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51.
Yasuna Kobayashi Ryoko Sakai Naomi Ohshiro Masayuki Ohbayashi Noriko Kohyama Toshinori Yamamoto 《Drug metabolism and disposition》2005,33(5):619-622
Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver. 相似文献
52.
Dendritic Cells Coinjected with Tumor Cells Treated with an Anticancer Drug to Induce Tumor Rejection 总被引:1,自引:0,他引:1
Naoya Inoue Seiji Yamasaki Kan Kondo Takatsugu Kan Katsuyoshi Furumoto Masayuki Imamura 《Surgery today》2003,33(4):269-276
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug
was added.
Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally
(i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of
CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally.
Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC
alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26
cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher
level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was
followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed.
Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through
the acquisition of tumor-associated antigens from apoptotic tumor cells.
Received: January 7, 2002 / Accepted: September 3, 2002
Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry
of Education, Culture, Sports, Science and Technology (No. 11671160).
Reprint requests to: S. Yamasaki 相似文献
53.
Songji Zhao Yuji Kuge Takafumi Mochizuki Toshiyuki Takahashi Kunihiro Nakada Masayuki Sato Toshiki Takei Nagara Tamaki 《Journal of nuclear medicine》2005,46(4):675-682
The biologic mechanisms involved in the intratumoral heterogeneous distribution of 18F-FDG have not been fully investigated. To clarify factors inducing heterogeneous 18F-FDG distribution, we determined the intratumoral distribution of 18F-FDG by autoradiography (ARG) and compared it with the regional expression levels of glucose transporters Glut-1 and Glut-3 and hexokinase-II (HK-II) in a rat model of malignant tumor. METHODS: Rats were inoculated with allogenic hepatoma cells (KDH-8) into the left calf muscle (n = 7). Tumor tissues were excised 1 h after the intravenous injection of 18F-FDG and sectioned to obtain 2 adjacent slices for ARG and histochemical studies. The regions of interest (ROIs) were placed on ARG images to cover mainly the central (CT) and peripheral (PT) regions of viable tumor tissues and necrotic/apoptotic (NA) regions. The radioactivity in each ROI was analyzed quantitatively using a computerized imaging analysis system. The expression levels of Glut-1, Glut-3, and HK-II were determined by immunostaining and semiquantitative evaluation. The hypoxia-inducible factor 1 (HIF-1) was also immunostained. RESULTS: ARG images showed that intratumoral 18F-FDG distribution was heterogeneous. The accumulation of 18F-FDG in the CT region was the highest, which was 1.6 and 2.3 times higher than those in the PT and NA regions, respectively (P < 0.001). The expression levels of Glut-1, Glut-3, and HK-II were markedly higher in the CT region (P < 0.001) compared with those in the PT region. The intratumoral distribution of 18F-FDG significantly correlated with the expression levels of Glut-1, Glut-3, and HK-II (r = 0.923, P < 0.001 for Glut-1; r = 0.829, P < 0.001 for Glut-3; and r = 0.764, P < 0.01 for HK-II). The positive staining of HIF-1 was observed in the CT region. CONCLUSION: These results demonstrate that intratumoral 18F-FDG distribution corresponds well to the expression levels of Glut-1, Glut-3, and HK-II. The elevated expression levels of Glut-1, Glut-3, and HK-II, induced by hypoxia (HIF-1), may be contributing factors to the higher 18F-FDG accumulation in the CT region. 相似文献
54.
