Against HIV, depression and cancer: 5 promising medical advances
Priorities in medical science are difficult to set: budgets always remain less desirable, and the danger of certain diseases for humanity may be underestimated. People live longer, which means they are more likely to live to cancer or dementia; The importance of mental health is also discussed more than ever before. We talk about five medical developments that can potentially benefit almost everyone.
Olga Lukinskaya
Contraceptive with HIV protection
Recently, we talked about pre-exposure and post-exposure prophylaxis of HIV: in combination with condoms, it reduces the risk of contracting HIV in people with whom it is elevated. Prevention involves the daily administration of powerful antiviral drugs in pills, which, of course, for various reasons, is not suitable for everyone. In an attempt to make prevention more reliable, scientists have developed a tool only for women - a vaginal ring that releases an antiviral drug.
Clinical studies are underway, that is, how the device works with real women. Researchers are trying to apply different doses of active substances and different schemes: for example, a ring can be used for 90 days without a break, or it will have to be changed once a month; the device may contain only a drug for the prevention of HIV or its combination with hormones for a contraceptive effect.
For a ring for a month, containing only dalpivirin (antiviral drug), has already been proven effective in terms of HIV prevention. The dual function ring - contraceptive and prophylactic - has so far been studied only in a short study: it was well tolerated, and the levels of drugs in the blood corresponded to the ones needed for the corresponding effect. Now began a longer study of the device - women will use it for three months.
Treatment of herpes for the prevention of dementia
Almost everyone has herpes simplex virus, and infection is manifested by the appearance of itchy lip blisters. Eliminate this virus from the body does not work, he "lives" in the cells of the immune system and neurons and may not manifest itself for a long time. The rash that appears when the virus is activated is unpleasant, but not to the extent that the priority in scientific research has been given to combat it. True, the situation has changed - in the fall of 2018, the world over talked about the connection between Alzheimer's disease and dementia with the herpes simplex virus.
In the publication of a scientist from the University of Oxford, Ruth Yitzchaki, it is said that, in carriers of a particular mutation, the cause of Alzheimer's disease is likely to be this particular virus, which is periodically activated in brain tissues, gradually damaging them. Virus DNA is found in amyloid (protein) plaques typical of Alzheimer's disease. Itzhaki notes that in some studies, the herpes virus was detected only in a small proportion of people with dementia, but it convincingly explains why this may be due to problems with laboratory methods or other errors.
So far, all studies have noted only the fact that the herpes virus and Alzheimer's disease are related - but it has not been confirmed that the relationship is causal. However, in Taiwan, a fairly large population has already demonstrated that antiviral therapy can reduce the risk of dementia. These data can change the approach to the disease around the world: screening programs can be expected to help identify people with an increased risk of Alzheimer's disease, and pharmaceutical companies will start developing effective and safe herpes vaccines.
Face transplantation and tissue growing
At this point in the world, about forty facial transplants have been performed - not much in comparison with, for example, kidney transplantation, but enough to already talk about the possibilities and difficulties of such treatment not only in the framework of experiments. The operation can last a day or longer and requires the coordinated work of several dozen doctors and nurses. If a person has suffered as a result of an accident or a gunshot wound, not only the skin and muscles are lost - the bones of the jaws and eye sockets must be repaired. At the same time, a transplant operation is just the beginning, because after it there remains the risk of transplant rejection and special therapy is needed to prevent this complication.
Frenchman Jerome Amon became a man whose tissue rejection occurred eight years after face transplantation - and in 2018 he was successfully re-operated. This is the first time in the world that a face transplant was performed twice, and Jerome is now called a "three-person person". Of course, forty operations for the whole world are not enough, but this also means that doctors have experience and practical knowledge. In Russia, a face transplant was performed once, in 2015.
A separate problem - both technical and ethical - is the search for a donor. Fabrics must be fresh and compatible with the body of the recipient, and the procedure must be clean from the point of view of the law. Moreover, if we talk about the consent of the relatives of the deceased, it may be easier to agree to donate a kidney or heart than to give the person of your loved one to another person. Ethical difficulties and problems with the risk of rejection will be resolved when it becomes possible to grow tissue from intact cells - and scientists are actively working on it. The University of Ohio has developed a method that, in animal experiments, made it possible to quickly recover any destroyed tissue, from vessels to nerves. However, so far it is far from being able to apply technology to people.
Genome Editing and Cancer
CRISPR technology is usually talked about in the context of editing the embryo genome - with all the ethical complications involved. Last year, in China, the birth of the first genetically modified children was reported, thanks to the editing of the genome that became immune to HIV. The news provoked a scandal: more than a hundred reputable scientists condemned the experiment, and the research institute, where it was allegedly carried out, said that the author had not been working there for a long time. Of course, this is a difficult question - on the one hand, if there are opportunities to prevent congenital diseases like cystic fibrosis, it would be great to use them. On the other hand, the arguments of opponents of genome editing are quite understandable, comparing it with the development of weapons and pointing to the contradiction of the Hippocratic Oath.
The CRISPR / Cas9 technology is also discussed in another context: theoretically, it can be useful in any conditions associated with DNA mutations, which means it can become a new cancer treatment method. In immuno-oncology, CRISPR / Cas9 technology is attempted to be applied in order to change the genetic properties of T-lymphocytes and force them to attack tumors. The first injection of cells with edited genes was introduced in 2016 to a patient with lung cancer in China - details have not yet been disclosed, but the authors of the study report that "everything is going well." Now the research of the new method is going on in different countries, and people with different types of malignant tumors are participating in them.
Quick-acting depression medication
Ketamine, a drug that has been used for intravenous anesthesia for many years, has been shown to have an antidepressant effect. Scientists have clarified its mechanism of action, and now the drug is undergoing a new wave of interest - now as a means to treat depression. It turned out that intravenous ketamine infusion can eliminate the symptoms of depression within a day, while traditional antidepressants take several weeks to work (and for some people they are ineffective).
So far, scientists are only talking about theoretical possibilities and that on the basis of ketamine, safe and effective antidepressants can be developed. True, American private clinics quickly turned ketamine infusions into a fashionable service for patients and a profitable business for themselves - they offer to “reboot their lives” for $ 495 a month, without really examining patients and even sometimes without a psychiatrist. It is clear that such an approach can be dangerous; it is worth remembering that the drug itself is capable of causing dependence, so that without the supervision of a specialist it can not be used.
Pharmaceutical companies have begun to develop antidepressants similar to ketamine, but safer and more convenient to use - including tablets. For the intravenous drug Rapastinel, the FDA issued a permit for accelerated registration in 2014; the company that developed it plans to bring the drug to the market in a couple of years and take on a version that does not require injections. Documents have already been submitted for the registration of ascetamine, another high-speed antidepressant in the form of a nasal spray.
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