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AbstractMolecular dynamics (MD) simulations were used to evaluate some chelating agents as potential candidates to inhibitors for dissimilatory adenosine-5’-phosphosulfate reductase (APSrAB). Molecular docking methods were used to evaluate the best binding modes of these molecules to the enzyme at two binding sites: of the substrate (enzyme active site) by mean the redocking protocol of substrate; and of one of the [Fe4S4]2+groups by mean of the clusterization protocol. The best docking poses were selected by criteria such as low energy and RMSD (redocking) and the cluster with the higher number of similar poses (clusterization), which were submitted to MD simulations. RMSD, RDF, and hydrogen bonds results revelated that all ligands left the cube site, while in the active site, some ligands remained in their docking region, pointing to the enzyme active site as the best target for the selected ligands. The binding energy results of ligands hydroxamic acid (HXA) and catechol (CAT) showed that they bonded favorably to the enzyme and key residues of the active site contributed significantly to the protein-ligand bind, indicating HAX and CAT may compete with the substrate for interactions with these residues and displaying potential as candidates for experimental studies about APSrAB inhibitors.Communicated by Ramaswamy H. Sarma

Rodrigues, GM, Machado, S, Faria Vieira, LA, Ramalho de Oliveira, BR, Jesus Abreu, MA, Marquez, G, Maranhão Neto, GA, and Lattari, E. Effects of anodal transcranial direct current stimulation on training volume and pleasure responses in the back squat exercise following a bench press. J Strength Cond Res36(11): 3048–3055, 2022—This study aimed to investigate the effects of anodal transcranial direct current stimulation (a-tDCS) on volume-load and pleasure responses in a back squat following a bench press. Twelve male subjects advanced in resistance training (RT) (age, 25.5 ± 4.4 years) completed 2 experimental trials in a counterbalanced crossover design: a-tDCS and sham conditions. The stimulus was applied over the left dorsolateral prefrontal cortex for 20 minutes using a 2-mA current intensity in a-tDCS condition and 1 minute of active stimulus in the sham condition. Immediately after stimulation, subjects performed the bench press followed by the back squat. The exercise protocol consisted of 3 sets of maximum repetitions at an intensity of 80% of 1 repetition maximum. The volume-load, perceived pleasure, and arousal responses were measured during the RT protocol. The results indicated that volume-load was higher in the a-tDCS condition than in the sham condition for both exercises (p= 0.02), with large effect for the back squat (p= 0.045; d= 0.96). The higher volume-load was obtained by increasing the number of repetitions across all sets for the bench press (p≤ 0.0001) and only in the first set for the back squat (p= 0.01). The circumplex model analysis showed a higher pleasure in the bench press and a tendency toward a higher pleasure in the a-tDCS condition. Anodal tDCS may be used as an ergogenic resource for increasing the back squat volume after performing the bench press in resistance-trained male subjects.

AbstractDFT calculations were used to obtain parameters compatible with the CHARMM36 force field for iron-sulfur clusters (Fe-S) of the type [Fe4S4]2+that are coordinated to dissimilatory adenosine-5’-phosphosulfate reductase (APSrAB). Classical molecular dynamics (MD) simulations were performed on two APSrAB systems to validate the parameters and verify the stability of the studied systems. The time analysis of the parameters inserted into the force field was in reasonable agreement with the experimental X-ray diffraction data. The analysis of the time evolution of the studied systems indicated that these systems and, in particular, the clusters in their respective cavities had a good stability and were in agreement with what was observed in previous works. The parameters obtained provide the basis for the study of APSrAB as well as other systems that contain [Fe4S4]2+through the CHARMM36 force field.

According to the World Health Organization (WHO), 47 million people display mental health disorders Worldwide. In addition, epidemiological studies have shown that the extension of life expectancy and the increase in aged population will significantly impact the prevalence of several mental impairments. Although there are strategies for preventing and alleviating mental illnesses, such as pharmacological and psychological approaches, limited results have been observed. Thus, the search for new therapeutics for managing psychiatric disorders has explored multiple roads. In recent years, it has been demonstrated that physical activity and exercise promote health benefits. On the other hand, among the neurobiological systems that participate in the genesis and development of mental disruptions, the endocannabinoid system has been suggested as an active player. Supporting this hypothesis, data suggest that the elements comprising the endocannabinoid system, such as the CB1/CB2 cannabinoid receptors, endogenous ligands (N-arachidonoylethanolamine [anandamide, AEA] and 2- arachidonoylglycerol [2-AG]), transporters and the enzymes involved in the biosynthesis and degradation of the AEA and 2-AG, modulate mental diseases. In this review, we discuss that the endocannabinoid system might be considered as a modulator for the positive outcomes of exercise in the management of mental disorders. Clinically, this promising field might be exploited by targeting the elements of the endocannabinoid system aimed to increase the exercise benefits applied to patients with mental illnesses.

