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1.
Biopolymers ; 114(10): e23562, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37421643

RESUMO

Polymeric barrier membranes are used in periodontal applications to prevent fibroblastic cell migration into the cavities of bone tissue and to properly guide the proliferation of tissues. In this study, the fabrication, characterization, bioactivity, and in vitro biological properties of polyvinyl alcohol-based nanofibrous membranes containing nano-sized 45S5 bioactive glass (BG) loaded with chlorhexidine (CH) gluconate with biocompatible, bioactive, and antibacterial properties for using as dental barrier membranes were investigated. Nanofibrous membranes with an average fiber diameter, pore size, and porosity of 210 nm, 24.73 µm, and 12.42%, respectively, were loaded with 1% and 2% CH, and the release profile was investigated. The presence of BG in the membranes promoted fibroblastic proliferation and the presence of CH provided antibacterial properties. Nanofibrous membranes exhibit a high ability to restrict bacterial growth while fulfilling the necessary conditions for use as a dental barrier thanks to their low swelling rates, significant surface bioactivities, and appropriate degradation levels.


Assuntos
Regeneração Tecidual Guiada , Nanofibras , Álcool de Polivinil/farmacologia , Clorexidina/farmacologia , Regeneração Óssea , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia
2.
Biomed Eng Online ; 15(1): 81, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27388324

RESUMO

BACKGROUND: We evaluated the Bovine hydroxyapatite (BHA) structure. BHA powder was admixed with 5 and 10 wt% natural pumice (NP). Compression strength, Vickers micro hardness, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction studies were performed on the final NP-BHA composite products. The cells proliferation was investigated by MTT assay and SEM. Furthermore, the antimicrobial activity of NP-BHA samples was interrogated. RESULTS: Variances in the sintering temperature (for 5 wt% NP composites) between 1000 and 1300 °C, reveal about 700 % increase in the microhardness (~100 and 775 HV, respectively). Composites prepared at 1300 °C demonstrate the greatest compression strength with comparable result for 5 wt% NP content (87 MPa), which are significantly better than those for 10 wt% and those that do not include any NP (below 60 MPa, respectively). CONCLUSION: The results suggested the optimal parameters for the preparation of NP-BHA composites with increased mechanical properties and biocompatibility. Changes in micro-hardness and compression strength can be tailored by the tuning the NP concentration and sintering temperature. NP-BHA composites have demonstrated a remarkable potential for biomedical engineering applications such as bone graft and implant.


Assuntos
Materiais Biocompatíveis/química , Engenharia Biomédica , Durapatita/química , Silicatos/química , Animais , Bovinos , Linhagem Celular Tumoral , Humanos , Teste de Materiais , Fenômenos Mecânicos , Porosidade , Temperatura
3.
Polymers (Basel) ; 16(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38399911

RESUMO

In bone tissue engineering, scaffold attributes such as pore dimensions and mechanical strength are crucial. This study synthesized polycaprolactone dimethacrylate (PCLDMA) from polycaprolactone (PCL), incorporating epichlorohydrin (Epi-PCL) and methacryloyl chloride (Meth-Cl). PCLDMA was blended with polylactic acid (p-PLA) to 3D-print bone scaffolds using stereolithography (SLA). Analytical techniques included nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and compression testing. Degradation kinetics and cell viability were investigated using human osteoblast (HOB) cells. Findings revealed PCLDMA/p-PLA composite scaffold superiority over the original polymers. Notably, PCLDMA-60 (60% PCLDMA, 40% p-PLA) displayed optimal properties. Compressive strength varied from 0.019 to 16.185 MPa, porosity from 2% to 50%, and degradation rates from 0% to 0.4% over three days. Cell viability assays affirmed biocompatibility across various PCLDMA ratios. In conclusion, PCLDMA/p-PLA composite scaffolds, particularly PCLDMA-60, show great potential in bone tissue engineering.

