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1.
Biol Res ; 57(1): 30, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760850

RESUMO

BACKGROUND: Mutations in isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2), are present in most gliomas. IDH1 mutation is an important prognostic marker in glioma. However, its regulatory mechanism in glioma remains incompletely understood. RESULTS: miR-182-5p expression was increased within IDH1-mutant glioma specimens according to TCGA, CGGA, and online dataset GSE119740, as well as collected clinical samples. (R)-2-hydroxyglutarate ((R)-2HG) treatment up-regulated the expression of miR-182-5p, enhanced glioma cell proliferation, and suppressed apoptosis; miR-182-5p inhibition partially eliminated the oncogenic effects of R-2HG upon glioma cells. By direct binding to Cyclin Dependent Kinase Inhibitor 2 C (CDKN2C) 3'UTR, miR-182-5p inhibited CDKN2C expression. Regarding cellular functions, CDKN2C knockdown promoted R-2HG-treated glioma cell viability, suppressed apoptosis, and relieved cell cycle arrest. Furthermore, CDKN2C knockdown partially attenuated the effects of miR-182-5p inhibition on cell phenotypes. Moreover, CDKN2C knockdown exerted opposite effects on cell cycle check point and apoptosis markers to those of miR-182-5p inhibition; also, CDKN2C knockdown partially attenuated the functions of miR-182-5p inhibition in cell cycle check point and apoptosis markers. The engineered CS-NPs (antagomir-182-5p) effectively encapsulated and delivered antagomir-182-5p, enhancing anti-tumor efficacy in vivo, indicating the therapeutic potential of CS-NPs(antagomir-182-5p) in targeting the miR-182-5p/CDKN2C axis against R-2HG-driven oncogenesis in mice models. CONCLUSIONS: These insights highlight the potential of CS-NPs(antagomir-182-5p) to target the miR-182-5p/CDKN2C axis, offering a promising therapeutic avenue against R-2HG's oncogenic influence to glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Isocitrato Desidrogenase , MicroRNAs , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Glioma/genética , Glioma/metabolismo , Animais , Camundongos , Xenoenxertos , Transplante de Neoplasias , Neoplasias Encefálicas/genética , MicroRNAs/metabolismo
2.
J Forensic Sci ; 69(4): 1198-1211, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38691107

RESUMO

The illegal drug market is constantly evolving, with new drugs being created and existing ones being modified. Adulterants are often added to the mix, and the primary substance may be secretly replaced by a new one. Once-known tablets can now be vastly different from what they are sold as, all due to the pursuit of profit and evasion of current drug regulations. These alterations in drug composition pose a threat to society, as their effects are still not well understood. Therefore, it is crucial for police intelligence and public health development to obtain the chemical profiles of illicit drugs. This study presents the chemical fingerprinting of ecstasy tablets seized in the state of Rio de Janeiro (Brazil) between 2012 and 2021. The tablet samples were weighed, extracted, diluted with methanol, and acidified before analysis using gas chromatography high-resolution mass spectrometry and attenuated total reflection Fourier transform infrared spectroscopy. The major constituents found were MDMA and clobenzorex, with fewer occurrences of MDA, MDEA, and 2C-B. The results also indicate that the occurrence of mega-events in the study location impacted the chemical fingerprints of ecstasy. A total of 27 combinations of cutting agents, including caffeine, ephedrine, and anesthetics, were identified. Samples composed of clobenzorex were observed throughout the evaluated period in areas near highways, suggesting that this product is mainly used by truck drivers. These findings can help police intelligence units anticipate the behavior of the illicit market during major events, identify traffic routes, and support public health initiatives.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Alucinógenos , Drogas Ilícitas , N-Metil-3,4-Metilenodioxianfetamina , Brasil , N-Metil-3,4-Metilenodioxianfetamina/análise , Humanos , Drogas Ilícitas/química , Drogas Ilícitas/análise , Alucinógenos/análise , Alucinógenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Contaminação de Medicamentos , Tráfico de Drogas
3.
J Photochem Photobiol B ; 256: 112943, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788534

