Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Pharm Biopharm ; 190: 258-269, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37463633

RESUMO

Chronic wounds affect millions of people annually and have emotional and financial implications in addition to health issues. The current treatment for chronic wounds involves the repeated use of bandages and drugs such as antibiotics over an extended period. A cost-effective and convenient solution for wound healing is the development of drug-incorporated bandages. This study aimed to develop a biocompatible bandage made of drug-incorporated poly (lactic-co-glycolic acid) (PLGA) microparticles (MPs) and eggshell membrane (ESM) for cornea wound healing. ESM has desirable properties for wound healing and can be isolated from eggshells using acetic acid or ethylenediaminetetraacetic acid (EDTA) protocols. Fluorescein isothiocyanate-labelled Bovine Serum Albumin (FITC-BSA) was used as a model drug, and the PLGA MPs were fabricated using a solvent extraction method. The MPs were successfully attached to the fibrous layer of the ESM using NaOH. The surface features of the ESM samples containing MPs were studied using a field emission scanning electron microscope (FESEM) and compared with blank ESM images. The findings indicated that the MPs were attached to the ESM fibres and had similar shapes and sizes as the control MPs. The fibre diameters of the MPs samples were assessed using Fiji-ImageJ software, and no significant changes were observed compared to the blank ESM. The surface roughness, Ra values, of the MPs incorporated ESM samples were evaluated and compared to the blank ESM, and no significant changes were found. Fourier transform infrared (FTIR) spectroscopy was used to analyse the chemical Composition of the bandage, and the spectra showed that the FBM were effectively incorporated into the ESM. The FTIR spectra identified the major peaks of the natural ESM and the PLGA polymer in the bandage. The bandage was transparent but had a reduced visibility in the waterproof test card method. The bandage achieved sustained drug release up to 10 days and was found to be biocompatible and non-toxic in a chorioallantoic membrane (CAM) assay. Overall, the drug-incorporated PLGA MPs-ESM bandage has great potential for treating chronic wounds.


Assuntos
Materiais Biocompatíveis , Casca de Ovo , Animais , Humanos , Materiais Biocompatíveis/química , Bandagens , Cicatrização , Antibacterianos/química
2.
Biomed Mater ; 18(4)2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37146617

RESUMO

Naturally derived materials are often preferred over synthetic materials for biomedical applications due to their innate biological characteristics, relative availability, sustainability, and agreement with conscientious end-users. The chicken eggshell membrane (ESM) is an abundant resource with a defined structural profile, chemical composition, and validated morphological and mechanical characteristics. These unique properties have not only allowed the ESM to be exploited within the food industry but has also led to it be considered for other novel translational applications such as tissue regeneration and replacement, wound healing and drug delivery. However, challenges still exist in order to enhance the native ESM (nESM): the need to improve its mechanical properties, the ability to combine/join fragments of ESM together, and the addition or incorporation of drugs/growth factors to advance its therapeutic capacity. This review article provides a succinct background to the nESM, its extraction, isolation, and consequent physical, mechanical and biological characterisation including possible approaches to enhancement. Moreover, it also highlights current applications of the ESM in regenerative medicine and hints at future novel applications in which this novel biomaterial could be exploited to beneficial use.


Assuntos
Galinhas , Casca de Ovo , Animais , Casca de Ovo/química , Materiais Biocompatíveis/química , Medicina Regenerativa , Sistemas de Liberação de Medicamentos
3.
J Funct Biomater ; 14(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37754864

