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Researchers say that the blockbuster movie Inception is not a complete Hollywood fantasy.

Even tough the word definition of dream is something like “a series of mental images and emotions occurring during sleep” the actual scientific definition is still a matter of much debate. A few people will define it as a REM (rapid eye movement) sleep experience which actually the research doesn’t support. There are some interesting things going on in the brain during REM. REM is generally the only time during sleep that most of the cortex is pretty much as active as it is when we’re awake. The rhythmic brain stem activity during this phase wakes the cortex up and then cortex carries out some ordered and meaningful functions. This gives the impression that one is dreaming.

During dreams there are certain regions which are otherwise inactive or little activate, now in an activated or hyperactivated state. The reverse is also true.  Scientists say that we can use dreams to solve a problem. Here is how it works (but not always):

f you want to problem-solve in a dream, you should first of all think of the problem before bed, and if it lends itself to an image, hold it in your mind and let it be the last thing in your mind before falling asleep. For extra credit assemble something on your bedside table that makes an image of the problem. If it’s a personal problem, it might be the person you have the conflict with. If you’re an artist, it might be a blank canvas. If you’re a scientist, the device you’re working on that’s half assembled or a mathematical proof you’ve been writing through versions of.

Equally important, don’t jump out of bed when you wake up—almost half of dream content is lost if you get distracted. Lie there, don’t do anything else. If you don’t recall a dream immediately, see if you feel a particular emotion—the whole dream would come flooding back.

Studies also reveals that lucid dreaming– dreaming that we are dreaming, can also be enhanced by practice. By reminding yourself you want to just as you’re falling asleep, either as a verbal statement or idea: “Tonight when I dream, I want to realize I’m dreaming.” This is the most important thing, the researchers say other than getting enough sleep.

There are evidences that suggest even one can control the dream of other person, but the extend of which is still unknown.

The study of sleep and dreams combines the knowledge of biology and psychology. Through a combination of these fields, researches are going on in various parts of the world to unlock some of the biggest mysteries of human mind.

References:

1. Scientific American July 29, 2010

2. Wikipedia

3. Some more websites

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Two studies published today in the journal Genes & Development on August 1, 2010 gives the notion that cell death or apoptosis is not an absolute answer to getting rid of cancer cells. It turns out that cell death can actually sometimes spur the tumor growth.

The recent papers dealt with the role of a protein called PUMA, which triggers cell death in response to damaged DNA. PUMA is activated by the well-known tumour-suppressor protein p53, sometimes called ‘the guardian of the genome’. Without PUMA P53 cannot flip the cell-suicide ‘switching’.  P53 senses the DNA damage and sends signals that activate PUMA, a potent proapoptotic BH3-only protein that inhibits all antiapoptotic proteins and activate the mitochondrial cytochrome C release leading to cell death.

Considering this in mind, the researchers developed mice that lack PUMA and then subjected those mice to DNA-damaging radiation. The researchers expected the animals to quickly develop cancer and die. But to their surprise the mice that lacked PUMA fared better than normal laboratory mice.

So whats happening? The researchers found out that PUMA producing mice activated cell death in response to DNA-damaging radiations, leading to creation of holes, that are now filled up by stem cells. But some of the stem cells retained the mutations caused to them by the radiation damage and they started to multiply causing cancers.

They are not sure if this works in humans also.But the results, if confirmed in humans, could have implications for cancer therapies now under development: some that aim to stimulate programmed cell death could actually stimulate cancer as well.

Refereces:

1. Nature news: http://www.nature.com/news/2010/100731/full/news.2010.383.html?s=news_rss

2. PUMA, a potent killer with or without p53- J Yu and L Zhang http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2860432/


In a paper published today in Science (Science, 329, 559; 2010 doi:10.1126/science.1187936), scientist from Biofuels startup LS9 announced the identification of genes from Cyanobacteria which are involved in biosynthesis pathway that leads to the production of Alkanes, the major constituents of gasoline, diesel, and jet fuel.

