Bone disease in primary biliary cirrhosis: Lack of association with distal renal tubular acidosis

Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Quantitation of T2′ anisotropic effects on magnetic resonance bone mineral density measurement

In this paper, the authors quantitate the anisotropy of susceptibility effects in an uniaxial trabecular bone model and show its relevance to clinical MR bone mineral density measurements. A physical model is described that quantitates the anisotropic MR behavior of uniaxial trabecular bone. To test the model, a phantom of parallel polyethylene filaments was scanned every 15° between 0° and 90° with respect to the system's main magnetic field (B₀). The distal radial metaphysis of a healthy female volunteer was scanned in orthogonal projections. The signal from each phantom image and each radial image was separated in a pixel-wise fashion into R₂ and R₂′ maps. As predicted, R₂′ relaxation showed anisotropic behavior and changed according to sin² (?), confirming that columnar structures parallel with B₀ will cause no MR susceptibility effects. Scans of the distal radius showed that R₂′ relaxation was twice as great with the forearm perpendicular to B₀ as when it was parallel to it, demonstrating different contributions from struts and columns. For both phantom and radial bone scans, R₂ relaxation was isotropic and did not change with object orientation.     

Osteoporosis and Back Pain among the Elderly

Questionnaire responses from 120 men and 337 women over the age of 50 years were studied to determine the prevalence of back pain among the elderly. In order to gain a rough indication of the back pain among elderly women which might be due to osteoporosis, the prevalence was compared in the two sexes. The prevalence of back pain without radiation to the legs and concomitant morbidity was found to be similar among men and women up to the 70–79-year age-group. After this age the prevalence was higher in women. Those with exceptional loss of body height or kyphosis had a high prevalence of back pain, while those who had sustained previous hip or radius fractures did not. There was increasing prevalence of back pain among women with increasing number of previous fractures. The study gives little indication of serious morbidity of osteoporosis in the form of back pain before very old age.     

The prevention or treatment of age-related osteoporosis in the elderly by systemic recombinant growth factor therapy (rhIGF-I or rhTGFβ): a perspective

Boonen S, Broos P, Dequeker J, Bouillon R (Department of Internal Medicine, Division of Geriatric Medicine, the Arthritis and Metabolic Bone Disease Research Unit, the Department of Traumatology and Emergency Surgery and the Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium). The prevention or treatment of age-related osteoporosis in the elderly by systemic recombinant growth factor therapy (rhIGF-I or rhTGFβ): a perspective (Review). J Intern Med 1997; 242 : 285–90.
Both insulin-like growth factor-I (IGF-I) and transforming growth factor β (TGFβ) have powerful modulatory effects in a variety of tissues. A major target of action is the skeletal system, where they enhance bone formation and decrease matrix degradation, thus playing a part in the maintenance of bone mass. Because of the potent mitogenic effect of these agents on osteoblasts, recombinant IGF-I (rhIGF-I) and recombinant TGFβ (rhTGFβ) have potential as drugs to stimulate bone formation in the prevention and treatment of osteoporosis. Using biochemical markers, subcutaneous rhIGF-I therapy has been shown to increase bone turnover and bone formation in nonosteoporotic older people. However, a corresponding increase in bone mass has not yet been documented nor have there been reports yet on the effects of systemically administered rhTGFβ in humans. Further investigation is required to define the clinical potential of rhIGF-I and rhTGFβ as therapeutic agents in age-related osteoporosis.     

Decreased trabecular bone mineral density in patients with phenylketonuria measured by peripheral quantitative computed tomography

The bone mineral density (BMD) of 14 children, adolescents, and adults with phenylketonuria (PKU) on dietary treatment (age 5-28 y; 6F, 8M) was investigated using peripheral quantitative computed tomography (pQCT) of the distal radius. BMD of total (TBMD) and spongy bone (SBMD) were compared to those of healthy gender-, age-, weight- and height-matched controls. We found a significant decrease of SBMD in patients with PKU while TBMD was only slightly decreased, reaching no statistical significance. These results indicate minor changes of BMD in patients with PKU under treatment, which are more accentuated in the trabecular bone compartment. One additional patient who was untreated until the pQCT investigation at the age of 10 y also showed markedly decreased SBMD and TBMD.     

低剂量激素替代治疗对绝经后妇女骨代谢的影响

目的 探讨低剂量结合型雌激素（ＣＥ）和安宫黄体酮（ＭＰＡ）联合应用对骨代谢的影响，方法３４例绝经后妇女随机分为两组，试验组１７例，ＣＥ０．６２５ｍｇ与ＭＰＡ２ｍｇ隔日口服交替应用，对照组１７例，口服ＣＤ０．６２５ｍｇ／ｄ，每月连续服用２５ｄ，后１０ｄ加用ＭＰＡ４ｍｇ。两组均连续服用４周期，于用药前后分别测定血碱性磷酸酶（ＡＬＰ）及尿Ｃａ／Ｃｒ比值。结果 实验组完成治疗者１６例，对照组完成治疗者１５     

人工股骨头置换治疗老年不稳定性股骨转子间骨折近期疗效

目的探讨人工股骨头置换术治疗老年股骨转子间不稳定性骨折的近期疗效。方法应用人工股骨头置换术治疗高龄、有明显骨质疏松的股骨转子间不稳定性骨折患者20例。结果20例获2-24个月随访,患者术后14-35d负重行走,无坠积性肺炎、尿路感染的发生。术后X线片示假体位置良好,无下沉松动,无脱位,未出现髋内翻。Harris评分为75-92分。1例行走髋关节疼痛,1例9个月时X线片发现髋臼磨损。结论该手术方法具有功能恢复好、并发症少、能早期负重等优点,有临床上推广应用的价值,但应严格掌握其适应证。     

糖疏康对糖尿病骨质疏松大鼠VDR、TGF-β1、CaBp-D9K mRNA表达影响的实验研究

目的观察糖疏康对糖尿病性骨质疏松（DOP）大鼠维生素D受体（VDR）mRNA、转移生长因子-β1（TGF-β1）mRNA、钙结合蛋白（CaBp-D9K）mRNA表达水平的影响。方法采用腹腔注射链脲佐菌素造模。Wistar大鼠50只．10只作空白对照组,余大鼠腹腔内注射链脲佐菌素造糖尿病模型,测血糖后将符合诊断标准的30只糖尿病大鼠随机分成治疗组、西药对照组与病理组。分别给予糖疏康、碳酸钙阿法迪三和生理盐水灌胃给药。12周后取材,切片,进行维生素D受体（VDR）mRNA、转移生长因子-β1（TGF-β1）mRNA、钙结合蛋白（CaBp-D9K）mRNA原位杂交实验。结果糖疏康组与碳酸钙阿法迪三对照组治疗后提高VDRmRNA、CaBp-D9KmRNA与骨TGF-β1mRNA表达水平,且两组之间有显著差异（P〈0．01）。结论糖疏康能够调节DOP大鼠小肠VDRmRNA、CaBp-D9KmRNA与骨TGF-β1mRNA表达水平,影响VDR、CaBp-D9K与TGF-β1的合成与分泌,进而促进肠钙吸收与成骨细胞活性。