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991.
Takeshi Hanagiri Ichiro Yoshino Mitsuhiro Takenoyama Tomoko So Hiroshi Fujie Satoru Imabayashi Ryozo Eifuku Takashi Yoshimatsu Toshihiro Osaki Ryoichi Nakanishi Yuji Ichiyoshi Akira Nagashima Kikuo Nomoto Kosei Yasumoto 《Cancer science》1998,89(2):192-198
Lung cancer-specific cytotoxic T lymphocytes (CTL) were induced by repeated stimulations of regional lymph node lymphocytes (RLNL) in lung cancer patients with either autologous or HLA-A-locus-matched tumor cells. To investigate the effect of interleukin-12 (IL-12), IL-12 was added during the stimulation of RLNL from HLA A24 / adenocarcinoma patients with either autologous tumor cells or HLA A24-positive adenocarcinoma cells (PC-9) in combination with, or instead of interleukin-2 (IL-2), and then the cytotoxic activity, cytokine production and populations of the lymphocyte subsets were examined. The addition of IL-12, or the substitution of IL-2 by IL-12 was found to enhance the cytotoxic activity and the cytokine production (IFN-γ, GM-CSF) of the CTL as compared with IL-2 alone. The cytotoxic activity and cytokine production were both partially inhibited by anti-MHC-class I monoclonal antibody. The CTL thus induced by IL-12 had a higher proportion of CD3+ /CD56+ cells than the CTL induced with IL-2 alone. The positively selected CD8+ /CD56– lymphocytes showed PC-9-specific cytotoxic activity, because the population did not show any cytotoxicity to K562 or A549 (HLA-A26/A30). However, the CD3+ /CD56+ lymphocytes were cytotoxic to both PC-9 and K562. In conclusion, IL-12 is considered to be a useful cytokine for both the induction of lung-cancer specific CTL and the augmentation of non-MHC-restricted cytotoxicity against tumor cells, and may be applicable for adoptive immunotherapy using CTL. 相似文献
992.
A case of transient splenic accumulation of the bone-seeking agent Tc-99m HMDP is reported. This effect was caused by transient megaloblastic anemia induced by 5-fluorouracil chemotherapy. The extent of splenic uptake reflected the development and severity of megaloblastic anemia. The mechanism of splenic accumulation is thought to be similar to transient iron deposition in the spleen by megaloblastic anemia. 相似文献
993.
994.
Takahashi A Ohnishi K Tsuji K Matsumoto H Aoki H Wang X Tamamoto T Yukawa O Furusawa Y Ejima Y Tachibana A Ohnishi T 《International journal of radiation biology》2000,76(3):335-341
PURPOSE: There have been no reports about the effects of heavy-ion beams on the expression of the WAF1 gene, although ionizing radiation such as y-rays and X-rays is well known to induce WAF1 (p21/CIP1/sdi1) gene expression in a p53-dependent manner. In the present study, it was examined whether WAF1 accumulation was induced after carbon-ion (C-) beam or alpha-particle irradiation in four glioblastoma cell lines. MATERIALS AND METHODS: A colony assay for radiosensitivity and Western blot analysis of WAF1 were applied to two human glioblastoma cell lines, A-172 bearing wild-type p53 (wtp53) and T98G bearing mutated p53 (mp53). A-172/neo and A-172/mp53 were transfected with a control vector (containing only a neo selection marker) and a mp53 expression vector respectively. RESULTS: The amount of WAF1 increased markedly after X-ray irradiation in A-172 and A-172/neo cells but not in T98G and A-172/mp53 cells. The level of WAF1 reached a plateau at 3-10 h after X-ray irradiation at 5 Gy in A-172 and A-172/neo cells. Likewise, the levels of WAF1 in A-172 and A-172/neo cells reached a plateau at 3-10 h and 6-24 h after C-beam (3.0 Gy) and alpha-particle (4.5 Gy) irradiation respectively. The amount of WAF1 increased markedly in a dose-dependent manner 10 h after X-ray, C-beam or alpha-particle irradiation in A-172 and A-172/neo cells but not in T98G or A-172/mp53 cells. In addition, cell survival assay showed that these cell lines were most sensitive to C-beams, less sensitive to alpha-particles and least sensitive to X-rays at 10% survival. There was no difference in sensitivity among these cell lines against C-beam and alpha-particle irradiation whereas wtp53 cells (A-172 and A-172/neo) were more sensitive to X-rays than mp53 cells (A-172/mp53 and T98G). CONCLUSIONS: These results indicate that C-beams and alpha-particles induce p53-dependent WAF1 accumulation as well as is the case with X-rays, suggesting that WAF1 protein accumulation may not contribute to cell killing. 相似文献
995.
