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Serial Concentrations (serial + concentration)
Selected AbstractsFlow cytometry versus histamine release analysis of in vitro basophil degranulation in allergy to Hymenoptera venomCYTOMETRY, Issue 1 2003C. Lambert Abstract Background Flow cytometry (FCM) has been proposed for specific allergy in vitro testing. We investigated its biological significance for allergy to Hymenoptera venoms and compared it with the routinely performed basophil histamine release test (HRT). Methods Blood samples from 26 allergic and 8 nonallergic donors were incubated with venom at serial concentrations. Basophils were analyzed with anti-CD45-PE-Cyanin 5, Anti-IgE-FITC, and Anti-CD63-Phycoerythrine. HRT was measured by radioimmunoassay. Results FCM was as convenient as HRT for measuring basophil reactivity in at least 87% of allergic and 75% of nonallergic subjects. CD63 outer expression was specifically induced in 91% of releaser subjects (86% on HRT) and in 1 of 10 tests in nonallergic donors, or one of six tests (16% on HRT) in allergic patients tested with an irrelevant allergen. Both methods were concordant in 85.7% of the tests. The three discordant patients had low-grade reactions and borderline biological responses on FCM (n = 2) or HRT (n = 1). Conclusions The dynamic, physiologic significance of CD63, the dose,response curve, and dependency on ethylene-diaminetetra acetic acid suggested that both tests reflect the same mechanism. Cytometry Part B (Clin. Cytometry) 52B:13,19, 2003. © 2003 Wiley-Liss, Inc. [source] Serum S-100 Protein Is Not a Suitable Seizure Marker in Temporal Lobe EpilepsyEPILEPSIA, Issue 10 2002Fritz Leutmezer Summary: ,Purpose: S-100 protein is a sensitive marker of various brain diseases; however, its role in epilepsy is controversially discussed in the literature. We therefore studied the temporal profile of serial concentrations of S-100 protein in serum after secondarily generalized tonic,clonic seizures during video-EEG monitoring. Methods: Ten patients with mesial temporal lobe epilepsy were prospectively studied. Serum S-100 protein was measured after a seizure-free period of ,24 h (baseline) and 30 min, 3, 6, 12, and 24 h after a secondarily generalized tonic,clonic seizure of temporal lobe origin in nine and a convulsive status epilepticus in one patient. Results: All S-100 levels were within the normal range, except for those of one patient at baseline. Mean values were 0.045 ,g/L (range, 0.003,0.13 ,g/L) at baseline, 0.038 ,g/L (range, 0.003,0.09 ,g/L) at 30 min, 0.036 ,g/L (range, 0.003,0.08 ,g/L) at 3 h, 0.034 ,g/L (range, 0.003,0.07 ,g/L) at 6 h, 0.034 ,g/L (range, 0.003,0.08 ,g/L) at 12 h, and 0.035 ,g/L (range, 0.003,0.09 ,g/L) at 24 h after seizure offset. There were no significant differences between mean concentrations at any interval postictally. Conclusions: We could not detect any significant alterations in serum S-100 protein concentration either after a single secondarily generalized tonic,clonic seizure or after convulsive status epilepticus in patients with temporal lobe epilepsy. Our data do not confirm previous work, which suggested serum S-100 protein to be a suitable marker for epileptic seizures. [source] Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and ItalyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2003Roberto Ronchetti Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals ,,3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98,2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97,3.80) and by D. farinae (OR 3.15; CI 1.16,8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian,Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions. [source] Decreased expression of heparin-binding epidermal growth factor,like growth factor as a newly identified pathogenic mechanism of antiphospholipid-mediated defective placentationARTHRITIS & RHEUMATISM, Issue 5 2010N. Di Simone Objective Heparin-binding epidermal growth factor,like growth factor (HB-EGF) plays a role in blastocyst implantation and is down-regulated in preeclampsia and in hypertensive pregnancy disorders associated with defective extravillous trophoblast invasion. Defective placentation and severe preeclampsia are also features of the antiphospholipid syndrome (APS). The purpose of this study was to investigate whether abnormal HB-EGF expression plays a pathogenic role in antiphospholipid antibody (aPL),mediated defective placentation. Methods HB-EGF expression in placental tissue was evaluated by Western blotting and messenger RNA analysis in normal and APS placentae. Polyclonal IgG fractions or monoclonal ,2 -glycoprotein I,dependent aPL and their respective controls were investigated for the following 4 features: their binding to human trophoblast monolayers, as determined by cell enzyme-linked immunosorbent assay (ELISA); their effect on HB-EGF expression by Western blotting in trophoblast cell extracts as well as by ELISA as a protein secreted in the culture supernatants; their inhibitory effect on in vitro trophoblast invasiveness, as evaluated by Matrigel assay; and their inhibitory effect on matrix metalloproteinase (MMP) levels, as measured by gelatin zymography. Experiments were also performed in the presence of serial concentrations of heparin or recombinant HB-EGF. Results Placental APS tissue displayed reduced expression of HB-EGF. Polyclonal and monoclonal aPL bound to trophoblast monolayers and significantly reduced the in vitro synthesis and secretion of HB-EGF. Heparin inhibited aPL binding and restored HB-EGF expression in a dose-dependent manner. Addition of recombinant HB-EGF reduced the in vitro aPL-induced inhibition of Matrigel invasiveness as well as MMP-2 levels. Conclusion These preliminary findings suggest that the reduction of aPL-mediated HB-EGF represents an additional mechanism that is responsible for the defective placentation associated with APS and that heparin protects from aPL-induced damage by inhibiting antibody binding. [source] | ||||||||||