Cross reaction pattern of 26 acrylic monomers on guinea pig skin *

The cross reaction pattern of acrylic monomers was investigated in 20 groups of animals sensitized to a different acrylic monomer. Aminals sensitized to one monoacrylated tend to react to other monoacrylates. Reactions to a corresponding monomethacrylates (same alcohol group in the ester) or other monomethacrylates did not occur. Some reactions to di(meth)acrylates were observed. A number of animals sensitized to one monomethacrylated to some other monomethacrylates and to monoacrylates. Reactions to di(meth)acrylates were observed. Animals sensitized to di(meth)acrylates showed hardly any positive cross reaction. A universal screening allergen to detected acrylic monomer sensitizations does not exist. The composition of (industrial) products should be made accessible to the occupational dermatologist in order to prevent the undresirable situation in which a patient suspected of having an acrylic monomer sensitization must be tested with a large series of potent allergens in order to detect the real origin of the sensitization.     

Factors affecting the attachment of Treponema pallidum to mammalian cells in vitro.

Attachment of Treponema pallidum (Nichols) to mammalian cells is probably the first step in the pathogenesis of syphilis. It may also be important for the multiplication of T pallidum in vitro. When factors affecting the attachment of T pallidum to mammalian cells in vitro were studied significantly greater numbers of treponemes were found to attach to baby rabbit genital organ (BRGO) cells than to five other mammalian cell lines. When attached to BRGO cells T pallidum survived longer in vitro than unattached treponemes. Eagle's minimal essential medium was superior to three other culture media in increasing attachment and maintaining the survival of treponemes. Dithiothreitol (0.25-1.0 mmol/l) had no effect on the attachment of T pallidum to BRGO cells. Anaerobic conditions were superior to microaerophilic conditions, and the latter were superior to aerobic conditions for the attachment and survival of T pallidum to BRGO cells. Within the range of concentrations tested the number of treponemes attached to the BRGO cells was directly dependent on the concentrations of viable treponemes in the inoculum. Greater numbers of treponemes attached to actively metabolising BRGO cells than to quiescent or slowly growing cells.     

Factors affecting the attachment of Treponema pallidum to mammalian cells in vitro

Attachment of Treponema pallidum (Nichols) to mammalian cells is probably the first step in the pathogenesis of syphilis. It may also be important for the multiplication of T pallidum in vitro. When factors affecting the attachment of T pallidum to mammalian cells in vitro were studied significantly greater numbers of treponemes were found to attach to baby rabbit genital organ (BRGO) cells than to five other mammalian cell lines. When attached to BRGO cells T pallidum survived longer in vitro than unattached treponemes. Eagle's minimal essential medium was superior to three other culture media in increasing attachment and maintaining the survival of treponemes. Dithiothreitol (0.25-1.0 mmol/l) had no effect on the attachment of T pallidum to BRGO cells. Anaerobic conditions were superior to microaerophilic conditions, and the latter were superior to aerobic conditions for the attachment and survival of T pallidum to BRGO cells. Within the range of concentrations tested the number of treponemes attached to the BRGO cells was directly dependent on the concentrations of viable treponemes in the inoculum. Greater numbers of treponemes attached to actively metabolising BRGO cells than to quiescent or slowly growing cells.     

Hypersensitivity to thimerosal: the sensitizing moiety

There has been increasing interest in characterizing the sensitizing moiety of thimerosal [TIM]. following the finding that patients with photosensitivity to piroxicam arc allergic to the thiosalicylic acid [TIO] moiety of TIM. For this purpose, the authors have conducted 2 studies in TIM-sensitive patients. In the 1st. of 175 patients tested with TIO and ammoniated mercuric chloride [HGAM|, 45.7% reacted only to TIM, whereas 45. 7%. reacted also to TIO and 17.7%. also to HGAM: 9.1% reacted to both TIO and HGAM. In the 2nd. of 47 patients tested with TIO and ethylmercuric chloride [F.THG], 87.2% reacted to ETHG. 44.7% to TIO and 31.9% reacted to both. None of the patients reacted only to TIM. The authors conclude that thimerosal allergy is due either to the mercuric moiety or to thiosalicylic acid, with no cases of sensitivity only to the whole molecule of TIM. TIM-sensitive patients are mainly allergic to the mercuric moiety. but among them there are a large number of TIO-sensitive patients, and these should be advised to avoid piroxicam.     

