PRIORITIES IN MEDICAL SCIENCE IS DIFFICULT TO SET: budgets always remain less than desirable, and the danger of certain diseases to humanity can be underestimated. People are living longer and longer, which means they are more likely to live to cancer or dementia; the importance of mental health is also being discussed like never before. Here are five medical developments that can potentially benefit almost everyone.
HIV- protective contraceptive
We recently talked about pre-exposure and post-exposure prophylaxis of HIV: when combined with condoms, it reduces the risk of HIV infection in people who have it. Prevention means taking powerful antiviral drugs in pills every day, which, of course, is not suitable for everyone for various reasons. In an effort to make prophylaxis more reliable, scientists have developed a female-only drug – a vaginal ring that releases an antiviral drug.
Clinical studies are underway now , that is, they are studying how the device works in real women. Researchers are trying different doses of active substances and different regimens: for example, the ring can be used for 90 days without interruption, or it will need 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.
A monthly ring containing only dalpivirine (an antiviral drug) has already been shown to be effective in preventing HIV. The ring with a dual function – contraceptive and prophylactic – has so far been studied only in a short-term study : it was well tolerated, and blood levels of drugs were appropriate for the corresponding effect. A longer study of the device has now begun – women will use it for three months.
Treating herpes to prevent dementia
Almost everyone has herpes simplex virus, and the infection is manifested by the appearance of itchy blisters on the lips. It is impossible to eliminate this virus from the body, it “lives” in the cells of the immune system and neurons and may not manifest itself for a long time. The rashes that appear when the virus is activated are unpleasant, but not to such an extent that the fight against it is given priority in scientific research. True, the situation has changed – in the fall of 2018, people all over the world started talking about the connection between Alzheimer’s disease and dementia with the herpes simplex virus.
In a publication by a scientist from the University of Oxford, Ruth Yitzhaki , it is said that in carriers of a certain mutation, the cause of Alzheimer’s disease is most likely precisely this virus, which is periodically activated in the brain tissues, gradually damaging them. The DNA of the virus is found in the amyloid (protein) plaques typical of Alzheimer’s. Itzhaki notes that in some studies, the herpes virus was detected in only a small proportion of people with dementia, but convincingly explains why this may be due to problems with laboratory methods or other inaccuracies.
So far, all studies have noted only the fact that the herpes virus and Alzheimer’s are related – but it has not been confirmed that the relationship is precisely causal. However, in Taiwan, it has already been demonstrated in a fairly large population that antiviral therapy can reduce the risk of dementia. This data could change the way the world is approaching the disease: screening programs can be expected to help identify people at increased risk of Alzheimer’s disease, and pharmaceutical companies will take on the development of effective and safe vaccines against herpes.
Facial transplant and tissue culture
By this time , about forty face transplant operations have been carried out in the world – not enough in comparison with, for example, a kidney transplant, but enough to already talk about the possibilities and difficulties of such treatment, not only within 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 is injured as a result of an accident or a gunshot wound, then not only the skin and muscles are lost – the bones of the jaws and orbits must be restored. At the same time, the transplant operation is only the beginning, because after it there is a risk of transplant rejection and special therapy is needed to prevent this complication.
Frenchman Jérôme Amon became the man who suffered tissue rejection eight years after his face transplant – and in 2018 he successfully underwent a second operation. This is the first time in the world that a face transplant has been performed twice, and Jerome is now called “the man with three faces.” Of course, forty operations for the whole world is not enough, but this also means that doctors gain experience and practical knowledge. In Russia, face transplantation was performed once , in 2015.
A separate problem – both technical and ethical – is the search for a donor. The tissues must be fresh and compatible with the recipient’s body, and the procedure must be legally clean. In addition, 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 face 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 tissues from intact cells – and scientists are actively working on this. The Ohio University developed a method that, in animal experiments, made it possible to quickly restore any destroyed tissue – from blood vessels to nerves. True, it is still very far from the possibility of using technology in humans .
Genome editing and cancer
CRISPR technology is usually spoken of in the context of embryonic genome editing – with all the accompanying ethical complications. Last year, China reported the birth of the first genetically modified babies, thanks to genome editing, who became immune to HIV. The news provoked a scandal: more than a hundred respected scientists condemned the experiment, and the research institute where it was allegedly carried out stated that the author had not worked 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 to the development of weapons and pointing out the contradiction of the Hippocratic oath.
CRISPR / Cas9 technology is being 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, the CRISPR / Cas9 technology is being used to change the genetic properties of T-lymphocytes and force them to attack tumors. The first injection of cells with edited genes was injected in 2016 in a lung cancer patient in China – details have not yet been disclosed, but the study’s authors 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 involved in them.