Publications by authors named "Chunbao Liu"

19 Publications

  • Page 1 of 1

A fluid-driven soft robotic fish inspired by fish muscle architecture.

Bioinspir Biomim 2022 Jan 13. Epub 2022 Jan 13.

School of Mechanical Science and Engineering, Jilin University, No.5988 Renmin Street , Nanling Compus, School of Mechanical Science and Engineering, jllin University, Changchun, jilin, 130022, CHINA.

Artificial fish-like robots developed to date often focus on the external morphology of fish and have rarely addressed the contribution of the structure and morphology of biological muscle. However, biological studies have proven that fish utilize the contraction of muscle fibers to drive the protective flexible connective tissue to swim. This paper introduces a pneumatic silicone structure prototype inspired by the red muscle system of fish and applies it to the fish-like robot named Flexi-Tuna. The key innovation is to make the fluid-driven units simulate the red muscle fiber bundles of fish and embed them into a flexible tuna-like matrix. The driving units act as muscle fibers to generate active contraction force, and the flexible matrix as connective tissue to generate passive deformation. Applying alternant pressure to the driving units can produce a bending moment, causing the tail to swing. As a result, the structural design of Flexi-Tuna has excellent bearing capacity compared with the traditional cavity-type and keeps the body smooth. On this basis, a general method is proposed for modeling the fish-like robot based on the independent analysis of the active and passive body, providing a foundation for Flexi-Tuna's size design. Followed by the robot's static and underwater dynamic tests, we used finite element static analysis and fluid numerical simulation to compare the results. The experimental results showed that the maximum swing angle of the tuna-like robot reached 20°, and the maximum thrust reached 0.185 N at the optimum frequency of 3.5 Hz. In this study, we designed a unique system that matches the functional level of biological muscles. As a result, we realized the application of fluid-driven artificial muscle to bionic fish and expanded new ideas for the structural design of flexible bionic fish.
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http://dx.doi.org/10.1088/1748-3190/ac4afbDOI Listing
January 2022

Bioinspired actuators with intrinsic muscle-like mechanical properties.

iScience 2021 Sep 24;24(9):103023. Epub 2021 Aug 24.

Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China.

Humans and animals can achieve agile and efficient movements because the muscle can operate in different modes depending on its intrinsic mechanical properties. For bioinspired robotics and prosthetics, it is highly desirable to have artificial actuators with muscle-like properties. However, it still remains a challenge to realize both intrinsic muscle-like force-velocity and force-length properties in one single actuator simultaneously. This study presents a bioinspired soft actuator, named HimiSK (highly imitating skeletal muscle), designed by spatially arranging a set of synergistically contractile units in a flexible matrix similar to skeletal musculature. We have demonstrated that the actuator presents both intrinsic force-velocity and force-length characteristics that are very close to biological muscle with inherent self-stability and robustness in response to external perturbations. These outstanding properties result from the bioinspired architecture and the adaptive morphing of the flexible matrix material, which adapts automatically to mechanically diverse tasks without reliance on sensors and controllers.
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http://dx.doi.org/10.1016/j.isci.2021.103023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8456066PMC
September 2021

Design of Decision Tree Structure with Improved BPNN Nodes for High-Accuracy Locomotion Mode Recognition Using a Single IMU.

Sensors (Basel) 2021 Jan 13;21(2). Epub 2021 Jan 13.

Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130000, China.

Smart wearable robotic system, such as exoskeleton assist device and powered lower limb prostheses can rapidly and accurately realize man-machine interaction through locomotion mode recognition system. However, previous locomotion mode recognition studies usually adopted more sensors for higher accuracy and effective intelligent algorithms to recognize multiple locomotion modes simultaneously. To reduce the burden of sensors on users and recognize more locomotion modes, we design a novel decision tree structure (DTS) based on using an improved backpropagation neural network (IBPNN) as judgment nodes named IBPNN-DTS, after analyzing the experimental locomotion mode data using the original values with a 200-ms time window for a single inertial measurement unit to hierarchically identify nine common locomotion modes (level walking at three kinds of speeds, ramp ascent/descent, stair ascent/descent, Sit, and Stand). In addition, we reduce the number of parameters in the IBPNN for structure optimization and adopted the artificial bee colony (ABC) algorithm to perform global search for initial weight and threshold value to eliminate system uncertainty because randomly generated initial values tend to result in a failure to converge or falling into local optima. Experimental results demonstrate that recognition accuracy of the IBPNN-DTS with ABC optimization (ABC-IBPNN-DTS) was up to 96.71% (97.29% for the IBPNN-DTS). Compared to IBPNN-DTS without optimization, the number of parameters in ABC-IBPNN-DTS shrank by 66% with only a 0.58% reduction in accuracy while the classification model kept high robustness.
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http://dx.doi.org/10.3390/s21020526DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7828453PMC
January 2021

Locomotor mechanism of based on energy conservation analysis.

