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1.
Sci Rep ; 14(1): 18014, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39097612

RESUMEN

Cerium oxide nanoparticles are known for their antibacterial effects resulting from Ce3+ to Ce4+ conversion. Application of such cerium oxide nanoparticles in dentistry has been previously considered but limited due to deterioration of mechanical properties. Hence, this study aimed to examine mesoporous silica (MCM-41) coated with cerium oxide nanoparticles and evaluate the antibacterial effects and mechanical properties when applied to dental composite resin. Cerium oxide nanoparticles were coated on the MCM-41 surface using the sol-gel method by adding cerium oxide nanoparticle precursor to the MCM-41 dispersion. The samples were tested for antibacterial activity against Streptococcus mutans via CFU and MTT assays. The mechanical properties were assessed by flexural strength and depth of cure according to ISO 4049. Data were analyzed using a t-test, one-way ANOVA, and Tukey's post-hoc test (p = 0.05). The experimental group showed significantly increased antibacterial properties compared to the control groups (p < 0.005). The flexural strength exhibited a decreasing trend as the amount of cerium oxide nanoparticle-coated MCM-41 increased. However, the flexural strength and depth of cure values of the silane group met the ISO 4049 standard. Antibacterial properties increased with increasing amounts of cerium oxide nanoparticles. Although the mechanical properties decreased, silane treatment overcame this drawback. Hence, the cerium oxide nanoparticles coated on MCM-41 may be used for dental resin composite.


Asunto(s)
Antibacterianos , Cerio , Resinas Compuestas , Nanopartículas , Dióxido de Silicio , Streptococcus mutans , Cerio/química , Cerio/farmacología , Dióxido de Silicio/química , Antibacterianos/farmacología , Antibacterianos/química , Resinas Compuestas/química , Resinas Compuestas/farmacología , Streptococcus mutans/efectos de los fármacos , Nanopartículas/química , Resinas Acrílicas/química , Ensayo de Materiales , Poliuretanos/química , Poliuretanos/farmacología , Resistencia Flexional , Porosidad
2.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39000193

RESUMEN

The aim of this special issue is to show the advances in the different applications that inorganic materials based on silica have had in recent years [...].


Asunto(s)
Dióxido de Silicio , Dióxido de Silicio/química , Catálisis , Porosidad , Adsorción
3.
Int J Nanomedicine ; 19: 7123-7136, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055375

RESUMEN

Background: Drug therapy for eye diseases has been limited by multiple protective mechanisms of the eye, which can be improved using well-designed drug delivery systems. Mesoporous silica nanoparticles (MSNs) had been used in many studies as carriers of therapeutic agents for ocular diseases treatment. However, no studies have focused on ocular biosafety. Considering that MSNs containing tetrasulfur bonds have unique advantages and have drawn increasing attention in drug delivery systems, it is necessary to explore the ocular biosafety of tetrasulfur bonds before their widespread application as ophthalmic drug carriers. Methods: In this study, hollow mesoporous silica nanoparticles (HMSNs) with different tetrasulfur bond contents were prepared and characterized. The ocular biosafety of HMSN-E was evaluated in vitro on the three selected ocular cell lines, including corneal epithelial cells, lens epithelial cells and retinal endothelial cells (HREC), and in vivo by using topical eye drops and intravitreal injections. Results: In cellular experiments, HMSNs caused obvious S content-dependent cytotoxic effect. HMSNs with the highest tetrasulfur bond content (HMSN-E), showed the highest cytotoxicity among all the HMSNs, and HREC was the most vulnerable cell to HMSN-E. It was shown that HMSN-E could react with intracellular GSH to generate H2S and decrease intracellular GSH concentration. Treatment of HREC with HMSN-E increased intracellular ROS, decreased mitochondrial membrane potential, and induced cell cycle arrest at the G1/S checkpoint, finally caused apoptosis and necrosis of HREC. Topical eye drops of HMSN-E could cause corneal damage. The intravitreal injection of HMSN-E could induce inflammation in the vitreum and ganglion cell layers, resulting in vitreous opacities and retinal abnormalities. Conclusion: The incorporation of tetrasulfur bonds into HMSN can have toxic effects on ocular tissues. Therefore, when mesoporous silica nanocarriers are designed for ophthalmic pharmaceuticals, the ocular toxicity of the tetrasulfur bonds should be considered.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Humanos , Animales , Nanopartículas/química , Dióxido de Silicio/química , Dióxido de Silicio/toxicidad , Línea Celular , Porosidad , Portadores de Fármacos/química , Apoptosis/efectos de los fármacos , Conejos , Supervivencia Celular/efectos de los fármacos , Ojo/efectos de los fármacos , Soluciones Oftálmicas/química , Soluciones Oftálmicas/farmacología , Compuestos de Organosilicio/química , Compuestos de Organosilicio/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Células Epiteliales/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Inyecciones Intravítreas
4.
Luminescence ; 39(7): e4832, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39031322

