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Y Sakamoto M Fujita J Ota R Sugiyama T Sugimoto T Taguchi 《Nihon Geka Gakkai zasshi》1990,91(3):326-334
Enhancement of the antitumor effects of adriamycin (ADR) by concomitant use of degradable starch microspheres (DSM) and pharmacokinetics of ADR in combination with DSM was investigated. An intra-arterial chemotherapy model of the nude rats transplanted of human gastric cancer xenografts (H-154) in the hind-limbs was used for this study. Drug was administered through a catheter inserted into the carotid artery with the tip in the common iliac artery. In the pharmacological study, increase of regional uptake of ADR and decrease of systemic distribution of ADR were recognized in some degree. DSM 30 mg/kg, which caused temporary arrest of blood flow in the tumor, had an only weak effect on tumor growth. ADR 3 mg/kg mixed with DSM 30 mg/kg was more effective than ADR 3 mg/kg solution. Furthermore, mixture of ADR 2 mg/kg and DSM 30 mg/kg had a greater effect on tumor growth than ADR 2 mg/kg following DSM 30 mg/kg. It seems that embolization by DSM, retention of ADR in regional tissues and cytotoxic effect of ADR have contributed to such a strong effect of ADR mixed with DSM. 相似文献
23.
The effect of a continuous i.v. infusion of alpha-difluoromethylornithine (DFMO) on the polyamine metabolism of tumor and normal host tissue was determined. Non-tumor-bearing Fischer 344 rats or rats bearing a transplantable fibrosarcoma received continuous infusions of DFMO through a central venous catheter at three dose levels. Treatment with DFMO resulted in a time- and dose-dependent, cytostatic effect on the growth of the tumor. In fibrosarcoma-bearing rats the tumor putrescine levels were reduced after 6 and 12 days of DFMO treatment. Tumor spermidine levels were consistently reduced after 6 and 12 days of treatment with the reduction being dose dependent. The decrease in tumor ornithine decarboxylase activity was dose dependent. Erythrocyte putrescine levels were decreased in tumor- and non-tumor-bearing rats, suggesting that DFMO reduces the tumor contribution to the erythrocyte pool. Erythrocyte spermidine levels of fibrosarcoma- and non-tumor-bearing rats were elevated at the lower DFMO doses administered for 12 days but returned to normal as the dose was increased. Erythrocyte spermine levels were elevated in both groups of rats at all DFMO doses. Although normal host tissue weights were not affected by treatment with DFMO, the putrescine and spermidine levels of liver, spleen, and kidney and ornithine decarboxylase activity of the liver and kidney were decreased. These data demonstrate that i.v. DFMO has a cytostatic effect toward a rapidly growing fibrosarcoma associated with the depletion of both tumor putrescine and spermidine levels. 相似文献
24.
Ryozo Oishi Yoshinori Itoh Tamotsu Fukuda Yasunori Araki Kiyomi Saeki 《Journal of neural transmission (Vienna, Austria : 1996)》1988,73(1):65-69
Summary The size of the neuronal and non-neuronal histamine pools in the brain of three different strains of rats was measured by assuming that the -fluoromethylhistidine-induced maximal decrement of histamine represents the size of the neuronal pool. Although the total histamine levels in the brain showed a considerable interstrain variation, no significant interstrain difference was observed in the neuronal histamine level. These results suggest that the size of the neuronal histamine pool in the brain is relatively stable, whereas the size of the non-neuronal histamine pool is variable. 相似文献
25.
This paper describes the fundus appearance, visual function and electrophysiological findings in five cases of Kearns-Sayre syndrome. In three of them, retinopathy was not seen before the onset of this syndrome. The characteristic "salt and pepper retinopathy" progressed to peripapillary loss of the RPE and choriocapillaris over a period of some years. The ERG, normal in the beginning, became extinct in these cases. They were also at first subnormal for the scotopic as well as for the photopic activity. We distinguished five stages of ocular manifestations in Kearns-Sayre syndrome. Stage 0: The fundus appearance and the visual function are normal. Stage I: "Salt and pepper retinopathy" occurs in the entire retina but the visual function and the ERG are still normal. Stage II: Abnormal visual function and ERG occur with retinopathy. Stage III: A chorioretinal atrophy progresses around the disc and nasal retina and the ERG becomes extinct. Stage IV: The retinopathy demonstrates the appearance of choroidal sclerosis. 相似文献
26.
