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Directional differentiation of stem cells is a key step in stem cell therapy. In this study, we developed saponin-based nanoparticles (Ad-SNPs) containing dexamethasone (Dex) and alpha-lipoic acid (ALA) to promote osteogenic differentiation of human mesenchymal stem cells (hMSCs) and bone regeneration. The Ad-SNPs can achieve rapid cellular uptake through a pore-forming effect without cytotoxic cationic charges. They also provide extended retention in cell cytosol due to their uptake route. These properties are advantageous in efficiently supplying drugs to the hMSCs. The combination of Dex and ALA facilitated mitochondrial fusion and prevented reactive oxygen species–induced DNA damage. It also helped to preserve mitochondrial dynamics, and the efficient supply of it provided by the Ad-SNPs induced differentiation of hMSCs into osteoblasts. The Ad-SNPs showed outstanding performance in osteoblast differentiation, maturation, and mineralization in 3D culture compared with NPs without saponin and with free drugs. When Ad-SNP-treated hMSCs were tested in a rat femoral bone defect model, they showed the fastest regeneration of bones and complete repair in the shortest period among all groups. To the best of our knowledge, this study is the first application of pore-forming saponin-based NPs with rapid cellular uptake and extended retention to stem cell therapy, and we demonstrated their promising potential in bone regeneration and efficient delivery of Dex and ALA. Saponin nanoparticle can provide efficient supply of dexamethasone and alpha-lipoic acid in mesenchymal stem cells via pore-forming effect. It promotes in vivo osteogenic differentiation and bone regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

• Biliteracy. • Translanguaging. • Heritage language learning. • Korean bilingual children. • Heteroglossia perspectives. Qualitative discourse analysis and case study methodologies were employed, along with heteroglossic and sociocultural theories, to analyze the written translanguaging practices of four Korean-American first-graders over 14 weeks at a Korean heritage language school in the U.S. Written translanguaging characterized 21–31% of the writing produced by the three students who preferred English, and 3% of the writing produced by the student who preferred Korean. All four students demonstrated written translanguaging for metalinguistic and sociolinguistic functions, demonstrating their agency, bilingual identities, and audience orientation. Two students employed metatalk to problem-solve their writing, indicating metacognitive insight. The three students who translanguaged often appeared to be more interested in communication than in the form of their writing. The fourth student's written translanguaging involved transliteration for English proper nouns and unknown Korean words. Because the students were not taught translanguaging, their use of it appeared to be a natural byproduct of their bilingual status. [ABSTRACT FROM AUTHOR]