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51.
Y. Tsutsumi T. Kihira S. Tsunoda T. Kanamori S. Nakagawa T. Mayumi 《British journal of cancer》1995,71(5):963-968
This study was conducted to increase the anti-tumour potency and reduce the toxic side-effects of tumour necrosis factor alpha (TNF-alpha). Natural human TNF-alpha was chemically conjugated with monomethoxy polyethylene glycol (PEG) using succinimidyl coupling of lysine amino groups of TNF-alpha. The number-average molecular weight of PEG-modified TNF-alpha (PEG-TNF-alpha) increased with an increase in the reaction time and the initial molar ratio of PEG relative to TNF-alpha. The resulting modified TNF-alpha was separated into fractions of various molecular weights. The specific activity of separated PEG-TNF-alpha s relative to that of native TNF-alpha gradually decreased with an increase in the degree of PEG modification, but the plasma half-life was drastically increased with the increase in molecular weight of modified TNF-alpha. PEG-TNF-alpha s, in which 29% and 56% of lysine residues were coupled to PEG, had anti-tumour activity approximately 4 and 100 times greater than unmodified TNF-alpha in the murine Meth-A fibrosarcoma model. Extensive PEG modification did not increase its in vivo activity. A high dose of unmodified TNF-alpha induced toxic side-effects, but these were not observed with the modified TNF-alpha s. Optimal PEG modification of TNF-alpha markedly increased its bioavailability and may facilitate its potential anti-tumour therapeutic use. 相似文献
52.
Eiji Nakagawa Hideo Yamanouchi Norio Sakuragawa Sachio Takashima 《Brain & development》1994,16(6):488-490
We report a case of acute cerebellar ataxia (ACA) with discrete paleocerebellar clinical symptoms who underwent serial cranial magnetic resonance images not only with conventional spin echo sequences but also fluid attenuated inversion recovery (FLAIR) sequences. The images with the latter sequences demonstrated more conspicuously the high signal intensity lesions in the superior cerebellar vermis and cerebellar peduncle than those with the former sequences. In the convalescent phase, the lesions became markedly atrophic. Thus, the causative lesions for ACA were demonstrated on MRI, and FLAIR provided clear images of the lesion in the vermis. 相似文献
53.
Ikuo Konishi M.D. Kanako Nanbu M.D. Masaki Mandai M.D. Yuko Tsuruta M.D. Nobuhiko Kataoka M.D. Yasushi Nagata M.D. Takahide Mori M.D. 《Gynecologic oncology》1998,70(3):365-371
Objective.To identify the clinicopathological and chemoresistant factors predicting the response to neoadjuvant chemotherapy and the patient prognosis in high-risk cervical carcinomas.Methods.We retrospectively reviewed 47 patients with locally advanced or bulky cervical carcinoma treated with two courses of intraarterial infusion of cisplatin, doxorubicin, mitomycin C, and 5-fluorouracil (5-FU), followed by radical hysterectomy at our hospital between 1988 and 1995. Expressions of the chemoresistance-related proteins, such as P-glycoprotein, glutathioneS-transferase π (GST-π), and proliferating cell nuclear antigen (PCNA) in the tumor cells, were examined by immunohistochemistry using pretreatment biopsy specimens. These results were compared with the chemotherapeutic response, which was evaluated by magnetic resonance imaging (MRI) and histopathology. Outcome of the patients was also studied.Results.Chemotherapeutic effect of either complete (CR) or partial (PR) response on MRI was obtained in 36 of the 47 (86%) patients. Poor response to chemotherapy was significantly correlated with P-glycoprotein expression (P< 0.005) and low PCNA labeling (P< 0.05), but not GST-π expression in the tumor cells. Independent prognostic factors for patient survival were parametrial involvement and lymph node metastasis. Neither the expression of GST-π nor PCNA was correlated with the patient survival.Conclusion.Assessment of the expression of P-glycoprotein and PCNA is potentially useful for the prediction of tumor response to neoadjuvant chemotherapy for cervical carcinomas. 相似文献
54.
55.
S Kitagawa M Nakagawa T Yamada Y Mori H Simizu S Rin H Kurumaya 《Nihon Geka Gakkai zasshi》1990,91(8):1001-1010
Xanthogranulomatous cholecystitis (XGC) is an uncommon lesion which may form a tumor-like mass in inflamed gallbladders. In a review of 44 cases there were 40 associated with gallstones which had been incarcerated in the neck of the gallbladder, 10 with past histories of abdominal surgeries, 15 with diabetes mellitus, three with carcinomas in the neck of the gallbladder and four with carcinomas in the other organs. Radiologically the differential diagnosis of gallbladder cancer and XGC was difficult in several cases. Thirty five cases of XGC have been diagnosed as chronic cholecystitis and 7 have been mistaken for feature of XGC in the contrast enhancement CT that is, detection of an intramural low density mass with continuously enhanced internal membraneous layer of the gallbladder wall. In view of the clinico-pathological findings of XGC, the lesions appear to result from intramural extravasation of bile and subsequent xanthogranulomatous reaction under obstructive conditions in the neck of the gallbladder. We conclude that XGC is not an uncommon special type of cholecystitis but an accompanied lesion sometimes seen in a kind of cholecystitis. 相似文献
56.
