Biomedical subjects

S Negoro

Publications and source records attributed to S Negoro.

At least 127 records · Page 7Linked to original sources

PubMed1989

Mutant fibronectin gene in skin fibroblasts of sclerotic lesions from patients with progressive systemic sclerosis.

A mutant fibronectin gene was identified in skin fibroblasts obtained from sclerotic lesions of 7 patients with progressive systemic sclerosis. We found 2 point mutations adjacent to the cell-attachment tetrapeptide DNA sequence in the cell-binding domain of the fibronectin gene. This observation suggests that the mutant fibronectin is related to an integral component of sclerotic pathogenesis through abnormal cellular interactions.

Amino Acid Sequence↗

PubMed1989

Decreased expression of interleukin-2 binding molecules (p70/75) in T cells from patients with systemic lupus erythematosus.

Using radiolabeled interleukin-2 (IL-2), affinity cross-linking and binding assays revealed that the expression of intermediate-affinity IL-2 binding molecules (p70/75) on freshly prepared T cells from patients with systemic lupus erythematosus (SLE) was significantly decreased in comparison with that in normal subjects. The proliferative response of T cells to high doses of IL-2 was also reduced in patients with SLE. The decreased expression of p70/75 reflects the hyporesponsiveness to IL-2 of T cells in patients with SLE.

Adult↗

PubMed1989

Administration of recombinant IL-2 augments the level of serum IgM in an IL-2 deficient patient.

A patient with ataxia telangiectasia was treated with recombinant interleukin-2 (rIL-2) and the resulting immunological effects evaluated. The patient lacked IL-2 production, and immunoglobulin synthesis was also impaired. Treatment with IL-2 selectively increased serum IgM without any significant side effects. Therapy also restored B-cell function in vitro. IgM production as well as the proliferative response to Staphylococcus aureus strain Cowan I. These results suggest that IL-2 treatment may correct both T-cell and B-cell defects.

Adolescent↗

PubMed1989

Demonstration of functional immaturity of signal transduction pathways in human cord T cells.

We examined the nature of cytoplasmic signal transduction pathways in cord blood T cells by stimulating them with tumor promoter (TPA) and calcium ionophore (A23187). Costimulation of T cells with TPA and A23187 induced optimal proliferative responses on Day 2 in cord T cells but on Day 4 in adult T cells. The maximal responses observed in cord T cells were much less than those of adult T cells, whereas the Con A-induced proliferative responses of these cells showed no significant differences. The reduced responses of cord T cells were due to their lower efficiency in activating the cellular events in T cell activation and proliferation phase, because cord T cells have significantly less ability than adult T cells to express IL-2 receptor as well as HLA-DR and produce IL-2 molecules, thereby inducing proliferation. These data show immature characteristics of intracellular signal transduction pathways in cord T cells, which are directly related with the functional immaturity of cord T cells.

Adult↗

PubMed1989

Immunopharmacological actions of an extract isolated from inflamed skin of rabbits inoculated with Vaccinia virus (Neurotropin)--II. Restorative effect on immune responses through the recovery of IL-2 production in aging mice.

To examine the immunopharmacological actions of an extract isolated from inflamed skin of rabbits inoculated with Vaccinia virus (Neurotropin), its effect on the immune responses in aging BALB/c mice was examined. Neurotropin clearly restored the decreasing T-cell-dependent immune responses such as delayed-type hypersensitivity (DTH) response and plaque-forming cells (PFC) response to sheep red blood cells (SRBC) when administered i.p. from 13 months old (mo) to 16 mo. However, Neurotropin administration from 2 to 5 mo had no effect on the immune responses of young animals. Neurotropin administration from 13 to 16 mo restored not only the T-cell proliferation of spleen cells induced by concanavalin A (Con A) and phytohemagglutinin (PHA), but also the interleukin-2 (IL-2) production by spleen cells activated with Con A. However, Neurotropin did not affect the responsiveness of Con A-activated spleen cells to exogenous recombinant IL-2. An absence of suppressor cells capable of inhibiting the IL-2 production in the spleens was confirmed in the 16 mo mice. Neurotropin administration also restored IL-1 production by peritoneal macrophages stimulated with lipopolysaccharide (LPS). These results suggest that long-term administration of Neurotropin restores the decreasing T-cell-dependent immune responses through the recovery of IL-2 and in part IL-1 production, but not the responsiveness to IL-2 in aging BALB/c mice.

