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1.
Mikrochim Acta ; 190(3): 90, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36786882

RESUMEN

A green, environmentally friendly protocol was developed for ultrasensitive and highly specific recognition of prostate-specific antigen (PSA) based on the ECL effect of luminol supported by chitosan-silver nanoparticles (CS/AgNPs) nanocomposites. The transducing surface was fabricated through two consecutive electrodeposition steps of gold nanoparticles (AuNPs) and chitosan (CS)-AgNPs-luminol electrochemiluminophore onto the glassy carbon electrode. In addition to an appropriate desirable biocompatibility, the electrochemical synthesis presents low-cost preparation and ultrafast determination opportunity. AgNPs play a linking role to attach luminol, as an ECL agent to the CS support via donor-acceptor bonds between Ag atoms with NH groups of luminol and CS. Also, AgNPs can amplify the ECL intensity as a consequence of their excellent specific surface area and conductivity. To enhance the performance of the nanobiosensor, AuNPs were also used due to their high-specific surface area and excellent affinity toward amine groups of CS. Based on this high-performance analysis strategy, ultrasensitive screening of PSA was attained with a desirable limit of detection of 0.6 ng mL-1 and a broad linear range between 1 pg mL-1 and 10 ng⋅mL-1 (R2=0.994). Approximately, the same results were recorded for the analysis of the unprocessed serum samples of patients with prostate cancer at different stages. This research provided significant insight into electrografting methods to construct ECL transducers for clinical monitoring of PSA and other tumor biomarkers in the clinical setting.


Asunto(s)
Quitosano , Nanopartículas del Metal , Nanocompuestos , Humanos , Masculino , Quitosano/química , Oro/química , Mediciones Luminiscentes/métodos , Luminol/química , Nanopartículas del Metal/química , Nanocompuestos/química , Antígeno Prostático Específico , Plata , Técnicas Electroquímicas
2.
Mikrochim Acta ; 190(10): 418, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37770707

RESUMEN

An electrochemical immunosensing platform was developed for the detection of receptor tyrosine kinase-orphan receptor-2 (ROR2) at a glassy carbon electrode (GCE) modified with the electrospun nanofiber containing polyvinylpyrrolidone (PVP), soy, and Au nanoparticles (AuNPs). The PVP/soy/AuNP nanofiber exhibited good electrochemical behavior due to synergistic effects between PVP, soy, and AuNPs. The PVP/soy in the modified film provided good mechanical strength, high porosity, flexible structures, and high specific surface area. On the other hand, the presence of AuNPs effectively improved conductivity, as well as the immobilization of anti-ROR2 on the modified GCE, leading to enhanced sensitivity. Various characterization approaches such as FE-SEM, FTIR, and EDS were used for investigating the morphological and structural features, and the elemental composition. The designed immunosensor performance was investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). Under optimum conditions with a working potential range from -0.2 to 0.6 V (vs. SCE), sensitivity, linear range (LR), limit of detection (LOD), and correlation coefficient (R2) were acquired at 122.26 µA/cm2 dec, 0.01-1000 pg/mL, 3.39 fg/mL, and 0.9974, respectively. Furthermore, the determination of ROR2 in human plasma samples using the designed immunosensing platform was examined and exhibited satisfactory results including good selectivity against other proteins, reproducibility, and cyclic stability.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Nanofibras , Humanos , Oro/química , Povidona , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Inmunoensayo , Carbono , Proteínas Tirosina Quinasas
3.
Molecules ; 27(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35056745

RESUMEN

Human Tau protein is the most reliable biomarker for the prediction of Alzheimer's disease (AD). However, the assay to detect low concentrations of tau protein in serum is a great challenge for the early diagnosis of AD. This paper reports an electrochemiluminescence (ECL) immunosensor for Tau protein in serum samples. Gold nanostars (AuNSs) decorated on carbon nitride nanosheets (AuNS@g-CN nanostructure) show highly strong and stable ECL activity compared to pristine CN nanosheets due to the electrocatalytic and surface plasmon effects of AuNSs. As a result of the strong electromagnetic field at branches, AuNSs showed a better ECL enhancement effect than their spherical counterpart. For the fabrication of a specific immunosensor, immobilized AuNSs were functionalized with a monoclonal antibody specific for Tau protein. In the presence of Tau protein, the ECL intensity of the immunosensor decreased considerably. Under the optimal conditions, this ECL based immunosensor exhibits a dynamic linear range from 0.1 to 100 ng mL-1 with a low limit of detection of 0.034 ng mL-1. The LOD is less than the Tau level in human serum; thus, this study provides a useful method for the determination of Tau. The fabricated ECL immunosensor was successfully applied to the detection of Tau, the biomarker in serum samples. Therefore, the present approach is very promising for application in diagnosing AD within the early stages of the disease.


