Morphomechanics of the humero-ulnar joint: II. Concave incongruity determines the distribution of load and subchondral mineralization

Background: A deeper joint socket (concave incongruity) is found at most angles of flexion of the humero-ulnar joint and maintained over a wide range of physiological loading. It is, however, unclear how far this incongruity affects the distribution of load and subchondral mineralization of this joint as compared with a congruous configuration. Methods: Two nonlinear, axisymmetrical finite element models with two cartilage layers were constructed, one congruous and one incongruous, with a joint space of realistic magnitude. The distribution of subchondral mineralization was determined by computed tomography osteoabsorptiometry in the same six specimens that were investigated in the first part of the study, and compared with the biomechanical data obtained there and the predictions of the models. Results: In the congruous case, the center of the socket is highly loaded, whereas the periphery does not experience mechanical stimulation. A central bone density maximum is predicted. With concave incongruity the position of the contact areas shifts from the joint margin towards the center as the load increases, and the peak stresses are considerably lower. A bicentric ventro-dorsal distribution pattern of subchondral mineralization is predicted, and this is actually found in the six specimens. Conclusions: Concave incongruity is shown to determine load transmission and subchondral mineralization of the humero-ulnar joint. It is suggested that this shape leads to a more even distribution of stress, provides intermittent stimulation of the cartilaginous tissue, and has beneficial effects on the metabolism, nutrition, and lubrication of the articular cartilage during cyclic loading. © 1995 Wiley-Liss, Inc.     

Histochemical demonstration of endogenous estrogen in breast carcinomas: Biochemical and clinical correlation

Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983.     

维生素D缺乏性晚发性佝偻病的骨密度研究

目的：探讨维生素D缺乏性晚发性佝偻病的骨密度变化;方法：采用病例对照研究方法。对640名学生进行问诊及体验,测定非优势侧尺挠骨中1／3交界处骨密度（BMD）,病例组检测骨碱性磷酸酶,拍摄腕部X光片,病例组与对照组同测血250HD3;结果：病例组骨密度显著低于对照组,病例组250HD3异常者显著低于对照组;结论：晚佝病是由于维生素D缺乏所至的骨量减少性疾病,日后影响峰值骨量的形成,并与成人期骨质疏松有密切的关系,骨密度检查对晚佝病有重要诊断价值。     

Site of bone density measurement may affect therapy decision

Summary The purpose of this study was to determine whether bone mineral density (BMD) measurements at the lumbar spine and femoral neck provided comparable information to women planning to use that knowledge to help them make a decision about hormone replacement therapy. Eighty-eight healthy Caucasian women, aged 44–59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lumbar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiometry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as at risk for osteoporosis, bone density more than one standard deviation (SD) below the young adult mean, or as low risk, bone density at or above this level. The re that 46 women would be classified into the low risk category on the basis of spinal BMD alone. However, 28 of these 46 women would fall into the at risk category when the femoral neck BMD was measured. Sixty-one percent of women informed they were at low risk on the basis of spinal BMD would be considered at risk based on femoral neck BMD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD were added. These results suggest that both lumbar spine and proximal femur measurements should be made when women are using bone density measurements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years.     

直接法与统计法测试松质骨孔隙率的比较研究

目的 探讨松质骨孔隙率的测试方法。方法 对15根猪胫骨分别采用“直接法”与“统计法”测试松质骨孔隙率或其表观密度和材料密度。结果 （1）孔隙率与表观密度呈非常显著负相关,而与材料密度相关不显著;（2）孔隙率沿轴向靠近密质量骨逐渐减小,而沿横向基本不变;（3）统计法可测出松质骨各个层面的孔隙率大小。结论 直接法和统计法均能检测松质骨孔隙率,但统计法较直接法更能反映孔隙率的分布与变化规律。     

磷脂对HDL3介导大鼠皮肤成纤维细胞内胆固醇流出能力的影响

目的　研讨磷脂对HDL3 介导大鼠皮肤成纤维细胞内胆固醇流出能力的影响。方法　在卵磷脂 (PC)或鞘磷脂 (SPM )存在条件下 ,观察HDL3 介导细胞胆固醇流出量的变化、细胞内磷脂含量变化及游离胆固醇 /胆固醇酯平衡的变化。结果　①BSA组 (对照组 )、HDL3 组、PC组、SPM组、PC HDL3 组和SPM HDL3 组分别介导 4.70 %、31.5 5 %、7.35 %、8.0 6 %、42 .95 %和 46 .98%细胞胆固醇流出 ;②BSA、HDL3 、HDL3 SPM和HDL3 PC组细胞培育后胞内卵磷脂磷含量 (PC p)和鞘磷脂磷含量 (SPM p)分别为 2 0 .0 2、5 .5 6 ,17.5 6、5 .2 8,18.6 2、7.0 0和 2 2 .5 0、5 .5 2 μg/皿 ;③PC和SPM与细胞培育后 ,胞内游离胆固醇 /总胆固醇比值分别为 49.6 5和 5 9.5 7。培育前此比值为 48.6 4。结论　①PC和SPM本身无介导细胞胆固醇流出能力 ,但它们能显著提高HDL3 介导的细胞胆固醇流出能力 ,且后者强于前者 ;②随着细胞胆固醇流出 ,部分胞内PC也流出胞外 ,而胞内SPM无明显变化 ;③SPM促进细胞内胆固醇酯向游离胆固醇转化。     

