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Nature of the dative Nitrogen-Coinage metal bond in molecular Motors. Evaluation of NHC-M pyrazine bond (M = Cu, Ag, Au) from relativistic DFT
No full textThe use of different N-heterocyclic carbene (NHC) coordinated to coinage metals are useful caps for generating mechanical bonds towards donor-nitrogen fragments, leading to the characterization of efficient molecular motors. Here, we account for the nature of the formation of mechanical bonds on [(NHC-M)2pyz]2+ (M = Cu, Ag, Au; pyz = pyrazine) complexes. The NHC-M pyrazine interaction is of main electrostatic character given by the Lewis acidic σ-hole characteristics of the NHC-M caps, and the Lewis basic features of the aromatic pyrazine ring, accounting for the 69.9 %, 71.8 %, and 68.8 %, for Cu, Ag, and Au species, respectively. The rotational barrier is calculated at 10.2, 8.6, and 6.0 kcal mol−1, respectively, which is given by the variation of the NHC-M pyrazine interaction, and structural arrangements, accounting for 54.0/46.0 %, 59.3/40.7 %, and, 79.8/20.2 %, for Cu, Ag, and Au, respectively. Hence, the rotational barrier for the gold counterpart is less affected by structural factors. Relativistic effects on the N-coinage metal bond interaction are crucial for the account of the experimentally observed rotational barrier. Thus, the theoretical evaluation of mechanical bonds allows to gain further insights into the fundamental nature of the interaction and how structural factors affect the formation of molecular motors relevant to guide design and synthetic efforts.Universidad Autónoma de Chil
Phenolic Profile and Cholinesterase Inhibitory Properties of Three Chilean Altiplano Plants: Clinopodium gilliesii (Benth.) Kuntze [Lamiaceae], Mutisia acuminata Ruiz & Pav. var. hirsuta (Meyen) Cabrera, and Tagetes multiflora (Kunth) [Asteraceae]
No full textThis research aimed to identify the phenolic profile and composition of the aerial parts of three native species used in traditional medicine in the Andean Altiplano of northern Chile: Clinopodium gilliesii (Benth.) Kuntze [Lamiaceae] (commonly known as Muña-Muña), Mutisia acuminata Ruiz & Pav. var. hirsuta (Meyen) Cabrera [Asteraceae] (commonly known as Chinchircoma), and Tagetes multiflora (Kunth), [Asteraceae] (commonly known as Gracilis), as well as to evaluate their potential inhibitory effects against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Polyphenolic enriched-extracts (PEEs) of the species were prepared and analyzed and the main components were quantified using HPLC-DAD. In total, 30 phenolic compounds were identified and quantified in all species, including simple phenolics, hydroxycinnamic acids, flavan-3-ols (monomers and polymers), flavanones, and flavonols. In addition, other main phenolics from the extracts were tentatively identified by ESI-MS-MS high-resolution analysis. T. multiflora extract showed the greatest anti-AChE and BChE activity in comparison with C. gilliesii and M. acuminata extracts, being the anti-AChE and BChE activity weak in all extracts in comparison to galantamine control. To comprise to better understand the interactions between cholinesterase enzymes and the main phenolics identified in T. multiflora, molecular docking analysis was conducted. © 2023 by the authors.Universidad Autónoma de Chil
Protein kinase B (AKT) upregulation and Thy-1-αvβ3 integrin-induced phosphorylation of Connexin43 by activated AKT in astrogliosis
No full textBackground: In response to brain injury or inflammation, astrocytes undergo hypertrophy, proliferate, and migrate to the damaged zone. These changes, collectively known as "astrogliosis", initially protect the brain; however, astrogliosis can also cause neuronal dysfunction. Additionally, these astrocytes undergo intracellular changes involving alterations in the expression and localization of many proteins, including αvβ3 integrin. Our previous reports indicate that Thy-1, a neuronal glycoprotein, binds to this integrin inducing Connexin43 (Cx43) hemichannel (HC) opening, ATP release, and astrocyte migration. Despite such insight, important links and molecular events leading to astrogliosis remain to be defined. Methods: Using bioinformatics approaches, we analyzed different Gene Expression Omnibus datasets to identify changes occurring in reactive astrocytes as compared to astrocytes from the normal mouse brain. In silico analysis was validated by both qRT-PCR and immunoblotting using reactive astrocyte cultures from the normal rat brain treated with TNF and from the brain of a hSOD1G93A transgenic mouse model. We evaluated the phosphorylation of Cx43 serine residue 373 (S373) by AKT and ATP release as a functional assay for HC opening. In vivo experiments were also performed with an AKT inhibitor (AKTi). Results: The bioinformatics analysis revealed that genes of the PI3K/AKT signaling pathway were among the most significantly altered in reactive astrocytes. mRNA and protein levels of PI3K, AKT, as well as Cx43, were elevated in reactive astrocytes from normal rats and from hSOD1G93A transgenic mice, as compared to controls. In vitro, reactive astrocytes stimulated with Thy-1 responded by activating AKT, which phosphorylated S373Cx43. Increased pS373Cx43 augmented the release of ATP to the extracellular medium and AKTi inhibited these Thy-1-induced responses. Furthermore, in an in vivo model of inflammation (brain damage), AKTi decreased the levels of astrocyte reactivity markers and S373Cx43 phosphorylation. Conclusions: Here, we identify changes