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1.
Environ Toxicol Pharmacol ; 106: 104361, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211665

RESUMO

Thimerosal, a preservative commonly used in the pharmaceutical and cosmetic industry, has raised concerns regarding its potentially toxic effects as an organic mercury compound. Within this context, using an NMR-based metabolomics profile and chemometric analysis, zebrafish embryos were used as an in vivo model to study the effects of thimerosal in metabolic profiles after exposure to sublethal concentrations of the mercury compound. The thimerosal concentrations of 40 and 80 nM were employed, corresponding to 40% and 80% of the LC50, respectively, for zebrafish embryos. The most significant alterations in the metabolic profile included changes in carbohydrates, amino acids, nucleotides, trimethylamine-N-oxide, ethanolamine, betaine, and ethanol. Furthermore, thimerosal exposure affects various metabolic pathways, impairing the nervous system, disrupting protein metabolism, and potentially causing oxidative damage. Therefore, adopting a metabolomics approach in this investigation provided insights into the potentially implicated metabolic pathways contributing to the deleterious effects of thimerosal in biological systems.


Assuntos
Mercúrio , Peixe-Zebra , Animais , Timerosal/toxicidade , Metabolômica , Aminoácidos
2.
Chemosphere ; 342: 140167, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37717917

RESUMO

Among emerging layered materials, 2D transition metal dichalcogenides (TMDs) nanosheets (n-sheets) have received increasing attention for optoelectronics, energy storage, and, recently, for bioremediation and advanced biomedical applications; however, a lack of ecotoxicological in vivo studies is evident. Herein, for the first time, the potential nanotoxicity of liquid phase exfoliated Group VI TMDs n-sheets (MoS2, WS2, WSe2, and MoSe2) was comparatively investigated using zebrafish embryos (Z-EBs) as an in-vivo model. The 2D n-sheets were produced directly in aqueous-medium, the obtained n-sheets were characterized by scanning electron microscopy, Raman and visible spectroscopy, and their potential nanotoxicity was investigated by fish embryo test OECD TG 236. Chorionated and dechorionated embryos were used to assess the severity of TMD exposure. The survival rate, sublethal alteration during embryogenesis, hatching rate, and mortality were evaluated. TMDs n-sheets tend to adhere to the Z-EBs surface depending on their chemistry. Despite this, TMDs did not show lethal effects; weak sublethal effects were found for MoS2 and WSe2, while slight hatching delays were registered for MoSe2 and WSe2. The observed effects are attributable to the TMDs' tendency to interact with Z-EBs, because of the different chemistry. This work demonstrates how water-dispersed TMDs are potential eco/biocompatible materials.


Assuntos
Molibdênio , Peixe-Zebra , Animais , Molibdênio/toxicidade , Materiais Biocompatíveis , Ecotoxicologia , Metais
3.
Braz. j. biol ; 83: 1-8, 2023. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468848

RESUMO

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin along with marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.


Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.


Assuntos
Animais , Camundongos , Camundongos/anatomia & histologia , Camundongos/sangue , Origanum/toxicidade , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
4.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469064

RESUMO

Abstract Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin alongwith marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.


Resumo Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.

5.
Braz. j. biol ; 83: e244551, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285626

RESUMO

Abstract Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin alongwith marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.


Resumo Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.


Assuntos
Animais , Coelhos , Óleos Voláteis , Origanum , Anti-Infecciosos/toxicidade , Extratos Vegetais/toxicidade , Fígado , Antioxidantes
6.
Int J Nanomedicine ; 17: 6347-6376, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36540376

