Friday, 23 November 2012

I'm back! Estou de volta!


I am so sorry that I've been away but it was for a good reason.

I got a new job!!!! (I left the bench but not science, don't worry :0)).


For a while I was wondering if I should keep writing the blog but yesterday I was at a career event and a speaker, Ed Yong, an amazing science writer, really motivated me and made me think why should I stop doing something that I really enjoy. Maybe I won't write the blog every day, or even have amazing stories to tell you every week, but I will definitely keep writing it and telling you cool 'sciency' stuff. So you just wait and see. Great things are about to happen :0)


In the meantime, you can have a look at Ed's blog, that's called Not exactly rocket science, there are some great stories there.

Blog to you soon!

---------------

Desculpem ter andando desaparecida mas foi por uma boa causa.
Mudei de trabalho!!!! (mas não se preocupem, deixei a bancada, não deixei a ciência :0)). 

Por um tempo ainda ponderei se devia continuar a escrever o blog mas ontem fui a uma conferência destas de promoção de carreira e um dos oradores, Ed Yong, um escritor de ciência incrível, motivou-me bastante e fez-me pensar por que razão devia eu parar de fazer algo que realmente gosto.

Talvez não escreva o blog todos os dias, ou nem tenha histórias incríveis para vos contar todas as semana, mas com certeza vou continuar a escrever e a contar-vos histórias engraçadas da ciência. Esperem só  p'ra ver. Grandes coisas estão prestes a acontecer:0)!!!

Entretanto, podem dar uma olhadela no blog do ​​Ed, que é chamado
Not exactly rocket science,  tem
histórias porreiras.

Monday, 27 August 2012

Mobility scooters, old ladies and cancer cells. WHAT???


How can a nice old lady riding a mobility scooter be compared to a ruthless cancer cell? You may not know now but you will by the end of my story.



Today I am going to post a piece that I've written a few months ago for a writing competition talking about what I do.

It has a fun side of my writing and since I've enjoyed so much writing it, I've decided to share it with you and see what you think about it. Have I gone to far?

Here it goes:


If you are a scientist, you know exactly what I’m talking about when I say that I have to answer over and over again the question “what is it again that you do?” And even if you’re not, but if you know one, you know how hard it is to explain those weird things that we do in the lab.
 After spending some sleepless nights thinking about my problem (well, not exactly because of this but yes, science can give you insomnia, believe me) I’ve come up with this:
I study a type of proteins called chaperones. Basically what they do is to keep an eye on other proteins’ function, to be sure that everything is in order in a normal cell, a bit like a guardian. The reason why I’m interested in studying them is because cancer cells take advantage of this guardian function to grow and survive, exactly the same way old ladies take advantage of those mobility scooters available on high streets (with all due respect to old ladies, are you starting to see where I’m going with this? Not yet? Don’t worry, you will).
By using the chaperones, cancer cells also become more dependent on them and in our lab we are trying to develop drugs that will inhibit the chaperones specifically being used by the cancer cells, while sparing normal cells. This might still be tricky to appreciate but hopefully with my example you will understand it better.

 Let’s picture this situation: it’s the Boxing Day sales, Mary has finally decided to buy that designer bag she’s been wanting for ages (or the latest gadget if you’re a boy - boys don’t really want designer bags, do they?). Ready, set, go! She takes the tube, then the bus, she walks 3/4 of the street and then she sees them... The army of nice old ladies on their mobility scooters, trolleying down the street, and they pass her, but that’s fine. They would never buy that bag. Would they? And then, suddenly, they get inside that store, yes, that designer store. Mary speeds up the pace (not as fast as a scooter but she does her best), gets inside the store, hair in her face, breathless, her heart pumping at 150b/minute and then... Oh nooo, they bought the bag. Nooooo.
Ok. That’s enough. Let’s get serious and talk about science.
My point is that in this story Mary was like normal cells, growing, dividing, and dying (how does that relate to shopping on Boxing Day? Just think that Mary really wanted that bag, like normal cells want to grow). But cancer cells (our old ladies) do that way faster and just grow and divide and grow and divide, forming tumours. They use chaperones (the mobility scooters) to grow faster. And use them all the time. However by doing that, they also forget how to ‘use their legs’ and become dependent on their ‘scooters’. One of our main goals, like I told you before, is to develop drugs that will block the chaperones used by cancer cells, like pinching the scooters’ wheels or blocking their electric system.
So far, we have found that two co-chaperones (there are several chaperones and co-chaperones working together in a cell, like the different parts of a scooter) are involved in the growth and survival of sarcomas and prostate cancer. We showed that if we block them at the same time, we kill part of the cancer cells, making them more sensitive to treatment with the standard chemotherapy.
We are very excited with these results. Given these two co-chaperones are present in many other cancer types, these findings have a real medical implication and this approach could be used broadly.

