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Biomedical subjects

T Katsuki

Publications and source records attributed to T Katsuki.

At least 163 records · Page 9Linked to original sources
PubMed1981

Mechanisms of enhancement of Epstein-Barr virus-induced transformation of peripheral blood lymphocytes by a tumor promoter, TPA, with special reference to lowering of cytotoxicity of T cells.

The mechanism of the previously observed enhancement of Epstein-Barr virus (EBV)-induced cell transformation of human lymphocytes by 12-0-tetradecanoyl-phorbol-13-acetate (TPA) was studied. A concentration of TPA (0.5 ng/ml) was used. In cultures of human cord blood lymphocytes infected with EBV in the presence of TPA, a larger number of EBV-associated nuclear antigen (EBNA)-positive and/or DNA synthesizing cells was observed than in the absence of TPA. In the virus-infected lymphocyte cultures of EBV-seropositive adult donors, in vitro regression of transformation, which is known to be caused by T lymphocytes, was suppressed by TPA, EBV-specific and -non-specific cytotoxicity of T cells generated in mixed cultures of peripheral blood lymphocytes (PBL) of seropositive adults and autologous lymphoblastoid cell line (LCL) cells was markedly lowered by the presence of TPA in the cultures, However, TPA had little effect on proliferation of T cells in stimulated cultures, and addition of TPA to the reaction mixture for the cytotoxicity test did not lower the cytotoxicity. These results suggest that TPA has an inhibitory effect on T cells which suppress EBV-transformation. THe effect on T cells, together with the direct promoting effect on proliferation of EBV-transformed cells, may explain the outcome of enhancement of EBV-induced LCL establishment from PBL of seropositive donors by TPA previously observed.

Adult↗
PubMed1981

Enhancement of outgrowth of EB virus-transformed cells from normal human peripheral blood by a tumor promoter, TPA.

Effect of 12-0-tetradecanoyl-phorbol-13-acetate (TPA) on the establishment of lymphoblastoid cell lines (LCL) following spontaneous tranformation of B cells by Epstein-Barr virus (EBV) from peripheral lymphocytes of healthy EBV-seropositive adults was examined. In the lymphocyte culture with TPA (0.5 ng/ml), the frequency of establishment of LCL increased and the time required for appearance of transformation decreased. A larger number of EBV-positive cells in the peripheral blood were detected in the assay by co-cultures with cord blood lymphocytes in the presence of TPA than in the absence of it. The enhancement of LCL establishment by TPA was largely abolished in the culture with EBV neutralizing antibody-containing human umbilical cord serum. This suggests that the enhancement by TPA may be caused mostly by transformation of coresident B lymphocytes infected with active virus induced from the EBV genome-positive cells by TPA.

Adult↗
PubMed1981

Strongyloides stercoralis hyperinfection: sequential changes of gastrointestinal radiology after treatment with thiabendazole.

Sequential changes of gastrointestinal radiology are described in a case of Strongyloides stercoralis hyperinfection. Duodenal dilatation, reflux of barium into the biliary and pancreatic duct, and mucosal thickening of the small intestine were the striking features before treatment. Although treatment with thiabendazole led to rapid and complete clearance of rhabditiform larvae, some abnormal radiologic changes in the small intestine persisted for approximately 4 months before the mucosal pattern reverted to normal.

Female↗
PubMed1981

Three phases in transformation of human lymphocytes by Epstein-Barr virus, as revealed by colony formation in soft agar.

Human cord lymphocytes were examined for colony formation in soft agar medium at various times after infection with Epstein-Barr virus (EBV). The transformation process could be divided into the following three sequential phases: (1) A pre-early phase, lasting about 10 hr post infection (pi), during which the number of transformed colonies was virus dose dependent. (2) An early phase, between about 10 and 60 hr pi, during which cloning efficiency was markedly lower than that of the pre-early phase. (3) A later phase, starting at about 60 hr pi, during which cloning efficiency was restored and the number of colony formers increased in an exponential fashion. EBV-associated nuclear antigen-positive cells first appeared at the beginning (12 hr pi) of the early phase and increased continuously thereafter. Increased DNA synthesis began at about 48 hr pi. These results suggest that the cloning efficiency of the infected cells changes during the transformation process, possibly reflecting altered cell sensitivity to agar.

Antigens, Viral↗
PubMed1981

Pathophysiologic analysis of peripheral blood lymphocytes from patients with primary immunodeficiency. I. Ig synthesis by peripheral blood lymphocytes stimulated with either pokeweed mitogen or Epstein-Barr virus in vitro.

