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1.
Nature ; 629(8011): 335-340, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38658759

RESUMEN

Flexible and large-area electronics rely on thin-film transistors (TFTs) to make displays1-3, large-area image sensors4-6, microprocessors7-11, wearable healthcare patches12-15, digital microfluidics16,17 and more. Although silicon-based complementary metal-oxide-semiconductor (CMOS) chips are manufactured using several dies on a single wafer and the multi-project wafer concept enables the aggregation of various CMOS chip designs within the same die, TFT fabrication is currently lacking a fully verified, universal design approach. This increases the cost and complexity of manufacturing TFT-based flexible electronics, slowing down their integration into more mature applications and limiting the design complexity achievable by foundries. Here we show a stable and high-yield TFT platform for the fabless manufacturing of two mainstream TFT technologies, wafer-based amorphous indium-gallium-zinc oxide and panel-based low-temperature polycrystalline silicon, two key TFT technologies applicable to flexible substrates. We have designed the iconic 6502 microprocessor in both technologies as a use case to demonstrate and expand the multi-project wafer approach. Enabling the foundry model for TFTs, as an analogy of silicon CMOS technologies, can accelerate the growth and development of applications and technologies based on these devices.


Asunto(s)
Silicio , Transistores Electrónicos , Silicio/química , Electrónica/instrumentación , Indio/química , Galio/química , Óxido de Zinc/química , Diseño de Equipo , Semiconductores
2.
Proc Natl Acad Sci U S A ; 120(23): e2301852120, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37216561

RESUMEN

Cryogenic electron microscopy (cryo-EM) can reveal the molecular details of biological processes in their native, cellular environment at atomic resolution. However, few cells are sufficiently thin to permit imaging with cryo-EM. Thinning of frozen cells to <500 nm lamellae by focused-ion-beam (FIB) milling has enabled visualization of cellular structures with cryo-EM. FIB milling represents a significant advance over prior approaches because of its ease of use, scalability, and lack of large-scale sample distortions. However, the amount of damage it causes to a thinned cell section has not yet been determined. We recently described an approach for detecting and identifying single molecules in cryo-EM images of cells using 2D template matching (2DTM). 2DTM is sensitive to small differences between a molecular model (template) and the detected structure (target). Here, we use 2DTM to demonstrate that under the standard conditions used for machining lamellae of biological samples, FIB milling introduces a layer of variable damage that extends to a depth of 60 nm from each lamella surface. This layer of damage limits the recovery of information for in situ structural biology. We find that the mechanism of FIB milling damage is distinct from radiation damage during cryo-EM imaging. By accounting for both electron scattering and FIB milling damage, we estimate that FIB milling damage with current protocols will negate the potential improvements from lamella thinning beyond 90 nm.


Asunto(s)
Galio , Microscopía Electrónica , Congelación , Electrones , Microscopía por Crioelectrón/métodos , Tomografía con Microscopio Electrónico/métodos
3.
Hum Mol Genet ; 31(20): 3539-3557, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-35708503

RESUMEN

Frataxin deficiency in Friedreich's ataxia results from transcriptional downregulation of the FXN gene caused by expansion of the intronic trinucleotide guanine-adenine-adenine (GAA) repeats. We used multiple transcriptomic approaches to determine the molecular mechanism of transcription inhibition caused by long GAAs. We uncovered that transcription of FXN in patient cells is prematurely terminated upstream of the expanded repeats leading to the formation of a novel, truncated and stable RNA. This FXN early terminated transcript (FXN-ett) undergoes alternative, non-productive splicing and does not contribute to the synthesis of functional frataxin. The level the FXN-ett RNA directly correlates with the length of the longer of the two expanded GAA tracts. Targeting GAAs with antisense oligonucleotides or excision of the repeats eliminates the transcription impediment, diminishes expression of the aberrant FXN-ett, while increasing levels of FXN mRNA and frataxin. Non-productive transcription may represent a common phenomenon and attractive therapeutic target in diseases caused by repeat-mediated transcription aberrations.


