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R Brehler

Publications and source records attributed to R Brehler.

At least 19 recordsLinked to original sources

Molecular and immunologic characterization of new isoforms of the Hevea brasiliensis latex allergen hev b 7: evidence of no cross-reactivity between hev b 7 isoforms and potato patatin and proteins from avocado and banana.

BACKGROUND: Hev b 7 is a Hevea brasiliensis latex allergen with sequence identities of 39% to 42% to patatins recently identified as potato allergens. The complementary DNAs encoding 2 different Hev b 7 isoforms were previously reported. OBJECTIVE: The aim of this study was to determine the sequence variation of Hev b 7 and to compare the IgE reactivity of individual isoforms in vitro and in vivo. A further objective was to evaluate possible cross-reactivities between Hev b 7 and patatins and proteins from banana and avocado. METHODS: An H brasiliensis lambda ZAP complementary DNA (cDNA) library was screened with use of a Hev b 7 cDNA probe. Four Hev b 7 isoforms were produced in recombinant form and their IgE-binding capacities were compared. IgE immunoblot inhibitions and ELISA inhibition assays were used to investigate the possible cross-reactivity between Hev b 7 and recombinant potato patatin and proteins from avocado and banana. RESULTS: Two new isoforms, S2 and D2, were identified by sequencing 32 cDNA clones with full-length coding regions. All 4 recombinant isoforms displayed esterase activity and identical IgE-binding capacities. The new isoforms S2 and D2 were evaluated in skin prick tests and provoked responses equivalent to natural Hev b 7. No cross-reactivity was observed between Hev b 7 isoforms and potato patatin and proteins from avocado and banana. CONCLUSIONS: All 4 recombinant Hev b 7 isoforms have equivalent IgE-binding capacity and therefore represent suitable reagents for the development of in vitro and in vivo diagnostic tests. Hev b 7, patatins, and their homologs appear not to contribute to cross-reactivity in the latex-fruit syndrome.

Adult

Helicobacter pylori as a possible bacterial focus of chronic urticaria.

BACKGROUND: Chronic urticaria is one of the most frequent skin diseases. Its cause, however, remains unsolved in a large number of cases. Recent investigations pointed to a potential role of Helicobacter pylori infection of the upper gastrointestinal tract as a possible causative agent in chronic urticaria. OBJECTIVE: The aim of this study was to examine the effect of a 14-day eradication therapy on chronic urticaria. METHODS: Thirty patients with chronic urticaria and confirmed H. pylori infection were treated with amoxicillin and omeprazole. Follow-up was conducted over a period of 6 months concerning eradication of H. pylori and remission of urticaria. RESULTS: Only 8 out of 30 patients (26.7%) showed clinical improvement or disappearance of their urticarial symptoms. CONCLUSION: Though our results do not support the preliminary data of previous studies, the role of H. pylori as a possible bacterial focus of chronic urticaria has to be further investigated.

Adult

[Hyperhidrosis].

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Diagnosis, Differential

cDNA cloning of the 43-kDa latex allergen Hev b 7 with sequence similarity to patatins and its expression in the yeast Pichia pastoris.

IgE-mediated hypersensitivity to latex proteins present in health care products, particularly in latex gloves, has become an important public health problem in recent years. We purified natural Hev b 7, a 43-kDa patatin-like allergen from the latex of Hevea brasiliensis and determined several internal peptide sequences. A heterologous hybridization probe of a patatin gene of potato, to which these peptides could be aligned best, was used to screen a latex cDNA library. The cDNA encoded an acidic protein of 388 amino acids with a molecular mass of 42.9 kDa. The deduced amino acid sequence had 39-42% identity to patatins from Solanum tuberosum. The purified recombinant Hev b 7 expressed in the yeast Pichia pastoris displayed, similarly to patatins from S. tuberosum, esterase activity. Both natural and recombinant Hev b 7 were recognized by IgE from sera of latex-sensitized allergic individuals. In contrast to patatins from S. tuberosum and Nicotiana tabacum, natural Hev b 7 lacked an N-terminal leader peptide for targeting to the endoplasmatic reticulum and was not glycosylated. These results establish the 43-kDa patatin-like protein as a latex allergen and raise the possibility of different cellular localization and function compared to S. tuberosum patatins.

