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Electroconductive polymers are the materials of interest for the fabrication of electro-conductive tissues. Metal ions through the redox systems offer polymers with electrical conductivity. In this study, we processed a gelatin methacrylate (GelMA) network with gold nanoparticles (GNPs) through a redox system with parahydroxybenzaldehyde (PHB) or curcumin to enhance its electrical conductivity. Induction of the redox system with both PHB and curcumin into the GelMA, introduced some new functional groups into the polymeric network, as it has been confirmed by H-NMR and FTIR. These new bonds resulted in higher electro-conductivity when GNPs were added to the polymer. Higher electroactivity was achieved by PHB compared to the curcumin-induced redox system, and the addition of GNPs without redox system induction showed the lowest electroactivity. MTT was used to evaluate the biocompatibility of the resultant polymers, and the PHB-treated hydrogels showed higher proliferative effects on the cells. The findings of this study suggest that the introduction of a redox system by PHB in the GelMA network along with GNPs can contribute to the electrochemical properties of the material. This electroactivity can be advantageous for tissue engineering of electro-conductive tissues like cardiac and nervous tissues.
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Benzaldeídos , Materiais Biocompatíveis , Curcumina , Condutividade Elétrica , Gelatina , Ouro , Hidrogéis , Nanopartículas Metálicas , Metacrilatos , Engenharia Tecidual , Gelatina/química , Ouro/química , Engenharia Tecidual/métodos , Nanopartículas Metálicas/química , Hidrogéis/química , Benzaldeídos/química , Curcumina/química , Curcumina/farmacologia , Metacrilatos/química , Materiais Biocompatíveis/química , Proibitinas , Espectroscopia de Infravermelho com Transformada de Fourier , Teste de Materiais , Animais , Humanos , Proliferação de Células/efeitos dos fármacos , Oxirredução , Alicerces Teciduais/químicaRESUMO
Chemotherapy is the first choice in the treatment of cancer and is always preferred to other approaches such as radiation and surgery, but it has never met the need of patients for a safe and effective drug. Therefore, new advances in cancer treatment are now needed to reduce the side effects and burdens associated with chemotherapy for cancer patients. Targeted treatment using nanotechnology are now being actively explored as they could effectively deliver therapeutic agents to tumor cells without affecting normal cells. Dendrimers are promising nanocarriers with distinct physiochemical properties that have received considerable attention in cancer therapy studies, which is partly due to the numerous functional groups on their surface. In this review, we discuss the progress of different types of dendrimers as delivery systems in cancer therapy, focusing on the challenges, opportunities, and functionalities of the polymeric molecules. The paper also reviews the various role of dendrimers in their entry into cells via endocytosis, as well as the molecular and inflammatory pathways in cancer. In addition, various dendrimers-based drug delivery (e.g., pH-responsive, enzyme-responsive, redox-responsive, thermo-responsive, etc.) and lipid-, amino acid-, polymer- and nanoparticle-based modifications for gene delivery, as well as co-delivery of drugs and genes in cancer therapy with dendrimers, are presented. Finally, biosafety concerns and issues hindering the transition of dendrimers from research to the clinic are discussed to shed light on their clinical applications.
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Dendrímeros , Nanopartículas , Neoplasias , Humanos , Dendrímeros/química , Dendrímeros/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Nanotecnologia , Neoplasias/tratamento farmacológicoRESUMO
Breast cancer is the most malignant tumor in women, and there is no absolute cure for it. Although treatment modalities including surgery, chemotherapy, and radiotherapy are utilized for breast cancer, it is still a life-threatening disease for humans. Nanomedicine has provided a new opportunity in breast cancer treatment, which is the focus of the current study. The nanocarriers deliver chemotherapeutic agents and natural products, both of which increase cytotoxicity against breast tumor cells and prevent the development of drug resistance. The efficacy of gene therapy is boosted by nanoparticles and the delivery of CRISPR/Cas9, Noncoding RNAs, and RNAi, promoting their potential for gene expression regulation. The drug and gene codelivery by nanoparticles can exert a synergistic impact on breast tumors and enhance cellular uptake via endocytosis. Nanostructures are able to induce photothermal and photodynamic therapy for breast tumor ablation via cell death induction. The nanoparticles can provide tumor microenvironment remodeling and repolarization of macrophages for antitumor immunity. The stimuli-responsive nanocarriers, including pH-, redox-, and light-sensitive, can mediate targeted suppression of breast tumors. Besides, nanoparticles can provide a diagnosis of breast cancer and detect biomarkers. Various kinds of nanoparticles have been employed for breast cancer therapy, including carbon-, lipid-, polymeric- and metal-based nanostructures, which are different in terms of biocompatibility and delivery efficiency.
