With the start of the anti epidemic war, in the process of large-scale nucleic acid screening, new rumors about covid-19 nucleic acid testing also took the opportunity to rub the heat. For example, do not eat oranges or drink coke before the covid-19 test, which will change the pH in the mouth and lead to a positive test result. Another example is that the cotton swabs used to make nucleic acid poke throat contain fluorescent agents, which can cause cancer and so on. What is the truth? The latest scientific gossip list refutes the rumors about the new crown.
Rumor: the sampling swab tested by Xinguan is poisonous
truth
There are rumors that the cotton swabs used for nucleic acid detection and antigen detection are stained with toxic carcinogens such as fluorescent agents, which will lead to pharyngitis and even cancer. In fact, the swab used for detection and sampling does not contain any reagent, nor does it need to contain reagent. At the same time, sampling swabs belong to medical devices, and the basic requirement is non-toxic and harmless. The claim that the sampling swab is poisonous is completely nonsense.
Cotton swabs in daily life are made of absorbent cotton. The sampling swab looks similar to ordinary cotton swabs, but the top is actually a flocking swab. The flocking swab is made of nylon fiber flocking technology, and the front end is coated with nylon short fibers fixed vertically, so that there are no absorption holes in the collection area of the whole collection swab.
In this way, the collected samples will not be dispersed and retained in the fiber, which is conducive to faster and more efficient sample elution. Relevant data show that flocking swabs can elute more than 85% of the sample collection volume. In contrast, cotton swabs made of absorbent cotton cannot completely collect and elute samples because of their strong absorption capacity.
Rumor: eating oranges and drinking Coke will lead to positive antigen test
truth
The covid-19 antigen detection kit has been put on the market, making rapid detection more convenient. However, will the self-test results of specific groups be affected by factors such as diet?
Antigen detection should be carried out in strict accordance with the instructions. If the operation does not meet the standards, the results obtained are meaningless, but it cannot be considered that the antigen detection results are inaccurate. The principle of the detection kit is simply to capture virus antigens through specific antibodies, but the combination of antigen and antibody needs to occur at an appropriate pH (PH). Under normal circumstances, the sample treatment solution soaked with swabs contains a buffer system, which can ensure the binding of antigen and antibody at the appropriate pH. However, if cola, orange juice and other liquids are directly dropped on the antigen detection kit, the inappropriate pH value will cause non-specific false positive results.
So, can you do antigen detection after eating acidic food? The answer is yes. The swab needs to be soaked in the sample treatment solution after sampling before testing. The sample treatment solution contains Tris glycine, high concentration sodium chloride and other substances, which can effectively stabilize the structure of the gold labeled antibody and avoid interfering with the reaction. As long as the collected swab is mixed with the sample treatment solution according to the standard operation process, there is no need to worry about false positives caused by acids.
Rumor: sleeping in the east-west direction will lead to insomnia
truth
Some people think that when sleeping, the body should conform to the direction of the earth's magnetic field, that is, lying north-south. Sleeping with things will lead to insomnia. In fact, the earth's magnetic field has little effect on the human body.
In this regard, experts from the sleep disorders coordination group of the Chinese Medical Association said that human beings are in various magnetic fields all the time, and the human body also has magnetic fields, but the human body's magnetic field is one tenth of the earth's magnetic field strength, and the two have established a certain balance. Therefore, the influence of the earth's magnetic field on the human body is negligible. At present, there is no research that can confirm that the direction of lying down will affect the quality of sleep.
Insomnia is mainly caused by sleep rhythm disorders, such as often changing work and rest times, sleeping late and getting up late, and doing things unrelated to sleep in bed (reading books, playing mobile phones), which may affect human rhythm and aggravate insomnia.
In addition, insomnia is also affected by age, genetic factors, health environment and so on. Mental diseases and taking drugs will also cause sleep disorders to varying degrees. It is precisely because there are many reasons for insomnia, so the treatment of insomnia cannot be given to thousands of people. Targeted treatment programs should be given, including improving the sleep environment, establishing good living habits, improving emotional state, appropriate drugs and physical therapy.