In pursuit of defining clinical relevance of positive patch tests results

According to the current classification of clinical relevance of the positive patch test reactions, the positive results of patients who are allergic to various allergens that are not responsible for the present dermatitis do not fit into the category of "relevant to present dermatitis" but should be defined as "relevant to a preceding bout of dermatitis." This seems to us inappropriate and misleading because reexposure to the sensitizing agent would quickly revert their reaction to "relevant to present dermatitis." We suggest an alternative possibility to the current division of the various types of clinical relevance, namely, "relevance to a present allergy other than the presenting dermatitis."     

Contact allergy and exposure patterns to thiurams and carbamates in consecutive patients

Sensitization to rubber is must often due to sensitization to thiurams. Positive patch test reactions to carbamates are less frequent, and usually only diagnosed in patients with positive patch test reactions to thiurams as well. The aim of the present study was to describe the relative frequency of sensitization to thiuram mix (TH mix) and zinc diethyldithiocarbamate (ZDC) in a population where the exposure to these chemicals from rubber gloves was previously studied and considered to be of approximately the same order of magnitude. The thiuram derivatives seemed to be the most important sensitizers (frequency 2.8%) compared to ZDC (frequency 0.5%) which has been the most frequently reported sensitizer among the carbamates in rubber gloves. An interesting observation was that the probability that the patient was reacting to ZDC was strongly associated with the strength of the patch test reaction to TH mix. This observation may add a new aspect to the discussion about cross-reactivity versus concomitant sensitization of thiurams and carbamates.     

Disease and disease control. International Leprosy Congress, Beijing, 7-12 September 1998. Workshop report.

Four workshops were conducted during the congress under the disease control theme. The workshops were on the issues of defining disease and antibacterial therapy, early case detection, sustaining leprosy control in low endemic situations, and the prevention of disability. These workshops spanned the spectrum of disease and its consequences through from early detection, the definition of disease to the prevention of disability. All of these topics being important contemporary issues challenging leprosy control programmes world wide. Despite the broad spectrum of the topics it was interesting to see that a number of important themes emerged which were common to all topics. It is possible to identify five major themes arising from the output of the workshops which are now described below. Each of the workshops adopted broad and comprehensive approaches to their topic. In the past, there has been narrowness in defining disease in terms of the need for chemotherapy. The approach taken in the workshop now is for a much more comprehensive approach looking at all the consequences of the disease process rather than the requirement for antibacterial chemotherapy. Similarly broad approaches were taken to low endemic situations, considering comprehensive approaches which are inclusive rather than exclusive. Disability prevention also continues this same theme of comprehensive approaches based on multidisciplinary involvement in prevention of the consequences of the disease process. The second major theme to be identified in the output of the workshops was the importance of relevance to patients and people affected by leprosy. It is no longer adequate to view programmes in terms of their acceptance to those running the programmes. Control programmes must be acceptable to the people they are designed to benefit. This even impacts on definitions of disease in terms of what matters to patients rather than only restricting this to disease pathology. Similarly, approaches to disability prevention are not merely about measurement of impairments due to nerve function deficit but rather consider the abilities and functions which are most important to the individuals affected. The third theme which spans all of the workshops is the need to develop partnerships with others in addressing the challenges of leprosy today. Each workshop identified important groups with which partnerships need to be developed included local patient groups, voluntary associations and primary health care services. All of these have a role to play, from early case detection right through to the prevention of disability and the sustaining of control under low endemic situations. The fourth important theme is sustainability of programmes which need to be developed for the long term benefit of those affected by disease rather than short term goals. Again, this impacts an area such as case detection methods which need to be sustained in the long term. Approaches such as intensive case detection through mass survey are not sustainable given changes to the patterns of disease, whereas involvement of communities and community participation in the process of early case detection is a much more sustainable approach. This is important, as programmes attain low endemic status and is also important in preventing disabilities where the progressive nature of secondary impairments following primary impairments may be lifelong. The final theme is that of the importance of training, as each area is recommending new approaches to be taken and for new people to be involved in leprosy programmes. The implications are that those to be involved need to be trained and that the training requirements will be different from those of the last ten years. Training programmes will need to adapt to a wider range of individuals and groups being involved in programmes and to much more comprehensive approaches. These implications for training are profound and training centres and training programmes rapidly     

