Search PubMed⌕ Search

Biomedical subjects

T Ariga

Publications and source records attributed to T Ariga.

At least 91 records · Page 5Linked to original sources

Unusual gangliosidosis in emu (Dromaius novaehollandiae).

A previous study has demonstrated an unusual gangliosidosis in emu that is characterized by the accumulation of gangliosides in the brain tissues with GM3 and GM1 predominating. To provide insight into this unique disorder of emu gangliosidosis, the current study focused on analysis of neutral glycosphingolipids and gangliosides from brain and liver tissues of affected birds and healthy controls. We found not only that the total lipid-bound sialic acid content was increased three- and fourfold in the affected brain and liver, respectively, but also that the ganglioside pattern was rather complex as compared with the control. The absolute ganglioside sialic acid content was significantly increased in the diseased tissues, with the highest elevation levels of GM3 (14-fold) and GM1 (ninefold) in the affected brain. Relative increases in content of these monosialogangliosides were also significant. GM2 was only detected in the affected brain, but not in normal controls. The neutral glycosphingolipid fraction showed accumulation of many oligosylceramides, with six- and 5.5-fold increases in lactosylceramide levels for brain and liver, respectively. The level of myelin-associated galactosylceramide (GalCer) in the brain was decreased to only 41% of that in the healthy control, whereas no difference was found in liver tissues from both groups. Besides GalCer, the brain content of sulfatide (cerebroside-sulfate esters), another myelin-associated glycolipid, decreased to only 16% of the control. The loss of myelin-associated GalCer and sulfatide strongly suggests demyelination in the affected emu brain. Our overall data are consistent with the presence of a unique form of sphingolipidosis in the affected emus, perhaps with secondary demyelination, and suggest a metabolic disorder related to total sphingolipid activator deficiency.

Animals↗

Extremely high serum level of IgE during immunosuppressive therapy: paradoxical effect of cyclosporine A and tacrolimus.

A case of X-linked autoimmune enteropathy was successfully treated with cyclosporine A (CsA) or tacrolimus (FK506) and developed extremely high serum levels of IgE during the immunosuppressive therapy. Serum IgE levels increased from 190 to 1,000-2,500 IU/ml with CsA therapy and as high as 80,000 IU/ml with subsequent FK506 therapy. Serum IgG2 and IgG4 levels were slightly elevated compared to serum IgE levels. Thereafter, serum IgE levels progressively decreased in parallel with a reduced dosage of FK506. Total serum IgG levels and peripheral eosinophil counts, however, showed no significant changes during the course. These observations suggest that both CsA and FK506, potent immunosuppressants, could paradoxically enhance some immune responses, possibly through the action of CsA-/FK506-resistant immune systems.

Anemia, Hemolytic↗

Mutation analysis of five Japanese families with Wiskott-Aldrich syndrome and determination of the family members' carrier status using three different methods.

Mutation analysis for five families with Wiskottt-Aldrich syndrome was performed. The mutations found were two missense mutations, two one-base deletion mutations, and a large deletion mutation in the WASP gene. The three mutations had been reported before, but the remaining two were new. We used the mutation information to determine the carrier status of the female relatives of the patients. Three different approaches were taken depending on the type of mutation, and the carrier determination was successfully performed.

Adult↗

Antibodies to glycosphingolipid antigens in patients with immune-mediated cochleovestibular disorders.

HYPOTHESIS: To determine the presence of antibodies against the glycosphingolipid antigen sulfated glucuronic lactosominyl paragloboside (SGLPG) in the sera of patients suspected of immune-mediated cochleovestibular disorders (IMCVD). BACKGROUND: Glycospingolipids are molecules present on the surface of normal nerve cells and are considered antigenic. Previous studies have isolated these antigens in vestibular neuroepithelia, cochleovestibular nerves and endolymphatic sacs. METHODS: The sera of 22 patients suspected of IMCVD were tested for antibodies against the antigen SGLPG. Thin-layer chromatography-immunostaining method was used. RESULTS: Antibody titers were elevated in 63.6% of patients tested. Statistical significance (p < 0.0001) was achieved since reactivity was seen in only 7% of 43 age-matched healthy controls. CONCLUSIONS: Antibodies to SGLPG antigens are present in some patients with IMCVD. Because SGLPD antigens have been previously isolated in the inner ear and the cochleovestibular nerve, these structures can potentially become targets for anti-SGLPG antibodies.

