9,780 research outputs found
Cannabinoids in the treatment of epilepsy: current status and future prospects
Cannabidiol (CBD) is one of the prominent phytocannabinoids found in Cannabis sativa, differentiating from Δ9-tetrahydrocannabinol (THC) for its non-intoxicating profile and its antianxiety/antipsychotic effects. CBD is a multi-target drug whose anti-convulsant properties are supposed to be independent of endocannabinoid receptor CB1 and might be related to several underlying mechanisms, such as antagonism on the orphan GPR55 receptor, regulation of adenosine tone, activation of 5HT1A receptors and modulation of calcium intracellular levels. CBD is a lipophilic compound with low oral bioavailability (6%) due to poor intestinal absorption and high first-pass metabolism. Its exposure parameters are greatly influenced by feeding status (ie, high fatcontaining meals). It is mainly metabolized by cytochrome P 450 (CYP) 3A4 and 2C19, which it strongly inhibits. A proprietary formulation of highly purified, plant-derived CBD has been recently licensed as an adjunctive treatment for Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS), while it is being currently investigated in tuberous sclerosis complex. The regulatory agencies’ approval was granted based on four pivotal double-blind, placebocontrolled, randomized clinical trials (RCTs) on overall 154 DS patients and 396 LGS ones, receiving CBD 10 or 20 mg/kg/day BID as active treatment. The primary endpoint (reduction in monthly seizure frequency) was met by both CBD doses. Most patients reported adverse events (AEs), generally from mild to moderate and transient, which mainly consisted of somnolence, sedation, decreased appetite, diarrhea and elevation in aminotransferase levels, the last being documented only in subjects on concomitant valproate therapy. The interaction between CBD and clobazam, likely due to CYP2C19 inhibition, might contribute to some AEs, especially somnolence, but also to CBD clinical effectiveness. Cannabidivarin (CBDV), the propyl analogue of CBD, showed anti-convulsant properties in pre-clinical studies, but a plant-derived, purified proprietary formulation of CBDV recently failed the Phase II RCT in patients with uncontrolled focal seizures
Fluorescence Spectroscopy for the Diagnosis of Endometritis in the Mare
By exploiting the PMN property to produce high quantities of oxygen peroxide to neutralize pathogens, the oxygen peroxide content of uterine cells was measured to diagnose endometritis. After preliminary in vitro studies in which endometrial cells from slaughtered mares were mixed with leukocytes from peripheral blood, endometrial samples were collected by uterine flushing from mares before insemination. Staining endometrial cells with H2DCF-DA was combined with hydroethidine to normalize the fluorescence intensity with the cellular content of the sample. Stained cell smears were assumed as the gold standard of endometritis, and based on this assay, the samples were considered positive (C+) and negative (C-) for endometritis. The amount and the turbidity of fluid recovered by uterine flushing were significantly (p < 0.01) higher in C+ than in C-. Moreover, the oxygen peroxide content of the endometrial cells was significantly higher in the C+ than in the C- group (6.31 ± 1.92 vs. 3.12 ± 1.26, p = 0.001). Using the value of 4.4 as the cutoff level of this fluorescence cytology assay, it was found that only one C- sample exceeded the cutoff level (false positives = 7.7%) while three C+ samples showed values below the cutoff level (false negative = 11.5%)
Preparation of the group III nitride thin films AlN, GaN, InN by direct and reactive pulsed laser ablation
The methods of preparation of the group III nitrides AlN, GaN, and InN by laser ablation (i.e. laser sputtering), is here reviewed including studies on their properties. The technique, concerns direct ablation of nitride solid targets by laser to produce a plume which is collected on a substrate. Alternatively nitride deposition is obtained as a result of laser ablation of the metal and subsequent reaction in anNH3atmosphere. Optical multichannel emission spectroscopic analysis, and time of flight (TOF) mass spectrometry have been applied forin situidentification of deposition precursors in the plume moving from the target. Epitaxial AlN, GaN, and InN thin films on various substrates have been grown. X-ray diffraction, scanning electron microscopy, have been used to characterise thin films deposited by these methods
Stallion Sperm Freezing with Different Extenders: Role of Antioxidant Activity and Nitric Oxide Production
