成骨不全家系一个新的Ⅰ型胶原α1链蛋白基因突变

目的 对Ⅰ型胶原α1链蛋白基因（COL1A1基因）进行测序研究，旨在寻找已知或未知的COL1A1基因突变位点，探讨我国成骨不全的发病机制。方法 研究一常染色体显性遗传成骨不全家系的临床特征，设计引物对家系中患者和正常人的COL1A1基因外显子进行扩增和测序分析，同时对群体中无血缘关系的50名健康对照者进行限制性内切酶分析。结果 发现家系中成骨不全患者COL1A1基因的第3470位点的碱基G→A的突变，导致G1157D，而在家系内非患者及正常对照者中均无发现。结论 COL1A1基因突变也是中国人群中成骨不全致病原因之一，现发现的突变属成骨不全一个新的致病基因突变。甘氨酸转变成天冬氨酸的这种突变对成骨不全表型具有重要的影响。     

电穿孔介导的基因治疗对兔下颌骨牵引区新生骨骨密度与强度的影响

目的 探索电穿孔介导的基因治疗对下颌骨DO过程中牵引间隙新生骨密度与强度的影响,从而为促进下颌骨DO新骨生成,缩短牵引周期,减少并发症提供新思路.方法 以新西兰大白兔为实验动物模型,于术后3 d开始下颌骨牵引,每天0.8 mm,连续牵引7 d后,将实验动物分为5组.A组:在牵引区注射2 μg(O.1μg/μl)重组质粒pIRES-hVEGF165-hBMP2;B组:在牵引区注射2 μg(0.1μg/μl)重组质粒pIRES-hBMP2;C组:在牵引区注射2 μg(0.1μg/μl)重组质粒pIRES-hVEGF165;D组:在牵引区注射2 μg(0.1μg/μl)空质粒pIRES;E组:在牵引区注射相同剂量的生理盐水.5组实验动物均施加电穿孔刺激.各组分别于固定期第1、2、4、8周行X线及QCT检查.选整个牵张间隙新生骨痂部分为兴趣区,测定骨密度.然后处死动物.取材测量牵引区新生骨的三点抗压强度.结果 A、B、C组新生骨痂密度各时相点新生骨痂密度明显高于D、E组(P<0.01).固定2周,A组明显高于各组,但B、c组间比较差异无统计学意义.固定4周,A、B组明显高于C、D、E组(P<0.01).固定8周A组明显高于B、c、D、E组(P<0.01).B、C组间比较差异无统计学意义,但高于D、E组(P<0.01).固定4周,A组新生骨的三点抗压强度明显高于B、C、D、E组(P<0.01).固定8周,A组仍明显高于各组(P<0.01),且B组也明显高于c、D、E组(P<0.05).结论 电脉冲介导的pIRES-hVEGF165-hBMP2重组质粒体内转染可使牵引区获得较满意的骨再生和骨化成熟进程,其新骨骨化、改建过程均超过对照组.提示联合应用BMP与VEGF,可能会实现成骨与血供的联合重建,并且使单一生长因子的效应放大,使骨愈合的速度加快.     

Temporary brittle bone disease: fractures in medical care

Temporary brittle bone disease is the name given to a syndrome first reported in 1990, in which fractures occur in infants in the first year of life. The fractures include rib fractures and metaphyseal fractures which are mostly asymptomatic.
The radiological features of this disorder mimic those often ascribed to typical non-accidental injury. The subject has been controversial, some authors suggesting that the disorder does not exist.
This study reports five infants with typical features of temporary brittle bone disease in whom all or most of the fractures took place while in hospital. A non-accidental cause can be eliminated with some confidence, and these cases provide evidence in support of the existence of temporary brittle bone disease.     

