34 results on '"Christiansen C"'
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2. Changes in calcanean bone mineral occurring spontaneously and during hormone replacement therapy in early post-menopausal women
- Author
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Svendsen, O. L., primary, Hassager, C., additional, Marslew, U., additional, and Christiansen, C., additional
- Published
- 1992
- Full Text
- View/download PDF
Catalog
3. Bone mass measured by photon absorptiometry: comparison of forearm, heel, and spine
- Author
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Hansen, M. A., primary, Riis, B. J., additional, Overgaard, K., additional, Hassager, C., additional, and Christiansen, C., additional
- Published
- 1990
- Full Text
- View/download PDF
4. Vitamin D metabolites – relation to age, menopause and endometriosis
- Author
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Hartwell, D., primary, Rødbro, P., additional, Jensen, S. B., additional, and Christiansen, C., additional
- Published
- 1990
- Full Text
- View/download PDF
5. Discriminative ability of total body bone-mineral measured by dual photon absorptiometry
- Author
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Gotfredsen, A., Pødenphant, J., Nilas, L., and Christiansen, C.
- Abstract
We investigated the discriminative ability of total body bone-mineral expressed as the total body bone-density (TBBD) measured by dual photon absorptiometry (DPA) in 79 healthy premenopausal women, 27 healthy postmenopausal women, and 120 female osteoporotic fracture patients presenting with either Colles' fracture, vertebral fracture or femoral neck-fracture. TBBD was compared to the bone-mineral density of the lumbar spine (BMDspine) also measured by DPA, and to the bone-mineral content of the forearms (BMCforearm) measured by single photon absorptiometry (SPA). TBBD, BMDspinc and BMCforearm showed that all the fracture patient groups had significantly reduced bone-mass. Using receiver operating characteristic (ROC) analysis, we found that TBBD had a tendency towards better discriminative ability than BMDspinc or BMCforearm with regard to the discrimination between healthy premenopausal women and the three types of osteoporotic fractures (not significant in spinal fracture patients). BMCforearm had an intermediate position, whereas BMDsplne had the smallest discriminative ability. TBBD also discriminated better between healthy postmenopausal women and hip-fracture patients than BMDspine or BMCforearm, whereas there was no significant difference between the three methods regarding the discrimination between the healthy postmenopausal women and the Colles' and spinal fracture patients. We conclude that the TBBD measurement by DPA has a discriminative potential which is better than the local spine or forearm measurements. more...
- Published
- 1989
- Full Text
- View/download PDF
6. Creatine kinase isoenzyme MB assay by electrophoresis
- Author
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Grande, P., Christiansen, C., and Naestoft, J.
- Abstract
A method for determination of the creatine kinase isoenzyme MB (CK-MB) is reported: separation of the isoenzymes was done by electrophoresis and the activity of the isoenzyme bands quantitated by scanning fluorometry. Total CK activity was used for calculation of CK-MB level. The precision of the method was satisfactory: coefficient of variation 5-10%. Its accuracy good: CK-MB was consistently found in high concentrations in tissue extracts of myocardium, but was virtually absent in skeletal muscle and could not be demonstrated in serum from patients with skeletal muscle damage. The sensitivity of the method fitted its clinical use: CK-MB was undetectable (<5 U/l) in normal sera, below 30 U/l in seventy-six out of seventy-seven patients in whom the diagnosis of acute myocardial infarction (AMI) was disproved, and above 30 U/l in all seventy-two patients with AMI according to WHO criteria. The CK-MB concentration in serum rises to a maximum about 20 h after onset of clinical symptoms of AMI and reaches baseline levels 20-30 h later. The electrophoretic CK-MB method is easy, fast and reliable and is considered as an important diagnostic test for AMI. more...
- Published
- 1979
- Full Text
- View/download PDF
7. Bone Mineral Content in the Forearm Measured by Photon Absorptiometry Principles and Reliability
- Author
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Christiansen, C., Rödbro, P., and Jensen, H.
- Abstract
A method for estimating total bone calcium is reported. The method is based on two-dimensional scanning photon absorptiometry on the distal part of the forearm. The following factors are investigated: precision of measurements on standards and human subjects; linearity; the effect of varying bone orientation; amount of fat and soft tissue; and the relation between weight and content of calcium and phosphate. The results show that the method is eminently suitable for rapid, easy, and atraumatic measurement of local bone calcium in vivo. more...
- Published
- 1975
- Full Text
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8. Estimation of total body composition from single photon absorptiometry measurement of forearm fat content
- Author
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Hassager, C., Nielsen, B., and Christiansen, C.
