Congratulations to 21st Century Medicine!!

john grigg (
Thu, 23 Sep 1999 12:59:21 PDT

Hello everyone,

I looked over the patent for 21st Century Medicine's research developments and must say I am VERY IMPRESSED!!! I congratulate those who made it possible!!

>From the patent document:

                             FINAL COOLING RATE
    ORGAN   (AT C.)
                             (AT C.)
    Kidney C./min.
    Liver C./min.
    Brain C./min.
    Body C./min.

The cooling rates shown in Table III are more than ten times greater than can be achieved by previous external cooling methods. Such rapid cooling will allow significant decreases in the concentration of cryoprotectants needed to vitrify, enhancing the prospects for successful cryopreservation of organs with non-toxic CPA mixtures. These cooling rates also for the first time open the possibility of vitrifying whole humans.

(Later at the conclusion)

The method of the present invention allows cooling and subsequent rewarming from temperatures lower than C. at rates exceeding C. per minute for some organs. These rates are much higher than can be achieved by external heat transfer methods, and will allow significant reduction of the concentration of cryoprotective agents needed to achieve reversible vitrification of organs for long-term banking. Heat transfer by inert fluid perfusion is also beneficial for reducing ice crystal damage and cryoprotectant toxicity during ordinary freezing and thawing.

The present invention also provides a class of new cryoprotective agent (glycol ethers) for reduction and prevention of ice formation during cooling of vascular tissues and organs. Glycol ethers generally, and methoxylated compounds in particular, are highly penetrating agents that equilibrate rapidly upon perfusion, and exhibit strong ice inhibition and glass forming properties. The low viscosity and freezing point of these compounds also make them well-suited for sub-zero perfusion to minimize toxic effects. Toxicities are compatible with the potential use of glycol ethers in perfusate solutions for reversible cryopreservation of organs and large organisms by freezing or vitrification.

(End of patent document reproduction)

That cooling rates using these techniques are TEN times faster then in the past is incredible. And that glycol ethers are far superior penetrating agents compared to what was used in the past is a major step forward.

"These cooling rates also for the first time open the possibility of vitrifying whole humans" is a statement in the patent document that made me wonder when will these new methods in their entirety be used to TRULY vitrify a human??

And with such a combination of major advances what still needs to be done?? How could things still be improved? What are the possibilities down the road? What is next for 21st Century Medicine? And how is the Prometheus Project doing?

I hope the major cryonics providers will all adopt these methods for their clients. Is 21st Century Medicine working with the various organizations to bring them up to speed? Just how expensive will it be to offer these techniques??

I remember reading in the Cryocare archives a paper by Mike Darwin where he admitted the major damage suspension did on the cellular level and how so much still had to be done. Reading his paper took away much of my early hope in cryonics and a desire that breakthroughs would be made.

But having read through the patent I feel new hope!! Again my congratulations and thanks to all those who made it possible!! I want to hug them all!!

I look forward to hearing from you all regarding this patent and my views and questions about it.


John Grigg

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