Biomedical subjects

Y Sonoda

Publications and source records attributed to Y Sonoda.

At least 19 recordsLinked to original sources

PubMed1992

Structural analysis of the interaction between the side-chain of substrates and the active site of lanosterol 14 alpha-demethylase (P-450(14)DM) of yeast.

The role of the side-chain of lanosterol in the enzyme-substrate interaction of yeast P-450(14)DM (lanosterol 14 alpha-demethylase) was analyzed with lanosterol derivatives having functional groups on the side-chain. Purified P-450(14)DM from Saccharomyces cerevisiae catalyzed 14 alpha-demethylation of 26-hydroxylanosterol and 25-hydroxy-24,25-dihydrolanosterol with a lower activity than lanosterol and 24,25-dihydrolanosterol. This enzyme demethylated the (Z)-24-ethylidene-24,25-dihydrolanosterol with a low rate, but did not metabolize the E-isomer. The apparent Km of 26-hydroxylanosterol was 10.8 microM, which was higher than that of lanosterol, but lower than that of 24,25-dihydrolanosterol. On the other hand, competition experiments suggested that the affinity of 25-hydroxy-24,25-dihydrolanosterol and (Z)-24-ethylidene-24,25-dihydrolanosterol for P-450(14)DM was significantly lower than that of 24,25-dihydrolanosterol. Integration of the present results with the preceding ones (Aoyama, Y., Yoshida, Y., Sonoda, Y. and Sato, Y. (1991) Biochim. Biophys. Acta, 1081, 262-266 and Aoyama, Y. and Yoshida, Y. (1991) Biochem. Biophys. Res. Commun., 178, 1064-1071) suggests that yeast P-450(14)DM recognizes two parts of the side-chain, the structure around C-24 and the terminal fork consisting of C-25, C-26 and C-27.

Binding Sites↗

PubMed1992

Human interleukin-9 supports formation of a subpopulation of erythroid bursts that are responsive to interleukin-3.

We have investigated the biological activities of recombinant human interleukin-9 (IL-9) on enriched hematopoietic progenitors, alone or in combination with other cytokines, including Epo, G-CSF, IL-3, and GM-CSF, under serum-containing and serum-free cultures. IL-9 alone did not support colony formation. However, IL-9 plus Epo induced erythroid burst (BFU-E) formation derived from peripheral blood (PB) progenitors. Delayed addition experiments demonstrated that a part of bone marrow (BM) derived BFU-E, which seems to be immature, only responded to IL-9 and formed erythroid bursts. The burst-promoting activity (BPA) of IL-9 was confirmed using neutralizing aIL-3, aGM-CSF, and aIL-9 antisera and serum-free culture. IL-9 supported a part of BFU-E population that respond to IL-3, which was almost identical to the number of BFU-E supported by GM-CSF. IL-9 had no additive effect on erythroid and mixed colony formation supported by IL-3. In contrast, IL-9 showed an additive effect on erythroid burst formation supported by GM-CSF in serum-free culture. These data suggest that IL-9 and GM-CSF act on distinct IL-3-responsive BFU-E population. In addition, delayed addition experiment clearly demonstrated that IL-9 supports survival and the early stage of proliferation of BFU-E. These results led us to propose that IL-9 possibly acts as a BPA and selectively supports a subpopulation of early class of BFU-E that respond to IL-3.

Cell Division↗

PubMed1992

Orthotopic corneal transplantation in mice--evidence that the immunogenetic rules of rejection do not apply.

The fate of orthotopic corneal transplants has been studied in inbred strains of mice. Using a surgical technique that achieves > 95% success of syngeneic cornea grafts, it was determined that a high proportion of orthotopic cornea allografts were accepted indefinitely, irrespective of the degree of immunogenetic disparity between graft donor and recipient. Grafts that succumbed to irreversible rejection developed extensive corneal edema and intrastromal neovascularization as harbingers of corneal opacity and endothelial cell failure. The highest rate of rejection occurred among grafts that confronted their hosts with multiple minor histocompatibility antigens, with or without major histocompatibility antigens. Much lower rates of rejection (< 35%) were observed when the donors of the grafts differed from recipients at class I and/or class II major histocompatibility loci. Corneal grafts that confronted their hosts with class II MHC alloantigens alone experienced early, acute inflammation, and eventually developed stomal neovascularization, but only a small minority of these grafts were eventually destroyed. Allogeneic corneas that were transplanted orthotopically into eyes of presensitized mice were uniformly subjected to an acute rejection process that produced opacity within three weeks; however, in a minority of instances, the inflammation and opacity subside, and after eight weeks the grafts displayed a clear, nonvascularized appearance. The high rate of success of even grossly histoincompatible orthotopic corneal allografts in mice resembles the extraordinary success of unmatched allogeneic corneas transplanted into human eyes. The results are discussed in terms of the possible mechanisms that permit orthotopic corneal allografts to enjoy significantly better survival than orthotopic grafts of other types of solid tissues.

