrocytes. These alterations are of potential importance for the regulation of the functions of cell surface receptors on chondrocytes, and for an understanding of the pathophysiology of arthritis.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Anciano , Animales , Bovinos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Condrocitos/citología , Condrocitos/enzimología , Femenino , Glicosilación/efectos de los fármacos , Glicosiltransferasas/metabolismo , Humanos , Etiquetado Corte-Fin in Situ , Lectinas/metabolismo , Masculino , Microscopía Fluorescente , Polisacáridos/biosíntesis
9.
Osteoporos Int ; 19(12): 1733-40, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18629567

RESUMEN

UNLABELLED: In a cluster randomized trial, we evaluated the effect of a multifaceted intervention (directed at both patient and primary care physician) on the rates of testing and treatment of osteoporosis in postmenopausal women within six months of their wrist fracture. Compared to usual care, women in the intervention practices were three times more likely to receive bone mineral density testing and prescribed osteoporosis treatments. INTRODUCTION: Postmenopausal women with wrist fractures are at increased risk of future fragility fractures, yet they frequently do not receive evaluation and treatment for osteoporosis. We set out to evaluate a multifaceted intervention designed to improve management of osteoporosis in older women with recent wrist fractures. METHODS: Cluster randomized trial of 270 women cared for in 119 primary care practices. We recruited postmenopausal women with an acute wrist fracture from the emergency departments of hospitals in southeastern Ontario, Canada. Family practices were randomly assigned to either the intervention or usual care. The intervention consisted of a mailed reminder with a summary of treatment guidelines and letter sent to the primary care physician, in addition to an educational package and letter to the women. The primary outcome was the proportion of women prescribed osteoporosis therapy within 6 months of their fracture. RESULTS: The mean age of women was 69(10.9) years. The intervention increased the proportion of women started on osteoporosis medications (28% vs. 10%) of controls, adjusted OR 3.45, 95% CI, 1.58-7.56, p = 0.002) and the proportion who had a bone mineral density (BMD) test (53.3% vs. 26%) of controls, OR 3.38, 95% CI, 1.83-6.26, p < 0.001). In addition to the intervention, having a female physician was a predictor of increased testing and treatment rates. CONCLUSION: A multifaceted intervention significantly improved rates of osteoporosis treatment and BMD testing in postmenopausal women with wrist fractures.


Asunto(s)
Densidad Ósea/fisiología , Fracturas Óseas/epidemiología , Osteoporosis Posmenopáusica/epidemiología , Traumatismos de la Muñeca/epidemiología , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Femenino , Fracturas Óseas/prevención & control , Humanos , Persona de Mediana Edad , Ontario/epidemiología , Osteoporosis Posmenopáusica/fisiopatología , Osteoporosis Posmenopáusica/terapia , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Atención Primaria de Salud , Calidad de la Atención de Salud , Traumatismos de la Muñeca/prevención & control
10.
J Clin Invest ; 68(3): 792-802, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7276172

RESUMEN

Human blood mononuclear cells exposed to concanavalin A or phytohemagglutinin secrete a soluble factor that arrests the growth of human synovial fibroblastic cells in culture. Once the growth-inhibitory effect is initiated it cannot be reversed by washing the fibroblastic cells, by refeeding with nonconditioned fresh serum-containing medium, by trypsinization, EDTA treatment, or a combination of these procedures. Media from nonstimulated mononuclear cells, fibroblastic cells, or the lectins themselves do not contain similar inhibitory activity that can be detected by the present culture systems. This lectin-dependent, growth-inhibitory activity does not have a cytotoxic effect on the fibroblasts but increases their adhesiveness to plastic or glass surfaces, and the cells tend to assume a less fibroblastic morphology. The growth-inhibitory activity is stable in the cold and is nondialyzable or ultrafilterable, but the activity is rapidly lost at temperature between 60 degrees and 70 degrees C and at pH 2.0. The growth-arrested cells secrete more glycosaminoglycan per cell in the medium and synthesize more cell surface glycosaminoglycan than the controls. However, the increased glycosaminoglycan synthesis cannot be explained as being entirely secondary to a cell density effect as it is also observed when adjustments are made for the differences in growth rates.


