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This study aimed to construct a nanofibrous wound dressing composed of polyvinyl alcohol (PVA) and chitosan (CS) containing curcumin and Glycyrrhiza glabra root extract to inhibit infection and accelerate wound healing. Loading 10 wt% of G. glabra extract-curcumin (50:50) by electrospinng technique resulted in the formation of nanofibers (NFs) with diameter distribution 303 ± 38 and had a uniform and defect-free morphology. FTIR analysis confirmed the loading of the components without adverse interactions. Also, the results showed extremely high porosity, extraordinary liquid absorption capacity, and complete wettability. In addition, G. glabra extract-curcumin showed significant antioxidant activity and their release profile from NFs was continuous and sustained. Also, the prepared NF could inhibit the growth of both Gram-positive Saureus and Gram-negative E. coli strains. Wound healing evaluation in the infected animal model showed that the NFs caused full wound closure and accelerated skin regeneration. The studies on inhibiting the bacteria growth at the wound site also revealed complete inhibitory effects. Moreover, histopathology studies confirmed the complete regeneration of skin layers, formation of collagen fibers, and angiogenesis. Finally, PVA/CS NFs containing G. glabra extract-curcumin as a multifunctional bioactive wound dressing presented a promising approach for promoting the healing of infected wounds.
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Antibacterianos , Bandagens , Quitosana , Curcumina , Escherichia coli , Nanofibras , Extratos Vegetais , Álcool de Polivinil , Cicatrização , Curcumina/farmacologia , Curcumina/química , Curcumina/administração & dosagem , Cicatrização/efeitos dos fármacos , Nanofibras/química , Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Quitosana/química , Álcool de Polivinil/química , Escherichia coli/efeitos dos fármacos , Glycyrrhiza/química , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Masculino , Antioxidantes/farmacologia , Antioxidantes/química , Camundongos , RatosRESUMO
Infections are severe complications associated with chronic wounds and tardy healing that should be timely treated to achieve rapid and proper tissue repair. To hinder such difficulties, a nanofibrous mat composed of polyvinyl alcohol and chitosan (PVA/CS) was developed by electrospinning method, containing thyme (Thymus vulgaris) and ginger (Zingiber officinale) extracts. The mat containing 10 wt% of the extracts (at the ratio of 50:50) exposed the nanofibers (NFs) with the nanoscale diameter (average 382 ± 60 nm), smooth surface, and defect-free morphology. Likewise, the relevant analyses of the loaded mat displayed high wettability, porosity, and liquid absorption capacity without any adverse interaction. The obtained mat also provided a high antioxidant activity, and its release profile was continuous and sustained for nearly 72 h. Besides, it inhibited the growth of both Gram-positive S. aureus and Gram-negative E. coli strains. Furthermore, the proposed mat significantly accelerated cutaneous wound healing in bacterial-infected rats by preventing bacteria growth at the wound site. At last, histopathology analysis confirmed the ample regeneration of skin structures, forming collagen fibers and appendages. Overall, the proposed mat containing ginger-thyme extracts provides multiple therapeutic capabilities with promising solutions for inhibiting wound infection and accelerating the healing process.
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Complex interrelationships may exist among different types of frailty. This study aimed to evaluate the demographic and biological factors that influence the different types of frailty in community-dwelling older adults in Iran through a cross-sectional analysis of data obtained from the Birjand Longitudinal Aging Study. This study is an ongoing cohort study of people aged 60 years and over and employed a multistage stratified cluster random sampling. Anthropometric measures were obtained by nurses. The "Fried frailty phenotype" was defined as physical frailty. Cognitive frailty was assessed using the Mini-Mental State Examination. Social frailty was evaluated by some questions, and psychological frailty was assessed using a patient health questionnaire. Blood samples were taken after overnight fasting. All statistical analyses were performed using Stata12 (Texas, USA) and Python. Some type of frailty had been experienced by 62.27 % of the older adults. Cognitive frailty was the dominant type of frailty (55.69 %). Based on multivariate regression analysis, age, sex, education, and marital status were the influencing factors in all types of frailty. Network analysis revealed that physical, cognitive, psychological, and social frailty had synergistic effects on each other, and age and sex had dominant interactions with frailty types. Cognitive frailty was dominant compared with other types of frailty, indicating the need to detect cognitive frailty at the earliest stage and to implement an appropriate program to manage cognitive frailty in older adults.
