RESUMO
Este trabalho, partindo do tema elaborado, levantou o seguinte problema: As propriedades e vantagens estudadas nas membranas de Hidrogel, se faz desse material eficaz no tratamento dos tecidos periodontais na doença periodontal. Sendo assim, o objetivo deste trabalho foi realizar um levantamento bibliográfico sobre as propriedades e vantagens do uso de membranas de Hidrogel na Regeneração Óssea Guiada nos casos da perda óssea e a recessão gengival associada à Doença Periodontal. O uso de membrana para Regeneração Óssea Guiada (ROG) é um componente essencial do tratamento de doenças periodontais e na regeneração óssea. Neste caso, discutiremos as propriedades dos hidrogéis e seus benefícios e limitações nessa área. Apesar dos desafios significativos existentes, a regeneração óssea baseada em hidrogel é uma grande promessa para o futuro tratamento de doenças e defeitos relacionados aos ossos. Com uma compreensão aprofundada os hidrogéis serão, sem dúvida, uma ferramenta poderosa para o tratamento clínico de defeitos ósseos no futuro.
This study, based on the topic elaborated, raised the following problem: The properties and advantages studied in Hydrogel membranes and if this material can be effective in the treatment of periodontal tissues in periodontal disease. The objective of this work was to perform a bibliographic survey on the properties and advantages of using Hydrogel membranes in Guided Bone Regeneration in cases of bone loss and gingival recession associated with Periodontal Disease. The use of Guided Bone Regeneration (GBR) membrane is an essential component of the treatment of periodontal diseases and bone regeneration. In this case, we discussed the properties of hydrogels and their benefits and limitations in this area. Despite significant challenges, the hydrogel-based bone regeneration holds great promise for the future treatment of bone-related diseases and defects. With in-depth understanding, hydrogels will undoubtedly be a powerful tool for clinical treatment of bone defects in the future.
Assuntos
Doenças Periodontais , Regeneração Óssea , Hidrogéis , MembranasRESUMO
Hydrogels based on natural polymers have aroused interest from the scientific community. The aim of this investigation was to obtain natural extracts from mango peels and to evaluate their addition (1, 3, and 5%) on the rheological behavior of mango starch hydrogels. The total phenolic content, antioxidant activities, and phenolic acid profile of the natural extracts were evaluated. The viscoelastic and thixotropic behavior of hydrogels with the addition of natural extracts was evaluated. The total phenol content and antioxidant activity of the extracts increased significantly (p<0.05) with the variation of the ethanol-water ratio; the phenolic acid profile showed the contain of p-coumaric, ellagic, ferulic, chlorogenic acids, epicatechein, catechin, querecetin, and mangiferin. The viscoelastic behavior of the hydrogels showed that the storage modulus G' is larger than the loss modulus G'' indicating a viscoelastic solid behavior. The addition of extract improved the thermal stability of the hydrogels. 1% of the extracts increase viscoelastic and thixotropic properties, while concentrations of 3 to 5% decreased. The recovery percentage (%Re) decreases at concentrations from 0% to 1% of natural extracts, however, at concentrations from 3% to 5% increased.
