Absence Of EtOH Research Articles

Transport numbers of ion-exchange membranes in ternary mixtures of KCl, H2O and ethanol relevant for electrodialysis and desalination processes

Understanding the transport phenomena in electrolyte mixtures involved in electrochemical processes is of utmost importance for the modelling and improvement of battery technology, fuel cells, ion-exchange membrane processes, and much more. In this work, we derive relations and present methods for the analysis of electric potential measurements of concentration cells and ion-exchange membrane permselectivity with ternary mixtures of KCl, H2O and ethanol (EtOH). Measurements of electric potentials across the Selemion CMVN (cation-exchange) and AMVN (anion-exchange) membranes in this ternary mixture suggest that the presence of EtOH affects the membrane permselectivity, but that the transference of EtOH is zero; i.e., ta=0. Instead, the decrease in membrane permselectivity can be explained by a varying water transference coefficient, tw. In the absence of EtOH we find tw≈4 in both membranes, and that the decrease in tw is proportional to the average thermodynamic activity of EtOH in mixtures adjacent to the membranes. The membranes were also found to be charge selective, as quantified by the ionic transport numbers; i.e., tK+=1 for the Selemion CMVN and tK+=0 for the Selemion AMVN. The presented method can readily be extended and leveraged to determine transference coefficients in other electrochemical systems.

Co-pigmentation of Pinotage anthocyanins with Cyclopia (honeybush) polyphenols in model wine solutions

Co-pigmentation of an anthocyanin-enriched fraction (AEF) of Pinotage wine with honeybush polyphenols (Cyclopia subternata extract and fractions enriched in specific polyphenols) was studied in model wine solutions. The hyperchromic effects and bathochromic shifts depended on the co-pigment sources and co-pigment/anthocyanin ratio. Fraction 2 (F2), enriched in xanthones (mangiferin and isomangiferin), produced the most pronounced co-pigmentation effect at a co-pigment/anthocyanin ratio of 15:1. Greater co-pigmentation effects were observed in model solutions at pH 3.0 (pH 3–4 evaluated) and in the absence of EtOH (0–16 % EtOH evaluated). During storage of solutions (AEF and/or F2) at 15 °C and 25 °C for 12 weeks, myrtillin, petunin, 3′,5′-di-β-D-glucopyranosyl-3-hydroxyphloretin and mangiferin concentrations decreased following first-order kinetics, while peonin and oenin degradation followed fractional-conversion kinetics. Polymeric anthocyanin formation followed zero-order kinetics. Reaction rates increased with an increase in storage temperature. The addition of F2 to the AEF solution produced a darker, more vivid colour and improved the colour stability, however, the yellow-orange colour of F2 and intensification of its colour during storage contributed to increasing red-orange hues. Further research is necessary to elucidate the effect of honeybush polyphenols on the colour and composition of a complete wine as it is more complex than model solutions.

Inhibitory and excitatory alcohol-seeking cues distinct roles in behavior, neurochemistry, and mesolimbic pathway in alcohol preferring (P) rats

Cues associated with alcohol use can readily enhance self-reported cravings for alcohol, which increases the likelihood of reusing alcohol. Understanding the neuronal mechanisms involved in alcohol-seeking behavior is important for developing strategies to treat alcohol use disorder. In all experiments, adult female alcohol-preferring (P) rats were exposed to three conditioned odor cues; CS+ associated with EtOH self-administration, CS- associated with the absence of EtOH (extinction training), and a CS0, a neutral stimulus. The data indicated that presentation of an excitatory conditioned cue (CS+) can enhance EtOH- seeking while the CS- can inhibit EtOH-seeking under multiple test conditions. Presentation of the CS+ activates a subpopulation of dopamine neurons within the interfascicular nucleus of the posterior ventral tegmental area (posterior VTA) and basolateral amygdala (BLA). Pharmacological inactivation of the BLA with GABA agonists inhibits the ability of the CS+ to enhance EtOH-seeking but does not alter context-induced EtOH-seeking or the ability of the CS- to inhibit EtOH-seeking. Presentation of the conditioned odor cues in a non-drug-paired environment indicated that presentation of the CS+ increased dopamine levels in the BLA. In contrast, presentation of the CS- decreased both glutamate and dopamine levels in the BLA. Further analysis revealed that presentation of a CS+ EtOH-associated conditioned cue activates GABA interneurons but not glutamate projection neurons. Overall, the data indicate that excitatory and inhibitory conditioned cues can contrarily alter EtOH-seeking behaviors and that different neurocircuitries are mediating these distinct cues in critical brain regions. Pharmacotherapeutics for craving should inhibit the CS+ and enhance the CS- neurocircuits.

