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Recombinant protein drugs, which are typically produced by mammalian host cells, have been approved for the treatment of a range of diseases. Accordingly, systems for selecting recombinant cell lines with efficient protein expression and for testing the content of recombinant proteins in vivo are crucial to the large-scale production and application of protein-based therapeutic drugs. In this study, we designed three aptamer beacons to detect His-tag, a common label of recombinant proteins. We found that all three beacons could specifically and quantitatively measure the His-tagged recombinant proteins with a short reaction time. Among these three beacons, the 6H5-MU beacon had the highest sensitivity for His polypeptides with a detection limit of 250 ng/mL and the shortest detection time within 1 min. Furthermore, we established a rapid and highly effective recombinant cell line construction system, which could obtain monoclonal cell lines with high yields of target proteins within 21 days, by combining 6H5-MU with pSB, a novel plasmid composed of a Sleeping Beauty transposase and a transposon. Finally, 6H5-MU also discriminately tested the serum concentration of His-tagged recombinant proteins in vivo, with consistent results compared to enzyme-linked immunosorbent assay (ELISA). We thus established a rapid and high-throughput method for generating recombinant cell lines and in vivo monitoring of recombinant protein levels, thereby providing a new platform for the development and preparation of recombinant protein drugs. KEY POINTS: • The 6H5-MU aptamer beacon rapidly and accurately binds to His-tagged recombinant proteins. • A system for rapid and high-throughput generation of recombinant cell lines is established using 6H5-MU and pSB. • 6H5-MU allows in vivo monitoring of recombinant protein levels.

Augmented reality surgery systems have played an important role in assisting physicians in their operations. However, applying the system to brain neurosurgery is challenging. In addition to using the augmented reality technology to display the 3D position of the surgical target position in real time, we also need to consider the display of the scalpel entry point and scalpel orientation, and their accurate superposition on patients. This paper proposes a mixed reality surgical navigation system, which accurately superimposes the surgical target position, scalpel entry point and scalpel direction on a patient's head and displays it on a tablet, facilitating the visual and intuitive way for the brain neurosurgery. Based on the current neurosurgery navigation system, we integrated mixed reality technology on it. We first independently tested the accuracy of the optical measurement system-NDI Polaris Vicra, and then designed functions that a physician can quickly point out the surgical target position and decide an entry point position, and a tablet can display the superimposed images of surgical target, entry point, and scalpel, and perform the correctness of scalpel orientation. Then we used the Dicom of the patient CT to create a phantom and it’s AR model, imported this AR model into the APP, and installed and executed the APP on the tablet. In the preoperative phase, the technician first superimposed the AR image of head and the scalpel in 5-7 minutes, and then the physician point out and set the target position and entry point position in 2 minutes on a tablet, which then dynamically displayed the superimposed image of the head, target position, entry point position, and scalpel (including the scalpel tip and scalpel spatial direction). We successfully conducted multiple experiments on phantom and six experiments on clinical neurosurgical EVD practice. In the 2D-plane-superposition model (n = 60), the optical measurement system (NDI Polaris Vicra) was feasible of the visualization space with high accuracy (mean error ± standard deviation (SD): 2.013 ± 1.118 mm). In the clinical trials in the hospital (n = 4), the average technician preparation time was 6.317 minutes. The average time (n = 4) required for the physician to set the target position and the entry-point position and accurately overlay the orientation with a surgical stick was 3.5 minutes. In the preparation phase, the average time required for the Dicom image processing and program importing was 120 ± 30 minutes. The designed mixed reality optical surgical navigation system can successfully achieve clinical accuracy, and guide physicians to perform brain surgery visually and intuitively. In addition, the physician can use the APP of the tablet device to instantly obtain Dicom images with the designated patient, change the position of the surgical entry point, and instantly obtain the accurate surgical path and surgical angle after the modification. This design can be used as the basis for various AR or MR brain surgery navigation systems in the future.

Augmented reality surgery systems are playing an increasing role in the operating room, but applying such systems to neurosurgery presents particular challenges. In addition to using augmented reality technology to display the position of the surgical target position in 3D in real time, the application must also display the scalpel entry point and scalpel orientation, with accurate superposition on the patient. To improve the intuitiveness, efficiency, and accuracy of extra-ventricular drain surgery, this paper proposes an augmented reality surgical navigation system which accurately superimposes the surgical target position, scalpel entry point, and scalpel direction on a patient’s head and displays this data on a tablet. The accuracy of the optical measurement system (NDI Polaris Vicra) was first independently tested, and then complemented by the design of functions to help the surgeon quickly identify the surgical target position and determine the preferred entry point. A tablet PC was used to display the superimposed images of the surgical target, entry point, and scalpel on top of the patient, allowing for correct scalpel orientation. Digital imaging and communications in medicine (DICOM) results for the patient’s computed tomography were used to create a phantom and its associated AR model. This model was then imported into the application, which was then executed on the tablet. In the preoperative phase, the technician first spent 5–7 min to superimpose the virtual image of the head and the scalpel. The surgeon then took 2 min to identify the intended target position and entry point position on the tablet, which then dynamically displayed the superimposed image of the head, target position, entry point position, and scalpel (including the scalpel tip and scalpel orientation). Multiple experiments were successfully conducted on the phantom, along with six practical trials of clinical neurosurgical EVD. In the 2D-plane-superposition model, the optical measurement system (NDI Polaris Vicra) provided highly accurate visualization (2.01 ± 1.12 mm). In hospital-based clinical trials, the average technician preparation time was 6 min, while the surgeon required an average of 3.5 min to set the target and entry-point positions and accurately overlay the orientation with an NDI surgical stick. In the preparation phase, the average time required for the DICOM-formatted image processing and program import was 120 ± 30 min. The accuracy of the designed augmented reality optical surgical navigation system met clinical requirements, and can provide a visual and intuitive guide for neurosurgeons. The surgeon can use the tablet application to obtain real-time DICOM-formatted images of the patient, change the position of the surgical entry point, and instantly obtain an updated surgical path and surgical angle. The proposed design can be used as the basis for various augmented reality brain surgery navigation systems in the future.

In this paper, we introduce a linearized energy-preserving scheme which preserves the discrete global energy of solutions to the improved Korteweg−deVries equation. The method presented is based on the finite volume element method, by resorting to the variational derivative to transform the improved Korteweg−deVries equation into a new form, and then designing energy-preserving schemes for the transformed equation. The proposed scheme is much more efficient than the standard nonlinear scheme and has good stability. To illustrate its efficiency and conservative properties, we also compare it with other nonlinear schemes. Finally, we verify the efficiency and conservative properties through numerical simulations.