Oral challenge with food additives

A randomized, placebo-controlled oral challenge with food additives (preservatives and food colorings) was carried out in 101 patients with eczema of undetermined origin who suspected that the intake of certain foods aggravated their dermatitis. 37 reacted to 1 or more of the food additives but not to a placebo, while 16 reacted to the placebo, or both the placebo and food additives. 48 had no reactions. The difference between the number of reactions to the food additives and the number of reactions to the placebo was not statistically significant. The reactions could be reproduced in only 1/3 of those challenged twice. It was not possible to correlate the reactions to food additives to reactivity to specific foodstuffs containing the same additives. If intolerance to food additives is suspected, an elimination diet seems warranted, regardless of whether the patient reacts to oral challenge with food additives.     

Delayed reactions to reusable protective gloves

The materials in plastic protective gloves are thought to cause less contact allergy than rubber gloves. Our aim was to estimate the frequency of delayed reactions to different types of reusable protective gloves among dermatitis patients. 2 × 2 cm pieces of polyvinyl chloride (PVC) gloves, nitrile gloves, and natural rubber latex (NRL) gloves were tested as is in consecutive dermatitis patients tested with the baseline series. Among 658 patients, 6 patients reacted to PVC gloves and 6 patients to the NRL gloves. None reacted to both these types of gloves. Five of six patients with reactions to rubber gloves reacted to thiuram mix in the baseline series. Delayed reactions to reusable PVC gloves may be as common as to reusable NRL gloves. In contrast to most reactions to the NRL glove, the reactions to the PVC glove had no obvious association with reactions to any allergen(s) in the baseline series.     

Effect of childhood and adolescent ultraviolet exposures on cumulative exposure in South East Queensland schools

Quantitative estimates of the childhood and adolescent erythemal ultraviolet (UV) exposure received in South East Queensland schools are provided in this paper for age groups 0 to 6, 7 to 12 and 13 to 19 years. For the neck, hand and lower arm, sites of high UV exposure that are generally not covered by clothing, 13 to 19 year olds received the highest exposure of the three age groups, followed by 7 to 12 year olds. Exposure for 13 to 19 year olds contributed up to 44% of cumulative exposure to 20 years of age, and exposures for the 7 to 12 year olds contributed up to 31%. If the annual UV exposure for these two age groups were reduced to the average of all the age groups, cumulative erythemal UV exposure from 0 to 20 years would be reduced by up to 16%. On the other hand, if mothers can protect their babies by reducing the level of annual exposure to 30% of the annual UV exposure of the 7 to 12 year olds for the first four years then cumulative exposure to UV to age 20 would be reduced by up to 19%. These data confirm the importance of targeting young age groups in public campaigns for sun protection.     

Immunological,chemical and clinical aspects of exposure to mixtures of contact allergens

Allergic contact dermatitis is one of the most frequent forms of skin inflammation. Very often, we are exposed to mixtures of allergens with varying potencies, doses/areas, and exposure times. Therefore, improved knowledge about immune responses to combinations of contact allergens is highly relevant. In this article, we provide a general introduction to immune responses to contact allergens, and discuss the literature concerning immune responses to mixtures of allergens. According to the existing evidence, increased responses are induced following sensitization with combinations of allergens as compared with single allergens. The response to a mixture of allergens can be both additive and synergistic, depending on the dose and combination of allergens. Importantly, sensitization with combinations of either fragrance allergens or metal salts can result in increased challenge responses to specific allergens within the mixture. Taken together, the immune responses to mixtures of allergens are complex, and further studies are required to obtain the necessary knowledge to improve consumer safety.     