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Neoplasias da Mama , Nanopartículas , Neoplasias , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Imunoterapia , Terapia Genética , Nanopartículas/química , Microambiente TumoralRESUMO
Oxidative damage and infection can prevent or delay tissue repair. Moreover, infection reinforces reactive oxygen species (ROS) formation, which makes the wound's condition even worse. Therefore, the need for antioxidant and antibacterial agents is felt for tissue regeneration. There are emerging up-and-coming biomaterials that recapitulate both properties into a package, offering an effective solution to turn the wound back into a healing state. In this article, the principles of antioxidant and antibacterial activity are summarized. The review starts with biological aspects, getting the readers to familiarize themselves with tissue barriers against infection. This is followed by the chemistry and mechanism of action of antioxidant and antibacterial materials (dual function). Eventually, the outlook and challenges are underlined to provide where the dual-function biomaterials are and where they are going in the future. It is expected that the present article inspires the designing of dual-function biomaterials to more advanced levels by providing the fundamentals and comparative points of view and paving the clinical way for these materials.
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Antibacterianos , Antioxidantes , Antibacterianos/química , Antioxidantes/farmacologia , Antioxidantes/química , Cicatrização , Estresse Oxidativo , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/químicaRESUMO
Wound healing is a complex process that often requires intervention to accelerate tissue regeneration and prevent complications. The goal of this research was to assess the potential of bioactive chitosan@poly (ethylene oxide)@CuFe2O4 (CS@PEO@CF) nanofibers for wound healing applications by evaluating their morphology, mechanical properties, and magnetic behavior. Additionally, in vitro and in vivo studies were conducted to investigate their effectiveness in promoting wound healing treatment. The nanoparticles exhibited remarkable antibacterial and antioxidant properties. In the nanofibrous mats, the optimal concentration of CuFe2O4 was determined to be 0.1% Wt/V. Importantly, this concentration did not adversely affect the viability of fibroblast cells, which also identified the ideal concentration. The scaffold's hemocompatibility revealed nonhemolytic properties. Additionally, a wound-healing experiment demonstrated significant migration and growth of fibroblast cells at the edge of the wound. These nanofibrous mats are applied to treat rats with full-thickness excisional wounds. Histopathological analysis of these wounds showed enhanced wound healing ability, as well as regeneration of sebaceous glands and hair follicles within the skin. Overall, the developed wound dressing comprises CuFe2O4 nanoparticles incorporated into CS/PEO nanofibrous mats demonstrating its potential for successful application in wound treatment.
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Quitosana , Nanofibras , Ratos , Animais , Quitosana/farmacologia , Óxido de Etileno , Cicatrização , Antibacterianos/farmacologiaRESUMO
Viruses are a major cause of mortality and socio-economic downfall despite the plethora of biopharmaceuticals designed for their eradication. Conventional antiviral therapies are often ineffective. Live-attenuated vaccines can pose a safety risk due to the possibility of pathogen reversion, whereas inactivated viral vaccines and subunit vaccines do not generate robust and sustained immune responses. Recent studies have demonstrated the potential of strategies that combine nanotechnology concepts with the diagnosis, prevention, and treatment of viral infectious diseases. The present review provides a comprehensive introduction to the different strains of viruses involved in respiratory diseases and presents an overview of recent advances in the diagnosis and treatment of viral infections based on nanotechnology concepts and applications. Discussions in diagnostic/therapeutic nanotechnology-based approaches will be focused on H1N1 influenza, respiratory syncytial virus, human parainfluenza virus type 3 infections, as well as COVID-19 infections caused by the SARS-CoV-2 virus Delta variant and new emerging Omicron variant.
