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1.
In designing new DNA recognizing and cleaving reagents, we introduce herein a bisacridine derivative (referred to as bisacridine) in which two acridine heterocycles are connected by a penta(ethylene glycol) bridging chain. This compound offers two possible functions: 1, stabilization of DNA bisacridine intercalator complex by metal ion. The penta(ethylene glycol) chain stabilizes metal ions binding to the phosphate site of DNA, where the penta(ethylene glycol) chain constitutes a part of a pseudomacrocyclic ligand for metal binding; and 2, enhancement of metal-assisted hydrolytic cleavage of DNA by means of a metal concentration effect by the pseudomacrocyclic ethereal chain. The binding isotherms of bisacridine with DNA in the presence of metal ions showed that the binding was mainly governed by the cation exchange reaction on the anionic DNA polymer chain, i.e., the exchange between metal ions and the cationic bisacridine. The bisacridine showed an increase DNA binding ability compared to quinacrine, the monoacridine counterpart, and caused an enhancement of DNA cleavage in the presence of Cu2+ ions. Additional experiments which included DNase 1 footprinting in the presence of bisacridine and the DNA cleavage by Cu2+/bisacridine using a 32P end-labelled DNA fragment, suggested that the Cu2(+)-assisted DNA cleavage sites in the presence of bisacridine were in reasonable overlap with the DNA binding sites of bisacridine. 相似文献
2.
Immature Wistar rats were induced to ovulate by treatment with PMSG and hCG. Control animals ovulated 43.5 +/- 0.36 ova/rat. Intraperitoneal injection of rotenone doses of 0.125, 0.25 and 0.50 mg/kg reduced the ovulation rate to 24.0 +/- 3.08, 8.0 +/- 0.88 and 1.5 +/- 0.44 ova/rat, respectively. The rotenone significantly reduced ovarian cytochrome oxidase activity and progesterone production, but not production of oestradiol or testosterone. Thyroxine treatment at a dose of 5 mg/kg s.c. reversed the rotenone inhibition of ovulation. The results suggest that an increase in mitochondrial respiration is an essential feature of the ovulation process in mammals. 相似文献
3.
Y Murayama T Ishida M Minezawa A Noguchi O Takenaka 《Journal of medical primatology》1988,17(1):31-40
A cell line (JAMH17+) resistant to 8-azaguanine was established from a human T-cell leukemia virus type 1 related virus (simian T-cell leukemia virus-1) positive Japanese macaque cell line. Lymphoblastic cell lines were established from the peripheral blood mononuclear cells of humans, hominoids, and several species of macaques by coculture with JAMH17+ in hypoxanthine-aminopterin-thymidine medium. HTLV-1 specific antigen was detected in some of the established cell lines. Phenotypic analysis showed that several cell lines of crab-eating macaques expressed Leu11a antigen, which is a marker of human natural killer cells. 相似文献
4.
Amino acid sequences of fibrinopeptides A and B from the macaque, Macaca fuscata (Japanese monkey) and the guenon, Erythrocebus patas (patas monkey) were established. Fibrinopeptides A of the monkeys had a sequence identical with those of baboons: Ala-Asp-Thr-Gly-Glu-Gly-Asp-Phe-Leu-Ala-Glu-Gly-Gly-Gly-Val-Arg. Fibrinopeptides B were 9-residue, "short," peptides with the sequences Asn-Glu-Glu-Ser-Leu-Phe-Ser-Gly-Arg for M. fuscata and Asn-Glu-Glu-Val-Leu-Phe-Gly-Gly-Arg for E. patas. The sequence of the B peptide of M. fuscata differed from that of a close-related species, M. mulatta (rhesus monkey), at a single site, Leu (M.f.)----Pro (M.m.). A single replacement between the B peptides of E. patas and Cercocebus aethiops (green monkey), Val (E.p.)----Gly (C.a.), was detected. A phylogenic relationship of macaques, guenons, and baboons, named Cercopithecinae (Old World monkey), was deduced from the sequence data. A selective rather than random amino acid replacement was observed in the B peptides of these Old World monkeys, suggesting a restricted mutation of their fibrinopeptides during primate evolution. 相似文献
5.
