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81.
Ichiro Azuma Mikio Yamawaki Kosei Yasumoto Yuichi Yamamura 《Cancer immunology, immunotherapy : CII》1978,4(2):95-100
Summary The antitumor activity of the cell wall skeleton preparations of four species of Nocardia, N. brasiliensis strain 146, N. coeliaca strain 122, N. polychromogenes strain 6, and N. rubra, which showed potent adjuvant activity on the induction of cell-mediated cytotoxicity in allogeneic mice, was examined with the aid of EL-4 leukemia, melanoma B16, and MH-134 hepatoma in syngeneic mice. Preliminary clinical trials were performed and the results suggest that the cell wall skeleton of N. rubra, upon intrapleural injection, may be useful as an immunotherapeutic agent for patients with malignant pleurisy. The chemical properties of these cell wall skeleton preparations are described. 相似文献
82.
T D Reisine J Z Fields L Z Stern P C Johnson E D Bird H I Yamamura 《Life sciences》1977,21(8):1123-1128
To detect variations in dopaminergic receptors and cholinergic activity in regions of postmortem Huntington's diseased brains, 3H-spiroperidol binding assays and choline acetyltransferase (ChAc) activities were carried out. A significant reduction in 3H-spiroperidol binding in the caudate nucleus, putamen and frontal cortex of choreic brains was detected which appeared to be due to a decrease in the total number of binding sites rather than to a decrease in affinity of 3H-spiroperidol for the dopaminergic receptor. In choreic brains, there were also significant reductions in ChAc activity in the caudate nucleus and putamen. The decreases of both 3H-spiroperidol binding and ChAc activity in the neostriatum suggest that the dopaminergic receptors are localized postsynaptically on cholinergic interneurons. Dopaminergic receptor alterations in the basal ganglia may be one of the causes of the abnormal motor movements found in HD while alterations of these receptors in the frontal cortex may be associated with the neuronal degeneration found in that area of choreic brains. 相似文献
83.
The effect of GABA on in vitro binding of two novel non-benzodiazepines, PK 8165 and CGS 8216, to benzodiazepine receptors in the rat brain 总被引:1,自引:0,他引:1
The effect of gamma-aminobutyric acid (GABA) on the binding of PK 8165, a quinoline derivative, and CGS 8216, a pyrazoloquinoline, was assessed in two different regions of the rat brain. PK 8165, a compound with reported anxiolytic properties, inhibited [3H]-propyl beta-carboline-3-carboxylate labeled receptors in the cerebellum with an IC50 of 844 nM and 370 nM in the absence and presence of micro M GABA, respectively. GABA (100 micro M) was less effective in the cerebral cortex, decreasing the IC50 value from 280 to 197 nM. In saturation isotherm studies with [3H]-CGS 8216, a benzodiazepine receptor antagonist, GABA (100 micro M) induced a small but significant reduction in the apparent affinity of [3H]-CGS 8216 for benzodiazepine receptors in the cerebral cortex but the Bmax was unchanged. 相似文献
84.
Precise and quantitative reversed-phase high performance liquid chromatographic (HPLC) procedures are described which can be used in biogenic amine and neuropeptide research. The amine procedure was applied to various pharmacological matrices including plasma, heart tissue and brain. The use of peptide HPLC as an analytical tool for various neuropeptides is illustrated by studies on des-tyrosine-gamma-endorphin (DT gamma E) metabolism in the brain and the stability of an ACTH (ORG-2766) analogue during a chronic infusion in rats. The power of HPLC as a research tool in peptide pharmacology is described, discussed and demonstrated as an aid in the understanding of the pharmacological effects of exogenous peptides and the function of the brain. 相似文献
85.
The novel pyrazoloquinoline, CGS, 9896, was a potent inhibitor of specific [3H]-flunitrazepam binding in several brain regions with subnanomolar KI values. The inhibition of [3H] propyl beta-carboline-3-carboxylate ([3H]-PCC-) binding by CGS 9896 was enhanced by gamma-aminobutyric acid (GABA) but not by chloride ion. GABA enhancement of CGS 9896 inhibition of [3H]-PCC binding predicts this compound has benzodiazepine (BZD) agonist-type activity. Behavioral studies support this prediction. CGS 9896 was found to protect mice against bicuculline and metrazol induced seizure at doses that did not induce ataxia or sedation. CGS 9896 may represent a class of compounds with potential therapeutic value. The high affinity of this non-BZD compound suggests that CGS 9896 may also be of value as a high affinity ligand for the continued study of BZD receptors. 相似文献
86.
Nitrobacter agilis cytochrome c-550 was purified to an electrophoreticallyhomogeneous state, and some of its properties were determined.The cytochrome showed an absorption peak at 410 nm in the oxidizedform, and peaks at 416, 521 and 550 nm in the reduced form.Its isoelectric point was 8.1 at 5?C. Analysis of the aminoacid composition showed that the cytochrome molecule was composedof 108 amino acid residues, 16 of which were lysine residues. The cytochrome reacted rapidly with N. agilis cytochrome c oxidaseand yeast cytochrome c peroxidase and more slowly with Pseudomonasaeruginosa nitrite reductase and bovine cytochrome c oxidase.The reactivities with these redox enzymes suggested that thecytochrome might be an evolutionary stage between bacterialand eukaryotic cytochromes c. The primary structure of the cytochrome from the N-terminusto the 85th residue was determined. The N-terminal sequencewas homologous to the corresponding portion of the primary structureof horse cytochrome c.
