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1.
Sci Rep ; 14(1): 5346, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438431

RESUMO

Diabetic wound healing is sluggish, often ending in amputations. This study tested a novel, two-punch therapy in mice-Selenium nanoparticles (Se NPs) and platelet-rich plasma (PRP)-to boost healing. First, a mouse model of diabetes was created. Then, Se NPs were crafted for their impressive antioxidant and antimicrobial powers. PRP, packed with growth factors, was extracted from the mice's blood. Wound healing was tracked for 28 days through photos, scoring tools, and tissue analysis. Se NPs alone spurred healing, and PRP added extra fuel. Furthermore, when used in combination with PRP, the healing process was accelerated due to the higher concentration of growth factors in PRP. Notably, the combination of Se NPs and PRP exhibited a synergistic effect, significantly enhancing wound healing in diabetic mice. These findings hold promise for the treatment of diabetic wounds and have the potential to reduce the need for lower limb amputations associated with diabetic foot ulcers. The innovative combination therapy using Se NPs and PRP shows great potential in expediting the healing process and addressing the challenges of impaired wound healing in individuals with diabetes. This exciting finding suggests this therapy could change diabetic wound management, potentially saving limbs and improving lives.


Assuntos
Diabetes Mellitus Experimental , Nanopartículas , Plasma Rico em Plaquetas , Selênio , Animais , Camundongos , Selênio/farmacologia , Cicatrização
2.
Sci Rep ; 14(1): 4184, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378707

RESUMO

In this study, polymeric graphitic carbon nitride (g-C3N4) semiconductors was synthesized via a thermal condensation method. Subsequently, Ag/AgBr nanoparticles with varying ratios were decorated onto the g-C3N4 surface using the water/oil emulsion method. The resulting nanocomposites were characterized using XRD for phase identification and structural analysis, HR-TEM and SEM&EDAX for morphological structure, particle size, and elemental composition analysis, and XPS for investigating the chemical state and electronic structure. The impact of Ag/AgBr content on the optical properties of g-C3N4 were also studied such as (optical bandgap (Eg), refractive index (n), extinction coefficient (k), optical conductivity (σopt) and dielectric function (ε*)), Electrochemical impedance spectroscopy (EIS), PL spectroscopy and Chrono-amperometric investigations were conducted to assess the charge transfer capabilities and long-term durability of the prepared nanocomposites. The results revealed a reduction in Ag/AgBr particle size with an increase in g-C3N4 content, accompanied by a decrease in the optical bandgap from 2.444 eV to 2.393 eV. Furthermore, the nanocomposites exhibited enhanced degradation efficiencies of RhB dye, with the highest tested content of Ag/AgBr achieving 100% degradation after 120 min of irradiation. However, the challenge of catalyst separation after the degradation process remained. To address this issue, we developed a novel approach by impregnating Ag/AgBr@g-C3N4 photocatalyst onto a floating porous sponge using a simple sugar-template technique, offering potential as a reusable photocatalyst material. Furthermore, the 3D PDMS - Ag/AgBr@g-C3N4 photocatalyst was evaluated and found to maintain nearly the same photocatalytic efficiency for up to 5 consecutive cycles.

3.
Sci Rep ; 14(1): 621, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182636

RESUMO

Particulate matters (PMs) pose significant risks to human health and the environment, necessitating research to enhance air purification filters and reduce harmful emissions. This study focuses on the preparation of carbon nanomaterials, including graphitic carbon nitride nanosheets (g-C3N4 NSs), reduced graphene oxide (r-GO), and carbon nanotubes (CNT), for modifying filters in air particle monitoring devices. The objective is to investigate the impact of these nanomaterials on enhancing PM adsorption efficiency. Quantitative and qualitative analyses of the modified filters' adsorption efficiency towards PMs are performed using spectroscopic techniques such as Energy-Dispersive X-ray Spectroscopy (EDX), Inductively Coupled Plasma (ICP), and Laser-Induced Breakdown Spectroscopy (LIBS). The results reveal that CNT-modified filters exhibit superior adsorption efficiency compared to the control, g-C3N4, and r-GO-modified filters. The exceptional performance of CNTs is attributed to their large specific surface area and pore volume. Additionally, LIBS demonstrates its capability to detect heavy metals like Cd, which remain undetected by EDX and ICP. The technique proves sensitive for heavy metal monitoring. This novel approach is expected to garner significant attention and contribute to the development of improved air purification technologies.