Asunto(s)
Ataxia de Friedreich , Adenina , Arsenicales , Ataxia de Friedreich/genética , Ataxia de Friedreich/metabolismo , Galio , Guanina , Humanos , Proteínas de Unión a Hierro/genética , Proteínas de Unión a Hierro/metabolismo , Oligonucleótidos Antisentido , Poliadenilación/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcripción Genética , Expansión de Repetición de Trinucleótido/genética , Frataxina
4.
Anal Chem ; 96(19): 7577-7584, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696338

RESUMEN

Owing to the separation of field-effect transistor (FET) devices from sensing environments, extended-gate FET (EGFET) biosensor features high stability and low cost. Herein, a highly sensitive EGFET biosensor based on a GaN micropillar array and polycrystalline layer (GMP) was fabricated, which was prepared by using simple one-step low-temperature MOCVD growth. In order to improve the sensitivity and detection limit of EGFET biosensor, the surface area and the electrical conductivity of extended-gate electrode can be increased by the micropillar array and the polycrystalline layer, respectively. The designed GMP-EGFET biosensor was modified with l-cysteine and applied for Hg2+ detection with a low limit of detection (LOD) of 1 ng/L, a high sensitivity of -16.3 mV/lg(µg/L) and a wide linear range (1 ng/L-24.5 µg/L). In addition, the detection of Hg2+ in human urine was realized with an LOD of 10 ng/L, which was more than 30 times lower than that of reported sensors. To our knowledge, it is the first time that GMP was used as extended-gate of EGFET biosensor.


Asunto(s)
Técnicas Biosensibles , Límite de Detección , Mercurio , Humanos , Mercurio/orina , Mercurio/análisis , Transistores Electrónicos , Galio/química , Electrodos
5.
Biochem Biophys Res Commun ; 691: 149307, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38011821

RESUMEN

Many proteins and peptides can aggregate into amyloid fibrils with high-ordered and cross-ß rich structure characteristics. Amyloid deposition is a common feature of neurodegenerative diseases called amyloidosis. Various natural polyphenolic compounds such as curcumin exhibited antiamyloidogenic activities, but less researches were focused on the metal complexes of these compounds. In this study, the inhibitory effects of gallium curcumin (Ga(cur)3), indium curcumin (In(cur)3), and vanadyl curcumin (VO(cur)2) on the amyloid fibrillation of hen egg white lysozyme (HEWL) have been investigated. Moreover, the details of binding interactions of these metal complexes with HEWL have been explored. The results of fluorescence quenching analyses revealed that In(cur)3 and VO(cur)2 have much higher binding affinities than Ga(cur)3 toward HEWL. The interactions of these metal complexes were accompanied by partial conformational changes in the tertiary structure of HEWL. The kinetic curves of the fibrillation process demonstrated that In(cur)3 and VO(cur)2 have higher inhibitory effects than Ga(cur)3 on the amyloid fibrillation of HEWL. The strength of binding to HEWL is completely in accordance with inhibitory activities of these metal complexes of curcumin.


Asunto(s)
Complejos de Coordinación , Curcumina , Galio , Curcumina/farmacología , Curcumina/química , Galio/farmacología , Indio , Vanadatos , Muramidasa/metabolismo , Amiloide/metabolismo
6.
Opt Express ; 32(10): 16867-16878, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858883

RESUMEN

In this paper, a highly integrated terahertz (THz) biosensor is proposed and implemented, which pioneered the preparation of low-temperature gallium arsenide (LT-GaAs) thin film photoconductive antenna (PCA) on the sensor for direct generation and detection of THz waves, simplifying complex terahertz time-domain spectroscopy (THz-TDS) systems. A latch type metasurface is deposited in the detection region to produce a resonance absorption peak at 0.6 THz that is independent of polarisation. Microfluidics is utilised and automatic injection is incorporated to mitigate the experimental effects of hydrogen bond absorption of THz waves in aqueous-based environment. Additionally, cell damage is minimised by regulating the cell flow rate. The biosensor was utilised to detect the concentration of three distinct sizes of bacteria with successful results. The assay was executed as a proof of concept to detect two distinct types of breast cancer cells. Based on the experimental findings, it has been observed that the amplitude and blueshift of the resonance absorption peaks have the ability to identify and differentiate various cancer cell types. The findings of this study introduce a novel approach for developing microfluidic THz metasurface biosensors that possess exceptional levels of integration, sensitivity, and rapid label-free detection capabilities.


