Quantum-critical spin dynamics in quasi-one-dimensional antiferromagnets

By means of nuclear spin-lattice relaxation rate 1/T1, we follow the spin dynamics as a function of the applied magnetic field in two gapped one-dimensional quantum antiferromagnets: the anisotropic spin-chain system NiCl2-4SC(NH2)2 and the spin-ladder system (C5H12N)2CuBr4. In both systems, spin excitations are confirmed to evolve from magnons in the gapped state to spinons in the gapples Tomonaga-Luttinger-liquid state. In between, 1/T1 exhibits a pronounced, continuous variation, which is shown to scale in accordance with quantum criticality. We extract the critical exponent for 1/T1, compare it to the theory, and show that this behavior is identical in both studied systems, thus demonstrating the universality of quantum critical behavior

Anisotropy of Magnetic Interactions in the Spin-Ladder Compound (C5_5H12_{12}N)2_2CuBr4_4

Magnetic excitations in the spin-ladder material (C$_5$H$_{12}$N)$_2$CuBr$_4$ [BPCB] are probed by high-resolution multi-frequency electron spin resonance (ESR) spectroscopy. Our experiments provide a direct evidence for a biaxial anisotropy ($\sim 5\%$ of the dominant exchange interaction), that is in contrast to a fully isotropic spin-ladder model employed for this system previously. It is argued that this anisotropy in BPCB is caused by spin-orbit coupling, which appears to be important for describing magnetic properties of this compound. The zero-field zone-center gap in the excitation spectrum of BPCB, $\Delta_0/k_{B}=16.5$ K, is detected directly. Furthermore, an ESR signature of the inter-ladder exchange interactions is obtained. The detailed characterization of the anisotropy in BPCB completes the determination of the full spin hamiltonian of this exceptional spin-ladder material and shows ways to study anisotropy effects in spin ladders.Comment: 6 pages, 6 figure

Effects mediated by the α7 nicotinic acetylcholine receptor on cell proliferation and migration in rat adipose-derived stem cells

Adipose-derived stem cells (ASCs) are an attractive source for regenerative medicine as they can be easily iso-lated, rapidly expandable in culture and show excellent in vitro differentiation potential. Acetylcholine (ACh), one of the main neurotransmitters in central and peripheral nervous systems, plays key roles in the control of several physiological processes also in non-neural tissues. As demonstrated in our previous studies, ACh can contribute to the rat ASCs physiology, negatively modulating ASCs proliferation and migration via M2 mus-carinic receptor (mAChR) activation. In the present work we show that rat ASCs also express α7 nicotinic receptors (nAChRs). In particular, we have investigated the effects mediated by the selective activation of α7 nAChRs, which causes a reduction of ASC proliferation without affecting cell survival and morphology, and significantly promotes cell migration via upregulation of the CXCR4 expression. Interestingly, the activation of the α7 nAChR also upregulates the expression of M2 mAChR protein, indicating a cooperation between muscarinic and nicotinic receptors in the inhibition of ASC proliferation

Peptidomic approach for the identification of peptides with potential antioxidant and anti-hyperthensive effects derived from Asparagus by-products

Asparagus waste represents products of great interest since many compounds with high biological value are located in the lower portion of the spears. The extraction of bioactive compounds from asparagus by-products is therefore crucial for the purpose of adding value to these by-products. In this paper, bioactive peptides from asparagus waste were extracted, digested, purified and identified. In particular, Alcalase® was chosen as the enzyme to use to obtain protein hydrolysate due to its low cost and, consequently, the possibility of implementing the method on a large scale. In order to simplify the peptide extract to reach better identification, the hydrolysate was fractionated by reversed-phase chromatography in 10 fractions. Two tests were carried out for antioxidant activity (ABTS-DPPH) and one for antihypertensive activity (ACE). Fractions with a higher bioactivity score were identified by peptidomics technologies and screened for bioactivity with the use of bioinformatics. For ACE-inhibitor activity, two peptides were synthetized, PDWFLLL and ASQSIWLPGWL, which provided an EC50 value of 1.76 µmol L-1 and 4.02 µmol L-1, respectively. For the antioxidant activity, by DPPH assay, MLLFPM exhibited the lowest EC50 value at 4.14 µmol L-1, followed by FIARNFLLGW and FAPVPFDF with EC50 values of 6.76 µmol L-1 and 10.01 µmol L-1, respectively. A validation of the five identified peptides was also carried out. The obtained results showed that peptides obtained from asparagus by-products are of interest for their biological activity and are suitable for being used as functional ingredients

