Search PubMed⌕ Search

Biomedical subjects

K Katagiri

Publications and source records attributed to K Katagiri.

At least 73 records · Page 4Linked to original sources
PubMed1994

The distribution of T-cell subsets among HTLV-I carriers in Japan.

Data on T-cell subsets from 89 human T-cell lymphotropic virus-I (HTLV-I) carriers and 25 seronegative people were analyzed to identify differences in T-cell subset values among three subgroups: HTLV-I carriers with abnormal lymphocytes (Ably; n = 24), carriers without Ably (n = 65), and HTLV-I seronegatives (n = 25). Estimates of mean values were adjusted for age, sex, smoking, and alcohol drinking, as appropriate. The percentage of CD25+ T cells was elevated in carriers with Ably (mean, 16.7 +/- 1.0) compared with the seronegatives (11.4 +/- 1.4; p = 0.0002); individuals with CD25 T-cell percentages above the median for the seronegatives had a corresponding 5.4-fold risk for being a carrier with Ably. Similarly, the percentage of CD4 T cells was elevated in carriers with Ably. Conversely, the percentage of CD8 T cells was lower among both groups of HTLV-I carriers than in the seronegatives. There was a corresponding significant increase (p = 0.0004) of the CD4/CD8 ratio among carriers with Ably (1.57 +/- 0.12) compared with the seronegatives (1.22 +/- 0.12). Among subjects with CD4/CD8 ratios above the median for the seronegatives, there were 6.8- and 4.5-fold risks for being carriers with or without Ably, respectively. The percentage of CD7 was lower among carriers with Ably (75.6 +/- 1.6) than among seronegatives (78.9 +/- 1.5; p = 0.13). The percentage of beta-interleukin-2-receptor-positive T cells did not vary among the three subgroups.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗
PubMed1993

Tyrosine-phosphorylation of tubulin during monocytic differentiation of HL-60 cells.

We have demonstrated that the 53- and 55-kDa proteins were markedly phosphorylated at tyrosine residues during tetradecanoyl phorbol acetate (TPA)-induced monocytic differentiation of HL-60 cells and that the inhibition of such phosphorylation resulted in suppression of the differentiation. Western blotting, using antiphosphotyrosine antibody PY-20, of antitubulin immunoprecipitate from the lysate of TPA-treated HL-60 cells revealed that tubulin was tyrosine-phosphorylated in TPA-treated HL-60 cells, but not in nontreated HL-60 cells. The tyrosine-phosphorylated 53- and 55-kDa proteins in TPA-treated HL-60 cells were absorbed with antitubulin antibody indicating that the predominantly tyrosine-phosphorylated proteins during the monocytic differentiation were tubulins. By combination of immunoprecipitation and in vitro kinase assay, the protein tyrosine kinases, Fyn and Lyn, which were abundantly induced during monocytic differentiation of HL-60 cells, were demonstrated to be associated with tubulin in the cells. The reorganization of microtubules was observed by immunostaining using rhodamine-conjugated anti-mouse Ig and mouse anti-alpha-tubulin mAb. These data suggest that tyrosine-phosphorylation of tubulin, in which Fyn and Lyn might involve, regulate monocytic differentiation through alteration of microtubule assembly.

Cell Differentiation↗
PubMed1993

Effects of dibutyryl cyclic AMP and papaverine on intrahepatocytic bile acid transport. Role of vesicle transport.