Gravity sedimentation of eukaryotic algae Euglena gracilis accelerated by ethanol cultivation.

Euglena gracilis (E. gracilis) is a unicellular microalga with various applications in medicine, agriculture, aquaculture, health supplement, and jet fuel production. Euglena possibly solves population growth and exhaustion of fossil resources. Efficient cell harvesting is needed for the industry, and the gravity sedimentation method is low cost and does not require any equipment, although it has low efficiency. This study showed that the gravity sedimentation of E. gracilis cells is improved by cultivation in the presence of ethanol (EtOH). The gravity sedimentation of E. gracilis cells cultivated under 0.5% or 1.0% EtOH conditions was faster than that cultivated without EtOH. The mean calculated cell diameter was also found to be largest in cells cultivated under 0.5% or 1.0% EtOH conditions compared to that in cells cultivated without EtOH. Intracellular paramylon content, cell shapes, and motility differed between cells cultivated under 0.5% or 1.0% EtOH conditions and in the absence of EtOH. The results suggest that E. gracilis cultivation with EtOH leads to increased cell productivity, paramylon production, and efficient cell harvesting. KEY POINTS: • Euglena gracilis is an edible microalga producing value-added metabolites. • Ethanol addition upregulates E. gracilis growth and paramylon accumulation. • Gravity sedimentation is accelerated by ethanol-grown E. gracilis cells.

Normalization of the EOR catalytic efficiency measurements based on RRDE study for simply fabricated cost-effective Co/graphite electrode for DAEFCs

• Facile fabrication of low-cost and highly efficient Co/graphite electrocatalyst for direct alkaline ethanol fuel cells (DAEFC). • RRDE study for effective distinction between EOR and OER processes. • Normalized parameters for reliable measuring EOR catalytic efficiency. For the catalytic oxidation of ethanol (EtOH), Co is chronoamperometricaly deposited on graphite (G) from 0.05 M CoCl 2 solution with an optimum potential of −1.1 V for 1000 s. The optimum produced Co/G (opt.) electrode yields an ethanol oxidation onset potential (Et-E onset ) 1.43 V/RHE and a current density, I at 1.6 V/RHE = 26.58 mA.cm −2 at a scan rate of 50 mV.s -1 . Its cyclic voltammetry (CV) and rotating ring-disc (RRDE) responses, in solutions of 0.5 M NaOH without and with 1 M EtOH, show the priority of ethanol oxidation reaction (EOR) rather than the oxygen evolution reaction (OER) or transformation of CoOOH to CoO 2 in the potential range 1.4 ≤ E ≤ 1.8 V/RHE. The RRDE responses are used to distinguish between EOR and OER currents in presence of ethanol. The present study includes sincere efforts to resolve the controversy about the measurement of the ethanol oxidation activity parameters. In addition, Co/G (opt.) electrode shows remarkable activity and stability for OER in absence of EtOH. Its overpotential required to achieve 10 mA.cm −2 ( η t = 0 ) is 0.38 V; while, after 24 h, (η t=24h ) is 0.40 V. These values are a noteworthy outcome for our easy and straightforward fabrication method for such an efficient EOR/OER electrocatalyst expending low-cost materials when compared with the previously published work.

Computational and Experimental Evaluation of the Stability of a GLP-1-like Peptide in Ethanol-Water Mixtures.

Aggregation resulting from the self-association of peptide molecules remains a major challenge during preformulation. Whereas certain organic solvents are known to promote aggregation, ethanol (EtOH) is capable of disrupting interactions between peptide molecules. It is unclear whether it is beneficial or counterproductive to include EtOH in formulations of short peptides. Here, we employed molecular dynamics simulations using the DAFT protocol and MARTINI force field to predict the formation of self-associated dimers and to estimate the stability of a GLP-1-like peptide (G48) in 0–80% aqueous EtOH solutions. Both simulation and experimental data reveal that EtOH leads to a remarkable increase in the conformational stability of the peptide when stored over 15 days at 27 °C. In the absence of EtOH, dimerisation and subsequent loss in conformational stability (α-helix → random coil) were observed. EtOH improved conformational stability by reducing peptide–peptide interactions. The data suggest that a more nuanced approach may be applied in formulation decision making and, if the native state of the peptide is an α-helix organic solvent, such as EtOH, may enhance stability and improve prospects of long-term storage.