RESUMEN

The aim of this research is to investigate novel compositions of oxyfluoride glasses doped with Neodymium (Nd3+) rare earth ions in the visible spectrum. This area has not been extensively studied in the existing literature, so it is vital to understand the favorable photoluminescence characteristics within this part of the electromagnetic spectrum. Therefore, we synthesized and characterized SiO2-PbO-PbF2 (SPF) doped with 1% neodymium (Nd3+) ions glasses. Spectroscopic analyses, based on Judd-Ofelt theory, were conducted on absorption spectra. These analyses enabled to determine absorption cross-sections, transition probabilities, and Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 for the different transition. Additionally, we calculated various radiative properties, such as branching ratios, integrated cross-sections, radiative lifetimes, emission cross-section, optical gain, and the multicolor behavior (chromaticity coordinates, CIE diagram) under different excitation wavelengths. The results suggest promising prospects for using these oxyfluoride silicate glasses doped with Nd3+ as a fluorophore, potentially for lasing materials around 630-nm emission and in other photonic applications.


Asunto(s)
Vidrio , Neodimio , Silicatos , Dióxido de Silicio , Neodimio/química , Vidrio/química , Silicatos/química , Dióxido de Silicio/química , Fluoruros/química , Plomo/química , Óxidos/química , Fenómenos Ópticos , Luminiscencia , Color
5.
Drug Deliv ; 31(1): 2381340, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39041383

RESUMEN

Pulmonary delivery and formulation of biologics are among the more complex and growing scientific topics in drug delivery. We herein developed a dry powder formulation using disordered mesoporous silica particles (MSP) as the sole excipient and lysozyme, the most abundant antimicrobial proteins in the airways, as model protein. The MSP had the optimal size for lung deposition (2.43 ± 0.13 µm). A maximum lysozyme loading capacity (0.35 mg/mg) was achieved in 150 mM PBS, which was seven times greater than that in water. After washing and freeze-drying, we obtained a dry powder consisting of spherical, non-aggregated particles, free from residual buffer, or unabsorbed lysozyme. The presence of lysozyme was confirmed by TGA and FT-IR, while N2 adsorption/desorption and SAXS analysis indicate that the protein is confined within the internal mesoporous structure. The dry powder exhibited excellent aerodynamic performance (fine particle fraction <5 µm of 70.32%). Lysozyme was released in simulated lung fluid in a sustained kinetics and maintaining high enzymatic activity (71-91%), whereas LYS-MSP were shown to degrade into aggregated nanoparticulate microstructures, reaching almost complete dissolution (93%) within 24 h. MSPs were nontoxic to in vitro lung epithelium. The study demonstrates disordered MSP as viable carriers to successfully deliver protein to the lungs, with high deposition and retained activity.


Asunto(s)
Pulmón , Muramidasa , Tamaño de la Partícula , Polvos , Dióxido de Silicio , Dióxido de Silicio/química , Muramidasa/administración & dosificación , Muramidasa/química , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Porosidad , Polvos/química , Portadores de Fármacos/química , Administración por Inhalación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Humanos , Excipientes/química , Animales , Química Farmacéutica/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Liofilización
6.
Parasite ; 31: 41, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39052011

RESUMEN

Bed bugs are considered a major public health problem in industrialized countries. Usually, bed bug infestations are managed using a combination of physical and chemical methods. In recent years, new strategies for bed bug control have emerged, particularly the use of dusts like diatomaceous earth and silicon dioxide. However, in Europe, the use of silicon dioxide is restricted to professional, while diatomaceous earth can be harmful to the lungs. This study aimed to assess bed bug mortality rates associated with Sommières earth, green clay, talc, and sodium bicarbonate compared to silicon dioxide and diatomaceous earth from a pest management company, diatomaceous earth for litter conditioner, and diatomaceous earth from a supermarket. We tested permanent exposure, short exposure, horizontal transfer and repellent effect on two bed bug colonies. Sommières earth demonstrated efficacy ranging from 75% to 100% in permanent and short exposures, similar to the efficacy of diatomaceous earth from the pest management company. On the contrary, diatomaceous earth for litter conditioner and diatomaceous earth from a supermarket, green clay, talc, and sodium bicarbonate were found to be ineffective. This study demonstrates, for the first time, the efficacy of Sommières earth against bed bugs, but also highlights the variability in efficacy of diatomaceous earths on bed bugs depending on their quality.


