SERS active nanoparticles were labeled with a reporter molecule and conjugated with anti-EpCAM antibodies. These immuno SERS markers were mixed with leukocytes, MCF-7 breast cancer cells and ...polystyrene beads, and the mixture was injected into a microfluidic quartz chip. Raman spectra were acquired at 785 nm excitation with 25 milliseconds exposure time in a continuous flow regime. Spectral unmixing by N-FINDR identified spectral signatures of SERS-labelled cells and polystyrene beads. This approach demonstrated rapid and reproducible SERS-assisted cell detection. Strategies are discussed to further increase the throughput for cell sorting.
SERS active nanoparticles were labeled with a reporter molecule and conjugated with anti-EpCAM antibodies.
Neuroinflammation contributes to neuronal degeneration in Parkinson's disease (PD). However, how brain inflammatory factors mediate the progression of neurodegeneration is still poorly understood. ...Experimental models of PD have shed light on the understanding of this phenomenon, but the exploration of inflammation-driven models is necessary to better characterize this aspect of the disorder. The use of lipopolysaccharide (LPS) to induce a neuroinflammation-mediated neuronal loss is useful to induce reliable elimination of dopaminergic neurons. Nevertheless, how this model parallels the PD-like neuroinflammation is uncertain. In the present work, we used the direct LPS injection as a model inductor to eliminate dopaminergic neurons of the substantia nigra pars compacta (SNpc) in rats and reevaluated the inflammatory reaction. High-resolution 3D histological examination revealed that, although LPS induced a reliable elimination of SNpc dopaminergic neurons, it also generated a massive inflammatory response. This inflammation-mediated injury was characterized by corralling, a damaged parenchyma occupied by a vast population of lesion-associated microglia and macrophages (LAMMs) undertaking wound compaction and scar formation, surrounded by highly reactive astrocytes. LAMMs tiled the entire lesion and engaged in long-standing phagocytic activity to resolve the injury. Additionally, modeling LPS inflammation in a cell culture system helped to understand the role of phagocytosis and cytotoxicity in the initial phases of dopaminergic degeneration and indicated that LAMM-mediated toxicity and phagocytosis coexist during LPS-mediated dopaminergic elimination. However, this type of severe inflammatory-mediated injury, and subsequent resolution appear to be different from the ageing-related PD scenario where the architectural structure of the parenchyma is mostly preserved. Thus, the necessity to explore new experimental models to properly mimic the inflammatory compound observed in PD degeneration.
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•LPS-induced mesencephalic injury causes corralling of microglia/macrophages•LPS-mediated lesion in SNpc triggers microglia/macrophages tiling and honeycomb structures•Microglia/macrophages tiling contributes to promote interactions with remnant dopaminergic neurons and debris•Corralled lesion shows high phagocytic capacity of dopaminergic remains
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The Ssp1 calmodulin kinase kinase (CaMKK) is necessary for stress-induced re-organization of the actin cytoskeleton and initiation of growth at the new cell end following division in ...Schizosaccharomyces pombe. In addition, it regulates AMP-activated kinase and functions in low glucose tolerance. ssp1− cells undergo mitotic delay at elevated temperatures and G2 arrest in the presence of additional stressors. Following hyperosmotic stress, Ssp1-GFP forms transient foci which accumulate at the cell membrane and form a band around the cell circumference, but not co-localizing with actin patches. Hyperosmolarity-induced localization to the cell membrane occurs concomitantly with a reduction of its interaction with the 14-3-3 protein Rad24, but not Rad25 which remains bound to Ssp1. The loss of rad24 in ssp1− cells reduces the severity of hyperosmotic stress response and relieves mitotic delay. Conversely, overexpression of rad24 exacerbates stress response and concomitant cell elongation. rad24− does not impair stress-induced localization of Ssp1 to the cell membrane, however this response is almost completely absent in cells overexpressing rad24.
The cyclic nucleotide second messengers cAMP and cGMP each affect virtually all cellular processes. Although these hydrophilic small molecules readily diffuse throughout cells, it is remarkable that ...their ability to activate their multiple intracellular effectors is spatially and temporally selective. Studies have identified a critical role for compartmentation of the enzymes which hydrolyse and metabolically inactivate these second messengers, the PDEs (cyclic nucleotide phosphodiesterases), in this specificity. In the present article, we describe several examples from our work in which compartmentation of selected cAMP- or cGMP-hydrolysing PDEs co-ordinate selective activation of cyclic nucleotide effectors, and, as a result, selectively affect cellular functions. It is our belief that therapeutic strategies aimed at targeting PDEs within these compartments will allow greater selectivity than those directed at inhibiting these enzymes throughout the cells.
Recently, a simple common-path, two-color interferometer has been used for Doppler-free saturated dispersion spectroscopy of iodine. We have used such a set-up to stabilize a Nd:YAG laser for the ...first time, to our knowledge. This method requires only a small number of low-cost optical components compared to frequency modulation techniques.We have measured a root Allan variance of 5 . 10(-12) for 0.2 s, and below 5 . 10 (-11) for integration times up to 300 s.
