Acquaintance

When you think about the future, you assume that in the year 2100 you will find impressive technological achievements or adventures that can help you discover unimaginable things. There will certainly be talks about space missions that will be as close as, say, a trip to another continent or to another country, nothing special. However, in order to achieve a future in which people can travel beyond the Earth so easily, many considerations must be taken into account. One of the most important is the impact of this type of travel on human health. The phenomenon of cosmic anemia cannot be ignored.

During space missions, it has been recorded that astronauts are exposed to extreme microgravity and hypergravity conditions that cause changes in body functions. One of them is anemia — it has already been reported in the reports on the condition of astronauts when they returned from their travels. The causes are: hemolysis (Trudel et al, 2022), neocytolysis (Alfred et al, 1997) and changes in membrane composition (Rizzo et al, 2012).

A lot of research has been done in microgravity. But in hypergravity, there were significantly fewer of them. Hypergravity has been found to affect the stability of the cell membrane (Kiss et al, 2016). According to the hypothesis that the hypergravity (overload) that astronauts are exposed to during takeoff, reaching 7 G (usually people are exposed to gravity at 1 G), is the main cause

anemia produced in their body, a team from the Catholic University of San Pablo in La Paz, Bolivia, consisting of Natalia Agramont, Marcia Carrasco, Belen Flores and Daira Quenta, students of the Faculty of Biochemical and Biotechnological Engineering, under the guidance of their supervisor Georgina Chavez, is studying this phenomenon to prove the correctness this hypothesis.

However, since it is impossible to conduct blood tests at the time of takeoff, it is necessary to conduct an experiment on equipment simulating hypergravity, which is achieved using a large-diameter centrifuge

(LDC). Since constant access to a working LDC is not possible, the work is carried out in the laboratory, under 1 G conditions, to study the resistance of red blood cells exposed to these conditions.

The main part

In order to demonstrate the hypothesis based on the fact that due to the hypergravity that astronauts are exposed to during takeoff, they suffer from anemia upon return, osmotic fragility tests are conducted. This method consists in measuring the resistance of red blood cells to various factors. It reveals how strong their membrane is before producing cell lysis. The study is based on the fact that due to the force to which the human body is exposed when traveling into outer space, red blood cells die, which leads to the loss of a large number of them in the blood. This causes hemolytic anemia, a disease characterized by the absence of red blood cells in the blood.

The algorithm of actions is as follows. First, 12 buffer solutions are prepared with the appropriate concentration of sodium chloride in accordance with a certain variation: 0,0, 0,1, 0,2, 0,25, 0,3, 0,32, 0,36, 0,4, 0,45, 0,55, 0,7, 0,9 % № C1. Secondly, starting with the method itself, the blood sample is centrifuged for 10 minutes at 174 g, after blood centrifugation, plasma is removed and 0.9% solution No. C1 is placed in the same amount of plasma to be removed. Thirdly, the solutions are distributed into centrifuge tubes, placing 4 milliliters in each tube, taking into account the ratio 1/10, 40 microliters of blood are placed in each tube containing the corresponding solution. Fourthly, 12 test tubes are placed in a centrifuge for 10 minutes at 174 g. Finally, the absorption of the filler liquid in the test tubes is read in a spectrophotometer at a wavelength of 540 nm.

After reading the absorption, 0.9% sodium chloride solution is used, the percentage of hemolysis is calculated according to the following equation.

After this procedure, an osmotic fragility curve is obtained, which helps to study the resistance of red blood cells to various factors. The effectiveness of this method is to observe the behavior of blood in front of different solutions with different concentrations. The number of solutions is determined by the parameters observed experimentally, taking into account the realization of hypotonic concentrations, starting with an isotonic solution of 0.9% NaCl, while the solution has the same salt concentration as the saline solution, and, consequently, red blood cells.

Observing the "behavior" of blood, we find a relationship between the concentration and the percentage of hemolysis, while the lowest concentrations contain greater cell death.

In addition to concentrations, a very important factor is the strength of the centrifuge to which the samples are subjected during centrifugation, because the initial hypothesis is based on the fact that the force acting on red blood cells changes their behavior, seeking to cause cell lysis. To this end, tests for osmotic fragility were carried out by varying the forces of centrifugation, observing their effect on red blood cells.

TRANSLATION OF THE TABLE: The graph shows "Osmotic brittleness curves at different centrifugation forces." The abscissa axis indicates the concentration of aC1 (table salt) as a percentage, and the ordinate axis shows the percentage of hemolysis (destruction of red blood cells) as a percentage. Each curve in the graph represents the different weights used for centrifugation.

In this graph, the differences between the various curves are observed due to changes in forces, the first curve that can be analyzed was made at 174 d of centrifugal force, this is our standard, in other words, our control curve, which has a drop between solutions with a concentration of 0.30 and 0.32%, Speaking of a drop as a degradation of concentrations between the point where hemolysis is almost 100%, and the point where there is almost no cell death borders on the percentage of hemolysis of 0%. The second curve that can be observed was exposed to 245 d, which carries a drop between concentrations from 0.25 to 0.30%. The third curve, taken at 398 d, shows a drop between 0.25 and 0.30% concentration solutions, like the previous one. The fourth curve at 876 d shows a drop between concentrations from 0.25 to 0.32%. The fifth and last curve, when exposed to 2033 g, shows a drop in the concentration of solutions from 0.32 to 0.40%.

Conclusion

In conclusion, it can be seen that the strength of the centrifuge, i.e. the force to which erythrocytes are exposed, affects the resistance of their membranes to solutions with different concentrations that affect them on the curves of osmotic fragility.

With the tests carried out, it was noticed that with a higher centrifuge force (at 876 and 2033 g), red blood cells weaken, striving for a high percentage of hemolysis. This proves the hypothesis that the greater the force exerts on red blood cells, the higher their percentage undergoing cell lysis, the greater the rupture of the cell membrane under these conditions.

Application

One of the most important applications of the project is that, thanks to this research, the effects on human health during space flight can be minimized. In the year 2100, space travel will become part of the daily life of mankind. The human body will learn to easily adapt to the conditions of "big space adventures" — flights to the Moon or other planets and their satellites.

Based on the curves of osmotic fragility, determine the form of resistance to the force to which astronauts are exposed, or other factors that may affect cell lysis. If the factors that increase cellular resistance can be analyzed and applied, it will be easier for astronauts to adapt to flights, they will not have a negative impact on their health. In the future, all members of the human community will be able to travel into space, expanding their horizons, exploring unknown places, experiencing exciting adventures - and not worrying about harm to health. This will give a new impetus to the development of all mankind.

It is likely that in the future it will be possible to create space colonies among the planets of our Solar system — Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune. Astronauts from the colonies will explore these planets, discovering their natural resources, new forms of life and new ways of living in spaces that are only available in dreams today. To live on some planets, to travel to others, to expand your boundaries and horizons of knowledge, to live to endlessly wonder at the strange and fabulous in other worlds. This is a real cosmic globalization! All this will be possible thanks to the gradual discovery of methods similar to the one presented in this study. New methods will appear to help the human body adapt to other ecosystems or other worlds larger than ours.

The original is in the application

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