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Biomedical subjects

K Tsuji

Publications and source records attributed to K Tsuji.

At least 487 records · Page 27Linked to original sources
PubMed1991

Study on the bile salt, sodium scymnol sulfate, from Rhizoprionodon acutus. II. The structures of scymnol, anhydroscymnol and sodium scymnol sulfate.

The crystal structures of anhydroscymnol (I) and scymnol (II), which were prepared from sodium scymnol sulfate (III) isolated from the bile of Rhizoprionodon acutus, have been determined by means of X-ray diffraction analyses. The crystals of I are orthorhombic, space group P2(1)2(1)2(1) with Z = 4; unit-cell dimensions: a = 13.562(2), b = 21.636(2), c = 8.735(2) A; II orthorhombic, space group P2(1)2(1)2, with Z = 4; unit-cell dimensions a = 18.553(2), b = 19.887(2), c = 7.986(2) A. Both structures, (24R,25S)-(+)-24,26-epoxy-5 beta-cholestane-3 alpha,7 alpha,12 alpha,27-tetrol (I) and (24R)-(+)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26,27-hexol (II), were solved from diffractometric data by direct methods and refined by least-squares calculations to R = 0.073 (I) and R = 0.062 (II) (2044 (I) and 2250 (II) observed independent significant reflections (I greater than 3 sigma(I)), respectively. All the hydroxyl groups of both compounds are involved in a hydrogen-bonding network. The structure of III was determined to be (24R,25S)-(+)-3 alpha,7 alpha,12 alpha,24,26-pentahydroxy-5 beta-cholestan-27-yl sodium sulfate, based on the chemical data that alkaline degradation of III with aqueous potassium hydroxide gives only I.

Bile Acids and Salts↗
PubMed1991

Isolation and structural determination of a mutagenic substance in creatine pyrolysate.

The pyrolysis product of creatine showed potent mutagenic activity to Salmonella typhimurium TA98 with metabolic activation by S9 mix. One of the mutagenic substances in creatine pyrolysate was isolated and named Cre-P-1. Its structure was determined by X-ray crystallography to be 4-amino-1,6-dimethyl-2-methylamino-1H,6H-pyrrolo[3,4-f]benzimidazole- 5,7-dione. Cre-P-1 is the first registered mutagenic heterocyclic amine containing oxygen atoms in the molecule, that has been isolated from pyrolysis products.

Animals↗
PubMed1991

Autokinetic illusion as affected by suggestions of experimenter and observer.

Two experiments were done to examine whether an experimenter's suggestion and self-suggestion could affect the autokinetic illusion and to specify that effect. Exp. I compared the effect of a facilitative suggestion with a suppressive one, by measuring the moving latency, duration, frequency, and by analyzing the movement trace. Time and frequency did not detect any effects of marked individual differences. Trace analysis, on the other hand, showed that suggestions were effective in the expected direction for some subjects. Exp. II gave the suggestion for and against subjects' dominant direction of the movement and was designed to specify the effect. While effects indicated by time and frequency measures were not consistent, the movement trace showed the effect in suggested directions, which was more distinct for subjects whose nonsuggested illusion was not so markedly directed. These findings indicate that suggestion could affect the spatiotemporal aspect of the illusion, so the trace analysis may be useful for studies in this field.

Adult↗
PubMed1991

Utilization and metabolism of [U-14C]4' galactosyllactose (O-beta-D-galactopyranosyl-(1----4)-O-beta-D-galactopyranosyl-(1----4)- D-glucopyranose) in rats.

