Tuesday 23 July 2013

Magnetic stem cells

One of the most difficult problem assosiated with stem cell's treatment is to direct them into unhealthy organ. If we just inject them into blood they will stucked in all organs. So if we want to treat a heart, we should direct stem cells into the heart.

However, it was a problem until now. You can not distinguish stem cells from other cells, until you extract them from the ogranism and put into the microscope, of course. Recently scintists from Emory and Georgia Tech discovered a way to direct stem cells using a magnets.

They coated magnetized iron oxide nanoparticle with polyethylene glycol that protects the cell from damage. The particles become stucked into cell's lysosome. After that scientists use a magnet which direct cells to the tail of the mouse. Then procedure was done, they detect the cells at the tail of the animal.

Such method can be a next step which will improve efficiency of stem cell treatment.

Natalia Landázuri, Sheng Tong, Jin Suo, Giji Joseph, Daiana Weiss, Diane J. Sutcliffe, Don P. Giddens, Gang Bao, W. Robert Taylor. Magnetic Targeting of Human Mesenchymal Stem Cells with Internalized Superparamagnetic Iron Oxide NanoparticlesSmall, 2013; DOI: 10.1002/smll.201300570




Artifitial peroxisome could prevent cellular senecsence.

A lot of scintists believe that one of main reasons for cellular senecsence is oxidative stress. Active forms of oxigen, like hydroxyl ion or single oxygen, could appear in the cell during mitochondria's work and as side product of a lot of other cellular processes. If you want to read more, just read a book....

There are also organels in cell that can utilize active forms of oxygen. These organels are called peroxisomes, they containe enzymes able to convert active forms of oxigen into safe O2 and water. Scientist from University of Basel, Switzerland managed to create artificial peroxisomes,a polymeric capsules with channels which allow chemicals and compounds to get in and out of the peroxisome.


Artifical peroxisomes successfuly helped to utilize active forms of oxygen and they could effectivly prevent cellular senescense.

Aiding Nature’s Organelles: Artificial Peroxisomes Play Their Role

Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
Nano Lett., 2013, 13 (6), pp 2875–2883, DOI: 10.1021/nl401215n


 

New method for treat Daun's syndrome.

The most famous genetic decease is Daun's syndrome. It is caused by tripsony of 21th chromosome. If you are a healthy person, you have two copies of this chromosome, and if you have three copies of the chromosome, you have a trisomy and you are ill. So all the problem is in extra chromosome.

Team of biologies from University of Massachusetts Medical School in Worcester discovered a new way to treat Daun's syndrome. The key for the treatment is the fact that all women have... extra chromosome too! As you know, all women care XX genotpe, and all men care XY genotpe. Thus, as soon as all men live successfuly with only 1 chromosome, women have one extra chromosome. However, women are not ill because there is a gene, called XIST, which inactivates one X chromosome by covering it by special RNA.


What scientists do is to put XIST into one of 21th chromosome and made it inactive. The experiment was conducted on iPSC. This method will allow to treat other chromosomic desease in future.

Jiang, J. et alNature http://dx.doi.org/10.1038/nature12394 (2013).




Saturday 13 July 2013

eEF2K

In my opinion, the most difficult problem associated with cancer is the fact that treatment, that can effectively kill cancer cells, also kills healthy cells. We use a nuclear weapon instead of gun to kill a bear.

On the other hand, there are some drugs able to target attack cancer cells. However, this drugs are not a cure too. Their action is based on genes and proteins that overexpressed in cancer cells, but not in healthy cells. Yes, it is an exit from the situation, but not effective enought that we could say that we can cure cancer.

But recently scientists from University of Southampton became one step closer to achievment of this difficult goal. Because of frequent process of division, cancer cells require more oxygen and nutrients and thus they starving more often than usual cells. Prosessor Cris Proud discovered that there is a cellular protein, eEF2K, that allows cancel to survive starvation, but normal cells do not require it to survive. Professor Proud and the team are now working with other labs, including pharmaceutical companies, to develop and test drugs that block eEF2K, which could potentially be used to treat cancer in the future.



The smarter you are, the longer you will be mentally health.

Do you read books? Do you write a lot of letters? Do you learn new words?Positive answers on this questions could affect your entire life, especially retirement.

Robert S. Wilson, PhD, with Rush University Medical Center in Chicago conducted the experiment aimed at studing the bond between cognitive abilities of eldery people and their everyday activities. During six years experimentators were collecting answers for questions similar to those in the beginning of the post from 294 people. Also they studied brains of people after their death.

Scientists revealed that people who participated in mentally stimulating activities both early and late in life had a slower rate (32%) of decline in memory compared to those who did not participate in such activities across their lifetime.

So do you want to be mentaly heath at the end of your life? Be smart! Read books! And, by the way, smart is the new sexy ;-)


Sourse: R. S. Wilson, P. A. Boyle, L. Yu, L. L. Barnes, J. A. Schneider, D. A. Bennett. Life-span cognitive activity, neuropathologic burden, and cognitive agingNeurology, 2013; DOI: 10.1212/WNL.0b013e31829c5e8a


Monday 8 July 2013

SciAm Challenge

Are you a scientists?