Title: Lutte contre les punaises de lit avec des poudres : comparaison de l'efficacité du dioxyde de silicium, de la terre de diatomée et de la terre de Sommières. Abstract: Les punaises de lit sont considérées comme un problème de santé publique majeur dans les pays industrialisés. Habituellement, les infestations de punaises de lit sont gérées en utilisant une combinaison de méthodes physiques et chimiques. Ces dernières années, de nouvelles stratégies de lutte contre les punaises de lit ont vu le jour, notamment l'utilisation de poudres comme la terre de diatomées et le dioxyde de silicium. Cependant, en Europe, l'usage du dioxyde de silicium est réservé aux professionnels tandis que la terre de diatomées peut être nocive pour les poumons. Cette étude visait à évaluer les taux de mortalité des punaises de lit associés à la terre de Sommières, à l'argile verte, au talc et au bicarbonate de sodium par rapport au dioxyde de silicium, à la terre de diatomées d'une entreprise de lutte antiparasitaire, à la terre de diatomées pour conditionneur de litière et à la terre de diatomées d'un supermarché. Nous avons testé l'exposition permanente, l'exposition courte, le transfert horizontal et l'effet répulsif sur deux colonies de punaises de lit. La terre de Sommières a démontré une efficacité allant de 75% à 100% en exposition permanente et courte, similaire à l'efficacité de la terre de diatomées d'une entreprise de lutte antiparasitaire. Au contraire, la terre de diatomées pour conditionneur de litière et la terre de diatomées d'un supermarché, l'argile verte, le talc et le bicarbonate de sodium se sont révélés inefficaces. Cette étude démontre, pour la première fois, l'efficacité de la terre de Sommières contre les punaises de lit mais met également en évidence la variabilité de l'efficacité des terres de diatomées sur les punaises de lit en fonction de leur qualité.


Asunto(s)
Chinches , Tierra de Diatomeas , Control de Insectos , Dióxido de Silicio , Talco , Animales , Chinches/efectos de los fármacos , Control de Insectos/métodos , Polvo/análisis , Arcilla/química , Bicarbonato de Sodio/farmacología
7.
Biosensors (Basel) ; 14(7)2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-39056595

RESUMEN

Gold nanoparticles (AuNPs) play a vital role in biotechnology, medicine, and diagnostics due to their unique optical properties. Their conjugation with antibodies, antigens, proteins, or nucleic acids enables precise targeting and enhances biosensing capabilities. Functionalized AuNPs, however, may experience reduced stability, leading to aggregation or loss of functionality, especially in complex biological environments. Additionally, they can show non-specific binding to unintended targets, impairing assay specificity. Within this work, citrate-stabilized and silica-coated AuNPs (GNPs and SiGNPs, respectively) have been coated using N,N-dimethylacrylamide-based copolymers to increase their stability and enable their functionalization with biomolecules. AuNP stability after modification has been assessed by a combination of techniques including spectrophotometric characterization, nanoparticle tracking analysis, transmission electron microscopy and functional microarray tests. Two different copolymers were identified to provide a stable coating of AuNPs while enabling further modification through click chemistry reactions, due to the presence of azide groups in the polymers. Following this experimental design, AuNPs decorated with ssDNA and streptavidin were synthesized and successfully used in a biological assay. In conclusion, a functionalization scheme for AuNPs has been developed that offers ease of modification, often requiring single steps and short incubation time. The obtained functionalized AuNPs offer considerable flexibility, as the functionalization protocol can be personalized to match requirements of multiple assays.


Asunto(s)
Oro , Nanopartículas del Metal , Polímeros , Oro/química , Nanopartículas del Metal/química , Polímeros/química , Técnicas Biosensibles , Bioensayo , Acrilamidas/química , Dióxido de Silicio/química , Estreptavidina/química
8.
Biosensors (Basel) ; 14(7)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39056602

RESUMEN

Mesoporous silica nanoparticles (MSNs) exhibit highly beneficial characteristics for devising efficient biosensors for different analytes. Their unique properties, such as capabilities for stable covalent binding to recognition groups (e.g., antibodies or aptamers) and sensing surfaces, open a plethora of opportunities for biosensor construction. In addition, their structured porosity offers capabilities for entrapping signaling molecules (dyes or electroactive species), which could be released efficiently in response to a desired analyte for effective optical or electrochemical detection. This work offers an overview of recent research studies (in the last five years) that contain MSNs in their optical and electrochemical sensing platforms for the detection of cancer biomarkers, classified by cancer type. In addition, this study provides an overview of cancer biomarkers, as well as electrochemical and optical detection methods in general.