1 Present adress: Department of Chemistry, Faculty of Science,Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo,152, Japan. (Received December 3, 1981; Accepted January 28, 1982) 相似文献
87.
Induction of proliferation and Ig production in human B leukemic cells by anti-immunoglobulins and T cell factors 总被引:20,自引:0,他引:20
K Yoshizaki T Nakagawa T Kaieda A Muraguchi Y Yamamura T Kishimoto 《Journal of immunology (Baltimore, Md. : 1950)》1982,128(3):1296-1301
The proliferation and differentiation of human leukemic B cells (B-CLL cells) with anti-Ig and T cell-derived helper factors are described. Stimulation of B-CLL cells with anti-Ig and T helper factors could induce proliferation as well as differentiation into IgM- and IgG-producing cells. Neither anti-Ig nor T helper factors alone could induce any proliferation and/or differentiation of B-CLL cells. Not only whole molecules of anti-Ig but also F(ab')2 fragments could induce proliferation and differentiation of B-CLL cells in the presence of T helper factors, but monovalent Fab' fragments were not effective. Induction of both IgM and IgG with the same idiotype was confirmed by immunofluorescent and SDS-PAGE analysis. By employing an IL 2-dependent cytotoxic T cell line and a TRF-responsive B cell line, T cell factors were separated into a fraction with IL2 activity but no TRF activity and a fraction with TRF activity but no IL 2 activity by chromatofocusing. Anti-Ig and IL 2 fraction could induce proliferation of B-CLL cells, but TRF fraction was not effective for the induction of proliferation in anti-IG-stimulated cells. For IgM and IgG production, anti-Ig and both IL 2 and TRF fractions were required. Depletion of IL 2 fraction in the first 2 days' culture inhibited Ig production, whereas the absence of TRF fraction in the first 2 days did not show any inhibitory effect on Ig production. 相似文献
88.
DNA replication patterns of individual chromosomes and their various euchromatic and heterochromatic regions were analyzed by means of quantitative autoradiography. The cultured cells of the skin fibroblast of a male Indian muntjac were pulse labeled with 3H-thymidine and chromosome samples were prepared for the next 32 h at 1–2 h intervals. A typical late replication pattern widely observed in heterochromatin was not found in the muntjac chromosomes. The following points make the DNA replication of the muntjac chromosomes characteristics: (1) Heterochromatin replicated its DNA in a shorter period with a higher rate than euchromatin. (2) Two small euchromatic regions adjacent to centromeric heterochromatin behaved differently from other portions of euchromatin, possessing shorter Ts, higher DNA synthetic rates and starting much later and ending earlier their DNA replication. (3) Segmental replication patterns were observed in the chromosomes 2 and 3 during the entire S phase. (4) Both homologues of the chromosome 3 showed a synchronous DNA replication pattern throughout the S phase except in the distal portion of the long arms during the mid-S phase. 相似文献
89.
Y Morimoto T Oishi N Hanasaki A Miyatake K Noma Y Yamamura 《Endocrinologia japonica》1980,27(5):659-666
The relative potency in the hypothalamic-pituitary-adrenal (HPA) suppression of both prednisolone and betamethasone was examined in an acute study with normal volunteers and in a chronic study with glucocorticoid-treated patients. Circadian rhythm of plasma cortisol was studied after a single dose administration of 5 to 30 mg prednisolone or 0.5 to 3.0 mg betamethasone at 8:00 hr. Morning-rise of plasma cortisol occurred on the morning after the administration of 30 mg or less prednisolone but no morning rise was noted after the administration of 1.0 mg or more betamethasone. Plasma ACTH was slightly elevated on the morning after 30 mg prednisolone administration but showed low levels throughout the night after 3.0 mg betamethasone administration. Plasma cortisol responsiveness to ACTH was examined in patients before and during therapy with either prednisolone or betamethasone. The basal cortisol level was not suppressed and the responsiveness to ACTH remained nearly normal during long-term 5 mg prednisolone therapy, but these were completely suppressed during long-term 5 mg betamethasone therapy. The responsiveness to ACTH was nearly normal in patients receiving alternate-day therapy with prednisolone in such large doses as 50 or 60 mg every other day, but was completely suppressed in patients receiving 1.0 mg betamethasone every other day. The relative potency of betamethasone in acute and chronic suppressive effects on the HPA system seems to be much stronger than that of prednisolone in equivalent doses with comparable anti-inflammatory effects. It is also suggested that the alternate-day therapy with such long-acting steroids as betamethasone are useless in preventing HPA suppression. 相似文献
90.