RESUMO

With the rapid development of nanotechnology, various functional nanomaterials have shown exciting potential in biomedical areas such as drug delivery, antitumor, and antibacterial therapy. These nanomaterials improve the stability and selectivity of loaded drugs, reduce drug-induced side effects, realize controlled and targeted drug release, and increase therapeutic efficacy. The increased resistance to antifungal microbicides in medical practice and their side effects stimulate interest in new therapies, such as Photodynamic Therapy (PDT), which do not generate resistance in microorganisms and effectively control the pathology. The present study aimed to evaluate, in vitro, the efficacy of photodynamic therapy on Candida albicans using 1,9-Dimethyl-Methylene Blue (DMMB) as photosensitizer, red LED (λ630), and nanoencapsulation of DMMB (RL-NPs/DMMB) using rhamnolipids produced by Pseudomonas aeruginosa to evaluate if there is better performance of DMMB + RL particles compared to DMMB alone via the characterization of DMMB + RL and colony forming count. The tests were carried out across six experimental groups (Control, DMMB, RL-NPs, RL-NPs/DMMB, PDT and PDT + RL-NPs/DMMB) using in the groups with nanoparticles, DMMB (750 ng/mL) encapsulated with rhamnolipids in a 1:1 ratio, the light source consisted of a prototype built with a set of red LEDs with an energy density of 20 J/cm2. The results showed that applying PDT combined with encapsulation (RL-NPs/DMMB) was a more practical approach to inhibit Candida albicans (2 log reduction) than conventional applications, with a possible clinical application protocol.


Assuntos
Candida albicans , Glicolipídeos , Azul de Metileno , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Pseudomonas aeruginosa , Candida albicans/efeitos dos fármacos , Glicolipídeos/química , Glicolipídeos/farmacologia , Azul de Metileno/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanopartículas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/farmacologia , Composição de Medicamentos
4.
Heliyon ; 10(3): e25604, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356535

RESUMO

Gentamicin (GEN), a widely used broad-spectrum antibiotic, faces challenges amid the global emergency of antimicrobial resistance. This study aimed to explore the synergistic effects of zinc oxide nanoparticles (ZnO NPs) in combination with GEN on the bactericidal activity against various bacterial strains. Results showed ZnO NPs with MICs ranging from 0.002 to 1.5 µg/mL, while the precursor salt displayed a MIC range of 48.75-1560 µg/mL. Chitosan (CS)-capped ZnO NPs exhibited even lower MICs than their uncapped counterparts, with the CS-capped synthesized ZnO NPs demonstrating the lowest values. Minimal bactericidal concentrations (MBC) aligned with MIC trends. Combinations of CS-capped synthesized ZnO NPs and GEN proved highly effective, inhibiting bacterial growth at significantly lower concentrations than GEN or ZnO NPs alone. This phenomenon may be attributed to the conformation of CS on the ZnO NPs' surface, enhancing the positive particle surface charge. This possibly facilitates a more effective interaction between ZnO NPs and microorganisms, leading to increased accumulation of zinc and GEN within bacterial cells and an overproduction of reactive oxygen species (ROS). It's crucial to note that, while this study did not specifically involve resistant strains, its primary focus remains on enhancing the overall antimicrobial activity of gentamicin. The research aims to contribute to addressing the global challenge of antimicrobial resistance, recognizing the urgent need for effective strategies to combat this critical issue. The findings, particularly the observed synergy between ZnO NPs and GEN, hold significant implications for repositioning the first-line antibiotic GEN.

5.
Nanomaterials (Basel) ; 14(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38251108

RESUMO

This work presents the effect of CeO2 nanoparticles (CeO2-NPs) on Cu-50Ni-5Al alloys on morphological, microstructural, degradation, and electrochemical behavior at high temperatures. The samples obtained by mechanical alloying and spark plasma sintering were exposed to a molten eutectic mixture of Li2CO3-K2CO3 for 504 h. The degradation of the materials was analyzed using gravimetry measurements and electrochemical impedance spectroscopy. Different characterization techniques, such as X-ray diffraction and scanning electron microscopy, were used to investigate the phase composition, parameter lattice, and microstructure of Cu-Ni-Al alloys reinforced with CeO2-NPs. The hardness of the composite was also examined using the Vickers hardness test. Gravimetry measurements revealed that the sample with 1 wt.% CeO2-NPs presented the best response to degradation with a less drastic mass variation. Impedance analysis also revealed that by adding 1 wt.% CeO2-NPs, the impedance modulus increased, which is related to a lower porosity of the oxide film or a thicker oxide layer. The microhardness also significantly increased, incorporating 1 wt.% CeO2-NPs, which reduced with higher CeO2-NPs content, which is possibly associated with a more uniform distribution using 1 wt.% CeO2-NPs in the Cu-Ni-Al matrix that avoided the aggregation phenomenon.

