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Biomedical subjects

D R Ownby

Publications and source records attributed to D R Ownby.

At least 37 records · Page 2Linked to original sources
PubMed1996

Incidence and prevalence of physician-diagnosed asthma in a suburban population of young adults.

BACKGROUND: Asthma is a common chronic disease of both children and adults, but there have been few reports of the incidence of asthma in well defined adult populations. OBJECTIVE: To determine the incidence and prevalence of asthma in a population of young adults living in suburban Detroit. METHODS: As part of a study of the development of allergic disease in children, the parents of 841 study children, from a defined, well characterized population, were questioned about their personal histories of allergic disease, including asthma, during the mother's pregnancy. The children have been followed from birth until 4 years of age. When the child became 4, the parents were again questioned about allergic disease. Those reporting asthma when the child was 4 but not prior to the child's birth, were recontacted to confirm that they had been diagnosed by a physician as having asthma in the 4-year interval. Because of prior reports concerning racial differences in the prevalence of asthma and the small number of non-white mothers in the study population, calculations of asthma prevalence and incidence were limited to the 760 mothers, who described themselves and their baby's father as white. RESULTS: The parents studied were young adults mean age 28.7 [(standard deviation (SD) 4.5 years] and 31.0 (SD 5.0) years, of mothers and fathers, respectively. These parents were relatively well educated with 30.7% of mothers and 43.5% of fathers having college degrees. The initial prevalence of a previous physician diagnosis of asthma was 7.5% [95% confidence interval (95% CI) = 5.7-9.6] in the mothers and 6.9% (95% CI = 5.2-9.0) in the fathers, yielding a total prevalence of 7.2% (95% CI = 5.9-8.7) in these 1484 adults. Five hundred thirty-three mothers and 498 fathers (total = 1031), who did not report asthma during the mothers' pregnancies, were available for questioning when the children were 4 years old. The average yearly incidence of asthma was 5.2 (95% CI = 2.6-9.2) per 1000 in the mothers and 1.5 (95% CI = 0.3-4.4) per 1000 in the fathers (P = .058), with an overall incidence of 3.4 (95% CI = 1.8-5.7) per 1000. The average yearly incidence was 5.3/1000 in those < 30 years old and 1.5/1000 in those > or = 30 years of age (P = .056). CONCLUSIONS: We conclude that the incidence of asthma in this population of relatively young, well educated, white adults is approximately 3.4 per 1000 per year and that newly diagnosed asthma was more common in women and in those < 30 years of age.

Adolescent↗
PubMed1996

Evaluation of IgA measurements as a method for detecting maternal blood contamination of cord blood samples.

Several studies have evaluated the value of cord blood IgE concentrations for predicting the risk of allergic disease in children. In all of these studies it is necessary to exclude cord blood samples in which the IgE may be falsely elevated due to admixing of maternal and fetal blood during parturition. The most common method for detecting mixing of fetal and maternal blood is measurement of cord blood IgA concentrations. We have examined the theoretical basis of IgA measurements for detecting maternal blood contamination and reexamined our own data to evaluate IgA measurements. Our data suggest that the average IgA concentration of 28.2 micrograms/ml used in previous studies may not adequately exclude contaminated cord blood sample. Failure to reject contaminated cord blood samples would reduce the positive predictive value of cord blood IgE measurements.

Blood Grouping and Crossmatching↗
PubMed1996

Parental history of atopic disease and concentration of cord blood IgE.

BACKGROUND: A family history of atopy, and cord blood immunoglobulin E concentration, have been shown to be predictors of atopic disease in children. Several studies have suggested that parental atopy may be related to newborn immunoglobulin E. OBJECTIVE: The purpose of our analysis was to evaluate whether parental history of allergic disease was associated with cord blood immunoglobulin E concentration. METHODS: The study subjects were from a defined population of 777 newborns delivered between 1987 and 1989. The mothers of these children completed a questionnaire during pregnancy concerning themselves and the child's father, including parental history of physician diagnosis of allergic diseases (allergies, hay fever and asthma). Total immunoglobulin E levels were quantitated in cord blood samples with an enzyme-linked immunoassay. RESULTS: Median cord blood immunoglobulin E concentration was higher among infants whose mothers had a history of atopic disease, particularly for those with a history of asthma (P < 0.022) and allergen immunotherapy (P < 0.016) vs infants whose mothers had no history of any atopic disease. Comparing all babies with a maternal history of asthma, to babies where neither parent had a history of any atopic disease, the median cord blood immunoglobulin E was significantly higher (0.36 IU/mL vs 0.21 IU/mL; P < 0.009). This association was found only among female infants (0.49 IU/mL vs 0.20 IU/mL; P < 0.001). CONCLUSION: Maternal, but not paternal, history of atopic disease was associated with an elevated immunoglobulin E among newborns. For maternal asthma, this association was only evident in infant girls.

