3,594 research outputs found

    Optical eigenmode imaging

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    We present an indirect imaging method that measures both amplitude and phase information from a transmissive target. Our method is based on an optical eigenmode decomposition of the light intensity and the first-order cross correlation between a target field and these eigenmodes. We demonstrate that such optical eigenmode imaging does not need any a priori knowledge of the imaging system and corresponds to a compressive full-field sampling leading to high image extraction efficiencies. Finally, we discuss the implications with respect to second-order correlation imaging

    Advanced Label-Free Optical Methods for Spermatozoa Quality Assessment and Selection

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    Current in vitro fertilization (IVF) techniques require a severe selection of sperm, generally based on concentration, morphology, motility, and DNA integrity. Since routinely separation methods may damage the viability of the sperm cell, there is a growing interest in providing a method for noninvasively analyzing spermatozoa taking into account all those parameters. This chapter first reviews the state-of-the-art of label-free sperm cell imaging for IVF, highlighting the limitations of the used techniques. Then, our innovative approach combining Raman spectroscopy and digital holography will be described and its advantages detailed. These include the ability to perform a simultaneous and correlative morphological and biochemical analysis of sperm cells, without labeling, in a fast and reliable way. Finally, the difficulty in reaching clinical use will be discussed, as well as the possible solutions offered by new technological improvements

    SERS Quantification of Galunisertib Delivery in Colorectal Cancer Cells by Plasmonic-Assisted Diatomite Nanoparticles

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    AbstractThe small molecule Galunisertib (LY2157299, LY) shows multiple anticancer activities blocking the transforming growth factor‐β1 receptor, responsible for the epithelial‐to‐mesenchymal transition (EMT) by which colorectal cancer (CRC) cells acquire migratory and metastatic capacities. However, frequent dosing of LY can produce highly toxic metabolites. Alternative strategies to reduce drug side effects can rely on nanoscale drug delivery systems that have led to a medical revolution in the treatment of cancer, improving drug efficacy and lowering drug toxicity. Here, a hybrid nanosystem (DNP‐AuNPs‐LY@Gel) made of a porous diatomite nanoparticle decorated with plasmonic gold nanoparticles, in which LY is retained by a gelatin shell, is proposed. The multifunctional capability of the nanosystem is demonstrated by investigating the efficient LY delivery, the enhanced EMT reversion in CRCs and the intracellular quantification of drug release with a sub‐femtogram resolution by surface‐enhanced Raman spectroscopy (SERS). The LY release trigger is the pH sensitivity of the gelatin shell to the CRC acidic microenvironment. The drug release is real‐time monitored at single‐cell level by analyzing the SERS signals of LY in CRC cells. The higher efficiency of LY delivered by the DNP‐AuNPs‐LY@Gel complex paves the way to an alternative strategy for lowering drug dosing and consequent side effects

    Innate Memory Reprogramming by Gold Nanoparticles Depends on the Microbial Agents That Induce Memory

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    Inmunidad innata; Agentes microbianos; NanopartículasInnate immunity; Microbial agents; NanoparticlesImmunitat innata; Agents microbians; NanopartículesInnate immune memory, the ability of innate cells to react in a more protective way to secondary challenges, is induced by exposure to infectious and other exogeous and endogenous agents. Engineered nanoparticles are particulate exogenous agents that, as such, could trigger an inflammatory reaction in monocytes and macrophages and could therefore be also able to induce innate memory. Here, we have evaluated the capacity of engineered gold nanoparticles (AuNPs) to induce a memory response or to modulate the memory responses induced by microbial agents. Microbial agents used were in soluble vs. particulate form (MDP and the gram-positive bacteria Staphylococcus aureus; β-glucan and the β-glucan-producing fungi C. albicans), and as whole microrganisms that were either killed (S. aureus, C. albicans) or viable (the gram-negative bacteria Helicobacter pylori). The memory response was assessed in vitro, by exposing human primary monocytes from 2-7 individual donors to microbial agents with or without AuNPs (primary response), then resting them for 6 days to allow return to baseline, and eventually challenging them with LPS (secondary memory response). Primary and memory responses were tested as production of the innate/inflammatory cytokine TNFι and other inflammatory and anti-inflammatory factors. While inactive on the response induced by soluble microbial stimuli (muramyl dipeptide -MDP-, β-glucan), AuNPs partially reduced the primary response induced by whole microorganisms. AuNPs were also unable to directly induce a memory response but could modulate stimulus-induced memory in a circumscribed fashion, limited to some agents and some cytokines. Thus, the MDP-induced tolerance in terms of TNFι production was further exacerbated by co-priming with AuNPs, resulting in a less inflammatory memory response. Conversely, the H. pylori-induced tolerance was downregulated by AuNPs only relative to the anti-inflammatory cytokine IL-10, which would lead to an overall more inflammatory memory response. These effects of AuNPs may depend on a differential interaction/association between the reactive particle surfaces and the microbial components and agents, which may lead to a change in the exposure profiles. As a general observation, however, the donor-to-donor variability in memory response profiles and reactivity to AuNPs was substantial, suggesting that innate memory depends on the individual history of exposures.This work was supported by the EU Commission H2020 projects PANDORA (GA 671881) and ENDONANO (GA 812661), the Italian MIUR InterOmics Flagship projects MEMORAT and MAME, the Italian MIUR/PRIN-20173ZECCM, the Priority program ACBN (Allergy Cancer BioNano Research Centre) of the University of Salzburg, the Cancer Cluster Salzburg, the Research Grant from the University of Salzburg, and the Austrian Science Fund (FWF) Grant Nr. P 29941