Randomized trial of cyclophosphamide, doxorubicin, and vincristine versus cisplatin and etoposide versus alternation of these regimens in small-cell lung cancer. 总被引:21,自引:0,他引:21
M Fukuoka K Furuse N Saijo Y Nishiwaki H Ikegami T Tamura M Shimoyama K Suemasu 《Journal of the National Cancer Institute》1991,83(12):855-861
Between April 1985 and May 1988, we conducted a randomized study comparing two standard chemotherapy regimens with the same regimens given on an alternating basis in patients with small-cell lung cancer. The patients were randomly assigned to receive cyclophosphamide at a dose of 800 mg/m2 intravenously (IV) on day 1, doxorubicin at 50 mg/m2 IV on day 1, and vincristine at 1.4 mg/m2 IV on day 1 (CAV); cisplatin at 80 mg/m2 IV on day 1 and etoposide at 100 mg/m2 IV on days 1, 3, and 5 (PE); or CAV alternating with PE (CAV/PE). Each regimen was repeated every 3-4 weeks. Three hundred patients were entered in the study, and 288 of them were eligible for analysis (97 for CAV, 97 for PE, and 94 for CAV/PE). The response rates for PE (78%) and CAV/PE (76%) were significantly higher than the rate for CAV (55%), while the complete response rates were similar (14%, 16%, and 15%, respectively). Nine (23%) of 39 patients who failed to respond to the initial CAV regimen responded to PE when they were crossed over. In contrast, only one (8%) of 13 patients responded to CAV after failing to respond to the PE regimen, suggesting that these two regimens were partially non-cross-resistant. The response duration on CAV/PE was significantly longer than that with CAV (P = .004). The survival time with CAV/PE (11.8 months) was superior to that with CAV (9.9 months) (P = .027) or that with PE (9.9 months) (P = .056). In patients with limited disease, the survival in the alternating arm was significantly superior to the survival in the CAV arm (P = .014) or the survival in the PE arm (P = .023). The toxic effects were acceptable in all three chemotherapy regimens. These results favor the alternating chemotherapy over either standard chemotherapy, such as CAV and PE, although the differences are not dramatic. 相似文献
55.
Atsuhiko Chiba Tatsuo Akema Masayuki Iigo Yuta Nagami Fukuko Kimura Jun-ichi Toyoda 《Journal of neuroendocrinology》1998,10(2):79-84
It has been recently reported that acute immobilization stress almost completely suppresses the luteinizing hormone (LH) release induced by naloxone, a μ-opioid antagonist, in ovariectomized estrogen-primed rats. The present study examined the possible involvement of the pineal gland in the acute immobilization-related suppression of the naloxone-induced LH release. An intraventricular (ICV) injection of 15 μg naloxone produced an abrupt increase in circulating LH concentrations in non-stressed rats. The naloxone-induced LH release was completely eliminated when tested 60 min after the end of a 30 min session of acute immobilization. The same stress conditions did not affect LH-releasing hormone (LHRH)-induced LH release, suggesting that the stress-related suppression of the naloxone-induced LH release was a suprapituitary event. In chronically-pinealectomized rats, but not in sham-pinealectomized rats, naloxone injected 60 min after the end of the stress session evoked a significant increase in serum LH concentrations. However, naloxone injected ICV during the acute immobilization did not elicit LH release in either pinealectomized or sham-operated rats. Under non-stressed conditions, the LH secretory response to naloxone was similar in pinealectomized and sham-operated animals. The same stress (30 min immobilization) significantly increased pineal melatonin content as well as plasma melatonin concentrations in rats bearing intact pineal glands, indicating that stress actually affected the pineal function. These results provide evidence for a role of the pineal in the suppression of the LH response to naloxone after stress, but not during stress. 相似文献
56.
Kaoru Nagahori Jun Itakura Hiroyasu Miura Hidemitsu Sugai Masayuki Yamamoto Yoshiro Matsumoto Takao Ainota Yoshihiro Akahane 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(3):288-291
We report a metastatic pulmonary tumor resected by video-assisted thoracoscopic surgery. A 63-year-old female was found to
have four nodules of hepatocellular carcinoma (HCC) in January 1991; after non-surgical treatment, the tumors had become necrotic.
In June 1992, a new HCC nodule was found. After infusion chemotherapy, it became necrotic. In September 1993, a solitary lung
tumor, 2.4 cm in diameter, appeared at the periphery of the right lung. Because the tumor was considered to be a metastatic
HCC rather than a primary lung cancer, it was removed by thoracoscopic wedge resection. Although whether metastasectomy contributes
to prolongation of survival is still controversial, thoracoscopic pulmonary resection may be indicated for solitary peripheral
metastasis, if the primary HCC is well controlled by multidisciplinary treatment. 相似文献
57.
