101 research outputs found

    "Wet-to-Dry" Conformational Transition of Polymer Layers Grafted to Nanoparticles in Nanocomposite

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    The present communication reports the first direct measurement of the conformation of a polymer corona grafted around silica nano-particles dispersed inside a nanocomposite, a matrix of the same polymer. This measurement constitutes an experimental breakthrough based on a refined combination of chemical synthesis, which permits to match the contribution of the neutron silica signal inside the composite, and the use of complementary scattering methods SANS and SAXS to extract the grafted polymer layer form factor from the inter-particles silica structure factor. The modelization of the signal of the grafted polymer on nanoparticles inside the matrix and the direct comparison with the form factor of the same particles in solution show a clear-cut change of the polymer conformation from bulk to the nanocomposite: a transition from a stretched and swollen form in solution to a Gaussian conformation in the matrix followed with a compression of a factor two of the grafted corona. In the probed range, increasing the interactions between the grafted particles (by increasing the particle volume fraction) or between the grafted and the free matrix chains (decreasing the grafted-free chain length ratio) does not influence the amplitude of the grafted brush compression. This is the first direct observation of the wet-to-dry conformational transition theoretically expected to minimize the free energy of swelling of grafted chains in interaction with free matrix chains, illustrating the competition between the mixing entropy of grafted and free chains, and the elastic deformation of the grafted chains. In addition to the experimental validation of the theoretical prediction, this result constitutes a new insight for the nderstanding of the general problem of dispersion of nanoparticles inside a polymer matrix for the design of new nanocomposites materials

    Results and long-term patient satisfaction after gluteal augmentation with platelet-rich plasma-enriched autologous fat

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    BACKGROUND: Buttock augmentation is gaining increasing popularity in aesthetic surgery. The relatively high incidence of complications after silicone implant placement lead to the increased use of lipofilling techniques, yielding variable results with respect to graft take rate and long-term stability. Platelet-rich plasma (PRP) has been shown to have beneficial effects on wound healing and angiogenesis in the past. Therefore, we aimed at investigating the long-term results and patient satisfaction after PRP-enriched lipofilling for buttock augmentation. METHODS: Twenty-four bilateral gluteal augmentations with PRP-enriched autologous fat were performed. Additionally, contour shaping was achieved by liposuction of the adjacent zones. Post-operative results and complications were recorded, and satisfaction with buttock shape was estimated by a patient questionnaire. RESULTS: Mean follow-up time was 44Β months, and mean amount of transferred fat was 481Β cc for both sides. No seroma or hematoma formation, infection or liponecrosis were reported during the post-operative follow-up. Subjective patient satisfaction in general increased from preoperatively to 3Β months postoperatively and declined only slightly in the long-term course. Satisfaction levels in general were specific for each patient. Patient recovery was quick, and the majority of patients returned to work within 10Β days after surgery. CONCLUSIONS: PRP-enhanced lipofilling of the buttocks proved to be a safe procedure including a low complication rate and consistent results. However, subjective patient expectations have to be taken into account when choosing the indication. Further large volume studies are needed to elucidate the potential and benefit of PRP in this context. Level of Evidence: Level IV, therapeutic study

    Involvement of the Macrophage Migration Inhibitory Factor (MIF) in Lipedema

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    Lipedema is a chronic disorder that mainly affects women. It is often misdiagnosed, and its etiology remains unknown. Recent research indicates an accumulation of macrophages and a shift in macrophage polarization in lipedema. One known protein superfamily that contributes to macrophage accumulation and polarization is the macrophage migration inhibitory factor (MIF) family. MIF-1 and MIF-2 are ubiquitously expressed and also regulate inflammatory processes in adipose tissue. In this study, the expression of MIF-1, MIF-2 and CD74-a common receptor for both cytokines-was analyzed in tissue samples of 11 lipedema and 11 BMI-matched, age-matched and anatomically matched control patients using qPCR and immunohistochemistry (IHC). The mRNA expression of MIF-1 (mean 1.256;SD 0.303;p = 0.0485) and CD74 (mean 1.514;SD 0.397;p = 0.0097) were significantly elevated in lipedema patients, while MIF-2 expression was unaffected (mean 1.004;SD 0.358;p = 0.9718). The IHC analysis corroborated the results for CD74 expression on a cellular level. In conclusion, our results provide first evidence for a potential involvement of the MIF family, presumably via the MIF-1-CD74 axis, in lipedema

