Three-Dimensional Digitalized Virtual Planning of Free Anterior Tibial Artery Perforator Flap for Repairing Soft Tissue Defects in Extremities.

BACKGROUND: Traditional research methods have limited the application of anterior tibial artery perforator flap due to incomplete knowledge of the perforator. This study aimed to investigate the feasibility of three-dimensional digitalized virtual planning of free anterior tibial artery perforator flap for repairing soft tissue defects in extremities. METHODS: A total of 11 patients with soft tissue defects in extremities were included. The patient underwent computed tomography angiography (CTA) of bilateral lower limbs, and then the three-dimensional models of bones, arteries, and skin were constructed. Septocutaneous perforators with appropriate length and diameter were selected to design anterior tibial artery perforator flaps in software, and the virtual flaps were superimposed onto the patient's donor site in a translucent state. During the operation, the flaps were dissected and anastomosed to the proximal blood vessel of the defects as designed. RESULTS: Three-dimensional modeling showed clear anatomical relationships between bones, arteries, and skin. The origin, course, location, diameter, and length of the perforator obtained during the operation were consistent with those observed preoperatively. Eleven anterior tibial artery perforator flaps were successfully dissected and transplanted. Postoperative venous crisis occurred in one flap, partial epidermis necrosis occurred in another flap, while the remaining flaps completely survived. One flap was treated with debulking operation. The remaining flaps maintained aesthetic appearance, which did not affect the function of the affected limbs. CONCLUSIONS: Three-dimensional digitalized technology can provide comprehensive information on anterior tibial artery perforators, thus assisting in planning and dissecting patient-specific flaps for repairing soft tissue defects in extremities.

Ego4D: Around the World in 3,000 Hours of Egocentric Video.

We introduce Ego4D, a massive-scale egocentric video dataset and benchmark suite. It offers 3,670 hours of daily-life activity video spanning hundreds of scenarios (household, outdoor, workplace, leisure, etc.) captured by 931 unique camera wearers from 74 worldwide locations and 9 different countries. The approach to collection is designed to uphold rigorous privacy and ethics standards, with consenting participants and robust de-identification procedures where relevant. Ego4D dramatically expands the volume of diverse egocentric video footage publicly available to the research community. Portions of the video are accompanied by audio, 3D meshes of the environment, eye gaze, stereo, and/or synchronized videos from multiple egocentric cameras at the same event. Furthermore, we present a host of new benchmark challenges centered around understanding the first-person visual experience in the past (querying an episodic memory), present (analyzing hand-object manipulation, audio-visual conversation, and social interactions), and future (forecasting activities). By publicly sharing this massive annotated dataset and benchmark suite, we aim to push the frontier of first-person perception. Project page: https://ego4d-data.org/.

Integrated Osteoinductive Factors─Exosome@MicroRNA-26a Hydrogel Enhances Bone Regeneration.

MicroRNAs (miRNAs) are a new therapeutic tool that can target multiple genes by inducing translation repression and target mRNA degradation. Although miRNAs have gained significant attention in oncology and in work on genetic disorders and autoimmune diseases, their application in tissue regeneration remains hindered by several challenges, such as miRNA degradation. Here, we reported Exosome@MicroRNA-26a (Exo@miR-26a), an osteoinductive factor that can be substituted for routinely used growth factors, which was constructed using bone marrow stem cell (BMSC)-derived exosomes and microRNA-26a (miR-26a). Exo@miR-26a-integrated hydrogels significantly promoted bone regeneration when implanted into defect sites; as the exosome stimulated angiogenesis, miR-26a promoted osteogenesis while the hydrogel enabled a site-directed release. Moreover, BMSC-derived exosomes further facilitated healthy bone regeneration by repressing osteoclast differentiation-related genes rather than damaging osteoclasts. Taken together, our findings demonstrate the promising potential of Exo@miR-26a for bone regeneration and provide a new strategy for the application of miRNA therapy in tissue engineering.