4.
Mar Pollut Bull ; 190: 114895, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37011539

RESUMO

The effects grain size on transport and retention of plastics in sediments are controversial issue. Four beaches were selected on the Bodrum Peninsula (SW Türkiye) for this study. Twenty-four samples with poorly to well sorted, sandy gravel, gravel, or gravelly sand were collected from the top five cm of the sampling quadrant's four corners and center of 1 m2 area, from shoreline and backshore. The highest plastic content (38 mesoplastics/600 g - 455 microplastics (MPs)/1200 g) was determined on the Bodrum Coast having the highest population. Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyethylene terephthalate (PET) and polyurethane (PU) were predominantly detected with Fourier Transform Infrared Spectroscopy (FTIR) analysis as MPs as a fragment and fiber. This study indicates the negative correlation between grain size and the number of MPs in coastal sediments. Anthropogenic activities are evaluated as a possible primary source of plastic pollution in the study area.


Assuntos
Plásticos , Poluentes Químicos da Água , Plásticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Microplásticos/análise , Polipropilenos/análise , Areia , Sedimentos Geológicos/análise
5.
J World Fed Orthod ; 12(2): 64-71, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36653263

RESUMO

BACKGROUND: Introducing three-dimensional (3D) printing has opened new visions in the orthodontic field. This research evaluates three-dimensionally produced orthodontic retainers and their future possible uses. For this purpose, in vitro tests were performed for these groups, including bond strength, failure analysis, discoloration, and biodegradation. METHODS: A total of 30 specimens (n = 30), lower incisor human teeth, were randomly divided into three groups for a bond strength failure analysis (for each group n = 10). In the experimental groups, lingual retainers were fabricated using 3D systems (group 1 with 3D dental pen and group 2 with 3D-printed). In the control group (group 3), the retainer system was a combination of a wire and composite, which is being used worldwide. A total of 30 specimens (n = 30) from the 3D dental pen and 3D-printed for discoloration and biodegradation tests were divided into three groups (water, tea, and coffee). Data were analyzed using the Mann-Whitney U test, ANOVA, and chi-square test. RESULTS: For all parameters tested, significant differences were determined among groups. The 3D pen group had the highest score for bond strength, whereas discoloration differed significantly. CONCLUSIONS: According to the limitations of this research, 3D-printed retainers have the potential for clinical use in the near future.


Assuntos
Colagem Dentária , Humanos , Testes Mecânicos , Desenho de Aparelho Ortodôntico , Contenções Ortodônticas , Fios Ortodônticos
6.
Carbohydr Polym ; 270: 118373, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364617

RESUMO

Dual-drug delivery systems were constructed through coaxial techniques, which were convenient for the model drugs used the present work. This study aimed to fabricate core-shell electrospun nanofibrous membranes displaying simultaneous cell proliferation and antibacterial activity. For that purpose, phenytoin (Ph), a well-known proliferative agent, was loaded into a polycaprolactone (PCL) shell membrane, and as-prepared silver-chitosan nanoparticles (Ag-CS NPs), as biocidal agents, were embedded in a polyvinyl alcohol (PVA) core layer. The morphology, chemical composition, mechanical and thermal properties of the nanofibrous membranes were characterized by FESEM/STEM, FTIR and DSC. The coaxial PVA-Ag CS NPs/PCL-Ph nanofibers (NFs) showed more controlled Ph release than PVA/PCL-Ph NFs. There was notable improvement in the morphology, thermal, mechanical, antibacterial properties and cytobiocompatibility of the fibers upon incorporation of Ph and Ag-CS NPs. The proposed core-shell PVA/PCL NFs represent promising scaffolds for tissue regeneration and wound healing by the effective dual delivery of phenytoin and Ag-CS NPs.