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Fragilidade , Idoso , Humanos , Pessoa de Meia-Idade , Fragilidade/diagnóstico , Vida Independente , Idoso Fragilizado , Fatores Biológicos , Estudos de Coortes , Estudos Transversais , Envelhecimento , Avaliação Geriátrica , CogniçãoRESUMO
A cutaneous wound is caused by various injuries in the skin, which can be wrapped with an efficient dressing. Electrospinning is a straightforward adjustable technique that quickly and continuously generates nanofibrous wound dressings containing antibacterial and anti-inflammatory agents to promote wound healing. The present study investigated the physicochemical and biological properties of bromelain (BRO)- and silver nanoparticle (Ag NPs)-loaded gel-based electrospun polycaprolactone/chitosan (PCL/CS) nanofibrous dressings for wound-healing applications. Electron microscopy results showed that the obtained nanofibers (NFs) had a uniform and homogeneous morphology without beads with an average diameter of 176 ± 63 nm. The FTIR (Fourier transform infrared) analysis exhibited the loading of the components. Moreover, adding BRO and Ag NPs increased the tensile strength of the NFs up to 4.59 MPa. BRO and Ag NPs did not significantly affect the hydrophilicity and toxicity of the obtained wound dressing; however, the antibacterial activity against E. coli and S. aureus bacteria was significantly improved. The in vivo study showed that the wound dressing containing BRO and Ag NPs improved the wound-healing process within one week compared to other groups. Therefore, gel-based PCL/CS nanofibrous dressings containing BRO and Ag NPs could be a promising solution for healing skin wounds.
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Achillea wilhelmsii (A. wilhelmsii) contains several therapeutic phytochemicals, proposing a protective effect on inflammatory responses in autoimmune diseases such as ulcerative colitis (UC). However, its activities against UC encounter multiple obstacles. The current study aimed to formulate a colon-specific delivery of A. wilhelmsii for treating UC using chitosan nanoparticles (NPs) and Eudragit S100 as a mucoadhesive and pH-sensitive polymer, respectively. Core chitosan NP was loaded with A. wilhelmsii extract, followed by coating with Eudragit S100. Then, physicochemical characterizations of prepared NPs were conducted, and the anti-UC activity in the rat model was evaluated. The relevant physicochemical characterizations indicated the spherical NPs with an average particle size of 305 ± 34 nm and high encapsulation efficiency (88.6 ± 7.3%). The FTIR (Fourier transform infrared) analysis revealed the Eudragit coating and the extract loading, as well as the high radical scavenging ability of A. wilhelmsii was confirmed. The loaded NPs prevented the extract release in an acidic pH-mimicking medium and presented a complete release thereafter at a colonic pH. The loaded NPs markedly mitigated the induced UC lesions in rats, reflected by reducing inflammation, ulcer severity, and UC-related symptoms. Further, histopathological analysis exhibited reducing the extent of the inflammation and damage to colon tissue, and the determination of the involved pro-inflammatory cytokines in serum showed a significant reduction relative to free extract. The present results show that chitosan NPs containing A. wilhelmsii extract coated with Eudragit having proper physicochemical properties and substantial anti-inflammatory activity can significantly improve colonic lesions caused by UC.
