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Biomedical subjects

M Bruze

Publications and source records attributed to M Bruze.

At least 55 records · Page 3Linked to original sources
PubMed2001

Health effects of occupational exposure to acrylamide using hemoglobin adducts as biomarkers of internal dose.

OBJECTIVES: This study assessed the health effects of occupational acrylamide exposure using hemoglobin (Hb) adducts as biomarkers of internal dose. METHODS: Two hundred and ten tunnel workers exposed for about 2 months to a chemical-grouting agent containing acrylamide and N-methylolacrylamide underwent a health examination. Blood samples were drawn for the analysis of Hb adducts of acrylamide. Fifty workers claiming recently developed or deteriorated symptoms of the peripheral nervous system (PNS) were referred to a neurophysiological examination. Workers with Hb-adduct levels exceeding 0.3 nmol/g globin attended follow-up examinations 6, 12, and 18 months after exposure cessation. RESULTS: Forty-seven workers had Hb-adduct levels within the normal background range (0.02-0.07 nmol/g globin), while the remaining 163 had increased levels up to a maximum of 17.7 nmol/g globin. Clear-cut dose-response associations were found between the Hb-adduct levels and PNS symptoms. Thirty-nine percent of those with Hb-adduct levels exceeding 1 nmol/g globin experienced tingling or numbness in their hands or feet. A no-observed adverse effect level of 0.51 nmol/g globin was estimated for numbness or tingling in the feet or legs. For 23 workers there was strong evidence of PNS impairment due to occupational exposure to acrylamide. All but two had recovered 18 months after the cessation of exposure. CONCLUSIONS: Occupational exposure to a grouting agent containing acrylamide resulted in PNS symptoms and signs. The use of Hb adducts of acrylamide as a biomarker of internal dose revealed strong dose-response associations. The PNS symptoms were, however, generally mild, and in almost all cases they were reversible.

Acrylamide↗
PubMed2001

Patch testing with serial dilutions of budesonide, its R and S diastereomers, and potentially cross-reacting substances.

BACKGROUND: Budesonide, a marker for corticosteroid allergy, is a 1:1 mixture of 2 diastereomers, the R and S, present in all commercial formulations. Budesonide is said to cross-react with group B substances through the R and S diastereomer and some group D substances only through the S diastereomer. OBJECTIVE: To investigate the cross-reactivity pattern between the R and S diastereomers and 4 potentially cross-reacting substances, 2 from group B and 2 from group D. METHODS: By patch testing 10 patients hypersensitive to budesonide with a serial dilution of budesonide, the R and S diastereomer, triamcinolone acetonide, amcinonide, prednicarbate, and hydrocortisone-17-butyrate. RESULTS: Nine of 10 patients reacted to budesonide and the S diastereomer. Seven of 9 to the R diastereomer. Each of the 9 patients with S diastereomer allergy reacted to the group B and/or group D substances. Five patients reacted to triamcinolone acetonide, not to 1.0% but only to 0.0010% and 0.00010%. CONCLUSION: The R and S diastereomers can induce positive patch test reactions in budesonide-hypersensitive individuals. The potential of budesonide to cross-react with substances from group B and D might be explained by the presence of the 2 diastereomers. When patch testing with triamcinolone acetonide, much lower concentrations than recommended should be used.

Allergens↗
PubMed2000

Patch testing with corticosteroid mixes in Europe. A multicentre study of the EECDRG.

This study investigated whether a corticosteroid mix containing tixocortol pivalate, budesonide, and hydrocortisone-17-butyrate could detect contact allergy to corticosteroids. 2 corticosteroid mixes, 1 with a high (mix I) and 1 with a low (mix II) concentration and the 3 individual constituents, each at 2 concentrations, were inserted into the standard series of 16 participating clinics. Tests were read on day (D) 3 or 4. 5432 patients were tested, and 110 (2.0%) had positive reactions to at least 1 of the 8 test preparations. Of the 8 preparations, mix I identified most allergic patients, followed by mix II, budesonide 0.10%, budesonide 0.002%, and tixocortol pivalate, both concentrations (1.0 and 0.10%) tracing the same number. With the mixes, 53.2-59.6% of tixocortol pivalate allergy was missed. 47 patients were allergic to either concentration of tixocortol pivalate, 25% of these only to 1.0% and another 25% only to 0.10%. Testing with mix I and tixocortol pivalate 0.10% picked up 98/110, testing with tixocortol pivalate 1.0% and 0.10% and budesonide 0.10% picked up 105/110. 3379 patients were read on both D3 or D4 as well as on D7. Without a late reading (D7), up to 30% of contact allergy to corticosteroid markers was missed.