6.
Biol. Res ; 572024.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564045

RESUMO

Background Mutations in isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2), are present in most gliomas. IDH1 mutation is an important prognostic marker in glioma. However, its regulatory mechanism in glioma remains incompletely understood. Results miR-182-5p expression was increased within IDH1-mutant glioma specimens according to TCGA, CGGA, and online dataset GSE119740, as well as collected clinical samples. (R)-2-hydroxyglutarate ((R)-2HG) treatment up-regulated the expression of miR-182-5p, enhanced glioma cell proliferation, and suppressed apoptosis; miR-182-5p inhibition partially eliminated the oncogenic effects of R-2HG upon glioma cells. By direct binding to Cyclin Dependent Kinase Inhibitor 2 C (CDKN2C) 3'UTR, miR-182-5p inhibited CDKN2C expression. Regarding cellular functions, CDKN2C knockdown promoted R-2HG-treated glioma cell viability, suppressed apoptosis, and relieved cell cycle arrest. Furthermore, CDKN2C knockdown partially attenuated the effects of miR-182-5p inhibition on cell phenotypes. Moreover, CDKN2C knockdown exerted opposite effects on cell cycle check point and apoptosis markers to those of miR-182-5p inhibition; also, CDKN2C knockdown partially attenuated the functions of miR-182-5p inhibition in cell cycle check point and apoptosis markers. The engineered CS-NPs (antagomir-182-5p) effectively encapsulated and delivered antagomir-182-5p, enhancing anti-tumor efficacy in vivo, indicating the therapeutic potential of CS-NPs(antagomir-182-5p) in targeting the miR-182-5p/CDKN2C axis against R-2HG-driven oncogenesis in mice models. Conclusions These insights highlight the potential of CS-NPs(antagomir-182-5p) to target the miR-182-5p/CDKN2C axis, offering a promising therapeutic avenue against R-2HG's oncogenic influence to glioma.

7.
Phys Med Biol ; 68(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37852274

RESUMO

Metallic nanoparticles, such as gold (Au, Z = 79) and silver (Ag, Z = 47) nanoparticles (AuNPs and AgNPs, respectively), possess strong surface plasmonic resonance (SPR) and high atomic number, which makes them ideal candidates for enhancing dosimeter sensitivity. In this study, we have inserted different mass percentages (from 0 to 0.015 wt%) of AuNPs into a gelatinous Fricke-xylenol-orange (FXO-f) gel matrix and irradiated it with doses ranging from 2 to 32 Gy, using a source of x-ray of low energy with an effective energy of 42 keV. Optical absorption increased significantly; sensitivity gains of up to 50% were achieved for the FXO-f gel matrix containing 0.011 wt% AuNPs. To elucidate the mechanism underlying this increased sensitivity, we also evaluated FXO-f gel matrixes containing AgNPs. AgNPs insertion into the FXO-f gel matrix did not enhance sensitivity, which suggested that the AgNPs plasmonic absorption band and the FXO-f gel matrix absorption band at 441 nm overlapped, to increase absorption even after the gel matrix was irradiated. To visualize the dose distribution, we recorded optical tomography and acquired 3D reconstruction maps. In addition, we analyzed the dose enhancement factor (DEF) by using magnetic resonance images. AuNPs insertion into the FXO-f gel matrix resulted in a DEF gain of 1.37, associated with the photoelectric effect originating from the increased number of free radicals.


