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Biomedical subjects

J G de Monchy

Publications and source records attributed to J G de Monchy.

At least 19 recordsLinked to original sources

Adrenergic response in children with asthma on exogenous stimuli.

In asthmatic children it was investigated whether the degree of impairment of the adrenergic response on exogenous stimuli is related to the magnitude of the 24-hour amplitude in airflow obstructions. Urinary-adrenaline and noradrenaline excretion after house dust mite (HDM) inhalation and after exercise was measured. Nine children with (group I), and nine without increased airflow obstruction overnight (group II) and nine age matched healthy children (group C) were included in the study. All patients showed an early obstructive reaction (EOR) after HDM challenge. Six children in group I and five in group II developed an EOR on exercise. A significant increase in urinary adrenaline excretion was observed after exercise in the control group (P < 0.05, values on the control and challenge day being 5.4 +/- 0.9 and 10.0 +/- 1.6 mumol/mol creat.). The same occurred for noradrenaline (P < 0.01, values being 28.2 +/- 2.5 and 49.0 +/- 5.7 mumol/mol creat.). Adrenergic response after both stimuli was impaired in the asthmatic groups, in group I more pronounced than in group II. Values from group I for adrenaline on the control day, HDM and exercise challenge were 6.0 +/- 0.8, 4.7 +/- 0.6, 6.0 +/- 1.0 and for noradrenaline 36.1 +/- 2.7, 27.2 +/- 2.3, 38.4 +/- 4.9 mumol/mol creat., respectively. Values from group II for adrenaline on these days were 5.6 42- 1.0, 3.7 42- 0.6 and 9.0 +/- 1.3 and for noradrenaline 28.3 +/- 3.2, 22.4 +/- 2.5, 41.3 +/- 5.9 mumol/mol creat., respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Age-dependency of sensitization to aero-allergens in asthmatics.

Skin reactivity (intracutaneous test) to histamine and allergens was studied cross-sectionally in a Dutch asthmatic patient population from childhood to old age (4-75 years). It was found that the histamine skin reactivity rose significantly (p less than 0.05) during childhood, was significantly higher in the 10-15-year age group, and was constant between 20 and 75 years of age. The mean wheal index (histamine ratio) of all allergens was constant during childhood, and decreased after the age of 25 for grass pollen and house-dust mite and after the age of 15 for the other allergens. The prevalence of a positive skin test decreased with age, except for grass pollen. During childhood the indoor allergens, cat dander and house-dust mite, were the most important, while after the age of 15 sensitivity to an outdoor allergen, grass pollen, increased markedly. At all ages house-dust mite was the most important allergen. After the age of 25 the prevalence of every allergen declines. The prevalence of a positive skin test to Cladosporium was unexpectedly high in childhood (10-40%). It can be concluded that the prevalence of a positive skin test declines with age, except for grass pollen. The degree of sensitization in asthmatics peaked in the age groups between 20 and 40 and sensitivity to indoor allergens developed earlier than sensitivity to outdoor allergens.

Adolescent

Comparison of histamine and acetylcholine for use in bronchial challenge testing in atopic and nonatopic subjects with chronic airways obstruction: a review of 180 cases.

A retrospective study was performed to evaluate the diagnostic yield for bronchial hyperresponsiveness from histamine and acetylcholine challenge tests. The records of 180 cases from the last 10 years were analysed. They were selected because their hyperresponsiveness to inhaled histamine or acetylcholine was equal or less than 32 mg.ml-1. Increasing doses of histamine and acetylcholine were given up to a maximum of 32 mg.ml-1 according to the method of de Vries et al. [3]. The challenges were accomplished on two separate days. The provocative dose of agonist causing a 20% fall in FEV1 (PC20) was noted. The interrelationships between smoking history, objective markers of allergy, patient's complaints, histamine and acetylcholine responsiveness were examined. Separate statistical analyses are presented for atopic and nonatopic subjects with chronic airways obstruction. More subjects had a measurable PC20 with acetylcholine than with histamine (43 vs. 16 subjects, p < 0.0001). Using the chi 2 test, the relationship between PC20 histamine and PC20 acetylcholine was similar in smokers and nonsmokers, and in atopics and nonatopics. It is concluded that for an equal molar basis, acetylcholine evokes a higher frequency of bronchus obstruction than histamine in patients.

