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1.
Environ Sci Pollut Res Int ; 30(28): 72607-72616, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37178299

RESUMEN

Exposure to ambient air pollution has been associated with increased rates of mortality and morbidity and a shorter life expectancy. Few studies have evaluated the associations between air pollution and change in calcaneus ultrasound T-score (∆T-score). Therefore, in this longitudinal study, we explored these associations in a large group of Taiwanese participants. We used data from the Taiwan Biobank database and Taiwan Air Quality Monitoring Database, which contains detailed daily data on air pollution. We identified 27,033 participants in the Taiwan Biobank database who had both baseline and follow-up data. The median follow-up period was 4 years. The studied ambient air pollutants included particulates of 2.5 µm or less (PM2.5), particulates of 10 µm or less (PM10), ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), nitric oxide (NO), nitrogen dioxide (NO2), and nitrogen oxide (NOx). Multivariable analysis showed that PM2.5 (ß, -0.003; 95% confidence interval (CI), -0.004 to -0.001; p < 0.001), PM10 (ß, -0.005; 95% CI, -0.006 to -0.004, p < 0.001), O3 (ß, -0.008; 95% CI, -0.011 to -0.004; p < 0.001), and SO2 (ß, -0.036; 95% CI, -0.052 to -0.020; p < 0.001) were negatively associated with ∆T-score, and that CO (ß, 0.344; 95% CI, 0.254, 0.433; p < 0.001), NO (ß, 0.011; 95% CI, 0.008 to 0.015; p < 0.001), NO2 (ß, 0.011; 95% CI, 0.008 to 0.014; p < 0.001), and NOx (ß, 0.007; 95% CI, 0.005 to 0.009; p < 0.001) were positively significantly associated with ∆T-score. Furthermore, PM2.5 and SO2 (ß, -0.014; 95% CI, -0.016 to -0.013; p < 0.001) and PM10 and SO2 (ß, -0.008; 95% CI, -0.009 to -0.007; p < 0.001) had synergistic negative effects on ∆T-score. In conclusion, we found that high PM2.5, PM10, O3, and SO2 were associated with a rapid decline in T-score, whereas high CO, NO, NO2, and NOx were associated with a slow decline in T-score. Furthermore, PM2.5 and SO2 and PM10 and SO2 had synergistic negative effects on ∆T-score, causing an acceleration in T-score decline. These findings may be helpful when developing policies on air pollution regulation.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Calcáneo , Ozono , Humanos , Contaminantes Atmosféricos/análisis , Estudios de Seguimiento , Dióxido de Nitrógeno/análisis , Estudios Longitudinales , Calcáneo/química , Contaminación del Aire/análisis , Dióxido de Azufre/análisis , Ozono/análisis , Óxido Nítrico , Polvo , Material Particulado/análisis , Exposición a Riesgos Ambientales/análisis
2.
Sci Rep ; 8(1): 14603, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30279568

RESUMEN

This study aimed to characterize the relationship between the ratio of the length of the second and fourth fingers (2D:4D value) and the speed of sound of the calcaneus by quantitative ultrasound (QUS-SOS) in undergraduate female students. We recruited 138 young women with a mean age of 19.6 ± 1.4 years. The participants' calcaneus QUS-SOS was measured using an ultrasound bone densitometer. We also measured the participants' weight, height, and grip strength. A self-reported questionnaire was used to obtain information on participants' secondary sexual characteristics, and exercise habits. The present study showed that the 2D:4D value of both hands was significantly correlated with the calcaneus QUS-SOS. The 2D:4D value of the left hand was also positively associated with the calcaneus QUS-SOS results in several respects. These findings suggest that the 2D:4D value may be useful for the screening of risk for a low bone quality in undergraduate female students.


Asunto(s)
Antropometría/métodos , Densidad Ósea/fisiología , Calcáneo/química , Dedos/anatomía & histología , Absorciometría de Fotón/estadística & datos numéricos , Adolescente , Antropometría/instrumentación , Estatura/fisiología , Peso Corporal/fisiología , Calcáneo/anatomía & histología , Calcáneo/diagnóstico por imagen , Calcáneo/fisiología , Femenino , Dedos/diagnóstico por imagen , Dedos/fisiología , Fuerza de la Mano/fisiología , Humanos , Estudiantes , Ultrasonografía/estadística & datos numéricos , Adulto Joven
3.
Biol Res Nurs ; 18(4): 439-44, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26933147

