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At least 343 records · Page 19Linked to original sources
PubMed1985

A mononuclear cell-derived histamine releasing factor in asthmatic patients. II. Activity in vivo.

In an attempt to study the role of lymphokines in asthma, lymphocytes from asthmatic patients were stimulated in vitro with skin test-positive allergen (dust mite) or with non-specific mitogen-phytohaemagglutinin for 4 h, then washed carefully and cultured alone for 16 h. Cell-free supernatants were subsequently collected and applied in the basophil histamine release test in vitro and in bronchial provocation test and skin prick test in vivo. Supernatant of non-stimulated lymphocytes from asthmatic patients released significant amounts of histamine from basophils. Stimulation of lymphocytes with specific allergen or phytohaemagglutinin augmented the supernatant-induced histamine release. Lymphocyte supernatants from the majority of patients also induced bronchoconstriction and elicited skin wheal and flare reaction in vivo.

Asthma↗
PubMed1997

Sensitization to Blomia kulagini in a general population of a subtropical region of Spain (Canary Islands).

The Blomia genus has been described as allergenic in man. The present study aimed to assess the prevalence of B. kulagini sensitization in a large population of allergic subjects without occupational exposure in a subtropical region (Canary Islands, Spain). Secondarily, a new standardized B. kulagini extract was evaluated. The study population comprised 207 patients. RAST for B. kulagini was positive in 76.2% of patients, and 47 of them were selected for the biologic standardization. When the prick test was performed with the nonstandardized extracts, results were positive in 76.6%, whereas when the test was repeated with the standardized extract, sensitivity rose to 95.7%. The conjunctival provocation test was positive in 78.3% of 46 evaluated patients. The bronchial provocation test was positive in 18 sensitized patients and negative in five controls. In conclusion, B. kulagini is an important cause of sensitization among the occupationally unexposed population of the studied area and should be included in allergy diagnostic tests. For reliable prick tests, the use of standardized extracts is mandatory.

Adolescent↗
PubMedDate not supplied

Bronchial responses to enalapril in asthmatic, hypertensive patients.

The subjects, six asthmatic patients with mild essential hypertension, were aged 48 to 63 years and each was being treated with theophylline. Five patients received 10 mg of enalapril daily for two weeks and one received 5 mg for four weeks. Their bronchial responses to inhaled methacholine were measured with a modification of the 3-Hz oscillation method before and after the enalapril treatment. The patients' mean blood pressures decreased significantly from 180.7/100.3 to 152.0/93.3 mmHg after treatment. No treatment-associated changes in the frequency of coughing, the number of asthmatic attacks, or use of antiasthmatic drugs were noted. The results of the bronchial provocation tests revealed no changes in bronchial sensitivity or reactivity during treatment. Serum substance P levels were 61.3 pg/ml before treatment and 60.2 pg/ml after treatment. It is concluded that therapeutic doses of enalapril did not exacerbate asthmatic attacks or increase bronchial hypersensitivity in these asthmatic, hypertensive patients.

Asthma↗
PubMed1988

[Persistence of nonspecific bronchial hyperreactivity in children with non-IgE dependent bronchial asthma: pharmacologic study with the Carbachol test].

The authors revise their preliminary experiment with the bronchial provocation test using carbachol in 50 children of 5 to 14 years with non-IgE dependent bronchial asthma who had been asymptomatic for one year prior to the test in order to make a clinical evaluation of asthma. The observe the evolution of the non-specific bronchial hyperreactivity (NSBH) with respect to the clinical remission and determine whether the persistence of NSBH is correlated to certain clinical, epidemiological and analytical parameters (peripheral eosinophilia, total IgE). In 22 children (44%) the functional respiratory examination was normal throughout each phase of the test. In the other 56%, the functional respiratory study using carbachol showed exhalation reductions which suggested NSBH. The most significant parameters were the reductions in FEV1, PEF (p less than 0.001) and FMEF (p = 0.001). Thus the patients revealing NSBH in the carbachol test are characterised for having revealed acute asthma of higher intensity, more often associated with an acute respiratory infection and with lower values of total IgE (p less than 0.05) with respect to the group without NSBH in the carbachol test.

