Objective To construct a new type of glucosamine/DNA composite nanostructure(NTGlcN)assembled without magnesium,verify whether or not glucosamine can mediate the assembly of DNA nanotubes(NT)and assess its effect on the function of Raw264.7 cells.Methods Utilizing the gradient annealing method with 3 DNA single strands Y1,Y2,and Y3,glucosamine(GlcN)was employed to mediate the assembly of DNA NT,resulting in the formation of glucosamine/DNA composite nanostructures.Atomic force microscopy(AFM)was used to observe the surface structure of the nanomaterial and dynamic light scattering(DLS)was used to measure its size.RAW264.7 cells were used in cell experiments.The cytotoxicity of GlcN and NTGlcN was assessed using CCK-8 assay.Flow cytometry and laser confocal microscopy were employed to investigate the cellular uptake efficiency of the nanostructures.The effects of NTGlcN and NTMg(Mg2+-assembled of DNA NT)on the expression levels of inflammatory cytokines(IL-1β,IL-6)in macrophages induced by lipopolysaccharides(LPS)were evaluated using RT-qPCR.Results GlcN successfully mediated the synthesis of NTGlcN,which exhibited good stability.AFM characterization results revealed that NTGlcN formed tubular particles that were uniformly distributed on the surface of mica.DLS measurements indicated that the diameter of NTGlcN was approximately 15.26±3.86 nm.Cell experiments demonstrated that,compared to NTMg,macrophages exhibited a higher cellular uptake efficiency for NTGlcN,with a higher cell survival rate following treatment with NTGlcN(P＜0.05).After NTGlcN treatment,the expression of inflammatory cytokines in LPS-induced macrophages was reduced(P＜0.05).Conclusion The glucosamine/DNA composite nanostructures have been successfully developed,possessing excellent stability,biocompatibility and cell uptake efficiency.NTGlcN is capable of reducing the cytotoxicity of GlcN and can suppress cellular inflammatory responses by decreasing the expression of inflammatory cytokines in RAW264.7 cells.

ObjectiveTo develop a direct teaching technology (teaching and teaching reproduction) of an end-traction upper limb rehabilitation robot, in allusion to the difference between the upper limb training trajectory and training intensity of different patients. MethodsA direct teaching method based on Moveit was proposed, to realize the stable teaching of the upper limb rehabilitation robot, by adding upper limb gravity compensation and constraint step conversion control. After the six-dimensional force sensor collecting the force/torque information, the coordinate transformation, upper limb gravity compensation and constraint step conversion algorithm were used in Robot Operating System (ROS), so that the upper limb of the patient and the end of the mechanical arm could comply with the direction of the drag force of the rehabilitation therapist track, and recorded the teaching track at the same time. In ROS, Moveit was used to write a teaching and reproduction node, which was used to adjust the training times, training speed and rest time of rehabilitation training, and conduct training. Through Moveit's kinematics solution and trajectory planning for the taught trajectory information, the rehabilitation robot could accurately drive the affected limb for reciprocating training, thereby achieving the effect of personalized training. ResultsThe instructors dragged the upper limbs of five healthy subjects in the horizontal plane, sagittal plane and coronal plane training modes to complete the same training action, and completed any curve movement in the space training mode. The direct teaching took about four to seven seconds and the obtained trajectory was smooth and the direction conformed to the direction of force. Due to difference in the height of the subjects and the length of each part of the upper limbs, the five subjects had different trajectories and positions when completing the same training exercise. The instructor set appropriate training intensity parameters through the human-computer interaction interface and trained five subjects in each mode. The subjects had regular movements and felt comfortable during training. The trajectory of subject three, which was closest to the average value, was selected to train five subjects. It was found that all subjects except subject three had irregular training movements, unstretched or overstretched, etc. ConclusionThe direct teaching system of the end-traction type upper limb rehabilitation robot can well help the instructor teach the multi-degree-of-freedom upper limb training trajectory suitable for different subjects easily, quickly and stably. Rehabilitation training of different intensities is carried out by reproducing the trajectory, which has the characteristics of simple operation, strong pertinence and accurate training.

