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Biomedical subjects

H A Lyons

Publications and source records attributed to H A Lyons.

At least 37 records · Page 2Linked to original sources
PubMed1977

A comparative study of subcutaneously administered terbutaline and epinephrine in the treatment of acute bronchial asthma.

Terbutaline, a new bronchodilator drug reported to have selective affinity for beta 2-adrenergic receptors, was compared with epinephrine in the treatment of 49 adult subjects with acute bronchial asthma. Under double-blind conditions, 24 subjects received 1.0 mg of terbutaline sulfate, and 25 subjects received 0.5 mg of epinephrine hydrochloride subcutaneously. Spirometric measurements, heart rate, and blood pressure, as well as subjective responses, were recorded prior to, and then at 5, 15, 30, 60, and 120 minutes after administration of the drug. The results indicate that terbutaline is an effective bronchodilator drug in subjects with acute asthma; however, the heart rate rose significantly after administration of terbutaline, with a maximal increase of 25 percent above control. Review of the literature reveals that tachycardia is a consistent finding when subcutaneous doses of terbutaline in excess of 0.25 mg are administered. Stimulation of beta 1-adrenergic receptors in the heart appears to be the most important factor involved in this response. A lesser cardioaccelerator effect was observed after administering epinephrine in a dose producing an equivalent degree of bronchodilatation.

Acute Disease↗
PubMed1977

Occurrence of lung granulomas in patients with stage I sarcoidosis.

Granulomas were found in the lungs of 21 consecutive patients with stage I sarcoidosis who underwent open lung biopsy. The extent of granulomatous disease and fibrosis was significantly less (P less than .05) than seen in open lung biopsies from larger groups of patients with stage II and stage III sarcoidosis. The results of this study support what had previously been widely suspected: that is, if sufficient lung tissue is studied microscopically, granulomas will be found in the lungs of all patients having sarcoidosis with mediastinal lymphadenopathy but not radiographically demonstrable lung abnormalities.

Granuloma↗
PubMed1977

Serum angiotensin converting enzyme in sarcoidosis: clinical significance.

The elevated activity of serum angiotensin converting enzyme (ACE) in sarcoidosis was usually reduced during steroid therapy but remained above the normal value (52 nmol-min-1-ml-1) in approximately a third of patients during the first year of therapy. ACE was elevated in 5 of 10 patients treated with steroids for at least four years. It was significantly higher in untreated patients (placebo group), who were subsequently placed on steroid therapy because of clinical deterioration, than in those remaining on placebo therapy. In general ACE tended to diminish with increasing duration of disease. The results suggest that serial study of ACE may be useful in the clinical management of sarcoidosis, including assessment of the degree of activity, the need for steroid therapy, therapeutic result and the prognosis.

Adult↗
PubMed1977

Increased serum angiotensin converting enzyme activity in sarcoidosis.

The activity of serum angiotensin converting enzyme (ACE), assayed fluorometrically with the substrate hippuryl-L-histidyl-L-leucine was significantly higher in 116 patients with sarcoidosis than in 415 patients with other diseases--pulmonary and nonpulmonary--and in 58 normal subjects. Serum ACE was elevated in 59% of 46 recently diagnosed, untreated patients with sarcoidosis and was significantly reduced following steroid therapy in three patients with sarcoidosis, but in only one of four patients treated with placebos. The results suggest that elevated serum ACE activity is a valuable, although not absolutely specific, diagnostic indicator of sarcoidosis. It should be stressed that a normal value does not rule out the disease, and that steroid therapy tends to reduce the serum ACE activity.

Adult↗
PubMed1977

Granulomatous pulmonary angiitis in sarcoidosis.

The occurrence and morphologic aspects of granulomatous pulmonary angiitis were evaluated in open lung biopsy specimens from 128 patients with sarcoidosis. All of the specimens showed parenchymal granulomas characteristic of sarcoidosis, and in 88(69%), granulomatous angiitis was seen. In the speclimens that exhibited granulomatous angiitis, venous involvement was mos common, seen in 92% of the cases. In 61% of these biopsy specimens, only venous involvement was seen; in 31%, both venous and arterial involvement was present. Only 8% of the positive specimens showed arterial lesions exclusively. The extent of angiitis was quantitated. Focal segmental elastic tissue destruction, partial or complete, was a common finding. No instances of aneurysm formation, endothelial erosion, or thrombosis were observed. Occlusive narrowing of small vessels was frequent. Bronchial blood vessels were not involved.

Adolescent↗
PubMed1976

Further observations on tuberculin reactions in active tuberculosis.

