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1.
Opt Lett ; 49(8): 1973-1976, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621054

RESUMO

In this Letter, we introduce a concept to produce high-resolution, highly integrable biosensing devices. Our idea exploits the highly absorbing modes in multilayered metamaterials to maximize the transverse magneto-optical Kerr effect (TMOKE). Results are discussed in the context of dielectric uniaxial (ε eff,∥ ε eff,⊥>0) and hyperbolic metamaterial (ε eff,∥ ε eff,⊥<0) regimes. For applications in gas sensing, we obtained sensitivities of S = 46.02 deg/RIU and S = 73.91 deg/RIU when considering the system working in the uniaxial and hyperbolic regimes, respectively, with figures of merit (resolution) in the order of 310 or higher. On the contrary, when considering the system for biosensing applications (incidence from an aqueous medium), we observed that the proposed mechanism can only be successfully used in the uniaxial regime, where a sensitivity of 56.87 deg/RIU was obtained.

2.
Chem Biodivers ; : e202400056, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472742

RESUMO

N-Arylenaminones are highly versatile compounds which can be synthesized in relatively simple ways. In this work we explored the synthesis of the four monosubstituted N-(4-R-phenyl)enaminones 3 a (R=NO2), 3 b (R=F), 3 c (R=H), and 3 d (R=OMe) with the goal of determining the influence of the substituents' electronic effects on tautomer stability and biological activity. These compounds were analyzed by means of Density Functional Theory calculations (DFT), to evaluate the relative stability of the possible tautomers. We found that the enaminone structure is the most stable with respect to the ketoimine and iminoenol forms. In addition, all four compounds display anticonvulsant activity, with 3 d being the one that mostly increased latency and mostly decreased the number of convulsions with respect to the control group. The suggested mechanism of action involves blockage of the voltage-dependent Na+ channels, considering that these molecules meet the structural characteristics needed to block the receptor, as is the case of the positive control molecules phenytoin (PHT) and valproic acid (VPA).

3.
J Chem Phys ; 160(7)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38380755

RESUMO

In this work, we combine the concepts of magnetic circular dichroism, nanocavities, and magneto-optical hyperbolic metamaterials (MO-HMMs) to demonstrate an approach for sensing down to a few molecules. Our proposal comprises a multilayer MO-HMM with a square, two-dimensional arrangement of nanocavities. The magnetization of the system is considered in polar configuration, i.e., in the plane of polarization and perpendicular to the plane of the multilayer structure. This allows for magneto-optical chirality to be induced through the polar magneto-optical Kerr effect, which is exhibited by reflected light from the nanostructure. Numerical analyses under the magnetization saturation condition indicate that magnetic circular dichroism peaks can be used instead of reflectance dips to monitor refractive index changes in the analyte region. Significantly, we obtained a relatively high sensitivity value of S = 40 nm/RIU for the case where refractive index changes are limited to the volume inside nanocavities, i.e., in the limit of a few molecules (or ultralow concentrations), while a very large sensitivity of S = 532 nm/RIU is calculated for the analyte region distributed along the entire superstrate layer.

4.
Med Oral Patol Oral Cir Bucal ; 29(2): e241-e247, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823295

RESUMO

BACKGROUND: Dental autotransplantation (DAT) is defined as the replacement or direct transfer of an impacted, semi-impacted or erupted tooth to a donor site, either to a post-extraction socket or to a surgically created socket within the same individual. The use of new technological advances, such as 3-D dental models based on computer-aided design, among others, have been reported to improve the success rate of DAT. Therefore, we aimed to perform a systematic review to explore the possible benefits that the use of these innovative techniques can provide when applied to DAT. MATERIAL AND METHODS: The literature search was conducted in PubMed, Scopus, and Web of Science databases following the PRISMA guidelines. The research question was: "Are computerized technological advancements a useful tool for improving the success of third molar autotransplantation technique? RESULTS: The initial literature search identified 195 articles, of which only 11 were included for qualitative analysis. All studies used 3D dental models based on computer-aided design data. Surgical guides and stereolithographic models were used by 4 and 1 study respectively. A total of 91 transplanted teeth were evaluated, out of which only 88 were considered within the parameters of clinical success (96.7%). Only 7 out of the 11 articles reported the specific autotransplanted tooth, being mandibular third molars the most prevalent autotransplanted teeth. CONCLUSIONS: Although the application of new technologies for DAT increases the success rate of this technique, further primary studies are still needed to address long-term teeth survival rates and complications. The cost and availability to implement the integration of these techniques to DAT may be a variable to consider, as this can be a limitation for some patients or for low-income countries.


