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Biomedical subjects

K Kikuchi

Publications and source records attributed to K Kikuchi.

At least 1,315 records · Page 73Linked to original sources
PubMed1981

[Mechanism of suppression on cellular immunity in experimental brain tumor rats (author's transl)].

The mechanism of the suppression on the cellular immunity was analysed in experimental brain tumor rats. The tumor used in this experiment was a 3-methylcholanthrene induced fibrosarcoma. The tumor cell was inoculated into the caudate nucleus of the rats with a Hamilton microsyringe. When spleen cells from brain tumor rats were added to the PHA blastogenesis system, impairment of the normal lymphoproliferative response to the PHA was detected as early as on the third day and continued until the ninth day after inoculation. After the depletion of glass adherent cells, the residual cells from the spleen could not suppress the normal lymphoblastogenesis by the PHA. After the depletion of T cells by anti-T cell sera and complement, however, the residual cells from the spleen still suppressed the normal lymphoblastogenesis. Glass adherent cells were able to phagocyte the latex particles. From these findings, the suppressor cell responsible for the suppression of the normal lymphoblastogenesis by the PHA was considered to be macrophage and suppressor T cell did not play a role in the suppression of the PHA responses in this experimental model. The sera from brain tumor rats could not inhibit the proliferative responses of lymphocytes to PHA. Thus the possibility of the existence of suppressive factors in the sera was also negligible.

Animals↗
PubMed1981

Immunochemical characterization of murine B16 melanoma-associated antigens and their detection in sera of tumor-bearing hosts by radioimmunoassay.

Radioimmunoassay, using radiolabeled melanoma-associated antigens (MAA), rabbit anti-B16 melanoma serum and Staphylococcus aureus Cowan I, was developed for the detection of MAA in tumor tissues as well as in sera of B16 melanoma-bearing C57BL/6 mice. MAA were partially purified from 3 M KC1 extract of murine B16 melanoma tissue by affinity column chromatography using anti-B16 serum and concanavalin A. The content of MAA was high in B16 melanoma extract, much less in allogeneic Harding Passey melanoma, and very small in fetal and normal tissues including skin and brain. The amount of circulating MAA released from the tumor into the blood of B16 tumor-bearing C57BL-6 mice was linearly proportional to the size (cube root of weight) of the growing tumor, providing a rational basis for immunodiagnosis of malignant melanoma. Immunochemical data suggest that MAA which are extractable with 3M KC1 from B16 melanoma are glycoproteins with molecular weights of 54,000, 68,000 and 94,000 daltons.

Animals↗
PubMed1981

[Clinical studies on tobramycin by intravenous drip infusion for Pseudomonas aeruginosa infection in chronic respiratory diseases (author's transl)].

Tobramycin (TOB) was administrated by intravenous drip infusion for 1 hour, to 15 patients with intractable chronic respiratory tract infections due to P. aeruginosa, and the following results were obtained. 1. Criteria of clinical effects We have made new criteria for the evaluation of the therapeutic effects on respiratory tract infections (Tables 1, 2). Clinical items were divided into 4 grades and radiographic ones into 6 to 11 grades. Each item was separately scored as followed; excellent was scored as 1 point when 3 or more grade upward-shifts were seen after treatment, good as 2 points in case of 2 grade upward-shifts, fair as 3 points in case of 1 grade upward-shift, unchanged as 4 points in case of no shift, impairment as 5 points in case of downward-shift. The integrated evaluation of the items was made according to the average points for the evaluated items; overall excellent was 1.9 or less, overall good 2.0 to 2.9, overall fair 3.0 to 3.5 and overall poor as 3.6 or more. 2. Clinical effects Overall clinical effects were evaluated as good in 7 cases, fair in 4 and poor in 4 out of 15 patients, and rate of good score was 46.7%. According to the dosage groups, rate of good score was 50% in the dose of 60 mg three times a day, 0% in the dose of 90 mg twice a day and 62.5% in the dose of 120 mg twice a day. Eradication rate of P. aeruginosa was 33.3%. Neither adverse side effects nor abnormal laboratory findings were observed.

Adult↗
PubMed1980

Lesions of the upper gastrointestinal tract in patients with chronic renal failure.

Endoscopy of the upper gastrointestinal tract was performed on 84 patients with end-stage chronic renal failure undergoing hemodialysis. Gastric acid secretion and fasting plasma gastrin levels were also examined in these patients. Hemorrhagic gastritis was most frequently observed (23 cases) followed by erosive gastritis (18 cases). No patients had gastric ulcers. Duodenal ulcers were observed in only two patients. Gastrointestinal bleeding was observed in 15 cases (17.9%). Thirteen of these 15 cases had hemorrhagic gastritis, one of which had a duodenal ulcer as a complication. Fasting plasma gastrin levels (359.6 +/- 336.5 pg/ml) were significantly higher than those of normal subjects (35.2 +/- 37.1 pg/ml), but no acceleration in gastric acid secretion was observed either in the basal condition (BAO 0.8 +/- 0.7 mEq/h) or following tetragastrin stimulation (MAO 9.0 +/- 6.9 mEq/h). Our results were inconsistent with the previous reports that high frequencies of peptic ulcers and increased gastric acid secretion were observed in patients with chronic renal failure. Our data suggest that the defensive factors rather than the aggressive factors of the gastroduodenal mucosa may be involved in chronic renal failure.

