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1.
BMC Public Health ; 24(1): 735, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454363

RESUMO

BACKGROUND: In the last decade, interest in working life expectancy (WLE) and socioeconomic differences in WLE has grown considerably. However, a comprehensive overview of the socioeconomic differences in WLE is lacking. The aim of this review is to systematically map the research literature to improve the insight on differences in WLE and healthy WLE (HWLE) by education, occupational class and income while using different ways of measuring and estimating WLE and to define future research needs. METHODS: A systematic search was carried out in Web of Science, PubMed and EMBASE and complemented by relevant publications derived through screening of reference lists of the identified publications and expert knowledge. Reports on differences in WLE or HWLE by education, occupational class or income, published until November 2022, were included. Information on socioeconomic differences in WLE and HWLE was synthesized in absolute and relative terms. RESULTS: A total of 26 reports from 21 studies on educational and occupational class differences in WLE or HWLE were included. No reports on income differences were found. On average, WLE in persons with low education is 30% (men) and 27% (women) shorter than in those with high education. The corresponding numbers for occupational class difference were 21% (men) and 27% (women). Low-educated persons were expected to lose more working years due to unemployment and disability retirement than high-educated persons. CONCLUSIONS: The identified socioeconomic inequalities are highly relevant for policy makers and pose serious challenges for equitable pension policies. Many policy interventions aimed at increasing the length of working life follow a one-size-fits-all approach which does not take these inequalities into account. More research is needed on socioeconomic differences in HWLE and potential influences of income on working life duration.


Assuntos
Pessoas com Deficiência , Expectativa de Vida , Masculino , Humanos , Feminino , Aposentadoria , Desemprego , Pensões , Fatores Socioeconômicos
2.
Inorg Chem ; 62(27): 10548-10558, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37377140

RESUMO

A series of four new Dy12 dodecanuclear clusters based on azobenzene derivative ligands of salicylic acid (L1-L4) has been synthesized and characterized in the crystalline phase using X-ray diffraction on single crystal and powder, IR spectroscopy, elemental analysis, and DSC-TGA methods. It was revealed that all obtained clusters exhibit the formation of the similar metallic cluster nodes, as vertex-sharing heterocubanes, obtained from four Dy3+ cations, three bridging hydroxyl groups, and O atoms from the salicylic ligands. The coordination geometry around the Dy(III) centers has been carefully analyzed. Whereas Dy12-L1 and Dy12-L2 with L1 and L2 containing Me and OMe groups in para positions of the phenyl rings, respectively, form similar porous 3D diamond-like molecular networks due to CH-π interactions, for Dy12-L3 with L3 bearing NO2-electron-withdrawing group, the generation of 2D molecular grids assembled by π-π staking is observed, and for Dy12-L4 with L4 bearing phenyl substituent, 3D hexagonal channels have been generated. The complexes Dy12-L1, Dy12-L2, and Dy12-L3 exhibit a zero-field slow magnetic relaxation effect. After UV irradiation of Dy12-L1, a decrease of the magnetic anisotropy energy barrier displaying the possibility of control over magnetic properties by the external stimulus has been observed.

3.
Bioorg Chem ; 139: 106742, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37480816

RESUMO

Tumor selectivity is yet a challenge in chemotherapy-based cancer treatment. A series of calixarenes derivatized at the lower rim with 3-phenyl-1H-pyrazole units with variable upper-rim substituent and conformations of macrocyclic core, alkyl chain length between heterocycle and core, as well as phenolic monomer (5-(4-tert-butylphenyloxy)methoxy-3-phenyl-1H-pyrazole) have been synthesized and characterized in a range of therapeutically relevant cellular models (M-HeLa, MCF7, A-549, PC3, Chang liver, and Wi38) from different target organs/systems. Specific cytotoxicity for M-HeLa cells has been observed in tert-butylcalix[4]arene pyrazoles in 1,3-alternate (compound 7b) and partial cone (compound 7c) conformations with low mutagenicity and haemotoxicity and in vivo toxicity in mice. Compounds 7b,c have induced mitochondrial pathway of apoptosis of M-HeLa cells through caspase-9 activation preceded by the cell cycle arrest at G0/G1 phase. A concomitant overexpression of DNA damage markers in pyrazole-treated M-HeLa cells suggests that calixarene pyrazoles target DNA, which was supported by the presence of interactions between calixarenes and ctDNA at the air-water interface.


