COMPARATIVE-EVALUATION-OF-TWO-VIABILITY ASSAYS ON BIODEGRADABLE POLYMER FOAMS FOR POTENTIAL BONE REGENERATION

The purpose of the present study was to evaluate comparatively the cytotoxicity of two foams prepared by phosphorylated cellulose and phosphorylated PVA using two common assays, MTT classic assay and Cell-titer blue assay. Two foams with potential applications for bone substitute were evaluated. Both evaluated samples (phosphorylated cellulose and phosphorylated PVA) conditioned as foams showed a very good compatibility against osteoblast-like cells. The main advantage of the cell titer blue protocol for cell proliferation against MTT assay is represented by the possibility of direct addition of the assay reagents onto the wells with the material to be evaluated

CELL PROLIFERATION AND MIGRATION ASSAY ON POLYMER SURFACES

Cell proliferation and migration on phosphonated polymer surfaces may impair cell adherence and migration. The aim of the present study was to evaluate the ability of osteoblast-like cells to migrate at the surface of the phosphonated chitosan pellicle compared to normal chitosan pellicle. Results. Cells proliferated and migrated at different rates according to surface charge. Negative surfaces showed lower adherence and the migration difference could be quantified. Conclusions. Cell migration on polymer surfaces can be successfully evaluated by improved scratch test performed directly on polymer pellicles. Migration assay can be quantified by measuring the scratch size following separator removal. At the same time, viability assays are applicable following this improved scratch test while with no cells are damaged by mechanical means mechanically damage

Pharmacophore identification for matrix metalloproteinases by in silico investigations

Pharmacophores are a collection of universal chemical properties that characterizes the specific action of a ligand in the active site of a three-dimensional conformational model of a molecule. Aim. To define the pharmacophores, from some MMP-inhibitor complexes, defined experimentally in protein databank. Material and methods. We have used LiganScout software that supports the pharmacophore alignment and of important ligand molecules, based on their properties, in arbitrary combinations. The alignment of the two elements is realized by pairing only regardless the number of aligned elements. We have chosen 9 files crystalographically defined as MMP-inhibitor complexes: 1eub, 1fls, 1xuc, 1xud, 1xur, 1you, 1ztq, 456c and 830c, respectively. Results and discussions. Different type of inhibitors shows different pharmacophores, with respect to Zn coordination and for the hydrophobic tunnel in the enzyme binding pocket. Conclusions: it is important to understand substrate selectivity in order to develop new synthetic MMP inhibitors. Not only the Zn ion coordination in the P site is important but also the hydrophobicity of S1 tunnel can be a step in further computer design for potent inhibitor or enzyme modulation factors

Observations about the Principal Components Analysis and Data Clustering Techniques in the Study of Medical Data

Abstract—The medical data statistical analysis often requires the using of some special techniques, because of the particularities of these data. The principal components analysis and the data clustering are two statistical methods for data mining very useful in the medical field, the first one as a method to decrease the number of studied parameters, and the second one as a method to analyze the connections between diagnosis and the data about the patient’s condition. In this paper we investigate the implications obtained from a specific data analysis technique: the data clustering preceded by a selection of the most relevant parameters, made using the principal components analysis. Our assumption was that, using the principal components analysis before data clustering- in order to select and to classify only the most relevant parameters – the accuracy of clustering is improved, but the practical results showed the opposite fact: the clustering accuracy decreases, with a percentage approximately equal with the percentage of information loss reported by the principal components analysis. Keywords—Data clustering, medical data, principal components analysis. I

A semiquantitative analysis technique regarding immunohistochemical detection for matrix metalloproteinases

Modern image processing techniques are used today in order to evaluate immunohistochemical detection for various markers, especially those important for malignant tumor diagnosis and remodeling processes. Evaluating the immunohistochemical markers detection may be completed by a quantitative analysis. We have used samples of normal and fibrous tissue from surgical scars harvested after 2 months from surgery. We have investigated the immunohistochemically marked areas and we have performed a semiquantitative image analysis, using an academic, open sourcesoftware, ImageJ v. 1.38. After image adjustments (binarization) and correction, we have applied a deconvolution filter after which we have performed and analyzed a histogram of the selected area. The binarized areas were measured and compared for three samples of each tissue. We have followed the semiquantitative analysis of MMP-2 and MMP-9 presence on the investigated samples. This technique, even if controversial, allows us a fast analysis of common markers detected by immunohistochemistr

CORELATIONS BETWEEN THE CLINICAL AND MORFOLOGICAL ASPECTS AND THE MOLECULAR MARKERS IN THE MALIGNANT TRANSFORMATION OF THE ORAL LEUKOPLAKIAS

The leukoplakia injuries represent the most frequent premalignant oral injuries. Their clinical and histopathological features are not always significant for the malignant transformation and, implicitly, for their diagnosis. The important progress achieved in the last three decades for the understanding of the cellular and molecular mechanisms of the leukoplakia lesions have not managed to significantly reduce the prevalence of the oral squamouscellular carcinomas. Therefore, it is necessary the identification and the characterization of the molecular markers which, together with the clinical and morphological aspects, can improve the management of these lesions

Urologic Cancer Molecular Biology

An adequate understanding of the molecular mechanisms of the most common urological cancers is necessary for a correct approach to diagnosis, precise treatment, but also for the follow-up of these patients. It is necessary to understand the molecular mechanisms underlying the carcinogenic processes, the molecular pathways involved in this process, and also to describe the biomarkers useful for diagnosis but also for predictability, treatment, and natural history. In addition, it would be useful to describe a list of useful molecules currently under investigation as possible biomarkers to improve the income of cancer patients