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C Clelland

Publications and source records attributed to C Clelland.

24 records · Page 2Linked to original sources
PubMed1990

Lung function associated with histologically diagnosed acute lung rejection and pulmonary infection in heart-lung transplant patients.

A group of 34 heart-lung transplant patients were studied with serial pulmonary function measurements, chest radiographs, and transbronchial biopsies from the time of surgery. These investigations were carried out routinely at 3 and 6 months and then annually after transplantation as well as on clinical suspicion of acute lung rejection or infection. A total of 61 transbronchial biopsies and concurrent lung function and chest radiographs were obtained. Of the biopsies, 30 (49.2%) showed histologic evidence of lung rejection, 12 (19.7%) demonstrated various opportunistic infections, and 19 (31.1%) were normal. Compared to during episodes of normal biopsies, FEV1 decreased significantly with lung rejection (p less than 0.001) and with infection (p less than 0.01). Vital capacity (VC) and DLCO also fell with these acute lung complications. Using histologic diagnosis as a standard, lung function testing had a sensitivity of 86% in detecting lung rejection in the first 3 months postoperation and 75% in the subsequent period. Its sensitivity for detecting lung infection was 75%. Although not distinguishing between these two complications, lung function had a specificity of 84% for detecting occurrence of an acute lung complication. Chest radiographs, although of similar sensitivity in the first 3 months postsurgery, had a sensitivity of only 19% for rejection in subsequent months and 58% for infection. Its specificity was 100%. Lung function testing changes in a predictable fashion with lung rejection and infection, offers an improvement over chest radiographs, and provides a quantitative measurement to aid the decision of when to undertake transbronchial lung biopsy.

Biopsy↗
PubMed1990

Acetylcholine and adenosine diphosphate cause endothelium-dependent relaxation of isolated human pulmonary arteries.

Endothelium-dependent vasorelaxation mediated by endothelium-derived relaxing factors (EDRF) has been extensively studied in animals but only limited studies in man are available. Demonstration of EDRF-mediated dilatation of human vessels is fundamental for understanding the mechanisms of vascular diseases in man. We have investigated endothelium-dependent relaxation of isolated human pulmonary arteries. Vascular segments, taken from uninvolved regions of resected lung from eight patients undergoing lobectomy for lung carcinoma, were cut into rings. In rings precontracted with phenylephrine, both acetylcholine (ACh) and adenosine diphosphate (ADP) induced dose-dependent relaxation in the presence of endothelium but not when the endothelium had been carefully removed. The rings without endothelium relaxed completely with sodium nitroprusside, a vasodilator agent acting directly on vascular smooth muscle. Pre-incubation with indomethacin, a cyclo-oxygenase inhibitor which blocks production of prostacyclin, did not alter the vasorelaxant responses to ACh and ADP, suggesting that one (or several) non-prostanoid EDRF(s) are responsible for the endothelium-dependent relaxation of isolated human pulmonary arteries.

Acetylcholine↗
PubMedDate not supplied

Histologic prognostic indicators for the lung allografts of heart-lung transplants.

The histologic changes in transbronchial lung biopsy specimens of heart-lung transplant patients were graded during episodes of acute rejection and when patients were well. Infection was strictly excluded from all episodes studied. Grade of severity of rejection was determined by the magnitude and extent of the inflammatory infiltrate. Biopsy specimens, obtained 1 year after the initial biopsies, were examined for histologic evidence of airway submucosal fibrosis, and each patient's clinical status at this time was recorded. The biopsy material from 22 long-term survivors was studied. On 16 occasions the specimens showed no evidence of rejection (grade 0). Twelve of these sets of specimens were from clinically well patients, and four were from the patients who had clinical evidence of rejection. The other six sets of specimens, from clinically well patients, showed evidence of rejection: three grade 1 and three grade 2. One year later, the clinically well patients had normal biopsy histology without fibrosis and normal lung function. Bronchiolitis obliterans had not developed in any patient. There were 27 episodes of rejection in the 22 patients, of which 23 were confirmed histologically. Eleven sets of specimens had grade 1 acute rejection, eight grade 2, and four grade 3. Three of these patients died, and bronchiolitis obliterans was confirmed at necropsy. Lung fibrosis was more common in specimens taken after 1 year, and lung function was depressed in these patients. The histologic grading of transbronchial lung biopsy material, although still in the early stages of development, provides some predictive value to the long-term outcome of the lung transplant patient, in development of both bronchiolitis obliterans and lesser fibrotic changes.

Biopsy↗