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Biomedical subjects

K Katagiri

Publications and source records attributed to K Katagiri.

At least 55 records · Page 3Linked to original sources

Enhancing effects of vasoconstrictors on bile flow and bile acid excretion in the isolated perfused rat liver.

The effects of vasoconstrictors on bile flow and bile acid excretion were examined in single-pass isolated perfused rat livers. Administration of norepinephrine (NE), 4 nmol/min, plus continuous infusion of taurocholate (TC) (1.0 mumol/min) rapidly increased bile flow in 1 min, and from min 5 until the end of NE administration (late period) bile flow remained above the basal level (111.7 +/- 2.2%), as did bile acid output (114.6 +/- 1.8%). Without TC infusion, administration of NE produced no increase in the late period. Administration of NE plus taurochenodeoxycholate (1.0 mumol/min) increased bile flow and bile acid output in the late period to 121.9 +/- 7.0 and 137.1 +/- 6.8%, respectively. With NE plus taurodehydrocholate, the respective values were only 105.4 +/- 1.6 and 104.1 +/- 4.0%. When horseradish peroxidase (HRP) (25 mg) was infused over 1 min with continuous NE, the late peak (20-25 min) of HRP elimination into bile significantly exceeded that of untreated controls (P < 0.01). These observations suggest that vasoconstrictors enhance biliary excretion of more hydrophobic bile acids, in part by stimulating vesicular transport.

Animals↗

Differential regulation of leukocyte function-associated antigen-1/ intercellular adhesion molecules-1-dependent adhesion and aggregation in HL-60 cells.

Activation of integrin and organization of cytoskeletal proteins are highly regulated in cell adhesion and aggregation. The interaction of leukocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecules-1 (ICAM-1) mediates cell adhesion and aggregation, which facilitate leukocyte trafficking to inflamed tissues and augment effector functions. We investigated how LFA-1/ICAM-1-mediated adhesion and aggregation are regulated in HL-60 cells induced to differentiate into neutrophils by retinoic acid (RA). Uninduced HL-60 cells did not bind to ICAM-1 even with stimulation by 12-0-tetradecanoyl phorbol-13-acetate, although they express LFA-1 on the cell surface. When cultured with RA for 24 hours, HL-60 cells were able to adhere to ICAM-1 constitutively. The induction of adhesion did not accompany any change in surface density of LFA-1, indicating that the avidity of LFA-1 was increased. The change in its avidity required de novo synthesis of proteins. Although ICAM-1 was intensely expressed on RA-induced HL-60 cells, these cells did not show any cellular aggregation. The HL-60 cells transfected with the active form of Ras (Val12) exhibited LFA-1/ICAM-1-dependent aggregation by RA stimulation without change in the avidity of LFA-1. In these Ras-transfectants, a cytoskeletal protein, paxillin, was tyrosine-phosphorylated, and the level of F-actin increased. Transforming growth factor (TGF) beta, as well as cytochalasin D, prevented both the tyrosine phosphorylation of paxillin and the aggregation without any effects on the avidity of LFA-1. Thus, an increase in the avidity of LFA-1 was not sufficient for the induction of aggregation, which required activation of Ras and reorganization of cytoskeletal proteins. These results suggest that distinct regulatory mechanisms control LFA-1/ICAM-1-dependent adhesion and aggregation in HL-60 cells differentiating into neutrophils.

Actins↗

Lyn and Fgr protein-tyrosine kinases prevent apoptosis during retinoic acid-induced granulocytic differentiation of HL-60 cells.

The human promyelocytic leukemia cell line HL-60 can be induced to differentiate toward neutrophils and subsequently die via apoptosis in vitro. In this paper, we investigated the roles of protein-tyrosine kinases (PTKs) in retinoic acid (RA)-induced granulocytic differentiation of HL-60 cells. Accompanying the RA-induced differentiation, activities of src family PTKs Lyn and Fgr became detected and reached a plateau 2 days after the stimulation. The immunoblotting using anti-phosphotyrosine antibody (PY-20) showed that the proteins of 56 and 53 kDa were predominantly tyrosine-phosphorylated at day 2. Adsorption and immunoprecipitation of the cell lysate by specific antibodies evidenced that these phosphotyrosine-containing proteins are Lyn and Fgr PTKs. The degree of both activities and tyrosine phosphorylation of these PTKs was reduced to be minimal at day 5 when the HL-60 cells start to die by apoptosis. The inhibitors of PTKs, herbimycin A and genistein, were demonstrated to cause premature cell death of HL-60 cells in the presence of RA. The death was the consequence of an apoptotic process. The Ra-treated HL-60 cells, when incubated with specific c-lyn or c-fgr antisense oligodeoxynucleotide, also underwent premature death at day 2. These data implicate that Lyn and Fgr PTKs prevent programmed cell death to promote granulocytic differentiation of HL-60 cells.