Asunto(s)
Biomarcadores de Tumor , Técnicas Biosensibles , Nanopartículas , Dióxido de Silicio , Dióxido de Silicio/química , Biomarcadores de Tumor/análisis , Nanopartículas/química , Humanos , Porosidad , Neoplasias/diagnóstico , Técnicas Electroquímicas
9.
Biomed Environ Sci ; 37(6): 617-627, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38988112

RESUMEN

Objective: The aim of this study was to explore the role and mechanism of ferroptosis in SiO 2-induced cardiac injury using a mouse model. Methods: Male C57BL/6 mice were intratracheally instilled with SiO 2 to create a silicosis model. Ferrostatin-1 (Fer-1) and deferoxamine (DFO) were used to suppress ferroptosis. Serum biomarkers, oxidative stress markers, histopathology, iron content, and the expression of ferroptosis-related proteins were assessed. Results: SiO 2 altered serum cardiac injury biomarkers, oxidative stress, iron accumulation, and ferroptosis markers in myocardial tissue. Fer-1 and DFO reduced lipid peroxidation and iron overload, and alleviated SiO 2-induced mitochondrial damage and myocardial injury. SiO 2 inhibited Nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes, while Fer-1 more potently reactivated Nrf2 compared to DFO. Conclusion: Iron overload-induced ferroptosis contributes to SiO 2-induced cardiac injury. Targeting ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO 2 cardiotoxicity, potentially via modulation of the Nrf2 pathway.


Asunto(s)
Modelos Animales de Enfermedad , Ferroptosis , Sobrecarga de Hierro , Ratones Endogámicos C57BL , Miocitos Cardíacos , Dióxido de Silicio , Silicosis , Animales , Ferroptosis/efectos de los fármacos , Masculino , Ratones , Sobrecarga de Hierro/metabolismo , Dióxido de Silicio/toxicidad , Silicosis/metabolismo , Silicosis/tratamiento farmacológico , Silicosis/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Deferoxamina/farmacología , Fenilendiaminas/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo/efectos de los fármacos , Hierro/metabolismo , Ciclohexilaminas/farmacología
10.
ACS Appl Mater Interfaces ; 16(28): 36168-36193, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38954488

RESUMEN

In the intricate landscape of Traumatic Brain Injury (TBI), the management of TBI remains a challenging task due to the extremely complex pathophysiological conditions and excessive release of reactive oxygen species (ROS) at the injury site and the limited regenerative capacities of the central nervous system (CNS). Existing pharmaceutical interventions are limited in their ability to efficiently cross the blood-brain barrier (BBB) and expeditiously target areas of brain inflammation. In response to these challenges herein, we designed novel mussel inspired polydopamine (PDA)-coated mesoporous silica nanoparticles (PDA-AMSNs) with excellent antioxidative ability to deliver a new potential therapeutic GSK-3ß inhibitor lead small molecule abbreviated as Neuro Chemical Modulator (NCM) at the TBI site using a neuroprotective peptide hydrogel (PANAP). PDA-AMSNs loaded with NCM (i.e., PDA-AMSN-D) into the matrix of PANAP were injected into the damaged area in an in vivo cryogenic brain injury model (CBI). This approach is specifically built while keeping the logic AND gate circuit as the primary focus. Where NCM and PDA-AMSNs act as two input signals and neurological functional recovery as a single output. Therapeutically, PDA-AMSN-D significantly decreased infarct volume, enhanced neurogenesis, rejuvenated BBB senescence, and accelerated neurological function recovery in a CBI.


