Tokyo Medical and Dental University

5 ARTICLES PUBLISHED IN JoVE

Genetics

Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning

Takatoshi Murata¹, Ayako Okada¹, Khairul Matin^1,2,3, Nobuhiro Hanada¹

¹Department of Translational Research, Tsurumi University School of Dental Medicine, ²Endowed Department of International Oral Health Science (affiliated with Department of Translational Research), Tsurumi University School of Dental Medicine, ³Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University

We describe a facile, rapid, and relatively inexpensive method for the generation of gene-disrupted Streptococcus mutans strains; this technique may be adapted for the generation of gene-disrupted strains of various species.

Medicine

Electrophysiological Assessment of Murine Atria with High-Resolution Optical Mapping

Kensuke Ihara^*1, Koji Sugiyama^*1, Kentaro Takahashi^*1, Masahiro Yamazoe¹, Tetsuo Sasano², Tetsushi Furukawa¹

¹Department of Bio-informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, ²Department of Biofunctional Informatics, Tokyo Medical and Dental University

This protocol describes the electrophysiological evaluation of murine atria utilizing an optical mapping system with a high temporal and spatial resolution, including dual recordings of the membrane voltage and Ca²⁺ transient under programmed stimulation through a specialized electrode catheter.

Medicine

Piezo-ICSI for Human Oocytes

Kenichiro Hiraoka^1,2,3, Manami Isuge¹, Yuko Kamada¹, Tetsuya Kaji¹, Takako Suhara¹, Akira Kuga², Kumi Ohuchi¹, Masaru Hayashi¹, Kiyotaka Kawai^1,2,3

¹Kameda Medical Center, ²Kameda IVF Clinic Makuhari, ³Tokyo Medical and Dental University

Here, we describe a protocol for intracytoplasmic sperm injection into human oocytes using a piezo-driven micropipette.

Biology

Dissection of the Endolymphatic Sac from Mice

Keiji Honda^*1,2, Hyun Jae Lee^*1, Andrew J. Griffith^1,3, Isabelle Roux¹

¹Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, ²Department of Otorhinolaryngology, Tokyo Medical and Dental University, ³Department of Otolaryngology, College of Medicine, University of Tennessee Health Science Center

This study describes how to dissect the endolymphatic sac from the inner ear of the mouse at different ages. The result of a similar dissection is shown in an Slc26a4-null mouse model of enlargement of the endolymphatic sac. A transgenic mouse with a fluorescent reporter expressed in the endolymphatic sac is presented as a model to readily visualize the endolymphatic sac, and educational tool.

Biology

Integrated Bone Formation Through In Vivo Endochondral Ossification Using Mesenchymal Stem Cells

Shintaro Yamazaki^1,2, Yujing Lin³, Eriko Marukawa³, Masa-Aki Ikeda^1,3

¹Department of Molecular Craniofacial Embryology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, ²Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, ³Department of Regenerative and Reconstructive Dental Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University

Bone therapy via endochondral ossification by implanting artificial cartilage tissue produced from mesenchymal stem cells has the potential to circumvent the drawbacks of conventional therapies. Hyaluronic acid hydrogels are effective in scaling up uniformly differentiated cartilage grafts as well as creating integrated bone with vascularization between fused grafts in vivo.