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Biomedical subjects

S Tsuchiya

Publications and source records attributed to S Tsuchiya.

At least 145 records · Page 8Linked to original sources
PubMed1996

Liposomal induction of a heat-stable macrophage priming factor to induce nitric oxide in response to LPS.

PURPOSE: The effects of liposomes on nitric oxide (NO) production from mouse peritoneal macrophages following intraperitoneal injection of liposomes were investigated. METHODS: Mouse peritoneal macrophages were collected following intraperitoneal injection of liposomes and cultured with and without lipopolysaccharide (LPS). Peritoneal washing fluid was also collected from the mice injected with liposomes. NO production was evaluated by measuring the concentration of nitrite in the macrophage culture supernatant by Griess reagent. RESULTS: NO production stimulated by LPS was observed in peritoneal macrophages obtained from the liposome-treated mice, but liposomes did not active macrophages directly to induce NO in response to LPS. NO production was higher in the liposomes composed of phosphatidylcholine than that of negatively charged liposomes composed of phosphatidylserine. Peritoneal washing fluid obtained from mice injected with liposomes has a capacity to induce NO production in the macrophages from naive mice. This capacity was not diminished by heat-treatment at 100 degrees C for 5 min. CONCLUSIONS: Peritoneal macrophages were activated to produce NO in response to LPS following intraperitoneal injection of liposomes. They did not activate macrophages directly, and the induction of heat-stable macrophage priming factor, but not cytokines, is suggested.

Animals↗
PubMed1996

alpha 2-macroglobulin stimulation of protein tyrosine phosphorylation in macrophages via the mannose receptor for Fc gamma receptor-mediated phagocytosis activation.

Macrophage phagocytic activity has previously been shown to be increased by binding of modified alpha 2-macroglobulin (alpha 2M) with mannose residues at termini of sugar chains to mannose receptors on macrophages, with a subsequent increase in the number of Fc gamma receptors at the cell surface. In the present study, an examination was made of the association of protein tyrosine kinase with the increase in number of Fc gamma receptors following binding of modified alpha 2M to mannose receptors. The phagocytosis of IgG-opsonized sheep red blood cells through the action of the Fc gamma receptor by modified alpha 2M was inhibited by mannose and herbimycin A and slightly so by genistein. The mannose receptor would thus appear to be associated with tyrosine kinase activity. By Western blotting, tyrosine phosphorylated proteins with molecular weights of 32000, 34000, 36000, 65000, 85000 and 110000 appeared or increased upon treating macrophages with modified alpha 2M. The degree of tyrosine phosphorylated proteins was the same for control macrophages following incubation in the presence of mannose and herbimycin A. Genistein treatment affected only tyrosine phosphorylated proteins of 65000 and 110000. The binding of modified alpha 2M to mannose receptors was demonstrated by the inducement of tyrosine kinase activation that was sensitive to herbimycin A, followed by an increase in Fc gamma receptors and consequently greater phagocytosis.

Animals↗
PubMed1996

Phase I study of a carboplatin-cisplatin-etoposide combination chemotherapy in advanced non-small-cell lung cancer.

Cisplatin (CDDP)-containing chemotherapy has become the mainstay of clinical trials in unresectable non-small-cell lung cancer (NSCLC), but the role of chemotherapy in the routine management of NSCLC remains controversial. We conducted a phase I study with the combination carboplatin (CBDCA), CDDP, and etoposide (Etop) in unresectable NSCLC. CBDCA, at a starting dose of 80 mg/m2, on day 1, was combined with a fixed dose of CDDP (80 mg/m2, day 1) and Etop (80 mg/m2, days 1-3). Escalation was performed after four patients entered at each dose level. If no World Health Organization (WHO) grade 4 toxicity developed after the first cycle in more than half of the patients or WHO grade 3/4 toxicity in more than two thirds, the dose was escalated. The maximum tolerated dose was established at 300 mg/m2 for CBDCA. Thrombocytopenia and leukopenia were the dose-limiting toxicities. No grade 3/4 nonhematologic toxicities were seen. The recommended dose of CBDCA to be combined with CDDP (80 mg/m2, day 1) and Etop (80 mg/m2, days 1-3) is 280 mg/m2. This trial suggests that our combination chemotherapy may be effective in patients with advanced NSCLC. A multicenter phase II study based on these findings is now under way.

