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1.
Chemistry ; 30(31): e202401164, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38551412

RESUMEN

Convenient self-assembly synthesis of copper(II) complexes via double (phenylsilsesquioxane and acetate) ligation allows to isolate a family of impressive sandwich-like cage compounds. An intriguing feature of these complexes is the difference in the structure of a pair of silsesquioxane ligands despite identical (Cu6) nuclearity and number (four) of acetate fragments. Formation of particular combination of silsesquioxane ligands (cyclic/cyclic vs condensed/condensed vs cyclic/condensed) was found to be dependent on the synthesis/crystallization media. A combination of Si4-cyclic and Si6-condensed silsesquioxane ligands is a brand new feature of cage metallasilsesquioxanes. A representative Cu6-complex (4) (with cyclic silsesquioxanes) exhibited high catalytic activity in the oxidation of alkanes and alcohols with peroxides. Maximum yield of the products of cyclohexane oxidation attained 30 %. The compound 4 was also tested as catalyst in the Baeyer-Villiger oxidation of cyclohexanone by m-chloroperoxybenzoic acid: maximum yields of 88 % and 100 % of ϵ-caprolactone were achieved upon conventional heating at 50 °C for 4 h and MW irradiation at 70 or 80 °C during 30 min, respectively. It was also possible to obtain the lactone (up to 16 % yield) directly from the cyclohexane via a tandem oxidation/Baeyer-Villiger oxidation reaction using the same oxidant.

2.
J Dairy Sci ; 107(6): 3794-3801, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38310969

RESUMEN

Over the past decades, daughter designs, including genotyped sires and their genotyped daughters, have been used as an approach to identify QTL related to economic traits. The aim of this study was to identify genomic regions inherited by Gir sire families and genes associated with number of viable oocytes (VO), total number of oocytes (TO), and number of embryos (EMBR) based on a daughter design approach. In total, 15 Gir sire families were selected. The number of daughters per family ranged from 26 to 395, which were genotyped with different SNP panels and imputed to the Illumina BovineHD BeadChip (777K) and had phenotypes for oocyte and embryo production. Daughters had phenotypic data for VO, TO, and EMBR. The search for QTL was performed through GWAS based on GBLUP. The QTL were found for each trait among and within families based on the top 10 genomic windows with the greatest genetic variance. For EMBR, genomic windows identified among families were located on BTA4, BTA5, BTA6, BTA7, BTA8, BTA13, BTA16, and BTA17, and they were most frequent on BTA7 within families. For VO, genomic windows were located on BTA2, BTA4, BTA5, BTA7, BTA17, BTA21, BTA22, BTA23, and BTA27 among families, being most frequent on BTA8 within families. For TO, the top 10 genomic windows were identified on BTA2, BTA4, BTA5, BTA7, BTA17, BTA21, BTA22, BTA26, and BTA27, being most frequent on BTA7 and BTA8 within families. Considering all results, the greatest number of genomic windows was found on BTA7, where the VCAN, XRCC4, TRNAC-ACA, HAPLN1, and EDIL3 genes were identified in the common regions. In conclusion, 15 Gir sire families with 26 to 395 daughters per family with phenotypes for oocyte and embryo production helped to identify the inheritance of several genomic regions, especially on BTA7, where the EDIL3, HAPLN1, and VCAN candidate genes were associated with number of oocytes and embryos in Gir cattle families.


Asunto(s)
Genotipo , Oocitos , Fenotipo , Animales , Bovinos/genética , Femenino , Sitios de Carácter Cuantitativo , Masculino , Genoma , Genómica , Cruzamiento , Estudio de Asociación del Genoma Completo/veterinaria , Polimorfismo de Nucleótido Simple
3.
Inorg Chem ; 62(33): 13573-13586, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37561666

