187 research outputs found

    Effect of cooling rate on phase transformation in 6-8 wt % YSZ APS TBCs

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    In properly produced as-sprayed thermal barrier coatings of yttria partially stabilized zirconia (7YSZ) the only phase that can be found is the metastable tetragonal prime structure t’. Even though t’ is sometimes called “not transformable”, because it behaves as practically stable up to rather high temperature, long term exposure much above 1200 °C produces its equilibrium transformation in tetragonal and cubic phases. During cooling down to room temperature the tetragonal phase will transform in monoclinic one. Although it is considered a martensitic transformation, fast cooling after prolonged high temperature exposure (over 1300°C) can avoid or limit the evolution from tetragonal to monoclinic structure. The effect of the cooling rate on this transformation has been investigated in free standing TBCs both with porous microstructure and dense vertically cracked one, exposed at 1400°C for 100 hours. The samples have been analysed by XRD and subsequent Rietveld refinement analysis to quantify the phase content: the results highlight that different cooling rates give different monoclinic contents, confirming the cooling rate effect on the transformation. If the phase equilibrium was not achieved due to fast cooling, it could be restored at low temperature for short duration independent of cooling rate. It was demonstrated that after exposure at 1400°C followed by fast cooling, the equilibrium phase composition could be achieved by a low temperature heat treatment of 12h at 200°C. For validation, the quantitative phase analysis has been performed before and after that low temperature heat treatment. Moreover the unit cell volume per each phase has been measured, for both samples at equilibrium and samples after fast cooling. Therefore the strain induced by the volume increase due to monoclinic phase formation has been calculated and compared with TBC maximum allowable strain

    Hair-thread strangulation syndrome in childhood: a systematic review.

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    Hair-thread strangulation syndrome describes the constriction of a body part by a tightly wound hair or thread. This research aims to review the literature about this entity. A systematic review was performed to characterise hair-thread strangulation syndrome in subjects aged ≀16 years. This pre-registered review (PROSPERO ID: CRD42022363996) followed the PRISMA methodology. Subjects with digital strangulation were significantly younger (median = 4.0 [interquartile range: 2.0-6.1] months; n = 143) than females with genital strangulation (9.0 [6.8-11] years; n = 36), males with genital strangulation (5.1 [1.9-8.0] years; n = 36), and subjects with non-digital and non-genital strangulation (24 [13-48] months; n = 11). Digital strangulation was followed by an amputation in five (3.5%) and a reconstructive surgical intervention in seven (4.9%) cases. Sequelae occurred in four (11%) cases after female genital strangulation: clitoris autoamputation (n = 2) and surgical removal of a necrotic labium minus (n = 2). Severe complications were observed in 14 (39%) cases with male genital strangulation: urethral fistula (n = 7), urethral transection (n = 2), and partial penile autoamputation (n = 5). A partial uvular autoamputation was observed in one case (9.0%) with non-digital and non-genital strangulation. Early recognition and management are crucial to avoid sequelae or long-term care in hair-thread strangulation syndrome

    Hair-thread strangulation syndrome in childhood: a systematic review

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    INTRODUCTION: Hair-thread strangulation syndrome describes the constriction of a body part by a tightly wound hair or thread. This research aims to review the literature about this entity. METHODS: A systematic review was performed to characterise hair-thread strangulation syndrome in subjects aged ≀16 years. This pre-registered review (PROSPERO ID: CRD42022363996) followed the PRISMA methodology. RESULTS: Subjects with digital strangulation were significantly younger (median = 4.0 [interquartile range: 2.0–6.1] months; n = 143) than females with genital strangulation (9.0 [6.8–11] years; n = 36), males with genital strangulation (5.1 [1.9–8.0] years; n = 36), and subjects with non-digital and non-genital strangulation (24 [13–48] months; n = 11). Digital strangulation was followed by an amputation in five (3.5%) and a reconstructive surgical intervention in seven (4.9%) cases. Sequelae occurred in four (11%) cases after female genital strangulation: clitoris autoamputation (n = 2) and surgical removal of a necrotic labium minus (n = 2). Severe complications were observed in 14 (39%) cases with male genital strangulation: urethral fistula (n = 7), urethral transection (n = 2), and partial penile autoamputation (n = 5). A partial uvular autoamputation was observed in one case (9.0%) with non-digital and non-genital strangulation. CONCLUSIONS: Early recognition and management are crucial to avoid sequelae or long-term care in hair-thread strangulation syndrome

    Aberrant antigenic expression in extranodal NK/T-cell lymphoma: a multi-parameter study from Thailand