5.
Sci Rep ; 13(1): 19730, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957193

RESUMO

Microalgae have the potential to become the primary source of biodiesel, catering to a wide range of essential applications such as transportation. This would allow for a significant reduction in dependence on conventional petroleum diesel. This study investigates the effect of biostimulation techniques utilizing nanoparticles of Magnesium oxide MgO, Calcium hydroxyapatite Ca10(PO4)6(OH)2, and Zinc oxide ZnO to enhance the biodiesel production of Chlorella sorokiniana. By enhancing cell activity, these nanoparticles have demonstrated the ability to improve oil production and subsequently increase biodiesel production. Experimentally, each nanomaterial was introduced at a concentration of 15 mg L-1. The results have shown that MgO nanoparticles yielded the highest biodiesel production, with a recorded yield of 61.5 mg L-1. Hydroxyapatite nanoparticles, on the other hand, facilitated lipid accumulation. ZnO nanoparticles showcased a multifaceted advantage by enhancing both growth and lipid content. Thus, it is suggested that these nanoparticles can be used effectively to increase the lipid content of microalgae. These findings highlight the potential of biostimulation strategies utilizing MgO, hydroxyapatite, and zinc oxide nanoparticles to bolster biodiesel production.


Assuntos
Chlorella , Microalgas , Nanopartículas , Óxido de Zinco , Biocombustíveis , Óxido de Magnésio , Biomassa , Lipídeos , Hidroxiapatitas
6.
Food Chem Toxicol ; 179: 113979, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37544473

RESUMO

Cisplatin (Cis) is a treatment for testicular germ-cell tumors (TGCTs). Unfortunately, it causes testicular toxicity due to releasing reactive oxygen species (ROS) causing damage to testicular cells and chromosomes. The current study aimed to investigate the ameliorative effect of selenium nanoparticles (SeNPs) against cisplatin testicular toxicity in male rats by assessment of body weight, testis weight, oxidative stress markers in testis homogenates as (malondialdehyde (MDA), Superoxide dismutase (SOD), Glutathione reduced (GSH), Glutathione peroxidase (GSH âˆ¼ PX) and Catalase (CAT)), gene expression, testosterone concentration (T), sperm characteristics (count, motility and abnormality) and testicular histopathology. Methods: Thirty adult male rats divided equally into four groups; a single dose intraperitoneally injection of cisplatin (10 mg/kg) and selenium nanoparticles (2 mg/kg/day) were administrated alone or in combination. Cis group showed a decrease in body weight, testis weight, antioxidant activities (SOD, GSH, GSH âˆ¼ PX and CAT), T concentration and steroidogenetic expression, the data recorded an increase in MDA levels and sperm abnormality, meanwhile histopathology of testis sections showed degenerative changes in the seminiferous tubules. The co-administration of selenium nanoparticles ameliorated the harmful effects of cisplatin. In conclusion; SeNPs through its antioxidant potential may be useful to prevent the testicular toxicity induced by cisplatin to the rat testis by reducing oxidative stress.


