Background-Experience with non-antigenic galactose α1,3 galactose (αGal) polymers and development of αGal deficient pigs has reduced or eliminated the significance of this antigen in xenograft rejection. Despite these advances, delayed xenograft rejection (DXR) continues to occur most likely due to antibody responses to non-Gal endothelial cell (EC) antigens.
Significant prolongation in xenograft survival is achieved by improved immunosuppression. These results suggest that ongoing immune responses remain the major stimulus for DXR.
OBJECTIVES: Atrial tachyarrhythmias occur in up to 25% of patients after major thoracic surgery. We examined risk factors for newonset atrial fibrillation (AF) following oesophagectomy in an attempt to guide prophylactic use of anti-arrhythmic strategies. METHODS: Data were extracted from a database of patients who underwent oesophagectomy between 1991 and 2009. Patients with pre-operative arrhythmias were excluded leaving 997 patients for further analysis. Univariate and multivariate logistic regression analyses were performed to identify factors predicting AF, and receiver operating characteristic curves were generated from a model using these predictors. Statistical significance was reflected in a P-value of <0.05. RESULTS: Patients who developed AF (n = 209; 20.96%) were older (median age 70.54 years vs. 66.9 years; P < 0.01) and included 141 males (67.4%) (P = 0.11). Patients with AF were noted to have a higher in-hospital mortality rate (n = 17; 8.1% vs. n = 34; 4.8%) (P = 0.04) and a longer stay in hospital (14 days vs. 12 days; P < 0.01). Multivariate analysis identified advanced age and neo-adjuvant chemotherapy to be independent predictors of the risk of developing AF. Assessment of discriminative ability of a predictive model revealed a cstatistic of just 0.62. CONCLUSIONS: Despite the identification of age and neo-adjuvant chemotherapy as predictors of AF, the moderate discriminative ability of predictive modelling does not support the use of prophylactic anti-arrhythmic drugs. However, the high incidence of AF after major thoracic surgery makes it necessary to understand its underlying mechanisms better before prophylactic strategies are considered.
These findings show that lymphocytes are efficiently stimulated by PAEC antigens and can mediate direct tissue destruction. These studies (1) provide an insight into the potential of cellular-mediated cardiac Xg rejection, (2) show for the first time the induction of cytotoxic pig-specific CD4+CD28- lymphocytes and (3) provide a rational basis for determining different modes of immunosuppression to treat Xg rejection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.