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1.
J Mol Model ; 30(6): 183, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38782773

RESUMO

CONTEXT: The activation of C-H bonds is a fundamental process in synthetic organic chemistry, which enables their replacement by highly reactive functional groups. Coordination compounds serve as effective catalysts for this purpose, as they facilitate chemical transformations by interacting with C-H bonds. A comprehensive understanding of the mechanism of activation of this type of bond lays the foundation for the development of efficient protocols for cross-coupling reactions. We explored the activation of C(sp2)-H bonds in 1-Phenyl-4-vinyl-1H-1,2,3-triazole derivatives with CH3, OCH3, and NO2 substituents in the para position of the phenyl ring, using palladium acetate as catalyst. The studied reaction is the first step for subsequent conjugation of the triazoles with naphthoquinones in a Heck-type reaction to create a C-C bond. The basic nitrogen atoms of the 1,2,3-triazole coordinate preferentially with the cationic palladium center to form an activated species. A concerted proton transfer from the terminal vinyl carbon to one of the acetate ligands with low activation energy is the main step for the C(sp2)-H activation. This study offers significant mechanistic insights for enhancing the effectiveness of C(sp2)-H activation protocols in organic synthesis. METHODS: All calculations were performed using the Gaussian 09 software package and density functional theory (DFT). The structures of all reaction path components were fully optimized using the CAM-B3LYP functional with the Def2-SVP basis set. The optimized geometries were analyzed by computing the second-order Hessian matrix to confirm that the corresponding minimum or transition state was located. To account for solvent effects, the Polarizable Continuum Model of the Integral Equation Formalism (IEFPCM) with water as the solvent was used.

2.
J Mol Model ; 30(5): 145, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656715

RESUMO

CONTEXT: A complex supramolecular process involving electrostatic and dispersion interactions and asphaltene aggregation is associated with detrimental petroleum deposition and scaling that pose challenges to petroleum recovery, transportation, and upgrading. The homodimers of seven heterocyclic model compounds, representative of moieties commonly found in asphaltene structures, were studied: pyridine, thiophene, furan, isoquinoline, pyrazine, thiazole, and 1,3-oxazole. The contributions of hydrogen bonding involving water bridges spanning between dimers and π-π stacking to the total interaction energy were calculated and analyzed. The distance between the planes of the aromatic rings is correlated with the π-π stacking interaction strength. All the dimerization reactions were exothermic, although not spontaneous. This was mostly modulated by the strength of the hydrogen bond of the water bridge and the π-π stacking interaction. Dimers bridged by two water molecules were more stable than those with additional water molecules or without any water molecule in the bridge. Energy decomposition analysis showed that the electrostatic and polarization components were the main stabilizing terms for the hydrogen bond interaction in the bridge, contributing at least 80% of the interaction energy in all dimers. The non-covalent interaction analysis confirmed the molecular sites that had the strongest (hydrogen bond) and weak (π-π stacking) attractive interactions. They were concentrated in the water bridge and in the plane between the aromatic rings, respectively. METHODS: The density functional ωB97X-D with a dispersion correction and the Def2-SVP basis set were employed to investigate supramolecular aggregates incorporating heterocycles dimers with 0, 1, 2, and 3 water molecules forming a stabilizing bridge connecting the monomers. The non-covalent interactions were analyzed using the NCIplot software and plotted as isosurface maps using Visual Molecular Dynamics.

3.
Phys Chem Chem Phys ; 26(17): 13164-13171, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630007

RESUMO

The metathesis reaction has been an important tool in both organic and inorganic synthetic chemistry. More specifically in polymer chemistry, ring opening metathesis polymerization (ROMP), via the formation of an active metal-carbene species (MCHR), has been widely used. The elucidation of the mechanism for ROMP opened the way for the development of well-defined catalysts, suited to local conditions. In the present study, we employed density functional theory (DFT) to investigate three reaction pathways for the formation of a species capable of activating ROMP. The active species is formed from the [RuCl2(PPh3)2(pip)] complex in the presence of norbornadiene (NBD) and the carbene source ethyl diazoacetate (EDA). Formation of a hexacoordinated intermediate [RuCl2(PPh3)2(pip)(NBD)] is favored in the first step, with NBD doubly coordinated to the [RuCl2(PPh3)2(pip)] moiety. Analysis of donation (X → Ru) and back-donation (Ru → X) processes in the [RuCl2(PPh3)2(pip)(NBD)] complex shows that piperidine behaves as a σ donor, while NBD behaves as a π donor and the PPh3 groups act as π acceptors. The intensity of the orbital component is predominant in relation to the steric component in the complex. Thus, we propose that the reaction occurs through the formation of a hexacoordinated complex, followed by the dissociation of a PPh3 group, thus forming a complex where NBD is doubly coordinated to the metal center. Coordination of EDA leads finally to the catalyst capable of forming the metallocyclobutane intermediate required for the ROMP reaction.