Assuntos
Calixarenos , Neoplasias , Poríferos , Humanos , Animais , Camundongos , Calixarenos/farmacologia , Células HeLa , Pirazóis/farmacologia , Neoplasias/tratamento farmacológico
4.
Int Arch Occup Environ Health ; 96(1): 93-104, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35857111

RESUMO

OBJECTIVE: Depressive and anxiety disorders are prevalent among employees in general. Still, knowledge regarding the contribution of these disorders to the dynamics of the labor market in terms of working time, sickness absence, and unemployment is scarce. We aim to quantify the linkage of depressive and anxiety disorders with labor market participation using the expected labor market affiliation method (ELMA), in a large sample of Danish employees. METHODS: We combined three survey waves on occupational health with six high-quality national registers in N = 43,148 Danish employees, of which the 2012 survey contributed 29,665 person years, the 2014 survey 33,043 person years, and the 2016 survey 35,375 person years. We used the new ELMA method to estimate the multi-state transition probabilities and 2-year expected time in work, sickness absence, and unemployment. Depressive and anxiety disorders were assessed by the Major Depression Inventory and the SCL-ANX4 scales, respectively. We adjusted for multiple variables by applying inverse probability weighting in groups of gender and age. RESULTS: Depressive and anxiety disorders among employees link to reduced labor market affiliation by significantly changed transitions probabilities between the labor markets states, viewed as reduced working time by 4-51 days (in two years), increased time in sickness absence by 6-44 days (in two years), and unemployment by 6-12 days (in two years) when compared to employees without depression or anxiety disorders. The results were most pronounced for women employees and for employees with both depression and anxiety disorders. CONCLUSIONS: The study reveals detailed insight into what extent depression and anxiety disorders influence the labor market affiliation, in terms of the complex interrelation between working time, sickness absence, and unemployment. The study emphasizes the importance of preventing and handling depressive and anxiety disorders among employees for strengthening work participation.


Assuntos
Ocupações , Desemprego , Humanos , Feminino , Estudos Longitudinais , Transtornos de Ansiedade/epidemiologia , Dinamarca/epidemiologia , Licença Médica
5.
Eur J Public Health ; 33(6): 1071-1079, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-37634088

RESUMO

BACKGROUND: Reduced work ability is relatively common among job seekers and it can hinder future labour market attachment. A commonly used measure to increase employability is the use of active labour market programmes. While vocational labour market training (LMT) has been shown to be an effective way to increase work participation among job seekers, there is still uncertainty about how LMT works in different population groups, for example, among persons with a work disability history. METHODS: We used nationally representative Finnish register data on 16 062 LMT participants in 2008-2015 aged 25-59 with a history of sickness absence (SA) and propensity score matched participants without such history. For matching, we used information on sociodemographic and work-related factors. We used difference-in-differences analysis to investigate the differential changes in work participation before and after LMT between those with and those without SA history. RESULTS: Having a history of SA was associated with a lower gain in work participation after LMT, but the magnitude varied by sex, employment history and follow-up time. In women, having a history of SA contributed to 3.9-6.2 percentage points smaller increase in work participation 1-3 years after LMT, depending on the employment history. In men, the corresponding numbers were 2.0-4.3 percentage points. The results were more pronounced if the SA was due to mental disorders. CONCLUSIONS: The results indicate that work disability, especially due to mental disorders, can hamper work participation after LMT and should be considered when planning employment-enhancing measures for job seekers.


Assuntos
Pessoas com Deficiência , Transtornos Mentais , Masculino , Humanos , Feminino , Pontuação de Propensão , Emprego , Transtornos Mentais/epidemiologia , Ocupações
6.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068985

RESUMO

This work focuses on the synthesis of a new series of amphiphilic derivatives of calix[4]arenes for the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The aggregation properties of synthesized calix[4]arenes were studied using various techniques (fluorescence spectroscopy, nanoparticle tracking analysis, and dynamic light scattering). Increasing the length of the alkyl substituent led to stronger hydrophobic interactions, which increased polydispersity in solution. The zwitterionic nature of the synthesized calix[4]arenes was established using different types of dyes (Eosin Y for anionic structures and Rhodamine 6G for cationic structures). The synthesized calix[4]arenes were used as organic stabilizers for CuI. The catalytic efficiency of CuI-calix[4]arene was compared with that of the phase transfer catalyst tetrabutylammonium bromide (TBAB) and the surfactant sodium dodecyl sulfate (SDS). For all calixarenes, the selectivity in the CuAAC reaction was higher than that observed when TBAB and SDS were estimated.


