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21.
BackgroundMedical and surgical interventions to prevent or reduce bone deformities and improve gait in children with cerebral palsy (CP) are based on empirical evidence that there is a relationship between bone deformities and gait deviations.Research questionWhat is the relationship between tibial-femoral bone morphology and kinematic gait variables in ambulant children with CP?MethodsA retrospective analysis was conducted on data from 121 children with uni- (n = 64, mean age 9.9 (SD 3.4) years) and bi- lateral (n = 57, mean age 10.4 (SD 3.6) years) CP who had undergone 3D gait analysis and biplanar X-rays (EOS® system). The limbs were split as DIP (the more impaired limb of children with bilateral CP), HEMI (the impaired limb of unilateral CP) and REF (the unimpaired limb of unilateral CP). Multi-variable Linear Regressions were performed between 23 kinematic variables, the Gait Deviation Index (GDI) and a model composed of nine 3D bone variables for each limb type.ResultsWhen the whole sample was pooled, 72% of R2 values were poor, 16% were fair, and 12% were moderate. Lower limb bone morphology models explained less than 1% of GDI variability. Correlations between tibial-femoral rotational parameters and hip rotation were mostly poor. Mean foot progression angle was the only kinematic parameter that was fairly to moderately correlated with bone variables in the 3 limb types. A tibial-femoral bone model explained 48% of the variability of mean foot progression angle in the REF limbs, 31% in the HEMI limbs and 25% in the DIP limbs.SignificanceTibial-femoral bone morphology was only weakly related to kinematic gait variables, in contrast with common clinical assumptions. These results suggest that factors other than bone morphology influence gait quality and thus a thorough clinical examination and gait analysis is required prior to making treatment decisions.  相似文献   
22.

Background

Radium 223 was introduced for metastatic castration-resistant prostate cancer based on the results of a randomized controlled trial showing risk reduction for death and skeletal events. Our aim was to evaluate the outcome of patients receiving radium 223 in a real-world setting.

Patients and Methods

We conducted a multicenter retrospective analysis in the Triveneto region of Italy.

Results

One hundred fifty-eight patients received radium 223 in our region. After a median follow-up of 9.5 months, 75 patients died. The median overall survival (OS) was 14.2 months, and the median progression-free survival (PFS) was 6.2 months. Seventy-one (45%) patients achieved progression as best response. Thirty-seven (23%) patients stopped the treatment early because of progression. Eastern Cooperative Oncology Group performance status was prognostic for OS (18.4 vs. 12.3 vs. 7.5 months; 0 vs. 1, P = .0062; 0 vs. 2, P = .0002), whereas previous prostatectomy or docetaxel exposure were not. A neutrophil to lymphocytes ratio ≥ 3 significantly impacted OS (18.1 vs. 9.7 months; P < .001) and slightly impacted PFS (6.6 vs. 5.6 months; P = .05). Patients with a baseline alkaline phosphatase (ALP) value ≥ 220 U/L had worse OS and PFS (24.1 vs. 10.5 months; 7.2 vs. 5.5 months; P < .001). Patients with changes in ALP value achieved better OS (P = .029) and PFS (P = .002). There was no difference according to the line of therapy (0 vs. ≥ 1; P = .490). The main grade 3/4 toxicities were anemia, asthenia, and thrombocytopenia.

Conclusion

This large real-world report confirms comparable OS and PFS data when compared with the pivotal study, as well as the predictive role of ALP and neutrophil to lymphocytes ratio. The definition of the optimal position of radium 223 in the treatment of metastatic castration-resistant prostate cancer has still to be defined.  相似文献   
23.

Background and aims

Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.

Methods and results

In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.

