Tag Archives: Medicine

Human Genes Cannot Be Patented, Says A Landmark US Supreme Court Ruling

A Supreme Court ruling may change the landscape of genetic research forever. The US Supreme Court ruled that human genes cannot be patented, in a landmark hearing giving a huge victory to the American Civil Liberties Union (ACLU) while disheartening Myriad Genetics. The issue was the BRCA genes, the mutations on which are believed to be responsible for increasing the susceptibility to breast cancer.

The Contention

Myriad Genetics had claimed patent over this gene, claiming to have ‘invented’ this gene, which meant that all treatments and even detection of the BRCA gene would entail a royalty to Myriad. This would’ve raised the costs of detection, costs and treatment of breast cancer significantly. In a beautiful moment when calm commonsense prevailed, the Supreme Court struck down the ‘invention’ claim by saying:

Myriad did not create anything. To be sure, it found an important and useful gene, but separating that gene from its surrounding genetic material is not an act of invention… Myriad found the location of the BRCA1 and BRCA2 genes, but that discovery, by itself, does not render the BRCA genes … patent eligible.

Courtesy: medscape.com
Courtesy: medscape.com

The Consequences

This, of course, means huge losses for the pharmaceutical industries, but it’s the cancer patients who stand to benefit in the long run. The costs of detection tests and their subsequent treatment would come down, as no one company would have the monopoly on the technology and research. As it should be!

Myriad’s defence even involved a ludicrous ‘baseball’ argument, in which they argued that the “baseball bat doesn’t exist until it is isolated from a tree. But that’s still the product of human invention to decide where to begin the bat and where to end the bat”. This analogy fails on many levels and the court noted that merely deciding the start and end points of a gene sequence doesn’t deserve a patent. Official ruling said:

The baseball bat is quite different. You don’t look at a tree and say, well, I’ve cut a branch here and cut it here and all of a sudden I’ve got a baseball bat. You have to invent it.

However, Myriad did get part of the pie, when the court ruled that the Myriad can have its patent on the invention of the cDNA – complementary DNA – which is actually a synthetic form of DNA.

“The lab technician unquestionably creates something new when cDNA is made,” said the court.

The ruling here: http://www.aclu.org/free-speech-technology-and-liberty-womens-rights/association-molecular-pathology-v-myriad-genetics-0

Reported: The First Known Case of a Child Being Cured of HIV

HIV might have finally met its match. We report the first documented case of a child being cured of HIV after antiretroviral therapy. Dr. Deborah Persaud of John Hopkins University presented this remarkable case yesterday at the 2013 Conference on Retroviruses and Opportunistic Infections, Atlanta, Georgia. The breakthrough was confirmed by various ultra-sensitive test on the child, all coming out negative for the presence of the HIV viral load.

Scanning Electron Micrograph of an HIV attacking a live cell.

The child was born HIV positive, since the mother was also HIV positive. At the age of 2 years, the child in Mississippi was diagnosed with the deadly virus and immediately put on antiretrovirals. This therapy continued for 18 months. After five more months, during which the child was off treatment, the child was tested and the absence of HIV was confirmed via highly sensitive tests. Dr. Persaud said that it was beyond any doubt that the child showed no signs of being HIV positive.

The treatment for HIV depends crucially on the patient’s immune system makeup. Also, an infant’s immune system differs from that of an adult. Scientists want to study the individual’s immune system, especially since the treatment of the patient happened via only very cheap antiretroviral therapy, rather than expensive treatment. No one is really sure how this cure happened.

This is only the second documented case of an HIV cure, the first one being the famous ‘Berlin Patient’, Timothy Ray Brown. He has founded his own AIDS Foundation, the Timothy Ray Brown Foundation, dedicated exclusively to finding a cure for the deadly disease.

However, the Ray Brown case is quite different from this. Even though, the Ray Brown involved a longish course of antiretrovirals, there was a diagnosis of myeloid leukemia in case of Ray Brown. His heamatologist, Dr. Gero Hutter, make a stem-cell bone-marrow transplant from a doner who had a very rare HIV immunity called the CCR5 mutation. A few months later, there was no active HIV viral load in his body.

Nothing nearly as drastic as a stem-cell bone-marrow implant was done in this present case. And that makes this case all the more special.