Assuntos
Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Nanofibras/química , Nanopartículas/química , Fenitoína/química , Prata/química , Antibacterianos/farmacologia , Varredura Diferencial de Calorimetria/métodos , Proliferação de Células/efeitos dos fármacos , Quitosana/farmacologia , Escherichia coli/efeitos dos fármacos , Microscopia Eletrônica de Varredura/métodos , Fenitoína/farmacologia , Poliésteres/química , Álcool de Polivinil/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
7.
J Integr Med ; 19(5): 451-459, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34417154

RESUMO

OBJECTIVE: Chemotherapeutic drugs, such as cisplatin (CP), which are associated with oxidative stress and apoptosis, may adversely affect the reproductive system. This study tests whether administration of propolis and nano-propolis (NP) can alleviate oxidative stress and apoptosis in rats with testicular damage induced by CP. METHODS: In this study, polymeric nanoparticles including propolis were synthesized with a green sonication method and characterized using Fourier transform-infrared spectroscopy, Brunauer-Emmett-Teller, and wet scanning transmission electron microscopy techniques. In total, 56 rats were divided into the following seven groups: control, CP, propolis, NP-10, CP + propolis, CP + NP-10, and CP + NP-30. Propolis (100 mg/kg), NP-10 (10 mg/kg), and NP-30 (30 mg/kg) treatments were administered by gavage daily for 21 d, and CP (3 mg/kg) was administered intraperitoneally in a single dose. After the experiment, oxidative stress parameters, namely, malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), and catalase (CAT), and apoptotic pathways including B cell leukemia/lymphoma-2 protein (Bcl-2) and Bcl-2-associated X protein (Bax) were measured in testicular tissues. Furthermore, sperm quality and weights of the testis, epididymis, right cauda epididymis, seminal vesicles and prostate were evaluated. RESULTS: Propolis and NP (especially NP-30) were able to preserve oxidative balance (decreased MDA levels and increased GSH, CAT, and GPx activities) and activate apoptotic pathways (decreased Bax and increased Bcl-2) in the testes of CP-treated rats. Sperm motility in the control, CP, and CP + NP-30 groups were 60%, 48.75%, and 78%, respectively (P < 0.001). Especially, NP-30 application completely corrected the deterioration in sperm features induced by CP. CONCLUSION: The results show that propolis and NP treatments mitigated the side effects of CP on spermatogenic activity, antioxidant situation, and apoptosis in rats.


Assuntos
Própole , Testículo , Animais , Antioxidantes/metabolismo , Cisplatino/toxicidade , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Motilidade dos Espermatozoides
8.
Data Brief ; 32: 106149, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32904227

RESUMO

Catal's reagent is characterized by spectroscopic methods such as fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), ultraviolet (UV)-visible spectrophotometry. Effects of different solvents such as methanol and ethanol on absorption spectrum of 1-(Dodecylthio)anthracene-9,10-dione (3) were present. Detection range of iron (II) sulfate using Catal's reagent was analyzed. Synthesis of 1-(Dodecylthio)anthracene-9,10-dione (3) was explained, and absorbances of various concentrations of iron (II) sulfate (0- 10 mg mL-1) were measured. The possible detection mechanism was also explained. The dataset is useful to improve the detection of iron (II) sulfate in various application fields such as environmental, agricultural, sensor, food, textile and cement industries. The study refers to: F. Ozkok, Y.M. Sahin, V. Enisoglu-Atalay, K. Asgarova, N. Onul, T. Catal, Sensitive Detection of Iron (II) Sulfate with a Novel Reagent using Spectrophotometry, Spectchim. Acta. A, 240 (2020), 118631. https://doi.org/10.1016/j.saa.2020.118631.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 240: 118631, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32619787