Asunto(s)
Arsenicales , Técnicas Biosensibles , Galio , Espectroscopía de Terahertz , Galio/química , Arsenicales/química , Técnicas Biosensibles/instrumentación , Espectroscopía de Terahertz/instrumentación , Humanos , Diseño de Equipo , Microfluídica/instrumentación
7.
Arch Microbiol ; 206(7): 304, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38878097

RESUMEN

The extension of multidrug-resistant strains of Staphylococcus aureus (S. aureus) is one of the main health challenges in the world, which requires serious solutions to deal with it. Combination therapies using conventional antibiotics and new antibacterial compounds that target different bacterial pathways are effective methods against resistant bacterial infections. Gallium is an iron-like metal that competes with iron for uptake into bacteria and has the potential to disrupt iron-dependent vital processes in bacteria. In this study, we explored the antibacterial effects of gallium nitrate (Ga(NO3)3) and vancomycin alone and in combination with each other on methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) using microdilution assay and checkerboard test, respectively. Then, their effect on the formation and destruction of biofilms was investigated. Finally, the amount of ROS production in the presence of these two compounds in bacteria was evaluated. The results indicated that the vancomycin/ Ga(NO3)3 combination reduced the MIC of vancomycin in the MRSA strain and had an additive effect on it. Vancomycin plus Ga(NO3)3 reduced the formation of biofilms and increased the destruction of biofilms formed in both strains, especially in the MRSA strain. ROS production was also higher in the combination of vancomycin with Ga(NO3)3 compared to vancomycin alone, especially in MRSA. Therefore, our results showed that Ga(NO3)3 enhances the antibacterial activity of vancomycin and this combination therapy can be considered as a new strategy for the treatment of MRSA infections.


Asunto(s)
Antibacterianos , Biopelículas , Galio , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Vancomicina , Galio/farmacología , Vancomicina/farmacología , Antibacterianos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Biopelículas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Sinergismo Farmacológico , Especies Reactivas de Oxígeno/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Humanos
8.
Analyst ; 149(3): 958-967, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38197472

RESUMEN

Cortisol hormone imbalances can be detected through non-invasive sweat monitoring using field-effect transistor (FET) biosensors, which provide rapid and sensitive detection. However, challenges like skin compatibility and integration with sweat collection have hindered FET biosensors as wearable sensing platforms. In this study, we present an integrated wearable sticker for real-time cortisol detection based on an extended-gate AlGaN/GaN high electron mobility transistor (HEMT) combined with a soft bottom substrate and flexible channel for sweat collection. The developed devices exhibit excellent linearity (R2 = 0.990) and a high sensitivity of 1.245 µA dec-1 for cortisol sensing from 1 nM to 100 µM in high-ionic-strength solution, with successful cortisol detection demonstrated using authentic human sweat samples. Additionally, the chip's microminiature design effectively reduces bending impact during the wearable process of traditional soft binding sweat sensors. The extendedgate structure design of the HEMT chip enhances both width-to-length ratio and active sensing area, resulting in an exceptionally low detection limit of 100 fM. Futhermore, due to GaN material's inherent stability, this device exhibits long-term stability with sustained performance within a certain attenuation range even after 60 days. These stickers possess small, lightweight, and portable features that enable real-time cortisol detection within 5 minutes through direct sweat collection. The application of this technology holds great potential in the field of personal health management, facilitating users to conveniently monitor their mental and physical conditions.


Asunto(s)
Compuestos de Aluminio , Técnicas Biosensibles , Galio , Dispositivos Electrónicos Vestibles , Humanos , Sudor/química , Hidrocortisona/análisis , Electrones , Técnicas Biosensibles/métodos
9.
Analyst ; 149(16): 4267-4275, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38904993

