Biomedical subjects

M S Tockman

Publications and source records attributed to M S Tockman.

77 records · Page 5Linked to original sources

PubMedDate not supplied

Efficacy of two sputum collection techniques in patients with air flow obstruction.

OBJECTIVE: To compare the efficacy of two sputum collection techniques in patients with chronic obstructive pulmonary disease (COPD) in order to diagnose dysplasia or neoplasia. STUDY DESIGN: This was a crossover study design comparing induced sputum with sputum collected at home. One hundred seven patients with COPD were enrolled. Fifty-six were randomized to collect induced sputum first followed by sputum collection at home. Fifty-one randomly assigned patients collected the sputum in reverse order. RESULTS: The second sputum collection technique for both random assignments gave the greatest yield of adequate sputum. There was no significant difference in efficacy between the collection of the two sputum collection techniques in the presence of the learning (period) effect. CONCLUSION: Sputum collection is equally efficacious by the induced method and the home collection method. A learning effect was responsible for the increased yield of sputum abnormalities in the second collection session. Sputum collection at home may facilitate the amount of dysplasic and neoplastic bronchial epithelial changes in heavy smokers with COPD.

Cross-Over Studies↗

PubMedDate not supplied

Advances in sputum analysis for screening and early detection of lung cancer.

BACKGROUND: Screening for lung cancer using currently available techniques is not effective in reducing mortality from the disease. METHODS: Archived sputum specimens and clinical data linking specimens to lung cancer outcomes from prior screening programs have been reexamined to evaluate altered gene expressing, including specific oncogene activation and tumor suppressor gene deletion, as well as genomic instability and abnormal methylation. RESULTS: Several of these tests allow determination of a molecular diagnosis of cancer years before clinical presentation. CONCLUSIONS: These sputum tests provide an impetus to reconsider screening for lung cancer. Prospective trials are required to confirm test performance characteristics, and management and intervention strategies must be developed that are appropriate to the stage at which lung cancer is diagnosed.

Biomarkers, Tumor↗

PubMedDate not supplied

Loss of heterogeneous ribonucleoprotein A(2)/B(1) expression in thyroid neoplasms.

OBJECTIVE: To determine whether a difference exists in the immunohistochemical expression of heterogeneous ribonucleoprotein (hnRNP) A(2)/B(1) between benign and malignant thyroid lesions and to assess whether a gradient of expression could be found in normal thyroid, adenomas, and thyroid malignant tumors. METHODS: Formalin-fixed, paraffin-embedded archival tissues from 32 cases (8 nodular goiters, 8 follicular adenomas, 8 follicular carcinomas, and 8 papillary carcinomas) were immunostained with monoclonal antibody 703D4, directed against hnRNP A(2)/B(1), applied at a concentration of 10 microg/mL. The streptavidin-biotin peroxidase method was used to label bound monoclonal antibody. Positivity was independently scored by two pathologists, who used a three-tiered scale. RESULTS: The benign thyroid tissues, including the hyperplastic and adenomatous lesions, demonstrated 3+ granular cytoplasmic staining for hnRNP A(2)/B(1), except in two cases (one nodular goiter and one follicular adenoma) in which 2+ staining intensity was noted. In contrast, the papillary and follicular carcinomas failed to stain with the antibody, except in two cases that showed weak (1+) staining. CONCLUSION: hnRNP A(2)/B(1) immunostaining appears to distinguish benign from malignant thyroid lesions. Loss of hnRNP A(2)/B(1) expression seems to be a characteristic feature of thyroid malignant lesions.

Adenocarcinoma, Follicular↗

PubMedDate not supplied

Safe separation of sputum cells from mucoid glycoprotein.

OBJECTIVE: To compare the safety and efficacy of homogenizing sputum with deoxyribonuclease I (DNAse I), dithiothreitol (DTT), N-acetyl-L-cysteine, sodium EDTA and trypsin against standard mechanical blending to provide mucus-free, single-cell suspensions for quantitative analysis. STUDY DESIGN: Clinical sputum specimens or cultured human bronchogenic carcinoma cells were preserved in 2% polyethylene glycol/50% ethanol, divided into aliquots, counted and stained (Papanicolaou and avidin-biotin complex immunostained) at baseline. Cells of each aliquot were separated from mucus by the standard physical blending method or by chemical or enzymatic mucus liquefaction. After staining, washing and resuspending in the original volume of polyethylene glycol/ethanol mixture, aliquots were again counted and stained. RESULTS: Cell counts, Papanicolaou staining and immunostaining showed that homogenization of induced, preserved sputum with 0.5 mM DTT is safe and provides mucus-free monolayers for immunocytochemistry and single-cell suspensions for flow cytometry. Mucolysis with 0.5 mM DTT resulted in a significant (16%) increase in cells available. In contrast, mechanical blending resulted in up to a 24% reduction in specimen cellularity. CONCLUSION: Homogenization with low-concentration DTT will probably facilitate the exploration of sputum for protein and gene markers of carcino genesis.

Bronchial Neoplasms↗

PubMedDate not supplied

Effects of smoking and occupational exposures on pulmonary function impairment in Italian shipyard workers.

We examined the association of job title and duration of employment with the smoking-adjusted prevalences of chronic bronchitis, obstruction, restriction, and mixed pulmonary function impairment in 657 white male shipyard workers aged 20 to 60 years. Logistic regression was used to compute odds ratios (OR) and confidence intervals (CI) for risk of chronic bronchitis and pulmonary function impairment. Compared to employment for less than 20 years, employment for more than 20 years was independently associated with chronic bronchitis (OR = 2.0; 95% CI: 1.2-3.5), restriction (OR = 2.6; CI: 1.4-4.6), and mixed impairment (OR = 2.5; 95% CI: 1.1-5.5). Compared to metal-workers, which was the lowest exposure job category, four job categories were independently associated with restriction: gas welders (OR = 3.6; 95% CI: 1.5-8.9), arc welders (OR = 4.1; 95% CI: 1.5-11.4), masons (OR = 6.2; 95% CI: 1.0-39.0), and insulators (OR = 8.0; 95% CI: 1.8-35.2). These results suggest that exposure to pulmonary toxic agents in the shipyard environment can lead to both parenchymal inflammation (restriction) and airways inflammation (obstruction).

Adult↗