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Biomedical subjects

T Kasama

Publications and source records attributed to T Kasama.

At least 91 records · Page 5Linked to original sources

Enzymatic inactivation of leukotriene B4 by a novel enzyme found in the porcine kidney. Purification and properties of leukotriene B4 12-hydroxydehydrogenase.

Leukotriene B4 (LTB4) 12-hydroxydehydrogenase was purified to apparent homogeneity from the cytosol fraction of the porcine kidney. The N-terminal amino acid sequence analysis revealed that this enzyme is a novel protein with a molecular weight of 35,000. Although the enzyme is ubiquitously distributed in various tissues and leukocytes of porcine, the kidney and liver had the highest enzyme activities. In the presence of NADP+ as a cofactor, the enzyme catalyzes the conversion of LTB4 to 12-oxo-LTB4, the structure identified by gas chromatography/mass spectrometry. 12-Oxo-LTB4 was further converted by other enzymes to 10,11,14,15-tetrahydro-12-oxo-LTB4, which was determined by proton NMR and gas chromatography/mass spectrometry. 12-Oxo-LTB4 was 100-fold less potent than LTB4 in increasing intracellular calcium concentrations of human leukocytes. 6-trans-LTB4 and LTB4 proved to be the best substrates of the enzyme, whereas various types of monohydroxyeicosatetraenoic acids, 5(S),12(S)-dihydroxyeicosatetraenoic acid, prostaglandins, cortisol, or pregnenolone could not serve as a substrate. These results suggest that the enzyme acts specifically on the 12(R)-hydroxy group of leukotriene B4 and is involved in the metabolic inactivation of LTB4 in the porcine kidney.

Alcohol Oxidoreductases↗

Expression and regulation of human neutrophil-derived macrophage inflammatory protein 1 alpha.

Neutrophil (polymorphonuclear leukocyte [PMN]) sequestration is one of the histologic hallmarks of an acute inflammatory response. During the natural evolution of an inflammatory response, PMNs are often replaced by mononuclear cells. This shift in the elicitation of specific leukocyte populations usually occurs as the inflammatory lesion enters either the repair/resolution stage or progresses to a chronic inflammation. To elucidate a potential mechanism for the temporal change from predominantly PMN recruitment to the presence of monocytes, we postulated that PMNs could be a rich source of monocyte chemotactic factors. In our studies, we have identified a dose-dependent induction of monocyte chemotactic activity by PMNs treated with lipopolysaccharide (LPS; 1-100 ng/ml). Interestingly, this monocyte chemotactic activity was significantly attenuated in the presence of neutralizing anti-human macrophage inflammatory protein 1 alpha (MIP-1 alpha) antibodies. Moreover, immunolocalization studies demonstrated the expression of MIP-1 alpha by stimulated PMNs. These findings showed that a significant amount of PMN-derived monocyte chemotactic activity was attributable to MIP-1 alpha. Subsequent characterization of MIP-1 alpha steady-state mRNA and antigen expression demonstrated both a dose- and time-dependent production by LPS-treated PMNs. Granulocyte/macrophage colony-stimulating factor (GM-CSF), a potent PMN activator, failed to induce the expression of MIP-1 alpha over a wide range of concentrations. However, PMNs stimulated in the presence of both LPS and GM-CSF resulted in a synergistic expression pattern for MIP-1 alpha. PMNs stimulated in the presence of both GM-CSF and LPS demonstrated an enhanced and prolonged expression for both MIP-1 alpha mRNA and antigen, as compared with LPS alone. Messenger RNA stabilization analyses demonstrated that MIP-1 alpha mRNA isolated from PMNs stimulated in the presence of GM-CSF and LPS had a prolonged mRNA t1/2, as compared with LPS alone. These findings support the notion that PMNs are capable of producing MIP-1 alpha in the presence of LPS, and that GM-CSF can influence this production through prolongation of MIP-1 alpha mRNA t1/2. The production of PMN-derived MIP-1 alpha, in association with the expression of appropriate adhesion molecules at a site of inflammation, may be one of the central events that contributes to the temporal shift from predominantly PMNs to monocytes during the evolution of inflammation.