4.
Geriatr Gerontol Aging ; 18: e0000166, Apr. 2024. tab, ilus
Artigo em Inglês, Português | LILACS | ID: biblio-1566628

RESUMO

Introduction: The World Health Organization (WHO) has proposed to monitor intrinsic capacity (IC) in the older population as a public health strategy through the Integrated Care for Older People (ICOPE) program. Although the program has been developed based on solid concepts, scientific evidence on its practical applicability is still scarce. Objectives: To evaluate IC in Brazilian older adults, its progress over time, and its association with sociodemographic and health factors and outcomes. To evaluate the psychometric properties of the WHO/ICOPE screening tool. Methods: This is a prospective multicenter cohort study with a 36-month follow-up. We will recruit 3838 people aged ≥60 years, registered in the health care units included in the study by the participating centers. We will collect sociodemographic and health data and will administer tools to assess IC domains, both those provided for in the ICOPE screening tool and the sequence of confirmatory assessments provided for in the program. Participants will be reassessed every 6 months for 36 months. Expected results: To establish the profile of IC in the study population and to understand its progress and the variables associated with the clinical outcomes of interest. To reveal the diagnostic and psychometric properties of the WHO/ICOPE screening tool. The project is funded by the Brazilian National Council for Scientific and Technological Development (CNPq). Relevance: Understanding the potential use of the ICOPE public health strategy proposed by the WHO within the scope of the Brazilian Unified Health System (SUS) by integrating several research centers in the field of Geriatrics and Gerontology throughout Brazil. (AU)


Introdução: A Organização Mundial da Saúde (OMS) propõe o monitoramento da capacidade intrínseca (CI) da população idosa como estratégia de saúde pública por meio do Programa ICOPE (Integrated Care for Older People). Embora construído com base em conceitos sólidos, a evidência científica sobre a aplicabilidade prática da proposta ainda é escassa. Objetivo: Avaliar a capacidade intrínseca da população idosa brasileira, sua trajetória e sua associação com variáveis sociodemográficas, de saúde e desfechos. Avaliar as propriedades psicométricas da ferramenta de triagem da estratégia ICOPE da OMS. Metodologia: Coorte multicêntrica prospectiva com seguimento de 36 meses. Serão recrutadas 3.838 pessoas com 60 anos ou mais, cadastradas nas unidades de saúde incluídas no estudo pelos centros participantes. Serão coletados dados sociodemográficos e de saúde e aplicados instrumentos para avaliação dos domínios da CI, tanto aqueles previstos no instrumento de triagem do ICOPE quanto a sequência de avaliações confirmatórias previstas no programa. Os participantes serão acompanhados semestralmente ao longo de 36 meses. Resultados esperados: Estabelecer o perfil da CI na população estudada, entender a sua trajetória e as variáveis associadas aos desfechos clínicos avaliados. Revelar as propriedades diagnósticas e o perfil psicométrico da ferramenta de triagem do ICOPE da OMS. O projeto tem financiamento do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Relevância: Compreensão sobre o potencial de utilização da estratégia ICOPE de saúde pública proposta pela OMS no âmbito do Sistema Único de Saúde (SUS) pela integração de diversos centros de pesquisa científica na área de Geriatria e Gerontologia de todo o Brasil. (AU)


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais
5.
Braz J Otorhinolaryngol ; 90(2): 101372, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38237484

RESUMO

OBJECTIVE: To verify changes in facial soft tissue using the RadiANT-DICOM-viewer and Dolphin Imaging software, through linear measurements of tomographic points in a 3D reconstruction of the face and volumetric evaluation with three-dimensional measurements of the upper airways of patients with transverse maxillary discrepancy undergoing Surgically Assisted Rapid Maxillary Expansion (SARME). METHODS: Retrospective, transverse, and descriptive study, through the analysis of computed tomography scans of the face of patients with transverse maxillary discrepancy, treated from July 2019 to December 2022. The sample consisted of 15 patients of both sexes, aged 21-42 years old, who underwent surgically assisted rapid maxillary expansion using the transpalatal distractor. Analysis was performed through linear, angular, and three-dimensional measurements in millimeters, in the preoperative and late four-month postoperative period, in frontal 3D tomographic images of the face, in the region of the width of the nose and alar base and also angular measurement in the lateral tomography for the angle nasolabial and upper airways of rhinopharynx, oropharynx and hypopharynx. RESULTS: There was an increase in nasal width with an average of 1.3467mm and an increase in the alar base with an average of 1.7333mm. A significant difference was found in the pre- and postoperative assessments of the measurements of nasal width, alar base and nasolabial angle, as well as the upper airways in all their extension. The results favour a better understanding of the professional and the patient regarding the diagnosis and management of patients with transverse maxillary width discrepancies. CONCLUSION: Although our study shows an increase in soft tissues after SARME, no aesthetic changes are observed clinically, and all patients report significant respiratory improvement. SARME may therefore contribute to the improvement of professionals working in the field of oral and maxillofacial surgery and orthodontics. LEVEL OF EVIDENCE: Level 4.