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COVID-19 , Vírus da Influenza A Subtipo H1N1 , Nanoestruturas , Pneumonia , Viroses , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/prevenção & controle , Nanoestruturas/uso terapêutico , Teste para COVID-19RESUMO
BACKGROUND: Skin, the first barrier to pathogens, loses its integrity and function after an injury. The presence of an antibacterial dressing at the wound site may prevent bacterial invasion and also improve the healing process. OBJECTIVES: The current study aimed to fabricate a biomimetic membrane with antibacterial properties for healing chronic wounds. MATERIAL AND METHODS: The membranes, fabricated through electrospinning, are comprised of poly(ethylene oxide) (PEO) and zinc oxide nanoparticles (ZnO-NPs) as the main biomaterial and antibacterial agent, respectively. Antibacterial activity, cell attachment and viability were tested to evaluate the biological properties of the membranes. The optimal cell compatible concentration of ZnO-NPs was determined for further studies. In vitro characterization of the membranes was performed to confirm their suitable properties for wound healing. RESULTS: The antibacterial PEO/ZnO-NP membrane containing 2% of nanoparticles showed no cell toxicity, and human fibroblast cells were able to adhere and proliferate on the scaffold. The in vitro results from the tensile test, wettability, porosity, and protein adsorption revealed appropriate properties of the membrane as a scaffold for skin tissue engineering. CONCLUSIONS: Synthetic polymers have been widely used for tissue engineering applications. The proper characteristics of PEO nanofibers, including a high ratio of surface/volume, moderate hydrophilicity and good mechanical properties, make this polymer interesting for skin regeneration. The results demonstrate the potential of the antibacterial PEO/ZnO-NP membrane to be used as an engineered scaffold to improve the wound healing process.
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Quitosana , Nanofibras , Polietilenoglicóis , Alicerces Teciduais , Óxido de Zinco , Antibacterianos/uso terapêutico , Células Cultivadas , Etilenos , Fibroblastos/citologia , Humanos , CicatrizaçãoRESUMO
Almost all cell types, either in vivo or in vitro, create extracellular vesicles (EVs). Among them are exosomes (EXOs), i.e., tiny nanovesicles containing a lipid bilayer, proteins, and RNAs that are actively involved in cellular communication, indicating that they may be exploited as both diagnostics and therapeutics for conditions like cancer. These nanoparticles can also be used as nanocarriers in many types of research to carry agents such as drugs. Plant-derived exosome-like nanoparticles (PENs) are currently under investigation as a substitute for EXOs formed from mammalian cells, allowing researchers to get beyond the technical constraints of mammalian vesicles. Because of their physiological, chemical, and biological properties, PENs have a lot of promise for use as nanocarriers in drug delivery systems that can deliver various dosages, especially when it comes to large-scale repeatability. The present study has looked at the origins and isolation techniques of PENs, their anticancer properties, their usage as nanocarriers in the treatment of different illnesses, and their antioxidant properties. These nanoparticles can aid in the achievement of therapeutic objectives, as they have benign, non-immunogenic side effects and can pass biological barriers. Time-consuming and perhaps damaging PEN separation techniques is used. For the current PEN separation techniques to be used in commercial and therapeutic settings, they must be altered. In this regard, the concurrent application of biological sciences can be beneficial for improving PEN separation techniques. PENs' innate metabolic properties provide them a great deal of promise for application in drug delivery systems. However, there could be a risk to both the loaded medications and the intrinsic bioactive components if these particles are heavily armed with drugs. Therefore, to prevent these side effects, more studies are needed to devise sophisticated drug-loading procedures and to learn more about the physiology of PENs.
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Exossomos , Vesículas Extracelulares , Neoplasias , Animais , Exossomos/metabolismo , Engenharia Tecidual , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , MamíferosRESUMO
Chitosan, a versatile amino polysaccharide biopolymer derived from chitin, exhibits broad-spectrum antimicrobial activity against various pathogenic microorganisms, including gram-negative and gram-positive bacteria, as well as fungi. Due to its ubiquitous use in medications, food, cosmetics, chemicals, and crops, it is an effective antibacterial agent. However, the antimicrobial performance of chitosan is influenced by multiple factors, which have been extensively investigated and reported in the literature. The goal of this review paper is to present a thorough grasp of the mechanisms of action and determining variables of chitosan and its derivatives' antibacterial activity. The article begins by providing a brief background on chitosan and its antimicrobial properties, followed by the importance of understanding the mechanism of action and factors influencing its activity".