Assuntos
Antioxidantes , Hidrogéis , Mangifera , Extratos Vegetais , Reologia , Amido , Mangifera/química , Hidrogéis/química , Extratos Vegetais/química , Amido/química , Antioxidantes/química , Viscosidade , Frutas/química , Fenóis/químicaRESUMO
BACKGROUND: Various types of hydrogel compounds have recently been developed for controlling invasive and pest ants in a range of environmental settings including agricultural, urban and natural areas. The current study evaluated the potential of sodium polyacrylate (ACR) hydrogels to effectively deliver liquid baits to Argentine ants. RESULTS: Relative to standard polyacrylamide (PAM) hydrogels, individual ACR hydrogel particles were approximately five-fold heavier; this may affect how ants interact with the bait particles, and further influence bait uptake and efficacy. Additionally, ACR hydrogels had significantly higher water absorption capacity and significantly slower rate of water loss, especially during the first 2 h. The efficacy of ACR hydrogel bait containing 0.005% fipronil and various attractants was evaluated on laboratory colonies. Results demonstrated that ACR hydrogel acceptance is significantly increased by the addition of feeding attractants. In addition, a field trial was performed in a nature reserve invaded by Argentine ants to evaluate the efficacy of ACR hydrogel bait. The field trial demonstrated that ACR hydrogel bait containing 0.005% fipronil with various attractants is highly effective and that ant densities throughout the baited plots declined by >99% within 7 days. CONCLUSIONS: The results of this study demonstrate that: (i) fipronil is highly effective for Argentine ant control in natural areas when used in low concentrations (0.005%); (ii) ACR hydrogels are an effective tool for delivering liquid baits to Argentine ants; and (iii) hydrogel baits augmented with various attractants including salt, protein and pheromone are highly attractive to Argentine ants. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Assuntos
Resinas Acrílicas , Formigas , Hidrogéis , Controle de Insetos , Inseticidas , Pirazóis , Animais , Formigas/efeitos dos fármacos , Inseticidas/farmacologia , Controle de Insetos/métodos , Pirazóis/farmacologia , Conservação dos Recursos NaturaisRESUMO
Natural fibers are being employed in the development of the next generation of biomaterials, due to their reduced environmental impact and the ease of their functionalization with natural polymers. In this study, Barba del Viejo fibers were treated with NaOH and bonded with alginate through ionic gelation by using CaCâ2, which facilitates ionic interactions between alginate and Ca2+ions. Additionally, antimicrobial Barba del Viejo/alginate/silver nanoparticles(BVA/Ago) scaffolds were developed from the NaOH-treated BV-microfibers, silver salt and sodium alginate, with mint leaves extract as a nucleating agent. The functional and crystalline structure of microfibers and the hydrogels developed were analyzed using the FTIR and XRD. SEM explained that the diameter of the NaOH-treated microfibers was â1.32 µm. The morphological images of the hydrogels, confirm the functionalization of alginate with microfibers and the formation of Ago nanoparticles within the hydrogels network. The swelling ratio of the hydrogels increased with alginate functionalization on BV-microfibers, improving NaOH treatment, but decreased the degradation rate. UV-spectra showed absorption peaks in the wavelength range of between 432 and 442 nm, confirming the surface plasmon resonance effect of the Ago nanoparticles within the scaffolds. TEM analysis confirms that the Ago nanoparticles in hydrogels were spherical in shape, with sizes ranging from â2 and 10 nm. The zeta potential analysis indicates that the Ago nanoparticles possess negative charges, providing a stable surface that helps to prevent aggregation and, therefore, demonstrating a homogeneous distribution throughout all the BVA/Ago scaffolds prepared. The antimicrobial studies reveal that the BVA/Ago scaffolds exhibit significant antibacterial activity against E.coli and S.aureus bacteria. Further investigations are affirmed to study the potential applications of these scaffolds in infection-control wound dressing.
Assuntos
Alginatos , Química Verde , Hidrogéis , Nanopartículas Metálicas , Prata , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/síntese química , Alginatos/química , Prata/química , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Testes de Sensibilidade MicrobianaRESUMO
Natural polymers have recently been investigated for various applications, such as 3D printing and healthcare, including treating infections. Among microbial infections, fungal diseases remain overlooked, with limited therapeutic options and high recurrence. Cutaneous cryptococcosis is an opportunistic fungal infection triggered by mechanical inoculation or hematogenous dissemination of the yeast that causes cryptococcal pneumonia and meningitis. Every year, Cryptococcus neoformans endanger the lives of immunosuppressed hosts, resulting in 180,000 deaths per year. Nonetheless, healthy individuals can also be affected by this fungal infection. Cryptococcosis has a restricted and expensive therapeutic regimen with no topical approach to skin manifestations. This study sought to create a 3D printable biodegradable polymeric hydrogel carrying ketoconazole, a low-cost antifungal drug with reported anticryptococcal activity. The developed hydrogel exhibited good 3D printability and rheological properties, including a pseudoplastic behavior. The FTIR spectra of cross-linked hydrogels revealed interactions between alginate and Ca+2, referred to as the egg-box model, indicated by the decrease in peaks at 1600 and 1410 cm-1. Furthermore, the hydrogel loaded with ketoconazole showed remarkable antifungal activity against C. neoformans strains indicated by inhibition zones, which cross-linking did not seem to affect its antifungal performance. The developed material remained structurally stable for up to 12 days (288 h) in swelling studies, and preliminary cytotoxicity performed with V79 cells indicates potential for in vivo studies and topical application.
