锶磷灰石体外细胞毒性研究

目的 评价锶磷灰石的细胞毒性。方法 用增殖度法，MTT比色法，流式细胞仪法评价锶磷灰石的细胞毒性，锶磷灰石掺锶量分别为0％，1％，5％，10％，100％。结果 所有不同掺锶量锶磷灰石均无明显细胞毒性表现，但掺锶量的增加细胞毒性有逐渐明显的趋势。流式细胞检测表明，1％，5％锶磷灰石的细胞毒性与纯羟磷灰石无明显差异。结论 锶磷灰石具有良好的细胞亲和性；掺锶量为10％，100％的锶磷灰石具有弱细胞毒性。     

雷耐酸锶预防大鼠糖皮质激素性骨质疏松的实验研究

目的研究雷耐酸锶对地塞米松诱发的继发性骨质疏松的预防作用。方法将80只SPF级sD大鼠,随机分为4组,正常组：常规喂饲;模型组：常规喂饲60天,第61天开始予地塞米松1mg／（kg·d）,90d;预防I组：连续60天给予雷耐酸锶75mr／（kg·d）,第61天开始,给予雷耐酸锶75mg／（kg·d）和地塞米松1mg／（kg·d）,持续90d;预防Ⅱ组：常规喂饲60天,从第61天开始,给予1mg／（kg·d）地塞米松和75ms／（kg·d）的雷耐酸锶,持续90天。实验结束,取股骨和第五腰椎进行骨密度检测,股骨进行骨形态计量学检测。结果预防组骨小梁面积百分数、骨小梁厚度及骨,卜梁数目均有改善,股骨周长百分数、骨形成率、成骨细胞数均提高,而破骨细胞数下降。预防I组破骨细胞数少于预防Ⅱ组,而且预防I组成骨细胞数高于预防Ⅱ组,两组间差异有统计学意义（P〈0．05）。结论动物实验证明,雷耐酸锶对地塞米松诱发的糖皮质激素性骨质疏松有预防作用。     

90Sr-90Y敷贴联合普萘洛尔治疗婴幼儿大面积皮肤血管瘤的临床观察

目的 探讨90Sr-90Y敷贴联合普萘洛尔治疗婴幼儿大面积皮肤血管瘤的临床疗效.方法 将39例婴幼儿大面积皮肤血管瘤患儿按随机数字表法分为2组,进行前瞻性研究:观察组18例,采用90Sr-90Y敷贴治疗同时给予普萘洛尔口服;对照组21例,单纯采用90Sr-90Y敷贴治疗.对比观察2组患儿疗效,并对相关数据行秩和检验及x2检验.结果 观察组治愈率为44.4％ (8/18),好转率为55.6％ (10/18),有效率为100.0％ (18/18),加重率为0(0/18);对照组治愈率为14.3％ (3/21),好转率为52.4％(11/21),有效率为66.7％(14/21),加重率为19.0％ (4/21).观察组疗效优于对照组(Z=-2.861,P＜0.05);观察组1周内见效率为72.2％(13/18),高于对照组(14.3％,3/21;x2=13.447,P＜O.05);观察组不良反应发生率为66.7％(12/18),高于对照组(19.0％,4/21;x2=9.084,P＜0.05).结论 普萘洛尔联合90Sr-90Y治疗婴幼儿大面积皮肤血管瘤具有较好的临床疗效,但必须密切监测不良反应的发生.     

Addition of metal chlorides to a HOCl conditioner can enhance bond strength to smear layer deproteinized dentin

