University of Hong Kong View Institution's Website 26 articles published in JoVE Medicine Examination of Oral Candida Infection in Primary Sjögren's Syndrome Patients Xiaoyan Wang1,2,3, Yeqing Song4, Xinzhe Lou1, Bingqing Han5,6,7, Ruiqing Wu1, Jing Xie8,9, Xiang Lin8,9, Hao Wang1 1Department of Stomatology, Beijing Tiantan Hospital, Capital Medical University, 2Beijing Laboratory of Oral Health, Capital Medical University, 3Department of Biochemistry and Molecular Biology, School of Basic Medicine, Capital Medical University, 4Central Laboratory, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, 5Clinical Diagnosis Laboratory of Beijing Tiantan Hospital, Capital Medical University, 6Key Laboratory for Quality Control of In Vitro Diagnostics, NMPA, 7Beijing Engineering Research Center of Immunological Reagents Clinical Research, 8School of Chinese Medicine, The University of Hong Kong, 9Department of Rheumatology and Clinical Immunology, Beijing Tiantan Hospital, Capital Medical University Here, we present a protocol for the examination of oral Candida infection in patients with primary Sjögren's syndrome, which can be used for timely treatment and, thereafter, avoiding related complications. Developmental Biology Generation of Natural Killer Cells from Human Expanded Potential Stem Cells Poon Yu Ching1, Clement Wang2, Su Hang2, Pentao Liu2,3, Ryohichi Sugimura2,3 1Major in Molecular Biology and Biotechnology, School of Biological Sciences, The University of Hong Kong, 2School of Biomedical Sciences, The University of Hong Kong, 3Centre for Translational Stem Cell Biology The present protocol shows how to differentiate CD3−/CD45+CD56+ cells with mild cytotoxicity from human expanded potential stem cells (hEPSCs) under both 3D and 2D culture conditions. This allows for routine phenotypical validation without the destruction of the complex microenvironment. Medicine Laparoscopic Non-Mesh Cerclage Pectopexy for Pelvic Organ Prolapse Wenju Zhang*1, Willy Cecilia Cheon*2, Hextan Yuen Sheung Ngan*3, Yuzhen Wei1, Chaoxia Lyu1 1Department of Gynecology and Obstetrics, The University of Hong Kong-Shenzhen Hospital, 2Department of Gynecology and Obstetrics, Queen Elizabeth Hospital, 3Department of Obstetrics and Gynecology, Queen Mary Hospital, The University of Hong Kong The present pilot study describes the development of laparoscopic non-mesh cerclage pectopexy to treat pelvic organ prolapse. The procedure can be used to prevent any complications associated with the use of mesh. Neuroscience Modulation of the Neurophysiological Response to Fearful and Stressful Stimuli Through Repetitive Religious Chanting Hin Hung Sik1, Georgios T. Halkias1, Chunqi Chang2, Junling Gao1, Hang Kin Leung1, Bonnie Wai Yan Wu1 1Buddhism and Science Research Lab, Centre of Buddhist Studies, The University of Hong Kong, 2School of Biomedical Engineering, Shenzhen University The present event-related potential (ERP) study provides a unique protocol for investigating how religious chanting can modulate negative emotions. The results demonstrate that the late positive potential (LPP) is a robust neurophysiological response to negative emotional stimuli and can be effectively modulated by repetitive religious chanting. Biology Visualization and Quantification of Brown and Beige Adipose Tissues in Mice using [18F]FDG Micro-PET/MR Imaging Qing Liu*1,2, Kel Vin Tan*3, Hing-Chiu Chang3, Pek-Lan Khong3, Xiaoyan Hui1,2,4 1State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, 2Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 3Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 4School of Biomedical Sciences, Institute of Vascular Medicine, Chinese University of Hong Kong Functional imaging and quantitation of thermogenic adipose depots in mice using a micro-PET/MR imaging-based approach. Medicine Intratracheal Administration of Dry Powder Formulation in Mice Yingshan Qiu1, Qiuying Liao1, Michael Y.T. Chow1,2, Jenny K.W. Lam1 1Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, 2Advanced Drug Delivery Group, Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented. Medicine Establishing a Swine Model of Post-myocardial Infarction Heart Failure for Stem Cell Treatment Sijia Sun*1, Yu Jiang*1, Zhe Zhen1,2, Wing-Hon Lai1,2, Songyan Liao1,2, Hung-Fat Tse1,2 1Cardiology Division, Department of Medicine, Queen Mary Hospital, University of Hong Kong, 2Shenzhen Institutes of Research and Innovation, University of Hong Kong We sought to establish a swine model of heart failure induced by left