Apoptosis↗

Effects of degeneration on the elastic modulus distribution in the lumbar intervertebral disc.

STUDY DESIGN: Local elastic moduli of sliced intervertebral disc specimens were studied after establishing the relation between the elastic modulus and indentation behaviors by model tests using polyurethane specimens. OBJECTIVES: This study presents a method to quantify the distribution of compressive elastic moduli in the lumbar intervertebral disc and to clarify the effects of degeneration on the distribution. SUMMARY OF BACKGROUND DATA: No study has been performed to evaluate the distribution of axial compressive elastic moduli, which is supposed to relate previous biomechanical, biological, and biochemical findings regarding the intervertebral disc. METHODS: Local compressive elastic moduli of the intervertebral disc were estimated by indentation tests. To evaluate the distribution of elastic moduli, indentation tests were performed at nodal points of a 10 mm x 10 mm network on a specimen. Nine cadaveric lumbar discs (L3-L4 and L4-L5) with various degrees of degeneration were tested. The age of subjects ranged 39 to 90 years (mean, 58.4 years). RESULTS: The distribution of elastic moduli in normal discs was symmetric about the midsagittal plane. The mean elastic modulus in the nucleus pulposus was 5.8 kPa and those of the anterior and posterior anulus fibrosus were 110.7 and 75.8 kPa, respectively. The elastic moduli in the lateral portions were the lowest in the normal anulus, and were close to the values of the nucleus. Compared to normal discs, degenerated discs showed irregular distributions of elastic moduli. The elastic moduli of the degenerated nucleus were higher than those in normal discs. CONCLUSIONS: The distribution of elastic moduli is much different between discs with and without degeneration.

Adult↗

Purification and structural analysis of extracellular matrix of a skin tumor from a patient with juvenile hyaline fibromatosis.

Juvenile hyaline fibromatosis is a rare mesenchymal dysplasia that is inherited in an autosomal recessive fashion. The histological features of the tumor-like lesions are characterized by the deposition of amorphous hyaline material in the extracellular spaces of the dermis and soft tissues. We have analyzed the hyaline substance in a specimen of a skin tumor obtained from a 4-year-old Japanese girl with juvenile hyaline fibromatosis. It was found to consist mainly of type VI collagen; a small amount of type I collagen was also present. These components were separated by DEAE-cellulose ion-exchange chromatography under reducing conditions. The ratio of the dry weights of type I and type VI collagen was 1:4. Of the three chains of type VI collagen (alpha 1(VI), alpha 2(VI) and alpha 3(VI)), alpha 3(VI) was the most abundant. Glycosaminoglycans in the tumor tissue comprised dermatan sulfate, chondroitin sulfate and hyaluronan, with dermatan sulfate predominating. In contrast, hyaluronan is the most abundant in normal skin.

Amino Acid Sequence↗

A case of Ki-1 positive anaplastic large cell lymphoma transformed from mycosis fungoides.

A case of cutaneous Ki-1 positive anaplastic large cell lymphoma which developed in the plaque stage of mycosis fungoides was described. A 73-year-old woman who had suffered from pruritic scaly eruptions over her entire body for more than two decades was admitted because of an ulcerated tumor measuring 45 x 55 x 15 mm and several satellite tumors on the buttock. All tumorous lesions were resected without recurrence to date. Histochemical study revealed that the tumor consisted of large anaplastic cells which were Ki-1 (CD30)-positive and LCA-negative. Some of the erythematous plaques contained LCA-positive, small-sized atypical lymphocytes. In other plaques which developed two years later, there were large Ki-1-positive atypical cells. In the specimens obtained from the tumor and the plaque, the same pattern of T-cell receptor gene rearrangements was detected. These findings indicate that both Ki-1 positive anaplastic cells in the tumor and atypical lymphoid cells in the plaques were derived from the same T cell clone.

Aged↗

Drug induced acute generalized exanthematous pustulosis.

A 62-year-old woman with diabetic triopathy developed widespread erythematous macules, numerous pustules, and a high fever after she underwent electric coagulation for vitreous hemorrhage. She was administered several drugs at that time. After discontinuation of the drugs, the eruption disappeared, and the fever returned to normal within two weeks. A positive patch test with isepamicin sulfate highly suggested that the symptoms described above were due to drug allergy. Cadralazine, which was positive in the drug lymphocyte stimulation test (DLST), could not be excluded from the causative drugs. A false-positive DLST with ofloxacin was confirmed by an accidental challenge test. To our knowledge, this is the first report of acute generalized exanthematous pustulosis due to isepamicin sulfate and/or cadralazine.

