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W Uter

Publications and source records attributed to W Uter.

At least 37 records · Page 2Linked to original sources
PubMed2005

[Residual particle free rough surfaces after rough blasting with steel grit in total hip arthroplasty].

INTRODUCTION: Several shot peening and grit blasting techniques are used to modify the surface in the production of hip endoprostheses. A number of publications in maxillo- facial- surgery and orthopedic surgery demonstrated significant contamination on alumina blasted surfaces. Latest research studies suspected an association between surface contamination and early failure of endoprostheses associated with third body wear. Additionally, the European standard EN 12010 requires surfaces free of residual particles. The aim of this study is to evaluate the effects of rough blasting using steel grit followed by a pH dependent cleaning procedures with regard to complying with EN 12010. MATERIAL AND METHOD: Ti6Al7Nb rods were rough blasted 1 time using steel grit ("Stahldrahtkorn", hardness: 56 HRC; R+K Draht GmbH, Leisnig). All blasting procedures were carried out with a special grit blasting device with direct pressure. One Ti6Al7Nb rod each was grit blasted with 3 and 4 bar pressure and 10 rods with 5 bar pressure. Surface roughness was measured by means of Mitutoyo- Surftest 301 three times before and after grit blasting. The mean value was calculated. A field emission scanning electron microscopy (SEM, LEO 1525) was used for the detection of residual particles on the surface of the rods with a backscattered electron detector. RESULTS: By rough blasting using steel grit a mean roughness of 54,9 microm and a maximum roughness of 61,4 microm could be achieved. The surface of all rods showed a considerable contamination with steel particles after grit blasting. After the a pH- dependent cleaning procedure a residual particle free surface was detected in all samples. DISCUSSION: The European standard EN 12010 can be fulfilled using rough blasting with steel grit followed by a pH dependent cleaning procedure.

Alloys↗
PubMed2004

Monitoring of nevus density in children as a method to detect shifts in melanoma risk in the population.

BACKGROUND: Nevus density in children, a well-known risk factor for malignant melanoma, depends both on constitutional factors and on previous ultraviolet (UV) exposure. Secular trends of childhood UV exposure could thus be indirectly monitored by repeated standardized surveys assessing nevus density in children, such as the "childhood monitoring of nevus density (CMONDE-Study)". METHODS: Two complete surveys comprising all children at the time of school enrolment were performed in the city and county of Göttingen, Germany, during the years 1999 and 2000. A total of 4252 children with a median age of 6.25 years were examined as part of the mandatory school enrolment health assessment, and complete data were available for 3881 children. RESULTS: Median nevus density was 5.8/m(2) in the entire study group. The subgroup-specific median increased from "Fitzpatrick skin type" IV to II, but the density was not increased for the type I subgroup. Similarly, nevus density rose with increasing lightness of hair color, but was very low in red-haired individuals. While the number of freckles was also strongly associated with nevus density, the association between iris color and skin reflectance, respectively, was weak. The duration of the additional examination for CMONDE was on average 3-5 min per child. CONCLUSION: We regard CMONDE as a highly feasible surveillance instrument, which should be implemented as an important addition to regular regional or national health reporting.

Child↗
PubMed2004

Allergic and non-allergic periorbital dermatitis: patch test results of the Information Network of the Departments of Dermatology during a 5-year period.

Periorbital dermatitis is common and can be due to the external use of ophthalmic drugs. We evaluated patch test results of the Information Network of the Departments of Dermatology. During a 5-year period (1995-99), of a total 49,256 patch-tested patients, 1053 (2.1%) were eventually diagnosed as allergic periorbital contact dermatitis (APD) and 588 (1.2%) as non-allergic periorbital dermatitis (NAPD). Patient characteristics between APD, NAPD and other cases (OCs) differed with respect to sex (19.7% male in both periorbital groups versus 36.3% in OCs), atopic dermatitis (10.4% in APD versus 60.2% in NAPD versus 16.9% in OCs) and age, APD being substantially more often (68.2%) aged 40 and above than NAPD (52.6%). Several of the top allergens in OCs [such as fragrance mix, Myroxylon pereirae resin (balsam of Peru), lanolin alcohol and potassium dichromate] caused significantly fewer positive test reactions in both periorbital groups. In contrast, thimerosal, phenylmercuric acetate, sodium disulfite, gentamicin sulfate, phenylephrine hydrochloride and benzalkonium chloride tested positively significantly more often in APD but not in NAPD, verifying them as true ophthalmic allergens. Finally, in 42 cases (4%) of APD patients, additional allergens were identified by testing of the patients' own substances (mostly beta-blockers, oxybuprocaine and dexpanthenol), supporting the necessity of testing with ophthalmic drugs as is where individual substances are not readily available.