circumflex artery blockage and rapid pacing to test the effect and safety of intramyocardial administration of stem cells for cell-based therapies. Chemistry Asymmetric Thermoelectrochemical Cell for Harvesting Low-grade Heat under Isothermal Operation Kaiyu Mu*1, Xun Wang*1, Ka Ho Li1, Yu-Ting Huang1, Shien-Ping Feng1 1Electrochemical Nanoengineering Group, Department of Mechanical Engineering, University of Hong Kong Low-grade heat is abundant, but its efficient recovery is still a great challenge. We report an asymmetric thermoelectrochemical cell using graphene oxide as a cathode and polyaniline as an anode with KCl as the electrolyte. This cell works under isothermal heating, exhibiting a high heat-to-electricity conversion efficiency in low-temperature regions. Biology Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues Daniels Konja1, Cuiting Luo1, Wai Yan Sun1, Kangmin Yang1, Andy W.C. Man1, Aimin Xu1, Paul M. Vanhoutte1, Yu Wang1 1The State Key Laboratory of Pharmaceutical Biotechnology and the Department of Pharmacology and Pharmacy, University of Hong Kong The protocol describes the use of wire myography to evaluate the transmural isometric tension of mesenteric arteries isolated from mice, with special consideration of the modulation by factors released from endothelial cells and perivascular adipose tissues. Behavior A Behavioral Test Battery for the Repeated Assessment of Motor Skills, Mood, and Cognition in Mice Ran You1,2,3, Yan Liu3, Raymond Chuen-Chung Chang3 1 A comprehensive behavioral test battery of motor skills, mood—including social interaction, depression, and anxiety—and cognition is designed for the repeated assessment of neurodegeneration-related behavioral changes in mice. Neuroscience Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies Xue Deng1, Lai-Heung Phoebe Chau2, Suk-Yee Chiu2, Kwok-Pui Leung3, Yong Hu1, Wing-Yuk Ip1 1Department of Orthopedics & Traumatology, The University of Hong Kong, 2Clinical Electro-diagnostic Unit, Tung Wah Hospital, 3Department of Medicine, The University of Hong Kong Here we present a protocol using nerve conduction studies and ultrasound to screen potential axonal degeneration associated with carpal tunnel syndrome. The criteria for differentiation are established. Compared to conventional approaches, this method is noninvasive, convenient, and efficient, with an overall satisfactory accuracy, sensitivity, and specificity. Developmental Biology A Familial Hypercholesterolemia Human Liver Chimeric Mouse Model Using Induced Pluripotent Stem Cell-derived Hepatocytes Jiayin Yang*1,2,6, Lai-Yung Wong*2, Xiao-Yu Tian*3, Rui Wei1,2, Wing-Hon Lai2, Ka-Wing Au2, Zhiwei Luo4,5, Carl Ward4,5, Wai-In Ho2, David P. Ibañez4,5, Hao Liu4,5, Xichen Bao4,5, Baoming Qin4,5, Yu Huang3, Miguel A. Esteban4,5,7, Hung-Fat Tse1,2,6,7 1Department of Medicine, University of Hong Kong-Shenzhen Hospital, 2The Cardiology Division, Department of Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, 3School of Biomedical Sciences, Institute of Vascular Medicine, Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, 4Key Laboratory of Regenerative Biology of the Chinese Academy of Sciences, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health and Guangzhou Medical University, 5Laboratory of RNA, Chromatin, and Human Disease, CAS Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 6Research Centre of Heart, Brain, Hormone, and Healthy Ageing, Li Ka Shing Faculty of Medicine, University of Hong Kong, 7Hong Kong-Guangdong Stem Cell and Regenerative Medicine Research Centre, University of Hong Kong and Guangzhou Institutes of Biomedicine and Health Here, we present a protocol to generate a human liver chimeric mouse model of familial hypercholesterolemia using human induced pluripotent stem cell-derived hepatocytes. This is a valuable model for testing new therapies for hypercholesterolemia. Engineering Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy (ATOM) Anson H. L. Tang1, Queenie T. K. Lai1, Bob M. F. Chung2, Kelvin C. M. Lee1, Aaron T. Y. Mok1, G. K. Yip1, Anderson H. C. Shum2, Kenneth K. Y. Wong1, Kevin K. Tsia1 1Department of Electrical and Electronic Engineering, The University of Hong Kong, 2Department of Mechanical Engineering, The University of Hong Kong This protocol describes the implementation of an asymmetric-detection time-stretch optical microscopy system for single-cell imaging in ultrafast microfluidic flow and its applications in imaging flow cytometry. Engineering Scalable Solution-processed Fabrication