Base Sequence↗

Glycosphingolipid compositions of human T-lymphotropic virus type I (HTLV-I) and human immunodeficiency virus (HIV)-infected cell lines.

Glycolipid compositions of cells infected by human retroviruses (human immunodeficiency virus, HIV and/or human T-cell lymphotropic virus type I, HTLV-I) have been studied. Eight cell lines, comprising two HTLV-I-infected T-cell lines (MT-2 and MT-4), two HTLV-I-negative T-cell lines (Jurkat and MF), a macrophage cell line (U937), and three HIV-infected counterpart cell lines (MT-4/HIV, Jurkat/HIV and U937/HIV) were used. The neutral glycolipids and gangliosides isolated from these cell lines were compared. Among them, the HTLV-I-infected T-cell lines, MT-2 and MT-4, showed similar patterns for both neutral glycolipids and gangliosides. Neutral glycolipids (GlcCer and LacCer) of MT-2 and MT-4 cells were markedly decreased, and a ganglioside, GM3, of theirs was decreased to only a trace amount compared to that in other cell lines. Gangliosides of MT-4 and MT-4/HIV were further separated on an Iatrobeads column, and were identified as GM2, GM1a and GD1a by methylation and liquid secondary ion mass spectrometric analyses. Since the patterns of neutral glycolipids and gangliosides of MT-2 and MT-4 are unique, as compared to those of HTLV-I-negative cells, it is suggested that these changes are related to HTLV-1 infection. No prominent differences in the ganglioside compositions between HIV-infected and non-infected cell lines could be observed. But it is noteworthy that the contents of asialo-GM2 in Jurkat/HIV and MT-4/HIV cells were increased as compared to those in the parental cell lines.

Carbohydrate Sequence↗

A novel polymorphism of human serum amyloid A protein, SAA1 gamma, is characterized by alanines at both residues 52 and 57.

We have identified a hitherto unknown polymorphism of serum amyloid A protein (SAA) in the pooled serum of nonamyloidotic inflammatory patients. The molecular weight of the novel SAA determined by ion-spray mass spectrometry appeared 28 amu lower in mass than the known SAA1 subsets, indicating that the substitution of a valine residue by an alanine was present. Further analyses by the combination of liquid chromatography/fast atom bombardment mass spectrometry, collision-activated dissociation mass spectrometry, and amino acid analysis revealed that this novel SAA, designated SAA1 gamma, has alanines at both residues 52 and 57 while the two known SAA1 subsets have a valine at either residue 52 or 57. Furthermore, des-1 Arg and des-1 Arg-2Ser forms of SAA1 gamma as well as those of the known SAA1 subsets were identified. This indicated that the common modification must have occurred at the N-termini of all SAA1 subsets. The existence of this SAA1 gamma had been suggested from one of the two novel AA proteins that we recently found (Baba, S. et al., 1992, Biochim. Biophys. Acta, 1180, 195-200).

Alanine↗

Fucosyl-GM1 in human sensory nervous tissue is a target antigen in patients with autoimmune neuropathies.

Several gangliosides of human nervous tissues have been reported to be potential target antigens in autoimmune neuropathies. To explain the diversity of clinical symptoms in patients with antiganglioside antibodies, we have searched for ganglioside antigens that are specific to individual nervous tissues such as motoneurons, peripheral motor nerves, and sensory nerves. Although the major ganglioside compositions were not different among human peripheral motor and sensory nerves, fucosyl-GM1 was found to be expressed in sensory nervous tissue but not in spinal cord, motor nerve, and sympathetic ganglia. Sera from several patients with sensory nerve involvement also reacted with fucosyl-GM1 as well as GM1. Thus, fucosyl-GM1 may be a responsible target antigen for developing sensory symptoms in some patients with autoimmune neuropathies.