Administration, Topical↗
PubMed2000

Stability of corticosteroid patch test preparations.

This study investigated the stability of tixocortol pivalate, budesonide, and hydrocortisone-17-butyrate (Hc-17-B) when present in a mix with petrolatum and when the corticosteroids were kept separately in petrolatum. The concentrations chosen for the corticosteroids were the same as those used in a study within the European Environmental Contact Dermatitis Research Group (EECDRG), in which 2 corticosteroid mixes (1 with a high concentration and 1 with a low concentration) and the 3 individual constituents, each at 2 concentrations, were patch tested. Ethanolic solutions of each corticosteroid, as well as 2 mixtures of these 3 corticosteroids, were also made up at corresponding concentrations. The preparations were kept at room temperature, refrigerated, and deep frozen, and repeatedly for 1 year, investigations to check stability by high performance liquid chromatography were carried out. A decrease of < or =20% of the initial value at time 0 was used as the threshold for stability. The petrolatum preparations and the ethanolic solutions of budesonide and tixocortol pivalate were stable for at least the whole investigative period, irrespective of storage conditions, while Hc-17-B 1.0% in ethanol kept deep frozen was stable at least during the same period. The latter corticosteroid when kept at room temperature was stable for 3 months only.

Administration, Topical↗
PubMed2000

Contact allergy to 5,5'-di-tert-butyl-2,2'-dihydroxy-(hydroxymethyl)-dibenzyl ethers, sensitizers, in p-tert-butylphenol-formaldehyde resin.

Allergy to p-tert-butylphenol-formaldehyde resin (PTBP-F-R) is not rare. This resin consists of a large number of substances, most of which are still unknown. More knowledge about the sensitizers in the resin is a good basis for development of diagnosis, treatment and prevention. The aim of this investigation was to study allergens in PTBP-F-R by isolation of some medium molecular weight substances from the resin and patch testing these in individuals hypersensitive to PTBP-F-R. 2 isolated substances were shown to be allergens in PTBP-F-R, 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-dihydroxymethyl-dibenzyl ether and 5,5'-di-tert-butyl-2,2'-dihydroxy-3-hydroxymethyl-dibenzyl ether. 13 patients hypersensitive to PTBP-F-R were patch tested with serial dilutions of 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-dihydroxymethyl-dibenzyl ether and 12 of them reacted positively. 12 patients hypersensitive to PTBP-F-R were patch tested with serial dilutions of 5,5'-di-tert-butyl-2,2'-dihydroxy-3-hydroxymethyl-dibenzyl ether and 11 of them reacted positively. Positive patch test reactions were seen down to 0.0000025 mmole x 1(-1) (approximately 0.01 ppm) for both 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-dihydroxymethyl-dibenzyl ether and 5,5'-di-tert-butyl-2,2'-dihydroxy-3-hydroxymethyl-dibenzyl ether in the most sensitive patient. HPLC analysis of 2 PTBP-F-Rs showed the presence of 1.0-1.7% w/w 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-dihydroxymethyl-dibenzyl ether and 0.75-0.90% w/w 5,5'-di-tert-butyl-2,2'-dihydroxy-3-hydroxymethyl-dibenzyl ether in the resins.

Allergens↗
PubMed2000

Sensitizing capacity of 5,5'-di-tert-butyl-2,2'-dihydorxy-(hydroxymethyl)-dibenzyl ethers in the guinea pig.

