Quantum Effects Explain the Twist Angle in the Helical Structure of DNA.

Why are DNA bases stacked in a double helix structure? We combined three theoretical approaches to demonstrate how one core concept derived from quantum mechanics (Pauli repulsion) annihilates the contribution of dispersion to the π-π stacking. The helical architecture is governed by a combination of exchange and electrostatic forces, a result that is interpreted from both a computational and a biological perspective.

Effect of Levetiracetam on Oxidant-Antioxidant Activity during Long-Term Temporal Lobe Epilepsy in Rats.

Epilepsy is a disorder characterized by a predisposition to generate seizures. Levetiracetam (LEV) is an antiseizure drug that has demonstrated oxidant-antioxidant effects during the early stages of epilepsy in several animal models. However, the effect of LEV on oxidant-antioxidant activity during long-term epilepsy has not been studied. Therefore, the objective of the present study was to determine the effects of LEV on the concentrations of five antioxidant enzymes and on the levels of four oxidant stress markers in the hippocampus of rats with temporal lobe epilepsy at 5.7 months after status epilepticus (SE). The results revealed that superoxide dismutase (SOD) activity was significantly greater in the epileptic group (EPI) than in the control (CTRL), CTRL + LEV and EPI + LEV groups. No significant differences were found among the groups' oxidant markers. However, the ratios of SOD/hydrogen peroxide (H2O2), SOD/glutathione peroxidase (GPx) and SOD/GPx + catalase (CAT) were greater in the EPI group than in the CTRL and EPI + LEV groups. Additionally, there was a positive correlation between SOD activity and GPx activity in the EPI + LEV group. LEV-mediated modulation of the antioxidant system appears to be time dependent; at 5.7 months after SE, the role of LEV may be as a stabilizer of the redox state.

Introducing electron correlation in solid-state calculations for superconducting states.

Analyzing the electronic localization of superconductors has been recently shown to be relevant for understanding their critical temperature [Nature Communications, 12, 5381, (2021)]. However, these relationships have only been shown at the Kohn-Sham density functional theory (DFT) level, where the onset of strong correlation linked to the superconducting state is missing. In this contribution, we approximate the superconducting gap in order to reconstruct the superconducting the one-reduced density matrix (1RDM) from a DFT calculation. This allows us to analyse the electron density and localization in the strong correlation regime. The method is applied to two well-known superconductors. Electron localization features along the electron-phonon coupling directions and hydrogen cluster formations are observed for different solids. However, in both cases we see that the overall localization channels are not affected by the onset of superconductivity, explaining the ability of DFT localization channels to characterize the superconducting ones.

A 6-month educational program improves sleep behaviour in community-dwelling frail older adults: A randomised controlled trial.

BACKGROUND: The prevalence of sleep-related issues among older adults is a significant concern, with half of the older population reporting these problems. Consequently, strategies to improve sleep are needed for this population. This study aims to assess the effects of a health educational program on sleep behaviour among pre-frail or frail older adults residing in the community and to explore possible associations with frailty. METHODS: This randomised controlled trial (NCT05610605) included a total of 197 community-dwelling older adults with frailty/pre-frailty, divided into control (n = 88) and educational (n = 109) groups, were assessed at baseline, after the 6-month educational program (6 months), and 6 months after the intervention (12 months). The intervention comprised four group sessions and six follow-up phone calls, focusing on frailty, physical activity, dietary habits, and cognitive training. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and wrist-worn accelerometry. RESULTS: At 6 months, a significant time-by-group interaction was found for self-reported [ß = -0.449, 95%CI (-0.844, -0.053), p = 0.026] and accelerometer-measured [ß = 0.505, 95%CI (0.085, 0.926), p = 0.019] sleep efficiency, showing improved sleep efficiency in the intervention group vs. controls. A significant time-by-group interaction at 6 months was noted for sleep awakenings [ß = -0.402, 95%CI (-0.825, -0.020), p = 0.047]. The educational program led to a significant decrease in awakenings, while the control group experienced an increase. The change in the number of awakenings (Rs = 0.183, p = 0.020) at 6 months was significantly associated with changes in frailty. Moreover, a significant time-by-group interaction was reported at the 12-month assessment [ß = -0.449, 95%CI (-0.844, -0.053), p = 0.026] for self-reported sleep quality, indicating better results in the intervention group compared to controls. CONCLUSION: The educational program improved sleep quality and sleep efficiency while reducing the number of awakenings per night among community-dwelling frail older adults, offering a practical approach to addressing sleep-related challenges in this demographic.