Assuntos
Azidas , Calixarenos , Azidas/química , Cátions , Difusão Dinâmica da Luz , Micelas , Catálise , Calixarenos/química
7.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36768407

RESUMO

A series of new 2-hydroxy-3-methoxybenzylidenethiazolo[3,2-a]pyrimidines with different aryl substituents at the 5 position are synthesized and characterized by 1H/ 13C NMR and IR-spectroscopy and mass-spectrometry, as well as single crystal X-ray diffraction (SCXRD). It was demonstrated that the type of hydrogen bonding can play a key role in the chiral discrimination of these compounds in the crystalline phase. The hydrogen bond of the O-H...N type leads to 1D supramolecular heterochiral chains or conglomerate crystallization in the case of the formation of homochiral chains. The hydrogen bond of O-H...O type gave racemic dimers, which are packed into 2D supramolecular layers with a parallel or angular dimers arrangement. Halogen bonding of the N...Br or O...Br type brings a new motif into supramolecular self-assembly in the crystalline phase: the formation of 1D supramolecular homochiral chains instead 2D supramolecular layers. The study of cytotoxicity against various tumor cells in vitro was carried out. It was found that 2-hydroxy-3-methoxybenzylidenethiazolo[3,2-a]pyrimidines with 3-nitrophenyl substituent at C5 carbon atom demonstrated a high efficiency against M-HeLa (cervical adenocarcinoma) and low cytotoxicity against normal liver cells.


Assuntos
Antineoplásicos , Pirimidinas , Pirimidinas/farmacologia , Pirimidinas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética
8.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677529

RESUMO

Hypoxia accompanies many human diseases and is an indicator of tumor aggressiveness. Therefore, measuring hypoxia in vivo is clinically important. Recently, complexes of calix[4]arene were identified as potent hypoxia markers. The subject of this paper is new hypoxia-sensitive host-guest complexes of thiacalix[4]arene. We report a new high-yield synthesis method for thiacalix[4]arene with four anionic carboxyl azo fragments on the upper rim (thiacalixarene L) and an assessment of the complexes of thiacalixarene L with the most widespread cationic rhodamine dyes (6G, B, and 123) sensitivity to hypoxia. Moreover, 1D and 2D NMR spectroscopy data support the ability of the macrocycles to form complexes with dyes. Rhodamines B and 123 formed host-guest complexes of 1:1 stoichiometry. Complexes of mixed composition were formed with rhodamine 6G. The association constant between thiacalixarene L and rhodamine 6G is higher than for other dyes. Thiacalixarene L-dye complexes with rhodamine 6G and rhodamine B are stable in the presence of various substances present in a biological environment. The UV-VIS spectrometry and fluorescence showed hypoxia responsiveness of the complexes. Our results demonstrate that thiacalixarene L has a stronger binding with dyes compared with the previously reported azo-calix[4]arene carboxylic derivative. Thus, these results suggest higher selective visualization of hypoxia for the complexes with thiacalixarene L.

