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Biomedical subjects

R D Stevenson

Publications and source records attributed to R D Stevenson.

At least 73 records · Page 4Linked to original sources
PubMed1988

A retrospective survey of asthma management in hospital.

A retrospective survey of asthma admissions to general medical units during 1983 is described. 127 cases occurred, of whom 52 were males (44%). The average age was 45.2 years. Forty-eight per cent were receiving inhaled steroids or cromoglycate before admission and 16% regular oral steroids. Initial assessment seldom included peak flow measurement although these were made subsequently in 57%. No steroids were used in 32% of cases. No oxygen was given in 48% of cases and when used was usually at low flow rates. Apart from a reducing course of steroids, 46% of cases were discharged with no increase in pre-admission maintenance treatment and although follow-up was planned for 76% it was for an average 4.9 weeks later. This survey suggests a tendency to under-treatment and undersupervision of asthma patients admitted to acute general medical wards which may well be a cause of unnecessary morbidity.

Adolescent↗
PubMed1987

Transpulmonary angiotensin II formation in patients with chronic stable cor pulmonale.

The activity of the renin-angiotensin (RA) system and the ability of the lungs to generate angiotensin II (AII) were studied in 11 patients with stable cor pulmonale and respiratory failure caused by chronic obstructive bronchitis and emphysema. Angiotensin I concentrations (18.7 +/- 8.3 pmol/L) were normal, and transpulmonary AII formation rates (TRAIIFR) (14.2 +/- 18.1 pmol/min) were not significantly different from those recorded in nonedematous cardiac subjects (19.9 +/- 20.1 pmol/min), matched for sex, age, and diuretic therapy. The main determinant of TPAIIFR was the mixed venous AI concentration. Administration of oxygen for 30 min led to a small increase in TPAIIFR in the majority of patients. This increase could not be accounted for by changes in mixed venous AI. There was no correlation between serum angiotensin-converting enzyme levels and either the TPAIIFR or the systemic arterial AII concentrations.

Aged↗
PubMed1986

Secondary amyloidosis in association with Aspergillus lung disease.

Three patients with amyloidosis secondary to bronchiectasis are described: in two patients bronchiectasis was secondary to allergic bronchopulmonary aspergillosis and in the third, post-tuberculous bronchiectasis was complicated by asthma and allergy to Aspergillus. We suggest that chronic Aspergillus allergy may cause amyloidosis and that some cases of amyloidosis ascribed to tuberculosis in the past may in fact have been secondary to Aspergillus allergy.

Amyloidosis↗
PubMed1986

Life-threatening respiratory failure due to a previously undescribed myopathy.

The case of a young man with a previously undescribed myopathy associated with polydactyly is reported. Although both limb girdles were affected, the major effect of the disease was upon the respiratory muscles leading to his presentation with life-threatening respiratory failure. A further feature was pronounced stiffness of the vertebral column and limb girdles, similar in some respects to the 'rigid spine syndrome'. Muscle biopsy appearances were unique but showed some similarities to both nemaline myopathy and myotonic dystrophy. Ventilatory assistance at night using a rocking bed led to a marked improvement and has enabled the patient to return to full-time employment.

Adult↗
PubMed1985

High-dose cyclophosphamide and VP 16 as late dosage intensification therapy for small cell carcinoma of lung.

This study investigated the use of late dose intensification therapy (LDIT) with cyclophosphamide (180 mg/kg) and VP 16 (1 g/m2) plus autologous bone marrow rescue in 22 patients with small cell lung cancer (SCLC). These patients were selected from a group of 95 patients who received three courses of a five-drug induction regimen comprising cyclophosphamide (750-1000 mg/m2), adriamycin (40 mg/m2), VP 16 (100 mg/m2) for 3 days, methotrexate (50 mg/m2) and vincristine (2 mg) (CAVMO). There were 16 patients with limited disease, 8 of whom were in complete remission (CR) and 8 in partial remission (PR) after the induction therapy. The other 6 patients had extensive disease; 3 of these achieved CR and 3 PR after induction therapy. Of the 11 patients in PR, 5 responded to LDIT; 3 had a further PR, and 2 CR. Subsequent to LDIT radiotherapy 4000 cGy was given to the primary site in 10 of the 22 patients. Since the start of the study, 19 of the 22 patients have relapsed and died (median survival 11 months), while 3 remain alive and in remission at 11, 11, and 24 months. Comparison of the survival of patients receiving LDIT with that of an equivalent group (with respect to staging and response to induction chemotherapy) of patients who received induction chemotherapy alone showed no significant difference. In this study, LDIT following conventional induction therapy in patients with chemosensitive tumours did not improve survival.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

Vindesine and cisplatin combination chemotherapy compared with vindesine as a single agent in the management of non-small cell lung cancer: a randomized study.

One hundred and five patients with inoperable non-small cell lung cancer were included in a randomized trial comparing the activity of vindesine as a single agent with the combination of vindesine and cisplatin. All patients were previously untreated and the majority (70%) had squamous carcinoma. The overall partial response rates in 88 evaluable patients were 7% for vindesine alone and 33% for the combined regime. There were no complete responders in either arm. The median survival of patients treated with vindesine and cisplatin was 11 months, compared with 4 months in those treated with vindesine alone (P = 0.008). Patients showing a partial or complete response to vindesine and cisplatin survived a median duration of 13 months, compared with 7 months for non-responders (P = 0.03). This survival benefit associated with the combination was particularly apparent for patients with ECOG performance status 0 or 1 (median survival greater than 18 months and 13 months respectively), locoregional disease (median survival 14 months) and squamous cell histology (median survival 13 months). Myelo-suppression was greater with the combination but was not a major treatment problem. Neurotoxicity, which was frequently dose-limiting, was of similar severity in both treatment groups. The results indicate that the combination of vindesine and cisplatin is superior to vindesine alone for remission induction in non-small cell lung cancer and confers a significant survival advantage compared with vindesine alone in patients with favourable prognostic factors.