Effect of levetiracetam on DNA oxidation and glutathione content in a temporal lobe epilepsy model.

Levetiracetam (LEV) is a drug commonly used as an anticonvulsant. However, recent evidence points to a possible role as an antioxidant. We previously demonstrated the antioxidant properties of LEV by significantly increasing catalase and superoxide dismutase activities and decreasing the hydrogen peroxide (H2O2) levels in the hippocampus of rats with temporal lobe epilepsy (TLE) showing scavenging properties against the hydroxyl radical. The aim of the present work was to evaluate, the effect of LEV on DNA oxidation, by determining 8­hydroxy­2­deoxyguanosine (8­OHdG) levels, and glutathione content, through reduced (GSH) and oxidized (GSSG) glutathione levels, in the hippocampus of rats with TLE. Male Wistar rats were assigned to the control (CTRL), CTRL+LEV, epileptic (EPI) and EPI+LEV groups. TLE was induced using the lithium­pilocarpine model. Thirteen weeks after TLE induction, LEV was administered for one week through osmotic pumps implanted subcutaneously. The determination of 8­OHdG, GSH and GSSG levels were measured using spectrophotometric methods. We showed that LEV alone significantly increased 8­OHdG and GSSG levels in the hippocampus of control rats compared to those in epileptic condition. No significant differences in GSH levels were observed. LEV could induce changes in the hippocampus increasing DNA oxidation and GSSG levels under nonepileptic condition but not protecting against the mitochondrial dysfunction observed in TLE probably by mechanisms related to changes in chromatin structure, neuroinflammation and alterations in redox components.

Molecular insight into endosulfan degradation by Ese protein from Arthrobacter: Evidence-based structural bioinformatics and quantum mechanical calculations.

Endosulfan is an organochlorine insecticide widely used for agricultural pest control. Many nations worldwide have restricted or completely banned it due to its extreme toxicity to fish and aquatic invertebrates. Arthrobacter sp. strain KW has the ability to degrade α, ß endosulfan and its intermediate metabolite endosulfate; this degradation is associated with Ese protein, a two-component flavin-dependent monooxygenase (TC-FDM). Employing in silico tools, we obtained the 3D model of Ese protein, and our results suggest that it belongs to the Luciferase Like Monooxygenase family (LLM). Docking studies showed that the residues V59, V315, D316, and T335 interact with α-endosulfan. The residues: V59, T60, V315, D316, and T335 are implicated in the interacting site with ß-endosulfan, and the residues: H17, V315, D316, T335, N364, and Q363 participate in the interaction with endosulfate. Topological analysis of the electron density by means of the Quantum Theory of Atoms in Molecules (QTAIM) and the Non-Covalent Interaction (NCI) index reveals that the Ese-ligands complexes are formed mainly by dispersive forces, where Cl atoms have a predominant role. As Ese is a monooxygenase member, we predict the homodimer formation. However, enzymatic studies must be developed to investigate the Ese protein's enzymatic and catalytic activity.

Changes to women's childbirth plans during the COVID-19 pandemic and posttraumatic stress symptoms: a cross-national study.