RESUMEN

Identifying modifiable factors that influence bone gain during early adulthood in order to maximize peak bone mass (PBM) is a potential primary strategy in the prevention of osteoporosis in later life. The present study examined the relationships between body composition, dietary intake and physical activity (PA), and bone health measured by quantitative ultrasound (QUS) at the right calcaneus. The study population consisted of 781 Spanish men and women (age 19.1 ± 3.6). Body composition, dietary intake, PA, and bone strength were assessed. Calcaneus QUS was significantly correlated with age, height, weight, body mass index, lean mass, fat mass, protein intake, and moderate and high PA. No significant correlation between calcium intake and broadband ultrasound attenuation (BUA, dB/MHz) was detected. Linear regression analyses revealed that independent variables accounted for 18.8% of the total variance of calcaneus BUA (p = .000). Lean mass and high PA were significant predictors of BUA variance in young adults (p = .000 and p = .045, respectively). Results indicate that lifestyle choices and their consequences during early adulthood could influence bone mass, particularly PA and lean mass. Furthermore, this study provides novel data about bone mass as indicated by the QUS measurements at the time of PBM acquisition.


Asunto(s)
Composición Corporal/fisiología , Peso Corporal/fisiología , Densidad Ósea/fisiología , Calcáneo/química , Calcio/metabolismo , Ejercicio Físico/fisiología , Osteoporosis/diagnóstico , Adulto , Femenino , Humanos , Estilo de Vida , Masculino , Análisis de Regresión , España , Ultrasonografía , Adulto Joven
4.
New Microbiol ; 38(3): 345-56, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26147144

RESUMEN

Human immunodeficiency virus (HIV)-infected patients have an increased risk of developing osteopenia or osteoporosis compared with healthy individuals. Our aim was to compare dual X-ray absorptiometry (DXA), the gold standard for measuring bone mineral density (BMD), with bone quantitative ultrasound (QUS), an alternative technique for predicting fractures and screening low BMD, at least in postmenopausal populations. We analyzed DXA and QUS parameters to investigate their accuracy in the diagnosis and prediction of bone alterations in a cohort of 224 HIV-1-positive patients. The speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness index (SI) parameters showed a moderate correlation with DXA, especially with total-body BMD (r coefficient of 0.38, 0.4 and 0.42 respectively), particularly in the female subgroup. In addition, multivariate analysis of HIV-positive patients assessed for vertebral fractures indicated that QUS was more effective than DXA at predicting the risk of fracture. QUS can be used as an additional tool for analyzing bone density in HIV-positive patients and its case of use and low cost make it especially suitable for resource-limited settings where DXA is not employed.


Asunto(s)
Calcáneo/diagnóstico por imagen , Infecciones por VIH/complicaciones , Osteoporosis/diagnóstico por imagen , Absorciometría de Fotón , Adulto , Anciano , Densidad Ósea , Calcáneo/química , Estudios de Cohortes , Femenino , Infecciones por VIH/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico , Osteoporosis/fisiopatología , Ultrasonografía
5.
Zhongguo Gu Shang ; 26(6): 512-4, 2013 Jun.
Artículo en Chino | MEDLINE | ID: mdl-24015660

RESUMEN

OBJECTIVE: To explore the role of preoperative calcaneal traction in the treatment of Rüedi-Allgöwer II and III Pilon fracture. METHODS: From March 2005 to March 2010, 56 patients with Rüedi-Allgöwer II and III Pilon fracture were treated by calcaneal traction internal fixation on the second phase. There were 42 males and 14 females with an average age of 34.6 years old (ranged 18 to 68). Clinical outcomes were assessed according to Tormette Pilon and tibia fracture standard. RESULTS: All patients were followed up from 9 to 36 months with an average of 18 months. All fracture obtained bone healing, the time ranged from 4.5 to 8.2 months with a mean of 6.2 months. No deep infection, breakage of internal fixation and other complications occurred. According to Tornetta evaluation criteria,35 cases got excellent results, 18 cases good,and 3 cases fair. CONCLUSION: Preoperative calcaneal traction as a temporary fixing measure can provide a good environment for successful operation, and is an essential foundation for recovering functional, painless, load, movable joint.


