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991.
Age-related changes in bone biochemical markers and their relationship with bone mineral density in normal Chinese women 总被引:1,自引:0,他引:1
Pi YZ Wu XP Liu SP Luo XH Cao XZ Xie H Liao EY 《Journal of bone and mineral metabolism》2006,24(5):380-385
Measurements of bone biochemical markers are increasingly being used to evaluate the state of bone turnover in the management
of bone metabolic diseases, especially osteoporosis. However, changes in the bone turnover rate vary with age. The aim of
this study was to establish the laboratory reference range of serum bone-specific alkaline phosphatase (sBAP), serum type
I collagen cross-linked C-terminal telopeptide (sCTx), and urine CTx (uCTx), based on values from 665 healthy Chinese women
aged 20–80 years. We measured the levels of sBAP, sCTx, serum alkaline phosphatase (sALP), and uCTx and evaluated the age-related
changes and their relationship with bone mineral density (BMD) in the anteroposterior (AP) lumbar spine, hip, and left forearm.
We found significant correlations between biochemical markers and age, with coefficients of determination (R
2) of 0.358 for sBAP, 0.126 for sCTx, 0.125 for uCTx, and 0.336 for sALP. The net changes in different biochemical markers
were inversely correlated with the rates of BMD loss in the AP lumbar spine. After correction for age, body weight, and height,
the levels of the markers had significant negative correlations with the BMD of the AP lumbar spine, femoral neck, and ultradistal
forearm. All four biochemical markers had the highest negative correlation with BMD of the AP lumbar spine (partial correlation
coefficients of −0.366, −0.296, −0.290, and −0.258 for sBAP, sCTx, uCTx, and sALP, respectively). The mean and SD values of
these markers in premenopausal and postmenopausal women with normal BMD values were used as the normal reference ranges. The
reference ranges of sBAP, sCTx, and uCTx for pre- vs postmenopausal women were 17.3 ± 6.23 vs 18.9 ± 7.52 U/l, 3.18 ± 1.49
vs 3.23 ± 1.57 nmol/l, and 15.5 ± 11.4 vs 16.2 ± 12.4 nM bone collagen equivalents/mM urinary creatinine, respectively. Levels
of the bone formation marker (sBAP) and bone resorption markers (sCTx, uCTx) increased rapidly in women with osteopenia or
osteoporosis, indicating that they may be sensitive markers to determine the bone turnover rate in healthy Chinese women. 相似文献
992.
Influence of CYP3A5 gene polymorphisms of donor rather than recipient to tacrolimus individual dose requirement in liver transplantation 总被引:3,自引:0,他引:3
BACKGROUND: Tacrolimus is a widely used immunosuppressant in organ transplantation, but it is characterized by a narrow therapeutic index and high interindividual variations of its pharmacokinetics. Tacrolimus is a substrate for CYP3A. It has been conjectured that CYP3A5 polymorphism is associated with tacrolimus pharmacokinetic variations. The objective of this study was to evaluate the contribution of polymorphisms of the donor and recipient CYP3A5 gene on tacrolimus disposition in liver transplantation. METHODS: Fifty-three liver transplant recipients treated with tacrolimus were enrolled in this study. Tacrolimus dosage and blood trough concentration were investigated at 1 week, 2 weeks, and 1 month after transplantation. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was applied to determine the genotype of CYP3A5 gene. RESULTS: The concentration/dose (C/D) ratios in patients with *1/*1(*1/*3) genotype donor were significantly lower than in patients with *3/*3 genotype donor at 2 weeks (P = 0.036) and 1 month (P = 0.021), but not at 1 week posttransplantation. Combination analysis showed that such significance still existed between CYP3A5 expressor group and nonexpressor group for both donor and recipient genotype. Also differences of C/D ratio between CYP3A5 expressor and nonexpressor donors in nonexpressor recipients were larger than those between recipients in nonexpressor donors. CONCLUSION: The large interindividual variation of tacrolimus dose requirement is influenced by the metabolic activity of CYP3A5. Polymorphisms of the donor CYP3A5 gene seem to contribute more to such variation than the recipient. A larger population and further studies are needed to explore the exact mechanisms for tacrolimus pharmacokinetics. 相似文献
993.
