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1.
Proc Biol Sci ; 290(2004): 20230543, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37528708

RESUMO

Medusozoa (Cnidaria) are characterized by diverse life cycles, with different semaphoronts (medusa, medusoid, fixed gonophore, polyp) representing the sexual phase and carrying the gametes. Although egg size is often considered a proxy to understand reproductive and developmental traits of medusozoans, understanding of the processes influencing egg size variation in the group under an evolutionary context is still limited. We carried out a comprehensive review of the variation of egg size in Medusozoa to test whether this variation is related to biological/sexual or environmental traits. Egg size presents a strong phylogenetic signal (λ = 0.79, K = 0.67), explaining why closely related species with different reproductive strategies and different individual sizes have similar egg sizes. However, variation in egg size is influenced by the number of eggs, depth and temperature, with larger eggs frequently present in species with few eggs (1-15), in deep-sea species and in cold-water species. Conversely, the production of small eggs among cold-water species of Staurozoa might be associated with the development of a small benthic larvae in this group. Our study reinforces that egg sizes respond to reproductive and environmental traits, although egg size is highly conserved within medusa classes.


Assuntos
Cnidários , Animais , Filogenia , Reprodução , Evolução Biológica , Água
2.
Int J Biol Macromol ; 261(Pt 1): 129049, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38176510

RESUMO

The economic burden of chronic wounds, the complexity of the process of tissue repair and the possibility of resistant bacterial infections, have triggered a significant research interest in the application of natural alternative therapies for wound healing. Biomolecules are intrinsically multi-active, as they affect multiple mechanisms involved in tissue repair phenomenon, including immunomodulatory, anti-inflammatory, cell proliferation, extra cellular matrix remodeling and angiogenesis. Chitosan features a unique combination of attributes, including intrinsic hemostatic, antimicrobial, and immunomodulatory properties, that make it an exceptional candidate for wound management, in the development of wound dressings and scaffolds. In this study, we produced nanoemulsions (NE) loaded with SFO, characterized them, and evaluated their tissue repairing properties. Dynamic light scattering (DLS) analysis confirmed the formation of a nanoemulsion with a droplet size of 21.12 ± 2.31 nm and a polydispersity index (PdI) of 0.159, indicating good stability for up to 90 days. To investigate the potential wound healing effects, SFO-loaded NE were applied on male C57BL/6 mice for seven consecutive days, producing a significantly higher wound closure efficiency (p < 0.05) for the group treated with SFO-loaded NE compared to the control group treated with the saline solution. This finding indicates that the SFO-loaded NE exhibits therapeutic properties that effectively promote wound healing in this experimental model. Then, SFO-loaded NE were incorporated into chitosan:polyvinyl alcohol (PVA)-based films. The inclusion of NE into the polymer matrix resulted in increased lipophilicity reflected by the contact angle results, while decreasing moisture absorption, water solubility, and crystallinity. Moreover, FTIR analysis confirmed the formation of new bonds between SFO-NE and the film matrix, which also impacted on porosity properties. Thermal analysis indicated a decrease in the glass transition temperature of the films due to the presence of SFO-NE, suggesting a plasticizing role of NE, confirmed by XRD results, that showed a decrease in the crystallinity of the blend films upon the addition of SFO-NE. AFM images showed no evidence of NE droplet aggregation in the Chitosan:PVA film matrix. Moisture absorption and water content decreased upon incorporation of SFO-loaded NE. Although the inclusion of NE increased hydrophobicity and water contact angle, the values remained within an acceptable range for wound healing applications. Overall, our results emphasize the significant tissue repairing properties of SFO-loaded NE and the potential of Chitosan:PVA films containing nanoencapsulated SFO as effective formulations for wound healing with notable tissue repairing properties.


