For immediate release: 29 July 2019
Okayama University research: Prosthetics for Retinal Stimulation
(Okayama, 29 July) In a study recently published in Advanced Biomedical Engineering, researchers at Okayama University report a thin photoelectric film which can stimulate degenerated retinal tissues of the eye.
Using electric signals to stimulate tissues is the basis of several medical devices such as pacemakers for the heart or neurostimulators used for patients suffering from epileptic fits. A research team led by Dr. MATSUO toshihiko at Okayama University has developed OURePTM, a photoelectric dye-coupled thin film device that generates electric potential changes when exposed to light. In their latest study, the research team reveals the ability of this device in stimulating degenerated retinal tissues.
OURePTM is generated by placing polyethylene, a polymer, between two aluminum plates. When the polymer is melted, and a high pressure applied subsequently, a fine polyethylene film is created. The film then undergoes a chemical reaction wherein it is coupled to a photoelectric dye.
The researchers first placed the photoelectric dye-coupled film on the electric potential-measuring device and exposed it to flashing light. As expected, waves of electric signals were observed on the film surface when light hit the film. To then test the ability of this film in stimulating nervous tissue, retinal tissues of rats with retinal dystrophy, a retinal degenerative disorder, were procured. When the retinal tissues of healthy rats were brought to close contact with a multielectrode array, a device used to measure electrical signals from biological tissues, and exposed to light, corresponding waves of electric signals were observed. However, no such signals were observed with the dystrophic retinal tissue. The photoelectric dye-coupled film was then placed on top of the dystrophic tissues which resulted in the induction of electric signals in response to bouts of light. A control film, without the photoelectric dye did not induce electric signals in these tissues.
To measure these electric signals more precisely, a nylon mesh was used to keep the dystrophic tissues and the multielectrode array detector in closer contact. This proximity revealed background electric impulses of weak amplitude with the dystrophic retinal tissues alone. In the background of weak amplitude of these signals, light induced remarkable action potential spikes in the dystrophic retinal tissues, in the presence of the photoelectric dye-coupled film. The photoelectric dye-coupled film was thus instrumental in boosting electrical impulses within the degenerated retina.
“The current study provides direct evidence for the ability of the photoelectric dye-coupled polyethylene film to elicit electroretinogram-like response and action potential spikes in degenerative retina,” conclude the researchers. Retinitis pigmentosa, is one such condition, wherein photoreceptors of the eye slowly die, leading to blindness. This study revealed the prosthetic value of OURePTM in potentially replacing the lost photosensitivity of these cells. Implanting the device and testing visual enhancement in animals in their preceding studies have already given further insights.
Background
Photoelectric dye: A photoelectric dye is an organic molecule that can absorb light and emit electric signals. The dye thus converts light energy into electrical energy. When these dye molecules are coupled to the surface of biological safe polymers such as polyethylene, they can be implanted onto tissue surfaces and used for their electrical impulse-generating properties to stimulate the surrounding tissues.
Reference
Toshihiko Matsuo, Mikako Sakurai, Keiko Terada, Tetsuya Uchida, Koichiro Yamashita, Tenu Tanaka, Kenichi Takarabe. Photoelectric Dye-Coupled Polyethylene Film: Photoresponsive Properties Evaluated by Kelvin Probe and In Vitro Biological Response Detected in Dystrophic Retinal Tissue of Rats. Advanced Biomedical Engineering, May 2019.
DOI : https://doi.org/10.14326/abe.8.137
https://www.jstage.jst.go.jp/article/abe/8/0/8_8_137/_article/-char/en
Reference (Okayama Univ. e-Bulletin): Associate Professor MATSUO’s team
e-Bulletin Vol.8：Photoelectric dye-coupled thin film as a novel type of retinal prosthesis
OU-MRU Vol.8：Light-responsive dye stimulates sight in genetically blind patients
OU-MRU Vol.39：Successful test of retinal prosthesis implanted in rats
OU-MRU Vol.47：Candidate genes for eye misalignment identified
OU-MRU Vol.53：Successful implantation and testing of retinal prosthesis in monkey eyes with retinal degeneration
Further information
Okayama University
1-1-1 Tsushima-naka , Kita-ku , Okayama 700-8530, Japan
Public Relations Division
E-mail: www-adm (a) adm.okayama-u.ac.jp
For inquiries, please contact us by replacing (a) with the @ mark.
Website: www.okayama-u.ac.jp/index_e.html
Okayama Univ. e-Bulletin: www.okayama-u.ac.jp/user/kouhou/ebulletin/
About Okayama University (You Tube): https://www.youtube.com/watch?v=iDL1coqPRYI
Okayama University Image Movie (You Tube): https://www.youtube.com/watch?v=KU3hOIXS5kk
Correspondence to
Associate Professor MATSUO toshihiko, M.D., Ph.D.
