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Different Pathological Conditions (different + pathological_condition)
Selected AbstractsImmunohistochemical localization of insulin-like growth factor-II and its binding protein-6 in human epithelial cells of MalassezEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2003Werner Götz So-called epithelial rests of Malassez are derived from the Hertwig's root sheath and are located in the periodontal ligament, with still unknown functions. Different pathological conditions may lead to proliferation of these otherwise non-proliferative cell clusters. The insulin-like growth factor (IGF) system is an important growth factor system controlling proliferation and differentiation. In our study on Malassez cells from extracted human deciduous teeth, we investigated their structure by means of light and electron microscopy. Although they appeared as cellular clusters with a uniform epithelial phenotype, immunohistochemical analyses of components of the IGF system revealed an unique pattern: weak immunoreactivity could be seen for IGF-II while among all IGF binding proteins (IGFBPs) only IGFBP-6 and weakly IGFBP-4 were detectable in epithelial cells of Malassez. Since IGFBP-6 has a very high affinity for IGF-II and can inhibit its functions, we discuss that, in the normal periodontal ligament, autocrine IGFBP-6 may function as an antiproliferative molecule suppressing mitogenic effects of IGFs on Malassez cells. [source] Activated complement is more extensively present in diseased aortic valves than naturally occurring complement inhibitors: a sign of ongoing inflammationEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2010M. Ter Weeme Eur J Clin Invest 2010; 40 (1): 4,10 Abstract Background, Recent studies indicate a role for complement in the pathogenesis of aortic valve disease. However, the role of naturally occurring anti-complement mediators in this context is unknown. In this study, we have analysed this in three different pathological conditions of the aortic valve: degeneration, atherosclerosis and bacterial endocarditis. Materials and methods, Human aortic valves were obtained at autopsy (n = 30): 5 control valves, 10 aortic valves with atherosclerotic changes, 10 aortic valves with degenerative changes and 5 degenerative changed aortic valves with bacterial infection. These valves were analysed immunohistochemically for the presence of activated complement (C3d and C5b9) and the complement inhibitors C1-inh and clusterin. Areas of positivity were then quantified. Results, C3d, C5b9 and the complement inhibitors C1-inh and clusterin depositions were mainly found in the endothelium and extracellular matrix in aortic valves. All these mediators were already present in control valves, but the area of positivity increased significantly in response to the different diseases, with the highest increase in response to bacterial endocarditis. Interestingly, in all three aortic diseases, the depositions of complement were significantly more widespread than that of their inhibitors. Conclusions, Our study indicates that anti-complement mediators (C1-inh and clusterin) are deposited in diseased aortic valves together with activated complement, indicating an existing counter response against complement locally in the valve. However, deposition of activated complement is significantly more widespread than that of its inhibitors, which could explain ongoing inflammation in those diseased aortic valves. [source] An In Vitro Study of the Ultrasonic Axial Transmission Technique at the Radius: 1-MHz Velocity Measurements Are Sensitive to Both Mineralization and Intracortical Porosity,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2004Emmanuel Bossy Abstract The ultrasonic axial transmission technique allows for investigating skeletal sites such as the cortical layer of long bones (radius, tibia, phalanges). Using synchrotron radiation ,CT, we investigated, in vitro, the relationships between 1-MHz axial transmission SOS measurements at the radius and site-matched measurements of C.Th, POR, MIN, and vBMD. Introduction: The ultrasonic axial transmission technique allows for investigating skeletal sites such as the cortical layer of long bones (radius, tibia, phalanges). Materials and Methods:Using synchrotron radiation ,CT, we investigated, in vitro, the relationships between 1-MHz axial transmission speed of sound (SOS) measurements at the radius and site-matched measurements of cortical thickness (C.Th), intracortical porosity (POR), tissue mineralization (MIN), and volumetric BMD (vBMD). SOS measurements were based on bidirectional axial transmission and were performed with a 1-MHz proprietary probe on 39 excised human radii. Results: The highest correlations between SOS values and bone parameters (R2SOS/POR = 0.28, p < 10,3; R2SOS/MIN = 0.38, p < 10,4; R2SOS/vBMD = 0.57, p < 10,3) were found for bone parameters assessed in a 1-mm-thick periosteal region of the cortex rather than throughout the whole cortex. The observed moderate correlation between SOS and C.Th values (R2SOS/C.Th = 