57.
Ida-Marie Stender Takafumi Etoh Tetsuya Tsuchida Hidemi Nakagawa H. Randolph Byers Genji Imokawa Yasumasa Ishibashi 《The Journal of dermatology》1993,20(10):611-617
The ability of the human amelanotic melanoma cell line MM-RU to produce experimental metastases and to grow tumors at subcutaneous inoculation sites in 4-week-old nude mice was examined. After i.v. inoculation of 106 cells, all injected mice (n=21) developed consistent numbers of metastatic pulmonary colonies within 32 days. The coefficients of variation for the number of colonies were between 17%–23% in three independent experiments. Survival time after i.v. inoculation was 63 ± 7 days (mean ± SD) (n=20). Within 20 days, subcutaneous inoculation of 5 × 106 cells resulted in tumor growths of 13 ± 3 mm (mean ± SD) at the inoculation sites in all nude mice (n=12). The MM-RU cell line seems to be a simple, fast vehicle for testing the effect of melanoma growth modulators on experimental pulmonary metastases as well as on subcutaneously growing melanoma. 相似文献
58.
Development of new immunoradiometric assay for CA 125 antigen using two monoclonal antibodies produced by immunizing lung cancer cells 总被引:4,自引:0,他引:4
Mihoko Kunimatsu Keigo Endo Tetsuo Nakashima Toshikazu Awaji Tsuneo Saga Yuji Watanabe Yasutaka Kawamura Hitoya Ohta Mitsuru Koizumi Harumi Sakahara Junji Konishi Shingo Fujii Takahide Mori Kanji Torizuka Yoichiro Matsuoka Tsuyoshi Nakagawa Nobuo Yamaguchi 《Annals of nuclear medicine》1988,2(2):73-79
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen. 相似文献
59.
A single oral administration of orthophenylphenol (OPP, 1400 mg/kg; about half the LD50) to male Fischer 344 rats produced an elevation of serum transaminase activity 24 h later. Pretreatment with l-buthionine-S,R-sulfoximine (BSO, 900 mg/kg) in the OPP-treated rats potentiated the hepatic and renal damage which was accompanied by necrosis. Six hours after the administration of OPP (700 or 1400 mg/kg), hepatic and renal glutathione (GSH) levels decreased with increasing dosage. Hepatic GSH depletion with OPP was enhanced with BSO pretreatment and the recovery of GSH in both organs was slow in the high-dose OPP group. These results suggest that hepatic and renal damage is associated with a serious and prolonged GSH depletion. When either phenyl-p-benzoquinone (PBQ) or phenylhydroquinone (PHQ), which are intermediates of OPP, was administered orally to rats at 700 or 1400 mg/kg, the mortality with the high dose of PBQ was 75% at 24 h. The serum transaminase activity and UN level increased with the low dose of PBQ, accompanied by necrotic hepatocytes. The toxic effects of PHQ on kidney or liver were less than those on PBQ. These observations suggest that the liver and kidney may be target organs for toxic actions of a large dose of OPP and its intermediate, PBQ.Part of this work was presented at IInd International ISSX Meeting Xenobiotic Metabolism and Disposition, May 16–20, 1988, Kobe, Japan 相似文献
60.
We investigated the relative effects of 0.5, 1.0, 1.5, 2.0 MAC halothane and enflurane, and concurrent noxious stimulus on hepatic blood flow and oxygen consumption in 14 mongrel dogs randomly divided into groups of seven each. Hepatic arterial and portal venous blood flow (HABF and PVBF, respectively) were measured continuously using ultrasonic transit time flow meter. Mean arterial blood pressure (MAP), cardiac index (CI), hepatic oxygen supply, and hepatic oxygen consumption (H
O
2) were measured. Halothane significantly deceased HABF, but not PVBF in a dose dependent manner. Enflurane did not affect HABF and PVBF significantly. MAP and CI decreased in both groups, with halothane producing more marked decreases than enflurane. H
O
2 did not change with enflurane, but did with halothane, producing significant differences, with halothane being greater at 1.5, 2.0 MAC. A noxious stimulus only caused minor change in blood flow. The results suggest that liver blood flow and oxygen consumption are affected differently by halothane and enflurane and that halothane has a stronger tendency to cause an imbalance between liver oxygen supply and consumption than dose enflurane.(Masaki E, Yasuda N, Tanifuji Y et al.: Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs. J Anesth 3: 118–122, 1989) 相似文献