in the PI3K/AKT molecular signaling network and show how they participate in astrogliosis by regulating the HC protein Cx43. Moreover, because HC opening and ATP release are important in astrocyte reactivity, the phosphorylation of Cx43 by AKT and the associated increase in ATP release identify a potential therapeutic window of opportunity to limit the adverse effects of astrogliosis. © 2023, The Author(s).AFGQ, (1181645, 1190833); BvZ, (1191928); CONICYT-FONDAP, (15130011); ICM-ANID, (09-022, ACT-1114, ATA 2014-F-034); ALS Therapy Alliance; Desert Research Institute, DRI, (USA 2013-0030); Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, SNF, (31003-176256, DIUA 169-2019); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1170925, 1200836, 1210644, 3170645); Agencia Nacional de Investigación y Desarrollo, ANID, (AHC), Anillo ACT-1114, CONICYT-FONDAP #15130011 (AFGQ, FONDECYT #1190833 (PRM), FONDECYT #1191928 (AHC), FONDECYT #1200836 (LL), FONDECYT #3170645 (RP), and DRI USA 2013-0030 (BvZ))Universidad Autónoma de Chil
Editorial: Neurological comorbidity in metabolic syndrome
No full text[No abstract available]Universidad Autónoma de Chil
Skeletal Muscle Atrophy Induced by Diabetes Is Mediated by Non-Selective Channels and Prevented by Boldine
No full textIndividuals with diabetes mellitus present a skeletal muscle myopathy characterized by atrophy. However, the mechanism underlying this muscular alteration remains elusive, which makes it difficult to design a rational treatment that could avoid the negative consequences in muscles due to diabetes. In the present work, the atrophy of skeletal myofibers from streptozotocin-induced diabetic rats was prevented with boldine, suggesting that non-selective channels inhibited by this alkaloid are involved in this process, as has previously shown for other muscular pathologies. Accordingly, we found a relevant increase in sarcolemma permeability of skeletal myofibers of diabetic animals in vivo and in vitro due to de novo expression of functional connexin hemichannels (Cx HCs) containing connexins (Cxs) 39, 43, and 45. These cells also expressed P2X7 receptors, and their inhibition in vitro drastically reduced sarcolemma permeability, suggesting their participation in the activation of Cx HCs. Notably, sarcolemma permeability of skeletal myofibers was prevented by boldine treatment that blocks Cx43 and Cx45 HCs, and now we demonstrated that it also blocks P2X7 receptors. In addition, the skeletal muscle alterations described above were not observed in diabetic mice with myofibers deficient in Cx43/Cx45 expression. Moreover, murine myofibers cultured for 24 h in high glucose presented a drastic increase in sarcolemma permeability and levels of NLRP3, a molecular member of the inflammasome, a response that was also prevented by boldine, suggesting that, in addition to the systemic inflammatory response found in diabetes, high glucose can promote the expression of functional Cx HCs and activation of the inflammasome in skeletal myofibers. Therefore, Cx43 and Cx45 HCs play a critical role in myofiber degeneration, and boldine could be considered a potential therapeutic agent to treat muscular complications due to diabetes. © 2023 by the authors.DIUA, (264-2023); ICM-ANID, (P09-022-); Vicerrectoría de Investigación y Postgrado; Universidad Autónoma de Coahuila, UAdeC; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231523)Universidad Autónoma de Chil
Commitment and Job Satisfaction Older Workers People in a Municipality in South-Central Chile
No full textThis work is part of a broader investigation called diagnosis of labor relations with a gender perspective carried out in a municipality in south-central Chile, in the context of reducing gender inequalities in the workplace. This research is of a quantitative nature and the population was 1255 officials, for which a sample of 365 people of different age groups was used. The analyzes are descriptive statistics and frequency tables and graphs are used. The results of this specific study of the elderly point to a high degree of job satisfaction and perception of a positive work environment. In this line, the data show that the older civil servants of this municipality do not feel discriminated against and do not stand out suffering situations of workplace violence, presenting similar percentages in all the age groups that were part of the sample. At the same time, these same data point to a positive perception of gender gaps in the workplace.Universidad Autónoma de Chil
Development of a Web-Based System to Measure, Monitor and Promote School Engagement Strategies
No full textThis article presents an intervention model to promote positive educational trajectories based on technology and available evidence on educational engagement's predictive capacity to influence students’ educational trajectories in schools with high social vulnerability both in Chile and Latin America. The software-based model was developed through collaborative work between the university, IT team, educational communities, and stakeholders (governmental institutions). It is a web-based system composed of six steps whose axis centers on a decision-making space between teachers-students-parents (School Engagement Board) tasked with applying online and scientifically validated school engagement measurement instruments, checking specific report results for each actor involved into the system (teacher, school engagement board coordinator, school) as well as reviewing advocacy strategies that are pertinent to school context and manage strategy implementation supported by the management sheets that the model offers to schools.Universidad Autónoma de Chil