Conclusion

SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE.  相似文献   
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During skeletal development the two ossification centers of the odontoid process are separated from the corpus of the axis by a subdental synchondrosis. This synchondrosis is thought to close and disappear spontaneously in adolescence although this has never been studied in detail. The basis of the dens is of clinical relevance as type II dens fractures are located here. To characterize the morphological architecture of the axis with particular attention to the subdental synchondrosis, the complete axis was harvested from thirty age-matched and gender-matched patients of the three different age groups at autopsy. The subdental synchondrosis and the bone structure of the dens, the basis of the dens and the body of C2 were analyzed by radiography, histology and quantitative histomorphometry. At the macroscopic level the persistency of the subdental synchondrosis in the adult cervical spine was detected in 87% (26 of 30) of the specimens. Histomorphometry revealed a residual disc blastema with an average size of 25.8% of the sagittal depth of the basis of the dens at this level. Bony integration of the synchondrosis was poor throughout all ages. Histologically a cartilaginous matrix composition of the subdental synchondrosis persisted throughout all groups. The trabecular microarchitecture demonstrated a significant reduction of bone volume and trabecular number as well as an increased trabecular separation within the basis of the dens as compared to the corpus or the dens of C2. This histomorphometric data regarding a poor integration of the synchondrosis into the trabecular network and the reduced bone mass within the basis of the dens might offer a previously underestimated explanation for the occurrence of type II dens fractures and their association with pseudoarthrosis, respectively.Matthias Gebauer and Christian Lohse contributed equally to this study and therefore share first authorship.  相似文献   
27.
[目的]制备一种具有良好降解性和成骨活性、可注射的自凝固新型骨修复材料。[方法]制备携载rhBMP-2的聚乳酸与聚乙醇酸共聚物(PLGA)微球,并将其与rhBMP-2/磷酸钙骨水泥(CPC)复合,制备出rhBMP-2/PLGA微球/CPC复合人工骨。探讨了材料的特性,包括形貌、固化时间、抗压强度及反映材料体外降解速度的指标一体外降解液Ca、P浓度变化,测定复合材料rhBMP乏的释药速度及体外诱导MSCs细胞成骨分化的能力。[结果]与单纯CPC-rhBMP-2相比,复合材料的固化时间少量增加,抗压强度下降明显。体外降解速度及体外释药明显提高,释放的rhBMP-2具有骨诱导活性。[结论]rhBMP-2/PLGA微球/磷酸钙骨水泥新型复合人工骨是具有良好应用前景的骨修复材料。  相似文献   
28.
目的观察年龄因素对骨髓间充质干细胞(marrow mesenchymal stem cells, MSCs)成骨分化能力的影响;了解基因治疗对老年大鼠MSCs成骨分化能力的影响. 方法 1月龄(幼年组)、9月龄(成年组)及24月龄(老年组)雄性Wistar大鼠各6只,取MSCs经体外分离、培养及携带骨形成蛋白2(bone morphogenetic protein 2,BMP-2)基因的腺病毒载体(Ad-BMP-2)转染后,定量检测BMP-2、碱性磷酸酶(alkaline phosphate,ALP)表达,以及成骨细胞标志性蛋白:Ⅰ型胶原、骨涎蛋白(bone sialoprotein,BSP)和骨桥素(osteopontin, OPN)的表达.将转染的各组MSCs分别与磷酸三钙(tricalcium phosphate, TCP)复合后植入裸鼠体内,3周后取材,比较各组诱导异位成骨能力. 结果 ELISA检测表明BMP-2基因修饰的MSCs可以有效表达BMP-2,且表达量在各年龄组间差异无统计学意义(P>0.05);各组ALP于诱导后第9天达高峰,但组间差异均无统计学意义(P>0.05);诱导后第7天,RT-PCR半定量检测示各组均有成骨细胞特征性蛋白,即:Ⅰ型胶原、OPN及BSP的明显表达,表达量在各组间差异无统计学意义(P>0.05);BMP-2基因转染的MSCs与TCP复合后可诱导裸鼠体内异位成骨,各组成骨量差异无统计学意义(P>0.05). 结论 BMP-2基因修饰的老年大鼠MSCs可以恢复成骨分化能力,基因治疗可能为老年性骨骼疾病提供一种新的治疗途径.  相似文献   
29.
目的探讨血小板第4因子(platelet factor 4,PF4)对5.0 Gy γ射线全身照射小鼠的骨髓基质细胞(bone marrow stromal cells,BMSCs)的保护作用,进一步探讨PF4对造血的辐射防护机制.方法30只雄性小鼠随机分为3组:①放射组,②PF4保护组,③对照组.小鼠照射前分别于26和20 h腹腔内注射PF4,每次剂量50 μg/kg.于照射后3 d取骨髓细胞体外培养,分别计数培养后3、7和14 d的骨髓基质细胞集落(CFU-F);在培养后10 d流式细胞仪检测细胞周期.结果3组中,照射组3 d的CFU-F数量与PF4保护组差异无统计学意义,7和14 d的CFU-F数量PF4保护组较照射组明显增加.流式细胞仪检测结果表明3组中照射组G0+G1期细胞明显高于其余两组,S,G2+M期细胞明显低于其余两组.结论PF4对照射小鼠的骨髓基质细胞有保护作用,促进造血重建.  相似文献   
30.
目的探讨下颌骨缺损即刻植骨修复术后,伤口延期愈合的影响因素。方法将下颌骨即刻植骨分为Ⅰ期愈合组和延期愈合组,回顾性地查阅住院病历,按预先设计的表格填写有关项目。结果下颌骨即刻植骨的愈合与患者的年龄、受骨区是否有手术史、植骨的类型、植骨的大小无关;术中口内外相通是植骨延期愈合的主要因素。结论下颌骨良性病变即刻植骨修复时,应密切关注术区与口内外穿通情况,进行有针对性地处理,争取植骨Ⅰ期愈合。  相似文献   
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