Objective To compare the principles and performance of three Hough transform algorithms(standard Hough transform,gradient based Hough transform,and random Hough transform)in order to establish a suitable control basis for precise and rapid recognition of targets and acquisition of target center coordinates for craniocerebral puncture robots.Methods A simulation environment in MATLAB software was built to study and analyze image feature recognition,filtering,edge detection,cumulative voting and other processing engineering.Contour recognition and fitting of target circles were achieved in multiple scenarios before their center coordinates were obtained.The recognition and fitting performance of these algorithms was quantitatively compared.Finally,a better detection algorithm based on the actual environment of the craniocerebral puncture robot was determined.Results The standard Hough transform algorithm had the largest error between the mark circle and the target circle,and the running time of this algorithm was the longest due to large computation.The detection speed of the random Hough transform algorithm was lower than that of the gradient-based Hough transform algorithm,but the fitting accuracy was slightly better than that of the standard Hough transform algorithm.The speed and accuracy of circle fitting based on the gradient Hough transform algorithm had significant advantages over the other two.Conclusion The gradient based Hough transform algorithm is more suitable for obtaining the target center coordinates of the craniocerebral puncture robot system.

BACKGROUNDAtherosclerosis is a kind of disease with multiple risk factors, of which hyperlipidemia is a major classical risk factor resulting in its pathogenesis and development. The aim of this study was to determine the effects of short-term intensive atorvastatin (IA) therapy on vascular endothelial function and explore the possible mechanisms that may help to explain the clinical benefits from short-term intensive statin therapy.

METHODSAfter exposure to high-fat diet (HFD) for 8 weeks, the animals were, respectively, treated with IA or low-dose atorvastatin (LA) for 5 days. Blood lipids, C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide (NO), endothelin-1 (ET-1), and endothelium-dependent vasorelaxation function were, respectively, measured. mRNA and protein expression of CRP, TNF-α, IL-6, macrophage chemoattractant protein-1 (MCP-1), and 5-lipoxygenase (5-LO) were also evaluated in pericarotid adipose tissue (PCAT) and cultured adipocytes.

RESULTSHFD increased serum inflammatory factor levels; induced significant hyperlipidemia and endothelial dysfunction, including imbalance between NO and ET-1; enhanced inflammatory factors and 5-LO expression; and promoted macrophage infiltration into adipose tissue. Five-day IA therapy could significantly decrease serum inflammatory factor levels and their expression in PCAT; restore the balance between NO and ET-1; and improve endothelial function and macrophage infiltration without significant changes in blood lipids. However, all of the above were not observed in LA therapy. In vitro experiment found that lipopolysaccharide (LPS) enhanced the expression of inflammatory factors and 5-LO in cultured adipocytes, which could be attenuated by short-time (6 hours) treatment of high-dose (5 µmol/L) but not low-dose (0.5 µmol/L) atorvastatin. In addition, inhibiting 5-LO by Cinnamyl-3,4-dihydroxy-α-cyanocinnamate (CDC, a potent and direct 5-LO inhibitor) could significantly downregulate the above-mentioned gene expression in LPS-treated adipocytes.

CONCLUSIONShort-term IA therapy could significantly ameliorate endothelial dysfunction induced by HFD, which may be partly due to attenuating inflammation of PCAT through inhibiting 5-LO pathway.

Adipose Tissue ; drug effects ; immunology ; Animals ; Arachidonate 5-Lipoxygenase ; metabolism ; Atorvastatin Calcium ; Heptanoic Acids ; therapeutic use ; Hyperlipidemias ; drug therapy ; immunology ; Inflammation ; drug therapy ; immunology ; Lipid Metabolism ; drug effects ; Male ; Pyrroles ; therapeutic use ; Rabbits