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31.
The usefulness of a covered self‐expandable metallic stent for benign esophageal stricture and perforation was well established. In case of benign disease, early stent removal was recommended within 6–8 weeks after placement. A case with severe esophageal stricture caused by incomplete stent removal 7 years after stent placement for spontaneous esophageal rupture was reported. Residual stent fragments could be removed by step‐by‐step multimodal endoscopic treatment, producing satisfactory luminal diameter of the esophagus. In particular, stent trimming with argon plasma coagulation was safe and effective strategy. The endoscopic stent removal is minimally invasive and should be attempted before surgical intervention; however, it is most important to ensure early stent removal before tissue ingrowth or overgrowth can develop.  相似文献   
32.

Background

Cardiac fibrosis is considered to be a crucial factor in the development of heart failure. Blockade of the mineralocorticoid receptor (MR) attenuated cardiac fibrosis and improved the prognosis of patients with chronic heart failure but the ligand for MR and the regulatory mechanism of MR pathway in the diseased heart are unclear. Here, we investigated whether glucocorticoids can promote cardiac fibrosis through MR in oxidative stress and the involvement of elongation factor eleven-nineteen lysine-rich leukemia (ELL), a co-activator of MR, in this pathway.

Methods and Results

The MR antagonist eplerenone attenuated corticosterone-induced collagen synthesis assessed by [3H]proline incorporation in rat neonatal cultured cardiac fibroblasts in the presence of H2O2, as an oxidative stress but not in the absence of H2O2. H2O2 increased the ELL expression levels and MR-bound ELL. ELL expression levels and MR-bound ELL were also increased in the left ventricle of heart failure model rats with significant fibrosis and enhanced oxidative stress. Eplerenone did not attenuate corticosterone-induced increase of [3H]proline incorporation in the presence of H2O2 after knockdown of ELL expression using small interfering RNA in cardiac fibroblasts.

Conclusion

Glucocorticoids can promote cardiac fibrosis via MR in oxidative stress, and oxidative stress modulates MR response to glucocorticoids through the interaction with ELL. Preventing cardiac fibrosis by modulating glucocorticoid-MR-ELL pathway may become a new therapeutic strategy for heart failure.  相似文献   
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Milk fat globule-epidermal growth factor 8 (MFG-E8), a glycoprotein secreted from various cells, enhances engulfment of apoptotic cells by forming a link between phosphatidylserine on apoptotic cells and α(v)β(3)-integrin on phagocytes. This process is essential for maintaining the host immune system under physiological conditions. Apart from this scavenging function, MFG-E8 also directly regulates a variety of cellular functions, such as attenuating inflammation and healing of injured tissues. Furthermore, recent studies have revealed that MFG-E8 has anti-inflammatory and regenerating roles during intestinal inflammation. This review highlights novel findings regarding the roles of MFG-E8 in intestinal pathophysiology as well as its therapeutic potential for gut inflammatory disorders.  相似文献   
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BackgroundThe diagnostic assessment of the level of difficulty in treating patients who need prosthodontic care is useful to establish a medico-economically efficient system with primary care dentists and prosthodontic specialists.Materials and methodsA multi-axis assessment protocol was established using the newly established treatment difficulty indices. The protocol contains Axis I: oral physiological conditions (e.g., teeth damage and/or missing teeth); Axis II: general health and sociological conditions (e.g., medical disorders); Axis III: oral health-related quality of life (OHRQOL; e.g., oral health impact profile: OHIP); and Axis IV: psychological health (e.g., mood, anxiety, somatoform disorders). A preliminary study on the test–retest consistency of the protocol was conducted to check the levels of reliability of the indices prior to a large-scale, multi-center cohort study on the validity of the protocol.ResultsThe test–retest consistency in terms of the oral physiological condition (Axis I) after data reduction was 0.63 for patients with teeth problems, 0.95 for partially edentulous patients, and 0.62 for edentulous patients. The reliability for general health and sociological conditions (Axis II), OHRQOL (Axis III), and psychological health (Axis IV) were 0.88, 0.74, and 0.61, respectively. These values reflect either “sufficient agreement” or “excellent agreement” in accordance with the criteria established by Landis and Koch (1977) [1].ConclusionThis protocol is the first multi-axis assessment scheme introduced for prosthodontic treatment with sufficient reliability. This new system is therefore expected to have a significant impact on future dental diagnostic nomenclature systems.  相似文献   
38.

