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Background: Trans-sutural distraction osteogenesis (TSDO) involves the application of distraction force to facial sutures to stimulate osteogenesis. Gli1+ cells in the cranial sutures play an important role in bone growth. However, whether Gli1+ cells in facial sutures differentiate into bone under distraction force is unknown. Methods: 4-week-old Gli1ER/Td and C57BL/6 mice were used to establish a TSDO model to explore osteogenesis of zygomaticomaxillary sutures. A Gli1+ cell lineage tracing model was used to observe the distribution of Gli1+ cells and explore the role of Gli1+ cells in facial bone remodeling. Results: Distraction force promoted bone remodeling during TSDO. Fluorescence and two-photon scanning images revealed the distribution of Gli1+ cells. Under distraction force, Gli1-lineage cells proliferated significantly and co-localized with Runx2+ cells. Hedgehog signaling was upregulated in Gli1+ cells. Inhibition of Hedgehog signaling suppresses the proliferation and osteogenesis of Gli1+ cells induced by distraction force. Subsequently, the stem cell characteristics of Gli1+ cells were identified. Cell-stretching experiments verified that mechanical force promoted the osteogenic differentiation of Gli1+ cells through Hh signaling. Furthermore, immunofluorescence staining and RT-qPCR experiments demonstrated that the primary cilia in Gli1+ cells exhibit Hedgehog-independent mechanosensitivity, which was required for the osteogenic differentiation induced by mechanical force. Conclusions: Our study indicates that the primary cilia of Gli1+ cells sense mechanical stimuli, mediate Hedgehog signaling activation, and promote the osteogenic differentiation of Gli1+ cells in zygomaticomaxillary sutures. [ABSTRACT FROM AUTHOR]

Background: Surgical excision combined with radiotherapy is considered an effective treatment for keloids, while the efficacy and safety of this regimen for huge keloids in patients who need reconstruction after excision is still unclear. Therefore, this study aimed to evaluate the efficacy and safety of surgical excision and reconstruction combined with radiotherapy for huge keloids in a single center with 13 years of experience. Methods: All consecutive patients with huge keloids who underwent surgical excision and reconstruction combined with radiotherapy were identified. Demographic information, prior interventions for keloids, parameters and complications, and recurrence rates were documented. Results: Twenty‐one patients (10 males; mean age, 43.19 ± 18.15 years) were included, 14 patients reconstructed with z‐plasties, 5 with skin grafts, and 2 with skin flaps. During a mean follow‐up of 75 months, one patient developed local necrosis without the need for revision surgery and two patients developed temporary hyperpigmentation. Two patients with the z‐plasties suffered partial keloids recurrence, which was healed with corticosteroid injection. No wound infection, hematoma, telangiectasia, or new keloids at donor sites were observed. The overall appearance of reconstructed defects was aesthetically acceptable. Conclusion: Surgical excision and reconstruction combined with radiotherapy may be safe and effective for huge keloids. [ABSTRACT FROM AUTHOR]

The cathode interlayer plays a vital role in organic solar cells, which can modify the work function of electrodes, lower the electron extraction barriers, smooth the surface of the active layer, and remove solvent residuals. However, the development of organic cathode interlayer lags behind the rapidly improved organic solar cells because their intrinsic high surface tension can lead to poor contact with the active layers. Herein, a double‐dipole strategy is proposed to enhance the properties of organic cathode interlayers, which is induced by incorporating nitrogen‐ and bromine‐containing interlayer materials. To verify this approach, the state‐of‐the‐art active layer composed of PM6:Y6 and two prototypical cathode interlayer materials, PDIN and PFN‐Br is selected. Using the cathode interlayer PDIN: PFN‐Br (0.9:0.1, in wt.%) in the devices can reduce the electrode work function, suppress the dark current leakage, and improve charge extractions, leading to enhanced short circuit current density and fill factor. The bromine ions tend to break from PFN‐Br and form a new chemical bond with the silver electrode, which can adsorb extra dipoles directed from the interlayer to silver. These findings on the double‐dipole strategy provide insights into the hybrid cathode interlayers for efficient non‐fullerene organic solar cells. [ABSTRACT FROM AUTHOR]

With the emergence of nonfullerene acceptors (NFAs), single junction organic solar cells (OSCs) have achieved power conversion efficiencies (PCEs) of over 19%. Due to the intrinsic efficiency limits in low-bandgap NFA OSCs, the donor–to–acceptor energy transfer and acceptor–to–donor hole transfer have considerable impacts on the performance of the OSCs. However, time-resolved ultrafast spectroscopy is often used to prove the energy transfer and hole transfer processes. Herein, we designed thin films and active layers with a tandem structure composed of donors/electron blocking layers/acceptors to demonstrate the occurrence of donor–to–acceptor fluorescence resonance energy transfer (FRET) and acceptor–to–donor hole transfer. By analyzing the steady state photoluminescence peak position and intensity with varied substrate temperatures, FRET from PTO2 to IDTT-IC or IDTT-4FIC and hole transfer from IDTT-IC or IDTT-4FIC to PTO2 were demonstrated. In addition, we monitored devices with a tandem structure active layer using short/long pass filters to excite the donor or acceptor selectively and further confirmed the occurrence of FRET and hole transfer during device operation. Our results proved the effect of FRET and hole transfer directly in thin films and devices, providing a feasible yet practical approach with easily accessible measurements other than ultrafast spectroscopy. [ABSTRACT FROM AUTHOR]