In patients hypersensitive to p-tert-butylphenol-formaldehyde resin (PTBP-F-R), it is for diagnostic, therapeutic and preventive reasons necessary to know the identity of the primary sensitizing substances, their sensitizing capacities as well as their cross-reaction patterns. We have recently shown that the 2 dimers in PTBP-F-R, 5,5'-di-tert-butyl-2,2'-dihydroxy-3-hydroxymethyl-dibenzyl ether (X) and 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-dihydroxymethyl-dibenzyl ether (IX) are contact sensitizers in man. The aim of this study was to investigate the sensitizing capacities of these dimers in PTBP-F-R and potential cross-reacting substances in the guinea pig with the guinea pig maximization test. IX, X, 2,6-dimethylol-p-tert-butylphenol (2,6-MPTBP), 2-methylol-p-tert-butylphenol (2-MPTBP), p-tert-butylcatechol (PTBC), 5,5'-di-tert-butyl-2,2'-dihydroxy-dibenzyl ether (XI) were used as possible cross reacting substances. IX and X were shown to be sensitizers. When compared to the sensitizers in phenol-formaldehyde resin, IX is a strong sensitizer (p= 0.00052) and X a moderate sensitizer (p=0.0053). Animals sensitized to IX showed cross-reactions to X (p=0.010), 2,6-MPTBP (p=0.0011) and PTBC (p=0.0498). Animals sensitized to X showed no cross-reactions to the substances that were tested. The results indicate that IX is a main allergen in PTBP-F-R, with possibly also X.

Allergens↗
PubMed2000

Exposure to metallic gold in patients with contact allergy to gold sodium thiosulfate.

Gold allergy is common, with approximately 10% of patients patch tested because of eczematous disease being positive to gold sodium thiosulfate (GSTS). However, clinical relevance seems to be rare. The aim of this prospective double-blind study was to demonstrate the effects of exposure to metallic gold, in this case earrings, in gold-positive patients. 60 female patients with pierced earlobes test-positive to GSTS were included in the study. The patients were randomized into 2 groups, 30 patients receiving earrings with a surface layer consisting of 24-carat gold and 30 patients earrings with a surface layer of titanium nitride, virtually indistinguishable from gold. The patients wore the earrings for 8 weeks. During the study, any dermatitis on the earlobes, as well as on other body sites, was registered. The skin reactions observed were weak but, in total, 17 of the 60 patients had a skin reaction (local or remote) during the study, 12 of whom had received gold earrings and 5 titanium (p<0.05). 11 patients had a reaction on the earlobes, 7 of whom had received gold earrings and 4 titanium (NS). With these facts it is hard to exclude that exposure to gold jewelry can be clinically relevant in persons hypersensitive to gold.

Adult↗
PubMed2000

Identification of Lilial as a fragrance sensitizer in a perfume by bioassay-guided chemical fractionation and structure-activity relationships.

Fragrance materials are among the most common causes of allergic contact dermatitis. The aim of this study was to identify in a perfume fragrance allergens not included in the fragrance mix, by use of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships (SARs). The basis for the investigation was a 45-year-old woman allergic to her own perfume. She had a negative patch test to the fragrance mix and agreed to participate in the study. Chemical fractionation of the perfume concentrate was used for repeated patch testing and/or repeated open application test on the pre-sensitized patient. The chemical composition of the fractions giving a positive patch-test response and repeated open application test reactions was obtained by gas chromatography-mass spectrometry. From the compounds identified, those that contained a "structural alert" in their chemical structure, indicating an ability to modify skin proteins and thus behave as a skin sensitizer, were tested on the patient. The patient reacted positively to the synthetic fragrance p-t-butyl-alpha-methylhydrocinnamic aldehyde (Lilial), a widely used fragrance compound not present in the fragrance mix. The combination of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships seems to be a valuable tool for the investigation of contact allergy to fragrance materials.

Aldehydes↗
PubMed1999

Occupational allergic contact dermatitis from olive oil in a masseur.

Contact allergy to olive oil is considered rare. There are 20 cases of contact allergy to olive oil described, and 3 of these had an occupational hand eczema as a result of olive oil. We describe a masseur who was allergic to olive oil, resulting in an occupational hand eczema. Both patch tests and a use test with olive oil was undertaken. An oral provocation with olive oil was also performed. Both patch tests were positive, as was the use test after 2 days. The oral provocation test was negative. Despite contact allergy to olive oil being rare, sensitization occurs. The external use of olive oil should be discouraged, at least in masseurs, when used under occlusion, and in long-standing dermatoses.

Dermatitis, Allergic Contact↗
PubMed1999

Individual variation in nickel patch test reactivity.