RESUMEN

A small family of nonanuclear Cu5Cs4-based phenylsilsesquioxanes 1-2 were prepared by a convenient self-assembly approach and characterized by X-ray diffraction studies. The compounds 1 and 2 show some unprecedented structural features such as the presence of a [Ph14Si14O28]14- silsesquioxane ligand and a CuII5CsI4 nuclearity in which the metal cations occupy unusual positions within the cluster. Copper ions are "wrapped" into a silsesquioxane matrix, while cesium ions are located in external positions. This resulted in cesium-involved aggregation of coordination polymer structures. Both compounds 1 and 2 realize specific metallocene (cesium-phenyl) linkage between neighboring cages. Compound 2 is evaluated as a catalyst in the Baeyer-Villiger (B-V) oxidation of cyclohexanone and tandem cyclohexane oxidation/B-V oxidation of cyclohexanone with m-chloroperoxybenzoic acid (mCPBA) as an oxidant, in an aqueous acetonitrile medium, and HNO3 as the promoter. A quantitative yield of ε-caprolactone was achieved under conventional heating at 50 °C for 4 h or MW irradiation for 30 min (for cyclohexanone as substrate); 17 and 19% yields of lactone upon MW irradiation at 80 °C for 30 min and heating at 50 °C for 4 h, respectively (for cyclohexane as a substrate), were achieved. Complex 2 was evaluated as a catalyst for the oxidation of alkanes to alkyl hydroperoxides and alcohols to ketones with peroxides at 60 °C in acetonitrile. The maximum yield of cyclohexane oxidation products was 30%. Complex 2 exhibits high activity in the oxidation of alcohols.

4.
Public Health ; 220: 148-154, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37320945

RESUMEN

OBJECTIVES: The study investigated the longitudinal association between physical activity and the risk of long COVID in patients who recovered from COVID-19 infection. STUDY DESIGN: We analyzed longitudinal data of the Prospective Study About Mental and Physical Health cohort, a prospective cohort study with adults living in Southern Brazil. METHODS: Participants responded to an online, self-administered questionnaire in June 2020 (wave 1) and June 2022 (wave 4). Only participants who self-reported a positive test for COVID-19 were included. Physical activity was assessed before (wave 1, retrospectively) and during the pandemic (wave 1). Long COVID was assessed in wave 4 and defined as any post-COVID-19 symptoms that persisted for at least 3 months after infection. RESULTS: A total of 237 participants (75.1% women; mean age [standard deviation]: 37.1 [12.3]) were included in this study. The prevalence of physical inactivity in baseline was 71.7%, whereas 76.4% were classified with long COVID in wave 4. In the multivariate analysis, physical activity during the pandemic was associated with a reduced likelihood of long COVID (prevalence ratio [PR]: 0.83; 95% confidence interval [CI]: 0.69-0.99) and a reduced duration of long COVID symptoms (odds ratio: 0.44; 95% CI: 0.26-0.75). Participants who remained physically active from before to during the pandemic were less likely to report long COVID (PR: 0.74; 95% CI: 0.58-0.95), fatigue (PR: 0.49; 95% CI: 0.32-0.76), neurological complications (PR: 0.47; 95% CI: 0.27-0.80), cough (PR: 0.40; 95% CI: 0.22-0.71), and loss of sense of smell or taste (PR: 0.43; 95% CI: 0.21-0.87) as symptom-specific long COVID. CONCLUSION: Physical activity practice was associated with reduced risk of long COVID in adults.


Asunto(s)
COVID-19 , Síndrome Post Agudo de COVID-19 , Humanos , Adulto , Femenino , Masculino , COVID-19/epidemiología , Estudios Prospectivos , Estudios Retrospectivos , Ejercicio Físico
5.
Conscious Cogn ; 101: 103332, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35453102

RESUMEN

Fluctuating between external conscious processing and mind wandering is inherent to the human condition. Past research showed that in tasks requiring sustained attention, mind wandering episodes in which attention is directed internally constrain conscious processing of external stimuli. Conversely, conscious processing of internal stimuli is enhanced during mind wandering. To investigate this, we developed and administered a visuomotor tracking task in which participants were instructed to track the path of a stimulus on a screen with a mouse while responding to rare targets. Prior to reports of mind wandering we found the following: The P3 event-related potential component for targets, indicative of conscious stimulus processing, was attenuated at electrodes Cz and Pz. Moreover, alpha power, indicative of internal mental states, increased globally. Theta power increased along the centroparietal area, and beta decreased along right frontal and right centroparietal areas. Interestingly, trait mind wandering was positively correlated with delta power and gamma power, but negatively correlated with the theta-beta ratio. These results demonstrate that mind wandering is characterized by distinct neural signatures at both a state and trait level.


