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Biomedical subjects

S Hibi

Publications and source records attributed to S Hibi.

At least 91 records · Page 5Linked to original sources
PubMed1995

A novel type of retinoic acid receptor antagonist: synthesis and structure-activity relationships of heterocyclic ring-containing benzoic acid derivatives.

A new series of heterocyclic ring-containing benzoic acids was prepared, and the binding affinity and antagonism of its members against all-trans-retinoic acid were evaluated by in vitro assay systems using human promyelocytic leukemia (HL-60) cells. Structure-activity relationships indicated that both an N-substituted pyrrole or pyrazole (1-position) and a hydrophobic region, with these linked by a ring system, were indispensable for effective antagonism. Among the compounds evaluated, optimal antagonism was exhibited by 4-[4,5,7,8,9,10-hexahydro-7,7,10,-10-tetramethyl-1-(3- pyridylmethyl)anthra[1,2-b]pyrrol-3-yl]benzoic acid (31), 4-[4,5,7,8,9,10-hexahydro-7,7,10,10-tetramethyl-1-(3-pyridylmethyl)-5- thiaanthral[1,2-b]pyrrol-3-yl]benzoic acid (40), and 4-[4,5,7,8,9,10-hexahydro-7,7,10,10-tetramethyl-1-(3- pyridylmethyl)anthra[2,1-d]pyrazol-3-yl]benzoic acid (55), all of which possess a 3-pyridylmethyl group at the five-membered ring nitrogen atom.

Benzoates↗
PubMed1995

Serum and urine beta-2-microglobulin in hemophagocytic syndrome.

BACKGROUND: Previous reports suggesting a correlation between lymphoproliferative disease and serum levels of beta-2-microglobulin (beta-2M) and in vitro data indicating a role of cytokines in the production of beta-2M prompted a study of serum and urine beta-2M concentration in patients with hemophagocytic syndrome (HPS), because no data were previously available for HPS, a pathologic state associated with excessive cytokines secreted from activated reactive/malignant lymphocytes and histiocytes. METHODS: Serum and urine beta-2M levels were measured in six children with HPS during active and convalescent phase and in other diseases. RESULTS: Serum and urine beta-2M levels during active phase HPS were significantly high not only in serum (median, 7.5 mg/l; range, 2.3-16.0 mg/l; P < 0.01), but also in urine (median, > 31,650 micrograms/gram Creatinine (gCr); range, 8179-236,333 micrograms/gCr; P < 0.01), compared with levels during convalescent phase HPS (median, 2.0 mg/l; range, 0.9-2.5 mg/l in serum and median, 338 micrograms/gCr; range, 223-585 micrograms/gCr in urine) and in control subjects with diseases such as acute lymphocytic leukemia (median, 2.3 mg/l; range, 1.0-2.8 mg/l in serum and median, 327 micrograms/gCr; range, 48-2684 micrograms/gCr in urine), infectious mononucleosis (median, 2.9 mg/l; range, 2.5-5.5 mg/l in serum and median, 348 micrograms/gCr; range, 80-1325 micrograms/gCr in urine), and Kawasaki disease (median, 2.8 mg/l; range, 1.5-3.3 mg/l in serum and median, 1016 micrograms/gCr; range, 214-4500 micrograms/gCr in urine). Noteworthy was the observation that urine beta-2M levels correlated closely with HPS disease activity. CONCLUSIONS: Urine beta-2M appears to be a useful marker for assessing disease activity in patients with HPS.

Adolescent↗
PubMed1995

Myelodysplasia and acute myeloid leukaemia in cases of aplastic anaemia and congenital neutropenia following G-CSF administration.

Myelodysplasia and acute myeloid leukaemia (MDS/AML) developed in three cases of severe aplastic anaemia (SAA) and one case of congenital neutropenia (CN, Kostmann's disease) who received recombinant human granulocyte colony-stimulating factor (G-CSF) are reported. In these four MDS/AML cases, age at diagnosis of SAA/CN was 0-13 years, the cumulative dose of G-CSF was 98 micrograms/kg to 10 mg/kg over 1-57 months, and the interval from initiation of G-CSF to MDS/AML was 25, 23, 31 and 57 months, respectively. These results suggest a link between SAA/CN and MDS/AML in relation to G-CSF administration; however, large studies are necessary to determine if such a risk is significant in patients with SAA/CN who are treated with G-CSF.

Adolescent↗
PubMed1995

Successful allogeneic bone marrow transplantation in a case with myelodysplastic syndrome which developed following Fanconi anemia.

We report the case of a 14-year-old boy with myelodysplastic syndrome (MDS/RAEB) which developed following Fanconi anemia. The patient received BMT from an HLA-identical sister. Based on the in vitro CY-sensitivity test, 100 mg/kg of CY was administered for conditioning combined with 6 Gy TBI. Mucosal symptoms such as stomatitis, diarrhea and hematuria were severe, but manageable, and engraftment was successful. The patient has maintained normal trilineage hematopoiesis with > 90% Karnofsky score for 30 months with disappearance of a clonal chromosomal abnormality (47,XY, +i(lq)) which was detected before BMT.

