26 research outputs found
Chromatin Remodeling Protein SMAR1 Is a Critical Regulator of T Helper Cell Differentiation and Inflammatory Diseases
T cell differentiation from naĂŻve T cells to specialized effector subsets of mature cells is determined by the iterative action of transcription factors. At each stage of specificT cell lineage differentiation, transcription factor interacts not only with nuclear proteins
such as histone and histone modifiers but also with other factors that are bound to the chromatin and play a critical role in gene expression. In this review, we focus on one
of such nuclear protein known as tumor suppressor and scaffold matrix attachment region-binding protein 1 (SMAR1) in CD4+ T cell differentiation. SMAR1 facilitates Th1
differentiation by negatively regulating T-bet expression via recruiting HDAC1–SMRT complex to its gene promoter. In contrast, regulatory T (Treg) cell functions are dependent
on inhibition of Th17-specific genes mainly IL-17 and STAT3 by SMAR1. Here, we discussed a critical role of chromatin remodeling protein SMAR1 in maintaining a fine-tuned
balance between effector CD4+ T cells and Treg cells by influencing the transcription factors during allergic and autoimmune inflammatory diseases
The evolutionary significance of polyploidy
Polyploidy, or the duplication of entire genomes, has been observed in prokaryotic and eukaryotic organisms, and in somatic and germ cells. The consequences of polyploidization are complex and variable, and they differ greatly between systems (clonal or non-clonal) and species, but the process has often been considered to be an evolutionary 'dead end'. Here, we review the accumulating evidence that correlates polyploidization with environmental change or stress, and that has led to an increased recognition of its short-term adaptive potential. In addition, we discuss how, once polyploidy has been established, the unique retention profile of duplicated genes following whole-genome duplication might explain key longer-term evolutionary transitions and a general increase in biological complexity
Il seicentesco erbario secco di Bressanone (Museo della Farmacia): una preziosa testimonianza delle piante coltivate nell'Orto medico di Padova
Si tratta di uno studio articolato su un raro erbario secco seicentesco, con identificazione delle piante raccolte
Dispersion and shape engineered plasmonic nanosensors
Biosensors based on the localized surface plasmon resonance (LSPR) of individual metallic nanoparticles promise to deliver modular, low-cost sensing with high-detection thresholds. However, they continue to suffer from relatively low sensitivity and figures of merit (FOMs). Herein we introduce the idea of sensitivity enhancement of LSPR sensors through engineering of the material dispersion function. Employing dispersion and shape engineering of chiral nanoparticles leads to remarkable refractive index sensitivities (1,091 nmRIU(-1) at lambda = 921 nm) and FOMs (>2,800 RIU-1). A key feature is that the polarization-dependent extinction of the nanoparticles is now characterized by rich spectral features, including bipolar peaks and nulls, suitable for tracking refractive index changes. This sensing modality offers strong optical contrast even in the presence of highly absorbing media, an important consideration for use in complex biological media with limited transmission. The technique is sensitive to surface-specific binding events which we demonstrate through biotin-avidin surface coupling
Magnetic Propulsion of Microswimmers with DNA-Based Flagellar Bundles
We show that DNA-based self-assembly can serve as a general and
flexible tool to construct artificial flagella of several micrometers
in length and only tens of nanometers in diameter. By attaching the
DNA flagella to biocompatible magnetic microparticles, we provide
a proof of concept demonstration of hybrid structures that, when rotated
in an external magnetic field, propel by means of a flagellar bundle,
similar to self-propelling peritrichous bacteria. Our theoretical
analysis predicts that flagellar bundles that possess a length-dependent
bending stiffness should exhibit a superior swimming speed compared
to swimmers with a single appendage. The DNA self-assembly method
permits the realization of these improved flagellar bundles in good
agreement with our quantitative model. DNA flagella with well-controlled
shape could fundamentally increase the functionality of fully biocompatible
nanorobots and extend the scope and complexity of active materials
Recommended from our members
Chromium Trihalides CrX3 (X = Cl, Br, I): Direct Deposition of Micro- and Nanosheets on Substrates by Chemical Vapor Transport
The experimental observation of intrinsic ferromagnetism in single layered chromium trihalides CrX3 (X = Cl, Br, I) has gained outstanding attention recently due to their possible implementation in spintronic devices. However, the reproducible preparation of highly crystalline chromium(III) halide nanolayers without stacking faults is still an experimental challenge. As chromium trihalides consist of adjacent layers with weak interlayer coupling, the preparation of ultrathin CrX3 nanosheets directly on substrates via vapor transport proves as an advantageous synthesis technique. It is demonstrated that vapor growth of ultrathin highly crystalline CrX3 micro- and nanosheets succeeds directly on yttrium stabilized zirconia substrates in a one-step process via chemical vapor transport (CVT) in temperature gradients of 100 K (600 °C → 500 °C for CrCl3 and 650 °C → 550 °C for CrBr3 or CrI3) without a need for subsequent delamination. Due to simulation results, optimization of synthesis conditions is realized and phase pure CrX3 nanosheets with thicknesses ≤25 nm are obtained via short term CVT. The nanosheets morphology, crystallinity, and phase purity are analyzed by several techniques, including microscopy, diffraction, and spectroscopy. Furthermore, a potential subsequent delamination technique is demonstrated to give fast access to CrX3 monolayers using the example of CrCl3. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei