The measurements of parathyroid hormones in sera of elderly osteoporotic patients with serum high alkaline phosphatase activity

This study was carried out to investigate effects of drugs treated in the elderly osteoporotic patients on measurements of carboxy terminal, mid-region and intact PTH, by using the various kinds of PTH kits. The drugs such as 1 alpha(OH)D3, calcitonin and so on, in the treatment of osteoporotic patients, was brought about no significant inter-relationships among carboxy terminal, mid-region and intact PTH in sera of the elderly osteoporotic patients with serum high alkaline phosphatase activity.     

The measurement of serum human parathyroid hormone (h-PTH53-84) and effect of exercise on calcium metabolism

This study was focussed our attention on the measurement within the upper physiological level of human serum parathyroid hormone (PTH), using kits of human PTH 53-84. This assay kit was able to detect serum PTH in sera with subtle changes of serum calcium concentrations before and after short term exercise. These serum PTH levels before and after exercise seemed to be changed within the upper physiological levels of PTH. Thus, this study suggested that the assay kit was likely to become a useful tool of the measurement of the physiological level of serum PTH in humans.     

The study in the relationship between serum calcium and serum parathyroid hormone (PTH) by employing the various kits of PTH assay

In order to evaluate the influences of serum PTH assay in the various concentrations of serum calcium, we divided into three groups which serum calcium had below 8.0 mg/dl, 8.2 mg/dl to 9.8 mg/dl and above 10.0 mg/dl at random samples and assayed PTH in serum sample, using various kits of PTH assay obtained from commercial sources. Our results suggested that the measurement of serum PTH influenced by the concentration of serum calcium and therefore, should be taken an attention of serum calcium in each sample.     

The measurement of parathyroid hormone in sera of hemodialysis patients with renal insufficiency by employing the various kinds of parathyroid hormone kits

This study focussed on elucidating difference of blood PTH levels, by employing the various kinds of PTH kits. We carried out the measurements of PTH levels in sera of the hemodialysis patients with renal insufficiency presumably inactivated PTH degradative regulation in kidney. Our results showed the remarkable significant relationships among blood PTH levels of carboxyl and mid-region PTH and intact PTH in hemodialysis patients and was deduced that the difference of PTH levels by using various kinds of PTH kits was responsible of PTH cleavage effect in the kidney.     

A thermodynamic study on the binding of magnesium with human growth hormone

The thermodynamic parameters underlying the binding of Mg²⁺ to the hydrophobic core of human growth hormone, hGH, are determined using isothermal titration calorimetry. The interaction between Mg²⁺ and hGH (35 μM) was studied at 27°C in NaCl solution. A new solvation model was used to reproduce the enthalpies of Mg²⁺-hGH interaction over the whole Mg²⁺ concentrations. The solvation parameters recovered from the new salvation model, were correlated to the structural changes of hGH due to the metal ion interaction.     

High-performance liquid chromatographic methods for the analysis of human parathyroid hormone in reference standards, parathyroid tissue and biological fluids

Reversed-phase high-performance liquid chromatography (RP-HPLC) has been used to fractionate human parathyroid hormone (hPTH) from a variety of natural sources and to compare it with synthetic hPTH and hPTH fragments. Multiple radioimmunoassay systems for amino, mid and carboxyl regions of hPTH were used to monitor various preparations of hPTH previously prepared by conventional methods and ampouled in nanogram amounts for reference standard and reagent purposes. Results confirmed that they were free of detectable cleavage products, but showed that the intact hPTH comprised three or four closely associated components. A similar pattern of heterogeneity was obtained when hPTH was extracted from stored human parathyroid adenomata by a simple rapid HPLC bulk fractionation method. Comparison with synthetic 1-84 hPTH and modification of sample handling to minimize oxidative conditions, indicate that some of these components are probably intermediate oxidation products. A number of less hydrophobic components, with carboxyl region immunoreactivities, were obtained from the individual adenoma samples, human parathyroid cyst fluid, ampouled samples of human adenoma tissue culture medium, and secondary hyperparathyroid plasma ultrafiltrate when they were fractionated by RP-HPLC. The results strongly suggest that the biological degradation of hPTH is more complex than generally believed, and that RP-HPLC offers a new dimension in its analysis.     