Nakanishi M Yabe S Tanaka N Ito Y Nakamura KT Kitade Y 《Molecular and biochemical parasitology》2005,143(2):146-151
S-adenosylhomocysteine hydrolase is a prospective target for developing new anti-malarial drugs. Inhibition of the hydrolase results in an anti-cellular effect due to the suppression of adenosylmethionine-dependent transmethylations. Based on the crystal structure of Plasmodium falciparum S-adenosylhomocysteine hydrolase which we have determined recently, we performed mutational analyses on P. falciparum and human enzymes. Cys59 and Ala84 of the parasite enzyme, and the equivalent residues on the human enzyme, Thr60 and Gln85, were examined. Mutations of Cys59 and Thr60 caused dramatic impact on inhibition by 2-fluoronoraristeromycin without significant effect both on its kinetic parameters and on inhibition constant against noraristeromycin. In addition, the impact was independent from the electronegativity of the side chain of the substituting residue. These results showed that steric hindrance between a functional group at the 2-position of an adenine nucleoside inhibitor and Thr60 of the human enzyme, not an electrostatic effect, contributed to inhibitor selectivity. 相似文献
58.
Tomimori Y Muto T Fukami H Saito K Horikawa C Tsuruoka N Saito M Sugiura N Yamashiro K Sumida M Kakutani S Fukuda Y 《Laboratory investigation; a journal of technical methods and pathology》2002,82(6):789-794
An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis. 相似文献
59.
Macrophage Accumulation, Division, Maturation and Digestive and Microbicidal Capacities in Tuberculous Lesions: I. Studies Involving their Incorporation of Tritiated Thymidine and their Content of Lysosomal Enzymes and Bacilli 总被引:5,自引:8,他引:5 下载免费PDF全文
Kiyoshi Shima Arthur M. Dannenberg Jr Masayuki Ando Saroj Chandrasekhar Judith A. Seluzicki Jacob I. Fabrikant 《The American journal of pathology》1972,67(1):159-180
Dermal and pulmonary tuberculous lesions were produced in rabbits with BCG, biopsied, incubated in vitro with tritiated thymidine (3HT) under hyperbaric oxygen, quickly frozen, sectioned in a cryostat, stained for the lysosomal enzyme β-galactosidase, autoradiographed, stained for acid-fast bacilli and counterstained with hematoxylin. As macrophages developed into epithelioid cells, they could still divide—ie, incorporate 3HT. However, once they became fully mature epithelioid cells that were 4-plus in β-galactosidase, they could not do so. Tuberclebacilli did not stimulate macrophage division. On the contrary, macrophages containing bacilli did not divide, except when the lesions began. During the development of tuberculous lesions, macrophages (including those rich in enzymes and those containing bacilli) died, forming caseous centers. Therefore, local cell division did not seem to be the main mechanism by which macrophages reduced their bacillary load. Such division seemed mainly to occur in young macrophages that had recently immigrated into the lesions from the bloodstream and had not yet ingested bacilli. 相似文献
60.
While tissue engineering has long been thought to possess enormous potential, conventional applications using biodegradable scaffolds have limited the field's progress, demonstrating a need for new methods. We have previously developed cell sheet engineering using temperature-responsive culture dishes in order to avoid traditional tissue engineering approaches, and their related shortcomings. Using temperature-responsive dishes, cultured cells can be harvested as intact sheets by simple temperature changes, thereby avoiding the use of proteolytic enzymes. Cell sheet engineering therefore allows for tissue regeneration by either direct transplantation of cell sheets to host tissues or the creation of three-dimensional structures via the layering of individual cell sheets. By avoiding the use of any additional materials such as carrier substrates or scaffolds, the complications associated with traditional tissue engineering approaches such as host inflammatory responses to implanted polymer materials, can be avoided. Cell sheet engineering thus presents several significant advantages and can overcome many of the problems that have previously restricted tissue engineering with biodegradable scaffolds. 相似文献