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991.
Nishimura N Matsushita Y Takaoka K Hashitani S Noguchi K Urade M 《Gan to kagaku ryoho. Cancer & chemotherapy》2002,29(13):2537-2539
Hypercalcemia of malignancy is a common problem for cancer clinicians. Treatment of hypercalcemia of malignancy with pamidronate in a patient with advanced recurrent oral cancer is reported herein. The patient was a 36-year-old man who had neck lymph node metastases due to recurrence of squamous cell carcinoma of the buccal mucosa and complained of cloudiness of consciousness due to hypercalcemia. The patient was administered pamidronate. A fine reduction in serum calcium was observed and cloudiness of consciousness was also alleviated. Although treatment of hypercalcemia with pamidronate is palliative, it is effective against the deterioration of quality of life. 相似文献
992.
Differential gene expression profiles of gastric cancer cells established from primary tumour and malignant ascites 总被引:18,自引:0,他引:18
993.
Different genetic alterations in rat forestomach tumors induced by genotoxic and non-genotoxic carcinogens 总被引:4,自引:0,他引:4
Kaneko M Morimura K Nishikawa T Wanibuchi H Takada N Osugi H Kinoshita H Fukushima S 《Carcinogenesis》2002,23(10):1729-1735
Human beings are exposed to a multitude of carcinogens in their environment, and most cancers are considered to be chemically induced. Here we examined differences in genetic alterations in rat forestomach tumors induced by repeated exposure to a genotoxic carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or N-methylnitrosourethane (MNUR), and chronic treatment with a non-genotoxic carcinogen, butylated hydroxyanisole (BHA) or caffeic acid (CA). A total of 132, 6-week-old male F344 rats were employed. Forty rats were treated with MNNG by intragastric administration at a dose of 20 mg/kg body wt once a week for 32 weeks, and 20 rats received 20 p.p.m. MNUR in their drinking water for 48 weeks. Further groups of 20 animals were administered 2% BHA or 2% CA in the diet for 104 weeks. The remaining rats were maintained without any supplement as controls. Multiple forestomach tumors were observed in all rats of the MNNG-, MNUR-, BHA- and CA-treated groups. Histopathologically, MNUR- and CA-treated groups showed almost the same pattern. On polymerase chain reaction-single strand conformation polymorphism analysis, H-ras and p53 gene mutations were observed at high and relatively low frequencies, respectively, in forestomach tumors induced by MNNG and MNUR. Most H-ras gene mutations were G-->A transitions in codons 7 and 12 of exon 1. On the other hand, forestomach tumors due to the non-genotoxic carcinogens, BHA and CA, had almost no mutations of the H-ras and p53 genes. Moreover, relative overexpression of cyclin D1 and p53 was detected in forestomach tumors induced by the genotoxic carcinogens, while their non-genotoxic counterparts had a tendency to show low expression of those molecules. Mutations of the beta-catenin gene were not detected in any group. The present study demonstrates that rat forestomach tumors induced by genotoxic and non-genotoxic carcinogens have different underlying genetic alterations, even if their pathological features are similar. 相似文献
994.
Enhanced Apoptosis in Pilocytic Astrocytoma: A Comparative Study of Apoptosis and Proliferation in Astrocytic Tumors 总被引:5,自引:0,他引:5
Nakamizo A Inamura T Ikezaki K Yoshimoto K Inoha S Mizoguchi M Amano T Fukui M 《Journal of neuro-oncology》2002,57(2):105-114
Both cell proliferation and cell death occur simultaneously in tumor tissue, and extent of tumor growth reflects the net balance of these events. We correlated cell proliferation, spontaneous cell death, and alterations in tumor suppressor proteins with one another and with survival of patients with primary astrocytic tumors. In 39 astrocytic tumor specimens (6 pilocytic astrocytomas, 14 fibrillary astrocytomas, 9 anaplastic astrocytomas, and 10 glioblastomas), we determined the MIB-1 labeling index, the apoptotic ratio according to nick end labeling with morphologic confirmation, the p53 labeling index, and the presence of p53 or PTEN mutations.MIB-1 labeling indices of pilocytic astrocytomas, fibrillary astrocytomas, anaplastic astrocytomas, and glioblastomas were 0.30±0.32; 1.84±1.87; 19.3±6.42; and 28.0±14.5 (mean±SD), respectively. Corresponding apoptotic ratios were 17.9±5.16; 3.96±3.57; 1.18±0.93; and 2.11± 1.60 (mean±SD). The apoptotic ratio in pilocytic astrocytomas was significantly higher than in other astrocytic tumors (fibrillary astrocytomas, p<0.05; anaplastic astrocytomas and glioblastomas, p<0.01). MIB-1 showed a significant negative correlation with apoptosis (p<0.01). MIB-1 and apoptosis showed significant negative and positive correlations with patient survival (p<0.01). Mutations of p53 and PTEN show no correlation with survival and apoptotic ratio.The apoptotic ratio can clearly distinguish pilocytic astrocytomas from other tumors, and this biological feature may reflect less aggressive growth of pilocytic astrocytomas. 相似文献
995.