BACKGROUND AND OBJECTIVE: Various factors such as hormones, drugs, and ultraviolet (UV) radiation may influence patch test reactions. The aim was to study the individual variation in nickel reactivity, also in relation to the menstrual cycle. METHODS: Thirty women allergic to nickel were studied for 7 months with patch tests with a serial dilution of nickel sulfate in water on four different test occasions. The patients belonged to two different eczema groups, one with nickel allergy, atopy, and pompholyx (12 patients); and the other with nickel allergy, but without both atopy and hand eczema. RESULTS: None of the patients showed the same patch test reactivity on all four occasions, and the highest individual difference noticed was 250 times for the four test occasions. Furthermore, two of the patients had completely negative test reactions on at least one test occasion. CONCLUSION: The variation in nickel reactivity as shown in this article is of great importance and should be kept in mind when a patient has a positive history of allergic contact dermatitis but negative patch test results to nickel.

Adult↗
PubMed1999

Demonstration of the contact sensitizer p-tert-butylcatechol in p-tert-butylphenol formaldehyde resin.

BACKGROUND: In regard to patients hypersensitive to p-tert-butylphenol formaldehyde resin (PTBP-F-R), it is for diagnostic, therapeutic, and preventive reasons necessary to know the identity of the primary sensitizing substances and their sensitizing capacities, as well as their cross-reaction patterns. In patients hypersensitive to PTBP-F-R, we have demonstrated a statistically significant overrepresentation of simultaneous reactions to p-tert-butylcatechol (PTBC). In the guinea pig, we have shown that PTBC is a strong sensitizer, giving cross reactions to p-tert-butylphenol. Furthermore, PTBC cross reacts to the PTBP-F-R monomer 2,6-methylol p-tert-butylphenol, which is a strong sensitizer in the guinea pig. OBJECTIVE: The aim of this study was to investigate the background to the observed simultaneous reactions to PTBP-F-R and PTBC and to see if these could be explained by the presence of PTBC in PTBP-F-R. METHODS: High pressure liquid chromatography (HPLC), nuclear magnetic resonance spectrometry (NMR), mass spectrometry (MS). RESULTS: PTBC was isolated and identified; the concentrations in two resins were determined. HPLC analyses showed the presence of 0.099% and 0.020% wt/wt PTBC, respectively. CONCLUSION: This study shows that PTBC can be present in at least in some brands of PTBP-F-R. The study also indicates that a positive patch test reaction to PTBP-F-R could be an indication of allergy to PTBC, at least in patients with high sensitivity to PTBC. When detecting contact allergies to PTBP-F-R in a patient for whom no clinically relevant exposure to this resin can be found, the possibility of PTBC as the eliciting factor should be considered.

Antioxidants↗
PubMed1999

The benefit of patch testing with a corticosteroid at a low concentration.

BACKGROUND: Patch testing with corticosteroid marker molecules is advocated because testing with all available corticosteroids is impossible in clinical practice. Most commonly used are budesonide, tixocortol pivalate, and hydrocortisone-17-butyrate. We have been patch testing not only with the three markers, but also with two corticosteroid mixes, each consisting of different concentrations of the three markers. OBJECTIVE: We describe a patient allergic to tixocortol pivalate, who was diagnosed by using a lower patch test concentration that recommended, 0.1% in petrolatum, as well as a weak corticosteroid mix, 0.202%. METHODS: The patient was patch tested to a standard series, including the two corticosteroid mixes and its three constituents. RESULTS: None of the corticosteroid preparations were positive on the first ordinary reading day, day 3, whereas both tixocortol pivalate at 0.1% and the corticosteriod mix at 0.202% were positive on the second ordinary reading day, day 7, whereas all tested corticosteroids in the standard series gave positive reactions on d10. CONCLUSION: The possible benefit of patch testing with a corticosteroid at a low concentration is supported, as is the significance of late readings beyond D4.

Administration, Topical↗
PubMed1999

Lyral is an important sensitizer in patients sensitive to fragrances.

