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D K Ledford

Publications and source records attributed to D K Ledford.

At least 19 recordsLinked to original sources
PubMed2001

Prevalence of upper respiratory symptoms in patients with symptomatic gastroesophageal reflux disease.

UNLABELLED: This study evaluated the prevalence of upper respiratory symptoms (URS) among patients with symptomatic gastroesophageal reflux disease (GERD). Seventy-four subjects with heartburn completed a URS questionnaire before dual-probe, 24-h esophageal pH monitoring. The URS questionnaire was also completed by 74 normal volunteers without previous or current symptoms of GERD. Esophageal pH monitoring results were classified as normal, distal, or proximal and distal gastroesophageal reflux using standardized criteria. Mean URS scores (+/- SD) were 8.31 +/- 3.98 in the 52 subjects with GERD and 4.57 +/- 3.57 in the 22 subjects with negative pH probe studies, p = 0.02. Subjects with negative pH probe studies and normal volunteers scored similarly on the URS questionnaire. Reflux episodes/24 h correlated with URS scores, r = 0.47, p = 0.0001. Seventy-five percent of subjects with upper reflux, 68% of subjects with lower reflux, 36% of subjects with normal esophageal pH studies, and 9% of normal volunteers reported laryngeal symptoms for at least 5 d/mo. Sixty-nine percent of subjects with upper reflux, 50% of subjects with lower reflux, 31% of subjects with normal pH studies, and 14% of normal volunteers reported nasal symptoms for at least 5 d/mo. URS are frequent among subjects with GERD. KEYWORDS: rhinitis; upper airway; gastroesophageal reflux

Adult↗
PubMed2001

House dust mite, cat, and cockroach allergen concentrations in daycare centers in Tampa, Florida.

BACKGROUND: Allergen exposure in early childhood is a risk factor for sensitization and the development of asthma. Studies performed in Europe, New Zealand, and Singapore indicated the presence of indoor allergens in childcare centers and schools. However, the importance of indoor allergens in daycare centers in humid and warm regions of the world is not known. OBJECTIVE: To measure total mite counts, Der p 1, Der f 1, Fel d 1, and Per a 1 allergens in dust samples and mite allergen airborne concentrations in daycare centers in Tampa, Florida, United States. METHODS: Twenty daycare centers were surveyed for mite, cat, and cockroach allergens in Tampa, FL. One dust and two air samples (one during the day and one during the night) were collected in each center. Dust samples were extracted and analyzed for mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Per a 1) allergens. Mite airborne allergen concentrations were analyzed by RAST inhibition and expressed in standardized mite allergen units per m3 of air (AU/m3). RESULTS: Mites were identified in 15 samples, and concentrations ranged from 10 to 1,200 mites/g (298 +/- 355.2). The most prevalent mite species was Dermatophagoides pteronyssinus ( Der p 1). Der p 1 and/or Der f 1 were detected in 10 daycare centers. Der p 1 was detected in eight centers and ranged from I to 21.8 microg/g of dust (5.4 +/- 6.9); Der f 1 was detected in 3 centers and ranged from 0.2 to 2.1 microg/g of dust (1.3 +/- 0.9). Per a 1 and Fel d 1 were detected in all centers in small quantities; Per a 1 ranged from 8 to 1,806 ng/g (263.1 +/- 449.7) and Fel d 1 from 0.2 to 120 U/g of dust (16.6 +/- 31.7), respectively. Airborne mite allergen was detected in 18 centers and ranged from 0.01 to 2.7 AU/m3 during the day (0.2 +/- 0.6) and from 0.01 to 0.12 AU/m3 during the night (0.06 +/- 0.03), P = 0.001. CONCLUSIONS: Mite, cat, and cockroach allergens are present in daycare centers in Tampa, FL. Mite allergen concentrations exceeded levels that have been associated with sensitization and symptoms in allergic subjects in 40% of these centers.

Allergens↗
PubMed1998

Recent findings in asthma likely to impact patient care.

The management of asthma is becoming increasingly complex as more pharmacologic agents become available and we gain increased understanding of the pathogenetic processes of asthma and the risks for potentially irreversible airway remodeling that might be increased by suboptimal management and interactions with concomitant disease states such as gastroesophageal reflux. Although physicians now have greater responsibility to make use of this increasing knowledge to provide more effective management for their asthma patients, they also have a greater opportunity to increase the overall quality of life of patients under their care.

Adrenergic beta-Agonists↗
PubMed1997

Immunologic aspects of vasculitis and cardiovascular disease.

The immunologic cardiovascular diseases are a heterogeneous group of conditions. Many of these entities are associated with serious morbidity and mortality resulting from cardiac impairment, ischemic complications, or organ dysfunction, particularly of the kidneys, lung, and nervous system. The systemic nature of these conditions, coupled with vague symptoms and nonspecific initial physical findings, makes the differential diagnosis complicated. Research has identified specific mediators and primary origins in some conditions, with infections often being responsible. Immunosuppressive therapy, despite the potential complications, has improved the prognosis of some of the more serious immunologic cardiovascular diseases. Improvement in the treatment of immunologic cardiovascular diseases awaits identification of additional causes, improved definition of host factors that predispose an individual to develop these conditions, and better understanding of the immune dysregulation responsible for the progression of disease. The potential pathophysiologic role of immunologic mechanisms in common disorders such as congestive heart failure and atherosclerosis is intriguing and offers the possibility of novel therapies in these prevalent conditions.