Adult↗

[The relation between pyrimidine nucleoside phosphorylase (PyNPase) activity in colorectal cancer tissues and pathological effects].

Pyrimidine nucleoside phosphorylase (PyNPase) and IL-1 alpha concentration were measured in colorectal cancer tissues from 15 patients who preoperatively administered 5'-DFUR orally. The relation between changes of the PyNPase activity and pathological effects of resected specimens was studied. PyNPase activity changes showed that the increase cases were 9 patients and the decrease cases were 6 patients in pre- and post-administration of 5'-DFUR. The IL-1 alpha concentration in cancer tissues was 2933.65 +/- 2038.65 in the decrease cases and 1207.51 +/- 1378.83 in the increase cases. The level was significantly higher in the decrease case (p < 0.05). And there tended to be more pathologically effective in the decrease cases than in increase cases. The effects of preoperative oral chemotherapy in colorectal cancer was strongly influenced by changes of PyNPase activity and IL-1 alpha concentration in tumor tissues.

Administration, Oral↗

[The gene therapy for a patient with ADA deficiency; report of the first gene therapy trial in Japan].

Since the first gene therapy clinical trial for an ADA deficient patient was performed in September 1990, 10 ADA deficient patients have been enrolled in gene therapy clinical trial. We have been performing the first gene therapy trial in Japan for a 5 year boy with ADA deficiency since August 1995. Activated T cells from the patient's peripheral mononuclear cells were transduced by a retrovirus vector, LASN, which contained cDNA of human ADA gene, and re-infused to him intravenously after 7-11 days. We have already performed 10 cycles of the therapy for the patient. Here, we report the successful results of the gene therapy with laboratory and clinical evaluation. Furthermore, we overview the results of gene therapy for ADA deficient patients which were recently reported from 4 other groups.

Adenosine Deaminase↗

Detection of human herpesvirus 8 DNA sequences in peripheral blood mononuclear cells of children.

Human herpesvirus 8 (HHV-8) DNA sequences were examined in peripheral blood mononuclear cell (PBMC) DNA samples of 56 children, 15 healthy adults, and 10 renal transplant patients by the polymerase chain reaction (PCR). The PCR amplification was carried out using the published KS330(233) primer pairs to amplify HHV-8 DNA sequences. The PCR-amplified products were confirmed by Southern blot hybridization with radiolabeled 233 bp HHV-8 DNA fragment, which was cloned and sequenced from the PCR-amplified product of Kaposi's sarcoma tissue. Six PCR-amplified product of four children and two renal transplant patients were cloned and sequenced. HHV-8 DNA sequences were detected in 36 of 56 (64%) normal children, in 12 of 15 (80%) healthy adults, and in all 10 renal transplant patients by Southern blot hybridization of PCR-amplified products. Six PCR-amplified products were confirmed by sequencing. These results suggest that HHV-8 infection is prevalent in the Japanese population with infection occurring in early childhood.

Adult↗

[Hepatectomy and intra-arterial infusion chemotherapy for hepatic metastasis of colorectal cancer].

We experienced 339 patients with primary colorectal cancer in our department. In the present study 69 cases of liver metastasis were examined for their treatments and effects. One-year, 3-year and 5-year survival rates were 49.2%, 16.2% and 6.8% in the 69 patients, respectively. Fourteen patients underwent hepatic resection plus hepatic artery infusion therapy. The overall survival rates at 1, 3 and 5 years were favorable: 88.3%, 55.6% and 29.6%, respectively. Three patients with H3 liver metastasis underwent hepatic resection plus hepatic artery infusion therapy. One patient is alive 29 months after operation, one died 25 months after operation, and the other is alive 8 months after operation. Thirteen patients with H3 liver metastasis from colorectal cancer underwent hepatic artery infusion therapy, and the one-year survival rate was 30.8%. None of the H3 patients without hepatic artery infusion therapy survived more than one year.