Assuntos
Laringe , Técnica de Expansão Palatina , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Estudos Retrospectivos , Nariz , Maxila/diagnóstico por imagem , Maxila/cirurgia , Tomografia Computadorizada de Feixe Cônico
6.
Acta fisiátrica ; 30(3): 166-172, set. 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1531048

RESUMO

Objetivo: Verificar a associação entre indicadores espirométricos e a incidência da síndrome de fragilidade em pessoas idosas. Métodos: Trata-se de um estudo com delineamento longitudinal realizado em 2014-2019, com uma amostra de estudo de 104 pessoas idosas. A variável dependente foi a síndrome de fragilidade, avaliada por meio do fenótipo de Fried et al. e as variáveis independentes foram os indicadores espirométricos, sendo eles a Capacidade Vital Forçada (CVF), Pico de Fluxo Expiratório (PFE), Volume Expiratório Forçado no primeiro segundo (VEF1), relação VEF1/CVF e o Fluxo Expiratório Forçado 25%-75% (FEF25-75%). Resultados: A incidência de pessoas idosas frágeis foi de 16,3% em ambos os sexos, sendo que o sexo masculino apresentou melhores indicadores de função pulmonar que as mulheres. Apesar disso, observamos que não houve associação entre a síndrome de fragilidade e os indicadores espirométricos (p>0,05). Conclusão: Os indicadores espirométricos não são preditores de fragilidade em pessoas idosas residentes na comunidade, após cinco anos de seguimento.


Objective: To verify the association between spirometric indicators and the incidence of frailty syndrome in elderly people. Methods: This is a study with a longitudinal design carried out in 2014-2019, with a study sample of 104 elderly people. The dependent variable was the frailty syndrome, assessed using the phenotype of Fried et al. and the independent variables were the spirometric indicators, namely Forced Vital Capacity (FVC), Peak Expiratory Flow (PEF), Forced Expiratory Volume in one second (FEV1), FEV1/FVC ratio and Forced Expiratory Flow 25%-75 % (FEF25-75%). Results: The incidence of frail elderly people was 16.3% in both genders, with males presenting better lung function indicators than females. Despite this, we observed that there was no association between the frailty syndrome and the spirometric indicators (p>0.05). Conclusion: Spirometric indicators are not predictors of frailty in community-dwelling elderly people after five years of follow-up.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36981942

RESUMO

OBJECTIVE: To evaluate and compare the effects of conventional proprioceptive training and games with motion monitoring on plantar tactile sensitivity in older women. METHODS: A randomized controlled clinical trial, with 50 older women randomized into three groups: conventional proprioception (n = 17), games with motion monitoring (n = 16), and the control (n = 17). They underwent 24 intervention sessions, three times a week, for eight weeks. The conventional proprioception group performed exercises involving gait, balance, and proprioception. The games performed by the motion monitoring group included exercises using the Xbox Kinect One video game from Microsoft®. The evaluation of tactile pressure sensitivity was performed using Semmes-Weinstein monofilaments. Intragroup comparisons between the two paired samples were performed using paired Student's t-test or Wilcoxon test. Intergroup comparisons between the three independent samples were performed using the Kruskal-Wallis test and Dunn's post hoc test, with p ≤ 0.05. RESULTS: The older women submitted to conventional games with motion monitoring training and showed improvement in plantar tactile sensitivity in the right and left feet. When comparing the intergroup results, the two training modalities obtained an improvement in the plantar tactile sensitivity of the older women when compared to the control group. CONCLUSIONS: We conclude that both training modalities may favor the improvement of plantar tactile sensitivity in older women, with no significant differences between conventional and virtual training.


Assuntos
Jogos Eletrônicos de Movimento , Jogos de Vídeo , Humanos , Feminino , Idoso , Propriocepção , Modalidades de Fisioterapia , Marcha , Equilíbrio Postural , Terapia por Exercício/métodos
8.
Chem Biodivers ; 20(2): e202200807, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36302719

RESUMO

In this study, eight naphthoquinone derivatives were synthesized in yields ranging from 52 to 96% using easy, fast, and low-cost methodologies. All naphthoquinone derivatives were screened for their in vitro anti-proliferative activities against OVCA A2780 cancer cell lines. Amongst all analysed compounds, derivatives 3-5 presented the most prominent cytotoxic potential. Naphthoquinones 3 and 4, bearing sulfur-containing groups, were identified as having high potential for ROS production, in particular the superoxide anion. Furthermore, 3 and 4 compounds caused a decrease in the cell population in G0/G1 and induced more than 90% of the cell population to apoptosis. Compound 5 did not act in any of these processes. Finally, compounds 3-5 were tested for their inhibitory ability against PI3K and MAPK. Compounds 3 and 4 do not inhibit the PI3K enzyme. On the other hand, the naphthoquinone-polyphenol 5 was only able to inhibit the percentage of cells expressing pERK.


