PubMed Health⌕ Search

Biomedical subjects

D Barber

Publications and source records attributed to D Barber.

At least 37 records · Page 2Linked to original sources
PubMed1993

In vivo allergenic activities of eleven purified members of a major allergen family from wheat and barley flour.

Eleven purified members of the alpha-amylase/trypsin inhibitor family from wheat and barley that showed very different IgE-binding capacities when previously assayed in vitro, were used in double blind in vivo diagnostic tests to further evaluate their allergenic activity. These tests were carried out in 31 patients who showed allergic sensitization to wheat flour as verified by skin test, RAST and challenge test. The three members of the protein family with highest IgE binding in vitro (the glycosylated subunits of tetrameric alpha-amylase inhibitors CM16* from wheat and CMb* from barley, and the barley monomeric inhibitor BMAI-1) were found to be the strongest allergens as indicated by skin sensitivity in prick tests.

Adolescent↗
PubMed1992

Endobronchial hamartoma. A case report.

A patient with a very rare benign bronchial tumour who presented in a most unusual manner is described. An endobrachial hamartoma was expectorated 24 hours after bronchoscopic manipulation for a suspected malignant tumour.

Bronchial Neoplasms↗
PubMed1992

Chromosome size-dependent control of meiotic recombination.

Smaller chromosomes have higher rates of meiotic reciprocal recombination (centimorgans per kilobase pair) than larger chromosomes. This report demonstrates that decreasing the size of Saccharomyces cerevisiae chromosomal DNA molecules increases rates of meiotic recombination and increasing chromosome size decreases recombination rates. These results indicate that chromosome size directly affects meiotic reciprocal recombination.

Chromosome Mapping↗
PubMed1992

Wheat and barley allergens associated with baker's asthma. Glycosylated subunits of the alpha-amylase-inhibitor family have enhanced IgE-binding capacity.

A 16 kDa protein, designated CM16*, which strongly binds IgE from baker's-asthma patients has been identified as a glycosylated form of the previously reported WTAI-CM16, which is a subunit of the wheat tetrameric alpha-amylase inhibitor. A glycosylated form (CMb*) of BTAI-CMb, the equivalent inhibitor subunit from barley, has been also found to have significantly enhanced IgE-binding capacity. In all, 14 purified members of the alpha-amylase/trypsin-inhibitor family showed very different IgE-binding capacities when tested by a dot-blot assay. The glycosylated components CM16*, CMb* and the previously described non-glycosylated 14.5 kDa allergen from barley (renamed BMAI-1) were found to be the strongest allergens.

Allergens↗
PubMed1992

Monoclonal antibodies against Olea europaea major allergen: allergenic activity of affinity-purified allergen and depleted extract and development of a radioimmunoassay for the quantitation of the allergen.

Several monoclonal antibodies (MAbs) were raised against Olea europaea pollen-extract components. Two of these antibodies, named OL 2 and OL 7, recognize two nonoverlapping, nonrepeating epitopes on the olive-allergen Ole e I, as demonstrated by different techniques. The allergen was purified in a single step by MAb-based affinity chromatography, and the allergen revealed a band at molecular weight 20 kd as well as a minor band at 18 kd on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The contribution of allergen Ole e I to the allergenic activity of O. europaea pollen extracts was determined from the effect of allergen depletion by affinity chromatography on skin reactivity and a histamine-release test. The removal of allergen caused a large reduction in the activity of the preparation in 25 monospecific olive-allergic patients. In agreement, the affinity-purified allergen demonstrated a similar response when it was compared with the whole extract in these assays. The results indicated that Ole e I is by far the most important olive-pollen allergen. A two-site solid-phase radioimmunoassay was developed for the quantitation of the allergen Ole e I in mass units. The assay was based on the MAbs, OL 2 and OL 7, and had a detection limit in the nanogram range. A good correlation was found between allergenic activity, as determined by RAST inhibition, and allergen content in 18 olive-pollen extracts. This result indicates that the assay can be a good alternative to RAST inhibition for the standardization of O. europaea extracts.

Allergens↗
PubMed1992

Evaluation of immune complexes after immunotherapy with wheat flour in bakers' asthma.

Inhalant food allergy has been described many times in literature, but double-blind clinical trials to support successful hyposensitization to these allergens has seldom been reported. Some authors have suspected that certain adverse reactions after immunotherapy may be mediated by immune complexes. Furthermore, the FDA does not recommend injection therapy with food extracts. We present a study on the detection of adverse effects after immunotherapy with an inhalant food (wheat flour) in a double-blind clinical trial in 26 patients with bakers' asthma. We investigated the presence of circulating immune complexes (CICs) after 2 years of treatment with hyposensitization to wheat flour.