Asunto(s)
Atención , Estado de Conciencia , Electroencefalografía , Humanos
6.
J Endocrinol Invest ; 45(10): 1875-1885, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35689728

RESUMEN

PURPOSE: The use of sex steroids by trans people has been of paramount importance regarding body changes during gender transition. The objective of this study was to assess the effects of an injectable steroid combination frequently used by transwomen, namely estradiol enanthate with dihydroxyprogesterone acetophenide (E2EN/DHPA), on blood pressure and metabolic outcomes using an animal model. METHODS: Two-month-old male Wistar rats were orchiectomized or sham-operated and divided into groups: (1) Sham treated with sesame oil vehicle (SG), (2) sham treated with E2EN/DHPA (SP), (3) orchiectomized rats treated with vehicle (OG), and (4) orchiectomized rats treated with E2EN/DHPA (OP), with all groups treated every 10 days for 5 months. We evaluated systolic blood pressure (SBP), body weight (BW), abdominal circumference, nasoanal length (NAL), food and water intake (FI, WI), lipid profile (triglycerides, LDL, and HDL), serum C-reactive protein (CRP), plasma concentrations of urea (URpl) and creatinine (CRpl), 24 h urinary volume (V24 h), sodium and potassium excretion (UNa+, UK+), and proteinuria. RESULTS: E2EN/DHPA administration reduced BW (SP 324.5 ± 31.1; OP 291.7 ± 41.3 g) and NAL (SP 24.5 ± 0.4; OP 24.6 ± 1.0 cm), without changing blood pressure, but increased URpl concentration (SP 55.0 ± 4.8; OP 42.5 ± 8.8 mg/dL) and CRpl (SP 0.47 ± 0.05; OP 0.46 ± 0.04 mg/dL), sodium (SP 3.1 ± 0.8; OP 3.3 ± 0.4 µEq/min/kg), potassium (SP 0.91 ± 0.22; OP 0.94 ± 0.22 µEq/min/kg) excretions and urinary volume (SP 15.5 ± 2.1; OP 16.4 ± 2.9 mL/24 h). CONCLUSION: Cross-sex hormone therapy with E2EN/DHPA significantly modified body characteristics in male rats, producing a feminizing change without altering blood pressure or generating harmful metabolic parameters, but larger translational studies are still needed.


Asunto(s)
Progestinas , Roedores , Animales , Presión Sanguínea/fisiología , Peso Corporal , Estrógenos/farmacología , Humanos , Masculino , Potasio/farmacología , Progestinas/farmacología , Ratas , Ratas Wistar , Sodio
7.
Lett Appl Microbiol ; 74(6): 981-991, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35247276

RESUMEN

The antibacterial activity of citrus essential oils (EOs) in the context of combating Limosilactobacillus fermentum, one of the most important bacterial contaminants in the bioethanol production industry, has never been explored previously. Industrial processes usually utilize sulfuric acid for cell treatment to decrease bacterial contamination. However, due to the hazardous nature of sulfuric acid, an alternative to it is highly desirable. Therefore, in the present study, the efficacy of Fremont IAC 543 mandarin EO against a strain of L. fermentum (ATCC® 9338™) was evaluated under proliferative/nonproliferative conditions, in both pure culture and co-culture with an industrial strain of Saccharomyces cerevisiae. The mandarin EO exhibited higher effectiveness against L. fermentum compared to that against S. cerevisiae under nonproliferative conditions (added to water rather than to culture medium). At the concentration of 0·05%, the EO was as effective as the acid solution with pH 2·0 in reducing the count of L. fermentum almost 5 log CFU ml-1 cycles, while the concentration of 0·1% led to the complete loss of bacterial culturability. When L. fermentum was co-cultured with S. cerevisiae, the efficacy of the EO against the bacterial strain was reduced. However, despite this reduced efficacy in co-culture, mandarin EO may be considered effective in combating L. fermentum and could be applied in processes where this bacterium proves to be unfavourable and does not interact with S. cerevisiae.


Asunto(s)
Limosilactobacillus fermentum , Aceites Volátiles , Antibacterianos/metabolismo , Etanol/metabolismo , Fermentación , Microbiología Industrial , Limosilactobacillus fermentum/metabolismo , Aceites Volátiles/farmacología , Saccharomyces cerevisiae/metabolismo
8.
Public Health ; 209: 61-66, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35820356

