PubMed Health⌕ Search

Biomedical subjects

S Kusumoto

Publications and source records attributed to S Kusumoto.

At least 19 recordsLinked to original sources
PubMed2002

Prognostic significance of the null genotype of glutathione S-transferase-T1 in patients with acute myeloid leukemia: increased early death after chemotherapy.

We investigated the prognostic significance of genetic polymorphism in glutathione-S transferase mu 1 (GSTM1), glutathione-S transferase theta 1 (GSTT1), NAD(P)H:quinone oxidoreductase (NQO1) and myeloperoxidase (MPO), the products of which are associated with drug metabolism as well as with detoxication, in 193 patients with de novo acute myeloid leukemia (AML) other than M3. Of the patients, 64.2% were either homozygous or heterozygous for GSTT1 (GSTT1(+)), while 35.8% showed homozygous deletions of GSTT1 (GSTT1(-)). The GSTT1(-) group had a worse prognosis than the GSTT1(+) group (P = 0.04), whereas other genotypes did not affect the outcome. Multivariate analysis revealed that GSTT1(-) was an independent prognostic factor for overall survival (relative risk: 1.53; P = 0.026) but not for disease-free survival of 140 patients who achieved complete remission (CR). The rate of early death after the initiation of chemotherapy was higher in the GSTT1(-) group than the GSTT1(+) group (within 45 days after initial chemotherapy, P = 0.073; within 120 days, P = 0.028), whereas CR rates and relapse frequencies were similar. The null genotype of GSTT1 might be associated with increased toxicity after chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Multicenter prospective study of interferon-alpha versus bone marrow transplantation for newly diagnosed patients with chronic myelogenous leukemia: a preliminary analysis.

Interferon-alpha (IFN-alpha) therapy was compared with bone marrow transplantation (BMT) in patients with chronic myelogenous leukemia (CML) in a multicenter, prospective study. Of 254 evaluable patients, 175 received IFN-alpha and 79 received allogeneic BMT, 50 of whom received transplants from human leukocyte antigen (HLA)-identical related donors and 29 from HLA-matched unrelated donors. Complete hematologic response was achieved by 148 patients (89%) in the IFN-alpha group and 53 (78%) in the BMT group. In the IFN-alpha group, a complete cytogenetic response was induced in 25 patients (15%), a partial cytogenetic response in 37 (23%), and a minor cytogenetic response in 41 (25%). At a median follow-up of 38 months, in the IFN-alpha group the predicted 5-year survival rate was 79%, and the predicted 5-year rate of remaining in chronic phase was 66%. In the BMT group the predicted 5-year survival rate was 72% for related-donor BMT and 67% for unrelated-donor BMT. Among low Sokal-risk patients, 5-year survival did not differ between IFN-alpha therapy and BMT, irrespective of age. In higher Sokal-risk patients, survival for related-donor BMT and unrelated-donor BMT tended to be better than that with IFN-alpha therapy in younger patients. On the other hand, in older patients, survival in the BMT group, especially for those receiving unrelated-donor BMT, appeared to be inferior to that in the IFN-alpha group. Unrelated-donor BMT can be recommended for high-risk younger patients. However, for older patients, it should be performed after careful consideration of prognostic factors such as age, Sokal score, and response to IFN-alpha.

Adolescent↗
PubMed2001

Structural elucidation of a capsular polysaccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn's disease.

The structure of a capsular polysaccharide (CPS) from a clinical isolate of Bacteroides vulgatus was elucidated. B. vulgatus IMCJ 1204 was isolated from feces of a patient with Crohn's disease. CPS was prepared by phenol/water extraction of the bacterial cells followed by hydrophobic interaction chromatography and then gel filtration chromatography of the extract. The structure of CPS was determined by chemical analysis and NMR spectroscopy including DQF-COSY, TOCSY, ROESY, HSQC-TOCSY, HMQC and HMBC to be a polysaccharide composed of the following repeating unit: -->3)beta-D-Glcp(1-->6)[alpha-D-GalpNAc(1-->2)beta-D-Galp(1-->4)]beta-D-GlcpNAc(1-->3)alpha-D-Galp(1-->4)beta-D-Manp(1-->.