Asunto(s)
Enfermedad de Alzheimer/sangre , Técnicas Biosensibles/métodos , Nanoestructuras/química , Proteínas tau/sangre , Área Bajo la Curva , Técnicas Biosensibles/instrumentación , Oro/química , Humanos , Límite de Detección , Mediciones Luminiscentes , Microscopía Electrónica de Rastreo , Nitrilos/química , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta , Proteínas tau/inmunología
4.
IUBMB Life ; 72(5): 825-841, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32026601

RESUMEN

Vasculogenic mimicry (VM) is regarded as a process where very aggressive cancer cells generate vascular-like patterns without the presence of endothelial cells. It is considered as the main mark of malignant cancer and has pivotal role in cancer metastasis and progression in various types of cancers. On the other hand, resistance to the antiangiogenesis therapies leads to the cancer recurrence. Therefore, development of novel chemotherapies and their combinations is urgently needed for abolition of VM structures and also for better tumor therapy. Hence, identifying compounds that target VM structures might be superior therapeutic factors for cancers treatment and controlling the recurrence and metastasis. In recent times, naturally occurring compounds, especially phytochemicals have obtained great attention due to their safe properties. Phytochemicals are also capable of targeting VM structure and also their main signaling pathways. Consequently, in this review article, we illustrated key signaling pathways in VM, and the phytochemicals that affect these structures including curcumin, genistein, lycorine, luteolin, columbamine, triptolide, Paris polyphylla, dehydroeffusol, jatrorrhizine hydrochloride, grape seed proanthocyanidins, resveratrol, isoxanthohumol, dehydrocurvularine, galiellalactone, oxacyclododecindione, brucine, honokiol, ginsenoside Rg3, and norcantharidin. The recognition of these phytochemicals and their safety profile may lead to new therapeutic agents' development for VM elimination in different types of tumors.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Fitoquímicos/uso terapéutico , Mimetismo Biológico/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Factor 2 de Crecimiento de Fibroblastos/antagonistas & inhibidores , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Flavonoides/uso terapéutico , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/irrigación sanguínea , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Neoplasias/irrigación sanguínea , Neoplasias/genética , Neoplasias/metabolismo , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Polifenoles/uso terapéutico , Proantocianidinas/uso terapéutico , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
5.
Mol Biol Rep ; 47(6): 4749-4765, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32424524

RESUMEN

Cancer is a major problem in the health system, and despite many efforts to effectively treat it, none has yet been fully successful. Angiogenesis and metastasis are considered as major challenges in the treatment of various cancers. Researchers have struggled to succeed with anti-angiogenesis drugs for the effective treatment of cancer, although new challenges have emerged in the treatment with the emergence of resistance to anti-angiogenesis and anti-metastatic drugs. Numerous studies have shown that different cancers can resist anti-angiogenesis drugs in a new process called vascular mimicry (VM). The studies have revealed that cells resistant to anti-angiogenesis cancer therapies are more capable of forming VMs in the in vivo and in vitro environment, although there is a link between the presence of VM and poor clinical outcomes. Given the importance of the VM in the challenges facing cancer treatment, researchers are trying to identify factors that prevent the formation of these structures. In this review article, it is attempted to provide a comprehensive overview of the molecules and main signaling pathways involved in VM phenomena, as well as the agents currently being identified as anti-VM and the role of VM in response to treatment and prognosis of cancer patients.


