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1.
Cell Mol Neurobiol ; 43(2): 433-454, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35107689

RESUMO

Unlike the central nervous system, the peripheral one has the ability to regenerate itself after injury; however, this natural regeneration process is not always successful. In fact, even with some treatments, the prognosis is poor, and patients consequently suffer with the functional loss caused by injured nerves, generating several impacts on their quality of life. In the present review we aimed to address two strategies that may considerably potentiate peripheral nerve regeneration: stem cells and tissue engineering. In vitro studies have shown that pluripotent cells associated with neural scaffolds elaborated by tissue engineering can increase functional recovery, revascularization, remyelination, neurotrophin expression and reduce muscle atrophy. Although these results are very promising, it is important to note that there are some barriers to be circumvented: the host's immune response, the oncogenic properties attributed to stem cells and the duration of the pro-regenerative effects. After all, more studies are still needed to overcome the limitations of these treatments; those that address techniques for manipulating the lesion microenvironment combining different therapies seem to be the most promising and proactive ones.


Assuntos
Traumatismos dos Nervos Periféricos , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Qualidade de Vida , Nervos Periféricos/fisiologia , Regeneração Nervosa/fisiologia , Células-Tronco , Traumatismos dos Nervos Periféricos/terapia
2.
Chemosphere ; 289: 133222, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34902391

RESUMO

Every year, a considerable volume of medications is consumed. Because these medications are not entirely eliminated in the sewage treatment plants and impact the surface waterways, the environmental pollution problem arises. This study objective was to evaluate the possibility of using an absorbent material made with of polyethylene terephthalate and sugarcane bagasse ash functionalized with iron oxide (PETSCA/Fe3+) in the removal of naproxen from water. The feasibility of having viable features in becoming an efficient adsorbent was first determined. The batch test was performed, allowing the dose effect, adsorption kinetics, and isotherm models to be evaluated. The determination of naproxen (NAP) concentration in water was analyzed on a high-performance liquid chromatograph and Langmuir method best represented the adsorption isotherm model. PETSCA/Fe3+ adsorbent material demonstrated potential in the naproxen removal at a low cost. The batching process was satisfactory, with 0.30 g of composite being the optimum fit for the system. The adsorption kinetics was determined and described by the pseudo second order model, with an average correlation coefficient (R2) of 0.974. The adsorption system model was best represented by the Langmuir isotherm curve. Moreover, adsorption in the presence of H2O2 had a positive impact on the process, removing 81.9% of NAP, whereas the process without H2O2 did not remove more than 62.0% of NAP. Therefore, because of its good qualities for NAP removal, PETSCA/Fe3+ is recommended as adsorbent material, primarily in small-volume water filtration systems.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Compostos Férricos , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Naproxeno , Água , Poluentes Químicos da Água/análise
3.
Life Sci ; 279: 119667, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087280

RESUMO

Estimates indicate that cancer will become the leading cause of mortality worldwide in the future. Tumorigenesis is a complex process that involves self-sufficiency in signs of growth, insensitivity to anti-growth signals, prevention of apoptosis, unlimited replication, sustained angiogenesis, tissue invasion, and metastasis. Cancer stem cells (CSCs) have an important role in tumor development and resistance. Here we will approach phenotypic plasticity capacity, highly efficient DNA repair systems, anti-apoptotic machinery, sustained stemness features, interaction with the tumor microenvironment, and Notch, Wnt, and Hedgehog signaling pathways. The researches about CSCs as a target in cancer treatment has been growing. Many different options have pointed beneficial results, such as pathways and CSC-surface markers targeting. Besides its limitations, nanotherapeutics have emerged as a potential strategy in this context since they aim to improve pharmacokinetics, biodistribution, and reduce the side effects observed in traditional treatments. Nanoparticles have been studied in this field, mostly for drug delivery and a multitherapy approach. Another widely researched approaches in this area are related to heat therapy, such as photothermal therapy, photodynamic therapy and magnetic hyperthermia, besides molecular targeting. This review will contemplate the most relevant studies that have shown the effects of nanotherapeutics. In conclusion, although the studies analyzed are mostly preclinical, we believe that there is strong evidence that nanoparticles can increase the chances of a better prognosis to cancer in the future. It is also essential to transpose these findings to the clinic to confirm and better understand the role of nanotherapeutics in this context.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Antineoplásicos/química , Humanos , Nanopartículas/química , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia
4.
Eng. sanit. ambient ; 22(3): 429-435, mai.-jun. 2017. tab, graf
Artigo em Português | LILACS | ID: biblio-840420

RESUMO

RESUMO Os objetivos deste trabalho foram avaliar a presença e a concentração dos anti-inflamatórios diclofenaco e naproxeno em um córrego urbano localizado no município de Três de Lagoas, Mato Grosso do Sul, que recebe efluente de uma estação de tratamento de esgoto; e verificar a influência da temperatura da água na ocorrência dos fármacos em águas superficiais. Foi realizado monitoramento dos anti-inflamatórios e dos parâmetros temperatura, pH e oxigênio dissolvido na água durante 12 meses consecutivos (outubro de 2008 a setembro de 2009). Foram coletadas amostras de água mensalmente em seis pontos, representando diferentes seções do córrego. As amostras foram submetidas ao processo de extração em fase sólida e analisadas por cromatografia líquida de alta eficiência. Para verificar a influência da temperatura da água na ocorrência dos anti-inflamatórios diclofenaco e naproxeno nos ambientes aquáticos, utilizou-se um modelo de regressão logística do Statistical Analysis System versão 9.0. Os anti-inflamatórios diclofenaco e naproxeno foram detectados nos diferentes pontos monitorados no Córrego da Onça. Os demais parâmetros avaliados neste estudo foram comparados com os padrões de qualidade de água estabelecidos pela Resolução CONAMA nº 357/2005. A maior concentração do diclofenaco foi detectada no ponto localizado à jusante da estação de tratamento de esgoto do município, enquanto a maior concentração de naproxeno foi registrada na foz do córrego. A temperatura da água influencia de forma inversamente proporcional a ocorrência dos dois anti-inflamatórios no córrego, ou seja, quanto maior a temperatura do corpo hídrico, menor a probabilidade de detecção dos fármacos diclofenaco e naproxeno.


