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991.
A case of a single coronary artery is described in a 50-year-old male, who died of asphyxia. The artery originated in the right aortic sinus and from it another artery emerged which crossed the crista supraventricularis and the interventricular septum and returned to occupy a subepicardial position in the lower half of the anterior interventricular sulcus. This partially intramyocardial artery was considered as the anterior interventricular artery. A literature survey showed only five cases with similar characteristics. The importance of this anomaly derives from the risk of damage occurring to the intramyocardial artery during a manipulation of the infundibulum of the right ventricle in a cardiac surgery or from problems of perfusion during coronary bypass procedures.  相似文献   
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Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133+ population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from ‘early’ endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis.  相似文献   
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Transporters play a vital role in both the resistance mechanisms of existing drugs and effective targeting of their replacements. Melarsoprol and diamidine compounds similar to pentamidine and furamidine are primarily taken up by trypanosomes of the genus Trypanosoma brucei through the P2 aminopurine transporter. In standardized competition experiments with [3H]adenosine, P2 transporter inhibition constants (Ki) have been determined for a diverse dataset of adenosine analogs, diamidines, Food and Drug Administration-approved compounds and analogs thereof, and custom-designed trypanocidal compounds. Computational biology has been employed to investigate compound structure diversity in relation to P2 transporter interaction. These explorations have led to models for inhibition predictions of known and novel compounds to obtain information about the molecular basis for P2 transporter inhibition. A common pharmacophore for P2 transporter inhibition has been identified along with other key structural characteristics. Our model provides insight into P2 transporter interactions with known compounds and contributes to strategies for the design of novel antiparasitic compounds. This approach offers a quantitative and predictive tool for molecular recognition by specific transporters without the need for structural or even primary sequence information of the transport protein.  相似文献   
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