9.
Int J Mol Sci ; 23(4)2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35216456

RESUMO

Sulfur-containing groups preorganized on macrocyclic scaffolds are well suited for liquid-phase complexation of soft metal ions; however, their binding potential was not extensively studied at the air-water interface, and the effect of thioether topology on metal ion binding mechanisms under various conditions was not considered. Herein, we report the interface receptor characteristics of topologically varied thiacalixarene thioethers (linear bis-(methylthio)ethoxy derivative L2, O2S2-thiacrown-ether L3, and O2S2-bridged thiacalixtube L4). The study was conducted in bulk liquid phase and Langmuir monolayers. For all compounds, the highest liquid-phase extraction selectivity was revealed for Ag+ and Hg2+ ions vs. other soft metal ions. In thioether L2 and thiacalixtube L4, metal ion binding was evidenced by a blue shift of the band at 303 nm (for Ag+ species) and the appearance of ligand-to-metal charge transfer bands at 330-340 nm (for Hg2+ species). Theoretical calculations for thioether L2 and its Ag and Hg complexes are consistent with experimental data of UV/Vis, nuclear magnetic resonance (NMR) spectroscopy, and single-crystal X-ray diffractometry of Ag-thioether L2 complexes and Hg-thiacalixtube L4 complex for the case of coordination around the metal center involving two alkyl sulfide groups (Hg2+) or sulfur atoms on the lower rim and bridging unit (Ag+). In thiacrown L3, Ag and Hg binding by alkyl sulfide groups was suggested from changes in NMR spectra upon the addition of corresponding salts. In spite of the low ability of the thioethers to form stable Langmuir monolayers on deionized water, one might argue that the monolayers significantly expand in the presence of Hg salts in the water subphase. Hg2+ ion uptake by the Langmuir-Blodgett (LB) films of ligand L3 was proved by X-ray photoelectron spectroscopy (XPS). Together, these results demonstrate the potential of sulfide groups on the calixarene platform as receptor unit towards Hg2+ ions, which could be useful in the development of Hg2+-selective water purification systems or thin-film sensor devices.


Assuntos
Espaços Confinados , Mercúrio , Ligantes , Mercúrio/química , Metais/química , Sais , Sulfetos/química , Enxofre , Água/química
10.
Int J Mol Sci ; 23(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36499212

RESUMO

Artificial gene delivery systems are in great demand from both scientific and practical biomedical points of view. In this paper, we present the synthesis of a new click chemistry calix[4]arene precursor with free lower rim and new water-soluble calixarene triazoles with 12 amino-groups on the upper rim (one with free phenol hydroxyl groups and two another containing four butyl or tetradecyl fragments). Aggregation in the series of amino-triazole calixarenes of different lipophilicity (calixarene with free phenol hydroxyl groups or butyl and tetradecyl fragments on the lower rim) was studied using dynamic light scattering and fluorescent pyrene probe. It was found that calix[4]arene with a free lower rim, like alkyl-substituted butyl calix[4]arene, forms stable submicron aggregates 150-200 nm in size, while the more lipophilic tetradecyl -substituted calix[4]arene forms micellar aggregates19 nm in size. Using UV-Vis spectroscopy, fluorimetry and CD, it was shown that amino-triazole calix[4]arenes bind to calf thymus DNA by classical intercalation. According to DLS and TEM data, all studied macrocycles cause significant DNA compaction, forming stable nanoparticles 50-20 nm in size. Among all studied calix[4]arenes the most lipophilic tetradecyl one proved to be the best for both binding and compaction of DNA.


Assuntos
Calixarenos , Triazóis , Poliaminas , Fenol , Calixarenos/química , DNA
11.
Molecules ; 28(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36615457

RESUMO

Fluorescent derivatives attract the attention of researchers for their use as sensors, photocatalysts and for the creation of functional materials. In order to create amphiphilic fluorescent derivatives of calixarenes, a fluorescein derivative containing oligoethylene glycol and propargyl groups was obtained. The resulting fluorescein derivative was introduced into three different (thia)calix[4]arene azide derivatives. For all synthesized compounds, the luminescence quantum yields have been established in different solvents. Using UV-visible spectroscopy, dynamic light scattering, as well as transmission and confocal microscopy, aggregation of macrocycles was studied. It was evaluated that calixarene derivatives with alkyl substituents form spherical aggregates, while symmetrical tetrafluorescein-containing thiacalix[4]arene forms extended worm-like aggregates. The macrocycle containing tetradecyl fragments was found to be the most efficient in photoredox ipso-oxidation of phenylboronic acid. In addition, it was shown that in a number of different electron donors (NEt3, DABCO and iPr2EtN), the photoredox ipso-oxidation proceeds best with triethylamine. It has been shown that a low molecular weight surfactant Triton-X100 can also improve the photocatalytic abilities of an oligoethylene glycol fluorescein derivative, thus showing the importance of a combination of micellar and photoredox catalysis.


