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F Beaumont

Publications and source records attributed to F Beaumont.

At least 19 recordsLinked to original sources
PubMed2001

[Persistent infiltrative pulmonary disease].

Two patients, a woman aged 63 and a man aged 64 years, were admitted with pulmonary complaints and persistent infiltrative lung abnormalities as revealed in chest X-rays. Routine diagnostic analysis did not lead to a diagnosis. However, a pathological examination of biopsies acquired by means of video-assisted thoracoscopic surgery (VATS), revealed bronchiolitis obliterans organising pneumonia (BOOP). In the first patient the BOOP manifested itself as a rapidly progressive disease with fever, pulmonary complaints and X-ray abnormalities. There was no response to standard antibiotic treatment. The other patient had suffered from rheumatoid arthritis for a considerable time and gradually developed BOOP. Both patients recovered following adequate therapy with high doses of oral corticosteroids. BOOP is a pathological-anatomical entity. It is a nonspecific excessive repair response to a variety of stimuli, such as infection, drugs, collagen vascular diseases, inflammatory disorders, transplantation, intoxication and irradiation. BOOP can also occur idiopathically. A high-resolution CT-scan is useful in distinguishing BOOP from interstitial pulmonary fibrosis and other interstitial lung diseases. An open lung biopsy is necessary for the diagnosis BOOP and is best performed by means of VATS. The treatment of BOOP consists of administering high doses of corticosteroids (prednisone 1 mg/kg/day) and if treated adequately, the prognosis is fairly good. Due to the extensive variety in aetiology, the specific diagnostic procedures and the good response to necessary treatment, BOOP should be considered in the differential diagnosis of patients with persistent infiltrative lung disease.

Acute Disease↗
PubMed1996

Specific IgG4 responses during chronic and transient antigen exposure in aspergillosis.

The factors that lead to increased production of specific IgG subclasses are still largely unknown. Recent studies suggest that increased IgG4 responses may be related to prolonged antigen exposure. We present data showing that increased IgG4 responses are found under conditions of chronic exposure to Aspergillus fumigatus (Af) antigen. IgG(total), IgG subclass, and IgE responses were studied using ELISA, CAP-FEIA, and immunoblotting techniques in patients with pulmonary aspergilloma (PA), which is a model for chronic antigen exposure, and allergic bronchopulmonary aspergillosis (ABPA), characterized by transient antigen exposure. Af-IgG1 was increased in patients with PA compared with those with ABPA. Patients with PA and IgE responses to Af and/or other inhalant allergens showed significantly higher Af-IgG4 responses than did patients with PA and negative IgE responses or patients with ABPA. Surveillance studies over time in individual patients showed concordance in Af-IgG1 and Af-IgG4 responses. Both Af-IgG1 and Af-IgG4 levels followed the course of disease progression and treatment. Immunoblotting revealed correlations between Af-IgG1 and Af-IgG4 binding to most, but not all, antigenic Af components. This study documents for the first time increased IgG4 levels under conditions of chronic exposure to fungal antigen in PA. Furthermore, a significantly higher IgG4 response was found in those patients with PA who produced IgE. The transient exposure to Af antigen during exacerbation of ABPA gives rise to transient elevations in IgG4 levels.

Antigens, Fungal↗
PubMed1987

Expression of class II major histocompatibility complex antigens on alveolar epithelium in interstitial lung disease: relevance to pathogenesis of idiopathic pulmonary fibrosis.

To determine whether expression of class II major histocompatibility complex antigens on alveolar epithelium is relevant to the pathogenesis of idiopathic pulmonary fibrosis (IPF) lung biopsy specimens were investigated from nine patients with IPF with or without connective tissue disease, four patients with sarcoidosis, eight patients with lung disease of presumably infectious origin, and five controls. The alveolar epithelium stained strongly with anti-Ia (HLA-DR) or Leu 10 (HLA-DS) monoclonal antibodies, in eight of nine biopsy specimens from patients with IPF, in three of four biopsy specimens from patients with sarcoidosis, in all six biopsy specimens from patients with presumably viral, mycobacterial, or pneumocystic lung disease, but not in control lung tissue, nor in two biopsy specimens from patients with bacterial pneumonia. Mononuclear cell infiltrates consisted of T4 positive (helper/inducer) lymphocytes, predominantly present in a nodular arrangement in the interstitium, and T8 positive (cytotoxic/suppressor) cells, distributed equally in the interstitium and subepithelially or intraepithelially. T8 cells outnumbered T4 cells in six of nine biopsy specimens from patients with IPF, but in none of the biopsy specimens from patients with sarcoidosis or interstitial lung disease of infectious origin. Although the expression of class II antigens on the alveolar epithelium which is infiltrated by T8 cells in IPF is consistent with local presentation of autoantigens and an ensuing local immune response, class II expression is also present in interstitial lung disease of sarcoidosis and microbial infections: its role in the pathogenesis of IPF must therefore remain speculative.

Adolescent↗
PubMed1987

Expression of class II MHC antigens on alveolar epithelium in fibrosing alveolitis.

Lung biopsy specimens from eight patients with fibrosing alveolitis with or without connective tissue disease were investigated for the presence of immune deposits and the expression of class II histocompatibility antigens on the alveolar epithelium. Immune deposits were not detected. The alveolar epithelium stained strongly with anti-Ia (HLA-DR) monoclonal antibodies in seven out of eight biopsy specimens from the patients, but not in control lung tissue. Sub- and intra-epithelially localized mononuclear cell infiltrates consisted predominantly of T8-positive (cytotoxic/suppressor) lymphocytes. The expression of class II antigens on the alveolar epithelium and its infiltration with T8 positive cells is consistent with local presentation of self-antigens and an ensuing local immune response.

Adult↗
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↗
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

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

Antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. II. Physico- and immunochemical properties of the polystyrene-binding components.

Polystyrene-binding antigenic components (PBC) of Aspergillus fumigatus involved in ELISA IgG antibody determinations and the corresponding numbers of precipitates found by double immunodiffusion (DID) and/or crossed immunoelectrophoresis (CIE) were studied using culture filtrate antigenic preparations fractionated by Sephadex G-100 chromatography, concanavalin A (ConA) affinity chromatography, isoelectric focusing (IEF) and TCA precipitation. It is shown that PBC, immunologically active in ELISA, are characterized by high molecular weights and ConA-binding properties. The pI values of these components were 3.5-6 and above 8. The glycoprotein and/or mucopolysaccharide nature is suggested by the binding to ConA and their partial resistance to trichloroacetic acid treatment. By contrast, low-molecular weight components and antigenic components that are not absorbed by ConA being active in DID and/or CIE showed less or absence of binding to the polystyrene surface.

Antibodies, Fungal↗
PubMed1985

Standardization of allergenic extracts of Aspergillus fumigatus. Liberation of IgE-binding components during cultivation.

During cultivation of Aspergillus fumigatus a rapid liberation of IgE-binding components was found reaching maximum values during the logarithmic phase of growth (phase I). After a fall in IgE-binding titers during phase II, appearance of additional IgE-binding components was noted during the period of lysis of the microorganism (phase III). These latter allergenic components are different from the phase I IgE-binding components, as was shown by crossed-inhibition studies. The number of precipitating antigenic components was not related with the corresponding IgE-binding titers and showed an increase during all phases of growth. The rapid changes in both IgE- and IgG-binding properties and the discrepancies between precipitating properties and IgE binding are discussed in relation to standardization and quality control of aspergillus extracts.

Allergens↗
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↗