Animals↗

PubMed1992

Bilineage response in refractory aplastic anemia patients following long-term administration of recombinant human granulocyte colony-stimulating factor.

5 patients with refractory aplastic anemia (AA) received long-term administration (2-11 + months) of recombinant human G-CSF (rhG-CSF) in doses from 250-500 micrograms/body/day by intravenous infusion or 75-300 micrograms/body/d by subcutaneous injection. All 5 evaluable patients showed a substantial increase in absolute neutrophil count (ANC) with a recovery of myeloid components in the bone marrow after 1 to 2 months of treatment. Interestingly, 2 out of the 5 patients showed a dramatic improvement in severe anemia after 2 to 4 months of treatment accompanying a recovery of erythroid components in the bone marrow. In addition, there was no serious infection before or during therapy. Long-term administration of rhG-CSF was well tolerated because of its minimal toxicity. Clonal assay revealed a recovery of myeloid progenitors in all patients and a recovery of erythroid progenitors in 3 out of the 5 patients. These results suggest that long-term administration of rhG-CSF at least mobilizes residual myeloid as well as erythroid progenitor cells and induces a bilineage response in severe refractory AA.

Adult↗

PubMed1992

Effects of 32-oxygenated lanosterol derivatives on 3-hydroxy-3-methylglutaryl coenzyme A reductase activity and cholesterol biosynthesis from 24,25-dihydrolanosterol.

The effects of 32-oxygenated lanosterol derivatives on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity and cholesterol biosynthesis from [24,25-3H]24,25-dihydrolanosterol were studied. Among the derivatives, 3 beta-hydroxylanost-7-en-32-oic acid was the most active in depressing HMG-CoA reductase activity (IC50: 0.7 microM) and cholesterol biosynthesis (IC50: 0.4 microM) from 24,25-dihydrolanosterol.

Animals↗

PubMed1992

Ehlers-Danlos syndrome combined with von Recklinghausen neurofibromatosis.

We recently had the opportunity to study a 25-year-old male with both Ehlers-Danlos syndrome (EDS) and von Recklinghausen neurofibromatosis (VRNF). We describe the clinical manifestations of the case and discuss the probable pathomechanism of the combination of the two syndromes, with a review of the literature. As recent literature suggests that both syndromes are linked to chromosome 17, we conclude that their combination is not coincidental, but genetically linked.

Adult↗

PubMed1992

[Clinical significance of recombinant human granulocyte colony-stimulating factor (rG-CSF) in the chemotherapy of patients with malignant lymphoma].

We examined the effects of recombinant human granulocyte colony-stimulating factor (rG-CSF) on neutropenia induced by chemotherapy in 10 patients with non-Hodgkin's lymphoma (NHL). The numbers of peripheral blood hematopoietic progenitors were also evaluated before and after administration of rG-CSF. Six patients received an administration of 2 micrograms/kg/body weight of rG-CSF subcutaneously for 14 days after 2nd chemotherapy. Four patients received intravenous infusion of rG-CSF (300 micrograms/body/day) for 4 days from nadir state after chemotherapy. Administration of rG-CSF from the termination of chemotherapy, markedly shortend the period of bone marrow hypoplasia induced by chemotherapy. On the other hand, administration of rhG-CSF from nadir state after chemotherapy have accelerated the recovery of neutrophil counts. In addition, this type of therapy induced 26 to 60 folds increase of peripheral blood hematopoietic progenitors. These results demonstrate the validity of administration of rhG-CSF not only in the chemotherapy of NHL, but also in peripheral blood stem cell transplantation (PBSCT).

Adult↗

PubMed1992

Synergistic suppression of the clonogenicity of U937 leukemic cells by combinations of recombinant human interleukin 4 and granulocyte colony-stimulating factor.