: Sensitivity to freezing remains a critical issue in stallion semen cryopreservation procedures. To explore this topic in-depth, semen was collected from ten stallions, diluted with three different extenders, transported to the laboratory, and then centrifuged and frozen with four different extenders. We conducted analyses of sperm kinetics, mitochondrial membrane potential (MMP), and hydrogen peroxide content both before and after freezing. Additionally, we assessed antioxidant activity using the ABTS and FRAP methods and measured nitric oxide stable metabolites (NOx) in the blank extenders, seminal plasma, and extenders conditioned by spermatozoa before and after freezing. We found significant variability in the antioxidant activity and NOx content of the blank extenders and the seminal plasma. In the seminal plasma, ABTS-based antioxidant activity and NOx values were correlated with some sperm kinematic parameters and MMP in refrigerated semen, while no correlation was observed in frozen sperm parameters. Sperm function varied significantly between stallions but not between extenders, either before or after freezing. However, significant differences in antioxidant activities and NOx values were found among extenders conditioned following freezing. These results provide new insights into the factors contributing to the variability in individual stallions' tolerance to sperm freezing
The role of preclinical models in creatine transporter deficiency: Neurobiological mechanisms, biomarkers and therapeutic development
Creatine (Cr) Transporter Deficiency (CTD) is an X-linked metabolic disorder, mostly caused by missense mutations in the SLC6A8 gene and presenting with intellectual disability, autistic behavior, and epilepsy. There is no effective treatment for CTD and patients need lifelong assistance. Thus, the research of novel intervention strategies is a major scientific challenge. Animal models are an excellent tool to dissect the disease pathogenetic mechanisms and drive the preclinical development of therapeutics. This review illustrates the current knowledge about Cr metabolism and CTD clinical aspects, with a focus on mainstay diagnostic and therapeutic options. Then, we discuss the rodent models of CTD characterized in the last decade, comparing the phenotypes expressed within clinically relevant domains and the timeline of symptom development. This analysis highlights that animals with the ubiquitous deletion/mutation of SLC6A8 genes well recapitulate the early onset and the complex pathological phenotype of the human condition. Thus, they should represent the preferred model for preclinical efficacy studies. On the other hand, brain-and cell-specific conditional mutants are ideal for understanding the basis of CTD at a cellular and molecular level. Finally, we explain how CTD models might provide novel insight about the pathogenesis of other disorders, including cancer
Photochemical R2PI study of chirality and intermolecular forces in supersonic beam
One and two-color, mass selected R2PI spectra of theS1←S0transitions in the bare(+)-(R)- 1-phenyl-1-ethanol(ER) and its complexes with different solvent molecules (solv) (-)-(R)-2-butanol(BR) or(+)-(S)-2-butanol(BS), (—)-(R)-2-pentanol (TR) or(+)-(S)-2-pentanol(TS) and(-)-(R)-2-butylamine(AR) or(+)-(S)-2-butylamine(AS), have been recorded after a supersonic molecular beam expansion. The one-color R2PI excitation spectra of the diastereomeric complexes are characterized by significant shifts of their band origin relative to that of bareER. The extent and the direction of these spectral shifts are found to depend upon the structure and the configuration ofsolvand are attributed to different short-range interactions in the ground and excited states of the complexes. In analogy with other diastereomeric complexes, the phenomenological binding energy of the homochiral cluster is found to be greater than that of the heterochiral one. Preliminary measurements of excitation spectrum of(+)-(R)-1-Indanol(IR) is also reported
Towards the QFT on Curved Spacetime Limit of QGR. I: A General Scheme
In this article and a companion paper we address the question of how one
might obtain the semiclassical limit of ordinary matter quantum fields (QFT)
propagating on curved spacetimes (CST) from full fledged Quantum General
Relativity (QGR), starting from first principles. We stress that we do not
claim to have a satisfactory answer to this question, rather our intention is
to ignite a discussion by displaying the problems that have to be solved when
carrying out such a program. In the present paper we propose a scheme that one
might follow in order to arrive at such a limit. We discuss the technical and
conceptual problems that arise in doing so and how they can be solved in
principle. As to be expected, completely new issues arise due to the fact that
QGR is a background independent theory. For instance, fundamentally the notion
of a photon involves not only the Maxwell quantum field but also the metric
operator - in a sense, there is no photon vacuum state but a "photon vacuum
operator"! While in this first paper we focus on conceptual and abstract
aspects, for instance the definition of (fundamental) n-particle states (e.g.
