PubMed HealthSearch

Biomedical subjects

M Casey

Publications and source records attributed to M Casey.

At least 19 recordsLinked to original sources

The in-training examination in internal medicine.

OBJECTIVE: The In-Training Examination in Internal Medicine (ITE-IM) has been offered to internal medicine trainees annually since 1988 as an instrument for self-assessment. This report outlines the manner in which the test is prepared, reviews the results of annual examinations, and analyzes trends during the past 6 years. DESIGN: Results of each examination were reviewed with regard to the demographic characteristics of persons taking the test, their previous medical training, and their present program affiliations. RESULTS: Then number of residents participating in the ITE-IM has increased steadily over the past 6 years. In 1993, more than 12,000 residents from more than 90% of internal medicine training programs in the United States participated in the examination; the percentage of international medical school graduates taking the examination increased from 27% in 1988 to 47% in 1993. Statistical analyses of each examination have shown it to be reliable, internally consistent, and discriminating. Over the past 6 years, graduates of U.S. medical schools have scored consistently higher than those of international medical schools and schools of osteopathic medicine on all annual examinations. However, in 1993, for residents at all levels of training, the differences in scores between graduates of U.S. medical schools and graduates of international medical schools narrowed substantially. From 1988 to 1993, there has been a trend toward lower scores by every cohort on each subsequent examination. The decreases in scores are most pronounced for graduates of U.S. medical school and those of schools of osteopathic medicine. The lower scores may be caused by either an increased level of difficulty in the examination or decreased knowledge among examinees. CONCLUSIONS: The ITE-IM is a useful instrument to assess the knowledge base of residents and program directors with a reliable evaluation of themselves and their programs in comparison to their national peer groups. It also provides objective data to monitor trends over time in residents' scores and relates them to the changing demographic characteristics of trainees and to innovations in the clinical curricula of internal medicine training programs.

Clinical Competence

Phosphorylation of the Drosophila adherens junction protein Armadillo: roles for wingless signal and zeste-white 3 kinase.

The Drosophila segment polarity gene product Armadillo provides a link between two seemingly separate processes, regulation of segmental pattern by the Wingless intercellular signal and the function of cell-cell adherens junctions. armadillo was originally identified because of its segment polarity phenotype but subsequently was found to be the homolog of the vertebrate adherens junction protein beta-catenin. We examined the nature of the post-translational modification of Armadillo and its possible role in regulating Armadillo function. Armadillo is a phosphoprotein. Its level of phosphorylation varies both during embryonic development and from tissue to tissue. Phosphorylation occurs on both serine or threonine and tyrosine residues. Finally, Wingless signal negatively regulates Armadillo phosphorylation, while the segment polarity gene product Zeste-white 3, a serine/threonine protein kinase, promotes Armadillo phosphorylation. We discuss the implications of these results for regulation of Wingless/Wnt-1 signaling and adherens junction function.

Amino Acid Sequence

wingless signal and Zeste-white 3 kinase trigger opposing changes in the intracellular distribution of Armadillo.

wingless/wnt-1 signaling directs cell fate during development. Genetic analysis in Drosophila identified genes that may encode components of the wingless signal transduction system. Drosophila Armadillo, homolog of vertebrate beta-catenin, is required for wingless signaling. Unlike armadillo RNA, Armadillo protein accumulates non-uniformly in different cells of each embryonic segment. We found that cells alter their intracellular distribution of Armadillo in response to Wingless signal, accumulating increased levels of cytoplasmic Armadillo relative to those of membrane-associated protein. Levels of cytoplasmic Armadillo are also regulated by Zeste-White 3 kinase. Analysis of double mutants demonstrates that Armadillo's role in wingless signaling is direct, and that Armadillo functions downstream of both wingless and zeste-white 3. We present a model for the role of Armadillo stripes in transduction of wingless signal.

Animals

Technical note: room shielding requirements in diagnostic radiology.

New regulations propose a more stringent limit to the radiation exposure of workers and members of the public. The shielding in X-ray areas will have to be reassessed to take account of these new limits. This technical note identifies a computerized technique for evaluating shielding requirements which yields results that are significantly more cost effective than those determined by traditional methods.

Facility Design and Construction

Health assessment and the nursing process: a means to an end?

The content and process of teaching health assessment coupled with the nursing process gathers momentum because it is consistent with health policy based on the principles of economic rationalism, and it covertly perpetuates positivist medical discourse while overtly postulating the emancipatory nature of adopting such practices.

Holistic Health

Intestinal bile acid malabsorption in cystic fibrosis.