Cytotoxic agents are detrimental to bone formed by distraction osteogenesis

Distraction osteogenesis can be used to replace segmental bone loss when treating malignant bone tumors in children and adolescents. These patients often receive cytotoxic chemotherapy as part of their treatment regimen. The effect of cytotoxic drugs on the cellular processes during distraction osteogenesis and the structural and mechanical properties of regenerate bone is unknown. We therefore used a rabbit model of distraction osteogenesis to determine that cytotoxic agents had a detrimental effect on regenerate bone formed by this technique. We administered adriamycin and cisplatinum to 20 rabbits using two different simulated chemotherapy regimens. All rabbits underwent an osteotomy at 12 weeks of age. Distraction osteogenesis began 24 h later at a rate of 0.75 mm a day for 10 days, followed by 18 days without correction to allow for consolidation. Regenerate bone was assessed using plain radiographs, bone densitometry, and mechanical testing. Peri-operative chemotherapy decreased the mechanical properties of the regenerate with regard to yield strain (3.7 × 10⁻² vs. 5.2 × 10⁻²) and energy at yield (2.73 × 10⁷ vs. 3.92 × 10⁷). Preoperative chemotherapy in isolation reduced bone mineral density (0.38 vs. 0.5 g/cm²), bone mineral content (0.24 vs. 0.36 g), and volumetric bone mineral density (0.57 vs. 0.65 g/cm²) with no alterations in the mechanical properties. Conclusions: Preoperative chemotherapy appears to decrease the volume of regenerate bone, without affecting structural integrity, suggesting that the callus formed is of good quality. The converse appears true for peri-operative chemotherapy.     

Biochemical bone markers in the assessment and pamidronate treatment of children and adolescents with osteogenesis imperfecta

Aim: To assess the role of biochemical bone markers in classification of children with osteogenesis imperfecta (OI), their possible association with vertebral compression fractures in milder forms of OI and their role in monitoring of intravenous pamidronate (APD) treatment. Methods: Serum total alkaline phosphatase (ALP), bone ALP isoforms (in a subgroup), osteocalcin, type I procollagen carboxy‐terminal propeptide, carboxy‐terminal telopeptide of type I collagen, and urine deoxypyridinoline (DPD) were measured in a cross‐sectional study of 130 untreated individuals, 0.25–20.9 years (median 6.7), with OI types I, III and IV. Of those, sixty‐nine were also assessed longitudinally during monthly APD treatment. Bone mineral density (BMD) was measured by dual‐energy X‐ray absorptiometry. Results: Significant differences in bone markers, however not sufficient for individual clinical use, were found in the larger untreated group but not between subgroups with or without vertebral compressions. All bone markers decreased during treatment for 1.0–12.5 years, but with different relative amounts. Changes were not correlated to the improvement in BMD, mobility or pain. Conclusion: Bone markers are, despite significant differences, not useful for the classification of OI type in the individual child and are not associated with vertebral compressions. Serum ALP and urinary DPD are sensitive in monitoring bisphosphonate treatment.     

颅骨牵张术中新骨骨密度的定量评价

目的:探讨颅骨牵张术修复骨缺损过程中新骨骨密度的评价方法。方法:成年健康山羊18只,颅顶区制备25mm×10mm全层颅骨缺损,随机分为实验组和对照组,实验组15只建立牵张术修复颅骨缺损的动物模型,于牵张结束后2,4,6周分别处死5只动物,对照组3只动物与实验组牵张后6周动物同期处死,QCT、DEXA两种方法测量新骨骨密度,比较两种测量方法骨密度值(BMD)及相关性。结果:实验组QCT测量牵张间隙各兴趣区BMD值较前一时段对应BMD值明显增加(P<0.05),同一牵张间隙内各固定时段两端(R2、R3)较中央(R1)BMD值明显高(P<0.05),R2、R3之间无明显差别(P>0.05);DEXA测量固定期4周,各兴趣区BMD值较固定2周对应BMD值明显增加(P<0.05),而固定期6周,仅牵张间隙中央(R1)较固定4周对应BMD值增加有统计学意义(P<0.05),同一牵张间隙内固定期2,4周两端(R2、R3)较中央(R1)BMD值明显高(P<0.05);两种检测方法测得平均骨密度值在各时段均存在正相关(P<0.005);对照组缺损区QCT、DEXA检测未显示有新骨形成。结论:两种检测方法均能反映牵张过程新骨骨密度变化,QCT不受解剖结构和牵张器形状的影响,更适于颅面骨牵张术新骨形成的监测评价。     