One hundred patients with active tuberculosis were tested for tuberculin reactivity within 24 hours of their admission to the hospital. Commercial intermediate tuberculin, Tween stabilized intermediate tuberculin and the Tine test as well as a mumps antigen were applied simultaneously. False negative reactions were obtained in 28 per cent with Tine testing and in 21 per cent with Tween stabilized as well as plain tuberculin. These nonreactors were clinically identifiable as seriously ill with manifestations primarily attributable to protein depletion as a result of their illness. This is not specifically related to the effects of tuberculosis itself, but can be demonstrated in patients suffering the same sequelae of other debilitating illness. After two weeks of protein supplementation via a high calorie, high protein, hospital diet, skin reactivity was restored in the vast majority of these nonreactors. It is concluded that the lack of tuberculin reactivity on hospital admission probably results from impaired lymphocyte function in patients suffering serious protein depletion as a result of their illness; it is not attributable to deficiencies in the tuberculin test itself.

Adult↗
PubMed1976

Markedly elevated angiotensin converting enzyme in lymph nodes containing non-necrotizing granulomas in sarcoidosis.

Sarcoidosis is a disease of unknown etiology that is characterized by the generalized formation of granulomas and is accompanied by elevation in the serum in less than half the patients of angiotensin converting enzyme, a dipeptidyl carboxypeptidase that catalyzes the conversion of the decapeptide, angiotensin I, to the pressor octapeptide, angiotensin II, and L-histidyl-L-leucine. Mean activity of angiotensin converting enzyme was elevated generally more than 10-fold in granuloma-containing lymph nodes, but not in lung in which normally it is abundant, in 19 of 20 patients with sarcoidosis. Angiotensin converting enzyme in lymph nodes from subjects with sarcoidosis was similar to the enzyme from normal lung and lymph node with respect to activity as a function of pH, inhibition of activity by EDTA and o-phenanthroline, gel filtration on Sephadex G-200, and requirement for chloride for activity, but appeared to be more heat labile. The data suggest that the granulomas in sarcoidosis may be the source of the elevated serum enzyme and that cells of the granulomas, particularly the epitheloid cells which appear by electron microscopy to have active protein biosynthesis, may be actively synthesizing the enzyme.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1976

Elevation of angiotensin-converting enzyme in granulomatous lymph nodes and serum in sarcoidosis: clinical and possible pathogenic significance.

A statistically highly significant elevation of serum ACE was found in a group of 58 patients with sarcoidosis (serum ACE was elevated in 34% of patients), as compared with normal controls and patients with tuberculosis and various other common diseases. The results suggest that serum ACE is a useful aid for the diagnosis of sarcoidosis when elevated, but that a normal value does not rule out the condition and may occur in more than one-half of monitored patients. There is a trend to diminution of serum ACE with increasing duration of disease with or without steroid therapy, perhaps correlating with the total body mass of active granulomas, as indirectly suggested in preliminary data by correlation of serum ACE with serum globulin in 16 sarcoidosis patients. It is not yet clear whether there is any significant steroid effect on serum ACE, but a significant number of patients on steroid therapy for more than 2-4 yr have elevated serum ACE values, which in some instances are extremely high. There was a 12-fold elevation in ACE to specific activities generally exceeding those of normal lung in granulomatous lymph nodes of 14 patients with sarcoidosis, suggesting that sarcoid granulomas may be actively synthesizing ACE and resulting in elevation of serum ACE. Extensively fibrotic sarcoid lymph nodes had normal or slightly elevated ACE, suggesting that obliteration of granulomas in sarcoid lymph nodes diminishes their ACE content and that this obliteration may be related to the tendency to diminution of serum ACE with time. ACE was not elevated in one tuberculous lymph node or in experimental granulomas, suggesting that elevation of ACE may have some specificity for the granuloma of sarcoidosis rather than being a characteristic of all granulomas. The catalytic and physical properties of ACE in serum and lymph nodes in sarcoidosis were generally similar to normal ACE with respect to pH activity, modulators, polyacrylamide-gel electrophoresis, and Sephadex G-200 gel filtration. However, sarcoid lymph node ACE appeared to be more heat labile than normal lung or lymph node ACE, suggesting the possibility that an abnormal ACE may be present in sarcoidosis. If an abnormal enzyme is indeed present, it might be coded for by a host gene that is not normally expressed or a nonhost gene or it might be a normal ACE that has been altered. No ACE activity was found in circulating white blood cells in sarcoidosis or in control subjects, suggesting that circulating white blood cells may not contain the epithelioid cell precursor or that ACE synthesis (or less likely, uptake) may be turned on at a later stage in the transformation. Lysozyme activity was also elevated in sarcoid lymph nodes. Serum ACE and serum lysozyme were significantly positively correlated in 16 sarcoidosis patients, suggesting a relationship between the two...

Granuloma↗