Assuntos
Alginatos , Antifúngicos , Quitosana , Cryptococcus neoformans , Hidrogéis , Cetoconazol , Impressão Tridimensional , Cetoconazol/química , Cetoconazol/farmacologia , Cetoconazol/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/administração & dosagem , Hidrogéis/química , Hidrogéis/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Alginatos/química , Quitosana/química , Testes de Sensibilidade Microbiana , Humanos , AnimaisRESUMO
PURPOSE: To assess the cytotoxicity and wound healing properties of an alginate hydrogel containing calendula glycolic extract. METHODS: Cell viability in murine fibroblasts (3T3 cells) was evaluated using MTT and SRB assays. The wound healing effect was tested in an incisional wound model on 50 female Wistar rats, divided into two groups: rats treated with alginate hydrogel (n = 25), and rats treated with calendula-alginate hydrogel. Wound healing was assessed by measuring wound retraction rate and histological analysis of lesion tissues over a 28-day period. Histological analyses were performed on days 2, 7, 14, 21, and 28 post-surgery to examine inflammatory infiltrate, macrophage count, and angiogenesis. Picrosirius red staining was used to compare the relative abundance of collagen types I and III fibers. RESULTS: Cytotoxicity tests on 3T3 cells revealed increased cell viability with the calendula-alginate hydrogel. The calendula-alginate hydrogel also demonstrated a significant improvement in wound closure, supported by histopathological analysis, showing reduced inflammation, increased macrophage activity, and enhanced collagen deposition. CONCLUSIONS: These findings evidenced the therapeutic potential of combining calendula extract and alginate for promoting enhanced wound healing.
Assuntos
Alginatos , Calendula , Sobrevivência Celular , Hidrogéis , Extratos Vegetais , Ratos Wistar , Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Alginatos/farmacologia , Feminino , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Camundongos , Hidrogéis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Calendula/química , Ratos , Fibroblastos/efeitos dos fármacos , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/uso terapêutico , Células 3T3 , Reprodutibilidade dos Testes , Fatores de Tempo , Glicolatos/farmacologia , Colágeno/efeitos dos fármacos , Modelos Animais de DoençasRESUMO
3D skin models have been explored as an alternative method to the use of animals in research and development. Usually, human skin equivalents comprise only epidermis or epidermis/dermis layers. Herein, we leverage 3D bioprinting technology to fabricate a full-thickness human skin equivalent with hypodermis (HSEH). The collagen hydrogel-based structure provides a mimetic environment for skin cells to adhere, proliferate and differentiate. The effective incorporation of the hypodermis layer is evidenced by scanning electron microscopy, immunofluorescence, and hematoxylin and eosin staining. The transcriptome results underscore the pivotal role of the hypodermis in orchestrating the genetic expression of a multitude of genes vital for skin functionality, including hydration, development and differentiation. Accordingly, we evidence the paramount significance of full-thickness human skin equivalents with hypodermis layer to provide an accurate in vitro platform for disease modeling and toxicology studies.
Assuntos
Bioimpressão , Impressão Tridimensional , Pele , Humanos , Bioimpressão/métodos , Pele/metabolismo , Engenharia Tecidual/métodos , Hidrogéis , Alicerces Teciduais , Queratinócitos/metabolismo , Regulação da Expressão Gênica , Pele Artificial , Diferenciação CelularRESUMO
Nitric oxide (NO) holds promise for wound healing due to its antimicrobial properties and role in promoting vasodilation and tissue regeneration. The local delivery of NO to target cells or organs offers significant potential in numerous biomedical applications, especially when NO donors are integrated into nontoxic viscous matrices. This study presents the development of robust cellulose nanofibril (CNF) hydrogels designed to control the release of nitric oxide (NO) generated in situ from a NO-donor molecule (S-nitrosoglutathione, GSNO) obtained from the nitrosation of its precursor molecule glutathione (GSH). CNF, efficiently isolated from sugar cane bagasse, exhibited a high aspect ratio and excellent colloidal stability in water. Although depletion forces could be observed upon the addition of GSH, this effect did not significantly alter the morphology of the CNF network at low GSH concentrations (<20 mM). Ionic cross-linking with Ca2+ resulted in nontoxic and robust hydrogels (elastic moduli ranging from 300 to 3000 Pa) at low CNF solid content. The release rate of NO from GSNO decreased in CNF from 1.61 to 0.40 mmol. L-1·h-1 when the nanofibril content raised from 0.3 to 1.0 wt %. The stabilization effect monitored for 16 h was assigned to hydrogel mesh size, which was easily tailored by modifying the concentration of CNF in the initial suspension. These results highlight the potential of CNF-based hydrogels in biomedical applications requiring a precise NO delivery.
