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51.
The accumulation of uremic toxins is involved in the progression of CKD. Various uremic toxins are derived from gut microbiota, and an imbalance of gut microbiota or dysbiosis is related to renal failure. However, the pathophysiologic mechanisms underlying the relationship between the gut microbiota and renal failure are still obscure. Using an adenine-induced renal failure mouse model, we evaluated the effects of the ClC-2 chloride channel activator lubiprostone (commonly used for the treatment of constipation) on CKD. Oral administration of lubiprostone (500 µg/kg per day) changed the fecal and intestinal properties in mice with renal failure. Additionally, lubiprostone treatment reduced the elevated BUN and protected against tubulointerstitial damage, renal fibrosis, and inflammation. Gut microbiome analysis of 16S rRNA genes in the renal failure mice showed that lubiprostone treatment altered their microbial composition, especially the recovery of the levels of the Lactobacillaceae family and Prevotella genus, which were significantly reduced in the renal failure mice. Furthermore, capillary electrophoresis–mass spectrometry-based metabolome analysis showed that lubiprostone treatment decreased the plasma level of uremic toxins, such as indoxyl sulfate and hippurate, which are derived from gut microbiota, and a more recently discovered uremic toxin, trans-aconitate. These results suggest that lubiprostone ameliorates the progression of CKD and the accumulation of uremic toxins by improving the gut microbiota and intestinal environment.  相似文献   
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BACKGROUND & AIMS: Aberrant crypt foci, precursors of colonic adenoma, are frequently positive for glutathione-S-transferase P1-1. Because deoxycholic acid is an apoptosis-inducing xenobiotic in the colon, we examined the possibility that aberrant crypt foci, through the cytoprotecting function of glutathione-S-transferase P1-1, resist deoxycholic acid-induced apoptosis, thereby surviving to become adenomas and subsequently cancer. METHODS: Glutathione-S-transferase P1-1 or cyclooxygenase-2 expression and the percentage of apoptotic cells in aberrant crypt foci were examined by immunohistochemistry and by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, respectively. Glutathione-S-transferase P1-1 was transfected into colon cancer cells (M7609) and human lung fibroblasts, and deoxycholic acid-induced apoptosis was evaluated by a dye-uptake assay and flow cytometry. Binding of deoxycholic acid to glutathione-S-transferase P1-1 was analyzed by circular dichroism and immunoprecipitation. Caspase activities were determined by colorimetric protease assay, and sulindac binding to glutathione-S-transferase P1-1 was determined by inhibition assay of glutathione-S-transferase P1-1 activity. RESULTS: Aberrant crypt foci showed positive immunostaining for glutathione-S-transferase P1-1 but negative staining for cyclooxygenase-2. The percentage of apoptotic cells in aberrant crypt foci was significantly lower than in healthy epithelium, and the difference became more apparent with deoxycholic acid treatment. The impaired sensitivity of aberrant crypt foci to deoxycholic acid was restored by the glutathione-S-transferase P1-1-specific inhibitor gamma-glutamyl-S-(benzyl)cysteinyl-R-phenylglycine diethylester. By transfection of glutathione-S-transferase P1-1, M7609 cells became more resistant to deoxycholic acid-induced apoptosis than mock transfectants. Direct binding of glutathione-S-transferase P1-1 to deoxycholic acid was proven by circular dichroism and by immunoprecipitation. The aberrant crypt foci in adenoma patients treated with sulindac, which was shown to bind to glutathione-S-transferase P1-1, underwent apoptosis in 4 days and mostly regressed in 2-3 months. CONCLUSIONS: Glutathione-S-transferase P1-1 protects aberrant crypt foci from deoxycholic acid-induced apoptosis and may play a pivotal role in early colon carcinogenesis.  相似文献   
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Background

Perihilar cholangiocarcinoma (PHC) often requires extensive surgery which is associated with substantial morbidity and mortality. This study aimed to compare an Eastern and Western PHC cohort in terms of patient characteristics, treatment strategies and outcomes including a propensity score matched analysis.

Methods

All consecutive patients who underwent combined biliary and liver resection for PHC between 2005 and 2016 at two Western and one Eastern center were included. The overall perioperative and long-term outcomes of the cohorts were compared and a propensity score matched analysis was performed to compare perioperative outcomes.

Results

A total of 210 Western patients were compared to 164 Eastern patients. Western patients had inferior survival compared to the East (hazard-ratio 1.72 (1-23-2.40) P < 0.001) corrected for age, ASA score, tumor stage and margin status. After propensity score matching, liver failure rate, morbidity, and mortality were similar. There was more biliary leakage (38% versus 13%, p = 0.015) in the West.

Conclusion

There were major differences in patient characteristics, treatment strategies, perioperative outcomes and survival between Eastern and Western PHC cohorts. Future studies should focus whether these findings are due to the differences in the treatment or the disease itself.  相似文献   
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Guided bronchoscopy has been found to be useful for the diagnosis of solid peripheral pulmonary lesions (PPLs) but more evidence on ground glass opacities (GGOs), especially those without a solid component, are lacking. A 69-year-old male, asymptomatic, heavy smoker was referred to our department for non-surgical diagnosis of a focal pure GGO in the right upper lobe that was found incidentally on computed tomography (CT). Transbronchial biopsy (TBB) with the aide of endobronchial ultrasound with a guide sheath (EBUS-GS), virtual bronchoscopic navigation (VBN), and fluoroscopy was performed for sampling. There were no complications after the procedure. The diagnosis of adenocarcinoma with lepidic growth pattern was established from the fourth and fifth TBB specimens and was confirmed on subsequent surgical resection. Image-guided bronchoscopy with TBB was successful for the diagnosis of a pure GGO. Use of a larger biopsy device may be helpful for the histopathologic diagnosis of lung adenocarcinoma with lepidic growth.  相似文献   
57.
18O‐labeled water (Water‐18O) is a widely used starting material of 18F‐labeled diagnostic agents in positron emission tomography (PET). Conventionally, Water‐18O has been separated from other stable oxygen isotope species (16O, 17O) by water distillation or nitric oxide distillation. However, conventional methods are costly and may have safety issues. In 2004, we developed the first unit of our novel oxygen isotope separation process by cryogenic oxygen distillation to overcome these issues. To meet the needs of the market, we built a second unit in 2013 and a third in 2016. We are now operating three commercially viable separation units with a total capacity of 600 kg of Water‐18O per year.  相似文献   
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Background/Aims: Few studies exist on the efficacy and long-term outcome of radiation therapy (RT) for gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Methods: Twenty-two patients with stage I or stage II(1) disease were prospectively evaluated, including 14 patients without Helicobacter pylori(H. pylori) infection and 8 patients with persistent lymphoma after H. pylori eradication. RT dose was 30 Gy in daily fractions of 1.5 Gy. All patients underwent endoscopic and histological follow-up regularly. Results: The study included 22 patients with a mean age of 63 years. The t(11;18)(q21;q21) translocation occurred in 8 of the 22 cases. All patients showed complete remission without any serious toxicity. At a median follow-up evaluation 74 months (range 27-159) after completion of RT, the overall and relapse-free survival rates after 5 years were 91 and 84%, respectively. Although no patient showed local recurrence of lymphoma, distant recurrence was detected in 3 patients, all of whom were H. pylori negative; MALT lymphoma relapsed in two patients with the t(11;18)(q21;q21) translocation, and diffuse large-cell lymphoma developed in one patient without the translocation. Conclusion: RT provides excellent local control of the gastric MALT lymphoma. However, continuous follow-up is mandatory as relapse may occur in other sites.  相似文献   
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