Allergens

Reduction of latex aeroallergens and latex-specific IgE antibodies in sensitized workers after removal of powdered natural rubber latex gloves in a hospital.

BACKGROUND: Respiratory symptoms of natural rubber latex (NRL) allergy in health care workers (HCWs) have been reported in rooms with a detectable allergen load. Preventive measures have been proposed to reduce the risk of NRL sensitization. OBJECTIVES: Eliminating powdered NRL gloves from the workplace and giving NRL-free material to sensitized workers has been among proposed preventive measures. To appraise the success of such procedures among HCWs, a prospective study was carried out. METHODS: Sensitization of HCWs to NRL was determined by skin prick tests and measurements of specific IgE antibodies. NRL allergen concentrations in room air were measured before and after substitution of powdered NRL gloves with powder-free or synthetic gloves in different departments of a hospital and determined by a competitive inhibition immunoassay. RESULTS: The prevalence of HCWs with positive skin prick test responses and NRL-specific IgE-positive HCWs was 8% (n = 7) among the 90 examined staff members before the intervention started. All 7 reported glove-related allergic symptoms. Six of 7 sensitized subjects had a significant decrease of latex-specific IgE antibody concentrations during follow-up examinations in April and September 1997 (P <.003). Within 24 hours after substitution took place, NRL aeroallergen levels (up to 49.9 ng/m3) fell below the detection limit in areas with synthetic gloves or powder-free NRL gloves alike. Use of asthma medication and antiallergic drugs could be discontinued by 2 HCWs with NRL-related respiratory tract symptoms. CONCLUSIONS: Our results demonstrate that elimination of powdered NRL gloves is a useful device in reducing aerogen NRL allergen loads below the detection limit and permitting sensitized or allergic personnel to remain on the job.

Adult

Cross-reactivity between Ficus benjamina (weeping fig) and natural rubber latex.

The importance of hypersensitivity to Ficus allergens is reported. Cross-sensitization between fig (Ficus carica), weeping fig (F. benjamina [Fb]), and natural rubber latex (NRL) was confirmed by RAST inhibition. We performed skin prick tests with fresh Fb tree sap and NRL extracts in 346 consecutive patients and in 151 patients with immediate-type hypersensitivity to NRL. Total serum IgE and IgE antibodies to NRL and Ficus spp. were analyzed in sera. By the RAST-inhibition method, we studied cross-reactivity among latex, fig, and weeping fig. Sensitization to Fb was diagnosed in 23 of the 346 consecutive patients, and the simultaneous presence of latex-specific IgE was highly significant. Of 151 NRL-allergic patients, 35 were also sensitized to Fb. Cross-reacting IgE antibodies recognizing latex and Ficus allergens were demonstrated by RAST inhibition. The present study reinforces the importance of Fb as an indoor allergen. Cross-reacting IgE antibodies to NRL and Ficus spp. allergens are frequently found in the sera of atopic patients. Development of commercially available standardized extracts for skin tests is urgently necessary.

Adolescent

Tree-pollen allergy is efficiently treated by short-term immunotherapy (STI) with seven preseasonal injections of molecular standardized allergens.