Assuntos
Ouro , Nanopartículas Metálicas , Radiometria/métodos , Imageamento por Ressonância Magnética
8.
Pharmaceutics ; 15(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37765166

RESUMO

The increasing demand for non-invasive biocompatible materials in biomedical applications, driven by accidents and diseases like cancer, has led to the development of sustainable biomaterials. Here, we report the synthesis of four block formulations using polycaprolactone (PCL), polylactic acid (PLA), and zinc oxide nanoparticles (ZnO-NPs) for subdermal tissue regeneration. Characterization by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) confirmed the composition of the composites. Additionally, the interaction of ZnO-NPs mainly occurred with the C=O groups of PCL occurring at 1724 cm-1, which disappears for F4, as evidenced in the FT-IR analysis. Likewise, this interaction evidenced the decrease in the crystallinity of the composites as they act as crosslinking points between the polymer backbones, inducing gaps between them and weakening the strength of the intermolecular bonds. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses confirmed that the ZnO-NPs bind to the carbonyl groups of the polymer, acting as weak points in the polymer backbone from where the different fragmentations occur. Scanning electron microscopy (SEM) showed that the increase in ZnO-NPs facilitated a more compact surface due to the excellent dispersion and homogeneous accumulation between the polymeric chains, facilitating this morphology. The in vivo studies using the nanocomposites demonstrated the degradation/resorption of the blocks in a ZnO-NP-dependant mode. After degradation, collagen fibers (Type I), blood vessels, and inflammatory cells continue the resorption of the implanted material. The results reported here demonstrate the relevance and potential impact of the ZnO-NP-based scaffolds in soft tissue regeneration.

9.
Braz J Microbiol ; 54(3): 1341-1350, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37400611

RESUMO

The subtropical fruit known as the loquat is prized for both its flavour and its health benefits. The perishable nature of loquat makes it vulnerable to several biotic and abiotic stressors. During the previous growing season (March-April 2021), loquat in Islamabad showed signs of fruit rot. Loquat fruits bearing fruit rot symptoms were collected, and the pathogen that was causing the disease isolated and identified using its morphology, microscopic visualisation, and rRNA sequence. The pathogen that was isolated was identified as Fusarium oxysporum. Green synthesized metallic iron oxide nanoparticles (Fe2O3 NPs) were employed to treat fruit rot disease. Iron oxide nanoparticles were synthesized using a leaf extract of the Calotropis procera. Characterization of NPs was performed by different modern techniques. Fourier transform infrared spectroscopy (FTIR) determined the existence of stabilizing and reducing compounds like phenol, carbonyl compounds, and nitro compounds, on the surface of Fe2O3 NPs. X-ray diffraction (XRD) explained the crystalline nature and average size (~49 nm) of Fe2O3 NPs. Energy dispersive X-ray (EDX) exhibited Fe and O peaks, and scanning electron microscopy (SEM) confirmed the smaller size and spherical shape of Fe2O3 NPs. Following both in vitro and in vivo approaches, the antifungal potential of Fe2O3 NPs was determined, at different concentrations. The results of both in vitro and in vivo analyses depicted that the maximum fungal growth inhibition was observed at concentration of 1.0 mg/mL of Fe2O3 NPs. Successful mycelial growth inhibition and significantly reduced disease incidence suggest the future application of Fe2O3 NPs as bio fungicides to control fruit rot disease of loquat.


Assuntos
Eriobotrya , Fusarium , Nanopartículas Metálicas , Nanopartículas , Frutas/química , Nanopartículas Metálicas/química , Paquistão , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Difração de Raios X , Antibacterianos/farmacologia
10.
Int J Mol Sci ; 24(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37511161

RESUMO

This study takes a step in understanding the physiological implications of the nanosecond pulsed electric field (nsPEF) by integrating molecular dynamics simulations and machine learning techniques. nsPEF, a state-of-the-art technology, uses high-voltage electric field pulses with a nanosecond duration to modulate cellular activity. This investigation reveals a relatively new and underexplored phenomenon: protein-mediated electroporation. Our research focused on the voltage-sensing domain (VSD) of the NaV1.5 sodium cardiac channel in response to nsPEF stimulation. We scrutinized the VSD structures that form pores and thereby contribute to the physical chemistry that governs the defibrillation effect of nsPEF. To do so, we conducted a comprehensive analysis involving the clustering of 142 replicas simulated for 50 ns under nsPEF stimuli. We subsequently pinpointed the representative structures of each cluster and computed the free energy between them. We find that the selected VSD of NaV1.5 forms pores under nsPEF stimulation, but in a way that significant differs from the traditional VSD opening. This study not only extends our understanding of nsPEF and its interaction with protein channels but also adds a new effect to further study.


