A Novel Method for Rapid Hybridization of DNA to a Solid Support

Here we present a novel approach entitled Magnetic Forced Hybridization (MFH) that provides the means for efficient and direct hybridization of target nucleic acids to complementary probes immobilized on a glass surface in less than 15 seconds at ambient temperature. In addition, detection is carried out instantly since the beads become visible on the surface. The concept of MFH was tested for quality control of array manufacturing, and was combined with a multiplex competitive hybridization (MUCH) approach for typing of Human Papilloma Virus (HPV). Magnetic Forced Hybridization of bead-DNA constructs to a surface achieves a significant reduction in diagnostic testing time. In addition, readout of results by visual inspection of the unassisted eye eliminates the need for additional expensive instrumentation. The method uses the same set of beads throughout the whole process of manipulating and washing DNA constructs prior to detection, as in the actual detection step itself.     

Age-related effect of aerobic exercise training on antioxidant and oxidative markers in the liver challenged by doxorubicin in rats

The aims of the current study were to investigate the oxidant and antioxidant status of liver tissue challenged by doxorubicin and to examine the possible protective effects of aerobic exercise on doxorubicin-induced oxidative stress. Seventy-two rats were divided into three age groups (Young, Adult, and Elderly) with three treatment subgroups consisting of eight rats per age group: doxorubicin, aerobic exercise?+?doxorubicin, and aerobic exercise?+?saline. The experimental groups performed regular treadmill running for 3 weeks. Doxorubicin was administered by i.p. injection at a dosage of 20?mg kg^?1 while the aerobic exercise?+?saline group received saline of a comparable volume. Heat shock protein 70, malondialdehyde, glutathione peroxidase, and protein carbonyl were determined from the liver homogenates following the intervention period. Treatment with doxorubicin induced hepatotoxicity in all groups with lower values of oxidative stress in young compared with the older groups. The inclusion of aerobic exercise training significantly increased heat shock protein 70 and antioxidant enzyme levels (glutathione peroxidase) whereas it decreased oxidative stress biomarkers (malondialdehyde and protein carbonyl) for all age groups. These results suggest that aerobic exercise training may be a potential, non-drug strategy to modulate doxorubicin-induced hepatotoxicity through its positive impact on antioxidant levels and oxidative stress biomarkers.     

ERRγ Preserves Brown Fat Innate Thermogenic Activity

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Unreduced gamete formation in wheat × <Emphasis Type="Italic">Aegilops</Emphasis> spp. hybrids is genotype specific and prevented by shared homologous subgenomes

Key message

The presence of homologous subgenomes inhibited unreduced gamete formation in wheat × Aegilops interspecific hybrids. Unreduced gamete rates were under the control of the wheat nuclear genome.

Abstract

Production of unreduced gametes is common among interspecific hybrids, and may be affected by parental genotypes and genomic similarity. In the present study, five cultivars of Triticum aestivum and two tetraploid Aegilops species (i.e. Ae. triuncialis and Ae. cylindrica) were reciprocally crossed to produce 20 interspecific hybrid combinations. These hybrids comprised two different types: T. aestivum × Aegilops triuncialis; 2n = ABDU^tC^t (which lack a common subgenome) and T. aestivum × Ae. cylindrica; 2n = ABDD^cC^c (which share a common subgenome). The frequency of unreduced gametes in F₁ hybrids was estimated in sporads from the frequency of dyads, and the frequency of viable pollen, germinated pollen and seed set were recorded. Different meiotic abnormalities recorded in the hybrids included precocious chromosome migration to the poles at metaphase I and II, laggards in anaphase I and II, micronuclei and chromosome stickiness, failure in cell wall formation, premature cytokinesis and microspore fusion. The mean frequency of restitution meiosis was 10.1 %, and the mean frequency of unreduced viable pollen was 4.84 % in T. aestivum × Ae. triuncialis hybrids. By contrast, in T. aestivum × Ae. cylindrica hybrids no meiotic restitution was observed, and a low rate of viable gametes (0.3 %) was recorded. This study present evidence that high levels of homologous pairing between the D and D^c subgenomes may interfere with meiotic restitution and the formation of unreduced gametes. Variation in unreduced gamete production was also observed between T. aestivum × Ae. triuncialis hybrid plants, suggesting genetic control of this trait.

