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991.

Background/Aims

We examined whether the insertion time for colonoscopies performed after left-sided resection was different in patients with a colostomy from that in patients without a colostomy and identified factors that could impact colonoscopy performance.

Methods

We included consecutive patients who underwent colonoscopy between July 2005 and March 2011 after left-sided colorectal resection for colorectal cancer. We classified surgical methods according to the presence or absence of a colostomy and evaluated colonoscope insertion time retrospectively. Furthermore, we analyzed factors that might affect insertion time.

Results

A total of 1,041 patients underwent colonoscopy after left-sided colorectal resection during the study period. The colonoscopy completion rate was 98.6?%, and the mean insertion time was 6.1?±?4.6?min (median 4.7?min, range 0.3?C35.8?min). A shorter resection length of colon, the presence of a colostomy, and a lower endoscopist case volume were found to be independent factors associated with prolonged insertion time in patients with left-sided colorectal resection. Among experienced colonoscopists, no colonoscopy-associated or clinical factors were found to affect insertion time. However, a shorter resection length of colon, the presence of a colostomy, and poor bowel preparation were associated with prolonged insertion time among inexperienced endoscopists.

Conclusions

We identified three factors that affect colonoscope insertion time after left-sided colorectal resection, including the presence of a colostomy. Inexperienced endoscopists were much more affected by the presence of a colostomy after left-sided colorectal resection. These findings have implications for the practice and teaching of colonoscopy after left-sided colorectal resection.  相似文献   
992.
993.

Background  

In ulcerative colitis (UC), reduction of inflammation may represent a key mechanism in UC therapy, and anti-inflammatory agents would be good candidates for preventing UC. Kaempferol, a natural flavonoid, is believed to have anti-inflammatory activities and has been shown to be potentially immune-modulatory.  相似文献   
994.

Background

Deguelin, a naturally occurring rotenoid, is known to be an Akt inhibitor and to have an anti-tumor effect on several cancers.

Aims

This study was performed to elucidate the effect of deguelin on apoptotic pathways related to NF-κB signaling in colon cancer cells and on the anti-tumor effect in colon cancer xenograft mice.

Methods

We studied COLO 205 and HCT116 cells in the presence or absence of deguelin. NF-κB signaling was examined by real-time RT-PCR for interleukin (IL)-8, by Western blotting for IκB phosphorylation/degradation, and by the electrophoretic mobility shift assay. Cell death was determined by the MTT assay, and apoptosis by Annexin V-FITC staining and caspase-3 activity. We also assessed the expression of antiapoptotic and proapoptotic factors by use of RT-PCR. In colon cancer xenograft mice, we evaluated the effect of deguelin on inoculated tumor growth, and apoptotic index was measured by the in vivo TUNEL assay.

Results

Deguelin significantly inhibited IL-8 gene expression, IκB phosphorylation/degradation, and DNA binding activity of NF-κB in colon cancer cells. Deguelin induced cell death and apoptosis in colon cancer cells in a dose and time-dependent manner. Deguelin down-regulated expression of NF-κB-mediated antiapoptotic factors such as cFLIP, Bcl-2, and Bcl-XL. In the colon cancer xenograft model, the volume of the tumor treated with deguelin was significantly lower than that of the control, and the apoptotic index for deguelin-treated mice was much higher.

