Rigidified and Hydrophilic DOTA-like Lanthanoid Ligands: Design, Synthesis, and Dynamic Properties.

Limiting the dynamics of paramagnetic tags is crucial for the accuracy of the structural information derived from paramagnetic nuclear magnetic resonance (NMR) experiments. A hydrophilic rigid 2,2',2″,2‴-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA)-like lanthanoid complex was designed and synthesized following a strategy that allows the incorporation of two sets of two adjacent substituents. This resulted in a C2 symmetric hydrophilic and rigid macrocyclic ring, featuring four chiral hydroxyl-methylene substituents. NMR spectroscopy was used to investigate the conformational dynamics of the novel macrocycle upon complexation with europium and compared to DOTA and its derivatives. The twisted square antiprismatic and square antiprismatic conformers coexist, but the former is favored, which is different from DOTA. Two-dimensional 1H exchange spectroscopy shows that ring flipping of the cyclen-ring is suppressed due to the presence of the four chiral equatorial hydroxyl-methylene substituents at proximate positions. The reorientation of the pendant arms causes conformational exchange between two conformers. The reorientation of the coordination arms is slower when the ring flipping is suppressed. This indicates that these complexes are suitable scaffolds to develop rigid probes for paramagnetic NMR of proteins. Due to their hydrophilic nature, it is anticipated that they are less likely to cause protein precipitation than their more hydrophobic counterparts.

Phase I to II study of pleurectomy/decortication and intraoperative intracavitary hyperthermic cisplatin lavage for mesothelioma.

PURPOSE: To evaluate morbidity, mortality, maximum-tolerated dose (MTD), and outcome of intraoperative intracavitary hyperthermic cisplatin lavage in patients undergoing pleurectomy for malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Sixty-one patients were prospectively registered. Forty-four resectable patients with MPM underwent pleurectomy, followed by a 1-hour lavage of the resection cavity with dose-escalated cisplatin (50, 100, 150, 175, 200, 225, and 250 mg/m2) at 42 degrees C and then intravenous sodium thiosulfate (16 g/m2 over 6 hours). Survival estimates were compared using the log-rank test and proportional hazards regression. RESULTS: Median age was 71 years (range, 50 to 82 years). Twenty-four patients had epithelial tumors, and 20 had sarcomatous or mixed histology. Postoperative mortality was 11% (five of 44 patients). Dose-limiting renal toxicity occurred at 250 mg/m2, establishing the MTD at 225 mg/m2. Other morbidity included atrial fibrillation (14 of 44 patients, 32%) and deep venous thrombosis (four of 44 patients, 9%). Median survival time of all registered patients was 9 months, and the median survival time of resected patients was 13 months. Survival estimates differed significantly for resectable patients exposed to low doses (50 to 150 mg/m2; n = 9; median, 6 months) versus high doses (175 to 250 mg/m2; n = 35; median, 18 months) of hyperthermic cisplatin (P = .0019); recurrence-free interval also differed significantly (4 v 9 months, respectively; P < .0001). Low dose level (relative risk = 3.418) and nonepithelial histology (relative risk = 2.336) were independent risk factors for poor survival. Twenty patients with epithelial tumors who underwent high-dose cisplatin lavage had a 26-month median survival time. CONCLUSION: Pleurectomy and high-dose intraoperative intracavitary hyperthermic cisplatin lavage is feasible in this patient population with restricted surgical options. An apparent dose-related survival benefit warrants further study.

Early results of a comprehensive operative and perfusion strategy to attenuate the incidence of adverse neurological outcomes in on-pump coronary artery bypass grafting (CABG) patients.

Adverse neurological events, both focal (Type I) and non-focal (Type II), have been appreciated in postoperative on-pump coronary artery bypass grafting (CABG) patients for many years. Advanced age is a significant risk factor for adverse neurological events following CABG surgery. With full knowledge that our elderly population of patients was at high risk for these untoward neurological events, we adopted a comprehensive operative and perfusion strategy in an attempt to attenuate the incidence of these complications. Our strategy included efforts to minimise the number of emboli generated during the operation, avoid cerebral hypoperfusion, and attenuate the systemic inflammatory response. From 15 August 2002 to 31 December 2005, we performed 355 on-pump CABG operations. The incidence of Type I focal injury was 0/355 (0%), the incidence of Type II non-focal injury was 9/355 (2.5%), and postoperative mortality was 2/355 (0.6%). These results compared favorably to the results predicted by the Society of Thoracic Surgeons' (STS) model, and may suggest efficacy.