RESUMO

The eggshell membrane (ESM) is a natural biomaterial with unique physical and mechanical properties that make it a promising candidate for wound-healing applications. However, the ESM's inherent properties can be enhanced through incorporation of silver nanoparticles (AgNPs), which have been shown to have antimicrobial properties. In this study, commercially produced AgNPs and green-processed AgNPs were incorporated into ESM and evaluated for their physical, biological, and antimicrobial properties for potential dermal application. The ESM was extracted using various techniques, and then treated with either commercially produced AgNPs (Sigma-Aldrich, Poole, UK) or green-synthesized AgNPs (Metalchemy, London, UK) to produce AgNPs-ESM samples. The physical characteristics of the samples were evaluated using scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, and the biological properties were assessed through in vitro studies using human dermal fibroblasts (HDFs) and BJ cells. The SEM analysis of the AgNPs-ESM samples showed localization of AgNPs on the ESM surface, and that the ESM maintained its structural integrity following AgNP incorporation. The FTIR confirmed loading of AgNPs to ESM samples. The biological studies showed that the 5 µg/mL AgNPs-ESM samples were highly biocompatible with both HDFs and BJ cells, and had good viability and proliferation rates. Additionally, the AgNPs-ESM samples demonstrated pro-angiogenic properties in the CAM assay, indicating their potential for promoting new blood vessel growth. Assessment of the antimicrobial activity of the enhanced AgNPs/ESMs was validated using the International Standard ISO 16869:2008 methodology and exploited Cladosporium, which is one of the most commonly identified fungi in wounds, as the test microorganism (≥5 × 106 cells/mL). The AgNPs-ESM samples displayed promising antimicrobial efficacy as evidenced by the measured zone of inhibition. Notably, the green-synthesized AgNPs demonstrated greater zones of inhibition (~17 times larger) compared to commercially available AgNPs (Sigma-Aldrich). Although both types of AgNP exhibited long-term stability, the Metalchemy-modified samples demonstrated a slightly stronger inhibitory effect. Overall, the AgNPs-ESM samples developed in this study exhibited desirable physical, biological, and antimicrobial properties for potential dermal wound-dressing applications. The use of green-processed AgNPs in the fabrication of the AgNPs-ESM samples highlights the potential for sustainable and environmentally friendly wound-healing therapies. Further research is required to assess the long-term biocompatibility and effectiveness of these biomaterials in vivo.

4.
Implement Sci Commun ; 4(1): 138, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968768

RESUMO

BACKGROUND: Maternal mortality remains stubbornly high in Ghana. Current national efforts are focused on improving the quality of care offered in health facilities. Obstetric triage is one intervention that has been proposed to improve the timeliness and appropriateness of care, two key elements of quality. In this study, we describe and evaluate a theory-based implementation approach to introduce obstetric triage into Tema General Hospital, a high-volume maternity hospital in Greater Accra, that blends concepts from implementation science and quality improvement. This implementation project was a first attempt to scale this intervention into a new facility, following initial development in the Greater Accra Regional Hospital (formerly Ridge Hospital) in Accra. METHODS: This was a retrospective mixed-methods evaluation of two stages of implementation: active implementation and sustainment. We triangulated monitoring data captured during active implementation with clinical outcome data (timeliness of first assessment, accuracy of diagnosis, and appropriateness of care plan) from direct observation or patient obstetric triage assessment forms at baseline, at the completion of the active implementation stage, and following a 12-month "washout" period with no contact between hospital staff and the purveyor organization. Finally, we assessed embeddedness of the new triage procedures using the NoMad, a quantitative assessment of constructs from normalization process theory (NPT). RESULTS: Patient waiting time decreased substantially during the study. At baseline, the median arrival-to-assessment waiting time was 70.5 min (IQR: 30.0-443.0 min). Waiting time decreased to 6.0 min (IQR: 3.0-15.0 min) following active implementation and to 5.0 min (IQR: 2.0-10.0 min) during the sustainment period. Accuracy of diagnosis was high at the end of active implementation (75.7% correct) and improved during the sustainment period (to 77.9%). The appropriateness of care plans also improved during the sustainment period (from 66.0 to 78.9%). Per NoMad data, hospital staff generally perceive obstetric triage to be well integrated into the facility. CONCLUSIONS: This theory-based implementation approach proved to be successful in introducing a novel obstetric triage concept to a busy high-volume hospital, despite resource constraints and a short implementation window. Results proved long-lasting, suggesting this approach has high potential for engendering sustainability in other facilities as well. Our approach will be useful to other initiatives that aim to utilize program data to create and test implementation theories.