The secondary messenger cyclic AMP plays an important role in regulating biliary excretory function by stimulating the transcytotic vesicle transport system, whereas papaverine exerts an inhibitory effect on this system. We therefore investigated their effects on bile acid-induced cytotoxicity and intrahepatocytic content of bile acid in primary cultured rat hepatocytes. Simultaneous addition of 1 mM dibutyryl cyclic AMP (DBcAMP), an analogue of cAMP, with 1 mM taurochenodeoxycholic acid (TCDCA) significantly decreased the release of lactate dehydrogenase (LDH) as compared with the case with 1 mM TCDCA alone (7.1 +/- 0.13% of total versus 10.7 +/- 0.3%). In contrast, 0.1 mM papaverine approximately doubled the amount of LDH (22.0 +/- 0.6% of total versus 10.7 +/- 0.3%; P < 0.01). The intracellular content of TCDCA 180 min after the administration of 1 mM TCDCA alone was 20.8 +/- 0.7 nmol/mg protein, that after simultaneous administration of 1 mM DBcAMP, 16.2 +/- 1.0 nmol/mg protein, and that after the simultaneous administration of 0.1 mM papaverine, 38.5 +/- 1.9 nmol/mg protein. A clear correlation between the release of LDH from hepatocytes and the intracellular content of TCDCA was thus observed. When given together with 1 mM taurocholic acid (TCA) or 1 mM tauroursodeoxycholic acid (TUDCA), papaverine exerted little effect on cytotoxicity or intrahepatocytic bile acid content. When cells were bathed in a medium free of bile acid after pretreatment with 1 mM TCDCA and 1 mM DBcAMP, additional exposure to DBcAMP for 30 min significantly stimulated reduction of intracellular TCDCA content (30.2 +/- 0.4% of total versus 44.0 +/- 1.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Tauroursodeoxycholate and tauro-beta-muricholate exert cytoprotection by reducing intrahepatocyte taurochenodeoxycholate content.

Cytoprotection by tauroursodeoxycholic acid and tauro-beta-muricholic acid against taurochenodeoxycholic acid-induced toxicity was examined with reference to intracellular bile acid content in primary cultured rat hepatocytes. In comparison with levels in the group administered taurochenodeoxycholic acid 1 mmol/L alone, lactate dehydrogenase levels in the culture medium decreased significantly in groups simultaneously administered taurochenodeoxycholic acid 1 mmol/L and tauroursodeoxycholic acid 0.5 to 2 mmol/L or tauro-beta-muricholic acid. Results of the trypan blue uptake test indicated that the lactate dehydrogenase release was indeed caused by cell damage. After the administration of tauroursodeoxycholic acid 2 mmol/L or tauro-beta-muricholic acid 2 mmol/L, intracellular taurochenodeoxycholic acid content was consistently reduced to half of that after administration of taurochenodeoxycholic acid alone. Simultaneous administration of dibutyl cyclic AMP also reduced intracellular taurochenodeoxycholic acid content and lactate dehydrogenase release. Being rinsed with tauroursodeoxycholic acid and tauro-beta-muricholic acid after being precultured in taurochenodeoxycholic acid 1 mmol/L also markedly reduced their taurochenodeoxycholic acid content. Taurocholic acid caused limited reduction of intracellular taurochenodeoxycholic acid but not suppression of lactate dehydrogenase release. Taurodehydrocholic acid showed no reduction of taurochenodeoxycholic acid content and no decrease of lactate dehydrogenase release. Although only small amounts of tauroursodeoxycholic acid or tauro-beta-muricholic acid were found to accumulate in hepatocytes, taurocholic acid increased as if replacing taurochenodeoxycholic acid. The results suggest that tauroursodeoxycholic acid or tauro-beta-muricholic acid may exert cytoprotective effects by lowering intracellular taurochenodeoxycholic acid levels associated with their optimal hydrophilicity.

Animals↗
PubMed1992

Microtubule-independent choleresis and anti-cholestatic action of tauroursodeoxycholate in colchicine-treated rat liver.

