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Paget's disease has been ascribed several times to specimens of archeological bone but, in the absence of microscopic examination, the evidence remains insubstantial. Suspected metabolic bone disease is described here in the archeological remains of a skeleton from a 16th century burial ground at Wells Cathedral, England and from a single medieval sacrum recovered from a large deposit of disarticulated bones from a churchyard at Barton-on-Humber, England. Radiographs showed apparent structural abnormality in one femoral shaft and calcaneus and in the isolated sacrum. Histomorphometry on undecalcified bone cores confirmed the regions of abnormality and showed not only increased trabecular width but also areas of "mosaic" woven bone together with extensive resorption cavities; these features contrasted with the normal structure and organized lamellar bone from sites elsewhere. Despite post-interment changes in surrounding tissues, the morphological stability of some of the osteocytes was remarkable. Preservation of the histology was sufficient to permit the assignment of a metabolic bone disorder and the nature of the sclerosis was consistent with Paget's disease.  相似文献   
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Recent studies have demonstrated homology between bone-derived growth factor and beta 2 microglobulin. We have shown that beta 2 microglobulin has proliferative actions on human bone-derived cells in vitro and that these cells also show immunogenicity for beta 2 microglobulin. beta 2 microglobulin stimulated the incorporation of 3H-thymidine into DNA of human bone cells in a dose-dependent manner. In contrast to this stimulatory action, beta 2 microglobulin had no detectable activity with the same concentration on the production of osteocalcin, alkaline phosphatase activity or prostaglandin E2 synthesis. The possibility that the human bone-derived cells could also produce beta 2 microglobulin was examined. Under basal conditions these cells exhibit immunoreactivity for beta 2 microglobulin, the expression of which could be enhanced following treatment with interferon gamma in a dose-dependent manner. The co-localization of staining for beta 2 microglobulin and alkaline phosphatase, a marker of the osteoblast phenotype, indicate that human osteoblast-like cells represent a source of activity of this factor. The production of beta 2 microglobulin by human osteoblast-like cells and the subsequent action of this factor on cells within the bone microenvironment may indicate a role for beta 2 microglobulin as a local regulator of bone metabolism.  相似文献   
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Uganda has a large population of goats, predominantly from indigenous breeds reared in diverse production systems, whose existence is threatened by crossbreeding with exotic Boer goats. Knowledge about the genetic characteristics and relationships among these Ugandan goat breeds and the potential admixture with Boer goats is still limited. Using a medium‐density single nucleotide polymorphism (SNP) panel, we assessed the genetic diversity, population structure and admixture in six goat breeds in Uganda: Boer, Karamojong, Kigezi, Mubende, Small East African and Sebei. All the animals had genotypes for about 46 105 SNPs after quality control. We found high proportions of polymorphic SNPs ranging from 0.885 (Kigezi) to 0.928 (Sebei). The overall mean observed (HO) and expected (HE) heterozygosity across breeds was 0.355 ± 0.147 and 0.384 ± 0.143 respectively. Principal components, genetic distances and admixture analyses revealed weak population sub‐structuring among the breeds. Principal components separated Kigezi and weakly Small East African from other indigenous goats. Sebei and Karamojong were tightly entangled together, whereas Mubende occupied a more central position with high admixture from all other local breeds. The Boer breed showed a unique cluster from the Ugandan indigenous goat breeds. The results reflect common ancestry but also some level of geographical differentiation. admixture and f4 statistics revealed gene flow from Boer and varying levels of genetic admixture among the breeds. Generally, moderate to high levels of genetic variability were observed. Our findings provide useful insights into maintaining genetic diversity and designing appropriate breeding programs to exploit within‐breed diversity and heterozygote advantage in crossbreeding schemes.  相似文献   
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Clodronate disodium (dichloromethylene diphosphonate), a specific inhibitor of bone resorption, was given by mouth (1.0-3.2 g daily) to nine patients with primary hyperparathyroidism for two to 32 weeks so that its clinical and metabolic effects could be evaluated. Bone resorption decreased in all patients as judged by a fall in the fasting urinary calcium to creatinine and hydroxyproline to creatinine ratios. Serum calcium concentration was increased in all patients before treatment and fell in response to treatment to values near the upper end of the normal range. Hypercalcaemia and hypercalciuria recurred when treatment was stopped. In three patients treated for longer than 19 weeks clodronate failed to sustain the reduction in serum calcium concentration but the concentration remained below pretreatment values. These results suggest that clodronate may be of use in the medical management of primary hyperparathyroidism, particularly in patients in whom suppression of bone disease is desirable before surgery or in whom surgery is contraindicated.  相似文献   
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OBJECTIVE--To determine whether alfacalcidol--used in management of overt renal bone disease--may safely prevent renal bone disease when used earlier in course of renal failure. DESIGN--Double blind, prospective, randomised, placebo controlled study. SETTING--17 nephrology centres from Belgium, France, the Netherlands, and the United Kingdom. SUBJECTS--176 patients aged 18-81 with mild to moderate chronic renal failure (creatinine clearance 15-50 ml/min) and with no clinical, biochemical, or radiographic evidence of bone disease. INTERVENTIONS--Alfacalcidol 0.25 micrograms (titrated according to serum calcium concentration) or placebo given for two years. MAIN OUTCOME MEASURES--Quantitative histology of bone to assess efficacy of treatment and renal function to assess safety. RESULTS--132 patients had histological evidence of bone disease at start of study. Biochemical, radiographic, and histological indices of bone metabolism were similar for the 89 patients given alfacalcidol and the 87 controls given placebo. After treatment, mean serum alkaline phosphatase activity and intact parathyroid hormone concentration had increased by 13% and 126% respectively in controls but had not changed in patients given alfacalcidol (P < 0.001). Hypercalcaemic episodes occurred in 10 patients given alfacalcidol (but responded to decreases in drug dose) and in three controls. Histological indices of bone turnover significantly improved in patients given alfacalcidol and significantly deteriorated in controls: among patients with abnormal bone histology before treatment, bone disease resolved in 23 (42%) of those given alfacalcidol compared with two (4%) of the controls (P < 0.001). There was no difference in rate of progression of renal failure between the two groups. CONCLUSION--Early administration of alfacalcidol can safely and beneficially alter the natural course of renal bone disease in patients with mild to moderate renal failure.  相似文献   
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