    Involvement of the Macrophage Migration Inhibitory Factor (MIF) in Lipedema

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    Lipedema is a chronic disorder that mainly affects women. It is often misdiagnosed, and its etiology remains unknown. Recent research indicates an accumulation of macrophages and a shift in macrophage polarization in lipedema. One known protein superfamily that contributes to macrophage accumulation and polarization is the macrophage migration inhibitory factor (MIF) family. MIF-1 and MIF-2 are ubiquitously expressed and also regulate inflammatory processes in adipose tissue. In this study, the expression of MIF-1, MIF-2 and CD74-a common receptor for both cytokines-was analyzed in tissue samples of 11 lipedema and 11 BMI-matched, age-matched and anatomically matched control patients using qPCR and immunohistochemistry (IHC). The mRNA expression of MIF-1 (mean 1.256; SD 0.303; p = 0.0485) and CD74 (mean 1.514; SD 0.397; p = 0.0097) were significantly elevated in lipedema patients, while MIF-2 expression was unaffected (mean 1.004; SD 0.358; p = 0.9718). The IHC analysis corroborated the results for CD74 expression on a cellular level. In conclusion, our results provide first evidence for a potential involvement of the MIF family, presumably via the MIF-1-CD74 axis, in lipedema

    Novel Blood Vascular Endothelial Subtype-Specific Markers in Human Skin Unearthed by Single-Cell Transcriptomic Profiling

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    Ample evidence pinpoints the phenotypic diversity of blood vessels (BVs) and site-specific functions of their lining endothelial cells (ECs). We harnessed single-cell RNA sequencing (scRNA-seq) to dissect the molecular heterogeneity of blood vascular endothelial cells (BECs) in healthy adult human skin and identified six different subpopulations, signifying arterioles, post-arterial capillaries, pre-venular capillaries, post-capillary venules, venules and collecting venules. Individual BEC subtypes exhibited distinctive transcriptomic landscapes associated with diverse biological pathways. These functionally distinct dermal BV segments were characterized by their unique compositions of conventional and novel markers (e.g., arteriole marker GJA5; arteriole capillary markers ASS1 and S100A4; pre-venular capillary markers SOX17 and PLAUR; venular markers EGR2 and LRG1), many of which have been implicated in vascular remodeling upon inflammatory responses. Immunofluorescence staining of human skin sections and whole-mount skin blocks confirmed the discrete expression of these markers along the blood vascular tree in situ, further corroborating BEC heterogeneity in human skin. Overall, our study molecularly refines individual BV compartments, whilst the identification of novel subtype-specific signatures provides more insights for future studies dissecting the responses of distinct vessel segments under pathological conditions

    Ion-Lithium Collision Dynamics Studied with a Laser-Cooled In-Ring Target

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    We present a novel experimental tool allowing for kinematically complete studies of break-up processes of laser-cooled atoms. This apparatus, the \u27MOTReMi,\u27 is a combination of a magneto-optical trap (MOT) and a reaction microscope (ReMi). Operated in an ion-storage ring, the new setup enables us to study the dynamics in swift ion-atom collisions on an unprecedented level of precision and detail. In the inaugural experiment on collisions with 1.5MeV/amu O8 +-Li the pure ionization of the valence electron as well as the ionization-excitation of the lithium target was investigated

    Staphylococcus spp.: incidΓͺncia e surtos.

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    Uma das Γ‘reas de atuação da Embrapa AgroindΓΊstria de Alimentos Γ© a seguranΓ§a dos alimentos. Os procedimentos relacionados Γ  seguranΓ§a dos alimentos envolvem anΓ‘lise de risco, princΓ­pio da precaução, rastreabilidade, responsabilidades para produtores e autoridades, tendo como objetivo reduzir riscos de origem alimentar, com um nΓ­vel adequado de proteção da SaΓΊde PΓΊblica e medidas de controle para garantir o fornecimento de alimentos seguros. Esta publicação pretende informar sobre a incidΓͺncia de bactΓ©rias patogΓͺnicas do gΓͺnero Staphylococcus em alimentos e a ocorrΓͺncia de surtos provocados por esse patΓ³geno. Dessa forma, fez-se um amplo levantamento da incidΓͺncia e ocorrΓͺncia de surtos por tipo de alimento e espΓ©cie de microrganismo envolvido, e por regiΓ£o do Brasil, que pode se tornar uma importante ferramenta para auxiliar uma eventual anΓ‘lise de risco. Destina-se a estudantes e profissionais das Γ‘reas de biomedicina, tecnologia de alimentos e responsΓ‘veis por polΓ­ticas pΓΊblicas, entre outros.1a edição. E-book (2015)

    MicroRNA Dysregulation in the Spinal Cord following Traumatic Injury

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    Spinal cord injury (SCI) triggers a multitude of pathophysiological events that are tightly regulated by the expression levels of specific genes. Recent studies suggest that changes in gene expression following neural injury can result from the dysregulation of microRNAs, short non-coding RNA molecules that repress the translation of target mRNA. To understand the mechanisms underlying gene alterations following SCI, we analyzed the microRNA expression patterns at different time points following rat spinal cord injury
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