Xie F Li SC Roos EM Fong KY Lo NN Yeo SJ Yang KY Yeo W Chong HC Thumboo J 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2006,14(11):1098-1103
OBJECTIVE: To cross-culturally adapt and validate Singapore English and Chinese versions of the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients with knee osteoarthritis (OA) in Singapore. METHODS: Singapore English and Chinese versions were cross-culturally adapted from the source English KOOS following standard guidelines (including cognitive debriefing). Patients were asked to complete identical questionnaires containing the KOOS, Short Form 36 Health Survey, and EQ-5D twice within 6 days. Reliability was assessed using Cronbach's alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations and convergent and divergent construct validity using 14 and 13 a priori hypotheses, respectively. RESULTS: Singapore English and Chinese KOOS versions were well accepted by patients in pilot testing and were therefore administered to a consecutive sample of 127 English and 131 Chinese-speaking Singaporeans with knee OA. Cronbach's alpha exceeded 0.7 for all domains except for Chinese pain and symptoms domains. ICC exceeded 0.7 for all domains except for English sport and recreation and Chinese knee-related QoL domains. Hypothesized item-to-domain correlations (Spearman's rho>or=0.4) were observed for 38 items in English and 29 in Chinese versions. Convergent construct validity was supported by the presence of hypothesized moderate/strong correlations (rho=0.37-0.65) for 13 and 11 a priori hypotheses in the English and Chinese KOOS, respectively. Divergent construct validity was supported by the presence of weak correlations (rho=0.02-0.34) for 12 and 11 a priori hypotheses in the English and Chinese KOOS, respectively. CONCLUSION: The Singapore English and Chinese KOOS were well accepted and demonstrated acceptable reliability and validity in Asian patients with knee OA in Singapore. 相似文献
994.
Low-level mechanical vibrations can influence bone resorption and bone formation in the growing skeleton 总被引:3,自引:0,他引:3
Short durations of extremely small magnitude, high-frequency, mechanical stimuli can promote anabolic activity in the adult skeleton. Here, it is determined if such signals can influence trabecular and cortical formative and resorptive activity in the growing skeleton, if the newly formed bone is of high quality, and if the insertion of rest periods during the loading phase would enhance the efficacy of the mechanical regimen. Eight-week-old female BALB/cByJ mice were divided into four groups, baseline control (n = 8), age-matched control (n = 10), whole-body vibration (WBV) at 45 Hz (0.3 g) for 15 min day(-1) (n = 10), and WBV that were interrupted every second by 10 of rest (WBV-R, n = 10). In vivo strain gaging of two additional mice indicated that the mechanical signal induced strain oscillations of approximately 10 microstrain on the periosteal surface of the proximal tibia. After 3 weeks of WBV, applied for 15 min each day, osteoclastic activity in the trabecular metaphysis and epiphysis of the tibia was 33% and 31% lower (P <0.05) than in age-matched controls. Bone formation rates (BFR.BS(-1)) on the endocortical surface of the metaphysis were 30% greater (P <0.05) in WBV than in age-matched control mice but trabecular and middiaphyseal BFR were not significantly altered. The insertion of rest periods (WBV-R) failed to potentiate the cellular effects. Three weeks of either WBV or WBV-R did not negatively influence body mass, bone length, or chemical bone matrix properties of the tibia. These data indicate that in the growing skeleton, short daily periods of extremely small, high-frequency mechanical signals can inhibit trabecular bone resorption, site specifically attenuate the declining levels of bone formation, and maintain a high level of matrix quality. If WBV prove to be efficacious in the growing human skeleton, they may be able to provide the basis for a non-pharmacological and safe means to increase peak bone mass and, ultimately, reduce the incidence of osteoporosis or stress fractures later in life. 相似文献
995.