Assuntos
Nanopartículas , Selênio , Ratos , Masculino , Animais , Testículo , Cisplatino/farmacologia , Antioxidantes/farmacologia , Selênio/farmacologia , Ratos Wistar , Sêmen/metabolismo , Estresse Oxidativo , Glutationa/metabolismo , Superóxido Dismutase/metabolismo , Peso Corporal
7.
Sci Rep ; 13(1): 2720, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792676

RESUMO

Environmental issues are brought up concerning the production of Portland cement. As a result, biocement serves as a reliable substitute for Portland cement in green construction projects. This study created a brand-new technique to create high-quality biocement from agricultural wastes. The technique is based on nanomaterials that improve and accelerate the "Microbially Induced Calcite Precipitation (MICP)" process, which improves the quality of the biocement produced. The mixture was further mixed with the addition of 5 mg/l of graphitic carbon nitride nanosheets (g-C3N4 NSs), alumina nanoparticles (Al2O3 NPs), or silica nanoparticles (SiO2 NPs). The cement: sand ratio was 1:3, the ash: cement ratio was 1:9, and water: cement ratio was 1:2. Cubes molds were prepared, and then cast and compacted. Subsequent de-molding, all specimens were cured in nutrient broth-urea (NBU) media until testing at 28 days. The medium was replenished at an interval of 7 days. The results show that the addition of 5 mg/l of g-C3N4 NSs with corncob ash delivered the highest "Compressive Strength" and the highest "Flexural Strength" of biocement mortar cubes of 18 and 7.6 megapascal (MPa), respectively; and an acceptable "Water Absorption" (5.42%) compared to all other treatments. This treatment delivered a "Compressive Strength", "Flexural Strength", and "Water Absorption" reduction of 1.67, 1.26, and 1.21 times the control (standard Portland cement). It was concluded that adding 5 mg/l of g-C3N4 NSs to the cementitious mixture enhances its properties, where the resulting biocement is a promising substitute for conventional Portland cement. Adding nanomaterials to cement reduces its permeability to ions, increasing its strength and durability. The use of these nanomaterials can enhance the performance of concrete infrastructures. The use of nanoparticles is an effective solution to reduce the environmental impact associated with concrete production.

8.
Environ Sci Pollut Res Int ; 30(17): 51344-51355, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36809621

RESUMO

The design of reactors based on high performance photocatalysts is an important research in catalytic hydrogenation. In this work, modification of titanium dioxide nanoparticles (TiO2 NPs) was achieved by preparation of Pt/TiO2 nanocomposites (NCs) through photo-deposition method. Both nanocatalysts were used for the photocatalytic removal of SOx from the flue gas at room temperature in the presence of hydrogen peroxide, water, and nitroacetanilide derivatives under visible light irradiation. In this approach, chemical deSOx was achieved along with protection of the nanocatalyst from sulfur poising through the interaction of the released SOx from SOx-Pt/TiO2 surface with p-nitroacetanilide derivatives to produce simultaneous aromatic sulfonic acids. Pt/TiO2 NCs have a bandgap of 2.64 eV in visible light range, which is lower than the bandgap of TiO2 NPs, whereas TiO2 NPs have a mean size of 4 nm and a high specific surface area of 226 m2/g. Pt/TiO2 NCs showed high photocatalytic sulfonation of some phenolic compounds using SO2 as a sulfonating agent along with the existence of p-nitroactanilide derivatives. The conversion of p-nitroacetanilide followed the combination processes of adsorption and catalytic oxidation-reduction reactions. Construction of an online continuous flow reactor-high-resolution time-of-flight mass spectrometry system had been investigated, realizing real-time and automatic monitoring of completion the reaction. 4-nitroacetanilide derivatives (1a-1e) was converted to its corresponding sulfamic acid derivatives (2a-2e) in 93-99% isolated yields of within 60 s. It is expected to offer a great opportunity for ultrafast detection of pharmacophores.


