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Background

Clear cell renal cell carcinoma (ccRCC) is known to occur across the adult lifetime traversing the spectrum of age-related organismal changes. Little is known as to how the aging process may affect the course of renal cell carcinoma (RCC) and the repertoire of genes involved.

Methods

Using The Cancer Genome Atlas (n?=?436) and Cancer Genomics of the Kidney (n?=?89) datasets, we applied regression analysis to examine associations between patient age and gene expression profiles in ccRCC tumors and normal kidney tissues. Pathway enrichment analysis was performed to identify cellular process that is affected by aging in ccRCC. Moreover, connectivity mapping analysis was used to predict age-dependent response to drug treatments.

Results

Our analysis revealed different age-dependent gene expression spectra in ccRCC and normal kidney tissues. These findings were significant and independently reproducible in both datasets examined. Age up-regulated genes, showing higher expression in older patients, were significantly enriched (false discovery rate <0.05) in normal tissues for pathways associated with immune response and extracellular matrix organization, whereas age up-regulated genes in tumors were enriched for metabolism and oxidation pathways. Strikingly, age down-regulated genes in normal cells were also enriched for metabolism and oxidation, while those in tumors were enriched for extracellular matrix organization. Further in silico analysis of potential drug targets predicted preferential efficacy of Phosphoinositide 3-kinase inhibitor or immunotherapy in association with age.

Conclusion

We report on previously unrecognized associations between age and molecular underpinnings of RCC, including age-associated expression of genes implicated in RCC development or treatment.  相似文献   
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Chest radiographs of 43 consecutive diabetic patients were evaluated with a view to determine their role as a routine investigation of patients with diabetes mellitus. 22 (51.2%) patients had normal chest radiographs. The remaining 21 patients had 61 abnormalities found in their chest radiographs. 26 (42.6%) of these were significant abnormalities while 35 (57.4%) were non-significant. Of the former, 42.3% were due to cardiomegaly while in the latter group, aortic unfolding was the main finding. Radiological abnormalities were more commonly observed in patients aged 40 years and over, than in those below, with a ratio of 3:1. Chest radiographs corroborated clinical diagnosis in 19 of the 21 cases in whom abnormalities were observed. This study shows that routine chest radiograph in diabetic patients is useful in those with clinical symptoms and in older diabetics above the age of 40 years.  相似文献   
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Treatment of metronidazole-resistant Trichomonas vaginalis infection is complicated by the lack of an effective alternative therapeutic regimen. Data on the susceptibility of the organism to metronidazole and other nitroimidazoles are important in managing intractable cases. A case of trichomonal vaginitis with true resistance to metronidazole that responded to treatment with tinidazole is reported.  相似文献   
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Fine needle aspiration cytology is a safe diagnostic technique for breast cancer and can identify certain benign lesions, which can be excised without affecting surrounding tissue. The combination of experienced operator and cytologist can yield high sensitivity and specificity, together with important prognostic information.  相似文献   
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Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery, and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions.  相似文献   
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The routine chest radiographs of 178 psychiatric patients were reviewed. 67 patients had abnormalities found on their chest radiographs. 22 (32.8 pc) of these were significant abnormalities while 45 (67.2 pc) were non-significant. There was no significant abnormality detected on the chest radiographs of any patient in whom abnormality had not been suspected clinically. No significant abnormality was found in patients below the age of 40 years. This study suggests that chest radiography should be performed only on psychiatric patients who are above the age of 40 years and especially those who have clinical evidence of chest disease.  相似文献   
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