Contact allergy to fragrances is a common problem world-wide. The currently used fragrance mix (FM) for patch testing has only eight constituents and does not identify all fragrance-allergic patients. As perfumes may contain 100 or more substances, the search for markers for allergy continues. The synthetic fragrance 4-(4-hydroxy-4-methylpentyl)-3-cyclohexene carboxaldehyde (Lyral) was tested together with the FM and 11 other fragrance substances on consecutive patients in six European departments of dermatology. All patients were carefully questioned regarding a history of reactions to scented products in the past and were grouped into four categories: 'certain', 'probable', 'questionable' and 'none'. Lyral (5% in petrolatum) gave a positive reaction in 2.7% of 1855 patients (range 1.2-17%) and ranked next to 11.3% with FM allergy. Twenty-four patients reacted to both Lyral and FM, but 21 (1.1%) reacted positively only to Lyral. Of 124 patients with a 'certain' history, 53.2% reacted to the FM and a further 7.2% to Lyral only. If any kind of history of fragrance intolerance was given, 80% (40 of 50) of Lyral positive patients had a 'positive' history while only 58.6% (123 of 210) of FM positive patients had such a history; this difference was significant at P < 0.01. Lyral was identified by gas chromatography-mass spectrometry in some products which had caused an allergic contact dermatitis in four typical patients who showed a patch test positive to Lyral and negative or doubtful to FM. In conclusion, we recommend the testing of 5% Lyral (in petrolatum) in patients suspected of contact dermatitis.

Adult↗
PubMed1999

Simultaneous p-tert-butylphenol-formaldehyde resin and p-tert-butylcatechol contact allergies in man and sensitizing capacities of p-tert-butylphenol and p-tert-butylcatechol in guinea pigs.

In patients who are hypersensitive to p-tert-butylphenol-formaldehyde resin (PTBP-F-R), it is necessary, for diagnostic, therapeutic, and preventive reasons, to know the identity of the primary sensitizing substances, their sensitizing capacities, and their crossreaction patterns. The aims of this study were to investigate the presence of a simultaneous p-tert-butylcatechol (PTBC) contact allergy in individuals who were hypersensitive to PTBP-F-R, to investigate the sensitizing capacity of PTBC and p-tert-butylphenol (PTBP) in guinea pigs, and to study any crossreaction patterns. In 294 dermatitis patients tested with PTBP-F-R and PTBC, there was a statistically significant over-representation of simultaneous test reactions. Use of the guinea pig maximization test demonstrated that PTBC is a strong sensitizer giving crossreactions to PTBP. PTBP, however, failed to induce sensitization.

Administration, Topical↗
PubMed1999

Occupational dermatoses in composite production.

In a plant that produces fiber-resin composite by impregnation of cellulose fibers with phenol-formaldehyde and melamine-formaldehyde resins, a new technique was introduced that resulted in problems in the handling of uncured products. Many workers suffered dermatitis on areas of exposed skin. A primary investigation found that some workers had an occupationally related skin disease with contact allergy to work materials. We undertook a survey of occupational dermatoses, based on a questionnaire, clinical examination, and patch test with a standard series and a series of products and chemicals representing the work environment. Eighty-eight workers participated in the clinical investigation. In six workers, contact allergy to phenol-formaldehyde resin was seen, and in five workers, contact allergy to melamine-formaldehyde resin was noted. Two workers were allergic to both resins. Occupational dermatitis was diagnosed in nine of 88 (10.2%) workers. In this article, we discuss possible preventive measures for avoiding occupational dermatitis.

Adult↗
PubMed1999

Patch testing with budesonide in serial dilutions: the significance of dose, occlusion time and reading time.

Budesonide is advocated as a marker molecule for corticosteroid contact allergy. When patch testing corticosteroids, one must consider their sensitizing potential but also their anti-inflammatory properties, as well as the possibility of different time courses for such properties. The dose-response relationship for budesonide was therefore investigated with regard to dose, occlusion time, and reading time. 10 patients were patch tested with budesonide in ethanol in serial dilutions from 2.0% down to 0.0002% with occlusion times of 48, 24, and 5 h. Readings were on D2, D4, and D7. The 48-h occlusion picked up most positive reactors, 8/10. The D4 reading (48-h occlusion) detected most positive reactors, 8/10, and here 0.002% picked up most contact allergies. Late readings favoured high concentrations. The "edge effect" was noted for several concentrations at early readings. Due to the individual corticosteroid reactivity, the dose-response relationship and the time courses of the elicitation and the anti-inflammatory capacity, several features may be explained, i.e., that lower concentrations may detect budesonide allergy better at early readings, that patients with an "edge reaction" can have positive reactions to lower concentrations.

Administration, Topical↗