Asunto(s)
Antioxidantes , Bivalvos , Lesiones Traumáticas del Encéfalo , Indoles , Nanocompuestos , Neurogénesis , Estrés Oxidativo , Polímeros , Indoles/química , Indoles/farmacología , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/metabolismo , Polímeros/química , Polímeros/farmacología , Animales , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/química , Antioxidantes/farmacología , Nanocompuestos/química , Bivalvos/química , Neurogénesis/efectos de los fármacos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Dióxido de Silicio/química , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Masculino
11.
ACS Appl Mater Interfaces ; 16(28): 35912-35924, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38976770

RESUMEN

The extracellular matrix (ECM) shapes the stem cell fate during differentiation by exerting relevant biophysical cues. However, the mechanism of stem cell fate decisions in response to ECM-backed complex biophysical cues has not been fully understood due to the lack of versatile ECMs. Here, we designed two versatile ECMs using colloidal self-assembly technology to probe the mechanisms of their effects on mechanotransduction and stem cell fate regulation. Binary colloidal crystals (BCC) with a hexagonally close-packed structure, composed of silica (5 µm) and polystyrene (0.4 µm) particles as well as a polydimethylsiloxane-embedded BCC (BCCP), were fabricated. They have defined surface chemistry, roughness, stiffness, ion release, and protein adsorption properties, which can modulate the cell adhesion, proliferation, and differentiation of human adipose-derived stem cells (hASCs). On the BCC, hASCs preferred osteogenesis at an early stage but showed a higher tendency toward adipogenesis at later stages. In contrast, the results of BCCP diverged from those of BCC, suggesting a unique regulation of ECM-dependent mechanotransduction. The BCC-mediated cell adhesion reduced the size of the focal adhesion complex, accompanying an ordered spatial organization and cytoskeletal rearrangement. This morphological restriction led to the modulation of mechanosensitive transcription factors, such as c-FOS, the enrichment of transcripts in specific signaling pathways such as PI3K/AKT, and the activation of the Hippo signaling pathway. Epigenetic analyses showed changes in histone modifications across different substrates, suggesting that chromatin remodeling participated in BCC-mediated mechanotransduction. This study demonstrates that BCCs are versatile artificial ECMs that can regulate human stem cells' fate through unique biological signaling, which is beneficial in biomaterial design and stem cell engineering.


Asunto(s)
Diferenciación Celular , Coloides , Epigénesis Genética , Células Madre Mesenquimatosas , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Coloides/química , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacología , Adhesión Celular/efectos de los fármacos , Mecanotransducción Celular/efectos de los fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Dióxido de Silicio/química , Poliestirenos/química , Proliferación Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos
12.
Astrobiology ; 24(7): 734-753, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38985714

RESUMEN

Jotun springs in Svalbard, Norway, is a rare warm environment in the Arctic that actively forms travertine. In this study, we assessed the microbial ecology of Jotun's active (aquatic) spring and dry spring transects. We evaluated the microbial preservation potential and mode, as well as the astrobiological relevance of the travertines to marginal carbonates mapped at Jezero Crater on Mars (the Mars 2020 landing site). Our results revealed that microbial communities exhibited spatial dynamics controlled by temperature, fluid availability, and geochemistry. Amorphous carbonates and silica precipitated within biofilm and on the surface of filamentous microorganisms. The water discharged at the source is warm, with near neutral pH, and undersaturated in silica. Hence, silicification possibly occurred through cooling, dehydration, and partially by a microbial presence or activities that promote silica precipitation. CO2 degassing and possible microbial contributions induced calcite precipitation and travertine formation. Jotun revealed that warm systems that are not very productive in carbonate formation may still produce significant carbonate buildups and provide settings favorable for fossilization through silicification and calcification. Our findings suggest that the potential for amorphous silica precipitation may be essential for Jezero Crater's marginal carbonates because it significantly increases the preservation potential of putative martian organisms.


Asunto(s)
Exobiología , Manantiales de Aguas Termales , Regiones Árticas , Manantiales de Aguas Termales/microbiología , Manantiales de Aguas Termales/química , Marte , Dióxido de Silicio/química , Svalbard , Carbonatos/química , Carbonatos/análisis , Microbiota , Temperatura , Biopelículas
13.
Rom J Morphol Embryol ; 65(2): 173-184, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39020531

RESUMEN

Over the last decades, silica nanoparticles (SiNPs) have been studied for their applications in biomedicine as an alternative used for conventional diagnostics and treatments. Since their properties can be modified and adjusted for the desired use, they have many different potential applications in medicine: they can be used in diagnosis because of their ability to be loaded with dyes and their increased selectivity and sensitivity, which can improve the quality of the diagnostic process. SiNPs can be functionalized by targeting ligands or molecules to detect certain cellular processes or biomarkers with better precision. Targeted delivery is another fundamental use of SiNPs. They could be used as drug delivery systems (DDS) since their structure allows the loading of therapeutic agents or other compounds, and studies have demonstrated their biocompatibility. When SiNPs are used as DDS, the drug's toxicity and the off-target effects are reduced significantly, and they can be used to treat conditions like cancer and neurological diseases and even aid in regenerative processes, such as wound healing or bone repair. However, safety concerns must be considered before SiNPs can be used extensively in clinical practice because NPs can cause toxicity in certain conditions and accumulate at undesired locations. Therefore, an overview of the potential applications that SiNPs could have in medicine, as well as their safety concerns, will be covered in this review paper.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanopartículas , Dióxido de Silicio , Humanos , Nanopartículas/química , Nanopartículas/uso terapéutico , Dióxido de Silicio/química , Sistemas de Liberación de Medicamentos/métodos , Animales
14.
Water Sci Technol ; 90(1): 61-74, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39007307