The efficacy and tolerance of short-term immunotherapy (STI) by seven preseasonal injections of tree-pollen allergens (ALK7 Frühblühermischung) was investigated in a double-blind, placebo-controlled, multicenter study with 111 rhinoconjunctivitis patients. Nasal and bronchial symptoms simultaneously analyzed, and nasal symptoms as a single end point, but not the overall score of nasal, bronchial, and conjunctival symptoms, showed a significantly lower increase with STI during birch-pollen exposure (both P=0.033, n=105, Mann-Whitney U-test). However, a selective analysis with patients from centers with high recruitment figures (n> or =10 patients, n=29 STI, n=32 placebo) showed a significantly lower increase of nasal, bronchial, and overall symptom score (STI 11.0 vs placebo 18.0, P=0.001, U-test). STI had equidirected effects on conjunctival, nasal, and bronchial symptoms analyzed as multiple end points, although conjunctival symptoms were not significantly different as a single end point. The seasonal increase in drug use was reduced by 62% in the STI group compared with placebo (P=0.032, t-test). Specific IgG4 increased only after STI (P<0.001); IgE was not significantly different. Eosinophil cationic protein remained unchanged with STI, but significantly increased with placebo in the pollen season (P=0.003). STI was well tolerated. In conclusion, STI was shown to be efficacious and safe for the treatment of patients with tree-pollen rhinoconjunctivitis.

Adolescent

Glove powder affects skin roughness, one parameter of skin irritation.

Most patients with immediate-type-hypersensitivity to natural rubber latex (NRL) give a history of hand eczema. Susceptibility to allergens is increased by irritant hand eczema due to damage to the skin barrier. Therefore, especially for employees in medical or paramedical professions, reduction in skin irritation is of importance. The present study reports the effect of glove powder on skin roughness, one feature of skin irritancy. Skin replicas, performed before and after wearing different types of gloves, were evaluated by laser profilometry. Significant alteration of skin roughness was evident and determined by different factors. Use of unpowdered Biogel gloves on prepowdered hands results in an increase in skin roughness, in contrast to the use of Biogel gloves on hands without any pre-application. On the other hand, powdered Manex neoderm gloves show no influence on the skin structure, whereas powdered Peha taft gloves also increase the roughness of the skin. Other potential candidates causing skin morphology alteration could be the glove pH, rubber chemicals with irritant potential and other characteristics of gloves, which are already under investigation.

Adult

Recent developments in the treatment of atopic eczema.

Atopic eczema remains a therapeutic challenge. However, new developments in the understanding of the pathogenesis of this complex disease have prompted new therapeutic strategies. This review focuses on recently described treatment modalities for atopic eczema that are currently available or under investigation. The effectiveness of phototherapy, cytokines, and immunosuppressive drugs is evaluated. In addition, some new and promising but still experimental approaches are discussed.

Cytokines

Neutrophilic hidradenitis induced by chemotherapy involves eccrine and apocrine glands.

Neutrophilic eccrine hidradenitis is a self-limited inflammatory dermatosis primarily induced by chemotherapeutic agents. We report the case of a 43-year-old patient treated with cytarabine, daunorubicin, and thioguanine for acute myelogenous leukemia who developed painful, red nodules in both axillae on the third day of chemotherapy. The lesions healed spontaneously without sequelae and reappeared once when chemotherapy was readministered. Histologic examination and immunohistochemical staining for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), and S100 revealed necrosis of eccrine and apocrine glands. As a secondary event, neutrophils, histiocytes, and lymphocytes of T and B cell types were infiltrating the glandular coils. Electron microscopic examination confirmed the presence of severe cellular degeneration of the secretory epithelia and coiled sweat ducts. Ultrastructural features and absence of labeling with a nick-end labeling technique were consistent with a non-apoptotic mode of cell death. Our findings strongly suggest a cytotoxic effect of chemotherapeutic agents as accumulated in the secretory epithelia of sweat glands. Distal ducts and myoepithelial cells remained intact and may account for rapid regeneration of the glandular structures after discontinuation of chemotherapy. In view of the involvement of both eccrine and apocrine glands, we suggest the term neutrophilic hidradenitis, which is part of the spectrum of drug-associated sweat gland reactions.

Adult

"Latex-fruit syndrome": frequency of cross-reacting IgE antibodies.