Adult↗
PubMed2004

Iodopropynylbutyl carbamate 0.2% is suggested for patch testing of patients with eczema possibly related to preservatives.

BACKGROUND: Iodopropynyl butylcarbamate (IPBC) is a new preservative in medical and cosmetic leave-on products. Although cases of allergic contact dermatitis to IPBC have been reported, it is not known whether the usual test concentration of 0.1% is appropriate for screening tests with IPBC. OBJECTIVES: To determine the concentration of IPBC that should be used in screening patch tests. METHODS: An analysis was made of data filed by 26 centres of dermatology on patch tests performed with one or two concentrations of IPBC (0.1%, 0.2%, 0.3% or 0.5%) in 8106 unselected patients. Criteria used to determine the best test concentration of IPBC were the reaction index, the positivity ratio, the rate of crescendo reactions, and the relations between IPBC reactions and the MOAHLFA index irritant reactions to sodium lauryl sulphate (SLS), and allergic reactions to other contact allergens including preservatives. RESULTS: IPBC 0.1%, 0.2%, 0.3% and 0.5% yielded 0.5%, 0.8%, 1.3% and 1.7% positive reactions, but this increase was accompanied by an even greater increase in doubtful and irritant reactions. These figures and the other criteria examined suggested the range of suitable test concentrations of IPBC to lie between 0.2% and 0.3%. A detailed analysis of MOAHLFA indices and of associations between reactions to IPBC and reactions to other allergens and to SLS showed that most of the positive reactions to IPBC 0.2% can be assumed to be allergic ones and that with IPBC 0.2% fewer false-positive reactions can be expected than with IPBC 0.3%. CONCLUSIONS: Patch testing with IPBC 0.2% is suggested for patients with eczema possibly related to preservatives.

Adult↗
PubMed2004

Inter-relation between variables determining constitutional UV sensitivity in Caucasian children.

BACKGROUND/PURPOSE: Sensitivity to ultraviolet (UV) light is associated with phenotypic variables like iris or hair colour or freckling, which are all strongly inter-related. We assessed the pattern of association among these factors to construct a summary measure reflecting constitutional UV sensitivity in a simple one-dimensional score with sufficient discriminating power. METHODS: Information on iris and hair colour (3 and 4 categories, respectively), freckling (none vs. any) and the reaction to mid-day summer sunlight as an outcome (dichotomized into 'burn' and 'tan') was collected in a cross-sectional study among children at school enrollment in 1999 and 2000 in Göttingen, Germany (n=3765 with complete data). Chi-squared automatic interaction detector (CHAID) analysis and log-linear modelling was used to assess the pattern of mutual inter-relations. RESULTS: Hair colour turned out to be the factor most strongly associated with UV sensitivity. In case of blonde or brown hair (the most common phenotypes in our sample), the consideration of freckling further refined the classification system, whereas iris colour did not contribute additional information. The results of the CHAID and log-linear analyses suggest a simple five-point score capturing constitutional UV sensitivity. The discriminating power of this score was high in our sample, with the proportion of persons who burned ranging from 7.7 (lowest category) to 73% (highest category). CONCLUSION: The new scoring system summarized efficiently relevant information on individual constitutional UV sensitivity in our sample. Its further validation in independent studies comprising Caucasian children or adults is necessary to assess objectively its properties for future applications.

Child↗
PubMed2003

[Epidemiologic surveillance of contact allergens. The "monitoring series" of IVDK (Information Network ofDermatologic Clinics for Detection and Scientific Evaluation of Contact Allergy].