The peroxisome proliferator activated receptors (PPARs) are a superfamily of well-recognized ligand-binding nuclear receptors comprising three isoforms: PPARα, PPARγ, and PPARβ/δ. In response to endogenous lipid messengers, PPARs trigger the transcription of genes related to a wider spectrum of physiological phenomena, including fatty acid oxidation, inflammation, adipogenesis, among many others. Thus, the importance of PPARs as putative protective therapy in health issues has increased the interest of studying these nuclear receptors, including the management of neurodegenerative disorders, multiple sclerosis, and likely addiction. In recent years, several pieces of evidence from animal models have demonstrated the promising role of PPARs as a critical element for interventions in addictive behaviors by reducing the reinforcing properties of addictive substances such as alcohol. However, there is a lack of data in the scope and has so far been unexplored the function of PPARs in additional drugs such as cannabis, opioids, methamphetamine, or cocaine. A similar scenario has been found for the management of binge-type eating disorders. Thus, here we review recent advances in understanding the relevance of the PPAR controlling addiction.

The intensity of resistance training (RT) exercise is an important consideration for determining relevant health and performance-related outcomes. Yet, current objective exercise intensity measures present concerns in terms of viability or cost. In response to these concerns, repetition-in-reserve (RIR) scales may represent an adequate method of measuring and regulating intensity. However, no recent review has focused on how RIR scales have been used for this purpose in prior research. We prepared the present scoping review to analyze the feasibility and usefulness of RIR scales in selecting RT intensity. We conducted a systematic search in PubMed, SPORTDiscus, PsycINFO, and ClinicalTrials.gov databases (last search date April 2023) for experimental and non-experimental studies that utilized an RIR scale to measure proximity to failure in RT activities with apparently healthy individuals of any age. We qualitatively analyzed 31 studies (N = 855 mostly male adult participants) published between 2012-2023. RIR scales appeared to be contextually feasible and useful in prescribing and adjusting RT intensity. The most common trend in this research was to prescribe a target RIR and adjust the exercise load for a desired proximity to muscle failure. Additionally, when measuring proximity to failure as an outcome of interest, the literature suggests that the RIR prediction should be made close to task failure to increase its accuracy. Future research should further explore the impact of sex, RT experience, exercise selection, and muscle conditioning on the overall RIR approach.

The ability of nitrogenated derivatives of furfural to act as corrosion inhibitors for mild steel in 1molL−1HCl solution was evaluated using weight-loss measurements, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). The imine 2-((furan-2-ylmethylene)amino)ethan-1-ol (1)and the mixture of 2-(furan-2-yl)-1,3-oxazinane and 3-((furan-2-ylmethylene)amino)propan-1-ol (2a+b)presented, respectively, 81.9% and 84.4% of inhibition efficiency towards the mild steel acidic corrosion at 5×10−3molL−1, room temperature and 2-h immersion time. Polarization curves showed more effective inhibition in the cathodic process. EIS plots indicated an increase in the polarization resistance with enhancement of inhibitor concentration. The adsorption of the evaluated inhibitors obeyed the Langmuir adsorption isotherm. The ΔG°adsand ΔH°adsvalues obtained suggest a physical nature adsorption of inhibitors (1)and (2a+b). The physisorption could be explained by the coulombic interaction between the protonated forms of the inhibitor molecules due to the acid medium with the negatively charged surface. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the surface morphologically and chemically, respectively. Quantum chemical calculations were applied to correlate electronic structure parameters of inhibitors with their corrosion inhibition efficiency.

Aging is an inevitable process that involves changes across life in multiple neurochemical, neuroanatomical, hormonal systems, and many others. In addition, these biological modifications lead to an increase in age-related sickness such as cardiovascular diseases, osteoporosis, neurodegenerative disorders, and sleep disturbances, among others that affect activities of daily life. Demographic projections have demonstrated that aging will increase its worldwide rate in the coming years. The research on chronic diseases of the elderly is important to gain insights into this growing global burden. Novel therapeutic approaches aimed for treatment of age-related pathologies have included the endocannabinoid system as an effective tool since this biological system shows beneficial effects in preclinical models. However, and despite these advances, little has been addressed in the arena of the endocannabinoid system as an option for treating sleep disorders in aging since experimental evidence suggests that some elements of the endocannabinoid system modulate the sleep-wake cycle. This article addresses this less-studied field, focusing on the likely perspective of the implication of the endocannabinoid system in the regulation of sleep problems reported in the aged. We conclude that beneficial effects regarding the putative efficacy of the endocannabinoid system as therapeutic tools in aging is either inconclusive or still missing.

