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1.
Gels ; 9(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37754381

RESUMO

Sustained release is highly desired for "efficacious, safe and convenient" drug delivery, particularly for those anticancer drug molecules with toxicity. In this study, a modified coaxial electrospraying process was developed to coat a hydrophobic lipid, i.e., stearic acid (SA), on composites composed of the anticancer drug tamoxifen citrate (TC) and insoluble polymeric matrix ethylcellulose (EC). Compared with the electrosprayed TC-EC composite microparticles M1, the electrosprayed SA-coated hybrid microparticles M2 were able to provide an improved TC sustained-release profile. The 30% and 90% loaded drug sustained-release time periods were extended to 3.21 h and 19.43 h for M2, respectively, which were significantly longer than those provided by M1 (0.88 h and 9.98 h, respectively). The morphology, inner structure, physical state, and compatibility of the components of the particles M1 and M2 were disclosed through SEM, TEM, XRD, and FTIR. Based on the analyses, the drug sustained-release mechanism of multiple factors co-acting for microparticles M2 is suggested, which include the reasonable selections and organizations of lipid and polymeric excipient, the blank SA shell drug loading, the regularly round shape, and also the high density. The reported protocols pioneered a brand-new manner for developing sustained drug delivery hybrids through a combination of insoluble cellulose gels and lipid using modified coaxial electrospraying.

2.
Psychol Res Behav Manag ; 16: 3607-3621, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693329

RESUMO

Purpose: Drawing from the sociocultural-self model, this study aims to examine the influence of self-affirmation on the academic outcomes of lower-class migrant students, as well as the psychological mechanism underlying this phenomenon. Patients and Methods: A field experiment was conducted at a comprehensive secondary school in the southern region of China. Our study sample comprised 1534 immigrant students from diverse regions across the country, with an average proportion of 59.6% of students registered with a rural hukou. The hukou system plays a pivotal role in measuring social class in China, thus it was used as a proxy for lower and higher social class, with rural hukou students considered to be lower-class and urban hukou students considered to be higher-class. Prior to the English test, students in the self-affirmed group were engaged in a brief writing exercise that focused on their core values, whereas the control group wrote about a neutral topic. Results: The primary outcome of interest was the effect of self-affirmation on English test scores, whereas the secondary outcome was the students' survey stereotype threat. The results exhibit that self-affirmation more significantly improved the English test performance of lower-class students compared to higher-class students, and this positive effect was mediated by reducing stereotype threat. Conclusion: Our findings unravel the impact of self-affirmation on the academic performance of migrant students from different social classes and signify the mediating role of stereotype threat in this process. The present study extends previous findings to students from immigrant families in the Chinese cultural context, and these findings demonstrate that self-affirmation can constitute a promising intervention for stereotype threat and achievement gaps due to social class differences in immigrant family groups. Considering that this intervention takes only about 15 minutes of time, entails almost zero cost, does no harm, and that it focuses on disadvantaged immigrant students, it may provide valuable insights for educational policies to be implemented in a new type of migrant city such as Shenzhen.

3.
Front Bioeng Biotechnol ; 11: 1112338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741747

RESUMO

The poor solubility of numerous drugs pose a long-existing challenge to the researchers in the fields of pharmaceutics, bioengineering and biotechnology. Many "top-down" and "bottom-up" nano fabrication methods have been exploited to provide solutions for this issue. In this study, a combination strategy of top-down process (electrospinning) and bottom-up (self-emulsifying) was demonstrated to be useful for enhancing the dissolution of a typical poorly water-soluble anticancer model drug (paclitaxel, PTX). With polyvinylpyrrolidone (PVP K90) as the filament-forming matrix and drug carrier, polyoxyethylene castor oil (PCO) as emulsifier, and triglyceride (TG) as oil phase, Both a single-fluid blending process and a coaxial process were utilized to prepare medicated nanofibers. Scanning electron microscope and transmission electron microscope (TEM) results clearly demonstrated the morphology and inner structures of the nanofibers. The lipid nanoparticles of emulsions after self-emulsification were also assessed through TEM. The encapsulation efficiency (EE) and in vitro dissolution tests demonstrated that the cores-shell nanofibers could provide a better self-emulsifying process int terms of a higher EE and a better drug sustained release profile. Meanwhile, an increase of sheath fluid rate could benefit an even better results, suggesting a clear process-property-performance relationship. The protocols reported here pave anew way for effective oral delivery of poorly water-soluble drug.