RESUMEN

Vertical flow assay (VFA) is an effective point-of-care (POC) diagnostic tool for widespread application. Nevertheless, the lack of multi-target detection and multi-signal readout capability still remains a challenge. Herein, a brand new VFA scheme for multi-target saliva detection based on electronic tags was proposed, where AlGaN/GaN HEMT sensors modified with different bio-receptors as electronic tags endowed the VFA with multi-target detection capability. In addition, the use of electronic tags instead of optical tags allowed the VFA to simultaneously carry out direct multi-target readouts, which ensure effective POC diagnostics for saliva analysis. Moreover, by integrating a hydrophilically optimized micro-sieve, impurities like sticky filaments, epidermal cells and other large-scale charged particles in saliva were effectively screened, which enabled the direct detection of saliva using AlGaN/GaN HEMT sensors. Glucose, urea, and cortisol were selected to verify the feasibility of the multi-target e-VFA scheme, and the results showed that the limit of detection (LOD) was as low as 100 aM. The linear response was demonstrated in the dynamic range of 100 aM to 100 µM, and the specificity, long-term stability and validity of the actual saliva test were also verified. These results demonstrated that the as-proposed e-VFA has potential for application in saliva detection for simultaneous multi-target detection, and it is expected to achieve the real-time detection of more biological targets in saliva.


Asunto(s)
Galio , Hidrocortisona , Límite de Detección , Saliva , Saliva/química , Galio/química , Humanos , Hidrocortisona/análisis , Glucosa/análisis , Urea/análisis , Urea/química , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Sistemas de Atención de Punto , Compuestos de Aluminio/química
10.
Inorg Chem ; 63(33): 15409-15420, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39116415

RESUMEN

Microorganisms of the ESKAPE group pose an enormous threat to human well-being, thus requiring a multidisciplinary approach for discovering novel drugs that are not only effective but utilize an innovative mechanism of action in order to decrease fast developing resistance. A promising but still hardly explored implementation in the "Trojan horse" antibacterial strategy has been recognized in gallium, an iron mimicry species with no known function but exerting a bacteriostatic/bactericidal effect against some representatives of the group. The study herewith focuses on the bacterium A. baumannii and its siderophore acinetobactin in its two isomeric forms depending on the acidity of the medium. By applying the powerful tools of the DFT approach, we aim to delineate those physicochemical characteristics that are of great importance for potentiating gallium's ability to compete with the native ferric cation for binding acinetobactin such as pH, solvent exposure (dielectric constant of the environment), different metal/siderophore ratios, and complex composition. Hence, the provided results not only furnish some explanation of the positive effect of three Ga3+-based anti-infectives in terms of metal cation competition but also shed light on reported in vitro and in vivo observations at a molecular level in regard to gallium's antibacterial effect against A. baumannii.


Asunto(s)
Acinetobacter baumannii , Antibacterianos , Teoría Funcional de la Densidad , Galio , Pruebas de Sensibilidad Microbiana , Galio/química , Galio/farmacología , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Oxazoles/química , Oxazoles/farmacología , Estructura Molecular , Imidazoles/química , Imidazoles/farmacología
11.
Nanotechnology ; 35(36)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38861946

RESUMEN

Breast cancer is one of the most basilisk cancers for women due to its high mortality rate which can be prevented drastically with early-stage detection. In this work, the adsorption mechanism of two volatile organic compounds that are present in the breath of breast cancer patients, 2-Methyloctane and 3, 3-Dimethylpentane, has been investigated on aluminum phosphide nanotubes (AlPNT) and gallium phosphide nanotubes (GaPNT) in order to understand their feasibility as sensor materials to diagnosis breast cancer at early stage. We have used the quantum mechanical approach by employing density functional theory using B3LYP-D3 hybrid potential for noncovalent interaction along with the LanL2DZ basis in the Gaussian 09 software package. The adsorption properties analyses suggest that GaPNT exhibits better sensing behavior as well as proclaims 12.6% greater adsorption energy for 2-Methyloctane and 9.4% greater adsorption energy for 3, 3-Dimethylpentane than AlPNT. Other structural and electric properties analyses satisfy this conclusion and suggest that GaPNT exhibits higher stability than AlPNT and could possibly be a potential candidate for developing biosensors to detect breast cancer at the preliminary stages.