Prevention-of-impairment-and-disabilities activities in leprosy after integration: role for physical medicine and rehabilitation personnel

Referral options for specialist care for prevention of impairment and disabilities are imperative in order to make an integrated leprosy control system work. This requires an understanding of the disease, in addition to the special skills for managing specific disabilities. Physical medicine and rehabilitation (PMR) personnel are better equipped to handle leprosy-related disabilities. They are well versed with biomechanical aspects of deformities, and are competent to provide splints, orthoses, etc. to the needy persons, and they can assess sensory motor functions and deformities. If PMR personnel can be trained in deformity correction they can become valuable resource persons for secondary and tertiary care of leprosy-affected persons. PMR persons, therefore, have the opportunity to volunteer themselves for this job to fill the void created by the fading out of leprosy surgeons. They will also have to bear additional responsibility to train general health care workers so as to empower them to look after the needs of those disabled by leprosy, many of whom will continue to be available for a number of years to come.     

National survey of doctors' actions following the diagnosis of a bacterial STD

OBJECTIVES: Little is known about the post-STD diagnosis management practices of community based doctors. The purpose of this study was to describe the reported actions that doctors take after diagnosing gonorrhoea, chlamydia, or syphilis and to determine if these actions differ across the three STDs. METHODS: A random national sample of 7300 doctors (70% response rate) practising in five medical specialties responded to 13 questions related to STD management. Mean differences across STDs were examined using the General Linear Model function of SPSS. RESULTS: Most doctors reported instructing patients to abstain from sex during treatment, to use condoms, and to inform their sexual partners of their exposure after diagnosing gonorrhoea, chlamydia, or syphilis. For syphilis, however, doctors were less likely to treat the patients presumptively and to give them drugs for their partners; and more likely to collect partner information, to follow up with the patient to see if the partner was referred for treatment and to send patient information to the health department. CONCLUSIONS: Doctors' post-STD diagnosis actions were similar for gonorrhoea and chlamydia compared to syphilis. Study findings suggest low levels of STD case reporting and partner follow up by doctors in the sample. Interventions are needed to educate community based doctors about the importance of partner follow up and case reporting in the management of STDs.     

Clinical allergy to cocamidopropyl betaine: reactivity to cocamidopropylamine and lack of reactivity to 3-dimethylaminopropylamine

7 patients allergic to cocamidopropyl betaine (CAPB) were detected by positive patch test reactions to Tegobetaine L7TM. These patients were then asked to participate in further testing to its potential impurities, cocamidopropylamine and 3-dimethylaminopropylamine (DMAPA). 4 of the 7 patients were tested to purified CAPB and cocamidopropylamine, with 2 reacting to the purified betaine on allergy patch testing and 3 reacting to cocamidopropylamine 0.1%. At another date, 6 of the 7 were successfully recalled for testing to DMAPA in the presence of sodium lauryl sulfate (SLS) or pure CAPB; 1/6 reacted to DMAPA in water, but only at very high concentrations, at least 3 orders of magnitude higher than that to which skin exposure would occur from use of products containing CAPB. Both SLS and CAPB increased the number of reactions recorded to high levels of DMAPA. However, positive reactions to much lower concentrations of DMAPA (>or=100 ppm) were found in only 1/6 subjects and then only in the presence of the irritant SLS. 0/6 reacted to pure CAPB alone. Taken together, these results suggest that DMAPA is unlikely to be an important contact allergen in CAPB of appropriate quality. They also confirm that CAPB of suitable purity, where levels of both cocamidopropylamine and DMAPA are minimized, is unlikely to trigger reactions in those ostensibly allergic to the material.     

