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Biomedical subjects

K de Vries

Publications and source records attributed to K de Vries.

At least 37 records · Page 2Linked to original sources
PubMed1987

The beta-adrenergic system of non-allergic patients with chronic airflow obstruction and early morning dyspnoea.

Lymphocyte beta-adrenergic receptor function and urinary excretion of catecholamines were measured in eight non-allergic patients with partially reversible chronic airflow obstruction (CAO) and early morning dyspnoea (EMD), and in eight matched healthy control subjects. In order to establish a possible relationship between the early morning dyspnoea and a reduced beta-adrenergic activity, these parameters were measured during the "morning dip" in FEV1 and in the afternoon, when lung function is maximal. No differences were observed for lymphocyte beta-adrenergic receptor characteristics (beta-receptor number, Kd, for 3H-dihydroalprenolol, and cAMP response to isoproterenol) between patients and controls, when determined at 8 AM or at 4 PM. Nor was there a significant circadian variation in these parameters present in both groups. By contrast, the patients showed a significantly reduced urinary excretion of epinephrine and norepinephrine, as measured in four-hourly urine portions collected between 8 and 12 AM and between 4 and 8 PM, respectively. In addition, the urinary excretion of epinephrine showed a significant circadian variation in the patients, which was correlated with the FEV1 (% predicted). Such a relationship was not found for norepinephrine. The results suggest that a (generalized) dysfunction of the beta-adrenergic receptor is not involved in the pathogenesis of CAO or EMD. However, reduced beta-adrenergic receptor stimulation due to decreased levels of catecholamines may contribute to the observed (variation in) airflow obstruction of the patients.

Adult↗
PubMed1986

Phorbol 12-myristate 13-acetate induces beta-adrenergic receptor uncoupling and non-specific desensitization of adenylate cyclase in human mononuclear leukocytes.

Tumour-promoting phorbol esters such as phorbol 12-myristate 13-acetate (PMA) have been reported to modulate beta-adrenergic receptor responses in various cell types, presumably by the activation of protein kinase C. In the present investigation we assessed the effect of PMA on the beta-adrenergic receptor-adenylate cyclase system of human mononuclear leukocytes (MNL). It was found that incubation of MNL with PMA resulted in a time- and concentration-dependent desensitization of isoproterenol-induced adenylate cyclase activity. However, the effect of PMA was not restricted to the beta-adrenergic receptor system, since basal adenylate cyclase activity and histamine-, prostaglandin E1-, 5'-guanylylimidodiphosphate (GppNHp)-, and NaF-stimulated values were also reduced. By contrast, no effect was found on the forskolin-induced adenylate cyclase activity. The inactive phorbol ester, 4 alpha-phorbol 12,13-didecanoate had no effect on adenylate cyclase at all, suggesting that the observed PMA effect was specifically mediated by activation of protein kinase C. The reduced beta-adrenergic response induced by PMA was not associated with a reduced beta-adrenergic receptor number, indicating uncoupling of this receptor from adenylate cyclase. Isoproterenol competition curves for 3H-dihydroalprenolol binding to membranes from untreated and PMA-treated cells demonstrated that the uncoupling was due to a reduced ability of the agonist to promote formation of the guanine nucleotide-sensitive high affinity state of the receptor. The results indicate that PMA may cause desensitization of catecholamine-responsive adenylate cyclase in MNL, and that the major locus of alteration is the guanine nucleotide regulatory protein.

Adenylyl Cyclases↗
PubMed1986

Bronchial hyperreactivity and bronchial obstruction in respiratory viral infection. An attempt to evaluate the relationship.

The aim of this study was to investigate the relation of viral respiratory infection with bronchial hyperreactivity and bronchial obstruction. A viral infection using a live attenuated influenza virus was induced successfully in 10 of 30 patients with chronic obstructive pulmonary disease (COPD) and in 3 subjects without COPD (non-COPD). No significant change in bronchial reactivity and lung function could be found in comparison with the baseline values.

Administration, Intranasal↗
PubMed1986

Class-specific antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. III. Comparative study: IgG, IgA, IgM ELISA titers, precipitating antibodies and IgE binding after fractionation of the antigen.

