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Biomedical subjects

T Kikuchi

Publications and source records attributed to T Kikuchi.

At least 523 records · Page 29Linked to original sources

Ultrasonic tissue characterization of blood clots.

Ultrasonic tissue characterization based on an analysis of the power spectrum of backscattered signals obtained with ultrasound was used to distinguish morphologic components of blood clots. The three morphologic features for which discrimination was attempted were loose fibrin, red-cell, and dense fibrin clots. The UTC was able to distinguish the morphologic blood components tested. This in vitro work was based on the analysis of parameters related to ultrasound-tissue interaction and on inferences related to the physical properties of scatterer properties (scatterer size, scatterer concentration, and ratio of scatterer to medium acoustic impedances). The ability to distinguish these blood-clot components suggests that UTC may be able to distinguish red from white thrombi and to assess the structures and changes within thrombi associated with the age of the thrombus, their mechanical properties, and treatment monitoring.

Blood Coagulation↗

Interactions of 7-[3-(4-[2,3-dimethylphenyl]piperazinyl)-propoxy]-2(1H)-quinolinone binding in rat striatum: effects of lesions.

7-[3-(4-[2,3-Dimethylphenyl]piperazinyl)propoxy]-2(1H)-quinolinone (OPC-4392), a presynaptic dopamine autoreceptor agonist and postsynaptic D-2 receptor antagonist (Yasuda et al., Life Sci. 42: 1941-1954, 1988), was studied for its binding characteristics at 3H-SCH 23390-labeled dopamine D-1 receptors and 3H-spiperone-labeled dopamine D-2 receptors in rat striatum. The binding affinity of OPC-4392 for 3H-spiperone-labeled D-2 receptors was 500 times higher than for 3H-SCH 23390-labeled D-1 receptors. 6-Hydroxydopamine lesions of striatum and high-frequency current lesions of medial forebrain bundle did not affect the competition of OPC-4392 for 3H-spiperone binding. Kainic acid lesions of striatum significantly changed the one-site model fit to a two-site model fit of the competition curve of OPC-4392 for 3H-spiperone binding, suggesting that OPC-4392 competed with 3H-spiperone binding differently for postsynaptic dopamine D-2 receptors and for presynaptic dopamine autoreceptors.

Animals↗

Nuclear localization of antigens detected by a monoclonal antibody against a synthetic peptide of rfp finger protein.

A monoclonal antibody (MAb) was generated against a synthetic peptide corresponding to amino acids 148 to 163 of the rfp protein with zinc finger domains. The MAb, designated RFP-1 (IgM), which was positive with the immunizing peptide in enzyme-linked immunosorbent assay, was reactive in immunoblotting with an in vitro translated rfp product as well as with native proteins in cell extracts made from mouse testis and HL-60 human leukemia cell line, both of which were previously shown to express high levels of rfp mRNA. When HL-60 cells were fractionated into nuclear and cytoplasmic components, the protein reactive with RFP-1 MAb was detectable only in the nuclear fraction. By the avidin-biotin complex immunoperoxidase method, this MAb strongly stained over 90% of the nuclei of human and mouse spermatogenic cells, except mature spermatozoon, and of human testicular tumor cells. In other human adult tissues, up to 60% of positive cells were observed. These antibody activities were clearly absorbed by pre-incubation of RFP-1 MAb with the immunizing peptide. These results thus indicated that RFP-1 MAb recognizes a nuclear protein which is expressed at high levels in male germ cells.

Amino Acid Sequence↗

Antibody against the C-terminal portion of dystrophin crossreacts with the 400 kDa protein in the pia mater of dystrophin-deficient mdx mouse brain.

The mdx mouse is an animal model for X-linked Duchenne muscular dystrophy. A polyclonal antibody against a synthetic peptide IV equivalent to the C-terminal portion (amino acids 3495-3544) of dystrophin crossreacted with a 400 kDa protein in the brain and the spinal cord of mdx mouse, as well as in the control B10 mouse. However, the protein did not crossreact with the polyclonal antibody raised against the N-terminal portion of dystrophin peptide I (amino acids 215-264). Immunofluorescent micrography revealed that the outside of the small arteries and the pia mater of the brain strongly reacted with the anti-peptide IV antibody. These results strongly suggest the presence of a crossreactive protein other than dystrophin, possibly a dystrophin-related autosomal gene product, in the pia mater.