Conclusion

Deguelin might be a potential therapeutic agent for treatment of colorectal cancer.  相似文献   
995.
The neurochemical alterations in the entorhinal cortex have not yet been measured, even though the entorhinal cortex is the earliest involved brain region in aMCI. In this study, we investigated whether brain regions including the entorhinal cortex would show early involvement of neurochemical abnormalities in aMCI, and whether magnetic resonance spectroscopy (MRS) abnormalities might be a predictive marker of conversion of aMCI to Alzheimer's disease (AD). MRS was performed on 13 aMCI patients and 11 patients with no cognitive impairment (NCI). Localizing voxels were placed within the entorhinal cortex, hippocampus, posterior cingulate gyrus, and occipital white matter in the dominant hemisphere. N-acetyl aspartate/creatinine (NAA/Cr) ratios in the entorhinal cortex were significantly lower in aMCI patients than in NCI subjects. After a three-year follow-up, seven aMCI patients converted to AD and six remained stable. Baseline NAA/Cr ratios of entorhinal cortex were decreased in converters, compared to NCI. Our study suggested the entorhinal cortex is the earliest site that is subject to neurochemical alteration in aMCI patients, and baseline MRS metabolite ratios in the entorhinal cortex can be a marker for predicting conversion of aMCI to AD.  相似文献   
996.
997.
The aim of this study was to investigate the relation between intravascular ultrasound (IVUS) findings and the no-reflow phenomenon and long-term outcome after percutaneous coronary intervention (PCI) of saphenous vein graft (SVG) lesions. No reflow was defined as Thrombolysis In Myocardial Infarction grade 0, 1, or 2 flow after PCI. Of 311 patients who underwent IVUS before and after stenting, no reflow was observed in 39 patients (13%). Degenerated SVG (62% vs 36%, p = 0.002), IVUS-detected intraluminal mass (82% vs 43%, p <0.001), culprit lesion multiple plaque ruptures (23% vs 6%, p <0.001), and tissue prolapse (51% vs 35%, p = 0.043) were observed more frequently in patients with no reflow. In multivariate logistic regression analysis, an intraluminal mass (odds ratio [OR] 4.84, 95% confidence interval [CI] 1.98 to 10.49, p = 0.001), culprit lesion multiple plaque ruptures (OR 3.46, 95% CI 1.46 to 8.41, p = 0.014), and degenerated SVGs (OR 3.17, 95% CI 1.17 to 6.56, p = 0.024) were the independent predictors of no reflow after PCI. At 5-year clinical follow-up, rates of death (14, 36%, vs 55, 20%, p = 0.036) and myocardial infarction (13, 33%, vs 52, 19%, p = 0.039) were significantly higher in the no-reflow group. However, rate of target vessel revascularization was not significantly different between the 2 groups (15, 38%, vs 90, 33%, p = 0.3). IVUS-detected intraluminal mass, multiple plaque ruptures, and degenerated SVGs were associated with no reflow in SVG lesions after PCI. In conclusion, no reflow was associated with poor long-term clinical outcomes after PCI for SVG lesions.  相似文献   
998.
The University of Washington Quality of Life (UW-QOL) questionnaire is often used to assess health-related quality of life (HRQOL) of head and neck cancer patients. The aim of this study was to translate the UW-QOL version 4 into the Korean language and to carry out an initial validation study. A recognized methodology for translation of questionnaires was used. The validation study used the final Korean version between March and September 2009. Adult patients were recruited, with a confirmed diagnosis of head and neck cancer, therapy completed and disease-free for at least 1 year. The UW-QOL was successfully translated into Korean. 56 patients completed Korean versions of UW-QOL, the Beck Depression Inventory and the World Health Organization Quality of Life-BREF and various expected correlations were confirmed first between the two UW-QOL subscales (Spearman 0.54 p<0.001) and then of these subscales with the other concurrent measures. Lower (worse) UW-QOL scores were seen for later stage patients in all 12 domains. The Korean version of UW-QOL is ready for use in the assessment of HRQOL for Korean patients. Validation work needs to be continued to further establish psychometric properties of the questionnaire for use in this population.  相似文献   
999.
1000.
Using ex vivo human tooth, the authors demonstrated that dental pulp stromal cells that survive after placement of composite, mineral trioxide aggregate, and glass ionomer are weaker since they undergo synergistic cell death when exposed to 2-hydroxyethylmethacrylate. DPSCs extracted from teeth that were restored with the combination of composite or MTA or GI with N-acetyl cysteine were protectedfrom cell death. Therefore, application of NAC may protect the DPSCs from adverse effects after tooth restoration.  相似文献   
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