Adult↗
PubMed1996

Mutations of the Epstein-Barr virus LMP-1 oncogene in a 10-year-old Japanese girl with nasopharyngeal carcinoma.

A 10-year-old patient with nasopharyngeal carcinoma (NPC) was studied for mutations within the carboxy-terminal portion of the Epstein-Barr virus (EBV) latent membrane protein (LMP)-1 gene. The EBV genome, defined as type A, was detected in biopsied tumor specimens by Southern hybridization with specific probes. Sequence analysis of the carboxy-terminal part of the LMP-1 gene revealed no deletions but seven single-base substitutions, four of which were found to be identical to those previously detected in codons for amino acids 322 to 366 in the Chinese NPC CAO. Although yet unresolved, the observed mutations may be associated with the pathogenesis of NPC.

Blotting, Southern↗
PubMed1996

Free radicals from 1-palmitoyl-2-arachidonoylphosphatidylcholine liposomes in Fe2+/ascorbic acid solution.

The generation of free radicals during the lipid peroxidation of liposomes composed of 1-palmitoyl-2-arachidonoylphosphatidylcholine (PAPC-liposome) in Fe2+/ascorbic acid (AsA) solution was studied by the ESR spin trapping technique. A carbon-centered radical adduct was observed using alpha-(4-pyridyl-1-oxide)-N-tert-butyl-nitorone (4-POBN) and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), but no oxygen-centered radicals such as .OH, LO., and LOO. were observed. The lipid peroxidation evaluated as 2-thiobarbituric acid reactive substances was inhibited by the addition of 4-POBN. The intensity of this inhibitory effect was dependent on the time when 4-POBN was added to the mixture of PAPC-liposomes and Fe2+/AsA solution, and no inhibitory effect could be observed after 4 min. The signal intensity of the carbon-centered radical adduct was dependent on the lipid concentration of PAPC-liposomes. These results suggest that the alkyl radicals generated from PAPC-liposome peroxidation induced by Fe2+/AsA were trapped by DMPO or 4-POBN at an earlier stage of lipid peroxidation.

Ascorbic Acid↗
PubMed1996

Isolation and characterization of two monoclonal antibodies that recognize different epitopes of the human c-kit receptor.

After immunizing mice with a human megakaryoblastic leukemia cell line, M-MOK, we obtained two monoclonal antibodies which recognize the human c-kit receptor. The monoclonal antibodies, designated MTK1 and MTK2, were found to specifically recognize Balb/3T3 cells transfected with human c-kit cDNA and not parent Balb/3T3 cells while showing different immunological, biochemical and biological behaviors. Both allowed visualization of the 140 kDa c-kit protein by Western blot analysis, but MTK1 detected only positive band with non-reducing conditions for sodium dodecyl sulfate-polyacrylamide gel electrophoresis. MTK1 partially inhibited the stem cell factor (SCF) induced proliferation of M-MOK cells, whereas, MTK2 was without effect. MTK1 also inhibited the bone marrow derived colony forming unit granulocyte/macrophage (CFU-GM) formed by granulocyte-macrophage colony stimulating factor (GM-CSF) and SCF. Not only anti-CD34 antibodies (HPCA-1) but also MTK1 could be shown to concentrate bone marrow CFU-GM and burst forming unit erythroid (BFU-E) effectively. The presently described monoclonal antibodies may therefore be useful for functional analysis of the ligand binding domain of the human c-kit receptor, as well as for further classification of hematopoietic stem cells in addition to the CD34 positive cells.