In order to cast light on the anti-cholestatic and cytoprotective properties of ursodeoxycholic acid (UDCA), intrahepatic transport and secretion of bile salts and biliary phospholipids were investigated by using isolated perfused livers from colchicine-pretreated rats. Administration of taurocholic acid (TCA) after colchicine pretreatment induced marked cholestasis. Tauroursodeoxycholic acid (TUDCA) treatment, in contrast, was associated with maintenance of bile flow, with excretion rates of bile acids and phospholipids similar to those in control animals. Furthermore, TCA-induced cholestasis in colchicine-treated rat livers was clearly decreased by co-administration of TUDCA. Although simultaneous addition of UDCA also showed slight improvement, with or without taurine pre-treatment, biliary bile-salt analysis also showed that cholestasis was markedly remitted as the excretion of taurine-conjugated UDCA was increased. The results suggest that the cytoprotective and anti-cholestatic effects of TUDCA may be linked to action at the intrahepatocyte level, represented by mild detergent effects on organelle lipids and preservation of intracellular transport even under microtubule-dysfunctional conditions. In addition, it was indicated that cytoprotective effects of UDCA may also be exerted after its conjugation with taurine inside hepatocytes.

Animals↗
PubMed1992

Papaverine inhibits transcytotic vesicle transport and lipid excretion into bile in isolated perfused rat liver.

Papaverine is a nonspecific smooth muscle relaxant and a phosphodiesterase inhibitor. Its effects on biliary excretion of lipids and horseradish peroxidase were investigated in a single-pass isolated perfused rat liver model. A constant infusion of papaverine (1.6 mumol/min; 40 mumol/L) significantly increased bile flow (microliters per minute per gram of liver) before (2.03 +/- 0.09 vs. 1.0 +/- 0.06) and after sodium taurocholate infusion (2.77 +/- 0.10 vs. 1.88 +/- 0.11). However, papaverine significantly and reversibly reduced biliary excretion of phospholipids and cholesterol (nanomoles per minute per gram of liver) after a 1.0 mumol/min sodium taurocholate infusion, from 7.45 +/- 0.83 and 1.42 +/- 0.15 to 1.75 +/- 0.18 and 0.39 +/- 0.06, respectively (p less than 0.01), whereas secretion of bile acids was unaffected. When a 1-min pulse of horseradish peroxidase (25 mg) was infused in isolated perfused rat liver after a continuous infusion of N6,O-2'-dibutyryladenosine 3',5'-cyclic monophosphate (0.25 mumol/min; 6.25 mumol/L), horseradish peroxidase appeared in bile in an early (4 to 6 min) and late (20 to 25 min) peak. Papaverine significantly reduced the late peak, from 1.211 +/- 0.264 to 0.498 +/- 0.107 (p less than 0.01). Papaverine had no significant effects on either cyclic AMP or cyclic GMP in the liver and bile, although it has been reported that papaverine is a phosphodiesterase inhibitor. These findings indicate that papaverine inhibits biliary excretion of lipids but not bile acids, and they suggest that papaverine has an inhibitory effect on transcytotic vesicle transport independent of an increase of cyclic nucleotides in hepatocytes.

Animals↗
PubMed1992

Single- and multiple-dose pharmacokinetics of intravenous cefpirome (HR810) to healthy volunteers.

The safety and pharmacokinetics of single and multiple administrations of cefpirome (HR810), a new cephalosporin antibiotic agent with a broad antibacterial spectrum, were studied in healthy male volunteers. The single administration protocols included a 3-minute intravenous injection of 0.5 g or 1 g, and a 1-hour intravenous drip infusion of 0.5 g, 1 g, or 2 g. The multiple administration protocols included nine intravenous injections and 1-hour intravenous drip infusions of 1 g of cefpirome twice a day at intervals of 12 hours. Cefpirome was tolerated, and only a few mild, subjective and hepatic-function side effects were observed. There were no severe abnormalities. The drug concentrations in the plasma and the urine were determined by means of HPLC and bioassay, and the results correlated well (r = 0.99). The pharmacokinetic parameters were calculated using a two-compartment model. The elimination half-life (t1/2 beta) was about 1.7 hours for both intravenous injection and intravenous drip infusion and was not dose-dependent. AUC and Cmax were dose-dependent in this study, although an accumulation due to multiple administrations was not observed, and there were no changes in the pharmacokinetic parameters after the initial and the final administrations. The recovery rate of the unchanged compound in the urine was more than 80% in the 24 hours after a single administration and was the same after multiple administrations. Bioautography did not show any active metabolites in the plasma or the urine. The results, for safety and pharmacokinetics, show that cefpirome can be expected to have excellent clinical efficacy for bacterial infections.