More info here: http://www.nytimes.com/2013/03/04/health/for-first-time-baby-cured-of-hiv-doctors-say.html

Nobel Prize in Medicine Explained

So the Nobel Prize in Physiology and Medicine for 2012 has been announced, but what have the deserving winners done anyway? Here’s a look at the defining achievements that have cemented their place in history.

What’s the Big Deal With Stem Cells?

Sir John Gurdon from Cambridge and Dr. Shinya Yamanaka from Kyoto University have won the prize for their work on induced pluripotent stem cells (IPS), and every biologist has greeted this news with a cheer. Every cell in our body is specialized to perform its own task; that’s why your food goes into your stomach and air into your lungs. However, every cell in our body arises from one single cell. How does this division of labor occur? At some stage of development in the womb, cells undergo a process called ‘differentiation’, which is what tells the cells what functions they will be restricted to performing. What we call ‘stem cells’ are essentially undifferentiated cells, which are enormously powerful simply because they can turn into any type of tissue we want!

Sir John B Gurdon, who first proved that differentiation could be reversed. [Image Credit: nobelprize.org]

This differentiation was thought to be one-directional. In 1962, Sir John Gurdon showed that the reverse of the ‘differentiation’ process could be achieved. Cells from a tissue like the skin could be reversed to form ‘stem cells’ that could in turn turn into any type of tissue. He took out the nucleus of an adult frog and injected it into an egg cell of a tadpole (from which the DNA-containing nucleus had been removed). This embryo then grew into a live tadpole, showing that ‘adult DNA’ really could become ‘immature’ again.

Dr. Shinya Yamanaka converted skin cells from mice into embryos that could grow into adult mice. [Image Credit: nobelprizeorg]
Dr. Shinya Yamanaka, in 2006, concocted an actual recipe for this reverse differentiation, and produced IPS cells from the skin cells of mice in this seminal paper. He identified 4 genes that could convert these skin cells into immature yet all-powerful stem cells.

These cells have huge potential in both medicine and research. Brain cells, for example, are notoriously difficult to isolate. Thanks to their discovery, we can produce IPS cells and culture brain cells instead of having to isolate them. While the direct applications to medicine are not yet on the horizon, this technology does hold promises for the future.

 

Deadly Ebola Virus Outbreak Confirmed in Uganda; 14 Dead Till Now

It is mysterious, it kills quickly and it spreads fear and panic. Western Uganda is seeing an outbreak of the deadly Ebola virus, reporting at least 14 dead till yesterday. The deadly virus is seemingly making a comeback to the African country and it has taken doctors quite a while to pin it down going by the symptoms induced in the patients. This is bad news, since this suggests that the recent attack is due to some new strain, unknown or non-existent till now. This means that no medical record or research exists on this particular strain.

Small strips of death – the Ebola virus (courtesy: BBC News)

The center of the outbreak

The Kibaale district, lying in the center of western Uganda, has been center of the outbreak with people suffering from a mysterious illness in recent weeks. The cause was unknown and many people have left home fearing a disease caused by bad luck or evil spirits. It turns out that reality is worse than that.

The Ebola was confirmed just last night. By today morning, 20 cases have been reported and 14 have died, including a four-month old baby. With no known cure or vaccines, the disease is expected to spread really fast.

Symptoms

Ebola virus causes haemorrhagic fever and kills quickly. The CDC says that the Ebola disease is characterised by “fever, headache, joint and muscle aches, sore throat, and weakness, followed by diarrhoea, vomiting, and stomach pain. A rash, red eyes, hiccups and internal and external bleeding may be seen in some patients”.

The scariest part is how the disease is transmitted. It may be transmitted via bodily secretions and blood. Even the dead is a potential risk. Ebola viruses survive for a long time in the body of the dead after the actual death and funerals can act as mass infecting grounds.

The Medical Organisations

Ugandan officials have been asking the public to keep calm. But that optimism isn’t necessarily shared by all medical organisations. The Center for Disease Control (CDC) are looking for a way to contain this newest attack, which brings back memories of the deadly attack in 2000, which officially left 225 people dead. More recently, a relatively minor outbreak in 2007 left about 40 dead, officially.

The authorities are fearing an epidemic. The spread of any deadly disease is facilitated by time. As more people get infected, the chances of infection rises and the number of people taking care of the infected – the doctors and nurses – also thins out, making it easier for the disease to grow even deadlier.

