209 research outputs found

    Influence of perineural invasion in predicting overall survival and disease-free survival in patients With locally advanced gastric cancer

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    Background The aim of the present study was to evaluate the prognostic significance of perineural invasion (PNI) in locally advanced gastric cancer patients who underwent D2 gastrectomy and adjuvant chemotherapy. Methods The records of a series of 103 patients undergoing D2 gastrectomy with curative intent combined with adjuvant chemotherapy from January 2004 to December 2014 were retrospectively reviewed. Results PNI was positive in 47 (45.6%) specimens. The 1-, 3-, and 5-year overall survival rates were 81%, 55%, and 42%, respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 76%, 57%, and 49%, respectively. A multivariate analysis showed that age number of positive lymph nodes, T stage, and PNI were independently associated with overall survival. Regarding DFS, the multivariate analysis showed that only PNI was independently associated with DFS. Conclusions PNI and T stage and positive lymph nodes are independent markers of poor prognosis in patients with gastric cancer. PNI should be incorporated in the postoperative staging system for planning follow-up after surgery and in our opinion to propose more aggressive postoperative therapies in PNI-positive patients

    Hydrodynamics is Needed to Explain Propulsion in Chemophoretic Colloidal Rafts

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    Active particles driven by a chemical reaction are the subject of intense research to date due to their rich physics, being intrinsically far from equilibrium, and their multiple technological applications. Recent attention in the field is now shifting towards exploring the fascinating dynamics of mixture of active and passive systems. Here we realize active colloidal rafts, composed of a single catalytic particle encircled by several shells of passive microspheres assembled via light activated, chemophoretic flow. We show that considering only diffusiophoresis can explain the cluster kinetics but not the cluster propulsion behavior. Thus, using the Lorenz reciprocal theorem, we show that propulsion emerges by considering hydrodynamics via the diffusioosmotic answer of the substrate to the generated chemophoretic flow. While diffusioosmotic flows are often relegate to a secondary role, our work demonstrates their importance to understand the rich physics of active catalytic systems

    High density InAlAs/GaAlAs quantum dots for non-linear optics in microcavities

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    Structural and optical properties of InAlAs/GaAlAs quantum dots grown by molecular beam epitaxy are studied using transmission electron microscopy, temperature- and time resolvedphotoluminescence. The control of the recombination lifetime (50 ps – 1.25 ns), and of the dot density (5.10−8 – 2.1011 cm−3) strongly suggest that these material systems can find wide applications in opto-electronic devices as focusing non linear dispersive materials as well as fast saturable absorbers

    Black lymph node in tattoo: an easy pitfall

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    Tattoo is one of the most popular body arts in the world. It may be considered as a sign of belonging to a particular community as well as an expression of masculinity. However, it may also have a mere aesthetic purpose. In the past, whereas tattooing was common for male military personnel, bourgeois society spurned it. Nowadays, it is estimated that more than 24% of American adults have at least a tattoo.1 It is trending so tattooing is increasing social acceptability. The practice is equally common in men and women. In Italy, this phenomenon is less extensive than in America. However, it is definitely on the rise if we compare it with the past. Tattooing is becoming extremely popular with adolescent

    Emergency abdominal surgery in the elderly: a ten-year experience

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    Planar AFM macro-probes to study the biomechanical properties of large cells and 3D cell spheroids

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    The ability to measure mechanical response of cells under applied load is essential for developing more accurate models of cell mechanics and mechanotransduction. Living cells have been mechanically investigated by several approaches. Among them, atomic force microscopy (AFM) is widely used thanks to its high versatility and sensitivity. In the case of large cells or 3D multicellular aggregates, standard AFM probes may not be appropriate to investigate the mechanical properties of the whole biological system. Owing to their size, standard AFM probes can compress only a single somatic cell or part of it. To fill this gap, we have designed and fabricated planar AFM macro-probes compatible with commercial AFM instruments. The probes are constituted of a large flat compression plate, connected to the chip by two flexible arms, whose mechanical characteristics are tuned for specific biological applications. As proof of concept, we have used the macro-probes to measure the viscoelasticity of large spherical biological systems, which have a diameter above 100 \u3bcm: human oocytes and 3D cell spheroids. Compression experiments are combined with visual inspection, using a side-view configuration imaging, which allows us to monitor the sample morphology during the compression and to correlate it with the viscoelastic parameters. Our measurements provide a quantitative estimate of the relaxation times of such biological systems, which are discussed in relation to data present in literature. The broad applicability of the AFM macro-probes can be relevant to study the biomechanical features in any biological process involving large soft materials. Statement of Significance: The understanding of the role of physical factors in defining cell and tissue functions requires to develop new methods or improve the existing ones to accurately measure the biomechanical properties. AFM is a sensitive and versatile tool to measure the mechanical features from single proteins to single cells. When cells or cell aggregates exceed few tens of microns, AFM suffers from limitations. On these biological systems the control of the contact area and the application of a precise uniform compression becomes crucial. A modification of the standard cantilevers fabrication allowed us obtaining AFM macro-probes, having large planar contact area and spring constant suitable for biological investigations. They were demonstrated valuable to characterize the mechanical properties of large hierarchical biological systems
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