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F J Wiedermann

Publications and source records attributed to F J Wiedermann.

23 records · Page 2Linked to original sources
PubMed1993

Induction of normal human eosinophil migration in vitro by substance P.

To investigate the role of tachykinins in allergic inflammation, the effect of substance P (SP) on normal human eosinophil migration was examined in Boyden chamber type assays. SP stimulated eosinophil migration in vitro with an EC50 of about 1-10 pM and maximal effects were seen at 100 pM. A carboxy-terminal fragment of SP possessed appreciable activity whereas an amino-terminal fragment was inactive. Data represented in this paper and previous studies suggest that eosinophils are attracted by SP and activated to enhanced mediator release and cytotoxic activity.

Chemotaxis, Leukocyte↗
PubMed1991

Suppression of thyroid function by interferon-alpha 2 in man.

Profound biological changes occur in patients treated with interferon. Observations of endocrine changes prompted us to examine the effects of subcutaneous alpha-interferon administration in single doses on circulating levels of thyroid stimulating hormone, total thyroxine, and total triiodothyronine in 10 volunteers (5 healthy subjects and 5 patients with hepatitis C). Blood samples were taken on an out-patient basis immediately before and 2, 12, 24, 48, and 72 h after administration of 1, 3, or 5 x 10(6) units of recombinant alpha-interferon. Application of the different dose levels was randomly assigned. Plasma samples were stored at -80 degrees C; after collection of samples had been completed hormone levels were measured using commercially available test kits. At all time points before and after injection of alpha-interferon, standard deviations of measured hormone levels of healthy control subjects and patients overlapped to a considerable extent. At a dose level of 5 x 10(6) units, alpha-interferon significantly increased cortisol levels as described, and decreased the level of thyroid stimulating hormone in the group receiving alpha-interferon as compared to placebo-treated healthy volunteers. The effects occurred 12 h after injection. Maximum suppression of thyroid stimulating hormone levels was observed 24 h after injection, when serum levels of thyroxine and triiodothyronine also were significantly reduced. We conclude that subcutaneous alpha-interferon treatment with doses as low as 5 x 10(6) units affects the control of thyroid function.

Adult↗
PubMed1989

In vitro human polymorphonuclear leukocyte chemokinesis and human monocyte chemotaxis are different activities of aminoterminal and carboxyterminal substance P.

Polymorphonuclear leukocytes (PMNL) are a component of the inflammatory response to neurogenic mediators. Using the micropore filter approach, the authors studied the chemoattracting properties of tachykinins, including substance P (SP), neurokinin A (NKA) and neurokinin B (NKB), and that of calcitonin gene-related peptide (CGRP) for human PMNL in vitro and now show that SP in near nanomolar concentrations stimulates locomotion of human PMNL. Locomotion of PMNL is induced by SP, aminoterminal SP (1-9) and the SP receptor antagonist [D-pro2, D-trp7,9]-SP (DPDT) but not by carboxyterminal SP (3-11), NKA, NKB, or CGRP suggesting that the aminoterminal amino acids arginine and proline are essential residues of SP in activation of PMNL locomotion. In contrast, the migratory effect of SP on monocytes resides in the carboxyterminal SP amino acid sequence, which is in agreement with carboxyterminal, SP receptor-mediated chemotaxis of human monocytes previously shown by others. From the known structure-activity relationships for SP receptors it is concluded that induction of PMNL migration by SP does not involve neurokinin-1 (NK-1), NK-2 or NK-3 receptors. "Checkerboard" analysis reveals that PMNL locomotion by SP is not dependent on concentration gradients and thus represents chemokinesis, which is enhancement of speed and/or frequency of locomotion. One cannot exclude that this action of SP on PMNL is mediated by the aminoterminal sequence via yet unknown SP "receptors".(ABSTRACT TRUNCATED AT 250 WORDS)

Calcitonin Gene-Related Peptide↗