Assuntos
Dente Serotino , Dente Impactado , Humanos , Dente Serotino/cirurgia , Transplante Autólogo , Dente Molar , Autoenxertos
5.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059548

RESUMO

A healthy breath is mainly composed of water, carbon dioxide, molecular nitrogen, and oxygen and it contains many species, in small quantities, which are related to the ambient atmosphere and the metabolism. The breath of a person affected by lung cancer presents a concentration of 1-propanol higher than usual. In this context, the development of specific sensors to detect 1-propanol from breath is of high interest. The amount of propanol usually detected on the breath is of few ppb; this small quantity is a handicap for a reliable diagnostic. This limitation can be overcome if the sensor is equipped with a pre-concentrator. Our studies aim to provide an efficient material playing this role. This will contribute to the development of reliable and easy to use lung cancer detectors. For this, we investigate the properties of a few hydrophobic porous materials (chabazite, silicalite-1, and dealuminated faujasite). Hydrophobic structures are used to avoid saturation of materials by the water present in the exhaled breath. Our experimental and simulation results suggest that silicalite -1 (MFI) is the most suitable structure to be used as a pre-concentrator.


Assuntos
Neoplasias Pulmonares , Zeolitas , Humanos , 1-Propanol , Adsorção , Neoplasias Pulmonares/diagnóstico , Zeolitas/química , Água/química
6.
Mar Environ Res ; 192: 106211, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37801780

RESUMO

Artisanal fisheries, although considered less harmful, can still endanger marine ecosystems, especially in areas with long-standing tradition. In Cap de Creus, where artisanal fisheries has likely occurred for centuries, the status of benthic communities in fishing grounds was poorly understood. Through collaboration with local fishers, the benthic assemblages in three artisanal fishing grounds within Cap de Creus Marine Protected Area (MPA) were studied. Using video transects recorded by a remotely operated vehicle (ROV), the diversity and distribution of species were analysed in relation to substrate type, slope, and depth. The study also assessed the impacts on these communities by examining marine litter, lost fishing gear, and the condition of gorgonian populations. The findings identified three megabenthic assemblages and revealed higher fishing pressure and impact in the Maça d'Oros area, likely due to multiple fishing guilds converging. However, the study demonstrated lower impact in MPAs compared to unprotected Mediterranean areas, highlighting the importance of coastal management.


Assuntos
Ecossistema , Pesqueiros , Mar Mediterrâneo , Conservação dos Recursos Naturais
7.
Mol Divers ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733244

RESUMO

Solving the worldwide problem of growing bacterial drug resistance will require a short-run and medium-term strategy. Structure-activity relationship (SAR) and quantitative SAR (QSAR) analyses have recently been utilized to reveal the molecular basis of the antibacterial activity and antibacterial spectrum of penicillins, the use of which is no longer solely empirical. Likewise, a more rational drug design can be achieved with cephalosporins, the largest group of ß-lactam antibiotics. The current contribution aimed to establish the molecular and physicochemical basis of the antibacterial activity of five generations of cephalosporins on methicillin-sensitive (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). With SAR and QSAR analyses, the molecular portions that provide essential and additional antibacterial activity were identified. The substitutions with greater volume and polarity on the R2 side chain of the cephem nucleus increase potency on MSSA. The best effect is produced by substitutions with polar nitrogen atoms at the alpha-carbon (Cα). Substitutions with greater volume and polarity on the R1 side chain further enhance antibacterial activity. In contrast, the effect against MRSA seems to be independent of any substitution on R2 or at the Cα, while depending on the accessory portions with greater volume and polarity on R1.

9.
Chem Commun (Camb) ; 59(45): 6845-6848, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37157896

RESUMO

Herein, we report the synthesis of novel platinum-based nanoparticles with step-pyramidal growth induced by poly(diallyldimethylammonium chloride) (PDDA). The complex stepped pyramidal shape became the central point for outstanding catalytic reduction of 4-nitrophenol, overcoming the activity of bare Pt nanoparticles. These results are valuable for the catalytic degradation of reactive molecules.