Assuntos
Calixarenos , Água , Água/química , Fenóis/química , Calixarenos/química , Catálise , Fluoresceínas
12.
Molecules ; 27(8)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35458633

RESUMO

New fluorescent systems for photocatalysis, sensors, labeling, etc., are in great demand. Amphiphilic ones are of special interest since they can form functional colloidal systems that can be used in aqueous solutions. A new macrocycle platform for click chemistry and its adduct with o-propargylfluoresceine was synthesized and characterized using modern physical techniques. Nanosized solid lipid nanoparticles (SLNs) from the calixarene-fluoresceine adduct were synthesized through the solvent injection technique and well-characterized in the solution and in solid state using light-scattering and microscopy methods. The maximum fluorescence intensity of the SLNs was found to be in the pH range from 7 to 10. The Förster resonance energy transfer (FRET) efficiency from SLNs to rhodamine 6g was found to be 97.8%. Finally, pure SLNs and the FRET system SLNs-Rh6G were tested in model photocatalytic ipso oxidative hydroxylation of phenylboronic acid under blue LED light. The SLNs-Rh6G system was found to be the best, giving an almost qualitative phenol yield, which was shown by HPLC-UV analysis.


Assuntos
Lipídeos , Nanopartículas , Calixarenos , Portadores de Fármacos/química , Fluoresceína , Lipídeos/química , Lipossomos , Nanopartículas/química , Tamanho da Partícula , Fenóis
13.
Molecules ; 27(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36431842

RESUMO

A series of new thiazolo[3,2-a]pyrimidines different by aryl substituents in 2 and 5 positions are synthesized and characterized in solution as well as in the crystalline phase using 1H and 13C NMR-, IR-spectroscopies, mass-spectrometry methods, and single crystal X-ray diffraction (SCXRD). The SCXRD study revealed the role of intermolecular H-bonding in the formation of supramolecular architectures (racemic monomers, centrosymmetric racematic dimers, or homochiral 1D chains) of obtained thiazolo[3,2-a]pyrimidines derivatives depending on solvents (aprotic DMSO or protic EtOH) used upon the crystallization process. Moreover, the in vitro study of cytotoxicity toward different tumor cells showed their high or moderate efficiency with moderate cytotoxicity against normal liver cells which allows to consider the obtained thiazolo[3,2-a]pyrimidine derivatives as promising candidates for application as antitumor agents.


Assuntos
Antineoplásicos , Pirimidinas , Pirimidinas/química , Antineoplásicos/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética
14.
Molecules ; 27(16)2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-36014420

RESUMO

Elaboration of a convenient route towards donor-substituted pyrazoles from heteropropargyl precursors is challenging due to a number of thermodynamically favorable side reactions (e.g., acetylene-allene isomerization and Glaser homocoupling). In this work, Sonogashira cross-coupling conditions of 4-tert-butylphenyl propargyl ether with benzoyl chloride followed by tandem Michael addition/cyclocondensation with hydrazine into 3,5-disubstituted pyrazole (kinetic control), as well as cycloisomerization conditions of ketoacetylene intermediate into 2,5-disubstituted furan (thermodynamic control), were established through a variation of the catalyst loading, solvent polarity, excess of triethylamine, and time of reaction. During the optimization of process parameters, a number of by-products represented by a monophosphine binuclear complex (PPh3PdI2)2 with two bridging iodine atoms and diyne were identified and isolated in the pure form. The quantum-chemical calculations and solution-state 1H/13C NMR spectroscopy suggested that the 5(3)-(4-tert-butylphenyloxy)methoxy-3(5)-phenyl-1H-pyrazole exists in the tautomeric equilibrium in a polar methanol solvent and that individual tautomers could be characterized in case aprotic solvents employed. The pyrazole features a unique tetramer motif in the crystal phase formed by alternating 3(5)-phenyl-1H-pyrazole tautomers, which was stabilized by N-H···N bonds and stacking interactions of pyrazole rings, whereas pyrazole dimers were identified in the gas phase.