Shibata M Nezu T Kanou H Nagata Y Kimura T Takekawa M Ando K Fukuzawa M 《Cancer investigation》2002,20(2):166-173
It is well known that cell-mediated immunity is suppressed in patients with neoplastic diseases. We have reported that soluble receptors for interleukin-2 (sIL-2R) and tumor necrosis factor (sTNF-R1) are elevated in the serum of patients with advanced colorectal cancer. The presence of these soluble receptors and immunosuppressive cytokines, including interleukin-10 (IL-10), might be important in the mechanisms of immunosuppression. cis-Diaminedichloroplatinum (cisplatin) has been reported to immunomodulate, especially when used in low dose in combination with 5-Fluorouracil (5-FU). In this study, cisplatin and UFT, a form of uracil and tegafur which is a prodrug of 5-FU, were administered with immunomodulator Polysaccharide K (PSK) to ten patients with colorectal cancer, who showed distant metastasis in the liver or lung, and the serum levels of sIL-2R and sTNF-R1 and the production of gamma-interferon (gamma-INF) and interleukin-10 by peripheral blood mononuclear cells were measured. The serum concentrations of sIL-2R and the production of IL-10 were reduced (p < 0.05) after 2 months of treatment. Thus, this combination appeared to have immunomodulative potential in patients with advanced colorectal cancer. 相似文献
996.
A long-lasting dizzy sensation is a common complaint in elderly subjects. The pathogenesis and effective treatment of such chronic dizziness (CD), however, have not yet been fully elucidated because of lack of methods for evaluating this sensation. On the basis of assumption that CD may be attributable partly to cortical functional abnormality, we attempted to estimate the function of auditory cortex by measurements of auditory-evoked magnetic fields (AEFs). Magnetic field signals in the parieto-temporal cortex were evoked by 1000-Hz tone-burst with 90-dB normal hearing level sounds, and the highest-amplitude magnetic waveforms at approximately 100-ms (N100m) were analyzed as electrical current arrows in normal subjects (n=11), patients with CD (n=27) and patients with cerebral infarction but no dizzy sensation (n=9). In the normal subjects, the current arrows pointed to a nearly straight line with small directional distortion as indicated by a rotation-degree parameter, dI(rot) of 1.59+/-0.46. In 17 of 27 CD patients, the directions of current arrows were markedly distorted showing abnormally high dI(rot) values greater than 2.50 (the mean plus two standard deviations of normal values) and disclosed a clockwise or counter-clockwise rotation in either side or both sides of parieto-temporal cortex. In all the patients with cerebral infarction, the current arrows exhibited the similar pattern as the normal subjects. None of them exhibited abnormally high dI(rot) values. We hypothesized that the rotational abnormality may be caused by abnormal neuronal excitation, since non-evoked magnetic fields in temporal lobe epilepsy demonstrated the similar current rotational abnormality as reported previously. Seven CD patients were treated with anticonvulsants, and four showed remarkable amelioration of dizzy sensation. In all the four patients with symptomatic amelioration, the disappearance of rotational abnormality in AEFs or the tendency towards disappearance was observed following symptomatic amelioration. The results of the present study suggest that the auditory center may contribute to the maintenance of equilibrium, and its dysfunction may lead to the development of CD. AEFs measurements may make it possible to evaluate the functional abnormality of auditory center and may be useful for studying the pathophysiology and treatment of CD. 相似文献
997.
998.