Empathy Measurement in Autism

Introduction A deficit in empathy is so often assumed in autistic individuals, that poor social outcomes are treated through empathy interventions without investigating other contributing factors. To target interventions to client needs, we need to determine whether an empathy intervention is required, or whether poor social outcomes are best improved through an alternative focus of support. Practitioners often overlook the fact that our understandings of empathy in autism are limited by the measures we use, and some do not evaluate client empathy at all, instead assuming a client will need an empathy intervention simply because they are autistic. Practitioners, therefore, need access to high quality empathy measures to determine whether an empathy intervention is the best approach for their autistic clients. The quality of these measures is paramount. Method A systematic literature review was conducted to examine the measurement properties of empathy self-reports used with both autistic and predominant neurotype adults. Articles were obtained from 7 databases, followed by ancestral searching for grey literature. I, an autistic researcher, will discuss how we critically evaluated the evidence for some of the most popular empathy measures, and will discuss the implications for research and practice. Results The systematic review obtained data on several empathy self-reports, including the Empathy Quotient and the Interpersonal Reactivity Index. Preliminary findings will be discussed, including how features such as poor reliability and non-literal language may bias the scores of autistic people. Discussion This study highlights gaps in our knowledge about measuring empathy in autistic adults and considers how these gaps affect our knowledge of empathy in the autistic population. Finally, I will propose solutions to improve empathy measurement for autistic adults. Improved measurement will help clinicians to determine where an empathy intervention is the best approach to supporting an autistic client with social difficulties

Therapeutical innovations and medical responsibility: What's new in oto-laryngology

On one hand the incessant and constant technological and instrumental progress in the medical fieldhas allowed to increase knowledge and to reach new objectives. On the other hand, however, it has also raised the risk linked to professional responsibility, regarding informed consent and law 24/2017 of the Italian Republic, better known as Gelli Bianco. In this work an analysis of relevant literature will be presented, followed by a study on the role of new devices on responsibility profiles in otolaryngology. According to the analysis of the Italian law and considering the weaknesses ofthe above mentioned guidelines, pending legal administrative clarifications, we believe an operational protocol can be proposed in case of application of therapeutical innovations, especially about experimental introductions. Consequently, in our opinion, the risk of incrimination persists in case of use of innovative procedures in the absence of a formal shared opinion expressed in guidelines or in good practices, which still need a satisfactory definition

The LRRK2 G2385R variant is a partial loss-of-function mutation that affects synaptic vesicle trafficking through altered protein interactions.

Mutations in the Leucine-rich repeat kinase 2 gene (LRRK2) are associated with familial Parkinson's disease (PD). LRRK2 protein contains several functional domains, including protein-protein interaction domains at its N- and C-termini. In this study, we analyzed the functional features attributed to LRRK2 by its N- and C-terminal domains. We combined TIRF microscopy and synaptopHluorin assay to visualize synaptic vesicle trafficking. We found that N- and C-terminal domains have opposite impact on synaptic vesicle dynamics. Biochemical analysis demonstrated that different proteins are bound at the two extremities, namely \u3b23-Cav2.1 at N-terminus part and \u3b2-Actin and Synapsin I at C-terminus domain. A sequence variant (G2385R) harboured within the C-terminal WD40 domain increases the risk for PD. Complementary biochemical and imaging approaches revealed that the G2385R variant alters strength and quality of LRRK2 interactions and increases fusion of synaptic vesicles. Our data suggest that the G2385R variant behaves like a loss-of-function mutation that mimics activity-driven events. Impaired scaffolding capabilities of mutant LRRK2 resulting in perturbed vesicular trafficking may arise as a common pathophysiological denominator through which different LRRK2 pathological mutations cause diseas