Animals↗

Constituents of the leaves of Woodfordia fruticosa Kurz. I. Isolation, structure, and proton and carbon-13 nuclear magnetic resonance signal assignments of woodfruticosin (woodfordin C), an inhibitor of deoxyribonucleic acid topoisomerase II.

Woodfruticosin (woodfordin C), a new cyclic dimeric hydrolyzable tannin having an inhibitory activity toward deoxyribonucleic acid (DNA) topoisomerase II, has been isolated from the leaves of Woodfordia fruticosa Kurz (Lythraceae) along with three known flavonol glycosides and three known flavonol glycoside gallates. The structure of wood fruticosin (woodfordin C) was determined by the use of two-dimensional nuclear magnetic resonance (2-D NMR) spectroscopy including heteronuclear multiple quantum coherence (HMQC) and heteronuclear multiple bond connectivity (HMBC) techniques. Detailed analyses of the proton and carbon-13 NMR (1H- and 13C-NMR) spectra of six known flavonoids were performed.

Carbon Isotopes↗

Scopadulcic acid B, a new tetracyclic diterpenoid from Scoparia dulcis L. Its structure, H+, K(+)-adenosine triphosphatase inhibitory activity and pharmacokinetic behaviour in rats.

The structure of scopadulcic acid B (2, SDB), a major ingredient of the Paraguayan herb "Typychá kuratũ" (Scoparia dulcis L.), was elucidated mainly by comparison of its spectral data with that of scopadulcic acid A (1). SDB inhibited both the K(+)-dependent adenosine triphosphatase (ATPase) activity of a hog gastric proton pump (H+, K(+)-ATPase) with a value of 20-30 microM for IC50 and proton transport into gastric vesicles. Pharmacokinetic studies of SDB in rats indicated that plasma SDB concentrations after i.v. injection of the sodium salt of SDB (SDB-Na) were described reasonably well by a two-compartment open model with Michaelis-Menten elimination kinetics. Plasma concentrations after oral administration of SDB-Na or SDB showed a much slower decline than what was expected following the i. v. study. It was suggested that the sustained plasma level of SDB after oral administration of SDB-Na or SDB was accounted for by relatively slow but efficient gastro-intestinal absorption in rats.

Adenosine Triphosphatases↗

Constituents of a fern, Davallia mariesii Moore. I. Isolation and structures of davallialactone and a new flavanone glucuronide.

A new gamma-lactone derivative named davallialactone (4) and the 7-O-beta-D-glucuronide of (+/-)-eriodictyol (5a) have been isolated from Davallia mariessi Moore along with caffeic acid (1), 4-beta-D-glucopyranosylcaffeic acid (2) and 4-O-beta-D-glucopyranosyl-p-coumaric acid (3). The structures of the new compounds were determined by chemical and spectroscopic methods including two-dimensional nuclear magnetic resonance (2D NMR) techniques, especially 1H-detected heteronuclear multiple-bond multiple-quantum coherence and long-range C-H J-resolved 2D NMR techniques.

Animals↗

Studies on cytotoxic constituents in pericarps of Mallotus japonicus. IV.

Two new phloroglucinol derivatives, isomallotolerin (1) and isomallotochromanol (2), were isolated from the cytotoxic fraction of the pericarps of Mallotus japonicus. The new derivatives were identified as 3-(3-methyl-2-hydroxybut-3-enyl)-5-(3-acetyl-2,4-dihydroxy-5-methy l-6- methoxybenzyl)-phlorisobutyrophenone (1) and 6-acetyl-5,7-dihydroxy-8-(3-acetyl-2,4-dihydroxy-5-methyl-6-methoxybenzy l)-2,2- dimethyl-3-hydroxychroman (2) from chemical and spectral data. Isomallotolerin and its acetate were found to be cytotoxic to KB cell line.

Antineoplastic Agents, Phytogenic↗

Changes in vascular wall production of prostacyclin and thromboxane A2 in spontaneously hypertensive rats during maturation and the concomitant development of hypertension.

