Search PubMed⌕ Search

Biomedical subjects

R Leigh

Publications and source records attributed to R Leigh.

16 recordsLinked to original sources
PubMed2000

Induced sputum: validity of fluid-phase IL-5 measurement.

BACKGROUND: IL-5 measurement in the fluid phase of induced sputum is considered to be important in the assessment of asthma, but the validity of these measurements is uncertain. OBJECTIVE: We investigated the validity of sputum IL-5 measurements through a series of spiking experiments and examined the effect of dithiothreitol (DTT) on these measurements. METHODS: Induced sputum from 26 asthmatic subjects was spiked with IL-5 and processed, and the percentage of recovery was measured by means of immunoassay. In 6 of the 26 samples the effect of adding albumin to the processing fluids was studied. In 3 separate samples radiolabeled IL-5 was added, and the recovery measured by means of gamma counting and immunoassay were compared. In addition, the effect of DTT on the immunoassay was examined. RESULTS: The mean +/- SD recovery of spiked IL-5 was 26.1% +/- 14.6% measured by means of immunoassay; adding albumin increased the recovery to 47.7% +/- 8.0% (P <.001). The mean recovery measured by means of gamma counting was 84.8% +/- 5.7% (P <.001); adding albumin had no effect on recovery. DTT had no significant effect on IL-5 measurement. CONCLUSION: The validity of IL-5 measurement by means of current methods is poor. The discrepancy in recovery as measured by gamma counting compared with immunoassay suggests that there is a problem with the recognition of IL-5 epitopes by immunoassay in induced sputum. This cannot be attributed to DTT but may be due to other interfering substances present in sputum, such as sputum proteases, soluble receptors, or autoantibodies.

Dithiothreitol↗
PubMed2000

Induced sputum examination: diagnosis of pulmonary involvement in Fabry's disease.

Fabry's disease is a rare inherited metabolic disorder caused by a deficiency in the enzyme alpha-galactosidase A. It can affect almost every organ, including the lungs. Confirmation of lung involvement has depended on invasive bronchial biopsy specimens or brushings to confirm the presence of typical lamellar inclusion bodies within bronchial epithelial cells. We report a patient with known Fabry's disease in whom these inclusion bodies were identified by examination of induced sputum.

Adult↗
PubMed2000

Induced sputum cell counts in healthy adults.

Induced sputum cell counts provide a relatively noninvasive method to evaluate the presence, type, and degree of inflammation in the airways of the lungs. Their interpretation requires a knowledge of normal values from a healthy population. The objective was to examine the total and differential cell counts in induced sputum from a sample of healthy adults. A total of 118 healthy nonsmoking adults were studied. None had asthma or airflow obstruction (negative history, FEV(1) >/= 80% predicted, ratio of FEV(1) to vital capacity [FEV(1)/VC] >/= 80%, methacholine PC(20) >/= 16 mg/ml). Forty-six were atopic. Sputum induction produced an adequate sample in 96 subjects [53 males, mean age (range) 36 (18 to 60) yr]. The expectorate was processed within 2 h; sputum was selected, treated with dithiothreitol, filtered, and examined in a hemocytometer for total cell count and viability and on Wright-stained cytospins for a differential cell count. The mean, median (90th percentile) total cell count was 4.1, 2.4 (9.7) x 10(6) cells/g and cell viability was 69.6, 72.0 (89.7)%. The proportions of eosinophils were 0.4, 0.0 (1.1)%, neutrophils 37.5, 36.7 (64.0)%, macrophages 58.8, 60.8 (86.1)%, lymphocytes 1.0, 0.5 (2.6)%, metachromatic cells 0.0, 0.0 (0.04)%, and bronchial epithelial cells 1.6, 0.3 (4.4)%, respectively. Female gender and atopy were associated with a significant elevation of eosinophils; mean difference between male/female was 0.3% (p = 0.043) and between atopic/nonatopic 0.4% (p = 0.024). This study has identified reference values for total and differential cell counts in induced sputum of healthy adults.

Adolescent↗
PubMed1999

Induced sputum, eosinophilic bronchitis, and chronic obstructive pulmonary disease.

The application of sputum induction and refined methods of sputum examination has provided the opportunity to examine cell and molecular markers of airway inflammation in asthma, COPD, and other airway diseases. The measurements are relatively noninvasive and can be applied safely, with care, even in more severe exacerbations of asthma and severe COPD. Induced sputum examination can be applied at random and repeatedly and gives results that are reproducible, valid, and responsive to changes in treatment. An eosinophilic bronchitis, defined as sputum eosinophilia, is typical of asthma but can also occur in patients with a chronic cough without asthma, and in some patients with COPD in whom the classic inflammatory response is neutrophilic without eosinophilia. When eosinophilia occurs in COPD, it has been considered to be the result of cigarette smoking but it may be due to other causes. The clinical importance of eosinophilic bronchitis is that it responds to treatment with corticosteroid. In contrast, there is increasing evidence that an absence of sputum eosinophilia is associated with steroid resistance. Hargreave FE, Leigh R. Induced sputum, eosinophilic bronchitis, and chronic obstructive pulmonary disease.

Asthma↗
PubMed1998

Perversion.

Explore the source record for details and available documents.

Humans↗
PubMed1984

Morphometric analysis of small intestinal mucosa. I. Methodology, epithelial volume compartments and enumeration of inter-epithelial space lymphocytes.

Morphometric techniques for quantitating cytologic and volumetric changes in small intestinal mucosae are described: measurements were controlled with respect to a constant 'test area' of muscularis mucosae, thus following valid comparisons between normal and damaged mucosae. Procedures for enumerating cell populations within mucosal volume compartments are illustrated by analyzing lymphocytes within surface epithelium. These techniques serve to distinguish (i) absolute cell counts from (ii) relative cell counts ("densities") the latter being shown to be considerably affected by changes in epithelial volume. They also permit construction of mathematical models e.g. cubes of equivalent volume, volume-density graphs, proportional volumes, which are illustrated. Use of these morphometric procedures showed that there is no major difference in epithelial lymphocyte populations between untreated coeliac disease, and control, mucosae. The data thus fail to support the widespread view that "infiltration" of coeliac disease epithelium by lymphocytes represents a local cell-mediated immune reaction to gluten.

Celiac Disease↗
PubMedDate not supplied

Occupational neutrophilic asthma.

Occupational asthma is typically associated with an eosinophilic bronchitis. The case of a 41-year-old woman who developed symptoms of asthma after occupational exposure to metal working fluids is reported. The diagnosis of asthma was confirmed by an forced expiratory volume in 1 s (FEV1) of 1.7 (59% predicted), with 11% reversibility after inhaled bronchodilator and a provocation concentration of methacholine to cause a fall in FEV1 of 20% (PC20) of 0.4 mg/mL. Induced sputum examination showed a marked neutrophilia. Over the next six months, serial sputum analyses confirmed the presence of a marked sterile neutrophilic bronchitis during periods of occupational exposure to metal working fluids, which resolved when the patient was away from work and recurred when she returned to work. The sputum findings were mirrored by corresponding changes in spirometry and PC20 methacholine. The findings indicate the occurrence of occupational asthma associated with an intense, sterile neutrophilic bronchitis after exposure to metal working fluids.

Adult↗