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D Vervloet

Publications and source records attributed to D Vervloet.

At least 181 records · Page 10Linked to original sources
PubMed1988

[Allergy to Hymenoptera. Incidence and degree of public knowledge].

The prevalence of systemic reactions to hymenoptera stings in adults is unknown. To elucidate this point we interviewed 2.067 persons aged from 20 to 60 years who attended a medical screening centre. We asked them whether they had ever experienced a reaction this kind, what they knew about it and what they did, and we performed skin tests to hymenoptera venoms in those who gave a positive answer. The proportion of subjects who had had at least one type of systemic reaction after being stung was 1.2 per cent; 0.9 per cent of the subjects had both a history of reaction and a positive skin test. This figure is in keeping with those obtained in surveys carried out among children, but is does not tally with the mortality figures which probably are grossly under-estimated. The general population is not adequately informed of possible systemic reactions to hymenoptera stings, so that people often fail to consult, and the practitioners themselves do not advise their patients to see an allergologist for evaluation. Thus, adequate information of the general population and the physicians is badly needed.

Adult↗
PubMed1988

Atopy and anaphylactic reactions to suxamethonium.

Muscle relaxants are widely used for general anesthesia and may be responsible for IgE-dependent anaphylactic reactions (AR). A controversial issue in the field of drug allergy is whether ARs are more frequent or severe in atopic subjects. Thus, we performed a case-control study comparing the distribution of various clinical and biologic signs of atopy. The case group included 32 patients with a history of AR to suxamethonium, the most commonly used muscle relaxant. The control group included 128 subjects, matched to the case group according to age, gender, and socioeconomic status. The case group consisted mainly of young and middle-aged women. Distribution of symptoms suggestive of atopy and of skin tests and specific IgE to common aeroallergens was similar in both groups. In contrast, total serum IgE level was much higher in the case group, suggesting the presence of specific IgE against suxamethonium or other drugs. Thus, despite previous studies in the literature, atopy is not a risk factor for the occurrence of anaphylactic reactions to muscle relaxants. As AR to suxamethonium is a pure model of an IgE-dependent drug allergy, our data do not support a relationship between atopy and allergic drug reactions.

Allergens↗
PubMed1988

Epidemiology of asthma in western Europe.

Asthma deaths are uncommon, but have recently increased in some countries due to problems in the management of the disease. Morbidity rates show large variations, which can be attributed to differences in defining the disease, but also to genuine variations, with a trend towards less asthma in northern Europe. It has been suggested that allergic diseases as a whole, and asthma in particular, may exhibit an upward secular trend. Risk factors include a genetic background and environmental triggering factors. The importance of genetic factors is illustrated by family studies and by extreme prevalence rates observed in some communities. Environmental factors include rapid air pollution variations which act as a trigger for asthma attacks. However, at levels currently prevailing in western Europe, air pollutants do not induce a higher incidence of asthma. Altitude generates a gradual decrease in Dermatophagoides, thus explaining both the clinical improvement in asthmatics living in altitude and a lower prevalence of asthma in populations born and living there. Among the other aero-allergens, grass pollens plays a major role in spring, elicitating asthma attacks. Some natural allergens transformed by man (castor bean, soja) can be responsible for asthma epidemics.

Air Pollution↗
PubMed1988

Sensitization to aluminium by aluminium-precipitated dust and pollen extracts.

We report 2 cases of aluminium sensitivity in adults. Each time, the means of sensitization was the inoculation of aluminium-precipitated pollen or dust extracts for hyposensitization. We conclude that aluminium allergy is not exceptional and that in these cases one can observe allergic reactions to the Finn Chamber tests.

Adult↗
PubMed1988

Asthma and allergy to house-dust mites in populations living in high altitudes.

