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K Katoh

Publications and source records attributed to K Katoh.

At least 271 records · Page 15Linked to original sources
PubMed1986

[Immunohistochemical study of subependymal giant cell tumor associated with tuberous sclerosis].

Subependymal giant cell tumors from four patients associated with tuberous sclerosis were examined by peroxidase antiperoxidase (PAP) immunohistochemistry for neuron specific enolase (NSE), glial fibrillary acidic protein (GFAP) and S-100 protein. The tumor cells were grouped into three morphological types: ganglion-like pyramidal cells, swollen gemistocytic cells and fibrillated spindle cells. There was little difference in immunohistochemical property between these cell types in each case, suggesting that the tumor cells of different cell types have a same origin. The majority of the tumor cells was intensely stained for NSE in every case. On the other hand, for GFAP none of the tumor cells was stained in two cases, and the minority was weakly stained in the other two cases. The intensity of staining of the tumor cells for S-100 protein varied from case to case. Our findings together with those of others show the definite immunohistochemical characteristics of subependymal giant cell tumors with tuberous sclerosis, i.e., strong positivity for NSE in contrast to their negativity or weak positivity for GFAP. However, these findings do not necessarily suggest that the tumor is of neuronal origin, because in the case of neoplasms the significance of the presence of NSE as indicative of neuronal origin is open to question.

Adolescent↗
PubMed1985

[The establishment of the assay-system of blood adrenal steroids in the method of gaschromatograph/mass spectrometry (GC/MS)].

In this study, we established a method for the quantitative measurement of native adrenal steroids with GC-MS equipped with capillary column (cross-linked methyl silicone 25 m X 0.2 mm I.D., 0.11 m thin film). 1 ml of serum sample containing 5 alpha-cholestane as internal standard (IS) was elicited by organic solvent using extrelunt column. These samples were derived by n-butylboronic acid, o-methylhydroxylamine and trimethyl-silylating agents, then were finally applied to GC-MS. The intensities of molecular ions were used for the measurement of the serum concentration of steroids. The molecular ion peaks of steroids were obtained at m/z460 (17 alpha-hydroxyprogesterone; 17OHP), m/z548 (corticosterone; B), m/z470 (11-deoxycortisol; S), m/z417 (pregnenolone; PL), m/z372 (progesterone; PT), m/z558 (cortisol; F), m/z389 (dehydroepiandrosterone; DHEA), m/z371 (estrone; E1), m/z416 (estradiol; E2), m/z504 (estriol; E3), m/z389 (testosterone; T), m/z344 (androstenedione; A) and m/z372 (IS). The curve of calibration for each steroid showed good linearity. The sensitivities of the GC/MS method were less than 5pg/one shot of each sample. The coefficients of variations of accuracies and precisions in this GC/MS method were less than 15% of each steroid. The samples from normal subjects after metyrapone and ACTH loading tests, and the patients of congenital adrenal hyperplasia showed a good correlationship between the data of GC/MS and the data of RIA after sephadex LH-20 column-chromatography. These results implied the usefulness of our system in clinical application. Moreover, this assay takes only 3 hrs. Thus it saves much time in comparison with the time-consuming radioimmunoassay system.

Adrenal Cortex Hormones↗
PubMed1985

Pathologic features of Behçet's syndrome: a review of Japanese autopsy registry data.

The data recorded from 170 autopsies of patients with Behçet's syndrome in Japan during the period from 1961 to 1976 were analyzed. The patients had been in the second to the eighth decade of life, and the ratio of males to females was 5 to 2. A wide spectrum of pathologic findings was observed, with involvement of neurologic, ophthalmic, cardiovascular, pulmonary, gastrointestinal, visceral, genitourinary, and mucocutaneous systems. Some of the common acknowledged clinical features of the syndrome, such as oral ulcers, synovitis, retinal and cutaneous vasculitis, and venous occlusions, were underreported. This apparent discrepancy in an autopsy series may be due to the effects of treatment or the healing process, as well as to the possible incompleteness of the postmortem examination. The accessibility of recorded data in a national autopsy registry offers a unique opportunity for review of the pathologic features of Behçet's syndrome.

Adult↗
PubMed1985

Affinity chromatography of urokinase on an agarose derivative coupled with pyroglutamyl-lysyl-leucyl-argininal.

Pyroglutamyl-lysyl-leucyl-argininal (Pyr-Lys-Leu-Argal) immobilized on gel matrix through the epsilon-amino group of its lysine residue was shown to be an efficient biospecific affinity adsorbent for purification of urokinase. Pyr-Lys-Leu-Argal dibutylacetal, a precursor of this immobilized ligand, was synthesized by a fragment condensation procedure, in which one of the thermolysin-digestion products of leupeptin dibutylacetal, H-Leu-Argal dibutylacetal, was used as a key intermediate. The precursor was coupled to CH-Sepharose 4B with the aid of a water-soluble carbodiimide, and its acetal protecting group was then removed by mild acid treatment to free the essential aldehyde function. The Sepharose derivative thus prepared was shown to adsorb urokinase selectively and effectively from a crude human urine preparation at neutral pH and to release the bound enzyme under mild acidic conditions. The present technique afforded a highly purified urokinase preparation abundant in the high-molecular form with 90% recovery. The complex formed between urokinase and the immobilized ligand was found to have a dissociation constant of about 2 X 10(-4)M.

