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991.
Dendritic cells (DCs) initiate and regulate immune responses. Numerous studies in mice showed that tumor antigens-loaded DCs are able to induce therapeutic and protective anti-tumor immunity. The immunogenicity of antigens delivered on DCs has now been demonstrated in cancer patients and some clinical responses without any significant toxicity have been observed. Nevertheless, many parameters of DC vaccination need to be established including: (1) the type of DCs, their maturation stage and stimuli; (2) the quality and the breadth of induced immune responses; (3) host-related factors, such as the extent of metastatic disease and myeloablation; and (4) efficacy as measured by the clinical outcome. 相似文献
992.
Romanenko A Morimura K Wanibuchi H Wei M Zaparin W Vinnichenko W Kinoshita A Vozianov A Fukushima S 《Cancer science》2003,94(4):328-333
The incidence of urinary bladder cancer in the Ukraine increased from 26.2 to 43.3 per 100 000 population between 1986 and 2001 after the Chernobyl accident. The present study was conducted to evaluate the development of radiation-dependent lesions in the urinary bladders of people living in cesium 137 (137 Cs) radio-contaminated areas of the Ukraine. Bladder urothelial biopsies from 159 male and 5 female patients were subjected to histological examination and immunohistochemical study of p38 mitogen-acti-vated protein kinase (MAPK), as well as the p50 and p65 subunits of nuclear factor kappa B (NF- k B). A pattern of chronic proliferative atypical cystitis accompanied with large areas of sclerosis of connective tissue in the lamina propria was commonly observed in all cases. Interestingly, these lesions were associated with a dramatic increase in the incidences of dysplasia/carcinoma in situ , and, moreover, small urothelial carcinomas were incidentally detected. We defined the overall condition as "Chernobyl cystitis.'Greatly elevated levels of p38, p65 and p50 expression in the urothelium were evident and the patients showed increased 137 Cs in urine. The data support conclusions from our previous studies of a critical role for increased oxidative stress in generation of urinary bladder urothelial lesions in individuals chronically exposed to low-dose 137 Cs radiation. Alterations in the p38 MARK cascade and accumulation of NF- k B subunits could be crucial early molecular events in the pathogenesis of Chernobyl cystitis. (Cancer Sci 2003; 94: 328–333) 相似文献
993.
Mitsuhashi M Wanibuchi H Morimura K Doi K Wei M Wada S Nakatani T Fukushima S 《Cancer science》2003,94(12):1052-1058
Metallothionein (MT) is expressed in various types of human tumors, including transitional cell carcinomas of the urinary bladder, but its biological significance remains unclear. In the present study, the role of MT in urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) treatment was investigated using C57BL/6 mice. One hundred 5-week-old male C57BL/6 mice were divided into two groups, which were given drinking water with or without 0.05% BBN throughout the experimental period. Subgroups of ten animals from each group were sacrificed at weeks 5, 10, 15, 20 and 25, and urinary bladder samples were examined immunohistochemically for MT, proliferating cell nuclear antigen (PCNA) and apoptosis. MT was found to be abundant in normal-looking mucosa, but decreased with progression from precancerous lesions to invasive carcinoma in the urinary bladder obtained from BBN-treated mice. Lesions could be divided into MT-positive and negative. There was a tendency for greater MT expression in PCNA-positive lesions, while apoptosis was rather associated with MT-negativity. These data suggest that the overexpression of MT may play a role in mouse urinary bladder carcinogenesis. 相似文献
994.
Hypothesis
The principle aim of the current study is to test the hypothesis that the long-term use of highly purified EPA (eicosapentaenoic acid: 1800 mg/day), in addition to HMG-CoA reductase inhibitor, is effective in preventing cardiovascular events in Japanese patients with hypercholesterolemia.Background
Epidemiological and clinical evidence suggest that intake of long-chain polyunsaturated n-3 fatty acids (PUFAs), which are abundant in fish, might have a significant role in the prevention of coronary artery disease, as marine PUFAs have multiple biological functions through lipid-dependent and lipid-independent mechanisms.Methods
The Japan EPA Lipid Intervention Study (JELIS) is a prospective, randomized, open-label, blinded end point trial including both primary and secondary prevention strata, with a maximum follow-up of 5 years. Its main purpose is to examine the clinical effectiveness of EPA oil given as an additional treatment to patients taking HMG-CoA reductase inhibitors for hypercholesterolemia.A primary end point is major coronary events: sudden cardiac death, fatal and nonfatal myocardial infarction, and unstable angina pectoris including hospitalization for documented ischemic episodes, and events of angioplasty/stenting or coronary artery bypass grafting. Secondary end points include all-cause mortality, stroke, peripheral artery disease, and cancer.Baseline study composition comprises 15,000 participants (4204 men and 10,796 women) in the primary prevention stratum and 3645 (1656 men and 1989 women) in the secondary stratum.The minimum age is 40 years for men, women are required to be postmenopausal, and all patients must be ≤75 years of age. The mean age of participants is 61 years, and 69% are female.The schedule for plasma fatty acid composition measurement is as follows: at baseline, at 6 month, and yearly thereafter.The mean baseline total and low-density lipoprotein cholesterol levels were 275 mg/dL (7.1 mmol/L) and 180 mg/dL (4.6 mmol/L).Results
Results are expected in 2005.Conclusion
JELIS is a large clinical trial that will evaluate whether EPA can make an additional improvement in mortality and morbidity of coronary artery disease beyond that of HMG-CoA reductase inhibitor treatment. 相似文献995.