Adjuvants, Immunologic↗

PubMed1989

Three-year disease-free survivors of small cell lung cancer treated with combination chemotherapy with or without chest irradiation.

One hundred and seventy-four patients with small cell lung cancer (SCLC) treated with combination chemotherapy, with or without chest radiation, were analyzed. Fourteen patients (8%) survived for 3 years or more. Three-year disease-free survival continued for 12 of the 101 patients (12%) with limited disease, and one of 75 (1%) with extensive disease (P less than 0.05). Patients' sex and performance status were not important in achieving long-term survival. All disease-free survivors, except two who could not be evaluated, achieved a complete response. Although the treatment programs had some influence on the long-term survival rates (P less than 0.05), thoracic radiation did not have significant impact on long-term survival. Three of the 13 patients (23%) developed second malignancies and died, and one of these patients also suffered from a progressive neurologic deterioration with dementia. Two other patients died free of SCLC. Consequently, eight have remained alive and free of disease. The last relapse was observed at 1.5 years from beginning of treatment. The disease-free survival may offer the hope of cure of SCLC. However, the survivors are at an increased risk of developing late complications including second malignancies and neurologic abnormalities. Therefore, careful follow-up will be necessary.

Adult↗

PubMed1989

Plasmid dependence of Pseudomonas sp. strain NK87 enzymes that degrade 6-aminohexanoate-cyclic dimer.

A bacterial strain, Pseudomonas sp. strain NK87, that can use 6-aminohexanoate-cyclic dimer as the sole source of carbon and nitrogen was newly isolated from wastewater of a factory which produces nylon-6. Two responsible enzymes, 6-aminohexanoate-cyclic-dimer hydrolase (P-EI) and 6-aminohexanoate-dimer hydrolase (P-EII), were found in the NK87 strain, as is the case with Flavobacterium sp. strain KI72, another 6-aminohexanoate-cyclic-dimer-metabolizing bacterium (H. Okada, S. Negoro, H. Kimura, and S. Nakamura, Nature [London] 306:203-206, 1983). The P-EI enzyme is immunologically identical to the 6-aminohexanoate-cyclic-dimer hydrolase of KI72 (F-EI). However, antiserum against the 6-aminohexanoate-dimer hydrolase purified from KI72 (F-EII) did not react with cell extracts of NK87, indicating that the F-EII and P-EII enzymes are immunologically different. Restriction endonuclease analyses show that the NK87 strain harbors at least six plasmids ranging in size from 20 to 80 kilobase pairs (kbp). The P-EI and P-EII genes were cloned in Escherichia coli. Both the P-EI and F-EI probes strongly hybridized with a 23-kbp plasmid in Southern hybridization analyses. The P-EII probe hybridized specifically with an 80-kbp plasmid, but the F-EII probe hybridized with none of the plasmids harbored in NK87. These results indicate that the P-EI gene and P-EII gene are encoded on the 23-kbp and 80-kbp plasmids, respectively.

Amidohydrolases↗

PubMed1989

High homology between 6-aminohexanoate-cyclic-dimer hydrolases of Flavobacterium and Pseudomonas strains.

The nucleotide sequences of the genes for 6-aminohexanoate-cyclic-dimer hydrolases of Flavobacterium sp. strain K172 (F-nylA) and Pseudomonas sp. NK87 (P-nylA), enzymes essential for the degradation of a by-product of the nylon-6 industry, were obtained by the dideoxynucleotide chain-termination method. A 1,479-base-pair open reading frame starting at a GTG and terminating at a TGA was found for the both of the genes. The P-nylA and F-nylA genes encoded polypeptides of 493 amino acids and had only 10 base substitutions in the coding region, which caused seven amino acid substitutions.