The selection of the most important contact allergens is subject to a continuous change. Several factors may influence the sensitization rates and thus the decision, which substances to include in the standard series of the most frequent allergens. The Information Network of Departments of Dermatology adds substances of interest for a certain time period to the standard series in order to evaluate parameters such as sensitization rate, grade of reaction, and clinical relevance of positive reactions. In 6 testing periods starting in 1996, 13 test substances were evaluated. Due to the results, propolis, compositae mix, and bufexamac were included in the standard series in 1999, while lyral was added in 2002. Sorbitansesquioleat, dispers blue mix, and iodopropynyl butylcarbamate are under further discussion. Substances such as glutaraldehyde and p-aminoazobenzole should be tested in certain risk groups only, whereas the steroids budesonide and tixocortol should be tested when clinically suspected.

Allergens↗
PubMed2003

[Decrease in nickel sensitization in young patients--successful intervention through nickel exposure regulation? Results of IVDK, 1992-2001].

BACKGROUND: In the early 1990s, the prevalence of nickel contact allergy was high-almost 20% on a population level, and some 40% in contact dermatitis patients. Around that time, nickel exposure was starting to be regulated. PATIENTS/METHODS: Descriptive and bivariate analyses of patch test results of all patients tested with nickel sulfate (5% pet.) in the departments joining the Network of Departments of Dermatology (IVDK) 1992-2001 (n=82,991, women: 52,709; men: 30,282). The annual frequency of sensitization to nickel was analyzed in women and men in four age subgroups (<31/31 to <44/44 to 58= or >58). RESULTS: In young women less than 31 (n=13.909) the prevalence of contact allergy to nickel decreased significantly from 36.7% in 1992 to 25.8% in 2001. In young men in the same age group (n=7087), the prevalence dropped from 8.9% in 1992 to 5.2% in 2001. CONCLUSIONS: The observed decline indicates that measures to limit the release of nickel from costume jewelry helped reduce the prevalence of nickel allergy. In general term, allergen elimination or reduction is an effective primary prevention strategy which does not depend on individual behavior modifications.

Adolescent↗
PubMed2003

[Severe allergic contact dermatitis with generalized spread due to bufexamac presenting as the "baboon" syndrome].

HISTORY AND CLINICAL FINDINGS: A 48-year-old woman presented with acute, pruritic, sharply demarcated, erythematous, maculopapulous exanthem in the anogenital area with disseminated maculae over the back. Several days before, the patient had applied as topical treatment a bufexamac-containing ointment to the anal region. INVESTIGATIONS: The patch test showed an allergic test reaction to bufexamac. DIAGNOSIS: The case presents a serious allergic contact dermatitis with generalization, imitating a baboon syndrome, unequivocally linked to the previous topical treatment. CONCLUSION: During the last 10 years allergic reactions to bufexamac have increasingly been reported, sometimes with erythema multiforme-like reactions. Because of the high rate of sensitization, the serious clinical course of bufexamac allergy and the insidious symptoms of this side effect, sometimes mimicking the disease to be treated, the substance should be used neither for proctological nor for dermatological diseases, even more as these patients are considered to be at high risk of developing allergic contact dermatitis because of the abnormal skin barrier. Considering the data presented, the use of bufexamac should be critically reassessed.

Administration, Topical↗
PubMed2003

Association between infections and signs and symptoms of 'atopic' hypersensitivity--results of a cross-sectional survey among first-year university students in Germany and Spain.

BACKGROUND: This study assessed the hypothesis that a decreased exposure to childhood infectious diseases is associated with signs and symptoms of 'atopic' hypersensitivity diseases. METHODS: A cross-sectional survey was performed among 1368 Spanish and German first-year university students between 1997 and 1999, including self-administered questionnaire data and serological tests. RESULTS: No association between the disease outcomes and hepatitis A, Helicobacter pylori infection and herpes simplex infection was observed in logistic regression analyses, adjusting for potential confounders (centre, sex, smoking, parental education). In contrast, vaccination against hepatitis B was associated with a decreased risk for the outcomes allergic rhinitis (OR 0.63, 95% CI: 0.42-0.95) and total serum IgE above 100 U/ml (OR 0.56, 95% CI: 0.39-0.81). Conversely, seropositivity to HBc antigen was significantly associated with high total serum IgE (OR 2.04, 95% CI: 1.34-3.06). CONCLUSIONS: Our study partly confirmed and partly contradicted previous evidence and hypotheses, respectively, concerning the role of the infections considered. The observation of a decreased risk in persons vaccinated against hepatitis B warrants further, prospective investigation.

