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81.
Somatic mutations of epidermal growth factor receptor in colorectal carcinoma.   总被引:11,自引:0,他引:11  
PURPOSE: Somatic mutations of the epidermal growth factor receptor (EGFR) gene may predict the sensitivity of non-small cell lung carcinoma to gefitinib. However, no mutations have been reported for colorectal carcinoma. We therefore analyzed EGFR mutations in colorectal adenocarcinomas by the combined use of laser microdissection and sequencing of genomic DNA. EXPERIMENTAL DESIGN: We examined 11 representative colorectal adenocarcinoma cell lines and 33 clinical samples of colorectal carcinoma. In the clinical cases, we carefully dissected only carcinoma cells from frozen sections by laser microdissection. After DNA extraction and PCR, we examined EGFR mutations by sequencing genomic DNA. RESULTS: None of 11 colorectal carcinoma cell lines exhibited somatic mutations, but 4 of 33 clinical tumors (12%) exhibited mutations in the EGFR kinase domain. This may be the first report of somatic mutations in colorectal adenocarcinoma. CONCLUSIONS: Our findings suggest that a distinct minority of colorectal adenocarcinomas exhibit somatic mutations of EGFR, and these tumors may be susceptible to gefitinib treatment.  相似文献   
82.
PURPOSE: Squamous cell carcinoma (SCC) and adenocarcinoma of the lung are currently subject to similar treatment regimens despite distinct differences in histology and epidemiology. The aim of this study is to identify a molecular target with diagnostic and therapeutic values for SCC. EXPERIMENTAL DESIGN: Genes specifically up-regulated in SCC were explored through microarray analysis of 5 SCCs, 5 adenocarcinomas, 10 small cell lung carcinomas, 27 normal tissues, and 40 cancer cell lines. Clinical usefulness of these genes was subsequently examined mainly by immunohistochemical analysis. RESULTS: Seven genes, including aldo-keto reductase family 1, member B10 (AKR1B10), were identified as SCC-specific genes. AKR1B10 was further examined by immunohistochemical analysis of 101 non-small cell lung carcinomas (NSCLC) and its overexpression was observed in 27 of 32 (84.4%) SCCs and 19 of 65 (29.2%) adenocarcinomas. Multiple regression analysis showed that smoking was an independent variable responsible for AKR1B10 overexpression in NSCLCs (P < 0.01) and adenocarcinomas (P < 0.01). AKR1B10 staining was occasionally observed even in squamous metaplasia, a precancerous lesion of SCC. CONCLUSION: AKR1B10 was overexpressed in most cases with SCC, which is closely associated with smoking, and many adenocarcinoma cases of smokers. These results suggest that AKR1B10 is a potential diagnostic marker specific to smokers' NSCLCs and might be involved in tobacco-related carcinogenesis.  相似文献   
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84.
Lipid peroxidation and oxidative stress may play a certain role in the pathogenesis of pressure-induced atherosclerosis, and alcohol related diseases. Recently, 8-isoprostane in biological fluids has been reported to be a reliable marker for lipid peroxidation and oxidative stress in vivo. In the present study, we developed an ELISA method for 8-isoprostane which has high sensitivity, intra- and inter-assay reproducibility and wide dynamic assay range. Using this method, we examined the effects of drinking and smoking habits on plasma levels of 8-isoprostane in healthy subjects. A total of 157 apparently healthy volunteers was assayed for plasma 8-isoprostane. Subjects were divided into three groups according to their alcohol consumption. Group I is non- or few-drinkers, Group II includes subjects who drink once or twice a week, and subjects of Group III intake 3 to 5 times a week or almost every day. In addition, the same population was divided into two groups, 96 non-smokers and 61 smokers. Plasma 8-isoprostane was extracted with ODS gel followed by NH2 Sep-Pak column. The 8-isoprostane fractions thus separated were assayed by a commercial ELISA kit (Cayman Chemical). The plasma 8-isoprostane was estimated to be 20.9 +/- 93 pg/ml in a total of 157 volunteers (83 male, 74 female). The plasma 8-isoprostane levels were elevated in the Group III (26.6 +/- 9.5 pg/ml) compared with Group I (20.3 +/- 6.1 pg/mL, p<0.0001) and Group II (20.9 +/- 5.7 pg/ml, p<0.001). Significant increase of the plasma 8-isoprostane was observed only in habitual drinkers of females, but not in those of males. On the other hand, no significant difference of the plasma 8-isoprostane levels were observed between non-smokers (21.5 +/- 7.3 pg/ml) and smokers (22.8 +/- 7.4 pg/ml, p>0.05). We suppose that plasma 8-isoprostane may increase in the habitual drinkers due to the oxidization stress induced by alcohol intake, and it may become a useful marker to estimate drinking habit  相似文献   
85.