RESUMO

Background: Alzheimer's disease (AD) is one of the furthermost advanced neurodegenerative disorders resulting in cognitive and behavioral impairment. Citicoline sodium (CIT) boosts the brain's secretion of acetylcholine, which aids in membrane regeneration and repair. However, it suffers from poor blood-brain barrier (BBB) permeation, which results in lower levels of CIT in the brain. Purpose: This study targeted to encapsulate CIT into novel nano-platform transbilosomes decorated with hyaluronic acid CIT-HA*TBLs to achieve enhanced drug delivery from the nose to the brain. Methods: A method of thin-film hydration was utilized to prepare different formulae of CIT-TBLs using the Box-Behnken design. The optimized formula was then hyuloranated via integration of HA to form the CIT-HA*TBLs formula. Furthermore, AD induction was performed by aluminum chloride (Alcl3), animals were allocated, and brain hippocampus tissue was isolated for ELISA and qRT-PCR analysis of malondialdehyde (MDA), nuclear factor kappa B (NF-kB), and microRNA-137 (miR-137) coupled with immunohistochemical amyloid-beta (Aß1-42) expression and histopathological finding. Results: The hyuloranated CIT-HA*TBLs formula, which contained the following ingredients: PL (300 mg), Sp 60 (43.97 mg), and SDC (20 mg). They produced spherical droplets at the nanoscale (178.94 ±12.4 nm), had a high entrapment efficiency with 74.92± 5.54%, had a sustained release profile of CIT with 81.27 ±3.8% release, and had ex vivo permeation of CIT with 512.43±19.58 µg/cm2. In vivo tests showed that CIT-HA*TBL thermogel dramatically reduces the hippocampus expression of miR-137 and (Aß1-42) expression, boosting cholinergic neurotransmission and decreasing MDA and NF-kB production. Furthermore, CIT-HA*TBLs thermogel mitigate histopathological damage in compared to the other groups. Conclusion: Succinctly, the innovative loading of CIT-HA*TBLs thermogel is a prospectively invaluable intranasal drug delivery system that can raise the efficacy of CIT in Alzheimer's management.


Assuntos
Doença de Alzheimer , MicroRNAs , Ratos , Animais , Doença de Alzheimer/tratamento farmacológico , Portadores de Fármacos/uso terapêutico , Citidina Difosfato Colina/farmacologia , Citidina Difosfato Colina/uso terapêutico , Ácido Hialurônico/farmacologia , NF-kappa B , Encéfalo , Sódio/uso terapêutico
7.
Drug Deliv ; 29(1): 1582-1594, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35612286

RESUMO

Employment of mesoporous silica nanostructures (MSNs) in the drug delivery field has shown a significant potential for improving the oral delivery of active pharmaceutical products with low solubility in water. Mirtazapine (MRT) is a tetracyclic antidepressant with poor water solubility (BCS Class II), which was recently approved as a potent drug used to treat severe depression. The principle of this research is to optimize the incorporation of Mirtazapine into MSNs to improve its aqueous solubility, loading efficiency, release performance, and subsequent bioavailability. The formulation was optimized by using of Box-Behnken Design, which allows simultaneous estimation of the impact of different types of silica (SBA-15, MCM-41, and Aluminate-MCM-41), a different drug to silica ratios (33.33%, 49.99%, and 66.66%), and different drug loading procedures (Incipient wetness, solvent evaporation, and solvent impregnation) on the MRT loading efficiency, aqueous solubility and dissolution rate. The optimized formula was achieved by loading MRT into SBA-15 at 33.33% drug ratio prepared by the incipient wetness method, which displayed a loading efficiency of 104.05%, water solubility of 0.2 mg/ml, and 100% dissolution rate after 30 min. The pharmacokinetic profile of the optimized formula was obtained by conducting the in-vivo study in rabbits which showed a marked improvement (2.14-fold) in oral bioavailability greater than plain MRT. The physicochemical parameters and morphology of the optimized formula were characterized by; gas adsorption manometry, scanning electron microscopy (SEM), polarized light microscopy (PLM), Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRPD).


