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1.
Inorg Chem ; 63(4): 1840-1852, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38232297

RESUMO

The design of rare-earth-doped upconversion/downshifting nanoparticles (NPs) for theoretical use in nanomedicine has garnered considerable interest. Previous research has emphasized luminescent nanothermometry and photothermal therapy, while three-dimensional (3D) near-infrared (NIR) luminescent tracers have received less attention. Our study introduces Nd3+-, Yb3+-, and Ho3+-doped NaYF4 core-shell luminescent NPs as potential multiparametric nanothermometers and NIR imaging tracers. Nd3+ sensitizes at 804 nm, while Yb3+ bridges to activators Ho3+. We evaluated the photoluminescence properties of Nd3+-, Yb3+-, and Ho3+-doped core and core-shell NPs synthesized via polyol-mediated and thermal decomposition methods. The NaYF4:NdYbHo(7/15/3%)@NaYF4:Nd(15%) core-shell NPs demonstrate competitive nanothermometry capabilities. Specifically, the polyol-synthesized sample exhibits a sensitivity of 0.27% K-1 at 313 K (40 °C), whereas the thermally decomposed synthesized sample shows a significantly higher sensitivity of 0.55% K-1 at 313 K (40 °C) in the near-infrared range. Control samples indicate back energy transfer processes from both Yb and Ho to Nd, while Yb to Ho energy transfer enhances Ho3+-driven upconversion transitions in green and red wavelengths, suggesting promise for photodynamic therapy. Fluorescence molecular tomography confirms 3D NIR fluorescence nanoparticle localization in a biological media after injection, highlighting the potential of core-shell NPs as NIR luminescent tracers. The strategy's clinical impact lies in photothermal treatment planning, leveraging core-shell NPs for (pre)clinical applications, and enabling the easy addition of new functionalities through distinct ion doping.

2.
Emerg Infect Dis ; 29(7): 1443-1446, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37347822

RESUMO

We found serologic evidence of spotted fever group Rickettsia in humans and dogs and typhus group Rickettsia in dogs in Reynosa, Mexico. Our investigation revealed serologic samples reactive to spotted fever group Rickettsia in 5 community members, which highlights a potential rickettsial transmission scenario in this region.


Assuntos
Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Tifo Epidêmico Transmitido por Piolhos , Humanos , Animais , Cães , Rickettsia/genética , México/epidemiologia , Anticorpos Antibacterianos , Rickettsiose do Grupo da Febre Maculosa/diagnóstico , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/veterinária
3.
Inorg Chem ; 62(47): 19195-19207, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37956256

RESUMO

This work reports the structural characterization and photophysical properties of DyIII, TbIII, and EuIII coordination polymers with two phenoxo-triazole-based ligands [2,6-di(1H-1,2,4-triazole-1-yl-methyl)-4-R-phenoxo, LRTr (R = CH3; Cl)]. These ligands permitted us to obtain isostructural polymers, described as a 1D double chain, with LnIII being nona-coordinated. The energies of the ligand triplet (T1) states were estimated using low-temperature time-resolved emission spectra of YIII analogues. Compounds with LClTr present higher emission intensity than those with LMeTr. The emission of TbIII compounds was not affected by the different excitation wavelengths used and was emitted in the pure green region. In contrast, DyLMeTr emits in the blue-to-white region, while the luminescence of DyLClTr remains in the white region for all excitation wavelengths. On the other hand, EuIII compounds emit in the blue (ligand) or red region (EuIII) depending on the substituent of the phenoxo moiety and excitation wavelength. Theoretical calculations were employed to determine the excited states of the ligands by using time-dependent density functional theory. These calculations aided in modeling the intramolecular energy transfer and rationalizing the optical properties and demonstrated that the sensitization of the LnIII ions is driven via S1 → LnIII, a process that is less common as compared to T1 → LnIII.

