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Biomedical subjects

P Ferguson

Publications and source records attributed to P Ferguson.

At least 37 records · Page 2Linked to original sources

Airway levels of mast cell-derived mediators in exercise-induced asthma.

In order to assess the role of mast cell-derived mediators in the pathogenesis of exercise-induced asthma (EIA), we completed pre- and postexercise bronchoalveolar lavage (BAL) in seven atopic subjects with EIA. The study subjects were defined as having EIA if they exhibited a greater than 15% decrease in FEV1 after completing 6 min of treadmill exercise. There were no significant differences between mean preexercise and mean postexercise mast cell-derived BAL histamine (186 +/- 67 versus 148 +/- 36 pg/ml), tryptase (4.5 +/- 2.0 versus 2.8 +/- 2.0 ng/ml), prostaglandin D2 (26 +/- 11 versus 32 +/- 25 pg/ml), or leukotriene C4 (less than 100 versus less than 100 pg/ml). In addition, mast cells present in BAL fluid after exercise contained similar amounts of cellular histamine compared with BAL mast cells obtained before exercise (preexercise BAL cellular histamine, 26.6 +/- 12.3 ng/10(6) BAL cells; postexercise BAL cellular histamine, 22.7 +/- 9.1 ng/10(6) BAL cells), indicating that depletion of preformed mast cell mediators are unlikely to account for the refractory period in EIA. This study suggests that the cellular pathogenesis of EIA (mast cell-independent) differs from current theories of the pathogenesis of extrinsic allergen-induced asthma (mast cell-dependent).

Adolescent↗

Long-term prognosis after repair of double-chamber right ventricle with ventricular septal defect.

To determine long-term postoperative results in patients with double-chamber right ventricle and ventricular septal defect, 20 patients who had survived complete repair between 1959 and 1966 were recalled and studied. An interview, physical examination, electrocardiogram and chest x-ray were performed in all 20 patients, a treadmill exercise test in 16, 24-hour Holter monitor recording in 7 and postoperative cardiac catheterization in 8. Mean age at repair was 14 years and at follow-up evaluation 33 years. There were no late deaths. At a mean follow-up of 19 years, 17 patients were in New York Heart Association functional class I, 1 patient was in class II and 2 patients were in class III. Reoperation was performed in 2 patients (10%), and at present only 1 patient (5%) is considered to have hemodynamically significant cardiac compromise. Aortic regurgitation, not present in any patient preoperatively, developed in 5 patients (25%). Mild residual right ventricular outflow obstruction was present in 2 (10%) and the murmur of a hemodynamically insignificant residual ventricular septal defect or tricuspid regurgitation was present in 5 patients (25%). One patient (5%) had cardiomegaly (cardiothoracic ratio greater than 0.55). The frequency of infective endocarditis in the postoperative follow-up period was 1 per 388 patient-years. Thus, 20 years after repair of double-chamber right ventricle, mild residua and sequelae are common, but serious cardiac compromise is infrequent.

Adolescent↗

Long-term prognosis (15 to 26 years) after repair of tetralogy of Fallot: I. Survival and symptomatic status.

One hundred eighty-two patients with tetralogy of Fallot repaired before or during 1967 were studied by interview, physical examination, and noninvasive testing. Twenty were excluded from the final analysis because review of cineangiograms and operative reports disclosed that they had had double-chambered right ventricle rather than tetralogy of Fallot. On follow-up ranging from 15 to 26 years (mean, 20.2 years), there were 86 patients in New York Heart Association Functional Class I, 53 in Class II, 5 in Class III, and none in Class IV. There were 9 late deaths. Functional classification was not ascertained in the remaining 9 patients. Cumulative survival at 25 years postoperatively was 94.4%. There was no significant relationship between survival and year of operation, age at operation, sex, or presence of a prior shunt. The 9 late deaths occurred between 6 and 23 years after operation and were due to late-onset complete heart block in 2 patients, congestive failure in 4, suicide in 1, accident in 1, and an unknown cause in 1. We conclude that long-term survival after repair of tetralogy of Fallot is excellent and not influenced by prior shunt.

Adolescent↗

Increased sulphation level and altered composition of glycosaminoglycans synthesized by cultured smooth muscle cells in the presence of beta-D-xylosides.

Cultured rat and bovine smooth muscle cells incorporated more 35SO4 into macromolecular glycosaminoglycans in the presence of beta-D-xylosides than in their absence. More than 90% of the xyloside-initiated glycosaminoglycans were secreted rapidly into the culture medium and were more highly sulphated than glycosaminoglycans polymerized on core protein. The increased extents of sulphation were associated with increased synthesis of dermatan sulphate and a decrease in that of nitrous acid-sensitive glycosaminoglycans.

Animals↗

Effects of age, gender, and cigarette smoking on human immunoregulatory T-cell subsets: establishment of normal ranges and comparison with patients with colorectal cancer and multiple sclerosis.