IgG, IgA and IgM ELISA antibody titers against Aspergillus fumigatus were elevated in sera of patients with aspergilloma and allergic bronchopulmonary aspergillosis (ABPA), showing higher titers for the IgG antibodies compared with the IgA and IgM antibodies. No differences were found between titers of identical antibody classes in the two groups of sera. IgG and IgA ELISA titers were highly specific whereas IgM ELISA showed more unspecific binding of IgM antibodies. Antibodies, as measured by ELISA, studied after fractionation of the antigen into fractions of decreasing molecular weight, showed a preferential binding by the high molecular weight fractions. Precipitating antibodies studied in patient sera did not always correspond with the IgG ELISA titers. IgE antibody binding was observed in all fractions from Sephadex G-100 fractionated components; maximum binding was found with fractions of 28,000-60,000 daltons. The low molecular weight fractions (18,000-less than 5,000 daltons) showed less IgE binding but the quantity of this fraction was higher. The discrepancies noted between the IgG and IgA ELISA titers and the binding of IgM or IgE antibodies indicate that antigenic components may in part differ in the binding of antibody classes.

Antibodies, Fungal↗
PubMed1986

Specific immunological modulation of lymphocyte adenylate cyclase in asthmatic patients after allergenic bronchial provocation.

Adenylate cyclase responses to isoproterenol, histamine, 5'-guanylylimidodiphosphate (GppNHp) and NaF were measured in lymphocyte membranes of allergic asthmatic patients and healthy control subjects, just before and 24 h after inhalation challenge with house dust mite allergen or histamine. In the nonacute phase before the challenges, the adenylate cyclase responses in the cell membranes of the patients were not significantly different from those in membranes of the control subjects. House dust mite challenge caused a significant decrease of all adenylate cyclase responses in the cell membranes of the patients by about 40-50%. By contrast, histamine provocation of the patients had no effect on these parameters, nor was there any effect of both challenges on the adenylate cyclase activity of the control membranes. The results indicate that allergen-induced asthmatic reactions may cause nonspecific refractoriness of lymphocyte adenylate cyclase. Since histamine-induced bronchial obstruction had no effect in the patients, it appears that the adenylate cyclase response is specifically modulated by the allergic process.

Adenylyl Cyclases↗
PubMed1986

Independent influence of reversibility of air-flow obstruction and nonspecific hyperreactivity on the long-term course of lung function in chronic air-flow obstruction.

We evaluated factors that might influence the course of lung function after 2 to 21 yr of follow-up in 81 nonallergic patients with chronic air-flow obstruction (CAO) and considerable lung function impairment (initial forced expiratory volume in one second as a percentage of inspiratory slow vital capacity (FEV1 % VC) ranging from 40 to 55% and increasing less than 15% after the administration of the anticholinergic bronchodilator thiazinamium). A more favorable rate of change in FEV1 was associated with less pack-years of smoking, less nonspecific hyperreactivity, and a higher degree of reversibility of air-flow obstruction, when expressed as the increase in FEV1 as a percentage of the predicted minus prebronchodilator FEV1 value. Nonspecific hyperreactivity and reversibility of air-flow obstruction appeared to influence the decline in FEV1 independently of baseline value of FEV1, both in smokers and ex-smokers. The hypothesis is put forward that regular bronchodilating therapy may be able to prevent deterioration of lung function. However, the possibility that interval therapy may ultimately produce the same results cannot be excluded. It seems to be important to stop smoking, both for the sake of its negative influence on the course of FEV1 and for the fact that a beneficial influence of bronchodilating therapy may become even more apparent.

Adult↗
PubMed1985

Lung function of workers exposed to antigens from a contaminated air-conditioning system.

Following the manifestation of humidifier fever in a number of workers in a carpet yarn texturing plant, a comparative study was begun of a group of workers exposed to fungi from the air-conditioning system and a control group not so exposed. For both group of workers anamnestic data were collected, intracutaneous skin tests were performed, certain lung function parameters were determined, and the presence of antibodies to a number of antigens from the system was tested for. It was found that the group of exposed workers had a significantly higher rate of positive intracutaneous skin test than non-exposed workers. Additionally, their serology was more often positive. Both positive skin test and positive serology were more frequent in non-smokers than in smokers. A positive immediate skin reaction among exposed workers was found to correlate with an FEF25-75 reduction during the working week. A positive delayed skin reaction among exposed workers correlated with a lower FVC prior to the start of the working week than recorded for non-exposed workers. A positive serology in exposed workers did not correlate with a difference in lung function compared with non-exposed workers, nor was there a correlation with a change in lung function in the course of the working week. When humidifier fever is diagnosed, steps should be taken to reduce exposure. It would also appear desirable to keep exposed workers under medical observation and to monitor the subsequent development of their lung function.