4.
Inorg Chem ; 61(41): 16347-16355, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36198146

RESUMO

Two mononuclear DyIII complexes, [Dy(L1)(NCS)3] (Dy-EDA) and [Dy(L2)(NCS)3] (Dy-DAP), where Ln (n = 1-2) corresponds to a macrocyclic ligand derived from 2,6-pyridinedicarboxaldehyde and ethylenediamine (L1) and 1,3-diaminepropane (L2) were immobilized on functionalized silicon-based surfaces. This was achieved by the microcontact printing (µCP) technique, generating patterns on a functionalized surface via covalent bond formation through the auxiliary -NCS ligands present in the macrocyclic complex species. With this strategy, it was possible to control the position of the immobilized molecules on the surface. Water contact angle measurements, X-ray photoelectron spectroscopy (XPS), infrared reflection absorption spectra (IRRAS), and atomic force microscopy (AFM) confirmed that the surfaces were successfully functionalized. Furthermore, the optical properties in a broad temperature range were investigated for the as-prepared compounds. At room temperature, Dy-EDA was shown to emit in the deep blue region (Commission Internationald'Eclairage (CIE): (0.175, 0.128)), while Dy-DAP in the white region (CIE: (0.252, 0.312)). The different CIE values were due to the contribution of the strong emission of the ligand in the case of Dy-EDA. Besides, surface photoluminescence measurements showed that the immobilized complexes retained their bulk emissive properties.

5.
Rev Panam Salud Publica ; 46: e110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016838

RESUMO

There is a lack of real-world surveillance studies on reports of adverse events associated with COVID-19 vaccination, as well as comparative analyses of adverse events from vaccines with different platforms. This observational, descriptive, retrospective study based on secondary data describes the adverse events following immunization (AEFIs) related to the first 145 000 doses of COVID-19 vaccines delivered in Aracaju municipality, Sergipe state, northeast Brazil. Records of AEFIs were collected using the e-SUS Notifica database for January 19 to April 30, 2021. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for AEFIs and the type of COVID-19 vaccine, either CoronaVac (Sinovac-Butantan) or Oxford-AstraZeneca (Fiocruz). A total of 474 AEFIs (32.7 events/10 000 doses) from 254 individuals were reported and analyzed, and all of them were classified as non-serious. There was an association between the use of the CoronaVac vaccine and headache (OR = 2.1; 95% CI: 1.4-3.2), pain at the injection site (OR = 9.6; 95% CI: 3.9-23.8), lethargy (OR = 5.2; 95% CI: 1.8-14.8), fatigue (OR = 10.1; 95% CI: 2.4-42.3), diarrhea (OR = 4.4; 95% CI: 1.5-12.5) and cold-like symptoms (OR = 8.0; 95% CI: 1.9-34.0). However, the proportion of individuals reporting fever was higher among those who received the Oxford-AstraZeneca vaccine (OR = 3.1; 95% CI 1.5-6.4). This population-based observational study strengthens the evidence for the safety and tolerability of the CoronaVac and Oxford-AstraZeneca vaccines used against COVID-19.


Hay una carencia de estudios de vigilancia en el mundo real sobre la notificación de eventos adversos asociados a la vacunación contra la COVID-19, así como de análisis comparativos de los eventos adversos de vacunas con diferentes plataformas. En este estudio observacional, descriptivo y retrospectivo basado en datos secundarios se describen los eventos adversos supuestamente atribuibles a la vacunación o inmunización (ESAVI) relacionados con las primeras 145 000 dosis de vacunas contra la COVID-19 administradas en el municipio de Aracaju, estado de Sergipe, en la región Noreste de Brasil. Se recopilaron registros de los ESAVI del 19 de enero al 30 de abril del 2021 con la base de datos e-SUS Notifica. Se calcularon las razones de posibilidades (OR, por su sigla en inglés) y los intervalos de confianza (IC) del 95 % para los ESAVI y el tipo de vacuna contra la COVID-19 (CoronaVac [Sinovac-Butantan] o bien Oxford-AstraZeneca [Fiocruz]). Se notificaron y analizaron un total de 474 ESAVI (32,7 eventos/10 000 dosis) de 254 personas, y todos se clasificaron como no graves. Se encontró una relación entre el empleo de la vacuna CoronaVac y la cefalea (OR = 2,1; IC del 95 %: 1,4­3,2), dolor en el lugar de la inyección (OR = 9,6; IC del 95 %: 3,9­23,8), letargo (OR = 5,2; IC del 95 %: 1,8­14,8), cansancio (OR = 10,1; IC del 95 %: 2,4­42,3), diarrea (OR = 4,4; IC del 95 %: 1,5­12,5) y síntomas similares al resfriado (OR = 8,0; IC del 95 %: 1,9 a 34,0). Sin embargo, la proporción de pacientes que notificaron fiebre fue mayor entre los que recibieron la vacuna de Oxford-AstraZeneca (OR = 3,1; IC del 95 %: 1,5 a 6,4). Este estudio observacional poblacional refuerza la evidencia sobre la seguridad y tolerabilidad de las vacunas CoronaVac y Oxford-AstraZeneca empleadas contra la COVID-19.