ObjectivesTo evaluate the effect of smear layer deproteinization using hypochlorous acid (HOCl) with/without metal chlorides (SrCl₂ and ZnCl₂) on the microtensile bond strength (µTBS) of two simplified adhesives to dentin.MethodsHuman dentin surfaces with a standardized smear layer were pretreated using a 105 ppm HOCl solution with/without SrCl₂ (0.05 M, 0.1 M, 0.2 M, 0.4 M) or ZnCl₂ (0.05 M, 0.1 M, 0.2 M) for 5 s, 15 s, or 30 s. After the deproteinizing solution was washed out with water for 5 s, 15 s, or 30 s, pretreated surfaces were bonded with one-step self-etch adhesive Bond Force II or universal adhesive Clearfil Universal Bond Quick, and µTBS was measured after 24 h. Additionally, the deproteinizing effects of HOCl solutions with/without the metal chlorides were compared by measuring changes in the amide:phosphate ratio using attenuated total reflection Fourier transform infrared spectroscopy. Statistical analysis was performed using multifactor ANOVA, Tukey’s post hoc tests and t-tests (p < 0.05).ResultsPretreatment with pure HOCl for 15 s and 30 s significantly decreased the amide:phosphate ratio (p < 0.05), indicating effective deproteinization, but the µTBS of both adhesives increased significantly only if HOCl was washed out for 30 s (p < 0.05). Increasing the concentrations of metal chlorides enabled shortening of the wash-out time down to 5 s while maintaining the improved µTBS (p < 0.05). The deproteinizing effect of HOCl was not significantly altered by the addition of metal chlorides (p > 0.05).SignificanceThe effectiveness of smear layer deproteinization using HOCl can be improved by the addition of metal chlorides, as their increasing concentration allowed to shorten the wash-out time from 30 s down to 5 s     

Osteoprotegerin deficiency attenuates strontium‐mediated inhibition of osteoclastogenesis and bone resorption

Strontium (Sr) exerts an anabolic and antiresorptive effect on bone, but the mechanism remains unknown. Osteoprotegerin (OPG) expressed by osteoblasts plays an important role in regulating bone homeostasis by inhibiting osteoclastogenesis and bone resorption. This study aims at evaluating the role of OPG in Sr‐mediated inhibition of osteoclastogenesis and bone resorption. Six‐week‐old Opg knockout (KO) male mice and their wild‐type (WT) littermates were treated orally with vehicle (Veh) or Sr compound (4 mmol/kg) daily for 8 weeks. Bone mass and microstructure in the lumbar spine (L₄) and proximal tibia were analyzed with micro–computed tomography (µCT). Bone remodeling was evaluated with serum biochemical analysis and static and dynamic bone histomorphometry. Osteoclast differentiation potential and gene expression were analyzed in bone marrow cells. The findings demonstrate that Sr compound treatment results in greater bone volume and trabecular number than Veh treatment in WT mice. The anabolic response of trabecular bone to Sr treatment is attenuated in KO mice. Although Sr treatment significantly decreases in vitro osteoclastogenesis and bone resorption in WT mice, these effects are attenuated in KO mice. Furthermore, Sr treatment profoundly increases Opg gene expression in the tibias and OPG protein levels in the sera of WT mice. This study concludes that the inhibition of osteoclastogenesis and bone resorption is possibly associated with OPG upregulation by Sr treatment. © 2011 American Society for Bone and Mineral Research.     

Long-term treatment of osteoporosis in postmenopausal women: a review from the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) and the International Osteoporosis Foundation (IOF)

Abstract

Introduction:

Postmenopausal osteoporosis is a chronic disease requiring treatment that balances long-term fracture efficacy against risk.     

雷奈酸锶对大鼠应力缺失性骨丢失的防治作用

摘要： 目的 探讨雷奈酸锶对尾悬吊导致的应力缺失性大鼠骨质疏松的防治效果。方法 6 月龄 SD 大鼠 30 只, 随机均分为 3 组： 正常对照组（A 组）、 尾悬吊组（B 组）、 雷奈酸锶干预组（C 组）。B、 C 两组大鼠采用尾悬吊法制 备应力缺失型骨质疏松大鼠模型, C 组给予 1 g/(kg·d） 雷奈酸锶干预, 4 周后处死所有大鼠, 取左侧股骨检测骨密度, 取左侧胫骨制备非脱钙组织切片并行骨形态计量学检测, 取右侧股骨和胫骨骨髓细胞体外培养并向成骨细胞诱导 分化, 取第 4 代细胞及血清检测骨钙素 （OCN） 的表达。结果 B 组骨密度低于 A 组, C 组高于 B 组 （P＜0.05）。 B 组 骨小梁体积（BV/TV）、 骨小梁数量（Tb.N）、 骨小梁厚度（Tb.Th）低于 A、 C 组, 破骨细胞数（Oc.N）、 骨吸收长度比（Er. Pm）高于 A 组, C 组骨形成率（BFR/BV）、 矿化长度比（L.Pm）高于 B 组, Er.Pm、 Oc.N 低于 B 组（P＜0.05）。B、 C 组 OCN mRNA 表达水平高于 A 组, 但血清中 OCN 水平 B 组低于 A、 C 组 （P＜0.05）。结论 尾悬吊 4 周可造成大鼠骨 丢失, 雷奈酸锶可抑制其骨量丢失, 作用机制可能与其通过上调 OCN 的表达促进骨形成有关。     