The diagnostic application of serum growth hormone, insulin-like growth factor (IGF), and IGF binding protein measurements.

Selected combinations of tests for growth hormone and the growth mediating peptides, insulin-like growth factors, and their binding proteins have improved the diagnostic reliability of the procedures used in the investigation of growth abnormalities (GH deficiency, GH and IGF receptor deficiencies, GH excess, diabetes, or undernutrition) and in malignancies associated with hypoglycemia.     

六偏磷酸钠对AZ31镁合金电化学行为的影响

为提高AZ31镁合金阳极的活化性能以及抑制它的腐蚀,用电化学等方法研究了在中性3.5%Na Cl体系中,六偏磷酸钠(Na6(PO3)6)对AZ31镁合金电化学行为的影响。结果表明:Na6(PO3)6能大幅度抑制AZ31镁合金的腐蚀,但极化程度有所增大。当Na6(PO3)6的质量分数为2.0%时,AZ31镁合金的缓蚀率高达74.9%,腐蚀后其表面均匀,且活化性能有所改善,在-1.10V处时合金的电流密度高达0.033 m A.cm-2,开路电位Eocp负移程度最大(-1.59 V),活化电位Eact负移程度最大(-1.38 V)。试验结果为AZ31镁合金作为电极材料提供了参考。     

Fully automated potentiometric determination of ionized magnesium in blood serum

Basic observations leading to the successful application of magnesium ion-selective electrodes for the automated determination of ionized magnesium in undiluted serum are discussed. The principles of the method are described and the first numerical results are reported.     

Kinetic investigations on the basis of isothermal DSC measurements of hydrogenation and dehydrogenation of magnesium hydride

Results of kinetic investigations on the basis of isothermal DSC measurements by means of defined pressure changes are presented and interpreted for the Mg/MgH₂ system. From an evaluation of the experimentally obtained DSC-signals, the dependence of reaction rate on hydrogen pressure p₀, temperature and sample morphology could be described. Under certain conditions, it is possible to visualise individual rate-determining steps and, thus, to arrive at conclusions on the reaction mechanism.     

Generalized-ensemble simulations of the human parathyroid hormone fragment PTH(1-34)

A generalized-ensemble technique, multicanonical sampling, is used to study the folding of a 34-residue human parathyroid hormone fragment. An all-atom model of the peptide is employed and the protein-solvent interactions are approximated by an implicit solvent. Our results demonstrate that generalized-ensemble simulations are well suited to sample low-energy structures of such large polypeptides. Configurations with a root-mean-square deviation to the crystal structure of less than 1 A are found. Finally, we discuss limitations of our implicit solvent model.     

Radioimmunoassay for parathyroid hormone (PTH): Characterization of commercially available antigens and antisera

Ohne ZusammenfassungSupported by Deutsche Forschungsgemeinschaft.     

Magnesium, parathyroid hormone and osteocalcin in the sera of hospitalized patients with chronic alcoholism

Levels of parathyroid hormone (PTH) and osteocalcin in hypomagnesemic sera of chronic alcoholism patients were carried out to evaluate the roles of chronic alcohol poisoning on bone metabolism. Serum gamma-GTP activity showed inverse relationships among serum Mg and osteocalcin in these patients and PTH levels were also more decreased in these patients than in healthy subjects. These results indicated that the direct actions of alcohol might be brought about by the deterioration of bone metabolism, due to the decrease of serum PTH and osteocalcin levels by chronic alcohol poisoning.     

Colorimetric measurement of serum and urine magnesium with the Cobas Mira Analyzer

Conclusion The major advantage of the xylidyl blue-1 method over kits using the calmagite reagent is the stability of the alkaline reagent mixture ready for use [5]. Furthermore, the kit benefits from fewer interferences than the calmagite procedure [3]. The kit performed well in terms of precision, sensitivity and linearity and the results correlate excellently with those by atomic absorption spectrophotometry.

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Colorimetrische Bestimmung von Magnesium im Serum und Urin mit dem Cobas Mira Analysator