Faltam estudos de vigilância no mundo real sobre relatórios de eventos adversos associados à vacinação contra a COVID-19, bem como análises comparativas de eventos adversos decorrentes de vacinas com diferentes plataformas. Este estudo observacional, descritivo e retrospectivo baseado em dados secundários descreve os eventos adversos pós-vacinação (EAPV) relacionados com as primeiras 145 mil doses de vacinas contra a COVID-19 entregues no município de Aracaju, capital do estado de Sergipe, na região Nordeste do Brasil. Os registros de EAPV foram coletados usando o sistema e-SUS Notifica com referência ao período de 19 de janeiro a 30 de abril de 2021. Razões de chances (odds ratios, ORs) e intervalos de confiança (IC) de 95% foram calculados para os EAPV e o tipo de vacina contra a COVID-19: CoronaVac (Sinovac-Butantan) ou Oxford-AstraZeneca (Fiocruz). Um total de 474 EAPV (32,7 eventos/10 mil doses) de 254 indivíduos foram relatados e analisados, e todos foram classificados como não graves. Houve uma associação entre o uso da vacina CoronaVac e cefaleia (OR = 2,1; IC 95%: 1,4-3,2), dor no local da injeção (OR = 9,6; IC 95%: 3,9-23,8), letargia (OR = 5,2; IC 95%: 1,8-14,8), cansaço (OR = 10,1; IC 95%: 2,4-42,3), diarreia (OR = 4,4; IC 95%: 1,5-12,5 e sintomas gripais (OR = 8,0; IC 95%: 1,9-34,0). Contudo, a proporção de indivíduos que relataram febre foi superior entre os que receberam a vacina Oxford-AstraZeneca (OR = 3,1; IC 95%: 1,5-6,4). Este estudo observacional de base populacional reforça as evidências da segurança e tolerabilidade das vacinas CoronaVac e Oxford-AstraZeneca usadas contra a COVID-19.