Adolescent↗
PubMed1985

Histamine in late asthmatic reactions following house-dust mite inhalation.

In order to investigate the role of histamine in the late asthmatic reaction (LAR) following house-dust mite (HDM) inhalation, we studied, with hourly intervals, urinary N tau-methylhistamine (an important metabolite of histamine) in 14 allergic asthmatic patients before and after broncho provocation with HDM. Four patients showed an early asthmatic reaction (EAR), while 10 patients developed a LAR as well. In the hour following the EAR a significant increase in urinary N tau-methylhistamine was observed as compared to the control day (0.01 less than p less than 0.05). During the LAR no increase of this metabolite was detected in the urine of the patients. Additionally, histamine was measured in broncho alveolar lavage fluid (BAF) obtained from 6 patients during the HDM-provoked LAR and compared to histamine levels in BAF from patients without a LAR, following broncho provocation. In the LAR group higher histamine levels were found than in the other patient and control groups. For the whole patient group no correlation was found between the degree of bronchial obstruction during the LAR and the BAF histamine values. No difference was found in N tau-methylhistamine in BAF between patients with LAR and controls. Thus histamine metabolite studies in the urine failed to provide evidence of involvement of histamine in the LAR, while further data are needed to interpret the results of local sampling in the lung.

Adolescent↗
PubMed1985

The value of laparoscopy in women with chronic pelvic pain and a "normal pelvis".

During the period January 1976--December 1982 laparoscopy was performed on 186 women complaining of pelvic pain of at least 6 months' duration. In all these cases, the routine pelvic examination and other medical and laboratory tests were negative. Laparoscopy revealed pelvic pathology in only 8.2%: in the vast majority (91.8%) entirely normal pelvic organs were seen. Evidence from the literature is compiling as to the psychogenic origin of most cases of chronic pelvic pain. Recently, it has been shown that laparoscopically negative pelvic pain can be relieved or abolished by psychological intervention. Since pathological findings on laparoscopy are of very low percentage and since the pain is psychogenic in most cases, the value of routine laparoscopy in chronic pelvic pain is very low. We propose that all women with chronic pelvic pain and normal pelvic examination should undergo psychological assessment and treatment if necessary. Laparoscopy should then be reserved for only those cases who show no amelioration on psychological intervention. Our estimation is that this approach would reduce the rate of laparoscopies performed for chronic pelvic pain by about 90%.

Adult↗
PubMed1985

Changes in bronchial hyperreactivity induced by 4 weeks of treatment with antiasthmatic drugs in patients with allergic asthma: a comparison between budesonide and terbutaline.

We performed a double-blind crossover study to compare the effects of long-term treatment of inhaled budesonide and terbutaline on bronchial hyperreactivity in 17 patients with allergic asthma. Both drugs were administered for 4 weeks with a placebo-treatment period before and after each active-treatment period. To assess bronchial hyperreactivity, standardized inhalation provocation tests with histamine and propranolol were performed every 2 weeks. Before each inhalation provocation the drugs were withheld for at least 12 hours. Before the budesonide treatment the FEV1 value (percent predicted) was 85.3 +/- 4.1% (mean +/- SEM). After 2 and 4 weeks of treatment with this drug, the value increased significantly to 89.4 +/- 4.1% and 96.2 +/- 3.8%, respectively (p less than 0.05 and p less than 0.005). The histamine provocation concentrations causing a decrease in FEV1 of 20% (PC20) on the same days were 4.0, 7.2, and 9.5 mg/ml, respectively (both p less than 0.001). The PC20 values for propranolol, which were measured 1 hour after the histamine provocation, were 11.7, 13.3, and 14.0 mg/ml (ns). The FEV1 values before and after 2 and 4 weeks of treatment with terbutaline were 86.2 +/- 4.0%, 84.8 +/- 4.1%, and 87.0 +/- 4.6%, respectively. The histamine PC20 values on the same days were 4.7, 3.1 (p less than 0.05), and 3.8 mg/ml, respectively. The propranolol PC20 values were 14.2, 8.7, and 10.1 mg/ml (p less than 0.001 and p less than 0.05, respectively. We conclude that budesonide improves bronchial hyperreactivity, possibly by a dampening of late allergic reactions, whereas treatment with terbutaline may lead to a temporary increase of bronchial hyperreactivity, possibly as a result of beta-receptor desensitization.

