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1.
Heliyon ; 10(12): e32837, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022059

RESUMO

This work aimed to produce silver nanoparticles (AgNPs) by efficient green synthesis techniques, namely rapid green synthesis and modified microwave-assisted green synthesis methods. The study used fish scale collagen (FsCol) as a stabilizer to assess its impact on the dimensions and configurations of AgNPs. Four samples were prepared with varying concentrations of FsCol. The synthesized AgNPs were characterized using Ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray diffraction analysis (XRD), Dynamic Light Scattering (DLS), and Transmission electron microscopy (TEM) techniques. The obtained sizes are as follows: 85 ± 15 nm, 70 ± 10 nm, 50 ± 10 nm, and 28-40 nm. The UV-vis spectroscopy revealed a shift in the absorbance peaks from 400 to 446 nm. The SEM method showed a spherical form in all of the samples. The element silver was detected in the EDX examination, along with the presence of oxygen (O) and carbon (C). The FTIR analysis revealed that the peaks seen at 3307 cm-1 were attributed to the stretching of O-H bonds, while the mountain at 1638 cm-1 belonged to the extension of N-H bonds (amide A). Additionally, the band observed at 1638 cm-1 indicated the presence of CO bonds (amide I).The 2140 cm-1 and 1302 cm-1 peaks may be attributed to the C2H2 group present in the plant components and the N-H bending (Amide III), respectively. The XRD pattern indicates that the synthesis process resulted in the formation of crystalline AgNPs. The particle sizes measured using DLS were 121 nm, 96.36 nm, 82.3 nm, and 48.50 nm. The TEM approach revealed that all samples had a spherical morphology with varying sizes: 80-100 nm, 50-80 nm, 40-60 nm, and 28-42 nm. The synthesized AgNPs were tested for their antibacterial properties against the pathogenic pathogens Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus). The influence of AgNPs on bacteria was amplified as the particle size decreased, resulting in a larger inhibitory zone for the smaller particles.

2.
Heliyon ; 9(5): e15838, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206015

RESUMO

The present study was conducted to prepare the fish scales' hydroxyapatite/collagen beads (FsHA/FsCol) and characterize their biological, physical, and chemical properties. A new method was used to prepare FsHA/FsCol composite beads by infiltrating the beads of FsHA in the solution of FsCol as a green method. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) analysis, Fourier-transform infrared (FTIR) spectroscopy analysis and energy dispersive X-ray analysis (EDX), used to evaluate the physical-chemical properties of the synthesized samples. Meanwhile, the cytotoxic and attachment studies of the FsHA/FsCol beads were used to investigate the biological features against the MG-63 human cell line. The results specified the efficiency of the new method, functional groups of FsCol were indicated to be present inside the beads of FsHA according to the XRD analysis which shows the functional peaks of FsCol. The SEM image were conformed successfully use starch as a porous agent to increasing the porous of the FsHA beads after adding 20 wt% of it. Alamar Blue assay has been used to evaluate the cytotoxicity of FsHA/FsCol beads the results were shown 87% average cell viability of the MG-63 human cell line on the beads and attached very well to the surface of the composites, indicating no toxicity being exerted by all the composites at high concentrations.

4.
ScientificWorldJournal ; 2020: 6957171, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33414690

RESUMO

Introduction. Trawling is a method of catching fish in a large volume where fish nets are pulled through water using one or two boats. Bottom trawling is where the nets are pulled over on the seabed. The gear of the bottom trawling would impact the exposed subsea pipeline, on the seabed. Subsea pipelines transport crude oil and gas from the offshore platform to shore facility. This study assesses the risk of fish trawling activities to the subsea pipelines at Sabah and Labuan offshore. The specification of trawl equipment used by local trawlers in Sabah was determined by the on-site survey. The frequency of a fish trawler crossing over the pipelines was calculated based interview on operation and site survey. The calculation of the pull-over load of the otter board was calculated using the DNVGL algorithm. The severity and frequency index of the risk matrix was developed based on literature review. Results showed that the pull-over load of the otter board would not damage the pipelines. The risk posed by the fish trawler activity to the pipelines is low and moderate.