Assuntos
Nitrogênio , Titânio , Nitrogênio/química , Titânio/química , Ácidos Sulfônicos , Catálise
9.
Environ Sci Pollut Res Int ; 29(23): 34887-34897, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35040058

RESUMO

Agricultural and agro-industrial wastes (e.g., potato peel waste) are causing severe environmental problems. The processes of pretreatment, saccharification, and fermentation are the major obstacles in bioethanol production from wastes and must be overcome by efficient novel techniques. The effect of exposing the fungi (yeast) Saccharomyces cerevisiae to laser source with the addition of graphitic carbon nitride nanosheets (g-C3N4) with different concentrations on bioethanol production was investigated through the implementation of a batch anaerobic system and using potato peel waste (PPW). Dichromate test was implemented as quantitative analysis for quantification of the bioethanol yield. The benefits of this test were the appearance of green color indicating the identification of ethanol (C2H5OH) by bare eye and the ease to calculate the bioethanol yield through UV-visible spectrophotometry. The control sample (0.0 ppm of g-C3N4) showed only a 4% yield of bioethanol; however, by adding 150 ppm to PPW medium, 22.61% of ethanol was produced. Besides, laser irradiations (blue and red) as influencing parameters were studied with and without the addition of g-C3N4 nanomaterials aiming to increase the bioethanol. It was determined that the laser irradiation can trigger the bioethanol production (in case of red: 13.13% and in case of blue: 16.14% yields, respectively) compared to the control sample (in absence of g-C3N4). However, by adding different concentrations of g-C3N4 nanomaterials from 5 to 150 ppm, the bioethanol yield was increased as follows: in case of red: 56.11% and, in case of blue: 56.77%, respectively. It was found that using fungi and exposing it to the blue laser diode source having a wavelength of 450 nm and a power of 250 mW for a duration of 30 min with the addition of 150 mg L-1 of g-C3N4 nanomaterials delivered the highest bioethanol yield from PPW.


Assuntos
Nanoestruturas , Solanum tuberosum , Biocombustíveis , Etanol , Fermentação , Grafite , Compostos de Nitrogênio , Saccharomyces cerevisiae , Solanum tuberosum/microbiologia
10.
Environ Sci Pollut Res Int ; 29(2): 2588-2597, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34374017

RESUMO

In order to improve the economic feasibility and environmental sustainability of microalgal bioethanol production, a nontoxic, copious agricultural waste, sugarcane bagasse aqueous extract (SBAE) was used for cultivating Nannochloropsis oculata microalga (NNO-1 UTEX Culture LB 2164) as potential sources of substitutes for traditional nutrition to reduce the costs in cultivation through acid digestion and enzymatic treatment before being fermented by Saccharomyces cerevisiae (NRRLY-2034). The primary target of this research was to find out the ethanol from hydrolysate of the defatted biomass of N. oculata grown mixotrophically on SBAE and CO2 as carbon sources. For acid hydrolysis (AH), the highest carbohydrate yield 252.84 mg/g DW has been obtained with 5.0% (v/v) H2SO4 at 121 °C for 15 min for defatted biomass cultivated mixotrophically on sugarcane bagasse aqueous extract (SBAE) regarding 207.41 mg/g DW for defatted biomass cultivated autotrophically (control treatment). Whereas, the highest levels of reducing sugars has been obtained with 4.0% (v/v) H2SO4 157.47±1.60 mg/g DW for defatted biomass cultivated mixotrophically compared with 135.30 mg/g DW for the defatted control treatment. The combination of acid hydrolysis 2.0% (v/v) H2SO4 followed by enzymatic treatment (AEH) increased the carbohydrate yields to 268.53 mg/g DW for defatted biomass cultivated mixotrophically on SBAE regarding 177.73 mg/g DW for the defatted control treatment. However, the highest levels of reducing sugars have been obtained with 3.0% (v/v) H2SO4 followed by enzyme treatment that gave 232.39±1.77 for defatted biomass cultivated mixotrophically on SBAE and 150.75 mg/g DW for the defatted control treatment. The sugar composition of the polysaccharides showed that glucose was the principal polysaccharide sugar (60.7-62.49%) of N. oculata defatted biomass. Fermentation of the hydrolysates by Saccharomyces cerevisiae for the acid pretreated defatted biomass samples gave ethanol yield of 0.86 g/L (0.062 g/g sugar consumed) for control and 1.17 g/L (0.069 g/g sugar consumed) for SBAE mixotrophic. Whereas, the maximum ethanol yield of 6.17±0.47 g/L (0.26±0.11 g/g sugar consumed) has been obtained with samples from defatted biomass grown mixotrophically (SBAE mixotrophic) pretreated with acid coupled enzyme hydrolysis.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Etanol , Fermentação , Hidrólise
11.
Aquat Toxicol ; 242: 106054, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34923218

