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991.
Yutaka Midorikawa Shuichi Tsutsumi Hirokazu Taniguchi Masami Ishii Yuko Kobune Tatsuhiko Kodama Masatoshi Makuuchi Hiroyuki Aburatani 《Cancer science》2002,93(6):636-643
To identify the genes associated with dedifferentiation of hepatocellular carcinoma (HCC), gene expression profiles of HCCs of well-and moderately differentiated grades were compared by means of oligonucleotide arrays. One tumor showed a nodule-in-nodule appearance (NIN), which is occasionally observed in the course of progression of HCC from well to less differentiated grade, when an inner, moderately differentiated tumor (MD) develops sequentially from the outer, well-differentiated tumor (WD). Seventy-six genes were identified to be up-regulated more than 3-fold and 33 genes were down-regulated in the inner nodule in NIN. By statistical analysis of the profiles from 10 individual additional liver tumors, 5 WDs and 5 MDs, we were able to identify 12 genes, LAMA3, PPIB, ADAR, PSMD4, NDUFS8, D9SVA, CCT3, GBAP, ARD1, RDBP, CSRP2 , and TLE1 , with significantly elevated expression, and 4 genes, CP, IL7R, CD48 , and PLGL , with decreased expression in MD. These selected genes were further validated using another 12 tumors, 5 WDs and 7 MDs, with semi-quantitative RT-PCR. We also applied neighborhood analysis to list the genes with high predictability values as most closely correlated with WD-MD distinction. Seven genes, ADAR, PSMD4, D9SVA, CCT3, GBAP, RDBP , and CSRP2 , whose expression was elevated and one gene, IL7R , whose expression was decreased, were included among the top 50 predictor genes. These genes are likely to be associated with dedifferentiation of HCC and their identification may help to elucidate the mechanism of liver cancer progression. 相似文献
992.
993.
The combined effect of Lactobacillus casei YIT9018 (LC9018) and adriamycin (ADR) on malignant pleurisy was investigated using an experimental model in BALB/c mice in which Meth A fibrosarcoma cells were intrapleurally implanted. The control mice died from dyspnea due to pleural effusion, before significant growth of tumor nodules could be achieved in the thoracic cavity. Intrapleural (ipl) administration of LC9018 (20–200 μg/head) on days 1 and 5 reduced the effusion volume and induced pleural adhesions in a dose-related manner. A statistically significant and reproducible prolongation of survival was observed at a dose of LC9018 200 μg/head: increase of lifespan (ILS) values of 15–39% were obtained. An ipl administration of ADR (2–4 mg/kg) on day 1 was also effective in prolonging survival without severe toxicity (ILS values of 100–122%). The combined use of ADR and LC9018 induced a high incidence of pleural adhesions, a delay in effusion accumulation, and an additive prolongation of lifespan (ILS values of 133–178%), compared with ADR monotherapy. In the combination therapy group, a marked and continuous ipl exudation of neutrophils, macrophages, and lymphocytes was observed with a significant decrease in pleural tumor cells. These findings suggest that ipl administration of LC9018 enhances the effect of ADR, probably through both host-mediated tumoricidal activity and sclerosing effects on the pleura. 相似文献
994.
Carcinogenicity in rats of a mutagenic compound, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline 总被引:16,自引:1,他引:15
Kato Tamami; Ohgaki Hiroko; Hasegawa Hirokazu; Sato Shigeaki; Takayama Shozo; Sugimura Takashi 《Carcinogenesis》1988,9(1):71-73
Carcinogenicity of 2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline(MeIQx), which is a potent mutagen first isolated from friedbeef and widely present in various cooked foods, was testedin both sexes of F344 rats. Rats were continuously given a dietcontaining 0.04% MeIQx or basal diet and the experiment wasfinished on day 429. In experimental animals, the incidenceof liver, Zymbal gland, clitoral gland and skin tumors was significantlyhigher than in control animals. The incidence of liver tumorswas 100% in males and 53% in females; most liver tumors of maleswere hepatocellular carcinomas and all liver tumors of femaleswere neoplastic nodules. The incidence of Zymbal gland tumorswas 75% in males and 53% in females. Clitoral gland tumors wereinduced in 63% and skin tumors were observed in 35% of malesand 5% of females. Most of these three types of tumors werediagnosed as squamous cell carcinoma. In the control rats, liver,Zymbal gland, clitoral gland and skin tumors were not observedin either sex. 相似文献
995.