A considerable number of women giving birth during COVID-19 pandemic reported being concerned about changes to their childbirth plans and experiences due to imposed restrictions. Research prior to the pandemic suggests that women may be more at risk of post-traumatic stress symptoms (PTSS) due to unmet expectations of their childbirth plans. Therefore, this study aimed to examine if the mismatch between women's planned birth and actual birth experiences during COVID-19 was associated with women's postpartum PTSS. Women in the postpartum period (up to 6 months after birth) across 11 countries reported on childbirth experiences, mental health, COVID-19-related factors, and PTSS (PTSD checklist DSM-5 version) using self-report questionnaires (ClinicalTrials.gov: NCT04595123). More than half (64%) of the 3532 postpartum women included in the analysis reported changes to their childbirth plans. All changes were significantly associated with PTSS scores. Participants with one and two changes to their childbirth plans had a 12% and 38% increase, respectively, in PTSS scores compared to those with no changes (Exp(ß) = 1.12; 95% CI [1.06-1.19]; p < 0.001 and Exp(ß) = 1.38; 95% CI [1.29-1.48]; p < 0.001). In addition, the effect of having one change in the childbirth plan on PTSS scores was stronger in primigravida than in multigravida (Exp(ß) = 0.86; 95% CI [0.77-0.97]; p = 0.014). Changes to women's childbirth plans during the COVID-19 pandemic were common and associated with women's postpartum PTSS score. Developing health policies that protect women from the negative consequences of unexpected or unintended birth experiences is important for perinatal mental health.

An Organocopper(III) Fluoride Triggering C-CF3 Bond Formation.

Copper(III) fluorides are catalytically competent, yet elusive, intermediates in cross-coupling. The synthesis of [PPh4 ][CuIII (CF3 )3 F] (2), the first stable (isolable) CuIII -F, was accomplished via chloride addition to [CuIII (CF3 )3 (py)] (1) yielding [PPh4 ][CuIII (CF3 )3 Cl(py)] (1⋅Cl), followed by treatment with AgF. The CuIII halides 1⋅Cl and 2 were fully characterized using nuclear magnetic resonance (NMR) spectroscopy, single crystal X-ray diffraction (Sc-XRD) and elemental analysis (EA). Complex 2 proved capable of forging C-CF3 bonds from silyl-capped alkynes. In-depth mechanistic studies combining probes, theoretical calculations, trapping of intermediate 4a ([PPh4 ][CuIII (CF3 )3 (C≡CPh)]) and radical tests unveil the key role of the CuIII acetylides that undergo facile 2e- reductive elimination furnishing the trifluoromethylated alkynes (RC≡CCF3 ), which are industrially relevant synthons in drug discovery, pharma and agrochemistry.

In silico design of bio-marker detection fluorescent probes.

Fluorescent probes capable of sensing the biological medium are of utmost importance in medical diagnostics. However, the optical spectrum of such probes needs to be tuned with care for compatibility with living tissues. More specifically, fluorescent bioprobes must be adjusted so as to avoid light interference with pigments (e.g. hemoglobin), tissue photodamage, scattering of the emitted light, and autofluorescence. This leads to two important conditions on the optical spectrum of the probes. On the one hand, the emission wavelength must be in an optical window of 650 to 950 nm. On the other hand, the Stokes shift must be large, ideally greater than 150 nm. In this paper, we showcase the in-silico design of potential fluorescent biomarkers fulfilling these two conditions by means of heteroatomic substitution and conjugation on a 1,2,4-triazole core initially far away from biological standards.

Thermoluminescent glow curve of Gd1-xRExAlO3 (RE=Dy or Pr) beta irradiated phosphors.