Asunto(s)
Glicosaminoglicanos/biosíntesis , Linfocinas/farmacología , Membrana Sinovial/citología , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo , Fibroblastos/efectos de los fármacos , Humanos
11.
Cochrane Database Syst Rev ; (2): CD002946, 2005 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-15846645

RESUMEN

BACKGROUND: Osteoarthritis (OA) is the most common form of arthritis, and it is often associated with significant disability and an impaired quality of life. OBJECTIVES: To review all randomized controlled trials (RCTs) evaluating the effectiveness and toxicity of glucosamine in OA. SEARCH STRATEGY: We searched MEDLINE, PREMEDLINE, EMBASE, AMED, ACP Journal Club, DARE, CDSR, and the CCTR. We also wrote letters to content experts, and hand searched reference lists of identified RCTs and pertinent review articles. All searches were updated in January 2005. SELECTION CRITERIA: Relevant studies met the following criteria: 1) RCTs evaluating the effectiveness and safety of glucosamine in OA, 2) Both placebo controlled and comparative studies were eligible, 3) Both single blinded and double blinded studies were eligible. DATA COLLECTION AND ANALYSIS: Data abstraction was performed independently by two investigators and the results were compared for degree of agreement. Gotzsche's method and a validated tool (Jadad 1996) were used to score the quality of the RCTs. Continuous outcome measures were pooled using standardized mean differences (SMD) as the measure of effect size. Dichotomous outcome measures were pooled using relative risk ratios (RR). MAIN RESULTS: Analysis restricted to eight studies with adequate allocation concealment failed to show benefit of glucosamine for pain and WOMAC function. Collectively, the 20 analyzed RCTs found glucosamine favoured placebo with a 28% (change from baseline) improvement in pain (SMD -0.61, 95% CI -0.95, -0.28) and a 21% (change from baseline) improvement in function using the Lequesne index (SMD -0.51 95% CI -0.96, -0.05). However, the results are not uniformly positive, and the reasons for this remain unexplained. WOMAC pain, function and stiffness outcomes did not reach statistical significance. In the 10 RCTs in which the Rotta preparation of glucosamine was compared to placebo, glucosamine was found to be superior for pain (SMD -1.31, 95% CI -1.99, -0.64) and function using the Lequesne index (SMD -0.51, 95% CI -0.96, -0.05). Pooled results for pain (SMD -0.15, 95% CI -0.35, 0.05) and function using the WOMAC index (SMD 0.03, 95% CI -0.18, 0.25) in those RCTs in which a non-Rotta preparation of glucosamine was compared to placebo did not reach statistical significance. In the four RCTs in which the Rotta preparation of glucosamine was compared to an NSAID, glucosamine was superior in two, and equivalent in two. Two RCTs using the Rotta preparation showed that glucosamine was able to slow radiological progression of OA of the knee over a three year period (SMD 0.24, 95% CI 0.04, 0.43). Glucosamine was as safe as placebo in terms of the number of subjects reporting adverse reactions (RR=0.97, 95% CI, 0.88, 1.08). AUTHORS' CONCLUSIONS: This update includes 20 studies with 2570 patients. Pooled results from studies using a non-Rotta preparation or adequate allocation concealment failed to show benefit in pain and WOMAC function while those studies evaluating the Rotta preparation show that glucosamine was superior to placebo in the treatment of pain and functional impairment resulting from symptomatic OA. WOMAC outcomes of pain, stiffness and function did not show a superiority of glucosamine over placebo for both Rotta and non-Rotta preparations of glucosamine. Glucosamine was as safe as placebo.


Asunto(s)
Glucosamina/uso terapéutico , Osteoartritis/tratamiento farmacológico , Adulto , Método Doble Ciego , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Proc Inst Mech Eng H ; 219(1): 23-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15777054

RESUMEN

Many experimental protocols for investigating articular cartilage mechanics have involved the use of a freeze-thaw cycle for storage or tissue manipulation. It was hypothesized that mechanical properties are altered due to freeze-thaw cycling. The aim of this study, therefore, was to examine the possibility of protocol-induced artefacts in the mechanical properties of porcine articular cartilage specimens related specifically to freeze-thaw events. Twenty-eight osteochondral specimens [14 from the femoral condyles (FCs) and 14 from the patella-femoral (PF) groove] were tested in confined compression before and after being frozen at -20 degrees C for 7 days. The fluid-independent and fluid-dependent mechanical properties (aggregate modulus of the solid phase and the half-life of stress relaxation respectively) were determined and compared. The aggregate modulus decreased by 13.5 per cent and 20.1 per cent for the PF and FC regions respectively (p = 0.002) and the half-life of the stress relaxation at 10 per cent strain decreased by 6.4 per cent and 12.6 per cent for the PF and FC specimens respectively (p = 0.0341). In conclusion, it has been shown that the protocol used, which involved freezing to -20 degrees C and thawing after 7 days, caused artefacts in the mechanical properties of porcine osteochondral specimens. It is suggested that protocols requiring freezing must be critically reviewed to eliminate such artefacts.