Assuntos
Pesqueiros , Algoritmos , Malásia , Modelos Teóricos , Oceanos e Mares , Medição de Risco
5.
Tissue Eng Regen Med ; 16(3): 285-299, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31205857

RESUMO

Background: This study aimed to observe the cartilaginous matrix production in SRY (sex determining region Y)-box 9 (SOX9)- and/or telomerase reverse transcriptase (TERT)-transfected chondrocytes from monolayer to three-dimensional (3D) culture. Methods: The genes were transferred into chondrocytes at passage-1 (P1) via lipofection. The post-transfected chondrocytes (SOX9-, TERT- and SOX9/TERT) were analysed at P1, P2 and P3. The non-transfected group was used as control. The 3D culture was established using the chondrocytes seeded in a disc-shaped PLGA/fibrin and PLGA scaffolds. The resulting 3D "cells-scaffolds" constructs were analysed at week-1, -2 and -3. The histoarchitecture was evaluated using haematoxylin and eosin, alcian blue and safranin o stains. The quantitative sulphated glycosaminoglycan (sGAG) content was measured using biochemical assay. The cartilage-specific markers expression were analysed via real-time polymerase chain reaction. Results: All monolayer cultured chondrocytes showed flattened, fibroblast-like appearance throughout passages. Proteoglycan and sGAG were not detected at the pericellular matrix region of the chondrocytes. The sGAG content assay indicated the matrix production depletion in the culture. The cartilage-specific markers, COL2A1 and ACAN, were downregulated. However, the dedifferentiation marker, COL1A1 was upregulated. In 3D "cells-scaffolds" constructs, regardless of transfection groups, chondrocytes seeded in PLGA/fibrin showed a more uniform distribution and produced denser matrix than the PLGA group especially at week-3. Both sGAG and proteoglycan were clearly visualised in the constructs, supported by the increment of sGAG content, quantitatively. Both COL2A1 and ACAN were upregulated in SOX9/TERT-PLGA and SOX9/TERT-PLGA/fibrin respectively. While, COL1A1 was downregulated in SOX9/TERT-PLGA. Conclusion: These findings indicated that the SOX9/TERT-transfected chondrocytes incorporation into 3D scaffolds facilitates the cartilage regeneration which is viable structurally and functionally.


Assuntos
Condrócitos/metabolismo , Fatores de Transcrição SOX9/genética , Telomerase/genética , Transfecção , Agrecanas/genética , Agrecanas/metabolismo , Animais , Células Cultivadas , Condrócitos/citologia , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Fibrina , Fibroblastos/citologia , Regulação da Expressão Gênica , Glicosaminoglicanos , Proteoglicanas , Coelhos , Ratos , Alicerces Teciduais
6.
Int J Biol Macromol ; 111: 158-168, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29305219

RESUMO

The various composition multicomponent chitosan/fish collagen/glycerin 3D porous scaffolds were developed and investigated the effect of various composition chitosan/fish collagen/glycerin on scaffolds morphology, mechanical strength, biostability and cytocompatibility. The scaffolds were fabricated via freeze-drying technique. The effects of various compositions consisting in 3D scaffolds were investigated via FT-IR analysis, porosity, swelling and mechanical tests, and effect on the morphology of scaffolds investigated microscopically. The biostability and cytocompatibility tests were used to explore the ability of scaffolds to use for tissue engineering application. The average pore sizes of scaffolds were in range of 100.73±27.62-116.01±52.06, porosity 71.72±3.46-91.17±2.42%, tensile modulus in dry environment 1.47±0.08-0.17±0.03MPa, tensile modulus in wet environment 0.32±0.03-0.14±0.04MPa and biodegradation rate (at day 30) 60.38±0.70-83.48±0.28%. In vitro culture of human fibroblasts and keratinocytes showed that the various composition multicomponent 3D scaffolds were good cytocompatibility however, the scaffolds contained high amount of fish collagen excellently facilitated cell proliferation and adhesion. It was found that the high amount fish collagen and glycerin scaffolds have high porosity, enough mechanical strength and biostability, and excellent cytocompatibility.