Cardiovascular Diseases↗
PubMed1994

Comparison of oral pulse methotrexate with placebo in the treatment of severe glucocorticosteroid-dependent asthma.

BACKGROUND: This study compared the efficacy of weekly oral administration of methotrexate and placebo in treatment of 24 subjects with chronic glucocorticosteroid-dependent asthma. METHODS: The 33-week randomized, double-blind, placebo-controlled crossover trial compared once weekly 15 mg doses of methotrexate with placebo. At the time of entry, the subjects' mean dosage of prednisone was 23.8 mg/day (range, 12.5 to 85 mg) and glucocorticosteroid therapy had been used continuously for a mean duration of 78 months (range, 5 to 360 months). RESULTS: Of the 21 subjects who completed the study, 13 tolerated lower daily prednisone doses during methotrexate treatment compared with placebo. When treated with methotrexate, subjects required 14.2% less prednisone than when treated with placebo (p = 0.0447), their subjective symptom scores improved 21.4% (p < 0.05), and mean forced expiratory volume in 1 second values tended to improve. Mean serum theophylline levels did not change significantly between the methotrexate and placebo arms of the study. Adverse effects were minimal, with nausea and headache occurring twice as often during methotrexate therapy compared with placebo. CONCLUSION: Short-term, low-dose, pulse therapy with orally administered methotrexate results in a decrease in the daily glucocorticosteroid requirement in a majority of subjects with severe asthma and is accompanied by improvement in subjective symptom scores without unacceptable side effects or deterioration of pulmonary function.

Administration, Oral↗
PubMed1994

Indoor allergens.

Explore the source record for details and available documents.

Air Pollution, Indoor↗
PubMed1992

Immunologic aspects of cardiovascular disease.

The spectrum of vasculitis is diverse, and numerous entities do not fit the aforementioned broad categories. Examples of these include Buerger's disease; vaso-occlusive vasculitis of the lower extremities associated with cigarette smoking; Behçet's disease, which is prevalent in the Orient and Middle East and is characterized by recurrent aphthous stomatitis, genital ulcerations, uveitis, meningoencephalitis, and phlebitis; and isolated central nervous system vasculitis, a rare disease with a poor prognosis that primarily affects intracranial arteries without a systemic acute-phase response. Improvement in the classification and definitive therapy of vasculitis awaits identification of etiologic agents and definition of host factors and the immune response responsible for the pathology.

Acute Disease↗
PubMed1990

Serum IgE and human immunodeficiency virus (HIV) infection.

Human immunodeficiency virus infection is characterized by a progressive depletion of helper T-lymphocytes and, like allergic diseases, is associated with altered T cell regulation. Total serum IgE was measured in 67 infected male subjects, 27 uninfected heterosexual male subjects, and 18 uninfected homosexual male subjects. The mean IgE level (132 IU/ml) of infected subjects with a helper T-lymphocyte number less than or equal to 200/mm3 was significantly greater than mean IgE levels of the uninfected heterosexual (38 IU/ml) and homosexual (35 IU/ml) groups. IgE levels were inversely related to both helper T cell and suppressor/cytotoxic T cell numbers but not to IgG or IgA levels. The increase in IgE was not a reflection of an increased prevalence of atopic disease (allergic asthma, allergic rhinitis, or atopic dermatitis) in the infected subjects. The elevation of IgE may be related to a difference among the groups in T cell production of IgE regulatory lymphokines.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Allergens of the imported fire ant.

A whole body extact (WBE) was prepared by saline extraction of ground imported fire ants (IFA). A serum pool from rabbits immunized with the WBE elicited 31 precipitates on crossed immunoelectrophoresis. Crossed radioimmunoelectrophoresis was performed with sera from 26 RAST IFA-positive subjects, 24 of whom were known for clinical hypersensitivity to IFA and two subjects, known to be hypersensitive to yellow jacket. Radiostaining was obtained to 14 precipitates, some of which were judged to be partially identical. Thus, six apparently different allergen groups could be identified. Two of these fulfilled arbitrary criteria of major allergens. Three of the IFA WBE allergens were easily identified in crossed immunoelectrophoresis of a commercially obtained IFA-venom preparation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the IFA WBE demonstrated protein bands with molecular weight ranging from 10,000 to 200,000 daltons. An immunoblotting technique with nitrocellulose paper strips revealed binding of human IgE from hypersensitive subjects to four different bands (either single bands or clusters of proteins of similar molecular weight) with molecular weights ranging from 13,000 to 42,000 daltons. It is a notable finding that these insect allergens thus were of a similar size as important aeroallergens.

Allergens↗
PubMed1987

Immunologic aspects of cardiovascular disease.

The current classification scheme of the diverse inflammatory cardiovascular diseases permits a clinical staging and facilitates prognostic assessment and therapeutic decision making. Ultimately, improvement in the classification of and definitive therapy for these conditions awaits better definition of the interaction among specific etiologic agents, host factors, and the immune system responsible for these diseases.

Cardiovascular Diseases↗