6.
Inorg Chem ; 60(9): 6176-6190, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33861078

RESUMO

The reaction of aqueous solutions of EuIII, TbIII, and GdIII ions with Na2Hpcpa [H3pcpa = N-(4-carboxyphenyl)oxamic acid] afforded three new isostructural oxamate-containing lanthanide(III) coordination polymers of general formula {LnIII2(Hpcpa)3(H2O)5·H2O}n [Ln = Eu (1),Tb (2), and Gd(3)]. Their structure is made up of neutral zigzag chains running parallel to the [101] direction where double syn-syn carboxylate(oxamate)-bridged dilanthanide(III) pairs (Ln1 and Ln2) are linked by three Hpcpa2- ligands, one of them with the µ-κ2O,O':κO″ coordination mode and the other two with the µ3-κ2O,O':κO″:κO'''. Additionally, two of those chains are interlinked through hydrogen bonding and π-π type interactions, resulting in a porous structure with channels where water molecules are hosted. The emission properties of 1 and 2 are evaluated as a function of the temperature, exhibiting an emission in red and green, respectively. The external quantum yield for 2 is approximately 7 times that obtained for 1, indicating that the oxamate ligand is a better sensitizer for TbIII ions. The temperature dependence of the dc magnetic properties of 1-3 reveals a different magnetic behavior depending on the nature of the LnIII ion. A continuous decrease of χMT occurs for 1 upon cooling, and finally χMT tends to vanish, as expected for the thermal depopulation of the six magnetic 7FJ excited states (J = 1-6) of the EuIII ion with a nonmagnetic 7F0 ground state. χMT for 2 decreases sharply with decreasing the temperature due to the depopulation of the splitted mJ levels of the 7F7 ground state of the magnetically anisotropic TbIII ion. A very weak antiferromagnetic interaction between the magnetically isotropic GdIII ions across the double carboxylate(oxamate) bridge is responsible for the small decrease of χMT at low temperatures for 3. The dynamic (ac) magnetic properties of 2 and 3 reveal a slow magnetic relaxation with very incipient frequency-dependent χM″ signals below 6.0 K (2) and frequency-dependent χM″ peaks below 10.0 K (3) under nonzero applied dc magnetic fields, being thus new examples of field-induced single molecule magnets (SMMs).

7.
Appl Microbiol Biotechnol ; 105(9): 3601-3610, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33937931

RESUMO

The food industry has developed a wide range of products with reduced lactose to allow people with intolerance to consume dairy products. Although ß-galactosidase has extensive applications in the food, pharma, and biotechnology industries, the enzymes are high-cost catalysts, and their use makes the process costly. Immobilization is a viable strategy for enzyme retention inside a reactor, allowing its reuse and application in continuous processes. Here, we studied the immobilization of ß-galactosidase from Bacillus licheniformis in ion exchange resin. A central composite rotational design (CCRD) was proposed to evaluate the immobilization process in relation to three immobilization solution variables: offered enzyme activity, ionic strength, and pH. The conditions that maximized the response were offered enzyme activity of 953 U, 40 mM ionic strength, and pH 4.0. Subsequently, experiments were performed to provide additional stabilization for biocatalyst, using a buffer solution pH 9.0 at 25 °C for 24 h, and crosslinking with different concentrations of glutaraldehyde. The stabilization step drastically impacted the activity of the immobilized enzyme, and the reticulation with different concentrations of glutaraldehyde showed significant influence on the activity of the immobilized enzyme. In spite of substantially affecting the initial activity of the immobilized enzyme, higher reagent concentrations (3.5 g L-1) were effective for maintaining stability related to the number of cycles of the enzyme immobilized. The ß-galactosidase from Bacillus licheniformis immobilized in Duolite A568 is a promising technique to produce reduced or lactose-free dairy products, as it allows reuse of the biocatalyst, decreasing operational costs.Key Points• Immobilization of ß-galactosidase from Bacillus licheniformis in batch reactor• Influence of buffer pH and ionic concentration and offered enzyme activity on immobilization• Influence of glutaraldehyde on operational stability.


Assuntos
Bacillus licheniformis , Bacillus licheniformis/metabolismo , Indústria de Laticínios , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lactose , Temperatura , beta-Galactosidase/metabolismo
8.
Mol Pharm ; 17(7): 2612-2627, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32459098