Animals↗

Less polar glycolipids in Alaskan pollack brain: isolation and characterization of acyl galactosyl diacylglycerol, acyl galactosyl ceramide, and acyl glucosyl ceramide.

We recently reported that glycolipid compositions of gadoid fish nerve tissues are unique in the abundance of 1) galactosyl diacylglycerol and its sulfate ester; 2) glucosyl ceramide; and 3) fatty acid ester of cerebroside (J. Lipid Res. 1992. 33: 1351-1359). The present paper reports the characterization of less polar glycolipids isolated from Alaskan pollack brain. Of twelve glycolipids purified by column chromatography, four were of the galactosyl diacylglycerol type. Chemical analysis, infrared spectrometry, and a permethylation study followed by gas chromatography-mass spectrometry revealed that they were 1,2-di-O-acyl-3-beta (6-O-acyl-D-galactopyranosyl)-sn-glycerol and 1,2-di-O-acyl-3-beta(2'-O-acyl-D-galactopyranosyl)-sn-glycerol, and mixtures of these two isomers, with slightly different fatty acid compositions, respectively. The other eight less polar glycolipids were pure forms or mixtures of isomeric forms of cerebroside fatty acid esters in which the substituted position of the acyl group on the hexose moiety varied. The permethylation study revealed that they were 6-O-acyl-beta-D-galactopyranosyl, 6-O-acyl-beta-D-glucopyranosyl, 2-O-acyl-galactosyl, 2-O-acyl-glucosyl, 3- or 4-O-acyl-galactosyl, and 3-O-acyl-glucosyl ceramides, the 6-O- and 2-O-acyl isomers being predominant. This is the first report of the natural occurrence of 1) acyl galactosyl diacylglycerol in animal tissues and 2) acyl glucosyl ceramide in nerve tissues.

Animals↗

Identification of two novel amyloid A protein subsets coexisting in an individual patient of AA-amyloidosis.

Amyloid A protein (AA), the major fibril protein in AA-amyloidosis, is an N-terminal cleavage product of the precursor protein, serum amyloid A (SAA). Using mass spectrometry and amino-acid sequencing, we identified and characterized two novel AA protein subsets co-deposited as amyloid fibrils in an patient having AA-amyloidosis associated with rheumatoid arthritis. One of the AA proteins corresponded to positions 2-76 (or 75) of SAA2 alpha and the other corresponded to positions 2-76 (or 75) of known SAA1 subsets, except for position 52 or 57, where SAA1 alpha has valine and alanine and SAA1 beta has alanine and valine in position 52 and 57, respectively, whereas the AA protein had alanine at the both positions. Our findings (1), demonstrate that not only one but two SAA subsets could be deposited together as an AA-amyloid in a single individual and (2), support the existence of a novel SAA1 allotype, i.e., SAA152,57Ala.

Alanine↗

Isolation and structural characterization of a mono-sulfated isoglobotetraosylceramide, the first sulfoglycosphingolipid of the isoglobo-series, from rat kidney.

A novel sulfoglycosphingolipid based on the isoglobo-series core structure was isolated from rat kidney and purified by column chromatographies with DEAE-Sephadex and silica beads. The structure was characterized by solvolysis, compositional analysis, proton NMR spectroscopy, Fourier-transform infrared spectroscopy, methylation analysis and liquid secondary ion mass spectrometry (LSIMS). The characteristic fragment ions for a sulfate and a sulfated N-acetylhexosamine were observed in LSIMS spectra. The two-dimensional chemical-shift-correlated spectroscopy (COSY) and nuclear Overhauser enhancement spectroscopy experiments evidenced the presence of a 3-O-sulfated N-acetylgalactosamine and a Gal alpha 1-3Gal structure in the molecule. The major ceramide consisted of 4-hydroxysphinganine linked to a C24 nonhydroxy fatty acid, deduced from both compositional analysis and LSIMS. From the above results, the following structure was established for this glycolipid: HSO3-3GalNAc beta 1-3Gal alpha 1-3Gal beta 1-4Glc beta 1-1Cer, isoglobotetraosylceramide (iGb4Cer) IV3-sulfate. Rat kidney also contained globotetraosylceramide (Gb4Cer) IV3-sulfate which has a carbohydrate core identical to that from human kidney. The yields of iGb4Cer IV3-sulfate and Gb4Cer IV3-sulfate were 0.27 and 0.07 nmol/g wet tissue, respectively.