Adolescent↗
PubMed1985

Standardization of house dust mite extracts. Liberation of allergenic and antigenic components in relation to extraction conditions.

The spontaneous release of house dust mite components from cultures of Dermatophagoides pteronyssinus into slightly buffered water was studied against time, using both continuous and discontinuous extraction procedures. It was shown that proteins, carbohydrates, IgE binding components and precipitating antigenic components were rapidly released from the house dust mite cultures, reaching a maximal liberation within 1 h of extraction. Repeated extractions of house dust mite cultures (discontinuous extraction) showed an additional release of IgE components but the IgE binding potency declined after successive extractions, while showing increasing release of immunological inactive components. IgE binding to antigens immobilized to polystyrene surfaces (IgE-ELISA) appeared to be less sensitive compared with cyanogen-bromide activated discs (IgE-RAST). It was concluded that extraction procedures of house dust mite cultures with short incubation time of 1 h or less are to be preferred.

Allergens↗
PubMed1985

Volumetric aerobiological survey of conidial fungi in the North-East Netherlands. I. Seasonal patterns and the influence of metereological variables.

In order to obtain actual data about the qualitative and quantitative occurrence of airborne fungi in The Netherlands, a viable-volumetric sample survey with the Andersen sampler was undertaken. From April 1981 to the end of June 1983, one day a week samples were taken on the unobstructed rooftop of a hospital in the N-E Netherlands. An average of 268 Colony Forming Units (CFU), per sample, per cubic metre of air were found. Almost three-quarters of the total catch consisted of seven genera, Cladosporium predominating. Botrytis showed in surprisingly high numbers when compared with other surveys, while Alternaria occurred in very low concentrations. Most atmospheric airborne spora were found between May and September. Aspergillus and Penicillium prevailed in the autumn and winter months, although were present the year-round. Momentary weather conditions seemed less important for the overall spore picture than the average meteorological characteristics for a whole season. The obtained aero-mycological information may be useful in determining clinical strategies for skin testing and serological investigations in patients with suspected mould allergies.

Air Microbiology↗
PubMed1985

Volumetric aerobiological survey of conidial fungi in the North-East Netherlands. II. Comparison of aerobiological data and skin tests with mould extracts in an asthmatic population.

A study was undertaken to see whether the principal airborne fungi in the North-East Netherlands were also found to be the most reactive in skin testing. Atmospheric samples were taken weekly with the Andersen sampler, from April 1981, up to and including, June 1983. At the same time skin tests of 833 patients referred to the outpatient Departments of Pulmonology and Allergology, because of recurrent bronchial obstructive complaints and a suspected allergy, were studied for strongly positive skin reactivity to fungi. 4.6% of the patients reacted with a wheal of 10 mm diameter or more to one or more of the tested fungi. Almost three-quarters of the airborne fungal "flora" was composed of seven genera, namely (in order of occurrence): Cladosporium (42.6%), Botrytis (8.6%), Yeasts (7%), Penicillium (5.8%), Basidiomycetes (5.7%), Aspergillus (3.7%), and Alternaria (0.9%). In skin-testing, however, a different order of occurrence existed: namely: Beauveria (6.8%), Botrytis (6.1%), Aspergillus (4.7%), Mucor (3.8%), Epicoccum (3%), Cladosporium (2.3%), and Alternaria (1.1%). It is concluded that the most prevailing airborne moulds are not necessarily the most potent allergens, at least in skin testing. Aspergillus and Botrytis showed a high sensitization rate, while Cladosporium and Alternaria did not. Botrytis deserves further study because of its frequent airborne occurrence and marked allergenic properties.