Assuntos
Antineoplásicos , Naftoquinonas , Neoplasias Ovarianas , Humanos , Feminino , Linhagem Celular Tumoral , Naftoquinonas/farmacologia , Antineoplásicos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células , Relação Estrutura-Atividade
9.
J Mol Model ; 28(12): 394, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36409425

RESUMO

The role played by the metal - support (MSI) and metal - metal (MMI) interactions on two important processes in controlling the catalyst performance - nucleation and molecular adsorption - has been investigated using density functional theory (DFT), by means of B3LYP functional, combined with localized molecular orbital energy decomposition analysis (LMOEDA), and natural bond orbital (NBO) calculations, with aid of a Pd4/γ-alumina (110D) model (Pd4/Al13O23H7). Our results indicate the occurrence of an electronic metal - support interaction (EMSI) which induces a most intense charge transfer in the Pd4 → γ-alumina backdonation direction, most expressive in Pd → Al, promoting an electronic redistribution within the units and attenuating the MMI. Nevertheless, the MSI/MMI synergistic effect seems to favor slightly the nucleation of a fifth palladium atom, leading to a distorted square pyramidal arrangement for Pd5. The LMOEDA analysis points to a mostly covalent character in the Pd - Al bonds, whereas the Pd - O bonds are mainly electrostatic in nature. The palladium atoms deposited on oxygen anions are the acid centers, where both NO molecule and an additional palladium atom anchor more strongly. In addition, the MSI/MMI effect, through the electronic and geometric contributions, drives the adsorption of the NO molecule to the mode which most favors the Pd → NO (4dz2 → 2π*) backdonation (bridge mode). MSI and MMI effects on the nature of the Pd - O (electrostatic) and Pd - Al (covalent) bonds, charge transfer into Pd4/γ-Al2O3 (110D) interface (back donation) and preferential site for adsorption of a single NO molecule and an additional Pd atom (Pd - O).

10.
Ciênc. Saúde Colet. (Impr.) ; Ciênc. Saúde Colet. (Impr.);27(8): 3249-3260, ago. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1384468

RESUMO

Resumo O objetivo deste artigo é investigar a associação entre a Pressão Inspiratória Máxima (PImáx) e Pressão Expiratória Máxima (PEmáx) com a incidência da síndrome de fragilidade (SF), além de testar a capacidade preditiva da PImáx e PEmáx em discriminar a SF em idosos, de acordo com o sexo. Estudo longitudinal com cinco anos de seguimento (2014-2019), realizado com 104 idosos cadastrados na Estratégia Saúde da Família de um município da Bahia. A incidência da síndrome de fragilidade foi diagnosticada de acordo os critérios propostos por Fried et al., utilizando dados de 2019, após cinco anos de seguimento. A PImáx e PEmáx foram avaliadas conforme recomendações da Sociedade Brasileira de Pneumologia e Tisiologia em 2014 (linha de base). A incidência total da SF foi de 16,3% (IC95%: 9,2-23,6), sendo 13,6% (IC95%: 4,56-22,55) no sexo feminino e 20,0% (IC95%: 7,85-32,15) no sexo masculino. Os valores médios da PImáx e PEmáx foram, respectivamente, 60,8±21,2 cmH2O e 76,7±23,1 cmH2O no sexo feminino, e 79,5±27,0 cmH2Oe 114,7±29,8 cmH2O no sexo masculino. A SF esteve associada à PEmáx em idosos do sexo masculino (RR ajustado: 0,96; IC95%: 0,95-0,98; p-valor: 0,002), indicando que o aumento de 1 cmH2O da PEmáx reduz em 4% o risco de desenvolver a síndrome de fragilidade.


Abstract This article aims to investigate the association between maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) with the incidence of frailty syndrome (FS), in addition to testing the predictive ability of MIP and MEP to discriminate FS in elderly adults, according to sex. It is a longitudinal study with a five-year follow-up period (2014-2019), carried out with 104 elderly adults registered in the Family Health Strategy of a municipality in Bahia. The incidence of frailty syndrome was diagnosed according to criteria proposed by Fried et al., using data from 2019, after a five-year follow-up. The MIP and MEP were evaluated according to the recommendations of the Brazilian Society of Pulmonology and Phthisiology data in 2014 (baseline data). The total incidence of frailty syndrome was 16.3% (95%CI: 9.2-23.6), with 13.6% (95%CI: 4.56-22.55) in women and 20% (95%CI: 7.85-32.15) in men. The mean values of MIP and MEP were, respectively, 60,8±21,2 cmH2O and 76,7±23,1 cmH2O in women, and 79,5±27,0 cmH2O and 114,7±29,8 cmH2O in men. The frailty syndrome was associated with MEP in elderly adult men (adjusted RR: 0.96; 95%CI: 0.95-0.98; P-value: 0.002), indicating that the increase of 1cmH2O in MEP reduces by 4% the risk of developing the syndrome.

11.
J Mol Model ; 28(8): 239, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35908141

RESUMO

Plants from the Garcinia genus have been used worldwide due to their therapeutic properties. Among the various metabolites isolated from this genus, 7-epi-clusianone, a tetraprenylated benzophenone, stands out for its wide range of identified biological activities. This benzophenone can exist in five tautomeric forms, although the benzene-d6 and chloroform-d3 solution nuclear magnetic resonance (NMR) spectra revealed only two tautomeric forms (B and C) in equilibrium, with concentration ratio depending on the solvent in which the spectrum was obtained. Calculated energy values suggested that tautomeric forms B and E would be prevalent in benzene-d6 solution, in contrast to the experimental data. Considering this conflicting result, we employed the statistical DP4 + method based on 13C and 1H NMR chemical shift calculations, in the gas phase and in benzene-d6 solution, to confirm that the B and C tautomeric forms of 7-epi-clusianone are the most prevalent in the experimental conditions.