Biol Open 2020 12 7;9(12). Epub 2020 Dec 7.

Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China

Spiders use their special hydraulic system to achieve superior locomotor performance and high drive efficiency. To evaluate the variation in hydraulic joint angles and energy conversion during the hydraulic drive of spiders, kinematic data of were collected through a 3D motion capture and synchronization analysis system. Complete stride datasets in the speed range of 0.027 to 0.691 m s were analyzed. Taking the tibia-metatarsu joint as an example, it was found that speed did not affect the angle variation range of the hydraulic joint. Based on the analysis of locomotor mechanics, a bouncing gait was mainly used by during terrestrial locomotion and their locomotor mechanism did not change with increasing speed. Because of the spiders' hydraulic system, the mass-specific power per unit weight required to move the center of mass increased exponentially with increasing speed. The bouncing gait and the hydraulic system contributed to the lower transport cost at low speed, while the hydraulic system greatly increased the transport cost at high speed. The results of this study could provide a reference for the design of high-efficiency driving hydraulic systems of spider-like robots.
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http://dx.doi.org/10.1242/bio.055301DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7746670PMC
December 2020

Application and Evaluation of [Tc]-Labeled Peptide Nucleic Acid Targeting in Breast Cancer Imaging.

Mol Imaging 2020 Jan-Dec;19:1536012120916124

Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

It has been reported that dysregulation of expression and function is associated with tumorigenesis, growth, tumor subtypes, invasion, and poor survival rates. Peptide nucleic acid (PNA), an artificially synthesized nucleic acid mimic, has been applied for molecular diagnosis. In this study, a PNA sequence that undergoes complementary binding to was labeled with Tc to evaluate whether the tracer could visualize the expression of in breast cancer. Both antisense PNA (anti-PNA, fully complementary bound to human mature , referred to as "anti-PNA-155") and mismatched PNA (referred to as "mis-PNA") single strands containing 23-mer were synthesized. The relative expression of in MCF-7 cells and tumors was higher than that in MDA-MB-231 cells and tumors. Single-photon emission computed tomography (SPECT) scan showed that radioactivity mainly accumulated in kidney. MCF-7 tumors, but not MDA-MB-231 tumors, were clearly visualized after [Tc]anti-PNA-155 injection. MCF-7 tumors were less visible when coinjected with 100-fold excess of anti-PNA-155 or injected with [Tc]mis-PNA, which suggested specific binding. Biodistribution study results were consistent with SPECT imaging. We successfully demonstrated that [Tc]anti-PNA-155 could visualize expression in vivo, suggesting it may be a promising probe applied in breast cancer.
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http://dx.doi.org/10.1177/1536012120916124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7307583PMC
July 2021

18F-FDG PET/CT and Serial Chest CT Findings in a COVID-19 Patient With Dynamic Clinical Characteristics in Different Period.

Clin Nucl Med 2020 Jun;45(6):495-496

From the Department of Nuclear Medicine, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Neurological symptoms and gastrointestinal symptoms were rare at onset in COVID-19. Here we report a 37-year-old man with vertigo, fever, and diarrhea symptoms as the first manifestation. F-FDG PET/CT spotted multiple ground glass opacity (GGO) lesions in the lungs, with increased tracer uptake in both lung GGOs and the whole colon. Serial CT examinations showed the emersion and dissipation of lung GGOs. We illustrate the symptoms initiation, the laboratory test results, the imaging examination, and the treatment strategy in the duration of COVID-19 with a timeline chart.
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http://dx.doi.org/10.1097/RLU.0000000000003068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7268872PMC
June 2020

Analysis of Spiders' Joint Kinematics and Driving Modes under Different Ground Conditions.

Appl Bionics Biomech 2019 11;2019:4617212. Epub 2019 Dec 11.

Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China.

