Image source @ Visual China
Text | Observe the future of technology
Human resurrection technology is a very futuristic concept, of course, so far, human resurrection also only exists in science fiction works, that is, the reduction of body functions to a state of deep stagnation, stop aging, and then wake up when needed. Among them, cryonics technology is the best "resurrection" method at present, that is, to freeze the body without vital signs, hoping to be resurrected in the future when medicine is highly developed with the progress of science.
In 1985, refrigeration technology was introduced, which opened the "materialization of life". Nowadays, with the development of cryonics technology, human beings have boldly carried out experiments on cryonics, and people have been able to vaguely see the tomorrow of cryonics, but with them, there are ethical questions that cannot be ignored, and ancient prophecies about "eternal life".
Cryonics today
In fact, freezing technology seems distant, but it has been applied to the current society, that is, the freezing of sperm, eggs and embryos.
Sperm freezing only requires the collection of sufficient semen, take a small amount for sampling, add a protective agent, and save it in liquid nitrogen at minus 196 degrees Celsius, because all metabolism and molecular movement inside the sperm are stopped in the low temperature liquid nitrogen environment. In fact, people also use the same method to store food in refrigerators and cold storage,
When needed to be used, the sample tube storing sperm is immersed in tap water or double steamed water at room temperature or simply exposed to air for thawing, of which the protective agent is added to prevent the water in the sperm cells from freezing, and the volume increases and breaks the cell membrane.
Egg freezing is relatively complicated, unlike semen, women need to take ovulation induction drugs before egg retrieval, so that multiple follicles develop in advance, using puncture techniques to release multiple eggs, so that multiple eggs can be obtained at once. Frozen eggs also need to be kept in ultra-low temperature liquid nitrogen.
At present, egg freezing technology is gradually developing, initially slow freezing, and now it is possible to quickly freeze. Flash freezing is also called vitrification freezing, this method can make the protective liquid drop to minus 196 ° C in a short period of time and appear vitreous, which can better avoid egg cells in the freezing process to produce ice crystals and be damaged. However, despite this, the egg freezing technology is still immature compared to the more mature sperm freezing and embryo freezing techniques.
In addition to the freezing of sperm and eggs, embryo freezing is also one of the most important freezing technologies at present. Embryo freezing technology, which has been applied since 1980, has become a routine method of preserving fertility in current clinical treatment, effectively reducing the repeated hormonal stimulation of patients undergoing hyperovulation induction therapy. In 2005, the American Council on Reproductive Medicine Ethics issued fertility preservation guidelines for cancer patients, which stipulate that embryo freezing techniques are the only approved method of fertility preservation, and other laboratory techniques such as oocyte freezing or ovarian tissue freezing need to be completed under the supervision of an ethics body review committee.
Of course, whether it is sperm, eggs or embryos, it is still only biological freezing at the molecular level, in addition to cell freezing, tissue freezing is now a reality. Among them, ovarian tissue freezing is more complex and difficult than embryonic and oocyte freezing. However, the advantage of ovarian tissue freezing is that it does not require drug stimulation and sperm, and is the best choice for patients with prepubertal malignancies.
Ovarian tissue can be frozen by laparoscopic or open abdominal removal, avoiding uncertainties of ovarian stimulation. After cryo-resuscitation of the ovarian cortex, the survival rate of the basal follicle can reach about 65%, and the recovered ovarian tissue can be transplanted in situ or ectopic to restore the patient's endocrine function or ovulation function.
Tissue freezing is one more step forward, and it's human freezing. Cryonics technology, i.e. cryogenic storage of the bodies of humans or other animals. As mentioned earlier, under low temperature conditions, the rate of metabolism and biodegradation of the human body will also be reduced, and it is this basic law that human freezing can be made possible step by step.
However, from cell freezing to tissue freezing to cryonics, the main problem with this technology is that during the freezing process, the formation of ice destroys the cells in the body. Therefore, for cryonics, "vitrification" becomes an important step in the cryonics program, the purpose of which is to ensure that freezing does not lead to the formation of products. Specifically, before freezing, the body's blood is released and most of the body fluids are replaced with cryoprotective mixtures that prevent freezing. Of course, this still needs to face many technical problems.
People who "eat crabs"
Although the application of cryonics technology is very rare at present, the first people in the world to "eat crabs" and more people who dare to try.
James Bedford, a professor of psychology at the University of California and founder of the Biofreken Foundation, was the world's first cryoprefrom who was frozen after he died of kidney cancer in 1967 and is still in the United States, the Alcor Life Extension Foundation.
In the mainland, in 2015, Chongqing female writer Du Mou also underwent surgery from the Alcor Life Extension Foundation to freeze her brain. After that, Zhan X in Shandong became the second Chinese to accept cryonics technology, but unlike Du X, Zhan X accepted full body freezing. Zhan Moumou died of lung cancer in Jinan on May 8, 2017, and she did not return to dust like most people, but immediately underwent cryosurgery and "slept" in a liquid nitrogen tank with a volume of 2,000 liters and a temperature of -196 ° C. Zhan moumou became the first "patient" frozen and waiting for resurrection in China and the first Chinese whose whole body was cryopreserved.
