Cyclic AMP prolongs graft survival by suppressing apoptosis and inflammatory gene expression in acute cardiac allograft rejection

This study was designed to investigate the effects of cAMP on immune regulation and apoptosis during acute rat cardiac allograft rejection. We found that the production of immune markers such as inflammatory cytokines (IL-1beta, IL-6, and TNF-alpha), iNOS expression, and nitric oxide (NO) production, was significantly increased in the blood and transplanted hearts of allograft recipients, but not of isograft controls. These increases were effectively suppressed by the administration of the membrane permeable cAMP analog dibutyryl cAMP (db-cAMP). Administration of db-cAMP reduced allograft-induced elevation of several biochemical markers, such as adhesion molecule expression, iron-nitrosyl complex formation, caspase-3 activation, and apoptotic DNA fragmentation in an animal model. Furthermore, treatment of allograft recipients with db-cAMP prolonged median graft survival to 11 days compared with a median graft survival time of 8 days in saline-treated allograft recipients. These results suggest that db-cAMP exerts a beneficial effect on murine cardiac allograft survival by modulating allogeneic immune response and cytotoxicity.

Predictive Factors for Conversion of Laparoscopic to Open Cholecystectomy

PURPOSE: Laparoscopic cholecystectomy (LC) has replaced open cholecystectomy (OC) for the treatment of gallbladder disease. However certain cases still require conversion to open procedures. Identifying these patients at the risk of conversion remains difficult. This study evaluated risk factors that may predict conversion from a laparoscopic to an open procedure. METHODS: From January 1994 to December 2004, a total of 582 laparoscopic cholecystectomies were performed at Seoul Medical Center. A retrospective analyses of clinical parameters including patient demographics, clinical histories, laboratory data, ultrasound results, intraoperative details and postoperative pathologic findings were performed. RESULTS: A total of 30 patients (5.2%) had their cholecystectomies converted to an open procedure. Causes for conversion were inability to correctly identify the anatomy of surgical field due to adhesion and inflammation (56.7%), bile duct injury (13.3%), bleeding (13.3%) and others (16.7%). Univariate analysis showed that ASA (the classification of American Society of Anesthesiologists, p = 0.034), previous abdominal operation history (p = 0.008), RUQ tenderness(right upper quadrant tenderness, p = 0.002), acute cholecystitis (p < 0.001) and time elapsing between diagnosis and operation (p = 0.013) to be risk factors. Multivariate analysis revealed that acute cholecystitis (4.2 greater odds ratio [OR] of conversion, p = 0.002) and previous abdominal operation history (3.6 greater odds ratio [OR] of conversion, p = 0.003) were positive independent predictive factors for conversion to open cholecystectomy. CONCLUSION: Although laparoscopic cholecystectomy is a safe and beneficial procedure in the management of patients with gallbladder disease, there are still many chances of conversion of laparoscopic to open cholecystectomy. In this study, patients with acute cholecystitis and previous abdominal operation histories were more likely to require conversion to an open procedure. These two positive independent predictive factors can help operators to make early decision and to counsel patients undergoing laparoscopic cholecystectomy with regards to the posibility of conversion to an open procedure.