Although the hydraulic transmission system in spider legs is well known, the spider's mechanism of locomotion during different terrain conditions still need to be explored further. In this study, spider locomotion was observed in detail on three pavement test platforms: horizontal hard pavement, horizontal soft pavement, and sloped soft pavement. The movement characteristics and joint kinematics of legs were captured by high-speed cameras and Simi Motion 3D tracking software. These observations showed that the gait pattern was basically consistent with an alternating tetrapod gait; however, the pattern observed on the sloped soft pavement was slightly different from that of the two horizontal pavements. In particular, the duty factor of the spiders was 0.683 when walking on the horizontal hard pavement, 0.668 on the horizontal soft pavement, and 0.630 on the sloped soft pavement. The duty factor was greater than 60% in all three pavement environments, which was minimal when walking on the sloped soft pavement. This pattern showed that spiders might have superior stability when walking, but their stability decreased in the sloped soft pavement environment. The ranges of joint angles through the spiders' gait cycles in every pavement environment were also analysed and compared. The findings showed that the hydraulically driven femur-patella and tibia-metatarsal joint angles varied widely, which confirmed that hydraulically driven joints had major functions and obvious effects on the walking process. The kinematic patterns identified in this study provide improved understanding of the hydraulic transmission mechanisms, the factors that affect motion stability, and the design of biomimetic systems.
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http://dx.doi.org/10.1155/2019/4617212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6935789PMC
December 2019

Localized inside-out Ostwald ripening of hybrid double-shelled cages into SnO triple-shelled hollow cubes for improved toluene detection.

Nanoscale 2020 Jan;12(3):2011-2021

College of Materials Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Educations (MOE), and State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, P.R. China.

Unique SnO2 triple-shelled hollow cages with a well-defined cubic shape have been successfully prepared via additional deposition of polycrystalline SnO2 on hybrid Zn2SnO4/SnO2 double-shelled nanotemplates followed by removal of Zn2SnO4. Structural characterization demonstrates that SnO2 triple-shelled hollow cubes (THCs) are hierarchically composed of numerous primary nanoparticles with a size of about several nanometers. The synthetic step-dependent multilayered evolution mechanism can be addressed in terms of different hollowing strategies. Based on the unique less-agglomerated multilayered and porous configuration, the gas sensing performances of SnO2 THCs exhibit an obvious improvement of response and shortened response-recovery characteristics at their optimal working temperature, compared with those of referenced single- and double-shelled SnO2 nanostructures.
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http://dx.doi.org/10.1039/c9nr07489aDOI Listing
January 2020

The art of a hydraulic joint in a spider's leg: modelling, computational fluid dynamics (CFD) simulation, and bio-inspired design.

J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2019 08 29;205(4):491-504. Epub 2019 Apr 29.

School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester, M13 9PL, UK.

Important aspects of spider locomotion rely on a hydraulic mechanism. So far, this has not been theoretically analysed. In this work, the flow mechanism of a main hydraulic joint in a spider leg was studied. The purpose is to gain insight into a biohydraulic mechanism using an engineering approach to improve our understanding of the hemolymph flow path in the spider's legs and to contribute to the theoretical analysis of the spider's hydraulic transmission mechanism, thereby providing an inspiration for advanced biomimetic hydraulic systems. During the study, Micro-CT results were used to reconstruct the detailed flow channel. The high-pressure areas (inlet, joint, and closed leg end) and low pressures in between are also identified. Then, the internal flow field was investigated using computational fluid dynamics. At the same time, the method of dynamic mesh regeneration, elastic smoothing, is used to simulate muscle contraction and joint extension. The different functions of the channels are substantiated by the velocity profiles. Finally, a bionic hydraulic system was designed according to the trajectory of haemolymph in the flow channel.
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http://dx.doi.org/10.1007/s00359-019-01336-2DOI Listing
August 2019

Single-Chain Variable Fragment Antibody of Vascular Cell Adhesion Molecule 1 as a Molecular Imaging Probe for Colitis Model Rabbit Investigation.

Contrast Media Mol Imaging 2019 20;2019:2783519. Epub 2019 Jan 20.

Department of Nuclear Medicine, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China.