O-beta-D-Galactopyranosyl-(1----4)-O-beta-D-galactopyranosyl- (1----4)-D-glucopyranose (designated as 4'GL) are produced from lactose with Cryptococcus laurentii OKN-4. Excretion and metabolism of 4'GL in rats were examined using a radioisotope technique. [U-14c]4'GL was synthesized from [U-14C]lactose by Cryptococcus laurentii OKN-4. The 14CO2 in expired air was counted after oral administration of [U-14C]4'GL or [U-14C]lactose in conventional rats, rats treated with antibiotics and germ-free rats. The rate of 14CO2 excretion from conventional rats given [U-14C]4'GL was slower than that from those administered [U-14C]lactose. When [U-14C]4'GL was orally administered to rats given antibiotics, there was a 2-h delay in 14CO2 excretion, as compared to conventional rats. In germ-free rats, total excretion of 14CO2 from [U-14C]-4'GL decreased to about one-third of that of conventional rats during a 24-h period. Radioactivities in the serum, liver, and carcass of the [U-14C]4'GL oral administration group were lower than those of the [U-14C]lactose oral administration group. Radioactivities in the feces and urine however, were higher in [U-14C]4'GL group than in [U-14C]lactose group.

Animals↗
PubMed1991

Trimethadione tolerance test for one-point estimation of the severity of liver damage in cirrhotic patients.

We evaluated the adequacy of the trimethadione (TMO) tolerance test (the method of estimation from the serum dimethadione [DMO]/TMO ratio, DMO is only one metabolite of TMO, at 4 hours after oral administration of TMO) for estimating the severity of liver damage in 40 cirrhotic patients with and without hepatic encephalopathy. Serum dimethadione (DMO)/TMO ratios in a single blood sample after oral administration of TMO were significantly lower in cirrhotic patients with (0.07 +/- 0.02, p less than 0.05) or without (0.29 +/- 0.12, p less than 0.05) hepatic encephalopathy than in normal subjects (0.63 +/- 0.04). Serum DMO/TMO rations showed a good correlation with the following laboratory data: plasma indocyanine green retention at 15 minutes (r = -0.857, p less than 0.001), serum choline-esterase activity (r = 0.844, p less than 0.001), and albumin (r = 0.736, p less than 0.001). In cirrhotic patients with hepatic encephalopathy, the serum DMO/TMO ratio was found to be below 0.10, which was 16% of the normal level, by the TMO tolerance test. These findings suggest that the TMO tolerance test is a useful indicator of the hepatic parenchymal function in cirrhotic patients.

Dimethadione↗
PubMed1991

Aflatoxin B1-DNA binding and aflatoxin B1-glutathione conjugation with isolated hepatocytes from rats and hamsters.

Binding of aflatoxin B1 (AFB1) to DNA and AFB1-glutathione conjugation during the metabolism of AFB1 have been examined with freshly isolated hepatocytes from male Fischer rats and Syrian hamsters. Even though there was no significant difference in cytochrome P450 and glutathione contents, there were marked differences in the metabolism of AFB1 (33 nM) in hepatocytes from these two species. Thus, AFB1-DNA binding was six-fold higher in the rat than in hamster hepatocytes, whereas AFB1-glutathione conjugation was 12-fold higher in hamster than in rat hepatocytes. The addition of 0.5 mM diethylmaleate had no significant effect in rats, whereas its presence produced a nine-fold increase in AFB1-DNA binding with 85% inhibition of thiol conjugation in hamster hepatocytes. Styrene oxide (1 mM) produced 50% and 25-fold increases in AFB1-DNA binding in rat and hamster hepatocytes, respectively, with corresponding decreases in thiol conjugation. Triethyltin bromide (50 microM) inhibited both processes by 50% in rat hepatocytes, whereas it produced a nine-fold increase in AFB1-DNA binding with a concomitant decrease in thiol conjugation in hamster hepatocytes. These results suggest that glutathione S-transferases play a more significant role in modulating AFB1-DNA binding in hamster than in rat hepatocytes.

Aflatoxin B1↗
PubMed1991

[A case of type B chronic hepatitis showing rapid progression to liver cirrhosis with prolonged positive IgM anti-HBc].