Adolescent↗
PubMed2003

Patch testing with the irritant sodium lauryl sulfate (SLS) is useful in interpreting weak reactions to contact allergens as allergic or irritant.

Several contact allergens are tested at concentrations which might cause irritant reactions. In this study we investigated whether the reactivity to a standard irritant is useful in identifying subjects with hyperreactive skin yielding a higher rate of doubtful or irritant reactions. Sodium lauryl sulfate (SLS) 0.5% (aqua) was tested in addition to the standard series routinely for 5 years in the Department of Dermatology, Dortmund. For data analysis, we compared reactions at D3 to the standard series, the vehicle/emulsifier and preservative series and benzoyl peroxide to the reactions obtained with SLS. Proportions were standardized for age and sex. The association between reactivity to a certain allergen and SLS reactivity as a dichotomous outcome, controlled for age and sex as potential confounders, was assessed with logistic regression analysis. Results showed that of the 1600 tested patients, 668 (41.8%) had an irritant reaction to SLS which exceeded 2 + in only 41 patients. Seasonal variation was statistically significant, showing reduced SLS reactivity in summer vs. winter. Patients with irritant reactions to SLS showed significantly more erythematous reactions to the following 10 allergens of the standard series: fragrance mix, cobalt chloride, balsam of Peru (Myroxylon pereirae), lanolin alcohol, 4-phenylenediamine base (PPD), propolis, formaldehyde, N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), benzocaine, and 4-tert-butylphenol-formaldehyde resin. No significant differences regarding strong positive allergic reactions were observed. Concerning other allergens, significantly more erythematous reactions were observed in SLS-reactive patients to benzoyl peroxide, octyl gallate, cocamidopropyl betaine, Amerchol L-101, tert-butylhydroquinone, and triethanolamine. In the SLS-reactive group of patients, the reaction index was negative for 10 allergens of the standard series compared to only 5 in the SLS non-responder group. For the first time, this study, based on a large data pool, revealed a significant association between reactivity to the irritant SLS and erythematous reactions to certain allergens. With SLS as a marker for hyperreactive skin at hand, some of these reactions can now be classified as irritant more confidently, particularly if there is no history of exposure to the allergen.

Allergens↗
PubMed2003

Risk factors for contact allergy to nickel - results of a multifactorial analysis.

To quantify the independent impact of potential risk factors for nickel contact allergy (NCA), a multifactorial Poisson regression analysis of standardized anamnestic and patch test data (with nickel sulfate, 5% in petrolatum) was performed, comprising 74 940 patients assessed in the 33 German and Austrian contact dermatitis units of the Information Network of Departments of Dermatology (IVDK) between 1992 and 2000. NCA was observed in 15.5% patients. Female sex was the strongest risk factor (prevalence ratio 3.74, 95% CI: 3.51-3.98). Risk increased monotonically and significantly with decreasing age. Atopic dermatitis was not a risk factor. The year of patch test had no influence on NCA risk. Significant variation of risk between occupations was observed. In conclusion, our multifactorial analysis was able to quantify the impact of established risk factors and additionally address other, e.g. occupational, factors yet unidentified.

Adult↗
PubMed2003

Frequency of sensitization to antimicrobials in patients with atopic eczema compared with nonatopic individuals: analysis of multicentre surveillance data, 1995-1999.

BACKGROUND: Atopic eczema, a multifactorial disease, is influenced by bacterial factors, particularly Staphylococcus aureus. Consequently, treatment includes therapy with antibiotics and nonantibiotic antimicrobials. OBJECTIVES: In our study the sensitizing potential of some topical antimicrobials was investigated by comparing proportions sensitized to various antibiotics and antiseptics between patients with current or past atopic eczema, and patients who had never had atopic eczema. METHODS: Data of all patients patch tested in the Departments of Dermatology participating in the Information Network of Departments of Dermatology (IVDK) between 1995 and 1999 were analysed. Patients with a current leg ulcer or stasis dermatitis that might cause a confounding effect were excluded. RESULTS: Controlling for the additional confounding effect of sex and particularly age, we did not find that patients with atopic eczema had a generally higher risk compared with nonatopic individuals. CONCLUSIONS: While the risk of sensitization should always be considered when applying topical therapy, our data-within the methodological limitations of this type of study-would not support a very restrictive use of these agents in the management of atopic eczema.