Vascular cell adhesion molecule-1 (VCAM-1) can be a promising target for colitis study because of its critical role in inflammation development. Single-chain variable fragment (scFv) antibody presents fast blood clearance when served as an imaging probe. We applied the probe of Tc-scFv-VCAM-1 to colitis rabbit to examine its imaging performance. The colitis model rabbit was prepared, and a typical inflammatory lesion was confirmed in the colon. The probe of Tc-scFv-VCAM-1 was synthesized and injected into the model animal before imaging examination. Scintigraphy detected colitis lesions in both SPECT planar and SPECT/CT fused images, with higher target-to-nontarget ratios in the model group (2.71 ± 0.31) than those in the control group (1.12 ± 0.10). Biodistribution study determined tracer uptake in different organs, and autoradiography (ARG) confirmed probe accumulation in colon lesions. The uptake ratio of the model colon to the control colon was 4.71 ± 0.61 in quantitative analysis of the ARG regions of interest. Stronger VCAM-1 expression in the model colon than that in the control colon was confirmed by western blotting and immunohistochemistry. Our imaging study indicates molecular imaging with scFv-VCAM-1 as a promising way for inflammatory bowel disease diagnosis and evaluation.
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http://dx.doi.org/10.1155/2019/2783519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6360587PMC
August 2019

Fabrication of superhydrophobic bionic surface integrating with VOF simulation studies of liquid drop impacting.

Microsc Res Tech 2019 May 21;82(5):615-623. Epub 2019 Jan 21.

State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun, China.

Superhydrophobic surface has wide application in self-cleaning, anti-pollution, anti-adhesion, drag reduction, but the stable and efficient manufacture of bionic superhydrophobic surfaces is a challenge. We have reproduced the microscopic structure of natural plants and achieved superhydrophobic surface preparation without chemical modification by mechanical process. This program need many experiments to generate processing parameters based on the bionic surface structure. To solve this problem, based on the natural Green Bristlegrass superhydrophobic surface, an optimized bio-inspired striped configuration was presented and the computational fluid dynamics approach was integrated into the fabrication, which was estimated the superhydrophobicity of bio-inspired surface. The volume of fluid (VOF) model and the Level Set function were used to determine the position of the interface during the liquid impact process by solving the change of the volume fraction of each phase in the mixed fluid, thus tracking the gas-liquid phase interface. According to the simulation of striped surface structure, we have processed the bionic samples successfully and they showed an excellent superhydrophobic property, the contact angle was 154° ± 2° and the sliding angle was <5°. The contact time of bionic sample was 12.8 ms. This article used the VOF simulation method to evaluate the design and parameters of the structure, so that the selection of processing parameters were more optimized. Furthermore, the study was essential to access the bio-inspired design and fabrication procedure of superhydrophobic surface.
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http://dx.doi.org/10.1002/jemt.23208DOI Listing
May 2019

Microstructure characteristics and mechanical properties of Meretrix lusoria shell.

Microsc Res Tech 2018 Oct 20;81(10):1154-1161. Epub 2018 Sep 20.

The Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China.

The microstructure and mechanical properties of Meretrix lusoria shell were investigated. M. lusoria shell was comprised of three layers (outer layer, middle layer and inner layer). Outer layer with serried mastoid structure enhanced the connection strength with middle layer. The middle layer consisted of blocky pattern structure with porosity and crossed-lamellar structure. The inner layer exhibited the typical crossed-lamellar structure. Combined with structure characteristic, phase of aragonite confirmed the crossed-lamellar structure further, building material base for mechanical properties including flexure strength (296.26 MPa), compression strength (6.71 MPa) and crack arrest ability. Microstructure of the shell was the function base of crack deflection phenomenon, which dispersed and defused the applied load via the change of crack extension direction. The investigation of M. lusoria shell provided bionic models for the design and fabrication of bioinspired composites in engineering fields. RESEARCH HIGHLIGHTS: Microstructure and mechanical properties of Meretrix lusoria shell were investigated. Crossed-lamellar structure was the microstructure characterization. M. lusoria shell owned high flexure strength and crack arrest property.
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http://dx.doi.org/10.1002/jemt.23107DOI Listing
October 2018

Evaluation of Tc-HYNIC-VCAM-1 as a Potential Qualitative and Semiquantitative Probe Targeting Various Tumors.

Contrast Media Mol Imaging 2018 3;2018:7832805. Epub 2018 May 3.

Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.