Acetylcholine

Intestinal permeability in pediatric gastroenterology.

The role of the physiologic barrier function of the small bowel and its possible role in health and disease has attracted much attention over the past decade. The intestinal mucosal barrier for luminal macromolecules and microorganism is the result of non-immunologic and immunologic defense mechanisms. The non-immunologic mechanisms consist of intraluminal factors such as gastric acid, proteolytic activity, and motility and of mucosal surface factors like mucin and the microvillous membrane. The immunologic mechanisms include secretary IgA and cell-mediated immunity. Both types of mechanism are not completely mature at birth. Maturation of this barrier is not finished before the 2nd year of life. One of the aspects of the mucosal barrier function can be estimated by the intestinal permeability (IP) for macromolecules. We use the differential sugar absorption test (SAT), in which the ratio of urinary excretion of a relatively large molecule, lactulose, is compared with that of a relatively small molecule, mannitol, after oral ingestion. Although the small intestine is permeable to certain macromolecules in normal developmental conditions, an increased IP could be involved in the pathophysiology of several diseases, including infectious diarrhea, food allergy, celiac disease, and Crohn's disease. It can be concluded that IP, as measured with the SAT, reflects the state of the mucosal barrier and is altered in several gastrointestinal diseases. The SAT is a non-invasive IP test that can be of diagnostic help to demonstrate alterations in the small-mucosal barrier function and may be useful to evaluate therapeutic interventions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Allergen-induced changes in adenosine 5'-monophosphate bronchial responsiveness: effect of nedocromil sodium.

Bronchial hyperresponsiveness to adenosine 5'-monophosphate (AMP) was studied after allergen challenge in allergic asthmatic patients. Measurements were made with and without nedocromil sodium pretreatment. Nedocromil sodium inhibited both the early and late asthmatic reactions (P < .01). After allergen challenge a significant decrease in PC20 AMP from 12.2 mg/mL to 4.47 mg/mL (P < .05) at three hours was found, returning almost to baseline values: 10.85 mg/mL (P > .05) at 24 hours. Nedocromil sodium, 6 mg, given before allergen challenge prevented the increased responsiveness to AMP at three hours [PC20 10.12 mg/mL (P < .05)], but caused a decrease in PC20 AMP at 24 hours to 6.32 mg/mL (P < .05). Desensitization of the adenosine receptor during the late asthmatic reaction, which is prevented by nedocromil sodium, may explain the lack of increased responsiveness at 24 hours. AMP may play a physiologic role in allergen-induced late phase reactions.

Adenosine Monophosphate

[Consensus food hypersensitivity].

Approximately 500 allergists, dermatologists, ENT specialists, paediatricians, general practitioners, pulmonologists and dietitians attended a consensus meeting about food hypersensitivity in September 1990 in Utrecht. At this meeting the clinical manifestations, mechanisms, diagnosis and treatment were discussed. Consensus was reached about the use of terminology such as food allergy (defined as immunologically mediated), intolerance (non-immunological) and aversion (psychological). However consensus was not reached on all points; there was much discussion on the role of food allergy in atopic dermatitis. During the meeting the opinions of the different health care professionals appeared to concur.

Allergens

The effect of nedocromil sodium on the early and late reaction and allergen-induced bronchial hyperresponsiveness.

Bronchial hyperresponsiveness (BHR) to methacholine was studied in 14 patients with asthma and five healthy control subjects, with and without pretreatment with nedocromil sodium, 3 and 24 hours after allergen challenge. Eleven patients demonstrated a dual asthmatic response. A significant decrease in the provocative concentration causing a 20% fall in FEV1 was found from a geometric mean starting value of 1.18 mg/ml on the control day to 0.24 mg/ml (p less than 0.001) and to 0.17 mg/ml (p less than 0.001) 3 and 24 hours after allergen challenge. A significant correlation was observed between the increased BHR at 3 hours and the magnitude of the late response (r = -0.57; p less than 0.05). Nedocromil sodium (6 mg) significantly inhibited the increase in BHR, 1 mg/ml (p less than 0.001) at 3 hours and 0.50 mg/ml (p less than 0.001) at 24 hours. Nedocromil sodium shifted the severity of the early allergic reaction (EAR) from mean -34.8% to -6.9% and inhibited the later allergic reaction (LAR) from -30.5% to +0.4% (p less than 0.005). From the study can be concluded that nedocromil sodium inhibits the EAR and LAR and the allergen-induced increase in BHR. The inhibitory effect of nedocromil sodium on the LAR may be related to its ability to inhibit the increased BHR before the development of the LAR.

