1,721,188 research outputs found
A paradox of cadmium: a carcinogen that impairs the capability of human breast cancer cells to induce angiogenesis
No full textCadmium, a highly persistent heavy metal, has been categorized as a human carcinogen. Even though it is known that cadmium acts as estrogens in breast cancer cells, several studies failed to demonstrate whether cadmium is a causal factor for breast cancer. The lack of a strong association between cadmium and breast cancer could be found in the antiangiogenic properties of this heavy metal, which might counteract its carcinogenic properties in the progression of breast cancer. In this study, we exposed estrogen-responsive breast cancer cells to subtoxic levels of cadmium, and we evaluated their angiogenic potential using the chick embryo chorioallantoic membrane assay. Exposure of breast cancer cells to subtoxic levels of cadmium significantly inhibited the angiogenic potential of the breast cancer cell line, suggesting the possibility that cadmium might negatively regulate the production of proangiogenic factors in breast cancer cells. Our results suggest that cadmium might exert a paradoxical effect in breast cancer: on the one hand, it could promote carcinogenesis, and, on the other hand, it could delay the onset of tumors by inhibiting breast cancer cell-induced angiogenesis
Evaluation of biological risks connected with implementation of a novel dissection hall
No full textEvaluation of biological risks connected with implementation of a novel dissection hal
Effects of vitamin D-binding protein-derived macrophage-activating factor on human breast cancer cells
Full text linkBACKGROUND: Searching for additional therapeutic tools to fight breast cancer, we investigated the effects of vitamin D-binding protein-derived macrophage activating factor (DBP-MAF, also known as GcMAF) on a human breast cancer cell line (MCF-7). MATERIALS AND METHODS: The effects of DBP-MAF on proliferation, morphology, vimentin expression and angiogenesis were studied by cell proliferation assay, phase-contrast microscopy, immunohistochemistry and western blotting, and chorioallantoic membrane (CAM) assay. RESULTS: DBP-MAF inhibited human breast cancer cell proliferation and cancer cell-stimulated angiogenesis. MCF-7 cells treated with DBP-MAF predominantly grew in monolayer and appeared to be well adherent to each other and to the well surface. Exposure to DBP-MAF significantly reduced vimentin expression, indicating a reversal of the epithelial/mesenchymal transition, a hallmark of human breast cancer progression. CONCLUSION: These results are consistent with the hypothesis that the known anticancer efficacy of DBP-MAF can be ascribed to different biological properties of the molecule that include inhibition of tumour-induced angiogenesis and direct inhibition of cancer cell proliferation, migration and metastatic potential
Tensegrity and plasma for skin regeneration
No full textBACKGROUND: Mechanical stresses induce variations in tissue tensegrity leading to cell proliferation and differentiation thus contributing to tissue remodelling. Besides mechanical forces, skin remodelling may be induced by the application of plasma, a new type of energy delivery resulting in controlled heat damage. Here we demonstrate that mechanical stress induced by the application of vacuum increases the efficacy of plasma in skin regeneration treatment. METHODS: Vacuum alone and vacuum plus plasma at different energies were applied to rat skin and biopsies collected at different time intervals after treatments. Skin integrity, collagen arrangement, inflammation and myofibroblast differentiation were assessed by Masson's trichrome staining. Procollagen synthesis was evaluated by immunohistochemistry. RESULTS: Vacuum alone induced significant and temporary alterations in the distribution of collagen bundles, with concomitant procollagen synthesis in the dermis; no myofibroblasts and no signs of inflammation were observed. Vacuum plus plasma determined an important spatial modification of collagen bundles, more intense than vacuum or plasma alone. Significant increase of procollagen synthesis, numerous myofibroblasts but slight sign of inflammation appeared after the treatment. CONCLUSION: Vacuum mechanically stimulated fibroblasts, producing changes in collagen arrangement and procollagen synthesis. Plasma led to the same effects through thermal damage. Application of a combined treatment consisting in vacuum plus plasma induced more remarkable effects on skin regeneration with relatively low plasma energies and no relevant side effect
Gc protein-derived macrophage-activating factor (GcMAF) stimulates cAMP formation in human mononuclear cells and inhibits angiogenesis in chick embryo chorionallantoic membrane assay
No full textAbstract: The effects of Gc protein-derived macrophage-activating factor (GcMAF) have been studied in cancer and other conditions where angiogenesis is deregulated. In this study, we demonstrate for the first time that the mitogenic response of human peripheral blood mononuclear cells (PBMCs) to GcMAF was associated with 3'-5'-cyclic adenosine monophosphate (cAMP) formation. The effect was dose dependent, and maximal stimulation was achieved using 0.1 ng/ml. Heparin inhibited the stimulatory effect of GcMAF on PBMCs. In addition, we demonstrate that GcMAF (1 ng/ml) inhibited prostaglandin E(1)- and human breast cancer cell-stimulated angiogenesis in chick embryo chorionallantoic membrane (CAM) assay. Finally, we tested different GcMAF preparations on CAM, and the assay proved to be a reliable, reproducible and inexpensive method to determine the relative potencies of different preparations and their stability; we observed that storage at room temperature for 15 days decreased GcMAF potency by about 50%. These data could prove useful for upcoming clinical trials on GcMAF
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effect of ultrasounds on neurons and microglia: Cell viability and automatic analysis of cell morphology
No full textUltrasounds, besides their well-established medical imaging role, influence the homeostasis of complex anatomical systems including the physiology of neurons and glia and the permeability of the blood brain barrier. In this study, neurons and microglial cells were treated with ultrasounds (commonly used in diag- nostics) and differences in cell proliferation and morphology were evaluated in comparison to control, untreated cells. Cell proliferation was evaluated by standard viability assessment, while the quantitative analysis of cell morphology, usually performed by edge and line detection algorithms, required the development of a new special algorithm. In fact, traditional software methodologies do not provide the appropriate tools for morphological analysis of neurons and microglial cells, typically characterized by a roughly triangular body and numerous elongations of different lengths resulting in a complex neuron–microglia network. This new method, based on a modified Hough Transform algorithm using a matching operator instead of the common gradient filter, enabled the automatic identification of cell elongations and branches, the extraction of related information, and the comparison of the data between control and treated neurons, as well as microglial cells.
