Developments and current status of cell-free DNA in the early detection and management of hepatocellular carcinoma.

Nowadays, hepatocellular carcinoma (HCC) is still a major threat to human health globally, with a disappointing prognosis. Regular monitoring of patients at high risk, utilizing abdominal ultrasonography combined with alpha-fetoprotein (AFP) serum analysis, enables the early detection of potentially treatable tumors. However, the approach has limitations due to its lack of sensitivity. Meanwhile, the current standard procedure for obtaining a tumor biopsy in cases of HCC is invasive and lacks the ability to assess the dynamic progression of cancer or account for tumor heterogeneity. Hence, there is a pressing need to develop non-invasive, highly sensitive biomarkers for HCC which can improve the accuracy of early diagnosis, assess treatment response and accurately predict the prognosis. In contrast to the conventional method of tissue biopsy, liquid biopsy offers a non-invasive approach that can be readily repeated. As a liquid biopsy approach, the analysis of cell-free DNA (cfDNA) offers real-time insights that can accurately portray the tumor burden and provide a comprehensive depiction of the genetic profile associated with HCC. In this review, we present a comprehensive summary of the recent research findings pertaining to the significance and potential practicality of cfDNA analysis in the early detection and effective management of HCC.

Combination algorithms applied to source reconstruction for neutron coded images and restoration for incomplete coded images.

The neutron emission of compressed capsules filled with fuels in inertial confinement fusion implosions can be measured by neutron imaging systems. Source reconstruction is an important method in coded-aperture imaging. In this paper, we use a combination algorithm to reconstruct the neutron source image. This method can improve the resolution and signal-noise ratio of the reconstructed image. In addition, the ray tracing method is used to obtain the point spread functions of the whole field of view (250 µm), and thus, the system response can be obtained. The edge gray interpolation method is used to restore the missing portion of incomplete coded images. The method can maintain a good performance when the missing-data angle is limited to less than 50°.

mRNA sequencing and CyTOF analysis revealed ASPP2 altered the response patterns of hepatocellular carcinoma HepG2 cells to usnic acid.

In a previous study, our team found that ASPP2 overexpression increases the sensitivity of liver cancer cells to sorafenib. ASPP2 is an important target in the study of drug therapy for hepatocellular carcinoma. In this study, we demonstrated that ASPP2 altered the response of HepG2 cells to usnic acid (UA) by using mRNA sequencing and CyTOF. CCK8 assay was used to detect cytotoxicity of UA on HepG2 cells. Annexin V-RPE assay, TUNEL assay, and cleaved caspase 3 assay were performed to examine the apoptotic cell death induced by UA. Transcriptomic sequencing and a single-cell mass cytometry were used to analyze the dynamic response of HepG2shcon and HepG2shASPP2 cells to UA treatment. We have demonstrated that UA could inhibit proliferation in HepG2 cells in a concentration-dependent manner. Apoptotic cell death was significantly induced by UA in HepG2 cells, while knocking down ASPP2 could increase the resistance of HepG2 cells to UA. Data from mRNA-Seq indicated that knockout of ASPP2 in HepG2 cells affected cell proliferation, cycle, and metabolism. ASPP2 knockdown resulted in increased stemness and decreased apoptosis of HepG2 cells under the action of UA. CyTOF analysis confirmed the above results, ASPP2 knockdown increased oncoproteins in HepG2 cells and altered response patterns of HepG2 cells to UA. Our data suggested that the natural compound UA could inhibit liver cancer HepG2 cells; meanwhile, ASPP2 knockdown could affect response patterns of HepG2 cells to UA. The above results indicate that ASPP2 could be a research target in the chemoresistance of liver cancer.

Robot-Assisted Needle Insertion for CT-Guided Puncture: Experimental Study with a Phantom and Animals.