RESUMEN

Wastewater reuse is one of the crucial water resources in Egypt due to the ongoing need to increase water resources and close the supply-demand gap. In this study, a new coagulant has been investigated before sand filters as an advanced wastewater treatment method. The sand filter pilot was run at a hydraulic loading rate of 0.75 m/h and two different dosages of three coagulants (Alum, FeCl3, and Ferrate VI) were selected using the jar tests. The sand filter without coagulant removed 12% of BOD5 and 70% of turbidity. Applying in-line coagulation before the sand filter provided effluents with better quality, especially for turbidity, organics, and microorganisms. Ferrate provided the highest removal of turbidity (90%) and BOD5 (93%) at very low dosages and lower costs compared with other coagulants, however, it adversely impacted both conductivity and dissolved solids. A significant effect on reducing bacteria was obtained with 40.0 mg/L of alum. According to the study's findings, the ferrate coagulant enhanced the sand filter's performance producing effluents with high quality, enabling it to meet strict water reuse regulations as well as aquatic environmental and health preservations.


Asunto(s)
Filtración , Hierro , Aguas Residuales , Purificación del Agua , Filtración/métodos , Hierro/química , Aguas Residuales/química , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos , Arena/química , Dióxido de Silicio/química
15.
Nat Commun ; 15(1): 5824, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992009

RESUMEN

Access to clean water, hygiene, and sanitation is becoming an increasingly pressing global demand, particularly owing to rapid population growth and urbanization. Phytoremediation utilizes a highly conserved phytochelatin in plants, which captures hazardous heavy metal ions from aquatic environments and sequesters them in vacuoles. Herein, we report the design of phytochelatin-inspired copolymers containing carboxylate and thiolate moieties. Titration calorimetry results indicate that the coexistence of both moieties is essential for the excellent Cd2+ ion-capturing capacity of the copolymers. The obtained dissociation constant, KD ~ 1 nM for Cd2+ ion, is four-to-five orders of magnitude higher than that for peptides mimicking the sequence of endogenous phytochelatin. Furthermore, infrared and nuclear magnetic resonance spectroscopy results unravel the mechanism underlying complex formation at the molecular level. The grafting of 0.1 g bio-inspired copolymers onto silica microparticles and cellulose membranes helps concentrate the copolymer-coated microparticles in ≈3 mL volume to remove Cd2+ ions from 0.3 L of water within 1 h to the drinking water level (<0.03 µM). The obtained results suggest that hyperconfinement of bio-inspired polymers in flow-through systems can be applied for the highly selective removal of harmful contaminants from the environmental water.


Asunto(s)
Metales Pesados , Polímeros , Purificación del Agua , Polímeros/química , Purificación del Agua/métodos , Metales Pesados/química , Metales Pesados/aislamiento & purificación , Biodegradación Ambiental , Contaminantes Químicos del Agua/química , Cadmio/química , Fitoquelatinas/metabolismo , Fitoquelatinas/química , Celulosa/química , Dióxido de Silicio/química , Iones/química
16.
PLoS One ; 19(7): e0304809, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38995923

RESUMEN

Supporting cells(SCs) have been demonstrated to be a reliable source for regenerating hair cells(HCs). Previous research has reported that Lgr5+ SCs can regenerate HCs both in vitro and in vivo. However, there is limited knowledge about the impact of the material on Lgr5+ cells. In this study, Lgr5+ cells were isolated from neonatal Lgr5-EGFP-CreERT2 transgenic mice by flow cytometry and then plated on self-assembled silica beads (SB). Lgr5+ cell differentiation was observed by immunofluorescence. We found that in the direct differentiation assay, the SB group generated more hair cells than the control group(*p < 0.05). Especially in the SB group, Lgr5+ progenitors generated significantly more Myo7a+ HCs outside of the colony than in the control group(**p < 0.01). In the sphere differentiation assay, we found that the diameter of spheres in the SB group was significantly larger compared to those of the control group(**p < 0.01). However, the difference in the ratio of myo7a+ cell counts was not obvious(P>0.05). The experiment proved that the self-assembled silica beads could promote the differentiation of Lgr5+ progenitors in vitro. Our findings implicate that nanostructures of self-assembled silica beads can be used as vectors for stem cell research in the inner ear.