Amidohydrolases↗

PubMed1989

Cloning, nucleotide sequence, and expression in Escherichia coli of the Bacillus stearothermophilus peroxidase gene (perA).

The gene encoding a thermostable peroxidase was cloned from the chromosomal DNA of Bacillus stearothermophilus IAM11001 in Escherichia coli. The nucleotide sequence of the 3.1-kilobase EcoRI fragment containing the peroxidase gene (perA) and its flanking region was determined. A 2,193-base-pair open reading frame encoding a peroxidase of 731 amino acid residues (Mr, 82,963) was observed. A Shine-Dalgarno sequence was found 9 base pairs upstream from the translational starting site. The deduced amino acid sequence coincides with those of the amino terminus and four peptides derived from the purified peroxidase of B. stearothermophilus IAM11001. E. coli harboring a recombinant plasmid containing perA produced a large amount of thermostable peroxidase which comigrated on polyacrylamide gel electrophoresis with the B. stearothermophilus peroxidase. The peroxidase of B. stearothermophilus showed 48% homology in the amino acid sequence to the catalase-peroxidase of E. coli.

Amino Acid Sequence↗

PubMed1989

Nuclear phosphotyrosyl-protein with DNA-binding ability in peripheral blood mononuclear cells from systemic lupus erythematosus patients.

This study examined the phosphorylation of cytoplasmic and nuclear proteins in peripheral blood mononuclear cells (PBMC) of systemic lupus erythematosus (SLE) patients. The cytoplasmic and nuclear protein kinase activity in PBMC from SLE patients was at least five-fold higher than that of normal healthy subjects. PBMC of SLE patients produced different nuclear endogenous substrates on phosphorylation and also displayed distinct protein kinase activity. Nuclear phosphoproteins, with human PBMC DNA-binding ability, of 38 kD and 70 kD were detected from both SLE patients and normal healthy subjects, while the 40 kD phosphoprotein, with tyrosine as the main phosphorylation residue, was found only in SLE patients. Other nuclear phosphoproteins, and most of the detected cytoplasmic phosphoproteins, were present in higher levels in both normal PBMC with mitogen stimulation, such as PHA, and SLE PBMC. The expression level of the 40 kD nuclear phosphotyrosyl-protein showed a positive correlation with the clinical disease activity of SLE. These results suggest that PBMC from SLE patients had distinct tyrosine protein kinase (TPK) activity and/or a different endogenous substrate of nuclear DNA-binding proteins in tyrosine phosphorylation. The possible significance of tyrosine phosphorylation in PBMC of SLE patients in the pathogenesis, and its clinical meaning, are discussed.

DNA↗

PubMed1989

Restorative effect of muroctasin on leukopenia caused by anticancer chemotherapy in lung cancer. Comparative study by envelope method.

N2-[(N-Acetylmuramoyl)-L-alanyl-D-isoglutaminyl]-N6-stearoyl-L-lysine (MDP-Lys(L18), muroctasin), a derivative of muramyl dipeptide, is known to have the activity to augment the number of white blood cells (WBC) via colony-stimulating factor. Muroctasin has been expected to be applied to leukopenia caused by anticancer chemotherapy. When WBC decreased to less than or equal to 3,000/mm3 after the 1st course of chemotherapy, 131 patients with lung cancer, who were previously classified by the combination regimens of chemotherapy, were enrolled in the study and randomized into 3 groups, 200 micrograms (H), 100 micrograms (L) and untreated control (C) groups. The patients were then subcutaneously treated once daily for 6 consecutive days. WBC and its differential count were measured on Days 4, 7 and 15 after commencement of the study. WBCs in H and L groups were recovered greater than in C group. In WBC differential count, the recovery of neutrophil was prominent in muroctasin treated groups. The portion of immature neutrophil in the bone marrow was also increased by muroctasin treatment. A restorative effect on WBC and neutrophil counts was also confirmed only in the second course of H group. On the other hand, fever and pain in the injected site as side effects were common in the H group and L group in both of courses. In this study, the usefulness of muroctasin in leukopenia was suggested when administered at dosages of 200 micrograms for 6 days.

