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1.
Antioxidants (Basel) ; 11(11)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36358560

RESUMO

Skin wound healing is a complex process that requires the mutual work of cellular and molecular agents to promote tissue restoration. In order to improve such a process, especially in cases of impaired healing (e.g., diabetic ulcer, chronic wounds), there is a search for substances with healing properties and low toxicity: two features that some natural products-such as the bee product named propolis-exhibit. Propolis is a resinous substance obtained from plant resins and exudates with antioxidant, anti-inflammatory, and antitumoral activities, among other biological ones. Based on the previously reported healing actions of different types of propolis, the Brazilian red propolis (BRP) was tested for this matter. A skin wound excision model in male Wistar rats was performed using two topical formulations with 1% red propolis as treatments: hydroalcoholic extract and Paste. Macroscopical, histological and immunohistochemical analysis were performed, revealing that red propolis enhanced wound contraction, epithelialization, reduced crust formation, and modulated the distribution of healing associated factors, mainly collagen I, collagen III, MMP-9, TGF-ß3 and VEGF. Biochemical analysis with the antioxidants SOD, MPO, GSH and GR showed that propolis acts similarly to the positive control, collagenase, increasing these molecules' activity. These results suggest that BRP promotes enhanced wound healing by modulating growth factors and antioxidant molecules related to cutaneous wound healing.

2.
Mol Biol Rep ; 49(8): 7731-7741, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35716291

RESUMO

BACKGROUND: The human Amniotic Membrane (hAM) has been studied as a potential therapeutic option in cancer, namely in hepatocellular carcinoma. Previously, our research group evaluated the effect of human Amniotic Membrane Protein Extracts (hAMPE) in cancer therapy, demonstrating that hAMPE inhibit the metabolic activity of human hepatocellular carcinoma cell lines: Hep3B2.1-7, HepG2 and Huh7. Therefore, and considering the close relationship between metabolic activity and oxidative stress, the aim of this study was to evaluate the effect of hAMPE treatment in glucose metabolism and its role in oxidative stress of hepatocellular carcinoma. METHODS AND RESULTS: Glucose uptake and lactate production was assessed by 1 H-NMR, and the expression of several mediators of the glycolytic pathway was evaluated by Western blot or fluorescence. Total antioxidant capacity (TAC) and biomarkers of oxidative stress effects in proteins were detected. Our results showed that hAMPE treatment increased glucose consumption on Hep3B2.1-7, HepG2, and Huh7 through the increase of GLUT1 in Hep3B2.1-7 and Huh7, and GLUT3 in HepG2 cells. It was observed an increased expression of 6-phosphofrutokinase (PFK-1L) in all cell lines though glucose was not converted to lactate on HepG2 and Huh7 cells, suggesting that hAMPE treatment may counteract the Warburg effect observed in carcinogenesis. In Hep3B2.1-7, hAMPE treatment induced an increase in expression of lactate dehydrogenase (LDH) and monocarboxylate transporter isoform 4 (MCT4). We further detected that hAMPE enhances the TAC of culture media after 2 and 8 h. This was followed by a degree of protection against proteins nitration and carbonylation. CONCLUSIONS: Overall, this work highlights the potential usefulness of hAMPE as anticancer therapy through the modulation of the glycolytic and oxidative profile in human hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Âmnio/química , Âmnio/metabolismo , Biomarcadores/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Glucose/metabolismo , Glicólise , Humanos , Ácido Láctico/metabolismo , Neoplasias Hepáticas/metabolismo , Estresse Oxidativo
3.
Pharmaceutics ; 13(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34452127

RESUMO

The lyoprotective effects of mannitol and lactose have been evaluated in the production of sildenafil citrate liposomes. Liposomes were prepared by mixing the components under ultrasonic agitation, followed by a transmembrane pH gradient for remote drug loading. Mannitol and lactose, as compared to sucrose and trehalose, were used as the stabilizing agents, and different freeze-drying cycles were assayed. The remaining moisture and the thermal characteristics of the lyophilized samples were analyzed. Size, entrapment efficiency, biocompatibility, and cell internalization of original and rehydrated liposomes were compared. The type of additive did not affect the biocompatibility or cell internalization, but did influence other liposome attributes, including the thermal characteristics and the remaining moisture of the lyophilized samples. A cut-off of 5% (w/w) remaining moisture was an indicator of primary drying completion-information useful for scaling up and transfer from laboratory to large-scale production. Lactose increased the glass transition temperature to over 70 °C, producing lyoprotective effects similar to those obtained with sucrose. Based on these results, formulations containing liposomes lyophilized with lactose meet the FDA's requirements and can be used as a biocompatible and biodegradable vehicle for the pulmonary delivery of therapeutic doses of sildenafil citrate.