Epitope expression on primate lymphocyte surface antigens 总被引:1,自引:0,他引:1
The cross-reactivity of peripheral blood mononuclear cells from 28 nonhuman primates was investigated with ten kinds of Leu series of monoclonal antibodies specific to human T-, natural killer/killer-, and B-cells. The chimpanzees possessed all ten epitopes examined but the orangutan lacked Leu4 and Leu7 epitopes and the gibbons lacked Leu4, Leu7, and Leu12 epitopes. In addition to the above epitopes, the Old World monkeys lacked Leu1 and Leu10 epitopes. The Leu3a/Leu2a cell ratios varied from 0 to 1.56 among the 12 macaque species and this enabled classification of these species into three groups. In the New World monkeys, Leu2a epitope was absent, whereas Leu11a epitope was detected in several species and Leu3a epitope was found only in the owl monkeys. The prosimians expressed only HLA-DR epitope. 相似文献
6.
Mirik A. Suleymanian Toshifumi Takenaka Khachik V. Stamboltsyan Sinerik N. Ayrapetyan 《Cellular and molecular neurobiology》1986,6(2):151-163
The effects of short-chain fatty acids on the membrane excitability, current-voltage (I-V) characteristics, and cell volume of Helix pomatia neurons were studied. 2-Decenoic acid (DA), having 10 carbon atoms in the hydrocarbon chain, suppressed the excitability of bursting neurons RPa1 (Sakharov and Salanki, 1969) for 30-60 min, while valeric acid (VA), having 5 carbon atoms, had no significant effect on excitability. DA had three different effects on the excitability of beating neurons: in some neurons DA suppressed excitability as in bursting neurons; in a second type of neuron DA had a negligible effect on excitability; and in the neuron located near RPa1 DA had a pentylentetrazol (PTZ)-like effect, i.e., it converted the discharge of the neuron from beating to bursting. DA decreased the peak value of the current, inducing a negative-resistance region in the I-V curve of the bursting neuron without any change in the level of the voltage at which the current reaches its maximal value. DA inhibited the hyperpolarization induced by activation of the Na+ pump, tested after preliminary enrichment of neurons with Na+ ions by incubation in a potassium-free solution for 20 min. DA caused a swelling of the neuron by about 10% which was independent of the Na+ pump. In all the above-mentioned cases VA had no significant effect. 相似文献
7.
A radioimmunoassay for progesterone was developed which uses one micro-column chromatography for purification of hexane extracts of plasma. 相似文献
8.
9.
Y. Ohtsuki T. Yamaguchi H. Sonobe K. Takahashi K. Hayashi A. Takenaka H. Hashimoto K. Kuwabara T. Miyamoto N. Terao 《Biotechnic & histochemistry》1989,64(2):55-59
A new simplified method has been devised for staining aluminum and has been tested in paraffin sections of bone from 60 patients who have undergone hemodialysis. Iliac crest bone fragments were fixed in 20% phosphate-buffered formalin for less than a day and demineralized at room temperature in 10% phosphate-buffered formalin containing 5% formic acid for only 2 to 3 hr. Four-micron paraffin sections, accompanied by positive controls, were stained with Maloney's aluminum stain, the Berlin blue reaction for iron, dylon or Congo red for amyloid and von Kossa's reaction for calcium. Aluminum and iron were demonstrated particularly at the mineralizing front of bony tissues; aluminum in 52 cases, iron in 45. Dylon staining also gave positive results in 52 cases. It is important in determining whether aluminum deposition is present that the von Kossa reaction remains positive even after demineralization. This method may be more useful for demonstrating aluminum in bony tissues than the complicated and time-consuming resin-embedding method currently used. 相似文献
10.