Assuntos
Eletricidade , Eletroporação , Eletroporação/métodos , Terapia com Eletroporação , Coração
11.
Chemosphere ; 339: 139628, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37524267

RESUMO

In the present research work, the photocatalytic evaluation of NiTiO3 nanoparticles immobilized on glass plates by the spin-coating procedure was carried out in the degradation of the recalcitrant herbicide 2,6-dichlorobenzamide (BAM). The concentrations of Ni employed to synthesize NiTiO3 nanoparticles were 1 wt% (1TESNi) and 2 wt% (2TESNi). The stability of coatings was evaluated by several washings and thermal treatments, which were verified by UV-vis analyses. The morphology of the coatings was studied by scanning electron microscopy (SEM-EDS). The coatings displayed thickness values of 1.35 and 2.56 µm for TiO2 and 1TESNi, respectively. The crystalline phases of the coatings were analyzed by X-ray diffraction (XRD), confirming the presence of NiTiO3 and other phases related to TiO2. The bandgap of 1TESNi, compared with the bare TiO2, was reduced from 2.96 to 2.40 eV as a consequence of Ni addition. The TiO2, 1TESNi and 2TESNi coatings were evaluated in the photodegradation of BAM using visible-light for 240 min. The highest effectiveness was displayed by the 1TESNi coating, obtaining degradation of 92.56% after 240 min. Also, the photocatalytic efficiency of the 1TESNi coating was only reduced 1.99% after 3 reuse cycles in the BAM degradation. The scavenger tests revealed that the main oxidizing species involved in the reaction were the •OH- and •O2- radicals. The 1TESNi coating showed the highest photocatalytic efficiency because of its absorption in the visible-light region, valuable surface area and electronic charge separation. Thus, these advantageous features guarantee that NiTiO3 coatings are an efficient method for degrading recalcitrant herbicides from drinking water using a practical way to recover and reuse photocatalysts.


Assuntos
Água Potável , Herbicidas , Herbicidas/química , Catálise , Titânio/química
12.
Food Chem Toxicol ; 179: 113945, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451599

RESUMO

Iron oxide nanoparticles present superparamagnetic properties that enable their application in various areas, including drug delivery at specific locations in the organism. Silver nanoparticles have potent antimicrobial effects. Although the combination of Fe3O4-NPs and Ag-NPs in one hybrid nanostructure (Fe3O4@Ag-NPs) demonstrated promising targeted biomedical applications, their toxicological effects are unknown and need to be assessed. Caenorhabditis elegans is a promising model for nanotoxicological analysis, as it allows an initial screening of new substances. After exposure to Fe3O4-NPs, Ag-NPs and Fe3O4@Ag-NPs, we observed that hybrid NPs reduced the C. elegans survival and reproduction. Higher concentrations of Fe3O4@Ag-NPs caused an increase in cell apoptosis in the germline and a decrease in egg laying, which was associated with a decrease in worm swimming movements and abnormalities in the cholinergic neurons. Fe3O4@Ag-NPs caused an increase in reactive oxygen species, along with activation of DAF-16 transcription factor. A higher expression of the target genes GST-4::GFP and SOD-3::GFP were evidenced, which suggests the activation of the antioxidant system. Our results indicate the reprotoxicity caused by high levels of Fe3O4@Ag-NPs, as well as cholinergic neurotoxicity and activation of the antioxidant system in C. elegans, suggesting that high concentrations of these nanomaterials can be harmful to living organisms.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Animais , Caenorhabditis elegans , Nanopartículas Metálicas/química , Prata/química , Antioxidantes/farmacologia , Nanopartículas/toxicidade
13.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);99(3): 296-301, May-June 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1440463

RESUMO

Abstract Objective To verify the performance of the Net Promoter Score (NPS) as a tool to assess parental satisfaction in pediatric intensive care units (PICUs). Methods The authors conducted an observational cross-sectional multicenter study in the PICUs of 5 hospitals in Brazil. Eligible participants were all parents or legal guardians of PICU-admitted children, aged 18 years or over. The NPS was administered together with the EMpowerment of PArents in THe Intensive Care (EMPATHIC-30), used as the gold standard, and a sociodemographic questionnaire. For analysis, the results were dichotomized into values greater than or equal to the median of the tests. The associations between the 2 tools were evaluated and the distribution of their results was compared. Results The parents or legal guardians of 78 PICU-admitted children were interviewed. Of the respondents, 85% were women and 62% were in a private hospital. The median NPS was 10 (IQR, 10-10), and the median EMPATHIC-30 score was 5.7 (IQR, 5.4-5.9). Compared with the gold standard, the NPS had a sensitivity of 100% at all cutoff points, except at cutoff 10, where the sensitivity was slightly lower (97.5%). As for specificity, NPS performance was poorer, with values ranging from 0% (NPS ≥ 5) to 47.4% (NPS = 10). Conclusions NPS proved to be a sensitive tool to assess parental satisfaction, but with poor ability to identify dissatisfied users in the sample.