Enzyme-Linked Immunosorbent Assay↗
PubMed1995

Cat shedding of Fel d I is not reduced by washings, Allerpet-C spray, or acepromazine.

BACKGROUND: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied. OBJECTIVE: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats. METHODS: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic-acrylic chamber and air sampler. RESULTS: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change +/- SD: washing; 487.6 +/- 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 +/- 871.6 mU per 30 minutes, p = 0.46 acepromazine; -620.6 +/- 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72). CONCLUSIONS: Out data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats.

Acepromazine↗
PubMed1995

Prevalence of latex-specific IgE antibodies in patients being evaluated for allergy.

OBJECTIVE: The purpose of this study was to determine the prevalence of detectable latex-specific IgE in patients being evaluated for allergy. METHODS: The AlaSTAT assay was used to test for latex-specific IgE in 200 consecutive serum samples sent to our laboratory for total IgE levels. Samples sent for latex-specific IgE were excluded. The population studied included 87 males and 113 females ranging in age from 1 to 82 years of age. Inhibition studies with a latex extract were performed on all positive samples. Chart reviews and questionnaires provided information regarding risk factors for latex allergy and reactions to latex. RESULTS: Twenty-four (12%) subjects were positive for latex-specific IgE. Seventeen of the 24 positive subjects (70.8%) were < 18 years of age and all of the strongly positive subjects (7 or 3.5%) were < 18 years of age. The geometric means for total IgE for the latex positive and negative subjects were 351 IU/mL and 80 IU/mL respectively, P < .001. The mean percent inhibition with latex was 66%. Chart reviews and questionnaires revealed only 2 of 24 positive subjects were in high risk groups, none of the positive subjects had any history of reactions to latex, and 22 (91.6%) had evidence of atopic disease. CONCLUSION: In vitro tests may detect latex specific IgE in atopic individuals, especially children, with no history of recurrent latex exposure and no history of adverse reactions to latex.

Adolescent↗
PubMed1995

Mechanisms in adverse reactions to food. The whole body.

Both immunologic and non-immunologic mechanisms can provoke systemic reactions following food ingestion. Histamine is the only mast cell mediator which has been demonstrated to be elevated in the serum as a result of systemic allergic reactions to food. In individuals highly sensitive to foods, airborne exposure to food allergens can produce anaphylactic reactions. Crossreacting allergens present in some foods and in natural rubber latex can lead to systemic reactions following either latex exposure or food ingestion.

Anaphylaxis↗
PubMed1994

The appropriate use of skin testing and allergen immunotherapy in young children.

Immunotherapy is clearly effective in the treatment of allergic rhinitis and Hymenoptera sensitivity and probably effective in the treatment of asthma. Few studies evaluate the risks and benefits of immunotherapy in young children. Current evidence suggests that young children are at increased risk for systemic reactions from immunotherapy. Furthermore, immunotherapy or adverse reactions resulting from immunotherapy may result in significant psychologic problems. The potential risks of immunotherapy would be justified if immunotherapy were demonstrated to be safe and additive to other therapies. Immunotherapy might be particularly effective in treating or helping to prevent house dust mite- or cockroach-associated asthma. Until the efficacy of immunotherapy is demonstrated in young children, we agree with the European Academy of Allergology and Clinical Immunology position that immunotherapy in young children is relatively contraindicated.

Allergens↗
PubMed1994

Multi-centre comparison of ABBOTT MATRIX Aero to Pharmacia Standard RAST, Modified RAST and skin puncture tests.