Asunto(s)
Cartílago Articular/citología , Cartílago Articular/fisiología , Criopreservación/métodos , Congelación , Mecanotransducción Celular/fisiología , Animales , Fenómenos Biomecánicos/métodos , Elasticidad , Estrés Mecánico , Porcinos
13.
J Bone Miner Res ; 8(11): 1301-9, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8266822

RESUMEN

Anchorage-dependent cultures of a population of cells derived from the outer part of the rat calvaria demonstrated decreased net accumulation of radiolabeled chondroitin sulfate (CS) and hyaluronic acid (HA) per cell as the cell density of the cultures increased. The addition of TGF-beta 1 resulted in large stimulations of the net CS, but not of the net HA, accumulating in the medium at all cell densities and an abolition of the density-dependent effect. These effects were largely due to increases in newly synthesized CS appearing in the medium. Supplementation of the culture media with CS had complex but relatively small effects on the stimulation of the net accumulation of radiolabeled medium CS by TGF-beta 1. The addition of TGF-beta 1 also resulted in a biphasic effect on cell growth that depended on the plating density, but cell growth differences could not account for the marked stimulation of CS synthesis by TGF-beta 1. Experiments with cycloheximide and beta-xyloside and isolation of the intact anionic glycoconjugates (AG) indicated that although synthesis of core protein was the limiting factor in CS synthesis, TGF-beta 1 stimulated the synthesis of CS chain when sufficient beta-xyloside acceptor was available. The overall results suggest that, in this cell system, the action of TGF-beta 1 on the synthesis of the major extracellular AGs is characterized by a relatively specific upregulation of CS proteoglycan (PG) synthesis and an uncoupling of the inhibitory effect of high cell density on CS PG synthesis.


Asunto(s)
Sulfatos de Condroitina/biosíntesis , Ácido Hialurónico/biosíntesis , Cráneo/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Animales , Recuento de Células , Células Cultivadas , Sulfatos de Condroitina/farmacología , Ratas , Cráneo/citología
14.
J Bone Miner Res ; 18(4): 784-90, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12674340

RESUMEN

This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.


Asunto(s)
Densidad Ósea , Osteoporosis/epidemiología , Columna Vertebral/anomalías , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Estudios de Cohortes , Estudios Transversales , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Hipertensión/complicaciones , Cálculos Renales/complicaciones , Masculino , Persona de Mediana Edad , Osteítis Deformante/complicaciones , Osteoporosis/complicaciones
15.
J Am Geriatr Soc ; 30(2): 94-100, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6460054

RESUMEN

The efficacy and the toxicity pattern of D-penicillamine were studied in patients with rheumatoid disease followed up between April 1975 and March 1979. The population of patients was divided into an elderly group (greater than or equal to 60 years old, mean = 65 years) and a younger group (less than 60 years old, mean = 41 years). Patients with classic or definite rheumatoid disease not responsive to nonsteroidal drugs were eligible. The mean durations of disease prior to D-penicillamine therapy were five years in the elderly and seven years in the younger group. Overall, the mean follow-up time was 11 months. The average dosages of D-penicillamine were 461 mg/day in the elderly and 520 mg/day in the younger patients. Results indicated that D-penicillamine was efficacious in 75 per cent of the elderly during all time periods after three months, and in 75 per cent of the younger patients after three months until at least two years. Prior gold-salt therapy did not influence efficacy. Toxicity was significantly greater in the elderly for overall skin rash (P less than 0.01), severe skin rash (P less than 0.01), and marked abnormalities in the ability to taste (P less than 0.05). The incidence of hematologic toxicity was not increased in the elderly compared with the younger patients. Toxicity in either group was not influenced by prior gold-salt therapy. It is concluded that D-penicillamine was equally efficacious in both elderly and younger groups, and that the toxicity patterns were similar except for increased tendencies toward rashes and taste abnormalities in the elderly.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Penicilamina/uso terapéutico , Adulto , Factores de Edad , Anciano , Artritis Reumatoide/sangre , Erupciones por Medicamentos/etiología , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Oro/uso terapéutico , Humanos , Leucopenia/inducido químicamente , Masculino , Persona de Mediana Edad , Penicilamina/efectos adversos , Proteinuria/inducido químicamente , Trastornos del Gusto/inducido químicamente , Factores de Tiempo
16.
Cochrane Database Syst Rev ; (1): CD002946, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11279782