Vascular cell adhesion molecule 1 (VCAM-1) is overexpressed in varieties of cancers. This study aimed to evaluate the application of a single chain variable fragment (scFv) of anti-VCAM-1 antibody labeled with Tc as a possible imaging agent in several tumors. VCAM-1 scFv was labeled with Tc using succinimidyl 6-hydrazinium nicotinate hydrochloride, and Tc-HYNIC-VCAM-1 was successfully synthesized with a high radiolabeling yield. VCAM-1 expression was evaluated in six cell lines by immunofluorescence staining. In vitro binding assays showed different binding affinities of Tc-HYNIC-VCAM-1 in different tumor cell lines, with high uptake in B16F10 melanoma and HT1080 fibrosarcoma cells, which was consistent with immunofluorescence staining results. In vivo SPECT planar imaging demonstrated that B16F10 and HT1080 tumors could be clearly visualized. Less intense uptake was observed in human SKOV3.ip ovarian tumor, and weak uptake was observed in human A375m melanoma, MDA-MB-231 breast cancer, and 786-O renal tumors. These findings were confirmed by biodistribution and immunofluorescence studies. High uptake by B16F10 tumors was inhibited by excess unlabeled VCAM-1. Tc-HYNIC-VCAM-1, which selectively binds to VCAM-1, can provide a qualitative and semiquantitative method for noninvasive evaluation of VCAM-1 expression by tumors.
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http://dx.doi.org/10.1155/2018/7832805DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5960529PMC
July 2019

Superhydrophobic surfaces: From nature to biomimetic through VOF simulation.

Micron 2018 04 9;107:94-100. Epub 2018 Feb 9.

Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China. Electronic address:

The contact angle, surface structure and chemical compositions of Canna leaves were investigated. According to the surface structure of Canna leaves which observed by Scanning Electron Microscopy(SEM), the CFD (Computational Fluid Dynamics)model was established and the method of volume of fluid (VOF) was used to simulate the process of droplet impacting on the surface and established a smooth surface for comparison to verify that the surface structure was an important factor of the superhydrophobic properties. Based on the study of Canna leaf and VOF simulation of its surface structure, the superhydrophobic samples were processed successfully and showed a good superhydrophobic property with a contact angle of 156 ± 1 degrees. A high-speed camera (5000 frames per second) was used to assess droplet movement and determine the contact time of the samples. The contact time for the sample was 13.1 ms. The results displayed that the artificial superhydrophobic surface is perfect for the performance of superhydrophobic properties. The VOF simulation method was efficient, accurate and low cost before machining artificial superhydrophobic samples.
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http://dx.doi.org/10.1016/j.micron.2018.01.013DOI Listing
April 2018

PET Imaging of VCAM-1 Expression and Monitoring Therapy Response in Tumor with a Ga-Labeled Single Chain Variable Fragment.

Mol Pharm 2018 02 24;15(2):609-618. Epub 2018 Jan 24.

Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan 430022, China.

Vascular cell adhesion molecule-1 (VCAM-1) is a transmembrane glycoprotein closely related to tumorigenicity as well as tumor metastasis. It is also a well-known candidate for detecting tumors. LY2409881, an IKKβ inhibitor, could induce apoptosis of VCAM-1 positive cells. Our purpose is to prepare a novel tracer to evaluate its feasibility of detecting VCAM-1 expression and monitoring LY2409881 tumor curative effect. The tracer was prepared by conjugating the single chain variable fragment (scFv) of VCAM-1 and NOTA-NHS-ester and then labeled with Ga. Ga-NOTA-VCAM-1 was successfully prepared with high radiochemical yield. VCAM-1 overexpression and underexpression melanoma cell lines, B16F10 and A375m, were used in this study. The results of microPET/CT imaging in small animals indicated that the uptake of Ga-NOTA-VCAM-1 in B16F10 tumor was much higher than that of A375m, which was also confirmed by the biodistribution and autoradiography results. LY2409881 inhibits the growth of B16F10 melanoma in vivo by inducing dose- and time-dependent growth inhibition and apoptosis of the cells. The LY2409881 treated group and DMSO control group were established and imaged by microPET/CT. In the LY2409881 group, uptake of the tracer in tumor was decreased at the first week, and then gradually recovered to the initial level. In DMSO control, the uptake of the tracer remained at the same level during the whole time. The results suggested that LY2409881 inhibits the expression of VCAM-1 and suppresses tumor growth. Ga-NOTA-VCAM-1, an easily synthesized probe, has a potential clinical application in the visual monitoring of IKKβ inhibitor intervention on VCAM-1 positive tumors.
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http://dx.doi.org/10.1021/acs.molpharmaceut.7b00961DOI Listing
February 2018

Detection of melanoma metastases with PET-Comparison of F-5-FPN with F-FDG.