Strategy for High-performance, Flexible, Transparent Electrodes with Embedded Metal Mesh Arshad Khan1, Sangeon Lee2, Taehee Jang3, Ze Xiong4, Cuiping Zhang1,5, Jinyao Tang4, L. Jay Guo2,3, Wen-Di Li1,5 1Department of Mechanical Engineering, University of Hong Kong, 2Department of Mechanical Engineering, University of Michigan, 3Department of Electrical Engineering and Computer Science, University of Michigan, 4Department of Chemistry, University of Hong Kong, 5HKU-Shenzhen Institute of Research and Innovation This protocol describes a solution-based fabrication strategy for high-performance, flexible, transparent electrodes with fully-embedded, thick metal mesh. Flexible transparent electrodes fabricated by this process demonstrate among the highest reported performances, including ultra-low sheet resistance, high optical transmittance, mechanical stability under bending, strong substrate adhesion, surface smoothness, and environmental stability. Developmental Biology Hypoxic Preconditioning of Marrow-derived Progenitor Cells As a Source for the Generation of Mature Schwann Cells Yat-Ping Tsui*1, Alan Kwan-Long Mung*1, Ying-Shing Chan1, Daisy Kwok-Yan Shum1, Graham Ka-Hon Shea2 1School of Biomedical Sciences, The University of Hong Kong, 2Department of Orthopaedics and Traumatology, The University of Hong Kong Marrow stromal cells (MSCs) with neural potential exist within the bone marrow. Our protocol enriches this population of cells via hypoxic preconditioning and thereafter directs them to become mature Schwann cells. Behavior Using Wavelet Entropy to Demonstrate how Mindfulness Practice Increases Coordination between Irregular Cerebral and Cardiac Activities Hin Hung Sik1, Junling Gao1,2, Jicong Fan1, Bonnie Wai Yan Wu1, Hang Kin Leung1, Yeung Sam Hung2 1Centre of Buddhist Studies, The University of Hong Kong, 2Department of Electrical and Electronic Engineering, The University of Hong Kong This manuscript describes how to use the wavelet entropy index to analyze high-density electroencephalography (EEG) and electrocardiography (ECG) data. We show that the irregularity of cerebral and cardiac activities became more coordinated during mindfulness-based stress reduction practice. Medicine Minimally Invasive Transverse Aortic Constriction in Mice Aung Moe Zaw1, Connor M. Williams2, Helen K. W. Law3, Billy Kwok Chong Chow1 1School of Biological Sciences, The University of Hong Kong, 2College of Arts and Science, New York University, 3Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University Minimally invasive transverse aortic constriction (MTAC) conserves the essentials of regular transverse aortic constriction (TAC) while eliminating the use of a ventilator with tracheal intubation. It proves to be a highly desirable method for high-throughput studies on left ventricular overload, particularly in translational studies. Biology Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm Vera B. S. Chan1, Takashi Toyofuku2, George Wetzel3, Laxmikant Saraf3, Vengatesen Thiyagarajan4, Andrew S. Mount1 1Department of Biological Sciences, Clemson University, 2Department of Marine Biodiversity Research (BioDive), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 3Advanced Material Research Laboratory (AMRL), Clemson University, 4Swire Institute of Marine Sciences and School of Biological Sciences, The University of Hong Kong We demonstrate the use of various microscopy methods that are useful in observing the calcification of a tubeworm, Hydroides elegans, as well as locating and characterizing the first calcified material. Live microscopy and electron microscopy are used together to provide functional and material information that are important in studying biomineralization. Bioengineering Modeling Ovarian Cancer Multicellular Spheroid Behavior in a Dynamic 3D Peritoneal Microdevice Shan-Shan Li*1, Carman K. M. Ip*1, Matthew Y. H. Tang*2, Samuel K. H. Sy2, Susan Yung3, Tak-Mao Chan3, Mengsu Yang4, Ho Cheung Shum2, Alice S.T. Wong1 1School of Biological Sciences, University of Hong Kong, 2Department of Mechanical Engineering, University of Hong Kong, 3Department of Medicine, University of Hong Kong, 4Department of Biomedical Sciences, Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institutes of City University of Hong Kong To study ovarian tumor progression in a physiologically relevant model, multicellular spheroids were cultured in a microdevice under simulated fluid flow. This dynamic 3D model emulates the intraperitoneal environment with the cellular and mechanical