11.
Phys Chem Chem Phys ; 25(11): 8028-8042, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36876505

RESUMO

The unique properties of zeolites make them an interesting material to be used in separation processes. The possibility of tailoring some of their characteristics, like the Si/Al ratio, allows optimizing their synthesis for a given task. Concerning the adsorption of toluene by faujasites an understanding of the effect of cations is necessary to foster the elaboration of new materials, which can capture molecules with a high degree of selectivity and sensitivity. Undoubtedly, this knowledge is relevant for a wide range of applications going from the elaboration of technologies for improving the air-quality to diagnostic procedures to prevent health risks. The studies reported here using Grand Canonical Monte Carlo simulations elucidate the role of Na-cations in the adsorption of toluene by faujasites with different Si/Al ratios. They detail how the location of the cations inhibits or enhances the adsorption. The cations located at site II are shown to be those enhancing the adsorption of toluene on faujasites. Interestingly, the cations located at site III generate a hindrance at high loading. This becomes an impediment for the organization of toluene molecules inside faujasites.

12.
Opt Lett ; 48(3): 680-683, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723562

RESUMO

We demonstrate a concept for the active manipulation of radiated fields by a magnetoplasmonic half-wave dipole nanoantenna. Our idea comprises a two arms nanoantenna, made of metallic ferromagnetic cobalt-silver alloy (Co6Ag94), inspired by the analogous radio frequency half-wave dipole antenna design. Numerical results, obtained under the magnetization saturation condition, indicate a tilting of the radiated beam depending on the magnitude and sense of the magnetization of the ferromagnetic material. Significantly, we obtained tilting angles as large as ±9.7∘ around the y axis for the magnetization placed along the x or z axes, respectively. Results in this work not only open up a new, to the best of our knowledge, way to dynamically manipulate the beam steering at the chip-scale, but also contribute to unveil novel magneto-optical effects at the nanoscale.

15.
Faraday Discuss ; 242(0): 10-22, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36190123

RESUMO

The field of nanoalloys has been advancing at a rapid pace in the last two decades. Many new characterization methods and theoretical advances have produced a substantial knowledge of the nanoalloys' properties and structure. Most of the work has been limited to binary alloys. A path forward for the field will be the study of nanoalloys with three or more metals. Adding new components will produce new properties and possibly more fabrication controls. In this paper, we will discuss the challenges that will arise in multi-metallic nanoalloys. We will show that entropy and twin boundaries play a dominant role in multi-metallic alloys.

16.
J Hosp Infect ; 131: 58-69, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36216172

RESUMO

Inadequate infection control, wound care, and oral hygiene protocols in nursing homes pose challenges to residents' quality of life. Based on the outcomes from a focus group meeting and a literature search, this narrative review evaluates the current and potential roles of antiseptics within nursing home infection management procedures. We examine contemporary strategies and concerns within the management of meticillin-resistant Staphylococcus aureus (MRSA; including decolonization regimes), chronic wound care, and oral hygiene, and review the available data for the use of antiseptics, with a focus on povidone-iodine. Compared with chlorhexidine, polyhexanide, and silver, povidone-iodine has a broader spectrum of antimicrobial activity, with rapid and potent activity against MRSA and other microbes found in chronic wounds, including biofilms. As no reports of bacterial resistance or cross-resistance following exposure to povidone-iodine exist, it may be preferable for MRSA decolonization compared with mupirocin and chlorhexidine, which can lead to resistant MRSA strains. Povidone-iodine oral products have greater efficacy against oral pathogens compared with other antiseptics such as chlorhexidine mouthwash, highlighting the clinical benefit of povidone-iodine in oral care. Additionally, povidone-iodine-based products, including mouthwash, have demonstrated rapid in-vitro virucidal activity against SARS-CoV-2 and may help reduce its transmission if incorporated into nursing home coronavirus 2019 control protocols. Importantly, povidone-iodine activity is not adversely affected by organic material, such as that found in chronic wounds and the oral cavity. Povidone-iodine is a promising antiseptic agent for the management of infections in the nursing home setting, including MRSA decolonization procedures, chronic wound management, and oral care.