RESUMEN

OBJECTIVES: It has been suggested that contextual factors may be related to obesity; however, they have not yet been widely investigated. The main objective of this ecological time-series study was to analyse factors associated with the increase in obesity in the adult and elderly population in Brazil from 2006 to 2020. STUDY DESIGN: This is an ecological time-series study. Data were collected by the Surveillance System for Risk and Protection Factors for Chronic Diseases by Telephone Survey (VIGITEL), the main health survey in Brazil. METHODS: The outcome was the annual obesity growth rate (in percentage points). Independent variables were behavioural and contextual factors. Data analysis was performed using Prais-Winsten regression for temporal analyses, and Spearman correlation and crude and adjusted linear regression (beta and 95% confidence intervals [CIs]). RESULTS: The annual obesity growth rate was 0.58 percentage points (p.p.) (95% CI: 0.54; 0.63) per year. Demographic density and the percentage of the population employed showed an inverse association with the growth of obesity. Variables such as Gross Domestic Product (GDP) per capita, Gini coefficient, urbanisation rate, percentage of the population with low level of education and percentage of the population without an income were directly associated with the increase in obesity rates. The variables maintained in the final model explained 81% of the growth in obesity in Brazil over the last 15 years (2006-2020). CONCLUSIONS: The growth of obesity in Brazil was mostly explained by contextual factors, especially those of a socio-economic nature. Therefore, interventions to mitigate the increase in obesity must go beyond behavioural factors.


Asunto(s)
Renta , Obesidad , Adulto , Anciano , Brasil/epidemiología , Producto Interno Bruto , Encuestas Epidemiológicas , Humanos , Obesidad/epidemiología , Factores Socioeconómicos
9.
Public Health ; 204: 14-20, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35121569

RESUMEN

OBJECTIVES: This study aimed to examine the changes in depression and anxiety symptoms among Brazilian adults over 10 months of the COVID-19 pandemic. STUDY DESIGN/METHODS: The present study used data from wave 1 (June/July 2020) and wave 2 (December 2020/January 2021) of the Prospective Study About Mental and Physical Health (PAMPA) Cohort, a state-level, ambispective longitudinal study with adults from southern Brazil. The frequency of anxiety and depressive symptoms was assessed using the Hospital Anxiety and Depression Scale. Anxiety and depressive symptoms before social distancing were retrospectively assessed during wave 1. RESULTS: Most of the 674 participants were classified as non-symptomatic for depressive (85.0%) and anxiety symptoms (73.2%) before the COVID-19 pandemic. At wave 1, there were increases in symptoms of depression (7.6% [95% confidence interval [CI]: 7.2%, 8.1%]) and anxiety (9.1% [95% CI: 8.6%, 9.5%]). These decreased at wave 2 (depression: 6.9% [95% CI: 6.5%, 7.2%]; anxiety: 7.4% [95% CI: 7.1%, 7.8%]) although they were still elevated compared with pre-COVID (depression: 4.5% [95% CI: 4.2%, 4.8%]; anxiety: 5.8% [95% CI: 5.5%, 6.1%]). Adults living alone (b = 0.44 [95% CI: 0.07, 0.82]) had a faster trajectory in anxiety symptoms than their counterparts. Cohort members who were living alone (b = 0.24 [95% CI: 0.06, 0.42]) and with diagnosed chronic disease (0.32 [95% CI: 0.18, 0.46]) had a faster increase in depressive symptoms than their respective counterparts. Participants aged ≥60 years showed a slower trajectory of depressive (b = -0.46 [95% CI: -0.73, -0.18]) and anxiety (b = -0.61 [95% CI: -1.20, -0.02) symptoms. CONCLUSIONS: During 10 months of COVID-19, anxiety and depression symptoms improved but were still higher than before COVID-19.


Asunto(s)
COVID-19 , Adulto , Ansiedad/epidemiología , Brasil/epidemiología , COVID-19/epidemiología , Depresión/epidemiología , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Pandemias , Estudios Prospectivos , Estudios Retrospectivos , SARS-CoV-2
10.
Chemistry ; 27(58): 14370-14389, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34363268

RESUMEN

Lanthanide complexes have attracted a widespread attention due to their structural diversity, as well as multifunctional and tunable properties. The development of lanthanide based functional materials has often relied on the design of the secondary coordination sphere of the corresponding lanthanide complexes. For instance, usually simple lanthanide salts (solvento complexes) do not catalyze effectively organic reactions or provide low yield of the expected product, whereas the presence of a suitable organic ligand with a noncovalent bond donor or acceptor centre (secondary coordination sphere) modifies the symmetry around the metal centre in lanthanide complexes which then successfully can act as catalysts in both homogenous and heterogenous catalysis. In this minireview, we discuss several relevant examples, based on X-ray crystal structure analyses, in which the hydrogen, halogen, chalcogen, pnictogen, tetrel and rare-earth bonds, as well as cation-π, anion-π, lone pair-π, π-π and pancake interactions, are used as a synthon in the decoration of the secondary coordination sphere of lanthanide complexes.