14.
Nanomaterials (Basel) ; 13(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37177070

RESUMO

Hybrid films for applications in organic electronics from NiFe2O4 nanoparticles (NPs) in poly(3,4 ethylene dioxythiophene), poly(4-styrenesulfonate) (PEDOT:PSS), and poly(methyl methacrylate) (PMMA) were fabricated by the spin-coating technique. The films were characterized by infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and energy-dispersive spectroscopy to subsequently determine their optical parameters. The electronic transport of the hybrid films was determined in bulk heterojunction devices. The presence of NiFe2O4 NPs reinforces mechanical properties and increases transmittance in the hybrid films; the PEDOT:PSS-NiFe2O4 NPs film is the one that has a maximum stress of 28 MPa and a Knoop hardness of 0.103, while the PMMA-NiFe2O4 NPs film has the highest transmittance of (87%). The Tauc band gap is in the range of 3.78-3.9 eV, and the Urbach energy is in the range of 0.24-0.33 eV. Regarding electrical behavior, the main effect is exerted by the matrix, although the current carried is of the same order of magnitude for the two devices: glass/ITO/polymer-NiFe2O4 NPs/Ag. NiFe2O4 NPs enhance the mechanical, optical, and electrical behavior of the hybrid films and can be used as semi-transparent anodes and as active layers.

15.
ACS Appl Mater Interfaces ; 15(22): 26496-26509, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37219485

RESUMO

Curcumin (CUR) is one natural bioactive compound acknowledged for diverse therapeutic activities, but its use is hindered by its poor bioavailability, fast metabolism, and susceptibility to pH variations and light exposure. Thus, the encapsulation in poly(lactic-co-glycolic acid), or PLGA, has been successfully used to protect and enhance CUR absorption in the organism, making CUR-loaded PLGA nanoparticles (NPs) promising drug delivery systems. However, few studies have focused beyond CUR bioavailability, on the environmental variables involved in the encapsulation process, and whether they could help obtain NPs of superior performance. Our study evaluated pH (3.0 or 7.0), temperature (15 or 35 °C), light exposure, and inert atmosphere (N2) incidence in the encapsulation of CUR. The best outcome was at pH 3.0, 15 °C, without light incidence, and without N2 usage. This best nanoformulation showed NP size, zeta potential, and encapsulation efficiency (EE) of 297 nm, -21 mV, and 72%, respectively. Moreover, the CUR in vitro release at pH values 5.5 and 7.4 suggested different potential applications for these NPs, one of which was demonstrated by the effective inhibition of multiple bacteria (i.e., Gram-negative, Gram-positive, and multi-resistant) in the minimal inhibition concentration assay. Besides, statistical analyses confirmed a significant impact of temperature on the NP size; in addition, temperature, light, and N2 affected the EE of CUR. Thus, the selection and control of process variables resulted in higher CUR encapsulation and customizable outcomes, ultimately enabling more economical processes and providing future scale-up guidelines.


Assuntos
Curcumina , Nanopartículas , Curcumina/farmacologia , Curcumina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Glicóis , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Tamanho da Partícula , Portadores de Fármacos/química
16.
Environ Res ; 228: 115860, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030405