- Abstract
The forearm fat content (FATarm, measured by single photon (125I) absorptiometry) and the 24-h urinary creatinine excretion (24 Ucrea) were determined in 29 healthy adults (12 males and 17 females), whose total body fat percentage was measured by three different methods: (i) Dual photon (l53Gd) absorptiometry (DPA); (ii) body density measurements (BD); and (iii) total body potassium determinations (TBP). Lean body mass (by DPA, BD, and TBP) correlated significantly with 24 Ucrea (r=0.87-0.89, standard error of estimate (SEE)=5.2-6.3 kg). The total body fat percentage could be predicted from FATarm with SEEs at 3.4-5.8 (r=0.85-0.88) and from 24 Ucrea+body weight with SEEs at 5.1-7.5 (r=0.61-0.72). We conclude that the FATarm measurement represents a new tool for simple assessment of body composition on a group basis. more...
- Published
- 1989
- Full Text
- View/download PDF
9. Serum vitamin D metabolites in normal subjects after phototherapy
- Author
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Staberg, B., Christiansen, C., and Rossing, N.
- Abstract
The serum concentrations of the major vitamin D metabolites (25-hydroxy-vitamin D(2+3) (25-OH-D), 1,25-dihydroxyvitamin D(2+3) (1,25-(OH)2-D), and 24,25-dihydroxyvitamin D(2+3) (24,25-(OH)2-D)) were studied in 22 healthy male volunteers before and after one or two treatments with whole body UVB or PUVA in conventional doses. The effect of UVB was investigated in the autumn and early spring, whereas the effect of PUVA was investigated only in the autumn.The pre-treatment values of two metabolites were significantly reduced in the spring compared to the autumn level (25-OH-D : 14.0 nd/ml versus 22.0 ng/ml, P < 0.02; and 24,25-(OH)2-D : 1.23 ng/ml versus 2.74 ng/ml, P<0.01), whereas the serum concentration of 1,25-(OH)2-D was not significantly reduced in the spring. After UVB, a small, but not significant, rise in all metabolites was observed in the spring, whereas virtually no changes were measured after UVB or PUVA in the autumn.We conclude that UVB and PUVA do not lead to harmful concentrations of vitamin D metabolites in the blood of healthy subjects. more...
- Published
- 1984
- Full Text
- View/download PDF
10. Bone Mineral Content and Estimated Total Body Calcium in Normal Children and Adolescents
- Author
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Christiansen, C., Rödbro, P., and Nielsen, C. Thöger
- Abstract
Bone mineral content in the distal part of the forearm was measured in 301 normal children and adolescents aged from 7-20 years to estimate total body calcium in these age groups. From year 7 to 9 and from year 15 to 20 the mean values in boys were significantly higher than those in girls. In the lower age groups there was a slow increase in estimated total body calcium with age, followed by a sharp increase at the age of puberty. more...
- Published
- 1975
- Full Text
- View/download PDF
11. Discrepancy between serum concentrations of 1,25-dihydroxyvitamin D metabolites measured by radio-immunoassay and thymus radioreceptor assay during vitamin D2 treatment
- Author
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Hartwell, D., Johansen, J. S., and Christiansen, C.
- Abstract
A radio-immunoassay (RIA) for determination of 1,25-dihydroxycholecalciferol (l,25(OH)2D3) and 1,25-dihydroxyergocalciferol (1,25(OH)2D2) in serum was compared with a competitive protein binding assay using calf thymus receptor to clarify the comparability of measurements in subjects treated with either vitamin D2 or vitamin D3 (4000 IU per day for 8 weeks). Before and during treatment with vitamin D3 the two assay techniques were concordant, but during vitamin D2 treatment the serum concentrations of 1,25(OH)2D2 and 1,25(OH)2D3 were higher when measured by RIA. The study demonstrates that during vitamin D2 treatment unknown compounds, recognized only by the antiserum, co-elute with 1,25(OH)2D2 and 1,25(OH)2D3 in high pressure liquid chromatography. It can be concluded that the radio-immunoassay used here cannot replace the calf thymus receptor assay. more...
- Published
- 1989
- Full Text
- View/download PDF
12. Regional Bone Mineral in Healthy and Osteoporotic Women: A Cross-Sectional Study
- Author
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Gotfredsen, A., Nilas, L., Pødenphant, J., Hadberg, A., and Christiansen, C.
- Abstract
Regional bone mineral content and density (BMC and BMD) was measured in six regions (head, arms, chest, spine, pelvis, and legs) using dual photon 153Gd absorptiometry (DPA) in 128 healthy women aged 21-77 years, and in 45 women presenting with Colles' fracture (mean age 65 years), 46 women with vertebral crush or wedge fracture (mean age 68 years), and 27 women with femoral neck-fracture (mean age 74 years). The age-related normal bone loss was generalized, uniformly distributed, and best described by a combination of a premenopausal linear and a postmenopausal exponential regression in all six regions. Looking at BMD, the overall expected bone loss from age 20 to age 80 was approximately 20% in all the regions. When the fracture patients were examined, we found also generalized bone deficit as the prominent feature, amounting to about 20% of the premenopausal level for Colles' and spinal fractures, and about 25% for femoral neck-fracture. However, there was a regional bias in the fracture patients, as the Colles' and spinal fracture patients had a preferential reduction in spinal and pelvic BMD, whereas the patients with femoral neck-fracture had a preferential reduction in pelvic and leg BMD. We conclude that age-related and osteoporotic bone loss is generalized. Furthermore, we propose that regional differences in osteoporotic bone loss are brought about by a simple biological variability of the range of (i) relative amount of trabecular and cortical bone, (ii) rate of loss in the two types of bone tissue, and (iii) time of onset of trabecular relative to cortical bone loss. more...
