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K De Vries

Publications and source records attributed to K De Vries.

17 recordsLinked to original sources
PubMed1993

Factors associated with bronchial responsiveness to histamine in a population sample of adults.

The association of age, gender, number of eosinophils, area of residence, cigarette smoking, respiratory symptom prevalence, and FEV1 with the level of bronchial responsiveness was studied in a random sample of 2,216 subjects aged 15 to 72 yr. Subjects participated in the Dutch longitudinal study on chronic obstructive pulmonary disease. In 18 yr of follow-up, 5,012 observations were collected. Interviewers used a standardized questionnaire to assess the presence of respiratory symptoms. Bronchial responsiveness was measured by a histamine challenge test. Because multiple measurements within a subject are correlated, multivariate regression methods for correlated outcome were used. A greater number of eosinophils, skin test positivity, and living in a rural area (Vlagtwedde) were associated with increased responsiveness, independently of the level of FEV1 and the presence of respiratory symptoms. Older age was associated with increased responsiveness, and this was even more so in subjects with symptoms. Cigarette smokers were more responsive than nonsmokers, but this association was not significant if the level of FEV1 was taken into account. Hyperresponsiveness was more likely to be present if the amount of cigarettes smoked per day was greater. The level of responsiveness did not differ significantly between males and females. For the same degree of obstruction, however, expressed as the FEV1/VC ratio, males tended to be less responsive than females. The analyses were repeated using the dose-response slope as a continuous measure of responsiveness and by applying a method to adjust for censoring the responsiveness data. These analyses yielded identical results.

Adult↗
PubMed1993

Long-term variability of bronchial responsiveness to histamine in a random population sample of adults.

Long-term variability of bronchial responsiveness has been studied in a random population sample of adults. During a follow-up period of 18 yr, 2,216 subjects contributed 5,012 observations to the analyses. Each subject could have as many as seven observations. Bronchial responsiveness was assessed with a histamine challenge test. The threshold value was defined as the concentration of histamine that caused a decrease in FEV1 of 10% of more (PC10). After a 3-yr interval, a change of the threshold value with two or more doubling concentrations occurred in 21% of the subjects. This proportion increased to 43% if the time between two measurements increased to 18 yr. Of all subjects with multiple observations, 41% were always nonresponders (PC10 > or = 32 mg/ml), 11% were always responders (PC10 < or = 16 mg/ml), and 48% changed responder status. Of the subjects with greater than three observations, 65% changed responder status. Regression analyses, stratified by symptom status, sex, and smoking habit, were used to estimate intraclass correlation coefficients (ICC) as a measure of variability of responsiveness. On average, ICC values were low (0.40), also indicating considerable variability. With adjustment for FEV1, age, area of residence, and eosinophil count, the ICC values decreased slightly. This indicated that with adjustment, the total variability decreased more than the within-subject variability. ICC values did not differ significantly between asymptomatic and symptomatic subjects. Analyses of responsiveness as a binary variable revealed similar results.

Adolescent↗
PubMed1991

Dissimilarity in methacholine and adenosine 5'-monophosphate responsiveness 3 and 24 h after allergen challenge.

Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5'-monophosphate (AMP) was studied in 15 allergic asthmatic patients before and 3 and 24 h after allergen challenge with house dust mite (HDM). Subjects attended the clinic on 3 consecutive days. On the first day a control solution was inhaled, and methacholine or AMP challenge was performed 3 h later. The next day HDM was inhaled, and 3 and 24 h later methacholine or AMP challenge was performed again. There were no significant difference in FEV1 baseline value between any of the study days. PD20 HDM, percentage decrease in FEV1, and AUC for both the EAR and LAR were not significantly different in the methacholine and AMP studies. After HDM challenge, PC20 methacholine decreased significantly from a geometric mean (+/- SEM) starting value of 1.39 +/- 0.63 mg/ml to 0.30 +/- 0.78 mg/ml (p less than 0.001) at 3 h and to 0.22 +/- 0.75 mg/ml (p less than 0.001) at 24 h. The magnitude of the decrease in PC20 methacholine at 3 h correlated with the severity of the late asthmatic reaction (LAR) as measured by the percentage fall in FEV1 and area under the curve (AUC) (r = -0.60 and r = 0.55; p less than 0.05). A significant decrease was observed in the PC20 AMP at 3 h, from a geometric mean value of 12.2 +/- 0.96 mg/ml after challenge with the control solution to 4.47 +/- 0.99 mg/ml (p less than 0.05) after HDM challenge.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Monophosphate↗
PubMed1988

Dosage and time effects of inhaled budesonide on bronchial hyperreactivity.