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Anti-Infecciosos , Quitosana , Quitosana/química , Quitosana/farmacologia , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Fungos/efeitos dos fármacos , Bactérias/efeitos dos fármacos , HumanosRESUMO
An optimal tissue-engineered dermal substitute should possess biocompatibility and cell adhesion conduction to facilitate fibroblast and keratinocyte infiltration and proliferation, as well as angiogenesis potential to escalate wound healing. Zinc was doped to bioactive glass-ceramic (Zn-BGC) to promote biocompatibility and angiogenesis properties. Zn-BGC was then incorporated into a collagen (Col) and gelatin (Gel) porous scaffold. The bioactive porous bionanocomposite exhibited biocompatibility along with improved cell attachment and proliferation. Scaffolds including Col-Gel/Zn-BGC with or without mouse embryonic fibroblasts were applied on full-thickness skin wounds on the BALB/c mice to assess their wound healing potential in vivo. The results indicated that the biodegradation rate of the Col-Gel/Zn-BGC nanocomposites was comparable to the rate of skin tissue regeneration in vivo. Macroscopic wound healing results showed that Col-Gel/Zn-BGC loaded with mouse embryonic fibroblast possesses the smallest wound size, indicating the fastest healing process. Histopathological evaluations displayed that the optimal wound regeneration was observed in Col-Gel/Zn-BGC nanocomposites loaded with mouse embryonic fibroblasts indicated by epithelialization and angiogenesis; besides the number of fibroblasts and hair follicles was increased. The bioactive nanocomposite scaffold of Col-Gel containing Zn-BGC nanoparticles loaded with mouse embryonic fibroblasts can be employed as a desirable skin substitute to ameliorate cutaneous wound regeneration.
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MicroRNAs (miRNAs) as therapeutic agents have attracted increasing interest in the past decade owing to their significant effectiveness in treating a wide array of ailments. These polymerases II-derived noncoding RNAs act through post-transcriptional controlling of different proteins and their allied pathways. Like other areas of medicine, researchers have utilized miRNAs for managing acute and chronic wounds. The increase in the number of patients suffering from either under-healing or over-healing wound demonstrates the limited efficacy of the current wound healing strategies and dictates the demands for simpler approaches with greater efficacy. Various miRNA can be designed to induce pathway beneficial for wound healing. However, the proper design of miRNA and its delivery system for wound healing applications are still challenging due to their limited stability and intracellular delivery. Therefore, new miRNAs are required to be identified and their delivery strategy needs to be optimized. In this review, we discuss the diverse roles of miRNAs in various stages of wound healing and provide an insight on the most recent findings in the nanotechnology and biomaterials field, which might offer opportunities for the development of new strategies for this chronic condition. We also highlight the advances in biomaterials and delivery systems, emphasizing their challenges and resolutions for miRNA-based wound healing. We further review various biovectors (e.g., adenovirus and lentivirus) and abiotic materials such as organic and inorganic nanomaterials, along with dendrimers and scaffolds, as the delivery systems for miRNA-based wound healing. Finally, challenges and opportunities for translation of miRNA-based strategies into clinical applications are discussed.
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A proper self-regenerating capability is lacking in human cardiac tissue which along with the alarming rate of deaths associated with cardiovascular disorders makes tissue engineering critical. Novel approaches are now being investigated in order to speedily overcome the challenges in this path. Tissue engineering has been revolutionized by the advent of nanomaterials, and later by the application of carbon-based nanomaterials because of their exceptional variable functionality, conductivity, and mechanical properties. Electrically conductive biomaterials used as cell bearers provide the tissue with an appropriate microenvironment for the specific seeded cells as substrates for the sake of protecting cells in biological media against attacking mechanisms. Nevertheless, their advantages and shortcoming in view of cellular behavior, toxicity, and targeted delivery depend on the tissue in which they are implanted or being used as a scaffold. This review seeks to address, summarize, classify, conceptualize, and discuss the use of carbon-based nanoparticles in cardiac tissue engineering emphasizing their conductivity. We considered electrical conductivity as a key affecting the regeneration of cells. Correspondingly, we reviewed conductive polymers used in tissue engineering and specifically in cardiac repair as key biomaterials with high efficiency. We comprehensively classified and discussed the advantages of using conductive biomaterials in cardiac tissue engineering. An overall review of the open literature on electroactive substrates including carbon-based biomaterials over the last decade was provided, tabulated, and thoroughly discussed. The most commonly used conductive substrates comprising graphene, graphene oxide, carbon nanotubes, and carbon nanofibers in cardiac repair were studied.