Phosphors composed of Gd1-xRExAlO3 (0≤x ≤ 5 RE = Dy or Pr) stoichiometries were synthesized using the reverse coprecipitation pathway. The thermoluminescent responses of all phosphors were studied under beta radiation exposure. Doping the gadolinium aluminate host improved the thermoluminescent response of the phosphors, with the phosphors composed of Gd0.99Dy0.01AlO3 and Gd0.95Pr0.05AlO3 being the most sensitive. The Dy3+ ions produced a higher improvement of the thermoluminescent signal than the Pr3+ ions. Additionally, a proportional relationship between the similarity of the atomic numbers of the dopant and replaced ions and the sensitivity to thermoluminescence was confirmed. Besides, a slight shift of the thermoluminescent peaks toward lower temperatures was detected for doped phosphors. In the repeatability tests applied to the phosphor composed of Gd0.99Dy0.01AlO3, an anomalous increase in sensitization was observed. The observed sensitization was associated with the formation of electron trap clusters resulting from the continuous exposure to beta radiation. Furthermore, another sensitization phenomenon was detected in the phosphor with Gd0.95Pr0.05AlO3 stoichiometry when it was heated at low temperatures. The aforementioned striking behavior was related to quasi-continuous distributions of electron traps and the tunneling effect. In regard to linearity, the phosphor composed of Gd0.99Dy0.01AlO3 exhibited a linear response with the dose across the entire range of beta doses. However, the response of the Gd0.95Pr0.05AlO3 phosphor lost linearity beyond 26.4 Gy of beta dose. The results obtained through the use of the Tmax-Tstop method and deconvolutions suggested an enhancement in the efficiency of the thermoluminescent mechanisms due to the incorporation of activators.

The NCIWEB Server: A Novel Implementation of the Noncovalent Interactions Index for Biomolecular Systems.

It is well-known that the activity and function of proteins is strictly correlated with their secondary, tertiary, and quaternary structures. Their biological role is regulated by their conformational flexibility and global fold, which, in turn, is largely governed by complex noncovalent interaction networks. Because of the large size of proteins, the analysis of their noncovalent interaction networks is challenging, but can provide insights into the energetics of conformational changes or protein-protein and protein-ligand interactions. The noncovalent interaction (NCI) index, based on the reduced density gradient, is a well-established tool for the detection of weak contacts in biological systems. In this work, we present a web-based application to expand the use of this index to proteins, which only requires a molecular structure as input and provides a mapping of the number, type, and strength of noncovalent interactions. Structure preparation is automated and allows direct importing from the PDB database, making this server (https://nciweb.dsi.upmc.fr) accessible to scientists with limited experience in bioinformatics. A quick overview of this tool and concise instructions are presented, together with an illustrative application.

Antiangiogenic Effect of Dopamine and Dopaminergic Agonists as an Adjuvant Therapeutic Option in the Treatment of Cancer, Endometriosis, and Osteoarthritis.

Dopamine (DA) and dopamine agonists (DA-Ag) have shown antiangiogenic potential through the vascular endothelial growth factor (VEGF) pathway. They inhibit VEGF and VEGF receptor 2 (VEGFR 2) functions through the dopamine receptor D2 (D2R), preventing important angiogenesis-related processes such as proliferation, migration, and vascular permeability. However, few studies have demonstrated the antiangiogenic mechanism and efficacy of DA and DA-Ag in diseases such as cancer, endometriosis, and osteoarthritis (OA). Therefore, the objective of this review was to describe the mechanisms of the antiangiogenic action of the DA-D2R/VEGF-VEGFR 2 system and to compile related findings from experimental studies and clinical trials on cancer, endometriosis, and OA. Advanced searches were performed in PubMed, Web of Science, SciFinder, ProQuest, EBSCO, Scopus, Science Direct, Google Scholar, PubChem, NCBI Bookshelf, DrugBank, livertox, and Clinical Trials. Articles explaining the antiangiogenic effect of DA and DA-Ag in research articles, meta-analyses, books, reviews, databases, and clinical trials were considered. DA and DA-Ag have an antiangiogenic effect that could reinforce the treatment of diseases that do not yet have a fully curative treatment, such as cancer, endometriosis, and OA. In addition, DA and DA-Ag could present advantages over other angiogenic inhibitors, such as monoclonal antibodies.

Estrogens as a Possible Therapeutic Strategy for the Management of Neuroinflammation and Neuroprotection in COVID-19.