Allergens

Effects of inhaled budesonide on spirometric values, reversibility, airway responsiveness, and cough threshold in smokers with chronic obstructive lung disease.

Inhaled corticosteroids are known to reduce respiratory symptoms and airway responsiveness in allergic patients with asthma. The aim of the present randomised, double blind study was to assess the effect of eight weeks' treatment with inhaled budesonide in non-allergic smokers with chronic obstructive lung disease. Twenty four subjects (23 male) entered the study. Their ages ranged from 40 to 70 (mean 57) years, with a mean of 35 (range 9-80) pack years of smoking; the mean FEV1 was 53% (range 32-74%) predicted and geometric mean PC20 (histamine concentration causing a 20% fall in FEV1) 0.96 (range 0.07-7.82) mg/ml. After a two week washout, single blind, placebo period, 12 patients were allocated to treatment with budesonide 1600 microgram/day and 12 to placebo for eight weeks. The only additional drug to be taken was ipratropium bromide "if needed." Twenty one patients completed the study, 10 in the budesonide group and 11 in the placebo group. The standard deviation of the difference between duplicate measurements of PC20 histamine and citric acid cough threshold made two weeks apart was below one doubling dose step. There was a significant reduction in dyspnoea in the budesonide group, but otherwise no change in symptom scores or use of ipratropium bromide over the eight weeks of treatment within or between the two groups. No significant differences in spirometric values, peak expiratory flow, PC20 histamine, or citric acid cough threshold were found between the groups. Although differences were not significant, some of the changes showed a trend in favour of budesonide. Whether a longer observation period would show a significant influence of inhaled corticosteroids in patients with chronic obstructive lung disease remains to be determined.

Administration, Inhalation

Citric acid cough threshold and airway responsiveness in asthmatic patients and smokers with chronic airflow obstruction.

The relation between citric acid cough threshold and airway hyperresponsiveness was investigated in 11 non-smoking patients with allergic asthma (mean FEV1 94% predicted) and 25 non-atopic smokers with chronic airflow obstruction (mean FEV1 65% predicted). Cough threshold was determined on two occasions by administering doubling concentrations of citric acid. Seven of the 11 asthmatic subjects and 14 of 25 smokers with chronic airflow obstruction had a positive cough threshold on both test days. Cough threshold measurements were reproducible in both groups (standard deviation of duplicate measurements 1.2 doubling concentrations in asthma, 1.1 doubling concentrations in chronic airflow obstruction). Citric acid provocation did not cause bronchial obstruction in most patients, though four patients had a fall in FEV1 of more than 20% for a short time on one occasion only. No significant difference in cough threshold was found between the two patient groups despite differences in baseline FEV1 values. There was no significant correlation between cough threshold and the provocative concentration of histamine causing a 20% fall in FEV1 (PC20) histamine in either group. Thus sensory nerves can be activated with a tussive agent in patients with asthma and chronic airflow obstruction without causing bronchial smooth muscle contraction.

Adult

The Dutch hypothesis (chronic non-specific lung disease) revisited.

In 1961 the hypothesis (later referred to as the Dutch Hypothesis (DH)) was put forward that asthma, chronic bronchitis and emphysema should be considered as different expressions of one disease entity, in which both endogenous (host) and exogenous (environmental) factors play a role in the pathogenesis. A hereditary predisposition to develop allergy and bronchial hyperreactivity were considered to be important denominators of disease susceptibility. Complications and complicating diseases would also contribute to the ultimate phenotype of the patient. In the present paper we discuss the relevance of this hypothesis in 1990. Until now it has not been refuted; circumstantial evidence in its favour has accumulated, but formal proof is still lacking. Further research should pay more attention to the genetic aspects of the disease. Arguments are presented against the use of the terms asthma, chronic bronchitis, and emphysema as indicators of disease entities, and in favour of the use of an umbrella-term, e.g. chronic non-specific lung disease (CNSLD), provided that, in addition, every patient is characterized using so-called defining criteria.