The practical use of Z-plasty.

Properly employed, Z-plasty is a valuable way of avoiding complications of tension and contracture that may result in hypertrophic scars, and for repairing such scars if they occur. Careful preoperative planning to place the limbs of the Z in the lines of least tension and to make limbs of equal length at 60 degree angles to the central limb are essential to success. Cautious handling of the flaps and attention to hemostasis helps to ensure that success. Occasionally, Z-plasty has to be resorted to unplanned when it is found that an excision will result in tension exceeding expectations if primary closure were to be done.     

Standards und Fallstricke der In-vitro-Diagnostik der Insektengiftallergie

In patients with a history of anaphylactic sting reactions, in-vitro tests are performed in order to demonstrate venom sensitization to the causative venom. Measurement of specific IgE-antibodies (sIgE) to the natural composite venom represents the standard in-vitro method to demonstrate venom sensitization. If sensitization to the composite venom cannot be demonstrated, one may determine sIgE to recombinant allergen compounds, in order to demonstrate sensitization to molecular venom allergens. Moreover, several cellular tests are available to confirm venom sensitization. Herein basophils, which carry cell-bound sIgE, can be used to produce a confirmatory response upon incubation with venom allergens. Reactions to both honey bee and vespid venom may either indicate true double sensitization or cross sensitization. The identification of antibodies cross-reacting to venoms and to other allergen sources does not exclude clinical relevance. Elevated baseline serum tryptase is a risk factor for severe systemic reactions after a field sting and during venom immunotherapy (VIT), the latter in particular for VIT with vespid venom. Serum tryptase measurement should, therefore, be included into routine diagnostics of venom allergy. The measurement of IgG-antibodies specific to venom is not recommended for routine work-up. None of the mentioned in-vitro tests, which may be used before, during or after VIT, allow, however, a precise prognosis with respect to future sting reactions, or to side effects and to the efficacy of VIT, respectively. To validate the reason for a VIT, one should also consider patient history and results of other tests.     

Transient re-emergence of oil of turpentine allergy in the pottery industry

Allergy to oil Of turpentine has diminished largely due to the use of cheaper substitutes in many occupations. However, 2 particular areas still reliant on real oil of turpentine are those of the perfume industry and ceramic decoration. We report 24 cases of hand dermal it is in pottery workers involved in ceramic decoration, paintresses, liners, gilders, enamellers and a line china painter. seen in a 6-month period following a change from Portuguese to Indonesian turpentine, of whom 14 were sensitive to Indonesian turpentine. 8 to α-pinene. 4 to Δ-3-carene and 2 positive to turpentine peroxides, Previous reports suggest that, Δ-3-carene is the main allergen and reports of sensitivity to α-pinene in the absence of sensitivity to Turpentine peroxide, in particular to the hydro-peroxide of. Δ-3-carcne. are few. Turpentine allergy continues Lo be a problem in The pottery industry and is more common than allergy to the heavy metals of the colours used in ceramic decoration. α-pinene, an unusual allergen, appears to he the most common in our area. Reversion to Portuguese turpentine seems to have alleviated the problem.     