Adolescent↗
PubMed1994

Novel dual inhibitors of 5-lipoxygenase and thromboxane A2 synthetase: synthesis and structure-activity relationships of 3-pyridylmethyl-substituted 2-amino-6-hydroxybenzothiazole derivatives.

As part of our search for novel antiinflammatory drug candidates, we have designed and synthesized a series of 3-pyridylmethyl-substituted 2-amino-6- hydroxybenzothiazoles. Introduction of a 3-pyridylmethyl group into the 2-amino group (type-A) or the benzene ring (type-B) of 2-amino-6-hydroxybenzothiazoles imparted dual inhibitory activity against the production by glycogen-induced peritoneal cells of rat (in vitro) of leukotriene B4 (LTB4) and thromboxane A2 (TXA2), while not significantly inhibiting that of prostaglandin E2 (PGE2). The observed inhibition of the former two arachidonic acid metabolites was indicated to be the result of a direct action on 5-lipoxygenase and TXA2 synthetase by a cell-free in vitro assay. On the other hand, the inhibitory activities against PGE2 production were for most compounds very weak, indicating that they did not inhibit cyclooxygenase. Structure-activity relationship studies concerning the position of the 3-pyridylmethyl group revealed that type-B compounds generally showed about 10-fold stronger inhibitory activity against TXA2 synthetase than type-A compounds. The position of the 3-pyridylmethyl group played an important role in TXA2 synthetase inhibition. When some of these compounds (8, 13a, 26a (E3040), 26b, 27b, and 28b) were orally administered in the rat TNB/ethanol-induced chronic colitis model (100 mg/kg), the production of both LTB4 and TXB2 in the rat colon was reduced (ex vivo). In addition, one type-B compound, 6-hydroxy-5,7-dimethyl-2-(methylamino)-4-(3-pyridylmethyl)benzothiazole (26a), demonstrated a therapeutic effect at treatments of 100 mg/kg po once daily for 11 days and showed almost comparable activity to sulfasalazine at a dose of 500 mg/kg, the reference drug for inflammatory bowel diseases, in this in vivo model.

Animals↗
PubMed1994

Haemophagocytic lymphohistiocytosis, interferon-gamma-naemia and Epstein-Barr virus involvement.

To clarify the correlation between Epstein-Barr virus (EBV) involvement and hypercytokinaemia in haemophagocytic lymphohistiocytosis (HLH), we analysed serum interferon-gamma levels and EBV-DNA in biological specimens obtained from 25 HLH cases (23 children and two adults). We found that HLH patients showed a wide range of serum IFN-gamma levels from 0.2 to 1300 U/ml, with a median 126 U/ml for EBV-DNA-positive (n = 9) and 4.5 U/ml for EBV-DNA-negative (n = 16) groups. The latter group could be classified further into a group with hyper-IFN-gamma-naemia (> 4.5 U/ml) (n = 8) and a group without hyper-IFN-gamma-naemia (n = 8). The survival of the hyper-IFN-gamma-naemic cases was significantly poorer than non-hyper-IFN-gamma-naemic cases. We conclude that EBV is probably involved in one third of the HLH cases, all of whom show hyper-IFN-gamma-naemia, and in the half of the HLH cases with hyper-IFN-gamma-naemia who have a rapidly fatal outcome.

Adolescent↗
PubMed1993

Induction of monocytic differentiation and tumorigenicity by v-Ha-ras in differentiation arrested hematopoietic cells.

Activated ras genes are often associated with human myeloid leukemias with a monocytic differentiated phenotype. To investigate the role of the activated ras gene in leukemogenesis, a myeloid nontumorigenic cell line (FDC-P1) was infected with a selectable retroviral vector carrying the v-Ha-ras gene (H1neo). Infected FDC-P1 cells were not only tumorigenic, but also showed increased monocytic differentiation in vitro. Monocytic differentiation and tumorigenicity in vivo were correlated with several-fold increased levels of activated ras gene expression. Tumorigenic cells were arrested with respect to monocytic marker expression at a much later stage of macrophage differentiation than the parental noninfected FDC-P1 cells. These data thus suggest a model of how activated ras genes could be involved in the preferential induction of hematopoietic malignancies with a myelomonocytic phenotype.

Animals↗
PubMed1993

Hypercytokinemia in hemophagocytic syndrome.