11.
J Phys Chem A ; 125(17): 3696-3709, 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33890788

RESUMEN

The thermodynamic properties and band gap energies were evaluated for six ortho- and peri-fused polycyclic aromatic hydrocarbons (PAHs): triphenylene; benzo[a]pyrene; benzo[e]pyrene; perylene; benzo[ghi]perylene; coronene. The standard molar enthalpies of formation in the crystalline state and the standard molar enthalpies of sublimation were measured by high precision combustion calorimetry and Knudsen effusion methodology, respectively. The combination of the molar enthalpies of formation in the crystalline state with the respective enthalpies of sublimation was used to evaluate the energetics of the progressive peri-fusion of the aromatic moieties from triphenylene to coronene aiming to investigate the hypothetical superaromaticity character of coronene. The linear trend of the enthalpy of formation in crystalline and gaseous phases in the series (from benzo[e]pyrene to coronene) is an irrefutable indication of a non-superaromaticity character of coronene. High accurate thermodynamic properties of sublimation (volatility, enthalpy, and entropy of sublimation) were derived by the measurement of vapor pressures as a function of temperature, using a Knudsen/quartz crystal effusion methodology. Furthermore, the π-electronic conjugation of these compounds was explored by evaluation of the optical band gaps along with this series of compounds. The morphology of perylene, benzo[ghi]perylene, and coronene thin films, deposited by physical vapor deposition onto transparent conductive oxide substrates (ITO and FTO), was used to analyze the nucleation and growth mechanisms. The morphologies observed were found to be related to the cohesive energy and entropy of the bulk.

12.
Public Health ; 190: 101-107, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33387848

RESUMEN

OBJECTIVES: We aimed to compare the prevalence of depression and anxiety symptoms before and during the pandemic and identify factors associated with aggravated mental health symptoms. STUDY DESIGN: Retrospective cohort study. METHODS: We identified the proportion of normal, mild, moderate, and severe symptoms of depression and anxiety before and during the social distancing restrictions in adults from southern Brazil. An online, self-administered questionnaire was delivered for residents within the state of Rio Grande do Sul. Depressive and anxiety symptoms were examined by the Hospital Anxiety and Depression Scale. RESULTS: Most of the participants (n = 2314) aged between 31 and 59 years (54.2%), were women (76.6%), White (90.6%) with a university degree (66.6%). Moderate-to-severe symptoms of depression and anxiety were reported in 3.9% and 4.5% of participants, respectively, before COVID-19. During the pandemic (June-July, 2020), these proportions increased to 29.1% (6.6-fold increase) and 37.8% (7.4-fold increase), respectively. Higher rates of depressive and anxiety symptoms were observed among women, those aged 18-30 years, diagnosed with chronic disease and participants who had their income negatively affected by social restrictions. Remaining active or becoming physically active during social distancing restrictions reduced the probability of aggravated mental health disorders. CONCLUSIONS: Depressive and anxiety symptoms had a 6.6- and 7.4-fold increase since the COVID-19 pandemic. Public policies such as physical activity promotion and strategies to reduce the economic strain caused by this pandemic are urgently needed to mitigate the impact of the pandemic on mental health.


Asunto(s)
Ansiedad/epidemiología , COVID-19/psicología , Depresión/epidemiología , Salud Mental/estadística & datos numéricos , SARS-CoV-2 , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/etiología , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Brasil/epidemiología , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/prevención & control , Estudios de Cohortes , Depresión/etiología , Femenino , Humanos , Renta , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pandemias , Prevalencia , Estudios Retrospectivos , Encuestas y Cuestionarios , Adulto Joven
13.
Public Health ; 200: 49-55, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34673460