The purpose of this study was to clarify how the metabolism of vascular prostacyclin (PGI2) and thromboxane (TX) A2 in spontaneously hypertensive rats (SHR) is involved in aging and development of hypertension. We removed the aortic walls from 5-week-old and 20 to 25-week-old SHR and age-matched Wistar Kyoto rats (WKY). At 5 weeks of age, there was no significant difference in basal and maximal (arachidonic acid 0.1 mM) 6-keto-PGF1 alpha production between SHR and WKY, but the TXB2 generation in the SHR aortic wall was markedly enhanced as compared with that in WKY. At 20 to 25 weeks of age, the SHR aortic wall synthesized about 1.5 times more 6-keto-PGF1 alpha in the basal condition and twice as much as in the maximal condition as did the WKY wall. However there was no significant difference in TXB2 production between SHR and WKY. Age-dependent increase of vascular 6-keto-PGF1 alpha was greater in SHR than in WKY. Moreover, the maximal/basal 6-keto-PGF1 alpha production ratio increased with age in SHR, but not in WKY. The synthesis of vascular TXB2 was enhanced with age in WKY, but did not change with age in SHR. These data suggest that not only the enhanced basal generation of vascular 6-keto PGF1 alpha but also a much greater reservoir of 6-keto-PGF 1 alpha synthesis in SHR was induced by both hypertension and maturity. The increased production of vascular TXB2 in young SHR may affect the development of hypertension.

6-Ketoprostaglandin F1 alpha↗

Metabolism of illudin S, a toxic principle of Lampteromyces japonicus, by rat liver. I. Isolation and identification of cyclopropane ring-cleavage metabolites.

1. Illudin S, a toxic principle of the basidiomycete Lampteromyces japonicus, was incubated with rat liver 9000 g supernatant and its metabolites studied. 2. Two metabolites, M1 and M2, were isolated and identified as cyclopropane ring-cleavage compounds by n.m.r., i.r. and mass spectral analyses. Moreover, M2 contained a chlorine atom. 3. On the basis of detailed analyses of the 2D n.m.r. spectra and differential nuclear Overhauser effect experiments, the previous assignments of the cyclopropane carbons of illudin S were revised.

Animals↗

[Evaluation of serum S100ao protein in patients with renal cell carcinoma].

In order to evaluate the clinical significance of S100ao protein, we measured serum S100ao protein in 36 patients with renal cell carcinoma by EIA developed by Kimura et al. In addition, the distribution of S100ao protein was studied by the immunohistochemical method. Previous study demonstrated that mean level of serum S100ao protein in healthy volunteers was 203 +/- 107 pg/ml, therefore the cut off level was set to 524 pg/ml. The results obtained in this study were as follows: 1) The mean level of serum S100ao protein was 1162 +/- 2056 pg/ml, and its positive rate was 44% in 36 patients with renal cell carcinoma. When the patients were divided into 2 groups according to tumor stage, the mean level of serum S100ao protein in the high stage group was significantly higher than that in the low stage group (p less than 0.01). 2) In the sequential study of serum S100ao protein, patients with progressive disease showed a gradual increase in the level of serum S100ao protein while patients with no evidence of tumor showed a normal level of serum S100ao protein. 3) There was no correlation between the level of serum S100ao protein and the histological grade of renal cell carcinoma. 4) Immunohistochemical analysis (10 cases) showed that S100ao protein was observed in all of 10 renal cell carcinomas. Thus, the present study suggests that serum S100ao protein might be a useful clinical marker especially in monitoring patients with renal cell carcinoma.

Adult↗

[Percutaneous dissolution of uric acid and cystine stones causing acute ureteral obstruction].