RESUMO

The immobilization of TiO2-SiO2 (TSO) materials on seed mats stands as a practical way to help the germination and early growth of tomato plants (Solanum Lycopersicum). Mesoporous materials are functionalized with triethanolamine (TEA) and loaded with the biocide molecule of carvacrol (CAR). The effect of CAR on the parameters of germination percentage, germination time, root, shoot length, and chlorophyll content of seeds and/or tomato seedlings are investigated. The germination experiments were carried out using seed mats coated with the TSO materials, also TSO powdered materials were put directly on the tomato seeds to study their effect on germination. Direct deposition of TSO composites achieved the complete germination and longer shoots due to the cooperative interactions among nanomaterials, carvacrol, and the tomato seed. However, the handling of the seeds and the detrimental effect of powder in the germination system made difficult the application with agricultural purposes. The plastic seed mats provide a practical system with lower germination, but more homogenous growth of root/shoot is possible. Surprisingly, in this methodology the carvacrol presents a detrimental effect on germination due to less interaction with the seeds. The handling of seeds and recover of the nanomaterials and its reuse are advantages of the plastic seed mats, which together with less wastage of seeds suggest a potential use in agriculture. The as-synthetized TSO NPs, together with the functionalization of triethanolamine and carvacrol used to promote the health germination of the seeds, allows the control of the time for seed germination, germination %, and length for the root/shoot of seed tomato germination. The immobilization of mesoporous materials results in an alternative to help the germination and early growth of agricultural plants searching to avoid the lixiviation of nanomaterials to the environment.


Assuntos
Germinação , Solanum lycopersicum , Dióxido de Silício , Sementes
17.
Rev. Hosp. Ital. B. Aires (2004) ; 43(1): 7-11, mar. 2023. ilus, tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1434097

RESUMO

Introducción: el NPS (Net Promoter Score) es un indicador que se utiliza en los programas de experiencia del cliente para medir la satisfacción de dicho público objetivo y su lealtad. Nuestra finalidad fue consolidar el NPS por primera vez en una prepaga de un hospital de alta complejidad de Buenos Aires (PS-HIBA) en busca de establecer un indicador objetivo desde la perspectiva del cliente. Métodos: se realizó un estudio observacional analítico, de corte transversal. Se incluyeron en el estudio los datos obtenidos a partir de las respuestas de los afiliados al PS-HIBA. Resultados: se consolidó el primer indicador NPS del PS-HIBA: 22 puntos. Se visualizaron los tres perfiles de clientes, obteniendo un 45,7% promotores, 22,3% detractores y 32% pasivos o neutros. Complementariamente se identificaron los motivos de dichas calificaciones; las tres principales fueron: la problemática de accesibilidad a los turnos, la atención y los profesionales valorados positivamente. Conclusión: este estudio aporta un indicador objetivo, que facilita un lenguaje común en la organización y una comparación con el mercado desde la mirada del cliente. El NPS, como sistema, busca impulsar la construcción de una cultura centrada en el cliente, con el fin de mejorar su lealtad y permitir una retroalimentación donde se logra tener presente la voz del cliente, e identificar, priorizar y abordar los problemas percibidos. Nos permite establecer los lineamientos de oportunidades de mejora desde la perspectiva de los pacientes. (AU)


Introduction: the NPS (Net Promoter Score) is an indicator used in customer experience programs to measure the satisfaction of said target audience and their loyalty. Our purpose was to send the survey and consolidate the NPS for the first time in a high complexity prepaid hospital in Buenos Aires (PS-HIBA) in search of an objective indicator from the customer's perspective. Methods: an analytical, cross-sectional observational study was carried out. Data obtained from members' responses to the PS-HIBA were included in the study. Results: the first NPS indicator of PS-HIBA was consolidated: 22 points. The three customer profiles were displayed, obtaining 45.7% promoters, 22.3% detractors and 32% passive or neutral. Complementarily, the reasons for these qualifications were identified, being the three main ones: the problem of accessibility to medical appointments, the medical attention and the professionals valued positively. Conclusion: this study provides an objective indicator which facilitates a common language in the organization and a comparison with the market from the customer's point of view.The NPS as a system seeks to promote the construction of a customer-focused culture, in order to improve their loyalty and allow feedback. Thus, it is possible to keep the customer's voice in mind, identify, prioritize and address the perceived problems. It allows us to establish the guidelines for opportunities to improve from the patients' perspective. (AU)


Assuntos
Humanos , Cobertura de Serviços de Saúde , Satisfação do Paciente , Indicadores de Qualidade em Assistência à Saúde , Instituições Privadas de Saúde , Argentina , Estudos Transversais , Inquéritos e Questionários , Benchmarking , Medidas de Resultados Relatados pelo Paciente
18.
Nanomaterials (Basel) ; 13(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36770386

