儿童1型糖尿病骨密度变化及影响因素分析

目的 测定儿童1型糖尿病(T1DM)患者骨密度(BMD),分析探讨骨密度变化的影响因素。方法 选取于2018年1月—2021年6月于我院收治的儿童1型糖尿病患者76例,收集性别、年龄、发病年龄、身高、体重、BMI、病程等基本资料,检测空腹血糖、空腹C肽、糖化血红蛋白(HbA1c)、血碳酸氢根(HCO3-)、血清碱性磷酸酶(ALP),应用双能X线吸收测定法测定骨密度,获取Z值。结果 76例儿童1型糖尿病患者骨密度Z值为-0.93±2.14。HbA1c、病程与骨密度Z值呈负相关,差异具有统计学意义(分别B=-0.334,P<0.001;B=-0.191,P=0.017)。结论 儿童1型糖尿病患者骨密度低于健康儿童,血糖控制不良、病程长是1型糖尿病儿童骨密度减低的危险因素。     

材料和孔隙率对可降解支架内骨形成的影响

目的研究可降解支架植入人体后的骨修复,不同材料和孔隙率对支架内骨形成的影响。方法根据骨折愈合自然反应机理,运用有限元方法,结合支架几何结构,搭建以材料降解曲线和骨重建控制方程为基础的计算耦合模型。通过这一平台,选择5种材料、4种孔隙率的支架代表性体积元进行计算模拟分析,并通过骨密度和支架最大应力反映这一动态过程。结果材料弹性模量对支架内骨组织生长的影响较大,材料弹性模量越小,骨形成量越大,但会对支架的力学性能造成较大影响。较高孔隙率的支架刚度小,能够更好地促进骨组织形成,但同时也会破坏支架的力学稳定性。结论根据不同年龄、性别和部位骨组织的性能需求,为可降解多孔骨支架的材料和孔隙率选择、结构设计以及临床应用提供个性化参考和计算依据。     

Radiomics for classification of bone mineral loss: A machine learning study

PurposeThe purpose of this study was to develop predictive models to classify osteoporosis, osteopenia and normal patients using radiomics and machine learning approaches.Materials and methodsA total of 147 patients were included in this retrospective single-center study. There were 12 men and 135 women with a mean age of 56.88 ± 10.6 (SD) years (range: 28–87 years). For each patient, seven regions including four lumbar and three femoral including trochanteric, intertrochanteric and neck were segmented on bone mineral densitometry images and 54 texture features were extracted from the regions. The performance of four feature selection methods, including classifier attribute evaluation (CLAE), one rule attribute evaluation (ORAE), gain ratio attribute evaluation (GRAE) and principal components analysis (PRCA) along with four classification methods, including random forest (RF), random committee (RC), K-nearest neighbor (KN) and logit-boost (LB) were evaluated. Four classification categories, including osteopenia vs. normal, osteoporosis vs. normal, osteopenia vs. osteoporosis and osteoporosis + osteopenia vs. osteoporosis were examined for the defined seven regions. The classification model performances were evaluated using the area under the receiver operator characteristic curve (AUC).ResultsThe AUC values ranged from 0.50 to 0.78. The combination of methods RF + CLAE, RF + ORAE and RC + ORAE yielded highest performance (AUC = 0.78) in discriminating between osteoporosis and normal state in the trochanteric region. The combinations of RF + PRCA and LB + PRCA had the highest performance (AUC = 0.76) in discriminating between osteoporosis and normal state in the neck region.ConclusionThe machine learning radiomic approach can be considered as a new method for bone mineral deficiency disease classification using bone mineral densitometry image features.     

症状前期进行性肌营养不良患儿24例病例系列报告

背景：进行性肌营养不良（PMD）中Duchenne型肌营养不良(DMD)和Becker型肌营养不良(BMD)的临床表现、治疗和预后差异明显，目前国内外对症状前期PMD患儿的诊断尚无共识。 目的：探讨婴幼儿时期症状前期PMD患儿的临床特征和实验室检查特点，并探讨血清肌酶水平在DMD和BMD分型诊断中的价值。 设计：病例系列报告。 方法：收集2016年1月至2020年7月江西省儿童医院确诊的症状前期PMD患儿，分析临床特征和实验室检查特点，并以基因检测结果为诊断标准分为DMD组和BMD组，血清肌酶通过ROC曲线分析以约登指数最大值时的取值作为诊断界值，比较不同肌酶的诊断准确性。 主要结局指标：PMD患儿的临床表现、基因结果、血清酶水平（AST、ALT、LTH、CK、CK-MB）。 结果：24例PMD患儿纳入分析，其中DMD组18例，BMD组6例。22例（91.7%）因发现转氨酶升高就诊，2例（8.3%）因亲戚确诊前来就医。PMD患儿CK-MB、CK、LDH、AST和ALT水平均明显升高，DMD组均高于BMD组（除AST外，P均<0.05）。当ALT>224.5 U·L-1、CK>11 069 IU·L-1、CK-Mb>204 IU·L-1、LDH>1 349.5 IU·L-1时为DMD的可能性更高，尤其是LDH>1 349.5 IU·L-1具有高度特异性。 结论：血清肌酶水平增高为 PMD 患儿症状前期的主要表现。LDH＞1 349.5 IU·L-1对诊断DMD具有高度特异性。     