Do you want to change the world?

Do you want to win a prise?

If yes, this challenge is for you! Take a part in the Scientific American Challenge and win the prise!




Learn more

Brain's epigenetics

The brain is the most complicated system in our universe, but now we become one step close to the key of the brain’s riddle. 

Epigenetics is the study of changes in gene expression or cellular phenotype, caused by mechanisms other than changes in the underlying DNA sequence (Wikipedia). So changes in the epigenome, including chemical modifications of DNA, can act as an extra layer of information and play important role in information’s storage at our brain. 

In the major part of cases methylation of DNA occurs in GC rich regions of DNA. Otherwise, there are some examples of non-GC methylation which were found in embryonic stem cells and iPSC before this cells undergo differentiation. But recently team of Joseph R. Ecker, professor and director of Salk's Genomic Analysis Laboratory, found that such methylation take place in brain cells even after differentiation. Ecker’s team found that non-CG methylation accumulates in neurons through early childhood and adolescence, and becomes the dominant form of DNA methylation in mature human neurons.

 A lot of scientists supposed that many neurodegenerative diseases connected with postdifferetation development of the brain cells, so this discovery could be the key to treat.


 Source





One advantage of the eldery people.

All of us used to think that the greater age, the bigger problems with immune system we have.  A major percent of influence-related deaths occurs between people above 65. Everything of this is true then we speak about some simple infection like bird flu.

However, situation changes when a person has a serious virus, like N1H1 flu. Scientists revealed that people above 65 suffered from this virus with lower frequency than other groups of people. It was suggested that such phenomenon take place because of some sort build-in immunity associated with specific capable to interfere with flu proteins.

Thus, next time you will have a possibility to get some terrible virus, let’s ask your grandparents to some saliva or blood in order to make a vaccine. 

 Resource

Friday 5 July 2013

The rejuvenation of heart is possible....thought the brain!

        The circadian patterns in mammals mostly follow 24-hours cycle. A lot of studies show that maintaining circadian cycle is very important to the health, disruption of it could lead to obesity and even diabetis. Scientists also reported about direct correlation of circadian cycle and lifespan. The more robust circadian cycle is, the longer life you live. This link direct scientists to find gene-manager of the circadian cycle .

          SIRT1 is known as regulator of cell's responce to stress, hormone's level and a lot of other signaling pathways, that help cell to stay healthy. Leonard Guarente from MIT conducted an experiment on mice. He studied three gpoups of mice. The first one had lack in SIRT1 expression, the second one was a group with nornal SIRT1's level of expression, and the third one overexpressed the gene. Level of gene expression was observed in the brain. The experiment revialed that mice with larger amount of gene's copies do not suffer from age-dependent decline in circadian cycle. 

       Thus it becomes possible to prevent age-related deseases by using SIRT1 enhancers. Unfortunately, in order to be helpfull, the drug should be directed to the brain and nowadays there is no such medicine that could overcome blood-brain barrier




Thursday 4 July 2013

Japan scientists managed to grow human liver in mice

Scientists from Yakohama City University managed to grow human liver in mice. Of course, this liver is not human-sized, but its structure and functions are the same to human liver.

The liver was cultivated from three types of human cells. First, iPSC from human skin were made. The genes responsible for growth and proliferation of liver cells were activated. Second, the endothelial cells from grow umbilical cord serum were added to generate blood vessels. The third component of the mixture was mesenchimal cells, which are origins of bones and fat.

Once Takanori Takebe observed that cells, cultivated together, organazing into 3D structures. After that a lot of attemts were made to achive ideal prorortion of cells.

Little livers grew up to 4 mm in diameter, after that they were injected into mouse, where liver starts to secrete proteins. Moreover, this cell transplants formed their own vessels and connected to mouse's vessels system.

Thus, the main problem of organ' sgrowing seems to be solved.



Nature

Tuesday 2 July 2013

Reform of Russian Academy of Science

In recent decade the Russian parliament have a trend to make various reforms.

I am not very interesting in politics, so the first reform, that I remember, was an education reform. According  to it Russian (USSR) education system should become similar to the educational systems of Europe ant the USA. I think, each of systems has its own advantages and disadvantages, however, I prefer to study in USSR system, because it does not limit an imagination and creativity of children, but no one asked me or my parents to chose the system.In my opinion, this reform will make russian children stupid.

And now, they decided to reform Russian Academy of Science.  I will not give here a lot of details, but a lot of branches of RAS will be eliminated and  RAS will be deprived of its property. This will allow to sold RAS buildings, that cost a lot of money, and fire a lot of scientists. So, with great confidence I can conclude, that RAS will die soon. =(((((

The only way you can help Russian scientists to survive is to write an open letter to Russian President, Vladimir Putin. Please, write!