In a double-blind study of 2 parallel groups of 15 allergic asthmatic patients each, we investigated whether treatment with inhaled budesonide has a dose- and time-dependent effect on the degree of bronchial hyperreactivity. The patients were randomly allocated to treatment with either 200 or 800 micrograms budesonide per day for a period of 8 wk. The active treatment period was preceded by a selection period of 3 wk, and a single-blind placebo period of 2 wk. During these initial 5 wk the maintenance treatment of the patients, including cromolyn sodium and inhaled corticosteroids, was withheld. Spirometry and inhalation provocation tests with methacholine were carried out, and the symptom score was recorded every 2 wk. The methacholine provocation concentrations (geometric mean) causing a decrease in FEV1 of 20% (PC20) in the 200 and 800 micrograms/day treatment groups just before the active treatment period were 0.90 and 0.91 mg/ml, respectively. These values increased significantly to 1.21 and 1.84 mg/ml after 2 wk of treatment (p less than 0.05 and p less than 0.001, respectively) and to 1.55 and 2.74 mg/ml after 8 wk of treatment (p less than 0.01 and p less than 0.001). During the whole study period budesonide in a dosage of 800 micrograms/day induced a significantly larger change in PC20 than in a dosage of 200 micrograms/day. The FEV1 before treatment was 91 +/- 3% (SEM) and 84 +/- 2% of the predicted value in the 200 and 800 micrograms/day treatment groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗
PubMed1985

Influence of the parasympathetic and sympathetic nervous system on nocturnal bronchial obstruction.

To determine whether an autonomic nervous system imbalance might underlie the nocturnal dyspnoea in patients with chronic airflow obstruction (CAO), we determined FEV1, sinus arrhythmia gap (SA gap), heart rate and urinary adrenaline and noradrenaline excretion every 4 h over 24 h. Measurements were performed in eight non-allergic patients with CAO and eight age- and sex-matched normal controls. The amplitude of the circadian changes in FEV1 in patients and controls was 27 +/- 2% and 7 +/- 1% respectively (P less than 0.001). Both an increased SA gap and a decreased heart rate are features of increased vagal activity. This vagal activity was significantly increased in patients, compared with normal controls (difference P less than 0.01), the difference being maximal at night. This increased activity might contribute to a bronchial obstruction in these patients. Urinary adrenaline excretion was significantly higher by day than by night in both patients and normal controls (P less than 0.01). The urinary levels of adrenaline in the patients were significantly decreased at all hours of observation as compared with levels in normal controls (P less than 0.05). Urinary noradrenaline levels were significantly lower in patients as compared with normal subjects (P less than 0.01), and lower by night than by day. Urinary histamine and Nt-methylhistamine excretion were in the normal range in each individual. Urinary levels, however, were significantly higher in patients at all hours of observation (P less than 0.05). No circadian rhythm was shown. Plasma cortisol levels showed a normal circadian variation, similar in patients and normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Effect of beta-adrenergic stimulation on the circulatory lymphocyte count: studies in normals and in patients with chronic airflow obstruction.

In eight non-allergic patients with chronic airflow obstruction (CAO) and eight age and sex matched, healthy control subjects the circadian variation in circulatory lymphocyte count was studied in relation to serum cortisol and urinary epinephrine levels. In addition, we investigated the effect of the beta-adrenergic agent terbutaline on the lymphocyte count in two ways: as a long-term effect after 8 days of oral slow-release terbutaline with constant diurnal and nocturnal serum levels in patients, and as a short-term effect by a constant rate infusion of 0.2 micrograms/min over 4 hr in normals. Both patients and controls showed similar circadian patterns of urinary epinephrine excretion and lymphocyte counts. Patients with CAO, however, had significantly lower epinephrine levels and significantly higher lymphocyte counts at all hours of observation (every 4 hr from 0800 to 0800 hr the next day), as compared with normal controls. After 8 days of slow-release terbutaline the lymphocyte count in the patient group decreased to levels not significantly different from that of normals. The circadian rhythm of the lymphocytes, however, persisted under terbutaline therapy. No correlation existed between the lymphocyte count modulating factor, serum cortisol and the lymphocyte count over 24 hr. On placebo infusion in the control persons an increase of lymphocytes over 4 hr occurred, as a consequence of circadian rhythmicity. On terbutaline infusion a significant increase of lymphocytes after 1 hr was followed by a decrease to levels significantly below those on the placebo day. The same pattern was found in the leucocyte count. From this study it is concluded that beta-adrenergic stimulation corrects the relative lymphocytosis to counts comparable with normals. Other coinciding factors must regulate, however, the circadian rhythmicity.