Intestinal Epithelial Cell-Derived Extracellular Vesicles Modulate Hepatic Injury via the Gut-Liver Axis During Acute Alcohol Injury.

Binge drinking, i.e., heavy episodic drinking in a short time, has recently become an alarming societal problem with negative health impact. However, the harmful effects of acute alcohol injury in the gut-liver axis remain elusive. Hence, we focused on the physiological and pathological changes and the underlying mechanisms of experimental binge drinking in the context of the gut-liver axis. Eight-week-old mice with a C57BL/6 background received a single dose (p.o.) of ethanol (EtOH) [6 g/kg b.w.] as a preclinical model of acute alcohol injury. Controls received a single dose of PBS. Mice were sacrificed 8 h later. In parallel, HepaRGs and Caco-2 cells, human cell lines of differentiated hepatocytes and intestinal epithelial cells intestinal epithelial cells (IECs), respectively, were challenged in the presence or absence of EtOH [0–100 mM]. Extracellular vesicles (EVs) isolated by ultracentrifugation from culture media of IECs were added to hepatocyte cell cultures. Increased intestinal permeability, loss of zonula occludens-1 (ZO-1) and MUCIN-2 expression, and alterations in microbiota—increased Lactobacillus and decreased Lachnospiraceae species—were found in the large intestine of mice exposed to EtOH. Increased TUNEL-positive cells, infiltration of CD11b-positive immune cells, pro-inflammatory cytokines (e.g., tlr4, tnf, il1β), and markers of lipid accumulation (Oil Red O, srbep1) were evident in livers of mice exposed to EtOH, particularly in females. In vitro experiments indicated that EVs released by IECs in response to ethanol exerted a deleterious effect on hepatocyte viability and lipid accumulation. Overall, our data identified a novel mechanism responsible for driving hepatic injury in the gut-liver axis, opening novel avenues for therapy.

Evaluation of self-emulsifying drug delivery systems for oral insulin delivery using an in vitro model simulating the intestinal proteolysis

The gentle preparation and the functionalization potential of self-emulsifying drug delivery systems (SEDDS) make them an interesting formulation strategy for oral administration of peptide and protein (p/p) drugs.A series of Kolliphor® RH40 (RH40) and Labrasol® (LAB)-based SEDDS containing either long-chain (LC) or medium-chain (MC) glycerides were formulated and characterized with regard to their rheological behavior, as well as the size distribution and zeta potential of the generated emulsions. Insulin, in order to be incorporated in SEDDS, was complexed with soybean phosphatidylcholine. The ability of different SEDDS to protect the incorporated insulin against enzymatic hydrolysis was evaluated by an in vitro model simulating the intestinal proteolysis. SEDDS were incubated in simulated intestinal fluids in the presence of α-Chymotrypsin (α-CT), and HPLC was used to quantify the remaining insulin. Principal component analysis (PCA) was applied to identify the relations between different excipients and properties of SEDDS that describe the SEDDS protective effect on insulin during in vitro proteolysis.The RH40-SEDDS behaved Newtonian in the presence of ethanol (EtOH) and non-Newtonian in the absence of EtOH, which generated emulsion with droplets between 30 to 300 nm. The LAB-SEDDS always behaved Newtonian and generated polydisperse emulsions with broad size distribution (190–4000 nm). During the in vitro proteolysis, insulin can be effectively protected against α-CT (> 60% remaining insulin after 60 min in vitro proteolysis). According to PCA analysis, insulin was better protected in MC-SEDDS compared to LC-SEDDS, and better in LAB-SEDDS compared to RH40-SEDDS. Monoacyl phosphatidylcholine and Capmul® MCM C8 were recognized as excipients favored for SEDDS protection on insulin. However, SEDDS viscosity and the addition of EtOH in SEDDS played insignificant roles on the remaining insulin after in vitro proteolysis.In summary, an in vitro proteolysis model with increased physiological relevance was applied to enable the optimal design of SEDDS for oral p/p drug delivery.

Conditioned stimuli affect ethanol-seeking by female alcohol-preferring (P) rats: the role of repeated-deprivations, cue-pretreatment, and cue-temporal intervals.