Asunto(s)
Calcáneo/cirugía , Tibia/química , Fracturas de la Tibia/cirugía , Tracción , Adolescente , Adulto , Anciano , Calcáneo/química , Femenino , Fijación Interna de Fracturas , Humanos , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Tibia/cirugía , Adulto Joven
6.
Tissue Eng Part C Methods ; 19(6): 449-57, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23136872

RESUMEN

Osteochondral defects of the talus pose a difficult therapeutic challenge. An experimental animal model of the ankle joint is not available. The aim of this study was to test a newly developed animal model for osteochondral defects of the ankle in vivo. Osteochondral defects were created in the talus of goat hind legs using a posterolateral surgical approach. The defects were filled with either autologous cancellous bone or donor demineralized bone matrix or left empty as control. After 12 weeks of healing, the specimens were analyzed with radiography, macroscopy, microcomputed tomography, histology, histomorphometry, and fluorescence microscopy. It was possible to create a standardized defect in each talus. The implanted material remained in place. The analyses showed that most bony tissue was generated in the defects filled with autologous bone and least in the control defects. Our findings show that a standard osteochondral defect can be created in the talus by a relatively simple procedure in a large animal that allows qualitative and quantitative evaluation. The model can be used in future experiments to investigate alternative treatment methods before they are introduced into clinical practice.


Asunto(s)
Sustitutos de Huesos , Calcáneo/química , Modelos Animales de Enfermedad , Traumatismos de los Pies/terapia , Cabras , Astrágalo/lesiones , Animales , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Femenino , Traumatismos de los Pies/patología , Astrágalo/patología
7.
J Environ Monit ; 14(12): 3267-75, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23152131

RESUMEN

494 smelter employees from New Brunswick participated in a bone lead survey conducted by McMaster University in 2008, using the four element "clover-leaf" geometry germanium detector system. The employees were measured at two different bone sites, tibia and calcaneus, each measurement lasting 30 minutes. Scattered photons, including Pb X-rays, were collected by the germanium detectors located behind the ¹°9Cd source. A strong positive correlation was observed between tibia and calcaneus lead concentrations. Having been provided with blood lead levels, a cumulative blood lead index (CBLI) was generated. The employees were classified into four groups based on their date of hire, and their CBLI levels were compared to their tibia and calcaneus lead concentrations in the different groups. The slopes of bone Pb versus CBLI varied amongst groups, with those hired earliest showing the steepest slopes. This could be taken to imply a non-linearity in the uptake of Pb by bone from blood. In this paper, the association of the bone lead concentrations versus CBLI has been expressed by a polynomial function for the whole group of employees.


Asunto(s)
Huesos/química , Sustancias Peligrosas/análisis , Plomo/análisis , Exposición Profesional/análisis , Huesos/metabolismo , Calcáneo/química , Calcáneo/metabolismo , Sustancias Peligrosas/sangre , Humanos , Plomo/sangre , Metalurgia , Nuevo Brunswick , Exposición Profesional/estadística & datos numéricos , Tibia/química , Tibia/metabolismo
8.
Clin Chim Acta ; 414: 281-8, 2012 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-23041218

RESUMEN

BACKGROUND: Insulin-like growth factor (IGF) system components are important regulators of bone metabolism, which have a predominant role in determining bone mineral density (BMD). While the serum levels of IGF-I are regulated by various systemic hormones and growth factors, IGF-II levels reflect the skeletal production relative to physical activity, mechanical loading, aging, race etc. Though various studies have been carried out among women of different ethnic groups to understand the relationship between serum levels of IGF-II and BMD, the results seem to be quite inconclusive. METHODS: We evaluated the same, recruiting South-Indian women who engage themselves in a wide variety of physical activities pertaining to their profession and life style. RESULTS: Serum levels of IGF-II and IGF binding protein (IGFBP)-3 showed positive correlation with calcaneal BMD, whereas IGFBP-4 showed negative correlation. These IGF system components exhibited similar correlations with serum bone formation markers and opposite trend with bone resorption marker. While both IGF-II and IGFBP-3 levels were observed to be decreased with aging and menopause, IGFBP-4 levels increased. CONCLUSIONS: The alterations in serum levels of IGF-II and its binding proteins due to aging and menopause could be some of the major contributors of decreased calcaneal BMD observed among elderly women.


Asunto(s)
Envejecimiento/sangre , Densidad Ósea , Calcáneo/química , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor II del Crecimiento Similar a la Insulina/análisis , Posmenopausia/sangre , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , India , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Persona de Mediana Edad , Valores de Referencia , Adulto Joven
9.
Nutr Res ; 31(10): 766-75, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22074801