The actions and interactions of purified recombinant human (rh) interleukin 4 (IL-4) and granulocyte colony-stimulating factor (G-CSF) on the clonogenicity of human leukemic cell line U937 were studied in vitro. Parameters analyzed were the suppression of stem cell generation using sequential clonal cultures, alterations of surface antigen expression, and morphological changes. IL-4 alone (10 U/ml) and G-CSF alone (1000 U/ml) only slightly reduced colony numbers (80% +/- 7% and 87% +/- 7% of control colonies, respectively). However, IL-4 interacted synergistically with G-CSF to further reduce the colony number (46% +/- 8% of control colonies) and suppress the self-renewal ability (clonogenicity) of U937 cells. This synergistic effect was not eliminated by cultures containing neutralizing concentrations of anti-granulocyte-macrophage colony-stimulating factor (anti-GM-CSF), anti-interleukin 6 (anti-IL-6), anti-interferon-alpha (anti-IFN-alpha), anti-IFN-gamma, anti-transforming growth factor-beta (anti-TGF-beta) serum, and anti-tumor necrosis factor-alpha (anti-TNF-alpha) serum. The coexistence of IL-4 and G-CSF was required for at least 48 h to reveal the synergistic action as assessed by preincubation and delayed addition experiments. Combinations of IL-4 and G-CSF showed a significant increase in CD11b expression on U937 cells. This action was not observed with HL60, K562, ML-1, or KG-1 leukemic cell lines, and IL-4 did not show any synergistic suppression of clonogenicity of U937 leukemic cells in combination with other cytokines tested in this study. These results suggest that IL-4 in combination with G-CSF may have some capacity to synergistically suppress human leukemic cells of specific types with loss of clonogenicity.

Antibodies↗

PubMed1992

[Function, molecular structure and gene expression regulation of interleukin 9 (IL-9)].

Interleukin-9 (IL-9)/P40 is a recently reported murine growth factor for helper T-cell clones. It is produced by ConA stimulated CD4+ T-cells or several T-cell lines such as TUC 2.15 derived from C57Bl/6 mouse. In the murine system, IL-9/P40 directly supported proliferation of mucosal type mast cells, and also induced erythroid burst formation, indirectly. On the other hand, human IL-9, which is a homologue to murine P40, was cloned from a cDNA library prepared with mRNA isolated from PHA-induced T-cell line (C5MJ2). Analysis of the sequence of cDNA revealed a striking similarity between murine and human IL-9/P40. Human IL-9 supported formation of a subpopulation of erythroid bursts that are responsive to IL-3. In this communication, identification, cloning of cDNA, and biological activities of murine and human IL-9/P40 are discussed.

Animals↗

PubMed1991

Purification and characterization of N-acyl-D-glutamate deacylase from Alcaligenes xylosoxydans subsp. xylosoxydans A-6.

The purification and properties of N-acyl-D-glutamate deacylase from the cell extracts of Alcaligenes xylosoxydans subsp. xylosoxydans A-6 were studied. The two active fractions (peaks I and II) were obtained by a Mono Q column chromatography. The predominant enzyme (peak I) has been purified, 1960-fold to homogeneity and characterized. The enzyme was a monomer with a molecular weight of 59,000. The optimum pH and the isoelectric point were 8.0 and 5.5, respectively. The enzyme catalyzed the hydrolysis of N-acyl derivatives of D-glutamate. The Kms for N-acetyl, N-butyryl and N-propionyl derivatives of D-glutamate were 0.129, 0.066 and 0.01 mM, respectively.

Alcaligenes↗

PubMed1991

Purification and characterization of cytochrome P-45014DM (lanosterol 14 alpha-demethylase) from pig liver microsomes.

Cytochrome P-45014DM, which catalyzes lanosterol 14 alpha-demethylation, from pig liver microsomes was purified to a state of virtually homogeneous by gel electrophoresis. Its apparent monomeric molecular weight was estimated to be 53,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the amino-terminal amino acid sequence was Gly-Leu-Leu-Thr-Gly(Leu)-Asp-Leu-Leu-Gly-Ile. When reconstituted with NADPH-cytochrome P-450-reductase, the enzyme showed a high activity for lanosterol and 24,25-dihydrolanosterol 14 alpha-demethylation. Furthermore, the oxygenated intermediates of 24,25-dihydrolanosterol 14 alpha-demethylation, 32-hydroxy-24,25-dihydrolanosterol and 32-oxo-24,25-dihydrolanosterol, were converted to the 32-nor compound, 4,4-dimethylcholesta-8,14-dien-3 beta-ol, by the reconstituted enzyme system.