Assuntos
Furanos , Pirazóis , Pirazóis/química , Solventes , Termodinâmica
15.
Eat Weight Disord ; 27(5): 1585-1591, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35178680

RESUMO

PURPOSE: The concept of time perspective (TP) implies that a mental focus on past, present, or future affect a person makes decisions and take action. Inability to plan their life for a sufficiently long time perspective due to the COVID-19 pandemic appeared to have a pronounced impact on a human's lifestyle influencing their thoughts, feelings, and behaviors, including eating behavior. This study tested two hypotheses: (a) that during COVID-19 isolation, the incidence rate of food addiction is increased, and (b) people with present TP are more likely exhibited signs of food addiction (FA). METHODS: The final study sample included 949 people, mean age 21.8 ± 7.8 years (range: 17-71 years, women: 78.3%). Each participant indicated their personal data and completed Yale Food Addiction Scale and the Zimbardo Time Perspective Inventory. RESULTS: There was an increased incidence rate of FA (OR = 1.678, 95% CI = 1.324, 2.148, p = 0.000) during COVID-19 isolation. Individuals with balanced, future, and past positive TP were less likely to exhibit symptoms of FA. Persons with past negative, and present hedonistic TP were more likely to exhibit signs of FA. CONCLUSION: There was an increased incidence rate of FA during COVID-19 isolation. Persons with shortened time horizon are more likely to exhibit symptoms of FA. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.


Assuntos
COVID-19 , Dependência de Alimentos , Adolescente , Adulto , Estudos Transversais , Comportamento Alimentar , Feminino , Dependência de Alimentos/diagnóstico , Dependência de Alimentos/epidemiologia , Humanos , Pandemias , Inquéritos e Questionários , Adulto Jovem
16.
Public Health Nutr ; 24(18): 6027-6033, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34034842

RESUMO

OBJECTIVE: The purpose of this study was to analyse the relationships between food addiction (FA), anthropometric characteristics and academic performance. DESIGN: The average age (sd) of the participants was 17·5 (sd 2·7) years (64·1 % female). Each study participant indicated their sex, height, weight and academic performance and completed the Yale Food Addiction Scale. SETTING: Syktyvkar, Kirov, Tyumen, Yekaterinburg, Russia; Aizawl, India. PARTICIPANTS: The study involved 3426 people. RESULTS: FA was found in 8·7 % of participants from Russia and 14·6 % from India. In schoolchildren but not in university students, high academic performance was associated with a higher incidence rate of FA detection (OR = 1·16, 95 % CI 1·07, 1·26) and a lower BMI (OR = 0·72, 95 % CI 0·56, 0·94). CONCLUSIONS: These data showed an increased incidence rate of FA detection in adolescents with high academic performance.


Assuntos
Desempenho Acadêmico , Dependência de Alimentos , Adolescente , Antropometria , Criança , Feminino , Dependência de Alimentos/epidemiologia , Humanos , Índia , Masculino , Estudantes
17.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805474

RESUMO

Understanding the interaction of ions with organic receptors in confined space is of fundamental importance and could advance nanoelectronics and sensor design. In this work, metal ion complexation of conformationally varied thiacalix[4]monocrowns bearing lower-rim hydroxy (type I), dodecyloxy (type II), or methoxy (type III) fragments was evaluated. At the liquid-liquid interface, alkylated thiacalixcrowns-5(6) selectively extract alkali metal ions according to the induced-fit concept, whereas crown-4 receptors were ineffective due to distortion of the crown-ether cavity, as predicted by quantum-chemical calculations. In type-I ligands, alkali-metal ion extraction by the solvent-accessible crown-ether cavity was prevented, which resulted in competitive Ag+ extraction by sulfide bridges. Surprisingly, amphiphilic type-I/II conjugates moderately extracted other metal ions, which was attributed to calixarene aggregation in salt aqueous phase and supported by dynamic light scattering measurements. Cation-monolayer interactions at the air-water interface were monitored by surface pressure/potential measurements and UV/visible reflection-absorption spectroscopy. Topology-varied selectivity was evidenced, towards Sr2+ (crown-4), K+ (crown-5), and Ag+ (crown-6) in type-I receptors and Na+ (crown-4), Ca2+ (crown-5), and Cs+ (crown-6) in type-II receptors. Nuclear magnetic resonance and electronic absorption spectroscopy revealed exocyclic coordination in type-I ligands and cation-π interactions in type-II ligands.