Adenocarcinoma↗
PubMed1982

Effect of corticosteroids on sputum sol-phase protease inhibitors in chronic obstructive pulmonary disease.

Corticosteroids caused a reduction in the ratio of sol-phase sputum concentration to serum concentration of albumin in 12 patients with chronic obstructive bronchitis, suggesting a reduction in protein transudation. Alpha-1-antitrypsin values followed the same pattern as those of albumin in both the control and treatment periods, confirming the similar behaviour of the two proteins. The alpha 1-antichymotrypsin ratios were on average three times higher than those of albumin in the control period, confirming the presence of local mechanisms in the lung for preferentially concentrating this protein. The sputum-to-serum ratio of alpha 1-antichymotrypsin, however, rose during steroid treatment with the result that there was a selective increase in this protease inhibitor, which may be of potential benefit to such patients.

Bronchitis↗
PubMed1982

Serum-mediated inhibition of human lymphocyte fc gamma-receptors in extrinsic and intrinsic bronchial asthma.

Sera from 48 patients with extrinsic asthma and 37 with intrinsic asthma were screened for immune complexes using the EA-rosette inhibition assay. Significant levels of EA-rosette inhibition were found in both groups when compared with normal sera. The serum inhibitory factor(s) is, however, more likely to be an anti-lymphocyte antibody of the IgM class than an immune complex as originally expected.

Adolescent↗
PubMed1979

Effects of theophylline on capillary tube leucocyte migration.

Theophylline stimulates the capillary tube migration of human peripheral blood mixed leucocytes. Minor stimulation of polymorph migration is produced directly by theophylline and dibutyryl cyclic AMP, but polymorph migration is markedly stimulated by mononuclear leucocyte culture supernatants to which theophylline has been added. These results suggest that polymorph migration is stimulated when intracellular cyclic AMP increases, and that mononuclear leucocytes produce a potential migration stimulator whose activity is enhanced by theophylline.

Bucladesine↗
PubMed1978

Wiskott-Aldrich syndrome with partial response to transfer factor.

A male infant presented with dermatitis, purpura and susceptibility to bacterial infections. The clinical diagnosis of Wiskott-Aldrich syndrome was confirmed and after full immunological assessment, treatment with transfer factor was commenced. This has resulted in a rise in the platelet count and improvement in the bleeding tendency. This improvement in the haematological aspect of the disease has, however, been accompanied by exacerbations of the cutaneous lesions.

Blood Cell Count↗
PubMed1978

Stimulation of capillary tube polymorph migration: an indirect glucocorticoid effect on microtubular function.

Polymorph migration stimulator (PMS) is a peptide factor produced by an in vitro reaction between glucocorticoids and human mononuclear phagocytes. This study was undertaken to determine the significance of the stimulatory effect of PMS on the capillary tube migration of human polymorphs. Colchicine, vinblastine and Nocodazole, all of which inhibit microtubular assembly, are shown to stimulate migration. Conversely, deuterium oxide which stabilizes microtubules inhibits migration. Increased intracellular cyclic AMP is associated with microtubular inhibition and isoprenaline, theophylline and dibutyryl cyclic AMP are also found to stimulate capillary tube migration. These results suggest that PMS acts by inhibiting the assembly of polymorph microtubules, an effect which may be mediated by cyclic AMP in the same manner as other peptide hormones.

Adenosine Monophosphate↗
PubMed1978

Effect of prednisolone on the growth of human bone marrow cells in vitro.

The addition of prednisolone to autostimulatory cultures of human bone marrow in agar results in the formation of an increased number of granulocytic aggregates. The effect is dependent on the concentration of cultured cells and does not occur at low cell concentration. The increase in aggregate numbers is maximal early in the culture and occurs at steroid concentrations which are comparable with pharmacological levels. Prednisolone directly inhibits the responsiveness of granulocytic precursors to colony-stimulating activity (CSA) and it is suggested that the stimulatory effect is indirect and may be caused by a steroid action on mediator production. These findings may be relevant to the polymorphonuclear leucocytosis induced by glucocorticoids.

Bone Marrow↗
PubMed1977

Mechanism of anti-inflammatory action of glucocorticosteroids.

Glucocorticosteroids react with blood monocytes and tissue macrophages to produce a peptide factor which stimulates the random migration of polymorphs in vitro in the capillary-tube migration system. An identical effect on polymorph migration is produced by colchicine and vinblastine, drugs which inhibit the assembly of the cytoplasmic microtubules on which the functional activity of polymorphs depends. Pharmacological agents which inhibit microtubular assembly indirectly by increasing intracellular cyclic adenosine monophosphate (A.M.P.), also stimulate polymorph migration in vitro. These observations suggest that the anti-inflammatory activity of glucocorticosteroid drugs is mediated by a peptide hormone which inhibits polymorph microtubular assembly. Many peptide hormones are believed to act by increasing the concentration of cyclic A.M.P. within target cells and this mechanism is probably also responsible for the inhibitory effect of steroids on phagocytic cells.

Adenylyl Cyclases↗
PubMed1976

Immunological studies in pre-eclamptic toxaemia.

Although five patients with severe pre-eclamptic toxaemia (PET) had increased anticomplementary activity in their serum, there was no evidence of complement activation in the plasma of four of the five patients. These results are not implicated in the pathogenesis of PET. No significant correlation was found between anticomplementary activity and pregnancy-associated alpha2-glycoprotein.

Antigen-Antibody Complex↗