Diseases sever human relations. As nurses and doctors rightly fear for their lives, the number of patients increases. With diseases like this, the best hope is containment. As callous as it sounds, all we can really do is let the disease die out within a small territory.

Artificial Vein Created Out of Stem Cells Saves A 10-Year Old Girl’s Life

The stem cell revolution is doing exactly what had been predicted of it – saving lives of patients with rare diseases. A 10-year old Swedish girl, suffering from a blockage of a vein in the liver (medically ‘extrahepatic portal vein blockage’), is the first recipient of a major vein replacement using stem cells.

Stem Cell (Source: Wikimedia Commons)

Stem Cells are cells capable of specializing into cells with very specific functions. Stem cells can thus be used to regenerate any part of the body, proving invaluable to treatment of cancer – or even vein blockages.

The Operation

Associated Press reported the story saying that the vein replacement using stem cells was the alternative to a liver transplant. A 9-cm vein was taken from a dead man and stripped of all living cells. Only the protein remained, devoid of any genetic information. This was then grafted with the stem cells extracted and harvested from the girl’s bone marrow. The graft became a vein exactly identical to one made by the girl’s body within a period of two weeks of so. This was planted into the patients body after removing the offending blocked vein.

No post-operative complications

There have been no complications accompanying the surgery. The biggest fear remains that of rejection. If the body’s immune system recognises the grafted vein as a foreign object, it will attack it, causing severe complications and even death. This happens during the first few days immediately after surgery and immunosupressant are prescribed to prevent this hyperactivity of the immune system.

In this present case, no immunosuppression was required. A liver transplant requires lifelong dependance on immunosuppresants.

The doctors measured the blood flow through the new vein and found it to be normal. This was confirmed using ultrasound.

The whole operation has been funded by the Swedish government.

The report: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)60633-3/fulltext

Preserved Blood From 5300 Year Old Iceman Is World’s Oldest!

An open wound on a corpse is like a time machine – especially if the corpse is 5300 years old. Meet the most famous 5300 year old, his body preserved in as pristine a condition as this much time will allow – Oetzi. He was found in the Italian Alps, on the Oetz valley (and thus his name) in 1991 and since then has aroused considerable interest because of his well-preserved features.

Getting details

Scientists have been able to figure out that Oetzi died from a spear wound. He probably died soon after the strike and not from an infection from the wound. An axe and scattered arrow fragments lay around him. Some have even reconstructed Oetzi’s face, giving him a grizzly look of a stern, but aging hunter. Brown eyes were a figment of imagination, but they look good on him. He is the ultimate prehistoric fashion model.

Oetzi - probably

So well preserved is Oetzi that scientists have even been able to extract valuable DNA samples from whatever remains of his skin. Nothing useful could be concluded. They have also extracted mitochondrial DNA from his intestines. Mitochondria are small bodies living within cells. They contain their own DNA, apart from the nuclear DNA. Hereditary features are caused by nuclear DNA – the ‘familiar one’ – while the mitochondrial DNA remains inactive. It can only be passed down through the maternal line.

The DNA gave some tantalizing hints as to where Oetzi might have hailed from or what his biological ancestry might have been. Scientists speculate that he might be East European, but they aren’t very sure. Among other things, scientists speculate that he might have been infertile!

The preserved remains.

The blood

The latest in the Oetzi story features his blood. Blood cells degrade rather rapidly, but Oetzi even has blood preserved underneath his skin. This marks the oldest red blood cells ever recorded! Researchers at the Center for Smart Interfaces, University of Darmstadt, Germany, found that atomic force microscopy revealed minute amounts of blood in thin slices of tissue.

The RBC's as seen under an AFM. (Courtesy: BBC)

Atomic force microscopy relies on mapping out the atomic topography of a surface using a tiny atomically sharp metal tip. The concave shape of red blood cells clearly shows up (figure above)!

But something is anomalous – the fibrin levels are low. Fibrin helps blood to clot. It is found in very high quantities in fresh wounds. The fact that the blood will be preserved but not the fibrin seems far-fetched, so maybe Oetzi died slowly, due to a bleed or an infection rather than directly from a spear wound.

The dead do speak.

Alarm Bells Ring As Eight Patients Are Confirmed With TB Resistant To All Known TB Drugs

The ticking time bomb is giving signals that it is coming to the end of its countdown. The National Tuberculosis Institute (NTI), Bangalore, has confirmed eight cases all reporting TB germs resistant to all known TB drugs. A confirmatory notice has also been sent to the Central TB Division or CTD, New Delhi.