For a long time it was known that Alkanes, the major constituents of gasoline, diesel, and jet fuel are naturally produced by diverse species; however, the genetics and biochemistry behind this biology have remained elusive. The Ls9 scientists pinpointed the exact mechanism and the genes involved in this pathway. They identified that the pathway consits of an acyl–acyl carrier protein reductase and an aldehyde decarbonylase, which together convert intermediates of fatty acid metabolism to alkanes and alkenes.

After this they expressed theses genes in E.coli and found out that a mixture of alkanes and alkenes are secreted. These genes and enzymes can be now used for direct, one-step conversion of feedstock to fuel.

Though the company claim the cost of their Biodiseal around $100 which is a bit higher than crude ($75), they are hoping to cut down the cost to $50 by 2012.

But there are still doubts as to whether they can use the processes to scale up the production of Biofuel cheaply enough to complete with oil.

Only time will tell the answer.


iPS cells could be used as a therapy for many genetic disorders by following three steps-Rewind,Reprogram and Replace.

The scientists are excited about a type of cells called Induced Pluripotent Stem Cells or iPS cells that can give rise to any part of the body from any type of cells. iPS cells are the adult or somatic cells that are reprogramed to enter into a Embryonic Stem Cells-like state by the integration of up to four DNA-transcription factors. The groundbreaking works were first carried out  in 2007 by two groups headed by James Thompson at the University of Wisconsin-Madison and Shinya Yamanaka at Kyoto University in Japan who described methods to reprogram adult human cells to a pluripotent state. In December of 2007, George Daley, of Harvard Medical School in Boston, Massachusetts, and his colleagues also demonstrated iPS cells could be generated from a variety of adult cells.

According to Thomas Zwaka from the Baylor College of Medicine, “the initial idea was to generate iPS cells from any somatic cells“. This is very important because the other method of generating Pluripotent stem cells was to extract it from the early embryo and this created many political, ethical issues. Now the scientists can convert any cell in the body to a pluripotent cell. The other motive was to generate the pluripotent cells that matches the patient genetically. There were problems regarding mismatch of patient’s genetic identity and the cells obtained from embryonic stem cells. The ability to induce pluripotency allows the scientists to engineer cells that are genetically identical to those cells in the patient’s body.

The therapeutic maneuver include the isolation of any cells types form a patient with, say some genetic disorder, reprogram those cells and then put the new cells back into the patient. These steps requires some genetic information that must be supplied to the cell. First one converts the somatic cell into pluripotent cell, the second one corrects the genetic defect and the third one turns the cells into a new cell type that can replace the diseased cell type in the patient. So the motto is “Rewind,Reprogram and Replace”

The three steps mentioned above also present the scientists with many technical difficulties. The first step, converting the somatic cell in to a pluripotent stem cell is a much explored area. It is now considered that at lest 4 genes are required to push the cell into a pluripotent state. It is here the work of Yamanaka becomes important. His group published the first of these results in 2006. But actually he did not use the reprogramming factor per se, but some factors that can activate a cascade of downstream of signaling events that ultimately activates a reprogramming factor.

The reprogramming factors are mainly transcriptional factors that are otherwise remain silent in the adult cells but are crucial for induction of pluripotency. These factors when active will bind to and transcribe their target genes, most of which are inactive i an adult cell. Some of the very important transcriptional factors that are essential for induction of pluripotency includes Oct 3/4 and the Sox family.The Klf family and myc family of transcriptional factors are shown to increase the induction when present.

The next step is gene targeting or correcting the defective gene by replacing it with the normal gene. This step should be precise that no change is made elsewhere in the genome or otherwise there will be mutations. The current method uses some vectors that are made to harbor the desired genes and then these vectors are used to transfect the cells. The vectors used can be lentiviral or retroviral which have a high transfection efficiency. But, these vectors have the ability to integrate in to genome and can cause cancers if they happen to integrate near,say a gene involved in cell cycle regulation or control of apoptosis. Adeno Associated Viruses or AAVs that integrate in to genome much lesser than the retroviruses are used more frequently nowadays.

