Cellular profile of the peritumoral inflammatory infiltrate in squamous cells carcinoma of oral mucosa: Correlation with the expression of Ki67 and histologic grading

<p>Abstract</p> <p>Background</p> <p>Squamous cells carcinoma is the most important malignant tumor with primary site in the oral cavity and, given the great exposure of mucosa and lips to the etiologic factors of this neoplasm, its incidence is high. Investigation of the prognostic determinants is significant for the expectations of treatment proposal and cure of the patient. The local immune response represented by peritumoral inflammatory infiltrate is a possible prognostic factor.</p> <p>Methods</p> <p>In this study, oral mucosa samples of squamous cells carcinoma were analyzed, separated according to their histological classification as well as the phenotypical profile of the cells comprising the peritumoral inflammatory infiltrate was investigated by immunohistochemical method, in addiction, the cell proliferation index via protein Ki67 expression was determinated.</p> <p>Results</p> <p>The T lymphocytes made up most of this inflammatory infiltrate, and among these cells, there was a predominance of T CD8 lymphocytes relative to the T CD4 lymphocytes. The B lymhocytes were the second most visualized leucocyte cell type followed by macrophages and neutrophils. The immunohistochemical assessment of Ki-67 positive cells revealed a greater expression of this protein in samples of undifferentiated squamous cells carcinoma.</p> <p>Conclusion</p> <p>The results suggest that the cellular immune response is the main defense mechanism in squamous cells carcinoma of oral mucosa, expressed by the large number of T lymphocytes and macrophages, and that the greatest intensity of local response may be associated with the best prognosis.</p

Microstructure of reaction zone in WCp/duplex stainless steels matrix composites processing by laser melt injection

The laser melt injection (LMI) process has been used to create a metal matrix composite consisting of 80gm sized multi-grain WC particles embedded in three cast duplex stainless steels. The microstruture was investigated by scanning electron microscopy with integrated EDS and electron back-scatter diffraction/orientation imaging microscopy. In particular the search of the processing parameters, e.g. laser power density, laser beam scanning speed and powder flow rate, to obtain crack free and WCp containing surface layer, has been examined. Before the injection of ceramic particles into remelted surface layer, the influence of processing parameters of laser surface remelting on the microstructure and properties of selected duplex steels was also investigated. Although after simple laser surface remelting the austenitic phase is almost not present inside remelted layer, in the case of LMI the austenite was observed in vicinity of WC particles, due to increase of carbon content acting as austenite stabilizer. The diffusion of carbon in the reaction zone results also in a formation Of W2C phase in the neighborhood of WC particles with a strong orientation relationship between them. The maximum volume fraction of the particles achieved in the metal matrix composite layer was about 10% and a substantial increase in hardness was observed, i.e. 575 HV0.2 for the matrix with embedded particles in comparison to 290 HV0.2 for untreated cast duplex stainless steels. (c) 2007 Elsevier B.V. All rights reserved.202102113212