Adolescent↗
PubMedDate not supplied

Bronchial provocation with cat allergen: long-term outcome of the late allergic reaction and the individual IgE CRIE pattern.

In bronchial provocation tests with allergen, about 50% of the patients experienced a late allergic reaction (LAR), which has been associated with a specific IgE pattern as determined by crossed radioimmunoelectrophoresis (CRIE). Long-term outcome of this LAR is still unknown. Six patients allergic to cat, with documented LAR and specific IgE CRIE patterns were rechallenged in the same conditions after a mean interval of 2.5 years. Forced expiratory volume in one second (FEV1) and resistance results of the bronchial provocation tests (BPT) were compared, as well as specific IgE level and IgE CRIE patterns. All six patients were still suffering from asthma when exposed to a cat, although they were not being treated for asthma. Three patients (50%) had lost their LAR without specific treatment. They were older, with a longer history of asthma, but presented a very similar early allergic reaction to similar allergen doses. The other 3 were more reactive to the allergen but presented similar LAR after a slightly worse early allergic reaction (EAR). Specific IgE levels had decreased and the IgE CRIE pattern showed a diminished intensity of staining in the three patients who had lost their LAR, as opposed to the other three. These data suggest that asthmatic patients can lose their LAR over time without treatment. The occurrence of a LAR seems to be associated with a specific IgE CRIE pattern and IgE level. Further analysis of the individual antigen fractions might help to understand the mechanism of allergic reactions.

Adult↗
PubMed2002

[A nationwide questionnaire survey on clinical application of pulmonary function testing in China].

OBJECTIVE: Assessment of the clinical application of pulmonary function testing (PFT) in China. METHOD: A questionnaire survey was performed in 212 hospitals covering 29 provinces of China. RESULTS: The response rate was 81.6%. PFT had been conducted in 91.9% of the responders, of which 69.2% were from large (provincial or municipal) hospitals. PFT was introduced to many hospitals in late 1970's, and has been used widely in early 1990's. Only 12.4% of the instruments being used was made domesticly. The frequencies of average PFT per month and per bed were low and a large variation existed among hospitals. PFT had been used more in the departments of internal medicine and surgery, but less in pediatrics, gynecology, and ENT. Spirometric measurement was the most common testing (performed 100%), followed by bronchial dilation test (74.2%) and bronchial provocation test (65.4%). Lung volume, diffusion capacity and airway resistance measurement had been conducted in 60.0%, 58.2%, and 42.7%, of the large hospitals, respectively. Exercise test was conducted in only 16.4% of the large hospitals. The reference norms were stated in only 21.4% of the hospitals. Prediction equations available for children were stated in only 16.9% hospitals where PFT were performed in children. Prediction equations derived from mainland Chinese were used in only 16.3% lung function laboratories. CONCLUSIONS: The clinical application of PFT in China is not popular and varies from hospital to hospital. It is imperative to develop domestic lung function instruments as well as lung function norms for Chinese.

China↗
PubMedDate not supplied

[Clinical and functional sequelae of bronchiolitis].

The authors carried out a follow-up on twenty-five children, affected with bronchiolitis in the early years of life, at seven years of age, in order to evaluate their clinical status and pulmonary function. Their parents were questioned about diseases of the small airways following to acute bronchiolitis. PRIST and RAST were effected in fourteen children; an evaluation of the pulmonary function with spirometry, flow-volume curve and body-plethysmography was done in every child. Then the flow-volume curve was repeated after bronchial provocation test with exercise (free running). Abnormalities of the pulmonary function at resting significant for small airways' obstruction were observed. A great number of children with bronchial hyperreactivity (60%) was observed after bronchial provocation test with exercise, particularly in those with genetic predisposition; 6/14 (43%) showed sensitization to many inhalant allergens, without correlation with genetic predisposition, clinical sequences and bronchial hyperreactivity.