Animals↗

Human hepatoma gangliosides: occurrence of a novel I-type glycolipid with NeuAc alpha 2-6Gal structure.

Gangliosides with NeuAc alpha 2-6Gal structure have been studied in human hepatocellular carcinoma. The gangliosides were purified to homogeneity by a DEAE-Sephadex A-25 column chromatography and by repeated silica beads column chromatography. Three gangliosides containing NeuAc alpha 2-6Gal structure were isolated and were structurally characterized by using monoclonal antibodies, proton nuclear magnetic resonance, fast atom bombardment mass spectrometry, methylation analysis by gas chromatography-mass spectrometry, and exoglycosidase treatments. The first compound was identified as NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer. The structures of 2 other components were concluded to be as follows: [formula: see text] The first compound is a ganglioside that is characteristic of human meconium. The second compound has the same structure as a ganglioside recently found by us (Taki, T., Rokukawa, C., Kasama, T., Kon, K., Ando, S., Abe, T., and Handa, S., J. Biol. Chem., 267: 11811-11817, 1992) in meconium. The third compound is a novel type of ganglioside having blood group I-type structure as the core sequence. In addition to these gangliosides, 5 others were detected, and all except for GM3 were glycolipids with neolacto-series core structure. These results suggest that enzymes for the synthesis of neolacto type and NeuAc alpha 2-6Gal structure of glycolipids are activated in hepatoma.

Antibodies, Monoclonal↗

Identification of 7 alpha-hydroxy-3-oxo-4-cholestenoic acid in chronic subdural hematoma.

We detected a novel kind of bile acid in the content of chronic subdural hematoma. This substance was specifically found in chronic subdural hematoma, and not in subdural hygroma, which is pathologically similar except for the lack of capsular membrane. The compound was identified as 7 alpha-hydroxy-3-oxo-4-cholestenoic acid by high performance liquid chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectrometry. The structure was confirmed by the comparison with the chemically synthesized compound. The average contents in chronic subdural hematoma were 658.09 +/- 137.53 ng/ml, while those in normal human plasma were 126.27 +/- 17.73 ng/ml. It was not detected in normal cerebrospinal fluid. The higher level in chronic subdural hematoma than human plasma strongly suggests the local, extrahepatic production of this type of C27 bile acids.

Bile Acids and Salts↗

Human meconium gangliosides. Characterization of a novel I-type ganglioside with the NeuAc alpha 2-6Gal structure.

Three monosialogangliosides containing the NeuAc alpha 2-6Gal structure have been detected in human meconium by immunological analysis using a monoclonal antibody, MSG-15, and purified by repeated silica beads column chromatography. One was previously shown to be NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer. The remaining two were characterized by proton NMR, fast atom bombardment mass spectrometry, methylation analysis by gas chromatography-mass spectrometry, and immunological studies, and their structures were concluded to be as follows. [formula: see text] The second ganglioside has the same structure that was isolated from bovine buttermilk (Takamizawa, K., Iwamori, M., Mutai, M., and Nagai, Y. (1986) J. Biol. Chem. 261, 5625-5630), and this is the first description of the occurrence of the ganglioside with the branched structure with two N-acetyllactosamines linked to lactosylceramide via beta 1-6 and beta 1-3 in human linked to lactosylceramide via beta 1-6 and beta 1-3 in human tissues. The third ganglioside is a novel ganglioside with blood group I-type and a NeuAc alpha 2-6Gal structure.