RESUMEN

Soy milk has become a popular substitute for dairy milk with important health claims. We hypothesized that soy milk, based on its nutrient composition, is comparable to dairy products and, therefore, beneficial for bone health. To test this hypothesis, we examined the benefit of soy milk and dairy products intake on bone health using broadband ultrasound attenuation of the calcaneus. Postmenopausal white women (n = 337) who had completed a lifestyle and dietary questionnaire at enrollment into the Adventist Health Study-2 had their calcaneal broadband ultrasound attenuation measured 2 years later. The association between osteoporosis (defined as a T-score <-1.8) and some dietary factors (soy milk, dairy) and selected lifestyle factors was assessed using logistic regression. In a multivariable model adjusted for demographics, hormone use, and other dietary factors, osteoporosis was positively associated with age (odds ratio [OR] = 1.08; 95% confidence interval [CI], 1.06-1.12) and inversely associated with body mass index (OR = 0.91; 95% CI, 0.86-0.97) and current estrogen use (OR = 0.27; 95% CI, 0.13-0.56). Compared with women who did not drink soy milk, women drinking soy milk once a day or more had 56% lower odds of osteoporosis (OR = 0.44; 95% CI, 0.20-0.98; P(trend) = .04). Women whose dairy intake was once a day or more had a 62% reduction in the likelihood of having osteoporosis (OR = 0.38; 95% CI, 0.17-0.86; P(trend) = .02) compared with women whose dairy intake was less than twice a week. Among individual dairy products, only cheese showed an independent and significant protection (OR = 0.28; 95% CI, 0.12-0.66; P(trend) = .004) for women eating cheese more than once per week vs those who ate cheese less than once a week. We concluded that osteoporosis is inversely associated with soy milk intake to a similar degree as dairy intake after accounting for age, body mass index, and estrogen use.


Asunto(s)
Calcáneo/diagnóstico por imagen , Productos Lácteos , Osteoporosis Posmenopáusica/etiología , Osteoporosis Posmenopáusica/prevención & control , Posmenopausia , Leche de Soja/administración & dosificación , Anciano , Índice de Masa Corporal , Calcáneo/química , Canadá/epidemiología , Estudios de Cohortes , Estudios Transversales , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Humanos , Estilo de Vida , Persona de Mediana Edad , Osteoporosis Posmenopáusica/diagnóstico por imagen , Prevalencia , Riesgo , Estadística como Asunto , Encuestas y Cuestionarios , Ultrasonografía , Estados Unidos/epidemiología
10.
J Bone Miner Metab ; 28(1): 94-100, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19634016

RESUMEN

This study evaluated age-related changes in bone mineral density (BMD) and identified the peak bone mineral density (PBMD) in Koreans. We recruited 2929 subjects, ranging in age from 5 to 86 years, from three regions: Seoul, Siwha, and Gwangyang. The BMD at the distal radius and calcaneus were measured with dual-energy X-ray absorptiometry, and anthropometric measures were also obtained. PBMD was calculated from the highest mean in each age group. The PBMD at the distal radius was 0.514 +/- 0.06 g/cm(2) in females and 0.598 +/- 0.07 g/cm(2) in males. Peak ages for both sexes were the thirties. For the calcaneus, PBMD was 0.509 +/- 0.09 g/cm(2) in females and 0.629 +/- 0.09 g/cm(2) in males. Peak ages were the thirties for females and the twenties for males. These results could facilitate international or interracial comparisons and be used as reference data to screen for osteoporosis in Koreans.


Asunto(s)
Envejecimiento/fisiología , Densidad Ósea , Calcáneo/química , Osteoporosis/diagnóstico por imagen , Radio (Anatomía)/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antropometría , Índice de Masa Corporal , Resorción Ósea , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Valores de Referencia , República de Corea , Caracteres Sexuales , Adulto Joven
11.
Connect Tissue Res ; 50(5): 279-84, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19863386

RESUMEN

The role of physical activity in affecting the composition of extracellular matrix and mechanical properties of tendons has been well studied, but little is known about the role of passive stretching. The purpose of this study was to test the hypothesis that stimulation by passive stretching may change the composition and mechanical properties of tendons. Three-month-old Wistar rats were divided into three groups: the control, animals were not submitted to stretching procedures; groups that had their calcaneal tendons manually stretched three or five times a week, for 21 days. Afterward, the calcaneal tendons were removed and assayed for hydroxyproline content and biomechanical test. The hydroxyproline content in the stretched groups was higher, suggesting that more collagen was present in the tendons of these groups. These tendons also showed higher values of maximum stress and modulus of elasticity or Young's modulus. These results indicate that stretching leads to alterations in the synthesis of the extracellular matrix components and in the mechanical properties of tendons.