Adult↗
PubMed1985

Bronchoalveolar eosinophilia during allergen-induced late asthmatic reactions.

In order to obtain information about the nature of the local inflammatory process during late asthmatic reactions after house dust mite inhalation, bronchoalveolar lavage (BAL) was performed in 19 asthmatic patients and in 5 control subjects. In 16 of the patients and in all of the control subjects, BAL was performed 6 to 7 h after allergen inhalation. Six of the patients showed early and late asthmatic reactions (LAR), 5 showed early reactions, and 5 showed no reactions. Bronchoalveolar lavage was also performed shortly after the early reaction in 5 patients with documented combined early and late reactions. In the BAL fluid of the patients with LAR, a significant eosinophilia (0.01 less than p less than 0.05) was found compared with that in all other patient groups and with that in the control subjects. This bronchoalveolar eosinophilia was accompanied by elevated eosinophil cationic protein/albumin ratio in the BAL fluid (0.01 less than p less than 0.05). These observations suggest that eosinophils and their mediators might be involved in the development of LAR after allergen inhalation.

Adult↗
PubMed1985

Sequential sampling of fungal air spores inside and outside the homes of mould-sensitive, asthmatic patients: a search for a relationship to obstructive reactions.

A sequential sampling study of fungal airspores was carried out with the Andersen sampler inside and outside the homes of eight asthmatic, mould-sensitive patients. The aim of the study was to find a possible relationship between variations in airborne colony forming units (CFU) and the occurrence of increased pulmonary complaints (IPC). Great variations in fungal prevalence occurred throughout the year, the lowest average daily concentration being 125, and the highest, 1425 CFU/m3/sample during the whole survey. Penicillium dominated the catch in seven of the eight environments. Other frequently sampled moulds were Cladosporium, yeasts, Aspergillus, and Botrytis. Sixty-six percent of IPC were noted from July through November, during which time 56% of all fungal peaks occurred. A significant difference was found between peak flow (PF) values on days with the highest mould numbers compared with PF values on days with low counts. This relation was not found for PF and indoor mould counts. No particular fungal genus was responsible for IPC in general, but in a given patient the occurrence of a special mould type may be related to obstructive reactions. It is concluded that a possible relationship exists between the prevalence of airborne fungi and IPC. Definite proof of a direct bronchial obstructive effect, however, might only be provided by means of inhalation-provocation studies with the sampled fungi.

Air Pollutants↗
PubMed1983

A single centrifugation step method for the simultaneous separation of different leukocytes with special reference to basophilic leukocytes.

A simple method of separating mononuclear leukocytes, basophils, neutrophils and an eosinophil fraction from human blood is described, using discontinuous Percoll gradient centrifugation. Mononuclear cells were found in the upper layer (band 1) at a density of less than or equal to 1.072. The second band with a density of less than or equal to 1.082 contained most of the basophilic leukocytes (av. 70% and 8-20% of the differential cell count) and a minor part of the mononuclear cells (av. 8%). In the third band, density less than or equal to 1.1, 82-91% of the polymorphonuclear cells (PMN) were found, consisting mainly of neutrophils. 35-70% of the eosinophilic PMN cells are located in band four (density greater than 1.1). The function of the basophil-enriched fraction was tested by degranulation with specific antigen.

Basophils↗
PubMedDate not supplied

Emergency versus elective microsurgery.

During a 30-months period, a total of 148 microsurgical gynecological operations were performed in our department. We divided these operations into two groups: Emergency microsurgical operations, where microsurgical technique is used in urgent cases for preservation of fertility potential, and elective microsurgical operations, performed for restoration of fertility. We compared the two groups with regard to their inherent characteristics and differences in therapeutic and prognostic approach towards them. The results of our comparison show, that these two groups having in common only the microsurgical approach, are different from each other in the following points: The average age of the emergency microsurgery group was younger since it contained also prefertility cases; the timing of operations in the elective group was always in the proliferative phase of the menstrual cycle; antibiotics were given pre-, intra and postoperatively only in the elective group; corticosteroids were given intra- and postoperatively only in the elective group; the average number of different operative procedures performed during one operation was higher in the restorative group; desire for pregnancy was always present in the restorative and inconstantly in the preservative group; results of the operations regarding intrauterine pregnancy can be evaluated only for the elective, and not for the emergency group. Psychological evaluation of cases can be performed in the elective and not in the emergency group. Because of these differences, a division of microsurgical operations into elective and emergency microsurgery seems justified and valuable to us.

Adolescent↗