Adult↗
PubMed2003

[Sensitization to tea tree oil in Germany and Austria. A multicenter study of the German Contact Dermatitis Group].

BACKGROUND AND AIM: Tea tree oil, a distillation product of the Australian tea tree (Melalence alternitolia) is increasingly used as an alternative remedy for various dermatological diseases. Tea tree oil contains several allergenic monoterpenes and sesquiterpenes. In this multicenter study it was evaluated, whether the increasing use of tea tree oil has lead to an increased frequency of sensitization in Germany and Austria which would justify its inclusion into the standard series. PATIENTS AND METHOD: For patch testing a standardized tea tree oil was used, dissolved 5% in diethylphtalate (DEP). Consecutive patients of 11 dermatological departments in Germany and Austria were tested. Readings were taken on day 2 and 3 according to the guidelines of the German Contact Dermatitis Research Group (DKG). RESULTS: 5% tea tree oil was positive in 36/3375 patients (1.1%). Sensitization frequencies showed great regional variations and ranged from 2.3% (Dortmund), 1.7% (Buxtehude), 1.1% (Essen), 0.7% (Graz), to 0% (Berlin, Vienna). 14/36 patients (38.9%) also showed a positive patch test reaction to oil of turpentine. CONCLUSION: Our results show that tea tree oil is an important contact allergen for some centers. It should be tested, if medical history suggests its previous use. Considering the great regional differences in frequencies of sensitization its inclusion into the standard series is not recommended yet.

Adult↗
PubMed2002

The spectrum of allergic (cross-)sensitivity in clinical patch testing with 'para amino' compounds.

BACKGROUND: Allergic contact sensitization to 'para amino' compounds is frequent and the spectrum of cross-reactivity between members of this chemical group is variable. METHODS: A retrospective analysis of clinical patch test data obtained with a special test series in the centres of the Information Network of Departments of Dermatology (IVDK) between 1995 and 1999. RESULTS: In the 638 patients tested with the above test panel positive reactions were observed most often to p-aminoazobenzene (16.2%), p-phenylenediamine (14.1%), p-toluylenediamine (10.0%), followed by 4,4'-diaminodiphenylmethane (8.5%), Disperse Orange 3 (8.4%) and p-aminophenol (3.1%). Among the 544 patients tested with p-phenylenediamine and all seven additional 'para amino' compounds, concordance between reactions varied greatly. The stronger the positive test reaction to p-phenylenediamine, p-toluylenediamine or p-aminoazobenzene, the more frequently additional positive reactions to the other compounds were observed. CONCLUSIONS: A screening employing several 'para amino' compounds is necessary to describe the individual spectrum of allergic contact sensitization, as there is no reliable marker substance. Further research should aim at (i) establishing the mechanism of cross-reactivity to 'para amino' compounds and (ii) identifying exposures in the environment.

4-Aminobenzoic Acid↗
PubMed2002

The preservative iodopropynyl butylcarbamate: frequency of allergic reactions and diagnostic considerations.

The preservative iodopropynyl butylcarbamate (IPBC) (0.1% in petrolatum) was tested in 4883 consecutive patients for 18 months between January 1998 and June 1999. With regard to the MOAHLFA-Index, the study population comprised 37% males; 17% with occupational and 19% with atopic dermatitis; 31% with hand, 10% with leg and 17% with face dermatitis; 61% were age 40 and above. According to readings at D3, 0.3% were allergic to IPBC, with 14 + and 2 + + reactions. Doubtful or irritant reactions occurred twice as frequently. Patients exposed for 24 h (n = 1814) reacted less frequently (0.1%) than the remaining patients exposed for 48 h (0.5%). Considering the possibility that a certain proportion of + reactions could be false positive, the reaction pattern was evaluated. More than 80% of the positive reactions displayed a crescendo or plateau time pattern. Furthermore, 18 of 43 doubtful reactions (?) appeared as late as D3 (thus, these could be false negative), whereas the majority of doubtful reactions occurred earlier and displayed a decrescendo pattern (corresponding to a typical irritant pattern). In conclusion, the large proportion of '?' reactions may be due not only to the irritant potential of the substance, but also to test concentrations not being high enough to elicit an allergic reaction. We propose that higher concentrations of IPBC (0.3%) should be evaluated in a study also addressing suitable validation tests like ROAT or PUT.

Adult↗