Assuntos
Quitosana , Óleos Voláteis , Humanos , Camundongos , Animais , Masculino , Quitosana/química , Óleos Voláteis/farmacologia , Camundongos Endogâmicos C57BL , Cicatrização , Água/farmacologia , Álcool de Polivinil/química , Antibacterianos/farmacologia
3.
Lung Cancer ; 108: 96-102, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28625657

RESUMO

OBJECTIVES: EGFR tyrosine kinase inhibitors (TKIs) are widely used to treat NSCLC, primarily patients with activating mutations, with more limited response in wild-type disease. However, even with EGFR-mutated disease, many patients fail to respond, most who initially respond fail to respond completely, and almost all develop resistance and inevitably progress. New therapeutic options that improve these outcomes could provide substantial clinical benefit. We previously demonstrated strong synergistic effects between erlotinib and the tumor suppressor microRNA miR-34a, sensitizing NSCLC cells with primary resistance (EGFR wild-type) and restoring sensitivity in cells with acquired resistance. Here, we report results of further research combining miR-34a with newer generation EGFR-TKIs in similar experiments. MATERIALS AND METHODS: Human NSCLC cell lines with varying degrees of primary and acquired resistance to erlotinib were assessed for sensitivity to a broad set of combined doses of miR-34a mimic and afatinib, rociletinib or osimertinib. Multiple analytical approaches were used to characterize effects on cancer cell proliferation as additive, antagonistic or synergistic. RESULTS: Mimics of miR-34a synergized with afatinib, rociletinib or osimertinib in all EFGR-mutant cells tested. Best and consistently strong synergy was observed in cell models with acquired resistance. Synergy was also evident in most EGFR wild-type cells with miR-34a combined with rociletinib and osimertinib, but not with afatinib. The effects were observed across a broad range of dose levels and drug ratios, with maximal synergy at doses yielding high levels of inhibition beyond those possible to be induced by the single agents alone. CONCLUSION: Combined miR-34a and EGFR-TKIs synergistically sensitize both EGFR wild-type and mutant NSCLC cells, supporting clinical investigation of these combinations as a strategy to overcome both primary and acquired resistance to EGFR-TKIs in NSCLC, possibly with an improved therapeutic index.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , Inibidores de Proteínas Quinases/farmacologia , Alelos , Substituição de Aminoácidos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib/farmacologia , Humanos , Mutação
4.
Agora USB ; 18(2): 414-425, jul.-dic. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-989224

RESUMO

Resumen Los museos virtuales propician el aprendizaje activo y en el tema del patrimonio, captan el interés del visitante favoreciendo su acercamiento a la información y el conocimiento, gracias a los recursos y formatos multimedia. También se evidenció que las nuevas generaciones, privilegian los gráficos sobre los textos escritos, lo cual lleva a priorizar el rol de los recursos multimedia en estos entornos.


Abstract The virtual museums foster active learning and in the subject of heritage, they capture the interest of the visitor favoring his approach to information and knowledge, thanks to the resources and multimedia formats. It was also evident that the new generations privilege the use of graphics over written texts, which leads to prioritize the role of multimedia resources in these environments.

5.
Chemosphere ; 78(1): 61-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19853883

RESUMO

Hydrogen Peroxide Plus (HPP) is a newly developed, stabilized-H(2)O(2)-based compound. This study was aimed at determining the disinfection efficiency of HPP in greywater (GW), assessing HPP dose requirements and evaluating the feasibility of its use in small-scale GW-treatment systems. Fecal coliforms were the most sensitive to treatment, followed by somatic coliphages and F+ bacteriophages. The calculated HPP dose required to reduce fecal coliform counts by 99% was 125mg H(2)O(2)L(-1), with a contact time of 35min. The use of HPP was found feasible and comparable to the use of chlorine for small systems with a flow rate of 5m(3)d(-1). HPP is suggested as an alternative for GW disinfection in small communities and private houses.


Assuntos
Anti-Infecciosos/farmacologia , Desinfecção , Peróxido de Hidrogênio/farmacologia , Poluentes da Água/isolamento & purificação , Anti-Infecciosos/química , Bacteriófagos/efeitos dos fármacos , Colífagos/efeitos dos fármacos , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos , Microbiologia da Água , Purificação da Água
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