The visual-gestural modality affords its users simultaneous movement of several independent articulators and thus lends itself to simultaneous encoding of information. Much research has focused on the fact that sign languages coordinate two manual articulators in addition to a range of non-manual articulators to present different types of linguistic information simultaneously, from phonological contrasts to inflection, spatial relations, and information structure. Children and adults acquiring a signed language arguably thus need to comprehend and produce simultaneous structures to a greater extent than individuals acquiring a spoken language.
View Article and Find Full Text PDFEcho phonology was originally proposed to account for obligatory coordination of manual and mouth articulations observed in several sign languages. However, previous research into the phenomenon lacks clear criteria for which components of movement can or must be copied when the articulators are so different. Nor is there discussion of which nonmanual articulators can echo manual movement.
View Article and Find Full Text PDFIntracerebral injection of brain extracts from Alzheimer's disease (AD) patients into appropriate mouse models was previously found to drastically accelerate the deposition of Aβ amyloid in the recipient animals indicating a prion-like activity. In this study we show that this prion-like activity can be also identified by using a cell culture model of Aβ plaque formation. Analysis of biochemical fractions of AD brain extract indicate that the seeding-activity correlated with the presence of Aβ peptide and Aβ-derived aggregates.
View Article and Find Full Text PDFThe triterpenoid acetyl-lupeolic acid (ac-LA) isolated from the oleogum resin of reduced the viability of a panel of cancer cell lines more efficiently than lupeol. There was no detectable intracellular conversion of ac-LA to lupeol and . In contrast to docetaxel, ac-LA did not induce selection of treatment-resistant cancer cells.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2016
We studied the combined effects of pressure (0.1-200 MPa) and temperature (22, 30, and 38 °C) on the catalytic activity of designed amyloid fibrils using a high-pressure stopped-flow system with rapid UV/Vis absorption detection. Complementary FT-IR spectroscopic data revealed a remarkably high pressure and temperature stability of the fibrillar systems.
View Article and Find Full Text PDFElectron tomography is an increasingly powerful method to study the detailed architecture of macromolecular complexes or cellular structures. Applied to amyloid deposits formed in a cell culture model of systemic amyloid A amyloidosis, we could determine the structural morphology of the fibrils directly in the deposit. The deposited fibrils are arranged in different networks, and depending on the relative fibril orientation, we can distinguish between fibril meshworks, fibril bundles, and amyloid stars.
View Article and Find Full Text PDFPolymorphism is a wide-spread feature of amyloid-like fibrils formed in vitro, but it has so far remained unclear whether the fibrils formed within a patient are also affected by this phenomenon. In this study we show that the amyloid fibrils within a diseased individual can vary considerably in their three-dimensional architecture. We demonstrate this heterogeneity with amyloid fibrils deposited within different organs, formed from sequentially non-homologous polypeptide chains and affecting human or animals.
View Article and Find Full Text PDFMacrophages are key regulators of innate and adaptive immune responses. Exposure to microenvironmental stimuli determines their polarization into proinflammatory M1 and anti-inflammatory M2 macrophages. M1 exhibit high expression of proinflammatory TNF-α and IL-1β, and M2 promote tissue repair, but likewise support tumor growth and cause immune suppression by expressing IL-10.
View Article and Find Full Text PDFNanoparticles of various shapes, sizes, and materials carrying different surface modifications have numerous technological and biomedical applications. Yet, the mechanisms by which nanoparticles interact with biological structures as well as their biological impact and hazards remain poorly investigated. Due to their large surface to volume ratio, nanoparticles usually exhibit properties that differ from those of bulk materials.
View Article and Find Full Text PDFActivation of the mammalian target of rapamycin (mTOR) has been implicated in anticancer drug resistance, type 2 diabetes, and aging. Here, we show that surface functionalization of polystyrene nanoparticles with amino groups (PS-NH2), but not with carboxyl groups (PS-COOH), induces G2 cell-cycle arrest and inhibition of proliferation in three leukemia cell lines. Besides, PS-NH2 inhibit angiogenesis and proliferation of leukemia cells xenografted onto the chick chorioallantoic membrane.
View Article and Find Full Text PDFSpecifically designed and functionalized nanoparticles hold great promise for biomedical applications. Yet, the applicability of nanoparticles is critically predetermined by their surface functionalization. Here we demonstrate that amino-functionalized polystyrene nanoparticles (PS-NH(2)) of ∼100 nm in diameter, but not carboxyl- or nonfunctionalized particles, trigger NLRP3 inflammasome activation and subsequent release of proinflammatory interleukin 1β (IL-1β) by human macrophages.
View Article and Find Full Text PDFTumor cell lines are often used as models for the study of nanoparticle-cell interactions. Here we demonstrate that carboxy (PS-COOH) and amino functionalized (PS-NH2) polystyrene nanoparticles of ∼100 nm in diameter are internalized by human macrophages, by undifferentiated and by PMA-differentiated monocytic THP-1 cells via diverse mechanisms. The uptake mechanisms also differed for all cell types and particles when analyzed either in buffer or in medium containing human serum.
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