Assuntos
Benzeno , Benzofenonas , Benzoquinonas , Espectroscopia de Ressonância Magnética , Modelos Teóricos , Conformação Molecular
12.
Cien Saude Colet ; 27(8): 3249-3260, 2022 Aug.
Artigo em Português | MEDLINE | ID: mdl-35894335

RESUMO

This article aims to investigate the association between maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) with the incidence of frailty syndrome (FS), in addition to testing the predictive ability of MIP and MEP to discriminate FS in elderly adults, according to sex. It is a longitudinal study with a five-year follow-up period (2014-2019), carried out with 104 elderly adults registered in the Family Health Strategy of a municipality in Bahia. The incidence of frailty syndrome was diagnosed according to criteria proposed by Fried et al., using data from 2019, after a five-year follow-up. The MIP and MEP were evaluated according to the recommendations of the Brazilian Society of Pulmonology and Phthisiology data in 2014 (baseline data). The total incidence of frailty syndrome was 16.3% (95%CI: 9.2-23.6), with 13.6% (95%CI: 4.56-22.55) in women and 20% (95%CI: 7.85-32.15) in men. The mean values of MIP and MEP were, respectively, 60,8±21,2 cmH2O and 76,7±23,1 cmH2O in women, and 79,5±27,0 cmH2O and 114,7±29,8 cmH2O in men. The frailty syndrome was associated with MEP in elderly adult men (adjusted RR: 0.96; 95%CI: 0.95-0.98; P-value: 0.002), indicating that the increase of 1cmH2O in MEP reduces by 4% the risk of developing the syndrome.


O objetivo deste artigo é investigar a associação entre a Pressão Inspiratória Máxima (PImáx) e Pressão Expiratória Máxima (PEmáx) com a incidência da síndrome de fragilidade (SF), além de testar a capacidade preditiva da PImáx e PEmáx em discriminar a SF em idosos, de acordo com o sexo. Estudo longitudinal com cinco anos de seguimento (2014-2019), realizado com 104 idosos cadastrados na Estratégia Saúde da Família de um município da Bahia. A incidência da síndrome de fragilidade foi diagnosticada de acordo os critérios propostos por Fried et al., utilizando dados de 2019, após cinco anos de seguimento. A PImáx e PEmáx foram avaliadas conforme recomendações da Sociedade Brasileira de Pneumologia e Tisiologia em 2014 (linha de base). A incidência total da SF foi de 16,3% (IC95%: 9,2-23,6), sendo 13,6% (IC95%: 4,56-22,55) no sexo feminino e 20,0% (IC95%: 7,85-32,15) no sexo masculino. Os valores médios da PImáx e PEmáx foram, respectivamente, 60,8±21,2 cmH2O e 76,7±23,1 cmH2O no sexo feminino, e 79,5±27,0 cmH2Oe 114,7±29,8 cmH2O no sexo masculino. A SF esteve associada à PEmáx em idosos do sexo masculino (RR ajustado: 0,96; IC95%: 0,95-0,98; p-valor: 0,002), indicando que o aumento de 1 cmH2O da PEmáx reduz em 4% o risco de desenvolver a síndrome de fragilidade.


Assuntos
Fragilidade , Pressões Respiratórias Máximas , Adulto , Idoso , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Músculos Respiratórios
13.
J Mol Model ; 28(8): 222, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852644

RESUMO

Nonlinear optical materials have been investigated recently due to their potential technological applications in information storage and communications. In this context, semi-organic crystals can effectively combine the desired nonlinear optical properties of amino acids with the promising mechanical and thermal properties of inorganic materials. In this work, we have synthesized and characterized a semi-organic crystal of the amino acid L-histidine and hydrofluoric acid and investigated the chemical interactions between the organic and inorganic moieties. The crystal of L-histidine bis(fluoride) has been produced by slow solvent evaporation and characterized by X-ray diffraction (XRD) crystallography and thermogravimetric and differential thermal analyses. The XRD conducted using the Rietveld method shows that the unit cell is orthorhombic with the P21212 space group and contains four L-histidine bis(fluoride) units. Both differential thermal analysis and temperature-dependent XRD show that the crystals are thermally stable up to 191°C and do not undergo phase transition. The computational Hirshfeld surface analysis of the crystal structure reveals the main intermolecular interactions. Density functional theory has been employed to calculate the ionic interaction energy and electrostatic potential maps and confirm the spontaneity of ionic association at 191°C. The combined experimental and computational results show that the thermal stability of the semi-organic L-histidine bis(fluoride) crystal makes it suitable for nonlinear optical applications in optical sensing and communication systems.