Airway Resistance↗
PubMed1994

Histamine induced changes in breathing pattern may precede bronchoconstriction in selected patients with bronchial asthma.

BACKGROUND: In asthmatic patients methacholine or histamine challenge may result in more rapid and shallow breathing. Bronchoconstriction can also be associated with changes in the pattern of breathing. However, few studies, particularly in patients with asthma, have investigated the possibility that changes in the pattern of breathing may precede the onset of bronchoconstriction. METHODS: Eight subjects were selected from 34 consecutive asthmatic patients who had previously exhibited a significant increase in respiratory frequency (Rf) and decrease in tidal volume (VT) accompanying a 20% or greater fall in FEV1 during a histamine bronchial provocation test. These patients also had bronchial hyperresponsiveness (histamine PC20FEV1 0.1-0.25 mg/ml). VT, Rf, and the ratio of VT to Rf were evaluated breath by breath under control conditions and two minutes after inhalation of either saline or each of a series of progressively increasing concentrations of histamine. In each subject the coefficient of variation (CV) for each breathing pattern variable was calculated under control conditions and at each histamine concentration over at least 30-40 breaths. For FEV1, VT and Rf step by step coefficients of variation were averaged and the mean (2SD) CV was considered to represent a threshold value in each patient. RESULTS: Histamine challenge resulted in increased Rf and Rf/VT, and decreased VT and FEV1. In all but one subject change in Rf and Rf/VT beyond the threshold value preceded change in FEV1 beyond the threshold value. The threshold concentrations of histamine for Rf and Rf/VT did not correlate with the threshold value for FEV1. CONCLUSIONS: In selected asthmatic patients a change in breathing pattern occurs prior to a change in FEV1. These results suggest that narrowing of the airways, in terms of decrease in FEV1, does not play a major part in the initial change in the pattern of breathing. This may be caused by direct stimulation of vagal airway receptors.

Adult↗
PubMed1976

[Frequency and correlative relation of diagnostic criteria in animal dander allergy].

355 out-patients with signs of bronchial asthma were studied with special reference to animal dander sensitization. Case histories allowed the clinical diagnosis of an allergy to animal dander in 75 patients (21.1%). Skin testing is a useful means, as large reactions appear in most cases of animal dander allergy (60.7% are greater than or equal to + + + -reactions). Skin reactions, however, often are "false positive" or "false negative". Therefore, bronchial provocation tests are necessary if the case history is doubtful and/or the skin reaction is less than a + + + -reaction. There is a positive correlation between skin reaction and bronchial provocation test. No negative inhalation tests were seen when the skin reaction was greater than + + +. However, a positive inhalation test can be correlated with a negative or weakly positive skin test. The probability of common structural properties of different mammalian dander allergens is discussed. Avoidance of exposure to the animal is recommended as the therapy of choice.

Allergens↗
PubMed2001

Rhinoconjunctivitis and occupational asthma caused by Diplotaxis erucoides (wall rocket).

Wall rocket (Diplotaxis erucoides) is a common Crucifera plant that grows in European and American vineyards and olive groves. We present the cases of 2 farmers with rhinoconjunctivitis and asthma related to wine-growing tasks during D erucoides pollination (March-April). The aim of this work was to demonstrate that occupational symptoms were caused by D erucoides pollen sensitization. Cutaneous tests, specific IgE measurements, conjunctival and bronchial provocation tests, and peak-flow measurements during working days were performed.

Adult↗
PubMed1989

Airway refractoriness to adenosine 5'-monophosphate after repeated inhalation.