Assuntos
Materiais Biocompatíveis , Cálcio , Celulose , Hidrogéis , Teste de Materiais , Nanofibras , Óxido Nítrico , Hidrogéis/química , Hidrogéis/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico/química , Celulose/química , Nanofibras/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cálcio/química , Cálcio/metabolismo , Tamanho da Partícula , Reagentes de Ligações Cruzadas/químicaRESUMO
Purpose: Tissue engineering aims to recreate natural cellular environments to facilitate tissue regeneration. Gelatin methacrylate (GelMA) is widely utilized for its biocompatibility, ability to support cell adhesion and proliferation, and adjustable mechanical characteristics. This study developed a GelMA and graphene bioink platform at concentrations of 1, 1.5, and 2 mg/mL to enhance scaffold properties for tissue engineering applications. Patients and Methods: Graphene was incorporated into GelMA matrices to improve mechanical strength and electrical conductivity of the bioinks. The compressive strength and thermal stability of the resulting GelMA/graphene scaffolds were assessed through DSC analysis and mechanical testing. Cytotoxicity assays were conducted to determine cell survival rates. Cryoprinting at -30°C was employed to preserve scaffold structure and function. The chorioallantoic membrane (CAM) assay was used to evaluate biocompatibility and angiogenic potential. Results: The integration of graphene significantly amplified the compressive strength and thermal stability of GelMA scaffolds. Cytotoxicity assays indicated robust cell survival rates of 90%, confirming the biocompatibility of the developed materials. Cryoprinting effectively preserved scaffold integrity and functionality. The CAM assay validated the biocompatibility and angiogenic potential, demonstrating substantial vascularization upon scaffold implantation onto chick embryo CAM. Conclusion: Integrating graphene into GelMA hydrogels, coupled with low-temperature 3D printing, represents a potent strategy for enhancing scaffold fabrication. The resultant GelMA/graphene scaffolds exhibit superior mechanical properties, biocompatibility, and pro-vascularization capabilities, making them highly suitable for diverse tissue engineering and regenerative medicine applications.
Assuntos
Materiais Biocompatíveis , Sobrevivência Celular , Força Compressiva , Gelatina , Grafite , Hidrogéis , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Grafite/química , Alicerces Teciduais/química , Gelatina/química , Animais , Embrião de Galinha , Sobrevivência Celular/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Metacrilatos/química , Membrana Corioalantoide/efeitos dos fármacos , Humanos , Teste de Materiais , TintaRESUMO
In the present work, the osteogenic and angiogenic properties of, previously developed, semi-interpenetrated HEMA-EGDMA polymeric networks (sIPN) with and without alginate with application in bone tissue engineering (BTE) were studied. In vitro characterization studies were performed using rat bone marrow progenitor cells (BMPCs), EA.hy926 endothelial cells, and rat vascular smooth muscle cells (VSMCs). Based on the in vitro results of both this work and previous ones, the hydrogels were selected to carry out in vivo studies to find out their capacity as a biomaterial using a bone regeneration model. Our results indicate that the incorporation of alginate into the HEMA-EGDMA polymeric network promotes osteogenic and angiogenic capacity in cell cultures of BMPCs and both EA.hy926 and VSMCs, respectively, and also increases bone formation and vascular structures in in vivo studies, demonstrating its potential use as a biomaterial in BTE.