Air Microbiology↗
PubMed1985

Cultivation of fungi in synthetic and semi-synthetic liquid medium. I. Growth characteristics of the fungi and biochemical properties of the isolated antigenic material.

Four allergologically important fungi, viz. Aspergillus fumigatus, Alternaria Penicillium notatum, and Cladosporium herbarum, were cultured in a pure synthetic medium and the patterns of growth as characterized by the pH, protein and carbohydrate concentration of the culture fluid, were studied. A fumigatus and P. notatum showed a similar growth pattern, characterized by a rapid decrease in the pH of the culture medium (pH 7.4----4.0), while proteins were slowly released and saccharose poorly consumed. In contrast, A. alternata and C. herbarum demonstrated a different pattern of growth, in which the pH of the culture hardly changed during incubation. Enrichment of the synthetic medium with yeast extract greatly improved the growth of all four fungi, as was confirmed by the enhanced yield of antigenic material and strongly increased consumption of saccharose. The yeast extract especially changed the growth pattern of A. fumigatus and P. notatum, which now is characterized by three phases. Phase I: fall in pH of the growth medium and excretion of proteins; phase II: increase in pH and fall in protein concentration; phase III: stabilization of pH at alkaline values and renewed excretions of proteins. It is concluded that during cultivation of the fungi, the metabolic state of the culture changes, influencing the antigenic composition of the extracts obtained after different periods of cultivation.

Antigens↗
PubMed1985

Cultivation of fungi in synthetic and semi-synthetic liquid medium. II. Immunochemical properties of the antigenic and allergenic extracts.

Four allergologically important fungi, viz. Aspergillus fumigatus, Penicillium notatum, Alternaria alternata, and Cladosporium herbarum were cultured in a liquid synthetic medium, with or without addition of 0.1% yeast extract (YE). After 10 and 28 days of cultivation, immunochemical properties of the fungal extracts, characterised by precipitation pattern and IgG- and IgE-binding capacity, were studied. In pure synthetic medium no large differences were observed in number of precipitates, as measured by DID, among the four antigenic fractions of each fungus (metabolic and mycelial antigens of both early and late phase cultures). Addition of YE to the growth medium hardly changed the number of precipitates and generally caused a decrease in IgG-binding capacity of the extracts. In contrast to these observations were the findings with the IgE-binding capacities of the fungal extracts as measured by RAST. Most allergenic fractions demonstrated an increase (sometimes strong) in IgE-binding capacity after YE was added to the growth medium. It is concluded that the time of cultivation influences the immunochemical characteristics of fungal extracts and that mycelial as well as metabolic antigens of both early and late phase cultures should be used in order to obtain a wide spectrum of allergens in extracts used for diagnostic purposes.

Allergens↗
PubMed1985

Reduced adenylate cyclase responsiveness to histamine in lymphocyte membranes of allergic asthmatic patients after allergen challenge.

The adenylate cyclase response to histamine was measured in lymphocyte membranes of allergic asthmatic patients and healthy control subjects, just before and 24 h after inhalation challenge with house dust mite allergen. In the non-acute phase before allergen challenge, the histamine response in the membranes of the patients was not significantly different from that in membranes of the control subjects. After the house dust mite-induced asthmatic reaction, however, the adenylate cyclase response to histamine in the membranes of the patients was significantly reduced by 47%, whereas allergen inhalation had no effect on the histamine response of the control membranes. The results suggest that allergic asthmatic reactions may cause reduced lymphocyte adenylate cyclase responsiveness to histamine. A similar mechanism in the airways might contribute to allergen-induced enhanced airway reactivity to histamine.

Adenylyl Cyclases↗
PubMed1985

Antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. I. Liberation of polystyrene binding components during cultivation.

The liberation of polystyrene binding antigenic components (PBC) of Aspergillus fumigatus involved in ELISA IgG measurements was studied during cultivation in the culture filtrates. PBC were rapidly liberated into the culture medium during the logarithmic phase of growth (phase I), were in part degraded or reconsumed during the stationary phase (phase II) and again secreted (other PBC) during the lytic phase (phase III). ELISA IgG titers and numbers of precipitating components are not always related with one another, may show an inverse relationship; maximal ELISA titers are reached during phase I when precipitating components are limited. The striking similarity between the liberation of PBC and IgE-binding components is discussed.

Antibodies, Fungal↗