Animals↗
PubMed1996

IL-2 receptor gamma chain expression on CD34 positive hematopoietic progenitor cells from bone marrow and cord blood.

The IL-2 receptor (IL-2R) gamma chain is shared among receptors for IL-4, IL-7, IL-9 and IL-15 as well as IL-2. In order to clarify the functional role of these cytokines interacting with the common gamma chain in human early hematopoiesis, we studied expression of the IL-2R gamma chain on purified CD34 positive cells from bone marrow and cord blood. Broad populations of bone marrow mononuclear cells were all found to express the IL-2R gamma chain. CD34 positive cells were purified by CD34 monoclonal antibodies and immunomagnetic beads as representative hematopoietic progenitor cells. It was established that only 38 +/- 10% of CD34 positive bone marrow cells (n = 5) and 35 +/- 12% of CD34 positive cord blood cells (n = 11) expressed the IL-2R gamma chain. CD34(+) IL-2R gamma chain(+) and CD34(+) IL-2R gamma chain(-) cells fractionated by cell sorting were subjected to clonogenic assays that showed granulocyte-macrophage colony-forming cells (CFU-GM) were present evenly in both fractions, whereas erythroid burst-forming cells (BFU-E) were enriched in the CD34(+) IL-2R gamma chain(-) fraction approximately two- to six-fold as compared with CD34(+) IL-2R gamma chain(+) fraction. Such clonogenic features did not differ between the bone marrow and cord blood cases. These results indicate that CD34(+) IL-2R gamma chain(-) cells contain immature cells already committed to the erythroid lineage.

Adult↗
PubMed1996

Cell surface c-kit receptors in human leukemia cell lines and pediatric leukemia: selective preservation of c-kit expression on megakaryoblastic cell lines during adaptation to in vitro culture.

We produced a monoclonal antibody MTK1 which recognized c-kit protein. Using MTK1, 31 leukemia cell lines and 76 leukemia blasts from pediatric patients were analyzed for expression of the c-kit receptor by flow cytometry. The c-kit receptor was detectable on four of four cell lines assigned to the megakaryo/erythromegakaryoblastic lineage and on one of seven cell lines of myeloid lineage. C-kit expression was not seen on any of 20 cell lines of erythroid and lymphoid lineages. Furthermore, c-kit was expressed on 16 of 24 nonlymphoid blasts without platelet surface antigens (67%) and on six of eight non-lymphoid blasts with platelet surface antigens (75%), but was not detectable on 44 lymphoid blasts from pediatric leukemia patients. In these cases CD34 was expressed on 26 of 32 myeloid blasts (81%) and on 27 of 44 lymphoid blasts (61%). The findings indicate a dominant expression of the c-kit receptor on established cell lines assigned to the megakaryo/erythromegakaryoblastic lineage, though a high percentage of leukemic myeloblasts also expressed the c-kit receptor on their surface.

Antibodies, Monoclonal↗
PubMed1996

[Identification of mutations that were responsible for primary immunodeficiency diseases].

The genes responsible for many X-linked and autosomal recessive primary immunodeficiency diseases have been identified during the past two years. Now we can diagnose more than a dozen primary immunodeficiency diseases by genetic methods as well as immunological ones. We describe here two patients with leukocyte adhesion deficiency (LAD) and with X-linked agammaglobulinemia (XLA) the diagnoses of which were confirmed by genetic analysis. A patient with LAD showed a missense mutation of the CD18 gene from C to T at nucleotide position 605 resulting in a proline178-->leucine substitution. The mutation of the other allele has not yet been analyzed, because few CD18 mRNAs were translated from the mutated DNA. Another patient with XLA had a missense mutation of Btk gene at position 1204 of C to T resulting in a change of leucine358-->phenylalanine. In view of the mutation of the Sac I restriction site from GAGCTC to GAGTTC we can easily differentiate patients and the carrier from normal persons by the amplification of genomic Btk DNA. Through these studies unknown functions of these genes will be clarified in the near future.