RESUMO

Nanosystems are gaining momentum in pharmaceutical sciences because of the wide variety of possibilities for designing these systems to have specific functions. Specifically, studies of new cancer cotherapy drug-vitamin release nanosystems (DVRNs) including anticancer compounds and vitamins or vitamin derivatives have revealed encouraging results. However, the number of possible combinations of design and synthesis conditions is remarkably high. In addition, a large number of anticancer and vitamin derivatives have been already assayed, but a notably less number of cases of DVRNs were assayed as a whole (with the anticancer compound and the vitamin linked to them). Our approach combines with the perturbation theory and machine learning (PTML) model to predict the probability of obtaining an interesting DVRN by changing the anticancer compound and/or the vitamin present in a DVRN that is already tested for other anticancer compounds or vitamins that have not been tested yet as part of a DVRN. In a previous work, we built a linear PTML model useful for the design of these nanosystems. In doing so, we used information fusion (IF) techniques to carry out data enrichment of DVRN data compiled from the literature with the data for preclinical assays of vitamins from the ChEMBL database. The design features of DVRNs and the assay conditions of nanoparticles (NPs) and vitamins were included as multiplicative PT operators (PTOs) to the system, which indicates the importance of these variables. However, the previous work omitted experiments with nonlinear ML techniques and different types of PTOs such as metric-based PTOs. More importantly, the previous work does not consider the structure of the anticancer drug to be included in the new DVRNs. In this work, we are going to accomplish three main objectives (tasks). In the first task, we found a new model, alternative to the one published before, for the rational design of DVRNs using metric-based PTOs. The most accurate PTML model was the artificial neural network model, which showed values of specificity, sensitivity, and accuracy in the range of 90-95% in training and external validation series for more than 130,000 cases (DVRNs vs ChEMBL assays). Furthermore, in the second task, we used IF techniques to carry out data enrichment of our previous data set. In doing so, we constructed a new working data set of >970,000 cases with the data of preclinical assays of DVRNs, vitamins, and anticancer compounds from the ChEMBL database. All these assays have multiple continuous variables or descriptors dk and categorical variables cj (conditions of the assays) for drugs (dack, cacj), vitamins (dvk, cvj), and NPs (dnk, cnj). These data include >20,000 potential anticancer compounds with >270 protein targets (cac1), >580 assay cell organisms (cac2), and so forth. Furthermore, we include >36,000 assay vitamin derivatives in >6200 types of cells (c2vit), >120 assay organisms (c3vit), >60 assay strains (c4vit), and so forth. The enriched data set also contains >20 types of DVRNs (c5n) with 9 NP core materials (c4n), 8 synthesis methods (c7n), and so forth. We expressed all this information with PTOs and developed a qualitatively new PTML model that incorporates information of the anticancer drugs. This new model presents 96-97% of accuracy for training and external validation subsets. In the last task, we carried out a comparative study of ML and/or PTML models published and described how the models we are presenting cover the gap of knowledge in terms of drug delivery. In conclusion, we present here for the first time a multipurpose PTML model that is able to select NPs, anticancer compounds, and vitamins and their conditions of assay for DVRN design.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Vitaminas/administração & dosagem , Big Data , Simulação por Computador , Bases de Dados Factuais , Liberação Controlada de Fármacos , Modelos Lineares , Aprendizado de Máquina
9.
Inorg Chem ; 59(8): 5447-5455, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32255645

RESUMO

A series of luminescent phenoxo-bridged dinuclear TbIII complexes with tripodal ligands, 2,2'-[[(2-pyridinylmethyl)imino]di(methylene)]-bis(4-R-phenol), where R = CH3 (LCH3) (I), Cl (LCl) (II), CH3O (LCH3O) (III), COOCH3 (LCOOCH3) (IV), were prepared to probe the effect of para-substitution on the phenol ring of the ligand on the TbIII luminescence. For these TbIII complexes a complete suppression of the ligand-centered fluorescence is observed, which demonstrates an efficient ligand-to-metal energy transfer. Complex IV was found to be the one that shows the greater intensity of the emission at room temperature. The obtained quantum yields follow the trend IV > II ≫ I > III. The quantum yield for II and IV is approximately five times greater than those obtained for I and III, indicating that the LCl and LCOOCH3 are better sensitizers of the TbIII ions. These results were rationalized in terms of the variation of the energy gap between the triplet level (T1) of the ligand and the emissive 5D4 level of TbIII, due to the electron-acceptor or electron-donor properties of the substituents. The τav values are in the millisecond range for all the studied complexes and resulted independent of temperature. The Commission International d'Eclairage coordinates (CIE) for all complexes are in the green color region, being insensitive to the variation of temperature. Moreover, the color purity (CP) is ca. 90% for all complexes, being ca. 100% for IV. Thus, the introduction of electron-acceptor substituents on the ligand permitted us to improve the luminescent properties of the TbIII complexes.

