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91.
Evaluation of the possibility to assess bone age on the basis of DXA derived hand scans—preliminary results 总被引:2,自引:0,他引:2
Pawe??P?udowski Micha??Lebiedowski Roman?S.?LorencEmail author 《Osteoporosis international》2004,15(4):317-322
The classical method of skeletal age assessment is based on the recognition of changes in the radiographic appearance of the maturity indicators in hand-wrist radiographs by comparison with a reference atlas. The purpose of this study was the evaluation of the possibility to assess bone age using a less invasive method such as dual-energy X-ray absorptiometry (DXA). Bone ages of 50 children free of any chronic diseases (5–18 years old) and ten with multihormonal pituitary deficiency (MPD) (8–20 years old) were assessed using an Expert-XL densitometer. Hand scans and classical hand-wrist radiographs were evaluated by two independent observers for bone age by visual comparison with reference standards of skeletal development published in the atlas. The precision errors of duplicate bone age ratings were low both for radiographs (<1%) and DXA hand scans (<0.9%). A high degree of agreement between bone age ratings done by two observers was assessed by intraclass correlation coefficients. The same bone age based on radiographs and DXA hand scans was assessed in 44 of 60 cases (73.3%); in 16 cases the differences between bone age were no higher than 0.5 year. No significant difference between mean bone age based on radiographs and DXA hand scans was observed (P>0.05). Moreover, there was a very strong correlation between bone age results (r=0.998; r
2=0.996; P<0.0001), indicating agreement of bone age assessments based on DXA and radiographic images. Remarkable differences (up to 3 years) between bone age and chronological age were observed in healthy subjects, probably reflecting the effect of the secular trend towards earlier maturation or alterations in pubertal development. The study indicates that evaluation of skeletal maturity using DXA images is less invasive (up to 8 µSv) than radiography, giving results comparable to the classical method. 相似文献
92.
Dubois EF Wagemans MF Verdouw BC Zwinderman AH Van Boxtel CJ Dekhuijzen PN Schweitzer DH 《Clinical rheumatology》2003,22(1):12-17
The medical use of glucocorticoids (GCs) is related to low bone mineral density (BMD). In this study we tested the hypothesis
that the cumulative dose of GC is not related to BMD outcome. The study was cross-sectional in design and included healthy
individuals with chronic low back pain resistant to conventional treatments. In two steroid-naive subjects cortisol and methylprednisolone
(MP) concentrations were serially assessed after a single MP depot injection (160 mg epidurally). Furthermore, in 14 men and
14 postmenopausal women, previously treated with multiple epidural MP depots, endocrine parameters were analysed in relation
to BMD outcomes. The minimal cumulative MP dose received by all 28 subjects was 3 g. In the two steroid-naive subjects, cortisol
concentrations were completely suppressed for at least 6 days and partly recovered over the course of 30 days. During this
period, MP concentrations remained detectable in plasma. In the 28 subjects, the cumulative MP dose received was 7.76±4.23
g in the men and 8.50±3.13 g in the women (mean±1SD). None of the men had osteoporosis, but osteopenia was prevalent in 78.5%
according to WHO criteria extrapolated to men. Half of the women had osteoporosis and half of them had osteopenia. The body
mass index (BMI) and endogenous oestradiol levels of the men were not related to BMD outcomes. Univariate linear relationships
in women were found between BMI and spinal (r 0.62; P=0.02) and total hip BMD (r 0.61; P=0.03), but not femoral neck BMD. In women, relationships were also found between the total and, for protein binding-corrected
oestradiol levels, and spinal BMD (r 0.70; P=0.01 and r 0.72; P=0.01, respectively) and total hip BMD (r 0.53; P=0.08 and r 0.56; P=0.05, respectively). No significance was observed between endogenous oestradiol levels and the BMD of the femoral neck. The
administration of a single MP depot injection (160 mg) resembled a systemic low peak dose GC exposure. The administration
of multiple MP depots in men and women with chronic low back pain revealed no relationship between cumulative GC dose and
BMD. These findings support the hypothesis of a non-existent relationship between cumulative GC dose and BMD outcomes in healthy
men and women with a prior GC administration of at least 3 g.
Received: 18 February 2002 / Accepted: 14 June 2002
Acknowledgements We are indebted to Dr Oscar L.H. van Hemel for advice during the performance of the study and to Ineke Bosman for excellent
laboratory support. 相似文献
93.