Four cases with ureteral obstruction due to uric acid or cystine stones were treated successfully by percutaneous irrigation with sodium bicarbonate or tromethamine-E. These cases underwent percutaneous nephrostomy for the reason of prolonged complete obstruction (case 1), sustained pyelonephritis (case 2) or decreased renal function (case 3 and 4). Two catheters were placed through the nephrostomy tract before irrigation, 6 Fr. ureteral catheter just above the ureteral stone and 10 Fr. pigtail or 12 Fr. Malecot catheter in the renal pelvis. The ureteral stones were markedly reduced in size and passed spontaneously after 6-11 days' duration of irrigation in three cases. In case 2, the remaining stone was removed transurethrally after 14 days' duration of irrigation, and was found to be composed of organic matrix. Percutaneous dissolution is considered to be a safe and reliable method and may be an alternative way of treating uric acid or cystine stone causing acute ureteral obstruction.

Acute Disease↗

[Analysis of cytolytic activity and cell surface phenotypes of lymphokine activated killer cells stimulated with R-IL 2 and an anti-CD 3 antibody].

We analyzed cytolytic activity and cell surface phenotypes of LAK (lymphokine activated killer) cells which were stimulated with recombinant IL-2 and an anti-CD3 antibody. This study involved 9 patients with astrocytomas, one patient with ganglioglioma, and one patient with medulloblastoma and their ages ranged between 5 and 80yr. Peripheral blood lymphocytes were separated from about 40 ml venous blood on a Ficoll-Paque gradient. After PBL's were cultured with r-IL 2 and anti-CD 3 antibody for about two weeks, more than 10(8) LAK cells could be obtained. Their cytolytic activity was measured by standard 4 hours-51Cr release assay and K 562, Daudi, U 251 MG, MCF-7, and autologous tumor cells were used as target cells. Their surface phenotypes (CD 3, CD 4, CD 8, CD 16, CD 25, Leu 7, HLA-DR) were measured by FACS. These LAK cells showed weaker killing activity against all kinds of tumor cells than usual LAK cells (LAK cells stimulated with r-IL 2 alone) did. Their surface phenotypes were more sensitive to CD 3 and less sensitive to CD 16 and Leu 7 than those of usual LAK cells. One of weak points of so-called LAK therapy is that many PBL's have to be obtained by leukapheresis and because of that, it is difficult to undertake LAK therapy to children or elderly patients. However, by using an anti-CD 3 antibody, enough LAK cells as effector of LAK therapy could be obtained more easily.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Evaluation of correlation between the disappearance rate of indocyanine green and the maximum removal rate].

The disappearance rate of indocyanine green (K.ICG) and the maximum removal rate (Rmax) usually correlate with each other. However, in some cases it was shown there was a dissociation between them. We investigated the relationship between the two rates in 146 subjects. K.ICG and Rmax correlated strongly with a correlation coefficient of 0.749 (p less than 0.001). Sixty-six cases were included in the limits of 95% confidence, and the other 80 cases outside the limits were defined as dissociated cases. Among them a lower Rmax rate as compared to the K.ICG rate was found in many cases of obstructive jaundice. Particularly a lower K.ICG rate compared to the Rmax rate was found in many cases of liver cirrhosis accompanied by esophageal varices and idiopathic portal hypertension. On the other hands, we performed multiple regression analysis on 12 other liver function tests. K.ICG was strongly related to platelet count, circulatory blood volume, and albumin, all factors relating to portal hypertension. Rmax largely depended on LCAT, A/G ratio, and cholinesterase, which are Therefore, the dissociation between K.ICG and Rmax was caused by differences in the characteristic of each disease.

Cholestasis↗

[Smoldering leukemia with pyoderma gangrenosum].

A 76-year-old male admitted to Surugadai Nihon University hospital complaining of general fatigue, slight fever and anorexia. The laboratory examination revealed anemia and an appearance of a few myeloblasts and 7% of monocytes in the peripheral blood. The nucleated cell count was 2 x 10(4)/microliters with 43% myeloblasts in the bone marrow aspirate. He was diagnosed as acute myelomonocytic leukemia. He did not receive any chemotherapy for leukemia because of his old age and smoldering disease. Pyoderma gangrenosum developed in the left submandibular and axillary regions about 6 months later. Three more month later, significant increase of myeloblast was recognized in the peripheral blood and the bone marrow. It has been reported that pyoderma gangrenosum precedes a remarkable increase of leukemic cells in the patients with acute leukemia in complete remission and with myelodysplastic syndrome. In our case, to, the same process was strongly suggested.

Aged↗