We have shown that pump light intensity stabilisation of a single-mode laser diode pumped Nd:YAG non-planar ring oscillator (NPRO) results in significant intensity noise reduction of the NPRO, as ...well as frequency noise suppression in the same order of magnitude. This effect does not occur in conventional laser diode array pumped NPROs due to mode beating effects originating in the multi-mode pump. As opposed to individual intensity and frequency stabilisation, pump light stabilisation contributes a simplified stabilisation scheme for single-mode laser diode pumped NPROs for high precision applications.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Blood flow-associated fluid shear stress (FSS) dynamically regulates the endothelium's ability to control arterial structure and function. While arterial endothelial cells (AEC) subjected to high ...levels of laminar FSS express a phenotype resistant to vascular insults, those exposed to low levels of laminar FSS, or to the FSS associated with oscillatory blood flow, are less resilient. Despite numerous reports highlighting how the cAMP-signaling system controls proliferation, migration and permeability of human AECs (HAECs), its role in coordinating HAEC responses to FSS has received scant attention. Herein we show that the cAMP effector EPAC1 is required for HAECs to align and elongate in the direction of flow, and for the induction of several anti-atherogenic and anti-thrombotic genes associated with these events. Of potential therapeutic importance, EPAC1 is shown to play a dominant role the in response of HAECs to low levels of laminar FSS, such as would be found within atherosclerosis-prone areas of the vasculature. Moreover, we show that EPAC1 promotes these HAEC responses to flow by regulating Vascular Endothelial Growth Factor Receptor-2 and Akt activation, within a VE-cadherin (VECAD)/PECAM1-based mechanosensor. We submit that these findings are consistent with the novel proposition that promoting EPAC1-signaling represents a novel means through which to promote expression of an adaptive phenotype in HAECs exposed to non-adaptive FSS-encoded signals as a consequence of vascular disease.
•EPAC1 activation enhances HAEC alignment and elongation under low FSS.•Knockdown of EPAC1 impairs HAEC morphological adaptations to low FSS and reduces the expression of flow-dependent genes.•EPAC1 mediates PECAM1/VEGFR2/VECAD mechanosensory complex assembly in HAECs.•VEGFR2 mechanosensor signaling to AKT is impaired in cells with reduced EPAC1 levels.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Non-resonant frequency conversion into the blue, green, orange, and red spectral regions is reported. Fundamental light sources were continuous-wave non-planar monolithic single-mode ring ...Nd{/content/MKWYC7N1PQBUTD6P/xxlarge8201.gif}:{/content/MKWYC7N1PQ B UTD6P/xxlarge8201.gif}YAG lasers as well as a standing-wave multi-mode Nd{/content/MKWYC7N1PQBUTD6P/xxlarge8201.gif}:{/content/MKWYC7N1PQ B UTD6P/xxlarge8201.gif}YAG laser. Periodically poled KTiOPO4 was employed as the nonlinear medium, but the considerations could also be applied to other periodically poled materials. A multi-pass scheme resulted in a normalized conversion efficiency as high as 27.2 %{/content/MKWYC7N1PQBUTD6P/xxlarge8201.gif}W for frequency doubling in the small-signal regime at 1064 nm.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Power scaling of diode-pumped monolithic Nd:YAG ring lasers to a single-frequency output power of nearly 2 W in cw operation is demonstrated by using a new ring laser design and applying four 1 W ...diode lasers. Coherent superposition of the radiation from two miniature ring lasers is achieved by injection locking of these systems.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
RNA‐dependent RNA polymerase activity is required for RNA interference (RNAi) in many lower eukaryotes including the fission yeast Schizosacchromyces pombe. Together with Ago1 and Dcr1, the ...RNA‐dependent RNA polymerase Rdp1 is critical for RNA‐dependent transcriptional‐ and post‐transcriptional gene silencing. Although the bulk of Rdp1 is localized to the nucleus, Ago1 and Dcr1 are primarily cytoplasmic. This may reflect the fact that Rdp1 is required early in the RNAi pathway to generate double strand RNA from transcripts that originate from centromeric loci. The relatively large size of Rdp1 (139.4 kD) precludes passive diffusion of the enzyme into the nucleus suggesting that karyopherin‐dependent transport is involved in nuclear targeting of this enzyme. In this study, we report that the karyopherin/importin β3 homolog Sal3 is required for nuclear import of Rdp1 in S. pombe. Loss of nuclear Rdp1 was associated with substantially reduced transcriptional gene silencing, and surprisingly, post‐transcriptional gene silencing which occurs in the cytoplasm of other eukaryotes, was also significantly affected. Together, these results identify Sal3 as a modulator of RNAi‐dependent transcriptional gene silencing as well as a potential link between nuclear import and post‐transcriptional gene silencing.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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