Assuntos
Fluoretos , Histidina , Cristalização , Cristalografia por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
Plant Dis ; 106(10): 2672-2677, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35224984

RESUMO

The combination of plant density, fungicide, and levels of genotype resistance to white mold (WM) has not been studied for its effect on performance of common bean with type III growth habit under WM pressure. We established four sprinkler-irrigated trials in the fall to winter season in Brazil, combining density (8, 14, 20, or 26 plants/m2), genotype (susceptible or partially resistant to WM), and fungicide to manage WM (two fluazinam applications or without fluazinam) at 0.5 m row spacing in fields infested with sclerotia. One trial was established in a warm region, aiming to obtain low WM pressure. For three trials, the linear mixed model was used. WM pressure in the trials ranged from low to high. Genotype × density × fungicide and genotype × density interactions were not significant for incidence, severity, and yield for all trials. In the three trials, severity was 29% lower at eight than at 26 plants/m2, and yield at 14 plants/m2 (3,294 kg/ha) was 14% higher than yield at eight plants/m2 (P = 0.035) where fluazinam was applied. However, without fluazinam, density did not affect yield. In conclusion, choices of plant density for type III bean cultivars do not need to take into account their resistance levels to WM in the fall to winter season. However, fungicide treatment to manage WM affects the choice of density, with 8 to 12 plants/m2 recommended if fungicide is not an option to manage WM (as in organic systems), and 10 to 14 plants/m2 recommended if fungicide applications are likely.


Assuntos
Ascomicetos , Fungicidas Industriais , Phaseolus , Aminopiridinas , Fungicidas Industriais/farmacologia , Hábitos , Doenças das Plantas/prevenção & controle , Plantas
15.
J Bras Pneumol ; 48(1): e20210335, 2022.
Artigo em Inglês, Português | MEDLINE | ID: mdl-35137870

RESUMO

OBJECTIVE: To compare maximum respiratory pressures and spirometric parameters among elderly individuals classified as having no sarcopenia, probable sarcopenia, and confirmed sarcopenia, and to test the ability of these variables to discriminate sarcopenia in a community-dwelling elderly population. METHODS: This was a cross-sectional study involving 221 elderly (≥ 60 years of age) individuals of both sexes. Sarcopenia was diagnosed in accordance with the new consensus of the European Working Group on Sarcopenia in Older People. Maximum respiratory pressures and spirometry parameters were assessed. RESULTS: The prevalences of probable sarcopenia and confirmed sarcopenia were 20.4% and 4.1%, respectively. Regardless of the sex, those with confirmed sarcopenia had significantly lower MEP than those with no sarcopenia and probable sarcopenia, whereas only males with confirmed sarcopenia presented with significantly lower MIP than did the other individuals. There was an inverse association of MIP and MEP with sarcopenia, indicating that the decrease by 1 cmH2O in these parameters increases the chance of sarcopenia by 8% and 7%, respectively. Spirometric parameters were not associated with sarcopenia. Cutoff points for MIP and MEP, respectively, were ≤ 46 cmH2O and ≤ 50 cmH2O for elderly women, whereas they were ≤ 63 cmH2O and ≤ 92 cmH2O for elderly men, and both were identified as predictors of sarcopenia (area under the ROC curve > 0.70). CONCLUSIONS: Sarcopenia was associated with lower maximum respiratory pressures, but not with spirometric parameters. Maximum respiratory pressures can be used as markers of sarcopenia in a community-dwelling elderly population regardless of the sex.


Assuntos
Pressões Respiratórias Máximas , Sarcopenia , Idoso , Estudos Transversais , Feminino , Humanos , Vida Independente , Masculino , Músculos Respiratórios , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia
16.
J Agric Food Chem ; 70(6): 1799-1809, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35130436

RESUMO

To investigate the herbicidal potential of 2,5-diketopiperazines (2,5-DKPs), we applied a known protocol to produce a series of 2,5-DKPs through intramolecular N-alkylation of Ugi adducts. However, the method was not successful for the cyclization of adducts presenting aromatic rings with some substituents at the ortho position. Results from DFT calculations showed that the presence of voluminous groups at the ortho position of a benzene ring results in destabilization of the transition structure. Lower activation enthalpies for the SN2-type cyclization of Ugi adducts were obtained when bromine, instead of a chlorine anion, is the leaving group, indicating that the activation enthalpy for the cyclization step controls the formation of the 2,5-DKP. Some Ugi adducts and 2,5-DKPs formed crystals with suitable qualities for single-crystal X-ray diffraction data collection. Phytotoxic damage of some 2,5-DKPs on leaves of the weed Euphorbia heterophylla did not differ from those caused by the commercial herbicide diquat.


Assuntos
Herbicidas , Alquilação , Teoria da Densidade Funcional , Dicetopiperazinas , Estrutura Molecular , Raios X
17.
Magn Reson Chem ; 60(4): 434-441, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34741339

RESUMO

Recently, structural elucidation of natural products has undergone a revolution. The combined use of different modern spectroscopic methods has allowed obtaining a complete structural assignment of natural products using small amounts of sample. However, despite the extraordinary ongoing advances in spectroscopy, the mischaracterization of natural products has been and remains a recurrent problem, especially when the substance presents several stereogenic centers. The misinterpretation of nuclear magnetic resonance (NMR) data has resulted in frequent reports addressing structural reassignment. In this context, a great effort has been devoted to developing quantum chemical calculations that simulate NMR parameters accurately, allowing to achieve a more precise spectral interpretation. In this work, we employed a protocol for theoretical calculations of 1 H NMR chemical shifts and coupling constants using density functional theory (DFT), followed by the application of the DP4+ method to revisit the structure of Heliannuol L, a member of the Heliannuol class, isolated from Helianthus annuus. Our results indicate that the originally proposed structure of Heliannuol L needs a stereochemical reassignment, placing the hydroxyl bonded to C10 in the opposite side of the methyl and hydroxyl groups bonded to C7 and C8, respectively.


