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Last year, there was a comic line about fertilization: "if you complain about life so hard, you shouldn't have taken the first place in that swimming race.".
Recently, from the University of Ulm in Germany (Ulm University in Germany) a study may make you more tired, there is no reason.
Currently, in vitro fertilization is playing an increasingly important role in the treatment of infertility. Children obtained in vitro fertilization are what people call "test tube babies"". This technique has always been a boon for women unable to conceive in natural ways. But as far as our country is concerned, the success rate of IVF in major hospitals is not high, with an average of only about 30%.
Recently, a German study by University of Ulm physicist Andrei Sommer led the discovery of human sperm cells, was wrapped in diamond (a diamond Petri dish) the Petri dish survival time and motion activity are higher than in the traditional polystyrene Petri dish, and using near infrared light can also increase the activity of sperm, alone or both joint use can improve the success rate of in vitro fertilization. This is of great significance for the treatment of infertility.
The traditional in vitro fertilization process takes the sperm and the oocyte separately, puts in the culture fluid, causes the sperm to drill into the oocyte, forms the fertilized egg, then transfers the fertilized egg to the womb. In clinical practice, IVF is usually done on Petri dishes, and almost all of the current culture dishes are made from polystyrene.
Like any type of cell, the sperm also produces reactive oxygen species (ROS) that damage cells during metabolism. Active oxygen due to the presence of unpaired electrons, so the chemical properties are very active, with the cell membrane, protein, lipid interactions, cause a series of crosslinking reaction of cells or even cause body damage. In the body, reactive oxygen interacts with the surrounding material and gets or loses an electron in the process to become a stable structure and lose the ability to damage cells.
Polystyrene material will form a colloidal, nano thickness water film on its surface, but this water film will hinder the interaction between active oxygen and the surrounding material, so it is not conducive to the neutralization and elimination of reactive oxygen species.
Therefore, in sperm and oocytes in culture dish during that time, the equivalent of their sperm has been in the metabolism of free radicals (oocytes surrounded by free radicals is relatively small, so the ratio of sperm free radical damage tolerance), this will cause great damage to cells, sperm will soon they lost their activity, from fast swimming into an almost stationary state, so the fertilization success rate is relatively low.
Generally speaking, the higher the sperm motility in the sample, the higher the rate of success in vitro fertilization, the higher the pregnancy rate.
Because the surface of the diamond is a smooth water film that does not impede the interaction of free radicals with surrounding substances, it protects cells from damaging free radicals. So Sommer and his colleagues wondered if sperm would be cultured on the surface of materials such as diamonds. Would it increase the success rate of IVF?
The researchers then used a thin layer of diamond, less than a micron, wrapped in a quartz culture dish and cultured human sperm, and repeated the same experiment on a polystyrene coated dish. The activity of these sperm cells is divided into four grades, from A (rapid movement, most likely fertilization) to D (completely immobile, not fertilized).
After an hour of standing, they found that the number of A grade sperm in the culture dish of the diamond was 300% of the A grade sperm count in the polystyrene culture dish. The findings were published in the annals of translational medicine Annalsof Translational Medicine. Sommer explained that this may be because the reactive oxygen species are not assembled on the surface of the diamond coated dish and are quickly converted to neutral substances to lose the ability to damage cells.
Previous studies have shown that certain wavelengths of light, such as 670 nm wavelength light (in the red end of the visible spectrum), can improve the mitochondrial ATP (adenosine triphosphate) content, which makes cells more vibrant. The team then tested the effects of light on sperm activity. After thirty minutes of exposure to the band, the researchers found that the number of sperm in the experimental group was two times that of the control group.
These findings suggest that the combination of diamond coated dishes and near infrared irradiation will allow sperm to survive longer and exercise more vigorously, thereby significantly improving the efficiency of in vitro fertilization.
Of course, the price of the diamond wrapped Petri dish is expensive, and the price of the dish used in the study is about $100. But Sommer said the price of the dish might be acceptable, considering that it would cost about $10000 or more for in vitro fertilization.
"The study is not only interesting but also important for the development of reproductive biology," says Ashok Agarwal, a biologist at the reproductive medicine center at the Cleveland clinic in Ohio.
But some researchers worry that diamonds can cause damage to sperm and fertilized eggs. Sommer also responds that the study does involve the involvement of nanodiamond particles in sperm cells, but this does not happen if sperm cells are on the surface of inert diamond particles. Still, the study is a long way from clinical practice.
Perhaps in the future, a healthy babies are ordered from a diamond coated Petri dish to start. Guangzhou Mai Zhi medical equipment http://www.ltxtcps.cn。