An ancient ocean in Mars?

An interesting article was recently published on the journal Nature Geoscience in which the authors report evidence that suggests that Mars had an ocean of water, which covered about one third of its surface.

What is all this evidence about, and why do scientists conclude that there must have been an ocean in mars?

Well, Gaetano Di Achille and Brian Hynek of the University of Colorado in Boulder had been studying high resolution images of the martian surface, and were building a database of all the different valleys and river deltas in mars to propose a way on how they could have been created by water. As geologists explain: When a river flows it erodes rocks and soil; this process over millions of years creates valleys, which have a very significant impact on the landscape. This can be analyzed with current methods and the history of the land can be inferred from the analysis of the available data.
Di Achille and Hynek applied these methods to the Martian surface and they found that these deltas and valleys had very similar elevations and seemed to feed the same body of water; their observations also suggested that a coastline had been formed at these elevations.

A lot of questions still remain, since this new evidence still has a lot to demonstrate before it can really confirm that an ocean existed in mars, 3.5 billion years ago. An indirect analysis does not give the definitive answer to a hypothesis. Experimental trials are the best way to find conclusive evidence. But this new data is encouraging for sending new probes to Mars, and even a manned expedition, that can perform experiments on site.

Finding evidence that demonstrates the existence of an ocean in Mars has very important implications for science, and arises new questions, such as:

What kind of process could cause a huge ocean to completely ‘vanish’ from the face of a planet?

If there was liquid water, did life arise as it did on earth?

And most important, Are there fossils of those possible lifeforms buried in the martian surface?

These aren’t easy questions. But they stimulate new ways of thinking, and the sense of wonder needed to start researching. Perhaps the answers to these questions can give explanation to the different hypotheses that we have about the evolution of our planet, and the evolution of life itself.

An abstract for the letter published in Nature Geoscience can be reached at http://www.nature.com/ngeo/journal/vaop/ncurrent/abs/ngeo891.html

Thank you for reading.

My Research

Sometimes I get asked, “What is your research project about?”

My work sometimes is hard to explain in plain words since I work on a very specific area of research. However I’d like to give an overview of the stuff I do research on.
My main interest is neurosciences and molecular pharmacology. At the moment I am doing research on new treatments for ischemia–reperfusion injury in the brain, caused by stroke or hemorrhage. All my research project is being done at the National Institute of Neurology and Neurosurgery of Mexico.

So, what is this all about?

Well, during stroke, some areas of the brain stop receiving oxygen from the circulation, since the blood flow is stopped. These areas in the brain start compensatory mechanisms, which allow them to survive and at the same time the body tries to restore blood flow so that the functions are restored as soon as possible.
The lack of oxygen is called ischemia and as the cells in the brain try to survive they activate several biochemical mechanisms, one of which activates an enzyme called Inducible Nitric Oxide Synthase (iNOS). This enzyme produces nitric oxide; a free radical that has several functions in the body, for example, in the blood vessels nitric oxide induces vasorelaxation, decreasing blood pressure. In the brain nitric oxide production modulates transmission of information between neurons without the need for a synapse between them. Normally nitric oxide is produced by other forms of Nitric Oxide Synthases located in brain cells (nNOS) and endothelial cells in blood vessels (eNOS); so why is the iNOS different? iNOS is only activated during inflammation or ischemia, it produces way more nitric oxide than the eNOS and nNOS. In principle this extra production of nitric oxide should be helpful to keep brain cells affected by stroke from dying, however, this excess nitric oxide can start activation of other biochemical pathways that induce cell death.

When a stroke patient arrives at the hospital at the emergency room, they try to restore blood flow to the brain (reperfusion), which will prevent the patient from dying; as the blood flow is restored, oxygen from the blood starts to permeate in the affected tissues which is a good thing, but the oxygen combines with the excess nitric oxide and forms Peroxynitrite, a very toxic free radical, that causes cell death which worsens the already critical damage originated by stroke.

What we try to do in our lab, is to find medicines that can inhibit the iNOS function, to decrease the excessive production of nitric oxide and in turn prevent the formation of peroxynitrite during reperfusion therefore decreasing the amount of damage in the brain.

What could result from this area of research?
Most stroke patients present serious neurological problems after recovery, due to damaged cells resulting from ischemia–reperfusion, if our approach is successful, it could reduce this damage, and minimize or eliminate some of these neurological problems, which in turn would give the patient a better quality of life.

This is a very brief summary of what I do. I am very happy to answer any questions that you might have.

Thank you for reading!

Is Homeopathy a real medical science?

As a pharmacologist, I often meet people who ask me about how "alternative remedies" work, especially Homeopathy. A few days ago a good friend just asked the same thing to me, and I felt compelled to write about it.

Homeopathy was first proposed in 1796 by German physician Samuel Hahnemann. In those years, the pathophysiology of illnesses was not well understood and neither were the mechanisms of action of the medicines available. Hahnemann formulated the idea he called "Law of Similars" which explained that substances that cause a symptom in healthy individuals could be used to treat patients who had those same symptoms. His idea for explaining this effect was that a preparation causing those same symptoms would empower a natural 'vital force' which would in turn eliminate the original disease.

Hahnemann thought that large doses of the drug would be bad, since they would worsen the original symptoms, so he thought that diluting the drug to very small doses would cure the disease. So he devised a centesimal dilution scale, and said that the more diluted a drug, the more effective it would be. In his dilutions he would use a tincture or extract from a plant, then dilute it by a factor of 100 at each stage so a 2C dilution would be one part in a hundred, then he would take one part and dilute it in a hundred to create a 3C dilution and so on. For most remedies he defined that 30C dilutions were the optimal concentration, this would be equivalent as 1 part of original tincture in 1E60 parts of solvent.

Now, let's think about this for a moment. According to chemistry and physics, it is impossible to keep diluting things indefinitely because eventually you'll get to the point where you have individual molecules or atoms, which cannot be diluted further. Avogadro's constant which is 6.023E23 mol-1 indicates the amount of atoms that exist in one mole of any given element or compound. This means that if you diluted a mole of any substance, you'd be reducing the available atoms of the solute in each dilution. If we follow the centesimal dilution scale used by Hahnemann we get that a 12C dilution is 1 part of solute in 1E24, this gives us reasons to understand that there is roughly about 60% probability to find 1 molecule of the original material in the dilution if one mole of the original material was used. If we think about a 30C dilution, it would most likely be only solvent, with no molecules of the original material remaining.

Knowing this, it is very likely that the beneficial effects reported by patients about homeopathy are due to Placebo effect. This has been observed in multiple clinical trials comparing Homeopathy and Conventional medicine against Placebos. In these trials homeopathy has not been significantly different than any placebo. There are few trials that have reported positive results, however these results have not been repeated by anyone. Meta-analyses performed on large groups of studies have also failed to show any positive results by Homeopathy. As for now, there is not any convincing scientific evidence to back any of the claims of homeopathy, therefore homeopathy is just pseudoscience.

Pharmacology is a real multidisciplinary scientific endeavor, which has experimental results that can be independently observed and tested by any other scientist. Its principles have been discovered over centuries of careful research and with the advancement of technology, it will most likely find treatments or cures for illnesses that cannot be treated at the present time.

So, what do you think?
Would you resort to treatments that lack any evidence?