Assuntos
Produtos Biológicos , Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular
18.
J. bras. pneumol ; J. bras. pneumol;48(1): e20210335, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360538

RESUMO

ABSTRACT Objective: To compare maximum respiratory pressures and spirometric parameters among elderly individuals classified as having no sarcopenia, probable sarcopenia, and confirmed sarcopenia, and to test the ability of these variables to discriminate sarcopenia in a community-dwelling elderly population. Methods: This was a cross-sectional study involving 221 elderly (≥ 60 years of age) individuals of both sexes. Sarcopenia was diagnosed in accordance with the new consensus of the European Working Group on Sarcopenia in Older People. Maximum respiratory pressures and spirometry parameters were assessed. Results: The prevalences of probable sarcopenia and confirmed sarcopenia were 20.4% and 4.1%, respectively. Regardless of the sex, those with confirmed sarcopenia had significantly lower MEP than those with no sarcopenia and probable sarcopenia, whereas only males with confirmed sarcopenia presented with significantly lower MIP than did the other individuals. There was an inverse association of MIP and MEP with sarcopenia, indicating that the decrease by 1 cmH2O in these parameters increases the chance of sarcopenia by 8% and 7%, respectively. Spirometric parameters were not associated with sarcopenia. Cutoff points for MIP and MEP, respectively, were ≤ 46 cmH2O and ≤ 50 cmH2O for elderly women, whereas they were ≤ 63 cmH2O and ≤ 92 cmH2O for elderly men, and both were identified as predictors of sarcopenia (area under the ROC curve > 0.70). Conclusions: Sarcopenia was associated with lower maximum respiratory pressures, but not with spirometric parameters. Maximum respiratory pressures can be used as markers of sarcopenia in a community-dwelling elderly population regardless of the sex.


RESUMO Objetivo: Comparar as pressões respiratórias máximas e parâmetros espirométricos entre idosos classificados como sem sarcopenia, sarcopenia provável e sarcopenia confirmada e testar a capacidade dessas variáveis de discriminar sarcopenia em idosos residentes em comunidade. Métodos: Estudo transversal envolvendo 221 idosos (≥ 60 anos) de ambos os sexos. Sarcopenia foi diagnosticada de acordo com o novo consenso do Grupo de Trabalho Europeu sobre Sarcopenia em Pessoas Idosas. As pressões respiratórias máximas e parâmetros espirométricos foram avaliados. Resultados: As prevalências de sarcopenia provável e sarcopenia confirmada foram de 20,4% e 4,1%, respectivamente. Independentemente do sexo, aqueles com sarcopenia confirmada apresentaram PEmáx significativamente menor do que aqueles sem sarcopenia e provável sarcopenia, enquanto apenas os homens com sarcopenia confirmada apresentaram PImáx significativamente menor do que os outros indivíduos. Houve uma associação inversa de PImáx e PEmáx com sarcopenia, indicando que a diminuição de 1 cmH2O nesses parâmetros aumenta a chance de sarcopenia em 8% e 7%, respectivamente. Os parâmetros espirométricos não foram associados à sarcopenia. Os pontos de corte para PImáx e PEmáx, respectivamente, foram ≤ 46 cmH2O e ≤ 50 cmH2O para mulheres idosas, enquanto foram ≤ 63 cmH2O e ≤ 92 cmH2O para homens idosos, e ambas foram identificadas como preditores de sarcopenia (ASC ROC > 0,70). Conclusões: A sarcopenia associou-se a pressões respiratórias máximas mais baixas, mas não a parâmetros espirométricos. As pressões respiratórias máximas podem ser usadas como marcadores de sarcopenia em idosos residentes em comunidade, independentemente do sexo.

19.
Rev. Ciênc. Plur ; 8(1): e25556, 2022. tab, ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1349020

RESUMO

Introdução:a Mortalidade Materna é um problema de saúde pública em todo mundo. A Agenda 2030 tem como meta reduzir a mortalidade materna em 5% ao ano. Com a Covid19 a razão de mortes maternas tem aumentado muito em todos os países. A divulgação de eventos que contribuam com a redução deste agravo é uma estratégia de grande impacto. As mídias sociais têm-semostradas eficientes na divulgação de eventos na área da saúde Objetivo:relatar a experiência no uso de mídias sociais na divulgação e promoção de eventos para redução da mortalidade materna. Metodologia:Estudo descritivo do tipo relato de experiência vivenciado por discentes, profissionais e orientadores envolvidos no processo de divulgação científica no Instagram® da Universidade Aberta do Sistema Único de Saúde, facebook® e site da Universidade Federal do Piauí. Resultados:Assim, desenvolveram-se matérias informativos com chamamento aberto dos profissionais de Saúde para participarem dos eventos sobre mortalidade materna oferecidos pela Universidade Aberta do Sistema Único de Saúde da Universidade Federal do Piauí. Discussão: O uso das mídias sociais, principalmente o Instagram® está cada vez mais em crescimento, o que possibilita a divulgação e adesão dos públicos alvo. A utilização das mídias sociais mostraram-se efetivas na divulgação dos eventos científicos oferecidos na Universidade Aberta do Sistema Único de Saúde, tendo em vista o amplo alcance em nível nacional do público alvo contribuindo significativamente com a qualificação dos trabalhadores e em um efeito rebote na redução da mortalidade materna.Conclusões:Concluiu-se que a contribuição das mídias sociais tem um papel importante para a participação do público participantes e que deve-se investir nessa ferramenta para melhor executar as propostas de capacitações ofertadas.


