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E Schifferdecker

Publications and source records attributed to E Schifferdecker.

31 records · Page 2Linked to original sources
PubMed1988

Linkage of HLA-DR beta specific restriction fragment length polymorphisms with Graves' disease.

HLA-DR3 positive patients with Graves' disease (6 homozygotes, 7 heterozygotes, i.e. yielding 19 haplotypes) were studied by restriction fragment length polymorphism analysis using TaqI as restriction enzyme in order to look for polymorphisms in the HLA-DR3 allele of the human major histocompatibility complex. Polymorphic TaqI fragments of 11.6, 9.8 and 5.8 kb, each corresponding to HLA-DR beta sequences, were shown to differ in their prevalence in patients with Graves' disease and controls. The prevalence of DR3 polymorphisms in a total of 35 HLA-DR3-containing haplotypes was markedly different within patients with Graves' disease and Caucasian controls. Whereas a 11.6 kb fragment was rare in Graves' disease (2/19 haplotypes vs 8/16 in controls), the inverse ratio was found for a 9.8 kb fragment, with a prevalence of 17/19 and 8/16 haplotypes, respectively. A polymorphic fragment of 5.8 kb was exclusively seen in two DR3-containing haplotypes of patients with Graves' disease. Our data provide evidence that a DNA polymorphism of the HLA-DR beta genes, which is also reflected at the product level, is linked to Graves' disease.

Cell Line↗
PubMed1987

[Plasma renin activity and aldosterone behavior in critically ill patients].

To investigate the influence of critical illness on plasma renin activity and aldosterone levels and to examine potential inhibitory effects of dopamine therapy on aldosterone responsiveness, we measured plasma renin activity, and potassium and creatinine in serum, as well as the responses of aldosterone, cortisol and prolactin levels to TRH 200 micrograms i.v. + Synacthen 0.25 mg i.v. in 63 unselected, critically ill patients (32 females, 31 males, aged 18-84 years). Of the patients 19 received dopamine treatment (3-13 micrograms/kg/min i.v.); 21 of the patients died in the further course of their disease. Plasma renin activity was increased in 66.7% of the patients and aldosterone levels were elevated in 90.5% of the patients. There were correlations (P less than 0.05) of lethality with plasma renin activity and cortisol levels and correlations (P less than 0.01) of aldosterone concentrations with plasma renin activity and cortisol levels. Whereas dopamine treatment had no inhibitory effect on aldosterone levels before and after stimulation, prolactin stimulation was decreased in dopamine-treated patients. Thus, dopamine does not generally lose its potency of hormone inhibition in critically ill patients, but has no influence on the secondary aldosteronism developing regularly in the early phase of critical illness, which is apparently mainly due to the stimulatory effect of ACTH (or ACTH-related pituitary peptides) and is considered an epiphenomen of the stress mechanisms acting upon the patients in this condition.

Aldosterone↗
PubMed1986

Technical mishaps as easily avoidable causes of treatment failure when using pumps for pulsatile administration of gonadotropin-releasing hormone.

A patient (19 years old) with Kallmann's syndrome was treated with gonadotropin-releasing hormone (2.5-16 micrograms) administered subcutaneously every 2 h using a portable infusion pump. During 42 weeks of treatment testosterone levels and testicular size did not increase sufficiently although no reasons for this insufficient response were detectable. Therefore the regime of controlling and changing the catheter system was intensified. By this means partial occlusions of the catheter were detected and could be corrected. Afterwards testosterone levels increased immediately and persistently to normal values.

Adult↗
PubMed1986

[Determination of TSH receptor antibodies--clinical value].

In 223 patients suffering from Graves' disease, TSH receptor autoantibodies in serum were measured using the commercially available TRAK assay (Henning, Berlin). Of 53 patients examined before treatment, 50 (94%) were TRAK-positive. During drug therapy the number of positive titers decreased. Of 38 patients examined after a therapy course for the first time, only two (5.3%) were positive. Evaluation of antibody status after all three forms of treatment (drugs, surgery, radioiodine) in 146 patients showed that of 33 patients with persistently positive titers only nine relapsed. Of the 24 patients out of this group without relapse, 15 had operative or radioiodine treatment. The 113 patients becoming or remaining TRAK-negative after treatment showed 12 relapses, in all these cases relapse was accompanied or announced by conversion to positive TRAK values. The high sensitivity and specificity of the assay (in a control group of 40 patients with autonomous adenoma no positive TRAK was seen) allow to use the test for discrimination between Graves' disease and disseminated autonomy of the thyroid in patients presenting with diffuse hyperthyroidism. Thus, by helping to establish an exact diagnosis, TRAK could become important for therapy planning. Concerning relapse prediction, our data are less promising since only 39% of patients with persistently positive TRAK titers relapsed. TRAK is not a reliable indicator of relapse risk especially in patients operated or treated with radioiodine. On the other hand, 10% of patients showing negative titers after treatment also relapsed, all turning to positive TRAK values at the same time.

Autoantibodies↗
PubMed1978

The AC impedance of Necturus gallbladder epithelium.

The impedance of Necturus gallbladder epithelium was determined using sine wave currents of 1 Hz to 30 kHz. In control Ringer's solution the impedance locus exhibited a simple semicircle with minute shift of the high frequency end along the real axis and a minute depression of the center below the real axis (average 0.9 +/- 0.7 degrees). Neglecting the slight suppression, the impedance of 1 cm2 of epithelium can be represented by an electrical analogue consisting of a parallel RC element of 115 +/- 26 omega and 5.16 +/- 0.9 muF in series with a small resistor of 5.3 +/- 1.3 omega. In agreement with experimental results obtained under ionic or osmotic substitutions, the applicability of this simple RC analogue to gallbladder epithelium under control conditions can be explained by the influence of the paracellular shunt and by assuming the time constants of the apical and basal cell membranes to be comparable. Based on these data and on voltage divider measurements obtained with microelectrodes the capacitances of the apical and basal cell membrane can be estimated to be approximately 7 and approximately 18 muF/cm2. The latter value agrees well with estimates of the surface folding obtained from electromicrographs, if the specific cell membrane capacitance is assumed to be approximately 1 muF/cm2 as in other cell membranes.

Animals↗