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Achillea , Quitosana , Colite Ulcerativa , Colite , Nanopartículas , Ratos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Achillea/química , Colo , Nanopartículas/química , Inflamação/patologia , Colite/induzido quimicamente , Colite/tratamento farmacológicoRESUMO
Ginger is an anti-inflammatory and antioxidant natural substance, however, its effectiveness is limited primarily due to insufficient solubility and low oral bioavailability. This study aimed to formulate ginger extract into nanoemulsion (NE) to enhance therapeutic benefits against rheumatoid arthritis (RA). Hence, ginger extract-loaded NEs were prepared by the spontaneous emulsification method. The NE that passed the thermodynamic stability analyses showed no phase changes or appearance of turbidity. They had an average droplet diameter of 76 ± 45 nm with a zeta potential of - 35 ± 12 mV. Besides, the high antioxidant activities (IC50 = 53.89 µg/mL), about ten times increment of the skin permeability, and no sign of skin irritancy were observed from the ginger-loaded NE. The anti-arthritic evaluations of RA-induced rats treated with ginger-loaded NE showed a significant decline in arthritic symptoms and the highest rate of paw edema inhibition (27.7 %). In addition, the level of involved inflammatory cytokines in the serum of rats was significantly reduced (p < 0.05) compared to the negative control, so that histopathological manifestations also approved the reduction of inflammation indications. Thus, the topical delivery of ginger-loaded NE can be an efficient approach for reducing inflammation and inhibit of RA symptoms.
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Antioxidantes , Artrite Reumatoide , Ratos , Animais , Ratos Wistar , Emulsões/farmacologia , Artrite Reumatoide/tratamento farmacológico , InflamaçãoRESUMO
Skin rash is one of the most common complications during childhood. Viral agents play an essential role in the development of such symptoms. Present study aims to determine the prevalence and genetic variability of Human Herpesvirus 6 and 7 (HHV-6 and HHV-7) infections and their subtypes in children under 5 years of age with skin rash and negative for rubella and measles. We used serum and throat swap samples from 196 children with skin rash and fever. ELISA and IFA tests were performed to detect antibodies against HHV6/7. Sequencing was performed using Sanger sequencing, and BioEdit and MEGA10 software were used for sequence analysis. According to the results, 66% and 40% of cases were positive for HHV-6 IgM and HHV-7 IgM, respectively. According to the molecular analysis, HHV-6 Nested-PCR was positive in 18% of cases, however, HHV-7 Nested-PCR was positive in 7.7% of cases. On the other hand, HHV-6 IgG and HHV-7 IgG were positive in 91% and 55% of study cases, respectively. For HHV-6, we found some genetic variabilities resulting in antigenic changes compared to reference strains. HHV-7 isolates showed no genetic differentiation and had a stable gene sequence. Based on the results, the detection of some cases of HHV6/7 primary infection and the presence of specific symptoms of roseola in the study population needs continuous evaluation of HHV6/7 frequency and distribution, also genetic variabilities of HHV6. This can pave the way for investigating HHV6 immune evasion and vaccine research and studying the relationship between viral genetic variations and other factors like disease severity. Furthermore, it is necessary to determine the relation between HHV6 genetic changes and latent infection to be considered in possible future vaccines and antiviral drug development.
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Exantema , Infecções por Herpesviridae , Herpesvirus Humano 6 , Herpesvirus Humano 7 , Infecções por Roseolovirus , Criança , Humanos , Pré-Escolar , Herpesvirus Humano 7/genética , Exantema/epidemiologia , Infecções por Roseolovirus/epidemiologia , Anticorpos Antivirais , Imunoglobulina M , Febre , Imunoglobulina GRESUMO
Nano-based systems provide many advantages, including eluding gastrointestinal and first-pass metabolism of the drug and improving the potential advantage of reduced doses of drugs for an equal or better therapeutic effect compared to other parts of oral administration. Over the last few years, protein-based nanofibrous biomaterials have been used for better controlling dementia. PubMed, Scopus, and ISI Web of Science were consulted for available articles on nano-based fibrous systems for the treatment and diagnosis of dementia (up to October 2022). Of 725 articles that were identified and evaluated, only 19 were included. Eleven studies evaluated nanofibrous electrospun biomaterials for better dementia control. Among these, four investigated marker/biomarker detection for the early diagnosis of dementia. Two from four studies conducted hydrogel-based nanofibrous for Alzheimer's disease (AD) treatment. Additionally, four studies inspected stem cell (SC) transplantation on nano-based fibrous scaffolds for better treatment of dementia. Finally, two from the final four studies considered nano-based fibrous systems for the enhanced treatment of dementia. Our study concluded that nano-based fibrous platforms, exclusively peptide/protein-based nanofibrous scaffolds made from biomaterials, can be applied for dementia management by either diagnostic or therapeutic approaches specific in purpose-designed electrospun nanofibrous scaffolds.