Do subjects living in high altitude where house-dust mites are known to be uncommon exhibit a lower prevalence of asthma and allergy to house-dust mites? To answer this question, we compared the prevalence rates of asthma and skin reactions to house-dust mites in two towns with contrasted environments: Marseille, located on the seashore, and Briançon, 1350 m in altitude. The study population consisted of a random sample of 4,008 people in Marseille and 1,055 people in Briançon. All subjects received a home questionnaire, and a sample of patients and asymptomatic subjects had a skin-prick test evaluation. The cumulative prevalence of asthma was equal to 4.1 percent in Marseille and 2.4 percent in Briançon, a difference which was significant (p = 0.01). The prevalence of positive skin tests to housedust mites in asymptomatic subjects was equal to 27.5 percent in Marseille and 10.2 percent in Briançon (p less than 0.001). This study supports the hypothesis that exposure to environmental factors may have a major influence on developing allergic diseases.

Adult↗
PubMed1988

[Does common asthma show intercritical functional anomalies?].

During an epidemiological survey conducted in 1985, we performed spirometric examinations in a group of 133 asthmatic subjects and a group of 168 control subjects. After standardization for sex, height and age, mean FEV1 values were lower in asthmatics than in control subjects and decreased when the frequency of asthma attacks increased. Thus, from observations gathered in asthmatics identified by a questionnaire during a field study, we can confirm previous conclusions drawn from outpatients clinics: most of the time, asymptomatic asthmatics demonstrate an airflow limitation.

Adult↗
PubMed1988

[Heredity of asthma].

To compare the heredity of asthma among families of intrinsic, extrinsic and control subjects, we have studied the siblings and offsprings of the 3 groups of subjects (using a standardized questionnaire). The results shown that asthma was genetically transmitted but the clinical manifestations appeared later among the relatives of intrinsic than among the relatives of extrinsic asthmatic patients.

Asthma↗
PubMed1988

[The role of alpha-amylase in baker's asthma].

We report a case of asthma in a baker provoked by an additive which is generally used in bread making, namely alpha-amylase, an extract of Aspergillus oryzae. Skin tests to alpha-amylase were positive in a concentration of 0.1 micrograms/ml. Specific IgE was detected to this enzyme. A provocation test to alpha-amylase was positive with a fall of the FEV1 of 42%. Provocation tests to flour gave a negative immediate and delayed reaction. Progress was made towards the disappearance of symptoms after several months of avoiding the allergen. This observation has enabled us to show the specificity of the allergy to alpha-amylase, a glycolytic enzyme, coming in the group of occupational diseases n. 63 (asthma due to lyophilised enzymes) whereas baker's asthma is at n. 66.

Adult↗
PubMed1988

[Prevention of infections in chronic bronchitis using vaccination and/or immunomodulation].

Polyvalent antimicrobial vaccines have been widely used in chronic bronchitis for nearly fifty years without their effect or mechanism of action always being well understood. The polysaccharide vaccines, in particular pneumococcal, are better defined chemically and in their mode of action. However, it does not seem that ordinary chronic bronchitis is a good indication for these vaccines. The immunomodulators, extracts of the cell wall of certain bacteria, are aimed at increasing the host's defence capacity in a non-specific manner. The addition of ribosomes may favour specific and non-specific immunomodulation. Certain vaccines have shown their efficacy in reduction of infective episodes in chronic bronchitis. However, other studies ought to be undertaken to obtain purified products which are not toxic and are yet more effective. Finally, it is necessary to have better knowledge of the mode of administration and of the doses administered corresponding to the optimal efficacy of the vaccines.

Adjuvants, Immunologic↗
PubMed1988

[Is there an urban factor in asthma and allergy?].

To evaluate if an "urban factor" could be responsible for an increase of asthma and allergic diseases in developed countries, we compared prevalence rates for these conditions in adults living in urban and rural settings. The urban group consisted of 4,008 adults, randomly selected from the 16 districts of the city of Marseille; the rural group consisted of 1,789 adults, representing 85% of the target population living in a small residential town, Trets. The protocol included, after a mass media information, home-visits by public health physicians. These physicians asked a short standardized questionnaire to all adults 18 to 65 years old. Then, in a subgroup of, hay-fever patients, they performed skin tests to grass pollens. The standardized prevalence rates of asthma and related symptoms, and hay fever, was very similar in both settings. Thus, this study does not support the hypothesis that there is a urban factor in asthma and allergic diseases. In the literature, several studies point out a higher prevalence of these diseases in an urban setting. But these studies have been performed several years ago, when there was a larger difference in air pollutants concentrations between urban and rural settings.

