1,901 research outputs found

    Apoptosis in Displaced Temporomandibular Joint Disc with and without Reduction: An Immunohistochemical Study

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    Internal derangement (ID) of the temporomandibular joint (TMJ) is due to an abnormal relationship of the articular disc to the mandibular condyle, glenoid fossa and articular eminence. The two most common types of internal derangement are anterior disc displacement with (ADDwR) and without reduction (ADDwoR). Disc displacement is associated with degenerative tissue changes. The histological features of discs from patients with TMJ ID reflect a general remodelling caused by abnormal loading. A correlation has been demonstrated between TMJ ID and apoptosis. Few investigations have addressed the role of apoptosis or caspase activity in TMJ ID. The apoptosis activation process was studied in different areas of discs from 18 patients with ID (both ADDwR and ADDwoR) and four cadavers (controls), with emphasis on the expression of caspase 3, whose activation makes the death process irreversible. The results showed a greater proportion of caspase 3‐positive cells in ADDwR and ADDwoR than in control discs. Immunopositivity also varied between disc areas; in particular, in ADDwoR sections labelled cells were significantly more numerous (P \u3c 0.01) in the posterior disc attachment than in the anterior and intermediate bands. In addition, a significantly greater proportion of labelled cells was seen in the anterior (+) and intermediate (++) band of ADDwR compared with ADDwoR discs both bands (P \u3c 0.05). These data suggest the importance of programmed cell death in the progression of TMJ ID

    Occurrence and Regional Distribution of TRAIL and DR5 on Temporomandibular Joint Discs: Comparison of Disc Derangement with and without Reduction

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    Background Tumor necrosis factor (TNF)–related apoptosis-inducing ligand (TRAIL) is an apoptosis-inducing member of the TNF gene family which triggers apoptotic signals by interaction with its receptors. It has been suggested to be a major contributing factor to tissue degeneration. Objective The present study investigated, through immunohistochemistry, the regional expression of TRAIL and in temporomandibular joint (TMJ) disc of anterior disc displacement with reduction (ADDwR) and without reduction (ADDwoR) patients, to help determine the relationship between TMJ disc displacement and apoptosis. Study design We studied 18 TMJ diseased discs affected by disc displacement without or with reduction and 4 normal TMJ discs. Specimens were processed for immunohistochemistry to evaluate TRAIL and its receptor DR5 expression. Results Disc tissues from internal derangements (both ADDwR and ADDwoR) exhibited a much higher percentage of TRAIL- and DR5-positive cells as well as stain intensity compared with normal tissue though with regional variation according to the portion of the disc. There was a significantly higher percentage of stained cells in the posterior disc attachment compared with the anterior or intermediate bands of both ADDwR and ADDwoR discs for TRAIL and DR5. Conclusions TRAIL and DR5 are overexpressed in displaced human TMJ disc, especially in the posterior disc attachment. These results suggest a possible pivotal role of the TRAIL/DR5 system in TMJ disc degeneration

    Surgical Treatment for Renal Cell Carcinoma

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    Despite recent advances in chemotherapy, radiation therapy and immunology, renal cell carcinoma can best be treated by early detection and radical surgery. Today, radical nephrectomy is the standard surgery of choice for removing malignant renal tumors. Of the surgical procedures that have been used in the past, the transabdominal incision offers the best exposure of retroperitoneal structures at the diaphragmatic level and the contralateral renal vasculature. Occasionally, supraradical procedures are recommended if tumor size and location require this approach

    Experimental and theoretical evidences for the ice regime in planar artificial spin ices

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    In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI can open up the panorama of exploring distinct ground states and thermally magnetic monopole excitations. It is shown that a particular ASI lattice will provide a richer thermodynamics with nanomagnet spins experiencing less restriction to flip precisely in a kind of rhombic lattice. This can be observed by analysis of only three types of rectangular artificial spin ices (RASI). Denoting the horizontal and vertical lattice spacings by a and b, respectively, then, a RASI material can be described by its aspect ratio γ\gamma=a/b. The rhombic lattice emerges when γ\gamma=3\sqrt{3}. So, by comparing the impact of thermal effects on the spin flips in these three appropriate different RASI arrays, it is possible to find a system very close to the ice regime