Asunto(s)
Neoplasias de la Mama , Teoría Funcional de la Densidad , Nanotubos , Fosfinas , Neoplasias de la Mama/diagnóstico , Humanos , Femenino , Nanotubos/química , Fosfinas/química , Adsorción , Galio/química , Octanos/química , Compuestos Orgánicos Volátiles/análisis , Técnicas Biosensibles/métodos
12.
Phys Chem Chem Phys ; 26(25): 17817-17829, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38884203

RESUMEN

There is currently a great deal of interest in realizing localized surface plasmon resonances (LSPRs) in two distinct windows in the near-infrared (NIR) spectrum for in vivo biosensing and medical applications, the biological window (BW) I and II (BW I, 700-900 nm; BW II, 1000-1700 nm). This study aims to demonstrate that LSPRs of Ga-doped ZnO (GZO) core-silver (Ag) shell structures exhibit promising features for biological applications in the NIR BW I and II. Here, we study three different shapes for nanoshells: the core-shell nanosphere, nanorod, and nanodisk. In the calculation of the optical response of these nanoshells, an effective medium approach is first used to reduce the dielectric function of a nanoshell to that of an equivalent homogenous NP with an effective dielectric function. Then, the LSPR spectra of nanoshells are calculated using the modified long-wavelength approximation (MLWA), which corrects the polarizability of the equivalent NP as obtained by Gans theory. Through numerical investigations, we examine the impacts of the core and shell sizes of the proposed nanoshells as well as the medium refractive index on the position and line width of the plasmon resonance peaks. It is shown that the plasmon resonances of the three proposed nanoshells exhibit astonishing resonance tunability in the NIR region by varying their geometrical parameters. Specifically, the improved spectrum characteristics and tunability of its plasmon resonances make the GZO-Ag nanosphere a more viable platform for NIR applications than the spherical metal colloid. Furthermore, we demonstrate that the sensitivity and figure of merit (FOM) of the plasmon resonances may be significantly increased by using GZO-Ag nanorods and nanodisks in place of GZO-Ag nanospheres. It is found that the optical properties of the transverse plasmon resonance of the GZO-Ag nanodisk are superior to all plasmon resonances produced by the GZO-Ag nanorods and GZO-Ag nanospheres in terms of sensitivity and FOM. The FOM of the transverse plasmon mode of the GZO-Ag nanodisk is almost two orders of magnitude higher than that of the longitudinal and transverse plasmon modes of the GZO-Ag nanorod in BW I and BW II. And it is 1.5 and 2 times higher than the plasmon resonance FOM of GZO-Ag nanospheres in BW I and BW II, respectively.


Asunto(s)
Técnicas Biosensibles , Nanosferas , Nanotubos , Plata , Resonancia por Plasmón de Superficie , Óxido de Zinc , Plata/química , Nanotubos/química , Óxido de Zinc/química , Técnicas Biosensibles/métodos , Nanosferas/química , Galio/química , Rayos Infrarrojos
13.
Phys Chem Chem Phys ; 26(7): 6242-6255, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38305347

RESUMEN

The emergence of SARS-CoV-2 in 2019 led to the global COVID-19 pandemic, highlighting the urgency for developing cost-effective and non-invasive methods to detect diseases at an early stage. Human breath, rich in volatile organic compounds (VOCs), is promising for cost-effective and rapid disease detection, with specific VOCs like methanol, ethanal, butanone, acetone, and ethyl butyrate linked to COVID-19. Recent advances in biomarker detection and gas sensing with 2D materials, particularly III-As monolayers like BAs, GaAs, and AlAs, offer high sensitivity at low concentrations, providing a novel avenue for exploring their potential in detecting COVID-19 biomarkers. This article aims to examine the effects of adsorption on different properties of III-Arsenide (BAs, GaAs and AlAs) monolayers, particularly in connection with SARS-CoV-2 biomarkers. In order to examine the interaction between the monolayers and biomarkers, first-principles computations within the framework of density functional theory (DFT) are utilized. The present study involves an investigation of the modifications in the band structure, density of states (DOS), work function, electron density difference, and optical properties (reflectance and absorbance) of III-As monolayers, with the aim of assessing their viability for the detection of SARS-CoV-2 biomarkers along with interfering gases such as CO2 and H2O. It is observed that VOCs induce a notable change in the work function of GaAs which serves as an indicator of the presence of these biomarkers. However, the changes in work function are not as substantial as those for AlAs and BAs. Additionally, the chemiresistive sensitivity, optical sensitivity and recovery time of III-As are investigated. The findings suggest that the pristine GaAs monolayer displays a significant level of sensitivity and selectivity towards the SARS-CoV-2 biomarkers, rendering it a material with potential for utilization in sensing applications. Furthermore, it has been observed that the recovery time of the GaAs monolayer subsequent to its exposure to the VOC biomarkers lies within an acceptable threshold. Upon exposure to UV light, the recovery time is further reduced. The outcomes of our study indicate that GaAs monolayers exhibit considerable potential as chemiresistive, work function-based and optical sensors for the precise and discerning identification of VOCs linked to the SARS-CoV-2 virus compared to the other two III-As monolayers.