狗骨髓基质细胞的分离培养及成骨潜能的研究

目的观察狗骨髓基质细胞(MSCs)的生长特点及诱导条件下的成骨能力,为利用狗的MSCs进行成骨研究提供实验基础。方法从成年狗胫骨取骨髓进行MSCs培养,检测细胞周期;应用四甲基偶氮唑蓝(MTT)比色法观察细胞增殖;测定碱性磷酸酶活性;用Von Kossa染色法观察钙化结节。观察在条件培养液中MSCs生长及成骨分化情况。结果MSCs增殖能力强,细胞周期显示有20%的细胞处于G0/G1期。诱导条件下的细胞碱性磷酸酶活性明显增高,10~12 d达到高峰,并出现钙化结节。结论体外培养狗的MSCs具有分化成骨的潜能,增殖能力强,可作为骨组织工程的种子细胞。     

A Fourier transform infrared spectroscopic and solid-state NMR study of bone mineral in osteogenesis imperfecta

Fourier transform infrared spectroscopy and ³¹P solid-state nuclear magnetic resonance spectroscopy were used to determine if any structural or compositional differences in osteogenesis imperfecta (OI) bone mineral could be detected that might help to explain the bone fragility observed in this disease. A previous study by Cassella et al. used an electron probe X-ray microanalytical technique to compare the calcium to phosphorus (Ca/P) molar ratios in normal bone and bone from patients with OI. It was demonstrated that bone from OI patients had a lower Ca/P molar ratio. This study demonstrated that OI bone mineral had a general hydroxyapatite structure and that isomorphous substitutions in the carbanoapatite lattice could account for the low Ca/P molar ratio. Received: December 28, 1999 / Accepted: March 22, 2000     

Osteogenesis imperfecta: profiles of motor development as assessed by a postal questionnaire

This study was performed to achieve more detailed information regarding the age and sequence in the development of motor milestones in the different types of osteogenesis imperfecta (OI). The parents of 98 patients with a diagnosis of OI were sent a questionnaire regarding the age at which patients achieved motor milestones. All patients were attending the outpatient clinic for children with OI at the Wilhelmina Children's Hospital. The motor milestones were classified into static motor milestones and dynamic motor milestones and all data were checked with health care records. The age of development of motor milestones was compared to reference values of the healthy population. The severity of the disease was classified according to Sillence based on clinical, genetic and radiological data. The age of intramedullary rodding of the first nail in the lower and upper extremity and the localisation was noted. A total of 76 parents responded to the 98 questionnaires (78%). In OI type I, a delay exists in achieving motor milestones, comparable to the 95th percentile of the normal population. In type III, the development of all motor milestones was significantly delayed compared to types I and IV with a discrepancy between static and dynamic milestones. In OI type IV, a retardation in motor development developed after the milestone `sitting without support' was achieved. Motor development in types I and IV was not influenced by intramedullary rodding of the lower extremities, since rodding was rarely performed before the milestone `unsupported standing' was achieved. In type III, the influence of intramedullary rodding on the age of achieving motor milestones remains questionable. Conclusion The severity of osteogenesis imperfecta has a large influence on the age and sequence in the development of motor milestones. No influence of intramedullary rodding of the lower extremities on motor development was found in osteogenesis imperfecta types I and IV, whereas the influence in type III remains questionable. Received: 11 November 1999 and in revised form: 9 February 2000 and 24 February 2000 Accepted: 24 February 2000     

家族性成骨不全症2例报告

目的总结帕米膦酸钠在成骨不全症中的应用经验。方法对2007年我院收治的2例成骨不全症的治疗进行回顾分析。结果两例对帕米膦酸钠有较好耐受性。治疗随访期间未再发骨折。结论帕米膦酸钠对成骨不全症有较好疗效，但需更多病例观察。