Tissue Inhibitor of Matrix Metalloproteinase-1 Suppresses Apoptosis of Mouse Bone Marrow Stromal Cell Line MBA-1 总被引:3,自引:0,他引:3
Guo LJ Luo XH Xie H Zhou HD Yuan LQ Wang M Liao EY 《Calcified tissue international》2006,78(5):285-292
We investigated the action of tissue inhibitor of metalloproteinase-1 (TIMP-1) on apoptosis and differentiation of mouse bone
marrow stromal cell line MBA-1. TIMP-1 did not affect alkaline phosphatase (ALP) activity, suggesting that it is not involved
in osteoblastic differentiation in MBA-1 cells. However, TIMP-1 inhibited MBA-1 apoptosis induced by serum deprivation in
a dose-dependent manner. Our study also showed increased Bcl-2 protein expression and decreased Bax protein expression with
TIMP-1 treatment. TIMP-1 decreased cytochrome c release and caspase-3 activation in MBA-1 cells. TIMP-1 activated phosphatidylinositol 3-kinase (PI3-kinase) and c-Jun N-terminal
kinase (JNK), and the PI3-kinase inhibitor LY294002 or the JNK inhibitor SP600125 abolished its antiapoptotic activity. To
investigate whether antiapoptotic action of TIMP-1 was mediated through its inhibition on MMP activities, we constructed mutant
TIMP-1 by side-directed mutagenesis, which abolished the inhibitory activity of MMPs by deletion of Cys1 to Ala4. Wild-type
TIMP-1 and mutant TIMP-1 expression plasmids were transfected in MBA-1 cells, and results showed that mutant TIMP-1 still
protected the induced MBA-1 cell against apoptosis. These data suggest that TIMP-1 antiapoptotic actions are mediated via
the PI3-kinase and JNK signaling pathways and independent of TIMP-1 inhibition of MMP activities.
L.-J. Guo and X.-H. Luo this authors contributed equally to this work. 相似文献
996.
Huang J Zhang TL Xu SJ Li RC Wang K Zhang J Xie YN 《Calcified tissue international》2006,78(4):241-247
The application of lanthanum (La) in industry, medicine, and agriculture may cause accumulation of the element in human body.
This article examines the effects of La on the femur bone mineral of male Wistar rats after administration of La(NO3)3 by gavage at the dose of 2.0 mg La(NO3)3 · kg−1 · day−1 over a 6-month period. Chemical analysis confirmed La accumulation in bone and loss in bone mineral. Thermogravimetric analysis
showed a decrease in the mineral-to-matrix ratio and an increase in carbonate content. Fourier-transform infrared spectrometry
revealed elevation in the contents of labile carbonate and acidic phosphate. The synchrotron radiation small-angle X-ray scattering
study presented a smaller mean thickness of the mineral crystals in the bone of La-treated rats. The synchrotron radiation-extended
X-ray absorption fine structure analysis indicated that the La treatment resulted in a lowered disorder in the crystals. The
smaller size, more adsorbed labile carbonate, and more acidic phosphate made the bone mineral easier to dissolve, as revealed
in the kinetic measurement of bone demineralization. These findings suggest that La retards bone maturation of rats. 相似文献
997.
Xie X Eberding A Madera C Fazli L Jia W Goldenberg L Gleave M Guns ES 《The Journal of urology》2006,175(5):1926-1931
PURPOSE: We explored the efficacy of the ginsenoside Rh2 and examined its impact on the effective dose of paclitaxel and mitoxantrone in the LNCaP prostate tumor model. MATERIALS AND METHODS: Cultured LNCaP cell viability was assessed following treatment (48 hours) with Rh2 (0 to 40 microM) alone or in combination with paclitaxel and mitoxantrone. Synergism or antagonism observed when combining treatment was calculated using CalcuSyn software (Biosoft). In addition, the inhibition of LNCaP human xenograft tumor growth was examined in vivo when Rh2 treatment was combined with chemotherapy. Harvested tumors were immunohistochemical stained with p27kip and Ki67. RESULTS: Rh2 and paclitaxel act synergistically in cultured LNCaP cells to lower ED50 and ED75 values. Rh2 and mitoxantrone are also synergistic. However, when combined as ED95, an antagonistic effect was observed in this cell line. Treatment of LNCaP tumors by Rh2 plus paclitaxel produced a significant decrease in tumor growth and serum prostate specific antigen. Immunohistochemical analysis revealed an apparent but nonsignificant effect on proliferation markers in LNCaP tumors. When Rh2 and mitoxantrone were combined in vivo, there was no significant benefit observed. CONCLUSIONS: These results indicate that the combination of Rh2 and paclitaxel has an effect on growth inhibition that is greater and synergistic, as demonstrated in a cultured LNCaP cell line. Conversely combining Rh2 with mitoxantrone appears to elicit no benefit. Therefore, combination therapy using chemotherapy and Rh2 requires further investigation. 相似文献
998.