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Doença de Alzheimer , Materiais Biocompatíveis , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , PeptídeosRESUMO
Impaired wound healing is a severe complication of sufferers, related to prolonged wound closure, a high infection rate, and eventually disabilities of organs. To aid resolve this issue, we developed the electrospun polyvinyl alcohol and chitosan (PVA/CS) nanofibrous scaffold-loaded flaxseed extract. The scaffold containing 10 wt% of the extract indicated a three-dimensional cross-network with a nano-scale diameter (257 ± 37 nm) and smooth surface. Also, the relevant analyses confirmed high water absorption, porosity, and wettability of the scaffold. Fourier-transform infrared (FTIR), degradation, and mechanical studies revealed the intact presence and loading of the extract into the scaffold, the complete degradation over 48 h, and a high tensile elastic modulus. Besides, the advanced scaffold displayed remarkable anti-oxidant and could inhibit the growth of both Gram-positive and negative bacteria compared to the free PVA/CS scaffold. Desired fibroblast viability and blood compatibility of flaxseed-loaded scaffold endorsed the biocompatibility for wound zones. The in vitro studies showed that the flaxseed-loaded scaffold resulted in an accelerated wound healing process and 100 % closure of the scratched area within 48 h. The results obtained reveal that the flaxseed-loaded PVA/CS electrospun scaffold could be effectively applied for wound healing promotion.
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Quitosana , Linho , Nanofibras , Álcool de Polivinil , CicatrizaçãoRESUMO
In recent years, three key techniques including random co-immobilization, positional co-immobilization, and compartmentalization for multi-enzyme immobilization were extensively considered. Herein, we investigate random co-immobilization and positional co-immobilization techniques for multi-enzyme systems in detail. We describe randomly co-immobilized glucose oxidase (GOx) and horseradish peroxidase (HRP) on reduced graphene oxide (rGO) as the most used methods. Materials and methods are presented in terms of preparation of GO and rGO as well as enzyme immobilization procedure. Moreover, the principles of positional co-immobilization have been reviewed, and the relevant methods based on microfluidic systems and DNA structure considering HRP and GOx enzymes have been individually studied. It is believed that the benefits of using the methods associated with random and specifically positional immobilized multi-enzyme systems include not only enhanced cascade enzymatic activity via manipulated surface such as microfluidic systems (including porous materials) and DNA structure but also improved enzyme stability and ease of recovery for recycle.
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Enzimas Imobilizadas , Glucose Oxidase , Estabilidade Enzimática , Enzimas Imobilizadas/química , Glucose Oxidase/química , Peroxidase do Rábano Silvestre/química , MicrofluídicaRESUMO
The methods of compartmentalized immobilization in multi-enzyme systems containing inorganic complexes and organic scaffolds (i.e. nucleic acid (RNA and DNA), protein and lipid) have been thoroughly investigated. Compartmentalization mostly focuses on dividing individual enzyme(s) into specific location or orientation of the enzymes cooperating in cascade reaction. Organic scaffolds are preferred because of their capability for simultaneous synthesis in biological systems. Besides, the most required methods of horseradish peroxidase (HRP) and glucose oxidase (GOD) enzymes including enzyme activity measurement, enzyme immobilization, removal, and re-hybridization, and enzyme attaching have been provided because they have been extensively applied in multi-enzyme systems. Organic scaffolds have a wide range and properties. Therefore, two methods including dockerin-cohesin linker and nucleotides interaction have been demonstrated for immobilization of enzyme on protein and DNA scaffold, respectively.