4.
Carbohydr Polym ; 254: 117303, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357870

RESUMO

Exopolysaccharides (EPS) produced by cyanobacteria are complex biomolecules of anionic nature with potential biomedical applications. In this study, the EPS produced by the Nostoc sp. strains PCC7936 and PCC7413 were characterized and evaluated as a biomaterial for new wound dressings. The addition of acetate ions to the culture medium slightly stimulated EPS production, achieving 1463.1 ± 16.0 mgL-1 (PCC7413) and 1372.1 ± 29.0 mgL-1 (PCC7936). Both EPS presented nine monosaccharide residues and a MW > 1000 kDa. The acetate addition changed the monosaccharide molar percentages. FTIR and DLS results confirmed the anionic nature and the presence of sulfate groups in both EPS, which are determinant features for biomedical applications. Both EPS at 1%(w/v) formed gels in the presence of 0.4%(w/v) FeCl3. Results obtained for MTT assay and wound healing in vitro scratch assay revealed hydrogels biocompatibility and ability to promote fibroblast migration and proliferation that was greater in PCC7936. The Nostoc EPS hydrogels presented promising properties to be applied in the treatment of skin injuries.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Monossacarídeos/química , Nostoc/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Cicatrização/efeitos dos fármacos , Acetatos/química , Bandagens , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cloretos/química , Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células HeLa , Ácidos Hexurônicos/química , Humanos , Peso Molecular , Polissacarídeos Bacterianos/isolamento & purificação
5.
Rev Bras Ortop (Sao Paulo) ; 55(4): 404-409, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32904813

RESUMO

Tibial plateau fractures are a risk to the functional integrity of the knee, affecting the axial alignment and capable of leading to pain and disability of the individual. Early weight bearing and joint mobilization can prevent these functional deficits. the goal of the present study was to conduct a systematic review of the literature about studies that quote the beginning, evolution, and progression criteria for weight-bearing in postoperative period of tibial plateau fractures. We selected articles published in the last 12 years, in Portuguese and English, that described the time of onset and progression of weight-bearing, considering the severity of the fracture. Thirty-six articles were selected. There is no consensus in the literature as to the beginning and evolution of weight-bearing in the postoperative period of tibial plateau fractures; however, a relationship between the severity of the fracture and the fixation method has been observed.

6.
Rev. bras. ortop ; 55(4): 404-409, Jul.-Aug. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1138059

RESUMO

Abstract Tibial plateau fractures are a risk to the functional integrity of the knee, affecting the axial alignment and capable of leading to pain and disability of the individual. Early weight bearing and joint mobilization can prevent these functional deficits. the goal of the present study was to conduct a systematic review of the literature about studies that quote the beginning, evolution, and progression criteria for weight-bearing in postoperative period of tibial plateau fractures. We selected articles published in the last 12 years, in Portuguese and English, that described the time of onset and progression of weight-bearing, considering the severity of the fracture. Thirty-six articles were selected. There is no consensus in the literature as to the beginning and evolution of weight-bearing in the postoperative period of tibial plateau fractures; however, a relationship between the severity of the fracture and the fixation method has been observed.


Resumo As fraturas do planalto tibial constituem risco à integridade funcional do joelho, afetando o alinhamento axial e podendo levar à dor e à incapacidade do indivíduo. O suporte de carga e a mobilização articular precoce podem prevenir esses déficits e acelerar o processo de reabilitação. O objetivo do presente trabalho foi realizar uma revisão da literatura sobre estudos que citam o início, evolução e critérios de progressão do suporte de carga no pós-operatório das fraturas de planalto tibial. Foram selecionados artigos publicados nos últimos 12 anos, nos idiomas português e inglês, que descrevessem o tempo de início e progressão do suporte de carga, considerando a gravidade da fratura. Foram selecionados 36 artigos na literatura. Não há consenso na literatura quanto ao início e evolução do suporte de carga no pós-operatório das fraturas do planalto tibial. Contudo, observa-se relação entre a gravidade da fratura e o tempo de início da carga.