Assuntos
Alginatos , Materiais Biocompatíveis , Regeneração Óssea , Hidrogéis , Animais , Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Regeneração Óssea/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Osteogênese/efeitos dos fármacos , Engenharia Tecidual , Humanos , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Teste de Materiais , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Células-Tronco/metabolismo , Células-Tronco/citologia , Células Cultivadas , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/citologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Miócitos de Músculo Liso/metabolismo , Células Endoteliais/metabolismoRESUMO
PURPOSE: To describe the effects of melatonin associated with bacterial cellulose-based hydrogel on healing of skin wounds in diabetic rats. METHODS: Streptozotocin was used to induce diabetes in Wistar rats. After wound induction, animals were randomly divided into groups GC, GDCC, GDCB, and GDMCB. Animals were evaluated in days 3, 7, and 14 for the following variables: glycemic levels, histopathological and histochemical analyses, healing rate, morphometry and C-reactive protein. RESULTS: There was no change in glycemic levels in the diabetic animals as a result of the treatments; histopathological analyses showed better healing in GDCB and GDMCB groups, as well as histochemistry; at day 14, the highest healing rate was observed in animals from the GDMCB group, reaching almost 100%; morphometry revealed a significant increase of fibroblasts and reduction of macrophages and blood vessels in lesions treated with bacterial cellulose associated or not with melatonin when compared to the other experimental groups. There was also an increase in C-reactive protein in GDCC group at day 14. CONCLUSION: Bacterial cellulose-based dressings associated with systemic melatonin showed beneficial results in experimentally induced wounds in diabetic rats, favoring the healing process.
Assuntos
Celulose , Diabetes Mellitus Experimental , Melatonina , Ratos Wistar , Pele , Cicatrização , Animais , Melatonina/uso terapêutico , Melatonina/farmacologia , Cicatrização/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Celulose/uso terapêutico , Celulose/farmacologia , Masculino , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia , Hidrogéis/uso terapêutico , Distribuição Aleatória , Ratos , Proteína C-Reativa/análise , Fatores de Tempo , Reprodutibilidade dos Testes , Glicemia/análise , Glicemia/efeitos dos fármacos , Antioxidantes/uso terapêutico , Antioxidantes/farmacologiaRESUMO
Herein, four different grafted chitosans were synthesized by covalent attachment of glycine, L-arginine, L-glutamic acid, or L-cysteine to the chitosan chains. All products were subsequently permethylated to obtain their corresponding quaternary ammonium salts to enhance the inherent antimicrobial properties of native chitosan. In all cases, transparent hydrogels with the following remarkable characteristics were obtained: i) high-water absorption capacity (32-44 g H2O per g of polymer), ii) viscoelastic behavior at low deformations, iii) flexibility when subjected to deformations and iv) stability over long time scales. All the permethylated derivatives successfully inhibited 100 % of the growth of S. aureus. They also exhibited higher antimicrobial activity against E. coli than native chitosan. The structure of the chemically crosslinked products was more stable under external perturbations than that of the physically crosslinked ones. Between the chemically crosslinked products, the permethylated glutamic acid-grafted chitosan exhibited a noteworthy higher water absorption capacity with respect to that modified with cysteine, which makes it the most promising material for various industrial applications, including biomedical and food industries. Regarding biomedical applications, this derivative met the required physicochemical criteria for wound dressings, which encourages the pursuit of biological studies necessary to ensure the safety of its use for this application.
Assuntos
Bandagens , Quitosana , Hidrogéis , Quitosana/química , Quitosana/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/síntese química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Água/química , Cicatrização/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologiaRESUMO
Osteomyelitis is an inflammation of bone tissue usually caused by pyogenic bacteria. The most recurrent clinical approach consists of bone debridement followed by parenteral administration of antibiotics. However, systemic antibiotic treatment has limitations regarding absorption rate and bioavailability over time. The main challenge of osteomyelitis treatment consists of coupling the persistent infection treatment with the regeneration of the bone debrided. In this work, we developed an injectable drug delivery system based on poloxamer 407 hydrogel containing undoped Mg, Zn-doped tricalcium phosphate (ß-TCP), and teicoplanin, a broad-spectrum antibiotic. We evaluated how the addition of teicoplanin and ß-TCP affected the micellization, gelation, particle size, and surface charge of the hydrogel. Later, we studied the hydrogel degradation and drug delivery kinetics. Finally, the bactericidal, biocompatibility, and osteogenic properties were evaluated through in vitro studies and confirmed by in vivo Wistar rat models. Teicoplanin was found to be encapsulated in the corona portions of the hydrogel micelles, yielding a bigger hydrodynamics radius. The encapsulated teicoplanin showed a sustained release over the evaluated period, enough to trigger antibacterial properties against Gram-positive bacteria. Besides, the formulations were biocompatible and showed bone healing ability and osteogenic properties. Finally, in vivo studies confirmed that the proposed locally injected formulations yielded osteomyelitis treatment with superior outcomes than parenteral administration while promoting bone regeneration. In conclusion, the presented formulations are promising drug delivery systems for osteomyelitis treatment and deserve further technological improvements.
