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Biomedical subjects

R A Simon

Publications and source records attributed to R A Simon.

At least 55 records · Page 3Linked to original sources
PubMed1983

Occupationally acquired vibratory angioedema with secondary carpal tunnel syndrome.

After several years of occupational exposure to vibration, a man developed episodic vibratory hand swelling, erythema, and pruritus. He subsequently developed symptoms compatible with carpal tunnel syndrome, but his median nerve conduction velocity remained normal. After experimental vibration of the forearm, plasma histamine levels in the ipsilateral antecubital vein rose in association with localized angioedema and slowed median nerve conduction velocity. There was no evidence of other causes of angioedema. Occupational exposure to vibration may predispose to the development of vibratory angioedema, which may predispose to intermittent compression neuropathy.

Adult↗
PubMed1982

Histamine contamination of pokeweed mitogen.

The histamine content of commercial preparations of pokeweed mitogen was measured by amino acid analysis technique, automated fluorometry, and bioassay employing the guinea pig ileum. Ten samples from 5 companies were examined and found to contain between 0.026 micrograms and 167.5 micrograms of histamine per ml of solution. The protein content of 9 of these putative 5 mg samples measured by folin assay and by amino acid analysis varied from 0.56 to 4.4 mg. Their amino acid compositions were similar, except for notable variations in 3 of the 16 residues quantitated.

Amino Acids↗
PubMed1982

Aspirin desensitization in aspirin-sensitive asthmatic patients: clinical manifestations and characterization of the refractory period.

Thirty aspirin-sensitive asthmatic patients underwent incremental, oral aspirin challenge until a "positive reaction" (delta FEV1 greater than or equal to 25%) occurred. After this reaction, aspirin was readministered in an attempt to achieve "desensitization." This was defined as the ability of the patient to ingest 650 mg of aspirin without experiencing upper or lower respiratory-tract symptoms or a decrease in lung function. To determine the "refractory period" following aspirin desensitization, patients were rechallenged after various intervals (days) without aspirin until a positive reaction recurred. All 30 aspirin-sensitive asthmatic patients were successfully desensitized to aspirin. Individual patient refractory periods ranged from less than 2 days to greater than 5 days, with most patients gradually returning to sensitivity between 2 to 4 days. Cross-densensitization with indomethacin and other nonsteroidal anti-inflammatory drugs was also demonstrated. These studies show that aspirin desensitization can be safely achieved in aspirin-sensitive asthmatic patients; however, this desensitization will gradually disappear over several days when additional aspirin is withheld.

Adolescent↗
PubMed1981

Sensitivity to ingested metabisulfites in asthmatic subjects.

While ingesting selected foods and drinks in restaurants, four asthmatic patients reported the sudden onset of severe wheezing and associated anaphylactoid symptoms and signs. Single-blind placebo and potassium metabisulfite (K2S2O5) oral challenges documented asthmatic responses 15 to 30 min after ingestion of K2S2O5. Laboratory investigations failed to demonstrate specific reaginic antibody recognition of K2S2O5 in these patients. Furthermore, their peripheral basophils did not release histamine during in vitro challenges with K2S2O5. It seems likely that additional asthmatic subjects have such sensitivities but are currently assumed to have "food allergies." Such individuals can be suspected of having this sensitivity by history, and oral K2S2O5 challenges can identify asthmatics who are sensitive.

Adult↗
PubMed1981

Increase of lymphocytes with Fc receptors for IgE in patients with allergic rhinitis during the grass pollen season.