Acetylmuramyl-Alanyl-Isoglutamine↗

PubMed1989

Changes in inducible nuclear factors with specific binding ability to c-myc gene fragments in peripheral blood mononuclear cells from systemic lupus erythematosus patients.

Using a gel retardation assay, we found new nuclear proteins of peripheral blood mononuclear cells (PBMC) from systemic lupus erythematosus (SLE) patients specifically binding to c-myc gene fragments. A different pattern could be detected between SLE patients and healthy controls for the c-myc exon I fragment, but both groups had similar patterns for the c-myc 5'-upper region fragment. For the c-myc exon I fragment, one DNA-protein complex was induced only in SLE patients and the other DNA-protein complex was amplified in SLE and normal PBMC with mitogen stimulation. It is suggested that abnormal c-myc protooncogene transcription in PBMC from SLE patients could be related to differences in nuclear specific binding proteins. These differences apparently play a key role in abnormal lymphocyte function in changes in gene regulation.

DNA↗

PubMed1989

C-myc gene binding factors in peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE).

We characterized the nuclear proteins with specific binding ability against c-myc gene by gel-shift assay in cell extracts of peripheral blood mononuclear cells (PBMC) from SLE patients and SLE-prone mice with use of distinct c-myc fragments. With the fragment named Fmyc in our experiments, two kinds of complexes which we call C1 and C2 respectively were found in PBMC from SLE patients and SLE-prone mice. The C1 was shown to be inducible in PBMC from healthy persons without nascent protein synthesis after lectin binding to the cell and found to be elevated in the SLE patients and in all of the established cell lines we examined. The C2 seemed to be peculiar to SLE subjects. The binding site of the C1 factor (C1F) and C2 factor (C2F) which forms C1 and C2 respectively with Fmyc appeared to be common and were found to reside at 51 kbp sequence (from XhoI to Sau3A) of exon I of c-myc gene. Interestingly, XhoI site of the binding site was highly demethylated in PBMC of SLE patients as compared with healthy persons. The roles of these binding factors for the pathogenesis of SLE are discussed.

DNA-Binding Proteins↗

PubMed1989

[The characteristic changes of immune function with aging].

It is well-known that the most prominent age-related immunological abnormalities were reduced immune response against foreign antigens and increased auto-antibody production against intrinsic antigens. To explain these immunological abnormalities, we examined the various functions of human lymphocytes from aged and young groups at cellular, molecular and genetic levels. The results indicate: The first, T cells from the aged showed significantly reduced proliferative response not only to specific antigen TAP but also to mitogen PHA or combined stimulation of PMA and ionomycin. The second, the number of IL-2 receptor, particularly high affinity ones, on aged T cells were significantly reduced in the aged after TAP and PHA stimulation. The third, the ability to express Tac (p55) and p70/75 of IL-2R and to internalize the rIL-2 bound to the receptor were reduced in aged T cells. The fourth, although the ability to proliferate in response to SAC stimulation was two folds less in the aged B cells than that in the young ones, the capacity to differentiate into IgG and IgA class ISC after the combined stimulation with SAC and partially purified BCDF were rather increased on the basis of the number of viable cells recovered. The fifth, the amount of IL-2 activity produced by aged T cells was ten fold less than that by young ones, but the amount of BCDF activity produced by aged T cells was three folds higher than that by young ones after PHA stimulation. An inverse correlation between IL-2 activity and BCDF activity was found when the both activities were determined in the same sample. The sixth, the combined stimulation with PMA and ionomycin could induce proliferative response to highly purified T cells, T cell subsets and B cells. The degree of age-related decline of the proliferative response of CD-8 positive T cells was most significant, that of CD-4 positive ones was next and that of B cells was least. The seventh, although the maximum of c-myc mRNA level was attained at 2 hr after the stimulation and similar amount between the both age groups, the amount of mRNA at 8 or 24 hr was rather higher in the aged T cells than in the young ones. The reduction of the degradation rate of c-myc mRNA seemed to be the cause. We found no difference of the maximum amount and kinetics of c-myb mRNA between both age groups in T cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1988

