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H Kobashi

Publications and source records attributed to H Kobashi.

At least 19 recordsLinked to original sources
PubMed2006

Persistent elevation of serum alanine aminotransferase levels leads to poor survival and hepatocellular carcinoma development in type 1 autoimmune hepatitis.

BACKGROUND: Although the prognosis of type 1 autoimmune hepatitis is generally good with immunosuppressive treatment, the disease progresses in some patients despite the treatment. The prognosis may be determined by the clinical course. AIM: To evaluate the long-term prognosis and assess the predictive factors for a serious event, including the development of hepatocellular carcinoma or death. METHODS: Sixty-nine patients with type 1 autoimmune hepatitis were prospectively followed up regularly, with a median follow-up period of 96 months (49-201 months). RESULTS: During the follow-up period, three patients (4%) developed hepatocellular carcinoma, and two of these three patients died. Another patient died of liver failure. The 10-year survival rate was 98%, and the 10-year hepatocellular carcinoma-free rate was 93%. The four patients experiencing a serious event received higher maintenance doses of corticosteroid during their follow-up periods than those did not. However, serum alanine aminotransferase levels during the follow-up period were higher in these four patients than in the others. CONCLUSIONS: Persistent elevation of serum alanine amniotransferase levels during the follow-up period, rather than factors existing prior to medical treatment is considered to be an important prognostic factor, and it is indicated that poor outcomes may result from the resistance to immunosuppressive treatment.

Adolescent↗
PubMed1997

Accumulation of multiple T-cell clonotypes in the liver of primary biliary cirrhosis.

The histological hallmark of primary biliary cirrhosis (PBC) is the destruction of the interlobular and septal bile ducts accompanied by a dense accumulation of lymphocytes; this constellation of features is termed chronic nonsuppurative destructive cholangitis. To analyze the T cells responsible for bile duct destruction, the T-cell receptor (TCR) Vbeta repertoire was studied in liver biopsy specimens, and also in peripheral blood lymphocytes (PBL) obtained from seven patients with PBC in the early stage (Scheuer's stage I or II). The complementary DNA (cDNA) of each TCR Vbeta1-20 chain was amplified by reverse-transcription polymerase chain reaction (RT-PCR), and the PCR products were examined by single-strand conformation polymorphism (SSCP) analysis. On the RT-PCR/SSCP analysis, a leukemic cell line, HPB-ALL, showed bands in TCR Vbeta 5.2 and Vbeta 6, indicating clonal expansion with distinct TCR. In the PBL from healthy subjects, the PCR products were amplified from many TCR Vbeta and were shown as smears on SSCP, suggesting that PBL consist of diverse T-cell clones. In PBC, many TCR Vbeta products were amplified by RT-PCR in both liver tissues and PBL, and no biased expression of a particular Vbeta was observed. SSCP analysis revealed multiple bands in most Vbeta chains, suggesting the presence of selected but multiple T-cell clones. Both the number and types of Vbeta showing clonal expansion were heterogeneous in the PBC patients. A comparative RT-PCR SSCP analysis of each TCR Vbeta between tissue lymphocytes and PBL revealed the presence of some identical T-cell clones in both the PBC liver and the PBL. These results suggest that T cells infiltrating the liver in PBC consist of multiple clonotypes and that T-cell clones accumulated in the liver are also present in PBL.

Adult↗
PubMed1995

Activated liver macrophages in human liver diseases.

Immunohistochemical analysis using monoclonal antibodies specific for cells of monocyte/macrophage lineage reveals that resident liver macrophages have a phenotype distinct from that of monocytes or activated liver macrophages. Liver macrophages consist of heterogeneous cell populations in maturation (matured 25F9-positive and immature 25F9-negative) but the ratio of two populations is constant in normal and diseased livers. The expression of CD14 is down-regulated in resident liver macrophages as compared to that in monocytes, while the expression of 25F9 is up-regulated. On the other hand, the expressions of CD14 and Fc gamma RI are up-regulated in activated liver macrophages in viral and autoimmune hepatitis. In vitro culture of monocytes in medium without cytokines induces the phenotype similar to that of resident liver macrophages. Addition of macrophage-colony stimulating factor or interferon-gamma into the culture medium induces the expression of Fc gamma RI, the phenotype of which resembles that of activated liver macrophages. These results suggest that liver macrophages consist of heterogeneous cell populations and that both phenotype and function are affected by the local milieu of cytokines.