In February 2018, a South Korean man in his fifties also froze his eighties-something mother who had died of blood cancer — the first South Korean to apply for the Frozen Person Service. The man approached KrioAsia, a partner company of the Russian cryonics company KrioRus. As soon as his mother died, he was initially frozen and then sent to a freezer in Moscow, Russia, for a shelf life of one hundred years.
At present, representative companies that preserve cryoprexes include the Alko Foundation for the Continuation of Life in the United States, the Cryonics Institute and KrioRus in Russia. Among them, although the Alcor Life Extension Foundation and the Cryonics Institute in the United States have not released accurate data, an estimated 600 people around the world have been frozen. Moreover, more people have signed consent forms and are ready to start freezing procedures. In fact, in recent years, the number of people who want to freeze has been increasing, etc.
At present, most of the people frozen by cryopreservation technology are patients with terminal illnesses such as cancer, people who die early, or people who have suffered major accidents and their bodies have been damaged beyond resuscitation. People can choose to freeze only the head or brain, or they can choose to freeze only the body, which also determines the level of the cost, ranging from $10,000 to $250,000.
In addition, each business saves cryostats differently. In simple terms, companies inject anticoagulants, antioxidants, tranquilizers and other drugs after the deceased is declared dead to prevent blood clotting, brain damage, and activate circulatory systems such as artificial lung respiration. Companies will quickly freeze the human body within 24 hours of the deceased's death, draw all the blood from the deceased's body, inject a blood substitute (preservation solution). Since the function of the human brain begins to decline 30 seconds after death, cryonics must be performed at a very fast rate.
In recent decades, the technology of completely freezing the body has been scientifically proven and commercialized. However, the current stage of thawing technology is not yet perfect – today, there is no technology that can wake up frozen people, which makes cryonics largely risky. However, academia predicts that by around 2040, humans will be able to recover the brains of frozen dead people and transplant them into artificial bodies. But how to restore the brain's memory has become a difficult problem.
Contrary to the laws of life
Since ancient times and today, people have been pursuing eternal life.
Before that, Qin Shi Huang built a lot of civil engineering, superstitiously believed in the art of immortality, and even spent thousands of dollars to send Xu Fu and five hundred pairs of virgin boys and girls overseas to seek immortal medicine. Later, Emperor Wu of Han sent people to ask for immortals and medicines, and built a high platform to undertake the so-called xianlu.
Beniamain Franklin also expressed his desire for eternal life in a letter to Jacques Dubourg in 1773: "How I wished I could immerse my body in a way that would be sealed and allowed to pass until one day in the future I was awakened and continued to live." Because, seeing what america will look like 100 years later is my life's wish. I want to die in the ordinary way, and with some friends, be soaked in wooden barrels containing madeira's white wine, wait a hundred years, and then bathe in the warm sun again and be reborn in my beloved America. ”
For those who aspire to eternal life, the "resurrection" of cryonics undoubtedly shows great appeal. Max Mohr, a believer in the transhumanist movement, even argues that the current funeral is a tragedy in the case of cryonics.
Max Mohr thinks that when we look back 50 or 100 years from now, we will shake our heads and sigh: "What were people thinking at that time?" Those who were sent to an incinerator or buried in the earth were near-normal, but some individuals who were slightly dysfunctional. By now, these people will be stored at low temperatures. ”
But the question that has to be considered is, if cryonics can be successful, what will this choice that violates the laws of life and death of nature bring to human beings?
On the one hand, people who oppose radical life-extension technologies often say that without death, the meaning of life ceases to exist. They also argue that postponing death into the distant future or eliminating it altogether can have devastating psychological consequences. Based on this, in the face of future or future cryonics, perhaps changing the perception of death is the first step in making a choice.
At present, it is believed that these people who are stored at low temperatures have legally died, but in the future, physical death may not be equal to real death, and real death will become theoretical death, that is, the information in the human brain is destroyed, and the original body theoretically loses the possibility of recovery. But the irony is that it is precisely because of this difference that cryonics has become a meaningful and legal measure. Cryonics is not considered a medical item, so an individual must be legally declared dead before freezing can be performed.
On the other hand, in the face of a future of longer lifespans or "human resurrection", a real problem that must be considered is the problem related to demographics. Assuming that we cannot exist apart from the Earth, then, in order to avoid falling into the Malthusian Trap, society may need to control the population below a fixed value. Of course, the magnitude of this value may depend on the level of various future technologies, such as the yield of grain.
When Jose Cordeiro of the United Nations Forum for the Future founded the Cryopreservation Society in Spain, he was opposed not only by religious figures, but also by legal and institutional opposition from the government. However, Max More, chairman of the Alcor Life Extension Foundation, said, "Nevertheless, cryopreservation technology will continue to evolve and spread around the world." Before cryonics technology spreads around the world, there is clearly a lot of room for discussion.