The top three news stories of the week, as chosen by our resident students. This week’s top stories include proof we actually do grow new brain cells into old age, a breakthrough in the contagious facial tumors devastating the Tasmanian Devil, and a warning about taking that post-doc position.
By Brooke Lumicisi
Humans make new brain cells into old age
A recent study has reported that we may actually be making new brain cells all through our life, contrary to popular belief. The team from Columbia University looked at the brains of 28 men and women after death and found that although their ages ranged from 14 to 79 years, there was no difference in the number of immature neurons (brain cells) in the regions analysed. This is in contrast to rodents and primates, where the number of developing neurons goes down with age.
There are a particular type of cell in the brain called progenitor stem cells or ‘mother cells’. These cells don’t have any function in the processes of the brain, but when required these cells can make new cells that will go on to develop into neurons. It is thought that we are born with a finite number of these cells. Indeed, the team found that the number of these cells was decreased in the aging brain, however the cells that they produce was not. This may mean that we are still able to make enough new cells to make neurons even with fewer mother cells.
Interestingly, there was a drop in the number of cells producing key substances linked to neuroplasticity. Neuroplasticity is the ability for the brain to adapt and change in response to environmental cues by making new connections. This suggests that we may continue to make new brain cells, but as we get older these are less active than previously.
These findings were carried out in healthy brains, and it will now be important for the team to look at brains from those will neurological disorders such as Alzheimer’s disease.
Read the full article here
Speak of the devil
Published this week in the journal Cancer Cell, a group from the University of California have genetically linked two transmissible tumours found in the Tasmanian Devil, and found them susceptible to certain human anti-cancer drugs. These scrappy little marsupials, native to the island state of Australia from which they get their name are one of a handful of animals that are susceptible to this rare form of cancer that can be transferred from one animal to another like a contagious infection. In the ‘Tassie devils’ the cancer is transferred by face biting during the fighting process. The contagious tumours have become a real problem for the species, and a cure or vaccine is needed as it now threatens the species.
The team lead by Maximillian Stammnitz compared the genetic code and the functional qualities of the two cancer types and found that they had many similarities, despite these being distinctly different forms of cancer. In order to try to discover more about potential factors for the cancer causing properties of these cells, the team tested a number of anti-cancer drugs that are currently available to humans. They found that the tumours were particularly susceptible to a group of drugs that target molecules known as receptor tyrosine kinases. These group of molecules are involved in the processes by which cells respond to what is going on around them, send signals to the rest of the cell, and result in a specific function such a movement, growth, or death. Receptor tyrosine kinases are targets for many cancer drugs. In regards to the tumor transmission in the Tasmanian devils, this could be related to the way the animals fight. When they are attacked they often receive large, very deep wounds on their faces due to being bitten. Receptor tyrosine kinases are key players in wound healing processes. A defect in these molecules, could be what is driving the development of these tumors.
The drugs are yet to be tested in diseased animals. However, it gives a glimmer of hope to a species in dire straits.
Read the full article here
Are post-doc positions driving down our salaries?
I don’t want to finish on a downer, but if like me you are coming to the end of your PhD and weighing your options a recent study may give you some food for thought. A study published in Nature Biotechnology, suggests that if you are not planning on staying in academia it may be more beneficial to skip that oft recommended first post-doc position.
The study examined a cohort of more than 10,000 US-trained PhD recipients who qualified between 1980-2010 and inflation-adjusted salary, a decade post-graduation was recorded. It showed that the annual salaries of PhD holders that didn’t do a post-doc were significantly higher than those who did, by an average of $12 000 pa.
Doing a (or usually several) post-doc is essential if you want to obtain a faculty position in a research institution and is integral to the functioning of the academic research industry as a whole, providing a relatively cheap workforce. However, the number of PhD students has skyrocketed in recent years with the number of faculty positions nowhere near tracking this increase. In fact, the Royal Society has stated that 95% of PhD graduates will leave academia. There are benefits to doing a post-doc obviously. It is the natural progression into employment for most PhD students. It allows young researchers to increase their skill set in a familiar environment (lab based) while also giving many the opportunity to experience and learn from living in a new city/country/continent. Maybe, we need to be better at identifying the skills we are learning in these positions and using these as leverage when vying for posts outside of academia. Something that career scientists are quite bad a doing.
So, if you are sure academia is not the path for you and your annual salary is important to you, maybe it’s time to reconsider that post-doc………
Read the study here
Lastly, find out more about our cover star here. The little rock star turtle that has unfortunately just been added to the endangered species list