Kok DJ Uiterwaal CS Van Dongen AJ Kramer PP Pruijs HE Engelbert RH Verbout AJ Schweitzer DH Sakkers RJ 《Calcified tissue international》2003,73(5):441-445
Clinical studies with bisphosphonates in children with osteogenesis imperfecta (OI) show an increase in BMD and a decrease in fracture rate. Bone strength in children with OI is not only influenced by changes in BMD but also by changes in collagen I structure of the organic bone matrix. Therefore, we studied the interaction between these two factors in a cross-sectional, single center study including 54 children. We assumed that vertebral deformities in OI represent an unbalance between load and bone strength. Body weight was considered to be a well quantifiable load on vertebral bodies. BMD served as a marker, representing the amount of bone tissue available for vertebral load bearing, and the Sillence classification, either type I or III/IV, as a marker representing the quality of the organic bone matrix. Independent associations were observed between the prevalence of vertebral deformities and (1) Sillence type (OR: 5.7, 95%Cl:1.2–26.8), (2) BMD (OR: 0.003, 95%Cl: 0–0.25) and (3) body weight (OR: 1.15, 95%Cl: 1.05–1.25). Regarding the anthropometrical differences among the different types of OI, the BMD/body weight ratio was introduced to evaluate the BMD in relation to body size. Prevalent vertebral deformities were associated with low BMD/body weight ratios (OR: 0.04, 95%Cl: 0.008–0.2) in OI type I, but no association was found in type III/IV. It was concluded that BMD and Sillence type have independent relationships with vertebral deformities. The BMD/body weight ratio correlates with vertebral deformities in children with OI type I. Its meaning in types III/IV needs further research with larger samples because of the relatively high prevalence of vertebral deformities in this group. 相似文献
94.
Estrogen receptor alpha (ER) and collagen IA1 (COLIA1) genes have been suggested as possibly implicated in reduced bone mineral density (BMD). The present study investigated the occurrence of association and linkage disequilibrium between radiographic hand BMD and polymorphic alleles of ER and COLIA1 genes, in human pedigrees of a Chuvasha population in Russia. The study sample included 463 members of 113 pedigrees, mostly nuclear families. We performed association and transmission disequilibrium test (TDT) analyses of the combined PvuII and XbaI RFLPs alleles on the same chromosome (haplotype) of the ER gene with BMD Z scores of cancellous or cortical bone in the hand phalanges. The association analyses were performed separately for both genders in the parental generation, i.e., fathers (n = 114; average age 64.2 y) and mothers (n = 122; average age 62.7 y). The Px haplotype was associated significantly with lower BMD Z scores in mothers only. The difference between subjects who carried one or two copies of the Px haplotype and those lacking it was 0.68 Z scores, P = 0.003 and 0.51 Z scores, P = 0.025 for cancellous and cortical bone, respectively. Multiple linear regression model with age, height, weight, and Px haplotype status as predictors explained 26.7% and 28.3% of the total observed variance in BMD with Px haplotype as independent predictor explaining 5.9%; P = 0.002 and 3%; P = 0.028 (cancellous and cortical bone, respectively). Results of t-TDT for triads of two parents and just one of their female offspring (but not male offspring) suggested the existence of linkage disequilibrium between the two loci of Px haplotype and BMD trait (P = 0.047). No association was found between polymorphic alleles of COLIA1 gene and BMD, but mothers with combined genotypes of Px haplotype of ER gene and s allele of COLIA1 gene had the lowest mean Z scores (–0.944 and –0.788 for cancellous and cortical bone, respectively). We conclude that the Px haplotype of the ER gene is associated with low BMD values in females, as the phenotype is gender dependent (the association was not observed in males), and the s allele of COLIA1 gene in combination with this haplotype contributes to reduced BMD. 相似文献
95.