RESUMO

Although several studies assess the biological effects of micro and titanium dioxide nanoparticles (TiO2 NPs), the literature shows controversial results regarding their effect on bone cell behavior. Studies on the effects of nanoparticles on mammalian cells on two-dimensional (2D) cell cultures display several disadvantages, such as changes in cell morphology, function, and metabolism and fewer cell-cell contacts. This highlights the need to explore the effects of TiO2 NPs in more complex 3D environments, to better mimic the bone microenvironment. This study aims to compare the differentiation and mineralized matrix production of human osteoblasts SAOS-2 in a monolayer or 3D models after exposure to different concentrations of TiO2 NPs. Nanoparticles were characterized, and their internalization and effects on the SAOS-2 monolayer and 3D spheroid cells were evaluated with morphological analysis. The mineralization of human osteoblasts upon exposure to TiO2 NPs was evaluated by alizarin red staining, demonstrating a dose-dependent increase in mineralized matrix in human primary osteoblasts and SAOS-2 both in the monolayer and 3D models. Furthermore, our results reveal that, after high exposure to TiO2 NPs, the dose-dependent increase in the bone mineralized matrix in the 3D cells model is higher than in the 2D culture, showing a promising model to test the effect on bone osteointegration.

19.
Nanomaterials (Basel) ; 13(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36770395

RESUMO

The development of nanomaterials has drawn considerable attention in nanomedicine to advance cancer diagnosis and treatment over the last decades. Gold nanorods (GNRs) and magnetic nanoparticles (MNPs) have been known as commonly used nanostructures in biomedical applications due to their attractive optical properties and superparamagnetic (SP) behaviors, respectively. In this study, we proposed a simple combination of plasmonic and SP properties into hybrid NPs of citrate-coated manganese ferrite (Ci-MnFe2O4) and cetyltrimethylammonium bromide-coated GNRs (CTAB-GNRs). In this regard, two different samples were prepared: the first was composed of Ci-MnFe2O4 (0.4 wt%), and the second contained hybrid NPs of Ci-MnFe2O4 (0.4 wt%) and CTAB-GNRs (0.04 wt%). Characterization measurements such as UV-Visible spectroscopy and transmission electron microscopy (TEM) revealed electrostatic interactions caused by the opposing surface charges of hybrid NPs, which resulted in the formation of small nanoclusters. The performance of the two samples was investigated using magneto-motive ultrasound imaging (MMUS). The sample containing Ci-MnFe2O4_CTAB-GNRs demonstrated a displacement nearly two-fold greater than just using Ci-MnFe2O4; therefore, enhancing MMUS image contrast. Furthermore, the preliminary potential of these hybrid NPs was also examined in magnetic hyperthermia (MH) and photoacoustic imaging (PAI) modalities. Lastly, these hybrid NPs demonstrated high stability and an absence of aggregation in water and phosphate buffer solution (PBS) medium. Thus, Ci-MnFe2O4_CTAB-GNRs hybrid NPs can be considered as a potential contrast agent in MMUS and PAI and a heat generator in MH.

20.
J Mech Behav Biomed Mater ; 140: 105687, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36780815

RESUMO

This study evaluated the influence of the TiO2 nanoparticles (NPs) on the mechanical and chemical performance of Sn and Sn-Ag alloys. The XRD (X-ray diffraction) and HR-TEM (high resolution-transmission electron microscopy) methods were used to characterize the NPs synthesized by the sol-gel microwave process. The chemical composition of the alloys was Sn, Sn+3TiO2 NPs, Sn-5Ag+1.5TiO2 NPs, Sn-10Ag, and Sn-10Ag+3TiO2 NPs, obtained from an experimental factorial design (EFD). A statistical model was used to determine the mechanical and chemical properties, showing the Vickers hardness response surface, tensile strength, wear, and corrosion resistance. The wear and corrosion tests for the various alloy compositions were performed using human artificial saliva solution. The results indicated that the Sn-10Ag+3TiO2 NPs exhibited the highest mechanical performance due to their increased hardness (380 HV), tensile strength (370 N), and wear resistance (0.34 × 10-3 mm3 Nm-1); in all the cases, the inclusion of TiO2 NPs enhanced the corrosion resistance of the alloys. According to the American Dental Association (ADA), Sn-10Ag+3TiO2 NPs alloy could be classified as a possible type IV restorative material.


Assuntos
Ligas , Titânio , Humanos , Ligas/química , Corrosão , Titânio/química , Dureza , Difração de Raios X , Teste de Materiais
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