Amino Sugars↗

Suppression of pulmonary granulomatous inflammation by immunomodulating agents.

We demonstrated previously that macrophages and macrophage-derived cytokines including lymphocyte-activating factors (LAFs) play a critical role in lung granuloma formation in mice and that granulomas sizes correlated with LAF activity in the lesions. In the present study, we examined the effects of D-penicillamine (D-Pc), 2-acetylthiomethyl-3-(4-methyl-benzoyl)propionic acid (KE-298) and dexamethasone (Dex) on dextran bead-induced lung granulomas in mice. KE-298 is a newly synthesized compound containing sulfur (S) similar to D-Pc. Large granulomas developed, which reached peak intensity within 3 days and declined in size thereafter. Aqueous lung extracts of the mice contained high levels of LAF that were correlated with granuloma sizes. The lesions and local LAF activity were inhibited by administration of these agents. The most potent inhibitor was Dex. The suppressive effect of KE-298 was similar to that of D-Pc. These results suggest that suppression of granulomas may be attributed to inhibition of LAF activity/synthesis by these agents.

Animals↗

Isolated bovine spinal motoneurons have specific ganglioside antigens recognized by sera from patients with motor neuron disease and motor neuropathy.

The gangliosides GM1 and GD1b have recently been reported to be potential target antigens in human motor neuron disease (MND) or motor neuropathy. The mechanism for selective motoneuron and motor nerve impairment by the antibodies directed against these gangliosides, however, is not fully understood. We recently investigated the ganglioside composition of isolated bovine spinal motoneurons and found that the ganglioside pattern of the isolated motoneurons was extremely complex. GM1, GD1a, GD1b, and GT1b, which are major ganglioside components of CNS tissues, were only minor species in motoneurons. Among the various ganglioside species in motoneurons, several were immunoreactive to sera from patients with MND and motor neuropathy. One of these gangliosides was purified from bovine spinal cord and characterized as N-glycolylneuraminic acid-containing GM1 [GM1(NeuGc)] by compositional analysis, fast atom bombardment mass spectra, and the use of specific antibodies. Among seven sera with anti-GM1 antibody activities, five sera reacted with GM1(NeuGc) and two did not. Two other gangliosides, which were recognized by another patient's serum, appeared to be specific for motoneurons. We conclude that motoneurons contained, in addition to the known ganglioside antigens GM1 and GD1b, other specific ganglioside antigens that could be recognized by sera from patients with MND and motor neuropathy.

Animals↗

Augmentation of pulmonary foreign body granulomatous inflammation in mice by lipopolysaccharide: involvement of macrophage activation and tumor necrosis factor-alpha.

We examined the effect of lipopolysaccharide (LPS) on dextran bead-induced lung granulomas using LPS responder (C3H/HeN) and nonresponder (C3H/HeJ) mice. LPS augmented granuloma sizes, TNF-alpha and N-acetyl-beta-D-glucosaminidase levels of lung extracts in C3H/HeN, but not in C3H/HeJ mice. Granuloma macrophages of C3H/HeN mice produced higher levels of superoxide anion and TNF-alpha than those of C3H/HeJ mice. Taken together with our previous report that macrophages and macrophage-derived cytokines are essential for the development of lesions, the present results suggest that activation of macrophages plays an important role in the development and augmentation of pulmonary granulomas.

Acetylglucosaminidase↗

[Lung injury associated with bucillamine therapy].

