Biomedical subjects
Publications and source records attributed to J Andresen.
Reference is made to various possibilities of examination in diagnosis and localisation of pheochromocytoma demonstrated by several cases. The best radiological examination is angiography using Seldinger method, which by means of skilled technique, good contrast media and an optimal treatment with receptor-blocking medicaments will guarantee excellent x-rays for clear tumor localisation without real complications.
In 2 unrelated families 9 males presented with ataxia, apraxia, and neuropsychological abnormalities or mental deficiency, inherited as an X-linked recessive syndrome with partial clinical expression in obligate female carriers. The symptoms were present in early childhood and were non-progressive. Additional findings in 2 males were congenital "club-feet" and generalized seizures. The affected males were 13-62 years old at the time of our examination. Chromosome abnormalities including fragile X fra(X) could not be demonstrated in any case. Results of metabolic screenings were also normal. The clinical picture with X-linked recessive inheritance distinguishes this syndrome from previously described inherited hereditary ataxias.
Quantitative radiologic measurements of the second left metacarpal bone were performed on 63 normal men and 71 normal women, 105 patients with non-dialyzed chronic renal failure and on 32 chronic hemodialyzed men and women. For prospective analysis 42 non-dialyzed patients and 31 patients on chronic hemodialysis were available. Measurements of the total width, medullary cavity and combined cortical thickness at the midshaft of the metacarpal bone were made on postero-anterior hand radiographs with a readout of 0.1 mm using a direct reading needle-tipped calliper. Hereafter the cortical area and metacarpal bone mass were calculated. Mean values of the various parameters in the patient groups were compared with mean values of age-matched normal controls. For the prospective analysis the calculated, yearly change of the various parameters during the observation period were compared with the yearly change in normal persons, being estimated by regression analysis between age and radiologic values. Measurements of the amount of bone in normals and in patients with chronic renal failure were reliable, the intraobserver variation coefficient varying from 0.7 to 2.5 per cent and the interobserver variation coefficient from 1.0 to 5.8 per cent. Changes in thickness of the soft tissue of the hand only slightly affected the values, a change of 10 mm resulted in a change of one per cent of the measured and calculated values. Metacarpal bone mass was significantly reduced in normal men and women older than 50 years of age compared with younger persons.(ABSTRACT TRUNCATED AT 250 WORDS)
The outer (D) and inner diameter (d) of the second metacarpal bone, the combined cortical thickness (D-d), cortical area (D2-d2) and bone mass [D2d2)/D2) were measured in 74 renal transplant (RT) recipients at the time of renal transplantation and in a prospective analysis of 60 recipients after transplantation. The RT patient group was made up of recipients who after renal transplantation developed osteonecrosis or spontaneous fractures (RT-ON/SF) and an age- and sex-matched renal control group of subjects who did not develop these complications (RT-C). At the time of renal transplantation, in renal transplant recipient men and women, significantly reduced values in D, D-d and D2-d2 was noticed. These findings could be explained by a higher ratio of bone resorption than formation at the periosteal surface. Following renal transplantation, significant increases in d were seen with significant decreases in D-d, D2-d2 and (D2-d2)/D2, probably due to endosteal bone resorption, whereas D was unchanged compared with normal control persons. In the total group and in RT-ON/SF women, D decreased significantly and in ON/SF, increased significantly with significant decrease in bone mass compared with normal women whereas no significant changes in the parameters were seen in RT-C women. These findings indicate that bone loss after transplantation continues at the periosteal surface in women. The bone loss was most markedly demonstrated in women, who subsequently develop osteonecrosis or spontaneous fractures, probably due to a combined periosteal and endosteal resorption of calcified bony tissue.
Methods for quantitative determination of bone mineral and bone mass in normal subjects and in patients with metabolic bone disorders can be measured by the Compton scattering technique, the neutron activation analysis, by measurement of metacarpal bone mass, by single and dual photon absorptiometry, and by quantitative computed tomography. Measurement on metacarpal bone (radiogrammetry) seems to be able to distinguish between resorption and/or new bone formation at the periosteal and/or endosteal surface. The intraindividual observer variation on combined cortical thickness (D-d), cortical area (D2-d2), metacarpal bone mass (D2-d2)/D2-varies from 0.7 to 2.5 per cent and the interindividual observer variation from 1.0 to 5.8 per cent. Single photon absorptiometry measures bone mineral content in the forearm with great precision. The reproducibility using repeated measurements and automatic selection of the measuring area is about one per cent and can be used to follow changes in mineral content with time in patients with metabolic bone diseases. The dual photon absorptiometry may be used for measurements of bone mineral content in lumbar spine, in the femoral neck and measurement of total body calcium with an accuracy of less than 6 per cent and a precision below 3 per cent. Quantitative computed tomography has the ability to measure trabecular and cortical bone both centrally and peripherally. Using CT scanning, scanner related changes with time (day-to-day variation +/- 4%), patient repositioning (less than 1.5%), and fat concentration (residual uncertainty of approximately 1/6 of the biologic variation) are important factors influencing the accuracy and reproducibility of the values of the measured bone mineral content.(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVES: PCR has been successfully used in research for the detection of C. trachomatis DNA in synovial samples. However, each research laboratory has developed its own PCR, making inter-laboratory comparisons difficult. To allow for standardization we evaluated two commercially available amplification systems originally designed for the examination of urogenital samples (Roche Amplicor Chlamydia PCR and Abbott LCX Chlamydia LCR), using them to analyse spiked and clinical synovial fluid (SF) samples from reactive arthritis (ReA), undifferentiated arthritis (UA), and rheumatoid arthritis (RA) patients. We compared their sensitivity in assays of clinical SF samples with our in-house developed C. trachomatis specific nested PCR. METHODS: SF was spiked with purified C. trachomatis elementary bodies (EB) and analyzed by the commercial assays. Clinical SF samplesfrom ReA (n=21), UA (n=79) and RA (n=50) patients were examined by the two commercial assays and our in-house PCR. RESULTS: Using SF samples spiked with defined numbers of C. trachomatis EB, the sensitivity of the commercial tests was high and similar to published PCR sensitivity. In clinical SF specimens the commercial assays was also able to detect CT; however, the in-house PCR was more sensitive. Out of 10 PCR-positive SF samples Amplicor tested positive in only 4/10 and LCX in only 3/10. The in-house PCR detected chlamydial DNA in synovialfluidfrom 5/21 ReA (24%), 5/79 UA (6%) and in none of the 50 RA patients. CONCLUSION: Commercial amplification assays allow the detection of C. trachomatis in clinical specimens, although with a lower sensitivity than optimized PCR. Potential explanations are discussed.