We reported a case of type B chronic hepatitis with high titer of IgM anti-HBc continuously, which progressed to liver cirrhosis rapidly. The patient was a 37-years-old man, and was diagnosed as chronic type B hepatitis with severe activity by laparoscopy and liver biopsy. The titer of IgM anti-HBc persisted high level for more than 2 years. Then the second liver biopsy showed the progression to liver cirrhosis within only about 2 years. It is a very rare case to prolong positive IgM anti-HBc for such a long time. Anti-HBc production of PBMC was enhanced remarkably in this case. We considered that HBc antigens released into serum from hepatocytes with severe exacerbations had enhanced the anti-HBc producing activity of B lymphocytes. And the rapid progression in this case would be due to the episodes of severe exacerbations.

Adult↗
PubMed1991

Phlegmonous enteritis in alcoholic fatty liver.

Phlegmonous enteritis is a rare inflammatory bowel disease. A 52-yr-old man with a history of alcoholic abuse was admitted to the hospital for an acute abdomen and died of septicemia and its complications. Autopsy revealed phlegmonous inflammation of the ileum and severe fatty liver. Numerous Gram-negative rod bacilli were demonstrated in the ileal mucosa. Shortened villi and decreased lysozyme activity of Paneth cells in the small intestine might be results of chronic alcohol ingestion. The relationship between phlegmonous enteritis and alcoholic abuse was strongly suggested in this case.

Alcoholism↗
PubMed1991

[Immunogenetic mechanism of Behçet's disease].

In order to investigate the immunogenetic mechanism of Behçet's disease, frequencies of HLA antigens were studied in patients. The subjects consisted of 66 patients and 99 normal controls. A lymphocyte cytotoxicity test was used for typing HLA-A, -B, -C, -DR, -DQ antigens. HLA-DP antigens were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. A significant increase of HLA-B15 was observed in the patients. In contrast, no significant difference was observed in HLA-Bw52 which possesses only two different amino acids from HLA-B15. On the contrary, frequencies of HLA-A11, HLA-Aw33, HLA-B35, HLA-B44 and HLA-DQw1 were significantly lower in the patients than in the controls. No significant difference was observed in HLA-DP antigens. These results suggest that Behçet's disease involves both disease susceptibility factors and disease resistance factors and that such genetic factors are mapped within or very close to the HLA-B gene in the class I gene region. Additionally class II HLA-DQ antigen is associated with disease resistance factors.

Amino Acid Sequence↗
PubMed1991

Effect of structural modification of several groups on the D-ring of grayanotoxin on its depolarization potency in squid giant axon.

The purpose of this investigation was twofold, 1) to clarify the pharmacological significance of various groups on the D-ring of grayanotoxin (GTX) and 2) to determine possible sites on GTX which are available for preparing pharmacological probes. All GTX derivatives were directly applied to the intracellular phase of internally perfused squid giant axons. A dose-response curve for each GTX analog was constructed using depolarization as an index and assuming a simple one-to-one stoichiometry. By comparing EC50 and the maximum depolarization caused by GTX analogs, the main factors affecting potency were found to be: the formation of 1) electrostatic interaction, 2) a hydrogen bond between groups on the D-ring of GTX and part of the Na channel protein and 3) balance between hydrophilicity and hydrophobicity in the GTX molecule. Biologically essential groups like those in the A- and B-rings were not recognized. A suitable site on GTX for synthesizing pharmacological probes is probably position C-17 of grayanotox-15-ene compound, because in chemical modification, bulkier groups can be introduced without a total loss of biological activity of GTX. Another possible site for modification is position C-14R, because this portion is on the molecular surface opposite biologically essential groups. It can be speculated that in GTX binding, possible molecular moiety of the Na channel facing the D-ring of GTX is rich in positively charged amino groups.

Animals↗
PubMed1990

Interleukin-6 enhances murine megakaryocytopoiesis in serum-free culture.