ABBOTT MATRIX Aero is an enzyme immunoassay which measures specific IgE antibodies to 14 individually calibrated airborne allergens using a single serum specimen. In this study, ABBOTT MATRIX performance was evaluated in comparison to the results of skin puncture test and the Standard and Modified RAST procedures. The ABBOTT MATRIX demonstrated overall sensitivity of 89% vs. Standard RAST and Modified RAST, with specificity greater than 92% vs. both methods. ABBOTT MATRIX sensitivity vs. skin test (71%) exceeded that of the Standard and Modified RAST procedures (62% and 67% respectively). Positive results reported by ABBOTT MATRIX but not RAST were corroborated by skin test results for 3 of 5 allergens evaluated. All in vitro systems demonstrated specificity of approximately 90% vs. skin test. The ABBOTT MATRIX system provided results which compared favorably with the results of skin test and RAST, but required less hands-on time to obtain quantitative specific IgE measurements to multiple allergens.

Adolescent↗
PubMed1994

Somatic mosaicism for a newly identified splice-site mutation in a patient with adenosine deaminase-deficient immunodeficiency and spontaneous clinical recovery.

Absent or severely reduced adenosine deaminase (ADA) activity produces inherited immunodeficiency of varying severity, with defects of both cellular and humoral immunity. We report somatic mosaicism as the basis for a delayed presentation and unusual course of a currently healthy young adult receiving no therapy. He was diagnosed at age 2 1/2 years because of life-threatening pneumonia, recurrent infections, failure of normal growth, and lymphopenia, but he retained significant cellular immune function. A fibroblast cell line and a B cell line, established at diagnosis, lacked ADA activity and were heteroallelic for splice-donor-site mutation in IVS 1 (+1GT-->CT) and a missense mutation (Arg101Gln). All clones (17/17) isolated from the B cell mRNA carried the missense mutation, indicating that the allele with the splice-site mutation produced unstable mRNA. In striking contrast, a B cell line established at age 16 years expressed 50% of normal ADA; 50% of ADA mRNA had normal sequence, and 50% had the missense mutation. Genomic DNA contained the missense mutation but not the splice-site mutation. All three cell lines were identical for multiple polymorphic markers and the presence of a Y chromosome. In vivo somatic mosaicism was demonstrated in genomic DNA from peripheral blood cells obtained at 16 years of age, in that less than half the DNA carried the splice-site mutation (P < .002, vs. original B cell line). Consistent with mosaicism, erythrocyte content of the toxic metabolite deoxyATP was only minimally elevated. Somatic mosaicism could have arisen either by somatic mutation or by reversion at the site of mutation. Selection in vivo for ADA normal hematopoietic cells may have played a role in the return to normal health, in the absence of therapy.

Adenosine Deaminase↗
PubMed1993

Anaphylaxis after ingestion of beignets contaminated with Dermatophagoides farinae.

A 48-year-old man was evaluated for anaphylaxis associated with ingestion of beignets prepared from a commercial mix. Microscopic examination of the patient's beignet mix revealed live Dermatophagoides farinae. Another unopened box from the same source was not infested. Skin test results to aeroallergens and foods, including all beignet mix ingredients, were positive only to D. farinae and D. pteronyssinus extracts. Skin prick test results to an infested mix extract (1:5 wt/vol) were also positive, but no reaction was observed with noninfested mix extract. ELISA inhibition studies demonstrated significant inhibition of the patient's serum binding to D. farinae strips by infected mix extract. Parallel inhibition curves were produced by the infested mix extract and a commercial D. farinae extract. Noninfested mix extract showed no inhibition. RAST analysis with beignet mix discs showed significant binding of the patient's serum IgE to infested mix discs but not to noninfested mix discs. RAST inhibition studies revealed more than 86% inhibition of binding of the patient's IgE to infested mix discs by infested mix extract and D. farinae extract. No inhibition was observed with noninfested mix or 5% fetal calf serum-phosphate-buffered saline. We conclude that the allergen to which the patient reacted was most likely D. farinae and that ingestion of D. farinae may cause anaphylaxis in sensitive persons.

Allergens↗
PubMed1993

Relationship between dust mite allergen and human IgA in house dust samples.