Age-related changes of heat shock protein gene transcription in human peripheral blood mononuclear cells.

In this study, we show the age-related retardation of heat shock 70 kD protein (hsp 70) gene transcription in peripheral blood mononuclear cells (PBMC). The amount of maximum transcription of the hsp 70 gene is decreased in PBMC from aged subjects, compared with PBMC from young control subjects. It might mean that the ability for homeostasis against heat shock stress decreases in PBMC from aged subjects. Our observation might be at least correlative and consistent with the age-related change of a possible essential function in PBMC.

Actins↗

PubMed1988

Age-related changes of expression of IL-2 receptor subunits and kinetics of IL-2 internalization in T cells after mitogenic stimulation.

The age-associated changes of the expression of IL-2 binding molecules p55/Tac(alpha chain) and p70/75(beta chain) were examined after phytohemagglutinin (PHA) stimulation. The expressions of both p55/Tac molecules and p70/75 molecules were significantly reduced in the aged compared with those in the young persons. The amounts of p55/Tac and p70/75 molecules on T cells from the aged were 55% and 59% of those on young ones, respectively. The ratio of the amount of p70/75 to that of p55/Tac in aged T cells was 0.28 and that in young ones was 0.26. The ratio was somewhat higher in the aged but not significantly. We also examined the kinetics of IL-2 internalization mediated by its receptor. The calculated t1/2 of receptor-mediated IL-2 internalization was 17 min in the aged and 16 min in the young, respectively. There was no kinetic difference between the 2 groups. The percentage of the internalized IL-2 to the sum total was 58.2% in the aged and 73.4% in the young (P less than 0.02). the amount of internalized IL-2 in T cells from the aged was 48.6% of that from the young (P less than 0.01).

Adult↗

PubMed1988

Lupus-related transcript homologous to Abelson-murine leukemia virus.

In the present study, we found the expression of transcripts homologous to Abelson murine leukemia virus (A-MuLV) in lupus-prone mice and nonautoimmune mice. One of them, as the lupus-related transcript, is expressed in only lupus-prone mice and induced by bacterial lipopolysaccharide (LSP). We could not induce the transcript by LSP in nonautoimmune mice that we examined. The significance of the transcript autoimmune events in lupus-prone mice is discussed.

Abelson murine leukemia virus↗

PubMed1988

5-Azacytidine induced inhibition of mitogenic response by agents that activate or augment activation of human peripheral blood T lymphocytes.

Previous work from our laboratory demonstrated the mitogenic response of human peripheral blood T lymphocytes by phytohemagglutinin (PHA), phorbol myristate acetate (PMA) and ionomycin, or interleukin 2 (IL-2). Increasing levels of incorporated 5-azacytosine inhibited the action of the methyltransferase suggesting that incorporation of 5-azacytosine into DNA could be responsible for the inhibiting effect of 5-azacytidine (5-aza-CR) on DNA methylation. In this study, we first demonstrated the inhibition of mitogenic response by agents, such as PHA, PMA and ionomycin, or IL-2, that activate or augment activation of human peripheral blood T cells by treatment of the analog 5-azacytidine. Over 1 microM of 5-azacytidine, we detected significant inhibition of proliferative response and over 5 microM of 5-azacytidine toxic effect of cell viability. We found no significant change of T cell subsets after treatment of 5-azacytidine.

Adult↗