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Pancreatic cancer is one of the harshest and most challenging cancers to treat, often labeled as incurable. Chemotherapy continues to be the most popular treatment yet yields a very poor prognosis. The main barriers such as inefficient drug penetration and drug resistance, have led to the development of drug carrier systems. The benefits, ease of fabrication and modification of liposomes render them as ideal future drug delivery systems. This review delves into the versatility of liposomes to achieve various mechanisms of treatment for pancreatic cancer. Not only are there benefits of loading chemotherapy drugs and targeting agents onto liposomes, as well as mRNA combined therapy, but liposomes have also been exploited for immunotherapy and can be programmed to respond to photothermal therapy. Multifunctional liposomal formulations have demonstrated significant pre-clinical success. Functionalising drug-encapsulated liposomes has resulted in triggered drug release, specific targeting, and remodeling of the tumor environment. Suppressing tumor progression has been achieved, due to their ability to more efficiently and precisely deliver chemotherapy. Currently, no multifunctional surface-modified liposomes are clinically approved for pancreatic cancer thus we aim to shed light on the trials and tribulations and progress so far, with the hope for liposomal therapy in the future and improved patient outcomes. STATEMENT OF SIGNIFICANCE: Considering that conventional treatments for pancreatic cancer are highly associated with sub-optimal performance and systemic toxicity, the development of novel therapeutic strategies holds outmost relevance for pancreatic cancer management. Liposomes are being increasingly considered as promising nanocarriers for providing not only an early diagnosis but also effective, highly specific, and safer treatment, improving overall patient outcome. This manuscript is the first in the last 10 years that revises the advances in the application of liposome-based formulations in bioimaging, chemotherapy, phototherapy, immunotherapy, combination therapies, and emergent therapies for pancreatic cancer management. Prospective insights are provided regarding several advantages resulting from the use of liposome technology in precision strategies, fostering new ideas for next-generation diagnosis and targeted therapies of pancreatic cancer.
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Antineoplásicos , Neoplasias Pancreáticas , Humanos , Lipossomos , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Portadores de Fármacos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias PancreáticasRESUMO
Urological cancers are among the most common malignancies around the world. In particular, bladder cancer severely threatens human health due to its aggressive and heterogeneous nature. Various therapeutic modalities have been considered for the treatment of bladder cancer although its prognosis remains unfavorable. It is perceived that treatment of bladder cancer depends on an interdisciplinary approach combining biology and engineering. The nanotechnological approaches have been introduced in the treatment of various cancers, especially bladder cancer. The current review aims to emphasize and highlight possible applications of nanomedicine in eradication of bladder tumor. Nanoparticles can improve efficacy of drugs in bladder cancer therapy through elevating their bioavailability. The potential of genetic tools such as siRNA and miRNA in gene expression regulation can be boosted using nanostructures by facilitating their internalization and accumulation at tumor sites and cells. Nanoparticles can provide photodynamic and photothermal therapy for ROS overgeneration and hyperthermia, respectively, in the suppression of bladder cancer. Furthermore, remodeling of tumor microenvironment and infiltration of immune cells for the purpose of immunotherapy are achieved through cargo-loaded nanocarriers. Nanocarriers are mainly internalized in bladder tumor cells by endocytosis, and proper design of smart nanoparticles such as pH-, redox-, and light-responsive nanocarriers is of importance for targeted tumor therapy. Bladder cancer biomarkers can be detected using nanoparticles for timely diagnosis of patients. Based on their accumulation at the tumor site, they can be employed for tumor imaging. The clinical translation and challenges are also covered in current review.