Bacterial Capsules↗
PubMed2001

Heparin modulates integrin function in human platelets.

PURPOSE: Heparin binds to human platelets and can cause activation and aggregation, although the mechanisms are unknown. To determine how heparin alters platelet function, we identified platelet-binding sites for heparin and measured heparin's influence on the function of platelet integrin alpha(IIb)beta(3) (glycoprotein IIb/IIIa). METHODS: Photoaffinity cross-linking and affinity chromatography experiments were performed to identify platelet membrane proteins that bind heparin. Heparin's effect on fibrinogen binding to platelets was measured with a radioligand-binding assay. The translocation to the cytoskeleton of Rap2, a guanosine triphosphate-binding protein, was measured from platelets aggregating in response to heparin and other agonists. RESULTS: Cross-linking and affinity chromatographic experiments positively identified the integrin alpha(IIb)beta(3) as a heparin-binding site. Heparin aggregation was calcium dependent. Low concentrations of unfractionated porcine mucosal heparin (2-5 U/mL) significantly increased fibrinogen I 125 binding to activated platelets, whereas higher doses did not. Heparin-mediated platelet aggregation was completely blocked by GRGDS peptide (5 mmol/L), a competitive inhibitor of fibrinogen binding, and was blocked by EDTA (2 mmol/L), which dissociates the functional integrin complex. Aggregation was associated with Rap2 translocation to the cytoskeleton, a sign of outside-in signaling. CONCLUSIONS: Heparin binds to the alpha(IIb)beta(3) integrin in vitro and ex vivo, and heparin increases fibrinogen binding to the integrin. Heparin-mediated aggregation requires an intact integrin and ligand and leads to Rap2 translocation to the cytoskeleton-an outside-in signal of ligand engagement. Heparin may directly modulate platelet integrin function, most likely through direct binding and modulation of integrin function.

Binding Sites↗
PubMed2001

Human MD-2 confers on mouse Toll-like receptor 4 species-specific lipopolysaccharide recognition.

Toll-like receptor 4 (TLR4) recognizes lipopolysaccharide (LPS). MD-2 is associated with TLR4 and imparts LPS responsiveness to it. Little is known, however, as to whether MD-2 directly regulates LPS recognition by TLR4. To address the issue, we took advantage of a species-specific pharmacology of lipid IVa, an analogue of lipid A. Lipid IVa acted agonistically on mouse (m) TLR4/MD-2 but not on human (h) TLR4/MD-2. Lipid IVa antagonized the agonistic effect of lipid A on hTLR4/MD-2. We examined the chimeric complex consisting of mTLR4 and hMD-2 to ask whether species specificity is conferred by TLR4 or MD-2. hMD-2 was clearly distinct from mMD-2 in the way of influencing LPS recognition by mTLR4. hMD-2 conferred on mTLR4 responsiveness to lipid A but not to lipid IVa. Moreover, lipid IVa acted as a lipid A antagonist on mTLR4 that is associated with hMD-2. Collectively, MD-2 directly influences the fine specificity of TLR4.

Adjuvants, Immunologic↗
PubMed2001

Chemical structure and biological activity of a lipid A component from Helicobacter pylori strain 206.