10.
Mol Biol Rep ; 47(2): 1485-1489, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31820311

RESUMO

Ten microsatellite loci were developed and validated for the endangered cactus species Coleocephalocereus purpureus. The markers were obtained from sequences generated by whole genome shotgun sequencing approaches. A testing group of 36 specimens of the main population were genotyped and all described markers presented suitable outcomes to population genetic studies, showing polymorphic status for C. purpureus testing group with clean and reproducible amplification. No evidence for scoring errors, null alleles or linkage disequilibrium was detected. Number of alleles per locus ranged from 3 to 6 and expected heterozygosity ranged from 0.78 to 0.99. These new microsatellite loci are suitable to be used in future diversity and structure population studies of C. purpureus.


Assuntos
Cactaceae/genética , Espécies em Perigo de Extinção , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites/genética , Sequência de Bases , Loci Gênicos
11.
J Am Chem Soc ; 141(8): 3400-3403, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30702877

RESUMO

We report a novel bright deep-blue-emitting crystal form based on a simple cadmium coordination polymer with an impressive external photoluminescence quantum yield of 75.4(9)%.

12.
Inorg Chem ; 58(15): 10012-10018, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31318542

RESUMO

A new series of dinuclear dysprosium(III) complexes, [Dy2(LCH3)2(NO3)2(MeOH)2] (I), [Dy2(LCH3)2(NO3)2(DMF)2]·2DMF (II), [Dy2(LCl)2(NO3)2(DMF)2]·2DMF (III), and [Dy2(LCH3O)2(NO3)2(DMF)2] (IV), with 2,2'-[[(2-pyridinylmethyl)imino]di(methylene)]bis(4-R-phenol), where R = CH3, Cl, and CH3O, were investigated as potential white light emitters. All octacoordinated dysprosium(III) are phenoxo-bridged species and have a similar coordination environment. Nevertheless, I has a MeOH ligand molecule, while for II-IV a DMF ligand replaces that of MeOH. The nature of the coordinated solvent molecule plays an important role in the behavior of the thermal dependence of the Y/B (yellow/blue) emission ratio of the DyIII complexes (Y: 4F9/2 → 6H13/2, yellow and B: 4F9/2 → 6H15/2, blue transitions),, since for I the variation of this ratio is significant, while for the other DyIII complexes with DMF as ligand the ratio remains constant within experimental error. At room temperature the CIE (Commission International d'Eclairage) color coordinates for the DyIII complexes, I (0.286, 0.317), III (0.302, 0.324), and IV (0.322, 0.348) are close to the NTSC (National Television System(s) Committee) standard value for white color. Varying the temperature from 16 to 300 K the CIE coordinates for I change from the blueish to white region of the chromaticity diagram, while those of II present an inverse thermal dependence as compared to I. The CCT (Correlated Color Temperature) values at room temperature for I (8384 K), II (17235 K), and IV (5948 K) permit us to consider these complexes as candidates for white cold light emitters, the high value of II being uncommon. For I and II the CCT values vary strongly with temperature, showing a decrease with increasing temperature for I, and an increase with increasing temperature for II, thus making evident the influence on the photophysical properties of the nature of the coordinated solvent molecule in these complexes.