Asthma

Increased urinary excretion of the histamine metabolite N tau-methylhistamine during acetylsalicylic acid provocation in chronic urticaria patients.

Seventeen chronic urticaria patients with a history suggestive of acetylsalicylic acid (ASA, Aspirin)-intolerance were challenged with ASA; only 2 patients showed marked clinical reactions. These clinical reactions were accompanied by a significant increase in the urinary excretion of the most important histamine metabolite, N tau-methylhistamine, in comparison with 15 non-responders (p less than or equal to 0.05) and placebo test. These results suggest an involvement of histamine in the pathogenesis of ASA-intolerance in chronic urticaria patients.

Adult

Change in airway responsiveness to inhaled house dust from childhood to adulthood.

Between 1966 and 1969, housedust (HD) inhalation provocation tests were performed in 119 children with asthma. Between 1984 and 1987, 101 of the 119 subjects (85%) were reinvestigated. Thirty-one of these 101 adults who participated in a study on the outcome of childhood asthma were rechallenged with HD after a mean interval of 16 years to establish the change in airway responsiveness to HD from childhood to adult life. In the childhood study in these 31 subjects, six had no response (NAR); six, an early response (EAR); eight, a late (LAR); and eleven subjects, an EAR followed by an LAR (dual asthmatic response [DAR]) to the inhalation of HD. In the second survey, two of the subjects with NAR in the first study had a bronchoconstrictor response to HD. Five subjects with an EAR or an LAR response in childhood had NAR as an adult. The eleven subjects with a DAR during childhood also had a response to HD as an adult; five had an EAR, and six adults again had a DAR. Eleven of the 13 adults (85%) with current respiratory symptoms had a response to HD during the second survey. Although they were symptom free, 11 of the other 18 adults (61%) responded on inhalation of HD. One of the 18 subjects without (6%), and six of the 13 subjects (46%) with current respiratory symptoms, had a provocative concentration of histamine in FEV1 10% of baseline less than or equal to 16 mg/ml. We conclude that, although respiratory symptoms disappear in one half the children with asthma and although adults may believe that they have outgrown their disease, adults still have the potency to respond to inhaled allergens. Most children do outgrow their respiratory symptoms but not the susceptibility of their airways to allergens.

Adult

Allergy in subjects with asthma from childhood to adulthood.

We studied the change from childhood to adulthood in skin test reactivity to house dust, animal dander, grass pollen, and molds, and, in addition, the change in number of blood eosinophils. The study was carried out in a group of 119 children with asthma, aged 6 to 14 years first observed between 1966 and 1969. In the present study, 101 subjects (85%) were reinvestigated after a mean period of 16 years; 43% had current symptoms. Skin test reactivity to all allergens and the number of subjects with positive skin tests to more than one allergen increased from childhood to adulthood. Subjects with allergic rhinitis (38%) had a higher number of positive skin tests to grass pollen in both childhood and adulthood than subjects without allergic rhinitis. Fifty-three children and 10 adults had atopic dermatitis. Atopic dermatitis occurred with equal frequency in children who did and in children who did not have current symptoms later in life. No differences in skin test reactivity to allergens were found between smoking and nonsmoking subjects. Although the smoking period was relatively short, smoking was correlated with eosinophilia in adulthood. The mean number of eosinophils decreased significantly between the first and second survey. The outcome of childhood asthma as defined by current symptoms was not predicted by skin reactivity to allergens, eosinophilia, atopic dermatitis, or allergic rhinitis in childhood.

Adolescent

Clinical assessment after a life-threatening attack of asthma; the role of bronchial hyperreactivity.