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Green chemistry has been a growing multidisciplinary field in recent years showing great promise in biomedical applications, especially for cancer therapy. Chitosan (CS) is an abundant biopolymer derived from chitin and is present in insects and fungi. This polysaccharide has favorable characteristics, including biocompatibility, biodegradability, and ease of modification by enzymes and chemicals. CS-based nanoparticles (CS-NPs) have shown potential in the treatment of cancer and other diseases, affording targeted delivery and overcoming drug resistance. The current review emphasizes on the application of CS-NPs for the delivery of a chemotherapeutic agent, doxorubicin (DOX), in cancer therapy as they promote internalization of DOX in cancer cells and prevent the activity of P-glycoprotein (P-gp) to reverse drug resistance. These nanoarchitectures can provide co-delivery of DOX with antitumor agents such as curcumin and cisplatin to induce synergistic cancer therapy. Furthermore, co-loading of DOX with siRNA, shRNA, and miRNA can suppress tumor progression and provide chemosensitivity. Various nanostructures, including lipid-, carbon-, polymeric- and metal-based nanoparticles, are modifiable with CS for DOX delivery, while functionalization of CS-NPs with ligands such as hyaluronic acid promotes selectivity toward tumor cells and prevents DOX resistance. The CS-NPs demonstrate high encapsulation efficiency and due to protonation of amine groups of CS, pH-sensitive release of DOX can occur. Furthermore, redox- and light-responsive CS-NPs have been prepared for DOX delivery in cancer treatment. Leveraging these characteristics and in view of the biocompatibility of CS-NPs, we expect to soon see significant progress towards clinical translation.
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Driven by regulatory authorities and the ever-growing demands from industry, various artificial tissue models have been developed. Nevertheless, there is no model to date that is capable of mimicking the biomechanical properties of the skin whilst exhibiting the hydrophilicity/hydrophobicity properties of the skin layers. As a proof-of-concept study, tissue surrogates based on gel and silicone are fabricated for the evaluation of microneedle penetration, drug diffusion, photothermal activity, and ultrasound bioimaging. The silicone layer aims to imitate the stratum corneum while the gel layer aims to mimic the water-rich viable epidermis and dermis present in in vivo tissues. The diffusion of drugs across the tissue model is assessed, and the results reveal that the proposed tissue model shows similar behavior to a cancerous kidney. In place of typical in vitro aqueous solutions, this model can also be employed for evaluating the photoactivity of photothermal agents since the tissue model shows a similar heating profile to skin of mice when irradiated with near-infrared laser. In addition, the designed tissue model exhibits promising results for biomedical applications in optical coherence tomography and ultrasound imaging. Such a tissue model paves the way to reduce the use of animals testing in research whilst obviating ethical concerns.
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Epiderme , Pele , Animais , Camundongos , Pele/diagnóstico por imagem , Ultrassonografia/métodos , Silicones/químicaRESUMO
Bacterial wound infection is one of the most common nosocomial infections. The unnecessary employment of antibiotics led to raising the growth of antibiotic-resistant bacteria. Accordingly, alternative armaments capable of accelerating wound healing along with bactericidal effects are urgently needed. Considering this, we fabricated chitosan (CS)/polyethylene oxide (PEO) nanofibers armed with antibacterial silver and zinc oxide nanoparticles. The nanocomposites exhibited a high antioxidant effect and antibacterial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Besides, based on the results of the cell viability assays, the optimum concentration of ZnONPs and AgNPs in the nanofibrous mats is 0.2% w/v and 0.08% w/v respectively and had no cytotoxicity on fibroblast cells. The scaffold also showed good blood compatibility according to the effects of coagulation time. As well as significant fibroblast migration and proliferation on the wound margin, according to wound-healing assay. All in all, the developed biocompatible, antioxidant, and antibacterial Ag-ZnO NPs incorporated CS/PEO nanofibrous mats showed their potential as an effective wound dressing.
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In this work, magnetic poly(aniline-co-melamine) nanocomposite as an efficient heterogeneous polymer-based nanocatalyst was fabricated in two steps. First, poly(aniline-co-melamine) was synthesized through the chemical oxidation by ammonium persulfate, then the magnetic nanocatalyst was successfully prepared from the in-situ coprecipitation method in the presence of poly(aniline-co-melamine). The resulting poly(aniline-co-melamine)@MnFe2O4 was characterized by FTIR, FESEM, XRD, VSM, EDX, TGA, and UV-vis analyses. The catalytic activity of poly(aniline-co-melamine)@MnFe2O4 was investigated in the synthesis of 4,4'-(arylmethylene)bis(1H-pyrazole-5-ol) derivatives, and new alkylene bridging bis 4,4'-(arylmethylene)bis(1H-pyrazole-5-ol) derivatives in excellent yields. The yield of 1,4-dihydropyrano[2,3-c]pyrazoles, 4,4'-(arylmethylene)bis(1H-pyrazol-5-ol), yields, and new alkylene bridging bis 4,4'-(arylmethylene)bis(1H-pyrazol-5-ol) derivatives were obtained 89%-96%, 90%-96%, and 92%-96%, respectively. The poly(aniline-co-melamine)@MnFe2O4 nanocatalyst can be recycled without pre-activation and reloaded up to five consecutive runs without a significant decrease in its efficiency. In addition, the antioxidant activity of some derivatives was evaluated by DPPH assay. Results showed that the maximum antioxidant activity of 4,4'-(arylmethylene)bis(1H-pyrazole-5-ol) derivatives and 1,4-dihydropyrano[2,3-c]pyrazoles were 75% and 90%, respectively. Furthermore, 4,4'-(arylmethylene)bis(1H-pyrazole-5-ol) derivatives and 1,4-dihydropyrano[2,3-c]pyrazoles showed good potential for destroying colon cancer cell lines. Consequently, the poly(aniline-co-melamine)@MnFe2O4 nanocomposite is an excellent catalyst for green chemical processes owing to its high catalytic activity, stability, and reusability.