RESUMO

Contamination of aquatic systems with heavy metals (HM) is of great concern owing to their deleterious impact on living organism. The current research is focused on application of silica particles with new functionalized properties (magnetic silica; SiMag or Nanoporous silica; SiNPs) and their efficacy to mitigate lead (pb) toxicity in Nile tilapia. One thousand fingerlings were distributed: two control groups (negative; without pb toxicity (NC) positive (with pb toxicity) and other four groups received two silica sources (SiMag or SiNPs) with two levels (400 and 600 mg/kg diet) for 56 days then exposed to pb for 30 days. Before toxicity exposure, maximum growth, and most improved feed conversion ratio and biochemical parameters were noticed with higher SiMag or SiNPs levels. Serum antioxidant enzymes and their transcriptional levels in muscle and liver were boosted in groups received SiMag or SiNPs. After toxicity exposure, hematological and antioxidants biomarkers maintained at adequate levels in SiMag or SiNPs. Prominent reduction of residual pb in gills, liver, kidney, and muscle was observed in SiNPs then SiMag groups. Interestingly, the maximum down-regulation of P450, caspase-3 and HSP-70 and MT were observed in groups received 600 mg/kg diet of SiMag or SiNPs. The higher level of P53 in liver and gills was detected in PC, inversely reduced in SiMag or SiNPs. Severity of the histopathological alterations in examined organs greatly reduced in groups received SiMag or SiNPs, unlike it were induced in PC group. In conclusion, higher SiMag or SiNPs levels not only mitigate negatives impact of pb toxicity in fish but also ensure its safety for human consumption.


Assuntos
Ciclídeos , Chumbo , Nanopartículas , Dióxido de Silício , Poluentes Químicos da Água , Animais , Antioxidantes/metabolismo , Apoptose , Bioacumulação , Ciclídeos/metabolismo , Chumbo/toxicidade , Poluentes Químicos da Água/toxicidade
12.
Luminescence ; 36(8): 1933-1944, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34323370

RESUMO

New photochromic film was developed toward the preparation of anti-counterfeiting documents utilizing inorganic/organic nanocomposite enclosing a photoluminescent inorganic pigment and a polyacrylic binder polymer. To generate a translucent film from pigment/polyacrylic nanocomposite, the phosphorescent strontium aluminum oxide pigment should be well-dispersed in the solution of the polyacrylic-based binder without agglomeration. The photochromic nanocomposite was applied efficiently onto commercial cellulose paper documents utilizing the effective and economical spray-coating technology followed with thermofixation. A homogeneous photochromic film was immobilized onto cellulose paper surface to introduce a transparent film changing to greenish-yellow upon exposure to ultraviolet light as depicted by CIE coloration measurements. The photochromic effect was monitored at lowest pigment concentration (0.25 wt%). The spray-coated paper documents exhibit two absorbance bands at 256 and 358 nm, and two fluorescence peaks at 433 and 511 nm. The morphologies of the spray-coated documents were explored. The spray-coated paper sheets showed a reversible photochromic effect without fatigue under ultraviolet irradiation. The rheology of the produced photochromic composites as well as the mechanical properties and photostability of the spray-coated documents were studied.