Evidence indicates that drug-paired stimuli can evoke drug-craving leading to drug-seeking and repeated relapse periods can influence drug-seeking behaviors. The present study examined (1) the effect of an interaction between repeated deprivation cycles and excitatory conditioning stimuli (CS+) on ethanol (EtOH)-seeking; (2) the effects of EtOH-paired cue-exposure in a non-drug-paired environment on subsequent conditioning in a drug-paired environment; and (3) the temporal effects of conditioned cues on subsequent EtOH-seeking. Adult female alcohol-preferring (P) rats were exposed to three conditioned odor cues; CS+ associated with EtOH self-administration, CS- associated with the absence of EtOH (extinction training), and a neutral stimulus (CS0) presented in a neutral non-drug-paired environment. The rats underwent four deprivation cycles or were non-deprived, following extinction they were maintained in a home cage for an EtOH-free period, and then exposed to no cue, CS+, CS-, or CS0 to assess the effect of the conditioned cues on EtOH-seeking behavior. Repeated deprivations enhanced and prolonged the duration of CS+ effects on EtOH-seeking. Presentation of the CS- in a non-drug-paired environment blocked the ability of a CS+ to enhance EtOH-seeking in a drug-paired environment. Presentation of the CS+ or CS- in a non-drug-paired environment 2 or 4h earlier significantly altered EtOH-seeking. Results indicated an interaction between repeated deprivation cycles and CS+ resulted in a potentiation of CS+ evoked EtOH-seeking. In addition, a CS- may have therapeutic potential by providing prophylactic protection against relapse behavior in the presence of cues in the drug-using environment.

Parameters of Context-Induced Ethanol (EtOH)-Seeking in Alcohol-Preferring (P) Rats: Temporal Analysis, Effects of Repeated Deprivation, and EtOH Priming Injections.

Drug-paired environments can act as stimuli that elicit drug craving. In humans, drug craving is influenced by the amount of time abstinent, number of past periods of abstinence, and inadvertent exposure to the previously abused drug. The current experiments were designed to determine the effects of (i) the duration of abstinence on expression of ethanol (EtOH)-seeking; (ii) EtOH priming following a short and long abstinence period; and (iii) repeated deprivation cycles on relapse drinking and EtOH-seeking. Rats were allowed to self-administer 15% EtOH, processed through extinction training, maintained in a home cage for a designated EtOH-free period, and then reintroduced to the operant context in the absence of EtOH. The experiments examined the effects of: (i) various home-cage duration periods (1 to 8weeks), (ii) priming injections of EtOH in the Pavlovian spontaneous recovery (PSR; 14days after extinction) and reinstatement of responding (RoR; 1 day after extinction) models, and (iii) exposure to repeated cycles of EtOH access-deprivation on relapse drinking and EtOH-seeking behavior. Highest expression of EtOH-seeking was observed following 6weeks of home-cage maintenance. Priming injections of EtOH were more efficacious at stimulating/enhancing EtOH-seeking in the PSR than RoR model. Exposure to repeated cycles of EtOH deprivation and access enhanced and prolonged relapse drinking and the expression of EtOH-seeking (318±22 responses), which was not observed in rats given equivalent consistent exposure to EtOH (66±11 responses). Overall, the data indicated that the PSR model has ecological validity; factors that enhance EtOH craving in humans enhance the expression of EtOH-seeking in the PSR test. The data also detail factors that need to be examined to determine the biological basis of EtOH-seeking (e.g., neuroadaptations that occur during the incubation period and following repeated cycles of EtOH drinking and abstinence).

PCDHB14- and GABRB1-like nervous system developmental genes are altered during early neuronal differentiation of NCCIT cells treated with ethanol.

Ethanol (EtOH) exposure during embryonic development causes dysfunction of the central nervous system (CNS). Here, we examined the effects of chronic EtOH on gene expression during early stages of neuronal differentiation. Human embryonic carcinoma (NCCIT) cells were differentiated into neuronal precursors/lineages in the presence or absence of EtOH and folic acid. Gene expression profiling and pathway analysis demonstrated that EtOH deregulates many genes and pathways that are involved in early brain development. EtOH exposure downregulated several important genes, such as PCDHB14, GABRB1, CTNND2, NAV3, RALDH1, and OPN5, which are involved in CNS development, synapse assembly, synaptic transmission, and neurotransmitter receptor activity. GeneGo pathway analysis revealed that the deregulated genes mapped to disease pathways that were relevant to fetal alcohol spectrum disorders (FASD, such as neurotic disorders, epilepsy, and alcohol-related disorders). In conclusion, these findings suggest that the impairment of the neurological system or suboptimal synapse formation resulting from EtOH exposure could underlie the neurodevelopmental disorders in individuals with FASD.