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Enzimas Imobilizadas , Glucose Oxidase , DNA , Enzimas Imobilizadas/metabolismo , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre/metabolismoRESUMO
Tryptophan (Trp), an α-amino acid, is the precursor of serotonin (5-hydroxytryptamine, 5-HT), which is involved in a variety of features of metabolic function and human nutrition. Evidence highlights the role of Trp metabolites (exclusively 5-HT) in the gastrointestinal (GI) tract; however, the mechanisms of action involved in the release of 5-HT in the GI tract are still unknown. Considering the fact that variations of 5-HT may facilitate the growth of certain GI disorders, gaining a better understanding of the function and release of 5-HT in the GI tract would be beneficial. Additionally, investigating Trp metabolism may clarify the relationship between Trp and gut microbiota. It is believed that other metabolites of Trp (mostly that of the kynurenine pathway) may play a significant role in controlling gut microbiota function. In this review, we have attempted to summarize the current research investigating the relationship of gut microbiota, Trp and 5-HT metabolism (with particular attention paid to their metabolite type, as well as a discussion of the research methods used in each study). Taking together, regarding the role that Trp/5-HT plays in a range of physical and mental diseases, the gut bacterial types, as well as the related disorders, have been exclusively considered.
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Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Humanos , Cinurenina/metabolismo , Serotonina/metabolismo , Triptofano/metabolismoRESUMO
Diabetic mellitus (DM) is the most communal metabolic disease resulting from a defect in insulin secretion, causing hyperglycemia by promoting the progressive destruction of pancreatic ß cells. This autoimmune disease causes many severe disorders leading to organ failure, lower extremity amputations, and ultimately death. Modern delivery systems e.g., nanofiber (NF)-based systems fabricated by natural and synthetic or both materials to deliver therapeutics agents and cells, could be the harbinger of a new era to obviate DM complications. Such delivery systems can effectively deliver macromolecules (insulin) and small molecules. Besides, NF scaffolds can provide an ideal microenvironment to cell therapy for pancreatic ß cell transplantation and pancreatic tissue engineering. Numerous studies indicated the potential usage of therapeutics/cells-incorporated NF mats to proliferate/regenerate/remodeling the structural and functional properties of diabetic skin ulcers. Thus, we intended to discuss the aforementioned features of the NF system for DM complications in detail.
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Diabetes Mellitus/terapia , Sistemas de Liberação de Medicamentos , Nanofibras , Engenharia Tecidual , Animais , Bandagens , Linhagem Celular Tumoral , Pé Diabético/terapia , Humanos , Células Secretoras de Insulina/metabolismo , Camundongos , RatosRESUMO
The effectiveness of silver nanomaterials (AgNMs), as antiviral agents, has been confirmed in humans against many different types of viruses. Nanobiocides-based AgNMs can be effectively applied to eliminate coronaviruses (CoVs), as the cause of various diseases in animals and humans, particularly the fatal human respiratory infections. Mostly, these NMs act effectively against CoVs, thanks to the NMs' fundamental anti-viral structures like reactive oxygen species (ROS), and photo-dynamic and photo-thermal abilities. Particularly, the antiviral activity of AgNMs is clarified under three inhibitory mechanisms including viral entry limitation, attachment inhibition, and viral replication limitation. It is believed that nanobiocide with other possible materials such as TiO2, silica and, carbon NMs exclusively nano-graphene materials can emerge as a more effective disinfectant for long-term stability with low toxicity than common disinfectants. Nanobiocides also can be applied for the prevention and treatment of viral infections specifically against COVID-19.