Assuntos
Metais Terras Raras , Nanocompostos , Óxido de Alumínio , Celulose , Estrôncio
13.
Environ Sci Pollut Res Int ; 28(35): 48517-48534, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33907960

RESUMO

This research was intended to evaluate the antidiabetic effect of single or combined administration of nanoparticles of zinc oxide nanoparticles (ZnONPs), chromium oxide nanoparticles (Cr2O3NPs), and selenium nanoparticles (SeNPs), on genetic and metabolic insult in fructose/streptozotocin diabetic rat model. Type 2 diabetes mellitus was induced by feeding sixty adult male albino rats with a high fructose diet accompanied by a single i.p. injection of streptozotocin (STZ). The rats were divided into 6 groups (10 rats/each) and the doses of nanoparticles were 10 mg/kg b.wt for ZnONPs, 1 mg/kg b.wt for Cr2O3, and 0.4 mg/kg b.wt for SeNPs. The results displayed that diabetes significantly decreased bodyweight, serum insulin, C-peptide, adiponectin levels, erythrocyte glutathione peroxidase, serum superoxide dismutase activities, high-density lipoprotein cholesterol (HDL-C), and total antioxidant capacity while causing a substantial increase in serum glucose, C-reactive protein, atherogenic index, HOMA-IR, malondialdehyde, lipid profile, interleukin-6 levels, and liver function and kidney function parameters. Furthermore, the findings showed a decrease in insulin receptor substrate-1 (IRS-1) hepatic mRNA expression level and peroxisome proliferator-activated receptor (PPAR-γ) adipocyte mRNA expression level in type 2 diabetic rats. DNA damage was confirmed by performing the comet assay. Moreover, histological observation of pancreatic and hepatic tissues was performed, which were consistent with the biochemical results. The present study confirmed that oral administration of ZnONPs, Cr2O3NPs, SeNPs, and their mixture improved all the biochemical and genetic parameters toward normal levels and ameliorated the diabetic consequences that were manifested by restricting cellular DNA damage which maintaining pancreatic and hepatic tissues from oxidative damage. The best reported antidiabetic effect was observed in the mixture administered group.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Nanopartículas , Selênio , Óxido de Zinco , Animais , Antioxidantes/metabolismo , Glicemia/metabolismo , Compostos de Cromo , Dano ao DNA , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Frutose/metabolismo , Fígado/metabolismo , Masculino , Estresse Oxidativo , Ratos , Selênio/metabolismo , Estreptozocina/metabolismo , Óxido de Zinco/metabolismo
14.
Saudi J Biol Sci ; 28(1): 484-491, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424331

RESUMO

Hyaluronic acid (HA) has great importance in biomedical applications. In this work, a novel nanoparticle-based method that stimulates the hyaluronic acid (HA) production by the bacteria Streptococcus equi subsp. Zooepidemicus has been reported. CNTs with diameters of 40-50 nm and lengths of about 20 mm were used at four different concentrations (0, 10, 25, 50, and 100 µg) to the bacteria and determined the mass of the produced HA in dependence on the exposure time under UV-irradiation. The results clearly showed that the exposure for one minute with low power UV light (254 nm) and 100 µg (CNTs) treatments steadily increased HA production from the control (0.062 g/L) to the highest value (0.992) g/L of HA. The incubation of the streptococci with CNTs led to an increase of the HA production by a factor of 4.23 after 300S exposure time under UV light, whereas the HA production was no significant enhancement under visible light. It is explained that the CNTs nanoparticle-stimulated increase of the HA production with the internalization of the nanoparticles by the bacteria since they "serve as co-enzymes" under induced mutation by UV-irradiation. Transformation process was carried out and showed that the major protein band of Streptococcus equi was observed in the Streptococcus DH5α. RAPD analysis indicates that the amplified DNA fragments and the percentage of polymorphism was similar between Streptococcus equi and Streptococcus DH50α. The chemical structure and molecular weight of the photoproduced HA from Streptococcus equi was similar to the chemical structure of the standard sample.