Assuntos
Materiais Biocompatíveis/farmacologia , Quitosana/química , Colágeno/química , Engenharia Tecidual , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Quitosana/síntese química , Quitosana/farmacologia , Colágeno/síntese química , Colágeno/farmacologia , Fibroblastos/efeitos dos fármacos , Glicerol/síntese química , Glicerol/química , Glicerol/farmacologia , Humanos , Teste de Materiais , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Alicerces Teciduais/química , Torção Mecânica
7.
Int J Biol Macromol ; 104(Pt A): 1020-1029, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28668615

RESUMO

The zinc oxide nanoparticles (particles size <50nm) incorporated into chitosan-collagen 3D porous scaffolds and investigated the effect of zinc oxide nanoparticles incorporation on microstructure, mechanical properties, biodegradation and cytocompatibility of 3D porous scaffolds. The 0.5%, 1.0%, 2.0% and 4.0% zinc oxide nanoparticles chitosan-collagen 3D porous scaffolds were fabricated via freeze-drying technique. The zinc oxide nanoparticles incorporation effects consisting in chitosan-collagen 3D porous scaffolds were investigated by mechanical and swelling tests, and effect on the morphology of scaffolds examined microscopically. The biodegradation and cytocompatibility tests were used to investigate the effects of zinc oxide nanoparticles incorporation on the ability of scaffolds to use for tissue engineering application. The mean pore size and swelling ratio of scaffolds were decreased upon incorporation of zinc oxide nanoparticles however, the porosity, tensile modulus and biodegradation rate were increased upon incorporation of zinc oxide nanoparticles. In vitro culture of human fibroblasts and keratinocytes showed that the zinc oxide nanoparticles facilitated cell adhesion, proliferation and infiltration of chitosan-collagen 3D porous scaffolds. It was found that the zinc oxide nanoparticles incorporation enhanced porosity, tensile modulus and cytocompatibility of chitosan-collagen 3D porous scaffolds.


Assuntos
Materiais Biocompatíveis/farmacologia , Quitosana/química , Colágeno/química , Fenômenos Mecânicos , Nanopartículas/química , Alicerces Teciduais/química , Óxido de Zinco/química , Materiais Biocompatíveis/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Teste de Materiais , Tamanho da Partícula , Porosidade , Relação Estrutura-Atividade , Engenharia Tecidual
8.
Springerplus ; 2(1): 79, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23503998

RESUMO

Chitosan is a marine-derived product that has been widely used in clinical applications, especially in skin reconstruction. The mammalian scaffolds derived from bovine and porcine material have many limitations, for example, prion transmission and religious concerns. Therefore, we created a chitosan skin regenerating template (SRT) and investigated the behavior of fibroblast cell-scaffold constructs. Primary human dermal fibroblasts (HDF) were isolated and then characterized using vimentin and versican. HDF were seeded into chitosan SRT at a density of 3×10(6) cells/cm(2) for fourteen days. Histological analysis and live cells imaging revealed that the cell-chitosan constructs within interconnected porous chitosan showed significant interaction between the cells as well as between the cells and the chitosan. Scanning electron microscopy (SEM) analysis revealed cells spreading and covering the pores. As the pore sizes of the chitosan SRT range between 40-140 µm, an average porosity is about 93 ± 12.57% and water uptake ratio of chitosan SRT is 536.02 ± 14.29%, it is a supportive template for fibroblast attachment and has potential in applications as a dermal substitute.

9.
J Biosci Bioeng ; 115(4): 453-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23177217

RESUMO

The effects of locally produced chitosan (CPSRT-NC-bicarbonate) in the intervention of keloid pathogenesis were investigated in vitro. A human keratinocyte-fibroblast co-culture model was established to investigate the protein levels of human collagen type-I, III and V in a western blotting analysis, the secreted transforming growth factor-ß1 (TGF-ß1) in an enzyme-linked immunosorbent assay (ELISA) and the mRNA levels of TGF-ß1's intracellular signaling molecules (SMAD2, 3, 4 and 7) in a real-time PCR analysis. Keratinocyte-fibroblast co-cultures were maintained in DKSFM:DMEM:F12 (2:2:1) medium. Collagen type-I was found to be the dominant form in primary normal human dermal fibroblast (pNHDF) co-cultures, whereas collagen type-III was more abundant in primary keloid-derived human dermal fibroblast (pKHDF) co-cultures. Collagen type-V was present as a minor component in the skin. TGF-ß1, SMAD2 and SMAD4 were expressed more in the pKHDF than the pNHDF co-cultures. Co-cultures with normal keratinocytes suppressed collagen type-III, SMAD2, SMAD4 and TGF-ß1 expressions and CPSRT-NC-bicarbonate enhanced this effect. In conclusion, the CPSRT-NC-bicarbonate in association with normal-derived keratinocytes demonstrated an ability to reduce TGF-ß1, SMAD2 and SMAD4 expressions in keloid-derived fibroblast cultures, which may be useful in keloid intervention.