Animals↗
PubMed1994

Receptor-mediated endocytosis of chemically modified albumins by sinusoidal endothelial cells and Kupffer cells in rat and human liver.

Human serum albumin (HSA), formaldehyde-treated HSA (FHSA), and HSA polymerized with glutaraldehyde (pHSA) were conjugated with colloidal gold (15 (15G) or 50 (50G) nm in diameter). The labeled proteins were injected into the portal veins of rats and followed by electron microscopy. Both 15G-FHSA and 15G-pHSA were taken up by sinusoidal endothelial cells (Ec) and Kupffer cells (Kc). Five minutes after injection, gold particles were observed on the surface of Ec and Kc. At 10 min, most gold particles were gathered in the coated pits and vesicles of Ec. In Kc, gold particles were observed in both coated vesicles and macropinocytotic vesicles. At 15 min, the gold particles were localized mainly in the endosomes and some lysosomes of Ec and in the large vacuoles of Kc. At 30 min, the gold particles had been gathered into the secondary lysosomes and condensed. At 60 min, some gold particles were observed in the cytoplasm of Ec. The fate of 15G-pHSA was the same as that of 15G-FHSA. Simultaneous injection of 15G-pHSA and 50G-FHSA revealed that particles of both sizes were taken up together into the coated pits and vesicles of Ec. Preperfusion of livers with unlabeled FHSA, pHSA, or formaldehyde-treated bovine serum albumin (FBSA) inhibited the uptake of 15G-FHSA or 15G-pHSA by Ec. In a human liver biopsy specimen, both 15G-FHSA and 15G-pHSA were taken up by Ec and Kc through coated vesicles, as in the rat liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Immunohistochemical phenotyping of liver macrophages in normal and diseased human liver.

The phenotypical heterogeneity of human liver macrophages was analyzed with monoclonal antibodies that recognize antigens specific for the monocyte-macrophage lineage. Most liver macrophages in normal and diseased liver were positive for CD68, whereas fewer matured macrophages were detected by 25-F9. Comparative staining of mirror sections revealed some to be doubly positive and others to be singly CD68 positive. Quantitative analysis confirmed the difference, suggesting heterogeneity of maturation in liver macrophages. Most liver macrophages in the normal liver were negative for CD14, a receptor for lipopolysaccharide and lipopolysaccharide-binding protein complexes. Liver macrophages in liver diseases were activated to express CD14 at varying degrees and were involved in the clearance of lipopolysaccharide-lipopolysaccharide-binding protein complexes. Fc gamma RI, a receptor for monomeric IgG that is involved in antibody-mediated cell cytotoxicity, was negative in the normal liver, but was expressed in liver macrophages at inflammatory sites (e.g., in piecemeal and focal necrosis) in diseased livers. Fc gamma RII was expressed in most liver macrophages, as well as in sinusoidal endothelial cells; Fc gamma RIII was expressed in a smaller number of liver macrophages. Expression of Fc gamma RII and Fc gamma RIII was increased in chronic active hepatitis. These results suggest that liver macrophages are heterogeneous in maturation and function and that they are activated in liver diseases as shown by the novel expression of CD14 and Fc gamma RI. The restricted expression of Fc gamma RI indicates that Fc gamma RI-positive macrophages, in cooperation with cytotoxic T lymphocytes, may play an important role in liver cell injury through antibody-mediated cell cytotoxicity.

Antigens, CD↗
PubMed1994

Nonsuppurative cholangitis is induced in neonatally thymectomized mice: a possible animal model for primary biliary cirrhosis.