    Defining and identifying communities in networks

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    The investigation of community structures in networks is an important issue in many domains and disciplines. This problem is relevant for social tasks (objective analysis of relationships on the web), biological inquiries (functional studies in metabolic, cellular or protein networks) or technological problems (optimization of large infrastructures). Several types of algorithm exist for revealing the community structure in networks, but a general and quantitative definition of community is still lacking, leading to an intrinsic difficulty in the interpretation of the results of the algorithms without any additional non-topological information. In this paper we face this problem by introducing two quantitative definitions of community and by showing how they are implemented in practice in the existing algorithms. In this way the algorithms for the identification of the community structure become fully self-contained. Furthermore, we propose a new local algorithm to detect communities which outperforms the existing algorithms with respect to the computational cost, keeping the same level of reliability. The new algorithm is tested on artificial and real-world graphs. In particular we show the application of the new algorithm to a network of scientific collaborations, which, for its size, can not be attacked with the usual methods. This new class of local algorithms could open the way to applications to large-scale technological and biological applications.Comment: Revtex, final form, 14 pages, 6 figure

    Human adult dental pulp CD117/c-kit-positive networks of stromal cells

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    Dental pulp tissue was collected from 6 healthy adult patients, prior to prosthetic treatments, in order to evaluate the in situ phenotype of dental pulp stromal cells and compare with that of dental pulp stem cells. A CD34–/CD44+/CD105–/CD117+/CD146–/nestin– phenotype of stromal cells in the dental pulp core was found. Cells with a similar phenotype, but CD44–, were found in the cell richzone. Dental pulp stromal networks (DPSNs) were found CD117+/CD44+ in the pulp core, but CD117+/CD44– in the cell rich zone. The c-kit-positive DPSNs were contacting pulp nerves and were, in this regard only, comparable to interstitial Cajal cells. Stromal signalling in dental pulp needs further evaluation, in normal tissue as well as a possible cause of persisting pain after endodontic treatment

    Opinion Formation in Laggard Societies

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    We introduce a statistical physics model for opinion dynamics on random networks where agents adopt the opinion held by the majority of their direct neighbors only if the fraction of these neighbors exceeds a certain threshold, p_u. We find a transition from total final consensus to a mixed phase where opinions coexist amongst the agents. The relevant parameters are the relative sizes in the initial opinion distribution within the population and the connectivity of the underlying network. As the order parameter we define the asymptotic state of opinions. In the phase diagram we find regions of total consensus and a mixed phase. As the 'laggard parameter' p_u increases the regions of consensus shrink. In addition we introduce rewiring of the underlying network during the opinion formation process and discuss the resulting consequences in the phase diagram.Comment: 5 pages, eps fig

    A Yule-Simon process with memory

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    The Yule-Simon model has been used as a tool to describe the growth of diverse systems, acquiring a paradigmatic character in many fields of research. Here we study a modified Yule-Simon model that takes into account the full history of the system by means of an hyperbolic memory kernel. We show how the memory kernel changes the properties of preferential attachment and provide an approximate analytical solution for the frequency distribution density as well as for the frequency-rank distribution.Comment: 7 pages, 5 figures; accepted for publication in Europhysics Letter

    Resistencia antimicrobiana de Staphylococcus aislados de la piel de gatos ¿un riesgo para la salud humana?

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    Actualmente, las patologías dermatológicas son una de las causas deconsulta más frecuentes en la práctica veterinaria de animales pequeños,posiblemente debido a los evidentes signos y lesiones que presentan losanimales: prurito, alopecia y olor desagradable, entre otros.  
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