1959- 12, Weidenbach, a pediatrician in West Germany, first reported a rare case of baby girl malformation. 196 1 year 10 months. At the conference of gynecology in former West Germany, three doctors reported that many babies had similar deformities. These deformed babies have no arms and legs, but their hands and feet are directly connected to the body, much like the limbs of seals, so they are called seal limb deformed children and seal fetuses. In addition to the above deformities, it will also cause other deformities. Medical research shows that the cause of fetal seal is that women take thalidomide in the early pregnancy. Thalidomide was first synthesized by a pharmaceutical company in West Germany in 1953. Entering the clinic, 1956 was put on the market for trial sale, and 1957 was a German patent. The medicine has a good antiemetic effect on pregnant women and has no obvious toxic and side effects. It has been approved for sale in 5 1 countries. From the listing of thalidomide 1956 to the withdrawal of 1962, more than 30 countries and regions around the world (including Taiwan Province Province, China) reported more than 10000 cases of seal fetus 10000. The incidence of malformed babies in various countries is positively correlated with the sales of thalidomide in the same period, such as at least 6000 cases in West Germany and 500 cases in Britain. Only the United States, due to the cautious attitude of the government, did not introduce this drug. Therefore, there are basically no such cases except for a few cases of deformity caused by being brought into the body of users from abroad. Thalidomide-induced fetal malformation has become the biggest catastrophic event of drug-induced congenital malformation in the 20th century, and there is still legal controversy. Thalidomide is the first drug with obvious teratogenic effect on human beings. Since then, large-scale drug teratogenic research has been carried out all over the world, and it has been found that many drugs have teratogenic effects to varying degrees.
Thalidomide has very low general toxicity to humans and animals. For example, taking 14 grams will not kill people. But it can selectively act on embryos, and its toxicity to embryos is obviously greater than that of mothers, and its teratogenic effect on fetuses can be as high as 50%-80%. If it is taken in the third to eighth week of pregnancy, the teratogenic rate of its offspring can be as high as 100%, and the teratogenic dose to human embryos is 1 mg/kg.
The teratogenic experiments on dozens of different kinds of animals show that thalidomide has different teratogenic effects on about 15 kinds of animals, and the teratogenic effects of different kinds are obviously different. Most kinds of mice and rats are not sensitive. Several kinds of rabbits and most primates are sensitive and can observe limb deformities or short limb deformities similar to human beings. Giving a dose of thalidomide to female monkeys in the sensitive period can cause 65,438+0,000% of their fetuses to have seal limb deformities.
Related research shows that the toxicity of thalidomide to embryos has obvious timeliness, that is, sensitive period. Taking thalidomide during different pregnancy can cause different deformities. If you take medicine 34-38 days after menopause (20-24 days of pregnancy), it can cause tooth loss and cranial nerve malformation; If you take the medicine 36-45 days after menopause, it can cause heart and blood vessel malformation; Shortness of arms and feet is caused by taking medicine 38-47 days after menopause; However, taking medicine after 50 days of menopause generally does not cause deformity. The results show that the fetal malformation caused by thalidomide is not mainly the toxicity of drugs, but the strong teratogenic effect of drugs.
Recently, it has been confirmed that the teratogenic effect of thalidomide is limited to one of the two enantiomeric chiral molecules in its composition, and the other molecule is safe. The chemical drugs invented by human beings not only bring great benefits to human beings, but also cause unexpected harm to themselves. Blind dependence on chemical drugs and drug abuse have caused many undue tragedies. One of the most typical cases is the famous reaction stop event.
From 65438 to 0959, deformed babies with abnormal hands and feet were born all over West Germany. Dr. Lentz investigated this kind of freak, and published "The reason of deformity is hypnotic thalidomide" in 196 1, which greatly shocked people. Thalidomide is a drug taken by pregnant women to prevent vomiting in early pregnancy, which is the cause of deformed babies.
Between the first two months of pregnancy, the mother who took thalidomide gave birth to such a deformed child. This kind of baby has shorter hands and feet than normal people, or even no hands and feet at all. By the end of 1963, more than 12000 poor babies in the shape of seals were born in various parts of the world, such as West Germany, the United States, the Netherlands and Japan.
After investigation, it is confirmed that within 34 ~ 54 days after the mother stops menstruating, various symptoms will appear sooner or later after taking this medicine.
Under normal circumstances, the genetic life code, the length of hands and feet, having five fingers and so on. Should be formed regularly according to the instructions. However, thalidomide drugs will hinder this instruction in a certain part, leading to deformity of children.