Assuntos
Portadores de Fármacos , Nanoestruturas , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Mirtazapina , Porosidade , Coelhos , Dióxido de Silício/química , Solubilidade , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química , Difração de Raios X
8.
Artigo em Inglês | MEDLINE | ID: mdl-34886364

RESUMO

Transgenders (TGs) are individuals with gender identity and behaviour different from the social norms; they often undergo gender-affirming hormone therapy (HT). HT for TG men involves testosterone treatment and, for TG women, oestrogen plus androgen-lowering agents. Due-but not limited-to the lifelong lasting HT, usually TG people experience several physical and behavioural conditions leading to different and specific susceptibility and vulnerability in comparison to general population, including the response to chemical contaminants present in daily life. In particular, the exposure to the widespread endocrine disrupters (EDs) may affect hormonal and metabolic processes, leading to tissue and organ damage. Since the endocrine system of TG people is overstimulated by HT and, often, the targets overlap with ED, it is reasonable to hypothesize that TG health deserves special attention. At present, no specific tools are available to study the toxicological effects of environmental contaminants, including EDs, and the potential long-term consequences of HT on TG people. In this context, the development of adequate and innovative animal models to mimic gender-affirming HT have a high priority, since they can provide robust data for hazard identification in TG women and men, leading to more reliable risk assessment.


Assuntos
Pessoas Transgênero , Animais , Feminino , Identidade de Gênero , Humanos , Masculino , Medição de Risco , Roedores , Testosterona
9.
J Transl Med ; 19(1): 276, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183031

RESUMO

BACKGROUND: Dental implants are considered the gold standard replacement for missing natural teeth. The successful clinical performance of dental implants is due to their ability to osseointegrate with the surrounding bone. Most dental implants are manufactured from Titanium and it alloys. Titanium does however have some shortcomings so alternative materials are frequently being investigated. Effective preclinical studies are essential to transfer the innovations from the benchtop to the patients. Many preclinical studies are carried out in the extra-oral bones of small animal models to assess the osseointegration of the newly developed materials. This does not simulate the oral environment where the dental implants are subjected to several factors that influence osseointegration; therefore, they can have limited clinical value. AIM: This study aimed to develop an appropriate in-vivo model for dental implant research that mimic the clinical setting. The study evaluated the applicability of the new model and investigated the impact of the surgical procedure on animal welfare. MATERIALS AND METHODS: The model was developed in male New Zealand white rabbits. The implants were inserted in the extraction sockets of the secondary incisors in the maxilla. The model allows a split-mouth comparative analysis. The implants' osseointegration was assessed clinically, radiographically using micro-computed tomography (µ-CT), and histologically. A randomised, controlled split-mouth design was conducted in 6 rabbits. A total of twelve implants were inserted. In each rabbit, two implants; one experimental implant on one side, and one control implant on the other side were applied. Screw-shaped implants were used with a length of 8 mm and a diameter of 2 mm. RESULTS: All the rabbits tolerated the surgical procedure well. The osseointegration was confirmed clinically, histologically and radiographically. Quantitative assessment of bone volume and mineral density was measured in the peri-implant bone tissues. The findings suggest that the new preclinical model is excellent, facilitating a comprehensive evaluation of osseointegration of dental implants in translational research pertaining to the human application. CONCLUSION: The presented model proved to be safe, reproducible and required basic surgical skills to perform.


Assuntos
Implantes Dentários , Osseointegração , Animais , Humanos , Masculino , Modelos Anatômicos , Projetos Piloto , Coelhos , Microtomografia por Raio-X
10.
J Cardiovasc Transl Res ; 13(5): 796-805, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040766