PURPOSE: This study aimed to evaluate the accuracy and safety of robotic CT-guided needle insertion in phantom and animal experiments. MATERIALS AND METHODS: A robotic system was developed for CT-guided needle insertion. For the phantom experiment, a specially made phantom containing multiple spherical was used. 15 robotic and manual insertions were conducted, and the accuracy, time, number of needle insertions, and radiation dose were compared between the robotic and manual insertion using Student's t-test. For the animal experiment, 20 robotic needle insertions were attempted toward simulated pulmonary nodules in the swine lung. The accuracy and safety of robotic CT-guided needle insertions were evaluated. RESULTS: In the phantom experiment, the mean accuracies of manual and robotic insertion were 1.8 ± 0.3 mm and 1.9 ± 0.2 mm. The accuracy of robotic needle insertion had no significant difference with manual needle insertion, but the number of needle insertions and radiation dose of the robotic needle placement significantly decreased compared to manual needle placement. In the animal experiment, the mean accuracy of the robotic needle insertion was 3.8 ± 1.3 mm. The time for the whole needle insertion was 14.4 ± 4.8 min. The whole robotic needle insertions were safe and only one mild pneumothorax occurred. CONCLUSION: CT-guided robotic needle insertion showed accuracy comparable to manual needle insertion, but the number of needle insertions, confirmatory scans, and radiation exposure had been reduced significantly. In future, we will further apply the robotic system to clinical experiments.

Biomechanical analysis of pelvic holding pathways and strategies for use of the steinmann pin in pelvic fracture reduction.

Pelvic fracture is the most serious bone trauma and has the highest mortality and disability rate. Surgical treatment of pelvic fracture is very challenging for surgeons. Minimally invasive close reduction of pelvic fracture is considered the most difficult operation due to the complex pelvic morphology and abundant soft tissue anatomy, both of which increase the difficulty of pelvic fracture reduction. The most challenging aspect of such surgery is how to hold the pelvic bone and effectively transmit the reduction force to the bone. Therefore, a safe and effective pelvic holding pathway for reduction is necessary for pelvic fracture operations. Existing research on the pelvic holding pathway addresses anatomical position and dimension. Few studies have focused on biomechanical properties or on surgical techniques related to these pathways. This paper studies the three holding pathways that are most commonly used in clinical practice. The most effective force direction for each holding pathway is identified through finite element modeling. Pathway 1 is suitable for internal rotation operation and open/close-book operation of the pelvis; Pathway 2 is suitable for translation of the fractured pelvis toward the sacrum and internal pelvic rotation operations; Pathway 3 is suitable for pulling and lifting of the fractured pelvis against gravity and open/close-book operation of the pelvis. In addition, we find through our simulation that the use of a combined holding strategy can reduce the reduction force during the reduction process. We compared the performances of the 2-pin combined holding strategy (2P-CH) and the 3-pin combined strategy (3P-CH). During translational reduction, 2P-CH and 3P-CH showed little difference in pelvic reduction force. However, in rotational reduction, 3P-CH shows advantages. It has less reduction force and the least combined muscle resistance. It can also maximize the displacement of the iliac crest under the same conditions. The results of this study can be applied to surgical planning and to the development of robot-assisted surgery systems in selecting holding pathways and operation strategies for fractured pelvis.

Design of the scintillator imaging lens for the neutron imaging system at the 100 kJ-level laser facility.

Deuterium-tritium neutron yield has reached up to about 1013 at the 100 kJ-level laser facility, which makes measurement of neutron emission images possible with the neutron imaging system. There are two methods to collect neutron images from the scintillator array, optical fiber taper and the lens system. Here, we report a design of the lens system for the neutron imaging system at the 100 kJ-level laser facility. The lens system, which consists of a nine-element collecting lens, with a spatial resolution of 20 µm and a light-collection efficiency of 5.9% has been designed.

A safe semi-supervised graph convolution network.

In the semi-supervised learning field, Graph Convolution Network (GCN), as a variant model of GNN, has achieved promising results for non-Euclidean data by introducing convolution into GNN. However, GCN and its variant models fail to safely use the information of risk unlabeled data, which will degrade the performance of semi-supervised learning. Therefore, we propose a Safe GCN framework (Safe-GCN) to improve the learning performance. In the Safe-GCN, we design an iterative process to label the unlabeled data. In each iteration, a GCN and its supervised version (S-GCN) are learned to find the unlabeled data with high confidence. The high-confidence unlabeled data and their pseudo labels are then added to the label set. Finally, both added unlabeled data and labeled ones are used to train a S-GCN which can achieve the safe exploration of the risk unlabeled data and enable safe use of large numbers of unlabeled data. The performance of Safe-GCN is evaluated on three well-known citation network datasets and the obtained results demonstrate the effectiveness of the proposed framework over several graph-based semi-supervised learning methods.

A Soft Robotic Gripper Based on Bioinspired Fingers.