Twelve patients with symptoms of Tuberculosis (TB) were admitted to the Hinduja hospital on January 6th. Doctors soon declared them infected with Totally Drug Resistant TB (TDR-TB). Three out of the 12 died soon after. Sputum samples from all the 12 were sent for testing. Eight came out positive for a strain more resistant than earlier thought.

Triggering the time-bomb

Resistance to drugs generally results from the overuse of antibiotics. It’s simple evolution, really. Few of a population of TB germs may develop a genetic factor enabling it to resist a drug administered on the patient, say drug A. These few are the only surviving members of the population. Now, these multiply, giving rise to the next generation of germs resistant to this particular drug. When it infects another patient, a new drug – say drug B – is needed. Some members of this new population can then develop resistance to drug B, while retaining its resistance to drug A. Over prescription of medicines known to work on TB germs accelerates this process and very soon we get TB germs resistant to multiple drugs. This is what is referred to as Multi-Drug Resistant TB (MDR-TB).

TDR-TB refers to TB which are resistant to first line drugs. First line drugs are drugs proven to work against the bacteria, with the least amount of side-effects. There is a second line, which may not be as effective, or may produce more side-effects, or maybe not as well clinically tested as first line drugs. Second line drugs are used when first line ones fail. MDR-TB is resistant to many second line drugs as well.

Even worse

Eight of the Hinduja patients were infected with TB that showed resistance to both first and second-line drugs, making it Extremely Drug Resistant TB (XXDR-TB). However, WHO doesn’t recognize this classification. The case has been documented on the Directly Observable Treatment Shortcourse Plus (DOTS+) log. Doctors are still to figure out the line of treatment for these eight patients.

The TB timebomb is ticking… maybe beyond our control now!

Scientists Create Artificial DNA, Observe Darwinian Evolution In Them

The very basis of life can now be created in the laboratory and it’s not unique. What more this artificial genetic material can mingle easily with the real thing, even evolving as the real thing does. The creation of artificial DNA and RNA strands have been reported by Pinheiro et al. They have even observed their evolution.

A new class of molecules, very similar, but not quite

Till now, the only molecules known to be capable of undergoing Darwinian evolution were RNA and DNA, but this discovery suggests that there might be a lot more candidates that fit the bill. There is really no “Goldilocks solution”.
DNA (or RNA) has a double helical structure, meaning that it looks like two strips of paper wound around each other in a helical fashion. The structure is ladder like – with each rung consisting of two nucleotide bases held together by sugar molecules.

The Structure of DNA. The A,C,G and T label the nucleotides.

Pinheiro’s group retained the nucleotides of DNA – the Adenine, Guanine, Cytosine and Thymine (or Uracil, in case of RNA) – but altered the sugars that bind these nucleotides together. In this way, he created XNA, with the ‘X’ standing for the sugar used. DNA, or deoxyribonucleic acid, uses deoxyribose as the sugar, while RNA, or ribonucleic acid, uses ribose as the sugar. But these use different sugars, thus giving them different names. For example, arabinose is the sugar in ANA, flourarabinose in FANA, threose in TNA, a “locked” ribose in LNA and a cyclohexane in CeNA.

Retention and copying of information

Here is the crucial bit: Even though the sugar bases were changed, the nucleobases being the same meant that these artificial XNA’s behaved exactly like the DNA found naturally. They could even pair up with the naturally found DNA.

Here is another crucial bit of the story: When DNA or RNA create copies of themselves, they use helper molecules called polymerases. These polymerases separate the two chains of the double helix structure, read the sequence of letters, helps in the formation of a similar chain, zips the whole thing back again and creates a new DNA molecule, all in this process called transcription. Evolution – or small genetic changes in the DNA structure – happens the copy of the DNA is not exactly like its parent. Environmental factors then ‘selects’ the more competitive versions of these modified DNA molecules and this helps them create more copies of themselves. Thus, a trait is acquired and another is lost.

Building your own genetic copy machines

The team had to build separate polymerase molecules to help transcribe the XNA’s. They were able to, thus, transcribe the code of the synthetic DNA to natural DNA and then back to the synthetic DNA. The XNA’s thus formed are just as immune or vulnerable to the original DNA. XNA’s must also be able to proliferate just like DNA does without any external help, in a process called amplification. Amplification was noticed with the artificial polymerases and the XNA’s. This is important, otherwise the XNA’s won’t be able to undergo Darwinian evolution like DNA.