Choline partially prevents the impact of ethanol on the lipid raft dependent functions of l1 cell adhesion molecule.

Fetal alcohol spectrum disorder, the leading known cause of mental retardation, is caused by alcohol exposure during pregnancy. One mechanism of ethanol (EtOH) teratogenicity is the disruption of the functions of L1 cell adhesion molecule (L1). These functions include enhancement of neurite outgrowth, trafficking through lipid rafts, and signal transduction. Recent data have shown that choline supplementation of rat pups reduces the effects of EtOH on neurobehavior. We sought to determine whether choline could prevent the effect of EtOH on L1 function using a simple experimental system. Cerebellar granule neurons (CGN) from postnatal day 6 rat pups were cultured with and without supplemental choline, and the effects on L1 signaling, lipid raft distribution, and neurite outgrowth were measured in the presence or absence of EtOH. Choline significantly reduced the effect of EtOH on L1 signaling, the distribution of L1 in lipid rafts and L1-mediated neurite outgrowth. However, choline supplemented EtOH-exposed cultures remained significantly different than controls. Choline pretreatment of CGN significantly reduces the disruption of L1 function by EtOH, but does not completely return L1 function to baseline. This experimental system will enable discovery of the mechanism of the neuroprotective effect of choline.

Postnatal Ethanol Exposure Simplifies the Dendritic Morphology of Medium Spiny Neurons Independently of Adenylyl Cyclase 1 and 8 Activity in Mice

Fetal exposure to alcohol can have multiple deleterious effects, including learning disorders and behavioral and executive functioning abnormalities, collectively termed fetal alcohol spectrum disorders. Neonatal mice lacking both calcium-/calmodulin-stimulated adenylyl cyclases (ACs) 1 and 8 demonstrate increased vulnerability to ethanol (EtOH)-induced neurotoxicity in the striatum compared with wild-type (WT) controls. However, the developmental impact on surviving neurons is still unclear. WT and AC1/8 double knockout (DKO) mice were administered 1 dose of EtOH (2.5 g/kg) between postnatal days 5 to 7 (P5-7). At P30, brains were removed and processed for Golgi-Cox staining. Medium spiny neurons (MSNs) from the caudate putamen were analyzed for changes in dendritic complexity; number of branches, branch points and terminals, total and average dendritic length; spine density and soma size. EtOH significantly reduced the dendritic complexity and soma size in surviving MSNs regardless of genotype without affecting spine density. In the absence of EtOH, genetic deletion of AC1/8 reduced the dendritic complexity, number of branch points, spine density, and soma size of MSNs compared with WT controls. These data indicate that neonatal exposure to a single dose of EtOH is sufficient to cause long-term alterations in the dendritic complexity of MSNs and that this outcome is not altered by the functional status of AC1 and AC8. Therefore, although deletion of AC1/8 demonstrates a role for the ACs in normal morphologic development and EtOH-induced neurodegeneration, loss of AC1/8 activity does not exacerbate the effects of EtOH on dendritic morphology or spine density.

Activation of AMPK/TSC2/PLD by Alcohol Regulates mTORC1 and mTORC2 Assembly in C2C12 Myocytes