996.
Visual inspection with acetic acid for cervical cancer screening outside of low-resource settings. 总被引:2,自引:0,他引:2
Jose Jeronimo Orlando Morales Jorge Horna José Pariona Javier Manrique Jorge Rubi?os Rina Takahashi 《Pan American journal of public health》2005,17(1):1-5
OBJECTIVES: To assess visual inspection with acetic acid (VIA) as a screening tool for use in a well-equipped health center in Peru, to evaluate VIA as an alternative or adjunct to the Papanicolaou (Pap) smear, and to determine if VIA can play a role in settings other than low-resource ones. METHODS: This was a prospective study of 1 921 asymptomatic women living in Lima, Peru, carried out in 1999 and 2000. The study was performed at a cancer center equipped with the latest-generation technology and highly trained oncologists. The women underwent a complete clinical evaluation, including a Pap smear and VIA. Participants with any positive test were referred for colposcopy and biopsy. RESULTS: More women tested positive by VIA than on the Pap smear (6.9% vs. 4.2%; P = 0.0001). There were 35 women with histologic cervical intraepithelial neoplasia grade 1 (CIN 1); of these, 15 were detected by Pap and 20 by VIA (P = 0.4). A diagnosis of CIN 2 or 3 (CIN 2-3) was confirmed in a total of 13 cases; Pap detected 5 of the cases and VIA 11 of the cases (P = 0.06). The positive predictive value for detection of CIN 2+ was 8.3% for VIA and 6.3% for Pap (P = 0.5). Most importantly, while only 2.3% of patients with a positive VIA were lost to follow-up before colposcopy, that was true for 26.3% of the women with a positive Pap smear (P < 0.0001). CONCLUSIONS: VIA is useful for detection of precursor lesions of cervical cancer not only in low-resource settings but also in well-equipped health centers and cancer centers. In these non-low-resource settings, VIA has a positive predictive value comparable to the conventional Pap smear, but it is more likely to achieve earlier diagnosis, follow-up, and treatment than cytology-based screening. 相似文献
997.
Asaka Takahashi Hiroki Matsuoka Keiichi Yamada Yasushi Uda 《Food and chemical toxicology》2005,43(4):521-528
3-Allyl-5-substituted 2-thiohydantoins (ATH-amino acids) derived from allyl isothiocyanate and amino acids can inhibit the mutagenicity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in the Salmonella assay. In this report, we studied possible mechanisms for the inhibition using rat liver S9 in assays for ethoxyresorufin O-deethylase (EROD), a marker activity for cytochrome P450 1A (CYP1A), which activates heterocyclic amines, and the Salmonella assays with the direct-acting mutagen 2-hydroxyamino-3-methylimidazo[4,5-f]quinoline (N-hydroxy-IQ). Quantitative analysis of ATH-amino acids and IQ during incubation with rat liver S9 fraction by HPLC showed that ATH-amino acids could act as S9-inhibitors, thereby inhibiting metabolic activation of IQ. Among the tested ATH-amino acids, ATH-Phe, ATH-Trp, ATH-Leu and ATH-Val showed a dose-dependent inhibition of EROD activity. ATH-Gly, ATH-Glu, and ATH-Asp behaved as blocking agents toward N-hydroxy-IQ, but exhibited no inhibition of EROD activity. 相似文献
998.
Otukonyong EE Okutani F Takahashi S Murata T Morioka N Kaba H Higuchi T 《Brain research》2000,887(1):70-79
The exact role of leptin in fasting has not been completely elucidated. To determine whether leptin can act in fasting to influence plasma estrogen levels and nitric oxide synthase reactivity in food regulating centers of the brain, we fasted female rats for 4 days and treated them i.p. with vehicle or 100 microg of recombinant mouse leptin as 1 ml on the 3rd and 4th day twice daily (10.00 and 17.00 h). Proestrus blood was collected at 10.00, 14.00, 18.00 and at 22.00 h, plasma obtained and assayed for estrogen (E2) and leptin levels. Verification of ovulation occurrence was by examining the oviduct for extruded ovum. The rat brains were removed and processed for nitric oxide synthase reactivity in the ventromedial hypothalamus (VMH) and arcuate nucleus (ARC) using NADPH-diaphorase histochemistry, a marker for neurons expressing NOS enzyme. Leptin effect on dependable variables such as food intake, water intake and body weight gain was also investigated. Four days fasting significantly decreased body weight, estrogen and postfast leptin levels, nitric oxide reactivity in the VMH and ARC nucleus and stopped ovulation in many (4 out of 5) rats fasted and given vehicle. Leptin treatment significantly increased plasma estrogen and postfast leptin levels, restored ovulation in many (4 out of 5) rats and increased nitric oxide reactivity in the VMH and ARC. Leptin significantly inhibited food intake, water intake and gain in body weight during recommenced feeding. These observations suggest that leptin could act in the pituitary-ovarian axis during fasting to improve reproductive function by partly stimulating estrogen secretion. 相似文献
999.