Between 1973 and 1986, 19 patients were treated on 21 occasions for life-threatening attacks of asthma. Twelve times mechanical ventilation was needed. None of the patients died. Most of the patients had been recognized as severely asthmatic before the life-threatening attack. Thirteen out of the 19 patients had previously been admitted with a severe asthmatic attack. All patients, except one, were already using maintenance treatment, and 17 had previously been referred to a pulmonologist. During follow-up the bronchial obstruction was, in most cases, fully reversible while using a rather extensive maintenance treatment (maximum forced expiratory volume in one second (FEV1), 69-138% of predicted). Recently, 17 of the 19 patients were reinvestigated, while in stable phase. The patients who had been mechanically ventilated were significantly more sensitive to inhaled histamine than the patients who had not been mechanically ventilated. This was not explained by any difference in basal FEV1 % pred or dosage of corticosteroids. A very low provocation concentration of histamine producing a 20% fall in FEV1 (PC20) may indicate the risk of a severe, life-threatening attack of asthma.

Acute Disease

Precipitating antibodies and positive skin tests in workers exposed to airborne antigens from a contaminated humidification system.

Precipitating antibodies and positive skin tests to antigens from a contaminated humidification system in a synthetic carpet yarn plant were tested in a group of exposed (n = 66) and non-exposed (n = 45) workers. The first investigation was carried out in 1979 shortly before hygienic actions to reduce exposure had been taken. In 1981 and 1985 they were repeated. The significant difference between the positive skin reactions and of positive serology (4 or more lines), observed in 1979 between the exposed and non-exposed population, was not found in 1981 and 1985. In 1979 the differences were the most pronounced in the non-smoking individuals. However, even in that category the significant difference disappeared in 1981 and 1985. A positive skin test in 1979 did not increase the chance of having a positive skin test during repeat investigations. In serology this was only the case when the positive criterion was lowered to three or more lines. This study demonstrates that, in the absence of a quantitative analysis of airborne antigens, skin tests and serology may be helpful in obtaining an estimation of antigenic contamination of the air and subsequent sensitization on a group level. However, these tests are less appropriate when used in an individual health surveillance program at this type of nonspecific antigen exposure.

Adult

Cellular and humoral observations in a patient with allergic bronchopulmonary aspergillosis during a nonasthmatic exacerbation.

A patient is described with an asymptomatic exacerbation of allergic bronchopulmonary aspergillosis (ABPA), clinically characterized by pulmonary infiltrates, with absence of obstructive reactions and a short period of hemoptysis 2 weeks before hospitalization. Cell counts and antibody concentrations were measured in serum, and bronchoalveolar fluid (BAF) samples and values were compared with data from previous periods of symptomatic exacerbations. During the asymptomatic exacerbation, concentrations of antibody to Aspergillus fumigatus, total IgE, and precipitating antibodies were elevated in peripheral blood. No quantitative differences in specific antibody concentrations (IgE, IgG, IgA, and IgM) against A. fumigatus were found between sera from symptomatic and asymptomatic periods of ABPA. In contrast to observations in the serum, protein concentrations in BAL fluid were normal during the asymptomatic period, whereas high concentrations were found during the symptomatic phases. Local antibody concentrations (in BAF) were characterized by high levels of IgA antibodies against A. fumigatus. During asymptomatic and symptomatic phases, eosinophils were elevated in peripheral blood, in sputum, in BAF, and highly elevated in tissue biopsy specimens. Activated eosinophils were found, as indicated by the presence of light-density cells in the circulation and monoclonal antieosinophil cationic protein binding to bronchoalveolar lavage eosinophils. In contrast to the symptomatic phase of ABPA in 1980, demonstrating aspecific airway reactivity to several pharmacologically active substances, no such hyperreactivity was found during the asymptomatic phase of ABPA in 1986. It is proposed that the asymptomatic infiltrative phase of ABPA is an intermediate stage that can develop into a symptomatic phase after prolonged and intensified infiltration of eosinophils. Mediators from the inflammatory cells may be involved in the induction of bronchial hyperresponsiveness. After induction of this hyperreactive stage of the airways, additional liberation of mediators from either eosinophils and/or mast cells will lead to a symptomatic (obstructive) phase of ABPA.

Adult