Adolescent↗
PubMed1987

Analysis of cell structural and functional diversity by combination of micromanipulation and microfluorimetry.

Fluorescent molecules are widely used to study quantitative cell properties, such as density of different antigenic markers or membrane responses to various stimuli. In most cases, studies are done on bulk cell populations with a spectrofluorimeter or at the single cell level with a cytofluorograph. However, only microspectrofluorimetric techniques allow continuous recording of dynamic events undergone by individual cells. The aim of the present report was twofold: first, to describe a methodology easily accessible to cell biologists that allows simultaneous manipulation of single cells and measurements of their fluorescence properties; and second, through this methodology to study quantitative aspects of cell structure and function such as binding of a fluorescein-labeled lectin, transfer of fluorescent molecules between labeled and unlabeled cells brought in close contact, or fluorescence response of individual cells stimulated after being loaded with a potential-sensitive dye. We conclude that the understanding of many aspects of cell structure and behavior requires that individual cells be studied under dynamic conditions and for prolonged periods of time.

Animals↗
PubMed1987

Role of the quaternary ammonium ion determinants in allergy to muscle relaxants.

Anaphylaxis to muscle relaxants appears to be a very useful model to study the IgE-dependent mechanisms of mediator release in humans. The serum IgE binding sites of the drugs appeared to be the ammonium ion determinants. In patients allergic to suxamethonium, one of the most frequently used muscle relaxants for general anesthesia, significant histamine release could be obtained in each case with simple diammonium salts. The length of the chain linking the ammonium groups appears to play an important role. In fact, when the length was less than or equal to 4 A, no significant histamine release could be obtained, whereas the optimal length for histamine release appeared to be greater than or equal to 6 A. Furthermore, muscle relaxants with a rigid backbone between the ammonium determinants (such as pancuronium) are less active than flexible molecules (such as suxamethonium) in initiating mediator release. This study suggests that small divalent molecules can induce anaphylactic shock in sensitized patients and that the length and the flexibility of the chain bearing the haptenic determinants appear to be important factors in the elicitation of mediator release.

Drug Hypersensitivity↗
PubMed1987

Allergy to suxamethonium: persisting abnormalities in skin tests, specific IgE antibodies and leucocyte histamine release.

Twenty-one patients, who had previously experienced an anaphylactic reaction to suxamethonium during general anaesthesia, were selected for this study. Initially, skin tests with muscle relaxants were carried out in the twenty-one patients, detection of specific anti-choline IgE in nineteen, and leucocyte histamine release in seventeen. These three tests were then repeated between 1 year and 4 years after the initial evaluation. In the majority of patients, sensitization to the muscle relaxants persisted for more than 1 year after the anaphylactic reaction. Only three patients out of twenty-one (4%) had negative skin tests when retested 1-4 years later. A reduction in leucocyte histamine release was noticed in one of the seventeen retested patients (6%). Modifications of anti-choline IgE were observed in five of nineteen patients (26%). The persistence of sensitization to suxamethonium may result from repeated stimulation by occasional contacts with quaternary ammonium compounds. This study demonstrates the reliability of skin tests, leucocyte histamine release and detection of anti-choline IgE to diagnose allergic reactions to suxamethonium, even when they are performed a long time after the initial anaphylactic reaction.

Alcuronium↗
PubMed1987

Relationship between skin reactions to common allergens and non-specific bronchial reactivity in young healthy subjects.

In patients with respiratory symptoms, several studies have provided data supporting the hypothesis that there is a casual relationship between allergen exposure and variations in bronchial reactivity. In order to determine if this relationship holds when atopy is defined only on the basis of positive skin tests to common allergens, we compared bronchial reactivity in a group of twelve healthy subjects with positive skin tests and twenty-eight healthy subjects with negative tests. The two groups were comparable in terms of gender, age, smoking habits and family history of atopic diseases. The slopes of the dose-response curves, using airway conductance as an index of response, were similar in the two groups. Thus, in this healthy group of subjects, there was no relationship between skin and bronchial reactivity. It can be hypothesized that, if genetic factors determine bronchial reactivity, such reactivity might not be revealed until skin-test positive subjects have received repeated bronchial stimulation through inhalant allergens.

Adult↗