Effect of basement membrane entactin on epidermal cell attachment and growth

A preparation of laminin and entactin (Matrix), extracted from the basement membrane of the murine cell line M1536-B3 was used to evaluate the effect of entactin on epidermal cell attachment and growth in culture. Cell growth on Matrix was significantly higher than on laminin or plastic, in the presence or absence of serum. In attachment assays, the attachment of cells to laminin (137% of control) or to Matrix (158% of control) was significantly higher when compared with plastic (p less than 0.01), and the attachment to Matrix was higher than to laminin (p less than 0.05). Varying the amount of laminin or Matrix used as a substratum showed each enhanced cell attachment to the same maximum value (approximately 50% attached cells or 160% of control), but maximal attachment was achieved with lower amounts of Matrix (15 micrograms Matrix vs 15-30 micrograms laminin, p less than 0.05). Inhibition studies with anti-entactin and anti-laminin antibodies were used to assay the specific contribution of entactin to cell attachment to Matrix. Pretreatment of the substratum with increasing amounts of anti-entactin antibody decreased cell attachment to Matrix in a concentration-dependent manner, with cell attachment to Matrix eventually falling to the same level as that obtained with laminin. There was no effect with anti-entactin on cell attachment to laminin or to plastic controls, and nonspecific rabbit IgG had no effect on any group. Similar experiments were performed using 2 different concentrations of anti-laminin antibody. At a low concentration, anti-laminin antibody decreased attachment to laminin (to a level equivalent to the plastic control). At a higher concentration anti-laminin decreased attachment to Matrix, but to a level that was still greater than the plastic control. The anti-laminin antibody had no effect on attachment to the plastic control and nonspecific rat IgG in equivalent amounts had no effect on attachment to any of the substrata. These results indicate that Matrix, containing laminin and entactin, enhanced cell attachment above the level seen with laminin alone, and that this effect was probably due to the presence of entactin in the Matrix.     

Occupational dermatoses and allergy to metals in Polish construction workers manufacturing prefabricated building units

The incidence of dermatoses and allergy to metals (Cr, Co, Ni) was determined in 1782 workers exposed to cement, waste fly ash and asbestos cement. They were also exposed to reclaimed (used), mineral oils. Dermatitis was found in 23.6% of the subjects, and oil acne in 11.2%. Allergy to chromium was found in 23% of the subjects; the % of definitely positive patch test results (the total of positive +(+) and strongly positive +(+)+ was, however, 8.6%. Allergy to cobalt was found in 13.4% of the subjects examined (definite in 3.1%). Allergy to nickel was found in 2.7% of the subjects (definite in 1.1%). The risks of occurrence of occupational skin disease and allergy to metals in subjects exposed to ash were found to be lower than in subjects exposed to cement, and were similar to those in subjects exposed to asbestos cement. Overall chromium, cobalt and nickel contents in ash and asbestos were higher than in cement. Soluble chromium compound content in ash was lower than in cement from European countries and similar to that in American cement.     

Cross-sensitizations between azo dyes and para-amino compound

Combined sensitizations to different azo dyes, probably based both on true cross-sensitization and on simultaneous positive reactions, have frequently been described. However, since azo dyes are included in the standard series in a minority of countries, the case studies considered comprise, with few exceptions, a small number of subjects. The aim of our study was to investigate cross-reactions between different azo dyes and para-amino compounds in azo-dye-sensitive subjects, to study the clinical aspects of azo dye dermatitis, to assess the relevance of sensitization to azo dyes, and to relate the pattern of cross-sensitizations to the chemical structure of the different dyes. Out of 6203 consecutively tested patients, 236 were sensitized to at least 1 of 6 azo compounds employed as textile dyes, included in our standard series. 107 subjects reacted to Disperse Orange 3 (DO3), 104 to Disperse Blue 124 (DB124), 76 to p -aminoazobenzene (PAB), 67 to Disperse Red 1 (DR1), 42 to Disperse Yellow 3 (DY3), and 31 to p -dimethylaminoazobenzene (PDAAB). Co-sensitizations to para-phenylenediamine were present in most subjects sensitized to DO3 (66%) and PAAB (75%), in 27% and 36% of DR1 and DY3-sensitive subjects, and only in 16% of subjects sensitized to DB124. Apart from the hands and the face, the neck and the axillae were the most frequently involved skin sites. Whereas the involvement of flexural areas was mainly connected with sensitization to DB124, in patients with hand dermatitis and in those working as hairdressers, sensitization to DO3 and PAAB was more frequent. Moreover, in the former patient group, a history of textile dye allergy was most frequently obtained. Out of 33 patients tested with an additional textile dye series, only 5 subjects reacted to anthraquinone dyes. Cross-sensitizations between azo dyes and para-amino compounds can partially be explained on the basis of structural affinities.