We investigated the effect of interleukin-6 (IL-6) on murine megakaryocytopoiesis in a serum-free culture system. The addition of IL-6 to a culture containing interleukin-3 (IL-3) resulted in a significant increase in the number of megakaryocyte colonies by bone marrow cells of normal mice. The megakaryocytic progenitors that survive exposure to 5-fluorouracil (5-FU) exhibited a more significant response to IL-6 and IL-3. Polyclonal anti-IL-6 antibody neutralized the stimulatory effect of IL-6 on megakaryocyte colony growth supported by IL-3. Delayed addition experiments and replating experiments of blast cell colonies showed that megakaryocytic progenitors are supported by IL-3 in the early stage of the development but require IL-6 for their subsequent proliferation and differentiation. In addition, IL-6 increased the size of megakaryocytes in granulocyte-macrophage-megakaryocyte colonies. The combination of granulocyte colony-stimulating factor or granulocyte-macrophage colony stimulating factor with IL-3 resulted in an increase in the granulocyte-macrophage colony growth of bone marrow cells of 5-FU-treated mice or normal mice, respectively, but had little effect on the enhancement of pure and mixed megakaryocyte colony growth. These results suggest that IL-6 plays an important role in murine megakaryocytopoiesis.

Animals↗
PubMed1990

Localization of specificity determining sites in cadherin cell adhesion molecules.

Cadherins are a group of homophilic intercellular adhesion molecules; each member of this family exhibits binding specificity. Here, we attempted to map the sites for the specificities of these molecules by analyzing adhesives selectivities of the cells that express chimeric and point-mutated E- and P-cadherin. The results showed that the amino-terminal 113 amino acid region is essential to determine the specificities, and within this region we could identify especially important sites in which amino acid substitutions altered the binding specificity of cadherins. We also found that the epitopes for antibodies capable of blocking cadherin action are located in this amino-terminal region.

Amino Acid Sequence↗
PubMed1990

Studies on transfer of varicella-zoster-virus specific T-cell immunity from bone marrow donor to recipient.

The transfer of antigen-specific cellular immunity in human bone marrow transplantation (BMT) was studied in 49 donor-recipient pairs, using a varicella-zoster-virus (VZV) specific lymphoproliferative response (LPR) assay. Posttransplant VZV-LPR could be serially measured in 31 long-term surviving recipients. VZV-specific T-cell immunity was detected in the early posttransplant period in 4 of 16 recipients who were, and whose donors were, immune to VZV before BMT, but two of those positive responses diminished in the first 100 days posttransplant. No positive response was detected in the immediate posttransplant period when either only the recipient or the donor was immune to VZV pretransplant. Herpes zoster or chickenpox developed in the recipients depending on a history of pretransplant VZV infection when the VZV-LPR became negative, and recovery from VZV infection was always followed by quick conversion of VZV-LPR. Long-lasting positive VZV-LPR was observed in the two recipients who experienced VZV infection in the immediate pretransplant period and received marrow graft from an immune donor. Our results indicate that a simple or direct transfer of VZV-specific cellular immunity from a marrow donor to a recipient cannot be expected in usual clinical bone marrow transplantation and that there might be a collaboration or recruitment of immune responses involving both donor and recipient that permits the VZV-LPR to remain positive posttransplant.

Bone Marrow Transplantation↗
PubMed1990

Effects of interleukin-3 and interleukin-4 on the development of "connective tissue-type" mast cells: interleukin-3 supports their survival and interleukin-4 triggers and supports their proliferation synergistically with interleukin-3.

We examined the effects of interleukin-3 (IL-3) and interleukin-4 (IL-4) on connective tissue-type mast cells (CTMC) purified from murine peritoneal cells. Although both factors failed to induce extensive proliferation of CTMC, they stimulated CTMC proliferation synergistically in a dose-dependent manner. Pretreatment of CTMC with IL-3 and/or IL-4 indicated that the sustained presence of both factors was required for the development of type 1 mast cell colonies. The delayed addition of IL-3 to cultures of purified CTMC with IL-4 induced no colony formation, while the delayed addition of IL-4 to cultures with IL-3, even on day 28 of culture, induced type 1 colony formation. In replating type 1 colonies induced by IL-3 and IL-4 to secondary cultures with IL-3 alone, few secondary colonies developed. However, the delayed addition of IL-4 to the secondary culture induced many type 1 colonies. The purified CTMC cultured with IL-3 retained the morphological and cytochemical characteristics of CTMC, as well as proliferative ability. These observations indicate that IL-3 supports the survival of CTMC in methylcellulose culture and that IL-4 triggers and supports CTMC proliferation synergistically with IL-3. The serum-free culture of purified CTMC and the culture of single CTMC demonstrated that the synergistic effect of IL-3 and IL-4 on colony growth and the surviving effect of IL-3 on CTMC require no influence from accessory cells or other humoral factors.