We have reported previously a first case of interstitial pneumonitis in rheumatoid arthritis treated with bucillamine in 1989. Thereafter, a dozen cases with lung injury associated with bucillamine therapy have been reported. To explore the similarities among these patients, we tried to carry out a survey concerning the lung injuries in these cases in the present study. We obtained the following results. (1) Patients with lung injury consisted of 7 females and 3 males, aged 65 years on average (59-72). (2) The total amount of bucillamine used was 20-40 g on average (5.1-144 g) during approximately 100 days. (3) Serum rheumatoid factor was positive in 9 of 10 cases. (4) HLA-DR4 was significantly (p less than 0.01) detected in all cases of lung injury associated with bucillamine. (5) Interestingly the effect of bucillamine on rheumatoid disease activity was excellent in most cases. (6) Drug lymphocyte stimulation test (DLST) using bucillamine was performed in 6 cases. Positive DLST was found in 3 of 6 cases. These results suggest that cell-mediated hypersensitivity reaction (Coombs & Gell type IV) may contribute to the development of lung injury associated with bucillamine therapy.

Aged↗

Effects of cholestanol feeding on corneal dystrophy in mice.

A cholestanol-enriched diet administered for 8 months to BALB/c mice produced in 20% two kinds of corneal opacities resembling calcific band keratopathy and Schnyder's crystalline dystrophy in humans. The concentrations of cholestanol in serum, liver and cornea of the corneal opacity bearing mice were 30-40-times higher than those of normal mice. On the other hand, brain cholestanol level increased only 7-times in the opacity group as compared with that of control group. There was no significant difference in the cholesterol concentrations of serum and several tissues among opacity, non-opacity and the control group. The crystal particles were observed between epithelial basement membrane and superficial stroma by the electron microscopy. Energy dispersive analysis of the particles revealed that the deposits were composed principally of calcium and phosphorus with other crystalline materials, which was presumed to be cholestanol. These results suggest that the cholestanol may deposit in the cornea from elevated serum levels. Deposition of cholestanol in cornea and related area may be a cause of corneal dystrophy in CTX.

Animals↗

Structural studies of gangliosides by fast atom bombardment ionization, low-energy collision-activated dissociation, and tandem mass spectrometry.

Negative ion fast atom bombardment, low-energy collision-activated dissociation, and tandem mass spectrometry techniques were applied for the structural elucidation of gangliosides. The mass spectra were simplified by selecting a single molecular ion or fragment ion in the analysis of mixtures, and interference by background signals from the liquid matrix could be avoided. Introduction of collision-activated dissociation produced abundant fragment ions convenient for structural analysis. In the daughter scan mode, ions were produced by cleavage of the glycosidic bonds, and not by cleavage at the sugar ring. These ions all contain ceramide moieties, except the sialic acid fragment ion. In the parent scan mode, product ions resulting from cleavage at the sugar ring were detected beside the ions resulting from cleavage at the glycosidic bonds, and ions of oligosaccharide fragments were also detected. In parent scan mode spectra of gangliosides based on the sialic acid ion, all ions contained a sialic acid residue, and the observed ions were similar to those obtained in the high-energy collision-activated dissociation daughter scan mode. These results indicate the usefulness of low-energy collision-activated dissociation tandem mass spectrometry in the daughter and parent scan modes for the analysis of ganglioside structure, in combination with fast atom bombardment mass spectrometry and high-energy collision-activated dissociation mass spectrometry.

Carbohydrate Conformation↗

Cholestasis induced by lithocholate and its glucuronide: their biliary excretion and metabolism.

We studied the effects of the infusion of lithocholate and lithocholate-3-sulfate and 3-glucuronide in rats (0.29 mumol/min per 100 g body weight for 40 min) on bile flow, together with their biliary excretion and metabolism. Lithocholate-glucuronide had a higher cholestatic effect than lithocholate, whereas lithocholate-sulfate had almost no effect on bile flow. Lithocholate was mainly converted to taurine or glucuronide conjugates in the bile, serum and liver and hydroxylation of the tauro-conjugate proceeded. Lithocholate-sulfate was almost completely excreted in the bile, mainly as tauro-conjugate. Lithocholate-glucuronide was excreted in bile almost without conjugation, while some taurine conjugation occurred in the serum and liver. These results suggest that the poor biotransformation of lithocholate-glucuronide is related to its higher cholestatic potency than lithocholate.

Alanine Transaminase↗