六味地黄丸联合唑来膦酸治疗妇女绝经后骨质疏松的临床研究

目的探讨六味地黄丸联合唑来膦酸治疗妇女绝经后骨质疏松的临床效果。方法选取2015年6月—2017年1月广东医科大学附属医院收治的86例绝经后骨质疏松患者,随机分为对照组和治疗组,每组各43例。对照组静脉滴注唑来膦酸注射液,5 mg/次,1次/年。治疗组在此基础上口服六味地黄丸,8丸/次,3次/d。所有患者均连续治疗12个月。观察两组的临床疗效,比较两组治疗前后视觉模拟(VAS)评分、简明健康状况调查量表(SF-36)评分、腰椎1~4骨质密度(BMD)、全髋关节骨BMD、左侧股骨颈BMD、Ⅰ型原胶原氨基端前肽(PINP)、β-胶原降解产物(β-CTX)、碱性磷酸酶(ALP)、骨钙素(BGP)的变化情况。结果治疗后,对照组和治疗组的总有效率分别为79.07%、95.35%,两组比较差异有统计学意义(P0.05)。治疗后,两组VAS评分、血清PINP、β-CTX、ALP及BGP水平显著降低,SF-36评分、腰椎1~4 BMD值、全髋关节骨BMD值、左侧股骨颈BMD值显著升高,同组治疗前后比较差异有统计学意义(P0.05);治疗后,治疗组VAS评分、血清PINP、β-CTX、ALP及BGP水平低于对照组,SF-36评分、腰椎1~4 BMD值、全髋关节骨BMD值、左侧股骨颈BMD值高于对照组,两组比较差异有统计学意义(P0.05)。结论六味地黄丸联合唑来膦酸治疗妇女绝经后骨质疏松具有较好的临床疗效,可有效缓解患者疼痛症状,增加骨密度,提高生活质量,具有一定的临床推广应用价值。     

辛伐他汀对正畸牙齿保持阶段骨形成的影响

目的:探讨全身给予辛伐他汀对大鼠正畸牙齿移动后保持阶段骨形成生化指标和骨密度的影响。方法:选用40只雄性Wistar大鼠,随机分成5组:基本对照组、阴性对照组(生理盐水)、低剂量组(2.5mg/kg)、中剂量组(5.0mg/kg)、高剂量组(10.0mg/kg),牵引其上颌第一磨牙向近中移动。实验组在加力装置去除前1d开始,腹膜下注射辛伐他汀;阴性对照组注射生理盐水,1次/d。4周后处死大鼠,取血,检测血清骨钙素(BGP)、碱性磷酸酶(ALP)、钙(Ca)、磷(P),测定上颌第一磨牙区牙槽骨密度(BMD)等。结果:实验组BGP、ALP水平较阴性对照组明显升高(P<0.05),低剂量组升高最明显,随剂量增加,BGP、ALP水平减低;实验组与对照组血清Ca、P无明显差别(P>0.05)。上颌第一磨牙区牙槽骨BMD对照组明显高于其它各组(P<0.05);实验组与阴性对照组比较,低剂量组最高,差异有显著性(P<0.05)。结论:辛伐他汀全身给药能够有效地促进局部牙槽骨骨合成代谢,最适有效剂量为2.5mg/kg。     