Antimetabolites, Antineoplastic↗

Detection of a novel splice-site mutation that results in skipping exon 3 of the WASP gene in a patient with Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is one of the primary immunodeficiency diseases, that is inherited as an X-linked recessive trait. Since the responsible gene, the WASP gene, has been identified, various mutations for patients with WAS have been reported. We found a novel splice-site mutation in a patient with clinically diagnosed WAS. The mutation was a replacement of ag by aa in an acceptor site of intron 2 of the WASP gene. Sequencing studies of the WASP cDNA of the patient revealed that exon 3 of the WASP gene was abnormally missing due to a splicing defect.

Exons↗

Molecular cloning of cDNA for rat brain GD3-synthase.

The complete nucleotide sequence of the cDNA coding for rat GD3-synthase was determined for the first time using PCR and the rapid amplification of cDNA ends (RACE) procedures. The deduced amino acid sequence consists of 359 residues. The protein contains a potential transmembrane domain with a short N-terminus and such highly conserved regions as the sialylmotifs. An antisense oligonucleotide derived from the rat GD3-synthase cDNA was applied to the cultures of rat cerebellar neurons and results showed a decrease in the synthesis of ganglioside GD3, indicating that the expression of GD3-synthase was modulated by the antisense sequence.

Amino Acid Sequence↗

Generation and characterization of anti-sulfoglucuronosyl paragloboside monoclonal antibody NGR50 and its immunoreactivity with peripheral nerve.

Sulfoglucuronosyl paragloboside (SGPG) is a member of the sulfated glucuronic acid-containing glycolipid (SGGL) family found primarily in peripheral nerves. These glycolipids contain the HNK-1 carbohydrate epitope and are recognized by monoclonal IgM from patients with chronic demyelinating neuropathy and paraproteinemia. Recent studies indicate that SGGLs may serve as ligands for selectins, amphoterin, and laminin, suggesting that these glycolipids may play an important role in cellular adhesion. To elucidate the biological function of these glycolipids, we produced a murine monoclonal antibody (mAb) and studied its antigenic specificity. Using an enzyme-linked immunosorbent assay (ELISA), we found that the mAb designated as NGR50 belonged to the IgG2a subclass, and that the minimal titer (2 SD above the mean optical density value of control) of this mAb was 1:640, with 20 ng of purified SGPG as the antigen. Thin-layer chromatography (TLC) immunoblotting revealed that this mAb reacted specifically with SGPG and sulfoglucuronosyl lactosaminyl paragloboside (SGLPG), which is a structural analogue of the former, but not with other glycolipids. Desulfated derivates of SGPG and SGLPG did not react with mAb NGR50. Western blot analysis showed crossreactivity with human myelin-associated glycoprotein (MAG), but not with rat MAG or rat glycoprotein P0. Unlike anti-HNK-1 monoclonal antibody, however, NGR50 reacted only weakly with several proteins in the 20-30-kD regions, including human P0, suggesting that mAb50 has a different fine specificity as an anti-HNK-1 antibody. Immunocytochemical study of rat sciatic nerve using mAb NGR50 revealed positive staining at the outer surface of the myelin sheath and Schwann cells, as well as in the intervening connective tissues. Faint staining was also visible at the axolemmal-myelin interface; however, compact myelin was not stained.

Animals↗

Sensitization of Lewis rats with sulfoglucuronosyl paragloboside: electrophysiological and immunological studies of an animal model of peripheral neuropathy.