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    <p>Abstract</p> <p>Background</p> <p>Extranodal NK/T-cell lymphoma, nasal type (ENKTL) is not common worldwide, but it is the most common T- and NK-cell lymphomas in many Asian countries. Immunophenotypic profiles were studied based on limited series. The authors, therefore, studied on ENKTL according to characterize immunophenotypic profiles as well as the distribution of EBV subtype and LMP-1 gene deletion.</p> <p>Methods</p> <p>By using tissue microarray (TMA), immunohistochemical study and EBV encoded RNA (EBER) in situ hybridization were performed. T-cell receptor (TCR) gene rearrangement, EBV subtyping, and LMP-1 gene deletion were studied on the available cases.</p> <p>Results</p> <p>There were 22 cases eligible for TMA. ENKTL were positive for CD3 (91%), CD5 (9%), CD7 (32%), CD4 (14%), CD56 (82%), TIA-1 (100%), granzyme B (95%), perforin (86%), CD45 (83%), CD30 (75%), Oct2 (25%), and IRF4/MUM1 (33%). None of them was positive for ÎČF1, CD8, or CD57. TCR gene rearrangement was negative in all 18 tested cases. EBV was subtype A in all 15 tested cases, with 87% deleted LMP-1 gene. Cases lacking perforin expression demonstrated a significantly poorer survival outcome (p = 0.008).</p> <p>Conclusions</p> <p>The present study demonstrated TIA-1 and EBER as the two most sensitive markers. There were a few CD3 and/or CD56 negative cases noted. Interestingly, losses of CD45 and/or CD7 were not uncommon while Oct2 and IRF4/MUM1 could be positive in a subset of cases. Based on the present study in conjunction with the literature review, determination of PCR-based TCR gene rearrangement analysis might not be a useful technique for making diagnosis of ENKTL.</p

    Primary hyperparathyroidism diagnosed after surgical ablation of a costal mass mistaken for giant-cell bone tumor: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Primary hyperparathyroidism is a common endocrine disorder characterized by elevated parathyroid hormone levels, which cause continuous osteoclastic bone resorption. Giant cell tumor of bone is an expansile osteolytic tumor that contains numerous osteoclast-like giant cells. There are many similarities in the radiological and histological features of giant cell tumor of bone and brown tumor. This is a rare benign focal osteolytic process most commonly caused by hyperparathyroidism.</p> <p>Case presentation</p> <p>We report the unusual case of a 40-year-old Caucasian woman in which primary hyperparathyroidism was diagnosed after surgical ablation of a costal mass. The mass was suspected of being neoplastic and histopathology was compatible with a giant cell tumor of bone. On the basis of the biochemical results (including serum calcium, phosphorous and intact parathyroid hormone levels) primary hyperparathyroidism was suspected and a brown tumor secondary to refractory hyperparathyroidism was diagnosed.</p> <p>Conclusions</p> <p>Since giant cell tumor is a bone neoplasm that has major implications for the patient, the standard laboratory tests in patients with bone lesions are important for a correct diagnosis.</p

    On the general theory of the origins of retroviruses

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    <p>Abstract</p> <p>Background</p> <p>The order retroviridae comprises viruses based on ribonucleic acids (RNA). Some, such as HIV and HTLV, are human pathogens. Newly emerged human retroviruses have zoonotic origins. As far as has been established, both repeated infections (themselves possibly responsible for the evolution of viral mutations <b>(Vm) </b>and host adaptability <b>(Ha)</b>); along with interplay between <it>inhibitors </it>and <it>promoters </it>of cell tropism, are needed to effect retroviral cross-species transmissions. However, the exact <it>modus operadi </it>of intertwine between these factors at molecular level remains to be established. Knowledge of such intertwine could lead to a better understanding of retrovirology and possibly other infectious processes. This study was conducted to derive the mathematical equation of a general theory of the origins of retroviruses.</p> <p>Methods and results</p> <p>On the basis of an arbitrarily non-Euclidian geometrical "thought experiment" involving the cross-species transmission of simian foamy virus (sfv) from a non-primate species <it>Xy </it>to <it>Homo sapiens </it>(<it>Hs</it>), initially excluding all social factors, the following was derived. At the port of exit from <it>Xy </it>(where the species barrier, SB, is defined by the <it>Index of Origin</it>, IO), sfv shedding is (1) enhanced by two transmitting tensors <b>(Tt)</b>, (i) virus-specific immunity (VSI) and (ii) evolutionary defenses such as APOBEC, RNA interference pathways, and (when present) expedited therapeutics (denoted e<sup>2</sup>D); and (2) opposed by the five accepting scalars <b>(At)</b>: (a) genomic integration hot spots, gIHS, (b) nuclear envelope transit <b>(</b>NMt) vectors, (c) virus-specific cellular biochemistry, VSCB, (d) virus-specific cellular receptor repertoire, VSCR, and (e) pH-mediated cell membrane transit, (↓<sub>pH </sub>CMat). Assuming <b>As </b>and <b>Tt </b>to be independent variables, <b>IO = Tt/As</b>. The same forces acting in an opposing manner determine SB at the port of sfv entry (defined here by the <it>Index of Entry</it>, <b>IE = As/Tt</b>). Overall, If sfv encounters no unforeseen effects on transit between X<it>y </it>and <it>Hs</it>, then the square root of the combined index of sfv transmissibility (√<b>|RTI|) </b>is proportional to the product IO* IE (or ~Vm* Ha* ∑Tt*∑As*<b>Ω</b>), where <b>Ω </b>is the retrovirological constant and ∑ is a function of the ratio Tt/As or As/Tt for sfv transmission from <it>Xy </it>to <it>Hs</it>.</p> <p>Conclusions</p> <p>I present a mathematical formalism encapsulating the general theory of the origins of retroviruses. It summarizes the choreography for the intertwined interplay of factors influencing the probability of retroviral cross-species transmission: <b>Vm, Ha, Tt, As, </b>and <b>Ω</b>.</p