So everything is set and now you can use this as a therapy, isn’t it? No,wait, the researchers say that there are no intentions to clinically test this that soon because there are more things yet to be sure of. Another factor that should be considered is what happens if something go wrong with the cells and they start to grow uncontrollably. How do we remove them? Scientists says that no method will be of 100 percent help if this happens and the best thing is to prevent such an incidence than waiting to cure it. Prevention is better than cure!

The field is still young and the use of this as a therapy is currently way off. But with more and more scientists daring to come to the field and grants are given in the right way, we can hope that sooner or later the works are going to be available not only on the bench but also in bedside too.


Yes..the wait is over for Craig Venter and his team when the 15 year-long pursuit of making the first synthetic cell came to an end in the month of May 2010. This is one of the milestones in the history of synthetic biology and in the field of science itself. Craig venter and colleagues of his J Craig Venter Institute has again proved the conventional wisdom wrong by completing such a daunting project.

Dr.Venter’s JCVI team included  science superstars like Hamilton Smith, Clyde Hutchison,Daniel Gibson, Ph.D and many others.Hamilton Smith, affectionately called “Ham” is the winner of 1978 Nobel Prize in Physiology or Medicine for his work on restriction endonucleases. Clyde Hutchison was a member of the team that sequenced the genome of phiX174 and also has worked extensively on site directed mutagenesis.He missed the 1993 Nobel Prize in chemistry although Micheal smith who worked in the same field got it along with Karry Mullis,the inventer of PCR. Venter and co. used the bioinformatics tool to design the chromosome, synthesized it using the four building blocks of life (the bases Adenine,Guanine,Cytosine and Thymine) and then assembled  it in yeast before transplanting it into a recipient bacterial cell. This bacterial cell was then transformed into a new bacterial species.

The new species they created has some extraordinary elements in its genome including a website!! Watch the Man himself revealing the thrilling story behind this mammoth task.

If you cannot watch this video click HERE


Embryonic stem cell can form any type of tissues when the right conditions are provided

Embryonic stem cells (ES cells) are pluripotent stem cells derived from the inner cell mass of the blastocyst, an early-stage embryo.. Most embryonic stem cells are derived from embryos that develop from eggs that have been fertilized in vitro—in an in vitro fertilization clinic—and then donated for research purposes with informed consent of the donors. They are not derived from eggs fertilized in a woman’s body.
Because of their unique ability to generate so many different kinds of cells, and potential to reside in several areas of the human body, stem cells may eventually establish themselves as a cornerstone of 21st century medicine. Stem cell research has created an entirely new branch of medicine, called Regenerative Medicine. The specialty of this new discipline would be to repair organs or tissues affected or destroyed by age, disease or injury(More!)

Even though this is the case, a lot of controversy exists among the researchers, clinicians, politicians and the public centered on research involving the creation, usage and destruction of human embryos. Most commonly, this controversy focuses on embryonic stem cells. These ethical issues are together called Stem cell controversy. To make the research on stem cell more easy and unambiguous, National Institutes of Health has released some Guidelines on Human Stem Cell Research

Now, you can have your comment on the use of Embryonic stem cells in research. Take the poll!

Toxic Gas, Lifesaver!


Soon, there will be a Hydrogen Sulfide mask just near to an Oxygen mask in most of the hospitals!

Ever thought of waking through the sanitizer-washed floors, past the Dettol-smelling walls of a hospital only to encounter the stench of rotten egg? If you have never thought of this then better be ready for it, because researchers around the world are accumulating evidences for the role and beneficial effects of the nasty, rotten egg smelling Hydrogen Sulfide,H2S.

Hydrogen Sulfide is one of the spiteful smelling gases and it is extremely noxious. This may be the main reason why scientific world never thought of even its presence in human body, although its toxic effects were known for centuries. Even though the physiological role and mechanism of action of other gases like Nitric oxide (NO) and Carbon Monoxide (CO) were known for some time, the discovery of H2S in the body was a surprise to the scientific world. Since then this area has been under hot pursuit.