K Matsumoto K Onoda K Tsuno H Shigematsu T Matsuhisa T Maeshiro N Mishima T Furuta A Nishimoto 《No shinkei geka. Neurological surgery》1991,19(10):985-989
A case of primary intracranial germinoma in the left basal ganglia treated with interstitial brachytherapy was reported. A 15-year-old boy was referred to our hospital for evaluation of right hemiparesis. A CT scan showed a slightly hyperdense mass with multiple cystic low density in the left basal ganglia. The mass was heterogeneously enhanced after intravenous administration of contrast material. T1 weighted image showed a slightly hyperintense mass with cystic components and the mass was heterogeneously enhanced with Gd-DTPA. T2 weighted MR image showed a mixed intensity mass and peritumoral edema. Stereotactic needle biopsy and implantation of 3 catheters for interstitial brachytherapy were performed simultaneously using BRW CT guided stereotactic apparatus. After the histological diagnosis was confirmed to be two cell pattern germinoma, 9 iridium-192 seeds were inserted into the catheters and maintained for 10 days to give 35Gy of irradiation at the tumor periphery. Subsequent CT scans showed marked tumor regression and the clinical symptoms were improved. Germinoma originating in the basal ganglia is rare and hard to diagnose previous to biopsy. Histological confirmation is essential before initiation of treatment because germinoma is commonly thought to be radiosensitive tumor. The interstitial brachytherapy enables selective irradiation of the tumor and actually causes no complications such as bone marrow suppression or cerebral atrophy. The neuroradiological findings, especially of CT scan and MRI, were presented and the strategy for treatment of germinoma in basal ganglia was discussed. 相似文献
996.
Synthesis, stereochemistry, and biological properties of the depigmenting agents, melanostatin, feldamycin and analogs. 总被引:1,自引:0,他引:1
K Imae H Kamachi H Yamashita T Okita S Okuyama T Tsuno T Yamasaki Y Sawada M Ohbayashi T Naito 《The Journal of antibiotics》1991,44(1):76-85
Syntheses of melanostatin and feldamycin have been completed from L-serine and L-threonine, respectively, and the configuration of unknown asymmetric carbons determined. Feldamycin analogs have also been prepared and the L-tryptophyl analog was the most potent in the depigmentation of Streptomyces bikiniensis and B16 melanoma cells. 相似文献
997.
998.
Ken-ichiro Yamashita Takuo Nomura Yasumasa Ohyagi Takayuki Taniwaki Hirokazu Furuya Yasuo Kuwabara Jun-ichi Kira 《Clinical neurology》2005,45(5):351-356
We report a 52-year-old woman with primary progressive multiple sclerosis (PPMS) presenting with chronic progressive memory impairment. From a couple of years prior to admission, she had developed impairment of her short-term memory. For example, she forgot her nephew's name, and spoke the same phrases again and again. She also sometimes forgot to turn off her gas stove and forgot things she bought in shops. Moreover, her mental activity gradually decreased and she became apathetic. However, she did not note her memory impairment, and had no hallucinations. She was admitted to our hospital on 20 May, 2003 because donepezil had been ineffective for treating her memory impairment. Neurologically, she showed bilateral horizontal gaze nystagmus, mild limb ataxia on the left and mildly ataxic gait. Neuropsychological examinations showed mildly impaired cognitive function, e.g., MMSE 25/30, WAIS-R full IQ 69 and especially in verbal short memory, which may represent temporal lobe dysfunction. Moreover, Benton's visual memory test revealed marked visual short-term memory impairment, while impaired performance on a Kana picking up test suggested mild to moderate attention impairment, which could have represented frontal lobe dysfunction. Brain MRI showed multiple T2-high plaque lesions close to the bilateral lateral ventricles, and bilateral optic nerve lesions enhanced by gadolinium. Also, spinal cord MRI showed a gadolinium enhanced lesion at Th5 on the left. Cerebral spinal fluid (CSF) examination showed normal cell count and protein level, and undetectable oligoclonal bands (OCB), but an elevated IgG index (1.1, normal < 0.85). Visual evoked potentials (VEPs) showed prolonged P100 latency bilaterally, indicating subclinical optic nerve lesions. She was thus diagnosed as having