- Published
- 1989
- Full Text
- View/download PDF
13. Estimation of Total Body Calcium from the Bone Mineral Content of the Forearm
- Author
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Christiansen, C. and Rödbro, P.
- Abstract
The representativity of forearm in bone mineral content (BMC) measurements for estimation of total body calcium is investigated in this article. It is shown that there is a very high correlation between weight and calcium content of examined bone pieces, that there is a high correlation between weight of individual bones and BMC values, that the BMC values from various parts of the skeleton are reasonably well correlated, that the weight of individual bones is highly correlated to the weight of total skeleton, and that there is a reasonably high correlation (r=0.85) between BMC measurements in the distal part of the forearm and total weight of the skeleton. It is concluded that BMC measurements of the distal part of the forearm give an estimate of total body calcium. more...
- Published
- 1975
- Full Text
- View/download PDF
14. Bone Mineral Content and Estimated Total Body Calcium in Normal Adults
- Author
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Christiansen, C. and Rödbro, P.
- Abstract
Bone mineral content (BMC) was measured in 127 normal subjects, 54 men and 73 women, aged 21-70 years. BMC was a function of age and sex; it was therefore found relevant to give normal values in 10-year age groups for each sex. BMC was furthermore related to height, weight, surface area, and muscular strength, but the biological scatter was not reduced by correction for surface area. The normal range is expressed in arbitrary units, mmol calcium/m, and calculated total body calcium in grams. Since the latter expression, after determination of the necessary proportion constants, is independent of apparatus construction and location of measurement, and is dependent on the selection of the reference population, it is recommended that the result be expressed in these grams. It is furthermore concluded that the BMC measurement is excellently suited for determining the effect of treatment on osteopenia in a group of patients but rather unsuitable for diagnosis of osteopenia in the individual patients, whereas two other conditions (as regards clinical applicability) occupy an intermediate diagnosis of osteopenia in a group of patients. more...
- Published
- 1975
- Full Text
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15. Treatment of Osteoporosis with Calcium Infusions an Osteodensitometric Study
- Author
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Jensen, H., Christiansen, C., Munck, O., and Toft, H.
- Abstract
It has recently been suggested that osteoporosis results from an imbalance between the secretion of parathyroid hormone and thyrocalcitonin, resulting in a net loss of calcium, and that intermittent hypercalcaemia might reverse this imbalance. This hypothesis was tested in five women with postmenopausal osteoporosis by giving 12 calcium infusions on 12 consecutive days. The bone mineral content was measured by means of osteodensitometry, which was performed at regular intervals before, during, and after the infusions. The treatment did not result in any significant alteration in bone mineral content. more...
- Published
- 1973
- Full Text
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16. The Functions and Metabolites of Vitamin D and their Possible Implications in Osteoporosis
- Author
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Christiansen, C., primary
- Published
- 1988
- Full Text
- View/download PDF
17. Long-term reproducibility of bone mineral content measurements
- Author
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Christiansen, C., primary and Roödbro, P., additional
- Published
- 1977
- Full Text
- View/download PDF
18. Development of a monoclonal antibody to urinary degradation products from the C-terminal telopeptide alpha 1 chain of type I collagen. Application in an enzyme immunoassay and comparison to CrossLaps ELISA.
