Determination of the bioavailability of intranasal elcatonin in humans: Development of a sandwich transfer enzyme immunoassay for elcatonin

A sandwich transfer enzyme immunoassay for elcatonin (ECT) and its usability for the pharmacokinetic study are described. The anti-salmon calcitonin (SCT) antibody was used for the present assay. The assay procedure consisted of the reaction of ECT with 2,4-dinitrophenylbiotinyl anti-SCT IgG and anti-SCT Fab′-β-D -galactosidase conjugate, trapping onto (anti-2,4-dinitrophenyl bovine serum albumin) IgG-coated polystyrene balls, eluting with ϵN-2,4-dinitrophenyl-L-lysine and transferring to streptavidin-coated polystyrene balls and fluorometric detection of β-D -galactosidase activity. The practical detection limit of ECT was 0.15 pg (44 amol)/50 μl of sample and 3 pg/ml as the concentration. The application of this method has enabled us to directly estimate the bioavailability of ECT dosed intranasaly at a therapeutic level (100 IU, 17 μg) for its anti-osteoporotic effect as compared to an intramuscular dose (40 IU, 6.7 μg). The pharmacokinetic parameters of the intranasal ECT (n = 6) thus estimated were as follows: the area under the serum concentration-time curve (AUC) = 2,570 ± 1,650 (SD) pg × min/ml, and the maximal concentration (Cmax) = 60 ± 25 (SD) pg/ml with the maximal time (Tmax) = 17.5 ± 6.9 (SD) min, when the AUC for the intramuscular ECT (n = 9) = 9,460 ± 5,870 (SD) pg × min/ml and the Cmax = 165 ± 79 (SD) pg/ml with the Tmax = 16.1 ± 4.2 (SD) min. J. Clin. Lab. Anal. 12:356–362, 1998. © 1998 Wiley-Liss, Inc.     

磷酸盐尿性间叶肿瘤误诊分析(附7例)

目的:分析磷酸盐尿性间叶肿瘤(PMT)误诊原因,明确影像学检查路径。方法:回顾性分析我院2017年7月至2022年3月经病理证实PMT患者临床、影像、病理资料。结合文献复习,总结误诊原因,提出影像学检查路径。结果:7例患者3例男性,4例女性,平均年龄为(50.29±15.66)岁(范围17～69岁)。患者表现为不同程度乏力、骨痛等,均伴随骨折,病程平均(5.00±3.25)年(范围1～12年)。患者术前血磷均减低,术后血磷均升高,6例患者血磷在术后7～15天恢复正常,1例失访。6例患者术前碱性磷酸酶升高,1例正常。肿瘤最大径(2.01±1.32)cm(范围0.8～2.5 cm),2例位于软组织,5例位于骨组织。6例行X线检查,显示全身或局部骨质不同程度骨软化和伴随骨折,3例病灶无法显示。6例CT检查中5例骨组织病灶显示为高密度,1例为软组织密度结节。6例MRI平扫T1WI为低、等信号为主,偶尔见高信号,T2WI混杂高信号,内部或边缘可见低信号区。4例MRI增强检查显示病灶中度至明显强化,强化不均匀。结论:PMT影像表现缺乏特异性,容易被误诊。骨质软化、骨痛、骨折以及低血磷、高碱性磷酸酶...     

散发性低磷血性骨软化症临床及影像学表现

目的 观察散发性低磷血性骨软化症(HO)的临床及影像学表现。方法 回顾性分析19例散发性HO患者，观察其临床及影像学表现。结果 19例散发性HO患者首发症状均为不同程度骨痛及肌无力；19例均见低磷血症，9例血钙降低，16例碱性磷酸酶(ALP)升高，4例甲状旁腺激素(PTH)升高，7例24 h尿钙(UCa)升高、2例降低，18例24 h尿磷(UP)降低、1例升高。X线片示11例骨质疏松、6例退变、6例骨折；全身骨扫描示18例全身多发局部骨代谢活跃灶；骨密度双能X线吸收测定法扫描(DEXA)示16例患侧髋关节骨质疏松、3例骨量减少，8例脊柱区域骨质疏松、11例骨量减少；MRI示11例双侧股骨头关节面下条形T1低信号，脂肪抑制序列呈高信号；8例胸腰椎体上、终板下条片状双低信号，脂肪抑制序列见周围骨质片状稍高信号，呈“夹心板”征。结论 散发性HO以全身多部位不同程度骨痛和肌无力为主要临床表现，伴低血磷、低UP及高ALP等；影像学可见骨质密度异常、横向假骨折线、软骨下细微骨折及“夹心板”征等改变。     

Tumor induced osteomalacia from a peripheral mesenchymal tumour of the foot

Tumour induced osteomalacia (TIO) is a rare condition caused by peripheral mesenchymal tumours (PMT) which produce fibroblast-growth factor 23 (FGF23). FGF23 inhibits renal phosphate reabsorption leading to vitamin D resistant osteomalacia. The rarity of the condition and difficulty with isolating the PMT make diagnosis difficult, with delayed treatment leading to significant patient morbidity. We present a case of PMT of the foot with TIO, with a discussion on diagnosis and treatment.