Application plan
Using the fact that our gel can change in size intentionally, it would be useful material in various ways. Here, we will give two examples; the ability of moving cells around them and the application as a Vasoconstrictor.
A. Moving cells
It is known that the interaction between cells affect many things. Here, we will give 4 examples.
A-1. Development of embryo
The movements of cells in side the embryo are controlled by the interaction between cells. This movement is integral for things like implantation.
A-2. Maturation of B cells
B cells that make up the germinal center recognizes the antigen trapped in the Follicular dendritic cells(FDC), and matures by the interaction between helper T cells so that the class switch to IgA is induced.
A-3. Stripes of Zebrafish[1]
The stripes of zebrafish is known to be the result of the interaction of different pigment cells. For example, the difference between normal zebrafish stripes and jaguar mutant zebrafish is due to the alignment of pigment cells (Figure A-1).
If we can move cells at will, we can find the basic principles of how animals produce diverse patterns on their skin, and may be able to understand how animals evolved to acquire diverse patterns.
Figure A-1 Stripes of Zebrafish (Above: Normal zebrafish, Below: Jaguar Mutant)
A-4. Cause of diseases such as Dry Eye Syndrome[2]
T cells stick with old macrophages and interacts with it, releasing humoral factors, resulting in chronic inflammation (Figure A-2). This leads to a type of DES.
If we can control cells, we maybe able to stop old macrophages to interact with T cells, helping patients with DES.
Figure A-2 Dry Eye Syndrome mechanism
B. Application as a Vasoconstrictor[3]
Current Situation
Vasoconstrictors are used in many ways. In Japan, they are prescribed for migraine (a type of headache), treatment for hypotension, nasal congestions and inflamed eyes from allergies or colds.
However, there are many contraindication to vasoconstrictors. Medical history of myocardial infarction, ischemic heart disease (IHD), cerebrovascular disease, hypertension are just some of them. Liver dysfunction and thyroid abnormalities are also contraindication to some vasoconstrictors.
It is also added to local anesthetic to prevent poisoning from anesthetic, use less anesthetic and make them work longer and stronger. Because anesthetics have a vasodilation effect, when used on its own, anesthetics have a shorter duration of action and produce side effects due to local absorption of the drug.
However, this addition of the vasoconstrictor to the anesthetic has side effects. This is due to the medicinal action of the vasoconstrictor and results in symptoms such as tremor, dizziness, palpitation, tachycardia, headache, malaise, elevation of blood pressure, arrhythmia and coronary inefficiency.
Due to these side effects and the contraindication stated above, caution is needed when performing local anesthesia on patients with cardiovascular diseases.
For example, the amount of epinephrine used depends on the condition of the individual patient's heart.（http://www.showayakuhinkako.co.jp/medical/odt/odt02.pdf）
A vasoconstrictor, felypressin was thought not to stress the heart, but was found that they actually suppress the heart when the dosage becomes bigger. Therefore, we cannot say that felypressin is any safer than epinephrine.
We also have to use vasoconstrictors during local anesthesia.
Local anesthesia without vasoconstrictors used to be recommended. However, this turned out that it makes the patients’ blood pressure elevate more and had very weak anesthetic effect, so it is not done anymore.
How can we use our hydrogel as a vasoconstrictor?
If we put the hydrogel into our vessels and make them expand, we can narrow the flow just like a vasoconstrictor would do. In this way, we can "contract" our vessels without actually contracting it (Figure B-1).
If we use our hydrogel as a vasoconstrictor, this will change as follows.
After the usage of hydrogel vasoconstrictors, people who were contraindication to the usual vasoconstrictors (A lot!!) can enjoy their effects.
Anyone can be local anesthetized safely regardless of their medical conditions because the gel does not affect anywhere else than the targeted vessel.
Why is this important??
A lot of countries nowadays have an aging population. Furthermore, lifestyle diseases such as heart disease, strokes and atherosclerosis; which, of course, lead to diseases stated as contraindication to vasoconstrictors; are increasing. This means that more and more people would be contraindication to the usual vasoconstrictors. However, with this hydrogel derived vasoconstrictor, anyone can enjoy its benefits.
Figure B-1. Gel-Vasconstrictor
Reference
[1] https://resou.osaka-u.ac.jp/ja/research/2012/20120207_1 (viewed on 21st October 2018)
[2] http://kompas.hosp.keio.ac.jp/sp/contents/medical_info/science/201409.html (viewed on 21st October 2018)
[3] https://www.jmedj.co.jp/journal/paper/detail.php?id=3503 (viewed on 21st October 2018)