Objective: To investigate the initial clinical value of shear wave elastography (SWE) combined with shear wave dispersion (SWD) in preoperatively differentiating diagnosis of focal liver lesions (FLLs). Methods: Eighty-three patients diagnosed as FLLs were prospectively enrolled from January to April 2018 in Zhongshan Hospital of Fudan University. Measurements of SWD and SWE both inner FLLs and surrounding liver parenchyma 2 cm away from the board lines of lesions were performed. ROIs were placed within the lesions and surrounding parenchyma 2 cm away from the lesions. In each ROI, measurements were performed 13 times. Histopathological results after operation were regarded as gold standard, and the values of viscoelasticity in differentiating diagnosis of FLLs were analyzed. Results: The final histopathological results showed that of all 83 cases, 20 cases were diagnosed as benign lesions (5 cases of focal nodular hyperplasia, 15 cases of hemangioma), and 63 cases as malignant lesions (12 cases of liver metastases, 51 cases of hepatocellular carcinoma). The SWE of benign lesions and malignant lesions were (9.94±8.22)kPa, and (13.68±7.80)kPa(P<0.05). The SWD of benign lesions and malignant lesions were (13.47±2.76)(m/s)/kHz, and (15.00±3.82)(m/s)/kHz(P<0.05). The SWE ratio and SWD ratio of benign lesions to surrounding liver parenchyma were higher than those of malignant lesions(all P<0.05). The SWE ratio of benign and malignant lesions were 2.60±2.65, and 1.40±1.40, respectively (P<0.05). The SWD ratio of benign and malignant lesions were 0.92±0.44, and 0.80±0.51, respectively(P<0.05). Conclusions With the advantages of effectiveness, convenience, non-invasiveness and repeatability, combined measurement of SWE and SWD has a potential value in differentiating diagnosis of liver lesions.

Objective To investigate the value of contrast‐enhanced ultrasound ( CEUS ) in the differential diagnosis of pancreatic neoplasia ( SPN ) before operation . Methods Forty‐six cases of SPN confirmed by operation and histopathological results from January 2012 to June 2018 were enrolled in the study . According to the European Ultrasound Association ( EFSUMB) guidelines for CEUS in 2018 ,the enhancement pattern of pancreatic lesion with normal surrounding pancreatic parenchyma was used for reference . T he enhancement pattern of SPN were observed during the arterial phase ,venous phase and delayed phase . CEUS pattern of 16 cases with pancreatic ductal adenocarcinoma ( PDAC ) with cystic changes proved by histopathology were observed and compared with SPN . Results T he mean size of 46 cases of SPN was ( 32 .72 ± 25 .51) mm . Fifteen SPN lesions located in the head of pancreas ,31 cases located in the body and tail of the pancreas . Most of SPN were solidcystic lesions with thin separation on conventional B mode ultrasoud ,without communication with the main pancreatic duct . Color flow signals could be detected in 78 .3% ( 36/46) SPN lesions . After the injection of 2 .4 ml ultrasound contrast agent , the substantial part of all SPN showed hyperenhancement ( n＝ 44 ,99 .7% ) or isoenhancement ( n ＝ 2 , 4 .3% ) during the arterial phase ,venous phase and late phase . However ,93 .8% ( 15/16 ) of the PDAC lesion with cystic changes showed consistent hypo enhancement throughout the arterial ,venous and late phase ( P ＜0 .05) . T he accuracy of preoperative diagnosis of CEUS was 95 .6% . Conclusions Depending on its unique advantages such as real‐time observation ,high‐resolution imaging ,and no radiation ,CEUS is helpful for early detection ,accurate localization and preoperative diagnosis of SPN . CEUS has potential role for clinical decision‐making before treatment .

Objective To investigate the initial clinical value of shear wave elastography ( SWE ) combined with shear wave dispersion ( SWD) in preoperatively differentiating diagnosis of focal liver lesions ( FLLs) . Methods Eighty‐three patients diagnosed as FLLs were prospectively enrolled from January to April 2018 in Zhongshan Hospital of Fudan University . M easurements of SWD and SWE both inner FLLs and surrounding liver parenchyma 2 cm away from the board lines of lesions were performed . ROIs were placed within the lesions and surrounding parenchyma 2 cm away from the lesions . In each ROI , measurements were performed 13 times . Histopathological results after operation were regarded as gold standard ,and the values of viscoelasticity in differentiating diagnosis of FLLs were analyzed . Results The final histopathological results showed that of all 83 cases ,20 cases were diagnosed as benign lesions ( 5 cases of focal nodular hyperplasia ,15 cases of hemangioma) ,and 63 cases as malignant lesions ( 12 cases of liver metastases ,51 cases of hepatocellular carcinoma) . T he SWE of benign lesions and malignant lesions were ( 9 .94 ± 8 .22) kPa ,and ( 13 .68 ± 7 .80) kPa( P ＜0 .05 ) . T he SWD of benign lesions and malignant lesions were ( 13 .47 ± 2 .76 ) ( m/s)/kHz ,and ( 15 .00 ± 3 .82 ) ( m/s)/kHz ( P ＜0 .05 ) . T he SWE ratio and SWD ratio of benign lesions to surrounding liver parenchyma were higher than those of malignant lesions( all P ＜