Assuntos
Anti-Infecciosos Locais , COVID-19 , Staphylococcus aureus Resistente à Meticilina , Humanos , Anti-Infecciosos Locais/farmacologia , Anti-Infecciosos Locais/uso terapêutico , Povidona-Iodo/farmacologia , Povidona-Iodo/uso terapêutico , Clorexidina/farmacologia , Clorexidina/uso terapêutico , Antissépticos Bucais/farmacologia , Qualidade de Vida , COVID-19/prevenção & controle , SARS-CoV-2 , Casas de Saúde
17.
Eur Ann Allergy Clin Immunol ; 55(6): 278-282, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36458479

RESUMO

Summary: Background. Kikuchi-Fujimoto Disease (KFD) or histiocytic necrotizing lymphadenitys is a rare disorder characterized by subacute necrotizing regional lymphadenopathy. It is usually presented as painful cervical nodes and associated with fever, headache, night sweats, nausea, vomiting and sore throat. Etiology of KFD is still unclear, two theories have been proposed: infections and autoimmune origin. Due to recent reports of KFD related to COVID-19 vaccination, the novelty of the mechanism of these vaccines and the immunomodulated role of both matters, a literature and adverse event databases review was carried out in order to shed light on the relationship between these two matters. Methods. A search in the Spanish and the European adverse events databases (FEDRA and Eudravigilance) was performed. Search criteria were any drug and the diagnosis "Histiocytic necrotizing lymphadenitis" according to the Medical Dictionary for Medical Activities version 25.0. All adverse events registered as June 2, 2022, were included. Results. FEDRA encompassed two KFD reports, one related to a mRNA COVID-19 vaccine. Eudravigilance included a total of 62 KFD cases, 14 of them associated to COVID-19 vaccines and eight to other vaccines. Conclusions. Pharmacovigilance is of utter importance in detecting adverse events caused by new vaccines. More research is needed to establish a final connection between KFD and COVD-19 vaccines, but due to the physiopathology of the condition, how vaccines stimulate the immune system and the high number of reported KFD cases with vaccines given its rare incidence, it is plausible to think that both entities are related.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Linfadenite Histiocítica Necrosante , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Linfadenite Histiocítica Necrosante/etiologia , Linfadenite Histiocítica Necrosante/complicações , Farmacovigilância , Vacinação/efeitos adversos
19.
Redox Biol ; 58: 102551, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36455476

RESUMO

Type 1 diabetes (T1D) involves critical metabolic disturbances that contribute to an increased cardiovascular risk. Leukocytes are key players in the onset of atherosclerosis due to their interaction with the endothelium. However, whether mitochondrial redox impairment, altered bioenergetics and abnormal autophagy in leukocytes contribute to T1D physiopathology is unclear. In this study we aimed to evaluate the bioenergetic and redox state of peripheral blood mononuclear cells (PBMCs) from T1D patients in comparison to those from healthy subjects, and to assess autophagy induction and leukocyte-endothelial interactions. T1D patients presented lower levels of fast-acting and total antioxidants in their blood, and their leukocytes produced higher amounts of total reactive oxygen species (ROS) and superoxide radical with respect to controls. Basal and ATP-linked respiration were similar in PBMCs from T1D and controls, but T1D PBMCs exhibited reduced spare respiratory capacity and a tendency toward decreased maximal respiration and reduced non-mitochondrial respiration, compared to controls. The autophagy markers P-AMPK, Beclin-1 and LC3-II/LC3-I were increased, while P62 and NBR1 were decreased in T1D PBMCs versus those from controls. Leukocytes from T1D patients displayed lower rolling velocity, higher rolling flux and more adhesion to the endothelium versus controls. Our findings show that T1D impairs mitochondrial function and promotes oxidative stress and autophagy in leukocytes, and suggest that these mechanisms contribute to an increased risk of atherosclerosis by augmenting leukocyte-endothelial interactions.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Leucócitos Mononucleares/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Leucócitos/metabolismo , Mitocôndrias/metabolismo , Autofagia , Oxirredução , Aterosclerose/metabolismo
20.
IUCrdata ; 7(Pt 10): x220947, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36405850

RESUMO

The title compound, C35H57NO3·0.25H2O, was synthesized from de-oxy-cholic acid followed by a protection, a Mitsonobu substitution, a Staudinger reduction, formation of an amide and final reduction in the lateral chain. The compound crystallizes in the P1 space group with four steroid mol-ecules and one water mol-ecule in the triclinic cell unit. The crystal structure features O-H⋯O hydrogen bonding. The crystal studied was refined as a non-merohedral twin.

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