Asunto(s)
Neoplasias/irrigación sanguínea , Neoplasias/terapia , Neovascularización Patológica/metabolismo , Inhibidores de la Angiogénesis/metabolismo , Inhibidores de la Angiogénesis/farmacología , Antígenos CD , Cadherinas , Humanos , Neovascularización Patológica/fisiopatología , Pronóstico , Transducción de Señal
6.
Mikrochim Acta ; 186(12): 820, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31748898

RESUMEN

This review (with 118 refs.) discusses the progress made in electroanalytical methods based on the use of organic and inorganic nanomaterials for the determination of bacteria, specifically of E. coli, Salmonella, Staphylococcus, Mycobacterium, Listeria and Klebsiella species. We also discuss advantages and limitations of electrochemical methods. Strategies based on the use of aptamers, DNA and antibodies are covered. Following an introduction into electrochemical biosensing, a first large section covers methods for pathogen detection using metal nanoparticles, with subsections on silver nanoparticles, gold nanoparticles, magnetic nanoparticles and carbon-based nanomaterials. A second large section covers methods based on the use of organic nanocomposites, graphene and its derivatives. Other nanoparticles are treated in a final section. Several tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses challenges, and gives an outlook on potential future trends. Graphical abstract This review demonstrates the progress made in electroanalytical methods based on the use of organic and inorganic nanomaterials for the detection and determination of pathogenic bacteria. We also discuss advantages and limitations of electrochemical methods. Strategies based on the use of aptamers, DNA and antibodies are covered.


Asunto(s)
Bacterias/química , Nanoestructuras/química , Técnicas Biosensibles/métodos , Carbono/química , Técnicas Electroquímicas/métodos , Electrodos , Oro/química , Nanopartículas del Metal/química , Oxidación-Reducción , Plata/química , Propiedades de Superficie
7.
Mikrochim Acta ; 186(12): 838, 2019 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-31760523

RESUMEN

This review (with 77 refs.) describes the progress that has been made in biosensors for the detection of autoimmune diseases, mainly via detection of autoantibodies. In addition, specific proteins, cytokines and ions have also been introduced as promising diagnostic biomarkers. Following an introduction into the various kinds of autoimmune diseases, we first discuss the state of the art in respective electrochemical biosensors and nanobiosensors (with subsections on amperometric, impedimetric, voltammetric and photoelectrochemical methods). The next large chapter covers optical methods (with subsections on electrochemiluminescence, fluorescence and surface plasmon resonance). We then make a critical comparison between commercially available kits used for detection of autoimmune diseases with the established biosensors. Several Tables are also presented that give an overview on the wealth of methods and nanomaterials. Finally, in the conclusion part, we summarize the current status, addresse present issues, and give an outlook on potential future opportunities. Graphical abstractSchematic representation of various developed optical and electrochemical biosensors and nanobiosensors for rapid detection of autoimmune diseases nanobiosensors for rapid detection of autoimmune diseases which could significantly prevent irreversable tissue damages and increse the quality of life in these patients.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico , Técnicas Biosensibles , Técnicas Electroquímicas , Nanoestructuras/química , Nanotecnología , Humanos , Tamaño de la Partícula , Propiedades de Superficie
8.
Mikrochim Acta ; 185(9): 434, 2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30159750

RESUMEN

Caspase-3 plays a vital role in intrinsic and extrinsic pathways of programed cell death and in cell proliferation. Its detection is an important tool for early detection of some cancers and apoptosis-related diseases, and for monitoring the efficacy of pharmaceuticals and of chemo- and radiotherapy of cancers. This review (with 72 references) summarizes nanomaterial based methods for signal amplification in optical methods for the determination of caspase-3 activity. Following an introduction into the field, a first large section covers optical assays, with subsections on luminescent and chemiluminescence, fluorometric (including FRET based), and colorimetric assays. Further section summarize methods for bioimaging of caspase-3. A concluding section covers current challenges and future perspectives. Graphical Abstract ᅟ.


