Stem Cells + Lasers = Teeth!

A group of researchers from Harvard has recently accomplished to regrow rat teeth using a laser and stem cells. They used a low-power laser to coax stem cells into growing dentin. This could have major impacts on the future of dentistry and also offer new possibilities in wound healing and bone restoration.

Biologically active molecules, called growth factors, trigger stem cells to differentiate into specialized cells. If different growth factors are introduced, different cell types will form. In order to grow tissue from stem cells, scientists usually have to extract stem cells from the body, genetically modify them in a lab and reintroduce them to the body. The new laser-technique would be non-invasive and much faster and more efficient.
“Our treatment modality does not introduce anything new to the body, and lasers are routinely used in medicine and dentistry, so the barriers to clinical translation are low,” said David Mooney, leader of the research team.

The team set up a mini-dentist office and drilled holes into the molars of rats to simulate human tooth decay. Human stem cells were introduced to the pulp and a low-light laser was applied to stimulate the growth factors. Then, the teeth were sealed with temporary caps for three months. After three months, x-rays were taken and the scientists found that the dentin had regrown due to the laser and the stem cells.

Now the Harvard team want to take their work to human clinical trials. They are currently working with one of the National Institutes of Health in the USA to outline the necessary safety and efficacy parameters.

Sources:
http://www.seas.harvard.edu/news/2014/05/researchers-use-light-to-coax-stem-cells-to-repair-teeth
http://www.iflscience.com/health-and-medicine/scientists-use-lasers-regrow-teeth-stem-cells
http://stm.sciencemag.org/content/6/238/238ra69

How Instant Photography Works

Traditional slide films used in photography consist of a plastic base that is coated with a layer of light-sensitive silver compound. Color films use three layers: one is sensitive to red light, one to blue light, and one to green light. When the film is exposed to light, each layer forms metallic silver when met with light of the right color, e.g. the green-sensitive layer forms metallic silver when exposed to green light reflected from a green shirt. Therefore, a chemical record of light and color patterns is produced. In order to get a picture from from this, a series of chemical baths containing dye developers and dye couplers has to be applied.

The paper used in instant photography consists of the same layers as traditional slide films, but there are additional layers containing all the chemicals needed for the development of the picture. The base layer is black and on top of it sit the different color layers. Under each color layer there is a developer layer with dye coupler. On the very top sit the image layer, the timing layer, and the acid layer.

A critical part for the chemical process, during which the picture will be developed, is the reagent. It consists of opacifier, alkali, and other chemical substances and is located between the light-sensitive layers and the image layer. The reagent is kept in a blob at the very edge of the plastic sheet of the paper, so the light-sensitive layers will not start to develop before they have been exposed. After taking a picture with an instant camera, the paper will come out of the camera. In doing so, it passes rollers that spread the reagent over the plastic sheet which starts the development process. As the reagent chemicals move downwards, they create metallic silver from exposed particles in each layers. The reagent also dissolves the dye couplers which then start to move towards the image layer. Metallic silver stops the dye from travelling up, therefore only dye from underneath of unexposed layers can make it to the image layer to create the picture. Meanwhile, the opacifiers and alkali in the reagent react with the acid layer of the paper. As a result, the opacifiers become clear, which makes the image visible. The timing layer is used to slow down the opacifiers and alkali, so the opacifiers will not turn clear before the image is fully developed underneath.
As soon as the opacifiers are clear, you can view your photograph!

Cancer "Stem Cells" Confirmed

The existence of cancer "stem cells" has been reported before, but due to unreliable testing methods it has never been scientifically confirmed.

In a recent study, conducted by researchers from the University of Oxford and Swedish researchers, malignant bone marrow cells of participants who suffer from myelodysplastic syndrome (MDS) were extracted. MDS is a disease that often develops into leukemia.
The growth of the extracted cells was monitored by the researchers and using genetic tools they were able to identify a rare subset of the malignant cells that sat atop the cell hierarchy. These cells encouraged other cells to mutate and form cancer and in contrast to other mutated cells they were able sustain themselves. In short, without these cancer stem cells, the other cancer cells could not survive.