Antigen-Antibody Complex↗
PubMed1992

Sensitization to the storage mite Lepidoglyphus destructor in wheat flour respiratory allergy.

Occupational allergy due to hypersensitivity to cereal flours is relatively common among bakers and grain-store workers. Storage mites can contaminate wheat flour and could be an important cause of allergic symptoms due to inhalation. Forty-three patients with criteria for allergic sensitization to wheat flour (skin tests, specific IgE to wheat flour and positive challenge tests) were included in a study to investigate the prevalence of cosensitization to Lepidoglyphus destructor (Ld). This mite was the predominant species in the wheat flour samples supplied by our patients. We found that 30% of the patients had IgE-mediated hypersensitivity of Ld. Of these, 23% did not have a relationship with any bakery or agriculture. We conclude that the prevalence of sensitization to Ld in patients sensitized to wheat flour is important.

Adolescent↗
PubMed1990

Members of the alpha-amylase inhibitors family from wheat endosperm are major allergens associated with baker's asthma.

We have identified the major antigens or IgE binding components from wheat flour. Thirty-five sera from patients with baker's asthma were used to analyze the reaction with wheat salt-soluble proteins. We found a 15 kDa SDS-PAGE band which reacted with all sera tested. Purified members of the alpha-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after two-dimensional electrophoretic fractionation of crude inhibitor preparations from wheat endosperms also detected several inhibitor subunits as major low-molecular-weight allergens.

Allergens↗
PubMed1990

Bakers' asthma: prevalence and evaluation of immunotherapy with a wheat flour extract.

One hundred thirty-nine bakers and pastry cooks were included in a prevalence study of IgE-mediated hypersensitivity to wheat flour demonstrated by skin tests, specific IgE to wheat flour (RAST), and inhalation challenge. From the sensitized workers, we selected 30 asthmatic patients. Twenty patients were treated with a standardized wheat flour extract, and ten with a placebo in a double-blind clinical trial. Before and after immunotherapy we performed tests in vivo (skin tests with wheat flour and methacholine tests), and in vitro (total IgE and specific IgE to wheat flour). We found substantial prevalence of wheat flour allergy (25.17% of workers), and a significant decrease (P less than .001) in hyperresponsiveness to methacholine, skin sensitivity (P = .002), and specific IgE (P less than .005) to wheat flour after 20 months of immunotherapy. There was also significant subjective improvement (P less than .001). The placebo group showed no changes in these variables.

Adolescent↗
PubMed1990

Allergenic variability in olea pollen.

Marked in vitro allergenic potency variations were observed among six different olive pollen batches as determined by RAST inhibition, in direct correlation with the content of a multimeric component of 55,000 D as analyzed by size-exclusion high performance liquid chromotography. Electrophoretical patterns displayed differences in a heterogeneous band of 20,000 D and isoelectric point around 5, which probably represents the monomeric form of the major allergen.

Allergens↗
PubMed1990

Exercise-induced anaphylactic reaction to grain flours.

On rare occasions, reproducible exercise-induced anaphylactic reactions (EIA) occur in some patients only after certain foods have been eaten before exercise, yet eating these foods alone or exercising alone causes no symptoms. This special response has been evident sometimes with shellfish, nuts, and wheat. We describe a patient in whom grain flour was a triggering factor for EIA. Skin tests and RAST were positive for grain flours. Normally, the patient tolerated grain flours without symptoms and IgE mechanisms had not been suspected. Testing for food hypersensitivity may be important in patients with EIA.

Anaphylaxis↗
PubMed1986

New alpha-amylase and trypsin inhibitors among the CM-proteins of barley (Hordeum vulgare).

Barley CM-proteins are a group of at least five salt-soluble components (CMa-e) that can be selectively extracted from endosperm with chloroform/methanol mixtures. N-terminal sequences of proteins CMa, CMb and CMc have been determined and found to be homologous to those previously determined for CMd and CMe, an observation which confirms that their structural genes are members of a dispersed multi-gene family. The purified CM-proteins were tested against trypsin and against alpha-amylases from saliva, pancreas, Aspergillus oryzae, Tenebrio molitor and barley. Besides CMe, which was known to be a trypsin inhibitor, CMc also showed antitrypsin activity, whereas CMa was specifically active against the alpha-amylase from T. molitor and no inhibitory activity was found for proteins CMb and CMd. The evolutionary implications of these findings are discussed.

Amino Acid Sequence↗