- Author
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Fledelius C, Kolding I, Qvist P, Bonde M, Hassager C, Reginster JY, Hejgaard J, Frøokiaer H, and Christiansen C
- Subjects
- Adult, Aged, Amino Acid Sequence, Antibodies, Monoclonal biosynthesis, Antibodies, Monoclonal isolation & purification, Antibody Specificity, Bone Resorption immunology, Bone Resorption urine, Collagen chemistry, Collagen Type I, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunoenzyme Techniques, Middle Aged, Peptide Fragments chemical synthesis, Peptides chemistry, Postmenopause, Premenopause, Antibodies, Monoclonal chemistry, Collagen immunology, Collagen urine, Peptide Fragments immunology, Peptide Fragments urine, Peptides immunology, Peptides urine
- Abstract
A monoclonal antibody MAbA7 was raised against a synthetic peptide having a sequence (EKAHDGGR) specific for a part of the C-telopeptide alpha 1 chain of type I collagen. MAbA7 was labelled with horseradish peroxide and used in a competitive one-step enzyme-linked immunosorbent assay (ELISA) for measurement of urinary type I collagen degradation products. The assay was technically evaluated and preliminary clinical data are presented. The measuring range was 200-7000 micrograms l-1 with a detection limit of 25 micrograms l-1. Within-run and total CVs were 5.5 and 8.0%, respectively. Analytical recovery averaged 96.6% +/- 5.3 (mean +/- 1SD). Values obtained in the ELISA were highly correlated (r = 0.93) to values obtained by a commercially available assay (CrossLaps ELISA) known to measure urinary degradation products derived from the C-telopeptide of type I collagen reflecting the rate of bone resorption. Investigation of the urinary fragments responsible for the immunological response in the two assays revealed, however, that they are not identical. Values obtained in urine samples from postmenopausal women (n = 108) and patients with Paget's disease (n = 6) increased 43% (p < 0.01) and 28-fold (p < 0.001), respectively, when compared to a premenopausal level (n = 50). A decrease in the urinary concentrations of 67% (p < 0.01) was seen after 6 months in urine samples from postmenopausal women (n = 13) receiving hormone replacement therapy (HRT) compared to a group receiving placebo (n = 9). Likewise, the urinary concentrations decreased 88% (p < 0.001) in early postmenopausal women receiving bisphosphonate therapy (n = 11) for a period of 9 months compared to a group receiving placebo (n = 12). These results suggest that the monoclonal antibody and the new assay may be useful for further investigations of the physiological and clinical importance of type I collagen degradation. more...
- Published
- 1997
- Full Text
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19. Effect of physical training on serum lipids and serum HDL cholesterol in young men.
- Author
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Hørby-Petersen J, Grande P, and Christiansen C
- Subjects
- Adult, Body Weight, Cholesterol, HDL, Humans, Male, Cholesterol blood, Lipids blood, Lipoproteins, HDL blood, Physical Education and Training
- Abstract
To examine the effect of physical training on serum lipoproteins and lipids a group of 54 young males participated in a longitudinal study. The participants underwent a supervised physical training programme for 12 weeks. Initially and at the end of the training period the group was exercise-tested on an ergometric bicycle, performed a 12-min run test, and had blood samples drawn for determination of serum lipoproteins and lipids. Although maximum oxygen uptake (P less than 0.001) and the distance run (P less than 0.01) were significantly increased after physical training, we found virtually unchanged body weight and serum levels of HDL cholesterol, total cholesterol and triglycerides. It is suggested that the previously described effects of physical training on HDL cholesterol is caused by a body weight reduction rather than changes in physical condition. more...
- Published
- 1982
20. A selective and simplified radioimmunoassay of 25-hydroxyvitamin D3.
- Author
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Hummer L, Nilas L, Tjellesen L, and Christiansen C
- Subjects
- Humans, Immune Sera, Calcifediol blood, Radioimmunoassay methods
- Abstract
A simple, non-chromatographic and selective assay for determination of 25OHD3 in serum is described. The serum sample is deproteinated with acetonitrile and the supernatant purified over a small prepacked cartridge, Sep-pak. In the eluate from the cartridge, 25OHD3 is measured by radioimmunoassay. The selectivity of the assay for 25OHD3 is improved by adding vitamin D2 to the antiserum; the assay is thus capable of measuring 25OHD3 in serum samples containing up to a ratio of 25OHD2/25OHD3 equal to 150. The simplicity, speed and the small amount of sample needed (0.5 ml) make this method suitable for use in a routine clinical laboratory. Because of its selectivity for 25OHD3 the assay is a necessary prerequisite in the further investigation of metabolic discrimination between vitamins D2 and D3. more...
- Published
- 1984
- Full Text
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21. Vitamin D metabolites in normal subjects during one year. A longitudinal study.
- Author
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Tjellesen L and Christiansen C
- Subjects
- 25-Hydroxyvitamin D 2, Adult, Calcifediol blood, Ergocalciferols analogs & derivatives, Ergocalciferols blood, Female, Humans, Longitudinal Studies, Male, Reference Values, Seasons, Vitamin D blood
- Abstract
The serum concentrations of 25-hydroxycholecalciferol (25OHD3), 25-hydroxyergocalciferol (25OHD2), 24,25-dihydroxyvitamin D (24,25(OH)2D), and 1,25-dihydroxyvitamin D (1,25(OH)2D) were measured in 10 normal subjects every 2 months for 1 year. Parallel seasonal variations were found in serum 25-hydroxycholecalciferol and 24,25-dihydroxyvitamin D reaching maximum values in June. Moreover, a highly significant correlation between changes in these two metabolites was observed (r = 0.89, P less than 0.001). On the other hand, the mean serum 1,25-dihydroxyvitamin D concentration remained constant throughout the year. Our data add further evidence to the tight regulatory mechanism of serum 1,25-dihydroxyvitamin D and the lack of regulatory mechanism of serum 24,25-dihydroxyvitamin D. more...