Assuntos
Complexos de Coordenação/química , Éteres de Coroa/química , Íons/metabolismo , Fenóis/química , Sulfetos/química , Ar , Alquilação , Cálcio/metabolismo , Complexos de Coordenação/metabolismo , Éteres de Coroa/síntese química , Éteres de Coroa/metabolismo , Difusão Dinâmica da Luz , Íons/química , Extração Líquido-Líquido , Espectroscopia de Ressonância Magnética , Metais/química , Conformação Molecular , Fenóis/metabolismo , Solventes/química , Espectrofotometria Ultravioleta , Sulfetos/metabolismo , Água/química
18.
Molecules ; 26(22)2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34833956

RESUMO

A new polymeric NHC carrier was synthesized by sequential supramolecular self-assembly and copper-catalyzed azide-alkyne cycloaddition (CuAAC) of amphiphilic imidazolium calix[4]arenes with octyl lipophilic fragments. Obtained polytriazole-imidazolium particles were found as monodisperse submicron particles, with the average diameter of 236 ± 34 nm and average molecular weight of 1380 ± 96 kDa. Successful CuAAC polymerization has been proved using IR spectroscopy and high-resolution ESI mass spectrometry. Polymeric particles, as well as aggregates made from precursor macrocycles, were decorated by Pd clusters (2 nm) for further catalytic investigations. Pd nanoclusters, supported on the polymeric surface, were found highly catalytically active in the model reduction of p-nitrophenol, giving reaction rates an order of magnitude higher compared to literature examples. The reaction was recycled using the same catalyst five times without any loss of activity.

19.
Molecules ; 26(18)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34576922

RESUMO

A potential hypoxia-sensitive system host-guest complex of three calixarenes (including two with four anionic carboxyl and sulphonate azo fragments on the upper rim and a newly synthesized bis-azo adduct of calixarene in the cone configuration with azo fragments on the lower rim with the most widespread cationic and zwitterionic rhodamine dyes (123, 6G and B)) was studied using UV-VIS spectrometry and fluorescence as well as 1D and 2D NMR techniques. It was found that all three calixarenes form a complex with rhodamine dyes with a 1:1 composition. The association constants of calixarene-dye complexes with sulfonate calixarenes, especially in the case of tetra-anionic calixarene, turned out to be higher compared with carboxyl calixarene due to the more intense electrostatic interactions. For the first time using an HRESI MS technique, it was shown that the treatment of rhodamine 6G and 123 with sodium dithionite (SDT) produces a non-fluorescent leuco form of the dye, and only rhodamine B can be used with SDT without the occurrence of a side reduction. Moreover, it was identified that in addition to the reduction in the azo groups, SDT causes partial cleavage of the aryl ether bonds. The found features of SDT should be taken into account when SDT is used as an azoreductase mimic.

20.
Eat Weight Disord ; 26(7): 2333-2343, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33389716

RESUMO

PURPOSE: Food addiction (FA) is one of the causes of widespread obesity in modern society. It was shown that there is an age-associated increase in incidence rate of FA in adolescents/young adults. The purpose of this study was to analyze food preferences in schoolchildren and university students with FA. METHODS: High school and university students (N = 1607; age: 17.8 ± 2.7 years; girls: 77.0%) located in four settlements of Russia anonymously took part in the study. Study participants provided personal data (age, sex, height, and weight) and completed the Yale Food Addiction Scale, the Zung Self-Rating Depression Scale and the Munich ChronoType Questionnaire. In addition, they indicated food products with which they had problems. RESULTS: The frequency of detection of FA among university students was twice as high as among schoolchildren. University students with FA were 20.2% more likely than schoolchildren to report the symptom 'use continues despite knowledge of adverse consequences,' and 13.7% more likely to report the symptom 'tolerance.' Schoolchildren and university students with FA most often noted that foods high in sugar and fat were problematic. University students with FA also reported that foods with a high carbohydrate content were problematic. CONCLUSION: In university students with FA, in comparison with schoolchildren with FA, there is an increase in list of problematic food products, mainly due to products with a high carbohydrate content. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.


Assuntos
Dependência de Alimentos , Preferências Alimentares , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
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