Assuntos
Antibacterianos , Fosfatos de Cálcio , Hidrogéis , Osteogênese , Osteomielite , Ratos Wistar , Teicoplanina , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Animais , Fosfatos de Cálcio/química , Teicoplanina/administração & dosagem , Teicoplanina/farmacologia , Teicoplanina/química , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Ratos , Hidrogéis/química , Hidrogéis/administração & dosagem , Osteogênese/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Humanos , Staphylococcus aureus/efeitos dos fármacos , Poloxâmero/químicaRESUMO
Actinic cheilitis (AC) is a lip disorder, with no standard treatment. Imiquimod (IMIQ) is an immunomodulator that treat precancerous lesions; however, its commercial form causes severe adverse effects. This study aimed to assess IMQ release from a chitosan hydrogel containing 0.05 % nanoencapsulated (NANO) imiquimod (IMIQ-0.05 %-NANO) and its efficacy in AC treatment. The hydrogels were prepared by incorporating chitosan into polymeric nanocapsules (NCimiq) loaded with IMQ, produced using the interfacial deposition of preformed polymer method. IMQ release was evaluated using automated Franz Cells. A triple-blind randomized controlled trial (49 subjects) compared the efficacy of: IMIQ-0.05 %-NANO, 5 % free imiquimod (IMIQ-5 %), 0.05 % free imiquimod (IMIQ-0.05 %), and placebo hydrogel. The IMIQ-NANO-0.05 % and IMIQ-5 % groups exhibited significantly higher rates of clinical improvement (p < 0.05); however, the IMIQ-5 % group experienced more adverse effects (92.3 % of subjects) compared to other groups (p < 0.05). In conclusion, in the studied sample, IMIQ-NANO-0.05 % was a safe and effective option to treat AC.
Assuntos
Queilite , Hidrogéis , Imiquimode , Humanos , Imiquimode/administração & dosagem , Queilite/tratamento farmacológico , Queilite/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Hidrogéis/química , Nanocápsulas/química , Quitosana/química , Liberação Controlada de Fármacos , Adulto , Resultado do Tratamento , IdosoRESUMO
Producing food in quantity and quality to meet the growing population demand is a challenge for the coming years. In addition to the need to improve the use and efficiency of conventional agricultural inputs, we face climate change and disparity in access to food. In this context, creating innovative, efficient, and ecologically approaches is necessary to transform this global scenario. Several delivery systems are being developed to encapsulate agrochemicals, aiming to improve the controlled release of active ingredients and protect them against environmental biotic and abiotic factors. Among these systems, hydrogel spheres are particularly notable for their ability to be fabricated from biodegradable materials, allowing the encapsulation of molecules, nanomaterials, and even organisms (e.g., bacteria and fungi). This review provides an overview of the latest progress in developing polysaccharide-based hydrogel spheres for agriculture. In addition, we describe methods for preparing hydrogel spheres and discuss the encapsulation and release of agricultural inputs in the field. Finally, we put hydrogel spheres into perspective and seek to highlight some current challenges in the field to spark new inspiration and improve the development of environmentally friendly and cost-effective delivery systems for the agricultural sector.