The chemical structure of a lipid A, which was obtained as a minor component from lipopolysaccharide of Helicobacter pylori strain 206-1, was determined to be a glucosamine beta-(1 -6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid, (R)-3- hydroxyhexadecanoic acid, and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2-, 3- and 2'-positions, respectively. Compared with the other major lipid A from the same strain, which was previously reported [Suda Y, Ogawa T, Kashihara W et al. Chemical structure of lipid A from Helicobacter pylori strain 206-1 lipopolysaccharide. J Biochem 1997; 121: 1129--1133], the structure was very similar with one exception. An (R)-3-hydroxyhexadecanoic acid was present at the 3-position of the novel lipid A component. The structure is apparently identical to one of the proposals by Moran et al. [Moran AP, Lindner B, Walsh EJ. Structural characterization of the lipid A component of Helicobacter pylori rough- and smooth-form lipopolysaccharides. J Bacteriol 1997; 179: 6453--6463], who concluded the same structure as the so-called major lipid A from the H. pylori strain NCTC 11637 but without isolating a homogeneous component. The endotoxic properties and pro-inflammatory cytokine-inducing activities of this novel tetra-acyl type lipid A were lower than those of previously reported major tri-acyl type lipid A.

Animals↗
PubMed2001

[CD7(+) acute myeloid leukemia (M0) associated with a mediastinal bulky mass lesion].

A 41-year-old man visited his doctor in May 2000 because of a sore throat and high fever. His symptoms did not improve, despite administration of antibiotics and nonsteroidal anti-inflammatory drugs. Since a chest X-ray examination revealed an anterior mediastinal bulky tumor, he was referred and admitted to our hospital on June 21, 2000. The peripheral white blood cell count was 44,540/microliter with 74% myeloblasts. Bone marrow aspiration revealed a hypercellular marrow with 82% myeloblasts, which were negative for peroxidase and alpha-naphthyl butylate esterase staining. Blast cells were positive for CD7, CD13, CD33, CD34, and HLA-DR, and negative for CD56. A needle biopsy specimen of the mediastinal tumor consisted of myeloblasts. We diagnosed the patient as having CD7 (+) acute myeloid leukemia (AML) (M0) with a bulky mediastinal mass based on the surface marker analysis, although the clinical features resembled myeloid/NK precursor acute leukemia. The patient achieved a complete remission after two courses of induction therapy. We are planning an allogeneic stem cell transplantation during his first remission because of the high risk of relapse.

Adult↗
PubMed2000

Cytokine-inducing macromolecular glycolipids from Enterococcus hirae: improved method for separation and analysis of its effects on cellular activation.

Previously, we showed that several minor macromolecular glycolipids accounting for less than 5% of the lipoteichoic acid (LTA) fraction from Enterococcus hirae ATCC 9790 possess cytokine-inducing activity, whereas the purified LTA does not. In other words, the immunobiological activity of the LTA fraction reported in the 1980s was not attributable to LTA itself, but to other glycolipids coexisting in the fraction. In the present study, we improved the procedure of separation of the active glycolipids and evaluated their effects on cellular activation. The immunobiologically active glycolipids were separated from the crude glycolipid fraction obtained by hot phenol-water extraction of the cells. The total yield of active glycolipids was about fivefold higher than that separated by the previous method. Interleukin-6-inducing activities of the active glycolipids from 1,25-dihydroxy vitamin D(3)-differentiated human monocytic leukemia cells, THP-1, were inhibited by anti-CD14 mAbs in a dose-dependent manner. Macrophages from Toll-like receptor (TLR)-2-deficient or -4-deficient mice completely lacked the ability to produce tumor necrosis factor-alpha on stimulation with active glycolipids. These observations indicated that the cellular activation by the active glycolipids from E. hirae is mediated by CD14 and by both TLR2 and TLR4.

Animals↗
PubMed2000

Prognostic value of p53 gene mutations and the product expression in de novo acute myeloid leukemia.