16.
Inorg Chem ; 54(8): 3805-14, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25831075

RESUMO

We report the crystal face indexing and molecular spatial orientation, magnetic properties, electron paramagnetic resonance (EPR) spectra, and density functional theory (DFT) calculations of two previously reported oxovanadium phosphates functionalized with Cu(II) complexes, namely, [Cu(bipy)(VO2)(PO4)]n (1) and [{Cu(phen)}2(VO2(H2O)2)(H2PO4)2 (PO4)]n (2), where bipy = 2,2'-bipyridine and phen = 1,10-phenanthroline, obtained by a new synthetic route allowing the growth of single crystals appropriate for the EPR measurements. Compounds 1 and 2 crystallize in the triclinic group P1̅ and in the orthorhombic Pccn group, respectively, containing dinuclear copper units connected by two -O-P-O- bridges in 1 and by a single -O-P-O- bridge in 2, further connected through -O-P-O-V-O- bridges. We emphasize in our work the structural aspects related to the chemical paths that determine the magnetic properties. Magnetic susceptibility data indicate bulk antiferromagnetism for both compounds, allowing to calculate J = -43.0 cm(-1) (dCu-Cu = 5.07 Å; J defined as Hex(i,j) = -J Si·Sj), considering dinuclear units for 1, and J = -1.44 cm(-1) (dCu-Cu = 3.47 Å) using the molecular field approximation for 2. The single-crystal EPR study allows evaluation of the g matrices, which provide a better understanding of the electronic structure. The absence of structure of the EPR spectra arising from the dinuclear character of the compounds allows estimation of weak additional exchange couplings |J'| > 0.3 cm(-1) for 1 (dCu-Cu = 5.54 Å) and a smaller value of |J'| ≥ 0.15 cm(-1) for 2 (dCu-Cu = 6.59 Å). DFT calculations allow evaluating two different exchange couplings for each compound, specifically, J = -36.60 cm(-1) (dCu-Cu = 5.07 Å) and J' = 0.20 cm(-1) (dCu-Cu =5.54 Å) for 1 and J = -1.10 cm(-1) (dCu-Cu =3.47 Å) and J' = 0.01 cm(-1) (dCu-Cu = 6.59 Å) for 2, this last value being in the range of the uncertainties of the calculations. Thus, these values are in good agreement with those provided by magnetic and single-crystal EPR measurements.


Assuntos
Complexos de Coordenação/química , Cobre/química , Fosfatos/química , Teoria Quântica , Vanadatos/química , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Fenômenos Magnéticos , Modelos Moleculares
17.
Foods ; 13(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38472758

RESUMO

The coffee fruit is preferably harvested at the cherry stage, with high moisture and metabolic activity, and must then undergo a drying process for better preservation of the bean and its sensory attributes. In this context, this study aimed to characterize the final quality of the Arara cultivar Arabica coffee processed using the wet method and subjected to six drying methods: three conducted at the agro-industrial establishment (fixed-bed dryer, rotary drum dryer, and combined drying) and three laboratory-scale methods (convective oven, cast-tape drying, and suspended terrace). Drying was carried out to reduce the coffee's moisture content from an initial value of 46.2% on a wet basis (w.b.) to a final average value of 11.35% (w.b.). The fruits of in natura demucilaged coffee and the processed dry coffee beans were characterized for moisture, ash content, nitrogen compounds, lipids, total titratable acidity, organic acids, sugars, and the instrumental color of the beans. The sensory profile of the Arabica coffee was evaluated by five coffee specialists using the methodology proposed by the Specialty Coffee Association (SCA), and all the coffees were classified as a specialty.

18.
J Photochem Photobiol B ; 251: 112847, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241947

RESUMO

The bovine tick Rhipicephalus microplus, a primary ectoparasite of veterinary concern, contributes significantly to disease transmission and reduced cattle productivity, resulting in substantial economic losses. The overuse of chemical acaricides has led to the emergence of resistant strains, posing a considerable challenge to veterinary medicine. Consequently, the development of alternative parasite control methods is essential to ensure livestock quality and enhance food safety worldwide. Our study introduces an innovative approach to photodynamic inactivation (PDI) of the bovine tick, harnessing natural daylight for a potential field application. Reproductive parameters (female and egg mass, egg production index, and larval hatch) were evaluated in engorged female ticks under photodynamic action using the hematoporphyrin (HP) and tetra-cationic porphyrins free-base meso-tetra-ruthenated (4-pyridyl) (RuTPyP) and its zinc(II) complex (ZnRuTPyP) as photosensitizers (PS). The results showed that there was no significant difference between the groups treated with tetra­ruthenium porphyrins and the control group. However, HP exhibits a control percentage of 97.9% at a concentration of 2.5 µmol.L-1, aligning with the expected control rates achieved by conventional chemical acaricides. Photophysical and physicochemical parameters such as the number of singlet oxygen produced and lipophilicity were discussed for each PS and related to tick control percentages. Furthermore, the interaction between HP and chitin, an important macromolecule presents in the tick's cuticle, considered as the primary target tick structure during PDI was observed by the absorption and fluorescence emission spectroscopic techniques. Therefore, the results presented here extend the potential for controlling R. microplus through photodynamic inactivation while utilizing sunlight as a source of natural irradiation.


