多药耐药基因转染骨髓造血细胞移植小鼠的安全性研究

目的 探讨多药耐药基因(mdrl)转染骨髓造血细胞移植后,其在体内分布和安全性.方法 骨髓造血细胞转染mdrl基因后移植入BALB/C鼠,免疫组织化学和RT.PCR观察mdrl基因在骨髓、外周血及重要脏器的表达;监测外周血白细胞变化及重要脏器病检分析其安全性.结果 P-糖蛋白(P-gP)在骨髓表达率随时间降低,各时间组差异无统计学意义(x2=3.74,P＞0.05),在外周血表达第2月最高,为(9.95±1.84)%,各时间组差异无统计学意义(x2=2.31,P＞0.05),在重要脏器无表达;移植未转染组与移植转染组外周血白细胞计数至移植60 d后,两者差异有统计学意义(t=6.173,P＜0.05),病检除肝和肾有炎性渗出和水肿病变外,其余无异常.结论 mdrl基因在骨髓和外周血有持续较高表达,在重要脏器无表达;mdrl基因转染对造血恢复及重要脏器无明显影响.     

数字曲面体层X片在评价非负荷期种植体周围骨吸收的临床应用

目的:评价数字曲面体层X片在测量非负荷期种植体周围牙槽骨吸收的应用情况。方法:观测、分析对比26例患者50枚Camlog系统种植体临床应用非负荷期间数字化曲面体层X片和X线牙片上种植体周围牙槽骨吸收的情况。结果:50枚Camlog种植体植入后10 d,两种X片骨吸收测量结果分别为0.65 mm、0.81 mm,两者之间无明显差异;第4个月(或6月\下颌)分别为0.12 mm、0.19 mm,两者之间无明显差异。结论:本研究显示数字化曲面体层X片在测量非负荷期种植体周围牙槽骨吸收的应用中有操作简单、重复性好、精确度高、变形可补偿等优点,有实际应用价值,值得推广。     

Bone growth patterns in Chinese children and adolescents: a 6-year follow-up study provides evidence for sexual dimorphism and tracking

Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.     

同种异体骨支撑架微创治疗股骨头坏死的临床研究

目的应用改良髓芯减压术结合同种异体骨支撑架加自体骨和脱钙骨基质（decalcified bone matrix，DBM）治疗早期股骨头坏死，探索早期股骨头坏死的微创治疗方法。方法2004年1月～2005年4月，23例24个髋关节采用经大转子下通过股骨颈钻隧道至股骨头骨坏死区，将装有自体松质骨和DBM的同种异体骨支撑架经隧道拧入骨坏死区直至软骨下骨约5mm处，隧道远端用自体髂骨填塞。观察手术前后Harris评分变化、x线影像学表现及是否需进一步治疗。结果本组所有患者均获得随访，平均随访19（12—27）个月，以最后一次随访资料作为最终评价依据。Harris评分，术前优良率为43．5％（10／23）。术后优良率为91．3％（21／23）。22侧髋关节影像学表现保持稳定，无明显并发症发生。结论同种异体骨支撑架植入结合自体松质骨和DBM治疗成人股骨头坏死，增加了股骨头负重区软骨下骨的机械支撑，成骨作用强，有利于股骨头坏死的修复与重建，同时，不破坏患者股骨头本身的血液供应，创伤小，操作简单，值得临床推广使用。     

重组人骨形态发生蛋白4基因腺相关病毒载体对兔骨髓基质干细胞生物学行为的影响

目的应用重组人骨形态发生蛋白4基因腺相关病毒载体(AAV-hBMP4)转染兔骨髓基质干细胞(BMSCs),观察其对BMSCs生物学行为的影响,从而为骨组织工程寻找理想的病毒载体及种子细胞。方法全骨髓法培养兔BMSCs,按感染复数(MOI)值不同设定为四组,分别转染兔BMSCs,观察病毒量对细胞形态的影响。选取影响最小的MOI值,进行后续实验。转染兔BMSCs,MTT法描记细胞生长曲线,观察AAV对细胞增殖活性的影响。以重组增强型绿色荧光蛋白基因的腺相关病毒载体(AAV-EGFP)为参照,行流式细胞仪检测,计算转染效率。AAV-hBMP4与对照病毒AAV-EGFP分别转染细胞,观察细胞形态,行碱性磷酸酶(ALP)染色、Von Kossa染色及ALP含量测定,观察成骨活性。兔肌袋实验观察异位成骨情况。结果MOI值为5×10~4 vg/cell时,AAV对细胞形态影响最小,以此值进行后续实验。AAV转染后,细胞增殖活性良好,转染效率为55％～65％。AAV-hBMP4转染后,细胞形态呈现典型的成骨改变,ALP染色及Von Kossa染色均出现成骨的特征性改变,而AAV-EGFP组无上述改变。细胞上清ALP含量测定显示,实验组ALP含量显著增高,与对照组比较差异有统计学意义(t=218．65,P＜0．01)。兔肌袋实验术后4周组织学检测可见大量钙盐沉积,矿化结节形成。结论AAV-hBMP4转染效率高,对BMSCs的增殖活性影响小,AAV-hBMP4转染的BMSCs可望成为组织工程化骨的理想种子细胞。     