Asunto(s)
Apoptosis , Técnicas Biosensibles/métodos , Caspasa 3/metabolismo , Imagen Molecular/métodos , Nanoestructuras , Nanotecnología/métodos , Humanos
9.
Bioorg Chem ; 64: 74-84, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26722818

RESUMEN

Aldehyde oxidase (AO), a cytosolic molybdenum-containing hydroxylase, is predominantly active in liver and other tissues of mammalian species and involved in the metabolism of extensive range of aldehydes and nitrogen-containing compounds. A wide range of natural components including polyphenols are able to interfere with AO-catalyzed reactions. Polyphenols and flavonoids are one of the extensive secondary plant metabolites ubiquitously present in plants considered an important part of the human diet. The aim of the present study was to investigate inhibitory effect of selected phenolic compounds from three subclasses of aurone, flavanone and phenolic lactone compounds on the activity of AO, spectrophotometrically. AO enzyme was partially purified from liver of guinea pig. Then, inhibitory effects of 10 flavonoid compounds including 8 derivatives of 2-benzylidenebenzofuran-3(2H)-ones, as well as naringenin and ellagic acid on the activity of aldehyde oxidase were assessed compared with the specific inhibitor of AO, menadione. Among the phenolic compounds with inhibitory effects on the enzyme, ellagic acid (IC50=14.47 µM) was the most potent agent with higher inhibitory action than menadione (IC50=31.84 µM). The mechanisms by which flavonoid compounds inhibit AO activity have been also determined. The inhibitory process of the assessed compounds occurs via either a non-competitive or mixed mode. Although flavonoid compounds extensively present in the nature, mainly in dietary regimen, aurones with promising biological properties are not widely distributed in nature, so synthesis of aurone derivatives is of great importance. Additionally, aurones seem to provide a promising scaffold in medicinal chemistry for the skeleton of new developing drugs, so the results of the current study can be valuable in order to better understanding drug-food as well as drug-drug interaction and also appears to be worthwhile in drug development strategies.


Asunto(s)
Aldehído Oxidasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Animales , Benzofuranos/farmacología , Compuestos de Bencilideno/farmacología , Ácido Elágico/farmacología , Pruebas de Enzimas , Cobayas , Cinética , Ligandos , Hígado/enzimología , Masculino , Simulación del Acoplamiento Molecular
10.
Biologicals ; 44(6): 487-496, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27712979

RESUMEN

As a gene delivery method in breast cancer therapy, knocking down the undesired genes in the cancerous cells would be promising. Inhibitors of Apoptosis Protein (IAP) family genes are some of the genes whose responsibility is inhibition of apoptosis in cells. Silencing these genes seems to be helpful directing the tumor cells to death. siRNA sequence designed against survivin anti-apoptotic gene can play this role if carried to the cytoplasm. Here we prepared a positive charged biocompatible nano-sized particle made up of a Fe3O4 core covered respectively by polyacrylate (PA) and polyethyleneimine (PEI) layer, which could successfully deliver the siRNA into the MCF-7 cells. The particle structure was checked and having less than 50 nm diameter in size, positive charge and, safety towards MCF-7 cells besides being able to form nanoplexes with the siRNA strand helps it entering into the biologic assays part. The siRNA delivery evaluated via flowcytometry. Apoptosis induction was determined by DAPI staining. The efficiency of survivin gene knockdown was evaluated in mRNA and protein levels using Real time PCR and western blotting methods. Overall, the Fe3O4-PA-PEI nanoparticles can deliver siRNA effectively into the cytoplasm of the MCF-7 breast cancer cells and induce apoptosis.


Asunto(s)
Resinas Acrílicas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Nanopartículas de Magnetita/química , Mitoxantrona/farmacología , ARN Interferente Pequeño/farmacología , Resinas Acrílicas/química , Animales , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Células MCF-7 , Ratones , Mitoxantrona/química , ARN Interferente Pequeño/química , Survivin
11.
Pestic Biochem Physiol ; 124: 86-92, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26453235