RESUMEN

BACKGROUND: Osteoarthritis (OA) is the most common form of arthritis, and it is often associated with significant disability and an impaired quality of life. OBJECTIVES: To review all randomized controlled trials (RCTs) evaluating the effectiveness and toxicity of glucosamine in osteoarthritis (OA). SEARCH STRATEGY: We searched MEDLINE, Embase, and Current Contents up to November 1999, and the Cochrane Controlled Trials Register. We also wrote letters to content experts, and hand searched reference lists of identified RCTs and pertinent review articles. SELECTION CRITERIA: Relevant studies met the following criteria: 1) RCTs evaluating the effectiveness and safety of glucosamine in OA, 2) Both placebo based and comparative studies were eligible, 3) Both single blinded and double-blinded studies were eligible. DATA COLLECTION AND ANALYSIS: Data abstraction was performed independently by two investigators and the results were compared for degree of agreement. Gotzsche's method and a validated tool (Jadad 1995) were used to score the quality of the RCTs. Continuous outcome measures were pooled using standardized mean differences. Dichotomous outcome measures were pooled using Peto Odds Ratios. MAIN RESULTS: Collectively, the 16 identified RCTs provided evidence that glucosamine is both effective and safe in OA. In the 13 RCTs in which glucosamine was compared to placebo, glucosamine was found to be superior in all RCTs, except one. In the four RCTs in which glucosamine was compared to an NSAID, glucosamine was superior in two, and equivalent in two. REVIEWER'S CONCLUSIONS: Further research is necessary to confirm the long term effectiveness and toxicity of glucosamine therapy in OA. Most of the trials reviewed only evaluated the Rotta preparation of glucosamine sulfate. It is not known whether different glucosamine preparations prepared by different manufacturers are equally effective in the therapy of OA.


Asunto(s)
Glucosamina/uso terapéutico , Osteoartritis/tratamiento farmacológico , Método Doble Ciego , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple Ciego
17.
In Vitro Cell Dev Biol Anim ; 30A(8): 504-11, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7987538

RESUMEN

Current evidence suggests that interactions between the subchondral bone and the articular cartilage of mammalian diarthrodial joints may occur through the action of bone-associated peptide factors. However, there is no suitable organ culture model for studying these interactions. This study defines a long-term tissue culture system where the articular cartilage is coupled to the adjacent subchondral bone obtained from the proximal ends of bovine metacarpals. Autoradiography done over 3 mo., by utilizing [35S]SO4 incorporation into cartilage proteoglycan (PG) and a procedure for cutting non-decalcified bone, demonstrated similar numbers of silver grains over chondrocytes in all cartilage zones, including the bone-cartilage interface. Newly synthesized PG (NSPG) from the cartilage of the "coupled" system over a 3-wk period was primarily of large hydrodynamic size (Kav of 0.34). Comparable bovine articular and nasal cartilage slice systems, incubated for short periods of time, yielded similar and somewhat larger NSPG, respectively. Labeled chondroitin sulphate PG accumulating in the medium of primary chondrocyte monolayer cultures, derived from the cartilage of the coupled system at 0, 1, 2, and 3 wk, revealed two polydisperse subpopulations (Kav of 0.30 to 0.38 and 0.51 to 0.68). We conclude that this coupled bone-cartilage system is viable for prolonged periods, is suitable for studies on the metabolism of articular cartilage PGs, and seems to have some advantages over the cultured articular cartilage slice system.


Asunto(s)
Huesos/metabolismo , Cartílago Articular/metabolismo , Técnicas de Cultivo/métodos , Proteoglicanos/biosíntesis , Animales , Articulación del Tobillo , Autorradiografía , Huesos/anatomía & histología , Cartílago Articular/anatomía & histología , Bovinos , Estudios de Evaluación como Asunto , Factores de Tiempo
18.
In Vitro Cell Dev Biol Anim ; 30(8): 504-11, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27519865