This study aimed at examining the mechanisms participating in excessive faecal bile acid loss in cystic fibrosis. The study was designed to define the relation between faecal fat and faecal bile acid loss in patients with and without cystic fibrosis related liver disease; to assess terminal ileal bile acid absorption by a seven day whole body retention of selenium labelled homotaurocholic acid (SeHCAT); and to determine if small intestinal bacterial overgrowth contributes to faecal bile acid loss. The study population comprised 40 patients (27 men; median age 18 years) with cystic fibrosis (n = 8) and without (n = 32) liver disease and eight control subjects. Faecal bile acid excretion was significantly higher in cystic fibrosis patients without liver disease compared with control subjects (mean (SEM) 21.5 (2.4) and 7.3 (1.2) micromoles/kg/24 hours respectively; p < 0.01) and patients with liver disease (7.9 (1.3) micromoles/kg/24 hours; p < 0.01). No correlation was found between faecal fat (g fat/24 hours) and faecal bile acid (micromoles 24 hours) excretion. Eight (33%) of cystic fibrosis patients had seven day SeHCAT retention < 10% (normal retention > 20%). SeHCAT retention in cystic fibrosis patients with liver disease was comparable with control subjects (30.0 (SEM) 8.3% v 36.8 (5.9)%; p = NS) while SeHCAT retention in cystic fibrosis patients who did not have liver disease was significantly reduced (19.9 (3.8); p < 0.05). Although evidence of small bowel bacterial overgrowth was present in 40% of patients no relation was found between breath hydrogen excretion, faecal fat, and faecal bile acid loss. The results are consistent with the presence of an abnormality in terminal ideal function in patients with cystic fibrosis who do not have liver disease and that a defect in the ileal absorption of bile acids may be a contributory factor to excessive faecal bile acid loss. Faecal bile acid loss in cystic fibrosis is unrelated to the presence of intraluminal fat or intestinal bacterial overgrowth.

Adolescent

Biliary complications of cystic fibrosis.

One hundred and four adult patients with cystic fibrosis were evaluated for the presence of liver disease as defined by abnormal liver function tests of six months' duration, histological evidence of fibrosis or cirrhosis, or the presence of portal hypertension, or both. Twenty patients fulfilled these criteria and were evaluated further for the presence of biliary tract abnormalities with biliary scintigraphy using 99Tc diisopropylphenyl-carboxymethyl iminodiacetic acid (DISIDA) and endoscopic retrograde cholangiography. Clearance of 99Tc DISIDA from the liver and biliary tree was diminished at 45 (E45) and 60 (E60) minutes in the patients with liver disease compared with those without liver disease; E45 = 37.8% and 65.8%, p less than 0.01; E60 = 48.2% and 77.5%, p less than 0.01 respectively. Serial analogue images of the extrahepatic biliary tree were consistent with common bile duct obstruction with retention of DISIDA and tapering of the common bile duct in seven of 18 patients with and two of 10 patients without liver disease. Endoscopic retrograde cholangiography showed changes consistent with sclerosing cholangitis, with beading and stricturing of the intrahepatic ducts in 12 of the 14 patients. In all 14 patients, including those in whom biliary scintigraphy had suggested obstruction, no abnormality of the common bile duct was identified. These results indicate that abnormalities of the bile ducts in patients with cystic fibrosis related liver disease are confined to the intrahepatic biliary tree and that common bile duct strictures do not contribute to either the progression or development of liver disease in these patients.

Adolescent

Intermediate filament expression in carcinoid tumours.

Twenty-eight carcinoid tumours were stained with monoclonal antibodies to epithelial and neural related intermediate filaments. All were found to express epithelial markers, and none expressed neural markers. These results support the theory that carcinoids are of epithelial, rather than neural crest origin.

Antibodies, Monoclonal

Access to hospital services in rural Minnesota.

A Minnesota Department of Health study on the financial condition of Minnesota's small, rural hospitals found that at least 12 hospitals were in precarious financial condition at the start of 1989, and many other hospitals were financially vulnerable. One-third or more of Minnesota's hospitals with fewer than 50 beds had negative net income in each year from 1984 to 1987. Using a standard of 30 minutes' maximum travel time for adequate access, the study revealed that about 19,000 Minnesotans in 14 counties currently have inadequate access to hospital services. Closing rural hospitals could leave additional Minnesotans without adequate access to hospital services. Given the financial condition of Minnesota's small, rural hospitals and the importance of maintaining access to hospital services in rural communities, the state may need to provide limited hospital subsidies to ensure access in geographically isolated areas.

Health Services Accessibility

Glomus tumours: an immunohistochemical profile of 11 cases.