Ethanol (EtOH) decreases muscle protein synthesis, and this is associated with reduced mammalian target of rapamycin complex (mTORC)1 and increased mTORC2 activities. In contrast, phospholipase D (PLD) and its metabolite phosphatidic acid (PA) positively regulate mTORC1 signaling, whereas their role in mTORC2 function is less well defined. Herein, we examine the role that PLD and PA play in EtOH-mediated mTOR signaling. C2C12 myoblasts were incubated with EtOH for 18 to 24hours. For PA experiments, cells were pretreated with the drug for 25minutes followed by 50-minute incubation with PA in the presence or absence of EtOH. The phosphorylation state of various proteins was assessed by immunoblotting. Protein-protein interactions were determined by immunoprecipitation and immunoblotting. PLD activity was measured using the Amplex Red PLD assay kit. PA concentrations were determined with a total PA assay kit. PA levels and PLD activity increased in C2C12 myocytes exposed to EtOH (100mM). Increased PLD activity was blocked by inhibitors of AMP-activated protein kinase (AMPK) (compound C) and phosphoinositide 3-kinase (PI3K) (wortmannin). Likewise, suppression of PLD activity with CAY10594 prevented EtOH-induced Akt (S473) phosphorylation. PLD inhibition also enhanced the binding of Rictor to mSin1 and the negative regulatory proteins Deptor and 14-3-3. Addition of PA to myocytes decreased Akt phosphorylation, but changes in mTORC2 activity were not associated with altered binding of complex members and 14-3-3. PA increased S6K1 phosphorylation, with the associated increase in mTORC1 activity being regulated by reduced phosphorylation of AMPKα (T172) and its target tuberous sclerosis protein complex (TSC)2 (S1387). This resulted in increased Rheb and RagA/RagC GTPase interactions with mTOR, as well as suppression of mTORC2. EtOH-induced increases in PLD activity and PA may partially counterbalance the adverse effects of this agent. EtOH and PA regulate mTORC1 via a PI3K/AMPK/TSC2/PLD signaling cascade. PA stimulates mTORC1 function and suppresses activation of mTORC2 as part of an mTORC1/2 feedback loop.

CRF1 Receptor Signaling Regulates Food and Fluid Intake in the Drinking-in-the-Dark Model of Binge Alcohol Consumption

Several recent studies implementing the standard "drinking-in-the-dark" (DID) model of short-term binge-like ethanol (EtOH) intake in C57BL/6J mice highlighted a role for the stress-related neuropeptide corticotropin-releasing factor (CRF) and its primary binding partner, the CRF type-1 (CRF1) receptor. We evaluated the selectivity of CRF1 involvement in binge-like EtOH intake by interrupting CRF1 function via pharmacological and genetic methods in a slightly modified 2-bottle choice DID model that allowed calculation of an EtOH preference ratio. In addition to determining EtOH intake and preference, we also measured consumption of food and H2 O during the DID period, both in the presence and absence of EtOH and sweet tastant solutions. Treatment with either of the CRF1-selective antagonists CP-376,395 (CP; 10 to 20 mg/kg, i.p.) or NBI-27914 (10 to 30 mg/kg, i.p.) decreased intake of 15% EtOH in male C57BL/6J mice, but did so in the absence of a concomitant decrease in EtOH preference. These findings were replicated genetically in a CRF1 knockout (KO) mouse model (also on a C57BL/6J background). In contrast to effects on EtOH intake, pharmacological blockade of CRF1 with CP increased intake of 10% sucrose, consistent with previous findings in CRF1 KO mice. Finally, pharmacological and genetic disruption of CRF1 activity significantly reduced feeding and/or total caloric intake in all experiments, confirming the existence of nonspecific effects. Our findings indicate that blockade of CRF1 receptors does not exert specific effects on EtOH intake in the DID paradigm, and that slight modifications to this procedure, as well as additional consummatory control experiments, may be useful when evaluating the selectivity of pharmacological and genetic manipulations on binge-like EtOH intake.

Acute Ethanol Administration and Reinforcer Magnitude Reduction Both Reduce Responding and Increase Response Latency in a Go/No‐Go Task

Ethanol (EtOH) administration decreases behavioral inhibition in human subjects, assessed using cued Go/No-Go tasks, in which an unreliable cue suggests whether participants will be required to respond or not when a signal occurs. Few studies have examined EtOH's effects on behavioral inhibition in animals, and those that have done so have used Go/No-Go tasks in which no warning cue was provided. Two cohorts of male Long-Evans rats were trained and tested on 2 different Go/No-Go procedures with differing ratios of Go to No-Go trials (25 to 75 and 50 to 50). Using a within-subjects design, each rat was administered 0.0, 0.63, 0.95, and 1.27g/kg of EtOH (i.p.) on 3 separate occasions according to an incomplete Latin square. An additional experiment examined the effects of reducing the amount of sucrose given for correct responses to either the Go or the No-Go signal in the absence of EtOH administration. Acute intraperitoneal EtOH administration dose-dependently decreased responding during the No-Go signal (false alarms), the Go signal (hits), and responding prior to the occurrence of either signal (precue response rate). These effects were more pronounced in rats with the 50 to 50 ratio. Reducing the amount of sucrose presented generally led to a decrease in responding, although this effect was also moderated by the Go to No-Go ratio employed and the contingency relationship (reduced sucrose for correct Go trial responding or for correct No-Go trial response withholding). Acute EtOH administration does not decrease behavioral inhibition in rats in this task. Rather EtOH appears to dose-dependently decrease behavior in general, possibly by reducing the efficacy of the sucrose reinforcer, as both EtOH administration and sucrose reduction for Go trials yielded similar patterns of behavioral responding in this task in rats.