Assuntos
Acaricidas , Porfirinas , Rhipicephalus , Animais , Feminino , Bovinos , Acaricidas/farmacologia , Rhipicephalus/fisiologia , Porfirinas/farmacologia , Reprodução
19.
J Am Mosq Control Assoc ; 40(1): 71-74, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38332553

RESUMO

Aedes albopictus is a vector of several pathogens of significant public health concern. In this situation, gravid traps have become a common surveillance tool for Aedes spp., which commonly use hay infusions as an attractant. Diverse grass infusions have been assessed to enhance the attraction to this vector mosquito. However, these studies have focused on the oviposition effect, and the attraction potential to gravid Ae. albopictus females has not been evaluated yet. Here we report the attractiveness of infusions of 4 different botanical species (Cenchrus purpureus, Cyanodon dactylon, Megathyrus maximus, Pennisetum ciliare) as baits in sticky ovitraps and autocidal gravid ovitraps (AGOs) under laboratory, semifield, and field conditions. In the laboratory, Cynodon dactylon showed attractiveness, whereas in semifield conditions, both C. dactylon and Megathyrsus maximus were similarly attractive for gravid Ae. albopictus. None of the infusions conducted with AGOs were able to lure Ae. albopictus and other species of mosquitoes in a 14-wk field experiment. Our results demonstrate the feasibility of finding more attractive infusions for Ae. albopictus females to improve the efficacy of AGO traps, but further testing of infusions in AGOs in field settings is needed.


Assuntos
Aedes , Poaceae , Feminino , Animais , Mosquitos Vetores , Oviposição , Controle de Mosquitos
20.
Inorg Chem ; 52(15): 8369-77, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23883164

RESUMO

An unusual and unique conformation of a paddle wheel type binuclear copper(II) complex containing acetate and acetamido ligands, {Cu2(µ2-O2CCH3)4}(OCNH2CH3) (1), was obtained by solvothermal synthesis. The structural characterization of this compound shows that the apical (acetamido) ligands are disposed at a 62° dihedral angle, generating a special conformation as a consequence of the synthetic method used. This conformation has not been reported in other paddle wheel copper(II) tetraacetate compounds. Electron paramagnetic resonance (EPR) spectra of powder samples of (1) were obtained at 9.5 and 33.8 GHz, while single crystal spectra were obtained at 33.8 GHz with a B0 applied in three orthogonal planes. The fit of the single crystal experimental data allowed gave g∥ = 2.345 ± 0.003, and g⊥ = 2.057 ± 0.005. The angular variation of the EPR line allows evaluation of the fine structure of (1), giving D = -0.337 ± 0.002 cm(-1) and E = -0.005 ± 0.001 cm(-1). The line width angular dependence, used together with the Anderson model and Kubo-Tomita theory, permitted the interdimer interaction to be evaluated as |J'| = (0.051 ± 0.002) cm(-1). Using the powder spectral temperature dependence it was possible to evaluate the intradinuclear exchange coupling constan J0 as -101 ± 2 cm(-1), which is considerably lower than that reported for other analogous copper(II) tetraacetate paddle wheel compounds (Cu(II)-PW), showing the remarkable effect of the conformation of the terminal ligands on the magnetic interaction.

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