Asunto(s)
Diferenciación Celular , Ratones Transgénicos , Nanoestructuras , Receptores Acoplados a Proteínas G , Dióxido de Silicio , Células Madre , Animales , Dióxido de Silicio/química , Receptores Acoplados a Proteínas G/metabolismo , Células Madre/citología , Células Madre/metabolismo , Ratones , Nanoestructuras/química , Células Cultivadas
17.
Molecules ; 29(13)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38999074

RESUMEN

This study presents properties of hydroethanolic extracts prepared from Pinot Noir (PN) grape pomace through conventional, ultrasound-assisted or solvothermal extraction. The components of the extracts were identified by HPLC. The total content of polyphenols, flavonoids, anthocyanins, and condensed tannins, as well as antioxidant activity and α-glucosidase inhibitory activity of extracts were evaluated using UV-vis spectroscopy. All extracts were rich in phenolic compounds, proving a good radical scavenging activity. The extract obtained by conventional extraction at 80 °C showed the best α-glucosidase inhibitory activity close to that of (-)-epigallocatechin gallate. To improve the chemical stability of polyphenols, the chosen extract was incorporated in porous silica-based supports: amine functionalized silica (MCM-NH2), fucoidan-coated amine functionalized silica (MCM-NH2-Fuc), MCM-41, and diatomite. The PN extract exhibited moderate activity against Gram-positive S. aureus (MIC = 156.25 µg/mL) better than against Gram-negative E. coli (MIC = 312.5 µg/mL). The biocompatibility of PN extract, free and incorporated in MCM-NH2 and MCM-NH2-Fuc, was assessed on RAW 264.7 mouse macrophage cells, and the samples showcased a good cytocompatibility at 10 µg/mL concentration. At this concentration, PN and PN@MCM-NH2-Fuc reduced the inflammation by inhibiting NO production. The anti-inflammatory potential against COX and LOX enzymes of selected samples was evaluated and compared with that of Indomethacin and Zileuton, respectively. The best anti-inflammatory activity was observed when PN extract was loaded on MCM-NH2-Fuc support.


Asunto(s)
Antiinflamatorios , Antioxidantes , Hipoglucemiantes , Extractos Vegetales , Dióxido de Silicio , Vitis , Vitis/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/farmacología , Antioxidantes/química , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Animales , Ratones , Dióxido de Silicio/química , Células RAW 264.7 , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química , Porosidad , Polifenoles/farmacología , Polifenoles/química
18.
AAPS PharmSciTech ; 25(6): 165, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009915

RESUMEN

CaCO3 nanoparticles (nano-CaCO3) as nano-templates were prepared using CaCl2 and Na2CO3 solutions under controlled sonication (19.5 kHz). Using the same ultrasonic device, subsequently, hollow mesoporous silica nanoparticles (HMSNs) were obtained by the hard template of nano-CaCO3. HMSNs were selected as carriers for the antifungal drug voriconazole (VOR) loading to overcome poor water solubility. Three-dimensional CaCO3 nanosheets HMSNs were obtained under gentle sonication. Three-dimensional CaCO3 nanosheets of 24.5 nm (hydrodynamic diameter) were obtained under 17.6 W for 3 min. HMSNs were synthesized by double-template method with nano-CaCO3 as the hard template. Transmission electron microscopy measurements showed that the prepared HMSNs possess hollow structures with particle size between 110 and 120 nm. Nitrogen physisorption at -196 °C revealed that the HMSNs had high surface area (401.57 m2/g), high pore volume (0.11 cm3/g), and uniform pore size (2.22 nm) that facilitated the effective encapsulation of VOR in the HMSNs. The loading capacity of VOR (wt%) on the HMSNs was 7.96%, and the total VOR release amount of VOR-HMSNs material was 71.40% at 480 min. The kinetic model confirmed that the release mechanism of HMSNs nanoparticles followed Fickian diffusion at pH = 7.4 and 37 °C. Moreover, the cumulative VOR release at 42 °C (86.05%) was higher than that at 37 °C (71.40%). The cumulative release amount of VOR from the VOR-HMSNs material was 92.37% at pH = 5.8 at the same temperature. Both nano-CaCO3 templates and HMSNs were prepared by sonication at 19.5 kHz. The as-prepared HMSNs can effectively encapsulate VOR and released drug by Fickian diffusion.