Amino Acid Sequence↗

PubMed1991

Role of the side chain of lanosterol in substrate recognition and catalytic activity of lanosterol 14 alpha-demethylase (cytochrome P-450 (14DM)) of yeast.

The 14 alpha-demethylation of 24,25-dihydrolanosterol (DHL) derivatives having trimmed side chains, 27-nor-DHL, 26,27-dinor-DHL, 25,26,27-trinor-DHL, 24,25,26,27-tetranor-DHL, 23,24,25,26,27-pentanor-DHL and 22,23,24,25,26,27-hexanor-DHL, was studied with the reconstituted lanosterol 14 alpha-demethylase system consisting of cytochrome P-450(14DM) and NADPH-cytochrome P-450 reductase both purified from yeast microsomes. The demethylase catalyzed the 14 alpha-demethylation of the derivatives having the side chains longer than tetranor but the activities for the trinor- and tetranor-derivatives were lower. Kinetic analysis indicated that affinity of the trinor-derivative for the demethylase was considerably higher than that of DHL. The affinities of the 27-nor- and dinor-derivatives were increased by this order and were the intermediates of DHL and the trinor derivative. On the other hand, Vmax values of the demethylase for the DHL derivatives were decreased depending on their side-chain lengths, and the substrate-dependent reduction rate of cytochrome P-450(14DM) was also decreased in the same manner. Based on these observations, it was concluded that interaction of the side chain of lanosterol especially C-25, 26 and 27 with the substrate site of lanosterol 14 alpha-demethylase was necessary for enhancing the catalytic activity of the enzyme. However, this interaction was considered not to be essential for substrate binding.

Catalysis↗

PubMed1991

Treatment of idiopathic neutropenia in the elderly with recombinant human granulocyte colony-stimulating factor.

We administered recombinant human granulocyte colony-stimulating factor (rhG-CSF) intravenously for 2 weeks to 2 elderly patients with severe neutropenia. The absolute neutrophil count (ANC) recovered promptly after the initiation of rhG-CSF therapy and reached a peak (greater than 10 x 10(9)/l) on the 13th day. The ANC fell rapidly after rhG-CSF was discontinued, but it remained within the normal range after therapy. There were no side effects during the entire course of treatment. Therefore, rhG-CSF seems to be a most beneficial treatment in elderly patients with severe neutropenia.

Acute Disease↗

PubMed1991

Synthesis of lanosterol derivatives with a functional group at C-32, including an antineoplastic sterol, 3 beta-hydroxylanost-7-en-32-oic acid.

Lanosterol derivatives with a functional group at C-32 have been synthesized from 3 beta-acetoxylanostan-7 alpha-ol. The key reaction of the synthesis is the hypoiodite reaction of 3 beta-acetoxylanostan-7 alpha-ol. In vitro antitumor activity testing of the lanosterol derivatives revealed that 3 beta-hydroxylanost-7-en-32-oic acid has antineoplastic activity.

Animals↗

PubMed1991

[Respiratory failure and its care in Duchenne muscular dystrophy].

Respiratory failure is the major cause of death in patients with Duchenne muscular dystrophy (DMD). In this report we retrospectively examined the clinical courses, pulmonary function, progression of scoliosis and the time of assisted ventilation. Forty nine patients, aged 2 to 27 years were studied and thirty eight patients of them were examined twice in some intervals. The subjects of examinations included pulmonary function studies consisting of spirometry, measurement of the thoracic scoliosis measured according to the method of Cobb and room air arterial blood gas values. The results were the following; 1) The decline in percentage values of vital capacity (%VC) began at age 8 or 9 and decreased consistently with age. Finally %VC reached under 10 percent at mean age of 21.53 with respiratory failure. 2) Thoracic scoliosis measured according to the method of Cobb increased further with advancing age. The greater the angle of curvature, the more likely the development of respiratory failure. 3) Sixteen patients received negative pressure ventilator (chest respirator: CR) between 16.5 and 25.1 years of age. Twelve patients used part-time (mainly night-time) ventilator and four patients used it in full-time. The average PaCO2 and PaO2 before administration of ventilator were 67.49 mmHg and 71.46 mmHg, respectively. The levels after ventilation were 58.01 mmHg (PaCO2) and 82.09 mmHg (PaO2).

