Superoxide production by phagocytic leukocytes: transmembrane signalling and potential interactions of the second messengers in cell stimulation.
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Animals↗
Biomedical subjects
W Horn
Publications and source records attributed to W Horn.
[Resorption of progesterone through the intact skin of the breast in comparison with other body regions].
In healthy female volunteers the percutaneous absorption of progesterone from an ointment is studied comparing the absorption in the breast skin and that of other regions (thigh, abdomen). Before and certain times after the application progesterone serum levels are measured. A significant increase of mean serum levels (1 to 1.9 ng/ml) ist observed after application to the breast, while it is missing after application to other sites. Individual values of progesterone levels show a distinct peak after 30-120 min following application to the breast, while it lacks in three cases following other application. Serum peaks do not depend on the skin thickness as determined by ultrasound measurement. Percutaneous treatment with progesterone obviously is easier to perform using the breast skin than that of other regions.
Administration, Topical↗
Features of the translocation of protein kinase C in neutrophils stimulated with the chemotactic peptide f-Met-Leu-Phe.
The effects of f-Met-Leu-Phe (fMLP) on neutrophils, i.e. elevation of the levels of cytoplasmic Ca2+ and intramembranous diacylglycerol, would be expected to be accompanied by translocation of protein kinase C (PKC) to the plasmalemma. However, fMLP-induced PKC translocation could hitherto be demonstrated only when cells were additionally treated with cytochalasin B. We show here that treatment of guinea pig neutrophils with fMLP alone does lead to a significant PKC translocation which can be inhibited by pertussis toxin. The translocation can be detected only if the incubation is terminated within 30 sec after addition of fMLP, the termination is rapid, e.g. by application of a freeze clamp-technique, and the concentration of Ca2+ chelators in the buffer used for lysing the cells is low.
Animals↗
all-trans-Retinal stimulates superoxide release and phospholipase C activity in neutrophils without significantly blocking protein kinase C.
all-trans-Retinal was previously shown to stimulate high levels of superoxide release by guinea pig neutrophils. When the cells, previously labeled with [3H]inositol, are treated with all-trans-retinal, they exhibit a decrease in the levels of [3H]inositol phospholipids and an increase in the accumulation of [3H]inositol phosphates. The maximal accumulation of inositol phosphates and the optimal rate of superoxide release occurred together at approximately 7 min after stimulation. The levels of [3H]inositol phosphates accumulated were comparable to those observed when the cells were stimulated with a chemotactic peptide. In direct measurements, using concentrations that stimulate intact cells maximally, all-trans-retinal was found not to inhibit protein kinase C from the cytosol of neutrophils significantly. This contrasts with the situation with this kinase obtained from other sources. These observations represent additional effects of vitamin A on cells.
Free Radicals↗
An improved fluorochrome microassay for the detection of living and non-living intracellular bacteria in human neutrophils.
Acridine orange fluorescence may be used to distinguish living from non-living intracellular bacteria in individual glass-adherent neutrophil granulocytes (PMN). An improvement of the original assay (Smith and Rommel, 1977; Pantazis and Kniker, 1979) is described which allows differentiation between ingested and cell-adherent bacteria. It is shown that this differentiation is impossible with the original method using wet-mounted preparations. With the improved method, however, using dry-mounted preparations, cell-adherent as well as extracellular bacteria lose their fluorescence. Moreover, the fluorescence of cell nuclei and granula is reduced to a minimum. Phagocytosis kinetics and selective inhibition of the myeloperoxidase of PMN show that living intracellular bacteria fluoresce green and non-living bacteria red in such dry-mounted preparations. The preparations can be stored and interpreted for at least 2 months. Application of this method requires 0.1 ml blood or cell-rich body fluid per preparation and is fast and inexpensive.
Acridine Orange↗
Effect of phorone-induced glutathione depletion on the metabolism and hepatotoxicity of carbon tetrachloride and vinylidene chloride in rats.