Nishioka H Mizoguchi A Nakanishi H Mandai K Takahashi K Kimura K Satoh-Moriya A Takai Y 《The Journal of comparative neurology》2000,424(2):297-306
We have recently found a novel cell-cell adhesion system at cadherin-based adherens junctions. This system consists of at least two components: nectin, an immunoglobulin-like cell adhesion molecule with Ca(2+)-independent homophilic binding activity, and l-afadin, an actin filament-binding protein that connects nectin to the actin cytoskeleton. In the present study, we investigated immunocytochemically the localization of l-afadin in the mouse hippocampus. At the light microscopic level, l-afadin immunoreactivity was demonstrated as flattened disks in the stratum lucidum of the CA3 area. By immunoelectron microscopy, signals for l-afadin were highly concentrated in a symmetrical manner at the puncta adhaerentia-like junctions between the mossy fiber terminals and the dendritic trunks of pyramidal cells. We furthermore immunostained the hippocampus with antibodies recognizing both l-afadin and s-afadin, a small splicing variant of l-afadin that is identical to AF-6. Immunoreactivity for l- and s-afadins was demonstrated not only as the flattened disks similar to that for l-afadin, but also as numerous fine dots widely distributed in all synaptic layers of the CA1 and CA3 areas. The latter finding may correspond with the recent report by Buchert et al. (1999, J. Cell. Biol. 144:361-371), who found that s-afadin (AF-6) and/or l-afadin was localized at the postsynaptic membranes of asymmetric synaptic junctions. Our present results indicate that l- and s-afadins are differentially distributed in the hippocampus and suggest that l-afadin localized at the puncta adhaerentia-like junctions in the mossy fiber terminals may regulate the structural and functional organization of these complex synaptic structures. 相似文献
1000.
Evaluation of syringomyelia with three-dimensional constructive interference in a steady state (CISS) sequence 总被引:1,自引:0,他引:1
Hirai T Korogi Y Shigematsu Y Sugahara T Takahashi M Ushio Y Uemura S 《Journal of magnetic resonance imaging : JMRI》2000,11(2):120-126
The purpose of this study was to evaluate a three-dimensional (3D) constructive interference in steady state (CISS) sequence in the assessment of syringomyelia. Eleven patients with syringomyelia were prospectively studied with magnetic resonance imaging. All patients underwent sagittal imaging with T1- and T2-weighted spin-echo (SE), and 3D-CISS sequences. The SE and 3D-CISS images, as well as multiplanar reconstruction (MPR) images of the 3D-CISS sequence, were analyzed with regard to image quality, degree of artifacts, visualization of the extent and internal structure of the syringomyelia, and contrast-to-noise ratio (CNR) of the fluid within the syringomyelia. Contrast between the spinal cord and cerebrospinal fluid (CSF), as well as delineation was significantly poorer for the T1-weighted SE sequence than for the 3D-CISS sequence (P < 0.01), while there was no significant difference between the T2-weighted SE sequence and the 3D-CISS sequence. Artifacts induced by CSF flow were significantly more for the T2-weighted SE sequence than for the 3D-CISS sequence (P < 0.01). Although the extent of syringomyelia was delineated equally among the three sequences in 9 of 11 patients, it was better for the 3D-CISS sequence than for the SE sequences in the remaining two. Septation and communication between the cavities were best detected by the 3D-CISS MPR images. The CNR of the 3D-CISS sequence was significantly higher than that of the SE sequence (P < 0.01). The 3D-CISS sequence demonstrates the extent and internal structures of syringomyelia better than conventional SE sequences and should be added to SE sequences in the evaluation of syringomyelia. 相似文献