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U Feldmann

Publications and source records attributed to U Feldmann.

At least 37 records · Page 2Linked to original sources
PubMed1989

Significance of latent hyperthyroidism.

In euthyroidism the circadian rhythm and pulsatility of TSH is well known. With regard to hyperthyroidism only very preliminary data were described. In this study we investigated the secretion pattern of the pituitary-thyroid axis hormones during 24 h in latent and overt hyperthyroidism and in euthyroidism with regard to common and different properties. Blood was obtained for 24 h at 10-min intervals. In euthyroidism we found intraindividually three overlapping patterns of TSH, which are different in amplitude and frequency and can be found interindividually, too. These patterns are equal to the circadian rhythm, pulsatile secretion and lastly to the methodic rustle. The circadian rhythm in latent hyperthyroidism is distinctly suppressed and in overt hyperthyroidism totally. Whereas in latent hyperthyroidism pulsatile secretion is extant, in overt hyperthyroidism the TSH pulses are absent. To record the patients' TSH circadian rhythm with only three blood samples, we defined the TSH-Triplex. In young as well as in elderly healthy volunteers it demonstrated significantly higher TSH levels at midnight (at 24:00 h) than it did at 4 p.m. and 8 a.m. The present study shows a significantly different TSH pattern in latent hyperthyroidism compared to euthyroidism. It should be discussed whether latent hyperthyroidism could be defined as hyperthyroidism stage I. On the other hand, latent hyperthyroidism could be an illness with its own cause, different from hyperthyroidism. Our data suggest that the laboratory findings of latent hyperthyroidism in each age are non-physiological. However, the cause for this disorder is unclear until now; hence further investigations are necessary.

Adult↗
PubMed1987

[Effect of 10% hydroxyethyl starch 200/0.5 and 10% dextran 40 on the flow property and coagulation of whole blood in vivo].

In randomized order 18 hypovolemic patients undergoing minor surgery received either 500 ml of 10% dextran 40 (n = 8) or 500 ml of 10% hydroxyethylstarch 200/0.5 (n = 10) preoperatively. There were no significant changes in hemoglobin, hematocrit, colloid osmotic pressure, total serum protein, platelet count, platelet aggregation and hemostatic tests. The shear dependent viscosity of whole blood was determined at the relevant range of 1.24-91.0 s-1. Both colloids cause a marked decrease of whole blood viscosity, which is detectable at low shear rates still 24 h later. Plasma viscosity shows no changes in either group. The criteria for preferring one of the colloids for decreasing the blood viscosity will depend on the incidence and severity of undesired adverse reactions.

Adult↗
PubMed1987

[The Mannheim peritonitis index. An instrument for the intraoperative prognosis of peritonitis].

Based on the experience with 1243 patients suffering from purulent peritonitis 255 patients of two surgical departments were studied prospectively in a cohort study. Lethality was 24%. For intraabdominal infection an index is established that allows for the first time to predict lethal outcome of the disease in the individual patient. For each index-score the expected mortality is given by a modern mathematical calculation. The 'Mannheim Peritonitis Index' includes only clinical risk-factors that are routinely documented pre- and intraoperatively. Methods of evaluation, validation and the comparison with other prognostic indices are presented.

Humans↗
PubMed1986

[Differential diagnosis of jaundice by combined noninvasive diagnostic means using a logistic discriminant analysis].

Using a logistic discriminant function we retrospectively evaluated the diagnostic value of laboratory features and abdominal sonography in 70 patients with jaundice. 18 patients had an extrahepatic obstruction of the common bile duct (EHO), 22 patients had metastatic liver disease (MLD) and 30 patients had an infectious or toxic hepatocellular disease (HCD). The sensitivity resp. specificity of the 5 laboratory values AP, GGT, GPT, GOT and bilirubin was 22% resp. 90% for diagnosing EHO, 82% resp. 79% for diagnosing MLD and 67% resp. 68% for diagnosing HCD. The diagnostic value determined by their Chi2-value was AP greater than GPT greater than bilirubin greater than GOT greater than GGT. An undoubtedly dilated common bile duct was seen in 56% of the patients with EHO and in none of the other patients. Metastatic lesions were seen exclusively in 81% of the patients with MLD. No distinct sonographic sign could be found for the patients with HCD. The combination of AP, GPT and bilirubin with the result of abdominal sonography in a logistic discriminant function led to a correct a posteriori classification of all patients. Using a mathematical classification model jaundiced patients can be diagnosed on the basis of noninvasive methods alone and invasive procedures should be restricted to therapeutic interventions.

