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Biomedical subjects

T R Collins

Publications and source records attributed to T R Collins.

At least 19 recordsLinked to original sources

Positive predictive value of cardiac fluoroscopy in asymptomatic U.S. Army aviators.

The primary aim of this study was to determine the positive predictive value (PPV) of cardiac fluoroscopy in U.S. Army aviators. Cardiac fluoroscopy is one of the non-invasive tests used to screen for coronary artery disease (CAD) in the U.S. Army Cardiovascular Screening Program. The secondary objective is to determine the positive predictive value (PPV) of the combination of the aeromedical graded exercise test (GXT) and cardiac fluoroscopy. The results of these two screening tests are used to determine the need for coronary angiography. Records of 220 male aviators (mean age--42.3) who underwent coronary angiography from 1990-95 were obtained from the Aviation Epidemiology Data Register (AEDR) at Ft. Rucker, AL. These records contained results from the screening tests (GXT, cardiac fluoroscopy, and thallium scintigraphy) and coronary angiography. Significant CAD (SCAD) was present in 47 (21%), while 83 (38%) had minimal CAD (MCAD). The PPV of cardiac fluoroscopy was 81% for all CAD (34% for SCAD). GXT and thallium scintigraphy had a PPV of 62 and 67% for all CAD (23 and 45% for SCAD), respectively. The PPV's of the screening tests were not statistically different at the 95% confidence interval level. The combination of GXT and cardiac fluoroscopy had a PPV of 64% (21% for SCAD).

Adult↗

Small cell carcinoma of urinary bladder is differentiated from urothelial carcinoma by chromogranin expression, absence of CD44 variant 6 expression, a unique pattern of cytokeratin expression, and more intense gamma-enolase expression.

AIMS: Small cell (neuroendocrine) carcinoma of the urinary bladder is clinically more aggressive than urothelial (transitional cell) carcinoma. We have investigated the immunohistochemical markers most useful in diagnosing small cell carcinoma in bladder. METHODS AND RESULTS: We evaluated the expression of chromogranin A, CD44 variant 6 (CD44v6), cytokeratin (CAM 5.2), gamma-enolase, synaptophysin, and CD45 in 46 small cell carcinomas of the bladder. Small cell and urothelial carcinoma were mixed in 21 (46%) cases. The two immunohistochemical markers with best ability to discriminate between small cell and urothelial carcinoma were chromogranin A and CD44v6. Chromogranin A had 97% specificity for small cell carcinoma, staining 65% of cases with 2+/3+ mean intensity; only one case (5%) of urothelial carcinoma was weakly (1+/3+) positive. CD44v6 was 80% specific for urothelial carcinoma, with immunoreactivity in 60% of cases, compared with 7% of small cell carcinoma cases. In cases positive for CD44v6, the mean percentage of reactive urothelial carcinoma cells was 75% (range 10-100%), greater than the 12% of cells in three cases of small cell carcinoma (P = 0.31); further, the pattern of immunoreactivity was membranous vs. focal cytoplasmic, respectively. All small cell carcinomas stained with one of the three neuroendocrine markers tested; 76% of cases were reactive for synaptophysin and 93% for gamma-enolase, with specificities of 86% and 73% in comparison to urothelial carcinoma. gamma-enolase staining of small cell carcinoma was more intense (P = 0.01) than for urothelial carcinoma. Cytokeratin CAM 5.2 stained a mean 47% of cells in small cell carcinoma, always in a punctate perinuclear pattern, and 75% in urothelial carcinoma, in a membranous pattern. CONCLUSIONS: CD44v6, chromogranin A, and possibly gamma-enolase and cytokeratin (CAM 5.2) help differentiate small cell carcinoma from urothelial carcinoma.

Adult↗

The Association of Teachers of Preventive Medicine's recommendations for postgraduate education in prevention.

The Guide to Clinical Preventive Services, prepared in 1989 by the U.S. Preventive Services Task Force, assesses the effectiveness of 169 types of preventive interventions. In 1990, the Association of Teachers of Preventive Medicine formed a panel to review the guide and recommend ways it could be used to enhance both undergraduate and postgraduate medical education. This paper outlines the panel's recommendations of the types of knowledge and attitudes on which postgraduate medical education in prevention should be built. Detailed recommendations are presented, based on the summary findings of the guide, for residency education in prevention. Implementation of these recommendations will integrate preventive services into the continuum of medical care. These recommendations are presented to achieve the goal of educating physicians to approach the total patient, putting the patient's health rather than the disease process in the forefront of primary medical care.