components where ovarian cancer metastasis occurs. Bioengineering Construction of Defined Human Engineered Cardiac Tissues to Study Mechanisms of Cardiac Cell Therapy Timothy J. Cashman1, Rebecca Josowitz2, Bruce D. Gelb2, Ronald A. Li1,3, Nicole C. Dubois2, Kevin D. Costa1 1Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, 2The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, 3Stem Cell & Regenerative Medicine Consortium, LKS Faculty of Medicine, University of Hong Kong This manuscript describes the creation of defined engineered cardiac tissues using surface marker expression and cell sorting. The defined tissues can then be used in a multi-tissue bioreactor to investigate mechanisms of cardiac cell therapy in order to provide a functional, yet controlled, model system of the human heart. Biology High Efficiency Differentiation of Human Pluripotent Stem Cells to Cardiomyocytes and Characterization by Flow Cytometry Subarna Bhattacharya*1, Paul W. Burridge*2, Erin M. Kropp1, Sandra L. Chuppa1, Wai-Meng Kwok3, Joseph C. Wu2, Kenneth R. Boheler4,5, Rebekah L. Gundry1,6 1Department of Biochemistry, Medical College of Wisconsin, 2Stanford Cardiovascular Institute, Stanford University School of Medicine, 3Department of Anesthesiology, Medical College of Wisconsin, 4Stem Cell and Regenerative Medicine Consortium, LKS Faculty of Medicine, Hong Kong University, 5Division of Cardiology, Johns Hopkins University School of Medicine, 6Cardiovascular Research Center, Biotechnology and Bioengineering Center, Medical College of Wisconsin The article describes the detailed methodology to efficiently differentiate human pluripotent stem cells into cardiomyocytes by selectively modulating the Wnt pathway, followed by flow cytometry analysis of reference markers to assess homogeneity and identity of the population. Neuroscience Morphometric Analyses of Retinal Sections Tin Fung Chan1, Kin Chiu1, Carmen Ka Ming Lok1, Wing Lau Ho1, Kwok-Fai So1,2,3, Raymond Chuen-Chung Chang1,2,3 1Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong, 2Research Centre of Heart, Brain, Hormone and Healthy Aging, LKS Faculty of Medicine, The University of Hong Kong, 3State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong This video demonstrates three types of morphometric analyses of the retina, which include measuring the inner nuclear layer thickness, quantifying the number of retinal ganglion cells (RGCs) and measuring the sizes of RGCs. The technique can offer a simple but scientific platform for morphometric analyses. Biology Retrograde Labeling of Retinal Ganglion Cells by Application of Fluoro-Gold on the Surface of Superior Colliculus Kin Chiu1, Wui-Man Lau1, Sze-chun Yeung1, Raymond Chuen-Chung Chang1, Kwok-Fai So1 1The University of Hong Kong - HKU This video describes the method of retrograde labeling of RGC by applying fluoro-gold (FG) on the surface of superior colliculus (SC). Technique involves drilling the skull, aspirating the cortex, and applying gelatin sponge over entire dorsal surface of SC. Biology Laser-Induced Chronic Ocular Hypertension Model on SD Rats Kin Chiu1, Raymond Chang1, Kwok-Fai So1 1Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong - HKU Glaucoma is one of the major causes of blindness in the world. Elevated intraocular pressure is a major risk factor. Laser photocoagulation induced ocular hypertension is one of the well established animal models. This video demonstrates how to induce ocular hypertension by Argon laser photocoagulation in rat. Biology Intravitreous Injection for Establishing Ocular Diseases Model Kin Chiu1, Raymond Chuen-Chung Chang1, Kwok-Fai So1 1The University of Hong Kong - HKU Intravitreous injection is a widely used technique in visual sciences research for ocular diseases or as direct application of local treatment. This video demonstrated a protocol for intravitreous injection using a 1ml syringe with glass pipette. Useful tips about avoiding massive bleeding and lens damage are given. Biology Micro-dissection of Rat Brain for RNA or Protein Extraction from Specific Brain Region Kin Chiu1, Wui Man Lau1, Ho Tak Lau1, Kwok-Fai So1, Raymond Chuen-Chung Chang1 1Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong - HKU Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates micro-dissection of four major brain regions include olfactory bulb, frontal cortex, striatum and hippocampus in fresh rat brain tissue. Useful tips for quick removal of respective regions to avoid RNA and protein degradation of the tissue are given.