PubMed Health⌕ Search

Biomedical subjects

T Cho

Publications and source records attributed to T Cho.

At least 73 records · Page 4Linked to original sources
PubMed1986

Isolation and characteristics of collagenolytic enzyme produced by Candida albicans.

In media containing collagen as the nitrogen source, the pathogenic yeast Candida albicans secreted a collagenolytic enzyme. Purification of the enzyme from a culture filtrate was achieved by DEAE-Sephacel chromatography at pH 6.7. The molecular weight was found to be 46,000 by 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the isoelectric point was at pH 4.2. The pH optimum lay between 3.5 and 4.0, and above pH 6.0, the enzyme underwent alkaline denaturation. The enzyme was heat labile, and a decrease in activity was found above 55 degrees C. The enzyme activity was inhibited by the addition of urea, cysteine, and pepstatin. No other inhibitor among those tested had any effect. The C. albicans enzyme degraded both the native acid-soluble collagen and the insoluble dentinal collagen.

Candida albicans↗
PubMed1986

Role of "wave line" (Doerr; Wellenlinie) of aorta in atherosclerosis.

Some aortas of neonates and of children have intimal wrinkles (wave line) which run closely pucked and horizontally across the longitudinal axis. Frequently the wave line corresponded with arteriosclerotic lesion. The purpose of this study is about the distribution of this structure and its relation to arteriosclerosis. 180 aortas ranging from neonates to 82 year olds were examined. The frequency of the wave line was 133 of 180 aortas (74%). The wave line already were visible in new born babies and were frequently found in the second and third decades. However, in cases over 30 years old its frequency decreased. It was suggested that this was due to increasing thickness of the intima and development of arteriosclerosis, which tend to obscure the wave line. The wave line could be classified into three patterns of distribution; (A) beginning from under the closure of the ductus arteriosus of the aorta, (B) beginning from the posterior wall of the celiac artery in the vicinity of the diaphragma and (C) beginning in the vicinity of the outside of lumbar artery running along the outside of each lumbar artery. These three distribution patterns were found in neonates and arteriosclerosis was--with advancing age--apt to correspond to the (C) pattern of wave lines. The histogenesis of the wave line was not clarified. It was apparent that these structures were closely related to arterial branching. Judging from these studies, there seemed to be some relation between the branching and the torsion resulting from the growth of the aorta.

Adolescent↗
PubMed1984

In flight negative pion assessments using time-of-flight technique.

Time-of-flight measurement was applied to obtain the energy spectra of the neutron emitted from tissue-equivalent plastic (TEP) exposed by pi- mesons. The separation of electrons and muons in beams was attempted. Neutrons from TEP exposed by pi- mesons at P pi = 500 MeV/c were separated from gamma-rays by the NE 213 liquid scintillator and the pulse-height analyzer. The double differential cross sections for neutron energy are obtained. The cross sections of the neutron energy distributions show a preponderance of low energy neutrons and a high energy tail extending to approximately 100 MeV.

Electrons↗
PubMed1984

[The applicability of pions to cancer radiotherapy. III. Measurement of x-ray and gamma-rays by NaI detector for the determination of the peak-region in pi- meson exposure].

A method of externally observing the stop-region of pi- meson for monitoring during exposure to a patient is discussed. Negative pi mesic X-rarys, gamma-rays and neutrons are emitted from the region where pi- mesons stop and produce stars. These radiations can be detected outside the exposed patient. Water phantom as normal tissue equivalent material was exposed by pi- mesons at various depths. The resulting gamma-ray yields were determined by counting the gamma-rays in coincidence with incident pi- mesons using a sodium iodide (NaI) detector. This type of gamma-ray measuring system is useful to make sure that the peak position of the depth-dose distribution in the patient is exactly situated at the desired one during exposure. It is suggested that the scintillation camera with a multiholecollimator is a powerful and convenient tool for the two dimensional peak positioning.

