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To synthesize an effective and versatile nano-platform serving as a promising carrier for controlled drug delivery, visible-light-induced diselenide-crosslinked polyurethane micelles were designed and prepared for ROS-triggered on-demand doxorubicin (DOX) release. A rationally designed amphiphilic block copolymer, poly(ethylene glycol)-b-poly(diselenolane diol-co-isophorone diisocyanate)-b-poly(ethylene glycol) (PEG-b-PUSe-b-PEG), which incorporates dangling diselenolane groups within the hydrophobic PU segments, was initially synthesized through the polycondensation reaction. In aqueous media, this type of amphiphilic block copolymer can self-assemble into micellar aggregates and encapsulate DOX within the micellar core, forming DOX-loaded micelles that are subsequently in situ core-crosslinked by diselenides via a visible-light-triggered metathesis reaction of Se-Se bonds. Compared with the non-crosslinked micelles (NCLMs), the as-prepared diselenide-crosslinked micelles (CLMs) exhibited a smaller particle size and improved colloidal stability. In vitro release studies have demonstrated suppressed drug release behavior for CLMs in physiological conditions, as compared to the NCLMs, whereas a burst release of DOX occurred upon exposure to an oxidation environment. Moreover, MTT assay results have revealed that the crosslinked polyurethane micelles displayed no significant cytotoxicity towards HeLa cells. Cellular uptake analyses have suggested the effective internalization of DOX-loaded crosslinked micelles and DOX release within cancer cells. These findings suggest that this kind of ROS-triggered reversibly crosslinked polyurethane micelles hold significant potential as a ROS-responsive drug delivery system. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to explore the potential of implementing an action competence teaching model as a framework for achieving sustainable development goals (SDGs) in higher education. The paper seeks to draw insights from the students on the potential of this teaching model. Design/methodology/approach: The study adopted a quantitative research design in exploring the potential of an action competence teaching model. This study used self-report measures to obtain insights into the objective of the study. Findings: The action competence teaching model was seen as useful in equipping students with knowledge about a problem, confidence and willingness to act. However, some issues like the design of the projects, teamwork and instructional practices were identified and discussed. Originality/value: To the best of the authors' knowledge, this study is the first to implement an action competence teaching model to help draw insights from students on its potential. This paper documents certain aspects of action competence that require attention before being implemented in higher education. This information so far lacking in scientific literature contributes to ongoing discussions on SDGs while unveiling strengths and weaknesses to be considered. [ABSTRACT FROM AUTHOR]

A near-infrared fluorescent nanoprobe consisting of Nile blue-capped ZIF-90 is first proposed for real-time imaging of mitochondrial ATP. Owing to the strong binding of ATP with Zn2+, the structure of the probe is disrupted, leading to the release of fluorescent NB. [ABSTRACT FROM AUTHOR]

The current study aimed to verify the multidimensional factor structure of teacher reflection and to examine the psychometric properties of a widely used teacher reflection scale using a large-scale representative dataset of 1,611 practicing Iranian English as a Foreign Language (EFL) teachers. Furthermore, the measurement invariance of the hypothesized, a priori six-factor model of teacher reflection as measured by the adapted scale was assessed across gender and educational degree in Mplus program. In addition, the differences in latent factor means of the same groups were examined. The result of confirmatory factor analysis revealed that teacher reflection was a multidimensional construct, encompassing six underlying factors. Overall, the adapted teacher reflection scale based on the 6-factor model showed an overall good fit. The results also indicated metric and scalar invariance which manifests that the factors underlying the adapted scale had an identical theoretical structure across educational degree/gender groups. Finally, there were significant factor mean differences in reflection components across gender and educational degree groups. A discussion of the results and their implications ensue.

Diffuse large B‐cell lymphoma (DLBCL) is difficult to treat due to the high recurrence rate and therapy intolerance, so finding potential therapeutic targets for DLBCL is critical. FK506‐binding protein 3 (FKBP3) contributes to the progression of various cancers and is highly expressed in DLBCL, but the role of FKBP3 in DLBCL and its mechanism are not clear. Our study demonstrated that FKBP3 aggravated the proliferation and stemness of DLBCL cells, and tumour growth in a xenograft mouse model. The interaction between FKBP3 and parkinsonism associated deglycase (PARK7) in DB cells was found using co‐immunoprecipitation assay. Knockdown of FKBP3 enhanced the degradation of PARK7 through increasing its ubiquitination modification. Forkhead Box O3 (FOXO3) belongs to the forkhead family of transcription factors and inhibits DLBCL, but the underlying mechanism has not been reported. We found that FOXO3 bound the promoter of FKBP3 and then suppressed its transcription, eventually weakening DLBCL. Mechanically, FKBP3 activated Wnt/β‐catenin signalling pathway mediated by PARK7. Together, FKBP3 increased PARK7 and then facilitated the malignant phenotype of DLBCL through activating Wnt/β‐catenin pathway. These results indicated that FKBP3 might be a potential therapeutic target for the treatment of DLBCL. [ABSTRACT FROM AUTHOR]

Hairpin DNA containing split G-quadruplex at its terminus displayed tagging position-dependent horseradish peroxidase activity. In general, the hairpin DNA coupled with one GGG repeat at its 5'-terminus and three GGG repeats at its 3′-terminus demonstrated strong catalytic activity, while slight activity was observed after exchanging the position of split G-quadruplex sequence. Inspired by these observations, a novel colorimetric biosensor for nuclease activity assay was developed by selecting S1 nuclease as the model. Specifically, S1 nuclease cleaves the split G-quadruplex into mono- or oligonucleotide fragments, thereby suppressing the catalytic activity, accompanied by a color change from blue to colorless. Under optimum conditions, S1 nuclease was determined with a linear range from 1.60 to 17.6 U/mL and a detection limit of 1.458 U/mL. The constructed method was simple and did not require complex sequence design, expensive instrumentation, and probe labeling. Most importantly, this work facilitates a better understanding of the catalytic mechanism of the DNAzyme and provides an example of the practical application of G-quadruplex-based DNAzyme. [ABSTRACT FROM AUTHOR]

It has been demonstrated that thymine–guanine (T–G) mismatches in duplex DNA specifically coordinate with mercury ion (Hg2+), forming T–Hg2+–G base pairs. However, the binding performance of T–G mismatches with Hg2+ and its application in biosensors have been rarely reported so far. In this study, the binding between T–G mismatches and Hg2+ was investigated and efforts were made to systematical characterize the analytical performance of T–G mismatches in the determination of Hg2+ and glutathione (GSH), where the thymine–thymine (T–T) mismatches were used as the reference. In specific, Hg2+ induced the conformational change of the fluorescently labeled DNA (FDNA) consisted of seven T–T mismatches, resulting in the dissociation of FDNA with its complementary sequence labeled with a quencher, followed by the disappearance of the fluorescence resonance energy transfer (FRET). The experimental results suggest that the T–G mismatch showed faster signaling kinetics and high sensitivity in sensing Hg2+ with a limit of detection of 4.72 nM for Hg2+. Moreover, the platform based on the T–Hg2+–G structure was successfully applied to determine glutathione with a detection limit of 18.96 nM. These findings of this study may describe the interactions between Hg2+ and nucleobases and extend the applications of Hg2+–mediated base pairs. [ABSTRACT FROM AUTHOR]