Previous investigators have mentioned that human IgA is found in house dust. IgA has also been reported to be present on human skin and hence in human dander. If human dander is the primary source of food for house dust mites, a relationship would be expected between IgA and dust mite allergen (Der f I) concentrations. We wished to learn whether IgA was consistently detectable in house dust and whether IgA and dust mite allergen concentrations were related. Dust samples were collected from the bedrooms of infants enrolled in a prospective study designed to evaluate the relationship between early allergen exposure and childhood allergic disease. One hundred eighty samples were studied: 50 samples were the initial samples collected from the first 50 infants enrolled, 120 samples were monthly samples obtained from 10 other homes, and 10 additional samples were randomly selected for extraction in a nonprotein containing buffer to determine the percentage of total extractable dust protein contributed by IgA. Finally, nine commercial house dust extracts were studied to learn whether they were similar to the dust samples from study houses. Enzyme linked immunosorbent assays (ELISAs) were used to measure human IgA, human secretory IgA (sIgA) and Der f I concentrations in all of the dust extracts. We found that IgA was consistently present in house dust samples ranging from 3.2 to 2,396 micrograms of IgA per gram of dust. A strong correlation (r = .90) was found between IgA and sIgA concentrations. IgA constituted 0.27% to 6.04% of the total protein in dust samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollution↗
PubMed1993

Ubiquitous presence of cat allergen in cat-free buildings: probable dispersal from human clothing.

Fel d I has been found in almost all houses investigated, including those in which cats have never been present. These observations have not been explained. We measured Fel dI in samples of carpet dust from ten newly built model homes, 14 occupied homes, six allergists' offices, five hospital corridors, and three shopping mall stores. We also measured Fel d I on T-shirts of persons with and without cats. Measurable amounts of Fel d I were found in all the dust samples. Fel d I found in older model homes exceeded that found in newer model homes (P < .05). The amounts of Fel d I found in allergists' offices, hospital corridors, and retail stores were similar to the amounts found in occupied homes without cats. Fel d I was found in all T-shirts sampled and increased with increasing exposure to cats. Our findings confirm and extend previous reports of the ubiquitous presence of cat allergen and are consistent with the hypothesis that Fel d I is carried into cat-free buildings on the clothing of people exposed to cats.

Allergens↗
PubMed1992

Occupational asthma in a beet sugar processing plant.

A patient with occupational asthma in the beet sugar processing industry is described. Symptomatology, skin testing, immunologic testing, and specific bronchoprovocation testing indicate exposure to moldy sugar beet pulp was the cause of the patient's occupational asthma. Cooperation between the treating physician and public health authorities is encouraged.

Adult↗
PubMed1992

Evidence of cross-reactivity between olive, ash, privet, and Russian olive tree pollen allergens.

In a clinical investigation, 103 Michigan residents with symptoms suggestive of allergic rhinitis or asthma were skin tested with olive (Olea europaea) pollen extract. Nineteen had positive reactions. Since the olive tree is not native to nor grown in Michigan, this study was undertaken to determine whether the skin test reactivity was the result of cross-reactivity among tree pollen allergens. ELISAs were developed to measure olive, ash (Fraxinus americana), privet (Ligustrum vulgare), and Russian olive (Elaeagnus angustifolia) specific IgE antibodies. Inhibition studies were performed to determine whether pollen extracts from each of these tree species could inhibit IgE antibody binding to olive extracts. Eleven of the 19 skin test-positive patients were olive-ELISA positive, eight either were ELISA-positive to ash, seven to privet and ten to Russian olive. There were significant correlations between the ELISA results to olive and each of the other three pollens. The inhibition studies demonstrated that all three of the tree pollens were capable of inhibiting the binding of IgE to olive extract in a dose-response fashion. IgE-immunoblot studies demonstrated several proteins common to olive, ash, and privet. Twelve of the olive skin test-positive patients were contacted and 75% were exposed to one or more of the studied trees in their yards. Five patients had traveled to areas where olive trees are grown. We conclude that there is a high degree of cross-reactivity among allergens from native Michigan trees and from olive trees. This cross-reactivity is the most likely reason for skin test reactivity to olive pollen extract in Michigan.

Allergens↗