Rumor: frequent hand shaking is Parkinson's disease
truth
The term of hand shaking is called tremor, which is a typical symptom of Parkinson's disease in the public's eyes, but the presence of hand shaking symptoms does not mean that there must be Parkinson's disease. Psychological stress, muscle fatigue or taking some drugs can also lead to tremor. On the other hand, not all patients with Parkinson's disease will shake their hands - some patients only have limb stiffness without tremor, which is called non tremor Parkinson's disease.
In fact, bradykinesia is the core symptom of Parkinson's disease. The patient may feel that the fine actions such as brushing teeth and beating eggs are inflexible, the arm cannot swing freely when walking, the writing becomes smaller, and the expression becomes dull. Patients may also have trunk roll, limb involuntary movement or obvious postural abnormalities in some periods, which is called dyskinesia or dystonia in medicine.
With the progress of the course of disease, patients with advanced Parkinson's disease will have symptoms such as unstable walking and easy to fall, and eventually cannot walk independently and need to rely on a wheelchair or lie in bed.
In addition, Parkinson's disease also has many non motor symptoms, including olfactory failure, depression, sleep problems, decreased intelligence, frequent urination, intractable constipation, etc. it usually requires the participation of multiple disciplines to provide a better comprehensive treatment plan, not just to see whether the hand trembles or not.
Rumor: negative pressure ward will cause patients to have difficulty breathing
truth
The negative pressure ward mainly treats patients with infectious diseases transmitted through aerosol and droplet respiratory tract. Because the air pressure in this kind of ward is lower than that outside the ward, only fresh air outside is allowed to flow into the ward, and the air polluted by pathogens in the ward will not leak out, but will be discharged to a fixed place in time through a special channel.
Although the air pressure of the negative pressure ward is smaller than that of the outside world, it is generally only 15 PA less, while the atmospheric pressure on the ground is generally about 100 kPa, and the change of 15 Pa will not affect the patient's breathing at all. Moreover, the professional negative pressure ward is equipped with fresh air equipment. The fresh air entering the ward needs to be purified, and the discharged air also needs to be fully treated to ensure safety before it can be discharged into the external environment.
Rumor: taking smart drugs can improve candidates' concentration
truth
Seeing that the college entrance examination season is coming, some parents hope to buy smart drugs to improve their children's concentration in order to make their children get good grades. The so-called medicine that can improve concentration was once popular among candidates and parents, online writers, postgraduate entrance examination and public examination in the name of smart medicine. In fact, smart drugs are actually central nervous system stimulants such as modafinil, Ritalin and Minda, which belong to a class of controlled psychotropic drugs.
Such drugs are used clinically to treat children's attention deficit and hyperactivity disorder, severe narcolepsy, etc. healthy people will feel energetic at the beginning of taking them, but they will soon show side effects such as nausea, insomnia, headache, and may also form drug dependence.
Rumor: food made of glutinous rice is difficult to digest
truth
People think glutinous rice is difficult to digest, probably because Tangyuan, yuanxiao, babaofan and other foods also contain a lot of sugar and fat, giving people a greasy feeling. In fact, sticky glutinous rice is easier to digest than other pasta.
Staple foods that people often eat, such as rice and white flour, mainly contain amylose, while more than 99% of glutinous rice is amylopectin. Its molecular structure is more forked, so it is easier to gelatinize. When the human digestive system decomposes starch, it hydrolyzes it from the end of the molecule, so amylopectin with many branches is actually more efficient to be hydrolyzed and digested.
However, because of faster digestion, compared with the rice flour we usually eat, the glycemic index (GI) of glutinous rice is also faster (GI of rice is 82, while GI of glutinous rice is 87), so we should not eat too much at one time.
August 02, 2022
