Preparation, identification and molecular docking of two novel anti-aging peptides from perilla seed.

Perilla seed meal is an important agricultural by-product of perilla oil extraction. The antioxidant and anti-aging activities of perilla seed meal protein hydrolysate were investigated, and the bioactive peptides were identified to maximize the utilization of perilla seed meal resources. Anti-aging peptides were identified using a combination of peptidomics and in silico bioinformatics. Furthermore, the potential molecular mechanism of these peptides was explored through molecular docking and RT-PCR. The results showed a significant anti-aging properties of F2 (MW 3 kDa ∼5 kDa) by inhibition of reactive oxygen species (ROS) production and ß-galactosidase activity. Nine novel peptides were identified from F2 and subsequently synthesized to explore their bioactivities. The two peptides, NFF and PMR, were found to promote the proliferation of keratinocytes (HaCaT cells) and suppress the level of ROS and the activity of ß-galactosidase. Both peptides exhibited a strong binding affinity with the Keap1 protein. Additionally, NFF and PMR downregulated the expression of matrix metalloproteinases (MMPs) and the degradation of collagens (COLs). The potential molecular mechanism underlying the anti-aging properties of perilla seed meal peptides might involve the competitive binding of Keap1 to facilitate the release of Nrf2 and activation of NF-κB signal pathway. This study provides a theoretical basis for the application of perilla seed meal peptides in functional cosmetics and presents a novel perspective for the investigation of additional food-derived peptides.

Distributed visual positioning for surgical instrument tracking.

In clinical operations, it is crucial for surgeons to know the location of the surgical instrument. Traditional positioning systems have difficulty dealing with camera occlusion, marker occlusion, and environmental interference. To address these issues, we propose a distributed visual positioning system for surgical instrument tracking in surgery. First, we design the marker pattern with a black and white triangular grid and dot that can be adapted to various instrument surfaces and improve the marker location accuracy of the feature. The cross-points in the marker are the features that each feature has a unique ID. Furthermore, we proposed detection and identification for the position-sensing marker to realize the accurate location and identification of features. Second, we introduce multi Perspective-n-Point (mPnP) method, which fuses feature coordinates from all cameras to deduce the final result directly by the intrinsic and extrinsic parameters. This method provides a reliable initial value for the Bundle Adjustment algorithms. During instrument tracking, we assess the motion state of the instrument and select either dynamic or static Kalman filtering to mitigate any jitter in the instrument's movement. The core algorithms comparison experiment indicates our positioning algorithm has a lower reprojection error comparison to the mainstream algorithms. A series of quantitative experiments showed that the proposed system positioning error is below 0.207 mm, and the run time is below 118.842 ms. The results demonstrate the tremendous clinical application potential of our system providing accurate positioning of instruments promoting the efficiency and safety of clinical surgery.

Numerical Analysis of Stress Force on Vessel Walls in Atherosclerotic Plaque Removal through Coronary Rotational Atherectomy.

Coronary rotational atherectomy is an effective technique for treating cardiovascular disease by removing calcified tissue using small rotary grinding tools. However, it is difficult to analyze the stress force on vessel walls using experiments directly. Using computational fluid dynamics is a better way to study the stress force characteristics of the burr grinding procedure from a fluid dynamics perspective. For this purpose, physical and simulation models of atherosclerotic plaque removal were constructed in this study. The simulation results show that smaller ratios between the burr and arterial diameter (B/A = 0.5) result in a more stable flow field domain. Additionally, the pressure and stress force generated by the 4.5 mm diameter grinding tool reach 92.77 kPa and 10.36 kPa, surpassing those of the 2.5 mm and 3.5 mm grinding tools. The study has demonstrated the use of computational fluid dynamics to investigate wall shear stress characteristics in medical procedures, providing valuable guidance for optimizing the procedure and minimizing complications.

Application value of 3D printing technology in the surgery of sphenoid ridge meningioma / 中国肿瘤临床

Objective:To investigate the value of 3D printing technology in sphenoid ridge meningioma dissection. Methods:By using craniocerebral spiral enhanced CT scan DICOM images, the skull, vessels, and tumor were extracted, reconstructed, and assembled and integrated in the same coordinate system. Then, we constructed a 3D virtual model and a 3D-printed entity model, which was ap-plied for preoperation and postoperation. Results:Virtual models of the brains of five patients were reconstructed successfully and 3D entity models were produced. The models expressed the relationship among tumors, adjacent blood vessels, and the important posi-tion of the nerve tissue. Then, the models were applied to the reference before surgery planning and after surgery. Five cases were successfully performed. Conclusion:The use of the entity model of sphenoid ridge meningioma is important in optimizing operation plans, improving tumor resection, and reducing intraoperative bleeding.