- Published
- 1983
22. Vitamin D metabolites in diabetic patients: decreased serum concentration of 24,25-dihydroxyvitamin D.
- Author
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Christiansen C, Christensen MS, McNair P, Nielsen B, and Madsbad S
- Subjects
- 24,25-Dihydroxyvitamin D 3, 25-Hydroxyvitamin D 2, Adult, Calcifediol blood, Calcitriol blood, Diabetes Mellitus drug therapy, Ergocalciferols blood, Humans, Insulin therapeutic use, Male, Middle Aged, Diabetes Mellitus blood, Dihydroxycholecalciferols blood, Ergocalciferols analogs & derivatives, Vitamin D blood
- Abstract
In order to elucidate if changes in vitamin D metabolism play a role for diabetic bone loss, the serum concentrations of the major vitamin D metabolites were studied in 26 adult male ambulatory insulin-treated diabetics, selected to have normal renal function and a duration of diabetes below 11 years. The patients were studied during usual metabolic control and exhibited wide ranges of hyperglycaemia and glycosuria. The serum concentrations of the major metabolites of vitamin D, 25-hydroxyvitamin D(2 + 3) (25OHD), 24,25-dihydroxyvitamin D(2 + 3) (24,25(OH)2D), and 1,25-dihydroxyvitamin D(2 + 3) (1,25(OH)2D), were measured in diabetics, and in age and sex matched controls. The diabetics had slightly decreased serum levels of 25OHD (42.0 nmol/l versus 55.5 nmol/l in normals, P less than 0.05), markedly decreased serum levels of 24,25(OH)2D (2.98 nmol/l versus 5.91 nmol/l, P less than 0.01), but serum levels of 1,25(OH)2D were virtually normal (64.2 pmol/l versus 68.3 pmol/l, ns). The close correlation between serum concentrations of 25OHD and 24,25(OH)2D observed in the normal subjects, was absent in the diabetics. There were no correlations between the serum levels of any of the vitamin D metabolites and the measured indices of glucose and calcium metabolism. It is concluded that insulin-dependent diabetic patients demonstrate definite alterations in serum levels of vitamin D metabolites, the significance of which remains unknown at present. more...
- Published
- 1982
23. An easy and reliable radioimmunoassay of serum androstenedione: age-related normal values in 252 females aged 2 to 70 years.
- Author
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Hummer L, Nielsen MD, and Christiansen C
- Subjects
- Adolescent, Adult, Age Factors, Aged, Child, Child, Preschool, Female, Humans, Middle Aged, Radioimmunoassay, Reference Values, Androstenedione blood
- Abstract
A simple, non-chromatographic radioimmunoassay for the measurement of androstenedione (A-dione) in serum and based on a commercially available antiserum is described. The antibody-bound fraction was separated from the free fraction by a gel-centrifugation procedure. The method was used to establish reference values for normal females, based on determination in 252 normal females from 2 to 70 years of age. The data support the statement that the decline with age after puberty in the overall production of A-dione is mainly caused by a reduction in the adreno-derived A-dione, since the mean concentration of A-dione in age-matched pre- and postmenopausal women was very similar more...
- Published
- 1983
24. Measurement of 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 in clinical settings.
- Author
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Hummer L, Tjellesen L, Rickers H, and Christiansen C
- Subjects
- 25-Hydroxyvitamin D 2, Chromatography, High Pressure Liquid, Ergocalciferols administration & dosage, Ergocalciferols blood, Humans, Methods, Radioimmunoassay, Vitamin D-Binding Protein blood, Calcifediol blood, Ergocalciferols analogs & derivatives
- Abstract
A quick and simple method for the selective measurement of 25-hydroxyvitamin D3 (25OHD3) and 25-hydroxyvitamin D2 (25OHD2) is described. It includes a rapid sample preparation technique and a combination of a selective radioimmunoassay for 25OHD3 and a competitive protein-binding assay using vitamin D-binding protein for the determination of total 25OHD, including 25OHD3 and 25OHD2. The method was compared with a procedure which include methanol/methylene chloride extraction and chromatography on Sephadex LH 20, and a procedure which includes HPLC and final quantification by u. v. detection. The methods were applied to three groups of patients in order to obtain information on how far assay procedures could be simplified for use in the clinical settings. It is concluded that the method described is applicable for following patients on vitamin D2 therapy. When groups of patients have to be compared, the mean values of the estimates are comparable, whether a simple method or a laborious method is used. Hence, the selection of assay method should take into account the clinical problem and the cost of the analysis. more...