Precisión en la exploración de la composición corporal mediante DXA de medio cuerpo en adultos
No full textIntroduction: dual-energy X-ray absorptiometry (DXA) is the gold standard method, although one limitation is the size of the scan area. Objective: the objective was to verify the accuracy of body composition (BC) scanning through half-body DXA scanning compared to standard total body scanning. Methods: a study was conducted on 145 volunteers. Weight and height were assessed. Body mass index (BMI) was calculated. DXA was used for whole-body scan (WBS) and half-body scan (HBS). WBS was used as the reference method and the following indicators were extracted: bone mineral content (BMC), fat mass (FM), lean soft tissue (LST) and percentage fat mass (%FM). Results: no differences were observed in the body composition indicators (BMC, FM, LST and %FM) when compared between the reference WBS scanner and the HBS scanner. The predictive power between both scans ranged in both sexes between R2 = 0.94 and 0.98. The DRI desirable reproducibility index values defining the degree of agreement between both scans ranged from 0.97 to 0.99, and the values for precision (0.97 to 0.99) and accuracy (0.99) were high. Conclusion: HBS scanning by DXA evidenced agreement, and high values of accuracy and precision to assess body composition indicators (BMC, FM, LST and %FM). © 2023 SENPE and Arán Ediciones S.L.Universidad Autónoma de Chil
The Obesity Paradox: Associations between the Body Mass Index and Self-Perceived Health, Depression Status, and Pain Level in Older People
No full textPopulation growth and physical inactivity have led to health and social consequences derived from chronic diseases and decreased quality of life in the elderly. Some research suggests that overweight in older people may not be associated with the negative effects on some health indicators. This study analysed the associations between Self-Perceived Health (SPH), Depression status, Pain Level, and Body Mass Index (BMI) in people over 70 years who are residents in Spain, with a final sample composed of 13,895 participants. A cross-sectional study using data from the European Health Surveys in Spain (EHIS2014 and 2020) and the National Health Survey (ENSE2017) was conducted. Dependency associations were observed between SPH, Depression Status, and Pain Level with BMI in the outcomes from the three surveys analysed (p < 0.001). Negative SPH, Depression Status, and Severe/Extreme Pain Degree prevalence were higher in the Underweight groups, being the lowest in Normal-weight and Overweight groups (p < 0.05). High levels of negative SPH, Depression, and Severe/Extreme Pain risks were found in the Underweight compared to the Normal-weight group, but not in Overweight ones. Overweight was not linked with an increased risk of the conditions analysed compared to the Normal-weight groups in older residents in Spain. The Underweight group presented the highest negative SPH prevalence, Depression, and Severe/Extreme Pain. Moreover, Obesity increased the negative SPH, Depression, and Pain Degree risks compared to the Normal-weight and Overweight groups in this population. © 2022 by the authors.Ministerio de Educación, Cultura y Deporte, MECD, (MCIN/AEI/10.13039/501100011033); European Social Fund, ESFUniversidad Autónoma de Chil
Diagnosis and Treatment in Unilateral Condylar Hyperplasia
No full textUnilateral condylar hyperplasia (UCH) is an uncommon disease involving progressive facial asymmetry. The aim of this research was to perform an analysis of the diagnosis and treatment of patients with UCH in a clinical series. An observational retrospective study was performed on subjects with progressive facial asymmetry in the lower third of the face; all the subjects were under treatment with condylectomy and orthodontics to improve occlusion and face balance. Variables such as age, sex, clinical type, SPECT (single photon emission computed tomography) intensity and a requirement for secondary surgery were included; the Shapiro Wilk test was performed to analyze the normality of the data and nonparametric analysis and the Kruskal-Wallis or Mann-Whitney tests were used to assess the association between the SPECT difference and the variables, where 2-tailed p values < 0.05 were considered to be statistically significant. Forty-nine patients between 10 and 45 y.o. (average age: 19.1 ± 7.4 y.o.) were included in the study. There were 41 female (83.6%) and 8 male (16.4%) subjects. The SPECT analysis comparing the right and left condyles with more than 10% in caption of the isotope was present in 46 subjects; the results obtained using SPECT were not statistically related to the age or sex of the sample (p = 0.277). The patients were classified into clinical types I, II and III, and no correlations could be confirmed between the clinical type and other variables. High condylectomy was conducted on all patients, among which 14 patients underwent a secondary surgery for orthognathic or cosmetic treatment, and was not related to the initial variables used in diagnosis (p = 0.98); interestingly, the second surgical treatment was more present in the clinical type I and in subjects under 16 years old with no statistical differences. Clinical analysis, medical records, 3D imaging and SPECT should be used as a complementary analysis in assessing the diagnosis of UCH and progressive facial asymmetry.Universidad Autónoma de Chil