Although the depletion of hepatic glutathione in male rats following treatment with phorone (diisopropylidene acetone) did not affect the xenobiotic-metabolizing microsomal enzyme system, the metabolic elimination of vinylidene chloride (VDC) from the atmosphere of a closed exposure system was inhibited. However, the hepatotoxicity of VDC was enhanced after GSH-depletion, although no enhancement of VDC-induced in vivo lipid peroxidation was observed. In contrast, GSH depletion had no influence on the metabolic elimination of carbon tetrachloride, but augmented both the hepatotoxic response to and the in vivo lipid peroxidation induced by CCl4. In the case of VDC GSH-depletion hepatoxicity was increased because of a change in the metabolic pathway, resulting in production of intermediates of greater toxicity: lack of GSH in CCl4 treated rats renders membrane phospholipids more susceptible to peroxidative damage.
Animals↗
Effect of hypoxia on the metabolism and hepatotoxicity of carbon tetrachloride and vinylidene chloride in rats.
The metabolism of vinylidene chloride (VDC) and carbon tetrachloride (CCl4) was investigated by measuring the removal of the compounds from the atmosphere of a closed exposure system occupied with male rats. Hepatotoxicity was evidenced in the same rats by determining serum enzyme activities of the aminotransferases (GOT, GPT) and sorbitol dehydrogenase (SDH) before, at the end of the exposure time and 24 hrs later. Control rats exposed to VDC concentrations up to 2000 p.p.m. showed only slight increases of serum aminotransferase- and SDH-activities, which were not at all observed under hypoxic conditions. Hypoxia evoked a small, but significant reduction of the VDC metabolism at 500 p.p.m., but not at 2000 p.p.m. exposure concentration. In contrast to VDC CCl4-metabolism (150 p.p.m.) was increased under hypoxia and consequently hepatotoxicity was aggravated.
Animals↗
[Follow-up of patients with differentiated thyroid cancer: determination of serum thyroglobulin in place of routine 131I scintigraphy?].
A comparison was conducted in patients with differentiated thyroid carcinoma still under 131I therapy (n = 18) between 2 mCi-131I scans, posttherapeutic scans and radioimmunologically measurable serum thyroglobulin (TG). All 3 parameters were positive in only 9 cases; among the other 9 patients TG appeared to be the better indicator (ratio 5:1) of residual tumour tissue than the 2 mCi-131I scan. In a second group of patients who had completed 131I therapy the 2 mCi scan and TG were compared (n = 21). Both indices were negative in 15 cases, whereas TG was positive in 6 patients in spite of a negative scan. TG generally remained within the clearly positive range also during T4 therapy. TG was highest in metastatic disease and practically uninfluenced by T4, i.e. by the endogenous TSH level. TG antibodies were found in 15% of cases, generally with low titres only; this did not interfere with TG determination as tumour marker. In summary, TG measurement appears to be superior to 2 mCi-131I scans for follow-up of cases with differentiated thyroid carcinoma.
Humans↗
[Current theories of phagocytosis and methodological problems in the study of phagocytosis defects in diabetics].
The process of phagocytosis on bacteria is described: recognition of the bacterium by C3b- and Fc-receptors and possibly lektin-like substances on PMN surfaces; ingestion by an actin-myosin interaction in a local Ca++ gradient; simultaneous activation of a NADPH-oxidase and oxidative attack of the bacterial membrane. Special aspects: opsonization, dependence of the rate of phagocytosis on day-time, conditions of diabetics.
Actins↗
[Measurement of thyroglobulin or 131iodine scintigraphy in the after-care of patients with differentiated thyroid cancer].
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Aftercare↗
[Effects of tattoo removal and results after salabrasion].
22 patients have been treated with a three minutes salabrasion, once for repeatedly, on skin areas around 41 tattoos. Following long-term results could be established with tattoos performed by laymen on forearm, upper arm or posterior, a single salabrasion produced perfectly acceptable to good results in the removal of tattoos. As to be expected, repeated salabrasion and additional skin surgery improved the results in removing tattoos. Frequently, single or repeated salabrasion resulted in hypopigmentation of the interfollicular epidermis with a more or less intensive skin-colored to brownish pigmentation of the follicle regions. The general impression of hyperpigmentation only occurred occasionally after single salabrasion and was independent of location. Single or repeated salabrasion resulted in an emphasis of the surface structure and increased wrinkling of the skin in due course, but never in scar formation.
Adolescent↗
[Significance of thyroglobulin as a tumor marker in the serum of patients with differentiated thyroid carcinoma: longitudinal and cross-sectional studies (author's transl)].
