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C Szliska

Publications and source records attributed to C Szliska.

11 recordsLinked to original sources

Homozygous gene deletions of the glutathione S-transferases M1 and T1 are associated with thimerosal sensitization.

OBJECTIVE: Thimerosal is an important preservative in vaccines and ophthalmologic preparations. The substance is known to be a type IV sensitizing agent. High sensitization rates were observed in contact-allergic patients and in health care workers who had been exposed to thimerosal-preserved vaccines. There is evidence for the involvement of the glutathione system in the metabolism of thimerosal or its decomposition products (organomercury alkyl compounds). Thus detoxification by polymorphically expressed glutathione S-transferases such as GSTT1 and GSTM1 might have a protective effect against sensitization by these substances. METHODS: To address this question, a case control study was conducted, including 91 Central European individuals with a positive patch-test reaction to thimerosal. This population was compared with 169 healthy controls and additionally with 114 individuals affected by an allergy against para-substituted aryl compounds. The latter population was included in order to test whether possible associations were due to substance-specific effects, or were a general feature connected with type IV immunological diseases. Homozygous deletions of GSTT1 and GSTM1 were determined by polymerase chain reaction. RESULTS: Glutathione S-transferase M1 deficiency was significantly more frequent among patients sensitized to thimerosal (65.9%, P = 0.013) compared with the healthy control group (49.1%) and the "para-compound" group (48%, P = 0.034). Glutathione S-transferase T1 deficiency in the thimerosal/mercury group (19.8%) was barely elevated versus healthy controls (16.0%) and the "para-compound" group (14.0%). The combined deletion (GSTT1-/GSTM1-) was markedly more frequent among thimerosal-sensitized patients than in healthy controls (17.6% vs. 6.5%, P = 0.0093) and in the "para-compound" group (17.6% vs. 6.1%, P =0.014), revealing a synergistic effect of these enzyme deficiencies (healthy controls vs. thimerosal GSTM1 negative individuals, OR = 2.0 [CI = 1.2-3.4], GSTT1-, OR = 1.2 [CI = 0.70-2.1], GSTM1/T1-, OR = 3.1 [CI = 1.4-6.5]). CONCLUSIONS: Since the glutathione-dependent system was repeatedly shown to be involved in the metabolism of thimerosal decomposition products, the observed association may be of functional relevance.

Adolescent↗

Genotype and phenotype of N-acetyltransferase 2 (NAT2) polymorphism in patients with contact allergy.

We investigated whether patients with contact allergy differed from non-contact-allergic, non-atopic controls with regard to genotype and phenotype of the polymorphic enzyme N-acetyltransferase 2 (NAT2). 55 contact-allergic patients recruited from the Information Network of Departments of Dermatology (IVDK) were compared to 85 controls from among local health care personnel. NAT2 activity was calculated from HPLC analysis of the ratio of the caffeine metabolites 5-acetylamino-6-formylamino-3-methyluracil (AFMU) and 1-methylxanthine (1MX) in the urine. NAT2 genotype was determined by polymerase chain reaction (PCR). A statistically significantly increased proportion of rapid acetylators was found in contact-allergic patients. This may have 2 possible implications: acetylation may enhance contact sensitization; or NAT2 status may be a genetic marker for contact sensitizability.

Acetylation↗

More positive patch test reactions with larger test chambers? Results from a study group of the German Contact Dermatitis Research Group (DKG).

Test chambers of various sizes are commercially available for patch testing. Therefore, we asked the question whether the size of patch test chambers may affect allergic patch test reactions. A total of 495 patients were double tested synchronously with small and large Finn Chambers containing standard preparations of fragrance mix, wool wax alcohols, Kathon CG and formaldehyde. Double tests in 217 patients who had reacted with at least 1 allergic, questionable, or irritant reaction to 1 of these allergens were statistically evaluated. For each of the 4 allergens, a significantly higher number of stronger reactions was seen with the large chambers as compared to the small ones. It is concluded that large test chambers may be useful for detection of weak sensitizations to particular contact allergens.

Adult↗

Common allergenic structures in hazelnut, rye grain, sesame seeds, kiwi, and poppy seeds.

Allergy to kiwi, poppy seeds, and/or sesame seeds often occurs in patients with a simultaneous sensitization to nuts and flour. Previously cross reactions have been verified by RAST inhibition. In this study the nature of this cross-reactivity is further characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by immunoblotting to nitrocellulose. The degree of cross-reactivity among kiwi, sesame seeds, poppy seeds, hazelnuts, and rye grain was found to be very high in the patients studied. The existence of both cross-reacting and unique components was observed; however, the cross-reacting and unique components could be different for different patients.

Adolescent↗

Patch testing with amalgam at various concentrations.

27 patients with positive D3 reactions on patch testing to 3 mercury screening allergens were patch tested with 13 mercury patch test preparations, 6 inorganic and 7 organic, and amalgam 20% pet. The 13 patients (all women) showing positive reactions to 20% amalgam were then patch tested to reducing concentrations. 2 patients reacted down to 1%, 4 down to 2%, 4 down to 5%, 2 down to 10% and 1 only to 20%, a total of 10 of the 13 patients therefore reacting to the 5% concentration of amalgam. The appropriate patch test concentration of amalgam is discussed and the clinical significance and female preponderance of amalgam reactivity suggested as being worthy of further investigation.

Adolescent↗

[Reproducibility of epicutaneous test results].

857 non-dermatologic patients were patch-tested with the Finn-Chamber-technique. The sequent testings under identical conditions were made after 3-12 months. Readings were done after 24, 72, 96 hours and later. During the first test-series we found 44 reactions to be positive, 20 remained identical during repetition-testings, 7 became negative and 36 positive reactions appeared. So reproducibility was 46% for the positive results of the first testing serie.

Allergens↗