- Published
- 1984
- Full Text
- View/download PDF
25. Clinical evaluation of different principles of CK-MB determination.
- Author
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Grande P and Christiansen C
- Subjects
- Chromatography, Chromatography, DEAE-Cellulose, Electrophoresis, Agar Gel, Humans, Immunoenzyme Techniques, Isoenzymes, Creatine Kinase blood, Myocardial Infarction enzymology
- Abstract
Seven methods commercially available involving different principles for determination of creatine kinase (E.C. 2.7.3.2) isoenzyme MB were compared. The methods employ quantitative electrophoresis, column chromatography, batch chromatography, and antibody inhibition techniques. Blood from 100 patients suspected of acute myocardial infarction was used to test the following factors: sensitivity, linearity, precision, accuracy, simplicity, and diagnostic comparability. The analytical quality of all the techniques investigated was almost satisfactory, and only minor differences were found in linearity and precision. The diagnostic quality was, however, somewhat limited. The number of positive and negative results varied significantly. The reference value given by the manufacturers did not agree, and each laboratory must establish its own reference ranges. more...
- Published
- 1983
26. Hydroxyproline/creatinine ratios as estimates of bone resorption in early postmenopausal women. Fasting and 24-h urine samples compared.
- Author
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Pødenphant J, Riis BJ, Larsen NE, and Christiansen C
- Subjects
- Clinical Trials as Topic, Double-Blind Method, Drug Combinations, Estradiol pharmacology, Estriol pharmacology, Female, Humans, Middle Aged, Norethindrone pharmacology, Bone Resorption drug effects, Creatinine urine, Estrogens pharmacology, Hydroxycholecalciferols pharmacology, Hydroxyproline urine, Menopause drug effects
- Abstract
Ratio of urinary hydroxyproline/creatinine excretion is often used as an index of bone resorption. To establish the difference between the fasting urinary content (FU-HPR/CR) and the 24-h urinary excretion (24 h-U-HPR/CR) we determined hydroxyproline and creatinine in specimens from a group of early postmenopausal women. One hundred and eighty-six early postmenopausal women were randomized into 10 groups receiving various doses of sequential female sex hormones and/or 1,25(OH)2D3, 0.25 microgram per day, or placebo. In all groups there were parallel changes of FU-HPR/CR and 24 h-U-HPR/CR, and in all groups treated with oestrogens the values decreased significantly. The changes in FU-HPR/CR were more pronounced than in the 24-h-U-HPR/CR, which indicates that FU-HPR/CR is a more sensitive marker of changes in bone resorption. The strong correlation between the mean values of 24-h-U-HPR/CR and those of FU-HPR/CR suggests that both methods are convenient for evaluating changes during long-term studies in groups of patients. The correlation on an individual basis is weak. The substantial intraindividual variation in 24-h-U-HPR/CR, (34.6%) indicates that FU-HPR/CR (CV = 17.0%) is the more valid variable for individual patients. more...
- Published
- 1986
- Full Text
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27. Testosterone treatment and arginine-induced growth hormone stimulation in male delayed puberty: effects on serum calcium, phosphate and vitamin D metabolites.
- Author
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Hyldstrup L, Christiansen C, Nielsen MD, and Transbøl I
- Subjects
- Adolescent, Humans, Male, Parathyroid Hormone blood, Puberty, Delayed blood, Arginine pharmacology, Calcium blood, Growth Hormone blood, Hydroxycholecalciferols blood, Phosphates blood, Puberty, Delayed drug therapy, Testosterone therapeutic use
- Abstract
Hormonal changes after arginine-induced growth hormone stimulation and subsequent testosterone treatment were examined in 5 patients classified as having male delayed puberty. All the patients responded well to growth hormone stimulation and a significant negative correlation was found between the delay in height age and the maximal growth hormone response, r = 0.80, P less than 0.05. The testosterone treatment did not alter this pattern. Changes in PTH, 25OHD, 24.25(OH)2D, and 1.25(OH)2D were examined at 24 h after the infusion. The results showed significant reductions in PTH (P less than 0.05) and 24.25 (OH)2D (P less than 0.05) and a possible increase in 1.25(OH)2D, whereas 25OHD remained unchanged. These results may support the conception of growth hormone as a common denominator of growth and bone metabolism. more...
- Published
- 1984
- Full Text
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28. Total and local bone mass before and after normalization for indices of bone and body size.
