The pulse-coupled neural network (PCNN) is a neural network that has the ability to extract edges, image segments and texture information from images. Only a few changes to the PCNN parameters are necessary to effective operating on different types of data. This is an advantage over the published image segmentation algorithms which generally require information about the target before they are effective.
This paper introduces the PCNN algorithm to provide an accurate segmentation of potential masses in mammogram images to assist radiologists in making their decisions. The fuzzy histogram hyperbolization algorithm is first applied to increase the contrast of the mammogram image before reasonable segmentation. It is followed by the PCNN algorithm to extract the region of interest to arrive at the final result. To test the effectiveness of the introduces algorithm on high quality images, a set of mammogram images was chosen and obtained from the Digital Databases for Mammography Image Analysis Society (MIAS). Four measures of quantifying enhancement have been adapted in this work. Each measure is based on the statistical information obtained from the labeled region of interest and a border area surrounding it. A comparison with the fuzzy c-mean clustering algorithm has been made.
Cell surface expression of PD-1, PD-L1 and PD-L2 immune checkpoints on B and T cells obtained from patients with mantle cell lymphoma shows ambiguous results across many studies and creates obstacles for the implementation of immune checkpoint inhibitors into the therapy of mantle cell lymphoma. Using multiparameter flow cytometry we analysed surface expression of PD-1, PD-L1 and PD-L2 molecules on B and T cells of 31 newly diagnosed mantle cell lymphomas and compared it with the results of 26 newly diagnosed chronic lymphocytic leukaemias and 20 healthy volunteers. To gain insight into the age-dependent changes of surface expression of these immune checkpoints, flow cytometric subanalysis of 30 healthy volunteers of 25–93 years of age was conducted. Overall, we demonstrated weak surface expression of PD-1, PD-L1 and PD-L2 on B and T cells of mantle cell lymphoma patients (< 10 % when compared to healthy individuals). A significant age-dependent increase in the expression of PD-1 and its ligand PD-L2 was observed in healthy volunteers. Our results suggest that neither PD-1 nor its ligands represent relevant druggable targets for the therapy of mantle cell lymphoma. The observed age-dependent changes in healthy population could impact efficiency of immune checkpoint inhibitors and could be at least partly connected with increased incidence of cancer with age.