Peripheral blood lymphocytes from 10 nonallergic donors and 7 patients suffering from seasonal allergic rhinitis and receiving desensitization therapy were analyzed by rosette assays for Fc receptors for IgE (Fc epsilon R) and IgG (Fc gamma R) before, during and after the grass pollen season. Six of seven patients had moderately elevated IgE levels (330 +/- 268 IU/ml), all had high titers of skin sensitizing antibodies to grass pollens and serum IgE antibodies as measured by radio-allergosorbent tests (RAST). Seven of the nonallergic donors had 2-30 IU/ml IgE and negative RAST, whereas three had 91-267 IU/ml IgE and two were RAST positive to the grass pollens. In March, when the patients were asymptomatic, the mean +/-SD of the Fc epsilon R+ lymphocytes did not significantly differ from the nonallergic control group: nonallergic Fc epsilon R+ 1.2 +/- 0.9% (29 +/- 20/,mm3), allergic Fc epsilon R+ 2.0 +/- 3.1% (48 +/- 52/mm3). In contrast, during the grass pollen season in May and June, when the patients developed symptoms of allergic rhinitis, they had significantly (P less than 0.01) more Fc epsilon R+ lymphocytes than the controls: nonallergic Fc epsilon R+ 1.7 +/- 1.9% (40 +/- 46/mm3), allergic Fc epsilon R+ 4.7 +/- 1.2% (134 +/- 69/mm3). In the postpollen period, August-October, most of the patients again had low numbers of Fc epsilon R+ lymphocytes: nonallergic Fc epsilon R+ 1.4 +/- 0.9% (26 +/- 13/mm3), allergic Fc epsilon R+ 2.1 +/- 1.9% (62 +/- 82/mm3). The nonallergic control donors with elevated IgE levels and positive RAST always had low numbers of Fc epsilon R+ lymphocytes. In contrast, two other nonallergic donors, who had a 2-7 IU/ml IgE and negative RAST, showed significant increases of Fc epsilon R+ lymphocytes over several weeks during the grass pollen season. No statistically significant changes in Fc gamma R+ lymphocytes occurred in both nonallergic and allergic donors. The total and specific IgE serum levels did not vary much in the nonallergic donors and patients during the period of study and any changes that did occur did not correlate with the changes in Fc epsilon R+ lymphocytes. The data demonstrate that Fc epsilon R+ peripheral blood lymphocytes increase in allergic patients during natural antigen exposure and active disease in the absence of measurable increases of total and specific serum IgE. Because two nonallergic control donors also had temporary increases of Fc epsilon R+ lymphocytes, an increase of peripheral blood Fc epsilon R+ lymphocytes may be a sensitive indicator of an ongoing IgE immune response.

Humans↗
PubMed1980

Efficacy of troleandomycin in outpatients with severe, corticosteroid-dependent asthma.

Sixteen severe, corticosteroid-dependent yet resistant outpatient asthmatics were treated with troleandomycin (TAO), a macrolide antibiotic, in an attempt to both induce a clinical remission and reduce methylprednisolone requirements. Within the first 2 wk of initiating TAO therapy, 50% of the patients experienced a greater than 20% increase in forced expiratory volume in 1 sec (FEV1) and 80% noted a greater than 20% increase in forced vital capacity between 25% and 75% (FVC 25%-75%). Maximal increases in FEV1 and FVC 25%-75% were noted in all patients within the first 6 wk on TAO and methylprednisolone. There was a concomitant clinical improvement in all patients. Corticosteroid-induced side effects, gastrointestinal tract discomfort, and elevated serum glutamic pyruvic transaminase (SGPT) were common yet generally transient during TAO and methylprednisolone therapy. After a 4- to 18-mo follow-up 15/16 patients were well-controlled on TAO and methylprednisolone. Methylprednisolone requirements were reduced at least four- to fivefold in most patients during TAO therapy. Normal morning serum cortisol levels were documented after varying intervals in most patients when both TAO (250 mg) and methylprednisolone (4 to 16 mg) could be reduced to alternate-day administration. Only one patient was forced to discontinue therapy due to side effects. The present study extends the effectiveness of TAO therapy to ambulatory asthmatics, establishes a clinical strategy that maximizes benefit/risk factors, and provides practical guidelines for the long-term use of TAO and methylprednisolone.

Adolescent↗
PubMed1980

Aspirin-sensitive asthma: tolerance to aspirin after positive oral aspirin challenges.