- Author
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Nilas L, Gotfredsen A, and Christiansen C
- Subjects
- Bone and Bones analysis, Female, Forearm, Humans, Lumbar Vertebrae analysis, Menopause, Middle Aged, Minerals analysis, Osteoporosis diagnosis, Radionuclide Imaging, Body Constitution, Bone and Bones diagnostic imaging
- Abstract
Both single and dual photon absorptiometry are excellent techniques for longitudinal studies, owing to their high precision. Because of large biological variations they are less suited for diagnosing bone disease in single subjects. In a homogeneous group of 161 women, bone mass in the distal forearm, spine, and whole body measured by photon absorptiometry was significantly related to various general indices of body size (r = 0.29-0.59). Normalization procedures for variations of these variables could only reduce the individual variation by 10-20%. Local indices of body size (i.e. bone width or scan area) were no better in the forearm or spine. Normalization for the projected skeletal area of the whole body could reduce the SD of the total body bone mineral (TBBM) from 322 to 126 grams (15-6%). This might imply that the normalized TBBM can be used for diagnostic purposes. more...
- Published
- 1986
- Full Text
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29. Plasma bone Gla protein concentrations in healthy adults. Dependence on sex, age, and glomerular filtration.
- Author
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Johansen JS, Thomsen K, and Christiansen C
- Subjects
- Adult, Age Factors, Aged, Female, Glomerular Filtration Rate, Humans, Male, Middle Aged, Osteocalcin, Reference Values, Sex Factors, Calcium-Binding Proteins blood
- Abstract
Plasma bone Gla protein (BGP) was determined by radio-immunoassay in 266 healthy adults, men (n = 132) and women (n = 134), aged 20-79 years. In the women aged 30-69 years, plasma BGP increased significantly with age (r = 0.44, p less than 0.001), and a particularly steep increase was seen from 1.1 +/- 0.5 (mean +/- 1 SD) in the fifth decade to 2.0 +/- 1.4 nmol/l in the seventh decade. In men, aged 30-69 years, no correlation was found between plasma BGP and age (r = -0.07, NS). Plasma bone Gla protein is removed from the circulation mainly by the kidneys and the increased plasma BGP in the women could be caused by decreased renal clearance. The interrelationship was analysed by means of partial correlation. When creatinine clearance was held constant in women, BGP still correlated positively with age (r = 0.40, p less than 0.001), but not with creatinine clearance (r = 0.003, NS) when age was fixed. Plasma BGP was significantly increased above normal in 35 patients with chronic renal failure (10.2 +/- 14.6 nmol/l). Non-linear regression analysis showed that plasma BGP was within the normal range when 24-h creatinine clearance was greater than 30 ml/min, and large increases in plasma BGP did not occur until the 24-h creatinine clearance was below 20 ml/min. We conclude that, in normal subjects and patients with mild to moderate renal failure, plasma elevations of BGP reflect increased bone turnover rather than decreased renal clearance. more...
- Published
- 1987
- Full Text
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30. Bone composition in the distal forearm.
- Author
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Nilas L, Nørgaard H, Pødenphant J, Gotfredsen A, and Christiansen C
- Subjects
- Adult, Aged, Female, Humans, Male, Menopause, Middle Aged, Bone and Bones analysis, Forearm
- Abstract
Recent data have indicated that measurements of bone mass in the very distal part of the forearm is superior to more proximal measurements in identifying osteoporosis. Bone slices from the distal part of the forearm were obtained from 16 necropsies and the trabecular fraction of the total dry bone weight was measured in adjacent bone slices, 8 mm thick. Prior to autopsy bone mass at the corresponding sites was measured using a multipath single photon absorptiometric method by which scans are obtained proximal (proximal BMC) and distal (distal BMC) to the site, where the ulna and radius are 8 mm apart. The accuracy of bone measurements at the two sites was virtually similar (r = 0.98 and r = 0.94, respectively). In both areas the amount of trabecular bone increased towards the metaphysis with a trabecular/cortical ratio ranging from 10 to 60% (wt/wt). If bone composition is known it is possible to estimate rates of bone loss from the two compartments. more...
- Published
- 1987
31. Determination of mono- and dihydroxy-vitamin D metabolites in normal subjects and patients with different calcium metabolic diseases.
- Author
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Hummer L, Riis BJ, Christiansen C, and Rickers H
- Subjects
- 24,25-Dihydroxyvitamin D 3, Chromatography, Gel, Chromatography, High Pressure Liquid, Humans, Radioligand Assay, Reference Values, Calcifediol blood, Calcitriol blood, Calcium Metabolism Disorders blood, Dihydroxycholecalciferols blood
- Abstract
Reliable assays to determine the vitamin D metabolites are useful aids in the study of disorders involving vitamin D metabolism, and in the evaluation of the response in patients receiving vitamin D treatment. We report here the establishment in our laboratory of a method capable of measuring 25(OH)D, (including 25(OH)D2 and 25(OH)D3), 1,25(OH)2D and 24,25(OH)2D in a single blood sample. The method involves methanol/dichloromethane extraction and Sephadex LH-20 chromatography. The monhydroxylated fraction was purified on Lipidex 5000 and separated in 25(OH)D2 and 25(OH)D3 on high pressure liquid chromatography (HPLC), followed by ultra violet absorbance (UV) detection. The dihydroxylated fraction was separated by HPLC and quantified by protein-binding assays. The method is precise and accurate. The vitamin D metabolites were measured in different groups of patients and in normal subjects. more...