Agammaglobulinemia↗
PubMed1996

Proliferation of macrophage-lineage cells in the bone marrow, severe thymic atrophy, and extramedullary hematopoiesis of possible donor origin in an autopsy case of post-transplantation graft-versus-host disease.

A case of proliferation of CD68-positive macrophage-lineage cells in the bone marrow accompanied by severe thymic atrophy associated with graft-versus-host disease (GVHD) in a boy given allogeneic bone marrow transplantation (BMT) is reported. A 7-year-old boy was treated for posthepatitic severe aplastic anemia by BMT from his HLA-identical, mixed lymphocyte reaction-negative sister. After the transplantation his peripheral blood group converted to the donor type. However, the patient suffered from acute and chronic GVHD and slowly progressive anemia, and he died of multiple organ failure 21 months after BMT. At the autopsy diffuse and monotonous proliferation of CD68-positive macrophage-lineage cells was found to be replacing the blood-forming cells in the bone marrow. The thymus was almost empty of T lymphocytes, and remaining strands of extremely atrophic epithelial cells showed focal cystic change. Extramedullary hematopoiesis was found in the spleen. Analyses of microsatellite markers suggested the hematopoietic cells in the spleen to be of donor origin.

Atrophy↗
PubMed1996

[Relationship between dietary life style in youth and osteoporosis].

The relationship between the dietary life style and osteoporosis was examined by comparing 71 osteoporotic women [age--65.5 +/- 8.9 (mean +/- SD)] with 76 women age-matched as controls. All subjects lived in and around Tsukuba City. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry. The frequencies of drinking milk and eating meat, fish, or potatoes, etc. both in their youth (about 18-25 years old) and at the present were investigated. The results were as follows: 1) The frequency of having unbalanced diets in their youth was significantly higher in osteoporotic patients than in controls. 2) During their youth, osteoporotic patients had significantly lower frequency of drinking milk, and significantly higher frequency of eating meat, dried fish or eggs, compared with controls. 3) High milk-consumers during their youth (milk-drinking: > or = 3 times per week) were significantly less frequent in osteoporotic patients than that in controls. 4) In the controls, the frequencies of drinking milk and eating meat during their youth were significantly positively correlated with lumbar BMD. The frequency of eating potatoes was significantly negatively correlated with the BMD in controls. 5) No strong relationships between present dietary life and osteoporosis or BMD were found. These findings suggest that drinking milk in their youth may influence BMD and associate with osteoporosis in women.

Adult↗
PubMed1996

[Rapid progression of adenocarcinoma of the lung in a patient with high levels of granulocyte colony-stimulating factor].

A 51-year-old man was referred and admitted to our hospital for further examination of an abnormal shadow on a chest X-ray film. One month before admission, a chest X-ray film had shown no abnormality. On admission, chest X-ray films and computed tomograms showed a tumor shadow in the right hilum, obstructive pneumonia in the right upper lobe, and a right-sided pleural effusion. Cytological examination of the pleural offusion revealed adenocarcinoma. The patients was given supportive care. The tumor grew rapidly and by the 13th hospital day it occupied whole right upper lobe. The patient died on the 21st day after admission. The white blood cell count had increased to 26540/mm3 as the adenocarcinoma grew. Serum granulocyte colony-stimulating factor (G-CSF), which increases the number of neutrophils in blood in vivo was examined. The serum G-CSF level reached 112 pg/ml. On immunohistochemical examination, the tumor cells stained positively with anti-G-CSF monoclonal antibody. The growth of this tumor was more rapid than expected for adenocarcinoma of the lung. These findings suggest that G-CSF induced growth of the tumor.

