Search PubMed⌕ Search

Biomedical subjects

C Kroegel

Publications and source records attributed to C Kroegel.

At least 127 records · Page 7Linked to original sources

[Systemic necrotizing vasculitis with bronchial asthma and eosinophilia: Churg-Strauss syndrome].

Two cases of the Churg-Strauss syndrome are reported, seen within the past year. The first concerned a 31-year-old woman with a rapidly progressive illness characterized by bronchial asthma, leukocytosis and eosinophilia, abdominal pain, diarrhoea and purpura. In the second case, a 47-year-old man had granulomatous epididymitis and interstitial nephritis before the asthma and eosinophilia developed. In both the diagnosis was confirmed by lung biopsy. Immunosuppressive treatment achieved rapid regression of all symptoms and of the eosinophilia, without recurrence so far.

Adult↗

Platelet-activating factor induces eosinophil peroxidase release from purified human eosinophils.

The degranulation response of purified human eosinophils to platelet-activating factor (PAF) has been studied. PAF induced release of eosinophil peroxidase (EPO) and beta-glucuronidase from highly purified human eosinophils with an EC50 of 0.9 nM. The order of release was comparable with that induced by phorbol myristate acetate (PMA). The new specific PAF antagonist 3-[4-(2-chlorophenyl)-9-methyl-H-thieno[3,2-f] [1,2,4]triazolo-[4,3a][1,4]-diazepin-2-yl](4-morpholinyl)- 1-propane-one (WEB 2086) inhibited the PAF-induced enzyme release by human eosinophils in a dose-dependent manner. The viability of eosinophils were unaffected both by PAF and WEB 2086. The results suggest that PAF may amplify allergic and inflammatory reactions by release of preformed proteins from eosinophil granules.

Azepines↗

Demonstration of antibodies to the surface (anti-p41) and core proteins (anti-p24) of the human immunodeficiency virus (HIV) in individuals positive for anti-HIV.

Diagnosis of infection with the human immunodeficiency virus (HIV) relies on the demonstration of antibody to this virus. Occasionally, the combined analysis of sera using ELISA and western blot reveals false-positive results. We have compared a newly developed test to detect antibodies to the core (anti-p24) and surface (anti-p41) proteins of HIV with the established tests described above. Anti-p24 and anti-p41 were negative in three individuals positive for anti-HIV by ELISA and immunoblot; they had a low risk to acquire HIV infection and were clinically and immunologically normal and suspected false positive previously. In 62 individuals at risk, anti-p41 was always positive while anti-p24 was negative in 24/62 individuals including all but one patient with AIDS. The data indicate that this new test may replace the western blot as a reliable, widely available, and standardized confirmatory assay. In addition, preliminary evidence needs to be confirmed that quantitative analysis of anti-p24 might be of prognostic value in the course of HIV infection.

Acquired Immunodeficiency Syndrome↗

Modulation of the eosinophil chemotactic factor (ECF) release from various cells and their subcellular components by phospholipids.

An eosinophil chemotactic factor (ECF) can be released from human polymorphonuclear neutrophils (PMN), rat mononuclear and rat mast cells by the calcium ionophore (A23187), during phagocytosis, by arachidonic acid and phospholipase A2. It has been suggested that stimuli such as the ionophore and the phagocytic event lead to phospholipid turnover with the generation of arachidonic acid which is subsequently transformed by a lipoxygenase-like enzyme into ECF. Addition of phospholipids such as phosphatidylethanolamine and phosphatidylinositol during ionophore stimulation of various cells increased the ECF release significantly. ECF activity is also enhanced in the presence of indomethacin at concentrations which inhibit prostaglandin synthesis. With bromphenylacylbromide and eicosatetraynoic acid, ECF generation as well as the chemotaxis of eosinophils is inhibited suggesting that the phospholipase A2-arachidonic acid pathway represents a common link for ECF release as well as for the chemotaxis of eosinophils. From the cytosol of human PMN an ECF-containing enzyme was obtained. Incubation of phospholipase A2 and phospholipids with the ECF-converting enzyme led to potent ECF indicating that addition of phospholipids provides the soluble ECF-generating system with an additional source of arachidonic acid. The data represent a molecular approach to analyze the mechanisms of ECF release from soluble components after immunological triggering of the cells.

Animals↗

Role of the eosinophil in protein oxidation in asthma: possible effects on proteinase/antiproteinase balance.

BACKGROUND: Many of the leukocytes which migrate into the tissue following allergen challenge can undergo a respiratory burst producing reactive oxygen species causing tissue damage and distorting proteinase/antiproteinase balance. The reactive oxygen species have extremely short half lives and so cannot be measured in vivo, but the protein carbonyl residues which result from protein oxidation can be measured in biological fluids. METHODS: We examined protein oxidation in bronchoalveolar lavage after allergen challenge in 12 patients with atopic asthma by measuring protein carbonyl residues using a sensitive Western blotting technique. RESULTS: We found that the median level of protein carbonyls per molecule of protein rose from 0.09 in bronchoalveolar lavage (BAL) obtained 18 h after saline challenge to 0.23 in BAL taken 10 min after segmental allergen challenge, reaching a median of 0.82 in samples obtained 18 h later (p<0.01 compared with saline control and the earlier time point). The number of protein carbonyl residues correlated strongly with the number of eosinophils recovered in the BAL (rho = 0.574, p<0.05) but not with the number of neutrophils (rho = 0.228, p = NS) or macrophages (rho = 0.178, p = NS). Western blotting showed that the majority of the modified protein comigrated with authentic alpha1-antitrypsin at 53 kD. In contrast, BAL samples from patients with chronic obstructive pulmonary disease, which is characterized by an influx of neutrophils, showed that the main oxidized protein colocalized with human serum albumin, the predominant protein in the BAL. CONCLUSION: Our results suggest that the recruitment and activation of eosinophils accounts for much of the protein oxidation found in the BAL following allergen challenge. The main oxidized protein appears to be alpha1-antitrypsin, a key antiproteinase in the airways. Inactivation of alpha1-antitrypsin by oxidation may distort the proteinase/antiproteinase balance leaving the lung vunerable to proteolytic damage. Intriguingly, we have evidence to suggest that other airways diseases, characterized by recruitment of other inflammatory cells, may result in the oxidation of alternative targets.

Adult↗