Cholestasis, Extrahepatic↗
PubMed1985

[Prognostic significance of a preoperative risk check list].

The perioperative risk of lethal complications amounts to 0.02 to 0.4% dependent on different investigators. A further decrease of this perioperative risk has failed to occur in spite of most sophisticated methods of anesthesiology. We desire a safe classification of risk scores in order to calculate the prognosis of the individual patient who is scheduled for operation and anaesthesia. 15 anamnestical, clinical and blood chemistry data of 700 patients planned for general surgery were registered, intra- and postoperative complications were documented, and by means of statistical methods (discriminant analysis) evaluated. The patients' data were registered from the date of premedication to discharge or to four weeks after operation. To define the complications they were classified as mild, moderate and severe complications. The 15 variables used show a calculated risk prognosis of 40% for mild, 57% for moderate and 79% for severe complications. We find a very good correlation of the calculated versus observed risk of complications. The risk of mild complications are underestimated and severe complications overestimated.

Anesthesia↗
PubMed1984

Ehlers-Danlos syndrome type VI: collagen type specificity of defective lysyl hydroxylation in various tissues.

The Ehlers-Danlos syndrome type VI is an inherited disorder of collagen metabolism characterized by a defective lysyl hydroxylase. The resulting lack of hydroxylysine has been found in several connective tissues, all of which show varying degrees of clinical symptoms. In the present study, collagen was isolated from different connective tissues and the degree of hydroxylation of lysyl residues was determined. Subsequently, collagen types I, II, III, IV, and V have been prepared from a number of tissues. Insufficient hydroxylation of lysyl residues was found in type I and type III collagen, whereas types II, IV, and V showed normal amounts of hydroxylysine. The expression of the defect, even for type I and type III collagen, varied widely from one tissue to another. A complete lack of hydroxylysine was observed in skin, while it was less pronounced in tissues such as bone, tendon, lung, or kidney. The data suggest the presence of several isoenzymes having varying affinities to the different collagen types.

Adult↗
PubMed1983

Biochemical characterization of variants of the Ehlers-Danlos syndrome type VI.

Three variants of the Ehlers-Danlos syndrome type VI are described: a severe form with skeletal, dermal and ocular manifestations associated with a lack of hydroxylysine in skin and little lysyl hydroxylase activity in cultured fibroblasts; a similarly affected form with a nearly normal hydroxylsine content in skin, but with only little enzyme activity in cultured fibroblasts; and a predominantly ocular form with no biochemical abnormality in skin or cultured skin fibroblasts. The activities of prolyl 4-hydroxylase and the two hydroxylysyl glycosyltransferases were normal in all cases, and the failure to find lysyl hydroxylase activity was not due to altered solubility characteristics of the enzyme or to the presence of an enzyme inhibitor. The collagen produced in cell culture, however, was hydroxylated to a markedly higher extent than that found in skin. In both the mutant and control cells hydroxylation of lysyl residues was less sensitive to ascorbate deficiency than that of prolyl residues.

Adolescent↗
PubMed1981

A multivariate approach for the biometric comparison of analytical methods in clinical chemistry.

The structural relationship model is recommended for the comparison of analytical methods in clinical chemistry. This model is based on the partition of the observed measurements of the different methods in 2 hypothetical random variables: the "expected values", which represent the correct value of the analyte with no error of measurement, and the "error term" representing the measurement errors. it is assumed, that both these variables are normally distributed. There exists a linear structural relation between different analytical methods for the same analyte, provided the correlation coefficient between each pair of the expected values of these models is 1. This linear structural relationship is expressed by the mean values mui and standard deviations alpha i of the expected values, whereas the standard deviations of the error terms determine the precision of the methods. As a measure of the precision the coefficient of determination R(2)i is recommended. The model of structural relationship is an extension of th well known regression models and gives a more realistic approach to the comparison of 2 or more analytical methods. With 2 methods the standardized principle component should therefore replace the regression analysis. The slope of this principle component is identical with the ratio sy/sx. Statistical methods for the estimation and for the tests of hypotheses of the parameters are derived and demonstrated with an example.

