1,806 research outputs found

    Doxorubicin-induced F-actin reorganization in cofilin-1 (nonmuscle) down-regulated CHO AA8 cells.

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    The actin cytoskeleton plays an important role in many cellular processes, including cell mortality, mitosis, cytokinesis, intracellular transport, endocytosis and secretion but also is involved in gene transcription. The dynamics of the actin cytoskeleton is controlled by different classes of actin-binding proteins (ABPs) which regulate the polymerization of actin filaments. In this report we used siRNA against cofilin-1 (nonmuscle) to demonstrate the effect of cofilin on the nuclear and cytoplasmic actin pools in CHO AA8 cells after exposition to various concentrations of doxorubicin. The immunofluorescence studies showed doxorubicin dose dependent tendency to formation the multinucleated giant cells, but also the increase of fluorescence intensity of cofilin in nuclei of untransfected cells. Induction of cell death with doxorubicin treatment in untransfected cells revealed both mitotic catastrophe (in both lower and higher doxorubicin doses) and apoptosis (mostly in higher doxorubicin doses), whereas among cofilin-1 down-regulated cells we observed only mitotic catastrophe. The results suggest that cofilin has apoptosis-inducing ability and that mitotic catastrophe is independent from F-actin content in cell nucleus. In this point of view we conclude that different mechanisms of chromatin reorganization are involved in these two processes. Moreover, we suppose that apoptosis and mitotic catastrophe are independent from each other

    Electron microscope study of the advanced tendinopathy process of the long head of the biceps brachii tendon treated arthroscopically

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    Background: The ultrastructural alterations related to tendinopathy have not been well described. Most studies on this subject have been conducted many years ago and focused on material from the Achilles tendon. It was demonstrated that various comorbidities can affect ultrastructural alterations in the advanced tendinopathy; however, there is very little data on ultrastructural morphology in tendinopathies related to mechanical overload as in case of the long head of the biceps brachii tendon (LHBT). The aim was to determine intermediate ultrastructural alterations in middle to severe grade the LHBT tendinopathy and to establish if they are different than those reported in the literature for other anatomical locations. Materials and methods: In this study we examined the ultrastructure of a series of the LHBT fragments arthroscopically removed due to tendinopathy and inve­stigated the morphology of tenocytes and collagen fibres in cases of the LHBT tendinopathy. Results: In pathological samples tenocytes were randomly scattered, their shape was round and the shape of nuclei was also disrupted. The presence of apoptotic­-like features in tenocytes’ nuclei was noted. All samples showed replacement of collagen fibrils by non-collagen extracellular matrix and diffuse collagen disorganisation. Conclusions: It was demonstrated at ultrastructural level that the LHBT tendino­pathy is not simply a wear and tear phenomenon, since chronic degeneration of the extracellular matrix and tenocytes were present, similarly as in tendinopathies, in other anatomical locations. (Folia Morphol 2018; 77, 2: 371–377

    Sonography in the instability of the long head of the biceps tendon confronted with histopathologic and arthroscopic findings

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    Background: Disorders of the long head of the biceps (LHB) tendon are a common source of shoulder pain and disability. This tendon can be well visualised using ultrasonography; however, little is known if such examination allows clinicians to predict pathological changes of the tendon structure. In the study described below, we compare preoperative sonographic findings with the data from shoulder arthroscopy and microscopic examination of the excised tendon fragments in 19 consecutive patients with LHB tendinopathy and clinical suspicion of its instability.Materials and methods: Preoperative ultrasonographic (US) inspection assessed several features of the tendon, whereas its stability was verified arthroscopically. In all cases, tenodesis or tenotomy procedures were performed and excised tendon fragments were harvested for microscopic examination based on the semiquantitative Bonar score.Results: The most common US findings were hypoechoic areas, tendon thickening, an increased power Doppler signal and mechanical instability. Just as shoulder arthroscopy confirmed all mechanical instability cases detected in US, microscopic assessment revealed advanced degeneration in all samples.Conclusions: Our study indicates that US is a useful tool in identifying cases of advanced instability and LHB tendinopathy, whereas biceps tendon instability is a biomechanically complex, gradually progressing phenomenon, frequently associated with additional shoulder lesions

    Tendon — function-related structure, simple healing process and mysterious ageing

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    Tendons are connective tissue structures of paramount importance to human ability of locomotion. The understanding of their physiology and pathology is gaining importance as advances in regenerative medicine are being made today. So far, very few studies were conducted to extend the knowledge about pathology, healing response and management of tendon lesions. In this paper we summarise actual knowledge on structure, process of healing and ageing of the tendons. The structure of tendon is optimised for the best performance of the tissue. Despite the simplicity of the healing response, numerous studies showed that the problems with full recovery are common and much more significant than we thought; that is why we discussed the issue of immobilisation and mechanical stimulation during healing process. The phenomenon of tendons’ ageing is poorly understood. Although it seems to be a natural and painless process, it is completely different from degeneration in tendinopathy. Recent studies of biological treatment reported faster and optimal healing of the tendons when augmented by growth factors and stem cells. Despite advances in biology of tendons, management of their injuries is still a challenge for physicians; therefore, further studies are required to improve treatment outcomes