RESUMEN

OBJECTIVES: This study aimed to identify the effects of different physical activities practised during the time period when COVID-19 social distancing measures were in place on the risk of subjective memory decline in adults. STUDY DESIGN: Retrospective cohort study. METHODS: Data from the Prospective Study about Mental and Physical Health (PAMPA), a state-level (Rio Grande do Sul, Brazil), online-based cohort study, were analysed. Respondents were asked to rate their memory before COVID-19 social distancing measures were implemented (retrospectively) and on the day that the survey was completed. Subjective memory decline was defined as a perceived worsening of memory function during COVID-19 social distancing compared with the pre-pandemic period. The types of physical activity practised before and during COVID-19 social distancing measures were assessed. RESULTS: Data from 2319 adults were included. Out-of-home endurance, muscle strengthening, combined endurance and muscle strengthening, and stretching activities reduced the risk of subjective memory decline during the pandemic. In terms of physical activities practised at home, only muscle strengthening did not protect against subjective memory decline. Participants who sustained any type of physical activity at home during the COVID-19 pandemic showed a reduced risk for subjective memory decline. CONCLUSIONS: Physical activity, regardless of the type of activity and location performed, during the time period when COVID-19 social distancing measures were in place can mitigate the effects of the pandemic on subjective memory decline.


Asunto(s)
COVID-19 , Pandemias , Adulto , Estudios de Cohortes , Ejercicio Físico , Humanos , Trastornos de la Memoria , Estudios Prospectivos , Estudios Retrospectivos , SARS-CoV-2
14.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669746

RESUMEN

The new coordination polymers (CPs) [Zn(µ-1κO1:1κO2-L)(H2O)2]n·n(H2O) (1) and [Cd(µ4-1κO1O2:2κN:3,4κO3-L)(H2O)]n·n(H2O) (2) are reported, being prepared by the solvothermal reactions of 5-{(pyren-4-ylmethyl)amino}isophthalic acid (H2L) with Zn(NO3)2.6H2O or Cd(NO3)2.4H2O, respectively. They were synthesized in a basic ethanolic medium or a DMF:H2O mixture, respectively. These compounds were characterized by single-crystal X-ray diffraction, FTIR spectroscopy, thermogravimetric and elemental analysis. The single-crystal X-ray diffraction analysis revealed that compound 1 is a one dimensional linear coordination polymer, whereas 2 presents a two dimensional network. In both compounds, the coordinating ligand (L2-) is twisted due to the rotation of the pyrene ring around the CH2-NH bond. In compound 1, the Zn(II) metal ion has a tetrahedral geometry, whereas, in 2, the dinuclear [Cd2(COO)2] moiety acts as a secondary building unit and the Cd(II) ion possesses a distorted octahedral geometry. Recently, several CPs have been explored for the cyanosilylation reaction under conventional conditions, but microwave-assisted cyanosilylation of aldehydes catalyzed by CPs has not yet been well studied. Thus, we have tested the solvent-free microwave-assisted cyanosilylation reactions of different aldehydes, with trimethylsilyl cyanide, using our synthesized compounds, which behave as highly active heterogeneous catalysts. The coordination polymer 1 is more effective than 2, conceivably due to the higher Lewis acidity of the Zn(II) than the Cd(II) center and to a higher accessibility of the metal centers in the former framework. We have also checked the heterogeneity and recyclability of these coordination polymers, showing that they remain active at least after four recyclings.


Asunto(s)
Aldehídos/química , Cianuros/química , Microondas , Polímeros/química , Pirenos/química , Compuestos de Trimetilsililo/química , Catálisis , Enlace de Hidrógeno , Ligandos , Modelos Moleculares , Conformación Molecular , Polímeros/síntesis química , Solventes , Termogravimetría
15.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670480

RESUMEN

One-pot reaction of the Schiff base N,N'-ethylene bis(salicylaldimine) (H2L), CoCl2.6H2O, and [Ph2SnCl2] in acetone produces the mixed valence CoIICoIII2 compound [CoIICoIII2(µ-L)2(Ph)2(µ-Cl)2]·(CH3)2CO·H2O (1). Our recent study already revealed that the same reaction mixtures in methanol or ethanol produced a heterometallic SnIVCoIII (2) or monometallic CoIII complex (3), respectively. Comparison of these organometallic systems shows that the 2,1-intermetallic Ph shift occurs in any of those solvents, but their relevant structural features (mononuclear, dinuclear-heterometallic, and trinuclear mixed valence) are solvent dependent. Geometrical structural rotation is also discussed among the related organometallic CoIICoIII2 systems. The AC magnetic susceptibility measurements indicate that 1 is a single molecule magnet (SMM), exhibiting a field-induced slow magnetic relaxation with two modes. The relaxation time for the low-frequency channel is as slow as τ~0.6 s at T = 2.0 K and BDC = 1.0 T.