RESUMO

In this study, a novel reagent was developed for sensitive detection of iron (II) sulfate, spectrophotometrically. A novel thio-anthraquinone derivative, 1-(Dodecylthio)anthracene-9,10-dione (3), was synthesized from the chemical reaction of 1-Chloroanthraquinone (1) and 1-Dodecanethiol (2) by an original reaction method and was used in the preparation of the novel reagent called Catal's reagent. A synthesized thio-anthraquinone analogue (3) was purified by column chromatography, and its chemical structure was characterized by spectroscopic methods such as Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and ultraviolet (UV)-visible spectrophotometry. The chemical and molecular structure of the developed thio-antraquinone derivative (3) was illuminated using computational methods with the GaussView5 and Gaussian09 programs. Various solvents including ethanol, methanol, and acetonitrile were examined in the preparation of the reagent. A concentration range from 0.2 mg mL-1 up to 10 mg mL-1 of iron (II) sulfate heptahydrate solution in distilled water was prepared. The absorption spectra of Catal's reagent (0.816 mM) showed three peaks between 185 nm-700 nm of wavelength. However, after the reaction with H2O2 and the 30 mM trisodium citrate dihydrate mixture in the presence of an iron sulfate (II) solution, a single peak was observed, producing a stable and reddish/brownish homogenous solution (λ max = 304 nm). The following concentrations of iron (II) sulfate heptahydrate was examined using developed protocol and the reagent, and the concentrations were measured spectrophotometrically at 304 nm, 0.2-1 mg mL-1. Absorbances of reaction mixtures of iron (II) sulfate remained stable up to 48 h. The results indicated that the novel Catal's reagent can be used for sensitive spectrophotometric detection of iron (II) sulfate in aqueous solutions.

10.
Curr Pharm Des ; 21(37): 5301-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26377653

RESUMO

Material research and development studies are focused on different techniques of bringing out nanomaterials with desired characteristics and properties. From the point of view of materials development, nowadays scientists are strongly focused on obtaining materials with predefined characteristics and properties. The morphology control seems to be a determinant factor and increasing attention is devoted to this aspect. At this moment it is possible to engineer the material's features by using different methods and materials combination for both medical and industrial applications. In the applications of chemistry and synthesis, biology, mechanics, optics solar cells and microelectronics tailoring the adjustable parameters of stoichiometry, chemical structure, shape and segregation are evaluated and opens new fields. Because of the magnetic features of nanoparticles and durable particle size, less than 100 nm, this study is aiming to describe their uses in practical applications. That's why the whole hydrodynamic magnetic core shell topic will be reviewed on this paper. Additionally, the properties acting in general sight in solid-state physics are utilized for material selection and for defining issue connecting the core, shell structure and their producing properties. Here, in the study of core/shell nanoparticle various physical and chemical synthesis routes and the effect of electrospun method are briefly discussed. Starting from a real void of the scientific literature, the existent data related to the 1D magnetic electrospun materials are reviewed. The perspectives in the medical, environmental or energetic sector is great and bring some real advantages related to the 0D core@shell structures because both mechanical and biological properties are dependent on the morphology of the materials.


Assuntos
Magnetismo/métodos , Nanopartículas de Magnetita/química , Nanoestruturas/química , Humanos , Nanopartículas de Magnetita/uso terapêutico , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/terapia , Tamanho da Partícula
11.
Curr Med Chem ; 21(29): 3391-404, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24606500

RESUMO

The present review is intended to bring together the main advances in the field of nanostructured biomaterials with antimicrobial properties. It is generally accepted that the discovery of antibiotics was of great importance but, nowadays new antimicrobial agents are needed and/or their better administration routes. The limitation of the use of antibiotics is essential because of the following reasons: the excessive use of antibiotics leads to the development of antibiotic resistant microorganisms; there are some alternatives for many types of infections, many of these alternatives being less toxic and do not lead to antibiotic similar resistance. In compliance with the above presented, the use of antibiotic is recommended to be eliminated (when alternatives are available) or to be reduced by using combined therapy when possible or to administrate these drugs through targeted or loco-regional drug delivery systems.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Nanoestruturas/química , Animais , Antibacterianos/química , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Nanomedicina
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