Adenocarcinoma↗
PubMed1995

Receptor-mediated transfer of pSV2CAT DNA to a human hepatoblastoma cell line HepG2 using asialofetuin-labeled cationic liposomes.

Asialofetuin-labeled liposomes (AF-lps) were developed as a vector for gene transfer to hepatocytes. Plasmid pSV2CAT DNA which encodes bacterial chloramphenicol acetyltransferase (CAT) was associated with (meaning, in this report, the sum of 'to be adsorbed on the surface of' and 'to be encapsulated into the internal phase of') AF-lps (AF-lps-pSV2CAT) prepared by a tandem combination of the detergent removal and freeze-thaw methods. Ninety-six percent of input pSV2CAT was associated with AF-lps containing N-(alpha-trimethylammonioacetyl)-didodecyl-D-glutamate chloride, and approx. two-thirds of the associated DNA was encapsulated into the internal phase. The uptake of AF-lps by the cultured human hepatoblastoma cell line HepG2, having asialoglycoprotein receptors (AGPR) on their plasma membrane, was decreased by the addition of free AF and cytochalasin B. AF-lps bound to HepG2 cells through specific interaction with AGPR, and were internalized into the cells by the receptor-mediated endocytotic pathway. HepG2 cells transfected by AF-lps-pSV2CAT showed a significantly higher CAT activity than those transfected by pSV2CAT associated with non-labeled control lps (N-lps-pSV2CAT) or a mixture of pSV2CAT and empty AF-lps. Pretreatment with EDTA-encapsulated AF-lps increased the transfection efficiency of AF-lps-pSV2CAT. The CAT activity in A431 and Swiss/3T3 cells transfected with AF-lps-pSV2CAT was low and almost the same as those transfected with N-lps-pSV2CAT. Since DNA encapsulated in lps is likely to be protected against digestion by nucleases in the blood circulation, AF-lps could be used as a gene transfer vector targeting the hepatocytes in vivo.

Asialoglycoprotein Receptor↗
PubMed1995

Identification of a highly specific surface marker of T-cell acute lymphoblastic leukemia and neuroblastoma as a new member of the transmembrane 4 superfamily.

Five monoclonal antibodies detected a surface antigen expressed exclusively on T-cell acute lymphoblastic leukemia (T-ALL) in a panel of 45 human hematopoietic cell lines, including T-cell lines derived from adult T-cell leukemia and those established by immortalization with human T-cell leukemia virus type 1 or Herpesvirus saimiri. Peripheral blood mononuclear cells, including fresh and activated T cells, were also completely devoid of this antigen. We designated this antigen as TALLA-1 (from T-ALL-associated antigen 1). By expression cloning, a cDNA clone encoding TALLA-1 was isolated from T-ALL cell line Molt-4. TALLA-1 was found to be a member of the transmembrane 4 superfamily (TM4SF). The cDNA was also essentially identical to A15, which was isolated from another T-ALL cell line, HPB-ALL, by differential hybridization with normal peripheral blood lymphocytes, and to CCG-B7, which was isolated from a brain cDNA library using CCG repeat as a probe. The gene product was now characterized in detail at the protein level. Northern blot analysis showed that the gene was expressed most strongly in brain, skeletal muscle and spleen. In a panel of 52 non-hematopoietic human cell lines, the majority of neuroblastoma cell lines were found to be positive for TALLA-1. Like ME491, CO-029 and L6, TALLA-1 may be another TM4SF member behaving as a potential tumor-associated antigen.

Amino Acid Sequence↗
PubMed1995

Contribution of mannose receptor to signal transduction in Fc gamma receptor-mediated phagocytosis of mouse peritoneal macrophages induced by liposomes.