This study describes a systematic investigation of the electrocatalytic activity of poly[Ni(salen)] films, as catalysts for the electro-oxidation of Cn alcohols (Cn = methanol, ethanol, and glycerol) in alkaline medium. The [Ni(salen)] complex was electropolymerized on a glassy carbon surface and electrochemically activated in NaOH solution by cyclic voltammetry. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy results indicate that during the activation step the polymeric film hydrolyzes, leading to the formation of β-Ni(OH)2spherical nanoparticles, with an average size of 2.4 ± 0.5 nm, encapsulated with the poly[Ni(salen)] film. Electrochemical results obtained together with the in situ Fourier transform infrared spectroscopy confirm that the electro-oxidation of methanol, ethanol, and glycerol occurs by involving a cycling oxidation of β-Ni(OH)2with the formation of β-NiOOH species, followed by the charge transfer to the alcohols, which regenerates β-Ni(OH)2. Analyses of the oxidation products at low potentials indicate that the major product obtained during the oxidation of methanol and glycerol is the formate, while the oxidation of ethanol leads to the formation of acetate. On the other hand, at high potentials (E= 0.6 V), there is evidence that the oxidation of Cn alcohols leads to carbonate ions as an important product.

Objective: Aging is a natural biological phenomenon that occurs in human beings. With increasing of age, there is an appearance of deleterious changes related to progression onto pathological conditions, including hypertension, heart disease, diabetes, hearing and vision impairments, as well as sleep disorders. It is important to recognize that some sleep disturbances reported by aged subjects include insomnia, obstructive sleep apnea, restless legs syndrome, among others. Moreover, accumulating evidence indicates that coexistence of medical issues with sleep disorders constitutes clinical challenges for treatment of comorbidities in elderly. Here, we have attempted to review and summarize the available literature that assesses the sleep disturbances in aging. In addition, we highlight the management of sleep disorders associated with aging. Due to the particular health condition of aged adults, the development of effective pharmacological interventions for sleep disorders treatment in aging is warranted. Methods: Review of studies retrieved from the PubMed. Results: The sleep-wake cycle includes abnormalities classified as sleep disorders. Comorbidity between sleep disturbances and aging-related health issues will represent a public health challenge to be addressed in the near future. Moreover, this scenario will suggest an area that requires further drug investigation and design of new pharmacological and pharmaceutical strategies to treat sleep disorders in the elderly population. Conclusion: The review highlights the sleep disturbances in aging. We focus on current knowledge in medicinal chemistry and further design of new treatments tools for managing sleep disturbances in the aged population.

This study aimed to analyze measurement invariance of the Behavioral Regulation Sports Questionnaire (BRSQ) across gender and four different sports. In addition, we examined nomological validity via basic psychological needs satisfaction. Participants totaled 1,812 Portuguese athletes (1,220 males and 592 females; aged 15–59 years, Mage = 17.72, SD= 5.51) from football (n= 596), basketball (n= 273), swimming (n= 800), and parasport (n= 143). The BRSQ measurement model was invariant across gender and these four sports. The scale confirmed nomological validity in that satisfaction of basic psychological needs positively predicted autonomous forms of motivation and negatively predicted more controlled motivation and amotivation as suggested by self-determination theory. In light of this evidence for BRSQ construct validity, composite reliability, nomological validity, and invariance across gender and four different sports, this scale is a useful tool for coaches of the aforementioned sports in their efforts to evaluate their athletes' motivation.

Background: Essential Tremor (ET) is a disease present in neurodegenerative disorders, such as Parkinson´s disease. Besides the motor dysfunction, ET also causes sleep problems, including excessive daytime sleepiness. To manage ET, several compounds are prescripted, such as primidone. However, no evidence is available regarding the effects of primidone on sleep. Objective: We analyzed the effects of systemic injections of primidone on sleep in rats. Method: Rats with sleep electrodes received different doses of primidone (0, 5, 10 or 50mg/Kg, i.p.) at the beginning of the lights-on period. Next, the effects of primidone on the states of vigilance were characterized. Results: At the highest dose of primidone (50mg/Kg), animals displayed an increase in Wakefulness (W) whereas Slow Wave Sleep (SWS) and Rapid Eye Movement Sleep (REMS) were decreased. In addition, sleep parameters such as the number of bouts, mean duration and latency were affected in primidone-treated animals. In this regard, the drug caused an enhancement in the number of bouts of W and SWS while the number of events of REMS showed a diminution. Regarding the mean duration, we found that SWS was decreased after primidone treatments whereas W and REMS remained with no statistical changes. Lastly, the latency of SWS was enhanced in primidone-treated animals while no statistical changes were found in REMS. Conclusion: Our findings demonstrate that primidone, a drug that is used to control ET, provokes wake-inducing effects in rats.