RESUMO

Degradable heart valves based on in situ tissue regeneration have been proposed as potentially durable and non-thrombogenic prosthetic alternatives. We evaluated the acute in vivo function, microstructure, mechanics, and thromboresistance of a stentless biodegradable tissue-engineered heart valve (TEHV) in the tricuspid position. Biomimetic stentless tricuspid valves were fabricated with poly(carbonate urethane)urea (PCUU) by double-component deposition (DCD) processing to mimic native valve mechanics and geometry. Five swine then underwent 24-h TEHV implantation in the tricuspid position. Echocardiography demonstrated good leaflet motion and no prolapse and trace to mild regurgitation in all but one animal. Histology revealed patches of proteinaceous deposits with no cellular uptake. SEM demonstrated retained scaffold microarchitecture with proteinaceous deposits but no platelet aggregation or thrombosis. Explanted PCUU leaflet thickness and mechanical anisotropy were comparable with native tricuspid leaflets. Bioinspired, elastomeric, stentless TEHVs fabricated by DCD were readily implantable and demonstrated good acute function in the tricuspid position.


Assuntos
Elastômeros/química , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Poliuretanos/química , Valva Tricúspide/cirurgia , Animais , Implante de Prótese de Valva Cardíaca/efeitos adversos , Hemodinâmica , Teste de Materiais , Modelos Animais , Desenho de Prótese , Sus scrofa , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiopatologia , Valva Tricúspide/ultraestrutura , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/fisiopatologia
11.
J Biomed Mater Res B Appl Biomater ; 107(2): 388-399, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29656599

RESUMO

Copper (Cu)-doped calcium silicate nanoparticles were synthesized by a wet precipitation method as economical bone fracture filler. The aim was to improve the overall physicochemical properties, bioactivity, and biological performance of the bone fracture filler prepared herein. The synthesized nanoparticles were evaluated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). The bioactivity of the prepared nanoparticles was investigated after immersion in simulated body fluid (SBF) by means of inductively coupled plasma (ICP), SEM coupled with energy dispersive X-rays (EDX), and FTIR. The size and bioactivity of the prepared nanoparticles after 15 days of immersion in SBF was dependent on the Cu concentrations. The fracture healing ability of the fabricated nanoparticles on adult aged male Wistar rats was enhanced by the presence of copper. All the obtained results are of high relevance for fabricating improved Cu-doped calcium silicate nanoparticles (∼50 nm) as low cost bone fracture filler. In addition, the in vivo study presented complete healing of the tibiae bone with normal architecture of bone tissue specifically calcium silicate nanoparticles doped with 3% and 5% Cu. Hence, the presence of copper is a promising tactic for improving the biological properties of calcium silicate. Therefore, the designed nanoparticles have huge potential for the treatment of bone fractures. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 388-399, 2019.


Assuntos
Compostos de Cálcio , Cobre , Consolidação da Fratura/efeitos dos fármacos , Fraturas Ósseas/tratamento farmacológico , Teste de Materiais , Nanopartículas , Silicatos , Animais , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Cobre/química , Cobre/farmacologia , Fraturas Ósseas/patologia , Masculino , Nanopartículas/química , Nanopartículas/uso terapêutico , Ratos , Ratos Wistar , Silicatos/química , Silicatos/farmacologia
12.
J Biomed Opt ; 22(9): 1-9, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28914008

RESUMO

The response of a fiber optic sensor [linearly chirped fiber Bragg grating (LCFBG)] to a linear thermal gradient applied on its sensing length (i.e., 1.5 cm) has been investigated. After these bench tests, we assessed their feasibility for temperature monitoring during thermal tumor treatment. In particular, we performed experiments during ex vivo laser ablation (LA) in pig liver and in vivo thermal ablation in animal models (pigs). We investigated the following: (i) the relationship between the full width at half maximum of the LCFBG spectrum and the temperature difference among the extremities of the LCFBG and (ii) the relationship between the mean spectrum wavelength and the mean temperature acting on the LCFBG sensing area. These relationships showed a linear trend during both bench tests and LA in animal models. Thermal sensitivity was significant although different values were found with regards to bench tests and animal experiments. The linear trend and significant sensitivity allow hypothesizing a future use of this kind of sensor to monitor both temperature gradient and mean temperature within a tissue undergoing thermal treatment.