Association of ex-vivo expanded human mesenchymal stem cells and rhBMP-7 is highly effective in treating critical femoral defect in rats

Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate the best dosage.     

18F-FDG符合线路显像与同机CT融合在肿瘤诊断的应用

【目的】评价~(18)F-FDG符合线路显像及同机CT图像融合在肿瘤诊断中的价值。【方法】经病理确诊或临床确诊为恶性肿瘤的病人79例,良性肿块病人19例进行~(18)F-FDG符合线路显像及同机CT图像融合检查,经COSEM重建,结果与解剖显像比较。【结果】①~(18)F-FDG符合显像诊断恶性肿瘤的敏感性、特异性、准确率、阳性预测值和阴性预测值分别为92.4％、89.5％、91.8％、97.3％和73.9％,解剖显像分别为79.8％、63.2％、76.5％、90.0％和42.9％。②同部位显像比较中,~(18)F-FDG显像病灶探测数为302个,而解剖显像为286个。③同机CT融合明显提高对肺部近纵隔、膈缘及腹部等部位的定位诊断。【结论】~(18)F-FDG符合线路显像较解剖显像更好地对恶性肿瘤作出鉴别诊断,并且能探测到更多的恶性病灶,同机CT融合较大地提高定位诊断的准确性,具有重要的临床价值,值得临床广泛应用。     

Electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic ischemic heart disease

BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium.     

骨胶原与骨质疏松骨密度及骨生物力学的相关性研究

目的探讨骨胶原含量在绝经后骨质疏松症的发生、发展及在骨质疏松性骨折中的作用。方法取7个月龄未交配雌性SD大鼠60只，随机分为四组，A组：对照组（sham组）；B组：切除卵巢组；C组：切除卵巢＋雌激素治疗组；D组：切除卵巢＋降钙素治疗组。除A组外，其他三组通过切除双侧卵巢法12周后制成骨质疏松模型，24周后分别行k的力学特性、右侧股骨三点弯曲试验、羟脯氨酸含量、k骨密度（BMD）测定，Masson三色染色法显示骨胶原形态。结果A、C、D组与B组在k羟脯氨酸含量、BMD、k压缩力学参数值、右侧股骨生物力学参数值、骨胶原染色含量及形态方面差异均有统计学意义（P〈0．05），而A、C、D组之间差异无统计学意义（P〉0．05）。统计学分析显示羟脯氨酸含量与BMD及骨生物力学参数值呈直线相关性。结论骨质疏松的发生与骨胶原含量下降有关。骨胶原含量的下降与BMD降低及骨生物力学改变呈相关性。应用雌激素和降钙素治疗去势后骨质疏松大鼠，不仅可以提高其BMD含量和骨生物力学性能，而且还可以提高骨胶原的含量。     

用心肌灌注显像靶心图定量分析评价AMI患者骨髓干细胞移植术疗效

目的 探讨靶心图上心肌灌注缺损区定量分析方法的可靠性、重复性及应用价值。方法 16例急性心肌梗死（AMI）行自体骨髓单个核细胞移植治疗的住院患者，于治疗前、治疗后45和90d行^99Tc^m-MIBI静息心肌灌注显像。在靶心图上勾画缺损区（在左心室靶心图中放射性计数低于40％的区域），并进行定量分析。结果 （1）不同操作者所得ROI结果之间的差异无统计学意义（t=0．52，P〉0．05）。（2）治疗后45d心肌灌注缺损区面积较治疗前缩小34．32％，差异有统计学意义（t=2．83，P〈0．05）；治疗后90d心肌灌注缺损区面积较治疗后45d缩小14．77％，差异有统计学意义（t=2．51，P〈0．05）。示自体骨髓单个核细胞移植对缺血心肌的恢复有一定疗效，能够缩小梗死面积，且自体骨髓单个核细胞冠状动脉内移植治疗AMI的疗效在移植后早期（45d内）即有体现。（3）面积百分比是观察心肌灌注变化的重要定量指标。结论 该方法对心肌病变范围及严重程度能准确定量；对评价AMI骨髓于细胞移植术疗效有一定的价值。