Assuntos
Dor , Reabilitação , Fraturas da Tíbia , Modalidades de Fisioterapia , Suporte de Carga , Fraturas Ósseas
7.
Sci Rep ; 10(1): 1739, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015384

RESUMO

Community structure of many systems changes across space in many different ways (e.g., gradual, random or clumpiness). Accessing patterns of species spatial variation in ecosystems characterized by strong environmental gradients, such as estuaries, is essential to provide information on how species respond to them and for identification of potential underlying mechanisms. We investigated how environmental filters (i.e., strong environmental gradients that can include or exclude species in local communities), spatial predictors (i.e., geographical distance between communities) and temporal variations (e.g., different sampling periods) influence benthic macroinfaunal metacommunity structure along salinity gradients in tropical estuaries. We expected environmental filters to explain the highest proportion of total variation due to strong salinity and sediment gradients, and the main structure indicating species displaying individualistic response that yield a continuum of gradually changing composition (i.e., Gleasonian structure). First we identified benthic community structures in three estuaries at Todos os Santos Bay in Bahia, Brazil. Then we used variation partitioning to quantify the influences of environmental, spatial and temporal predictors on the structures identified. More frequently, the benthic metacommunity fitted a quasi-nested pattern with total variation explained by the shared influence of environmental and spatial predictors, probably because of ecological gradients (i.e., salinity decreases from sea to river). Estuarine benthic assemblages were quasi-nested likely for two reasons: first, nested subsets are common in communities subjected to disturbances such as one of our estuarine systems; second, because most of the estuarine species were of marine origin, and consequently sites closer to the sea would be richer while those more distant from the sea would be poorer subsets.

8.
Polymers (Basel) ; 12(1)2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31947937

RESUMO

Hydrogels are considered to be the most ideal materials for the production of wound dressings since they display a three-dimensional structure that mimics the native extracellular matrix of skin as well as a high-water content, which confers a moist environment at the wound site. Until now, different polymers have been used, alone or blended, for the production of hydrogels aimed for this biomedical application. From the best of our knowledge, the application of a xanthan gum-konjac glucomannan blend has not been used for the production of wound dressings. Herein, a thermo-reversible hydrogel composed of xanthan gum-konjac glucomannan (at different concentrations (1% and 2% w/v) and ratios (50/50 and 60/40)) was produced and characterized. The obtained data emphasize the excellent physicochemical and biological properties of the produced hydrogels, which are suitable for their future application as wound dressings.

9.
Environ Sci Pollut Res Int ; 26(24): 24850-24862, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240644

RESUMO

Bisphenol-A is widely used chemical in industry and unfortunately often detected in natural waters. Considered as an emerging pollutant, bisphenol-A represents an environmental problem due to its endocrine-disrupting behavior. The production of activated carbon from alternative precursors has shown to be attractive in the removal of emerging pollutants from the water. Activated carbon was produced from waste coffee by physical and chemical activation and applied in the removal of bisphenol-A. The samples were characterized by elemental analysis, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and analysis of textural properties. Bisphenol-A adsorption experiments showed that the chemically activated carbon was more efficient due to its high specific surface area (1039 m2/g) compared to the physically activated carbon (4.0 m2/g). The bisphenol-A adsorption data followed the pseudo-second-order model and Langmuir isotherm, which indicated a maximum adsorption capacity of 123.22 mg/g for chemically activated carbon. The results demonstrated a potential use of the coffee grounds as a sustainable raw material for the production of chemically activated carbon that could be used in water treatment.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Carvão Vegetal/química , Café , Fenóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Compostos Benzidrílicos/química , Cloretos/química , Cinética , Microscopia Eletrônica de Varredura , Fenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Difração de Raios X , Compostos de Zinco/química
10.
Environ Int ; 127: 462-472, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30978481

RESUMO

Organophosphate flame retardants (PFRs) have largely replaced the market of polybrominated diphenyl ethers (PBDEs). Concerns about PFR contamination and its impact on human health have consequently increased. A comprehensive investigation on the human exposure pathways to PFRs is to be endeavoured. This study investigated the occurrence of PFR metabolites in human urine, serum and hair, correlating them with external exposure data that was presented in our previous studies. Participants from Oslo (n = 61) provided a set of samples, including dust, air, handwipes, food, urine, serum and hair. Associations between PFR metabolites analyzed in the biological samples and the PFRs in environmental samples were explored. Different sampling strategies for dosimeters (e.g. floor/surface dust, personal/stationary air) were also compared to understand which is better for predicting human exposure to PFRs. Seven out of the eleven target PFR metabolites, including diphenyl phosphate (DPHP) and bis(1-chloro-2-propyl)-1-hydroxy-2-propyl phosphate (BCIPHIPP), were frequently detected (DF > 30%) in urine. DPHP was the most frequently detected metabolite in both serum and hair. Several PFR metabolites had higher levels in morning urine than in afternoon urine. Floor dust appeared to be a better proxy for estimating PFR internal exposure than surface dust, air, and handwipes. Some PFRs in handwipes and air were also correlated with their metabolites in urine and hair. Age, beverage consumption and food consumption were negatively associated with DPHP levels in urine. Discrepancies observed between the external and internal exposure for some PFRs call for further investigation on PFR bioaccessibility and clearance.