Nucl Med Biol 2017 Jul 7;50:33-38. Epub 2017 Apr 7.

Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Hubei Key Laboratory of Molecular Imaging, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address:

Introduction: F-5-fluoro-N-(2-(Diethylamino)ethyl)picolinamide (F-5-FPN) is a new positron-emission tomography (PET) radiopharmaceutical with potential for the detection of lymph node (LN) and pulmonary metastatic lesions of melanoma. We compared its performance with that of F-deoxyglucose (F-FDG).

Methods: Cervical LN and lung melanoma metastasis models were established in C57BL/6 mice. Primary tumors were created by injection of melanoma cells into the pinna, and the resulting cervical LN metastases were evaluated. Lung metastases were created by intravenous injection of melanoma cells. The mice underwent F-FDG and F-5-FPN positron emission tomography (PET) imaging. A biodistribution study was conducted after imaging. Histopathologic evaluation of the tumors was also performed.

Results: LN metastases with a diameter<1cm were more visible on F-5-FPN PET imaging than F-FDG imaging. Quantitative analysis showed that the uptake of F-5-FPN was significantly higher than that of F-FDG, with values of 13.29±3.80% ID/g and 7.24±1.95% ID/g (n=5, P<0.05), respectively. LN-to-muscle ratios were 21.23±6.02 and 4.50±2.11 (n=5, P<0.01) for F-5-FPN and F-FDG, respectively. Biodistribution results were similar, with high uptake of F-5-FPN in the LN. F-5-FPN imaging manifested the pulmonary lesions clearly, while the F-FDG imaging showed no uptake in lesions <2mm. The related uptakes of F-5-FPN and F-FDG were 3.12±1.17% ID/g and 1.48±0.15% ID/g, respectively (n=5, P<0.05), with lung metastasis-to-muscle ratios of 8.16±3.12 and 1.28±0.18 (n=5, P<0.01), respectively. H&E and Prussian blue staining displayed pluri nucleated or mega nucleus cells and dark brown granules in the metastatic tissues, characteristic of melanoma.

Conclusions: F-5-FPN targeted small metastatic lesions with a higher target-to-normal ratio of uptake than those of F-FDG, which suggests its ability to detect metastatic lesions earlier than F-FDG. Further studies with a wide range of melanoma cell lines should be needed to confirm the similar performance.
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http://dx.doi.org/10.1016/j.nucmedbio.2017.03.005DOI Listing
July 2017

Substitution mapping of QTLs controlling seed dormancy using single segment substitution lines derived from multiple cultivated rice donors in seven cropping seasons.

Theor Appl Genet 2017 Jun 10;130(6):1191-1205. Epub 2017 Mar 10.

State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources and Guangdong Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.

Key Message: A permanent advanced population containing 388 SSSLs was used for genetic analysis of seed dormancy; 25 QTLs including eight stable, six major and five new were identified. Seed dormancy (SD) is not only a complex biological phenomenon, but also a key practical problem in agricultural production closely related with pre-harvest sprouting (PHS). However, the genetic mechanisms of SD remain elusive. Here, we report the genetic dissection of SD in rice using 388 single segment substitution lines (SSSLs) derived from 16 donor parents. Continuous variation and positive correlations in seed germination percentages were observed in seven seasons. Genetic analysis revealed the narrow sense heritability in different seasons varied from 31.4 to 82.2% with an average value of 56.8%. In addition, 49 SSSLs exhibited significant difference to recipient parent HJX74 on SD in at least two seasons, and 12 of them were stably identified with putative QTLs in all of their corresponding cropping seasons. Based on substitution mapping, a total of 25 dormancy QTLs were detected on 11 chromosomes except the chromosome 5 with an interval length of 1.1 to 31.3 cM. The additive effects of these QTLs changed from -0.31 to -0.13, and the additive effect contributions ranged from 16.7 to 41.4%. Six QTLs, qSD3-2, qSD4-1, qSD7-1, qSD7-2, qSD7-3 and qSD11-2, showed large additive effect contributions (≥30%). Five QTLs, qSD3-3, qSD7-1, qSD7-4, qSD9-1 and qSD10-1, may represent novel ones. Furthermore, linkage and recombinant analysis delimited qSD7-1 to a locus 1.5 cM away from marker Oi2 and a 355-kb fragment flanked by RM1134 and Ui159, respectively. Taken together, this work conducts a comprehensive genetic dissection of SD and will provide more selections for breeding elite PHS-resistant rice varieties.
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http://dx.doi.org/10.1007/s00122-017-2881-9DOI Listing
June 2017

Drag Reduction and Performance Improvement of Hydraulic Torque Converters with Multiple Biological Characteristics.