For evaluating the clinical significance of thyroglobulin measurements for the follow-up of patients with differentiated thyroid carcinoma, thyroglobulin was determined radioimmunologically during the past 2 years (up to 12 times) in 40 patients after withdrawal of thyroid hormone. Thyroglobulin values were compared with whole-body scintigrams after radioiodine. Thyroglobulin antibodies, which may interfere in the radioimmunoassay for thyroglobulin, were also estimated by a radioimmunologic method. In the majority of cases, thyroglobulin levels corresponded to the scintigrams, however, the thyroglobulin level appeared to be a more precise index for changes in tumor tissue mass. In one patient the scintigram was negative, whereas considerable amounts of thyroglobulin were measured in the serum: X-ray tomography revealed a lung metastase in this case. On the other hand, thyroglobulin was undetectable in the sera of patients who exhibited distinct metastases in the scintigram. Thyroglobulin can be regarded as a tumor marker in patients thyroidectomized for differentiated thyroid carcinoma. However, its determination can certainly not replace whole-body scintigraphy as postulated by several authors, although thyroglobulin measurement appears to be superior to scanning in some cases. A combined application of iodine scanning and thyroglobulin radioimmunoassay is thus advisable in the follow-up of patients with differentiated thyroid carcinoma.
Antibodies↗
Suppression of the anti-erythrocyte immune response in mice by the C5b--9 complex of complement.
The C5b--9 complex of complement associated with sheep erythrocyte membranes suppresses the immune response of mice to sheep erythrocytes as measured with the Jerne plaque technique. This type of immune suppression is independent of early complement components and antibody, and is mediated by both human and guinea-pig complement components. The degree of immune suppression correlates with the number of C5b--9 complexes per cell used for immunization: 21,000 C5b--9 complexes per erythrocyte lead to a 97% inhibition of the immune response in comparison to untreated erythrocytes. Inhibition requires the full assembly of the C5b--9 complex including C8 and C9. Virtually no inhibition was observed by the C5b--7 complex. C5b--9 and IgG-mediated immune suppression do not function additively. From dose-response experiments it is concluded that separate and mutually independent sites mediate suppression by C5b--9 and IgG, respectively.
Animals↗
On the long-term behavior of grafts of meshed skin.
In the past four years, 47 patients in our institution had grafts of meshed skin placed on a variety of defects. Indications, advantages and disadvantages, and postoperative phenomena are presented. Ten cases were available for a follow-up study of one to four years. Subjective complaints in the graft sites; vulnerability of the grafts to ordinary trauma; the patient's opinion of the postoperative condition; visibility of the mesh pattern; level; hyper- or hypopigmentation of the grafted sites; occurrence of hypertrophic scars or keloids; return of sensations (touch, pressure, cold, warmth, and epicritic pain); and thermographic findings in the graft sites were inquired about and judged objectively.
Adolescent↗
[Melanosis striata longitudinalis ungium].
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Female↗
[On the physiology of the growth of nail plate (author's transl)].
By following up histologically a localized storage of melanin in certain layers of the nail plate the differing theories on the cellular kinetics of the growth of human nail plate are checked up. Thus it turns out that the hitherto existing and even contradicting conceptions are not helpful to interpret uniquely the morphological phenomena of the concrete case. A plausible modification is presented.
Humans↗
Modulation of the immune response by pretreatment of antigen with complement.
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Animals↗
Peritoneal exudate T lymphocytes with specificity to sheep red blood cells. II. Inflammatory helper T cells and effector T cells in mice with delayed-type hypersensitivity and in suppressed mice.
Peritoneal exudate cells were induced in mice 4 days after immunization with SRBC. A low dose of SRBC (10(6) i.v.) caused T lymphocytes to appear in inflammatory exudates. These cells, not only transferred DTH reactions, but also functioned as helper T cells in antibody production after transfer to syngeneic nu/nu recipient mice. After a high dose of SRBC (10(9) i.v.), very few helper T cells and no DTH transferring T cells were found in inflammatory exudates, although they were present in the spleen. It is postulated that T cells mediating DTH reactions and helper T cells behave similarly as far as those dose dependency of appearance in inflammatory exudates is concerned. A high dose of sensitizing antigen causes retention of helper and effector T cells in the spleen, in this way favouring antibody formation; low doses of antigen allow them to leave the spleen, thus favouring mediation of DTH reactions in the periphery.
Animals↗