Introduction:Maternal Mortalityis a public health problem worldwide. Agenda 2030 aims to reduce maternal mortality by 5% per year. With Covid19 thematernal deathsratio has increased a lot in all countries. The dissemination of events that contribute to the reduction of this grievanceis a strategy with great impact. Social media has been shown to be efficient in the dissemination of events in the health area Objective:to report the experience of using social media in the dissemination and promotion of events to reduce maternal mortality. Methodology:Descriptive study of the experience report type experienced by students, professionals and advisorsinvolved in the process of scientific dissemination on Instagram® of the Open University of the Unified Health System, facebook® and the website of the Federal University of Piauí. Results:Thus, informative materials were developed with an open call for health professionals to participate in events on maternal mortality offered by Open University of the Unified Health System of the Federal University of Piauí. Discussion:The use of social media, especially Instagram®, is increasingly growing, which enables the dissemination and adhesion of target audiences. The use of social media proved to be effective in the dissemination of scientific events offered at the Open University of the Unified Health System, in view of the wide reach at the national level of the target audience, significantly contributing to the qualification of workers and in a rebound effect in reduction of maternal mortality. Conclusions:It was concluded that the contribution of social media plays an important role in the participation of the participating public and that this tool should be invested in to better implement the training proposals offered (AU).


Introducción:La Mortalidad Maternaes un problema de saludpública a nivel mundial. La Agenda 2030 tiene como objetivo reducir la mortalidad materna en un 5% anual. La difusión de eventos que contribuyan a la reducción de estos agravos es una estrategia de gran impacto. Se ha demostrado que las redes sociales soneficientes en la difusión de eventos en el área de la salud. Objetivo:reportar la experiencia del uso de las redes sociales en la difusión y promoción de eventos para la reducción de la mortalidad materna. Metodología:Estudio descriptivo del tipo de relato de experiencia vivida por estudiantes, profesionales y asesores involucrados en el proceso de divulgación científica en Instagram® de la Universidad Abierta del Sistema Único de Salud, facebook® y el sitio web de la Universidad Federal de Piauí. Resultados:Así, se desarrollaron materiales informativos con una convocatoria abierta para que los profesionales de la salud participen en eventos sobre mortalidad materna ofrecidos por la Universidad Abierta del Sistema Único de Salud de la UniversidadFederal de Piauí. Discusión:El uso de las redes sociales, especialmente Instagram®, es cada vez más creciente, lo que permite la difusión y adhesión de los públicos objetivo. El uso de las redes sociales demostró ser efectivo en la difusión de los eventos científicos que se ofrecen en la Universidad Abierta del Sistema Único de Salud, dado el amplio alcance a nivel nacional del público objetivo, contribuyendo significativamente a la calificación de los trabajadores y en un efecto rebote en la reducción dela mortalidad materna. Conclusiones:Se concluyó que el aporte de las redes sociales juega un papel importante en la participación del público participante y que se debe invertir en esta herramienta para implementar mejor las propuestas de capacitación que se ofrecen (AU).


Assuntos
Humanos , Feminino , Gravidez , Mortalidade Materna , Eventos Científicos e de Divulgação , Mídias Sociais , Redes Sociais Online , Brasil , Epidemiologia Descritiva , Estratégias de Saúde , COVID-19
20.
Motriz (Online) ; 28: e10220005822, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406013

RESUMO

Abstract Aim: This study aimed to identify the prevalence and factors associated with dynapenia in older women, considering different cutoff points as diagnostic criteria. Methods: This epidemiological study was conducted with 205 older women (72.7 ± 7.1 years). Dynapenia was diagnosed using the handgrip strength test (HGS) using two cutoff points (< 16 or < 20 kgf). Socio-demographic, behavioral, and health status information was obtained from a specific form; nutritional status was assessed by body mass index, and the International Physical Activity Questionnaire identified the level of physical activity. Results: The prevalence of dynapenia was 14.1% (HGS < 16 kgf) and 46.3% (HGS < 20 kgf) (p < 0.001). It was also observed that older women with family income ≤ 1 minimum wage and those with low weight presented, respectively, 2.22 (95%CI: 1.12-4.39) and 4.72 (95%CI: 1.64-13.58) times higher probability of dynapenia identified by HGS < 16 kgf. Moreover, for the cutoff point < 20 kgf, the probability of dynapenia was higher in women aged ≥ 80 years (PR:1.91; 95%CI: 1.23-2.95), in insufficiently active women (PR: 1.34; 95%CI: 1.01-2.57), among those with low weight (PR: 1.61; 95%CI: 1.01-2.57), and in those who reported falls (PR:1.42; 95%CI: 1.04-1.96). Conclusion: Therefore, it is concluded that there is a difference between the prevalence and factors associated with dynapenia when different cutoff points are adopted.

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