Mixed Metal & Polynuclear Complexes in Ti (IV)-Cu(II)-Tartrate System

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Non-cell autonomous OTX2 transcription factor regulates anxiety-related behaviors in the mouse

The Otx2 homeoprotein transcription factor is expressed in the dopaminergic neurons of the ventral tegmental area, a mesencephalic nucleus involved in the control of complex behaviors through its projections to limbic structures, including the ventral hippocampus, amygdala, nucleus accumbens and prefrontal cortex. We find adult mice heterozygous for Otx2 show a hypoanxious phenotype in light-dark box and elevated plus maze paradigms. However, the number of dopaminergic neurons, the integrity of their axons, their projection patterns in target structures, and the amounts of dopamine and dopamine metabolites in targets structures were not modified in the Otx2 mutant. Because OTX2 is expressed by the choroid plexus, secreted into cerebrospinal fluid and transferred to parvalbumin interneurons of the cortex, hippocampus, and amygdala, we investigated if the hypoanxiety of Otx2 heterozygous mice could result from the decreased synthesis of Otx2 in the choroid plexus. Indeed, hypoanxious phenotype was reversed by the overexpression of Otx2 specifically in choroid plexus of adult Otx2 heterozygous mice, while hypoanxious phenotype could be induced in adult wild type mice by lowering OTX2 levels in the cerebrospinal fluid. Taken together, OTX2 synthesis by the choroid plexus followed by its secretion into the cerebrospinal fluid is an important regulator of the anxiety phenotype in the mouse. All rights reserved. No reuse allowed without permission

Liquid Xenon Detectors for Positron Emission Tomography

PET is a functional imaging technique based on detection of annihilation photons following beta decay producing positrons. In this paper, we present the concept of a new PET system for preclinical applications consisting of a ring of twelve time projection chambers filled with liquid xenon viewed by avalanche photodiodes. Simultaneous measurement of ionization charge and scintillation light leads to a significant improvement to spatial resolution, image quality, and sensitivity. Simulated performance shows that an energy resolution of <10% (FWHM) and a sensitivity of 15% are achievable. First tests with a prototype TPC indicate position resolution <1 mm (FWHM).Comment: Paper presented at the International Nuclear Physics Conference, Vancouver, Canada, 201

Review: ‘Gimme five’: future challenges in multiple sclerosis. ECTRIMS Lecture 2009

This article is based on the ECTRIMS lecture given at the 25th ECTRIMS meeting which was held in Düsseldorf, Germany, from 9 to 12 September 2009. Five challenges have been identified: (1) safeguarding the principles of medical ethics; (2) optimizing the risk/benefit ratio; (3) bridging the gap between multiple sclerosis and experimental autoimmune encephalitis; (4) promoting neuroprotection and repair; and (5) tailoring multiple sclerosis therapy to the individual patient. Each of these challenges will be discussed and placed in the context of current research into the pathogenesis and treatment of multiple sclerosis

Genetic diversity analysis of Myristica and related genera using RAPD and ISSR markers

Genetic diversity among seven species of Myristica, two of its related genera and an unidentified species was analyzed using 46 PCR markers (30 RAPD and 16 ISSR). This is the first study on molecular genetic diversity of the rare, endangered and endemic Myristica species and its related genera. RAPD and ISSR analyses yielded 497 and 262 bands with 98.1% and 97.3% polymorphism, respectively. By combining markers, a total of 759 bands were detected of which 743 (97.8%) were polymorphic with an average of 16.1 bands per primer. High level of existing genetic variability was evident from the high percentage of polymorphism. Combined analysis of RAPD and ISSR markers resulted in better distinction of species. The mean polymorphic information content (PIC) indicated that both the marker systems are effective in detecting polymorphism either individually or in combination. Similarity coefficient (Jaccards) varied from 0.22 to 0.62 when markers were combined and the pattern was similar to RAPD with a high Mantel matrix correlation (r=0.95). Principal Coordinates Analysis (PCA) conformed to cluster analyses. First three most informative PC components explained 51.1%, 49.3% and 46.5% of total variation. A maximum similarity of (63%) was observed between Gymnocranthera canarica and the unidentified species of Myristica. Knema andamanica and Myristica prainii were found to be the most distinct (17.7%). Similarities at molecular level were close to either the morphological traits (mace and fruit/seed characters) or the geographical location. Species specific bands could be identified from all the accessions under study, which has the potential for development into SCAR (Sequence Characterised Amplified Region) markers for genotype fingerprinting or development of specific DNA probes for identification and authentication. &nbsp