5.
Pharmaceutics ; 14(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36297596

RESUMO

Current therapeutic treatments for the repair and/or replacement of damaged skin following disease or traumatic injury is severely limited. The chicken eggshell membrane (ESM) is a unique material: its innate physical and mechanical characteristics offer optimal barrier properties and, as a naturally derived extract, it demonstrates inherent biocompatibility/biodegradability. To further enhance its therapeutic and clinical potential, the ESM can be modified with the thermo-responsive polymer, poly(N-isopropylacrylAmide) (PNIPAAm) as well as the incorporation of (drug-loaded) silver nanoparticles (AgNP); essentially, by a simple change in temperature, the release and delivery of the NP can be targeted and controlled. In this study, ESM samples were isolated using a decellularization protocol, and the physical and mechanical characteristics were profiled using SEM, FT-IR, DSC and DMA. PNIPAAm was successfully grafted to the ESM via amidation reactions and confirmed using FT-IR, which demonstrated the distinctive peaks associated with Amide A (3275 cm−1), Amide B (2970 cm−1), Amide I (1630 cm−1), Amide II (1535 cm−1), CH2, CH3 groups, and Amide III (1250 cm−1) peaks. Confirmation of the incorporation of AgNP onto the stratified membrane was confirmed visually with SEM, qualitatively using FT-IR and also via changes in absorbance at 380 nm using UV-Vis spectrophotometry during a controlled release study for 72 h. The biocompatibility and cytotoxicity of the novel constructs were assessed using human dermal fibroblast (HDFa) and mouse dermal fibroblast (L929) cells and standard cell culture assays. Metabolic activity assessment (i.e., MTS assay), LDH-release profiles and Live/Dead staining demonstrated good attachment and spreading to the samples, and high cell viability following 3 days of culture. Interestingly, longer-term viability (>5 days), the ESM-PNIPAAm and ESM-PNIPAAm (AgNP) samples showed a greater and sustained cell viability profile. In summary, the modified and enhanced ESM constructs were successfully prepared and characterized in terms of their physical and mechanical profiles. AgNP were successfully loaded into the construct and demonstrated a desirable release profile dependent on temperature modulation. Fibroblasts cultured on the extracted ESM samples and ESM-PNIPAAm demonstrated high biocompatibility in terms of high cell attachment, spreading, viability and proliferation rates. As such, this work summarizes the development of an enhanced ESM-based construct which may be exploited as a clinical/therapeutic wound dressing as well as a possible application as a novel biomaterial scaffold for drug development.

6.
J Biomater Appl ; 36(5): 912-929, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34139891

RESUMO

The eggshell membrane (ESM) is an abundant resource with innate complex structure and composition provided by nature. With at least 60 million tonnes of hen eggs produced globally per annum, utilisation of this waste resource is highly attractive in positively impacting sustainability worldwide. Given the morphology and mechanical properties of this membrane, it has great potential as a biomaterials for wound dressing. However, to date, no studies have demonstrated nor reported this application. As such, the objective of this investigation was to identify and optimise a reproducible extraction protocol of the ESM and to assess the physical, chemical, mechanical and biological properties of the substrate with a view to use as a wound dressing. ESM samples were isolated by either manual peeling (ESM-strip) or via extraction using acetic acid [ESM-A0.5] or ethylenediaminetetraacetic acid, EDTA [ESM-E0.9]. Energy dispersive X-ray spectroscopy (EDS) confirmed that there were no traces of calcium residues from the extraction process. Fourier transform infrared (FTIR) spectroscopy revealed that the extraction method (acetic acid and EDTA) did not alter the chemical structures of the ESM and also clarified the composition of the fibrous proteins of the ESM. Scanning electron microscopy (SEM) analyses revealed a three-layer composite structure of the ESM: an inner layer as continuous, dense and non-fibrous (limiting membrane), a middle layer with a network of fibres (inner shell membrane) and the outer layer (outer shell membrane) of larger fibres. Material properties including optical transparency, porosity, fluid absorption/uptake, thermal stability, mechanical profiling of the ESM samples were performed and demonstrated suitable profiles for translational applications. Biological in vitro studies using SV40 immortalised corneal epithelial cells (ihCEC) and corneal mesenchymal stromal cells (C-MSC) demonstrated excellent biocompatibility. Taken together, these results document the development of a novel sustainable biomaterial that may be used for ophthalmic wounds and/or other biomedical therapies.


Assuntos
Materiais Biocompatíveis/química , Lesões da Córnea/terapia , Casca de Ovo/química , Cicatrização , Animais , Bandagens , Biomimética , Técnicas de Cultura de Células , Galinhas , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA