What signs do you look for for a healthy brain?

That's actually a really cool question because we often focus on the unhealthy things in the body, or when it comes to science, or medicine. But understanding what is healthy is actually quite essential as well. 

I think how we define this, is that there are certain abilities we look for, that someone is able to do in their daily life. So with a healthy brain, it's not like you should never forget things - but you shouldn't have excessive forgetfulness. For example, you should be able to carry on your day knowing what you're doing. So, you shouldn't have excessive forgetfulness, and you should be able to do your motor behavior properly - which means that you will walk, you fold things, you do your daily life. You will open doors, you sit down, and then if you have to run - you run. So these are motor abilities that are controlled by the brain. So we expect someone with a healthy brain to be able to do them anytime they wish. 

The cognitive part of the brain is quite essential as well, we can call this mental health, or your mood.

There are certain diseases that we call - mood disorders. So, this defines that like, of course, this doesn't mean that you won't have any emotional changes in the day, but you should be able to have those changes. So that's what's why it's important, so you can feel happy. But then if something bad has happened, you can feel sadness - then come back to your normal state.

So, these changes should be at a level that doesn't affect your day negatively. So that's kind of a healthy state that you're able to feel things, change your mood, but then come back - to whatever the regular state you are. Sometimes if the regular state is leaning towards one mood, then you start thinking - maybe there might be an issue there.

Apart from that, I think cognitive and motor behavior is the main thing that we look at as a first insight. I don't want to give such a detail saying that you shouldn't feel any negative things because then people start thinking - oh, I feel low today - am I not healthy? It's not like that, your day should be content within, and then you should be functioning properly. So, we can conclude that you are actually at a normal stage.

Sleeping is another important part of a healthy brain, because it's the time that the brain shuts down, rests, and actually continues working in the background. This is why we say we should sleep, especially if we are trying to learn things, because the learning is being actually completed, processed while you're sleeping.

So that's another important thing - if your brain is not able to shut down, especially long term, maybe you can start thinking maybe there's a problem there.

When is the brain most active?

You know what we feel as a human, we are a bit entitled - and we think that we're always thinking about something - but actually we are not always thinking about something.

But, our brain has functions to do constantly, because it's managing our basic functions that we are staying alive, our organs are working, our tissues are communicating. So, these are basic functions of the brain, which is not necessarily extra effort, extra activation, but it is there, and it's constantly working. 

But of course, if we are thinking, what are the most active times - these are the times that we are trying to learn something. We are trying to solve a problem which requires our brain to gather all the knowledge you know already, that it's in the memory. Then it's trying to make something new out of it because you're facing a problem. So, in those moments the brain makes a little bit of higher activation than its usual state.

Interestingly, in one part of our sleep, that brain gets the most active prime time. This is why sleeping is so essential if you are in the process of learning something. We should definitely focus on our sleep, as well as sitting and studying, because our brain processes the information that we put in during the day at night, when we are sleeping.

So imagine the brain is someone that has so many different things, then at night, the other so many different things get a bit low. You don't have to consider how the body is walking, or you don't have to deal with digestion because the person has stopped eating.

So, what you need to do at that time is focus on what is the new information taken in the day. So then you make them in the memory, process them, and then complete the learning, for example. This is why it reaches a level that it's quite active at a certain time of our sleep, but not the same reasons that it is being active during the day maybe.

So, this is why learning and problem solving, and the processing at night, is one of the times that the brain is most active.

What are some of the reasons why cancer returns in patients?

This is important in the way that it also tells us about the complexity of the disease. So when someone develops cancer cells, those cells probably will develop a tumour - which means that there is an accumulation of cancer cells in a region. So it develops a kind of ball, imagine it like that - which means that cells divide themselves enough that you can, even in skin cells - skin cancers, for example, you can feel the tumour with your hand on your skin, and it's going to be in that region. 

Then this could be treated by the available treatments, could be surgery, could be combined with chemotherapy. So then we target those cancer cells and try to kill them as much as possible, but even with few cells left with the same mutation - they could reinitiate that process.

So this is why with the ‘all clear’ - of course, they monitor as much as they can. The tests available in medical settings now are trying to cover as much as they can. But, it's not easy to say if there isn't even one single cell left, because cancer cells could be metastatic - which means that they can migrate from one region through blood to another region in the body.

So, if one cancer cell makes it to the blood and then migrates, they can go and colonise another region or they can invade another region, and then they can continue dividing themselves there. Also, cancer cells are another fascinating side of the cancer, but also sad for the patient - of course, as they are quite responsive and dynamic, so when we treat them with something to kill them, they can dynamically reshape themselves - so then they can escape from that drug.

Of course, they are not going to do it the moment we are giving the drug for the first time, but then the ones that remained - if they find the way to escape from that effect of that drug, they might come back, and they might even be a bit stronger, because they probably now have developed resistance to that drug.