Voxel-based comparison of regional cerebral glucose metabolism between PSP and corticobasal degeneration 总被引:7,自引:0,他引:7
Hosaka K Ishii K Sakamoto S Mori T Sasaki M Hirono N Mori E 《Journal of the neurological sciences》2002,199(1-2):67-71
OBJECTIVES: Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are neurodegenerative disorders that may be accompanied by dementia and parkinsonism as clinical symptoms. The purpose of this study was to elucidate cerebral metabolic differences of these two diseases with cognitive impairments by [18F] fluorodeoxyglucose (FDG) and positron emission tomography (PET). METHODS: A total of 12 patients with PSP (age: 62.8+/-6.0 years old, m: 7, f: 5, Mini-Mental State Examination (MMSE): 23.4+/-2.6), 12 patients with CBD (age: 64.8+/-6.3 years old, m: 6, f: 6, MMSE: 22.9+/-4.5), and age-matched healthy subjects (normal control (NC)) (age: 63.8+/-7.7 years old, m: 7, f: 5) were subjected to FDG-PET to obtain glucose metabolic images. We compared regional cerebral metabolic images by a voxel-by-voxel analysis with statistical parametric mapping (SPM) among PSP, CBD, and NC subjects, and evaluated differences of hypometabolic regions. RESULTS: The patients with PSP showed reduced cerebral glucose metabolism in the medial and lateral frontal gyri, basal ganglia, and midbrain compared with NC, whereas the patients with CBD showed significant reduction in the parietal lobes (p<0.001). SPM also revealed parietal hypometabolism in CBD patients compared with PSP patients (p<0.001). CONCLUSIONS: The predominant parietal glucose metabolic reduction in CBD patients was different from previously reported findings. This finding would be the characteristic substance of patients with CBD accompanying cognitive impairments. Our findings suggest that measurement of glucose metabolism by PET and a voxel-based analysis is useful to understand the pathophysiology of these two diseases with cognitive impairments. 相似文献
999.
Hayakawa H Shirai M Sato A Yoshizawa Y Todate A Imokawa S Suda T Chida K Tamura R Ishihara K Saiki S Ando M 《Respirology (Carlton, Vic.)》2002,7(4):359-364
OBJECTIVE: Only limited information exists concerning the clinical and pathological features of chronic hypersensitivity pneumonitis (HP) in Japan and elsewhere. We present data on clinicopathological features of chronic HP obtained through a Japanese nationwide survey. METHODOLOGY: We studied the clinical and pathological findings in 10 patients with chronic HP who underwent surgical lung biopsy or postmortem examination. RESULTS: There were three types of clinical course: six of the 10 patients had persistent symptoms followed by repeated acute episodes; two showed a subacute onset with persistent symptoms; and two exhibited an insidious onset. Five patients made no attempt to avoid antigen exposure and they all had progressive disease. Pathological findings indicated that lesions were mainly centrilobular with or without epithelioid cell granulomas in specimens obtained during the acute or subacute stage. In contrast, most patients in the chronic stage predominantly showed interstitial fibrosis with a usual interstitial pneumonia pattern. CONCLUSIONS: The pathological findings of chronic HP depend on the stage of the disease at tissue sampling. 相似文献
1000.
Increased synthesis of calcitonin gene-related peptide stimulates keratinocyte proliferation in murine UVB-irradiated skin 总被引:2,自引:0,他引:2
Seike M Ikeda M Morimoto A Matsumoto M Kodama H 《Journal of dermatological science》2002,28(2):135-143
Repeated ultraviolet (UV) irradiations have been shown to induce keratinocyte proliferation with acanthosis, stimulate the cutaneous nerve proliferation, and increase the synthesis of calcitonin gene-related peptide (CGRP). In the current study, we examined the role of CGRP in the UVB-induced proliferation of murine keratinocytes. UVB irradiation increased the number of bromodeoxyuridine (BrdU)-labeled basal keratinocytes and caused acanthosis. In addition, CGRP expression was up-regulated in the peripheral nerves of the upper dermis and lower epidermis. Repeated intradermal injections of CGRP increased the number of BrdU-labeled basal cells and caused acanthosis. Intradermal injections of capsaicin prior to UVB-irradiation inhibited the UVB-induced CGRP expression, BrdU labeling in basal keratinocytes and epidermal thickening. Intradermal injections of anti-CGRP antibody inhibited the UVB-induced BrdU labeling in basal keratinocytes, but epidermal thickening was not significantly inhibited. These results indicate that CGRP is one of the stimulators to UVB-induced keratinocyte proliferation. On the other hand, expression of substance P, another neuropeptide in the peripheral nerve, was not up-regulated by UVB irradiation. 相似文献