Suzuki Hisamitsu; Ota Kazuo; Ohno Ryuzo; Masaoka Toru; Shibata Hirotoshi; Kimura Ikuro; Amaki Ichita; Miura Yasusada; Uzuka Yoshiro; Kawato Masafumi; Shirakawa Shigeru; Hirota Yutaka; Maekawa Tadashi; lmai Kuniyuki; Takaku Fumimaro; Shimoyama Masanori; Kitahara Takeshi; Oguro Masao; Kozuru Mitsuo; Kawagoe Hiroya; Nakamura Toru; Yamada Kazumasa 《Japanese journal of clinical oncology》1989,19(4):338-347
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 19711975 to 62.3%during 19811985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 19711975and 69.7% during 19811985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 3740 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe. 相似文献
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28.
Metal ions induce bone-resorbing cytokine production through the redox pathway in synoviocytes and bone marrow macrophages 总被引:6,自引:0,他引:6
Niki Y Matsumoto H Suda Y Otani T Fujikawa K Toyama Y Hisamori N Nozue A 《Biomaterials》2003,24(8):1447-1457
To evaluate the biological reactions to metal ions potentially released from prosthetic implants, we examined the ability of metal ions to produce bone-resorbing cytokines and the underlying mechanism using synoviocytes and bone marrow (BM) macrophages. The cells were incubated with NiCl(2), CoCl(2), CrCl(3) or Fe(2)(SO(4))(3) at optimal concentrations, which are detectable in joint fluid following total joint arthroplasty. The production of interleukin-1beta, interleukin-6 and tumor necrosis factor-alpha were enhanced by all metal ions tested as determined by enzyme-linked immunosorbent assay. From the results of electrophoresis mobility shift assay, all metal ions enhanced the DNA-binding activity of nuclear factor kappaB (NF-kappaB), and p50-p65 heterodimers and p50 homodimers were the major subunits. These effects of the metal ions were considerably blocked by pyrrolidine dithiocarbamate (PDTC) known as a radical scavenger. An electron spin resonance study clearly demonstrated the ability of metal ions to generate activated oxygen species (AOS), especially hydroxyl radicals (*OH), which accounts for PDTC-blockade of metal ion-induced NF-kappaB activation and subsequent cytokine production. Taken together, our data raised the possibility that small amounts of metal ions released from prosthetic implants activate synoviocytes and BM macrophages through the AOS-mediated process (i.e. the redox pathway), and contribute to the initiation of osteolysis at the bone-implant interface. 相似文献
29.
Tsuneyuki Sato Yoshiko Takahashi Makiko Seno Hiroyuki Nakamura Hitoshi Tanaka Tadatoshi Ota 《Macromolecular chemistry and physics.》1991,192(12):2909-2914
Polymerization of dialkyl itaconates with dimethyl azoisobutyrate ( 5 ) was studied in benzene at 50°C by means of electron spin resonance (ESR). The monomers used are dimethyl ( 1 ), diethyl ( 2 ), dibutyl ( 3 ) and di-2-ethylhexyl ( 4 ) itaconates. All the polymerization systems involve ESR-observable propagating polymer radicals under the actual polymerization conditions. The polymerization rate (Rp) and degree of polymerization of the resulting polymer increase in going from shorter to longer alkyl groups. The ESR-determined rate constants of propagation (kp) and termination (kt) decrease as the alkyl chain becomes longer. kp of 1 is 3,3 times higher than that of 4 , while kt of 1 is 590 times higher than that of 4 . Thus, the steric effect due to the alkyl group suppresses much more termination than propagation, leading to the fact that Rp increases as the alkyl group becomes larger. 相似文献
30.