So, this is why we monitor those patients throughout their lives just in case, as it might reappear again. But this doesn't mean that this will happen. There are many patients that are given all clear and don’t have it at all again. Also, there are some cases that you might see it's coming back, and if you realise it in good time, you can still continue treating it and then get a positive outcome.

What is a genetic disorder?

How I will answer this is, maybe I should say first, the genetic mean in that question. So what we think usually, anything related to DNA, genes, is genetic - which in a sense, is correct. If you're able to associate a gene to a disease, symptoms that you see, usually what happens, we go to hospital, they examine us, there are certain symptoms they look at.

Then maybe there was research already, and then there is a mutation on a gene associated with those symptoms, then we have our diagnosis. They tell us, okay, you have that mutation on that gene, and this is this disease. 

But, this question could be understood at a level that whether a disease is inherited and that way it's genetically inherited, it's a different angle. I sometimes fear that people use these things with a bit of the same meaning. What we know actually at this level of science we have, most of the diseases have a genetic background - which means that there is a mutated gene which causes the disease somehow. 

But is every genetic disease inherited? Not really. So, we only inherit the things that we have mutated in our germ cells - so the next offspring get those germ cells. Otherwise somatic mutations in our body, so the genetic diseases appeared because of those mutations, they're not going to be inherited, but they're also genetic disorders.

I don't know how clear these answers were, but maybe the question is a bit not clear enough in that sense, but this is what I would say.

Why do some people with severe dementia often remember songs and rhymes?

This is a good question. It tells us the thing about the nature of the disease, actually - so Dementia or Alzheimer's. So, Alzheimer's is one type of dementia. Dementia is a bigger spectrum, about our memory and the function of the brain.

If you think the nerve cells are working together, they are not physically always in touch, but they are working with each other. So this will send a signal, and this will receive the signal - this will initiate a process. Our memory is functioning like that as well. So, we remember things because these neurons are able to communicate.

What happens in dementia cases, that communication is loosened. In time, those neurons die, because they are not able to function. The more we lose the neurons, the more we lose memory and our body function. So, in those cases, people remember old memories more than recent memories, because old memories have more.

Remember that if you have repeated something more, your brain will have that memory more often, so if you have done something today for the first time, and if you develop dementia, you won't have that storage strong enough so you can remember again. One of the symptoms of dementia cases is that you actually lose the ability to store, so this is why you actually don't remember, because you actually didn't store it. 

But you haven't had the disease since you were born, so the disease appeared later, so you already have certain memories stored, and then you have repeated them in songs and rhymes. They actually also have different memories than the short-term memory, you know, the daily things. The long-term memory is stored a bit differently, so this is why we still, you know, when we have those diseases, we still remember the old things, but not the recent things.

But the more disease progresses, that part will be affected as well. Those things will be maybe forgotten, but they are so strong. So this is why, you know, people will remember their parents, but maybe not their own children, because it's relatively recent compared to your parents' memories.

Does ethnicity have an impact on neuron degeneration?

So, let's define neuron degeneration first. The word degeneration is referring to something that has been generated, and they are degenerating. So they kind of exist, and they are like now dying back, or disappearing.

When we were embryos in embryonic development, we started having neurons, brain development and when we were born, we grew our neurons. If they don't have any problem, they will function properly for the rest of our lives. But if they have some problems, neurons are one of the types of the cells that, despite having some problems, can make us long live, at a level that we don't realise those problems yet.

This is why neurodegenerative disease is usually diagnosed at our late ages. So some problems were actually there since birth, but like neuron managed itself to function until a certain age. Then there was an accumulation of that problem, and then couldn't cope with it anymore. 

Is there any difference in terms of ethnicity in those things? I wouldn't say this is at the molecular or genetic level, because ethnicity is a term I would, as a person, I would use more at the social and cultural level. Of course, we have genetic sharing, and within the same ethnic group, we will have more sharing compared to others. But don't forget that that falls into the 1% difference.

The other things, what you expect from an embryo and how it develops, it's going to be the same. If there is a certain type of exposure of things for a certain ethnicity, in a certain region, then you might see that this is impacting the disease development more than others. You know, for example, the regions that lack sunlight affecting vitamin D level, which people conclude saying that the prevalence of multiple sclerosis - which is a type of brain disease, is seen more in those areas. 

Does this define an ethnic link? I'm not sure about that. These things to me are more like environmental factors that ethnic groups are living in. It's not about their genes that's doing something extra, or differently than others to them.

How do new drugs or treatments get approved for prescribed use?

This takes years and a lot of research, a lot of pain for scientists, and maybe sweat of PhD students, master students, a lot of grants from the funders and money. It's a long process. It starts in the labs, research labs usually.

So, if we have a mechanistic insight about the disease mechanism, let's say, we know that this might be the reason for that disease appearing. This is not functioning, and this is why it is happening. Then if you're able to target that dysfunction, maybe you are able to correct somehow, or you are blocking something, and it's making it work. If you know that level of information, you start trying components in the lab. Usually you can start trying them on the cells in a culture petri dish. Then if it responds positively, according to your hypothesis, then you move to the animals. You test the same outcome on the animals. If it is still correlated to what you are thinking, then you apply for clinical trials, which means that you apply to the agencies. 