Transition metal saccharide chemistry and biology: syntheses, characterization, solution stability and putative bio-relevant studies of iron-saccharide complexes

A number of Fe(III) complexes of saccharides and their derivatives, and those of ascorbic acid were synthesized, and characterized by a variety of analytical, spectral (FT-IR, UV-Vis, EPR, Mossbauer and EXAFS), magnetic and electrochemical techniques. Results obtained from various methods have shown good correlations. Data obtained from EPR, magnetic susceptibility and EXAFS techniques could be fitted well with the mono-, di- and trinuclear nature of the complexes. The solution stability of these complexes has been established using UV-Vis absorption and cyclic voltammetric techniques as a function of pH of the solution. Mixed valent, Fe(II,III) ascorbate complexes have also been synthesized and characterized. Reductive release of Fe(II) from the complexes using sodium dithionite has been addressed. In vitro absorption of Fe(III)-glucose complex has been studied using everted sacs of rat intestines and the results have been compared with that of simple ferric chloride. Fe(III)-saccharide complexes have shown regular protein synthesis even in hemin-deficient rabbit reticulocyte lysate indicating that these complexes play a role that is equivalent to that played by hemin in order to restore the normal synthesis of protein. These complexes have exhibited enhanced DNA cleavage properties in the presence of hydrogen peroxide with pUC-18 DNA plasmid

Mobility deficit – Rehabilitate, an opportunity for functionality

There are many pathological conditions that cause mobility deficits and that ultimately influence someone’s autonomy.Aims: to evaluate patients with mobility deficits functional status; to implement a Rehabilitation Nursing intervention plan; to monitor health gains through mobility deficits rehabilitation.Conclusion: Early intervention and the implementation of a nursing rehabilitation intervention plan results in health gains (direct or indirect), decreases the risk of developing Pressure Ulcers (PU) and the risk of developing a situation of immobility that affects patients’ autonomy and quality of life

First examples of neutral and cationic indenyl nickel(II) complexes bearing arsine or stibine ligands: highly active catalysts for the oligomerisation of styrene

New indenyl nickel(II) complexes bearing arsine or stibine ligands synthesised by a new methodology exhibit very high catalytic activities for the oligomerisation of styrene

A microchip optomechanical accelerometer

The monitoring of accelerations is essential for a variety of applications ranging from inertial navigation to consumer electronics. The basic operation principle of an accelerometer is to measure the displacement of a flexibly mounted test mass; sensitive displacement measurement can be realized using capacitive, piezo-electric, tunnel-current, or optical methods. While optical readout provides superior displacement resolution and resilience to electromagnetic interference, current optical accelerometers either do not allow for chip-scale integration or require bulky test masses. Here we demonstrate an optomechanical accelerometer that employs ultra-sensitive all-optical displacement read-out using a planar photonic crystal cavity monolithically integrated with a nano-tethered test mass of high mechanical Q-factor. This device architecture allows for full on-chip integration and achieves a broadband acceleration resolution of 10 \mu g/rt-Hz, a bandwidth greater than 20 kHz, and a dynamic range of 50 dB with sub-milliwatt optical power requirements. Moreover, the nano-gram test masses used here allow for optomechanical back-action in the form of cooling or the optical spring effect, setting the stage for a new class of motional sensors.Comment: 16 pages, 9 figure