Asunto(s)
Antifúngicos , Carbonato de Calcio , Nanopartículas , Tamaño de la Partícula , Dióxido de Silicio , Voriconazol , Nanopartículas/química , Carbonato de Calcio/química , Dióxido de Silicio/química , Voriconazol/química , Voriconazol/administración & dosificación , Porosidad , Antifúngicos/administración & dosificación , Antifúngicos/química , Portadores de Fármacos/química , Solubilidad , Liberación de Fármacos , Sonicación/métodos
19.
Mikrochim Acta ; 191(8): 477, 2024 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039391

RESUMEN

A novel biofuel cell (BFC)-based self-powered electrochemical immunosensing platform was developed by integrating the target-induced biofuel release and biogate immunoassay for ultrasensitive 17ß-estradiol (E2) detection. The carbon nanocages/gold nanoparticle composite was employed in the BFCs device as the electrode material, through which bilirubin oxidase and glucose oxidase were wired to form the biocathode and bioanode, respectively. Positively charged mesoporous silica nanoparticles (PMSN) were encapsulated with glucose molecules as biofuel and subsequently coated by the negatively charged AuNPs-labelled anti-E2 antibody (AuNPs-Ab) serving as a biogate. The biogate could be opened efficiently and the trapped glucose released once the target E2 was recognized and captured by AuNPs-Ab due to the decreased adhesion between the antigen-antibody complex and PMSN. Then, glucose oxidase oxidized the glucose to produce a large number of electrons, resulting in significantly increased open-circuit voltage (EOCV). Promisingly, the proposed BFC-based self-powered immunosensor demonstrated exceptional sensitivity for the detection of E2 in the concentration range from 1.0 pg mL-1 to 10.0 ng mL -1, with a detection limit of 0.32 pg mL-1 (S/N = 3). Furthermore, the prepared BFC-based self-powered homogeneous immunosensor showed significant potential for implementation as a viable prototype for a mobile and an on-site bioassay system in food and environmental safety applications.


Asunto(s)
Fuentes de Energía Bioeléctrica , Técnicas Biosensibles , Estradiol , Glucosa Oxidasa , Oro , Límite de Detección , Nanopartículas del Metal , Inmunoensayo/métodos , Estradiol/química , Estradiol/análisis , Oro/química , Glucosa Oxidasa/química , Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Humanos , Electrodos , Glucosa/análisis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/química , Anticuerpos Inmovilizados/inmunología , Dióxido de Silicio/química , Enzimas Inmovilizadas/química
20.
Sci Adv ; 10(28): eadl4913, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38985878

RESUMEN

The pathophysiology of silicosis is poorly understood, limiting development of therapies for those who have been exposed to the respirable particle. We explored mechanisms of silica-induced pulmonary fibrosis in human lung samples collected from patients with occupational exposure to silica and in a longitudinal mouse model of silicosis using multiple modalities including whole-lung single-cell RNA sequencing and histological, biochemical, and physiologic assessments. In addition to pulmonary inflammation and fibrosis, intratracheal silica challenge induced osteoclast-like differentiation of alveolar macrophages and recruited monocytes, driven by induction of the osteoclastogenic cytokine, receptor activator of nuclear factor κΒ ligand (RANKL) in pulmonary lymphocytes, and alveolar type II cells. Anti-RANKL monoclonal antibody treatment suppressed silica-induced osteoclast-like differentiation in the lung and attenuated pulmonary fibrosis. We conclude that silica induces differentiation of pulmonary osteoclast-like cells leading to progressive lung injury, likely due to sustained elaboration of bone-resorbing proteases and hydrochloric acid. Interrupting osteoclast-like differentiation may therefore constitute a promising avenue for moderating lung damage in silicosis.


Asunto(s)
Diferenciación Celular , Osteoclastos , Fibrosis Pulmonar , Dióxido de Silicio , Silicosis , Dióxido de Silicio/toxicidad , Animales , Humanos , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/patología , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/metabolismo , Ratones , Silicosis/patología , Silicosis/metabolismo , Silicosis/etiología , Diferenciación Celular/efectos de los fármacos , Ligando RANK/metabolismo , Modelos Animales de Enfermedad , Masculino , Pulmón/patología , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patología , Macrófagos Alveolares/efectos de los fármacos , Femenino
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