An association between allergies to latex proteins and to various foods has been reported and confirmed by RAST and immunoblotting inhibition. However, no significant data had been collected on the frequency of specific IgE antibodies to fruits in these patients and the frequency of a history of fruit intolerance. Serum samples of 136 patients with well-documented, clinically relevant, immediate-type hypersensitivity against latex proteins were analyzed for IgE antibodies against a panel of different fruits. Patient history of food intolerance was documented by a standardized questionnaire. Fruit-specific IgE antibodies were detected in 69.1% of serum samples. Cross-reacting IgE antibodies recognizing latex and fruit allergens (papaya, avocado, banana, chestnut, passion fruit, fig, melon, mango, kiwi, pineapple, peach, and tomato) were demonstrated by RAST-inhibition tests. Of our patients, 42.5% reported allergic symptoms after ingestion of these fruits and a total of 112 intolerance reactions were recorded. However, fruit-specific IgE antibodies were detected only in serum samples from 32.1% of the patients who perceived symptoms due to these fruits. Thus, serologic tests seem to be of low significance for prediction o food allergy in latex-allergic patients.

Adolescent

IgE-mediated hypersensitivity to latex in childhood.

A total of 267 children scheduled to receive anesthesia during a surgical, neurosurgical, or orthopedic intervention were investigated. IgE antibodies against latex were detected in serum samples of 6.4% (17/267 children) of the patients. The most important difference between sensitized and nonsensitized children was the number of surgical interventions in the past. The median of surgical interventions was 1.0 in the nonsensitized group of children and 3.0 in the sensitized group. Only 0.9% of the children with up to two surgical interventions and 34.1% with three or more procedures were sensitized to latex. Only one of the sensitized children developed intraoperative anaphylaxis during intervention after our investigation. We conclude that children with a history of three or more surgical interventions have a high risk of sensitization to latex proteins. Nevertheless, the predictive value of IgE antibodies against latex for development of anaphylaxis during anesthesia seems to be low.

Adolescent

Contact urticaria due to rubber chemicals?

Contact urticaria due to gloves is mostly related to immediate-type allergy to natural rubber latex (NRL), and rarely due to rubber chemicals. We report the results of prick tests with rubber chemicals carried out on 75 latex-allergic patients. Clinically relevant hypersensitivity was not observed in our patient collection. Thus, we conclude that contact urticaria due to rubber chemicals is a very rare finding in latex-allergic patients, but has to be considered in patients with contact urticaria due to synthetic rubber gloves, as well as in patients with contact urticaria due to NRL gloves but no latex allergy. Therefore prick tests with rubber chemicals are unnecessary in the routine diagnostic assessment of latex-allergic patients.

Adolescent

Glove powder--a risk factor for the development of latex allergy?

Studies are described which compare the prevalence of sensitisation against latex proteins in medical personnel in different hospitals. The objective of these studies was to find out whether the use of powdered or unpowdered gloves could be related to the prevalence of latex allergy. Employees of one of the investigated hospitals (Germany) were using only powdered latex gloves, and in the other two hospitals (Great Britain) low protein powder-free latex gloves were used. Methods by which latex allergy can be avoided are suggested.

Allergens

[Ficus benjamina allergy].

We report the case of a 48-year-old patient suffered from asthma and conjunctivitis caused by an immediate type allergy to weeping fig (Ficus benjamina). By RAST inhibition test we could demonstrate that IgE antibodies react with allergens of fig; however our patient tolerated figs in oral provocation test. Sensitization to latex proteins reported to be cross reactive to Ficus species was not found. Ficus benjamina allergens represent relevant indoor allergens. A standardized allergen extract for skin testing is not yet available. Allergen specific IgE is mostly found in patients with strongly positive prick test results using the native sap of the tree. In 12 of 64 latex allergic patients we found simultaneous sensitization to weeping fig, so that cros-sensitization has to been considered in patients with IgE-mediated sensitization to latex.

Asthma