We examined the effectiveness of stereotactic radiation surgery (SRS) in 14 patients with brain metastasis in our hospital. The age of the patients ranged 45–85 years old (mean, 65). Brain metastasis was detected by neurological symptoms in seven patients and by regular imaging examination in the remaining patients. The number of metastatic lesions in the brain before SRS ranged 1–11 (median, 2). The treatment number of SRS was 1–4 times (median, 2). Six of 14 patients had neurological symptoms before SRS. Overall survival (OS) after SRS was 1.7–21.2 months (median, 8.2). The progression‐free survival (PFS) after SRS was 0.9–10.5 months (median, 2.2). The result of univariate analysis showed that the application of two or more courses of SRS was significantly related to OS (= 0.005). Single metastatic lesion (P = 0.051) and no extracranial lesion (P = 0.055) showed a slight tendency to be related to disease‐free survival (DFS). Neither lactate dehydrogenase nor neurological symptoms were significantly related to OS or DFS. Although OS and DFS after SRS were not very long, the treatment of brain metastases has the potential to prevent neurological events. Repeating SRS may be accepted as a local therapy in the multimodal approach including new molecular targeting drugs for metastatic melanoma.  相似文献   
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87.
Lupus erythematosus profundus (LEP) is a variant of lupus erythematosus, involving the deep dermis and subcutaneous fat. LEP is characterized by the presence of lymphoid follicles (LF) and germinal centers (GC). However, it remains unknown whether these lymphoid structures correspond to the lymphoid tissues such as cutaneous tertiary lymphoid organs (TLO). Previously, we identified dynamically orchestrated cellular elements in murine contact dermatitis that resembled lymphoid structures, which we termed inducible skin‐associated lymphoid tissues (iSALT). We subsequently reported structures analogous to iSALT in human secondary syphilis, suggesting that iSALT can also exist in humans. Here, we studied ectopic lymphoid tissues in the lesions of LEP by immunohistochemistry and compared their characteristics with those of TLO. We demonstrated that LF of LEP were composed of B‐cell follicles intermingled with CXCL13‐expressing cells, distinct aggregations of T cells, and some blood vessels expressing peripheral node addressin. These findings indicate that LF of LEP can be considered as a type of iSALT.  相似文献   
88.
We examined dermoscopic features of three cases of extraocular sebaceous carcinoma and reviewed the literatures. The yellowish structures, polymorphous vessels and ulceration were common findings in our cases and all cases of the previous reports. The appearance of whitish‐pink areas has not been described previously. Our results suggested that the combination of four dermoscopic features, whitish‐pink areas, yellowish structures, polymorphous vessels and ulceration might be distinctive in extraocular sebaceous carcinoma.  相似文献   
89.
ObjectivesEating alone is associated with an increased risk of depression symptoms. This association may be confounded by poor social networks. The present study aimed to determine the role of poor social networks in the association of eating alone with depression symptoms, focusing on cohabitation status.MethodsSeven hundred and ten community-dwelling older adults were categorized according to their eating style and social network size, evaluated using an abbreviated version of the Lubben Social Network Scale, with poor social network size (defined as the lowest quartile). Living arrangements and depression symptoms, detected using the Zung Self-Rating Depression Scale, were also assessed.ResultsA mixed-design two-way analysis of covariance (eating style and social network size factors) for the depression scale score, adjusted by covariates, yielded significant effects of social network size and eating style without interaction. Greater depression scores were observed in eating alone and poor social network size. Analysis of participants living with others showed the same results. However, among older adults living alone, only a significant main effect of social network size was observed; poor social network size resulted in greater depression scores irrespective of eating style.ConclusionsPoor social network size, and not eating alone, was associated with greater depression symptoms among older adults living alone, whereas both factors may increase depression symptoms among older adults living with others. Poor social network size may show a stronger influence on depression than eating alone in older adults living alone; thus, social network size is an important health indicator.Key words: eating alone, social network, living alone, depression, older adults  相似文献   
90.
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