Two aspirin-sensitive asthmatic patients underwent oral aspirin challenges for investigative purposes. Folowoing the expected respiratory reaction to aspirin, the patients became refractory to the further adverse effects of aspirin. Additionally they began taking 325 mg aspirin per day, and after 6 and 8 mo aspirin dosage was increased to 650 mg per day. We have noted an improvement in their rhinitis and asthma during this open drug trial. Furthermore, maintenance systemic corticosteroids have been reduced in one patient and discontinued in the other without a decline in lung function values. If these intitial observations are found in a larger number of aspirin-sensitive asthmatic patients, changes in our understanding of the pathogenesis of rhinosinusitis-asthma-aspirin syndrome would follow, and treatment for such asthmatic patients might be improved.

Administration, Oral↗
PubMed1979

Lymphocytes with immunoglobulin E Fc receptors in patients with atopic disorders.

Lymphocytes from normal nonallergic donors and patients with atopic disorders were analyzed for subpopulations bearing Fc receptors for immunoglobulin (Ig)E (Fc(epsilon)) and IgG (Fc(gamma)), surface IgM (sIgM) and IgD (sIgD), and for T cells forming spontaneous rosettes with sheep erythrocytes (E). The patients were divided into three groups according to serum IgE concentrations and systemic corticosteroid treatment. Group I consisted of 12 atopic patients with either normal or moderately increased IgE levels up to 4,000 U/ml. Four patients of group II and three of group III had 10,500-31,000 U/ml and severe atopic dermatitis. Patients of group III, but not I and II, were receiving corticosteroids systemically. The percentage (mean +/-SD) and total number of Fc(epsilon) (+) lymphocytes were 1.2+/-0.5%, 41+/-24/mm(3) in 12 normals; 1.6+/-0.9%, 59+/-43/mm(3) in patients of group I: 7.0+/-2.0%, 187+/-67/mm(3) in group II; and 0.3+/-0.1%, 13+/-5/mm(3) in patients of group III. The increase in group II and decrease in group III of Fc(epsilon) (+) cells were statistically significantly different from the normal persons and patients of group I. In contrast, the patients did not differ significantly from the donors in sIgM(+), sIgD(+), Fc(gamma) (+), and E(+) cell populations. As shown by depletion of sIg(+) cells in four patients with atopic disorders, the great majority of the Fc(epsilon) (+) lymphocytes were B cells. However, two patients with elevated Fc(epsilon) (+) cell numbers had small numbers of mixed E- and Fc(epsilon)-rosetting cells, presumably T cells. Two patients of group II were examined during an acute herpes simplex infection. Both showed an congruent with80% decrease of Fc(epsilon) (+) cells at that time. No apparent correlation between numbers of Fc(epsilon) (+) cells and IgE level existed in patients of group I. Injection of an IgE myeloma protein into two monkeys did not significantly change their percentages of Fc(epsilon) (+) lymphocytes. The data indicate that Fc(epsilon) (+) lymphocytes are increased in patients with markedly elevated serum IgE and severe atopic disease, suggesting that these cells may be involved in the regulation and(or) synthesis of IgE antibody formation.

Adrenal Cortex Hormones↗
PubMed1978

Increased in vitro histamine release by radiographic contrast media in patients with history of incompatibility.

This study was designed to compare in vitro leucocyte histamine release in patients with a history of previous radiographic contrast media (RCM) reactions and normal controls. Peripheral leucocytes of ten patients with a positive history of RCM imcompatibility and nineteen normal volunteers were stimulated in vitro with different RCM in different concentrations and the amount of histamine released was measured in the supernatant. There was a significant increase in histamine release induced by RCM in low doses (0.02-0.1 M) in the patients as compared to the normals. At the high doses (0.2-0.3 M), no significant differences were found. Leucocytes from four of the patients were stimulated preferentially by the dye responsible for the incompatibility. Six patients showed no such preference. The increased "releasability" of the patients' leucocytes could not be transferred by serum. Normal leucocytes, when incubated with serum from "high releasing" patients did not show increased histamine release after stimulation with the respective dye. It is suggested that an excessive non-immunological response of basophil leucocytes to RCM stimulation might, in part, account for the adverse clinical reactions observed. Furthermore, leucocyte histamine release might be a useful diagnostic tool for detecting patients with a high risk of developing contrast media reactions.

Adult↗