Acute Disease↗

Bacteroides fragilis pyomyositis in a patient with multiple myeloma.

Pyomyositis is a bacterial infection with abscess formation affecting large skeletal muscles. It is predominantly caused by Staphylococcus aureus. The disease is common in tropical areas, but rare in temperate climates. We report a patient with multiple myeloma who developed a giant elastic tumor on the right thigh and a hen egg-sized tumor on the right upper arm. MR imaging revealed cystic spaces in the femoral quadriceps and brachial biceps muscles. A large amount of pus with foul smell was removed by incision, drainage and aspiration of the two tumors. The lesions were successfully treated with intravenous administration of antibiotics. Repeated bacterial cultures yielded only Bacteroids fragilis. To our knowledge, this is the first report of pyomyositis due to Bacteroides fragilis.

Aged↗

A case of stasis papillomatosis associated with psoriasis vulgaris.

A markedly obese, 41-year-old Japanese man who had suffered from psoriasis vulgaris for several years visited us with elephantiasis-like swelling of his lower legs of three months' duration. His right lower leg showed marked papillomatosis with thick scales, and the left lower leg was eroded and papillomatous. Although direct lymphography of his lower extremities showed no abnormality, indirect lymphography revealed local lymphatic damage in the involved skin. Histological examination showed hyperkeratosis, marked papillomatosis, proliferation of capillaries in the upper dermis, and lymphectasia in the lower dermis. The lesions were much improved by washing and topical use of corticosteroids for two months. It was suspected that obesity and the preceding psoriatic lesions caused local lymphatic disturbances, followed by the development of stasis papillomatosis.

Adult↗

Monoclonal antibodies (NU-T1 and NU-T2) recognizing antigens expressed on human T cells.

Two murine monoclonal antibodies (mAb) designated as NU-T1 and NU-T2 were generated to identify the novel antigens expressed on human T cells. NU-T1 reacted with peripheral blood T cells, but not with granulocytes or monocytes, whereas NU-T2 were not reactive with peripheral blood lymphocytes, granulocytes or monocytes. Both NU-T1 and NU-T2 reacted with thymocytes. The incidence of NU-T1 or NU-T2 reactivity with the leukemic cells from patients with various types of leukemia was as follows: 12/12 or 4/12 in acute lymphocytic leukemia (ALL) of T cell type, 6/6 or 0/7 in adult T cell leukemia, 0/6 or 0/19 in ALL of non-T non-B cell type, and 0/8 or 0/8 in acute myelocytic leukemia, respectively. The incidence of NU-T1 and NU-T2 reactivity with human leukemic T cell lines were 4/10 and 5/10, respectively. In contrast, neither NU-T1 nor NU-T2 reacted with B cell lines, non-T non-B cell lines, or myeloid cell lines tested. These results indicate that NU-T1 and NU-T2 recognize two distinct differentiation antigens expressed on the cells in the T cell lineage. These mAb would be useful reagents to study the function of human T cells and the immunophenotyping of human T cell malignancies.

Antibodies, Monoclonal↗

Comparative studies on bile flow and biliary lipid excretion after bile-acid loading in normal and partially hepatectomized rats.

This study was performed to investigate sequential changes in bile secretion and biliary lipids after taurocholic acid (TCA) loading of regenerating rat liver. TCA was administered intravenously at stepwise-increasing doses to groups of non-operated control and partially hepatectomized rats, 24, 72 and 168 h after surgery. Bile flow, bile-acid output (BAO) and phospholipid output (PLO) (expressed per gram of liver) in partially hepatectomized rats increased more than in the controls. Using an isolated perfusion rat-liver system, TCA infusion was also carried out on groups of non-operated control and hepatectomized rats 72 h after operation. Again bile flow, BAO and PLO (expressed per gram of liver) were significantly higher in the partial hepatectomy case, mirroring the results obtained in vivo. When horseradish peroxidase (HRP) was pulse-loaded in isolated perfusion preparations, the second peak of biliary HRP secretion in hepatectomized rats was significantly higher than in controls. We conclude that increased bile-acid flow in partially hepatectomized rats is dependent upon acceleration of vesicular transport accompanying or following proliferation in regenerating livers.

Animals↗

Immunopathological mechanisms of human T cell lymphotropic virus type 1 (HTLV-I) uveitis. Detection of HTLV-I-infected T cells in the eye and their constitutive cytokine production.