In one of the experiments, a control was set up. The factors were controlled such that if the XNA did not ‘cling on’ to a particular protein, it would be washed away. Pretty soon more and more XNAs began developing this trait. This again proves that the two very important traits of inheritance through genetics and selection – information storage with high fidelity of copying and propagation of mutations – are not characteristics of just DNA or RNA. This gives the grand possibility of finding a whole new structure of biochemistry.

Maybe novel forms of life are not that far away in the future!

Study and the technical paper here: http://www.sciencemag.org/content/336/6079/341.abstract

Eureka? Stem Cells Breakthrough Allows a Possible AIDS Cure

Stem Cells are the way forward for medicine and this is another confirmation of that. Just ahead of the upcoming World AIDS day, comes a wonderful piece of news – stem cells can be used to cure AIDS. This has been demonstrated the case of mice.

The T-cells

There are specific cells in the body’s defense system which can recognize HIV cells and kill HIV-infected cells, called cytotoxic T-lymphocytes. However, because HIV prevents the immune system from proliferating the WBC’s (white blood corpuscles- the soldier cells) during an infection, the T-cells aren’t produced in sufficient quantities. Now, scientists are using blood stem cells and ‘programming’ them to form mature T-corpuscles in sufficient number to attack the infection properly.

The tests were done in a lab in California University and the experiment subject was a humanized mouse. By humanized, it simply means that the progress of the HIV infection in the mouse mimics the progress in humans.

The experiment

The experimental subjects were observed for progress. Blood tests were done on the second week and sixth week. The scientists found that the T-cell count had increased and the HIV level decreased! Is this the long sought after cure?

Dr. Scott G Kitchen, lead scientist in this study, said:

We believe that this is the first step in developing a more aggressive approach in correcting the defects in the human T cell response that allow HIV to persist in infected people.

There are a lot more drug trials that need to be conducted before this can be thought of as a cure. Further, these have to be tested on human patients and their efficacy measured. The first step is a very promising one. It’s too early to say, but this can be the cure against AIDS.

The study appears here: http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002649

MIT Scientists Pinpoint Location Of Memory; ‘Create’ And Manipulate Memory At Will!!

It’s a dangerous game – playing around with memories – but someone’s got to do it. MIT researchers have just found out where memories are stored – in individual neurons. Not only that, by selectively activating and deactivating certain neurons or group of neurons, the MIT team could either fire or erase certain memories. “Eternal Sunshine of the Spotless Mind” fans might have known this coming for a long time, but this is the first time this kind of manipulation is being made possible.
The team experimented on mice. They drilled a small hole through the skull and then aimed their lasers at very specific areas in the brain. So that the neurons responded to light signals, the researchers used optogenetically modified neurons. This allowed the scientists to play around with thoughts using electric signals as well as laser light.
The hippocampus of a mouse (Courtesy: MIT, Nikon Small World Gallery)

Manipulating Memory

One of the demonstrations involved creating a feeling of fear in the mice. The scientists triggered off a very specific area of the hippocampus of the brain using electric signals. This created a fear memory! The team then fired off lasers in order to activate this memory centre and immediately found that the mouse had gone into a “defensive, immobile crouch”, paralysed by fear. However, we still don’t know what the exact memory was; we just know its nature.
Just to ram home the point: scientists can pinpoint certain regions of the brain and create memories of very specific emotions. They can then ‘replay’ these memories, forcing the individual to react to these memories. Till now, the emotions need to be very simple! Remember that these memories can be very false! However, we still cannot manufacture specific detailed filled memories.

Questions…

Though these experiments have been done only on mice, human brains are not too different, except that it is a lot more complicated. Scientists think that these can be replicated in humans, but no human subjects have been used for experiment, and none will be used in the near future.
This answers the old question of what memories are in the brain. They are not merely concepts – they are physical objects, represented by individual neurons. The next question to be answered is this: how are memories formed? Also, why do we remember a scene like we do, rather than in greater detail? Also, how are memories encoded? Is it possible to create a computer program to bestow a certain set of memories to an individual? The MIT team may be close to answering that.
Memories are more mundane than one might have thought, proves the MIT team. Remember that!
More info: http://www.mit.edu/newsoffice/2012/conjuring-memories-artificially-0322.html