The contribution of mannose receptors on the cell surface of mouse peritoneal macrophages to the process of liposome-induced phagocytosis of immunoglobulin G-opsonized sheep red blood cells (SRBCs) through Fc gamma receptor has been investigated. Fc gamma receptor-mediated phagocytosis of opsonized SRBCs was activated by modified alpha 2-macroglobulin, which was produced in the incubation mixture of alpha 2-macroglobulin and liposome-treated splenic B cells. The phagocytosis was specifically inhibited by the addition of D-mannose, and the inhibition was dependent on the D-mannose concentration. The binding of modified alpha 2-macroglobulin to macrophages was also reduced by the addition of D-mannose. The activation effect of modified alpha 2-macroglobulin was not inhibited when in the presence of alpha 2-macroglobulin-trypsin and -methylamine complexes. In the presence of cycloheximide, activated phagocytosis was reduced to the control level. By Scatchard plot analysis of IgG binding studies, the number of Fc gamma receptors of a macrophage had been increased to 4.6-fold that of a control macrophage by treatment with modified alpha 2-macroglobulin. These findings suggest that macrophage mannose receptors are involved in activating the process of Fc gamma receptor-mediated phagocytosis of opsonized SRBCs induced by modified alpha 2-macroglobulin. Lectins may participate in a signal transduction in macrophage activation by liposomes.

Animals↗
PubMed1995

Problems of neuroblastoma screening for 6 month olds and results of second screening for 18 month olds.

Nationwide neuroblastoma mass screening for 6-month-old infants (first screening) was introduced in Japan in 1985. About 110 neuroblastoma cases are detected annually by the first screening and treated, with a survival rate of 97%. Sensitivity of the first screening (positive cases/positive cases+false negative cases) is about 75%, and the prognosis of false-negative cases is unfavorable. A second screening at 18 months of age was started to rescue false-negative cases in Miyagi Prefecture in May 1992. Of 62 neuroblastoma cases treated in our hospital since 1985, 40 cases had received the first screening. Twenty cases were positive at first screening, 18 cases were false negative, and 2 cases were false negative and picked up by the second screening. Age distribution of false-negative cases ranged from 12 to 83 months and included 12 cases younger than 36 months old. Only 5 of 18 false-negative cases are alive without the disease. From May 1992 to November 1993, 14,282 infants had received the second screening (compliance rate: about 75%), and 2 neuroblastoma cases were detected. The first case was stage III with paraortic lymph node metastases, Shimada UH, aneuploidy and negative N-myc amplification. The second case was stage II with Shimada FH, aneuploidy, and negative N-myc amplification. Both cases are alive now without the disease after undergoing radical operation and chemotherapy. The first screening is effective for early detection of neuroblastoma cases, but the sensitivity is insufficient; the authors recommend a second screening to rescue false-negative cases.

Adrenal Gland Neoplasms↗
PubMed1995

A human CD4- CD8- T-cell receptor alpha beta + T leukemic cell line undergoing phytohemagglutinin-induced apoptosis.

A human CD4- CD8- alpha beta T-cell receptor (TCR alpha beta)+ T leukemic cell line, L-KAW, was established from the peripheral blood of a 6-year-old male patient with T-cell acute lymphoblastic leukemia. Its phenotype was found to be CD7+CD2+CD3+CD4-CD8- TCR alpha beta +. The cell line proved susceptible to killing by exposure to a mitogenic concentration of phytohemagglutinin (PHA) within several hours, with biochemical analyses demonstrating extensive degradation of DNA to oligonucleosomal bands characteristic of apoptosis. Chromatin condensation and cell shrinkage features of apoptotic cells could also be clearly identified under the electron microscope. The apoptosis-related Fas antigen was expressed on L-KAW cells and DNA fragmentation was induced by incubation with anti-Fas monoclonal antibody. The c-myc mRNA levels declined within 15 min to 3 h after the addition of PHA. These results suggest that L-KAW cells are specifically sensitive to induction of apoptosis in response to PHA without preactivation. They may, therefore, be considered an analog of activated T-cells and prove useful as a model system for characterizing biochemical and molecular mechanisms underlying the process of this type of cell death.

Antibodies↗