RESUMO
Anomalous origin of the left coronary artery from the pulmonary artery is rare but causes myocardial ischemia and sudden death. A few patients with this anomaly can survive to adulthood without sufficient collateral coronary flow or surgical intervention. We present here a case of acute inferior myocardial infarction, which may occur due to thrombotic occlusion of the right coronary artery, in a 63-year-old woman with anomalous origin of the left coronary artery from the pulmonary artery, providing specific coronary angiographic findings.
RESUMO
Chitosan is a biodegradable and biocompatible polymer and is useful as a non-viral vector for gene delivery. In order to deliver pDNA/chitosan complex into macrophages expressing a mannose receptor, mannose-modified chitosan (man-chitosan) was employed. The cellular uptake of pDNA/man-chitosan complexes through mannose recognition was then observed. The pDNA/man-chitosan complexes showed no significant cytotoxicity in mouse peritoneal macrophages, while pDNA/man-PEI complexes showed strong cytotoxicity. The pDNA/man-chitosan complexes showed much higher transfection efficiency than pDNA/chitosan complexes in mouse peritoneal macrophages. Observation with a confocal laser microscope suggested differences in the cellular uptake mechanism between pDNA/chitosan complexes and pDNA/man-chitosan complexes. Mannose receptor-mediated gene transfer thus enhances the transfection efficiency of pDNA/chitosan complexes.
Assuntos
Quitosana/farmacocinética , Técnicas de Transferência de Genes , Macrófagos Peritoneais , Plasmídeos/genética , Transfecção/métodos , Animais , Células Cultivadas , Quitosana/química , DNA , Vetores Genéticos/síntese química , Lectinas Tipo C/metabolismo , Lectinas Tipo C/fisiologia , Manose , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Lectinas de Ligação a Manose/fisiologia , Camundongos , Microscopia Confocal , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/fisiologiaRESUMO
Chitosan is a useful nonviral vector for gene delivery. To make a pDNA/chitosan complex specific to hepatocytes, lactose-modified chitosan (lac-chitosan) was synthesized. When the percentage of lactose residues substituted was 8%, lac-chitosan showed excellent DNA-binding ability, good protection of DNA from nuclease, and the suppression of self-aggregation and serum-induced aggregation. Although the cellular uptake efficiency of the pDNA/lac-chitosan complex was almost the same as that of the pDNA/chitosan complex, the cell transfection efficiency of the former was greater for HepG2 cells having asialoglycoprotein receptors. Inhibitor of endocytosis such as bafilomycin A1 and nocodazole significantly reduced the transfection efficiency of the pDNA/lac-chitosan complex. Observations with a confocal laser scanning microscope indicated that the pDNA/lac-chitosan complexes traversed endocytic compartments more rapidly than the pDNA/chitosan complex. Furthermore, the pDNA/lac-chitosan complexes were delivered to the late endosome and have the advantage of delivering DNA to the perinuclear region.