15.
Saudi J Biol Sci ; 28(1): 78-89, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32868971

RESUMO

Viral infections pose significant health challenges globally by affecting millions of people worldwide and consequently resulting in a negative impact on both socioeconomic development and health. Corona virus disease 2019 (COVID-19) is a clear example of how a virus can have a global impact in the society and has demonstrated the limitations of detection and diagnostic capabilities globally. Another virus which has posed serious threats to world health is the human immunodeficiency virus (HIV) which is a lentivirus of the retroviridae family responsible for causing acquired immunodeficiency syndrome (AIDS). Even though there has been a significant progress in the HIV biosensing over the past years, there is still a great need for the development of point of care (POC) biosensors that are affordable, robust, portable, easy to use and sensitive enough to provide accurate results to enable clinical decision making. The aim of this study was to present a proof of concept for detecting HIV-1 pseudoviruses by using anti-HIV1 gp41 antibodies as capturing antibodies. In our study, glass substrates were treated with a uniform layer of silane in order to immobilize HIV gp41 antibodies on their surfaces. Thereafter, the HIV pseudovirus was added to the treated substrates followed by addition of anti-HIV gp41 antibodies conjugated to selenium nanoparticle (SeNPs) and gold nanoclusters (AuNCs). The conjugation of SeNPs and AuNCs to anti-HIV gp41 antibodies was characterized using UV-vis spectroscopy, transmission electron microscopy (TEM) and zeta potential while the surface morphology was characterized by fluorescence microscopy, atomic force microscopy (AFM) and Raman spectroscopy. The UV-vis and zeta potential results showed that there was successful conjugation of SeNPs and AuNCs to anti-HIV gp41 antibodies and fluorescence microscopy showed that antibodies immobilized on glass substrates were able to capture intact HIV pseudoviruses. Furthermore, AFM also confirmed the capturing HIV pseudoviruses and we were able to differentiate between substrates with and without the HIV pseudoviruses. Raman spectroscopy confirmed the presence of biomolecules related to HIV and therefore this system has potential in HIV biosensing applications.

16.
Curr Org Synth ; 18(1): 23-36, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33019933

RESUMO

The implementation of heterogeneous photo-nanocatalysts in organic syntheses has been investigated greatly in the last decade as a result of the increasing demand to achieve the organic reactions via the use of green approaches and through the availability of visible light source. Herein, the presented results describe the basic concepts and state-of-the-art of fundamental insight into key features that influence the catalytic performance in organic reactions to investigate and optimize a broad range of catalyzed organic transformations, that benefit the researchers in academia and chemical industry fields.


Assuntos
Luz , Catálise , Técnicas de Química Sintética
17.
Luminescence ; 36(4): 865-874, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33217143

RESUMO

Novel inorganic-organic hybrid photochromic and fluorescent ink for anticounterfeiting documents was developed using a pigment/resin ink formula enclosing a long-lived luminescent inorganic pigment with good thermal photostability. The produced ink exhibited an optimal excitation wavelength at 360 nm with an absorption colour and fluorescence changes in the printed document. To develop a transparent printed film from pigment/resin ink, the phosphorescent pigment has to be well dispersed physically without agglomeration. The pigment/resin hybrid was applied effectively onto commercial cellulose paper sheets using screen-printing technology. An homogeneous photochromic layer was deposited on cellulose paper document surface to afford a considerable greenish-yellow colour as demonstrated by CIE coloration measurements under a UV lamp, even at a pigment concentration as low as 0.1 wt% of the ink formulation. The printed paper sheets exhibited three excitation bands at 235, 274 and 378 nm and three emission bands at 416, 418 and 436 nm. Fluorescence optical microscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and wavelength-dispersive X-ray fluorescence spectrometry of the printed paper sheet were explored. The screen-printed paper sheets displayed a reversible and fast photochromism during ultraviolet irradiation without fatigue. The rheological properties, stability, and printability of the ink were studied.