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Repairing of large bone injuries is an important problem in bone regeneration field. Thus, developing new therapeutic approaches such as tissue engineering using 3D scaffolds is necessary. Incorporation of some bioactive materials and trace elements can improve scaffold properties. We made chitosan/alginate/strontium-doped bioglass composite scaffolds with optimized properties for bone tissue engineering. Bioglass (BG) and Sr-doped bioglasses (Sr-BG) were synthesized using Sol-Gel method. Alginate-Chitosan (Alg/Cs) scaffold and scaffolds containing different ratio (10%, 20% and 30%) of BG (Alg/Cs/BG10, 20, 30) or Sr-BG (Alg/Cs/Sr-BG10, 20, 30) were fabricated using freeze drying method. Characterization of bioglasses/scaffolds was done using zeta sizer, FTIR, XRD, (FE) SEM and EDS. Also, mechanical strength, antibacterial effect degradation and swelling profile of scaffolds were evaluated. Bone differentiation efficiency and viability of MSCs on scaffolds were determined by Alizarin Red, ALP and MTT methods. Cell toxicity and antibacterial effect of bioglasses were determined using MTT, MIC and MBC methods. Incorporation of BG into Alg/Cs scaffolds amplified biomineralization and mechanical properties along with improved swelling ratio, degradation profile and cell differentiation. Mechanical strength and cell differentiation efficiency of Alg/Cs/BG20 scaffold was considerably higher than scaffolds with lower or higher BG concentrations. Alg/Cs/Sr-BG scaffolds had higher mechanical stability and more differentiation efficiency in comparison with Alg/Cs and Alg/Cs/BG scaffolds. Also, Mechanical strength and cell differentiation efficiency of Alg/Cs/Sr-BG20 scaffold was considerably higher than scaffolds with various Sr-BG concentrations. Biomineralization of Alg/Cs/BG scaffolds slightly was higher than Alg/Cs/Sr-BG scaffolds. Overall, we concluded that Alg/Cs/Sr-BG20 scaffolds are more suitable for repairing bone major injuries.
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Quitosana , Hidrogéis , Alginatos/farmacologia , Antibacterianos/farmacologia , Regeneração Óssea , Proliferação de Células , Cerâmica , Quitosana/farmacologia , Hidrogéis/farmacologia , Estrôncio/farmacologia , Engenharia Tecidual/métodos , Alicerces TeciduaisRESUMO
Over the past few decades, gold nanomaterials have shown great promise in the field of nanotechnology, especially in medical and biological applications. They have become the most used nanomaterials in those fields due to their several advantageous. However, rod-shaped gold nanoparticles, or gold nanorods (GNRs), have some more unique physical, optical, and chemical properties, making them proper candidates for biomedical applications including drug/gene delivery, photothermal/photodynamic therapy, and theranostics. Most of their therapeutic applications are based on their ability for tunable heat generation upon exposure to near-infrared (NIR) radiation, which is helpful in both NIR-responsive cargo delivery and photothermal/photodynamic therapies. In this review, a comprehensive insight into the properties, synthesis methods and toxicity of gold nanorods are overviewed first. For the main body of the review, the therapeutic applications of GNRs are provided in four main sections: (i) drug delivery, (ii) gene delivery, (iii) photothermal/photodynamic therapy, and (iv) theranostics applications. Finally, the challenges and future perspectives of their therapeutic application are discussed.