The cucurbit[7]uril (CB7) host forms rotaxane-type complexes with dumbbell-shaped, cationic guests bis(3,5-dimethoxybenzyl)-4,4'-bipyridinium (1(2+)) and bis(3,5-diethoxybenzyl)-4,4'-bipyridinium (2(2+)). The kinetics of complex formation is slower with the latter guest because of its bulkier end groups. Rotaxane formation was found to be thermodynamically more favorable and kinetically faster in D2O than in DMSO-d6 solution, which highlights the importance of hydrophobic interactions in the assembly of cucurbituril complexes.
View Article and Find Full Text PDFObjective: To evaluate the incidence, timing of diagnosis, clinical factors for adverse outcome, and role of anticoagulant, surgical therapy, or endovascular intervention for patients with blunt carotid artery injury (BCAI).
Methods: Retrospective review of the records of patients who sustained BCAI between 1987 and 1997.
Results: There were 18 men and 12 women, with an average age of 29 years.
The underlying cause and treatment of hemoptysis should be addressed promptly to avoid potentially life-threatening complications. We report on a previously healthy 11-year-old white boy who presented with acute hemoptysis. On bronchoscopy, bleeding was noted from the right upper and lower lobes.
View Article and Find Full Text PDFHemothorax and persistent thoracic bleeding is frequently an indication for thoracotomy after trauma. Unfortunately, the source of the hemorrhage is often not identified. Presently, selective arteriography and transcatheter embolization (SATE) offers a good and safe alternative to localize and control hemorrhage from arterial injuries in selected patients.
View Article and Find Full Text PDFMay-Thurner syndrome is a condition in which there is impaired venous return due to compression of the left common iliac vein by the overlying right common iliac artery. The impedance of flow occurs both by the compressive force of the artery against the vein and by resultant intraluminal web formation inside the vein. Because of the mechanical nature of the obstruction, conservative management of these patients has resulted in poor outcomes.
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