Neonatally thymectomized mice are unique in that they are prone to organ-specific autoimmune diseases. We investigated whether autoimmune cholangitis could be induced in these mice when they were immunized with biliary antigens. Neonatally thymectomized A/J mice were immunized with porcine intrahepatic bile duct epithelial cells (group 1), porcine gallbladder epithelial cells (group 2), porcine splenocytes (group 3) or Freund's adjuvant (group 4). Nonthymectomized mice were immunized with bile duct epithelial cells (group 5) or Freund's adjuvant (group 6). The cell suspensions were injected intraperitoneally with Freund's adjuvant once a week for 8 wk. In group 1 varying amounts of mononuclear cells infiltrated around the bile duct in 14 of 22 mice, whereas little or no accumulation was noted in other groups. Ultrastructural observations revealed that the inflammatory cells consisted of lymphocytes, plasma cells and macrophages. The bile duct showed degenerative changes and some lymphocytes infiltrated between bile duct epithelial cells. An immunohistochemical study showed that the accumulated lymphocytes consisted of CD4+ and CD8+ T cells, as well as B cells. Both major histocompatibility complex class I and class II antigens were expressed on bile duct epithelial cells. Antimitochondrial antibody was demonstrated in some mice in groups 1 (9 of 17), 2 (2 of 3) and 5 (4 of 5) by immunofluorescence; the antibody reacted with the 68, 52 and 47 kD polypeptides of the pyruvate dehydrogenase complex on Western blotting. These findings suggest that autoimmune cholangitis can be induced in neonatally thymectomized mice stimulated with biliary antigens and that these mice could be a suitable animal model for primary biliary cirrhosis.

Animals↗
PubMed1993

Hemostasis of gastric variceal hemorrhage by transileocoecal and transhepatic obliteration.

Obliteration for gastric or duodenal variceal hemorrhage was performed via transileocoecal or transhepatic portal catheterization in 8 patients with portal hypertension. The patients were 6 men and 2 women, whose average age was 59 years. All of the patients had cirrhosis of the liver. The obliteration was performed as an emergency procedure in 6 cases, and 2 patients were electively treated. Transileocoecal obliteration (TIO) and transhepatic obliteration (PTO) were selected for 6, and 2 patients, respectively. Variceal bleeding was successfully controlled in all patients after completion of the therapy. One patient died after 3 months when duodenal variceal bleeding recurred. Elective surgical operations were performed on 2 patients after the initial therapy, because the vein feeding toward the varices remained. Six of the patients have survived to date without bleeding. Transient oliguria and jaundice after the therapy were noticed in 2 patients. Histological examination revealed cast formation of polymerized cyanoacrylate in the obliterated gastric varices of 2 patients. TIO and PTO seem to be safe, effective procedures to stop bleeding from ectopic varices, gastric or duodenal. This therapy is useful either to obtain accurate information about the varices or to obliterate the collateral veins in patients with ruptured ectopic varices.

Adult↗
PubMed1992

Decrease of pyruvate dehydrogenase phosphatase activity in patients with congenital lactic acidemia.

We developed an assay method for pyruvate dehydrogenase phosphatase activity using [1-14C]pyruvate and measured pyruvate dehydrogenase phosphatase activity in cultured skin fibroblasts from three patients with congenital lactic acidemia due to a defect in activation of the pyruvate dehydrogenase complex. The enzyme activity of their fibroblasts was significantly reduced to 50.7%, 64.6% and 63.1% of that of control fibroblasts. These observations suggest that the defect in activation of the pyruvate dehydrogenase complex in these patients might be due to a reduction in pyruvate dehydrogenase phosphatase activity.

Acidosis, Lactic↗
PubMed1992

Quantitative analysis of activated Kupffer cells in viral hepatitis: application of computer image analysis for lectin histochemistry.

Lectin histochemistry revealed that Kupffer cells in the normal liver bound lectins such as Concanavalin A (Con A), Ricinus communis agglutinin (RCA) and Wheat germ agglutinin (WGA), but did not bind Peanut agglutinin (PNA), Dolichos fibflorus agglutinin (DBA), Ulex europaeus agglutinin I (UEA-I) or Soybean agglutinin (SBA). Kupffer cells in viral liver diseases, however, bound the PNA lectin and the binding was specific to Kupffer cells in liver parenchyma. Computer image analysis was performed using light micrographs of sections stained with immunoperoxidase and diaminobenzidine (DAB). The dark brown area of reaction products was detected by analyzing each color component (red, green and blue) in the picture and was expressed as the percent area in the parenchyma. Quantitative analysis revealed the percent area occupied by Kupffer cells positive for the PNA lectin was as follows: acute hepatitis, 2.83 +/- 0.74; chronic persistent hepatitis, 2.51 +/- 0.88; chronic aggressive hepatitis, activity moderate and severe, 4.71 +/- 2.23 and 3.45 +/- 1.84; and liver cirrhosis, 1.96 +/- 0.99. The percent area of Kupffer cells was significantly higher in CAH2A than that in chronic persistent hepatitis or in liver cirrhosis. These results suggest that the PNA lectin could be used as a marker for activated Kupffer cells and that activated Kupffer cells were increased in volume in chronic aggressive hepatitis.

