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CRISPR-Cas9 editing triggers activation of the TP53-p21 pathway, but the impacts of different editing components and delivery methods have not been fully explored. In this study, we introduce a p21-mNeonGreen reporter iPSC line to monitor TP53-p21 pathway activation. This reporter enables dynamic tracking of p21 expression via flow cytometry, revealing a strong correlation between p21 expression and indel frequencies, and highlighting its utility in guide RNA screening. Our findings show that p21 activation is significantly more pronounced with double-stranded oligodeoxynucleotides (ODNs) or adeno-associated viral vectors (AAVs) compared to their single-stranded counterparts. Lentiviral vectors (LVs) and integrase-defective lentiviral vectors induce notably lower p21 expression than AAVs, suggesting their suitability for gene therapy in sensitive cells such as hematopoietic stem cells or immune cells. Additionally, specific viral promoters like SFFV significantly amplify p21 activation, emphasizing the critical role of promoter selection in vector development. Thus, the p21-mNeonGreen reporter iPSC line is a valuable tool for assessing the potential adverse effects of gene editing methodologies and vectors. Highlights Established a p21-mNeonGreen reporter iPSC line to track activation of the TP53-p21 pathway. Found a direct correlation between p21-mNeonGreen expression and indel frequencies, aiding in gRNA screening. Showed that LVs are preferable over AAVs for certain cells due to lower p21 activation, with viral promoter choice impacting p21 response. [ABSTRACT FROM AUTHOR]

Aims: Recovery after peripheral nerve injury (PNI) is often difficult, and there is no optimal treatment. Schwann cells (SCs) are important for peripheral nerve regeneration, so SC‐targeting treatments have gained importance. Adipose‐derived stem cells (ADSCs) and their exosomes can promote peripheral nerve repair, but their interactions with SCs are unclear. Methods: Purified SCs from sciatic nerve injury sites were harvested, and apoptosis and proliferation of SCs at post‐PNI 24 hours were analyzed. The effects of coculture with ADSCs and different concentrations of ADSC‐derived exosomes (ADSC‐Exo) were studied through in vitro experiments by flow cytometry, CCK8 assay, immunofluorescence staining, and histological analysis. The expression of the apoptosis‐related genes Bcl‐2 and Bax was also analyzed by qRT‐PCR. Results: ADSC‐Exo reduced the apoptosis of SCs after PNI by upregulating the anti‐apoptotic Bcl‐2 mRNA expression and downregulating the pro‐apoptotic Bax mRNA expression. Further, it also improved the proliferation rate of SCs. This effect was confirmed by the morphological and histological findings in PNI model rats. Conclusion: Our results present a novel exosome‐mediated mechanism for ADSC‐SC cross talk that reduces the apoptosis and promotes the proliferation of SCs and may have therapeutic potential in the future. [ABSTRACT FROM AUTHOR]

Aging of epidermal keratinocytes profoundly impacts skin health, contributing to changes in appearance, barrier function, and susceptibility to diseases. Despite its significance, the molecular mechanisms underlying epidermal aging remain elusive. In this study, a reversible immortalized cell line was established by expressing SV40T in keratinocytes using the Tet-Off lentiviral system. Inducing a senescent phenotype by terminating SV40T expression revealed a significant reduction in mitotic ability, as well as characteristics of cellular aging. RNA sequencing analysis revealed alterations in gene expression and signaling pathways including DNA repair dysfunction, notably senescence-associated secretory phenotype (SASP)-related genes, such as MMP1, SERPINB2 and VEGFA. Our study provides insights into the molecular mechanisms of epidermal aging, offering potential therapeutic targets and highlighting the role of SASP in the aging process.

Background: A crooked nose is an external nose deformity predominantly caused by congenital aplasia or acquired secondary to trauma or surgery, often accompanied by a deviated nasal septum. Patients with crooked nose have dual needs to improve both esthetic and functional problems., Methods: The clinical and photographic information of 48 patients diagnosed with a crooked nose and nasal septum deviation treated from January 2018 to January 2022 was acquired. The morphology and functional effects were investigated by evaluating the general condition of the operation, measuring the esthetic indexes of the nose, and subjectively scoring., Results: For both morphology and function, endoscopy-assisted one-stage correction showed positive results in this study. The external nose deviation distance postoperatively measured 1.28 (0.85, 1.97) mm, which significantly decreased from the preoperative value of 3.96 (3.31, 5.29) mm. The scores of doctors and irrelevant medical students on nose morphology increased significantly from 4.75±1.88 and 3.84±0.76 to 6.48±1.21 and 7.21±0.67, respectively. The rhinoplasty outcome evaluation score and the "nasal obstruction symptom evaluation "score of patients were both significantly improved ( t = -7.508 and t =6.310, respectively, P < 0.001)., Conclusion: Endoscope-assisted one-stage correction of the crooked nose can restore nasal morphology, improve the symptoms of nasal obstruction, and achieve patient satisfaction. It is a minimally invasive, safe, effective, and fast recovery approach for patients who need to solve both esthetic and functional problems., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

The differentiation of natural and synthetic gems is still a difficult problem in gems identification. The full width at half maximum (FWHM) of Raman spectrum, that is the life-span of phonon, can provide valuable information about. natural or synthetic gem. Analysis of the natural and synthetic ruby was performed by BTR111--785 mini-Raman spectroscopy, and it was found that the FWHM of natural ruby is more than 10 cm(-1), withal the FWHM of synthetic ruby is less than 10 cm(-1).