Antibodies against sulfoglucuronosyl glycosphingolipids (SGGLs) are known to be present in sera of patients with chronic polyneuropathy associated with IgM paraproteinemia. We recently studied rats sensitized with sulfoglucuronosyl paragloboside (SGPG), a major SGGL species, emulsified with keyhold limpet hemocyanin and Freund's adjuvant. The titer of the IgM class antibodies against SGPG increased up to 1:1,600, while that of the IgG class increased up to 1:800 2 weeks after sensitization. The antibodies showed a high degree of antigenic specificity; no cross-reactivity with other brain glycolipids could be detected. They, however, reacted with human myelin-associated glycoprotein (MAG) by Western blot analysis, but not with rat MAG. These animal models showed minor but clear clinical signs of neuropathy, consisting of mild tail muscle tone loss and walking disabilities. Electrophysiological examination of the sciatic nerves revealed nerve conduction abnormalities which consisted of conduction block and mild decrease in conduction velocity. Thus, our results support the concept that anti-SGPG antibodies may play an important pathogenetic role in this type of chronic neuropathy.

Action Potentials↗

Expression and localization of Lewis(x) glycolipids and GD1a ganglioside in human glioma cells.

We analysed the glycolipid composition of glioma cells (N-370 FG cells), which are derived from a culture of transformed human fetal glial cells. The neutral and acidic glycolipid fractions were isolated by column chromatography on DEAE-Sephadex and analysed by high-performance thin-layer chromatography (HPTLC). The neutral glycolipid fraction contained 1.6 micrograms of lipid-bound glucose/galactose per mg protein and consisted of GlcCer (11.4% of total neutral glycolipids), GalCer (21.5%), LacCer (21.4%), Gb4 (21.1%), and three unknown neutral glycolipids (23%). These unknown glycolipids were characterized as Lewis(x) (fucosylneolactonorpentaosyl ceramide; Le(x)), difucosylneolactonorhexaosyl ceramide (dimeric Le(x)), and neolactonorhexaosyl ceramide (nLc6) by an HPTLC-overlay method for glycolipids using specific mouse anti-glycolipid antibodies against glycolipid and/or liquid-secondary ion (LSI) mass spectrometry. The ganglioside fraction contained 0.6 micrograms of lipid-bound sialic acid per mg protein with GD1a as the predominant ganglioside species (83% of the total gangliosides) and GM3, GM2, and GM1 as minor components. Trace amounts of sialyl-Le(x) and the complex type of sialyl-Le(x) derivatives were also present. Immunocytochemical studies revealed that GD1a and GalCer were primarily localized on the surface of cell bodies. Interestingly, Le(x) glycolipids and sialyl-Le(x) were localized not only on the cell bodies but also on short cell processes. Especially, sialyl-Le(x) glycolipid was located on the tip of fine cellular processes. The unique localization of the Le(x) glycolipids suggests that they may be involved in cellular differentiation and initiation of cellular growth in this cell line.

Animals↗

Expression of a unique globo-series glycolipid in cultured rat dorsal root ganglion neurons: relationship with neuronal development.

Previous studied from the laboratory demonstrated the presence of a UDP-galactose:Gb3Cer alpha 1-3galactosyltansferase activity responsible for the synthesis of a unique glycosphingolipid (GSL), Gal alpha 1-3Gb3Cer, in cultured PC12 pheochromocytoma cells (21). In this investigation, we examined the presence of this enzyme activity in isolated rat embryonic dorsal root ganglion neurons (DRGN), which, like pheochromocytoma cells, originate from the neural crest cells. DRGN exhibited the alpha-galactosyltransferase activity and the activity was comparable to that of the PC12 cells while several other rat tissues, with the exception of kidney, showed minimal activity. In order to define the spatial and temporal expression of Gal alpha 1-3Gb3Cer in DRGN, we examined the expression of Gal alpha 1-3Gb3Cer in cultured DRGN derived from embryonic day 16 rat embryos. Using a polyclonal antibody raised against Gal alpha 1-3Gb3Cer, we examined the localization of this glycolipid in DRGN cells after 5, 8, 12, and 15 days in culture. Immunostaining was restricted to the neurons while Schwann cells were negative. At day 5, the immunostaining was weak and confined to the cell body of the DRGN, though neurites were present at this stage. The period between days 5 and 15 represented a period of rapid neuritic growth and continued enlargement of the cell bodies. Immunoreactivity in the cell bodies increased dramatically by day 8. By day 12, immunoreactivity was present in neurites, and by day 15, was strong in both cells bodies and neurites. The expression of Gal alpha 1-3Gb3Cer in vivo was confirmed by immunostaining of frozen sections of dorsal root ganglia. Our present studies which demonstrate neuron-specific expression of Gal alpha 1-3Gb3Cer during neurotigenesis combined with previous observations for its expression in PC12 cells, strongly implicates this GSL in neuronal development.