Biopsy↗
PubMed1991

Screening for disorders of pyruvate metabolism by measuring the ratio of the rates of lactate production and pyruvate decarboxylation in cultured skin fibroblasts.

We assayed the rates of lactate production from [1-14C]pyruvate and decarboxylation of [1-14C]pyruvate in cultured skin fibroblasts from 8 patients with disorders of pyruvate metabolism and 16 control subjects. The disorders of pyruvate metabolism could be more readily detected by measuring the ratio between the rates of lactate production and pyruvate decarboxylation by cultured skin fibroblasts than by measuring either the rate in isolation.

Acidosis, Lactic↗
PubMed1991

Clinical and biochemical findings in parents of children with vitamin D-dependent rickets Type II.

Vitamin D-dependent rickets type II is a rare disease caused by a disorder of the receptor for 1, 25-dihydroxyvitamin D (1, 25(OH)2D). Several parameters of this receptor-effector system were investigated to obtain biochemical information on the presumed heterozygotes of vitamin D-dependent rickets type II in parents of five patients and in their age-matched controls. It was found that the serum concentrations of 1, 25-(OH)2D and 24,25-dihydroxy-vitamin D (24,25(OH)2D), and the ratio of 1,25-(OH)2D/24,25-(OH)2D differed significantly in the parents from those of the patients and the respective control groups. In the parents' cultured skin fibroblasts, the activity of 25-hydroxyvitamin D-24-hydroxylase induced by 10(-8) mol/L 1, 25-(OH)2D3 ranged from 50 to 82% of that of their controls (versus 1-13% of controls for the patients). The binding capacity of the parents' [3H]1, 25-(OH)2D3 to the nucleus was 38-54% of that of their control subjects (versus 7-27% of controls for the patients). The parents' values were thus in a range between those of the patients and the control groups. These findings suggest that, in the parents, a partial impairment of the receptor system for 1, 25-(OH)2D led to an imbalance of vitamin D metabolism, thus confirming that vitamin D-dependent rickets type II is an autosomal recessive inherited disease. Serum concentrations of 1, 25-(OH)2D and 24, 25-(OH)2D may provide useful parameters for detecting heterozygotes of this disease.

24,25-Dihydroxyvitamin D 3↗
PubMed1990

25-Hydroxyvitamin D-24-hydroxylase in phytohemagglutinin-stimulated lymphocytes: intermediate bioresponse to 1,25-dihydroxyvitamin D3 of cells from parents of patients with vitamin D-dependent rickets type II.

A method for assay of 25-hydroxyvitamin D-24-hydroxylase (24-hydroxylase) activity in phytohemagglutinin (PHA)-stimulated lymphocytes was applied to determine whether vitamin D-dependent rickets type II (VDDR II) is hereditary. In normal lymphocytes incubated with PHA for 3 days, maximal and half-maximal responses of 24-hydroxylase were observed after exposure to 10(-8) mol/L and (1.3 +/- 0.4) x 10(-9) mol/L 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], respectively. These responses were similar to those of cultured skin fibroblasts. In contrast, after exposure to 10(-8), 10(-7), and 10(-6) mol/L 1,25-(OH)2D3, no 24-hydroxylase activity was detected in cells from patients with VDDR II, and intermediate activity was observed in cells from their parents. These findings indicated the presence of an intracellular receptor-effector system for 1,25-(OH)2D3 in peripheral lymphocytes. Heterozygotes of VDDR II could be identified, and autosomal recessive inheritance of the disease was demonstrated. Detection of heterozygotes of this disease was not possible by assay of inhibition of thymidine incorporation, another marker of the function of 1,25-(OH)2D3 in PHA-stimulated lymphocytes. Therefore, assay of 24-hydroxylase induction reflected the receptor status more closely than assay of inhibition of DNA biosynthesis. The assay of 24-hydroxylase activity in PHA-stimulated lymphocytes described here will be useful for diagnosis of VDDR II and study of families of patients with this disease.

24,25-Dihydroxyvitamin D 3↗
PubMed1989

Effect of sodium dichloroacetate on human pyruvate metabolism.