Results, based on the development of the new algorithm, showed that in ultrasound-treated cells, the number of elongations, as well as their maximum and mean lengths, increased significantly in comparison to control, untreated cells.
These results were consistent with the standard microscopic evaluation. Furthermore, a significant correlation between cell morphology and proliferation suggested that ultrasounds induced cell differentiation affecting cell morphology, as well as the ability of neurons and microglial cells to form complex networks. Our results suggest the possibility of using ultrasounds, currently utilized in diagnostics, to reconstitute neuronal and microglial circuits that are often altered in neurodegenerative and neurodevelopmental disorders
Effect of paricalcitol and GcMaf on angiogenesis and human peripheral blood mononuclear cell proliferation and signalling
No full textBackground: In addition to its role in calcium homeostasis and bone mineralization, vitamin D is involved in immune defence, cardiovascular function, inflammation and angiogenesis, and these pleiotropic effects are of interested in the treatment of chronic kidney disease. Here we investigated the effects of paricalcitol, a nonhypercalcemic vitamin D analogue, on human peripheral blood mononuclear cell proliferation and signaling, and on angiogenesis. These effects were compared with those of a known inhibitor of angiogenesis pertaining to the vitamin D axis, the vitamin D-binding protein-derived Gc-macrophage activating factor (GcMAF). Methods: Since the effects of vitamin D receptor agonists are associated with polymorphisms of the gene coding for the receptor, we measured the effects of both compounds on mononuclear cells harvested from subjects harboring different BsmI polymorphisms. Results: Paricalcitol inhibited mononuclear cell viability with the bb genotype showing the highest effect. GcMAF, on the contrary, stimulated cell proliferation, with the bb genotype showing the highest stimulatory effect. Both compounds stimulated 3'-5'-cyclic adenosine monophosphate formation in mononuclear cells with the highest effect on the bb genotype. Paricalcitol and GcMAF inhibited the angiogenesis induced by proinflammatory prostaglandin E1. Conclusions: Polymorphisms of the vitamin D receptor gene, known to be associated with the highest responses to vitamin D receptor agonists, are also associated with the highest responses to GcMAF. These results highlight the role of the vitamin D axis in chronic kidney disease, an axis which includes vitamin D, its receptor and vitamin D-binding protein-derived GcMAF
Evidence of immune system morpho-functional damages induced by Cadmium in Apis mellifera
No full textIn previous researches severe damages induced by Cadmium (an ubiquitary environmental pollutant whose intracellular oxidative effects are increasingly lethal) exposure in human have been demonstrated. Morphologic effects were observed in Central Nervous System, liver, kidney, placenta. Recently, the involvement of immune system in Cadmium intoxication was demonstrated in mammalians; we, therefore, tried to evidence such effect in a simple model as Apis Mellifera. In this animal the immune system is represented by “fat bodies” which produce proteins active in defense against pathogenic agents. It is important to stress out that a dangerous syndrome causing the collapse of Apis mellifera hives has intensified recently, in Europe and North America. Current research in this field is oriented towards identifying a synergy of contributing factors to the weakening of the hive. In this paper, we aim to determine whether contamination by cadmium may have an immunosuppressive effect on the insect. Preliminary results denote that the heavy metal causes a severe damage in fat bodies, leading to substantial immunodeficiency in exposed bees, suggesting that in polluted areas the hives may have difficulty in dealing with pests and pathogens that threaten them
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