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61.
Noriaki Inamura Saburo Sone Akio Okubo Eiji Kunishige Mie Nakanishi Takeshi Ogura 《Cancer immunology, immunotherapy : CII》1989,28(3):164-170
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL
interleukin
- IFN
interferon
- TNF
tumor necrosis factor 相似文献
62.
Tadao Niijima Takashi Umeda Manabu Kuriyama Hiroyuki Ohmori Yohsuke Matsumura Tomoyasu Tsushima Toyoko Tanahashi Jun Yoshimoto Toshihiko Asahi Norimasa Ike Taiichiro Johsen Noritaka Ishido Naoki Mitsuhata Takeshi Uyama Hiroyoshi Tanaka Hideo Ueda Jisaburo Sakatoku Norio Yamamoto Kazuo Nagata Yukitoshi Fujita Masaaki Morioka Kazuo Kurokawa Susumu Kagawa Tomoyuki Ishibe Yasutoshi Himeno Toyofumi Ueda 《Cancer immunology, immunotherapy : CII》1989,30(2):81-85
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects. 相似文献
63.
M Shiozaki R Sakai M Tabuchi M Shinohara M Kosaka S Saito Y Eto 《Biochemical and biophysical research communications》1992,183(1):273-279
Activin A/EDF, initially found as a differentiation inducer of murine Friend erythroleukemia, also has a stimulatory effect on erythropoiesis in vitro and in vivo. Here we proved activin A/EDF activity in human serum. The activin A/EDF level in 18 normal human serum samples was measured by a specific bioassay and was found to be 8.3 +/- 4.6 ng/ml, indicating that there exists sufficient activity to affect erythropoiesis in normal serum. In contrast, activin A/EDF activity was reduced in the chronic renal failure patients and 23/26 serum samples examined showed levels below 1.2 ng/ml. Further analysis using HPLC revealed that chronic renal failure serum actually contained as much activin A/EDF as normal serum, and that the difference between normal and patient serum existed in the content of a specific inhibitor of activin A/EDF. This observation suggests the possibility that the inhibitor is participating in the regulation of activin A/EDF activity in vivo in chronic renal failure patients and also the possibility of activin A/EDF could be utilized in the therapy of the anemia of such patients. 相似文献
64.
H Rakugi Y Tabuchi M Nakamaru M Nagano K Higashimori H Mikami T Ogihara 《Biochemistry international》1990,21(5):867-872
The effects of endothelin on the vascular renin-angiotensin system were examined in isolated perfused rat mesenteric arteries by measuring vascular renin activity and angiotensin II released into the perfusate. Infusion of endothelin (10(-9)M and 10(-11)M) increased the vascular renin activity and angiotensin II release. Pretreatment with nicardipine (10(-6)M), a calcium channel blocker, significantly suppressed these effects of endothelin. These results suggest that endothelin activates the vascular renin-angiotensin system via intracellular calcium metabolism. Vascular angiotensin II produced by endothelin may modulate the local effect of endothelin on the resistance vessels. 相似文献
65.
Yuichiro Arai Se KyungKim Hiroyasu Kinemuchi Takeshi Tadano Shinetsu Satoh Nobunori Satoh Katsuyuki Oyama Kensuke Kisara 《Neurochemistry international》1990,17(4):587-592
The present study was carried out mainly to clarify whether the two amphetamine metabolites, p-hydroxyamphetamine (P-OHA) and p-hydroxynorephedrine (p-OHN) are taken up by mouse brain 5-hydroxytryptamine (5-HT) nerve terminals to inhibit type A monoamine oxidase (MAO-A) and then potentiate the abnormal behavior, head-twitch. Of the two metabolites, only intracerebroventricular p-OHA, at 80 μg/mouse, sufficient to cause a head-twitch response (HTR), appreciably inhibited MAO-A activity without affecting MAO-B activity in homogenates of the mouse striatum, hypothalamus and the rest of the forebrain; and p-OHN did not inhibit either type of MAO at the dose tested. Estimation of intra- and extrasynaptosomal MAO-A activity showed that both metabolites significantly inhibited only the intrasynaptosomal deamination of 5-HT by MAO-A with p-OHA being more potent. Taken together with our previous findings, these present results clearly indicate that p-OHA may accumulate in the 5-HT nerve terminals through the uptake system, and concomitantly inhibit MAO-A activity. These actions of p-OHA may increase intraneuronal 5-HT levels and then potentiate 5-HT release to cause interaction with the post-synaptic 5-HT receptors. 相似文献
66.
67.
68.