In acute myeloid leukemia (AML), p53 mutations are reportedly infrequent but associated with a poor prognosis. The majority of mutations are missense mutations, which generally lead to accumulation of nuclear p53 protein. However, the prognostic significance of the accumulation remains unknown in AML. In this study, we compared the prognostic value of p53 mutations versus accumulation of the product. p53 mutations were found in 9 (4.5%) of 200 patients with de novo AML. The p53 mutation detectable (mutation+) group had a worse prognosis (p = 0.0009) than the mutation not detectable (mutation-) group. Multivariate analysis showed that the p53 mutation was an independent factor (p = 0.005) for short overall survival as well as 60 yr or older (p = 0.001) and unfavorable karyotypes (p = 0.001). In 79 of the 200 patients, the expression of p53 was studied by immunocytochemistry (ICC) using anti-p53 monoclonal antibody (DO-7). All samples carrying missense mutations (N = 6) were positive for ICC in over 15% of nuclei of each sample, chosen as the optimized cutoff value of p53 accumulation. Accumulation was thus found in 14 of the 79 patients. However, there was no prognostic difference according to the accumulation, because the mutation-/accumulation+ group (N = 8) tended to have a good prognosis. These findings indicate that molecular detection of p53 mutations yields better prognostic information than ICC. In a subset of AML, p53 protein might be accumulated without mutation presumably due to upstream signals of p53.

Acute Disease↗
PubMed2000

Intrinsic conformation of lipid A is responsible for agonistic and antagonistic activity.

Lipopolysaccharides (LPS, endotoxin) represent a major virulence factor of Gram-negative bacteria, which can cause septic shock in mammals, including man. The lipid anchor of LPS to the bacterial outer membrane, lipid A, exhibits a peculiar chemical structure, harbours the 'endotoxic principle' of LPS and is also responsible for the expression of pathophysiological effects. Chemically modified lipid A can be endotoxically inactive, but may express strong antagonistic activity against endotoxically active LPS. By applying orientation measurements with attenuated total reflectance (ATR) infrared spectroscopy on hydrated lipid A samples, we show here that these different biological activities are directly correlated to the intrinsic conformation of lipid A. Bisphosphoryl-hexaacyl lipid A molecules with an asymmetric (4/2) distribution of the acyl chains linked to the diglucosamine backbone have a large tilt angle (> 45 degrees ) of the diglucosamine backbone with respect to the membrane surface, a conical molecular shape (larger cross-section of the hydrophobic than the hydrophilic moiety), and are endotoxically highly active. Monophosphoryl hexaacyl lipid A has a smaller tilt angle, and the conical shape is less expressed in favour of a more cylindrical shape. This correlates with decreasing endotoxic activity. Penta- and tetraacyl lipid A or hexaacyl lipid A with a symmetric acyl chain distribution (3/3) have a small tilt angle (< 25 degrees ) and a cylindrical shape and are endotoxically inactive, but may be antagonistic.

Carbohydrate Conformation↗
PubMed2000

Toll-like receptor 4 imparts ligand-specific recognition of bacterial lipopolysaccharide.

Lipopolysaccharide (LPS) is the main inducer of shock and death in Gram-negative sepsis. Recent evidence suggests that LPS-induced signal transduction begins with CD14-mediated activation of 1 or more Toll-like receptors (TLRs). The lipid A analogues lipid IVa and Rhodobacter sphaeroides lipid A (RSLA) exhibit an uncommon species-specific pharmacology. Both compounds inhibit the effects of LPS in human cells but display LPS-mimetic activity in hamster cells. We transfected human TLR4 or human TLR2 into hamster fibroblasts to determine if either of these LPS signal transducers is responsible for the species-specific pharmacology. RSLA and lipid IVa strongly induced NF-kappaB activity and IL-6 release in Chinese hamster ovary fibroblasts expressing CD14 (CHO/CD14), but these compounds antagonized LPS antagonists in CHO/CD14 fibroblasts that overexpressed human TLR4. No such antagonism occurred in cells overexpressing human TLR2. We cloned TLR4 from hamster macrophages and found that human THP-1 cells expressing the hamster TLR4 responded to lipid IVa as an LPS mimetic, as if they were hamster in origin. Hence, cells heterologously overexpressing TLR4 from different species acquired a pharmacological phenotype with respect to recognition of lipid A substructures that corresponded to the species from which the TLR4 transgene originated. These data suggest that TLR4 is the central lipid A-recognition protein in the LPS receptor complex.

Animals↗
PubMed1999

Synthesis of heparin partial structures and their binding activities to platelets.