目的探讨膀胱移行细胞癌中成纤维细胞生长因子3(FGF3)基因的表达与扩增及其临床病理学意义。方法运用免疫组化和荧光原位杂交方法,结合组织芯片技术,检测FGF3在100例膀胱移行细胞癌和30例癌旁正常膀胱黏膜组织中的表达与扩增情况,结合肿瘤的临床病理学资料,分析它们之间的相关性。结果免疫组化结果显示,全部正常膀胱黏膜组织均呈FGF3蛋白阴性反应;在89例有效检测的膀胱移行细胞癌中,有20例(22%)出现FGF3阳性表达,而且明显多见于分化程度低(G3级)、浸润中晚期(T2-4期)或瘤体直径≥3cm的肿瘤(均P〈0.05)。本组FISH检测发现,在63例有效膀胱移行细胞癌中,有10例(16%)被检测到FGF3基因扩增,而且与肿瘤的大小和临床分期均有显著的相关性(均P〈0.05)。另外,10例FGF3基因扩增的膀胱癌均呈FGF3蛋白阳性表达;而剩下的53例无FGF3扩增的肿瘤中,只有3例(6%)出现FGF3蛋白阳性反应。结论FGF3蛋白在膀胱移行细胞癌中的表达上调与该肿瘤的恶性临床病理学表型密切相关,可能参与了部分肿瘤的恶性发展进程;膀胱移行细胞癌中FGF3基因扩增是其编码的FGF3蛋白表达上调的主要机制。 相似文献
999.
Currently, surgery-oriented treatment plays a major role in the treatment of ovarian cancer patients. But 5-year survival rate of patients is still around 30%. One of the main reasons for the Iow survival rate is the drug resistance of tumor cells against chemotherapy.1,2 The function of antiapoptosis in the course of initiation and progress of cancer has a close relationship with drug resistance of tumor cells. Survivin is a new discovered anti-apoptosis gene, its expression levels correlating with more aggressive disease and poor clinical outcome in many of these tumors. It has been reported that survivin is expressed during fetal development and in cancer tissues.3 Furthermore,survivin overexpression, by disrupting the balance between cell proliferation/differentiation and apoptosis, may relate with the resistance to a variety of apoptotic stimuli, including chemotherapy.4,5 We designed antisense oligonucleotides of survivin to treat the drug-resistant human ovarian carcinoma cell line COC1/DDP, and studied its effects on inducing COC1/DDP apoptosis. The purpose of this study was to find a novel approach to improve the sensitivity of ovarian carcinoma chemotherapy. 相似文献
1000.
The vascular endothelial growth factor expression and vascular regeneration in infarcted myocardium by skeletal muscle satellite cells 总被引:9,自引:2,他引:7
Skeletal satellite cell normally lies in a quiescent state under the basal membrane of skeletal muscular fibers. Once injury occurred, it will rapidly mobilize, proliferate and fuse to repair the damaged fiber.1 Skeletal myoblast transplantation has been shown to improve cardiac function in infarcted myocardium models. Vascular endothelial growth factor (VEGF) is a promising reagent for inducing myocardial angiogenesis and hypoxia is also a major inducer of VEGF expression. Some studies pr… 相似文献