The signal transducer and activator of transcription 6 (STAT-6) mediates Th2 inflammation and tissue damage in a murine model of peanut-induced food allergy

Introduction: Food allergies are inflammatory conditions mediated by Th2 and probably STAT-6 dependent immune responses. Objective and design: Here we investigated the role of Signal Transducer and Activator of Transcription 6 (STAT-6) in development of inflammation in peanut allergy. Methods: To induce food allergy, wild-type (WT) and mice deficient for STAT-6 (Stat6-/-) were sensitized with peanut proteins and challenged with peanut seeds. Results: WT animals lost weight and refused the peanut diet, in contrast to Stat6-/- mice, which had a better maintenance of body weight and more regular seeds' consumption. The augmented peanut-specific IgG, IgG1 and IgE in the allergic WT was abolished in Stat6-/- animals that also presented increased IgG2a. There was an overall reduction in the gut mediators in the absence of STAT-6, including those related to inflammatory and Th2 responses, in contrast to a rising counter regulatory and Th1 reaction in Stat-6-/- mice. These animals had IFN-γ and IL-10 similar to WT after the four-week challenge. Most interestingly, Stat-6-/- mice had no intestinal damage, in contrast to WT animals, which had inflammatory infiltrate, tissue destruction, epithelial exulceration, edema, congestion and loss of villous architecture in the small gut segments. Conclusions: STAT-6 plays an important role in the establishment of the Th2 inflammatory responses and intestinal damage in peanut allergy

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Detection of Restenosis After Percutaneous Transluminal Coronary Angioplasty by an Angiographic Score.

BACKGROUND: Restenosis, or ÒAchilles heelÓ of balloon angioplasty, remains in a range near 30% and cannot be predicted with certainty. To find adequate methods for its foresight is a challenge. OBJECTIVES: To determine risk factors and an angiographic score to predict the appearance of restenosis after one-site percutaneous transluminal coronary angioplasty (PTCA). METHODS: We restudied prospectively 315 (239 men, 76 women, age range from 29 to 78, 53.6 +/- 9.5 years) of 360 patients who underwent PTCA to a native coronary artery. The study didnÕt include patients with left main disease, total occlusion, side-branch involvement, ostial stenosis, acute phase of myocardial infarction or those who repeat PTCA. Two-hundred twenty-eight patients underwent PTCA of the left anterior descending artery, 56 of the right coronary artery and 31 of the left circumflex artery. RESULTS: Restenosis, defined as a luminal renarrowing > 50% at follow-up, was present in 82 (26%) patients between 1 and 8 months after the procedure. Univariate and multivariate analysis revealed four vascular factors related to restenosis (p < 0.05): a) lesion length and; b) irregularity of the lesion borders before PTCA; c) perivascular and/or endovascular haziness and; d) intensity of residual stenosis after PTCA. To construct the score, a zero was given to a lesion length < 8 mm; to smooth lesion borders; to residual stenosis up to 20%; and to absence of haziness after PTCA. A one was given to a lesion length between 8 and 10 mm; and to a lesion with irregular borders. A two was given to a lesion length > 10 mm. A three was given to a residual stenosis > 20%; and to the presence of haziness after PTCA. The sum of all terms was considered the final score. So, it could oscillate from 0 to 9. Calculated score from 0 to > 5 showed respective restenosis rates of (%): 5.2; 15.1; 24.0; 39.4; 44.8; 60.8; and 84.2. The calculated correlation coefficient (0.98) among the scored values and the correspondent restenosis rates was highly significant (p < 0.001). CONCLUSIONS: It is concluded that restenosis is primarily a multifactorial problem based on vascular factors and may be predicted with a high degree of probability by the proposed score.