Asunto(s)
Cobalto/química , Imanes/química , Solventes/química , Cristalografía por Rayos X , Electricidad , Campos Magnéticos , Conformación Molecular , Rotación , Temperatura
16.
Microb Pathog ; 144: 104127, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32169485

RESUMEN

Despite the main strategy to overcome bacterial resistance has focused on the development of more potent antimicrobial agents, the evolutionary pressure caused by such drugs makes this strategy limited. Molecules that interfere with virulence factors appear as a promising alternative though, as they cause reduced selective pressure. As a matter of fact, staphyloxanthin biosynthesis inhibition (STXBI) has been pursued as promising strategy to reduce S. aureus virulence. Herein, we report the inhibitory profile of 27 tetrangomycin derivatives over staphyloxanthin production. The experimental result showed that naphthoquinone dehydro-α-lapachone (25 - EC50 = 57.29 ± 1.15 µM) and 2-Isopropylnaphtho[2,3-b]furan-4,9-dione (26 EC50 = 82.10 ± 1.09 µM) are the most potent compounds and suggest that hydrogen acceptor groups and lipophilic moieties decorating the naphthoquinone ring are crucial for STXBI. In addition, we present an in situ analysis, through RAMAN spectroscopy, that is inexpensive and might be employed to probe the mechanism of action of staphyloxanthin biosynthesis inhibitors. Therefore, our molecular simplification strategies afforded promising lead compounds for the development of drugs that modulate S. aureus staphyloxanthin biosynthesis.


Asunto(s)
Antibacterianos/farmacología , Naftoquinonas/farmacología , Staphylococcus aureus/metabolismo , Xantófilas/metabolismo , Benzo(a)Antracenos/química , Benzo(a)Antracenos/farmacología , Farmacorresistencia Bacteriana Múltiple , Naftalenos/química , Naftalenos/farmacología , Naftoquinonas/química , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Factores de Virulencia/antagonistas & inhibidores , Factores de Virulencia/biosíntesis
17.
Diabet Med ; 37(11): 1866-1873, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32542873

RESUMEN

AIM: To examine the association between antidepressant medication use and the risk of type 2 diabetes. METHODS: Data were obtained from the E3N study (Étude Épidémiologique de Femmes de la Mutuelle Générale de l'Éducation Nationale), a French cohort study initiated in 1990, with questionnaire-based follow-up every 2 or 3 years. Exposure to antidepressants was obtained from drug reimbursement files available from 2004 onwards, and individually matched with questionnaire data. Cases of type 2 diabetes were identified from drug reimbursements. Cox proportional-hazard regression models were used, with drug exposure considered as a time-varying parameter. RESULTS: Of the 63 999 women who were free of drug-treated type 2 diabetes at baseline in 2005, 1124 developed type 2 diabetes over the 6-year follow-up. Current use of antidepressants was associated with an increased risk of type 2 diabetes [hazard ratio 1.34 (95% CI 1.12, 1.61)] compared to non-users. When the different types of antidepressants were considered, women who currently used selective serotonin reuptake inhibitors, imipramine-type, 'other' or 'mixed' antidepressants had a 1.25-fold (95% CI 0.99, 1.57), 1.66-fold (95% CI 1.12, 2.46), 1.35-fold (95% CI 1.00, 1.84) and 1.82-fold (95% CI 0.85, 3.86) increase in risk of type 2 diabetes compared to non-users, respectively. CONCLUSION: Our study suggests a positive association between antidepressant use and the risk of type 2 diabetes among women. If this association is confirmed, screening and surveillance of glucose levels should be considered in the context of antidepressant therapy. Further studies assessing the underlying mechanisms of this association are needed. (ClinicalTrials.gov identifier: NCT03285230).