Zhi-Hui Su Osamu Tominaga Takeshi Ohama Eiji Kajiwara Ryoshuke Ishikawa Tokindo S. Okada Keiko Nakamura Syozo Osawa 《Journal of molecular evolution》1996,43(6):662-671
Molecular phylogenetic analyses using mitochondrial NADH dehydrogenase subunit 5 (ND5) gene sequences representing all 15 species and the majority of subspecies or races of theOhomopterus ground beetles from all over the Japanese archipelago have uncovered a remarkable evolutionary history. Clustering of the species in the molecular phylogenetic tree is linked to their geographic distribution and does not correlate with morphological characters. Taxonomically the same species or the members belonging to the same species-group fall out in more than two different places on the ND5 tree. Evidence has been presented against a possible participation of ancestral polymorphism and random lineage sorting or of hybrid individuals for the observed distribution of mitochondrial DNA haplotypes. The most plausible explanation of our results is that parallel evolution took place in different lineages. Most notably,O. dehaanii, O. yaconinus, andO. japonicus in a lineage reveal almost identical morphology with those of the same species (or subspecies) but belonging to the phylogenetically remote lineages.The nucleotide sequence data reported in this paper will appear in the DDBJ, EMBL, and GenBank nucleotide sequence databases with accession numbers D50711-DD-50733 and D87131-D87186. 相似文献
69.
Hormonal induction of all stages of spermatogenesis in germ-somatic cell coculture from immature Japanese eel testis 总被引:2,自引:1,他引:1
Chiemi Miura Takeshi Miura Masakane Yamashita Kohei Yamauchi Yoshitaka Nagahama 《Development, growth & differentiation》1996,38(3):257-262
In cultivated male eel, spermatogonia are the only germ cells present in testis. Our previous studies using an organ culture system have shown that gonadotropin and 11-ketotestosterone (11-KT, a potent androgen in teleost fishes) can induce all stages of spermatogenesis in vitro. for detailed investigation of the control mechanisms of spermatogenesis, especially of the interaction between germ cells and testicular somatic cells during 11-KT-induced spermatogenesis in vitro, we have established a new culture system in which germ cells and somatic cells are cocultured after they are aggregated into pellets by centrifugation. Germ cells (spermatogonia) and somatic cells (mainly Sertoli cells) were isolated from immature eel testis. Coculture of the isolated germ cells and somatic cells without forming aggregation did not induce spermatogenesis, even in the presence of 11-KT. In contrast, when isolated germ cells and somatic cells were formed into pellets by centrifugation and were then cultured with 11-KT for 30 days, the entire process of spermatogenesis from premitotic spermatogonia to spermatozoa was induced. However, in the absence of 11-KT in the culture medium spermatogenesis was not induced, even when germ cell and somatic cells were aggregated. These results demonstrate that physical contact of germ cells to Sertoli cells is required for inducing spermatogenesis in response to 11-KT. 相似文献
70.
Hidenori Sassa Takeshi Nishio Yasuo Kowyama Hisashi Hirano Takato Koba Hiroshi Ikehashi 《Molecular & general genetics : MGG》1996,250(5):547-557
Stylar riboncleases (RNases) are associated with gametophytic self-incompatibility in two plant families, the Solanaceae and the Rosaceae. The self-incompatibility-associated RNases (S-RNases) of both the Solanaceae and the Rosaceae were recently reported to belong to the T2 RNase gene family, based on the presence of two well-conserved sequence motifs. Here, the cloning and characterization of S-RNase genes from two species of Rosaceae, apple (Malus × domestica) and Japanese pear (Pyrus serotina) is described and these sequences are compared with those of other T2-type RNases. The S-RNases of apple specifically accumulated in styles following maturation of the flower bud. Two cDNA clones for S-RNases from apple, and PCR clones encoding a further two apple S-RNases as well as two Japanese pear S-RNases were isolated and sequenced. The deduced amino acid sequences of the rosaceous S-RNases contained two conserved regions characteristic of the T2/S-type RNases. The sequences showed a high degree of diversity, with similarities ranging from 60.4% to 69.2%. Interestingly, some interspecific sequence similarities were higher than those within a species, possibly indicating that diversification of S-RNase alleles predated speciation in the Rosaceae. A phylogenetic tree of members of the T2/S-RNase superfamily in plants was obtained. The rosaceous S-RNases formed a new lineage in the tree that was distinct from those of the solanaceous S-RNases and the S-like RNases. The findings suggested that self-incompatibility mechanisms in Rosaceae and Solanaceae are similar but arose independently in the course of evolution. 相似文献