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991.
Association of gene alterations and prognosis has not fully been elucidated in hepatocellular carcinoma (HCC). To clarify the relationship between p53 and hMSH2 mutations and prognosis, we analysed these mutations in 83 HCC cases and assessed their association with various clinicopathological factors. The 3-year disease-free survival (DFS) or overall survival (OS) rates in HCC patients with p53 mutation and p53 wild/hMSH2 mutation significantly decreased compared with those without these mutations (14.3% and 37.5% versus 67.5% for DFS; 35.7% and 50.0% versus 96.4% for OS, respectively). In the multivariate analysis, categories by p53 and hMSH2 mutation status, and liver cirrhosis demonstrated statistical significances for DFS and OS. Moreover, the frequency of patients with p53 and/or hMSH2 mutations in intrahepatic metastasis (75.0%) was significantly higher than that in multicentric occurrence (14.3%). Thus, p53 and hMSH2 mutations will be useful for identifying subsets of HCC patients with poor prognosis.  相似文献   
992.
Malignant transformation is caused by multi-step genetic mutations, and growth factors are believed to play important roles in developing and maintaining malignant phenotype. However, there is no direct evidence that a specific growth factor contributes to malignant transformation of phenotypically normal cells. In order to assess the function of Acrogranin (also known as granulin epithelial precursor; GEP) in ovarian carcinogenesis, ovarian surface epithelial (OSE) cells, which are supposed to be the origin of primary ovarian epithelial cancer, were transfected with combined genes of hTERT, SV40 LT, and Acrogranin. Introduction of hTERT and SV40 LT was sufficient for immortalizing OSE cells but not enough for tumor formation in nude mice. In contrast, transfection and overexpression of Acrogranin in immortalized OSE cells showed augmented clonogenicity in soft agar and obvious tumorigenicity in nude mice. This is the first study showing evidence that a specific growth factor plays a direct role in malignant transformation in ovarian cancer development.  相似文献   
993.
Recent epidemiological studies have indicated that high dietary consumption of fruit and vegetables results in lower risk of bladder cancer. To confirm these findings, we investigated in the current study the effects of dietary administration with beta-cryptoxanthin extracted from Citras unshiu oranges on N-butyl-N-(4-hydroxybutyl)nitrosamine (OH-BBN)-induced urinary bladder carcinogenesis in mice. Male ICR mice were divided into 6 experimental and control groups. Groups 1 through 4 were given OH-BBN (500 ppm) in drinking water for 6 weeks to induced urinary bladder neoplasms. Mice in groups 2, 3 and 4 were fed the diets mixed with 1, 5 and 25 ppm of beta-cryptoxanthin, respectively, starting 1 week after the cessation of OH-BBN exposure, and kept on these diets for 24 weeks until the termination of the study. Group 5 was treated with the diet containing the test compound (25 ppm) alone, and group 6 served as an untreated control. All animals were sacrificed at week 32 for histopathology and immunohistochemistry (cyclin D1). Feeding with beta-cryptoxanthin decreased the incidence and multiplicity of preneoplastic and neoplastic lesions of urinary bladder. Notably, the highest dose (25 ppm) of the test chemical significantly lowered the occurrence of bladder carcinoma, in conjunction with reducing the cyclin D1-positive cell ratio. These findings suggest that beta-cryptoxanthin is able to prevent OH-BBN-induced bladder carcinogenesis in mice.  相似文献   
994.