Asunto(s)
Arsenicales , COVID-19 , Galio , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Pandemias , Biomarcadores , Gases
14.
Bioorg Chem ; 152: 107736, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39208675

RESUMEN

Novel anticancer strategies reduce side effects on healthy tissues by elevating the lethal abilities of cancer cells. The development of effective particles with good bioavailability and selectivity remains problematic. For undesirable features, green chemistry is used to synthesize the best compounds, or natural-based particles are improved. Photodynamic therapy (PDT), modelled on phthalocyanines (Pcs), still delivers second-generation sensitizers which are complemented with metal ions, such as Zn2+, Al3+, or Ga3+. Gallium octacarboxyphthalocyanine hydroxide (Ga(OH)PcOC), was designed for skin cancer treatment, and was used as a pro-apoptotic and pro-oxidative agent on normal skin cell lines, fibroblasts (NHDF), and keratinocytes (HaCaT), with promising selectivity against melanoma cancer cells (Me45) in vitro. Compared to the previous reported findings, where the ZnPcOC acted on the skin cell lines at higher doses, the sensitivities to the Ga(OH)PcOC allows for an effective reduction of the sensitizer dose. The effective dose, for a novel Ga(OH)PcOC particle, was significantly reduced from 30 µM to 6 µM on Me45 cancer cells, tested using 24 h MTT viability, as well as cytometric pro-oxidative and pro-apoptotic assays. The promising photosensitizer did not reduce viability in normal fibroblasts and keratinocytes without reactive oxygen species (ROS) elevation or apoptosis induction. The improvement to the previous findings is better Ga-based photosensitizer selectivity against the cancer Me45 cells, then observed in Zn-based compounds.


Asunto(s)
Antineoplásicos , Apoptosis , Ensayos de Selección de Medicamentos Antitumorales , Galio , Indoles , Fármacos Fotosensibilizantes , Neoplasias Cutáneas , Humanos , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/síntesis química , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Galio/química , Galio/farmacología , Estructura Molecular , Indoles/química , Indoles/farmacología , Indoles/síntesis química , Isoindoles/farmacología , Isoindoles/química , Isoindoles/síntesis química , Fotoquimioterapia , Relación Dosis-Respuesta a Droga , Supervivencia Celular/efectos de los fármacos , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Hidróxidos/química , Hidróxidos/farmacología
15.
Antonie Van Leeuwenhoek ; 118(1): 3, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269546

RESUMEN

Controlling multidrug-resistant microorganisms (MRM) has a long history with the extensive and inappropriate use of antibiotics. At the cost of these drugs being scarce, new possibilities have to be explored to inhibit the growth of microorganisms. Thus, metallic compounds have shown to be promising as a viable alternative to contain pathogens resistant to conventional antimicrobials. Gallium (Ga3+) can be highlighted, which is an antimicrobial agent capable of disrupting the essential activities of microorganisms, such as metabolism, cellular respiration and DNA synthesis. It was observed that this occurs due to the similar properties between Ga3+ and iron (Fe3+), which is a fundamental ion for the correct functioning of bacterial activities. The mimetic effect performed by Ga3+ prevents iron transporters from distinguishing both ions and results in the substitution of Fe3+ for Ga3+ and in adverse metabolic disturbances in rapidly growing cells. This review focuses on analyzing the development of research involving Ga3+, elucidating the intracellular incorporation of the "Trojan Horse", summarizing the mechanism of interaction between gallium and iron and comparing the most recent and broad-spectrum studies using gallium-based compounds with antimicrobial scope.