Animals↗
PubMed1990

Synergistic action of phorbol ester and IL-3 in the induction of "connective tissue-type" mast cell proliferation.

12-O-Tetradecanoylphorbol-13-acetate (TPA), a tumor-promoting phorbol ester, induced the proliferation of connective tissue-type mast cells (CTMC) synergistically with IL-3 in a methylcellulose culture, as well as with IL-4. The culture of single CTMC and the serum-free culture of CTMC fractionated by Percoll density gradient centrifugation showed that this synergistic action of IL-3 and TPA required no effects of accessory cells or other humoral factors. Although the populations of CTMC acted on by TPA and IL-4 seemed to be close to each other, the velocity of colony growth induced by the simultaneous stimulation of the combination of TPA and IL-4 was faster than that induced by either TPA or IL-4 in the presence of IL-3. In addition, the addition of anti-IL-4 antibody did not neutralize the effect of TPA on the proliferation of CTMC. These results suggest that TPA and IL-4 act on the proliferation of CTMC synergistically with IL-3 via a different pathway. Beside TPA, other phorbol derivatives capable of activating protein kinase C (PKC) induced the proliferation of CTMC synergistically with IL-3, but phorbol derivatives which were unable to activate PKC did not. These results indicate that the activation of PKC is involved in the process of TPA action on the proliferation of CTMC. Furthermore, the facts that 1-oleoyl-2-acetylglycerol, which activated membrane PKC transiently, and staurosporine, which has been reported to inhibit PKC, did not induce the proliferation of CTMC in the presence of IL-3 and that the effect of TPA was exhibited by the sustained stimulation suggest that the action of TPA on the proliferation of CTMC requires at least two steps. The first one is the primary activation of membrane PKC and the second one is the disappearance of PKC from the cells, "down-regulation."

Alkaloids↗
PubMed1990

Familial case of May-Hegglin anomaly associated with familial spastic paraplegia.

We report a family with May-Hegglin anomaly associated with familial spastic paraplegia. The propositus was a 39 year old male. His peripheral blood showed a Döhle-like inclusion bodies in WBC, giant platelets, and thrombocytopenia. He had been suffering from progressive gait disturbance of spastic paraplegia since 20 years old. He was in a state of chronic renal failure and showed sensory hearing impairment. His two children showed similar hematological abnormalities and spastic gait. As far as we know, this is the first case of May-Hegglin anomaly associated with familial spastic paraplegia in the literature.

Adolescent↗
PubMed1990

Loss of the 3p25.3 band is critical in the manifestation of del(3p) syndrome: karyotype-phenotype correlation in cases with deficiency of the distal portion of the short arm of chromosome 3.

Two patients with monosomy for the distal portion of the short arm of chromosome 3 are described. Chromosome analysis on prometaphase cells demonstrated a karyotype of 46,XX,del(3) (p25.3) in one patient and 46,XX,r(3)(p26.1q29) in the other. The former patient showed characteristic clinical manifestations of the 3p- syndrome, including growth failure, mental retardation, microcephaly with a flat occiput, triangular face, synophrys, blepharoptosis, hypertelorism, broad and flat nose, long philtrum, down-turned mouth, micrognathia, apparently lowset and malformed ears, fingers abnormalities, and deafness. The latter patient had a nonspecific phenotype with mental retardation, growth failure and microcephaly. Karyotype-phenotype comparisons in the present cases and 16 previously reported cases with deficiency of the distal portion of 3p suggests that deficiency of the 3p25.3 band is critical to produce the main clinical manifestations of the del(3p) syndrome.

Chromosome Deletion↗