     

Multiscale Investigation of Sodium-Ion Battery Anodes: Analytical Techniques and Applications

The anode/electrolyte interface behavior, and by extension, the overall cell performance of sodium-ion batteries is determined by a complex interaction of processes that occur at all components of the electrochemical cell across a wide range of size- and timescales. Single-scale studies may provide incomplete insights, as they cannot capture the full picture of this complex and intertwined behavior. Broad, multiscale studies are essential to elucidate these processes. Within this perspectives article, several analytical and theoretical techniques are introduced, and described how they can be combined to provide a more complete and comprehensive understanding of sodium-ion battery (SIB) performance throughout its lifetime, with a special focus on the interfaces of hard carbon anodes. These methods target various length- and time scales, ranging from micro to nano, from cell level to atomistic structures, and account for a broad spectrum of physical and (electro)chemical characteristics. Specifically, how mass spectrometric, microscopic, spectroscopic, electrochemical, thermodynamic, and physical methods can be employed to obtain the various types of information required to understand battery behavior will be explored. Ways are then discussed how these methods can be coupled together in order to elucidate the multiscale phenomena at the anode interface and develop a holistic understanding of their relationship to overall sodium-ion battery function.     

Comparative capability of menstrual blood versus bone marrow derived stem cells in neural differentiation

In order to characterize the potency of menstrual blood stem cells (MenSCs) for future cell therapy of neurological disorders instead of bone marrow stem cells (BMSCs) as a well-known and conventional source of adult stem cells, we examined the in vitro differentiation potential of these stem cells into neural-like cells. The differentiation potential of MenSCs to neural cells in comparison with BMSCs was assessed under two step neural differentiation including conversion to neurosphere-like cells and final differentiation. The expression levels of Nestin, Microtubule-associated protein 2, gamma-aminobutyric acid type B receptor subunit 1 and 2, and Tubulin, beta 3 class III mRNA and/or protein were up-regulated during development of MenSCs into neurosphere-like cells (NSCs) and neural-like cells. The up-regulation level of these markers in differentiated neural-like cells from MenSCs was comparable with differentiated cells from BMSCs. Moreover, both differentiated MenSCs and BMSCs expressed high levels of potassium, calcium and sodium channel genes developing functional channels with electrophysiological recording. For the first time, we demonstrated that MenSCs are a unique cell population with differentiation ability into neural-like cells comparable to BMSCs. In addition, we have introduced an approach to generate NSCs from MenSCs and BMSCs and their further differentiation into neural-like cells in vitro. Our results hold a promise to future stem cell therapy of neurological disorders using NSCs derived from menstrual blood, an accessible source in every woman.     

The C2 domain of SynGAP is essential for stimulation of the Rap GTPase reaction

The brain-specific synaptic guanosine triphosphatase (GTPase)-activating protein (SynGAP) is important in synaptic plasticity. It shows dual specificity for the small guanine nucleotide-binding proteins Rap and Ras. Here, we show that RapGAP activity of SynGAP requires its C2 domain. In contrast to the isolated GAP domain, which does not show any detectable RapGAP activity, a fragment comprising the C2 and GAP domains (C2-GAP) stimulates the intrinsic GTPase reaction of Rap by approximately 1 x 10(4). The C2-GAP crystal structure, complemented by modelling and biochemical analyses, favours a concerted movement of the C2 domain towards the switch II region of Rap to assist in GTPase stimulation. Our data support a catalytic mechanism similar to that of canonical RasGAPs and distinct from the canonical RapGAPs. SynGAP presents the first example, to our knowledge, of a GAP that uses a second domain for catalytic activity, thus pointing to a new function of C2 domains.     

A BAR domain-mediated autoinhibitory mechanism for RhoGAPs of the GRAF family

The BAR (Bin/amphiphysin/Rvs) domain defines an emerging superfamily of proteins implicated in fundamental biological processes by sensing and inducing membrane curvature. We identified a novel autoregulatory function for the BAR domain of two related GAPs' (GTPase-activating proteins) of the GRAF (GTPase regulator associated with focal adhesion kinase) subfamily. We demonstrate that the N-terminal fragment of these GAPs including the BAR domain interacts directly with the GAP domain and inhibits its activity. Analysis of various BAR and GAP domains revealed that the BAR domain-mediated inhibition of these GAPs' function is highly specific. These GAPs, in their autoinhibited state, are able to bind and tubulate liposomes in vitro, and to generate lipid tubules in cells. Taken together, we identified BAR domains as cis-acting inhibitory elements that very likely mask the active sites of the GAP domains and thus prevent down-regulation of Rho proteins. Most remarkably, these BAR proteins represent a dual-site system with separate membrane-tubulation and GAP-inhibitory functions that operate simultaneously.     

Lipid based nanoparticles containing saturated solution of NaCl, may be used to targeted eradication of cancerous cells

Different strategies used for treatment of cancer which has some major side effects. In this paper we hypothesized targeted delivery lipid based nanoparticles containing saturated solution of NaCl for elimination of cancerous cells.