Asunto(s)
Calcáneo/química , Calcáneo/fisiología , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Tendones/química , Tendones/fisiología , Resistencia a la Tracción/fisiología , Adaptación Fisiológica/fisiología , Animales , Fenómenos Biomecánicos , Calcáneo/anatomía & histología , Elasticidad/fisiología , Fibroblastos/metabolismo , Hidroxiprolina/análisis , Hidroxiprolina/metabolismo , Locomoción/fisiología , Masculino , Movimiento/fisiología , Contracción Muscular/fisiología , Ratas , Estrés Mecánico , Tendones/anatomía & histología , Regulación hacia Arriba/fisiología
12.
J Steroid Biochem Mol Biol ; 117(4-5): 132-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19732831

RESUMEN

Male osteoporosis is an increasingly important health problem worldwide. Though androgen deficiency leads to bone loss in men, information on the relative contribution of aromatizable and non-aromatizable androgens in maintaining bone mineral density (BMD) and the mechanisms involved are unclear. This cross-sectional study was designed to explore the same. Hundred osteoporotic men with age matched normal were studied for serum levels of sex steroids, PTH, IGF system components, cytokines and bone turnover markers. Our findings show that serum DHT, IGF-I, IGF-II and IGFBP-3 levels were significantly decreased while IL-1beta and bone turnover markers were significantly increased in osteoporotic men compared to normal. Pearson correlation analysis revealed that serum DHT, IGF-I, IGF-II and IGFBP-3 levels were positively and strongly correlated with BMD, while serum IL-1beta levels were negatively correlated with BMD. Serum PTH, testosterone, estradiol, IGFBP-4, TNF-alpha, IL-4 and IFN-gamma levels were similar between the two groups. We observed that DHT levels significantly declined with age. However, the significant difference in DHT between the osteoporotic and normal groups is the same regardless of age. A multiple regression model adjusted for age demonstrated that DHT/BMD association is fairly stronger among those with osteoporosis than the normal. Our findings for the first time point out that DHT is an important determinant of BMD in men. Most importantly, the strong positive correlation of serum DHT with BMD offers new perspectives in understanding the role of non-aromatizable androgen in regulating bone metabolism in men, and might serve as a potential clinical marker in the diagnosis of male osteoporosis.


Asunto(s)
Densidad Ósea , Calcáneo/química , Dihidrotestosterona/sangre , Absorciometría de Fotón , Adulto , Anciano , Índice de Masa Corporal , Estudios de Casos y Controles , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/sangre
13.
Tohoku J Exp Med ; 219(1): 63-9, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19713686

RESUMEN

The assessment of growth, including the developmental change in bone mass, is crucial for child health care. We herein report normative values of bone mineral density (BMD) for calcaneus obtained from a large cross-section sample in Japanese school children. To investigate yearly physical growth from pre-school age to adulthood, we measured height, weight, body mass index (BMI), and BMD in 3,835 school children aged 3 to 18 (1,886 boys and 1,949 girls). Participating institutions included kindergarten, junior high schools, high schools, and a college of technology. The growth pattern (or velocity) of BMD (the ratio of trabecular bone area of the calcaneum) shows 3 phases according to the age rage: 3-10, 11-15, and 16-18 years for boys, and 3-7, 8-15, and 16-18 years for girls, both peaking at age 16 years. Likewise, that of weight shows 3 phases: 3-4, 5-15 and 16-18 years for boys, and 3-4, 5-14 and 15-18 years for girls, while the growth pattern of height shows 2 phases: 3-15 and 16-18 years for boys, and 3-13 and 14-18 years for girls, both sexes peaking at approximately 16 years. Therefore, the physical growth pattern of the school children shows progressive growth until 16 years, at which time growth is generally completed. In children under 16 years old, BMD of the calcaneus is higher in girls than in boys. Boys and girls show a similar growth pattern in body height and weight before peak development; however, the physical growth of boys eventually exceeds that of girls.


Asunto(s)
Densidad Ósea/fisiología , Calcáneo/química , Densitometría , Crecimiento y Desarrollo/fisiología , Ultrasonografía , Adolescente , Envejecimiento/fisiología , Estatura/fisiología , Índice de Masa Corporal , Peso Corporal/fisiología , Calcáneo/diagnóstico por imagen , Calcáneo/crecimiento & desarrollo , Niño , Preescolar , Femenino , Humanos , Japón , Masculino , Obesidad/diagnóstico , Caracteres Sexuales
14.
Anat Rec (Hoboken) ; 290(3): 284-300, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17525944

