Is the technology giant doing medical care ? After reading this pothole technology you will know! Everyone knows that the technology giant Google officially changed its name to Alphabet. In a few days, we saw another news: Alphabet's Google Life Sciences division signed a partnership with Dexcom, the world's leading manufacturer of blood glucose meters, to work together to create a "coin-sized" blood glucose meter. Among them, Dexcom is responsible for sensor development, and Google Life Sciences is responsible for miniaturization and data processing. Wait, are we really not mistaken? Want to develop a blood glucose meter with Dexcom? So where is the Google contact lens that can measure blood sugar in the legend? ! To know that at the beginning of last year, Google contact lenses have earned enough attention. Why did Google’s life sciences department start a new blood glucose meter development project after a year and a half? Further research found that, as early as 2011, Microsoft has launched a contact lens project to detect blood sugar, and currently the co-founder of Google contact lens project Babak Parviz is a member of the Microsoft contact lens research and development team. Now when I go to search for "Microsoft Contact Lenses", most of the reports that "Google Smart Contact Lenses are not new Microsoft has already started" can not find a special report on Microsoft contact lenses. Then, whether this technology is "the star of tomorrow" or "the king of the potholes", we look down. Is there glucose in the tears? Really! The basic principle of measuring blood glucose with contact lenses is to determine the correlation between the glucose content in the tears and the glucose content in the human blood, and then indirectly calculate the blood glucose level by measuring the glucose content in the tears. So let's see first, where is the glucose in the tears coming from? The main tears (the cornea and the conjunctiva are also secreted in small amounts) are secreted by the lacrimal gland located in the upper part of the eye. Normally, the tears are discharged through the tear duct at a constant speed, and are concentrated in the corner of the eye near the bridge of the nose through the entire eyeball. Through the upper and lower tear ducts, enter the lacrimal sac and finally drain into the nasal cavity. Now think about "a nose and a tear", will it make sense. However, where does the glucose in the tears come from? There is no final conclusion yet. There is currently little evidence that glucose in the tears may come from the cornea and conjunctiva. For example, there is a GLUT-1 glucose transporter in the cornea, but not in the lacrimal gland and conjunctiva; however, there is a sodium/glucose cotransporter SGLT-1 in the conjunctiva. This transporter determines the glucose transfer and sodium glucose concentration. Transfer out to maintain the stability of the glucose concentration in the tears. Although the source of glucose in tears is not known at present, this does not affect the enthusiasm of scientists to study the relationship between tear glucose and blood glucose. The reason is also very simple: even if I don't know how the tear glucose comes from, as long as it is related to blood glucose, we can use it. It seems to be the truth. Next, let's take a look at whether this is the case. Why is this actually a pothole technology? Since there is indeed glucose in the tears, and some researchers have assumed that it is associated with glucose in the blood, then we first look at the glucose content in the tears. First, the amount of basic tear secretion is very small. Mishima et al. discovered in 1966 that under normal conditions, the basal secretion of tears (normal secretion without stimulation) is between 0.5-2.2 μL/min, and the average secretion is 1.2 μL/min. The amount of secretion per day is also between 0.72-3.2 mL. In general, to complete the measurement of tear glucose, at least 10 μL of tears are required to fill the measurement chamber in the contact lens. It can take at least 5-20 minutes for the lacrimal gland to secrete 10 μL of tear fluid. There is a serious lag in time. Second, different test methods, sampling methods have an effect on the concentration of glucose in the tears. The graph below shows the tear concentration of healthy adult tears measured by different research teams since 1937. The measurement methods in the above figure are the same, some different. However, no matter the different methods or the same method, almost no similar concentration range can be obtained. In other words, when you use different measurement methods, sampling methods, and even choose different experimental groups, you will find that the concentration of glucose in the tears falls in a completely different range. So which measurement method should we believe? Third, because the concentration of glucose in the tears is very low, the accuracy of the miniature sensor is extremely high. Mass spectrometry (ESI-MS, mass spectrometer is mostly a few hundred kilograms or more) is considered to be a detection method with high specificity and high sensitivity, so the tears measured by ESI-MS method in the above figure Sugar concentration, recently received the true tear sugar concentration. From the above measurement concentration, the tear sugar concentration should be only a few tenths of the blood glucose concentration, or even a few thousandth. In the previous article on blood glucose meters (here added the link to the article), we have concluded that the effective measurement range for the FDA-approved minimally invasive blood glucose meter Dexcom G4 is 2.22-22.2 mmol/L. Therefore, microsensors have a long way to go to measure such low glucose concentrations in tears. Although there are a large number of studies showing that the tear concentration of diabetic patients is higher than that of healthy people, the difference is completely negligible compared with the difference between them and blood glucose concentration. Penis Rings,Cock Ring Vibrator,Cock Vibrator Ring,Cock Ring Set 3 Penis Rings Shenzhen Dongchen Hey E-commerce Co.,Ltd. , https://www.xxsexytoy.com