Sodium dichloroacetate (DCA) was administered orally at doses of 12.5 to 50 mg/kg body weight twice or three times per day to a patient with mitochondrial encephalomyopathy associated with congenital lactic acidemia. During therapy, the rates of decarboxylation of (1-14C) pyruvate and (3-14C) pyruvate, which represent the activity of the pyruvate dehydrogenase (PDH) complex and the function of the TCA cycle, respectively, were markedly increased in the platelets and increases in the lactate levels in the blood and urine during exercise were markedly reduced. These results suggest that oral administration of DCA causes significant increases in the activities of the PDH complex and TCA cycle not only in the platelets but also in various tissues of humans, which is important as a pathway for production of energy, resulting in decreases in the lactate and pyruvate levels in the blood and cerebrospinal fluid.

Acetates↗
PubMed1989

[Evaluation of a rapid diagnosis of congenital lactic acidemia by transported peripheral blood samples].

The usefulness of a rapid diagnosis of congenital lactic acidemia was investigated using peripheral blood samples from 40 patients with lactic acidemia which had been transported from the hospitals in every part of Japan. Platelets and monocytes were separated, and the rates of decarboxylation of pyruvate and activities of enzymes involved in pyruvate metabolism were measured. The activity of phosphoenolpyruvate carboxykinase in monocytes was relatively stable. However, [1-14C] pyruvate and [3-14C] pyruvate decarboxylation rates and cytochrome c oxidase activity in platelets and pyruvate carboxylase activity in monocytes were unstable and decreased during the transportation of blood samples. Therefore, in order to diagnose the enzyme defects, it was necessary to compare the values for patients with those for control subjects who were simultaneously examined. Using this method, a patient with pyruvate dehydrogenase complex deficiency was found in the 40 patients with congenital lactic acidemia.

Acidosis, Lactic↗
PubMed1989

[The role of drugs and lymphocytes in granulocyte-macrophage colony formation in patients with drug induced agranulocytosis].

The in vitro effects of the causative drugs and lymphocytes from the patients with agranulocytosis were tested against granulocyte-macrophage colony formation (CFU-C) of bone marrow cells from normal individuals and the patients in recovery stage. A semisolid culture system was used for CFU-C assay. The drug concentrations were adjusted to the therapeutic levels in sera, and the lymphocytes were obtained from the patient's peripheral blood. Three patients with agranulocytosis and one patient with pancytopenia caused by disopyramide, methimazole, sodium valproate, and Towasaal, respectively, were examined. Each of the four drugs except disopyramide suppressed the CFU-C of normal and patient's bone marrow cells in a dose-dependent manner. When the patient's bone marrow cells were cultured with respective drugs and their own lymphocytes or with the culture supernatant of the drug and lymphocytes, CFU-C suppressions was significantly augmented. Phenacetin, an agent of Towasaal, significantly suppressed CFU-C and also CFU-E. These results indicate that humoral factor(s) produced from patient's lymphocytes by reacting with the drugs may function as an immunological mechanism in the patients with drug-induced agranulocytosis.

Adult↗
PubMed1988

Detection of pyruvate metabolism disorders by culture of skin fibroblasts with dichloroacetate.

For use in screening for disorders of pyruvate metabolism, a sensitive assay method was developed for measuring the rate of decarboxylation of [1-14C]pyruvate during in vitro culture of skin fibroblasts with dichloroacetate (DCA). The rate of decarboxylation of [1-14C]pyruvate by skin fibroblasts from control subjects increased from 59.6 +/- 13.2 to 97.3 +/- 12.0 nmol/h/mg protein during in vitro culture in medium supplemented with 10 mM DCA for 3 days. In contrast, the rate hardly increased in cells from four of 20 patients with congenital lactic acidosis of unknown cause during in vitro culture with DCA. On day 3 of culture, the values for the four patients did not overlap those of control cells and so these four patients could be clearly distinguished from control subjects. Measurements of the original activity and the activity of the pyruvate dehydrogenase (PDH) complex after activation with a broad specificity protein phosphatase and DCA suggested that in three of the patients the aberration was a disorder in the mechanism for activation of PDH, including deficiency of PDH phosphatase or a mutation of PDH itself, whereas that in the fourth patient it might be a disorder of the mitochondrial transport system for pyruvate. Thus, measurement of the rate of decarboxylation of [1-14C]pyruvate by skin fibroblasts cultured in medium supplemented with 10 mM DCA for 3 days is a useful method for screening for disorders of pyruvate metabolism in cultured skin fibroblasts.

Acetates↗