A synthetic pentasaccharide corresponding to the antithrombin III-binding region in heparin was also found to bind to human platelets. To identify the platelet-binding site in the pentasaccharide which is expected to be a novel sequence in heparin responsible for its platelet-binding, five partial structures of this particular pentasaccharide were synthesized. In a competitive assay using [3H]-heparin, a trisaccharide, O-(2-deoxy-2-sulfamido-3,6-di-O-sulfo-alpha-D-glucopyranosyl)-1--> 4)-O-(2-O-sulfo-alpha-L-idopyranosyluronic acid)-(1-->4)-2-deoxy-2-sulfamido-6-O-sulfo-alpha-D-glucopyranose, was concluded to be a high-affinity site for heparin's binding to platelets.

Antithrombin III↗
PubMed1999

S-form lipopolysaccharide (LPS), but not lipid A or R-chemo-type LPS, induces interleukin-6 production in vitamin D3-differentiated THP-1 cells.

Bacterial lipopolysaccharide (LPS) induces the production of various inflammatory cytokines and the inducibility is considered attributable to the glycolipid part of LPS called lipid A. We report an in vitro model in which lipid A is not necessarily a minimal structure for the LPS activity. Vitamin D3-differentiated THP-1 cells, cultured human monocytic leukemia cells, produced a high level of interleukin-6 (IL-6) by stimulating LPS from Escherichia coli O111:B4, but not by stimulating synthetic E. coli-type lipid A (compound 506), E. coli Re mutant LPS (ReLPS), or alkali-treated LPS. The induction by LPS was inhibited by the anti-CD14 antibodies or by the synthetic lipid A precursor (compound 406). An alkali-treated LPS or compound 506 partially inhibited the LPS-induced IL-6 production. These facts suggest that lipid A alone is not sufficient for the IL-6-inducing activity, but the polysaccharide part in LPS contributes or acts as a co-factor for activation of differentiated THP-1 cells.

Alkalies↗
PubMed1999

Fusion of TEL/ETV6 to a novel ACS2 in myelodysplastic syndrome and acute myelogenous leukemia with t(5;12)(q31;p13).

We identified a novel human long fatty acyl CoA synthetase 2 gene, ACS2, as a new ETV6 fusion partner gene in a recurrent t(5;12)(q31;p13) translocation in a patient with refractory anemia with excess blasts (RAEB) with basophilia, a patient with acute myelogenous leukemia (AML) with eosinophilia, and a patient with acute eosinophilic leukemia (AEL). ACS2 is expressed in the brain and bone marrow and is highly conserved in man and rats. The resulting ETV6/ACS2 fusion transcripts showed an out-frame fusion of exon 1 of ETV6 to exon 1 of ACS2 in the AEL case, an out-frame fusion of exon 1 of ETV6 to exon 11 of ACS2 in the AML case, and a short in-frame fusion of ETV6 exon 1 to the 3' untranslated region of ACS2 in the RAEB case. Reciprocal ACS2/ETV6 transcripts were identified in two of the cases. Fluorescence in situ hybridization (FISH) analysis with ETV6 cosmids on 12p13, and BACs and P1s on 5q31, demonstrated that the 5q31 breakpoints of the AML and AEL cases involved the 5' portion of the ACS2 gene, and that the 5q31, breakpoint of the RAEB case involved the 3' portion of the ACS2 gene. None of the resulting chimeric transcripts except for the ACS2/ETV6 transcript in the RAEB case led to a fusion protein. Disruption of the second ETV6 allele by t(12;19) was detected in the AML case by FISH analysis. These observations suggest that the disruption of ETV6 and/or ACS2 may lead to the pathogenesis of hematologic malignancies with t(5;12)(q31;p13).

Adult↗
PubMed1999

Positive selection of NKT cells by CD1(+), CD11c(+) non-lymphoid cells residing in the extrathymic organs.