The Coronavirus disease 2019 (COVID-19) affects several tissues, including the central and peripheral nervous system. It has also been related to signs and symptoms that suggest neuroinflammation with possible effects in the short, medium, and long term. Estrogens could have a positive impact on the management of the disease, not only due to its already known immunomodulator effect, but also activating other pathways that may be important in the pathophysiology of COVID-19, such as the regulation of the virus receptor and its metabolites. In addition, they can have a positive effect on neuroinflammation secondary to pathologies other than COVID-19. The aim of this study is to analyze the molecular mechanisms that link estrogens with their possible therapeutic effect for neuroinflammation related to COVID-19. Advanced searches were performed in scientific databases as Pub- Med, ProQuest, EBSCO, the Science Citation index, and clinical trials. Estrogens have been shown to participate in the immune modulation of the response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In addition to this mechanism, we propose that estrogens can regulate the expression and activity of the Angiotensin-converting enzyme 2 (ACE2), reestablishing its cytoprotective function, which may be limited by its interaction with SARS-CoV-2. In this proposal, estrogens and estrogenic compounds could increase the synthesis of Angiotensin-(1-7) (Ang-(1-7)) that acts through the Mas receptor (MasR) in cells that are being attacked by the virus. Estrogens can be a promising, accessible, and low-cost treatment for neuroprotection and neuroinflammation in patients with COVID-19, due to its direct immunomodulatory capacity in decreasing cytokine storm and increasing cytoprotective capacity of the axis ACE2/Ang (1-7)/MasR.

Does the psychoemotional well-being of Spanish students influence their mathematical literacy? An evidence from PISA 2018.

Data from international studies reveal that the mathematics literacy of Spanish students is significantly lower than that of students from nearby countries. Therefore, in recent years, interest in identifying the factors that influence students' mathematics results in Spain has grown considerably. Often, these factors are sought among the socioeconomic characteristics of the students or among variables related to the schools, ignoring the psychological and emotional factors of the students. This paper analyzes the impact of certain psychoemotional characteristics of Spanish students on their literacy in mathematics. For this purpose, multilevel regression models are applied to the data of the Spanish sample of the 2018 edition of PISA (Programme for International Student Assessment), which is composed of 35,943 15-year-old students. The instruments for data collection are the mathematics literacy tests and the contextual questionnaires on students' personal situation and well-being used by PISA. As dependent variable, students' mathematics literacy has been considered, measured through the plausible values provided by PISA, and as independent variables, different indices measuring students' psychoemotional well-being obtained from the contextual information collected by PISA. Results indicate that resilience, motivation for the achievement of learning objectives, competitiveness, perceived cooperation at school, and social connectedness with parents have a positive impact on students' mathematics literacy, while experiences related to bullying, physical self-concept, meaning in life and perceived competitiveness at school have a negative impact.

Evaluation of the Antioxidant Activity of Levetiracetam in a Temporal Lobe Epilepsy Model.

Epilepsy is a neurological disorder in which it has been shown that the presence of oxidative stress (OS) is implicated in epileptogenesis. The literature has shown that some antiseizure drugs (ASD) have neuroprotective properties. Levetiracetam (LEV) is a drug commonly used as an ASD, and in some studies, it has been found to possess antioxidant properties. Because the antioxidant effects of LEV have not been demonstrated in the chronic phase of epilepsy, the objective of this study was to evaluate, for the first time, the effects of LEV on the oxidant-antioxidant status in the hippocampus of rats with temporal lobe epilepsy (TLE). The in vitro scavenging capacity of LEV was evaluated. LEV administration in rats with TLE significantly increased superoxide dismutase (SOD) activity, increased catalase (CAT) activity, but did not change glutathione peroxidase (GPx) activity, and significantly decreased glutathione reductase (GR) activity in comparison with epileptic rats. LEV administration in rats with TLE significantly reduced hydrogen peroxide (H2O2) levels but did not change lipoperoxidation and carbonylated protein levels in comparison with epileptic rats. In addition, LEV showed in vitro scavenging activity against hydroxyl radical (HO•). LEV showed significant antioxidant effects in relation to restoring the redox balance in the hippocampus of rats with TLE. In vitro, LEV demonstrated direct antioxidant activity against HO•.