996.
Hepatocyte transplantation and artificial organ hepatic support require a number of functionally mature hepatocytes. However, their growth activity and functional behaviors are much smaller in culture after isolation from the liver. We examined whether continuously differentiating hepatocytes from multipotent hepatic stem cells that were isolated by using flow cytometry and propagated clonally in culture could be a source of clinical application. They actually gave rise to cells that were functionally equal to mature hepatocytes found in the adult liver, which secreted albumin into culture medium and metabolized harmful ammonium into urea. These data suggest that stem cell-derived hepatocytes are a useful cell source for developing therapeutic strategies, such as cell transplantation, gene therapy, and artificial liver organ to treat various liver disorders. 相似文献
997.
998.
Establishment of modified chimeric mice using GFP bone marrow as a model for neurological disorders 总被引:3,自引:0,他引:3
Furuya T Tanaka R Urabe T Hayakawa J Migita M Shimada T Mizuno Y Mochizuki H 《Neuroreport》2003,14(4):629-631
Chimeric mice stably reconstituted with bone marrow cells represent a good model for analysis of the mechanism of bone marrow cell infiltration in the brain. However, in preparing chimeric mice, irradiation of the recipient mice is necessary to kill their own bone marrow before transplantation, which induces gliosis and inflammatory response by activation of astrocytes and microglia in the brain. Here, we determined the most suitable dose of irradiation associated with the least brain damage before transplantation for reconstitution of chimeric mice, using FACS analysis. Our mouse model of 10 Gy body/5 Gy head irradiation should be useful for investigating the mechanism(s) of microglial activation in various neurological disorders such as stroke, Alzheimer's disease and Parkinson's disease. 相似文献
999.
Ikebe S Harada T Hashimoto T Kanazawa I Kuno S Mizuno Y Mizuta E Murata M Nagatsu T Nakamura S Takubo H Yanagisawa N Narabayashi H 《Parkinsonism & related disorders》2003,9(Z1):S47-S49
We report a consensus statement of the collaborative research group on the prevention and treatment of malignant syndrome (MS) in Parkinson's disease. The syndrome is quite similar to neuroleptic MS. Although sudden withdrawal of levodopa was the most frequent cause, many other precipitating events were found such as intercurrent infections, dehydration, hot weather, discontinuation of other anti-parkinsonian drugs, and "wearing off" phenomenon. Awareness of this syndrome is most important for its early detection and the prompt commencement of treatment. MS should be suspected whenever the body temperature rises above 38 degrees C without an apparent cause. Treatment consists of ample intravenous fluid, cooling the body, anti-parkinsonian drugs (particularly levodopa and bromocriptine), dantrolene sodium, and antibiotics if infection is present. Rhabdomyolysis, disseminated intravascular coagulation, and acute renal failure constitute serious complications. 相似文献
1000.
Yamashita S Miyamoto O Janjua NA Tomizawa K Matsui H Nakamura T Nagao S Itano T 《Brain research. Molecular brain research》2003,111(1-2):8-16
To investigate the changes in the principal subunit of N-methyl-D-aspartate (NMDA) receptor 1 (NR1) following the transient ischemia and postischemic hypothermia, in situ hybridization was used in the gerbil hippocampus. One of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors, Glutamate receptor 2 (GluR2) was also investigated to compare with NR1. Even at 1 day, NR1 and GluR2 mRNAs in the CA1 region were reduced following ischemia. Although postischemic hypothermia prevented almost all the neuronal cell death by ischemia and inhibited the reduction of NR1 and GluR2 mRNAs in the CA1 region after 7 days, the downregulation of NR1 mRNA in the CA2 region was observed even at 1 day. This change was specific for NR1 and not for GluR2. These results suggest that the changes in NR1 and GluR2 receptors at the mRNA level would occur in spite of postischemic hypothermia. The phenomenon in the CA2 region may play an important role to rescue neuronal cell death by ischemia. 相似文献