Effect of strontium in combination with fluoride on enamel remineralization in vitro

Previous studies showed that strontium (Sr) as well as fluoride (F) can enhance enamel remineralisation. The aim of this study was to evaluate the effects of Sr in combination with F on enamel remineralisation in vitro. Sixty enamel specimens obtained from caries free human premolars were demineralised to produce caries-like lesions. Half of each lesion was covered with nail varnish as an untreated control. The specimens were then randomly divided into F and Sr + F treatment groups. The F group was exposed to remineralising solutions (1.5 mM CaCl₂, 0.9 mM KH₂PO₄) containing 1 ppm, 0.1 ppm or 0.05 ppm F. The Sr + F treatment group was exposed to the same solutions including 10 ppm Sr. After 2 weeks, lesion depth, mineral loss and percentage enamel remineralisation were determined using transversal microradiography. There was a significant decrease in mineral loss in all groups (p < 0.001). Lesion depth was significantly reduced for all groups (p < 0.05) with the exception of group F. Remineralisation was significantly affected by F concentration (p = 0.000). The participation of Sr resulted in a significant enhancement of remineralisation (p < 0.001) with a synergistic effect of the Sr + F combination (p < 0.01). It was concluded that while the remineralising process was affected by the concentration of F, there was also an interaction between F and Sr when they were used in conjunction.     

Combined effect of strontium and pyrophosphate on the properties of brushite cements

In this study we report the synthesis of strontium-containing brushite cement with good cohesion and a diametral tensile strength (DTS) of 5 MPa. The cement powder, composed of β-tricalcium phosphate (β-TCP) and monocalcium phosphate, was adjusted by different concentrations of strontium and pyrophosphate ions. The cement liquid phase was 2 M phosphoric acid solution. The cement cohesion and mechanical properties were measured after being aged in water for 24 h at 37 °C. It was found that at low concentration both strontium and pyrophosphate ions inhibit the cement setting reaction. However, the final setting time was significantly reduced when SrCl₂ increased from 5 to 10 wt.% at pyrophosphate concentrations equal to or higher than 2.16 wt.%. The incorporation of strontium ions did not increase the DTS of brushite cements significantly. In contrast, the addition of pyrophosphate ions did increase the DTS of brushite cements significantly. When both ions were added simultaneously, the brushite cement with a Sr²⁺ content of 5 wt.% had the highest DTS value. Nevertheless, the DTS values of Sr-containing cements were significantly reduced if the pyrophosphate concentration was higher than 2.16 wt.%. The Sr²⁺ ions had a negative effect on brushite cement cohesion, although the solid weight loss started to decrease at Sr²⁺ concentrations higher than 5 wt.%.     

^90Sr-^90Y敷贴与联合瘢痕内切除术治疗大面积病理性瘢痕的疗效

目的观察对比单纯^90Sr-^90Y敷贴和瘢痕内切除术后^90Sr-^90Y敷贴治疗大面积病理性瘢痕的疗效。方法选取临床确诊的大面积病理性瘢痕患者158例,共196块病理性瘢痕,按瘢痕厚度分为A、B、C 3组,每组患者再采用简单随机法分为两部分,分别接受单纯^90Sr-^90Y敷贴治疗（102块）和瘢痕内切除术并^90Sr-^90Y敷贴治疗（94块）,治疗结束后2年评价疗效,行Ridit分析。结果瘢痕内切除术并^90Sr-^90Y敷贴的疗效明显优于单纯^90Sr-^90Y敷贴治疗（R=0．428和0．578,F=92．6,P〈0．01）,前者疗效不受瘢痕厚度的影响,后者疗效则明显受瘢痕厚度影响。结论对于瘢痕表面积和厚度较大的病理性瘢痕患者。宜采用瘢痕内切除术并^90Sr-^90Y敷贴治疗。