Adolescent↗

PubMed1990

Actions of human interleukin-4/B-cell stimulatory factor-1 on proliferation and differentiation of enriched hematopoietic progenitor cells in culture.

We studied the effects of recombinant human interleukin-4 (IL-4) on colony formation by enriched hematopoietic progenitors. IL-4 alone did not support colony formation at all. When IL-4 was combined with granulocyte colony-stimulating factor (G-CSF), the number of pure neutrophil colonies increased three times over that supported by G-CSF alone. IL-4 added 5 days after the addition of G-CSF failed to exert this synergistic effect, indicating that IL-4 acts on the early stage of proliferation. The mapping experiments (sequential observation of colony formation) have clearly shown that IL-4 did not initiate progenitor cell proliferation. Based on these data, IL-4 may possess a direct action on progenitor cells; however, it can only act as a costimulant with G-CSF. In contrast, IL-4 had possible inhibitory effects on macrophage colony formation supported by interleukin-3 (IL-3) and macrophage colony-stimulating factor (M-CSF). In other words, IL-4 may induce progenitor cells to become sensitive to G-CSF and thereby induce neutrophil differentiation. Delayed addition experiments demonstrated that human IL-4, unlike murine IL-4, could support neither proliferation nor survival of erythroid burst or mixed colony forming cells. Neutrophil colony forming cells only survived and recovered after addition of G-CSF and erythropoietin on day 5 of incubation. On the other hand, IL-3 supported neutrophil, erythroid burst, and mixed colony forming cells as reported previously (Sonoda et al, Proc Natl Acad Sci USA, 85:4360, 1988). These results led us to propose that IL-4 possibly acts with more mature progenitor cells than those of IL-3 or granulocyte-macrophage (GM)-CSF.

Bone Marrow↗

PubMed1990

Temperature modulation of photoperiodically induced LH secretion and its termination in Japanese quail (Coturnix coturnix japonica).

Long days induced LH release in photosensitive Japanese quail and ambient temperature did not affect this process. Temperature also did not affect the levels of circulating LH concentrations at the steady state of LH release on long days. On the other hand, low ambient temperature was required to reduce circulating LH to a nonbreeding level together with the change of the photoperiod from long to short days; the changes of the photoperiod without low ambient temperature induced a decrease of circulating LH only to a certain level (1-2 ng/ml) which could maintain reproductive activity. The results also indicated that there were three levels of circulating LH in quail which were tentatively designated as a nonbreeding level (less than 0.5 ng/ml), a basal breeding level (1-2 ng/ml), and a steady breeding level (ca. 4 ng/ml). By photostimulation, levels of circulating LH increased to the steady breeding level directly and gradually, or leveled off after overshooting it. Photoperiodic changes from long to short days under moderate temperature resulted in a decrease in circulating LH to the basal breeding level which, however, could keep the gonad and the accessory sex organs active. Photoperiodic changes under cold ambient temperature reduce circulating LH to the nonbreeding level at which the gonad and the accessory sex organs regressed completely. These results suggest that ambient temperature is involved in the mechanism controlling an annual reproductive cycle, especially at the termination of the reproductive activity, in Japanese quail.

Animals↗

PubMed1990

Granulocyte medullasin levels in gingival crevicular fluid from chronic adult periodontitis patients and experimental gingivitis subjects.

The concentration of medullasin, an elastase-like serine proteinase, in gingival crevicular fluid (GCF) from chronic adult periodontitis patients and experimental gingivitis subjects was determined by the highly sensitive immunoassay method. In periodontitis patients, the medullasin content increased with increase of the GCF volume and then attained a maximum value at a relatively mildly inflamed stage. The value was maintained through more serious stages of disease activity. However, the medullasin content was independent of the probing depth. The medullasin content of the patients was markedly decreased after periodontal treatment, indicating that the enzyme participates in the development of the chronic periodontitis. Large amounts of medullasin were also detected in GCF from experimental gingivitis subjects, although it was not detected by the activity measurements. There was a rapid increase in the medullasin content during the 4-day period after abstention from oral hygiene measures, which corresponded to those of severely inflamed periodontitis patients. The peak value decreased up to the 7th-d followed by a gradual increase during the 21-d experimental period. The increased medullasin level rapidly decreased following resumption of oral hygiene measures. The results suggest that medullasin plays important roles both in the defence mechanism against the gingival inflammation and in the development of the acute inflammation.

Adult↗