But, how and why H2S has a role in normal human physiology? To answer this we have to page back to the early days on earth, some 250 million years, when the outlook towards life was very different from now. – Tell Me More Dude!>

The Blind Watchmaker


Dawkins says, if the process of natural selection could play a role as a watchmaker, it will be a blind watchmaker

After a long time I have restarted reading some scientific novels. When I did a brief retrospection into the kinds of books I have ever read, I realized how less scientifically inclined my interests were. I am as ignorant as one who completed with some success his expensive basic studies should never be. This reality had struck me in the past too and relief measures were taken at that time also, but the amplitude of vibrations were too short lived, multiple reasons contributing to this dampening. This time, I start anew, with a strong decision not to allow the negativism to eat my will to work away.

The recent book I am reading is the controversial book from the controversial author. I am reading “The Blind Watchmaker” by Richard Dawkins. He is crazy, I have to admit it or even stress it. He is writing the very same thing most of the biologist knew (whether they accept it or not is up to them), but were never given a second or even a third taught. I have just completed the first chapter of the book. This book takes about the Darwinism, about the very existence of the most complex form of life o this planet or any other planet. This book addresses questions like why we are here and who put us here or put it in another way did someone put us here or that we just happened to be here. Questions go like these, and the answers given in the book are narrative and insightful. He has done a good job of taking pain to explain the things.

In “Explaining the improbable”, the very first chapter of the book, he mainly deals with the complexity of biological things. – Read More>


Fetus can gather information to adapt better to the world it will face..while inside the womb!

This is really interesting..!! The fetus can learn and memorize a few things which makes the life easy once fetus is out of the womb.

Prenatal intelligence and memory were not a part of research until 1970s. Till then fetus was considered as blind and deaf and no body ever imagined that fetus could gather information while in the womb. Even doctors did not care about using anesthetics while dealing with fetuses.

But the insight into the developmental aspects of embryo have changed the whole perspective of these things. There are strong evidences that fetus can hear,smell and even memorize the information it receives.

In an experiment women were allowed to hear an opera song throughout their pregnancy periods. Then, when the researchers analyzed the response of the babies of these women to the same song which their mothers heard during pregnancy researchers were amazed to see that they became calm and relaxed. But the babies of women who never heard the song during their pregnancy started crying or were did not respond at all.

According to one scientist “fetus is bathing in mothers sound”. Scientists analyzed that fetus can View full article »


Human Brain is like an electrical circuit. It can sometimes work wrongly

In any medical sciences, the doctors have historically tried to gain more information about the cause of his or her patient’s illness to prescribe them some form of medication. But when it came to illness like mental and behavioral disorders, the doctors could not find any strong cause for the disorder. Therefor they classified these as just “Mental problems”. But with the advent of the modern biology, neuroscience and genomics, much of the century -old perception of these as psychological disorders is coming to a new turn.

Advancements in the field of neuroscience have shown that all these otherwise called mental problems have a strong biological cause. For example, autism is related to the disordered connections between the neurons in the brain. In recent years huge amount of investments have been put into the field of neurodegenerative disorders like Alzheimer’s Disease and Parkinson’s Disease.  Even though more and more information are generated about these disorders worldwide, the public and scientific community could not tell much on disorders like depression, Obsessive-Compulsive Disorder,and Post Traumatic Stress Disorder. The biological connection or cause of these disorders were hard to pin point because there were no physical destruction of cells visible in the brain of these patients.

Neuroimaging has helped a lot to reveal the biological cause of these disorders. Brian is like an electrical circuit with innumerable connections. The nerve cells, with which the brain is made fires upon its stimulation. These are tightly controlled and too much or too low or too fast ot too slow firing can lead to serious medical conditions,  The above mentioned disorders are now considered to be caused because of the inappropriate functioning of parts of this electric circuit that normally are well synchronized.

Each disorder has a characteristic “electrical circuit” or connections. This picture is slowly emerging now, thanks to the great works of neurobiologists,geneticist and modern biologists.

(For detailed information please see the Scientific American-India April 2010)