Asunto(s)
Antidepresivos/uso terapéutico , Diabetes Mellitus Tipo 2/epidemiología , Anciano , Estudios de Cohortes , Femenino , Francia/epidemiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo
18.
Inorg Chem ; 59(22): 16301-16318, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33100004

RESUMEN

The new 2D coordination polymers (CPs) [M(L)2(H2O)2]n [M = CoII (1) and NiII (2); L = 4-(pyridin-3-ylcarbamoyl)benzoate] were synthesized from pyridyl amide-functionalized benzoic acid (HL). They were characterized by elemental, Fourier transform infrared, thermogravimetric, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (XRD) structural analyses. Single-crystal XRD analysis revealed the presence of a 2D polymeric architecture, and topological analyses disclose a 2,4-connected binodal net. A thermochromic effect leads to the production of two new CPs, 1' and 2', by heating at ca. 220 °C, accompanied by a color change from orange to purple in the case of 1 and from blue to green in the case of 2. The transformation of 1 to 1' takes place through an intermediate (1a) with a different twist of the L- ligand, leading to the formation of a 1D polymeric architecture, as proven by single-crystal XRD analysis. The addition of water or keeping 1' or 2' in air for several days leads to regeneration of 1 or 2, respectively. The thermochromic-triggered structural transformations of 1 and 2 were further substantiated by PXRD and UV-vis ground-state diffuse-reflectance absorption studies. The supercapacitance ability of the CPs 1 and 2 and a Ni-Co composite (made from mixing the CPs 1 and 2) was investigated by electroanalytical techniques, such as cyclic voltammetry and electrochemical impedance spectroscopy. The CP 2 exhibits the highest specific capacity of 273.8 C g-1 at an applied current density of 1.5 A g-1. These newly developed CPs further act as electrocatalysts for the water-splitting reaction.

19.
Phys Chem Chem Phys ; 22(26): 15022-15034, 2020 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-32597431

RESUMEN

Photonic and electronic properties exist inherently in ferroelectric barium titanate (BaTiO3); severe luminescence quenching also exists due to the insufficient confinement of excitons. In this sense, high optical emission can only be achieved by its chemical and structural modification. Thin BaTiO3 and Er:BaTiO3 films were grown by the spin coating method on a glass substrate at room temperature. Self-trapping of excitons in the thin BaTiO3 film and its structural modification due to the doping with Er3+ ions (Er:BaTiO3) are verified using scanning confocal fluorescence microscopy (SCFM), where self-trapping excitons never occured in its pure state. By thermal treatment and doping (BaTiO3 and Er:BaTiO3) we obtained localization of the excitons, which would further induce lattice strain around the surface defects, to accommodate the self-trapped excitons. With such a self-trapped state, the structure of BaTiO3 generates broadband emission of several overlapping bands between 1.95 and 2.65 eV at room temperature, while the structure Er:BaTiO3 showed defined emission bands at 2.24 and 2.35 eV, with very weak contributions of the emission due to the self-trapping state. The influence of the variation of the excitation wavelength using 1PE and 2PE on the emission bands of BaTiO3 and Er:BaTiO3 is also investigated. The results of enhanced emission bands suggest a clear dependence of the emission intensity on the excitation energy, where a ∼3 fold enhancement in emission has been demonstrated under Er3+ (1.55 eV) excitation, which can be attributed to effective energy transfer between the Er3+ ions. As a result, it is concluded that the developed BaTiO3 and Er:BaTiO3 can pave the way for future photonic devices.

20.
J Nat Prod ; 83(5): 1409-1415, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32372647

RESUMEN

Citrus sinensis and Citrus limonia were obtained by germination from seeds, and isotopic-labeling experiments using d-[1-13C]glucose were performed with the seedlings. After 60 days, the seedlings were analyzed by high-performance liquid chromatography-ultraviolet-solid-phase extraction-nuclear magnetic resonance, data and the 13C enrichment patterns of xanthyletin and seselin indicated that the pyran ring was formed by the methylerythritol phosphate pathway and that the coumarin moiety was derived from the shikimate pathway in both compounds. This information regarding the biosynthetic pathway can be used to increase resistance against phytopathogens, because xanthyletin and seselin are reported to have antimicrobial activity on the growth of Xylella fastidiosa, which causes citrus variegated chlorosis in orange.


Asunto(s)
Marcaje Isotópico/métodos , Piranocumarinas/metabolismo , Isótopos de Carbono , Cromatografía Líquida de Alta Presión , Citrus/metabolismo , Citrus sinensis/metabolismo , Espectroscopía de Resonancia Magnética , Estructura Molecular , Enfermedades de las Plantas/microbiología , Piranocumarinas/química , Piranocumarinas/aislamiento & purificación , Ácido Shikímico/metabolismo , Extracción en Fase Sólida , Espectrofotometría Ultravioleta , Xylella/efectos de los fármacos
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