RESUMEN

Experimental models are needed for resolving relative influences of genetic, epigenetic, and nonheritable functionally induced (extragenetic) factors in the emergence of developmental adaptations in limb bones of larger mammals. We examined regional/ontogenetic morphologic variations in sheep calcanei, which exhibit marked heterogeneity in structural and material organization by skeletal maturity. Cross-sections and lateral radiographs of an ontogenetic series of domesticated sheep calcanei (fetal to adult) were examined for variations in biomechanically important structural (cortical thickness and trabecular architecture) and material (percent ash and predominant collagen fiber orientation) characteristics. Results showed delayed development of variations in cortical thickness and collagen fiber orientation, which correlate with extragenetic factors, including compression/tension strains of habitual bending in respective dorsal/plantar cortices and load-related thresholds for modeling/remodeling activities. In contrast, the appearance of trabecular arches in utero suggests strong genetic/epigenetic influences. These stark spatial/temporal variations in sheep calcanei provide a compelling model for investigating causal mechanisms that mediate this construction. In view of these findings, it is also suggested that the conventional distinction between genetic and epigenetic factors in limb bone development be expanded into three categories: genetic, epigenetic, and extragenetic factors.


Asunto(s)
Adaptación Fisiológica , Envejecimiento , Desarrollo Óseo , Calcáneo/anatomía & histología , Ovinos/anatomía & histología , Adaptación Fisiológica/genética , Envejecimiento/fisiología , Anatomía Transversal , Animales , Fenómenos Biomecánicos , Densidad Ósea , Desarrollo Óseo/genética , Calcáneo/química , Calcáneo/diagnóstico por imagen , Calcáneo/embriología , Colágeno/análisis , Ciervos/anatomía & histología , Ciervos/crecimiento & desarrollo , Modelos Biológicos , Radiografía , Ovinos/embriología , Ovinos/crecimiento & desarrollo , Estrés Mecánico , Factores de Tiempo
15.
Arthroscopy ; 22(3): 265-9, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16517309

RESUMEN

PURPOSE: To monitor changes in bone mineral density (BMD) of the proximal tibia and the calcaneus in patients with anterior cruciate ligament (ACL) rupture before and after arthroscopic reconstruction of the ligament, related to clinical data. TYPE OF STUDY: A 2-year prospective cohort study with assessment of patient evaluation of knee performance, clinical scoring of surgical results, and measurement of BMD in the tibia and calcaneus. METHODS: Eighteen patients with a unilateral ACL rupture underwent an autogenous bone-patellar tendon-bone graft ACL reconstruction. The patients were examined before surgery and after 4, 12, and 24 months. BMD was assessed bilaterally in the proximal tibia and calcaneus using dual-photon absorptiometry and converted to a Z-score by use of BMD values from a group of healthy controls. Clinical evaluation included determination of Lysholm score, quantitative Lachman test, pivot-shift test, and the patients' self-reported highest level of activity and knee performance in sports and daily activities. RESULTS: There were significant declines in Z-score of the proximal tibia of the operated leg during the first year after surgery, whereas there was no change in the calcaneus and contralateral leg. In the lateral tibia, the Z-score was significantly lower at 24 months follow-up, compared with both controls and the noninjured side, whereas BMD of the medial tibia had returned to near normal levels. There were significant improvements in Lysholm score, highest level of activity, and knee performance in daily activities and sports. The patients' evaluation of improvement in knee performance in sports activities at 24 months follow-up was associated with an increase in Z-score of the injured leg. CONCLUSIONS: We found a partially reversible decline in BMD of the proximal tibia after arthroscopic ACL reconstruction. Improvement in knee performance in sports activities was associated with an increase in BMD of the injured leg. BMD of the calcaneus remained unaffected in both legs. LEVEL OF EVIDENCE: Level III, therapeutic case control study.


Asunto(s)
Ligamento Cruzado Anterior/cirugía , Artroscopía , Densidad Ósea , Calcáneo/química , Tibia/química , Actividades Cotidianas , Adulto , Lesiones del Ligamento Cruzado Anterior , Enfermedades Óseas Metabólicas/epidemiología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Fémur/cirugía , Fémur/trasplante , Humanos , Masculino , Minerales/análisis , Ligamento Rotuliano/trasplante , Satisfacción del Paciente , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Recuperación de la Función , Rotura/cirugía , Índice de Severidad de la Enfermedad , Deportes , Tibia/cirugía , Tibia/trasplante , Trasplante Autólogo , Resultado del Tratamiento
16.
Am J Ind Med ; 49(3): 143-52, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16470548