We studied 11 glomus tumours immunohistochemically, with a panel of connective tissue and epithelial markers. Most tumours contained small nerve fibres located in connective tissue septae between groups of glomus cells, thus accounting for the frequent occurrence of pain associated with glomus tumours. All tumours stained positively for muscle-specific actin and vimentin. Immunostaining for high and low molecular weight cytokeratins, desmin, myoglobin, S-100 protein, neurofilaments and Factor VIII related antigen was negative. Our findings confirm and amplify the proposed smooth muscle histogenesis of glomus tumours. This immunohistochemical profile may be of diagnostic value in the differential diagnosis of atypical glomus tumours.

Adolescent

Semi-quantitative gallium-67 lung scanning as a measure of the intensity of alveolitis in pulmonary sarcoidosis.

Gallium-67 (67Ga) lung scanning has been applied for some years in pulmonary sarcoidosis to assess the activity of the alveolitis. Interpreting the scans, however, is difficult due to the low uptake of 67Ga in the disease process relative to background activity. In this study we have measured the mean parenchymal lung activity of 67Ga and have compared the lung activity to that at three remote sites, the liver, the abdomen and the thigh. The results obtained were compared with the percentage of lymphocytes in broncho-alveolar lavage fluid. There was a very good correlation with the lung-to-thigh uptake measurements and a much poorer correlation with the lung-to-liver and the lung-to-abdomen measurements. It was observed that steroid therapy reduced dramatically the correlation between the broncho-alveolar lavage findings and the 67Ga scan measurements. The results suggest that in patients not on steroid therapy, the 67Ga lung-to-thigh measurements may be used, similarly to the broncho-alveolar lavage lymphocyte counts, to identify those with high-intensity alveolitis from those with low-intensity alveolitis.

Adult

The prophylactic use of phenytoin during iopamidol contrast studies of the subarachnoid space.

Contrast examinations of the subarachnoid space are associated with side effects including convulsions. Attention has been given to the prophylactic use of anticonvulsants. We describe a simple oral regimen using the established anticonvulsant phenytoin that can be administered to short-stay patients and that achieves effective serum and CSF concentrations. A preliminary account of this work was presented to the British Pharmacological Society in January 1984 in London.

Contrast Media

A comparison between four simple methods for measuring glomerular filtration rate using technetium-99m DTPA.

Numerous centers perform glomerular filtration rate (GFR) measurements on patients undergoing renal imaging with Tc-99m DTPA. GFR measurement, however, does involve multiple blood samples taken over a 4-hour period, and this has led to attempts to simplify the technique by reducing the number of blood samples required and hence diminish the time taken to perform the test and the inconvenience to the patient. Four different simplified techniques for measuring GFR that have been reported in the literature are compared with a reference 2 blood sample method. Three of the methods do not require any blood samples but have standard errors of greater than 20 ml/min in adults and greater than 14 ml/min in children. The other method requires one blood sample, and if this is taken at 2 hours postinjection, the standard error is 9 ml/min in adults and 5 ml/min in children. The latter method is suitable for routine use in renography when accuracy is not of paramount importance.

Adult

GFR measurement by simulating constant infusion with data acquired using a CdTe detector. A feasibility study.

Conventional nuclear medicine methods for measuring glomerular filtration rate, GFR, are invalidated if the initial injection of radiopharmaceutical is tissued. An analytical method proposed by Veall and Gibbs in 1982 overcomes this difficulty but does require multiple blood samples. This paper investigates whether it is feasible to use the analytical method on data acquired with a CdTe detector system and thereby reducing to one the number of blood samples required. Synthetic data were used to investigate the effect of (a) duration of sampling (b) statistical noise and (c) non-stationarity on the GFR values derived by the Veall and Gibbs method. A sampling duration of 100 min is shown to be adequate and statistical noise is not a limiting factor. However, data fluctuations, mainly due to detector motion, do reduce the accuracy of the method. When the analytical technique is applied to data obtained using a CdTe detector on 40 patients the GFR values are similar to those derived by the conventional method (r = 0.957, Syx = 9.1 ml min-1). The technique is sufficiently attractive to warrant further studies to establish its absolute accuracy.

Computer Simulation

Effects of an inverted position on blood pressure, pulse rate, and deep tendon reflexes of healthy young adults.

This study reports the effects of an inverted position on pulse rate, blood pressure, and deep tendon reflexes of the biceps muscle, triceps muscle, and Achilles tendon. Twenty healthy adults were used as subjects. We collected data both before and after the subjects were in the inverted position for eight minutes on a specially designed tonic labyrinthine inverted table. A significant decrease in systolic blood pressure and all tendon reflexes was observed along with a significant increase in diastolic blood pressure (p less than .05). Pulse rate showed no change. The findings indicate that the inverted position is likely to be effective for decreasing muscle tone and systolic blood pressure. Although this study used healthy subjects, the inverted position may be used as a therapeutic technique, provided the clinician monitors closely the physiological effects on patients.

Achilles Tendon