Adult↗
PubMed1992

Modulation of monocytic differentiation of HL-60 cells by inhibitors of protein tyrosine kinases.

We showed previously that the expressions of various src family protein tyrosine kinases (PTKs) were induced independently during the monocytic differentiation of HL-60 cells. The role of PTKs was further assessed in the present study by investigating the effects of PTK inhibitors on the differentiation. It was demonstrated that PTK inhibitors such as genistein and herbimycin A modulated monocytic differentiation of HL-60 cells; they inhibited the differentiation induced by TPA, while promoting that induced by vitamin D3 (D3). Immunoblotting analysis of protein molecules which had been phosphorylated on their tyrosine residues demonstrated that TPA induced phosphorylation of certain molecules different from those induced by D3 in HL-60 cells. PTK inhibitors blocked the phosphorylation and modulated differentiation driven by the inducers. These data suggest that PTKs are involved both promotively and suppressively in signaling events that induce monocytic differentiation of HL-60 cells.

Antibiotics, Antineoplastic↗
PubMed1992

Tauro-beta-muricholate preserves choleresis and prevents taurocholate-induced cholestasis in colchicine-treated rat liver.

In recent clinical and animal experimental studies, ursodeoxycholic acid (UDCA) has been noted to have marked choleretic and cytoprotective actions. To define the mechanism and determine whether such favorable influence is specific to UDCA, the choleretic action of beta-muricholic acid (beta-MCA), which has a similar chemical structure, was studied using an isolated rat-liver-perfusion system. As a result, beta-MCA and taurine-conjugated beta-MCA (T beta-MCA) stimulated bile flow accompanied by elevation of bile acid output and phospholipid output, and beta-MCA caused an elevation in biliary HCO3- concentration in normal rat livers. After colchicine treatment, taurocholic acid (TCA) administration was associated with marked cholestasis while both beta-MCA and T beta-MCA still increased bile flow under the same conditions. Furthermore, simultaneous administration of beta-MCA or, more markedly, T beta-MCA reversed the effects of TCA alone in colchicine-treated rat liver; significant preventive effects against the cholestasis could be shown. These data suggest that beta-MCA and especially T beta-MCA can support choleresis even under conditions of colchicine-dependent microtubule dysfunction. The effects of T beta-MCA on organelle lipids and their intracellular transport may differ from those of TCA, presumably because of the anticholestatic and cytoprotective effects of T beta-MCA.

Animals↗
PubMed1992

Evaluation of duodenal papillary function by ERCP-CT and comparison with endoscopic measurement of pressure in the papillary sphincter zone.

Imaging of the main pancreatic duct on ERCP-CT (computerized tomography performed immediately after endoscopic retrograde cholangiopancreatography) was evaluated in 192 patients. Favorable images were obtained in elderly patients, as well as in those with main pancreatic duct dilation, chronic pancreatitis, papillary disease, and choledocholithiasis. In addition, we used a microtransducer inserted through a duodenoscope to measure papillary sphincter zone and main pancreatic duct pressure. We then compared the endoscopic results with the images achieved on ERCP-CT. The patients with favorable images showed higher pancreatic and papillary basal pressure and a faster wave cycle than those with poor images. In addition, significant differences in pancreatic duct pressure and basal pressure were seen. Peak papillary pressure showed no consistent correlations with imaging. Patients with favorable images exhibited an increase in the frequency of irregular papillary sphincter zone waves. We conclude from these findings that good images on ERCP-CT reflect a slow flow of pancreatic juice, which is closely associated with papillary stenosis.

Aging↗
PubMed1992

[STA-ACA anastomosis with interposed vein graft; a case report].