RESUMEN

OBJECTIVE: The Bunker Hill mine in Idaho operated from 1886 to 1981. In the 60's and 70's it provided approximately 25% of the primary lead in the United States. Women first began working on the production and maintenance lines in 1972. This study examines the impact of menopause and several occupational and lifestyle factors as determinants of blood and bone lead levels among 73 female former smelter workers. METHODS: Blood lead levels were analyzed using graphite furnace atomic absorption spectroscopy. The (109)Cd K X-ray fluorescence system was used to measure calcaneus and tibia bone lead content. Information was obtained on reproductive history, alcohol and cigarette consumption, education, and hormone replacement therapy (HRT). RESULTS: Postmenopausal women (n = 47) had significantly (P < 0.002) higher blood lead levels (3.48 microg/dl) than did premenopausal women (n = 26) (2.19 microg/dl). The best predictors of blood lead levels were smoking (>10 or < or =10 cigarettes/day), natural menopause, technical or community college education, manager or technical worker, and past or present use of HRT. The best predictors of calcaneus bone lead levels (P < 0.2) were technical workers, such as miner; natural menopause; and smoking >10 cigarettes/day; level of education; 1-2 pregnancies; and age (>60 years). CONCLUSIONS: Lead exposure results in higher blood lead levels especially during menopause.


Asunto(s)
Calcáneo/química , Plomo/análisis , Estilo de Vida , Menopausia/sangre , Minería , Tibia/química , Adulto , Factores de Edad , Escolaridad , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Ocupaciones , Fumar/sangre
17.
J Environ Monit ; 7(3): 241-7, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15735782

RESUMEN

This paper describes a new metabolic model for lead in humans and a numerical method to solve the differential equations governing the transfer of lead between body compartments. The model includes 3 compartments-cortical bone, trabecular bone and blood-and accounts for absorption from external sources and release through excreta. Estimation of the lead kinetics parameters was performed using the grid search method. Grid search is a simple procedure that allows the fit of an arbitrary function to data. When applied to data from occupationally exposed populations, the method demonstrated the exposure dependence of the rate of lead uptake and release by the compartments in the model. The results confirm and refine previous observations of the significant decrease of the transfer rate of lead from cortical bone to blood with increasing exposure, as expressed by half-lives of (in years): 6.5 +/- 0.7, 13.6 +/- 1.0 and 47.5 +/- 2.3, in subgroups of low, intermediate and high long-term lead exposure. A similar trend was observed for the transfer rate from trabecular bone, which could be statistically supported for the first time. Reduction by a factor of 7 to 10 in the default values assigned to the fractional removal of lead from cortical bone to plasma in existing metabolic models was also predicted. These results can be used in the review of current metabolic models for lead, which are still based on the assumption of a constant rate of lead removal from bone, independently of the level of exposure.


Asunto(s)
Calcáneo/metabolismo , Plomo/metabolismo , Metalurgia , Modelos Biológicos , Exposición Profesional , Tibia/metabolismo , Adulto , Anciano , Calcáneo/química , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Humanos , Plomo/análisis , Plomo/sangre , Masculino , Persona de Mediana Edad , Espectrometría por Rayos X , Tibia/química
18.
J Bone Miner Res ; 19(8): 1215-20, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15231007

RESUMEN

UNLABELLED: The relationship of low bone mass and fracture in younger postmenopausal women has not been extensively studied. In a large cohort of postmenopausal women > or =50 years of age, we found the relationship of BMD measured at peripheral sites and subsequent 1-year fracture risk to be similar between women <65 and those > or =65 years of age. INTRODUCTION: Low bone mass and fractures are prevalent in older postmenopausal women. However, the frequency of low bone mass and fracture in younger postmenopausal women has not been studied extensively. There are very limited data regarding the association between BMD measurements and fractures in postmenopausal women who are between the ages of 50 and 64. MATERIALS AND METHODS: In the National Osteoporosis Risk Assessment (NORA) we studied the frequency of low bone mass and its association with fracture in women 50-64 years of age in comparison with women > or =65 of age. NORA enrolled 200,160 postmenopausal women > or =50 years of age who had no prior diagnosis of osteoporosis. Baseline BMD was measured at the heel, forearm, or finger. A 1-year follow-up survey requesting incident fractures since baseline was completed by 163,935 women, 87,594 (53%) of whom were 50-64 years of age. The association between BMD and fracture was assessed using logistic regression, adjusted for important covariates. RESULTS: Thirty-one percent of women 50-64 years of age had low bone mass (T scores < or = -1.0) compared to 62% of women > or =65 years of age. During the first year of follow-up, 2440 women reported fractures of wrist/forearm, rib, spine, or hip, including 440 hip fractures. Nine hundred four women 50-64 years of age reported fractures, including 86 hip fractures, accounting for 37% of fractures and 20% of hip fractures reported in the entire NORA cohort. Relative risk for osteoporotic fracture was 1.5 for each SD decrease in BMD for both the younger and older groups of women. CONCLUSION: Low BMD in younger postmenopausal women 50-64 years of age showed a 1-year relative risk of fracture similar to that found in women > or =65 years of age.


