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Biomedical subjects

J B Masterson

Publications and source records attributed to J B Masterson.

13 recordsLinked to original sources
PubMed1997

Elevated levels of matrix metalloproteinases in bronchoalveolar lavage fluid of emphysematous patients.

BACKGROUND: Matrix degradation in emphysema has long been attributed to the action of neutrophil elastase (NE). More recently a role for other proteases, particularly the matrix metalloproteinases (MMPs), in the pathogenesis of this disease has been proposed. To date, however, the presence of MMPs in the lungs of patients with emphysema has not been demonstrated. METHODS: Samples of bronchoalveolar lavage (BAL) fluid from 10 patients with emphysema and from control subjects matched for sex and current smoking status were assessed for collagenase, gelatinase, and NE activity. Pulmonary function tests and computed tomographic (CT) scans were carried out on all study subjects. RESULTS: Collagenase activity was detected in BAL fluid samples from all emphysematous patients but in only one smoking control (p < 0.001). Gelatinase B was present in six patients and in two smoking controls (p < 0.03). The concomitant presence of gelatinase B in complex with lipocalin (NGAL) in the gelatinase positive samples suggests that the neutrophil is a significant source of the gelatinase B observed. NE was detected in six of the 10 patients with emphysema and in two smoking controls (p < 0.01), indicating that collagenase was more useful in discriminating between disease and control groups than either NE or gelatinase B. No relationship was observed between any of the enzymes measured and pulmonary function or CT density score. CONCLUSIONS: This study demonstrates, for the first time, the presence of increased levels of matrix metalloproteinases in the lungs of patients with emphysema and suggests that, in BAL fluid, collagenase activity may be a better indicator of the presence of emphysema than elastase.

Adult↗
PubMed1997

Matrix metalloproteinase expression and production by alveolar macrophages in emphysema.

The aim of this study was to examine the hypothesis that alveolar macrophages represent a significant source of matrix-degrading proteinases in the emphysematous lung. Macrophages from bronchoalveolar lavage fluid of 10 patients with emphysema and 10 normal volunteers were maintained in vitro for 24 h and assessed semiquantitatively for mRNA transcript levels of the matrix metalloproteinases (MMPs) gelatinases A and B, macrophage metalloelastase (MME), and interstitial collagenase. Release of these MMPs into the culture medium and secretion of neutrophil elastaselike activity was also assessed. Elevated levels of mRNA transcripts for gelatinase B (p < 0.0005) and interstitial collagenase (p < 0.0005) were observed in macrophages from emphysematous patients. Increased collagenase (p < 0.01) and neutrophil elastaselike activities (p < 0.001) were also measured in conditioned medium from patient macrophages. With gelatinase B, complexed forms of the enzyme were secreted by patient but not by control macrophages. No difference in transcript levels of gelatinase A or MME was observed between patient and control samples, and neither enzyme was detected in macrophage-conditioned media from either group. These results directly demonstrate that alveolar macrophages from the emphysematous lung produce elevated quantities of matrix-degrading enzymes with both elastolytic and collagenolytic activities.

Adult↗
PubMed1992

Quantitative analysis of CT brain images: a statistical model incorporating partial volume and beam hardening effects.

The purpose of this study was to construct and evaluate a statistical model for the quantitative analysis of computed tomographic brain images. Data were derived from standard sections in 34 normal studies. A model representing the intracranial pure tissue and partial volume areas, with allowance for beam hardening, was developed. The average percentage error in estimation of areas, derived from phantom tests using the model, was 28.47%. We conclude that our model is not sufficiently accurate to be of clinical use, even though allowance was made for partial volume and beam hardening effects.

Adult↗
PubMed1978

Carcinoma of the pancreas occuring in a child: a case report with description of gray scale ultrasound findings.

This is a report of the gray scale ultrasound findings of pancreatic carcinoma occurring in a child. Although this tumor is rare, the preoperative diagnosis can be made if the physician is aware of this possibility. 99 mTc sulfur colloid radionuclide scan, liver spleen scan, gallium scan, and ultrasound examinations are helpful in distinguishing the site of origin of upper abdominal masses.

Child↗
PubMed1976

The role of small bowel follow-through examination in the diagnosis of coeliac disease.

A retrospective study of 105 barium follow-through examinations on 102 patients suspected of having malabsorption syndrome has been carried out to assess the usefulness of this technique in the diagnosis of coeliac disease. Comparison with histological and biochemical data has been made. Of the 34 examinations on 31 patients with a proven diagnosis of coeliac disease, 30 examinations showed both abnormal X-ray and biopsy findings, two examinations showed normal X-ray appearance but abnormal jejunal biopsy and two showed normal jejunal histology but abnormal X-ray findings. There were two cases with sensitivity, non-invasive nature, ease and cheapness of the technique, barium follow-through examination is suggested as the initial investigation in patients suspected of coeliac disease.

Barium Sulfate↗
PubMedDate not supplied

High resolution computed tomography in cystic fibrosis: correlation with pulmonary function and assessment of prognostic value.

OBJECTIVE: To assess the correlation between HRCT and pulmonary function in patients with CF. Further, to assess the prognostic value of HRCT in these patients. SUBJECTS AND METHODS: Clinical examination, chest radiographs and HRCT scans on 30 CF patients with an average age of 17 were scored using established scoring systems. The results were correlated with FEV1 and FVC both at time of CT scanning and after 30 months. Results were also correlated with the clinical progress of the patients over the follow-up period. RESULTS: HRCT, chest radiograph and clinical examination demonstrated similar correlation (p < 0.001) with FEV1 and FVC at the time of scanning. HRCT demonstrated the closest correlation with the clinical progress of the patients over the follow-up period and with follow-up pulmonary function. A maximum combined score for bronchiectasis and emphysema on HRCT seemed to indicate a poor prognosis. CONCLUSION: HRCT in CF patients correlates well with pulmonary function at time of scanning and at follow-up, and with clinical progress. There may be a role for CT in the identification of adolescent/adult patients who can be expected to need aggressive therapy in the future.

Adolescent↗
PubMedDate not supplied

The significance of fat and muscle areas in the lumbar paraspinal space: a CT study.

OBJECTIVE: The object of this study was to determine the significance of fat deposition and muscle dimensions on CT in the unoperated lumbar paraspinal space. MATERIALS AND METHODS: Fifty patients were prospectively studied. Paraspinal fat (PSF) and muscle (PSM) areas were correlated with various demographic and anatomical variables in patients with and without low back pain. The fat and muscle areas were derived from a standard CT image using a thresholding technique. RESULTS: Regression equations indicated that the total amount of PSF increases with age and subcutaneous fat area. The PSM area decreases with age. There was no correlation with the other variables examined. CONCLUSION: We conclude that PSF deposition and PSM dimensions on CT are related to patient age and the amount of subcutaneous fat. Paraspinal fat deposition is not a sign of muscle atrophy, and neither parameter is related to low back pain symptoms. Therefore, in patients who have not undergone spinal surgery, PSF and PSM areas are not of clinical or functional significance.

Adipose Tissue↗