We report our experience with the use of three saphenous vein grafts for treating advanced occlusive cerebrovascular disease in the anterior cerebral artery (ACA) in two patients. Superficial temporal artery (STA)-ACA anastomosis with interposed vein graft is thought to be indicated for patients who have STA of insufficient length to anastomose to the ACA. Vein graft has already been demonstrated to be applicable in extracranial-intracranial artery bypass, as well as in aorto-coronary bypass. Two factors considered to be essential for successful revascularization are technical proficiency, including protection from drying, smooth approximation of vessels, and proper orientation of the graft, and the relative size of donor and recipient vessels. Because the vein graft must be anastomosed with the proximal ACA to reduce the size discrepancy between vessels, prolonged interruption of circulation during suturing is inevitable. Our operative results suggest that anastomosis to a superficial branch of the ACA just distal to the interhemispheric fissure seems to be preferable to anastomosis using vein graft, and we recommend the option of vein graft only when the STA cannot be used.

Anastomosis, Surgical↗
PubMed1991

An intrinsic B cell defect is required for the production of autoantibodies in the lpr model of murine systemic autoimmunity.

Mice homozygous for the gene lpr develop marked lymphadenopathy and a spectrum of autoantibodies closely resembling that of human systemic lupus erythematosus. The unusual T cell phenotype of the expanded lymphocyte population and the T-dependence of several antibodies in this strain have suggested that primary T cell abnormalities underlie the autoimmune syndrome. Using double chimeras, we now show that expression of the lpr gene in B cells is absolutely necessary for autoantibody production. Combinations of anti-Thy 1.2 + C' treated bone marrow from congenic strains of C57BL/6 mice, differing only at the immunoglobulin heavy chain (Igh) and lpr loci, were transferred into lethally irradiated B6/lpr mice. Double chimerism was documented by allotype-specific surface IgD and IgM immunofluorescence assay of peripheral blood and by allotype-specific enzyme-linked immunosorbent assay for total IgM in serum. Despite the presence of both +/+ and lpr B cells, IgM and IgG2a anti-chromatin as well as IgM anti-IgG were entirely the products of lpr B cells. Total serum IgG2a and IgG1 were also dominated by the lpr phenotype but not to the same extent. A similar experiment using B6/lpr-Igha recipients confirmed these findings. Additional experiments in which B6/lpr recipients were infused with ratios of donor bone marrow favoring B6.C20 +/+ over B6/lpr showed that even though +/+ B cells were overrepresented, autoantibodies were only of the lpr allotype. In addition, in the presence of lpr B cells, normal B cells showed little response to an exogenous, T cell-dependent antigen. The data thus indicate that lpr B cells manifest an intrinsic abnormality which is essential for autoantibody production in the lpr model.

Animals↗
PubMed1991

Expression of src family genes during monocytic differentiation of HL-60 cells.

It has been reported that src family protein-tyrosine kinases were expressed specifically in a certain lineage or differentiation stage of hematopoietic cells. To understand the molecular basis for differentiation and function of monocyte/macrophage, we investigated the expressions of src family genes by the HL-60 cells stimulated with differentiation-inducing agents. TPA and vitamin D3 (D3) were used as stimulants for monocytic development, since each agent has been known to induce phenotypically specific differentiation of HL-60 cells. The fyn, fgr, and lyn genes were characteristically expressed concomitantly with phenotypic changes and expressions of nuclear proto-oncogenes, whereas src, lck, hck, and yes genes were not. In TPA-induced differentiation of HL-60 cells, both fyn and lyn genes, but not fgr gene, were expressed. In contrast, both fgr and lyn genes, but not fyn gene, were expressed in D3-induced differentiation of the cells. The independent and characteristic expressions of these genes were observed in the further advanced differentiation of HL-60 cells induced by TPA plus D3 or D3 plus human transforming growth factor-beta 1. The granulocytic differentiation of the cells treated with retinoic acid was accompanied by intense expression of fgr, but weak or no expression of lyn and fyn gene. These data indicate that each protein-tyrosine kinase encoded by src family genes may play distinct roles in development and/or functions of monocyte/macrophage-lineage cells.