RESUMEN

The vegetable leafminer (VLM), Liriomyza sativae (Diptera: Agromyzidae) is a serious pest of vegetable crops and ornamentals worldwide. In cropping systems with inappropriate management strategies, development of resistance to insecticides in leafminers is probable. Chlorpyrifos is a commonly used pesticide for controlling leafminers in Iran, but resistance to this insecticide in leafminers has not been characterized. In order to develop strategies to minimize resistance in the field and greenhouse, a laboratory selected chlorpyrifos resistant strain of L. sativae was used to characterize resistance and determine the rate of development and stability of resistance. Selecting for resistance in the laboratory after 23 generations yielded a chlorpyrifos resistant selected strain (CRSS) with a resistance ratio of 40.34, determined on the larval stage. CRSS exhibited no cross-resistance to other tested insecticides except for diazinon. Synergism and biochemical assays indicated that esterases (EST) had a key role in metabolic resistance to chlorpyrifos, but glutathione S-transferase (GST) and mixed function oxidase (MFO) were not mediators in this resistance. In CRSS acetylcholinesterase (AChE) was more active than the susceptible strain, Sharif (SH). AChE in CRSS was also less sensitive to inhibition by propoxur. The kinetics parameters (Km and Vmax) of AChE indicated that affinities and hydrolyzing efficiencies of this enzyme in CRSS were higher than SH. Susceptibility to chlorpyrifos in L. sativae was re-gained in the absence of insecticide pressure. Synergism, biochemical and cross-resistance assays revealed that overactivity of metabolic enzymes and reduction in target site sensitivity are probably joint factors in chlorpyrifos resistance. An effective insecticide resistance management program is necessary to prevent fast resistance development in crop systems.


Asunto(s)
Cloropirifos/toxicidad , Dípteros/efectos de los fármacos , Insecticidas/toxicidad , Acetilcolinesterasa/genética , Animales , Dípteros/enzimología , Dípteros/genética , Resistencia a los Insecticidas/genética
12.
Arch Pharm (Weinheim) ; 347(10): 738-47, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24956178

RESUMEN

Aldehyde oxidase (AO), an important enzyme in the biotransformation of drugs and xenobiotics, is inhibited by flavonoids. This enzyme can metabolize both aldehydes and N-heterocycles. In this work, a set of 15 flavonoids was assessed for inhibitory activity on the AO oxidation of vanillin as an aldehyde substrate. Spectrophotometrically determined IC50 values showed that myricetin, quercetin, and epicatechin were the most potent inhibitors. The results also revealed that the inhibition of vanillin oxidation by flavonoids was stronger than that of phenanthridine oxidation (an N-heterocyclic substrate) as reported previously. In order to investigate the important structural features responsible for the inhibitory effects of the studied flavonoids, a quantitative structure-activity relationship (QSAR) analysis was performed. This study showed that the size of the flavonoids was the most important factor inversely affecting their potencies. The QSAR model can be used more broadly to predict the AO inhibitory activity of flavonoid-like structures for application in food-drug and drug-drug interaction studies.


Asunto(s)
Aldehído Oxidasa/antagonistas & inhibidores , Diseño Asistido por Computadora , Diseño de Fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Flavonoides/química , Flavonoides/farmacología , Hígado/efectos de los fármacos , Simulación de Dinámica Molecular , Aldehído Oxidasa/química , Aldehído Oxidasa/metabolismo , Animales , Hígado/enzimología , Masculino , Estructura Molecular , Conformación Proteica , Relación Estructura-Actividad Cuantitativa , Ratas Sprague-Dawley
13.
J Econ Entomol ; 107(5): 1908-15, 2014 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-26309281

RESUMEN

The vegetable leafminer, Liriomyza sativae Blanchard, is a key pest of vegetable and ornamental crops worldwide and is mainly controlled by insecticides. The toxicity of fenpropathrin on adult flies of F1 generation of six Iranian populations of the pest was assessed using the residual glass vial method. The bioassay results showed significant differences in susceptibility to fenpropathrin among the populations tested. Resistance ratios ranged from 5.09 to 28.32. The resistant populations were reared in the greenhouse under fenpropathrin pressure for 14 mo and then susceptibility of both larvae and adults of these strains to fenpropathrin was evaluated. The resistance levels significantly increased in these populations. Further study demonstrated that diethyl maleate and triphenyl phosphate had no synergistic effects on fenpropathrin, however, this compound was significantly synergized by piperonyl butoxide in all tested populations. S,S,S-tributyl phosphorotrithioate also showed a slight synergism with fenpropathrin. Enzyme assays for general esterases, glutathione S-transferases and monooxygenases were performed on adults and larvae of L. sativae. The activity of glutathione s-transferase in different resistant and susceptible strains was not significantly different. The activity of esterases in resistant strains was higher than the susceptible strain. Monooxygenase levels also were higher in resistant strains compared with the susceptible strain. Synergism and biochemical assays revealed that esterases and monooxygenases have a major role in resistance of L. sativae to fenpropathrin.