Education, Medical, Graduate↗

Thoracocentesis. Clinical value, complications, technical problems, and patient experience.

A prospective study of 129 consecutive thoracocentesis in 86 patients at a university medical center evaluated the clinical value, complications, and patient experience with thoracocentesis. Pleural fluid analysis in conjunction with the clinical presentation placed 78 pleural fluids into diagnostic categories: definitive 14 (18 percent), presumptive 44 (56 percent), and nondiagnostic 20 (26 percent). Fourteen of 78 (18 percent) of the nondiagnostic fluids were useful, while only six (8 percent) were not useful clinically; therefore, 92 percent of thoracocentesis provided clinically useful information. Using sequential data analysis, initial diagnostic categorizations of eight of 78 patients were upgraded from presumptive or nondiagnostic to definitive based on data available 24 hours following thoracocentesis. Thus, 70 patients were categorized based on the pleural fluid data obtained within the first 24 hours of thoracocentesis. Thirty-four objective complications occurred in 26 of 129 (20 percent) thoracocentesis. The most common complications were pneumothorax, 15 of 129 (12 percent), and cough, 12 of 129 (9 percent). Sixty-five subjective complications occurred in 56 of 123 (46 percent) thoracocentesis. Anxiety, 26 of 123 (21 percent), and site pain, 24 of 123 (20 percent), were the most common subjective complications noted. Thirty technical problems occurred in 129 (23 percent) thoracocentesis with blood contamination, 14 of 129 (11 percent), and dry tap, nine of 129 (7 percent), being the most common. We conclude that diagnostic thoracocentesis is a clinically valuable procedure if used in conjunction with the patient presentation with an understanding of its limitations for providing a specific etiologic diagnosis. When performed by physicians in training, the number of complications are substantial and the operator often underestimates the degree of patient discomfort. Awareness of the clinical value and complications of thoracocentesis should lead to improved use and safety of this procedure.

Adult↗

Supplemental Food Program: effects on health and pregnancy outcome.

To determine the effect of participation in the Special Supplemental Food Program for Women, Infants, and Children on use of health care, health-related practices, health knowledge, and pregnancy outcome, a total of 519 pregnant women were interviewed during public health department clinics in six Alabama counties. Of the sample, 341 women were participants in the WIC program and were therefore at nutritional risk; 178 were control subjects (nonparticipants) who were not at nutritional risk. There were no significant differences in pregnancy outcome between the two groups. In fact, mean birth weight was identical (7.13 lb), and mean weight gain for WIC participants was 25.8 lb, compared to 24.9 for controls. Other findings were less positive, however. Utilization patterns and health-related practices differed little between groups. There was no significant difference in the percentage of women planning to nurse. Significantly more WIC participants had discussed nursing, but significantly fewer felt they knew how to nurse. WIC is effective in overcoming nutritional risk and improving pregnancy outcome, but its educational component needs to be strengthened.

Adolescent↗

School health education in family medicine and pediatrics.

This study concerns what is thought appropriate and what is being taught residents in family practice and pediatrics. University based training programs were selected for study and 63 family practice and 125 pediatric programs were surveyed by mail. The response rate for two mailings was 76 percent for pediatric and 81 percent for family practice programs. A larger proportion of pediatric than family practice programs teach diagnosis of mental retardation; educational placement of the mentally retarded; diagnosis of communication defects; trends in special education, and placement in special education; interdisciplinary teaming; and organization of the school system. Family practice programs focus more on the health problems of the school-aged athlete and the teaching of health education. School consultation and the implementation of clinical preventive medicine into care of the school-aged child are evident areas of weakness in current programs. The family physician must become more involved with the school placement of children and be aware of the relationship between school activities and health problems seen in the office setting.

Child↗

A simple method for freeze-fracture of monolayer cultures.

A simple method is described for the freeze-fracture in situ of monolayer cultures grown on gold carriers coated with a thin layer of silicon monoxide. Preliminary observations on 3T3 mouse embryo fibroblasts indicate that this technique exposes large areas of cell membrane, making it possible to determine how areas of membrane specialization are related to the cell as a whole and to regions of cellular interaction. 3T3 cells cultured on silicon monoxide show no modification of growth properties compared to cells growing on Falcon plastic, and other cell lines also appear to grow well on this substrate.

Cell Division↗