Asunto(s)
Densidad Ósea , Fracturas Óseas/epidemiología , Posmenopausia , Factores de Edad , Anciano , Anciano de 80 o más Años , Huesos de la Extremidad Superior/química , Calcáneo/química , Femenino , Traumatismos del Antebrazo/epidemiología , Fracturas Óseas/etnología , Fracturas de Cadera/epidemiología , Humanos , Anamnesis , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Fracturas de las Costillas/epidemiología , Medición de Riesgo , Fracturas de la Columna Vertebral/epidemiología , Encuestas y Cuestionarios , Estados Unidos/epidemiología
19.
J Biomed Opt ; 9(3): 474-80, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15189084

RESUMEN

In vivo absorption and reduced scattering spectra of the human calcaneous from 650 to 1000 nm were assessed using a laboratory system for time-resolved transmittance spectroscopy. Measurements were performed on the calcaneous of seven female volunteers ranging from 26 to 82 years of age. The analysis of the absorption spectra, using a linear combination of the key tissue absorbers (bone mineral, water, lipids, oxy- and deoxyhemoglobin), revealed a general decrease in bone mineral content and an increase in lipids with age, which is in agreement with the aging transformations that occur in bone tissues. The scattering spectra were less effective in detecting such changes in older subjects, showing only a minor decrease in the coefficient for these subjects. The capability to noninvasively quantify bone tissue composition suggests a possible use of optical biopsy for the diagnosis of bone pathologies such as osteoporosis, which are characterized by a progressive reduction and transformation of the mineral in the bone matrix.


Asunto(s)
Calcáneo/química , Calcáneo/patología , Interpretación de Imagen Asistida por Computador/métodos , Análisis Espectral/métodos , Tomografía Óptica/métodos , Adulto , Anciano , Envejecimiento/fisiología , Biopsia/métodos , Enfermedades Óseas/diagnóstico , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad
20.
Neurology ; 62(11): 2051-7, 2004 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-15184613

RESUMEN

OBJECTIVE: To test the hypothesis that older women with antiepileptic drug (AED) use have increased rates of bone loss. METHODS: AED use was ascertained and calcaneal and hip bone mineral density (BMD) measured in a cohort of 9,704 elderly community-dwelling women enrolled in the Study of Osteoporotic Fractures, and they were followed prospectively for changes in BMD. Current use of AED was assessed by interview, with verification of use from medication containers at baseline and follow-up examinations. Women were classified as continuous users, partial (intermittent) users, or nonusers. Rates of change in BMD were measured at the total hip and two subregions (average 4.4 years between examinations) and at the calcaneus (average 5.7 years between examinations). RESULTS: After adjustment for confounders, the average rate of decline in total hip BMD steadily increased from -0.70%/year in nonusers to -0.87%/year in partial AED users to -1.16%/year in continuous AED users (p value for trend = 0.015). Higher rates of bone loss were also observed among continuous AED users at subregions of the hip and at the calcaneus. In particular, continuous phenytoin users had an adjusted 1.8-fold greater mean rate of loss at the calcaneus compared with nonusers of AED (-2.68 vs -1.46%/year; p < 0.001) and an adjusted 1.7-fold greater mean rate of loss at the total hip compared with nonusers of AED (-1.16 vs -0.70%/year; p = 0.069). CONCLUSIONS: Continuous AED use in elderly women is associated with increased rates of bone loss at the calcaneus and hip. If unabated, the rate of hip bone loss among continuous AED users is sufficient to increase the risk of hip fracture by 29% over 5 years among women age 65 years and older.


Asunto(s)
Anticonvulsivantes/efectos adversos , Enfermedades Óseas Metabólicas/inducido químicamente , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/uso terapéutico , Densidad Ósea , Calcáneo/química , Calcio/uso terapéutico , Estudios de Cohortes , Terapia de Reemplazo de Estrógeno/estadística & datos numéricos , Femenino , Fémur/química , Fracturas Espontáneas/epidemiología , Fracturas Espontáneas/etiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Humanos , Osteoporosis/complicaciones , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Fenitoína/efectos adversos , Estudios Prospectivos , Factores de Riesgo , Estados Unidos/epidemiología , Vitaminas/uso terapéutico
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