喉癌微血管生成中P53 nm23蛋白和血管内皮生长因子的作用

目的　探讨P5 3、nm2 3蛋白和血管内皮生长因子 (vascularendothelialgrowthfacor,VEGF)在喉癌微血管生成及转移中的作用。方法　通过免疫组化SP法对 42例喉癌标本中P5 3、nm2 3蛋白、VEGF及微血管密度 (microvesseldensity,MVD)进行了检测。结果　喉癌中P5 3、nm2 3蛋白及VEGF的阳性表达率分别占 47 6 %、5 7 1%和 71 4%。P5 3基因和VEGF呈正相关 (P <0 0 5 ) ,在有淋巴结转移的喉癌标本中P5 3、VEGF阳性表达率及MVD明显高于非转移组 (P <0 0 5 )。而nm2 3基因和VEGF在喉癌标本中无直接相关性 ,在nm2 3蛋白表达阴性和VEGF阳性标本中MVD较高 ,这种现象多见于有淋巴结转移的喉癌中。结论　突变型P5 3基因通过调控VEGF的表达影响肿瘤内MVD ,促使喉癌发生转移 ;而nm2 3基因可能不是通过调控VEGF的表达 ,而是通过其它途径影响喉癌转移。     

贵阳地区1?055例骨密度检测分析

采用日本阿洛卡公司双能量骨密测量仪,选择受检者桡骨远端１／３处为测量点,对贵阳地区１０５５例人群成人桡骨的骨密度进行测量,取得不同性别各年龄段的骨密度值,同时计算出贵阳地区成人桡骨各年龄段的骨密度均值及标准偏差。     

Characteristics of bone mineral density and soft tissue composition of obese Japanese women: Application of dual-energy X-ray absorptiometry

We studied the characteristics of bone mineral density (BMD) and soft tissue composition in obese Japanese women using dual-energy X-ray absorptiometry. Eighty-nine women, aged 45–85 years, were divided into three groups according to their body mass index (BMI): a thin group (n = 38; BMI < 21), a standard weight group (n = 31; BMI, 21–25), and an obese group (n = 20; BMI ≥ 25). The mean BMD of the second to fourth lumbar vertebrae and BMD of the lumbar spine, thoracic spine, pelvis, legs, and ribs of the thin group were significantly lower than those of the standard weight group or the obese group (P < 0.05), whereas no significant difference in total body BMD was observed among the three groups. There was a significant difference in total and regional fat mass among the three groups (P < 0.05). Lean mass of legs and total lean mass showed a significant difference between the thin group and the obese group (P < 0.05). The results showed that obesity was associated with higher BMD of weight bearing-bones and ribs, high total and regional fat mass, and high lean mass of bilateral legs and total lean mass. We suggest that obesity may contribute to the prevention of bone loss of weight-bearing bones and ribs and muscular atrophy of the legs. Received: Sept. 30, 1998 / Accepted: Dec. 10, 1998     

The Extent of the Dendritic Tree and the Number of Synapses in the Frog Motoneuron

Frog motoneurons were intracellularly labelled with cobaltic lysine in the brachial and the lumbar segments of the spinal cord, and the material was processed for light microscopy in serial sections. With the aid of the neuron reconstruction system NEUTRACE, the dendritic tree of neurons was reconstructed and the length and surface area of dendrites measured. The surface of somata was determined with the prolate - oblate average ellipsoid calculation. Corrections were made for shrinkage and for optical distortion. The mean surface area of somata was 6710 microm2; lumbar motoneurons were slightly larger than brachial motoneurons. The mean length of the combined dendritic tree of brachial neurons was 29 408 microm and that of lumbar neurons 46 806 microm. The mean surface area was 127 335 microm2 in brachial neurons, and 168 063 microm2 in lumbar neurons. The soma - dendrite surface area ratio was 3 - 5% in most cases. Dendrites with a diameter of 600 microm from the soma. This suggests that about two-thirds of the synapses impinged upon distant dendrites >600 microm from the soma. The efficacy of synapses at these large distances is investigated on model neurons in the accompanying paper (Wolf et al., Eur. J. Neurosci., 4 1013 - 1021, 1992).