Assuntos
Retardadores de Chama/análise , Organofosfatos/análise , Monitoramento Ambiental , Humanos
11.
Int J Dermatol ; 58(4): 483-490, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30697687

RESUMO

BACKGROUND: Fishing is an important economic activity worldwide, but there are only a few studies on the skin health of fishermen. Daily activities in fishing communities expose fishermen to risks of traumatic, actinic, and sea dermatoses. METHODS: A semi-structured questionnaire was applied to 388 fishermen from 2014 to 2015 at their workplace (Z-8 to Z-13 fishing communities). The data collected were evaluated for descriptive analysis. In the bivariate analysis of the data, the Pearson chi-square test was used. The multinomial logistic regression was used to obtain estimates of odds ratios and adjusted confidence intervals for confounding variables. RESULTS: Three hundred and nine (79.6%) fishermen reported accidents during their fishing activity. The main fish species implicated were Genidens genidens and Scorpaena brasiliensis. Inappropriate or potentially harmful traditional treatments without scientific evidence of efficacy were recorded as main/auxiliary treatment. Other significant skin injuries were due to trauma from fishing tackle and exposure to ultraviolet radiation. Three hundred and twenty (82.5%) fishermen reported that they had never used any sun protective devices or sunscreen. CONCLUSIONS: Traumatic injuries due to fish stings were the most common accidents in this group. Despite chronic occupational sun exposure and its hazards, most fishermen did not adopt any method of photoprotection. Health educational activities as well as a specific health program for these professionals are necessary to improve the health of fishermen in Guanabara Bay area.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Mordeduras e Picadas/epidemiologia , Peixes , Abastecimento de Alimentos , Exposição Ocupacional , Pele/lesões , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil , Feminino , Abastecimento de Alimentos/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Roupa de Proteção/estatística & dados numéricos , Protetores Solares/uso terapêutico , Inquéritos e Questionários , Fatores de Tempo , Raios Ultravioleta/efeitos adversos , Adulto Jovem
12.
Chemosphere ; 212: 1047-1057, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30286534

RESUMO

The aim of the present study was to investigate the in vitro metabolism of two emerging organophosphate flame retardants, namely tetrekis(2-chlorethyl)dichloroisopentyldiphosphate (V6) and bisphenol-A bis-diphenyl phosphate (BDP) in human liver microsomes (HLMs), HLM S9 fractions and in human serum. In particular, the role of cytochrome P450 (CYPs) enzymes and/or paraoxonases (PONs) in the formation of V6 and BDP phase I metabolites was studied. Mono-, di-hydroxylated and hydrolytic phase I metabolites of V6 were mainly formed by CYPs in HLMs, while hydrolytic and O-dealkylated phase I metabolites of BDP were generated by PONs mainly in serum experiments. Limited number of glucuronidated and sulfated phase II metabolites were also identified for the two chemicals. The activity of seven recombinant CYPs (rCYPs) including rCYP1A2, rCYP2B6, rCYP2C9, rCYP2C19, rCYP2D6, rCYP2E1 and rCYP3A4 in the in vitro phase I metabolism of V6 and BDP was investigated. The formation of V6 metabolites was catalyzed by several enzymes, especially rCYP1A2 that was responsible for the exclusive formation of two metabolites, one primary (M1) and its secondary metabolite (M9). For BDP, only one phase I metabolite (MM1) was catalyzed by the seven rCYPs. Collectively, these results indicate that CYPs have a predominant role in the metabolism of V6, while PONs have a predominant role in BDP in vitro metabolism. These results are a starting point for future studies involving the study of the toxicity, bioaccumulation and in vivo biomonitoring of V6 and BDP.


Assuntos
Retardadores de Chama/análise , Microssomos Hepáticos/metabolismo , Arildialquilfosfatase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Retardadores de Chama/toxicidade , Humanos , Espectrometria de Massas/métodos , Organofosfatos/metabolismo , Organofosfatos/toxicidade
20.
Appl Opt ; 56(31): 8811-8815, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29091696

RESUMO

An innovative and effective architecture for lidar systems is presented and experimentally demonstrated. The proposed scheme can also be easily exploited for optical communications. In particular, the system includes an innovative lidar software-defined architecture based on optically coherent detection, overcoming current drawbacks of time of flight incoherent systems. The experiments demonstrate the ability to perform long range detection resorting to the waveform compression on the continuous wave approach, obtaining a range resolution of 15 cm with a sensitivity of -95 dBm. Beside the bulk implementation, the system has been also implemented in a photonic integrated circuit using complementary metal-oxide-semiconductor-compatible silicon on insulator technology with an extremely reduced footprint of 1.5 mm×3.5 mm. The testing of the integrated device confirms the effectiveness of this proof-of-concept realization.

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