PURPOSE: The study was performed to clarify in the hemophagocytic syndrome (HPS) how cytokinemia plays a role in its pathogenesis and if cytokinemia is of prognostic value. PATIENTS AND METHODS: Serum concentrations of ferritin, interferon (IFN)-gamma, soluble interleukin-2 (IL-2) receptor, IL-6, and other cytokines were determined during the acute phase of the HPS in 29 children and three adults. Data comparing malignancy-associated (MAHS; n = 17) and infection-associated hemophagocytic syndrome (IAHS; n = 15) and those comparing surviving and fatal cases were assessed. RESULTS: Hyperferritinemia and hypercytokinemia were present in all patients with HPS. Eleven of the 17 MAHS and three of the 15 IAHS cases were fatal (p < 0.05). No significant difference in cytokine concentrations was observed between MAHS and IAHS. CONCLUSIONS: In terms of cytokine effect on patient outcome, serum concentrations of IL-6 > 300 ng/L and IFN-gamma concentrations > 30 U/ml or soluble IL-2 receptor (sIL-2R) concentrations > 10,000 U/ml were considered to reflect a poor prognosis in HPS patients.

Adolescent↗
PubMed1993

Increase in T cells bearing the gamma/delta receptor associated with lymphoproliferative disease of granular lymphocytes in an infant with intractable diarrhea.

A two-year-old infant with intractable diarrhea and lymphoproliferative disease of granular lymphocytes attributed to a persistent cytomegalovirus infection showed an increase in cells bearing the gamma/delta T-cell receptor (TCR), which accounted for approximately 20% of total peripheral blood lymphocytes and 40% of CD3+ T cells. Of the gamma/delta TCR+ cells, two-thirds were double negative (CD4-/CD8-) and the other one-third CD8 positive. The majority of gamma/delta+ cells were delta TCS 1 positive. The predominance of delta TCS 1 positive cells was also confirmed on biopsy of lymphoid tissues from the colon. After improvement of watery diarrhea and malnutrition following three-month hyperalimentation, the number of gamma/delta TCR+ cells decreased. The patient subsequently died of pneumonia at the age of 2 years and 11 months. A possible site-specific role for the gamma/delta TCR+ cells, particularly delta TCS 1+ cells, in the human intestine is discussed.

Child, Preschool↗
PubMed1993

Second cutaneous neoplasms after acute lymphoblastic leukemia in childhood.

Two cases of second cutaneous neoplasms, one with adenoid cystic carcinoma of the skin and the other with basal cell carcinoma, both occurring 7 years after treatment for childhood acute lymphoblastic leukemia (ALL) are reported. Although such cutaneous neoplasms are generally reported in patients over 40 years of age, our cases, which were diagnosed at the ages of 9 and 14, are the first report of the occurrence of such cutaneous neoplasms following ALL. The neoplasms arose from the scalp of two patients who had received cranial irradiation for central nervous system prophylaxis. The possible link between leukemia therapy incorporating irradiation and the pathogenesis of second cutaneous neoplasms in the scalp is discussed.

Carcinoma, Adenoid Cystic↗
PubMed1993

Establishment and characterization of a human neuroblastoma cell line derived from a brain metastatic lesion.

We encountered a case of abdominal primary stage IV neuroblastoma which recurred in the central nervous system. A neuroblastoma cell line, designated KP-N-NS, was established from this brain metastatic lesion. This is considered to be the first neuroblastoma cell line established from a brain metastatic lesion. In culture, KP-N-NS exhibited N(neuroblastic) type cell morphology with neurite-like processes and small cell bodies. This cell line revealed karyotypic abnormality, 46, XX, -1, +der (1)t(1;?)(p36.1;?), and twelve-fold amplification of MYCN DNA (twice as much in primary bone marrow tumor cells). Integrin study indicated high expression levels of alpha 1 beta 1 and alpha 4 beta 1, but alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1, alpha 6 beta 1, alpha 6 beta 4, and alpha v beta 3 were barely detectable by fluorescence-activated cell sorting (FACS) analysis. Compared with 8 other previously established N-type neuroblastoma cell lines, no significantly characteristic integrin expression was detected in this cell line. KP-N-NS will provide a useful tool for the study of metastasis and relapse in the central nervous system in neuroblastoma patients.

Brain Neoplasms↗
PubMed1993

[Intensive chemotherapy for alveolar soft part sarcoma with lung metastasis in a child].

Alveolar soft part sarcoma (ASPS) is one of the soft tissue sarcomas characterized by metastasis early in the course of the disease, regardless of slow tumor growth. The ultimate clinical outcome is, therefore, very poor. To date, the efficacy of combination chemotherapy for this tumor has not been confirmed. We present a case of ASPS in an 8-year-old boy with bilateral pulmonary metastasis who received systemic combination chemotherapy (CPM/IFO/ACD/ADR/CD DP/VP-16 as induction, and VCR/ACD as maintenance therapy) for eleven months. The result showed that despite the prevention of tumor progression, such intensive chemotherapy could not cure the disease. Besides refinement of chemotherapy regimens, immunotherapy might be considered for ASPS.

Antineoplastic Combined Chemotherapy Protocols↗