Background

Dysplastic squamous epithelium is a precancerous lesion for squamous cell carcinoma. It is often present in the esophagus and head and neck region, and can be visualized as a Lugol-voiding lesion (LVL) by iodine chromoendoscopy. However, effective treatment for such dysplastic epithelia has not yet been developed.

Methods

Between March 2008 and July 2011, 40 consecutive patients with advanced esophageal squamous cell carcinoma were treated by two cycles of neoadjuvant chemotherapy (NAC) (5-fluorouracil, 800?mg/m2, d 1?C5; cisplatin, 80?mg/m2, d 1: q 21?days) at Kyoto University Hospital, and received iodine chromoendoscopy both before and after NAC. Iodine chromoendoscopy findings were divided into 4 groups: group?A, absence of LVLs; group?B, several (??10/one endoscopic view) small (??5?mm) LVLs; group?C, many (??10/one endoscopic view) small (??5?mm) LVLs; group?D, numerous irregular-shaped multiform LVLs. Group?C and D are defined as multiple LVLs. Endoscopic changes of LVLs before and after NAC were investigated retrospectively.

Results

Before NAC, 6, 12, 9, and 13 cases were classified in group?A, B, C, and D, respectively. All cases in group?A before NAC remained in group?A after NAC. Multiple LVLs (group?C and D) were significantly improved in 17 of 22 patients (77.3?%), while several small LVLs (group?B) were improved in only 4 of 12 cases (33.3?%) (p?=?0.025 by Fisher??s exact test).

Conclusions

Multiple dysplastic lesions tended to improve by chemotherapy. In contrast, there was little change in the mucosa with fewer dysplastic lesions after chemotherapy. These data show that chemotherapy has the potential to eliminate precancerous lesions.  相似文献   
39.
Background: Lipopolysaccharide (LPS) stimulates osteoclast differentiation through toll‐like receptors (TLRs) 2 and 4, and hydrogen sulfide (H2S) induces osteoclast differentiation. If H2S activates TLRs, H2S may enhance the effects of LPS on osteoclast differentiation. The purpose of the present study is to examine the combined effects of sodium hydrogen sulfide (NaHS, an H2S donor drug) and LPS on osteoclast differentiation and TLR expression in rat periodontal tissue. Methods: Twenty‐eight male Wistar rats (8 weeks old) were divided into four groups (n = 7 per group): a control (no treatment) group and three experimental groups (NaHS group, LPS group, and a combination [NaHS + LPS] group). At 1 day after topical application of NaHS and/or Porphyromonas gingivalis LPS into the gingival sulcus of first molars, the number of tartrate‐resistant acid phosphate (TRAP)‐positive osteoclasts in the periodontal tissue was counted. Expression of TLR2 and TLR4 mRNAs and proteins in the gingival was also assessed. Results: The number of TRAP‐positive osteoclasts was significantly higher in the combination group than in any other group (P <0.01). The combination group had 11.0‐fold higher TLR4 mRNA levels than the control group. TLR4 protein levels were also higher in the combination group than in the NaHS or LPS group. However, the TLR2 mRNA and protein levels were not significantly different in the combination group and the LPS group. Conclusion: In rat periodontal tissue, NaHS and LPS had an additive effect on osteoclast differentiation through activation of the TLR4 pathway but not the TLR2 pathway.  相似文献   
40.
The purpose of this study was to investigate the use of different plasticizers in soft acrylic resin materials to reduce leaching of the plasticizer and thus increase the durability of tissue conditioners. Samples were prepared containing different combinations of three types of polymer/copolymer powder and four types of plasticizer liquid (DEHM, DIBA, DAA and DINA). The dynamic viscoelasticity of each sample was measured after water immersion using a dynamic mechanical analyzer. Water absorption, solubility and weight change were also measured. A significant difference was found among the materials regarding dynamic viscoelasticity, water absorption and solubility. The samples containing P-n-BMA had the most stable G' and G' scores throughout the immersion. P-n-BMA is the most suitable powder together with DEHM as the most suitable liquid component for a tissue conditioner. These results suggest that it is possible to improve the durability of tissue conditioners by combining different polymers and plasticizers.  相似文献   
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