4.
Biomolecules ; 13(1)2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36671570

RESUMO

Herbal medicine has a long history of medical efficacy with low toxicity, side effects and good biocompatibility. However, the bioavailability of the extract of raw herbs and bioactive compounds is poor because of their low water solubility. In order to overcome the solubility issues, electrospinning technology can offer a delivery alternative to resolve them. The electrospun fibers have the advantages of high specific surface area, high porosity, excellent mechanical strength and flexible structures. At the same time, various natural and synthetic polymer-bound fibers can mimic extracellular matrix applications in different medical fields. In this paper, the development of electrospinning technology and polymers used for incorporating herbal medicine into electrospun nanofibers are reviewed. Finally, the recent progress of the applications of these herbal medicine nanofibers in biomedical (drug delivery, wound dressing, tissue engineering) and food fields along with their future prospects is discussed.


Assuntos
Nanofibras , Nanofibras/química , Engenharia Tecidual , Preparações Farmacêuticas , Polímeros/química , Extratos Vegetais
5.
Front Immunol ; 13: 974310, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091048

RESUMO

Mammalian single immunoglobulin (Ig) interleukin-1 receptor related molecule (SIGIRR), an important member of the Toll/interleukin-1 receptor (TIR) family, plays important balancing roles in the inflammatory responses. In the present study, the double Ig interleukin-1 receptor related molecule (DIGIRR), the homologous of SIGIRR, was characterized in golden pompano (Trachinotus ovatus) (termed as trDIGIRR). The full-length cDNA of trDIGIRR was 2,167 bp with an open reading frame (ORF) of 1,572 bp encoding 523 amino acids. The trDIGIRR contained several conserved domains including a signal peptide, two Ig domains, a transmembrane domain and a TIR domain, and shared high sequence identities with its teleost counterparts. Realtime qPCR analysis revealed that the trDIGIRR was distributed in all tissues examined, with high expressions in intestine, liver and head kidney. The expressions of trDIGIRR were induced by Vibrio alginolyticus, lipopolysaccharide (LPS) and polyinosinic-polycytidylic acid (poly I:C) challenge. Further analysis revealed that trDIGIRR was mainly located in the cytoplasm. In addition, the co-immunoprecipitation (co-IP) assay identified that trDIGIRR could interact with myeloid differentiation factor 88 (MyD88), but not interact with TIR domain containing adaptor protein inducing interferon-ß (TRIF). Our results provide basis for studying the immune role of fish DIGIRR.


Assuntos
Proteínas de Peixes , Receptores de Interleucina-1 , Animais , Proteínas de Peixes/metabolismo , Peixes , Imunoglobulina G/genética , Mamíferos , Filogenia , Poli I-C/farmacologia , Receptores de Interleucina-1/genética
6.
Biomolecules ; 12(6)2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35740919

RESUMO

The timely and effective control and repair of wound bleeding is a key research issue all over the world. From traditional compression hemostasis to a variety of new hemostatic methods, people have a more comprehensive understanding of the hemostatic mechanism and the structure and function of different types of wound dressings. Electrospun nanofibers stand out with nano size, high specific surface area, higher porosity, and a variety of complex structures. They are high-quality materials that can effectively promote wound hemostasis and wound healing because they can imitate the structural characteristics of the skin extracellular matrix (ECM) and support cell adhesion and angiogenesis. At the same time, combined with amino acid polymers with good biocompatibility not only has high compatibility with the human body but can also be combined with a variety of drugs to further improve the effect of wound hemostatic dressing. This paper summarizes the application of different amino acid electrospun wound dressings, analyzes the characteristics of different materials in preparation and application, and looks forward to the development of directions of poly(amino acid) electrospun dressings in hemostasis.


Assuntos
Hemostáticos , Nanofibras , Aminoácidos/farmacologia , Hemostasia , Hemostáticos/farmacologia , Humanos , Nanofibras/química , Cicatrização
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