Adolescent↗
PubMed1980

Electric birefringence of ionized polypeptides in solution and the effect of high electric fields on the helix-coil transition.

Electric birefringence and circular dichroism measurements have been made on solutions of two po!y (L-lysine) homologs. The specific Kerr constant and the molar ellipticity at 222 nm of poly (L-alpha, gamma-diaminobutyric acid hydrochloride) in methanol/water mixtures underwent an abrupt change between 75 and 80 vol% methanol at 25 degrees C, corresponding to a solvent-induced helix-coil transition. On the helix side of the transition region, i.e., between 78 and 80 vol% methanol, anomalous birefringence transients indicative of field-induced helix-to-coil transition were observed at high fields. In the case of poly (L-ornithine hydrobromide) in methanol/water mixtures, a helix-coil transition was induced between 93 and 98 vol% methanol and anomalous birefringence transients were observed between 96 and 98 vol% methanol. The double logarithmic plots of the steady-state specific birefringence versus the square of field strength for various solvent compositions and polymer concentrations could be superimposed on one another by horizontal and vertical shifts, except for the range where anomalous birefringence transients were observed. This enabled us to estimate the threshold field strength.

Journal Article↗
PubMed1980

Purification and subunit structure of a high-molecular-weight phosphoprotein phosphatase (phosphatase II) from rat liver.

1. Phosphatase II is a form of phosphoprotein phosphatase originally found in rat liver extract; it has a molecular weight of 160 000 by gel filtration and is highly active towards phosphorylase alpha. This phosphatase has been purified 1800-fold by using DEAE-cellulos (DE-52), aminohexyl--Sepharose-4B, protamine--Sepharose-4B and Sephadex G-200 chromatography. Throughout the purification steps, the original molecular weight and substrate specificity of phosphatase II were almost perfectly preserved. 2. The product of the final purification step migrated predominantly as a single protein band on non-denaturing gel electrophoresis. Sodium dodecyl sulfate gel electorphoresis revealed that the enzyme contains two types of subunit, alpha and beta, with molecular weights of 35 000 and 69 000, respectively. When treated with 0.2 M 2-mercaptoethanol at -20 degrees C, phosphatase II was dissociated to release the catalytically active alpha subunit. The beta subunit may be catalytically inactive but interacts with the alpha subunit so that phosphatase II becomes much less susceptible than the alpha subunit to inactivation by ATP or pyrophosphate.

Animals↗
PubMed1980

UDP-N-acetylglucosamine 2'-epimerase of rat hepatoma and its comparison with the enzyme of rat liver.

UDP-N-acetylglucosamine 2'-epimerase was partially purified from Yoshida sarcoma, a strain of rat ascites hepatoma, by (NH4)2SO4 precipitation followed by TEAE-cellulose chromatography. The purified enzyme was inhibited by CMP-N-acetylneuraminic acid to similar extent to partially purified rat liver 2'-epimerase. Although the two enzymes were also similar in Km for UDP-N-acetylglucosamine, they were differentiated by chromatography on TEAE-cellulose, DEAE-Sephadex and hydroxyapatite, tumor enzyme being less tightly bound to these columns than liver enzyme. Similar chromatographic difference was also noted between 2'-epimerases of mouse liver and mouse Ehrlich asites carcinoma.

Animals↗
PubMed1980

Effect of ethanol treatment on high molecular weight phosphoprotein phosphatases of rat liver.

When the crude phosphoprotein phosphatase fraction of rat liver cytosol was treated with 80% aqueous ethanol at room temperature, the activity with phosphorylase alpha as substrate was increased by 110%, but those with glycogen synthase D and phosphohistone were decreased by 53 and 34%, respectively. Chromatography of the ethanol-treated fraction on DE-52 revealed that while phosphoprotein phosphatase IA (Mr=69,000) remained to exist even though it was reduced, phosphatases IB (Mr=-300,00) and II (Mr=160,000) were totally replaced by a new phosphatase form with an approximate molecular weight of 35,000. This low molecular weight form has been designated phosphatase III. When partially purified phosphatases IB and II were separately treated with ethanol, they were converted to phosphatase III. These results suggest that phosphoprotein phosphatases IB and II, but IA, contain phosphatase III as a subunit. Phosphatases IB and II, however, must differ in structure since "IB to III" is accompanied by an increase in phosphorylase phosphatase activity much greater than that for "II to III"

Animals↗