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Andressa A.F.L. Maciel Reinaldo B. Ori Manuel B. Braga-Neto Andra B. Braga Eunice B. Carvalho Herene B.M. Lucena Gerly A.C. Brito Richard L. Guerrant Aldo A.M. Lima 《Toxicon》2007,50(8):1027-1040
Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage. 相似文献
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The aims of this research are to (1) present the French version of the Patient Generated Index (PGI, [17]), (2) test its psychometric characteristics and (3) examine the tool’s practical limitations. To achieve those goals, we conducted two studies. The first was a qualitative study of 18 participants who indicated their difficulties and expressed other comments concerning the completion of an initial back translation of the PGI. The second study tested the psychometric qualities of the adapted and revised back translation of the PGI with 97 cancer patients. To assess criterion validity, they also completed the Quality of Life Questionnaire C30 (QLQ-C30), Profile of Mood States (POMS) and Satisfaction With Life Scale (SWLS). The results indicate that PGI has good sensitivity, validity and test-retest stability. Test-retest reliability, nevertheless, must be improved. 相似文献
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F. Hampton Roy MD 《Annals of Ophthalmology》2006,38(1):35-38
A red eye is a cardinal sign of ocular inflammation. Most cases are benign and can be managed by the primary care provider.
The key is recognizing cases requiring ophthalmological consultation by differentiating between ciliary and conjunctival injection.
Ciliary injection indicates inflammation of the cornea, iris, or ciliary body, whereas conjunctival injection mainly affects
the posterior conjunctival blood vessels.
The author has stated that he does not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. The author also does not discuss the use of off-label products, which includes
unlabeled, unapproved, or investigative products or devices. 相似文献
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