In the present study 5 patients with common variable hypogammaglobulinemia (CVH) and 4 patients with selective IgA deficiency (IgA-D) were analyzed for the cellular defects responsible for impaired Ig synthesis with use of peripheral blood lymphocytes stimulated with either PWM or EBV in vitro. By the use of co-culture with PWM, all the patients examined had intrinsic B cell defects restricted to the synthesis of Ig class corresponding to the low or absent Ig class(es) in the sera. Two types of excessive suppressor T activity were found, which were abrogated by irradiation. One was isotype-nonspecific and the other was IgA-specific. Moreover, failure of IgA-specific helper T activity was demonstrated. The use of EBV as an agent that polyclonally activates B cells independently of T cells and monocytes should allow a clearer delineation of the level of the B cell defects. When co-cultured with EBV, B cells from 3 patients with CVH produced normal to subnormal quantities of IgM although they could produce no IgM upon co-culturing with normal T cells and PWM. B cells from 2 patients with CVH could produce IgM normally by stimulation with either PWM or EBV; however, there was no restoration to produce IgG or IgA in these patients. In addition, B cells from 2 patients with IgA-D produced not only IgG and IgM but also IgA almost normally at 4 days after in vitro stimulation with EBV.

Adolescent↗
PubMed1980

Ornithine transcarbamylase (OTC) in white blood cells.

A radiochemical assay method of ornithine transcarbamylase (OTC) was developed using labeled carbamyl phosphate as a substrate. The enzyme activities determined by this method in peripheral white blood cells from ten normal subjects were 1.32 +/- 0.95 nmoles/mg/hr and the apparent Km's, when assayed at pH 8.5, were 6.4 mM for ornithine and 0.6 mM for carbamyl phosphate. On the contrary, the apparent Km's of human liver OTC were 0.6 mM for ornithine and 0.12 mM for carbamyl phosphate. The average OTC activity of granulocytes was 1.0 nmoles/mg/hr, whereas that of mononuclear cells was 0.4 mmoles/mg/hr. Lymphoid cell lines were established from three normal subjects and an OTC-deficient infant. All these cell lines demonstrated no OTC activity. When arginine was removed from the medium and replaced by ornithine, the lymphoid cells were unable to grow in culture. On autoradiography, the lymphoid cells showed labelling at incubation in the presence of 14C-citrulline, but not with 14C-ornithine.

Amino Acid Metabolism, Inborn Errors↗
PubMed1980

Effect of cecum and appendix on 7 alpha-dehydroxylation and 7 beta-epimerization of chenodeoxycholic acid in the rabbit.

The effect of surgical removal of cecum and appendix on bile acid metabolism was studied in the rabbit. Bile acid composition of bile and intestinal contents were analyzed by gas-liquid chromatography and individual bile acids were further identified by mass spectrometry. In normal, intact rabbits (group I), the biliary bile acids consisted largely of deoxycholic acid (DA) 95.3 +/- 1.0 (mean +/- SE) %; cholic acid (CA) 2.3 +/- 1.1% and lithocholic acid (LA) 1.0 +/- 0.3% were also detected. Removal of cecum and appendix (group II) produced significant changes in biliary bile acid composition: DA fell to 58.3 +/- 31.8%, CA rose to 37.7 +/- 10.4%, and LA was barely detectable (0.3 +/- 0.1%). Administration of chenodeoxycholic acid (CDA), 125 mg/day, produced severe hepatotoxicity, reduced food intake, and produced weight loss (group III). Biliary LA rose to 15.0 +/- 1.3%, while DA was 61.3 +/- 14.0% and CDA 21.8 +/- 14.6% of total biliary bile acids. Feeding CDA to animals without cecum and appendix (group IV) resulted in a slight increase of LA (3.2 +/- 2.2%) compared to group III, and appreciable amounts of ursodeoxycholic acid (UDA) 32.0 +/- 9.8% and of 7-ketolithocholic acid (7-KLA) 3.0 +/- 0.6% appeared in bile. The animals of group IV exhibited no hepatotoxicity and ate and gained weight normally. These results indicate that the microbial population of cecum and appendix is active in 7alpha-dehydroxylation of primary bile acids and that removal of these organs results in an increased formation of UDA by an unknown mechanism.-Yahiro, K., T. Setoguchi, and T. Katsuki. Effect of cecum and appendix on 7alpha-dehydroxylation and 7beta-epimerization of chenodeoxycholic acid in the rabbit.

Animals↗
PubMed1979

Simultaneous presence of EBNA-positive and colony-forming cells in peripheral blood of patients with infectious mononucleosis.