RESUMEN

Current evidence suggests that interactions between the subchondral bone and the articular cartilage of mammalian diarthrodial joints may occur through the action of bone-associated peptide factors. However, there is no suitable organ culture model for studying these interactions. This study defines a long-term tissue culture system where the articular cartilage is coupled to the adjacent subchondral bone obtained from the proximal ends of bovine metacarpals. Autoradiography done over 3 mo., by utilizing [(35)S]SO4 incorporation into cartilage proteoglycan (PG) and a procedure for cutting non-decalcified bone, demonstrated similar numbers of silver grains over chondrocytes in all cartilage zones, including the bone-cartilage interface. Newly synthesized PG (NSPG) from the cartilage of the "coupled" system over a 3-wk period was primarily of large hydrodynamic size (Kav of 0.34). Comparable bovine articular and nasal cartilage slice systems, incubated for short periods of time, yielded similar and somewhat larger NSPG, respectively. Labeled chondroitin sulphate PG accumulating in the medium of primary chondrocyte monolayer cultures, derived from the cartilage of the coupled system at 0, 1, 2, and 3 wk, revealed two polydisperse subpopulations (Kav of 0.30 to 0.38 and 0.51 to 0.68). We conclude that this coupled bone-cartilage system is viable for prolonged periods, is suitable for studies on the metabolism of articular cartilage PGs, and seems to have some advantages over the cultured articular cartilage slice system.

19.
In Vitro Cell Dev Biol Anim ; 34(6): 492-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9661054

RESUMEN

Primary, high density bovine articular chondrocyte (BAC) cultures, stimulated with transforming growth factor-beta-1, elaborated a high molecular weight anionic glycoconjugate, kDa 540, which does not contain glycosaminoglycan chains (Chan and Anastassiades, 1996). The effect of exogenously added transforming growth factor-beta-1 on the elaboration of the high molecular weight glycoconjugate and of proteoglycans was studied during dedifferentiation of the chondrocytes, utilizing a serial subculture technique under anchorage-dependent conditions, up to four subcultures. The high molecular weight glycoconjugate was detected in the media of all growth-factor-stimulated chondrocyte subcultures, as well as stimulated primary cultures, but not in unstimulated primary cultures or subcultures. By contrast, a large proteoglycan, was only secreted by primary cultures and first subcultures, whether treated with transforming growth factor-beta-1 or untreated. This proteoglycan contained mostly chondroitin sulfate chains, whose hydrodynamic size was increased by the addition of transforming growth factor-beta-1. Further, the pattern of the proteoglycans appearing in the media of subcultures 2-4 was influenced by the addition of transforming growth factor-beta-1, so that while these control subcultures elaborated both the large and small chondroitin sulfate proteoglycans, the equivalent stimulated subcultures elaborated only intermediate sized chondroitin sulfate proteoglycan(s). These results suggest that while dedifferentiation of articular chondrocytes, achieved by subculturing, strongly modulates the effect of exogenously added transforming growth factor-beta-1 on the type of proteoglycan elaborated, the process of dedifferentiation does not influence the transforming-growth-factor-beta-dependent synthesis of the high molecular weight anionic glycoconjugate.


Asunto(s)
Condrocitos/efectos de los fármacos , Glicoconjugados/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Animales , Aniones , Cartílago Articular/citología , Bovinos , Diferenciación Celular , Células Cultivadas , Condrocitos/citología , Condrocitos/metabolismo , Marcaje Isotópico
20.
J Clin Densitom ; 4(4): 363-71, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11748341

RESUMEN

Following a 52-wk randomized controlled trial of intermittent cyclic etidronate therapy in patients using corticosteroids, we performed a 52-wk open-label trial of calcium alone in 114 corticosteroid-treated patients to determine whether the beneficial effect of etidronate is maintained after the drug is discontinued. All patients were given 500 mg/d of elemental calcium. Sixty-one and 53 patients made up the former placebo and etidronate groups, respectively. A total of 89 (98%) of patients in the former placebo and etidronate groups remained on corticosteroids throughout the second year. The mean (SE) percentage change in bone mineral density of the lumbar spine, femoral neck, and trochanter were compared between groups. The difference between groups in mean percentage change from baseline (wk 0, initiation of etidronate or placebo therapy) in the bone density of the lumbar spine, femoral neck, and trochanter, following 104 wk, was 3.8 (0.9), 3.0 (1.1), and 4.3 (1.1), respectively (p < 0.05, all sites), in favor of the former etidronate group. While not significant, the former placebo group demonstrated a slightly larger rate of decline in bone density over the second year than the former etidronate group at all three sites. Following the discontinuation of etidronate therapy, there was no accelerated bone loss and there was evidence of a residual protective effect in both the lumbar spine and femoral neck for up to 1 yr posttreatment.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Ácido Etidrónico/farmacología , Ácido Etidrónico/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Cuello Femoral/fisiopatología , Glucocorticoides/efectos adversos , Cadera/fisiopatología , Humanos , Vértebras Lumbares/fisiopatología , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Osteoporosis/diagnóstico , Osteoporosis/prevención & control , Prednisona/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Fracturas de la Columna Vertebral/inducido químicamente , Fracturas de la Columna Vertebral/prevención & control , Factores de Tiempo
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