Sulfur Metabolism and Sulfur-Containing Amino Acids: I- Molecular Effectors

The biology of the macro-element sulfur (S) is attracting an ever growing attention concerning cell physiology and human health. Sulfur metabolism works at the interplay between genetics and epigenetic as well as in the maintain of cell redox homeostasis. Indeed, unbalanced levels of S compounds in the body are actually under investigation as vulnerability factors and/or indicators of impaired cell oxidation state in a variety of human diseases. The purpose of this article is to overview some main S metabolic pathways in humans and their relevance in cell physiology and pathology. Since S is an essential nutrient for life, we first present its distribution and significance in the biosphere, focusing then on S metabolic fluxes which encompass S-containing amino acids (S-AAs), as well as sulfoconjugation, the synthesis and release of H2S together the formation of iron-sulfur cluster proteins. Despite the vastness of the topic, we would like to emphasize herein that the study of S networks in human pathology, especially in complex, multi-factorial disorders, deserves greater impulsion and deepening

Jasmonic acid methyl ester induces xylogenesis and modulates auxin-induced xylary cell identity with NO Involvement

In Arabidopsis basal hypocotyls of dark-grown seedlings, xylary cells may form from the pericycle as an alternative to adventitious roots. Several hormones may induce xylogenesis, as Jasmonic acid (JA), as well as indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) auxins, which also affect xylary identity. Studies with the ethylene (ET)-perception mutant ein3eil1 and the ET-precursor 1-aminocyclopropane-1-carboxylic acid (ACC), also demonstrate ET involvement in IBA-induced ectopic metaxylem. Moreover, nitric oxide (NO), produced after IBA/IAA-treatments, may affect JA signalling and interact positively/negatively with ET. To date, NO-involvement in ET/JA-mediated xylogenesis has never been investigated. To study this, and unravel JA-effects on xylary identity, xylogenesis was investigated in hypocotyls of seedlings treated with JA methyl-ester (JAMe) with/without ACC, IBA, IAA. Wild-type (wt) and ein3eil1 responses to hormonal treatments were compared, and the NO signal was quantified and its role evaluated by using NO-donors/scavengers. Ectopic-protoxylem increased in the wt only after treatment with JAMe(10 μM), whereas in ein3eil1 with any JAMe concentration. NO was detected in cells leading to either xylogenesis or adventitious rooting, and increased after treatment with JAMe(10 μM) combined or not with IBA(10 μM). Xylary identity changed when JAMe was applied with each auxin. Altogether, the results show that xylogenesis is induced by JA and NO positively regulates this process. In addition, NO also negatively interacts with ET-signalling and modulates auxin-induced xylary identity

The multiform motor cortical output: kinematic, predictive and response coding

Observing actions performed by others entails a subliminal activation of primary motor cortex reflecting the components encoded in the observed action. One of the most debated issues concerns the role of this output: Is it a mere replica of the incoming flow of information (kinematic coding), is it oriented to anticipate the forthcoming events (predictive coding) or is it aimed at responding in a suitable fashion to the actions of others (response coding)? The aim of the present study was to disentangle the relative contribution of these three levels and unify them into an integrated view of cortical motor coding. We combined transcranial magnetic stimulation (TMS) and electromyography recordings at different timings to probe the excitability of corticospinal projections to upper and lower limb muscles of participants observing a soccer player performing: (i) a penalty kick straight in their direction and then coming to a full stop, (ii) a penalty kick straight in their direction and then continuing to run, (iii) a penalty kick to the side and then continuing to run. The results show a modulation of the observer's corticospinal excitability in different effectors at different times reflecting a multiplicity of motor coding. The internal replica of the observed action, the predictive activation, and the adaptive integration of congruent and non-congruent responses to the actions of others can coexist in a not mutually exclusive way. Such a view offers reconciliation among different (and apparently divergent) frameworks in action observation literature, and will promote a more complete and integrated understanding of recent findings on motor simulation, motor resonance and automatic imitation

Spinning Solitons of a Modified Non-Linear Schroedinger equation

We study soliton solutions of a modified non-linear Schroedinger (MNLS) equation. Using an Ansatz for the time and azimuthal angle dependence previously considered in the studies of the spinning Q-balls, we construct multi-node solutions of MNLS as well as spinning generalisations.Comment: 8 Revtex pages, 5 ps figures; v2: minor change