Calcitriol↗
PubMed1991

Study on suspended particulate matter and polycyclic aromatic hydrocarbons in indoor and outdoor air.

To study changes in the concentration of suspended particulate matter (SPM) in indoor and outdoor air, a new portable sampler (AND sampler) was designed that could separately collect particles exhibiting aerodynamic diameters of greater than 10 microns, 2-10 microns, and less than 2 microns. The relationship between the airborne particle concentration in indoor air and that in outdoor air varied with the aerodynamic diameter of the particles. The concentration of SPM in the indoor air increased in proportion to that in the outdoor air. The concentration of polycyclic aromatic hydrocarbons (PAH) in SPM also varied with the aerodynamic diameter of the particles. Fine particles exhibiting an aerodynamic diameter of less than 2 microns contained high concentration of PAH. The concentrations of benzo(k)fluoranthene, benzo(a)pyrene, and benzo(ghi)perylene in indoor air increased in proportion to those in outdoor air.

Air Pollutants↗
PubMed1991

Heterogeneity of clinical features of pseudoxanthoma elasticum: analysis of thirteen cases in Oita Prefecture from a population of 1,240,000.

Thirteen cases among 16,260 patients seen at our department during the nine years from 1981 were diagnosed as pseudoxanthoma elasticum (PXE). The sex and age distributions were similar to those so far reported in the literature. There were two cases of the autosomal dominant type. One patient had skin lesions typical of PXE in association with Ehlers-Danlos syndrome. In two of three patients with cutis laxa-like lesions, eruptions of elastosis perforans serpiginosa were present. In three cases, we failed to detect deposition of calcium in typical skin lesions in either an early or a late stage by histochemical staining, in spite of the presence of slightly degenerated elastic fibers.

Adolescent↗
PubMed1991

[Malignant fibrous histiocytoma of the heart--a case report and review of the literature].

Malignant fibrous histiocytoma (MFH) has been rarely reported as a primary tumor of the heart. We present a case of a primary intracardiac MFH and review the 28 previous reports of this rare cardiac tumor. A 48-year-old woman underwent an operation for congestive heart failure (CHF) due to a left atrial tumor. A large multinodular tumor attached to the posterior wall of the left atrium and extended into the mitral annulus and the posterior leaflet of the mitral valve. The tumor was resected incompletely and mitral valve replacement was performed. Pathological diagnosis was MFH. The patient did well in the postoperative period, but she again presented with symptoms of CHF four months later. Chest CT and two-dimensional echocardiogram demonstrated a recurrent tumor of the left atrium. Since the tumor grew rapidly despite chemotherapy, a reoperation was performed to remove it. Nevertheless, as the tumor was found to have extended into the pericardial cavity and posterior mediastinum, only partial resection was possible. After a protracted operation, the heart failed to sustain the circulation and the patient died. The prognosis of intracardiac MFH was poor in spite of surgery, radiation and/or chemotherapy. However, repeated surgical treatments can relieve symptoms of CHF and may prolong the life of patients.

Female↗
PubMed1990

CCA (disodium 4-chloro-2,2'-iminodibenzoate) inhibits progression of human T cell proliferation triggered by PHA.

The effect of the anti-rheumatic drug CCA (disodium 4-chloro-2,2'-iminodibenzoate) on the proliferation of T cells activated by PHA was examined. Cell cycle analysis showed that CCA blocked the transition of the cells from G1 to S (progression), but had little effect on the G0----G1 transition (initiation). CCA had no significant effect on IL-2 receptor expression, an early G1 event, but did inhibit transferrin receptor expression, a late G1 event. CCA did not inhibit IL-2 production by PHA-activated T cells, but did block IFN-gamma production at 72 hr after the stimulation. CCA failed to inhibit c-myc mRNA induction, but did delay the decrease in c-myc mRNA levels that normally occurs with the onset of DNA synthesis. These results indicate that CCA inhibits the progression, but not initiation, of human T cell proliferation.

Cell Cycle↗