Assuntos
Agricultura , Preparações de Ação Retardada , Hidrogéis , Polissacarídeos , Hidrogéis/química , Agricultura/métodos , Polissacarídeos/química , Agroquímicos/químicaRESUMO
Large bone defects are a significant health problem today with various origins, including extensive trauma, tumours, or congenital musculoskeletal disorders. Tissue engineering, and in particular bone tissue engineering, aims to respond to this demand. As such, we propose a specific model based on Elastin-Like Recombinamers-based click-chemistry hydrogels given their high biocompatibility and their potent on bone regeneration effect conferred by different bioactive sequences. In this work we demonstrate, using biochemistry, histology, histomorphometry and imaging techniques, the biocompatibility of our matrix and its potent effect on bone regeneration in a model of bone parietal lesion in female New Zealand rabbits.
Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Elastina , Hidrogéis , Engenharia Tecidual , Animais , Feminino , Coelhos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Química Click/métodos , Elastina/química , Hidrogéis/química , Hidrogéis/farmacologia , Engenharia Tecidual/métodos , Alicerces Teciduais/químicaRESUMO
PURPOSE: Bacterial cellulose (BC) has shown high capacity for the treatment of wounds and burns, providing a moisty environment. Calcium alginate can be associated with BC to create gels that aid in wound debridement and contribute to appropriate wound healing. This study is aimed at characterizing and evaluating the use of bacterial cellulose/alginate gel in skin burns in rats. METHODS: Cellulose and cellulose/alginate gels were compared regarding the capacity of liquid absorption, moisture, viscosity, and potential cytotoxicity. The 2nd degree burns were produced using an aluminum metal plate (2.0cm) at 120ºC for 20s on the back of rats. The animals were divided into non-treated, CMC(Carboxymethylcellulose), Cellulose(CMC with bacterial cellulose), and Cellulose/alginate(CMC with bacterial cellulose and alginate). The animals received topical treatment 3 times/week. Biochemical (MPO, NAG and oxidative stress), histomorphometry and immunohistochemical assays (IL-1ß IL-10 and VEGF) were conducted on the 14th, 21st, 28th, and 35th days. RESULTS: Cellulose/Alginate gel showed higher absorption capacity and viscosity compared to Cellulose gel, with no cytotoxic effects. Cellulose/alginate presented lower MPO values, a higher percentage of IL-10, with greater and balanced oxidative stress profile. CONCLUSIONS: The use of cellulose/alginate gel reduced neutrophils and macrophage activation and showed greater anti-inflammatory response, which can contribute to healing chronic wounds and burns.
Assuntos
Alginatos , Queimaduras , Celulose , Hidrogéis , Ratos Wistar , Cicatrização , Animais , Alginatos/uso terapêutico , Celulose/uso terapêutico , Queimaduras/tratamento farmacológico , Queimaduras/terapia , Cicatrização/efeitos dos fármacos , Hidrogéis/uso terapêutico , Masculino , Ratos , Ácido Glucurônico/uso terapêutico , Ácidos Hexurônicos/uso terapêutico , Reprodutibilidade dos Testes , Viscosidade , Estresse Oxidativo/efeitos dos fármacos , Imuno-Histoquímica , Fatores de Tempo , Pele/lesões , Pele/efeitos dos fármacosRESUMO
PURPOSE: To evaluate using a biocellulose-based hydrogel as an adjuvant in the healing process of arterial ulcers. METHODS: A prospective single group quasi-experimental study was carried out with chronic lower limb arterial ulcer patients. These patients received biocellulose-based hydrogel dressings and outpatient guidance on dressing and periodic reassessments. The primary outcomes were the ulcer-healing rate and product safety, which were assessed by ulcer area measured in photographic records of pre-treatment and posttreatment after 7, 30, and 60 days. Secondary outcomes were related to clinical assessment by the quality-of-life scores (SF-36 and EQ-5D) and pain, evaluated by the visual analogue scale (VAS). RESULTS: Seventeen participants were included, and one of them was excluded. Six patients (37%) had complete wound healing, and all patients had a significant reduction in the ulcer area during follow-up (233.6mm2 versus 2.7mm2) and reduction on the score PUSH 3.0 (p < 0.0001). The analysis of the SF-36 and EQ-5D questionnaires showed a statistically significant improvement in almost all parameters analyzed and with a reduction of pain assessed by the VAS. CONCLUSIONS: The biocellulose-based hydrogel was safe and showed a good perspective to promoting the necessary conditions to facilitate partial or complete healing of chronic arterial ulcers within a 60-day follow-up. Quality of life and pain were positively affected by the treatment.