photons), in the second paper we perform detailed calculations including, among
other things, coherent state expectation values and propagation on random
lattices. These calculations serve as an illustration of how far one can get
with present mathematical techniques. Although they result in detailed
predictions for the size of first quantum corrections such as the gamma-ray
burst effect, these predictions should not be taken too seriously because a)
the calculations are carried out at the kinematical level only and b) while we
can classify the amount of freedom in our constructions, the analysis of the
physical significance of possible choices has just begun.Comment: LaTeX, 47 p., 3 figure
Identification of Novel Pax8 Targets in FRTL-5 Thyroid Cells by Gene Silencing and Expression Microarray Analysis
The differentiation program of thyroid follicular cells (TFCs), by far the most abundant cell population of the thyroid gland, relies on the interplay between sequence-specific transcription factors and transcriptional coregulators with the basal transcriptional machinery of the cell. However, the molecular mechanisms leading to the fully differentiated thyrocyte are still the object of intense study. The transcription factor Pax8, a member of the Paired-box gene family, has been demonstrated to be a critical regulator required for proper development and differentiation of thyroid follicular cells. Despite being Pax8 well-characterized with respect to its role in regulating genes involved in thyroid differentiation, genomics approaches aiming at the identification of additional Pax8 targets are lacking and the biological pathways controlled by this transcription factor are largely unknown.To identify unique downstream targets of Pax8, we investigated the genome-wide effect of Pax8 silencing comparing the transcriptome of silenced versus normal differentiated FRTL-5 thyroid cells. In total, 2815 genes were found modulated 72 h after Pax8 RNAi, induced or repressed. Genes previously reported to be regulated by Pax8 in FRTL-5 cells were confirmed. In addition, novel targets genes involved in functional processes such as DNA replication, anion transport, kinase activity, apoptosis and cellular processes were newly identified. Transcriptome analysis highlighted that Pax8 is a key molecule for thyroid morphogenesis and differentiation.This is the first large-scale study aimed at the identification of new genes regulated by Pax8, a master regulator of thyroid development and differentiation. The biological pathways and target genes controlled by Pax8 will have considerable importance to understand thyroid disease progression as well as to set up novel therapeutic strategies
Laser production of gas phase complexes of metal α-aminophosphonic acid mixtures and their role in chiral recognition
Clusters between first-group metal ions and chiralα-aminophosphonic acids have been readily generated by Pulsed Laser Ablation (PLA) and by Electrospray Ionization (ESI) and their fragmentation investigated by mass spectrometry. The complexes studied have the general formula[Me(I)Cl2]+, where Me(I) is H, Li, Na, or K, C is (R)-(—)-(1-aminoethyl) phosphonic acid(ER)and (S)-(+)-(1-aminoethyl) phosphonic acid(ES),(1R)-(+)-(1-amino-2-methylpropyl) phosphonic acid(PR)and (1S)-(—)-(1-amino-2-methylpropyl) phosphonic acid(PS),(1R)-(-)-(1-amino-hexyl) phosphonic acid (HR) and (1S)-(+)-(1-amino-hexyl) phosphonic acid (HS), o-phospho-L-serine (SS)ando-phospho-D-serine(SR), and L is a referenceα-aminophosphonic acid (E, P, H or S) of defined configuration. Collision induced dissociation (CID) of diastereomeric[Me(I)Cl2]+complexes leads to fragmentation patterns characterized by[Me(I)Cl]+/[Me(I)L2]+abundance ratios which depend upon the configuration of solute C. These different spectral features were correlated to the different stability of the diastereomeric[Me(I)CRL]+and[Me(I)CSL]+complexes in the gas phase
Review of the catch and catch-at-age estimation for the E-BFT catch inflated estimates 1998-2007
During the 2022 Eastern Atlantic and Mediterranean Bluefin Tuna Data Preparatory Meeting, the Bluefin Species Group (BFTSG) agreed to revise the assumptions and update the catch-atsize/catch-at-age (CAS/CAA) intersessionally by replacing the "NEI (inflated)" partial catches component (1998-2007) with a new set of combined Mediterranean size samples. An ad-hoc small group was formed to carry out this task and proposed an alternative CAS/CAA for the 2022 E-BFT stock assessment, this document summarizes these analyses. This document provides the revised CAS (version 2b), and two CAA based on the von Bertalanffy and the Richards growth
curves. The small group agreed that this revised CAS is a better estimate of the size distribution for the NEI-inflated catch and proposed to be adopted by the BFTSG, and aso recommended that this revision would be applied only to VPA (Virtual Population Analysis) and possibly ASAP (Age Structured Assessment Program)
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