Ultradeep Adsorption−Desulfurization of Gasoline with Ni/Al−SiO2 Material Catalytically Facilitated by Ethanol

Adsorptive desulfurization of low-sulfur (22 ppmw) gasoline on solids in a liquid-full (no hydrogen) fixed bed was conducted at 503 K. Addition of 3 wt % ethanol to gasoline increased significantly the adsorption rate of sulfur-containing hydrocarbons on Ni/Al−SiO2 and its sulfur capacity, leading to <0.5 ppmw residual sulfur with a sulfur capacity of 2 wt % (mass of sulfur per mass of sorbent). Three potential routes for improving desulfurization performance of Ni sorbent in the presence of ethanol and its decomposition products containing CO and hydrogen were considered: (i) formation of nickel carbide (Ni3C) phase with reactivity toward S-organic compounds higher than that of metallic nickel, (ii) reduction of carbon deposits in the presence of hydrogen, and (iii) formation of nickel sulfide nanoparticles in the presence of H2/H2S vs adsorbed sulfur/sulfur organics that block the surface of metallic nickel in the absence of EtOH (hydrogen). Catalyst characterization data (N2 adsorption, XRD, EDX, HRTEM...

Solvation-assisted Pressure Tuning of Insulin Fibrillation: From Novel Aggregation Pathways to Biotechnological Applications

Solvation-assisted pressure tuning has been employed to unravel unknown structural and kinetic aspects of the insulin aggregation and fibrillation process. Our approach, using fluorescence, Fourier transform infrared and atomic force microscopy techniques in combination with pressure and solvent perturbation, reveals new insights into the pre-aggregated regime as well as mechanistic details about two concurrent aggregation pathways and the differential stability of insulin aggregates. Pressure uniformly fosters the dissociation of native insulin oligomers, whereas the aggregation pathways at elevated temperatures are affected by pressure differently and in a cosolvent-dependent manner. Moderate pressures accelerate the amyloid pathway in the presence of EtOH (leading to essentially monomeric aggregating species) via relatively dehydrated transition states with negative activation volumes for nucleation and elongation. Alternatively, a novel, fast equilibrium pathway to distinct beta-sheet-rich oligomers with thioflavin T-binding capability is accessible to partially unfolded insulin monomers at pressures below approximately 200 bar in the absence of EtOH. These oligomers, probably off the normal fibrillation pathway, are stabilized mainly by electrostatic and hydrophobic interactions, lacking the precise packing of mature insulin fibrils, which renders them susceptible to quantitative pressure-induced dissociation. Due to a highly negative activation volume for dissociation (-70(+/-16)ml/mol), pressure dissociation is fast and technologically feasible at ambient temperatures and moderate pressures. Becoming kinetically very labile above 35 degrees C, the pressurized oligomers can re-enter the slower, ultimately irreversible, fibrillation pathway at higher temperatures. At pressures above approximately 1000 bar, the partial unfolding of insulin monomers, accompanied by a volumetric expansion, dominates the aggregation kinetics, which manifests in a progressive inhibition of the fibrillation. Unlike their precursors, the pressure-insensitivity of mature insulin fibrils demonstrates that an extensive hydrogen bonding network and optimized side-chain packing are crucial for their stability.

Mitochondrially targeted vitamin E and vitamin E mitigate ethanol-mediated effects on cerebellar granule cell antioxidant defense systems