Appl Bionics Biomech 2016 26;2016:3641651. Epub 2016 Sep 26.

School of Mechanical Science and Engineering, Jilin University, Changchun, China.

Fish-like, dolphin-like, and bionic nonsmooth surfaces were employed in a hydraulic torque converter to achieve drag reduction and performance improvement, which were aimed at reducing profile loss, impacting loss and friction loss, respectively. YJSW335, a twin turbine torque converter, was bionically designed delicately. The biological characteristics consisted of fish-like blades in all four wheels, dolphin-like structure in the first turbine and the stator, and nonsmooth surfaces in the pump. The prediction performance of bionic YJSW335, obtained by computational fluid dynamics simulation, was improved compared with that of the original model, and then it could be proved that drag reduction had been achieved. The mechanism accounting for drag reduction of three factors was also investigated. After bionic design, the torque ratio and the highest efficiencies of YJSW335 were both advanced, which were very difficult to achieve through traditional design method. Moreover, the highest efficiency of the low speed area and high speed area is 85.65% and 86.32%, respectively. By economic matching analysis of the original and bionic powertrains, the latter can significantly reduce the fuel consumption and improve the operating economy of the loader.
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http://dx.doi.org/10.1155/2016/3641651DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5056315PMC
September 2016

SPECT and fluorescence imaging of vulnerable atherosclerotic plaque with a vascular cell adhesion molecule 1 single-chain antibody fragment.

Atherosclerosis 2016 11 13;254:263-270. Epub 2016 Sep 13.

Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, China; Hubei Province Key Laboratory of Molecular Imaging, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address:

Background And Aims: Early detection and evaluation of vulnerable atherosclerotic plaque are important for risk stratification and timely intervention, and vascular cell adhesion molecule 1 (VCAM1) assists in adhesion and recruitment of inflammatory cells to vulnerable lesions. We labeled a single-chain variable fragment (scFv) of VCAM1 with technetium (Tc) and fluorescent markers to investigate its potential utility in detecting vulnerable plaques in animal models of atherosclerosis.

Methods: We labeled VCAM1 scFv with Tc and cyanine5 (CY5) and evaluated the probes on apolipoprotein E gene-deficient mice and New Zealand White rabbits with induced atherosclerosis. Histopathology and Western blot examinations confirmed atherosclerotic plaque and VCAM1 expression in the aortas. In vivo biodistribution of Tc-scFv-VCAM1 was studied. Abdominal organs of mice were removed after CY5-scFv-VCAM1 administration for aortic fluorescence imaging. Rabbits SPECT imaging of Tc-scFv-VCAM1 was performed and autoradiography (ARG) of the aortas was checked to confirm the tracer uptake.

Results: The radiochemical purity of Tc-scFv-VCAM1 was 98.72± 1.04% (n = 5) and its specific activity was 7.8 MBq/μg. Biodistribution study indicated predominant probe clearance by kidneys. In fluorescence imaging, stronger signal from CY5-scFv-VCAM1 in the aorta was observed in atherosclerotic mice than that in controls. SPECT imaging with Tc-scFv-VCAM1 showed tracer uptake in the abdominal aorta and the aortic arch of atherosclerotic animals. ARG confirmed tracer uptake in the aortas of atherosclerotic rabbits, with higher uptake ratios of aortic arch/descending aorta in experimental animals (4.45 ± 0.63, n = 5) than controls (1.12 ± 0.15, n = 5; p < 0.05).

Conclusions: SPECT and fluorescence imaging results showed the feasibility and effectiveness of detecting vulnerable plaque with scFv of VCAM1, indicating its potential for early diagnosis and evaluation of atherosclerosis.
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http://dx.doi.org/10.1016/j.atherosclerosis.2016.09.005DOI Listing
November 2016
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