Chemical Phenomena↗
PubMed1985

Effects of secretagogues on membrane potential and input resistance of pancreatic acinar cells of sheep.

The effects of acetylcholine, short-chain fatty acids and peptide hormones on membrane potential and input resistance of the pancreatic acinar cells of sheep were investigated using intracellular glass microelectrodes. The resting membrane potential and input resistance were -28.0 +/- 4.3 mV (mean +/- SD, inside negative, n = 23) and 2.4 +/- 1.7 M omega, respectively. The application of acetylcholine, short-chain fatty acids (acetate, butyrate and caprylate) and peptide hormones (caerulein and bombesin) always caused depolarisation accompanied by a marked reduction in input resistance. The equilibrium potentials of acetylcholine and caprylate were -13.5 and -12.8 mV, respectively.

Acetates↗
PubMed1985

Pathologically defined neuro-, vasculo-, entero-Behçet's disease.

Behçet's disease is characterized clinically by the presence of a diagnostic triad of stomatitis, genital ulceration and uveitis. Multiple other organ systems may be involved. Prognosis is related to the presence of central nervous system, vascular or intestinal involvement. This report describes the pathology of neuro-, vasculo- and entero-Behçet's disease in a single patient.

Adult↗
PubMed1984

Histogenesis, cytodifferentiation, and its subcellular steroidogenic sites in the virilizing ovarian Leydig cell tumor: light microscopic dry-mounting radioautography for [3H]cholesterol and electron microscopic cytochemistry for 3 beta-hydroxysteroid dehydrogenase activity.

A case of a virilizing ovarian Leydig cell tumor in a 38-year-old woman with a marked elevated plasma testosterone level was investigated using light microscopic dry-mounting radioautography and electron microscopic cytochemistry. Following a total abdominal hysterectomy and bilateral salpingo-oophorectomy, the plasma testosterone level decreased abruptly. Light microscopic dry-mounting radioautography for [3H]cholesterol showed silver grains localized mainly over the cytoplasm of the neoplastic Leydig cells which were of three different cell types: fibroblast-like cells, Leydig cells (steroid-secreting cells), and transitional cells (partially or incompletely differentiated Leydig cells). Reaction products for 3 beta-hydroxysteroid dehydrogenase activity were localized on the tubular or lamellar cristae and inner membranes of the mitochondria, and on the membranes of smooth endoplasmic reticulum in the transitional cell as well as in the Leydig cell. From these observations, it is suggested that the Leydig cell tumor is derived from the fibroblast-like cell and from the transitional cell, morphologically falling between the fibroblast-like cell and the Leydig cell, has fine structural evidence of steroidogenic activity, and has an ability to secrete testosterone.

3-Hydroxysteroid Dehydrogenases↗
PubMed1984

Effects of acetylcholine and short-chain fatty acids on acinar cells of the exocrine pancreas in sheep.

In order to investigate the actions of acetylcholine and short-chain fatty acids on acinar cells of the exocrine pancreas of sheep, measurements of amylase release and 45Ca efflux from superfused segments, as well as changes in membrane potential, input resistance and equilibrium potential in the acinar cells, were carried out in vitro. The application of acetylcholine or short-chain fatty acids caused a dose-dependent increase in amylase release from the superfused tissue segments. The amylase release evoked by 10(-3) M-short-chain fatty acids containing 2-8 carbon atoms increased with increasing carbon number, up to 5 (i.e. it was maximum with iso-valerate, which has 5 carbon atoms). The amylase release stimulated by acetylcholine (5.5 X 10(-6) M) or caprylate (10(-3) was accompanied by an increase in 45Ca efflux, and was significantly reduced by the removal of extracellular Ca2+. The stimulating effect of caprylate (10(-3) M) on amylase secretion was also observed in superfused segments of the guinea-pig, but not in those of the mouse, rabbit or hamster. The resting membrane potential and input resistance of acinar cells of sheep pancreas were -31.1 +/- 1.6 mV and 2.7 +/- 0.7 M omega (means +/- S.E. of means), respectively. The application of acetylcholine or short-chain fatty acids always depolarized the cell membrane and reduced the input resistance. The effect of short-chain fatty acids was observed in the presence of atropine (1.4 X 10(-6) M). The equilibrium potentials for acetylcholine and butyrate were -15.0 +/- 0.8 and -16.0 +/- 1.1 mV, respectively. It is concluded that the cellular secretory process evoked by acetylcholine is qualitatively similar to that of short-chain fatty acids, and that Ca2+ ions might be an important mediator for these secretagogues in the acinar cells of the pancreas of sheep.

Acetylcholine↗