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991.
Cyclooxygenase-2 inhibitor and interferon-beta synergistically induce apoptosis in human hepatoma cells in vitro and in vivo 总被引:3,自引:0,他引:3
Nakamoto N Higuchi H Kanamori H Kurita S Tada S Takaishi H Toda K Yamada T Kumagai N Saito H Hibi T 《International journal of oncology》2006,29(3):625-635
Recent clinical trials have shown that interferon (IFN) is effective for chemoprevention against hepatocellular carcinoma (HCC). However, it remains controversial as to whether IFN exerts direct cytotoxicity against HCC. Cyclooxygenase (COX)-2 also plays a role in hepatocarcinogenesis and may mediate resistance to apoptosis in HCC. Therefore, we aimed to elucidate the combined effect of COX-2 inhibitor, NS-398, and IFN on in vitro growth suppression of HCC using 3 hepatoma cell lines (HepG2, PLC/PRF/5, and Huh7) and in vivo nude mouse xenotransplantation model using Huh7 cells. Only minimal growth inhibition was observed after treatment with IFN-beta alone in the 3 hepatoma cell lines. In contrast, treatment with NS-398 and IFN-beta synergistically inhibited cell proliferation in dose- and time-dependent manner. Apoptosis was identified by 4',6-diamidino-2-phenylindole dihydrochloride and fluorescent staining. IFN-beta up-regulated the expression of TRAIL, while NS-398 increased the expression of TRAIL receptors (especially of death receptor 5). Subsequently, activation of caspase-8 and caspase-3 was observed following the treatment with NS-398 and IFN-beta. Blockade of TRAIL with a specific antibody attenuated this apoptosis. Furthermore, we found that IFN-beta up-regulated COX-2 expression in Huh7 cells, and NS-398 might suppress the up-regulated COX-2 activity downstream of IFN signaling. In vivo experiment showed the combined regimen with NS-398 and IFN-beta reduced the growth of xenotransplated HCCs in nude mice. In conclusion, NS-398 is sufficient to overcome IFN resistance in hepatoma cells through the TRAIL/TRAIL receptor pathway, therefore, the combination would appear to be a new therapeutic regimen for HCC. 相似文献
992.
Miyamoto S Kohno H Suzuki R Sugie S Murakami A Ohigashi H Tanaka T 《Oncology reports》2006,15(5):1169-1173
The modifying effects of dietary feeding with chrysin (5,7-dihydroxyflavone) on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) were investigated in male F344 rats. We also assessed the effect of chrysin on mitosis and apoptosis in 'normal appearing' crypts. To induce ACF, rats were given two weekly subcutaneous injections of AOM (20 mg/kg body weight). They also received an experimental diet containing chrysin (0.001 or 0.01%) for 4 weeks, starting 1 week before the first dose of AOM. AOM exposure produced a substantial number of ACF (73+/-13/rat) at the end of the study (week 4). Dietary administration of chrysin caused significant reduction in the frequency of ACF: 0.001% chrysin, 37+/-17/rat (49% reduction, P<0.001); and 0.01% chrysin, 40+/-10/rat (45% reduction, P<0.001). In addition, chrysin administration significantly reduced the mitotic index and significantly increased the apoptotic index in 'normal appearing' crypts. These findings might suggest a possible chemopreventive activity of chrysin in the early step of colon tumorigenesis through modulation of cryptal cell proliferation activity and apoptosis. 相似文献
993.