Chemistry, Clinical↗
PubMed1980

[Prognosis of metastatic renal cell carcinoma related to the pattern of metastasis (author's transl)].

Hundred nine unselected patients with metastatic renal cell carcinoma have been stratified into 3 groups according to their type of metastasis: 17 patients with sceletal involvement only, 67 patients with visceral metastases, and 21 patients with a mixed type of metastasis. Four patients with a locoregional pattern of recurrence were not included in the analysis. The survival data (evaluated by life table analysis and a modified Wilcoxon-Rang-test) revealed a better prognosis for patients presenting exclusively with osseous metastases compared to the group with visceral metastases. The patients with osseous metastases showed a median survival time from diagnosis of 29.9 months compared to 11.6 months in patients with visceral involvement. Considering only patients whose metastases have been detected after a period of latency post nephrectomy, there is a further increase in the survival in favour of the patients with sceletal metastases and the difference to the group with visceral metastases becomes statistically highly significant.

Abdominal Neoplasms↗
PubMed1980

[Quantimetric investigations of the time of death by estimating the postmortem threshold (rheobase) of human skeletal muscles to electric stimulus by direct current (author's transl)].

We recently reported on an unusually high correlation between the post mortem interval and the postmortem (pm) increase of the muscular threshold to galvanic stimuli (Rheobase) in the skeletal muscle of the rat. To find out whether a practicable method of estimating the time of death could be developed out of this, we investigated skeletal muscles of 11 individuals having died from various causes. The muscles were stimulated electrically by square-impulses of 1 s length at 200 V, the strength ranging from 0.1 to 80 mA. The electrodes were applied to the skin. A strong correlatin (r = 0.98 on average) between the muscular threshold to electric stimuli and the time of pm investigation was also found in human muscles and can be described by the Formula Y(T)[mA] = A*Exp(b . T) when A* is the primary threshold (Rheobase) and T the time of pm interval. Differentiation of this equation leads to a strongly linear regression curve by which finally the time of death can be expressed as (formula: see text). The coefficients a0 and b can be calculated by the linear regression of the pm Rheobase in a semi-logarithmic system of coordinates and a* as lnA* [mA] from the course of the regression curves--a0 = lnA0 [mA] at the beginning of the investigation and b [l/min] = gradient of the regression. The testing of the muscles flexor digiti V and flexor digitorum communis brevis, in particular, lead to the most exact results. By this method immediate results of hitherto unknown reliability can be achieved in estimating the time of death up to 15 h postmortem by statistical means of calculation. Changing temperatures, different causes of death, and other individual factors seem to be of no influence on the results so that collectives of known characteristics are not necessary for comparison.

Adult↗
PubMed1979

Biochemical characteristics of Ehlers-Danlos syndrome type VI in a family with one affected infant.

The parents of a child with the clinical symptoms of Ehlers-Danlos syndrome type VI were identified as third-degree cousins. Biochemical analysis of the dermis of the patient revealed a complete lack of hydroxylysine in the dermal collagen. The dermis of both parents contained only half the amount of hydroxylysine found in healthy individuals. Hydroxylation of prolyl residues was normal in the skin of the patient and his parents. Investigation of the collagen synthesized by fibroblasts derived from the skin of the patient showed a normal proportion of type I and type III collagen. However, while hydroxylation of prolyl residues was normal in type I and type III collagen, hydroxylation of lysyl residues was markedly lower than normal in both type I and type III collagen.

Collagen↗
PubMed1979

Comparison of 9 methods for the determination of cholesterol.

Seven enzymatic procedures for the determination of cholesterol in serum were compared with the Liebermann-Burchard- and a gas-chromatographic method. Using a decision matrix all methods could be ranked according to reliability and practicability . With the exception of the cholesterol oxidase-coupled Kageyama principle and the Liebermann-Burchard procedure, all the other methods showed similar reliability.

Autoanalysis↗
PubMed1979

Studies on the methodology and evaluation of the lymphocyte transformation microtest.

Optimum experimental conditions for the lymphocyte transformation microtest in healthy persons are described. The dependence of PHA stimulation on duration of culture, additions of serum and PHA concentration is investigated. A function of normal distribution pattern can be set up by determining the lymphocyte stimulability with four different PHA concentrations in the optimal stimulation range. With this function, the area under the curve, steepness, position and height of the maximum can be calculated. These parameters should serve for better interpretation of cellular immunity.

Adult↗