Asunto(s)
Bacterias , Galio , Hierro , Galio/farmacología , Galio/metabolismo , Hierro/metabolismo , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Antiinfecciosos/metabolismo
16.
Ecotoxicology ; 33(2): 142-150, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38282122

RESUMEN

Gallium (Ga) is an emerging chemical pollutant chiefly associated with high-tech industries. Boron (B) alleviates the negative effects of toxic elements on plant growth. Thereby, the effects of B fertilization on Ga toxicity in rice seedlings was studied to clarify the role of iron plaque in the distribution of Ga, Fe, and B in Ga-treated rice seedlings in the presence or absence of B. Gallium exposure significantly reduced the biomass of rice seedlings. Boron deficiency induced a significant change in the distribution of B in Ga-treated rice seedlings compared with "Ga+B" treatments. Accumulation of Ga in roots, dithionite-citrate-bicarbonate (DCB) extracts, and shoots showed a dose-dependent manner from both +B and -B rice seedlings. Boron nutrition levels affect the distribution of Fe in roots, DCB extracts, and shoots, in which DCB-extractable Fe was significantly decreased from "Ga-B" treatments compared with "Ga+B" treatments. Root activity was significantly decreased in both Ga-exposed rice seedlings; however, B-deficient seedlings showed a severe reduction than +B rice seedlings. These results reveal that Fe plaque might be a temporary sink for B accumulation when plants are grown with proper B, wherein the re-utilization of DCB-extractable B stored in Fe plaque is mandatory for plant growth under B deficiency. Correlation analysis revealed that B deficiency decreased the root activity of Ga-exposed rice seedlings by reducing DCB-extractable Fe and increasing DCB-extractable Ga in Fe plaque. This study enhances our understanding of how B nutritional levels affect Ga toxicity in rice plants.


Asunto(s)
Galio , Oryza , Contaminantes del Suelo , Plantones , Hierro , Boro/toxicidad , Boro/análisis , Galio/farmacología , Raíces de Plantas , Citratos/farmacología , Ácido Cítrico/farmacología , Contaminantes del Suelo/toxicidad
17.
Luminescence ; 39(5): e4773, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38757733

RESUMEN

Two Schiff base probes (S1 and S2) were prepared and synthesized by incorporating thienopyrimidine into salicylaldehyde or 3-ethoxysalicylaldehyde individually, with the aim of detecting Ga3+ and Pd2+ sequentially. Upon chelation with Ga3+, S1 and S2 exhibited fluorescence enhancement in DMSO/H2O buffer. Both S1-Ga3+ and S2-Ga3+ were quenched by Pd2+. The limit of detection for S1 in response to Ga3+ and Pd2+ was 2.86 × 10-7 and 4.4 × 10-9 M, respectively. For S2, the limit of detection for Ga3+ and Pd2+ was 4.15 × 10-8 and 3.0 × 10-9 M, respectively. Furthermore, the complexation ratios of both S1 and S2 with Ga3+ and Pd2+ were determined to be 1:2 through Job's plots, ESI-MS analysis, and theoretical calculations. Two molecular logic gates were constructed, leveraging the response behaviors of S1 and S2. Moreover, the potential utility of S1 and S2 for monitoring Ga3+ and Pd2+ in domestic water was verified.


Asunto(s)
Colorantes Fluorescentes , Galio , Paladio , Pirimidinas , Bases de Schiff , Bases de Schiff/química , Paladio/química , Pirimidinas/química , Pirimidinas/análisis , Galio/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Espectrometría de Fluorescencia , Estructura Molecular
18.
Luminescence ; 39(10): e4907, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39350335

RESUMEN

As one of the fundamental physical quantities, temperature is extremely important in various fields. In order to study the temperature sensing characteristics of dual-emitting center phosphors, Bi3+-doped and Bi3+/Sm3+-doped Sr2Ga2GeO7 phosphors were synthesized by high-temperature solid-phase method. Under 312 nm excitation, the Sr2Ga2GeO7:Bi3+ phosphor exhibits a blue broadband emission corresponding to the 3P1 → 1S0 transition of Bi3+ ions. By testing the temperature change spectrum of phosphors, it was found that Bi3+ exhibited strong thermal sensitivity. However, due to the fact that single ion doped phosphors are easily affected by other factors when applied to the field of temperature sensing, based on the thermal sensitivity of Bi3+, Sm3+ with low temperature sensitivity was selected as the co-doped ion, and it was found that the two ions had different thermal quenching characteristics when the temperature change spectrum was tested. Using the temperature detection method based on the fluorescence intensity ratio (FIR) of the dual emission centers, it was found that the best absolute sensitivity Sa was 3.125% K-1 and the maximum relative sensitivity Sr was 1.275% K-1 in the range of 303-423 K. These results show that Sr2Ga2GeO7:Bi3+/Sm3+ phosphors have broad application prospects in the field of optical temperature sensing.


