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Biomedical subjects

J Winter

Publications and source records attributed to J Winter.

At least 307 records · Page 17Linked to original sources
PubMed1979

New markers for Eubacterium lentum.

Of 37 strains of Eubacterium lentum and phenotypically similar organisms, 26 (70%) synthesized a corticoid 21-dehydroxylase and/or a 3 alpha-hydroxysteroid dehydrogenase. It appeared that the corticoid 3 alpha-hydroxysteroid dehydrogenase was identical to the bile acid 3 alpha-hydroxysteroid dehydrogenase. Steroid-metabolizing enzymes were found both in E. lentum and in phenotypically similar organisms. E. lentum is characterized by nitrate reduction and enhanced growth in the presence of arginine. Many phenotypically similar organisms possess either one or the other of the two markers. In contrast, using the steroid-metabolizing enzymes as markers, a "steroid-active" and a "steroid-inactive" group were established with minimal overlapping of metabolic characteristics. Synthesis of the steroid enzymes was positively correlated with production of gas from H2O2 and formation of H2S. A simple method for the detection of corticoid 21-dehydroxylase and 3 alpha-hydroxysteroid dehydrogenase, one or both of which were present in 92% of the steroid-active group, is described.

3-Hydroxysteroid Dehydrogenases↗
PubMed1979

Osteogenic sarcoma after retinoblastoma radiotherapy.

Development of osteogenic sarcoma after retinoblastoma radiotherapy in three patients, two of whom were siblings, is reported. Pluridirectional tomography and plain skull radiography demonstrated soft tissue masses, sinus opacification, and bone destruction and sclerosis in all three patients. Computed tomography reliably indicated the presence or absence of intracranial tumor extension in the two patients in whom it was performed. Radionuclide bone scanning was a useful adjunct for osteosarcomatous detection.

Eye Neoplasms↗
PubMed1978

The accuracy of predicting histologic grades of supratentorial astrocytomas on the basis of computerized tomography and cerebral angiography.

This report concerns a group of 49 patients who had been diagnosed as having gliomas on the basis of CT scans plus angiograms and for whom histologic proof was available. Ninety percent were found to be gliomas, 4% were metastases, and histology was unclear in the rest. Combining the CT criteria of inhomogeneous enhancement and surrounding edema with one or more of three angiographic signs (early venous drainage, stain, abnormal vessels) allowed a more confident diagnosis of glioblastoma.

Astrocytoma↗
PubMed1978

Extensions of paranasal sinus tumors and inflammatory disease as evaluated by CT and pluridirectional tomography.

CT and pluridirectinal tomography are compared in their ability to show the extent of paranasal sinus tumors or benign aggressive processes. Thirty-one cases are reviewed; CT was superior to pluridirectional tomography in showing spreads of tumor to all clinically important areas, including the infratemporal fossa, nasopharynx, orbit, and intracranial compartment. CT not only consistently allowed less equivocal interpretation, but also enabled us to qualify orbital involvement as intra- or extraconal, and to quantitate better both brain and infratemporal fossa involvement. We feel that CT scanning is the better way to determine the extent of such pathology.

Adult↗
PubMed1978

Metabolism of biliary steroids by human fecal flora.

Biliary excreted steroid hormones are metabolized by the intestinal flora. The metabolic pathways of deoxycorticosterone and progesterone, including the bacterial species involved, have been established. The pathways for other biliary steroids are unknown. Information on the biological activities of the metabolites is lacking, but methods for their investigation are now available. Evidence suggests that the formation of the metabolites is influenced by dietary habits, and that, in some cases, it may be controlled by suppression of the responsible bacteria.

Bacteria↗
PubMed1978

Steroids and apparent cerebral atrophy on computed tomography scans.

Computed tomography scans of 15 long-term steroid users showed varying degrees of apparent cerebral atrophy, not expected at their ages (8 to 40 years). Most were suffering from autoimmune diseases. There appeared to be some correlation between dosage and degree of apparent atrophy. There was surprisingly little clinical evidence of cerebral dysfunction associated with this apparent atrophy. In two of the cases, the appearance of the brain improved following decrease or cessation of steroid use. Speculations are made on possible causes.