Asunto(s)
Dípteros/efectos de los fármacos , Resistencia a los Insecticidas , Insecticidas/farmacología , Piretrinas/farmacología , Animales , Dípteros/crecimiento & desarrollo , Irán , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo
14.
Int J Biol Macromol ; 279(Pt 2): 134578, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39122064

RESUMEN

Because of the complex symptoms resulting from metabolic dysfunction in the wound microenvironment during bacterial infections, along with the necessity to combat free radicals, achieving prompt and thorough wound healing remains a significant medical challenge that has yet to be fully addressed. Moreover, the misuse of common antibiotics has contributed to the emergence of drug-resistant bacteria, underscoring the need for enhancements in the practical and commonly utilized approach to wound treatment. In this context, hydrogel dressings based on biological macromolecules with antibacterial and antioxidant properties present a promising new avenue for skin wound treatment due to their multifunctional characteristics. Despite the considerable potential of this innovative approach to wound care, comprehensive research on these multifunctional dressings is still insufficient. Consequently, the development of advanced biological macromolecule-based hydrogels, such as chitosan, alginate, cellulose, hyaluronic acid, and others, has been the primary focus of this study. These materials have been enriched with various antibacterial and antioxidant agents to confer multifunctional attributes for wound healing purposes. This review article aims to offer a comprehensive overview of the latest progress in this field, providing a critical theoretical basis for future advancements in the utilization of these advanced biological macromolecule-based hydrogels for wound healing.

15.
Biosens Bioelectron ; 257: 116319, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38669845

RESUMEN

This research presents a selective and sensitive electrochemical biosensor for the detection of the mesenchymal-epithelial transition factor (c-MET). The biosensing is based on a modification of the SPCE (screen-printed carbon electrode) with the electrospun nanofiber containing eudragit (EU), hydroxypropyl methylcellulose (HPMC), and Zeolite imidazolate frameworks (ZIF-8) nanoparticles. EU/HPMC/ZIF-8 nanofibers have presented a high capability of electron transfer, and more active surface area than bare SPCE due to synergistic effects between EU, HPMC, and ZIF-8. On the other hand, EU/HPMC nanofibers provided high porosity, flexible structures, high specific surface area, and good mechanical strength. The presence of ZIF-8 nanoparticles improved the immobilization of anti-c-MET on the modified SPCE and also resulted in increasing the conductivity. By c-MET incubation on the modified SPCE, c-MET was connected to anti-c-MET, and consequently the electrochemical signal of [Fe(CN)6]3-/4- as the anion redox probe was reduced. In order to investigate the structural and morphological characteristics and elemental composition of electrospun nanofibers, various characterization methods including FE-SEM, XRD, FTIR, and EDS were used. Under optimum conditions with a working potential range -0.3-0.6 V (vs. Ag/AgCl), linear range (LR), correlation coefficient (R2), sensitivity, and limit of detection (LOD) were acquired at 100 fg/mL-100 ng/mL, 0.9985, 53.28 µA/cm2.dec, and 1.28 fg/mL, respectively. Moreover, the mentioned biosensor was investigated in a human plasma sample to determine c-MET and showed ideal results including reproducibility, stability, and good selectivity against other proteins.