In summary: cancer cells are essentially normal cells that have overcome their control systems, surpassing their own ‘suicide’ checkpoints and just growing and dividing. The idea of targeting the mechanisms by which they do this is a very efficient way to block cancer development. With this project we aim to design drugs that will efficiently kill cancer cells, leaving normal cells mostly unaffected, reducing the unwanted side effects of current cancer treatment.
 Before I finish, I would like to thank all old ladies with mobility problems (including my sweet sweet grandmother) for being such an inspiration.  Even though I compare you to ruthless cancer cells, it is only for the benefit of science!
 So please, the next time you ask a scientist ‚”what is it again that you do?”, pay attention, they might have actually come up with a decent story to tell you! 
Lets give this a thought, shall we?
SO?? what do you think about it? Do you know now what I do? 

Monday, 9 July 2012

Higgs or God? Both? None?


 What is this all about “God’s particle”?


Last week CERN* has announced that they have found strong evidences to prove the existence of the Higgs boson. This is a subatomic particle that is important to the understanding of space, time and matter that the physicist Leon Lederman nicknamed "the God particle."

This particle was first proposed in the 1960s by the English physicist Peter Higgs. Since then, efforts to find it have taken decades. Several experiments have been done by independent teams to ensure accuracy and finally there are some evidences that prove Higgs hypothesis.



But why is this so important? After all it is a tinny particle visible for only a fraction of a second! It is believed that the Higgs boson would help explain how we, and the rest of the universe, exist. It would explain why the matter created in the Big Bang has mass. Because without it, the other particles in the universe wouldn't have mass and would all continue to travel at the speed of light. That's it.



 
But better than me, have a look at this video explaining it in a simple way.


More work will be needed to be certain that what scientists have seen is a Higgs, however.

And if you are really keen to learn why we should really care about this, have a look a this link:

higgs-boson-why-you-should-care-about-the-god-particle-and-sadly-why-you-dont/

If you want to explain what the Higgs is to someone else, have a look at this link that will give you some hints and tips regarding the person you would be explaing it:


And if you want to read CERN’s press release, here is the link too.

CERNPressReleases/Higgs

Now that scientists are starting to find evidences of how “all has started”, what do you think about the creationist theory? 

Let’s give this a thought shall we?

*CERN, the European Organization for Nuclear Research, is the world's leading laboratory for particle physics. It has its headquarters in Geneva and houses scientist from all over the world. If you have read Dan Browns’ Angels and Demons book, it was where the anti-matter was stolen from.

Tuesday, 29 May 2012

Is “Social Jetlag” making you fat?


If you love sleeping until noon over the weekends you might want to re-think your habits once you read this blog...


According to a study published this month in the journal Current Biology, researchers from the Universities of Munich and Groningen have shown that people with different sleep schedules on working days and free days (what the researchers called Social Jetlag) had triple the chances of being overweight.

Social jetlag is "the discrepancy between what our body clock wants us to do and what our social clock wants us to do," says Till Roenneberg, a professor at the University of Munich's Institute of Medical Psychology, in Germany. "It almost looks as if people on a Friday evening fly from Paris to New York, and on Monday morning they fly back again.”

Roenneberg and colleagues have surveyed the sleep habits of more than 65.000 European participants, comparing their sleep duration, sleep timings and patterns over working days and free days. They have found out that the Body Mass Index (BMI) of overweight people tended to be higher in those with a bigger discrepancy of sleep between their biological and social clocks (sleep discrepancy did not explain variations in body mass among those with a normal BMI).

These results confirmed previous data that linked higher BMI to sleep deprivation and irregular sleep schedules. Particularly, various studies have found an increased risk of obesity, as well as chronic diseases such as diabetes, among shift workers.

Some of the proposed explanations for the link between shift work and obesity, such as irregular meal times and metabolism disruptions, may help explain these social jetlag findings as well, Roenneberg says. "With social jetlag, we're forced to eat at times when the body doesn't want to eat, or isn't prepared for digesting food properly," he says. "All these things coming together might influence the way you digest food and how you incorporate it into your body fat. The result is that you become overweight or obese."

This study also explained why “teenagers show the largest discrepancy in sleep duration between free days and workdays”. Amongst other obvious reasons (such as playing computer games until late or chatting on their computers/mobiles :0)) this is because developmental changes in their circadian clock are not matched by the school start timings, changes particularly evident and fundamental at this phase.