PPMS according to McDonald's diagnostic criteria for MS. 99mTc Single photon emission computed tomography (SPECT) showed a decreased cerebral blood flow (CBF) in the bilateral frontal and temporal lobes, which was consistent with her clinical features. PPMS patients generally present with chronic progressive spastic paraparesis and/or cerebellar ataxia. Cognitive impairments observed in PPMS are generally thought to be due to white matter lesions, i.e., subcortical dementia. However, some recent reports have shown MS patients with short-term memory impairment (antegrade amnesia) similar to cortical dementias such as Alzheimer's disease (AD). In such MS cases, visual short-term memory impairment seems characteristic of their cognitive impairment compared to AD cases. As well, the present case showed visual memory impairment as evaluated by Benton's memory test. Parietal and frontal lobes are reported to be important for verbal and visual working memory, respectively. Thus, in the present case, decreased CBF in the frontal and temporal lobes, which could have been due to a disconnection between cortices and subcortices caused by the white matter lesions, is consistent with the type of her cognitive dysfunction, i.e., notable visual memory impairment. PPMS may thus be an important disease as a differential diagnosis for chronic progressive dementia. Further neuropsychological and functional imaging studies will be necessary to achieve a better understanding of the mechanisms of cognitive impairment in PPMS. 相似文献
999.
Masako Taga Takashi Abe Susumu Nishimura Hirokazu Kimura Mariko Oki Masanori Nojima Hiroki Tanaka Shinichiroh Matsumoto Kohzoh Imai 《Nihon Rinshō Men'eki Gakkai kaishi》2003,26(6):336-340
A 68-year-old female had been treated for chronic type C hepatitis at our department since June, 1992. In August of the same year, swelling of the right eyelid developed and she was diagnosed as having sarcoidosis on the basis of uveitis, skin lesions, and bilateral hilar lymphadenopathy (BHL) on chest X-ray. With steroid therapy, the symptom improved and BHL disappeared. In July, 2001, dryness of the mouth and dry eyes developed, and she was diagnosed as having Sj?gren's syndrome (SjS). This case may be precious in discussing the pathophysiology of sarcoidosis and SjS including the association with hepatitis C virus infection. 相似文献
1000.
Inhibitory effects of n-3 polyunsaturated fatty acids on sigmoid colon cancer transformants 总被引:7,自引:0,他引:7
Wen-Sy Tsai Hirokazu Nagawa Shoichi Kaizaki Takashi Tsuruo Tetsuichiro Muto 《Journal of gastroenterology》1998,33(2):206-212
Various types of polyunsaturated fatty acids (PUFAs) have been suggested to exert different effects on the colon in terms
of promotion or inhibition of tumor development. Results of in vitro and in vivo studies are, however, inconsistent and it
remains unclear whether or not the cellular effects of PUFAs change along with the malignant transformation of colonic cells.
In this study, we used the NIH3T3 cell line and its SIC (sigmoid colon cancer) oncogene transformants to compare the effects
of PUFAs on the proliferation of non-malignant and malignant cells. We also determined the cellular utilization of fatty acids
in media by a high-performance liquid chromatography method. The addition of exogenous arachidonic acid (ARA, an n-6 fatty
acid), eicosapentaenoic acid (EPA, n-3), and docosahexaenoic acid (DHA, n-3) exerted different effects on NIH3T3 cells, and
on SIC transformants, in which selective inhibitory effects were observed at media concentrations ranging from 10 to 20 μg/ml.
In cells cultured in media supplemented with EPA or DHA at a concentration of 2 μg/ml, which had no effect on cell proliferation,
the cellular utilization of linoleic acid (n-6), a precursor of n-3 fatty acids, was inhibited. This inhibition was stronger
in SIC transformants than in NIH3T3 cells (P < 0.05). There was no difference in the utilization of fatty acids between the two cell lines cultured in media supplemented
with ARA. We conclude that the cellular response to exogenous long-chain PUFAs is modified during the course of malignant
transformation, and that EPA and DHA (n-3 PUFAs) appear to have specific inhibitory effects on cancer cells and may thus enhance
the host defense against colon cancer.
(Received Dec. 10, 1996; accepted July 25, 1997) 相似文献