Asunto(s)
Biomarcadores de Tumor , Técnicas Biosensibles , Técnicas Electroquímicas , Nanofibras , Proteínas Proto-Oncogénicas c-met , Humanos , Biomarcadores de Tumor/sangre , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Imidazoles , Límite de Detección , Estructuras Metalorgánicas/química , Nanofibras/química , Nanopartículas/química , Neoplasias/sangre , Proteínas Proto-Oncogénicas c-met/sangre , Zeolitas/química
16.
Xenobiotica ; 43(8): 661-70, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23282065

RESUMEN

1. Flavonoids are a group of polyphenolic plant metabolites most commonly known for their antioxidant activities. They also show inhibitory activities on molybdo-flavoenzymes family of enzymes which are involved in biotransformation of some exogenous and endogenous chemicals. Most notably, aldehyde oxidase (AO), a member of this family, is responsible for metabolism of some therapeutic agents. On the other hand, there are some therapeutics which inhibit AO. As flavonoids are ubiquitous in human diet and have potential to interact with AO, it is important to investigate their effects at the molecular details. 2. The inhibitory effects of 15 flavonoids on the activity of rat liver AO were assessed. Quantitative structure-activity relationship studies were performed using genetic algorithm coupled partial least square and stepwise multiple linear regression methods to elucidate the important structural properties responsible for the observed inhibitory effects. To further understand the mode of interaction between these flavonoids and AO, a homology model of the enzyme was built and flavonoids were docked into its active site. The most important amino acids involved in the interactions were identified. 3. Quercetin, myricetin and genistein were the most potent inhibitors establishing favorable interactions with the enzyme. However, the glycosylated flavonoids showed relatively weaker inhibition which may be attributed to their hindered binding into the active site of AO by bulky sugar groups.


Asunto(s)
Aldehído Oxidasa/antagonistas & inhibidores , Flavonoides/química , Flavonoides/farmacología , Relación Estructura-Actividad Cuantitativa , Aldehído Oxidasa/química , Aldehído Oxidasa/metabolismo , Secuencia de Aminoácidos , Animales , Genisteína/química , Genisteína/farmacología , Humanos , Concentración 50 Inhibidora , Masculino , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Quercetina/química , Quercetina/farmacología , Ratas , Ratas Sprague-Dawley , Alineación de Secuencia
17.
Talanta ; 265: 124844, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37352780

RESUMEN

A novel electrochemical immunosensor was developed for ultrasensitive determination of the hormone insulin-like growth factor 1 (IGF-1) based on immobilization of a specific monoclonal antibody on the electrospun nanofibers of Polyacrylonitrile (PAN)/Zein-reduced graphene oxide (rGO) nanoparticle. The nanofibers deposited on glassy carbon electrode (GCE) showed good electrochemical behaviors with synergistic effects between PAN, Zein, and rGO. PAN/Zein nanofibers were used due to flexibility, high porosity, good mechanical strength, high specific surface area, and flexible structures, while rGO nanoparticles were used to improve the detection sensitivity and anti-IGF-1 immobilizing. Different characterization techniques were applied consisting of FE-SEM, FT-IR, and EDS for the investigation of morphological features and nanofiber size. The redox reactions of [Fe(CN)6]4-/3- on the modified electrode surface were probed for studying the immobilization and determination processes, using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Under optimal conditions, LOD (limit of detection) and LOQ (limit of quantification) were obtained as 55.72 fg/mL and 185.73 fg/mL respectively, and sensitivity was acquired 136.29 µA/cm2.dec. Moreover, a wide linear range was obtained ranging from 1 pg/mL to 10 ng/mL for IGF-1. Furthermore, the proposed method was applied for the analysis of IGF-1 in several human plasma samples with acceptable results, and it also exhibited high selectivity, stability, and reproducibility.


Asunto(s)
Técnicas Biosensibles , Grafito , Nanopartículas del Metal , Nanofibras , Zeína , Humanos , Factor I del Crecimiento Similar a la Insulina , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Inmunoensayo/métodos , Grafito/química , Electrodos , Nanopartículas del Metal/química
18.
J Biomater Sci Polym Ed ; 34(5): 695-714, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36745508

RESUMEN

Due to a lack of sufficient blood supply and unique physicochemical properties, the treatment of injured cartilage is laborious and needs an efficient strategy. Unfortunately, most of the current therapeutic approaches are, but not completely, unable to restore the function of injured cartilage. Tissue engineering-based modalities are an alternative option to reconstruct the injured tissue. Considering the unique structure and consistency of cartilage tissue (osteochondral junction), it is mandatory to apply distinct biomaterials with unique properties slightly different from scaffolds used for soft tissues. PCL is extensively used for the fabrication of fine therapeutic scaffolds to accelerate the restorative process. Thermosensitive PCL hydrogels with distinct chemical compositions have paved the way for sophisticated cartilage regeneration. This review aimed to collect recent findings regarding the application of PCL in hydrogels blended with natural, synthetic materials in the context of cartilage healing.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Hidrogeles/química , Cartílago , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/química , Andamios del Tejido/química
19.
Sci Rep ; 13(1): 16163, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37758805