So for example, you know, an agency linked to the NHS in the UK, or there's FDA in the US. You reach out to them saying that you have a component, you tried cells, you tried animals, and now you wanna gain access to the clinical trial, to human trials in the hospitals. Then there are a lot of checks in between, of course, those agencies, this is why they exist. They sit down and check whether your data is consistent, whether what you're saying is correct. You put placebo trials as well, which means that you don't actually give the components, but in the placebo trial, you shouldn't see the effect that you're assuming to see in the component category. So, all these checks are done, and then the clinical trials start. 

Usually it's a small population of patients that are chosen by the hospital, and with the developer together that they have they have given to the medicine and effect observed. So, if this passes well, then you can get the full approval. But, the first human trial doesn't mean that you're trying to hurt those people, or you have a risk of hurting those people. Of course, before that step, there's a lot of research, and approvals are taken and you have actually shown the effect. The only thing that sometimes we see is that things work on cells, and it works on mice as well - but sometimes it doesn't work on humans because at the end, all the similarities we have, we are different species, different organisms, but the mice in the lab, the closest we can get. So this is why we are relying on that outcome.

But there will be cases that you are not going to see the same in the human condition. Then you either stop continuing the drug, or if you see a positive outcome, then it gets approval by the agencies, and then it goes on to the market and used.

Can brain cells regenerate? 

This is one of the fascinating topics in neuroscience, and there is a lot of research going on, because we wish that they could be regenerating. So the word regenerate is referring to something that has existed, so generated, and then something happened. They may be degenerated, so they lose their features and then function. What we want is for them to come back, and gain that function again. 

This is actually an event in which most of our cells are able to do, they kind of can divide themselves with mitosis, and the dysfunctional one, or the damaged cell, dies out and disappears. The healthy cell divides itself and then gives a new one. So, this is kind of for regeneration, it could be. There is another type of regeneration we can think of is that, let's say part of the cell is damaged, and the cell is only repairing that damaged part. So, that could be a regeneration as well. This is in our body we observe.

In most of the tissues when it comes to the brain, it's a bit hard and tricky, and it's evolved in a way that the neurons are not able to divide themselves anymore, so they don't go through mitosis after they become a mature neuron. So this is sad, of course, because when we have a damage in the brain, it means like we lost neurons, and then they are not going to come back. So, this is why we end up having certain diseases. But it might be kind of understandable why it is not. Because if we think about mitosis, cell division, you know, cells will stop their function, and then replicate the DNA and divide. This means that a cell is suspending whatever the function they are doing for a certain time. I think this is understandable why neurons might not like that, because it means part of our brain will be suspended. So, then they can divide themselves. So if you think that they're able to do mitosis. So that could be actually also negative for the body, because you know these are the problems that we can't tolerate neurons not functioning. So maybe this is why it's evolved in that way. 

But still, you know, it could be quite nice, and it could be a treatment for certain diseases. If we are able to see that regeneration. But in the brain, there are other cells apart from neurons that are, for example, glia, which are the supporting cells for neurons. They are able to divide themselves. There are other types of cells, so they can divide themselves. So, it is the neurons that we don't see cell division. There is a lot of research that we are trying to trigger in case of damages. When we have neuronal loss, maybe for that type of situation, we can trigger regeneration.

So there is a lot of research going on, but what we observe in neurons, let's say so a neuron has a cell body. Imagine like it's my hand, and then the axonal part, it's like my arm. If these axonal parts are damaged, we observe that the neuron is able to regenerate that damaged axonal part. So, they can kind of create a new axon, or they can repair the damaged products, one that we observed a little bit. What we don't observe is the full neuron kind of dividing, and renewing itself. But still partial axonal repair is also regeneration. 

So, the answer is, yes, there are cases that we can see regeneration, but not fully in neurons. There are other types of brain cells that we can see fully, renewal and repair. That will be my answer.

Are there some animals who never get cancer?

Surprisingly, there are.

Elephants and whales are one of the known ones among large animals that don't get cancer - it is fascinating.

There are scientists that actually work on elephant cells and whale cells, in terms of their cancer protection. One thing we know is that they have a gene. Actually, we also have the same gene, but they have around 20 copies of that gene, more than humans. It's called tumour suppressing gene 53, or TP53. 

Elephants have around 20 copies of that gene, whereas humans have one only. That gene is mutated so commonly in human cancers. So, scientists think that this is why they don't have cancer because they have that level of 20 extra protection by that gene, even though they are long living animals, which is quite fascinating. 

Evolutionary, it's not that clear why it multiplies that many times in elephants, not humans. But it could be quite interesting to know why. If we know why, maybe we can actually, you know, find some solutions for humans becoming resistant to cancer one day.

How genetically similar are we?

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