Assuntos
Tecnologia de Fibra Óptica , Terapia a Laser , Fígado/cirurgia , Temperatura , Animais , Hipertermia Induzida , Suínos
13.
J Tissue Eng Regen Med ; 11(4): 1034-1044, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-25712330

RESUMO

Poly(ether imide) (PEI), which can be chemically functionalized with biologically active ligands, has emerged as a potential biomaterial for medical implants. Electrospun PEI scaffolds have shown advantageous properties, such as enhanced endothelial cell adherence, proliferation and low platelet adhesion in in vitro experiments. In this study, the in vivo behaviour of electrospun PEI scaffolds and PEI films was examined in a murine subcutaneous implantation model. Electrospun PEI scaffolds and films were surgically implanted subcutaneously in the dorsae of mice. The surrounding subcutaneous tissue response was examined via histopathological examination at 7 and 28 days after implantation. No serious adverse events were observed for both types of PEI implants. The presence of macrophages or foreign body giant cells in the vicinity of the implants and the formation of a fibrous capsule indicated a normal foreign body reaction towards PEI films and scaffolds. Capsule thickness and inflammatory infiltration cells significantly decreased for PEI scaffolds during days 7-28 while remaining unchanged for PEI films. The infiltration of cells into the implant was observed for PEI scaffolds 7 days after implantation and remained stable until 28 days of implantation. Additionally some, but not all, PEI scaffold implants induced the formation of functional blood vessels in the vicinity of the implants. Conclusively, this study demonstrates the in vivo biocompatibility of PEI implants, with favourable properties of electrospun PEI scaffolds regarding tissue integration and wound healing. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Materiais Biocompatíveis/farmacologia , Polímeros/farmacologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Reação a Corpo Estranho/patologia , Inflamação/patologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Teste de Materiais , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/efeitos dos fármacos , Polímeros/química , Temperatura
14.
Artif Cells Nanomed Biotechnol ; 44(8): 1793-1802, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26584819

RESUMO

CONTEXT: Tramadol is a centrally acting analgesic and requires frequent dosing. Hence, judicious selection of retarding formulations is necessary. Transdermal ethosomal gel delivery has been recognized as an alternative route to oral delivery. OBJECTIVE: The objective was to develop statistically optimized ethosomal systems for enhanced transdermal activity of tramadol vis-à-vis traditional liposomes. MATERIALS AND METHODS: Box-Behnken design was employed for optimization of nanoethosomes using phospholipon 90G (A), ethanol (B), and sonication time (C) as independent variables while dependent variables were the vesicle size (Y1), entrapment efficiency (Y2), and flux (Y3). It was prepared by rotary evaporation method and characterized for various parameters including entrapment efficiency, size and transflux. Preclinical assessments were conducted on Wistar rats to measure the performance of developed formulations. RESULTS: The optimized formulation provided mean vesicles size, reasonable entrapment efficiency and enhanced flux when compared with liposome (control). In-vivo absorption study showed a significant increase in bioavailability (7.51 times) compared with oral tramadol. The average primary irritancy index was found to be 1.4, indicating it to be non-irritant and safe for use. DISCUSSION AND CONCLUSION: The results also demonstrated that encapsulated tramadol increases its biological activity due to the superior skin penetration potential. The preclinical study indicates a significant (P < 0.05) extended analgesic effect compared to oral solution using the hot plate test method. The overall results suggest that developed formulation is an efficient carrier for transdermal delivery of tramadol.


Assuntos
Analgésicos Opioides , Tramadol , Administração Tópica , Analgésicos Opioides/química , Analgésicos Opioides/farmacocinética , Analgésicos Opioides/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Lipossomos , Ratos , Ratos Wistar , Absorção Cutânea , Tramadol/química , Tramadol/farmacocinética , Tramadol/farmacologia
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