So what can we do?
Adjusting our sleeping patterns isn’t easy. We just can’t simply rely on our biological clocks to wake up, we have work schedules to keep up to but paying more attention to our body clocks may be good start.

And here goes a link if you want to do a check-up to your sleep

Let's give this a thought, shall we?

Tuesday, 24 April 2012

Even the coolest ones can loose it


Have you ever had one of those moments when your brain just blanks out? Was it a stressful situation? Was it maybe during an exam? Or when you were supposed to remember someone’s birthday and all you could think of was ... nothing ... Just embarrassment... 


Well, don’t worry, science has proven that stress is the reason why you blank out.



This month’s Scientific American has published a review article that explains how stressful situations can trigger signals in our brain, leading to a loss of control over its ‘executive functions’.


According to the authors “when things are going well, the prefrontal cortex acts as control centre that keeps our baser emotions and impulses in check. (...) Acute, uncontrollable stress sets off a series of chemical events that weaken the influence of the prefrontal cortex while strengthening the dominance of the older parts of the brain”.

Essentially, stress is giving control over thought and emotion to the so-called ancient structures of the brain - hypothalamus and other earlier evolved structures - the areas responsible for more basic functions as eating or having fear.

“The growing understanding that acute stress can severely compromise the function of higher “executive” areas in the human brain has drawn the interest of investigators. They are now not just trying to understand what happens in your head when you freeze but also developing behavioural and pharmacological interventions to help you keep your composure”, said the authors.



And now some interesting science bit and bobs. Why does this happen?

1.     The prefrontal cortex is so sensitive to stress because it makes up a full third of the human cortex; it matures more slowly than other brain areas (only reaches full maturity after the teen years have passed); it houses the neural circuits for abstract thoughts and allow us to concentrate and stay focused on task, while storing information and making memories.

2.     Under normal circumstances the prefrontal cortex controls our emotions, desires and habits. However, under stress, the brain is flooded with chemicals such as adrenaline or dopamine, which are released by neurons, and the prefrontal cortex is shut down, passing the control over to deeper, ancient areas of the brain, such as the hypothalamus or the amygdala.

3.     Recent studies have shown that some people may be more vulnerable than others to stress because of their genetic makeup or because of a previous exposure to stress.  Under normal situations, after hormones like adrenaline or dopamine switch off circuits in the prefrontal area, enzymes chew up these neurotransmitters so that the shutdown does not persist. In this way, we can return to our baseline when stress abates. Certain forms of a gene can weaken these enzymes, making people more vulnerable to stress and, in some cases, mental illness.

4.     John Morrison of the Mount Sinai School of Medicine and his colleagues have shown that chronic stress appears to expand the intricate web of connections in our lower emotional centers, whereas the areas in our prefrontal cortex actually shrink. They have shown that prefrontal dendrites can regrow if the stress disappears, but this ability to rebound may vanish if the stress is especially severe.  This chain of molecular events makes us more vulnerable to subsequent stress and most likely contributes to depression, addiction and anxiety disorders, including post-traumatic stress.

5.     Gender appears to be a factor in determining how we react to stress. In women, the hormone estrogen may amplify sensitivity. It has actually been proven that life stress poses a greater risk for depression in women than men and is more likely to reduce abstinence from certain addictive behaviors, such as smoking, for women as compared with men.


Why the brain has built-in mechanisms to weaken its highest cognitive functions, making it “dumber” at key life-decision moments, is still a very intriguing question. Researchers are investing greatly to bring insight in to this matter. In the meantime, the next time you are taking a test or speaking in public and your mind goes blank, say to yourself:  “This is just my brain loosing its grip, hold on, just calm down!”. It maybe not give you the correct answer, but it might bring you a comforting smile. 

Let's give this a thought, shall we?

Saturday, 7 April 2012

A sweet treat for Easter!


Does eating chocolate regularly make you thinner? Not really but don’t loose all your hope because…

Scientists from the University of California believe that there is a link between regular chocolate consumption and a lower body mass index (BMI*).

In a recent study published in the journal Archives of Internal Medicine (March 26th), Dr. Beatrice Golomb and colleagues analysed the diet, exercise and mood levels of about 1000 healthy US individuals and found that those who ate chocolate a few times a week were, on average, slimmer than those who ate it occasionally.

This link remained even when other factors were taken into account, such as the calorie intake (frequent chocolate consumption was actually linked to more overall calories), the frequency of exercise or the mood levels.