Polymorphisms of four bone mineral density candidate genes in Chinese populations and comparison with other populations of different ethnicity 总被引:13,自引:0,他引:13
Lei SF Deng FY Liu XH Huang QR Qin Y Zhou Q Jiang DK Li YM Mo XY Liu MY Chen XD Wu XS Shen H Dvornyk V Zhao L Recker RR Deng HW 《Journal of bone and mineral metabolism》2003,21(1):34-42
Studies on polymorphisms of candidate genes and their association with bone mineral density (BMD) have been reported in many
populations, but few have been reported in Chinese populations. We investigated polymorphisms of the following five commonly
used markers of four prominent BMD candidate genes with the purpose of identifying useful genetic markers for osteoporosis
genetic research in Chinese: the Sp1 and RsaI polymorphisms of the collagen type 1 alpha l (Col1a1) gene, the −174G/C promoter
polymorphism of the interleukin 6 (IL-6) gene, the Asn363Ser polymorphism of the glucocorticoid receptor (GR) gene, and the
T → C polymorphism in intron 5 of the transforming growth factor β1 (TGF-β1) gene. We evaluated these polymorphisms using PCR-RFLP in samples of at least 124 random individuals. We compared the polymorphisms
of these five markers with other populations using the χ2 test and Fisher's exact two-tailed test. For the RsaI polymorphism, only three heterozygotes but no variant homozygote were
identified. For the −174G/C polymorphic site, only one GC heterozygote and no CC homozygote were found. Alleles s, Ser, and A
1
at the Sp1, Asn363Ser, and T → C marker sites that have been found to be polymorphic in other populations were not found
in Chinese. Significant differences of allele and genotype frequency distributions were observed at these polymorphisms (P < 0.001) after comparing with other populations. Our results suggest that variant alleles of the five markers are absent
or too rare to be useful genetic makers in Chinese, despite the fact that they have been commonly used as polymorphic markers
in osteoporosis genetic research in other populations.
Received: April 22, 2002 / Accepted: July 2, 2002
Acknowledgments. The study was partially supported by the Hunan Province Special Professor Start-up Fund (25000612), Chinese National Science
Foundation (CNSF) Outstanding Young Scientist Award (30025025), CNSF Grant (30170504), a grant from Huo Ying-Dong Education
Foundation, and a Seed Fund from the Ministry of Education of P.R. China (25000106). Some investigators (R.R.R., V.D., H.W.D.)
were partially supported by grants from the Health Future Foundation of USA, grants of National Health Institute (K01 AR02170-01,
R01 GM60402-01A1), grants from the State of Nebraska Cancer and Smoking Related Disease Research Program, and U.S. Department
of Energy grant (DE-FG03-00ER63000/A00). We thank all the study subjects for volunteering to participate in the study.
Offprint requests to: H.-W. Deng 相似文献
96.
Therbo M Petersen MM Nielsen PK Lund B 《Scandinavian journal of medicine & science in sports》2003,13(3):194-199
In a prospective uncontrolled study 12 patients suffering from a rupture of the Achilles tendon treated operatively with surgical repair and post-operative immobilization in a short plaster cast for 6 weeks had bilateral measurements of bone mineral content (BMC) of the proximal tibia and bone mineral density (BMD) of the femoral neck and greater trochanter. The measurements were performed by dual energy X-ray absorptiometry (DEXA) and scans were performed post-operatively within 7 days after the operation and with follow up after 6 weeks, 3, 6, and 12 months. In the operated legs, BMC of the proximal tibia showed a progressive decrease reaching a total bone loss of 6.4% (95%-CL: -10.6%; -2.3%) 1 year after the injury. Bone mineral density at the hip of the operated legs also decreased significantly and 1 year after the injury BMD was 2.5% (95%-CL: -5.5%; 0.5%) and 6.8% (95%-CL: -9.8%; -3.7%) below the initial value in, respectively, the femoral neck and greater trochanter. Patients with a previous Achilles tendon rupture must be considered to be some years ahead in their natural osteoporotic process of the bones of the affected legs, and an increased risk of osteoporotic fractures must be considered not to be only theoretical. 相似文献
97.
目的 观察血脂正常但骨密度降低的绝经妇女补充钙、维生素D和大豆异黄酮后,机体骨密度和血脂成分的变化。方法 2004年4月从武汉郊区绝经妇女中筛选血脂正常伴骨量减少或骨质疏松的绝经妇女60名,随机均分为两干预组,每组30人。一组给予液体钙(含维生素D);一组给予液体钙(含维生素D)和大豆异黄酮,跟踪观察一年。测定每位受试对象骨骼骨密度和血脂成分。结果 试验结束后,补钙组和补钙+大豆异黄酮组,全身及股骨颈的骨密度(BMD)都较基线时显著降低(P〈0.05),组间变化无显著性差异(P〉0.05);而腰椎、大转子BMD与基线相比,略微升高,但尚无统计学差异。补钙和补钙+大豆异黄酮均能显著降低血总胆固醇(P〈0.05)。结论 对已出现骨量减少的绝经后妇女补钙一年能降低绝经后BMD的丢失速率,但补充大豆异黄酮一年尚未观察到对BMD的保护作用。绝经妇女补充钙和大豆异黄酮补可能干扰机体的血脂代谢。 相似文献
98.