    Nanocrystalline materials studied by powder diffraction line profile analysis

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    X-ray powder diffraction is a powerful tool for characterising the microstructure of crystalline materials in terms of size and strain. It is widely applied for nanocrystalline materials, especially since other methods, in particular electron microscopy is, on the one hand tedious and time consuming, on the other hand, due to the often metastable states of nanomaterials it might change their microstructures. It is attempted to overview the applications of microstructure characterization by powder diffraction on nanocrystalline metals, alloys, ceramics and carbon base materials. Whenever opportunity is given, the data provided by the X-ray method are compared and discussed together with results of electron microscopy. Since the topic is vast we do not try to cover the entire field

    Evaluation of the Safety of Neauvia Stimulate Injectable Product in Patients with Autoimmune Thyroid Diseases Based on Histopathological Examinations and Retrospective Analysis of Medical Records

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    The aim of this study was to test the effect of hyaluronic acid cross-linked with polyethylene glycol containing micronized portions of calcium hydroxyapatite (Neauvia Stimulate) on both local tissue and systemic consequences, which are crucial from the perspective of long-term safety, in patients suffering from Hashimoto's disease. This most common autoimmune disease is a frequently mentioned contraindication to the use of fillers based on hyaluronic acid as well as biostimulants based on calcium hydroxyapatite. Broad-spectrum aspects of histopathology were analyzed to identify key features of inflammatory infiltration before the procedure and 5, 21, and 150 days after the procedure. A statistically significant effect on the reduction of the intensity of the inflammatory infiltration in the tissue in relation to the state before the procedure was demonstrated, combined with a reduction in the occurrence of both antigen-recognizing (CD4) and cytotoxic (CD8) T lymphocytes. With complete statistical certainty, it was demonstrated that the treatment with Neauvia Stimulate had no effect on the levels of these antibodies. All this corresponds with the risk analysis that showed no alarming symptoms during the time of observation. The choice of hyaluronic acid fillers cross-linked with polyethylene glycol should be considered justified and safe in the case of patients suffering from Hashimoto's disease

    Proton-proton elastic scattering at the LHC energy of {\surd} = 7 TeV

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    Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at {\surd}s = 7 TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (sbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t|, the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of d t = 0.1GeV p|t|. In this letter, first results of the differential cross section are presented covering a |t|-range from 0.36 to 2.5GeV2. The differential cross-section in the range 0.36 < |t| < 0.47 GeV2 is described by an exponential with a slope parameter B = (23.6{\pm}0.5stat {\pm}0.4syst)GeV-2, followed by a significant diffractive minimum at |t| = (0.53{\pm}0.01stat{\pm}0.01syst)GeV2. For |t|-values larger than ~ 1.5GeV2, the cross-section exhibits a power law behaviour with an exponent of -7.8_\pm} 0.3stat{\pm}0.1syst. When compared to predictions based on the different available models, the data show a strong discriminative power despite the small t-range covered.Comment: 12pages, 5 figures, CERN preprin

    Baseline new bone formation does not predict bone loss in ankylosing spondylitis as assessed by quantitative computed tomography (QCT) - 10-year follow-up

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    <p>Abstract</p> <p>Background</p> <p>To evaluate the relationship between bone loss and new bone formation in ankylosing spondylitis (AS) using 10-year X-ray, dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT) follow-up.</p> <p>Methods</p> <p>Fifteen AS patients free from medical conditions and drugs affecting bone metabolism underwent X-ray, DXA and QCT in 1999 and 2009.</p> <p>Results</p> <p>In spine QCT a statistically significant (p = 0,001) decrease of trabecular bone mineral content (BMC) was observed (change Âą SD: 18.0 Âą 7.3 mg/cm<sup>3</sup>). In contrast, spine DXA revealed a significant increase of bone mineral density (change Âą SD: -0.15 Âą 0.14 g/cm<sup>2</sup>). The mean BMC, both at baseline and follow-up was significantly lower (p = 0.02 and p = 0.005, respectively) in advanced radiological group as compared to early radiological group. However, in multiple regression model after adjustment for baseline BMC, the baseline radiological scoring did not influence the progression of bone loss as assessed with QCT (p = 0.22, p for BMC*X-ray syndesmophyte scoring interaction = 0.65, p for ANOVA-based X-ray syndesmophyte scoring*time interaction = 0.39). Baseline BMC was the only significant determinant of 10-year BMC change, to date the longest QCT follow-up data in AS.</p> <p>Conclusions</p> <p>In AS patients who were not using antiosteoporotic therapy spine trabecular bone density evaluated by QCT decreased over 10-year follow-up and was not related to baseline radiological severity of spine involvement.</p
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