In the past, partly due to modeling complexities and technical constraints, fingers of soft grippers are rarely driven by high number of actuators, which leads to lack of dexterity. Here we propose a soft robotic gripper with modular anthropomorphic fingers. Each finger is actuated by four linear drivers, capable of performing forward/backward bending, and abduction/adduction motions. The piecewise constant curvature kinematic model reveals the proposed finger has an ellipsoidal shell workspace analogous to that of a human finger. Furthermore, we build a gripper using two of our modular fingers, and test dexterity and strength of the finger. Our results show that by simple control schemes, the proposed gripper can perform precision grasps and three types of in-hand manipulations that would otherwise be impossible without the addition actuation.

AKT inhibitor AZD5363 suppresses stemness and promotes anti-cancer activity of 3,3'-diindolylmethane in human breast cancer cells.

3,3'-diindolylmethane (DIM) is a dimer compound converted from Indoly-3-carbinol that had been studied as promising chemo-preventive agent against breast cancer. In this study, we observed that proportion of CD133+Nanog+ subpopulation in MCF-7 cells was significantly increased after DIM administration with up-regulated AKT activity by using CyTOF assay. SPADE analysis revealed this stem-like subpopulation exhibited apoptosis-resistance property against DIM treatment. By combining with AKT inhibitor AZD5363, DIM induced CD133 expression could be suppressed. In addition, a combination treatment of MCF-7 and MDA-MB-231 breast cancer cells with DIM and AZD5363 showed synergistic decreases in cell proliferation and induced apoptosis. Furthermore, results from imaging flow cytometry suggested that FoxO3a nuclear localization and PUMA expression could be improved by combination of AZD5363 with DIM. Taken together, the above observations suggested that the combination of AZD5363 with DIM could be developed as potential therapy for breast cancer.

Experimental Study on Timber-Lightweight Concrete Composite Beams with Ductile Bolt Connectors.

A timber-lightweight-concrete (TLC) composite beam connected with a ductile connector in which the ductile connector is made of a stainless-steel bolt anchored with nuts at both ends was proposed. The push-out results and bending performance of the TLC composite specimens were investigated by experimental testing. The push-out results of the shear specimens show that shear-slip curves exhibit good ductility and that their failure can be attributed to bolt buckling accompanied by lightweight concrete cracking. Through the bending tests of ten TLC composite beams and two contrast (pure timber) beams, the effects of different bolt diameters on the strengthening effect of the TLC composite beams were studied. The results show that the TLC composite beams and contrast timber beams break on the timber fiber at the lowest edge of the TLC composite beam, and the failure mode is attributed to bending failure, whereas the bolt connectors and lightweight concrete have no obvious breakage; moreover, the ductile bolt connectors show a good connection performance until the TLC composite beams fail. The ultimate bearing capacities of the TLC composite beams increase 2.03-3.5 times compared to those of the contrast beams, while the mid-span maximum deformation decrease nearly doubled.

Working Pose and Layout Optimization of surgical robot.

It is quite a challenge on positioning surgical robot to optimal place in a crowded and special environment. Compared with the structured industrial environment, the unstructured operating room (OR) environment brings higher requirements for safety of the surgical robot. Meanwhile, the efficiency has significant impact on the ease of surgical robot and repositioning requires additional time and labor. This paper introduces a new method of pose and layout planning to deal with the problem of interaction between robot and environment in operating room. The optimal layout and working pose planning of robot in OR environment are accomplished through APF calculation, pose traversal and layout traversal. The feasibility of this method is validated in simulated OR environment.

A tendon-driven prosthetic hand using continuum structure.

In the current research of prosthetic hands, many degrees of freedom have been omitted in order to simplify the design and reduce the weight, such as the abduction degrees of freedom of the four fingers except the thumb, which impairs the range of mobility of the prosthetic hand to some extent. This paper presents TN hand, a 3D printed, tendon-driven prosthetic hand. We use continuum structure as the finger joint. The other four fingers except the middle finger can perform flexion/extension and abduction/adduction movements, which benefits hand mobility. The design and manufacture of the fingers were elaborated and the finger stiffness was tested through experiment. Then the ability of manipulating daily objects of TN hand was verified based on hand taxonomy. In addition, there is enough range of mobility for the TN hand to perform column chords due to the ability to abduct fingers.

Intraoperative localization of small pulmonary nodules to assist surgical resection: A novel approach using a surgical navigation puncture robot system.