Bone-marrow-derived cells (BMDCs) transdifferentiate into various types of gastrointestinal cells. The precise transdifferentiation of BMDCs in gut regeneration, however, is controversial. In this study, we examined the transdifferentiation of BMDCs in the regeneration of damaged colonic epithelia. Lethally irradiated wild-type female mice (C57BL/6) were rescued by bone marrow transplantation from male green fluorescent protein transgenic mouse donors. Chronic colitis was induced by administering 3% dextran sulfate sodium (DSS) in the drinking water for 5 days on day 28 after the bone marrow transplantation. The mice were killed on day 25 after DSS administration. BMDC phenotypes were examined by confocal microscopy and fluorescence immunohistochemistry. BMDCs were frequently observed in the vimentin-positive colonic interstitial cells, which also expressed alpha-smooth muscle actin and had a spindle-like morphology, but did not express leukocyte common antigen. Green-fluorescent-protein-positive cells were rarely or less frequently found in Ki-67-positive proliferating cells, cytokeratin-positive epithelial cells, or CD31-positive endothelial cells. BMDCs frequently transdifferentiated into subepithelial myofibroblasts and fibroblasts, and often continued to reside in the colonic subepithelia after the experimental colitis had healed. In conclusion, our data indicate the fate of BMDCs, which might be involved in the healing process of the colon after DSS-induced colitis. Our data show that BMDCs contribute to colonic interstitial cells after the colitis has healed. Understanding the fate of BMDCs may be important for stem cell therapy by BMDCs.  相似文献   
995.
996.
Associations between neuroleptic side effects and plasma concentrations of the drug and prolactin were investigated in 33 acutely exacerbated schizophrenic patients (16 males and 17 females) treated with a fixed dose of nemonapride (18 mg/day), a new substituted benzamide, for 3 weeks. The most frequently observed side effects during nemonapride treatment were extrapyramidal symptoms such as akathisia (69.7%), dystonia (48.5%), hypokinesia (45.5%), tremor (39.4%) and increased salivation (36.4%). There were positive correlations between prolactin response and extrapyramidal side effects (EPS) scores after 1 week (Spearman rank correlation rs=.651, P<.01), 2 weeks (rs=.567, P<.05) and 3 weeks (rs=.670, P<.01) in male patients although no significant correlations were found in female or total patients. No significant correlations were found between plasma concentrations of the drug and total or any subscale side effects scores. The present study thus suggests that the spectrum of nemonapride-induced side effects is characterized by predominant extrapyramidal symptoms, and that prolactin response as an index of dopamine blockade reflects severity of EPS at least in male patients treated with nemonapride.  相似文献   
997.
The gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH), are of particular importance in ovarian physiology. However, FSH receptors and LH receptors are not expressed until the secondary follicle stage, indicating that initiation of follicular growth is independent of the gonadotropins. Among many intra-ovarian growth factors, many studies have shown that bone morphogenetic proteins (BMPs) play pivotal roles in regulating the early phases of follicular growth. The BMP system induces the gonadotropin system by modulating gonadotropin receptors in early-stage follicles. Interestingly, the BMP system also prevents precocious maturation of the follicle by suppressing luteinization. Signals provoked by the preovulatory LH surge eliminate BMPs, enabling luteinization to progress. Thus, the BMP system and the gonadotropin system seem to cooperate in regulating follicular development, maturation, and luteinization.  相似文献   
998.
999.
1000.
A 71-year-old man was initially given a diagnosis of pulmonary nontuberculous mycobacterial infection due to Mycobacterium intracellulare (M. intracellulare). The patient was admitted because chest roentgenogram and CT scanning showed a progression of infiltrating shadows in the bilateral upper lung fields. Aspergillus fumigatus was identified by bronchial lavage. The patient was found to have chronic necrotizing pulmonary aspergillosis with M. intracellulare and treated with voriconazole (VRCZ). After fifteen days of treatment, he complained of dyspnea and cough. A chest CT showed new diffuse ground glass opacity in the left lower lobe. Arterial blood gas analysis demonstrated severe hypoxemia. Due to concerns about drug-induced lung injury, voriconazole was discontinued and corticosteroid therapy was started. VRCZ was replaced by micafungin. Thereafter, symptoms and left lower shadows resolved. Although the lymphocyte stimulation test for voriconazole was negative, we considered that this pulmonary lesion may have been an adverse reaction to voriconazole.  相似文献   
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