    Mda-9/Syntenin Is Expressed in Uveal Melanoma and Correlates with Metastatic Progression

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    Uveal melanoma is an aggressive cancer that metastasizes to the liver in about half of the patients, with a high lethality rate. Identification of patients at high risk of metastases may provide indication for a frequent follow-up for early detection of metastases and treatment. The analysis of the gene expression profiles of primary human uveal melanomas showed high expression of SDCBP gene (encoding for syndecan-binding protein-1 or mda-9/syntenin), which appeared higher in patients with recurrence, whereas expression of syndecans was lower and unrelated to progression. Moreover, we found that high expression of SDCBP gene was related to metastatic progression in two additional independent datasets of uveal melanoma patients. More importantly, immunohistochemistry showed that high expression of mda-9/syntenin protein in primary tumors was significantly related to metastatic recurrence in our cohort of patients. Mda-9/syntenin expression was confirmed by RT-PCR, immunofluorescence and immunohistochemistry in cultured uveal melanoma cells or primary tumors. Interestingly, mda-9/syntenin showed both cytoplasmic and nuclear localization in cell lines and in a fraction of patients, suggesting its possible involvement in nuclear functions. A pseudo-metastatic model of uveal melanoma to the liver was developed in NOD/SCID/IL2Rγ null mice and the study of mda-9/syntenin expression in primary and metastatic lesions revealed higher mda-9/syntenin in metastases. The inhibition of SDCBP expression by siRNA impaired the ability of uveal melanoma cells to migrate in a wound–healing assay. Moreover, silencing of SDCBP in mda-9/syntenin-high uveal melanoma cells inhibited the hepatocyte growth factor (HGF)-triggered invasion of matrigel membranes and inhibited the activation of FAK, AKT and Src. Conversely syntenin overexpression in mda-9/syntenin-low uveal melanoma cells mediated opposite effects. These results suggest that mda-9/syntenin is involved in uveal melanoma progression and that it warrants further investigation as a candidate molecular marker of metastases and a potential therapeutic target

    Genome-wide association studies of autoimmune vitiligo identify 23 new risk loci and highlight key pathways and regulatory variants

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    Vitiligo is an autoimmune disease in which depigmented skin results from the destruction of melanocytes1, with epidemiological association with other autoimmune diseases2. In previous linkage and genome-wide association studies (GWAS1 and GWAS2), we identified 27 vitiligo susceptibility loci in patients of European ancestry. We carried out a third GWAS (GWAS3) in European-ancestry subjects, with augmented GWAS1 and GWAS2 controls, genome-wide imputation, and meta-analysis of all three GWAS, followed by an independent replication. The combined analyses, with 4,680 cases and 39,586 controls, identified 23 new significantly associated loci and 7 suggestive loci. Most encode immune and apoptotic regulators, with some also associated with other autoimmune diseases, as well as several melanocyte regulators. Bioinformatic analyses indicate a predominance of causal regulatory variation, some of which corresponds to expression quantitative trait loci (eQTLs) at these loci. Together, the identified genes provide a framework for the genetic architecture and pathobiology of vitiligo, highlight relationships with other autoimmune diseases and melanoma, and offer potential targets for treatment
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