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Narabayashi K Murano M Egashira Y Noda S Kawakami K Ishida K Kuramoto T Abe Y Inoue T Murano N Tokioka S Takii M Umegaki E Higuchi K 《Digestion》2012,85(2):136-140
Collagenous colitis (CC) is a well-known cause of chronic non-bloody diarrhea, especially in elderly women. CC is characterized histopathologically by an increase in the thickness of the subepithelial collagen layer to at least 10 μm, epithelial damage, and chronic inflammation of the lamina propria. Generally, the colonic mucosa in CC is macroscopically normal, although minor, non-specific abnormalities may be found. Due to the recent advancement of endoscopic and diagnostic technologies, however, microscopic mucosal abnormalities and specific longitudinal linear lacerations of the mucosa characteristic of CC have been identified. The association of CC with non-steroidal anti-inflammatory drugs and proton pump inhibitors has also been reported. Since definitive diagnosis of CC has to rely on pathologically documented collagen bands and mononuclear infiltration, the efficiency and precision of colonic biopsy need to be improved. Of the 29 CC patients that we have encountered at our institution, it was in 15 of 29 cases that the endoscopic finding that we performed a biopsy on was apparent. Our comparison of the endoscopic and histopathological findings of CC in the 15 patients showed that the mucosa frequently appeared coarse and nodular on the surface of the mucosa, which was also significantly thicker in collagen bands, demonstrating a strong correlation between collagen band formation and CC. Also, the coarse and nodular surface of the mucosa was most frequently seen affecting the proximal colon. The results suggest that endoscopic observation and biopsy of the proximal colon, where a coarse and nodular surface of the mucosa is often found, may be useful for confirmation of the diagnosis in patients with suspected CC. 相似文献
954.
H Okada M Takemoto Y Kawahara J Nasu R Takenaka S Kawano M Inoue K Ichimura T Tanaka K Shinagawa T Yoshino K Yamamoto 《Digestion》2012,86(3):179-186
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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Structures of KIX domain of CBP in complex with two FOXO3a transactivation domains reveal promiscuity and plasticity in coactivator recruitment 总被引:1,自引:0,他引:1
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Fujita M Fujita Y Iuchi S Yamada K Kobayashi Y Urano K Kobayashi M Yamaguchi-Shinozaki K Shinozaki K 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(16):6343-6347
Polyamines (PAs) are ubiquitous, polycationic compounds that are essential for the growth and survival of all organisms. Although the PA-uptake system plays a key role in mammalian cancer and in plant survival, the underlying molecular mechanisms are not well understood. Here, we identified an Arabidopsis L-type amino acid transporter (LAT) family transporter, named RMV1 (resistant to methyl viologen 1), responsible for uptake of PA and its analog paraquat (PQ). The natural variation in PQ tolerance was determined in 22 Arabidopsis thaliana accessions based on the polymorphic variation of RMV1. An RMV1-GFP fusion protein localized to the plasma membrane in transformed cells. The Arabidopsis rmv1 mutant was highly resistant to PQ because of the reduction of PQ uptake activity. Uptake studies indicated that RMV1 mediates proton gradient-driven PQ transport. RMV1 overexpressing plants were hypersensitive to PA and PQ and showed elevated PA/PQ uptake activity, supporting the notion that PQ enters plant cells via a carrier system that inherently functions in PA transport. Furthermore, we demonstrated that polymorphic variation in RMV1 controls PA/PQ uptake activity. Our identification of a molecular entity for PA/PQ uptake and sensitivity provides an important clue for our understanding of the mechanism and biological significance of PA uptake. 相似文献
959.
Benjamin Lin William R. Holmes C. Joanne Wang Tasuku Ueno Andrew Harwell Leah Edelstein-Keshet Takanari Inoue Andre Levchenko 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(52):E3668
Migrating cells possess intracellular gradients of active Rho GTPases, which serve as central hubs in transducing signals from extracellular receptors to cytoskeletal and adhesive machinery. However, it is unknown whether shallow exogenously induced intracellular gradients of Rho GTPases are sufficient to drive cell polarity and motility. Here, we use microfluidic control to generate gradients of a small molecule and thereby directly induce linear gradients of active, endogenous Rac without activation of chemotactic receptors. Gradients as low as 15% were sufficient not only to trigger cell migration up the chemical gradient but to induce both cell polarization and repolarization. Cellular response times were inversely proportional to the steepness of Rac inducer gradient in agreement with a mathematical model, suggesting a function for chemoattractant gradient amplification upstream of Rac. Increases in activated Rac levels beyond a well-defined threshold augmented polarization and decreased sensitivity to the imposed gradient. The threshold was governed by initial cell polarity and PI3K activity, supporting a role for both in defining responsiveness to Rac activation. Our results reveal that Rac can serve as a starting point in defining cell polarity. Furthermore, our methodology may serve as a template to investigate processes regulated by intracellular signaling gradients. 相似文献
960.