Assuntos
Qualidade de Vida , Cicatrização , Humanos , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Doença Crônica , Celulose/uso terapêutico , Celulose/administração & dosagem , Úlcera da Perna/terapia , Bandagens , Idoso de 80 Anos ou mais , Medição da Dor , Hidrogéis/uso terapêuticoRESUMO
Envisaging to improve the evaluation of ophthalmic drug products while minimizing the need for animal testing, our group developed the OphthalMimic device, a 3D-printed device that incorporates an artificial lacrimal flow, a cul-de-sac area, a moving eyelid, and a surface that interacts effectively with ophthalmic formulations, thereby providing a close representation of human ocular conditions. An important application of such a device would be its use as a platform for dissolution/release tests that closely mimic in vivo conditions. However, the surface that artificially simulates the cornea should have a higher resistance (10 min) than the previously described polymeric films (5 min). For this key assay upgrade, we describe the process of obtaining and thoroughly characterizing a hydrogel-based hybrid membrane to be used as a platform base to simulate the cornea artificially. Also, the OphthalMimic device suffered design improvements to fit the new membrane and incorporate the moving eyelid. The results confirmed the successful synthesis of the hydrogel components. The membrane's water content (86.25 ± 0.35 %) closely mirrored the human cornea (72 to 85 %). Furthermore, morphological analysis supported the membrane's comparability to the natural cornea. Finally, the performance of different formulations was analysed, demonstrating that the device could differentiate their drainage profile through the viscosity of PLX 14 (79 ± 5 %), PLX 16 (72 ± 4 %), and PLX 20 (57 ± 14 %), and mucoadhesion of PLXCS0.5 (69 ± 1 %), PLX16CS1.0 (65 ± 3 %), PLX16CS1.25 (67 ± 3 %), and the solution (97 ± 8 %). In conclusion, using the hydrogel-based hybrid membrane in the OphthalMimic device represents a significant advancement in the field of ophthalmic drug evaluation, providing a valuable platform for dissolution/release tests. Such a platform aligns with the ethical mandate to reduce animal testing and promises to accelerate the development of safer and more effective ophthalmic drugs.
Assuntos
Hidrogéis , Humanos , Hidrogéis/química , Soluções Oftálmicas/química , Impressão Tridimensional , Córnea/efeitos dos fármacos , Córnea/metabolismo , Administração Oftálmica , Membranas ArtificiaisRESUMO
Scaffolds for the filling and regeneration of osteochondral defects are a current challenge in the biomaterials field, and solutions with greater functionality are still being sought. The novel approach of this work was to obtain scaffolds with biologically active additives possessing microstructural, permeability, and mechanical properties, mimicking the complexity of natural cartilage. Four types of scaffolds with a gelatin/alginate matrix modified with hydroxyapatite were obtained, and the relationship between the modifiers and substrate properties was evaluated. They differed in the type of second modifier used, which was hydrated MgCl2 in two proportions, ZnO, and nanohydroxyapatite. The samples were obtained by freeze-drying by using two-stage freezing. Based on microstructural observations combined with X-ray microanalysis, the microstructure of the samples and the elemental content were assessed. Permeability and mechanical tests were also performed. The scaffolds exhibited a network of interconnected pores and complex microarchitecture, with lower porosity at the surface (15 ± 7 to 29 ± 6%) and higher porosity at the center (67 ± 8 to 75 ± 8%). The additives had varying effects on the pore sizes and permeabilities of the samples. ZnO yielded the most permeable scaffolds (5.92 × 10-11 m2), whereas nanohydroxyapatite yielded the scaffold with the lowest permeability (1.18 × 10-11 m2), values within the range reported for trabecular bone. The magnesium content had no statistically significant effect on the permeability. The best mechanical parameters were obtained for ZnO samples and those containing hydrated MgCl2. The scaffold's properties meet the criteria for filling osteochondral defects. The developed scaffolds follow a biomimetic approach in terms of hierarchical microarchitecture and mechanical parameters as well as chemical composition. The obtained composite materials have the potential as biomimetic scaffolds for the regeneration of osteochondral defects.