EBNA-positive lymphoblast cells were detected in 0.1 to 0.9% of the T-cell-depleted lymphocytes obtained from peripheral blood samples of five patients with infectious mononucleosis (IM). The same blood specimens from four of the five patients contained cells that formed EBNA-positive colonies in soft agar containing EBV antibodies. The ratio of the colony formers to EBNA-positive cells was higher in blood samples taken early in the disease than in those obtained in later stages of the disease. The present results strongly suggest that EBV-transformed cells are present in the peripheral circulation of IM patients and that such cells can directly give rise to immortalized cell lines in vitro.

Adolescent↗
PubMed1979

Effect of coprophagy on bile acid metabolism in the rabbit.

The effect of coprophagy on the 7 alpha-dehydroxylation of biliary bile acids was studied in the rabbit. Bile acid composition of bile and intestinal contents was analyzed by gas-liquid chromatography and thin layer chromatography. Biliary bile acid composition of normal rabbits (n = 5) was: deoxycholic acid, 95.3 +/- 1.0SE % and cholic acid, 2.3 +/- 1.1SE %. When coprophagy was prevented, significant alterations were observed in biliary bile acid composition, including a considerable decrease in deoxycholic acid (82.5 +/- 2.8SE %, p less than 0.01) and a marked increase in cholic acid (15.2 +/- 3.0SE %, p less than 0.002). These results indicate that coprophagy is a factor causing an increase of the 7 alpha-dehydroxylated bile acid, deoxycholic acid (and lithocholic acid when the animals were fed chenodeoxycholic acid) in rabbit bile.

Animals↗
PubMed1979

A giant gallbladder.

A case of giant gallbladder is presented. A 36-yr-old female complaining of colicky pain and a mass in the right upper quadrant underwent cholecystectomy, when the giant gallbladder, 18 cm in length and 4 cm in maximum diameter, and an extremely long cystic duct was confirmed. Since neither marked biliary inflammation nor biliary obstruction was observed, this giant gallbladder is considered to be congenital.

Adult↗
PubMed1979

Conversion of 7-ketolithocholic acid to ursodeoxycholic acid by human intestinal anaerobic microorganisms: interchangeability of chenodeoxycholic acid and ursodeoxycholic acid.

Chenodeoxycholic acid, ursodeoxycholic acid and 7-ketolithocholic acid were incubated with human intestinal bacteria (source: 4 healthy males) at 37 degrees C for 72 hours in an anerobic condition. The bile acids of the products in culture medium were identified by three independent methods, thin layer chromatography, gas-liquid chromatography and GLC-mass spectrometry. Lithocholic acid, ursodeoxycholic acid and 7-ketolithocholic acid were observed in the culture of chenodeoxycholic acid. Lithocholic acid, chenodeoxycholic acid and 7-ketolithocholic acid were observed in the culture of ursodeoxycholic acid. Chenodeoxycholic acid and ursodeoxycholic acid were produced from 7-ketolithocholic acid. These data may suggest that chenodeoxycholic acid and ursodeoxycholic acid are interconvertible via 7-ketolithocholic acid by the mixed culture of human intestinal microorganisms under an anaerobic condition.

Anaerobiosis↗
PubMed1979

Congenital multiple cystic dilatation of the intrahepatic biliary ducts (two cases with simple type of Caroli's disease).

Two cases of Caroli's diseases (simple type) precisely diagnosed prior to the operation by the direct cholangiography, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography, were reported. They both had a long cystic duct, and association of cystic lesions of bilateral kidneys was revealed in one of them. Excessive biliary output had been observed postoperatively in both of them. A cholecystectomy and choledochodrainage successfully gave rise to favourable results in both cases reported.

Adult↗
PubMed1979

Chromosome aberrations in B lymphocytes of atomic bomb survivors.

Although chromosome aberrations in T lymphocytes and bone marrow cells have been reported in atomic bomb survivors, the presence of chromosome abnormalities has not been demonstrated in B lymphocytes because of the technical difficulties involved in B-lymphocyte separation. A method for detecting chromosome aberrations in B lymphocytes was established by "stimulation" of B lymphocytes with Epstein-Barr virus (EBV) instead of "separation" of B lymphocytes by rosette formation. The EBV-stimulated lymphocytes were isolated as single colonies in soft agar and transferred to liquid culture for further cell growth. The EBV-stimulated B lymphocytes of two heavily exposed survivors showed 50% and 12.5% chromosome abnormalities 30 yr after exposure to the effects of the atomic bomb. The former patient seemed to have a karyotypically abnormal clone of B lymphocytes in vivo. The method used in this study and the evidence of chromosome aberrations in B lymphocytes for long periods after radiation exposure will be useful and important in elucidating the malignant processes of acute lymphocytic leukemia, B-cell lymphoma, and multiple myeloma among high-risk groups having a history of accidental or therapeutic exposure to radiation or radiomimetic drugs.

Adolescent↗