A cross-country study on the impact of governmental responses to the COVID-19 pandemic on perinatal mental health.

This study aimed to analyse the role of governmental responses to the coronavirus disease 2019 (COVID-19) outbreak, measured by the Containment and Health Index (CHI), on symptoms of anxiety and depression during pregnancy and postpartum, while considering the countries' Inequality-adjusted Human Development Index (IHDI) and individual factors such as age, gravidity, and exposure to COVID-19. A cross-sectional study using baseline data from the Riseup-PPD-COVID-19 observational prospective international study (ClinicalTrials.gov: NCT04595123) was carried out between June and October 2020 in 12 countries (Albania, Brazil, Bulgaria, Chile, Cyprus, Greece, Israel, Malta, Portugal, Spain, Turkey, and the United Kingdom). Participants were 7645 pregnant women or mothers in the postpartum period-with an infant aged up to 6 months-who completed the Edinburgh Postnatal Depression Scale (EPDS) or the Generalised Anxiety Disorder Assessment (GAD-7) during pregnancy or the postpartum period. The overall prevalence of clinically significant depression symptoms (EPDS ≥ 13) was 30%, ranging from 20,5% in Cyprus to 44,3% in Brazil. The prevalence of clinically significant anxiety symptoms (GAD-7 ≥ 10) was 23,6% (ranging from 14,2% in Israel and Turkey to 39,5% in Brazil). Higher symptoms of anxiety or depression were observed in multigravida exposed to COVID-19 or living in countries with a higher number of deaths due to COVID-19. Furthermore, multigravida from countries with lower IHDI or CHI had higher symptoms of anxiety and depression. Perinatal mental health is context-dependent, with women from more disadvantaged countries at higher risk for poor mental health. Implementing more restrictive measures seems to be a protective factor for mental health, at least in the initial phase of the COVID-19.

The impact of COVID-19 on breastfeeding rates: An international cross-sectional study.

BACKGROUND: Breastfeeding promotes children's health and is associated with positive effects to maternal physical and mental health. Uncertainties regarding SARS-CoV-2 transmission led to worries experienced by women and health professionals which impacted breastfeeding plans. We aimed to investigate the impact of self-reported and country-specific factors on breastfeeding rates during the COVID-19 pandemic. METHODS: This study is part of a broader international prospective cohort study about the impact of the COVID-19 pandemic on perinatal mental health (Riseup-PPD-COVID-19). We analysed data from 5612 women, across 12 countries. Potential covariates of breastfeeding (sociodemographic, perinatal, physical/mental health, professional perinatal care, changes in healthcare due to the pandemic, COVID-19 related, breastfeeding support, governmental containment measures and countries' inequality levels) were studied by Generalized Linear Mixed-Effects Models. RESULTS: A model encompassing all covariates of interest explained 24% of the variance of breastfeeding rates across countries (first six months postpartum). Overall, first child (ß = -0.27), age of the child (ß = -0.29), preterm birth (ß = -0.52), admission to the neonatal/pediatric care (ß = -0.44), lack of breastfeeding support (ß = -0.18), current psychiatric treatment (ß = -0.69) and inequality (ß = -0.71) were negatively associated with breastfeeding (p < .001). Access to postnatal support groups was positively associated with breastfeeding (ß = 0.59; p < .001). In countries with low-inequality, governmental measures to contain virus transmission had a deleterious effect on breastfeeding (ß = -0.16; p < .05) while access to maternity leave protected breastfeeding (ß = 0.50; p < .001). DISCUSSION: This study shows that mother's COVID-19 diagnosis and changes in healthcare and birth/postnatal plans did not influence breastfeeding rates. Virtual support groups help women manage breastfeeding, particularly when their experiencing a first child and for those under psychiatric treatment. The complex associations between covariates and breastfeeding vary across countries, suggesting the need to define context-specific measures to support breastfeeding.