Asunto(s)
Galio , Luminiscencia , Sustancias Luminiscentes , Samario , Estroncio , Temperatura , Estroncio/química , Samario/química , Sustancias Luminiscentes/química , Sustancias Luminiscentes/síntesis química , Galio/química , Bismuto/química , Germanio/química , Mediciones Luminiscentes
19.
Luminescence ; 39(5): e4762, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38698695

RESUMEN

Broadband near-infrared (NIR) spectroscopy has gained significant attention due to its versatile application in various fields. In the realm of NIR phosphors, Fe3+ ion is an excellent activator known for its nontoxic and harmless nature. In this study, we prepared an Fe3+-activated SrGa12O19 (SGO) NIR phosphor and analyzed its phase and luminescence properties. Upon excitation at 326 nm, the SGO:Fe3+ phosphor exhibited a broadband emission in the range 700-1000 nm, peaking at 816 nm. The optical band gap of SGO:Fe3+ was evaluated. To enhance the long-lasting phosphorescence, an oxygen vacancy-rich SGO:Fe3+ (VO-SGO:Fe3+) sample was prepared for activation. Interestingly, the increase in the oxygen-vacancy concentration indeed contributed to the activation of persistent luminescence of Fe3+ ions. The VO-SGO:Fe3+ sample has a long duration and high charge storage capacity, allowing it to perform efficiently in various applications. This work provides the foundation for further design of Cr3+-free PersL phosphors with efficient NIR PersL.


Asunto(s)
Luminiscencia , Sustancias Luminiscentes , Oxígeno , Oxígeno/química , Sustancias Luminiscentes/química , Estroncio/química , Mediciones Luminiscentes , Compuestos Férricos/química , Galio/química , Hierro/química , Espectroscopía Infrarroja Corta
20.
Lasers Med Sci ; 39(1): 48, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38279075

RESUMEN

This study aimed to investigate the effects of 0.6% hyaluronic acid (HA) gel on the healing process and postoperative pain levels after diode laser-assisted labial frenectomy in pediatric patients. Ninety-six pediatric patients (females, 50 and males, 46) aged 8-14 years were randomly divided into four groups as follows: (1) conventional frenectomy with 0.6% topically administered HA (CFH, n = 24); (2) conventional frenectomy with placebo gel (CFP, n = 24); (3) frenectomy performed by diode laser with 0.6% topically administered HA (DLH, n = 24); and (4) frenectomy performed by diode laser with placebo gel (DLP, n = 24). HA application was continued for 1 week thrice daily after the frenectomy. Visual analog scale forms were collected from patients 1 week after the operation. In addition, the plaque index, gingival index, periodontal probing depth, and keratinized tissue width and thickness were recorded. This process was repeated 1 and 3 months after the first visit. The DLH group revealed significant differences in the probing depth, bleeding on probing, keratinized gingiva width, and attached gingiva width according to dual comparisons of the initial, first, and third-month values (p = 0.010, p = 0.007, p<0.001, and p = 0.001, respectively). Significant differences were observed between the CFP and CFH groups according to the initial and initial third-month values with regard to the bleeding on probing (p=0.019 and p = 0.019, respectively). The attached gingival thickness revealed significant differences between the CFP and CFH groups for the initial and initial-third-month comparisons (p = 0.005 and p = 0.007, respectively). The mean values of the initial and initial-third-month differences were significantly higher in the CFH group than those in the CFP group. HA- and laser-assisted labial frenectomies revealed better outcomes in terms of the probing depth, attached gingiva width, keratinized gingiva width, healing process, and postoperative comfort.


Asunto(s)
Arsenicales , Galio , Ácido Hialurónico , Láseres de Semiconductores , Masculino , Femenino , Humanos , Niño , Láseres de Semiconductores/uso terapéutico , Indio , Frenectomía Oral , Encía
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