Adenosine-5'-monophosphate (AMP) is a bronchoconstrictor agonist in subjects with atopic and nonatopic asthma. In this study we have investigated the effect of repeated airway challenge with AMP in 10 atopic, subjects without asthma. At the first visit, subjects had repeated inhalation challenges with increasing doubling concentrations of AMP, and the provocation concentration required to reduce FEV1 by 20% of baseline was determined (PC20 AMP). When the FEV1 had returned to within 5% of the baseline, the AMP challenge test was repeated on a further one or two occasions. When the maximum concentration of AMP (400 mg/ml) failed to produce a PC20, a bronchial provocation test with histamine was performed and the PC20 was determined. On the second visit, the effect of three consecutive inhalation challenge tests with histamine on the airway response to this agonist was determined. On the third visit, the duration of induced refractoriness to AMP was assessed. With the first AMP challenge, all subjects demonstrated bronchoconstriction with a geometric mean (GM) PC20 of 332 mg/ml. With a second AMP challenge, five of the 10 subjects became refractory and failed to achieve a PC20. In the remaining five subjects, the GM PC20 increased from 110 to 583 mg/ml. With a third AMP challenge, these subjects also failed to achieve a PC20. The initial GM PC20 histamine for the group was 22.9 mg/ml, which did not change significantly with two further histamine challenges or when the airways were refractory to AMP, suggesting that loss of AMP effect was not related to loss of contractility of airway smooth muscle or down regulation of H1-histamine receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Monophosphate↗
PubMed1979

Protective antiallergic effects of a new coumarin compound (BM 15.100) in experimental asthma.

The antiallergic properties of a new coumarin compound (BM 15.100) were tested in two separate trials, using bronchial provocation tests in asymptomatic volunteers with extrinsic allergic bronchial asthma. Study I was a blind study in 10 subjects with placebo controls and three additional non-medicated controls. Study II was an open study with non-medicated controls. Body plethysmography (study I) and spirometry (study II) were used for the assessment of bronchial obstruction. A significant protective effect of a single oral 20 mg dose of BM 15.100 administered 60 min prior to allergen inhalation was found in both trials. The effect of 10 mg BM 15.000 was not significant. Skin test, pulse rate, and diastolic blood pressure were not influenced. The results indicate a possible therapeutical value of BM 15.100.

Airway Resistance↗
PubMed1985

Occupational allergy to sunflower pollen.

Although the sunflower belongs to the Compositeae family, allergy to sunflower pollen is not common. The occurrence of occupational allergy to this pollen species made it possible to characterize cross-reactive patterns of Compositeae pollens in a human experimental model. A 24-yr-old man developed rhinitis and conjunctivitis over 5 yr of exposure to sunflower pollens, and asthma developed during the fifth year. All respiratory and occular symptoms disappeared after he was removed from exposure, but he had a food allergic reaction while he was eating honey containing 30% sunflower pollens. The diagnosis of occupational allergy was based on history, skin prick tests and RAST to the pollen. Bronchial provocation tests performed after removal from exposure confirmed the sensitivity to sunflower pollens but there was no nonspecific hyperreactivity. It was found by RAST inhibition that sunflower pollen does not cross-react with other Compositeae pollens tested or with sunflower seed. The honey that elicited food intolerance was demonstrated to inhibit significantly sunflower pollen RAST.

Adult↗
PubMed1979

Peak flow rate records in the diagnosis of occupational asthma due to isocyanates.

Peak expiratory flow rate (PEFR) has been recorded hourly or two-hourly from waking to sleeping in workers with respiratory symptoms who were exposed to isocyanate fumes at work. Twenty-three recordings averaging 33 days duration were recorded in 20 workers. Each worker was also admitted for bronchial provocation testing to toluene di-isocyanate (TDI) or diphenylmethane di-isocyanate (MDI) fumes or both. A final assessment of work-related asthma made from subsequent work exposure was compared with the results of bronchial provocation testing and a subjective assessment of the peak flow records. Both techniques were specific and sensitive. Physiological patterns of occupational asthma were defined from the records of PEFR. The most striking finding was the slow recovery from work-induced asthma. This commonly took several days to start and in one worker took 70 days to complete after leaving work. Several workers developed a pattern resembling fixed airways obstruction after repeated exposure at work. The consequences of these findings for the recording of symptoms of occupational asthma are discussed and recommendations are made for the recording of PEFR in workers in general.

Asthma↗