Adolescent↗
PubMed1978

Giant intracranial aneurysms simulating brain neoplasms on computed tomography.

Giant intracranial aneurysms (GIA) may simulate brain neoplasms on computed tomography (CT) scans. We present three cases in which a GIA was mistakenly diagnosed as a brain neoplasm on the basis of CT findings. The correct diagnosis was made in each case by cerebral angiography. The possibility of GIA must be considered when a nonenhanced CT study shows a well circumscribed mass without edema at the base of the brain and contrast infusion reveals homogeneous or inhomogeneous enhancement.

Adult↗
PubMed1978

Computer tomography of the anterior mediastinum in patients with myasthenia gravis and suspected thymoma.

Six patients with myasthenia gravis and suspected thymoma underwent radiologic investigation using plain chest radiography, conventional anterior mediastinal tomography, and computed tomography. All underwent exploratory thoractomy within 1 month of the radiologic workup. In three of the five cases that proved to be thymoma, CT yielded significant diagnostic information that bore directly on the management and/or prognosis of the patient. We therefore believe that CT may be a valuable adjunct in the radiologic investigation of the patient with myasthenia gravis.

Adolescent↗
PubMed1978

Efficiency of utilization of a computed tomography scanner.

Efficient utilization of diagnostically effective but expensive computed tomography (CT) brain scanners requires understanding of time factors influencing patient throughput. In a study at UCLA Medical Center using an EMI Mark I brain scanner, the average number of patients studied was 16.3 per 15.5 hr workday, for an average of 52.7 min per patient. Of the patients, 51.5% were inpatients at UCLA, 45% received intravenous iodinated constrast infusion, and 33% had studies showing significant abnormalities. The x-ray tube was on 51.1% of the time the scanner facility was open, with scanning averaging 34.6 min per patient. The average number of images obtained was 10.4 per patient at 3.4 min per image. Patient handling, including contrast infusion, accounted for an additional 16.2 min per patient or 34.4% of the total time utilization. Anesthesia lengthened the procedure by 1 hr but was needed in only 4.5% of the cases. Flexible scheduling was essential, since 14% of the patients failed to keep their appointments or had their studies cancelled. These timing data suggest that the faster, more expensive CT scanners being introduced, while having diagnostic advantage for body scanning, will not significantly decrease cost per patient when used for brain scanning compared with the first generation machine studied.

Appointments and Schedules↗
PubMed1977

Determination of the isotope distribution in malate-14C with fumarase-negative lactic acid bacteria.

No fumarase activity could be found in whole cells or in cell-free crude extracts from Leuconostoc mesenteroides or Lactobacillus curvatus. The degradation of L-malate-4-14C by these organisms yielded more than 95% of the label as 14CO2. It is therefore recommended that these organisms, rather than Lactobacillus plantarum, should be used in the determination of isotope distribution in L-malate-14C, since L. plantarum exhibits a significant fumarase activity and thus randomizes malate prior to the decarboxylation of this substance by the malolactic enzyme.

Biological Assay↗
PubMed1977

Computed tomography of cerebral venous angiomas.

Six cases of venous angioma of the brain, a rare vascular malformation, were studied by means of computed tomography (CT), angiography, and other tests. In each case, angiography demonstrated the typical normal arterial phase and the network of abnormal veins that converge on a single large draining vein. In three cases, the CT scans showed rounded areas of high density not unlike neoplasms in appearance. In the other cases, the CT scan demonstrated the enlarged draining vein only. The CT scan findings, although not specific, may alert the radiologist to the possibility of this lesion and may lead to its demonstration through angiography.

Adult↗
PubMed1977

Computed tomography and transabdominal ultrasound in the evaluation of the prostate.

The prostates of eight patients scheduled to undergo prostatectomies were studied prospectively by transabdominal gray scale ultrasound and computed tomography. Computed tomography gave excellent visualization of prostate morphology and pelvic anatomic relationships. Ultrasound provided more histopathologic information in the cases of carcinoma and prostatitis. Additionally, its capacity to distinguish surgical capsule from adenoma, in benign prostatic hypertrophy, made it more useful for volume determinations.

Humans↗