Assuntos
Tinta , Estrôncio , Celulose , Corantes , Luminescência
18.
Naunyn Schmiedebergs Arch Pharmacol ; 393(8): 1405-1417, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32103295

RESUMO

Hesperidin (HD), a bioflavonoid, has been shown to exert hepatoprotective effects. Our aim is to investigate the possible protective effects of HD against methotrexate (MTX) hepatotoxicity in adult male Sprague-Dawley (SD) rats that were divided into four groups (10 rats/each) and were exposed to MTX with or without HD co-administration for consecutive 28 days. The results showed that HD significantly ameliorated MTX-induced increase in liver enzymes and histopathological changes. Hepatic oxidative stress was suppressed by HD, as evidenced by the decrease in malondialdehyde (MDA), with a concomitant increase in total antioxidant activity (TAC), catalase (CAT), and glutathione (GSH) levels. Moreover, co-administration of HD with MTX remarkably upregulated the expression of Nrf2 and HO-1 compared with the MTX group. By the decrease in nuclear factor-kB (NF-κB) pathway and tumor necrosis factor α (TNF-α), HD obviously attenuated inflammatory response in MTX-lesioned livers. Likewise, the downregulation of P53 by HD could explain its antiapoptotic effects as indicated by increase BCl2 and the significant decrease of caspase-9 mRNA expression as compared with the MTX group. Thus, these findings revealed the hepatoprotective nature of HD against MTX hepatotoxicity by attenuating the pro-inflammatory and apoptotic mediators and improving antioxidant aptitude.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Hesperidina/farmacologia , Fígado/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/metabolismo , Mediadores da Inflamação/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Metotrexato , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
19.
Environ Sci Pollut Res Int ; 26(28): 28749-28762, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31376127

RESUMO

Silver nanoparticles (AgNPs) have been widely produced for different industrial purposes. Recently, biogenic synthesis of AgNPs has emerged although the extent of effects from exposure, oral exposure in particular, to nanomaterials synthesized in such a manner remains elusive. The main objective of this study was to evaluate the effects of oral administration of a dose of 50 mg/Kg body weight AgNPs biosynthesized in baker's yeast (Saccharomyces cerevisiae) over a period of eight weeks on the reproductive performance and the possibility of a protective effect through co-administration of morin. Forty-eight male Sprague-Dawley rats were used in four experimental groups (control, morin-treated group, AgNP-treated, and AgNP + morin co-treatment). AgNPs produced no significant alteration in daily food intake or body weight. Both the absolute and relative testicular weights were significantly reduced but not the epididymal weight. Also, serum levels of urea, creatinine, uric acid, and liver enzymes were significantly elevated. Furthermore, AgNPs significantly downregulated the hypothalamic-pituitary-gonadal axis. This corresponds to lower motility and viability percent, reduced sperm concentration, and a higher abnormality ratio as well as a prominent alteration in the blood-testis barrier (BTB) and testicular histology and induction of testicular apoptosis and oxidative stress. The supplementation of morin evidently restored most of the reproductive characters to its physiological range. We can conclude that exposure to the biologically synthesized AgNPs for an extended period of time has proven to be a health risk that can be ameliorated via oral administration of some bioactive agents including morin.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacocinética , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Administração Oral , Animais , Apoptose , Barreira Hematotesticular , Epididimo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos
20.
Carbohydr Polym ; 192: 135-142, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29691005

RESUMO

This work aims at developing a novel hyaluronic acid (HA) production method using magnetic nanoparticles (NPs). In a separate process, HA was produced with the addition of the amino acids (AA) as bio-additives. Regarding the NPs additives, the results showed that the highest dry weight of the produced HA was 0.264 g/l with the addition of 20 mg/l of Fe3O4 NPs. Concerning the AA additives, the results showed that the highest dry weight of the produced HA was 0.079 g/l with the addition of 0.26 g/l of glutamic acid (GA) compared to the control produced 0.065 g/l. These results led to further develop a novel HA production method which is preparing the Fe3O4 NPs using GA as stabilizer, where the results showed that dry weight of the produced HA was 0.435 g/l with the addition of 20 mg/l of Fe3O4-GA NPs.

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