Ethanol (EtOH) disrupts the structure and function of the developing nervous system, sometimes leading to birth defects associated with fetal alcohol syndrome (FAS). Animal FAS models indicate that cellular membrane peroxidation, intracellular oxidant accumulation, and suppression of endogenous antioxidant enzymes contribute to the toxic effects of EtOH. Mitochondrially targeted vitamin E (MitoVit E), a chemically engineered form of vitamin E (VE) designed to accumulate in the mitochondria, has been shown to inhibit intracellular oxidant accumulation and cell death more effectively than VE. In previous investigations, we have shown that, in vivo, VE reduces neuronal death in the developing cerebellum of EtOH-exposed animals, and, in vitro, VE prevents apoptotic and necrotic death of EtOH-exposed cerebellar granule cells (CGCs). The present investigation shows that, in a FAS CGC model, 1 nM MitoVit E renders significant neuroprotection against EtOH concentrations as high as 1600 mg/dL. The present study also demonstrates that, in this same model, MitoVit E mitigates EtOH-induced accumulation of intracellular oxidants and counteracts suppression of glutathione peroxidase/glutathione reductase (GSH-Px/GSSG-R) functions, protein expression of gamma-glutamylcysteine synthetase (γ-GCS), and total cellular glutathione (GSH) levels. In the presence and absence of EtOH, VE amplifies the protein expression levels of γ-GCS, an enzyme that performs the rate-limiting step for GSH synthesis, and total GSH levels. These results suggest that MitoVit E and VE ameliorate EtOH toxicity through non-oxidant mechanisms–modulations of endogenous cellular proteins–and antioxidant means.

Inhibition of PAR4 Signaling in Ethanol-Attenuation of Platelet Function.

Background: Moderate consumption of alcohol beverages reduces the morbidity from coronary heart disease. Previous studies describing of inhibitory activity of ethanol (EtOH) on platelet function have substantiated this observation. However, the effects of EtOH on thrombin-related platelet activation remains to be fully elucidated, though platelet activation by thrombin is essential for normal hemostasis as well as relevant to pathophysiological conditions of thrombosis.Objectives: The aim of this study is to elucidate the effect of EtOH on α-thrombin-related platelet function by measuring platelet aggregation and intracellular calcium ([Ca2+]i).Materials and Methods: A dual-wavelength spectrofluorometer was used for measurement. α-thrombin, PAR1-activating peptide (AP) (10 μM) or PAR4-AP (25 μM) was added to fura2-AM loaded washed platelet preincubated with or without EtOH (40, 80, 160 and 320 mM).Results and Interpretations: First, the effects of EtOH on 0.5 nM of thrombin-induced platelet activation was assessed. The concentration 0.5 nM used is conceived to activate platelets only via PAR-1. EtOH did not affect platelet aggregation. EtOH inhibited rise of [Ca2+]i dose-dependently. [Ca2+]i peak time at which maximal rise of [Ca2+]i delayed in a dose-dependent manner.Secondly, 10 nM of thrombin was used as an agonist. Stimulation by high concentrations of thrombin (〉 5nM) results in cleavage of both PAR1 and PAR4. The changes in [Ca2+]i showed double-phase curve composed of transient spike and prolonged peak in the absence of EtOH. Although EtOH inhibited neither platelet aggregation nor the first phase of [Ca2+]i increasing, it reduced the second prolonged elevation of [Ca2+]i dose-dependently.To elucidate the inhibiting mechanism of EtOH more precisely, the effects of EtOH on PAR1-AP-induced platelet function were examined. Rise of [Ca2+]i gave a spike form and was almost unchanged even in the presence of high concentrations of EtOH, whereas platelet aggregation was reduced and dissociated in the presence of EtOH. Lastly, the effects of EtOH on PAR4-AP-induced platelet function was examined. Aggregation of PRP was quenched by high concentrations of EtOH but dissociation was not observed contrary to that observed in PAR1-AP-induced aggregation. Further, EtOH inhibited [Ca2+]i rise and delayed [Ca2+]i peak time dose-dependently.Our results provided a possible mechanism by which EtOH inhibits platelet activation. Reduction of the prolonged elevation of [Ca2+]i by high concentrations of thrombin suggested that EtOH inhibits PAR4 signaling not PAR1 since the second prolonged phase of [Ca2+]i is mediated by PAR4. Inhibition of PAR4-induced aggregation and [Ca2+]i elevation by EtOH supported the findings and EtOH might reduce Ca2+ influx through inhibition of PAR4.Furethermore, the difference between the platelet activation mechanisms of low concentrations of thrombin and PAR1-AP was suggested. PAR1-AP can aggregate platelets at least but might fail to activate phospholipase A2 required for sustaining stable aggregation since EtOH abolishes phospholipase A2 and thereby reduces thromboxane A2 generation. On the other, thrombin at low concentrations might have another pathway for activating platelet differently than PAR1-AP.Further characterization of the mechanisms involved in inhibition of platelet activation by EtOH may help develop new strategies to control thrombin-mediated platelet activation.