Relationship between bone mineral density and bone stiffness in bone fracture

Objectives Using cancellous bone blocks of racehorses, the relationship between bone mineral density (BMD), which indicates bone strength, and stiffness in bone fracture occurrences was studied.Methods Two groups of cancellous bone blocks were prepared: a fractured group, using the first phalangeal bones of seven racehorses with sagittal fractures; and a nonfractured group, using the first phalangeal bones of nine autopsied racehorses without any fractures. By a peripheral quantitative computed tomography scan, the BMD values were shown as color images and evaluated. In addition, the BMD values obtained from the fractured and nonfractured groups were compared with the stiffness values obtained from a compression test.Results The difference between the average BMD values of the fractured and nonfractured groups was easily observed on the BMD color-conversion display image. The average BMD of the fractured group (472.1 mg/cm³) was significantly higher than that of the nonfractured group (284.5 mg/cm³, P = 0.005). Moreover, the average stiffness of the fractured group (5564.5 N/cm) was significantly higher than that of the nonfractured group (3808.6 N/cm, P = 0.008).Conclusion These results suggest that the occurrence of a fracture does not depend on the BMD or the bone stiffness value.     

The effcct of eel bone powder on bone mineral density in mouse femoral bone

Improvement in bone mineral density (BMD) in the femur after administration of eel bone powder (EBP) was evaluated in ovariectomized (OVX) mice. Female ICR mice were given ovariectomies or sham operations at 9 weeks of age, then housed for 2 weeks during which they were allowed free access to a normal diet. Subsequently, the mice were divided into 3 groups: sham-operated mice fed a normal diet, OVX mice fed a normal diet, and OVX mice fed a diet containing EBP. After the mice in these 3 groups had been housed for 2 months (during which time they were allowed free access to their respective diets), they were dissected and analyzed. The BMD values in the removed femurs were measured by peripheral quantitative computed tomography (pQCT). Femoral total and femoral cancellous BMD values were higher in the EBP-treated group than in the nontreated group. Total BMD: the value in the EBP-treated group was 573 mg/cm³, and that in the non-treated group was 451 mg/cm³ (p<0.05). Cancellous BMD: the value in the EBP-treated group was 242 mg/cm³, and that in the non-treated group was 143 mg/cm³ (p<0.05). However, cortical BMD values did not significantly differ between the EBP-treated group and the non-treated group. Cortical BMD: The value in the EBP-treated group was 1891 mg/cm³, and that in the non-treated group was 1900 mg/cm³. pQCT was used to measure the cortical and cancellous BMD in the long bones. By use of a color conversion technique to display BMD, regional changes in the long bones can be expressed and easily measured. It has been well documented that EBP is effective for improvement or prevention of BMD reduction associated with OVX.     

Effects of Odanacatib on the Radius and Tibia of Postmenopausal Women: Improvements in Bone Geometry,Microarchitecture, and Estimated Bone Strength

The cathepsin K inhibitor odanacatib (ODN), currently in phase 3 development for postmenopausal osteoporosis, has a novel mechanism of action that reduces bone resorption while maintaining bone formation. In phase 2 studies, odanacatib increased areal bone mineral density (aBMD) at the lumbar spine and total hip progressively over 5 years. To determine the effects of ODN on cortical and trabecular bone and estimate changes in bone strength, we conducted a randomized, double‐blind, placebo‐controlled trial, using both quantitative computed tomography (QCT) and high‐resolution peripheral (HR‐p)QCT. In previously published results, odanacatib was superior to placebo with respect to increases in trabecular volumetric BMD (vBMD) and estimated compressive strength at the spine, and integral and trabecular vBMD and estimated strength at the hip. Here, we report the results of HR‐pQCT assessment. A total of 214 postmenopausal women (mean age 64.0 ± 6.8 years and baseline lumbar spine T‐score –1.81 ± 0.83) were randomized to oral ODN 50 mg or placebo, weekly for 2 years. With ODN, significant increases from baseline in total vBMD occurred at the distal radius and tibia. Treatment differences from placebo were also significant (3.84% and 2.63% for radius and tibia, respectively). At both sites, significant differences from placebo were also found in trabecular vBMD, cortical vBMD, cortical thickness, cortical area, and strength (failure load) estimated using finite element analysis of HR‐pQCT scans (treatment differences at radius and tibia = 2.64% and 2.66%). At the distal radius, odanacatib significantly improved trabecular thickness and bone volume/total volume (BV/TV) versus placebo. At a more proximal radial site, odanacatib attenuated the increase in cortical porosity found with placebo (treatment difference = –7.7%, p = 0.066). At the distal tibia, odanacatib significantly improved trabecular number, separation, and BV/TV versus placebo. Safety and tolerability were similar between treatment groups. In conclusion, odanacatib increased cortical and trabecular density, cortical thickness, aspects of trabecular microarchitecture, and estimated strength at the distal radius and distal tibia compared with placebo. © 2014 American Society for Bone and Mineral Research