Kondo K Tanaka T Hirota Y Kawamura H Miura H Sugioka Y Inoue H Kurosaka M Yamashita T Shirata K Iwamoto Y 《Journal of epidemiology / Japan Epidemiological Association》2006,16(1):21-29
BACKGROUND: Osteoarthritis (OA) of the knee is a common form of arthritis, and affects quality of life. We investigated factors associated with functional limitation in stair climbing among female Japanese patients with knee OA. As weight is a known risk factor for knee OA, we focused on body weight at 40 years of age, and examined the association with present weight, past weight, and weight change. METHODS: Subjects were 360 Japanese women aged 40-92 years who were newly diagnosed with knee OA at 3 university hospitals over a 1-year period. Factors associated with the severity of functional limitation in stair climbing were assessed by calculating odds ratios (OR) using the proportional odds model in logistic regression. RESULTS: Weight at diagnosis showed a positive association with severe functional limitation in stair climbing; however, a negative association was observed for weight change since age 40. Further analysis indicated that the association with weight at age 40 (highest vs. lowest quartile, OR=2.84, 95% confidence interval: 1.03-7.83, trend p=0.071) is stronger than weight at diagnosis. Other significant characteristics were age (70+ vs. 40-59 years, OR=7.37), previous knee pain and/or swelling 12 years or more before diagnosis (OR=2.67), and physical work (OR=1.94). In addition, higher parity was found to be a negatively associated factor (for tripara or more, OR=0.41). CONCLUSIONS: This study identified factors, such as heavy weight at age 40 and physical labor, which are potentially useful for preventing severe functional limitation for female knee OA patients. In addition, higher parity was associated with milder stair climbing limitation. 相似文献
994.
Kaneki M Hosoi T Ouchi Y Orimo H 《Nutrition (Burbank, Los Angeles County, Calif.)》2006,22(7-8):845-852
Vitamin K is a nutrient that was originally identified as an essential factor for blood coagulation. Recently, vitamin K has emerged as a potential protector against osteoporosis, atherosclerosis, and hepatocarcinoma. Accumulated evidence indicates that subclinical non-hemostatic vitamin K deficiency in extrahepatic tissues, particularly in bone and possibly in vasculature, exists widely in the otherwise healthy adult population. Vitamins K1 and K2 have been shown to exert protective effects against osteoporosis, although it is important that the beneficial effects will be further confirmed by large-scale, randomized, clinical trials. Increasing evidence implicates a role for vitamin K in calcification of arteries and atherogenesis. Moreover, the therapeutic potential of vitamin K2 as an antihepatoma drug has recently been highlighted. Most of the new biological functions of vitamin K in bone, vasculature, and hepatoma cells are considered attributable to promotion of gamma-carboxylation of glutamic acid residues in vitamin K-dependent proteins, which is shared by vitamins K1 and K2. In contrast, vitamin K2-specific, gamma-carboxylation-unrelated functions have also been demonstrated. Thus, biological differences between vitamins K1 and K2 and potential involvement of gamma-carboxylation-independent actions in the new roles of vitamin K remain open issues. Molecular bases of coagulation-unrelated pleiotropic actions of vitamin K and its implications in human health deserve further investigations. 相似文献
995.
Herb-drug interaction has attracted attention as medicinal topics recently. However, the drug information is sometimes confusing. Previous in vitro studies revealed that schisandra fruit had strong inhibitory effect on CYP3A4 and claimed the possibilities of its herb-drug interaction. In the present study, we evaluated the inhibitory effects of schisandra fruit and shoseiryuto, an herbal formula in Japanese traditional kampo medicine containing eight herbal medicines including schisandra fruit, on rat CYP3A activity in vitro, and the effect of shoseiryuto on pharmacokinetics of nifedipine in rats, in comparison with those of grapefruit juice, a well-characterized natural CYP3A inhibitor. Shoseiryuto and its herbal constituents, schisandra fruit, ephedra herb and cinnamon bark exhibited in vitro inhibitory effect of CYP3A. Although shoseiryuto inhibited rat CYP3A activity in vitro with a degree comparable to grapefruit juice, shoseiryuto did not significantly affect a plasma concentration profile of nifedipine in rats as grapefruit juice did. These results indicate that in vivo experiments using the extract of herbal medicine prepared with the same dosage form as patients take are necessary to provide proper information about herb-drug interaction. 相似文献
996.
997.