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The aim of this work is to co-load paclitaxel (PTX) and etoposide (ETP) in methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) nanoparticles (mPEG-PLGA NPs) to overcome pharmacokinetics and physiological limitations and enhance therapeutic efficacy for treating intracranial glioblastoma. Both drugs were loaded into mPEG-PLGA NPs by a nano-precipitation method. The resultant NPs demonstrated an enhanced cytotoxic effect indicated by lower IC50 values and augmented cell apoptosis to U87 and C6 glioma cell lines compared to both free drugs. Additionally, blood compatibility assays showed that the PTX/ETP co-loaded mPEG-PLGA NPs did not induce blood hemolysis, blood clotting, or platelet aggregation. In vivo anti-glioma efficacy evaluation in rats bearingintracranialC6glioma revealed a superior anti-glioma activity for the treatment with PTX/ETP co-loaded mPEG-PLGA NPs compared to other formulations, particularly a significantly longer median survival, 76 days compared to 36 days for free PTX and 37 days for free ETP treatment, respectively, and higher tumor regression, proved by magnetic resonance imaging (MRI).
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Glioblastoma , Nanopartículas , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/uso terapêutico , Etoposídeo , Glioblastoma/tratamento farmacológico , Paclitaxel/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ratos , Taxa de SobrevidaRESUMO
The disease 2019 (COVID-19) made a public health emergency in early 2020. Despite attempts for the development of therapeutic modalities, there is no effective treatment yet. Therefore, preventive measures in various settings could help reduce the burden of disease. In this chapter, the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing COVID-19, non-pharmaceutical approaches at individual and population level, chemoprevention, immunoprevention, preventive measures in different healthcare settings and other professions, special considerations in high-risk groups, and the role of organizations to hamper the psychosocial effects will be discussed.
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COVID-19 , Vacinas Anticâncer , Atenção à Saúde , Humanos , Imunoterapia , SARS-CoV-2RESUMO
Serotonin (5-HT) levels have been associated with several exclusively metabolic disorders. Herein, a new approach for 5-HT level as a novel biomarker of diabetes mellitus is considered using a simple nanocomposite and HPLC method. Reduced graphene oxide (rGO) comprising gold nanoparticles (AuNPs) was decorated with 18-crown-6 (18.Cr.6) to fabricate a simple nanocomposite (rGO-AuNPs-18.Cr.6). The nanocomposite was positioned on a glassy carbon electrode (GCE) to form an electrochemical sensor for the biomarker 5-HT in the presence of L-tryptophan (L-Trp), dopamine (DA), ascorbic acid (AA), urea, and glucose. The nanocomposite exhibited efficient catalytic activity for 5-HT detection by square-wave voltammetry (SWV). The proposed sensor displayed high selectivity, excellent reproducibility, notable anti-interference ability, and long-term stability even after 2 months. SWV defined a linear range of 5-HT concentration from 0.4 to 10 µg L-1. A diabetic animal model (diabetic zebrafish model) was then applied to investigate 5-HT as a novel biomarker of diabetes. A limit of detection (LOD) of about 0.33 µg L-1 was found for the diabetic group and 0.15 µg L-1 for the control group. The average levels of 5-HT obtained were 9 and 2 µg L-1 for control and diabetic groups, respectively. The recovery, relative standard deviation (RSD), and relative error (RE) were found to be about 97%, less than 2%, and around 3%, respectively. The significant reduction in 5-HT level in the diabetic group compared to the control group proved that the biomarker 5-HT can be applied for the early diagnosis of diabetes mellitus.