Assuntos
Materiais Biocompatíveis/farmacologia , Quitosana/farmacologia , Fibroblastos/metabolismo , Queloide/metabolismo , Queratinócitos/metabolismo , Proteínas Smad/metabolismo , Células Cultivadas , Técnicas de Cocultura , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo V/metabolismo , Derme/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Mesoderma/citologia , Modelos Biológicos , Regeneração , Transdução de Sinais/efeitos dos fármacos , Fenômenos Fisiológicos da Pele , Proteínas Smad/genética , Fator de Crescimento Transformador beta1/metabolismo
10.
Rev. MED ; 18(1): 23-31, ene.-jun. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-670838

RESUMO

El hueso es un tejido en constante cambio por procesos de remodelación y reparación, funciones realizadas por tres tipos celulares: los osteoblastos, los osteocitos y los osteoclastos. Los osteoclastos (OC) son células grandes, multinucleadas y ricas en anhidrasa carbónica y fosfatasa ácida resistente al tartrato (TRAP). Continuando con trabajos previos en los cuales se ha sintetizado apatita carbonatada (CAp) por precipitación de soluciones acuosas y por reacción del estado sólido, en este artículo se presentan los resultados del cultivo de osteoclastos y su efecto biológico sobre láminas sintetizadas de polietileno de baja densidad y CAp (PEBD-CAp). La inducción al linaje osteoclastogénico se realizó adicionando inductores específicos a cultivos de progenitores de la medula ósea de porcinos, a los que se les determinó la actividad de TRAP y la detección de los transcritos de los genes rank, c-src y cat-K. El cultivo sobre láminas PEBD-CAp permitió evidenciar la actividad osteoclástica sobre la cerámica a través de microscopia óptica y electrónica, demostrando su biodegradabilidad in vitro y complementando resultados previos sobre la osteoconductividad del material en un modelo in vivo en porcinos...


Bone tissue is in a continuous process of synthesis and resorption, functions that are performed by three main cell types: osteblasts, osteocytes and osteoclasts. Osteoclasts (OC) are big, multinucleate cells, producing carbonic anhydrase and tartrate-resistant acid phosphatase (TRAP). In continuation with previous works where CAp was synthesised by precipitation of aqueous solution and by solid state reaction, in this article the results of a culture of osteoclasts and its biological action over low-density polyethylene impregnated with carbonated apatite slides (LDPE-CAp) are shown. Osteoclast induction was achieved with the addition of specific inductors to cultures of porcine bone marrow progenitors, to which TRAP activity, detection of transcripts of rank, c-src and cat-K genes were determined. Cultures on LDPE-CAp slides analyzed with optical and electron microscopy demonstrated osteoclast activity and biodegradability of the ceramic, thus complementing previous studies on the osteoconductivity of this material in an in vivo porcine model...


O tecido ósseo está em constante mutação através dos processos de remodelação e reparação, funções executadas por três tipos de células: osteoblastos, osteócitos e osteoclastos. Osteoclastos (OC) são células grandes, multinucleadas e ricas em anidrase carbônica e fosfatase ácida resistente ao tartarato (TRAP). Na sequência dos trabalhos previos nos quais foi sintetizado apatita carbonatada (CAP) por precipitação a partir de soluções acuosas e reação em estado sólido, este artigo apresenta os resultados a cultura dos osteoclastos e seu efeito biológico sobre filmes sintetizados de polietileno de baixa densidade e Cap (PEBD-Cap). A indução da linhagem osteoclastogénico foi feito pela adição de indutores específicas a culturas progenitoras da medula óssea de porcos, nos quais foi determinada a atividade TRAP e a deteção de transcritos dos genes rank, c-src e cat-K. O cultivo em placas PEBD-Cap permitiu demonstrar a atividade osteoclástica em cerâmica por microscopia óptica e eletrônica, demosntrando a sua biodegradabilidade in vitro e complementando resultados anteriores sobre a osteocondutividade do material em um modelo de suínos in vivo...


Assuntos
Animais , Reabsorção Óssea , Osteoclastos , Polietileno
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