BACKGROUND: Localization and resection of nonvisible, nonpalpable pulmonary nodules during video-assisted thoracoscopic surgery is challenging. In this study we developed a surgical navigation puncture robot system in order to locate small pulmonary nodules before thoracoscopic surgery. METHODS: Four pigs were divided into group A and group B and underwent positioning puncture with the aid of the robotic system. The pigs in group A breathed freely during the experiment, whilst mechanical ventilation was used on the pigs in group B. RESULTS: Using the robotic system to locate nodules achieved good results. For group A, a total of nine simulated nodules were created and successfully localized. The mean positioning accuracy was 9.6 ± 4.9 mm (range, 3.2-17.4 mm), and the time required for system positioning was 7.1 ± 1.0 minutes (range, 5.6-8.2 minutes). For group B, a total of 23 simulated nodules were created and successfully localized. The mean positioning accuracy was 2.9 ± 1.5 mm (range, 0.7-5.9 mm), and the time required for system positioning was 7.8 ± 1.1 minutes (range, 6.3-9.7 minutes). CONCLUSIONS: The new method using a surgical navigation puncture robot system to locate small pulmonary nodules is feasible and safe, and its positioning accuracy is sufficient to meet clinical requirements. In addition, results indicated that breathing had a great influence on the positioning accuracy, mainly in the longitudinal direction. Our surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting. KEY POINTS: Significant findings of the study: A new method using a surgical navigation puncture robot system was developed to locate small pulmonary nodules before thoracoscopic surgery. The results indicated that this method can provide accurate localization and permit smaller and more precise resections. WHAT THIS STUDY ADDS: A surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting.

Implementation of ultraviolet Thomson scattering on SG-III laser facility.

An ultraviolet Thomson-scattering system has been designed and implemented on the Shenguang-III laser facility, a 48-beam, 3ω (351 nm), 180 kJ-level laser driver for high energy density physics and inertial confinement fusion researches. The 4ω (263.3 nm) probe beam of the Thomson-scattering system is injected from the north pole (top) of the target chamber, with an assistant beam-pointing monitor to achieve high pointing accuracy. The Thomson-scattered light is collected by a double-Cassegrain optical transmission system, which provides an achromatic image over a wide wavelength range of 200-800 nm. A novel on-line alignment method is developed and applied to the diagnostic system, ensuring a volumetric positioning accuracy of ∼30 µm for the scattering volume. An online calibration is also conducted to provide the wavelength benchmark and the spectral resolution of the system. This Thomson-scattering system has been tested in a complicated experimental environment with gas-filled hohlraums, and a high-quality ion feature of the scattered light has been obtained.

In-Situ Formed Hydroxide Accelerating Water Dissociation Kinetics on Co3N for Hydrogen Production in Alkaline Solution.

Sluggish water dissociation kinetics on nonprecious metal electrocatalysts limits the development of economical hydrogen production from water-alkali electrolyzers. Here, using Co3N electrocatalyst as a prototype, we find that during water splitting in alkaline electrolyte a cobalt-containing hydroxide formed on the surface of Co3N, which greatly decreased the activation energy of water dissociation (Volmer step, a main rate-determining step for water splitting in alkaline electrolytes). Combining the cobalt ion poisoning test and theoretical calculations, the efficient hydrogen production on Co3N electrocatalysts would benefit from favorable water dissociation on in-situ formed cobalt-containing hydroxide and low hydrogen production barrier on the nitrogen sites of Co3N. As a result, the Co3N catalyst exhibits a low water-splitting activation energy (26.57 kJ mol-1) that approaches the value of platinum electrodes (11.69 kJ mol-1). Our findings offer new insight into understanding the catalytic mechanism of nitride electrocatalysts, thus contributing to the development of economical hydrogen production in alkaline electrolytes.

Backscatter spectra measurements of the two beams on the same cone on Shenguang-III laser facility.

In laser driven hohlraums, laser beams on the same incident cone may have different beam and plasma conditions, causing beam-to-beam backscatter difference and subsequent azimuthal variations in the x-ray drive on the capsule. To elucidate the large variation of backscatter proportion from beam to beam in some gas-filled hohlraum shots on Shenguang-III, two 28.5° beams have been measured with the Stimulated Raman Scattering (SRS) time-resolved spectra. A bifurcated fiber is used to sample two beams and then coupled to a spectrometer and streak camera combination to reduce the cost. The SRS spectra, characterized by a broad wavelength, were further corrected considering the temporal distortion and intensity modulation caused by components along the light path. This measurement will improve the understanding of the beam propagation inside the hohlraum and related laser plasma instabilities.