RESUMEN

Alzheimer's disease (AD) is a progressive brain disorder characterized by the ongoing decline of brain functions. Studies have revealed the detrimental effects of hyperphosphorylated tau (p-tau) protein fibrils in AD pathogenesis, highlighting the importance of this factor in the early-stage detection of AD conditions. We designed an electrochemical immunosensor for quantitative detection of the cis conformation of the p-tau protein (cis-p-tau) employing platinum nanoparticles (Pt NPs) supported on zeolitic imidazolate frameworks (ZIF) for modifying the glassy carbon electrode (GCE) surface. Under optimum conditions, the immunosensor selectively and sensitively detected cis-p-tau within the broad linear range of 1 fg mL-1 to 10 ng mL-1 and the low limit of detection (LOD) of 1 fg mL-1 with desired reproducibility and stability. Furthermore, the fabricated immunosensor's performance was examined for the cis-p-tau analysis in the serum of AD patients, indicating its accuracy and feasibility for real-sample analysis. Notably, this is the first application of Pt@ZIF-8 nanocomposite in fabricating a valid immunosensor for selective cis-p-tau detection, even in the presence of trans-p-tau. It is worth mentioning that the enzyme-linked immunosorbent assay (ELISA) reference technique is not able to evaluate pico- or femtomolar concentrations of cis-p-tau, making the fabricated immunosensor superior for early-stage measurement and screening of AD.


Asunto(s)
Enfermedad de Alzheimer , Técnicas Biosensibles , Nanopartículas del Metal , Nanocompuestos , Zeolitas , Humanos , Enfermedad de Alzheimer/diagnóstico , Proteínas tau , Zeolitas/química , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Inmunoensayo , Platino (Metal)/química , Nanocompuestos/química , Técnicas Electroquímicas , Límite de Detección , Oro/química
20.
Bioimpacts ; 13(5): 405-413, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37736340

RESUMEN

Introduction: The inhibition of vascularization into tumor stroma as well as dynamic cell growth is the center of attention. Here, we aimed to examine the role of vandetanib on angiogenesis capacity of breast cancer stem cell (CSCs). Methods: MDA-MB-231 cells were exposed to different doses of vandetanib and survival rate was monitored. Stimulatory effects of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and epidermal growth factor (EGF) were evaluated in vandetanib-treated MDA-MB-231 cells. In vitro tubulogenesis capacity was studied on the Matrigel surface. The synergistic effects of vandetanib on cell survival were also assessed after PI3K and/or Wnt3a inhibition. Vascular endothelial (VE)-cadherin, matrix metalloproteinase-2 (MMP-2), -9, Wnt3a, and p-Akt/Akt ratio were measured using western blotting. Results: Vandetanib reduced survival rate in a dose-dependent manner (P<0.05). Proliferative effects associated with VEGF, FGF, and EGF were blunted in these cells pre-exposed to vandetanib (P<0.05). The microcirculation pattern's triple-negative breast cancer (TNBC) was suppressed by 1, 5 µM of vandetanib (P<0.05). Hence 1, 5 µM of vandetanib potentially decreased the population of CD24- cells. 1 and 5 µM of vandetanib inhibited cell proliferation by blocking PI3K and Wnt3a pathways and decreased the p-Akt/Akt ratio, Wnta3 protein levels (P<0.05). 1 and 5 µM vandetanib combined with PI3K inhibitor diminished metastatic markers including, MMP-2, and MMP-9. The concurrent treatment (PI3K, inhibitor+ 1, 5 µM vandetanib) also considerably reduced epithelial-mesenchymal transition (EMT) markers such as VE-cadherin (P<0.05). Conclusion: Vandetanib suppressed vasculogenic mimicry (VM) networking through blunting stemness properties, coincided with suppression of VE-cadherin in CSCs.

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