Low-Power Instrument Transformers and Energy Meters: Opportunities and Obstacles

Low-Power Instrument Transformers (LPITs) are becoming the preferred measurement device in the medium voltage (MV) distribution network (DN). They have several benefits compared to legacy solutions. However, the adoption of LPITs results in the need for adapting the grid and its assets to accept them. One practical example is using LPITs as the current and voltage source for energy meters (EMs), which are also used for billing purposes. The resulting measurement chain introduces several metrological challenges that must be studied and investigated. Therefore, in this work, the scenarios of LPITs and energy meters are introduced along with the latest relevant international standards. Afterwards, the opportunities and obstacles due to the implementation of the LPIT plus energy meter measurement chain are discussed. The discussion focuses on metrological requirements, accuracy evaluation, target uncertainty, and influence quantities affecting the performance of the devices

Pycnogonids (Arthropoda: Pycnogonida) of Portofino, Ligurian Sea (North-Western Mediterranean Sea)

Pycnogonida collected monthly from September 2017 to August 2018 in the Portofino Marine Protected Area at 0\u20135 m depth were studied. A total of 499 specimens were collected, 457 of which were identified to species level. These were classified as belonging to 10 species: Achelia echinata*, Ascorhynchus castelli, Neotrygaeus communis*, Tanystylum conirostre*, Anoplodactylus angulatus, A. petiolatus, A. pygmaeus*, A. virescens, Callipallene phantoma and C. tiberi*. For five dominant species (those marked with an asterisk) the annual phenology was outlined. Four hundred and seventeen additional specimens, collected from the same area and depth range mainly during the 1970s and 1980s were identified to species level for completeness of information, leading to the addition of Pycnogonum pusillum and Endeis spinosa

Surface magnetic canting in a ferromagnet

The surface magnetic canting (SMC) of a semi-infinite film with ferromagnetic exchange interaction and competing bulk and surface anisotropies is investigated via a nonlinear mapping formulation of mean-field theory previously developed by our group [L. Trallori et al., Int. J. Mod. Phys. B 10, 1935-1988 (1996)], and extended to the case where an external magnetic field is applied to the system. When the field H is parallel to the film plane, the condition for SMC is found to be the same as that recently reported by Popov and Pappas [Phys. Rev. B 64, 184401 (2001)]. The case of a field H applied perpendicularly to the film plane is also investigated. In both cases, the zero-temperature equilibrium configuration is easily determined by our theoretical approach.Comment: 4 pages, 3 figure

Hydroxyindole-O-methyltransferase (HIOMT) activity in the retina of melatonin-proficient mice

Numerous pieces of evidence support the expression by the mammalian retina of Hydroxyindole-O-methyltransferase (HIOMT, EC 2.1.1.4), the enzyme directly responsible for the biosynthesis of the pineal chronobiotic hormone melatonin (MLT). However, conflicting results obtained so far by enzyme-kinetic and immune-detection techniques still make HIOMT presence and relevance in the eye a matter of debate. This work aimed at evaluating unambiguously HIOMT activity in the mouse retina, a valuable model for studying the effects of MLT variations on ocular pathophysiology. Since laboratory mouse strains can bear genetic polymorphisms yielding defective enzymes of MLT biosynthesis, retinas and control pineal glands used in this study were obtained in a MLT-proficient crossing of A/J mice, the A/J/C57BL/10 strain. To improve the radiochemical reference assay, we tested different homogenization procedures coupled with HPLC detection. Concomitantly, we quantified MLT, and its precursor N-acetyl-serotonin (NAS) by HPLC coupled to electrochemical detection in retinas isolated from either light- or dark-adapted mice. Results showed that the standard radio-chemical assay was successful for pineal HIOMT only, whereas specific homogenization buffers and HPLC were required to detect retinal activity, presumably due to interfering methyl-transferases inhibited by NAS. Under present conditions, retinal HIOMT Vmax accounted for by ≈ 40 fmol/h/mg protein, 2.6-hundreds-fold lower than the pineal counterpart, displaying equivalent KMs (≈10 μM). Moreover, NAS and MLT rapidly decreased in light-exposed isolated retinas, corroborating light-sensitive in-situ MLT formation. Conclusively, we measured mouse retinal HIOMT kinetics under basal conditions, a useful result to elucidate the regulatory patterns, the possible impact on eye health, and therapeutic approaches related to this enzyme