Gamma Rays↗
PubMed1984

Familial amyloidosis. A histopathological study.

Four autopsy cases of familial amyloidosis were reported. The ages of the patients ranged from 37 to 51 years consisting of 3 males and 1 female. They all complained of neurological symptoms. Histologically, amyloid deposition in familial amyloidosis was different in site and grade from that of other types of amyloidosis, showing heavy deposition in nervous and endocrine system but no differences were found referring to deposition in other tissues. Electronmicroscopically, the peripheral nervous tissue was examined and amyloid fibrils were found to be deposited massively in interstices of nerve fiber.

Adult↗
PubMed1984

Development of polyetherurethane sheet embedded with powdered charcoal for use in hemoperfusion.

This article describes the development of a polyetherurethane sheet embedded with powdered charcoal ( UPC ) for use in a hemoperfusion system. The UPC was 200 micron thick and the release of microparticles could be limited. The powdered charcoal used was selected for optimum pore size distribution and particle size (10-40 micron) to provide a maximum adsorption of bilirubin. The results of an in vitro adsorption test with this material showed an adsorption of bilirubin approximately 14 and 6 times higher than those by bead-type charcoal and XAD-7, respectively. Jaundiced dogs were subjected to direct hemoperfusion through a UPC column containing 36 g powdered charcoal. Effective decreases in bilirubin were observed, giving the maximum removal amounts of 78% in conjugated bilirubin and 76% in unconjugated bilirubin.

Adsorption↗
PubMed1983

[The applicability of pions to cancer radiotherapy. I. Experimental measurements of the capture and absorption of pions in polymer].

A future application of negative pions to radiotherapy has arrived at a promising stage. Negative pions, in addition to their good localization characteristics, offer an advantage of favorably influencing biological factors because of differences in the quality of radiation given to a) the treatment volume and b) the intervening normal tissue. By utilizing dose fractionation, the low dose to intervening normal tissue with its low LET allows these tissues to recover better than cells in the treatment volume. In this study the lucite phantom was bombarded with 150 MeV/c and 173 MeV/c negative pions and 173 MeV/c positive pions, respectively, by using the 12 GeV proton synchrotron of the National Laboratory for High Energy Physics (KEK). Range-energy relations in the lucite and the remaining curves of pions were observed. The observed range of pions in lucite agreed well with the theoretical prediction. The remaining curves show the different structures for pi+ and pi- mesons. Peak to plateau ratio is ten times.

Elementary Particles↗
PubMed1983

Morphologic study on aorta dot stained with Evans blue in normal and hypercholesterolemic rabbits.

When a normal rabbit is injected intravenously with Evans blue, focal blue areas showing strong permeability appear in a region of the aortic arch and in a region distal to the orifice of the aortic branches. These blue areas consist of the dot stained area but are not homogeneous blue area. The morphological changes in the intima of the dot stained area and the relationship between the appearance of dot stained area and lipid deposition in the aorta of cholesterol fed rabbit were investigated. Evans blue showed focal acceleration of the permeability at the region of the aortic arch as early as 10 minutes. Light and electron microscopically such dot stained areas showed the widening of subendothelial space, lifting of some endothelial cells, intracytoplasmic vacuoles and membranous structure, junctional dilatation, and enhanced permeability of peroxidase. In 2% cholesterol fed rabbits, lipid deposition showed a punctuate pattern similar to the dot stained area of normal rabbit.

Animals↗
PubMed1983

Cross-striated undulant structure of the aorta in neonates, children and young adults.

Some aortas of neonates and of children have intimal wrinkles which run closely packed and horizontally across the longitudinal axes. In the beginning of this century this structure was called "Wellenlinien", but there has been little investigation concerning their formation. Some wrinkle structures showed the transformation to atherosclerotic foci in infants. These wrinkles seemed to play an important role for atherogenesis in young subjects. In this paper, we will report the result of observations on these structures in neonates, children and young adults.

Adolescent↗