The immunopathology of human T cell lymphotropic virus type 1 (HTLV-I) uveitis was addressed by using T cell clones (TCC) established from the intraocular fluid of patients with HTLV-I uveitis. Proviral DNA of HTLV-I was identified in 55 out of 94 (59%) or 13 out of 36 (36%) TCC from the ocular fluid or the peripheral blood of these patients, respectively. Most of HTLV-I-infected TCC had a CD3+ CD4+ CD8- phenotype. HTLV-I infection on TCC was confirmed by analysis of the viral mRNA, nucleotide sequence, virus-associated proteins, and virus particles. HTLV-I-infected TCC, but not HTLV-I negative TCC, constitutively produced high amounts of IL-6 (1,336 +/- 1,050 pg/ml) and TNF-alpha (289 +/- 237 pg/ml) in the absence of any stimuli. HTLV-I-infected TCC from the ocular lesion also constitutively produced high amounts of IL-1 alpha (12,699 pg/ml), IL-2 (61 pg/ml), IL-3 (428 pg/ml), IL-8 (1,268 pg/ml), IL-10 (28 pg/ml), IFN-gamma (5,095 pg/ml), and GM-CSF (2,886 pg/ml). Hydrocortisone, a drug effective in vivo for the treatment of HTLV-I uveitis, severely depressed cytokine production in vitro in most cases. In summary, the results demonstrated direct evidence of HTLV-I infection of the eye and suggest that cytokines produced by HTLV-I-infected T cells are responsible for the intraocular inflammation in patients with HTLV-I uveitis.

Adult↗

Activation of Ras and formation of GAP complex during TPA-induced monocytic differentiation of HL-60 cells.

In this study, it was shown that the proportion of guanosine triphosphate (GTP)-bound active Ras increased in TPA (12-o-tetradecanoyl phorbol-13-acetate)-induced monocytic differentiation of HL-60 cells. The increase of active Ras was observed at 24 hours after TPA stimulation and attained to threefold (15%) over the proportion in nontreated HL-60 cells. Herbimycin A, an inhibitor of tyrosine kinase, prevented the activation of Ras, as well as the induction of monocytic differentiation. In parallel with the activation of Ras, the proteins with molecular weights of 52, 56, 62, and 190 kD were tyrosine-phosphorylated and formed a complex with GTPase-activating protein (GAP) for Ras. In addition to the 116-kD GAP (type I GAP), the 100-kD GAP (type II GAP) molecule was markedly induced at 24 hours after TPA stimulation of HL-60 cells. These phenomena sustained for a further 24 hours during monocytic differentiation. However, they were not observed during retinoic acid-induced granulocytic differentiation of the cells. The HL-60 transfectants, which expressed a dominant inhibitory Ha-ras Asn17, showed a low level of tyrosine-phosphorylated GAP-associated proteins and did not undergo full differentiation in response to TPA. Taken together, these data indicate that the activation of Ras and GAP complex formation mutually correlate and function downstream of protein-tyrosine kinases in the signaling pathway for monocytic differentiation of HL-60 cells.

Benzoquinones↗

Connective tissue naevus with pseudo-Hurler polydystrophy.

We report a 39-year-old patient with a huge connective tissue naevus on his back, in association with pseudo-Hurler polydystrophy (mucolipidosis III). As far as we are aware, this is the first report of the coexistence of these two rare conditions. The lesional skin was composed of densely packed, coarse collagen fibres, which were immunohistochemically found to consist of type I, type III and type VI collagens. The amount of elastic fibres was moderately reduced. The glycosaminoglycan content of lesional skin was similar to that in a normal control. Activities of several glycosidases were markedly decreased in cultured fibroblasts.

Adult↗

Endothelin-1 stimulates bile acid secretion and vesicular transport in the isolated perfused rat liver.

The effects of endothelin (ET) on portal pressure and bile secretion were examined using isolated perfused rat liver and rat hepatocyte preparations. ET-1 raised portal pressure dose dependently; administration at a high dose (10(-9) mol) induced a > 200% increase along with reduced bile flow and decreased secretion of bile acid and phospholipids. However, a low dose (10(-10) mol) of ET-1 brought about a < 100% portal pressure rise, enhanced both bile flow and excretion of bile acid and phospholipids, and significantly increased transfer of preadministered horseradish peroxidase (HRP) into bile. In addition, values for Ca2+ concentrations, examined by indo 1 fluorescence, were elevated in isolated hepatocytes after administration of ET-1. Papaverine suppressed the low-dose ET-1 stimulation effects on both portal pressure and bile secretion. Moreover, it also reduced the HRP excretion and suppressed intracellular Ca2+ release. This study demonstrated that ET-1 stimulates vesicular transport, probably via promotion of intracellular Ca2+ release, and, as a result, increases bile acid-dependent bile flow.

Animals↗