Animals↗

Production of tissue-type plasminogen activator (t-PA) and type-1 plasminogen activator inhibitor (PAI-1) in mildly cirrhotic rat liver.

We have studied the production of tissue-type plasminogen activator (t-PA) and type-1 plasminogen activator inhibitor (PAI-1) in liver of normal rats and in rats with mild cirrhosis induced by carbon tetrachloride inhalation, to demonstrate the production of these fibrinolytic components and their pathophysiologic role in the liver in vivo. Immunohistochemical study of paraffin-embedded liver sections and fibrin autography of frozen sections showed that the normal rat liver produces very little t-PA or PAI-1. On the contrary, striking t-PA activity and both t-PA and PAI-1 antigens were observed in the cirrhotic liver. Both t-PA and PAI-1 in plasma were also markedly increased in the cirrhotic rats. Because the hepatocyte can internalize t-PA or PA/PAI-1 complexes from circulation, Northern blot analysis of the total liver RNA was performed to demonstrate the endogenous synthesis of t-PA and PAI in the liver. Although the normal liver hardly expresses either t-PA or PAI-1 mRNA, striking t-PA and PAI-1 mRNA expression was observed in the liver of rats with mild cirrhosis. These data demonstrate that t-PA and PAI-1 production is strongly upregulated in the liver in rats with mild cirrhosis. These fibrinolytic components, whose production is closely associated with liver failure, may play important roles in the regulation of hepatocyte proliferation and liver regeneration in vivo.

Animals↗

Glycosphingolipid composition of murine neuroblastoma cells: O-acetylesterase gene downregulates the expression of O-acetylated GD3.

We have studied the glycosphingolipid composition in an F-11 neuroblastoma cell line originated from hybridization of a mouse neuroblastoma cell line (N18TG-2) with rat dorsal root ganglion cells. The total lipid-bound glucose of F-11 cells was estimated to be 0.28 micrograms/mg of protein and the total lipid-bound sialic acid was 0.82 micrograms/mg of protein. The major neutral glycosphingolipids were Gb4 (37% of the total neutral glycosphingolipids), Gb3 (15%), LacCer (21%), and GlcCer (15%). The major gangliosides were found to be GM3 (37% of the total gangliosides), GD3 (27%), O-acetylated GD3 (18%), and GD1a (4%), with trace amounts of GD2. The unusually high concentration of O-acetylated GD3 is consistent with its putative role as a tumor marker. Immunocytochemical localization studies of GD3 and O-acetylated GD3, examined by mouse monoclonal antibodies R24 and D1.1, respectively, revealed that the cell bodies and processes were all positively stained. To elucidate the role of O-acetylated GD3 in tumorigenesis, we transfected F-11 cells with the O-acetylesterase gene from influenza C virus. Compared with the original cell line, the transfected cells showed a dramatic increase in the level of GD3 (150% of that in the control cells) and a significant decrease of the concentration of O-acetylated GD3 (27% of control cells). In addition, the transfected F-11 cells exhibited a morphology different from the parental cells with enlarged cell bodies and elongated neurites. We conclude that alteration of ganglioside composition, particularly the expression of GD3 and O-acetylated GD3, may be associated with the morphological changes observed in this cell line.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylation↗