According to the authors, it is the how often you eat chocolate that is important rather than how much you eat (they found no link between the quantity of chocolate consumed and the BMI).

Previous studies have shown that chocolate consumption has other metabolic benefits, such as insulin sensitivity, blood pressure and cholesterol levels. To Dr. Golomb and her team, this study “now extends the favourable associations of chocolate to metabolic factors”.

“Chocolate products are often rich in sugar and fat, contributing to assumptions that chocolate boots BMI”, says the team in this report. Nonetheless, one possible explanation for these findings is that the antioxidants present in chocolate (called catechins) contribute to lean muscle mass and reduce weight, as shown previously in studies in rodents. The team suggests that a clinical trial in humans is now needed to see if this is indeed the case.

Study details:

1) The study analysed data from 1018 healthy men and women aged 20 to 85 years old (average 57). 972 patients had their BMI calculated (average 28) and 975 answered the food frequency questionnaire.

2) Data was collected regarding chocolate consumption, calorie intake, saturated fat intake, fruit and vegetables consumption (used as controls), exercise and mood levels.

3) Results have shown that on average the individuals ate chocolate 2 times/week and exercised 3.6 times/week. Chocolate consumption frequency was linked to greater calorie and saturated fat intake and higher mood scales. It was not linked to greater activity but to lower BMI.

In conclusion, before you reach for a chocolate bar next time, think that it is, to a great extent, your diet composition that will influence your BMI, rather than solely the quantity of what you eat.
But, hey, it is Easter, so give yourself a treat (preferably dark chocolate that has antioxidants that fight free radicals ;0) )!!!

Let's give this a thought, shall we?



* BMI is a reliable indicator of body fatness for most people and is used to screen for weight categories that may lead to health problems. It is calculated by dividing one’s weight by the square value of one’s height. Normal values range from 18.5 to 24.9. Bellow that those values a person is considered underweight. Between 25 and 29.9 a person is overweight and above 30 a person is obese. 

Sunday, 1 April 2012

Muddy Kids



To all overprotective parents: it is official, early exposure to germs is beneficial for your kids. So let them go outside and play in the mud!!!!

In a study published last week in the Science journal (on the 22nd of March), researchers have shown in mice that exposure to microbes during childhood protect children from developing asthma and other diseases such as inflammatory bowel disease.




Immunologists think that children’s susceptibility to allergies and other autoimmune disorders may be due to the lack of exposure to germs. They consider an early exposure to bacteria and microbes as an important feature for the healthy development of youngsters’ immune system, which in turn shields them against asthma and other allergies in later life. This theory is called the ‘Hygiene Hypothesis’ and it has now gotten stronger with last week’s findings.




Dr. Richard Blumberg, co-author of the study says, "We have co-evolved with microbes for millions of years. There is a very beneficial role for microbes in health. What our study now shows is the critical importance of those microbes in the earliest periods of life."

Details about the study:

1)     For this study the scientists developed two groups of mice – one germ-free raised under sterile conditions and another one raised under normal laboratory conditions. They found that the animals exposed to germs had a stronger disease fighting immune system. The animals raised in sterile conditions were sicker and had inflammation in their lungs and colon (similar to asthma and bowel problems in humans). The researchers found that this was due to an increase of activity of a special immune cell type called invariant natural killer T cell (iNKT).

2)     Animals exposed to germs in the first weeks of their lives were less vulnerable to infections. Adults didn’t show these beneficial effects. Lack of exposure in early life could not be compensated later on.

3)     The researchers have found that the levels of a protein called CXCL16 were higher in the colon and lung tissues of the sterile mice than in the normal mice and that by blocking that protein they could reduce the number of iNKT and the amount of inflammation in those tissues.


Even thought this study has been made in mice and no humans can ever be that germ-free, it is still extremely important as it opens up a lot of questions about how long this early-exposure window lasts and which microbes are involved. Also, it brings light into a possible mechanism involving the protein CXCL16 and the activity of iNKT, helping immunologist to understand and treat asthma and other autoimmune diseases. 


However, before I finish, I would like to make a quick remark:
When letting your kids going out there and ‘eating of dirt and playing in the mud’, you will always have to be a little bit cautious. If you live in the city, your playgrounds may contain high levels of lead and even if you live in a rural area, you might live near fields that have been treated with soil amendments containing toxic pollutants and antibiotic resistant pathogens. So be cautions, ok? I’m not telling you to just let them loose.


Let’s give this a thought, shall we?

(and by the way, this is NOT an April Fools' prank :0) )