Ophthalmology, Okayama University Medical School and
Graduate School of Interdisciplinary Science and Engineering
in Health Systems,
2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
Okayama University Medical Research Updates （OU-MRU）
The whole volume : OU-MRU (1- )
Vol.1：Innovative non-invasive ‘liquid biopsy’ method to capture circulating tumor cells from blood samples for genetic testing
Vol.2：Ensuring a cool recovery from cardiac arrest
Vol.3：Organ regeneration research leaps forward
Vol.4：Cardiac mechanosensitive integrator
Vol.5：Cell injections get to the heart of congenital defects
Vol.6：Fourth key molecule identified in bone development
Vol.7：Anticancer virus solution provides an alternative to surgery
Vol.8：Light-responsive dye stimulates sight in genetically blind patients
Vol.9：Diabetes drug helps towards immunity against cancer
Vol.10：Enzyme-inhibitors treat drug-resistant epilepsy
Vol.11：Compound-protein combination shows promise for arthritis treatment
Vol.12：Molecular features of the circadian clock system in fruit flies
Vol.13：Peptide directs artificial tissue growth
Vol.14：Simplified boron compound may treat brain tumours
Vol.15：Metamaterial absorbers for infrared inspection technologies
Vol.16：Epigenetics research traces how crickets restore lost limbs
Vol.17：Cell research shows pathway for suppressing hepatitis B virus
Vol.18：Therapeutic protein targets liver disease
Vol.19：Study links signalling protein to osteoarthritis
Vol.20：Lack of enzyme promotes fatty liver disease in thin patients
Vol.21：Combined gene transduction and light therapy targets gastric cancer
Vol.22：Medical supportive device for hemodialysis catheter puncture
Vol.23：Development of low cost oral inactivated vaccines for dysentery
Vol.24：Sticky molecules to tackle obesity and diabetes
Vol.25：Self-administered aroma foot massage may reduce symptoms of anxiety
Vol.26：Protein for preventing heart failure
Vol.27：Keeping cells in shape to fight sepsis
Vol.28：Viral-based therapy for bone cancer
Vol.29：Photoreactive compound allows protein synthesis control with light
Vol.30：Cancer stem cells’ role in tumor growth revealed
Vol.31：Prevention of RNA virus replication
Vol.32：Enzyme target for slowing bladder cancer invasion
Vol.33：Attacking tumors from the inside
Vol.34：Novel mouse model for studying pancreatic cancer
Vol.35：Potential cause of Lafora disease revealed
Vol.36：Overloading of protein localization triggers cellular defects
Vol.37：Protein dosage compensation mechanism unravelled
Vol.38：Bioengineered tooth restoration in a large mammal
Vol.39：Successful test of retinal prosthesis implanted in rats
Vol.40：Antibodies prolong seizure latency in epileptic mice
Vol.41：Inorganic biomaterials for soft-tissue adhesion
Vol.42：Potential drug for treating chronic pain with few side effects
Vol.43：Potential origin of cancer-associated cells revealed
Vol.44：Protection from plant extracts
Vol.45：Link between biological-clock disturbance and brain dysfunction uncovered
Vol.46：New method for suppressing lung cancer oncogene
Vol.47：Candidate genes for eye misalignment identified
Vol.48：Nanotechnology-based approach to cancer virotherapy
Vol.49：Cell membrane as material for bone formation
Vol.50：Iron removal as a potential cancer therapy
Vol.51：Potential of 3D nanoenvironments for experimental cancer
Vol.52：A protein found on the surface of cells plays an integral role in tumor growth and sustenance
Vol.53：Successful implantation and testing of retinal prosthesis in monkey eyes with retinal degeneration
Vol.54：Measuring ion concentration in solutions for clinical and environmental research
Vol.55：Diabetic kidney disease: new biomarkers improve the prediction of the renal prognosis
Vol.56：New device for assisting accurate hemodialysis catheter placement
Vol.57：Possible link between excess chewing muscle activity and dental disease
Vol.58：Insights into mechanisms governing the resistance to the anti-cancer medication cetuximab
Vol.59：Role of commensal flora in periodontal immune response investigated
Vol.60：Role of commensal microbiota in bone remodeling
Vol.61：Mechanical stress affects normal bone development
Vol.62：3D tissue model offers insights into treating pancreatic cancer
Vol.63：Promising biomarker for vascular disease relapse revealed
Vol.64：Inflammation in the brain enhances the side-effects of hypnotic medication
Vol.65：Game changer: How do bacteria play Tag ?
Vol.66：Is too much protein a bad thing?
Vol.67：Technology to rapidly detect cancer markers for cancer diagnosis
Vol.68：Improving the diagnosis of pancreatic cancer
Vol.69：Early gastric cancer endoscopic diagnosis system using artificial intelligence
0 件のコメント:
コメントを投稿