Normal ranges for peripheral circulating mature functional T cells (OKT3+), T helper-inducer cells (OKT4+), and T cytotoxic-suppressor cells (OKT8+) were determined in 161 normal male and female volunteers. Children between 5 and 15 years of age showed higher circulating OKT3+ cell numbers than adults, and in male children the circulating OKT4+ cell number was also higher. In adults, females demonstrated higher circulating OKT4+ cell numbers than males, and smokers demonstrated higher circulating numbers of both OKT3+ and OKT4+ cells than nonsmokers. There was a significant interaction between gender and smoking, with female smokers exhibiting the highest circulating OKT3+ cell numbers. Two groups of patients entering longitudinal T-cell subset monitoring studies were compared to their appropriate normal control groups. It was found that 48% of patients with colorectal cancer were T-cell (OKT3+) lymphopenic at presentation, and that 62% had a low OKT4/OKT8 ratio. Colorectal surgery tended to correct this T-cell lymphopenia. However, only transient rises in low OKT4/OKT8 ratios were observed after surgery. Of 11 patients with multiple sclerosis in a trial of transfer factor therapy, 7 were found to have high OKT4/OKT8 ratios prior to treatment; these ratios have persisted to date during treatment.

Adolescent↗

Carcinoma-associated cytostructural antigenic alterations: detection by lectin binding.

Tumor cell membrane glycoproteins may be involved in the induction of tumor immunity or in the escape of tumors from immunologic defense mechanisms. Previous investigations have suggested a role for blood group antigens and their precursors, in the generation of the immune response to neoplasia. In this study, 44 benign and malignant breast lesions were examined for the presence of a carbohydrate precursor antigen (T-antigen) of the human blood group system MN. T-antigen was demonstrated using an immunohistochemical technique to detect tissue binding of a plant lectin (PNA) with specificity for T-antigen. Of the 22 benign breast lesions examined, 19 showed T-antigen present along the luminal cytoplasmic membrane and occasionally on intraluminal secretions. T-antigen, as demonstrated by lectin binding, was confined to this region in all benign lesions except one, which also showed cytoplasmic positivity. Malignant breast lesions showed a pattern of T-antigen expression markedly different from that of benign breast tissues. Of 22 breast carcinomas, 17 showed diffuse cytoplasmic T-antigen. Five carcinomas showed no evidence of T-antigen by this technique. These malignancies tended to be the most poorly differentiated when judged by histologic criteria. A possible role for T-antigen in the modulation of the immune response to breast carcinoma is suggested.

Antigens, Neoplasm↗

Carcinoma of the lung: results of treatment over ten years.

Mediastinal lymph node dissection in conjunction with pulmonary resection was performed on 437 patients with bronchogenic carcinoma at the University of Michigan Medical Center from 1959 to 1969. The absolute five- and ten-year survival rates for patients undergoing curative resection were 36.2 and 14.4%, respectively. The five-year survival of those without nodal metastases was 49.3%, and it was 31.1% in patients with hilar metastases only. The five-year survival of patients with mediastinal metastases who received radiation therapy was 23.1%. Of the 193 patients with squamous cell carcinoma, 43% lived five years free from disease. The five-year survival of patients undergoing resection who had no hilar lymph node metastases was 53%, and it was 47.5% in those with hilar metastases only. The five-year survival in patients with mediastinal metastases who received postoperative irradiation was 34.4%.

Adenocarcinoma↗

Major pulmonary resection for bronchogenic carcinoma in the elderly.

The results of major pulmonary resection in 58 patients greater than 70 years of age were reviewed. The histological distribution and extent of nodal metastases in this age group are the same as in younger patients. The absolute five-year survival rate for the 55 patients undergoing curative resection was 30% (17 patients). It was 36% (11 patients) for those patients with squamous cell carcinoma and 22% (5 patients) for those with adenocarcinoma. The operative mortality was only 14% (8 patients). Of the 49 patients treated by lobectomy, 17 lived five years or more free of disease, whereas none of the 6 patients treated by pneumonectomy survived five years. The five-year survival rate of 30% in this series of elderly patients treated by major pulmonary resection makes resections in such patients with bronchogenic carcinoma worthwhile.

Adenocarcinoma↗

Review of criteria used to measure library effectiveness.

This article reports the results of a survey of literature on measures of library effectiveness. This survey led to the formulation of six criterion concepts (accessibility, cost, user satisfaction, response time, cost/benefit ratio, and use). The advantages and disadvantages of each method of measurement are discussed. Several points which became clear during the analysis are discussed. First, there is a relative lack of concern with the rationale behind the evaluation process, although the results invariably lead to a confused interpretation when there is no clear understanding of the purpose of an evaluation. Second, the total library system is rarely considered; instead, each evaluation criterion is taken in isolation rather than as part of the whole. Third, the library's preservation function has not been considered at all.

Consumer Behavior↗