- Published
- 1985
- Full Text
- View/download PDF
32. Bone turnover in healthy adults measured by whole body retention and urinary excretion of 99mTc-MDP. Normalization by bone mass.
- Author
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Thomsen K, Gotfredsen A, and Christiansen C
- Subjects
- Adult, Age Factors, Aged, Female, Humans, In Vitro Techniques, Male, Middle Aged, Minerals metabolism, Technetium Tc 99m Medronate urine, Bone and Bones metabolism, Menopause, Technetium Tc 99m Medronate metabolism
- Abstract
Whole body retention (WBR) and urinary excretion (UE) of 99mTc-diphosphonate, two complementary methods of measuring the total bone turnover, were performed in 161 normal subjects, 82 women and 79 men, aged 20-70 years. Both WBR and UE were a function of age in the women, whereas there were no age-dependent differences in the men. Between the women and men in identical age groups, the differences did not reach significance. Total body bone mineral (TBBM) was measured by dual photon absorptiometry (DPA) in all subjects. This was done in order to obtain expressions for bone turnover per bone mass as a function of age and sex. This correction emphasized the general picture seen in the raw WBR and UE data: bone turnover was constant in the men throughout life and in the women before the menopause, and only moderate differences were found between the sexes before the age of 50. After this age the mean female values increased sharply. It is noteworthy that none of the postmenopausal subjects showed low turnover values. Our data clearly demonstrate that an increase in bone turnover is part of the pathophysiology of the well-known bone loss in postmenopausal women. more...
- Published
- 1986
- Full Text
- View/download PDF
33. Comparisons between two receptor assays for 1,25-dihydroxyvitamin D.
- Author
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Hartwell D and Christiansen C
- Subjects
- Adult, Aged, Binding, Competitive, Ergocalciferols blood, Female, Humans, Intestinal Mucosa metabolism, Male, Middle Aged, Receptors, Calcitriol, Thymus Gland metabolism, Calcitriol blood, Ergocalciferols analogs & derivatives, Radioligand Assay methods, Receptors, Steroid metabolism
- Abstract
We present a competitive protein binding assay (CPBA) for 1,25(OH)2D employing 1,25(OH)2D receptor from calf thymus, which was compared with a CPBA-employing receptor from rachitic chick intestine. The thymus receptor assay was more sensitive, specific and precise than the intestinal receptor assay. The thymus receptor assay measured both 1,25(OH)2D2 and 1,25(OH)2D3 with equal affinity, whereas 1,25(OH)2D2 was 1.1 times less potent than 1,25(OH)2D3 in the displacement from the chick intestinal receptor. Mean serum values of 1,25(OH)2D in normal subjects, post-menopausal women, pregnant women, and patients with chronic renal failure measured by the two assay systems did not differ. Furthermore, both assays showed that 1,25(OH)2D was unchanged in post-menopausal women after treatment with vitamin D2 or vitamin D3, 4000 IU/day for 8 weeks. We conclude that the high sensitivity of the thymus receptor and the equal affinity for the D2 and D3 analogue make the thymus receptor assay a reliable alternative to the chick intestinal receptor assay. more...
- Published
- 1988
- Full Text
- View/download PDF
34. Discrepancy between serum 1,25-dihydroxycholecalciferol measured by radioimmunoassay and cytosol radioreceptor assay.
- Author
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Hummer L, Christiansen C, and Tjellesen L
- Subjects
- Adult, Aged, Chromatography, High Pressure Liquid, Female, Humans, Immune Sera, Male, Middle Aged, Calcitriol blood, Cytosol analysis, Radioimmunoassay, Radioligand Assay
- Abstract
A radioimmunoassay for determination of 1,25-dihydroxycholecalciferol (1,25(OH)2D3) in serum, was compared with the radioreceptor assay using cytosol receptor from rachitic chick intestine in order to clarify whether differences in specificity can explain discrepancies in the clinical application of the two techniques. In the literature, seasonal fluctuations in serum 1,25(OH)2D3 are only observed when using radioimmunoassay. Treatment of anticonvulsant osteomalacia with vitamin D3 results in a marked increase in radioimmunologically measured 1,25(OH)2D3, but no effect on the serum 1,25(OH)2D level, measured by the radioreceptor assay, could be observed. The present study demonstrates that another unknown compound is coeluted on high pressure liquid chromatography with 1,25(OH)2D3, and recognised only by the antiserum. It can be concluded that the present radioimmunoassay cannot replace the cytosol receptor assay or either supplement by measuring the 1,25(OH)2D3 metabolite only. more...
- Published
- 1985
- Full Text
- View/download PDF
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