Previously, we found that NK1.1(+), TCRalpha beta(+) natural killer T (NKT) cells develop in cytokine-supplemented suspension cultures of fetal liver established from normal, but not from beta2 microglobulin-deficient [beta2m(- / -)] mice, and that recombination-deficient SCID fetal liver can reconstiute NKT cell development in beta2m(- / -) fetal liver cultures. We found here that cells of SCID adult liver, bone marrow, spleen and thymus were able to reconstitute NKT cell development in the former culture system with efficiency comparable to normal thymic cells. The reconstitution of NKT cells was also seen in the bone marrow chimeras that had been administered a combination of beta2m(- / -) and Rag-2(- / -) bone marrow cells. Development of NKT cells was hampered by depletion of CD11c(+) or CD11b(+) cells, but not by removal of B220(+) or Gr-1(+) cells from cultures of normal fetal liver cells. Furthermore CD11c(+), CD11b(+) and / or CD11c(+) CD11b(-) cells (both populations were CD1-dull positive) enriched from Rag-2-deficient fetal livers and pulsed with alpha-galactosylceramide, a possible antigen for NKT cells, were shown to reconstitute the NKT cell development in beta2m(- / -) fetal liver cultures. Collectively, our findings suggest that non-lymphoid cells, presumably CD11c(+), CD11b(+) and / or CD11c(+), CD11b(-) dendritic cells, are involved in the mechanism of positive selection of NKT cells in the thymus and extrathymic organs.

Animals↗
PubMed1999

A novel cytokine-inducing glycolipid isolated from the lipoteichoic acid fraction of Enterococcus hirae ATCC 9790: a fundamental structure of the hydrophilic part.

Previously, we showed that quantitatively minor several glycolipids totaling only less than 5% of the lipoteichoic acid (LTA) fraction from Enterococcus hirae ATCC 9790 possessed cytokine-inducing activity, whereas the major component (over 90%) did not [Suda et al. (1995) FEMS Immun Med Microbiol 12:97-112]. The major inactive component was shown to have the chemical structure as was proposed for the LTA by Fischer [Hashimoto et al. (1997) J Biochem 121:779-86], suggesting that so-called LTA is not a cytokine-inducing component in the Gram-positive bacteria. In the present paper, the structure of the hydrophilic part of one of the cytokine-inducing glycolipid tentatively named GL4 is elucidated. GL4 was first subjected to hydrolysis with aqueous HF to give a polysaccharide and a mixture of low molecular weight products. The polysaccharide was composed mainly of highly branching mannan as concluded from NMR and MS analyses of its acetolysis products. The low molecular weight products consisted of phosphate and glycerol, suggesting the presence of a poly(glycerophosphate) structure in the original GL4. From these observations, the hydrophilic part of GL4 was shown to consist of mannose-rich polysaccharide and poly(glycerophosphate), the latter being bound to the former by a phosphodiester linkage.

Carbohydrate Sequence↗
PubMed1999

New system for assessing the prognosis of refractory anemia patients.

Refractory anemia (RA) is a very heterogeneous disease regarding biological and clinical features. The International Prognostic Scoring System (IPSS) was useful for assessing the prognosis in the whole group of 219 myelodysplastic syndrome (MDS) patients. However, the IPSS was not sufficient in 132 RA patients. To predict survival and freedom from acute myeloid leukemia (AML) evolution, we investigated individual prognostic factors based on the clinical parameters (age, gender, morphologic features, cytopenias and cytogenetics) of 132 RA patients using univariate and multivariate analyses. Based on the results, we devised a new system for assessing the prognosis of RA patients. In our system, RA patients with pseudo-Pelger-Huët anomalies >/=3% were classified as high risk (12 patients); of patients without pseudo-Pelger-Huët anomalies >/=3%, those with intermediate/poor karyotype according to IPSS, Hb </=6 g/dl or mMgk >/=10% were classified as intermediate risk (57 patients); and those without high or intermediate risk were classified as low risk (67 patients). In our system, the analyses of both survival times and leukemia-free survival times revealed significant differences among the three groups (P < 0.0001).

Acute Disease↗