A selective inhibitor of Na+/Ca2+ exchanger, SEA0400, preserves cardiac function and high-energy phosphates against ischemia/reperfusion injury 总被引:2,自引:0,他引:2
Feng NC Satoh H Urushida T Katoh H Terada H Watanabe Y Hayashi H 《Journal of cardiovascular pharmacology》2006,47(2):263-270
The Ca2+ overload by Ca2+ influx via Na+/Ca2+ exchanger (NCX) is a critical mechanism in myocardial ischemia/reperfusion injury. We investigated protective effects of a novel selective inhibitor of NCX, SEA0400, on cardiac function and energy metabolism during ischemia and reperfusion. Langendorff-perfused rat hearts were exposed to 35 minutes global ischemia and 40 minutes reperfusion. Using 31P nuclear magnetic resonance spectroscopy, cardiac phosphocreatine (PCr), ATP, and pHi were monitored. SEA0400 did not change the basic cardiac function, but improved the recovery of left ventricular developed pressure (LVDP) after reperfusion (27.6 +/- 4.9 mm Hg in control, 101.2 +/- 19.3 mm Hg in 0.1 microM, and 115.5 +/- 13.3 mm Hg in 1 microM SEA0400, means +/- SE, n = 6, P < 0.05). SEA0400 reduced left ventricular end-diastolic pressure and increased coronary flow after reperfusion. SEA0400 improved the recoveries of cardiac phosphocreatine and ATP after reperfusion, but did not affect pHi. There were significant linear correlations between left ventricular developed pressure and cardiac phosphocreatine (r = 0.79, P < 0.05), and left ventricular developed pressure and ATP (r = 0.80, P < 0.05). However, SEA0400 increased the incidence and duration of reperfusion ventricular arrhythmias. SEA0400 added only after reperfusion also improved both the contractile function and energy metabolism. It is concluded that the selective inhibition of NCX may be effective to preserve high-energy phosphates and to improve cardiac function after reperfusion, but may not be able to prevent fatal arrhythmias. 相似文献
998.
Chikara Ogura Kazuaki Majima Kazuyoshi Nakasawa Ikan Nakamura Yoichi Umezawa Hajime Ueda 《European journal of clinical pharmacology》1978,13(6):413-418
Summary A new method, 24-hour polygraphy (EEG, EMG, and EOG), was applied not only to investigate the influence of hypnotics on night sleep, but to examine the precise influence on sleep-wake-fulness rhythm the day following administration. The hypnotics used were flurazepam 15 mg and nitrazepam 5 mg. The subjects were healthy volunteers, 5 men and 4 women, aged 20–50 years. The polygraphic record was made three times for each subject. Flurazepam prolonged sleep time (%) significantly (p<0.05), shortened sleep latency (p<0.05), decreased waking period (p<0.05), and increased the percentage of Stage 2 sleep (p<0.1) in comparison to nitrazepam. Flurazepam 15 mg appears to be a better hypnotic than nitrazepam 5 mg, but caution is required in its use because of a greater residual sedative effect on the following day. Some nondrug factors affecting sleep and a method for detecting the residual effect of hypnotics are discussed. 相似文献
999.
This report consists of two cases who died after a neurological disorder of the central nervous system consistent with Behcet's disease clinically and pathologically. Post-mortem examination of the central nervous system revealed mild diffuse meningo- encephalitis with multiple foci of softening, demyelination and glial cell accumulation in the pons, midbrain, cerebral peduncle and internal capsule. The significance of these morphological findings has been discussed from an etiological viewpoint of Neuro-Behcet's syndrome. 相似文献
1000.
A case of diprosopus, a very rare malformation belonging to dupli-citas, of a female newborn is reported. This diprosopus monauchenos tetrophthalmus triotus dioris was delivered from a 33 years old multipara. Autopsy revealed duplication of cerebral hemispheres, 1st, 2nd and 3rd cranial nerves, hypophysis, intracranial internal carotid arteries, basilar artery and tip of tongue. This diprosopus had also congenital cardiac and great vessel anomalies consisting of double outlet right ventricle without pulmonary stenosis, coarctation of aorta (infantile type), ventricular septal defect, patent ductus arteriosus, patent foramen ovale and thick right ventricular wall. Except for mesenterium commune, the organs in the chest and abdomen, and the extremities were normal in position, shape and number. ACTA PATH. JAP. 20: 239–249, 1970. 相似文献