0.20, p < 10,2) disappeared when controlled for other variables. The two best multilinear predictive models, including either BMD alone or the pair of dependent variables MIN and POR (all assessed in the periosteal cortex), were equally accurate in predicting SOS values (R2SOS/(POR,MIN) = 0.59, p < 10,5; R2SOS/vBMD = 0.57, p < 10,5). Conclusion: For the first time, the respective adjusted contributions of POR (,24 m/s%,1) and tissue mineralization (+3.5 m/s/mg/cm,3) to SOS values were assessed. These results suggest potential sensitivity of axial transmission SOS values to changes in cortical bone status under different pathological conditions or treatments affecting POR and/or tissue mineralization. [source] Progress technology in microencapsulation methods for cell therapyBIOTECHNOLOGY PROGRESS, Issue 4 2009Jean-Michel Rabanel Abstract Cell encapsulation in microcapsules allows the in situ delivery of secreted proteins to treat different pathological conditions. Spherical microcapsules offer optimal surface-to-volume ratio for protein and nutrient diffusion, and thus, cell viability. This technology permits cell survival along with protein secretion activity upon appropriate host stimuli without the deleterious effects of immunosuppressant drugs. Microcapsules can be classified in 3 categories: matrix-core/shell microcapsules, liquid-core/shell microcapsules, and cells-core/shell microcapsules (or conformal coating). Many preparation techniques using natural or synthetic polymers as well as inorganic compounds have been reported. Matrix-core/shell microcapsules in which cells are hydrogel-embedded, exemplified by alginates capsule, is by far the most studied method. Numerous refinement of the technique have been proposed over the years such as better material characterization and purification, improvements in microbead generation methods, and new microbeads coating techniques. Other approaches, based on liquid-core capsules showed improved protein production and increased cell survival. But aside those more traditional techniques, new techniques are emerging in response to shortcomings of existing methods. More recently, direct cell aggregate coating have been proposed to minimize membrane thickness and implants size. Microcapsule performances are largely dictated by the physicochemical properties of the materials and the preparation techniques employed. Despite numerous promising pre-clinical results, at the present time each methods proposed need further improvements before reaching the clinical phase. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] The crucial role of metal ions in neurodegeneration: the basis for a promising therapeutic strategyBRITISH JOURNAL OF PHARMACOLOGY, Issue 8 2005Alessandra Gaeta The variety of factors and events involved in neurodegeneration renders the subject a major challenge. Neurodegenerative disorders include a number of different pathological conditions, which share similar critical metabolic processes, such as protein aggregation and oxidative stress, both of which are associated with the involvement of metal ions. In this review, Alzheimer's disease, Parkinson's disease and prion disease are discussed, with the aim of identifying common trends underlying these devastating neurological conditions. Chelation therapy could be a valuable therapeutic approach, since metals are considered to be a pharmacological target for the rationale design of new therapeutic agents directed towards the treatment of neurodegeneration. British Journal of Pharmacology (2005) 146, 1041,1059. doi:10.1038/sj.bjp.0706416 [source] Magnetic resonance spectroscopy in anxiety disordersACTA NEUROPSYCHIATRICA, Issue 2 2008Clarissa Trzesniak Objective:, Magnetic resonance spectroscopy (MRS) is a non-invasive in vivo method used to quantify metabolites that are relevant to a wide range of brain processes. This paper briefly describes neuroimaging using MRS and provides a systematic review of its application to anxiety disorders. Method:, A literature review was performed in the PubMed, Lilacs and Scielo databases using the keywords spectroscopy and anxiety disorder. References of selected articles were also hand-searched for additional citations. Results:, Recent studies have shown that there are significant metabolic differences between patients with anxiety disorders and healthy controls in various regions of the brain. Changes were mainly found in N -acetylaspartate, which is associated with neuronal viability, but some of them were also seen in creatine, a substance that is thought to be relatively constant among individuals with different pathological conditions. Conclusions:, MRS is a sophisticated neuroimaging technique that has provided useful insights into the biochemical and neurobiological basis of many anxiety disorders. Nevertheless, its utilization in some anxiety disorders is still modest, particularly social phobia and generalised anxiety. Although it is an extremely useful advance in neuroimaging, further research in other brain areas and patient populations is highly advisable. [source] | ||||||||||