    Psychological adjustment and heart rate variability in ovarian cancer survivors

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    Introduction: Body image, posttraumatic growth, quality of life, coping, and social support are relevant concepts to ovarian cancer survivors. This study aimed to examine the associations among these concepts as well as their relationships with heart rate variability (HRV), which is an index of vagal tone. Methods: an exploratory and correlational study was conducted on 25 ovarian cancer survivors. We used self-report measures to assess psychological variables. HRV parameters recorded for this study were analyzed in the time domain and in the frequency domain. Spearman correlations were performed. Results: Positive attitude coping strategy was associated with psychological and physical distress related to problems of appearance (Rho = -.57, p < .01), emotional functioning (Rho = .53, p < .01), and global health (Rho = .47, p < .05). Problem solving coping strategy was correlated with a higher posttraumatic growth, namely greater personal strength (Rho = .44, p < .05) and better relationships with others (Rho = .40, p < .05). Seeking social support was associated with growth in relationships with others (Rho = .40, p < .05). Higher HRV parameters were associated with higher physical functioning (SDNN: Rho = .59, p < .01; RMSSD: Rho = .54; p < .01; pNN50: Rho = .56, p < .01; HF: Rho = .58, p < .01). The ratio of low-frequency to high-frequency power (LF/HF) was negatively associated with posttraumatic growth (i.e., personal strength: Rho = .51, p < .05; new possibilities: Rho = -.54, p < .01). Discussion: Positive attitude and problem solving coping strategies may facilitate psychological adjustment to ovarian cancer. The strong association between markers of vagal tone and physical functioning offers insights on the possible role of vagus nerve in ovarian cancer survivors. These findings should be further investigated by future studies with larger samples and longitudinal designs

    Quantitative assessment of non-conservative radiation forces in an optical trap

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    The forces acting on an optically trapped particle are usually assumed to be conservative. However, the presence of a non-conservative component has recently been demonstrated. Here we propose a technique that permits one to quantify the contribution of such non-conservative component. This is an extension of a standard optical tweezers calibration technique and, therefore, can easily become a standard test to verify the conservative optical force assumption. Using this technique we have analyzed different-sized optically trapped particles under different trapping conditions. We conclude that the non-conservative effects are effectively negligible and do not affect the standard calibration procedure, unless for extremely low-power trapping, far away from the trapping regimes usually used in experiments.Comment: 8 pages, 4 figures; Europhys. Lett. (EPL) (2009), accepte

    COVID-19 And Breast Fine Needle Aspiration Cytology Method: What Should We Change?

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    Air-dried slide preparation for fine needle aspiration cytology procedures, is currently considered unsafe because of the risk of infectious aerosols of Coronavirus 19. This study compares the safety and accuracy of two different protocols, one with and one without air-dried slides

    Interplay Between SIRT-3, Metabolism and Its Tumor Suppressor Role in Hepatocellular Carcinoma

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    Sirtuins (SIRT), first described as nicotinamide adenine dinucleotide (NAD + )-dependent type III histone deacetylases, are produced by cells to support in the defense against chronic stress conditions such as metabolic syndromes, neurodegeneration, and cancer. SIRT-3 is one of the most studied members of the mitochondrial sirtuins family. In particular, its involvement in metabolic diseases and its dual role in cancer have been described. In the present review, based on the evidence of SIRT-3 involvement in metabolic dysfunctions, we aimed to provide an insight into the multifaceted role of SIRT-3 in many solid and hematological tumors with a particular focus on hepatocellular carcinoma (HCC). SIRT-3 regulatory effect and involvement in metabolism dysfunctions may have strong implications in HCC development and treatment. Research literature widely reports the relationship between metabolic disorders and HCC development. This evidence suggests a putative bridge role of SIRT-3 between metabolic diseases and HCC. However, further studies are necessary to demonstrate such interconnection
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