ABSTRACT The aims of this study were to evaluate the presence and concentration of the anti-inflammatory drugs diclofenac and naproxen in an urban stream located in Três Lagoas, Mato Grosso do Sul, Brazil, that receives effluent from a wastewater treatment plant; and to evaluate the influence of water temperature in the occurrence of these drugs into surface waters. Monitoring of both anti-inflammatory and the parameters temperature, pH and dissolved oxygen was held in this water body during 12 consecutive months (October 2008 to September 2009). Water samples were collected monthly at six points representing different sections of the stream. The samples were subjected to solid phase extraction procedure and analyzed by high performance liquid chromatography. To check the influence of water temperature on the occurrence of the anti-inflammatory drugs diclofenac and naproxen in aquatic environments, it was used a logistic model of regression, the Statistical Analysis System version 9.0. The anti-inflammatory drugs diclofenac and naproxen were detected at different points in the Stream of Onça. The other parameters evaluated in this study were compared with the water quality standards established by the CONAMA Resolution 357/2005. The highest concentration of diclofenac was detected in the point located downstream of the wastewater treatment plant of the city, while the largest concentration of naproxen was recorded at the mouth of the stream. The water temperature influence, in an inversely proportional way, the occurrence of both anti-inflammatory in the stream, the higher the temperature the lower the water body probability of detection of drug diclofenac and naproxen.

5.
Environ Monit Assess ; 187(6): 379, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26013657

RESUMO

The growing use of pharmaceutical drug is mainly due to several diseases in human and in animal husbandry. As these drugs are discharged into waterways via wastewater, they cause a major impact on the environment. Many of these drugs are hormones; in which even at low concentrations can alter metabolic and physiological functions in many organisms. Hormones were found in surface water, groundwater, soil, and sediment at concentrations from nanograms to milligrams per liter of volume--quantities known to cause changes in the endocrine system of aquatic organisms. This study aimed to develop a methodology for hormone detection (estriol, estrone, 17ß-estradiol, 17α-ethinylestradiol, progesterone, and testosterone) on surface and treated water samples. Sample toxicity was assessed by ecotoxicology tests using Daphnia magna. A liquid chromatograph coupled to a mass spectrometer with an electrospray ionization source (LC-ESI-MS/MS) was used for the analysis. The results showed that samples were contaminated by the hormones estriol, estrone, progesterone, 17ß-estradiol, and 17α-ethinylestradiol during the sampling period, and the highest concentrations measured were 90, 28, 26, 137, and 194 ng · L(-1), respectively. This indicates the inflow of sewage containing these hormones at some points in the Piracicaba River in the State of Sao Paulo-Brazil. Results indicated little toxicity of the hormone estriol in D. magna, indicating that chronic studies with this microcrustacean are necessary.


Assuntos
Água Potável/análise , Disruptores Endócrinos/análise , Hormônios Esteroides Gonadais/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Brasil , Cromatografia Líquida , Daphnia , Ecotoxicologia , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental/métodos , Estradiol/análise , Estrona/análise , Etinilestradiol/análise , Hormônios Esteroides Gonadais/toxicidade , Humanos , Esgotos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade , Abastecimento de Água
6.
Braz. arch. biol. technol ; 53(5): 1245-1254, Sept.-Oct. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-564103

RESUMO

In this present work, three strains of Pleurotus and Trichoderma reesei were cultivated in media with pre-treated bagasse and vinasse. Cellulolytic and lignolytic activities and biomass production were analyzed. The treatment of the bagasse with 2 percent H2O2 + 1.5 percent NaOH + autoclave resulted in a greater fiber breakage increasing the cellulose level up to 1.2 times and decreasing 8.5 times the hemicellulose content. This treatment also resulted in a high lignolytic activity for all cultures utilized. T. reesei produced laccase, peroxidase and manganese-peroxidase in all the treatments, having its manganese-peroxidase activity raging from 1.9 to 4.8 times higher than the basidiomycetes.


Recentemente o uso de material lignocelulolítico tem mostrado um importante avanço na produção de biocombustíveis. O bagaço e a vinhaça são resíduos oriundos do processamento da cana de açúcar e contem um alto teor de carbono, que geralmente é usado na co-geração de energia e ração animal. Três linhagens de Pleurotus e um ascomiceto, Trichoderma reesei, foram cultivados em bagaço pré-tratado e vinhaça. As atividades lignolíticas e celulolíticas foram analisadas, tanto quanto a produção de biomassa. Foi observado que o tratamento no bagaço com 2 por cento H2O2 + 1.5 por cento NaOH + autoclave resultou numa maior quebra da fibra, aumentando o teor de celulose em 1.2 vezes mais e diminuiu em 8.5 vezes o conteúdo de hemicelulose. Este tratamento também resultou numa alta atividade lignolítica pelos fungos utilizados. O ascomiceto T. reesei produziu lacase, peroxidase e manganês-peroxidase em todos os tratamentos, tendo uma atividade de manganês-peroxidase variando entre 1.9 a 4.8 vezes mais que nos basidiomicetos.

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