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Diabetes Mellitus/diagnóstico , Técnicas Eletroquímicas/métodos , Serotonina/análise , Animais , Ácido Ascórbico/análise , Biomarcadores/metabolismo , Dopamina/análise , Eletrodos , Glucose/análise , Ouro/química , Ligação de Hidrogênio , Limite de Detecção , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/química , Tamanho da Partícula , Reprodutibilidade dos Testes , Triptofano/análise , Ureia/análise , Peixe-ZebraRESUMO
Herein, we fabricated the antibacterial nanofibrous mats composed of cellulose acetate (CA) nanofibers loaded with erythromycin-chitosan nanoparticles (Ery-CS NPs) intended for infected wound dressing. The Ery-loaded CS NPs were prepared by ionic gelation process and then incorporated into the CA electrospun nanofibers (NFs). Regarding physiochemical properties, the NPs and obtained mats were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), attenuated total reflection fourier transform infrared (ATR-FTIR), and contact angle measurement. The antimicrobial activity and cell viability of fibroblast cells were also evaluated. The results indicated that Ery was loaded into CS NPs with high encapsulation efficiency (95%). The CA NFs (17% w/v) incorporated with the Ery-CS NPs (12 wt%) displayed smooth homogenous morphology with 141.7 ± 91.7 nm average diameter. The relevant analyses confirmed that the NPs incorporated into NFs and provided high water holding capacity with high porosity. Finally, Ery-CS NPs/CA mats were able to inhibit the growth of both Gram-positive and Gram-negative bacteria as well as showed no cytotoxic effect on the human dermal fibroblast cells. Overall, our findings concluded that the proposed system could be potentially applied as the proper antibacterial mats for infected wound dressing applications.
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Antibacterianos/farmacologia , Celulose/análogos & derivados , Quitosana/química , Eritromicina/farmacologia , Infecção dos Ferimentos/tratamento farmacológico , Animais , Antibacterianos/química , Bandagens , Linhagem Celular , Sobrevivência Celular , Celulose/química , Eritromicina/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Nanofibras , PorosidadeRESUMO
Despite the recent advances in the treatment strategies of peripheral nerve system defects, peripheral nerve injury (PNI) is still one of the most important health issues with increasing incidence worldwide. The most commonly used treatment approaches are allografts, xenografts, and autologous, which have some drawbacks, including complications, limited source of the donor tissue, tubular collapse, and scar tissue formation. In this context, regenerative medicine has been introduced as a powerful approach to improve the healing process and obtain acceptable functional recovery in the injury site using living cells, scaffold, and bioactive (macro-) molecules. Amongst them, scaffold as a three-dimensional (3D) support biomaterial, structurally bridged the gap or site of injury in order to provide physical and chemical cues to promote correct reinnervation and functional regeneration. Amongst different scaffolding biomaterials, naturally occurring biological macromolecules (more especially proteins and polysaccharides)-based hydrogels exhibited promising results due to their fascinating physicochemical, as well as physiologically relevant properties. This review highlights the recent progress in the development of natural hydrogels-based neural scaffolds. Furthermore, PNI healing process, current status, and challenges are also shortly discussed.
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Materiais Biocompatíveis/uso terapêutico , Hidrogéis/uso terapêutico , Peptídeos/uso terapêutico , Traumatismos dos Nervos Periféricos/terapia , Polissacarídeos/uso terapêutico , Engenharia Tecidual , Animais , Humanos , Regeneração Nervosa , Alicerces TeciduaisRESUMO
Serotonin (5-hydroxytryptamine, 5-HT) is an important neurotransmitter which plays a significant role in various functions in the body, such as appetite, emotions, and autonomic functions. It is well known that biomarker 5-HT levels can be correlated to several diseases and disorders such as depression, anxiety, irritable bowel, and sleep trouble. Among various methods for detecting the 5-HT biomarker, electrochemical techniques have attracted great interest due to their low cost and ease of operation. However, sensitive and precise electrochemical detection of 5-HT levels is not possible using bare electrodes, thus requiring electrode modification. The present review aims to describe the different electroanalytical methods for 5-HT detection using various surface-modified electrodes such as glassy carbon, carbon fiber, diamond, graphite, and metal electrodes modified with conductive polymers. Perspectives and the modification of electrode surface using applied polymers for 5-HT detection have also been presented.