尼尔雌醇和利维爱对绝经后妇女骨密度的影响 总被引:4,自引:0,他引:4
目的 对104例绝经后妇女应用尼尔雌醇与利维爱后骨密度的变化进行比较性的分析。方法 将年龄47 ̄58岁已绝经2 ̄10年妇女随机分为两组:A组67例口服尼尔雌醇2.5mg,每2周1次,用3个月后在最后1个月加用安宫黄体酮10mg,每天1次,共10 ̄14天。B组口服利维爱1.25mg,每天1次。两组均于用药前,服药后3个月,6个月、12个月用美国LUNAR公司生产的Achilles+跟骨定量超声分析仪 相似文献
99.
Summary The association between a newly identified CA repeat polymorphism of the estrogen receptor alpha gene (ESR1) with osteoporosis
was investigated. Postmenopausal women with <18 CA repeats had low BMD, increased rate of bone loss and increased fracture
risk.
Introduction Studies have shown that intronic dinucleotide repeat polymorphisms in some genes are associated with disease risk by modulating
mRNA splicing efficiency. D6S440 is a newly identified intronic CA repeat polymorphism located downstream of the 5’-splicing
site of exon 5 of ESR1.
Methods The associations of D6S440 with bone mineral density (BMD), rate of bone loss and fracture risk were evaluated in 452 pre-,
110 peri- and 622 postmenopausal southern Chinese women using regression models.
Results Post- but not premenopausal women with less CA repeats had lower spine and hip BMD. The number of CA repeats was linearly
related to hip BMD in postmenopausal women (β = 0.008; p = 0.004). Postmenopausal women with CA repeats <18 had higher risks of having osteoporosis (BMD T-score<−2.5 at the spine:
OR 2.46, 95% CI 1.30–4.65; at the hip: OR 3.79(1.64–8.74)) and low trauma fractures (OR 2.31(1.29–4.14)) than those with ≥18
repeats. Perimenopausal women with <18 CA repeats had significantly greater bone loss in 18 months at the hip than those with
≥18 repeats (−1.96% vs. −1.61%, p = 0.029).
Conclusions ESR1 CA repeat polymorphism is associated with BMD variation, rate of bone loss and fracture risk, and this may be a useful
genetic marker for fracture risk assessment.
Funding Source: This project is supported by CRCG Grant, Bone Health Fund, Matching Grant and Osteoporosis and Endocrine Research Fund of
the University of Hong Kong. 相似文献
100.
B. H. Mullin R. L. Prince I. M. Dick F. M. A. Islam D. J. Hart T. D. Spector A. Devine F. Dudbridge S. G. Wilson 《Osteoporosis international》2008,19(7):961-968
SUMMARY: The 1p36 region of the human genome has been identified as containing a QTL for BMD in multiple studies. We analysed the TNFRSF1B gene from this region, which encodes the TNF receptor 2, in two large population-based cohorts. Our results suggest that variation in TNFRSF1B is associated with BMD. INTRODUCTION: The TNFRSF1B gene, encoding the TNF receptor 2, is a strong positional and functional candidate gene for impaired bone structure through the role that TNF has in bone cells. The aims of this study were to evaluate the role of variations in the TNFRSF1B gene on bone structure and osteoporotic fracture risk in postmenopausal women. METHODS: Six SNPs in TNFRSF1B were analysed in a cohort of 1,190 postmenopausal Australian women, three of which were also genotyped in an independent cohort of 811 UK postmenopausal women. Differences in phenotypic means for genotype groups were examined using one-way ANOVA and ANCOVA. RESULTS: Significant associations were seen for IVS1+5580A>G with BMD and QUS parameters in the Australian population (P = 0.008 - 0.034) and with hip BMD parameters in the UK population (P = 0.005 - 0.029). Significant associations were also observed between IVS1+6528G>A and hip BMD parameters in the UK cohort (P = 0.0002 - 0.003). We then combined the data from the two cohorts and observed significant associations between both IVS1+5580A>G and IVS1+6528G>A and hip BMD parameters (P = 0.002 - 0.033). CONCLUSIONS: Genetic variation in TNFRSF1B plays a role in the determination of bone structure in Caucasian postmenopausal women, possibly through effects on osteoblast and osteoclast differentiation. 相似文献