This discovery offers the prospect of new cancer therapies that target the cancer stem cells exclusively. Dr Petter Woll, the first author of the study, compared the process to tending a garden: "It's like having dandelions in your lawn. You can pull out as many as you want, but if you don't get the roots they'll come back."

However, the development of a therapy that specifically targets cancer stem cells will take a lot of time. Now that researchers have found a way to identify the stem cells, they can begin to study how they actually function. Only then the development of a drug or other form of therapy can start which will also have to go through clinical trials before it can be approved for general use. Dr Woll also cautions that the stem cells of other cancer types are likely to look and function differently from the MDS cancer cells and therefore require additional research.

Sources:
http://www.ox.ac.uk/news/2014-05-16-genetic-tracking-identifies-cancer-stem-cells-patients
http://www.iflscience.com/health-and-medicine/mutations-cancer-%E2%80%98stem-cells%E2%80%99-tracked-first-time
http://www.sciencedirect.com/science/article/pii/S1535610814001342

Cardiac Disease Model Based on Stem Cells

Barth syndrome is a rare and currently untreatable cardiac disease. It affects the heart and the sceletal muscles and because it is linked to a mutation of a gene in the X-chromosome patients suffering from it are mostly male (since females have two X-chromosomes, both of them would have to carry the mutation to cause the disease in women).

A team of American scientists took skin cells of two Barth syndrome patients and converted them into induced pluripotent stem cells that carried the mutation of the gene called TAZ. These stem cells were then placed on a chip carrying biochemical support where they grew to form diseased heart tissue.

In order to confirm that the disease causes weak heart contractions the scientists used genome editing to modify the TAZ of normal cells. The TAZ product was then delivered to the diseased tissue which corrected the defect in heart contraction.

Why is this important?
This is the first tissue-based model that shows how a rare heart disease can be corrected. The knowledge derived from this model can help to develop drugs that could cure inherited cardiac diseases.

Sources:
http://www.seas.harvard.edu/news/2014/05/heart-disease-on-chip-advances-tissue-engineering
http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.3545.html
http://www.iflscience.com/health-and-medicine/heart-disease-chip

Stem Cell-Based Cure for MS Found?

Multiple Sclerosis (MS) is a degenerative disease of the nervous system. It causes a loss of myelin, the insulating material that surrounds neurons and is essential for carrying electrical impulses to the brain. Over 2.3 million people worldwide suffer from MS. Currently, there is no cure nor a therapy that has proven to be effective in the long run.

In a recent study, scientists from Utah and California altered the central nervous system of mice, so they would develop a MS-like condition. Later, human neuron precursor cells that had been derived from human embryonic stem cells were injected into the spinal cords of the mice. After only two weeks, the mice had started quite drastic clinical recovery and were able to walk again, which the disease had prevented them from doing before. Furthermore, the mice recovered 73 % of their motor skills and this improvement could be sustained for six months. An examination of some of the mice's spinal cords showed that inflammation and demyelination caused by the MS-like condition had decreased significantly.

While the injected stem cells were actually rejected by the mice's bodies they still caused the desired effects. This led the scientists to the conclusion that the alleviation was likely triggered by certain chemical signals induced by the injected cells. Now the scientists are hoping to isolate these chemical signals and to put them in a drug in order to make administering the therapy easier.

Sources:
http://www.newswise.com/articles/mice-with-ms-like-condition-walk-again-after-stem-cell-treatment
http://www.iflscience.com/health-and-medicine/stem-cell-therapy-allows-mice-ms-condition-walk-again
http://www.cell.com/stem-cell-reports/abstract/S2213-6711(14)00112-X?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS221367111400112X%3Fshowall%3Dtrue?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS221367111400112X%3Fshowall%3Dtrue

How to Travel Back in Time and Shoot Hitler

This is an easily understandable manual that will explain to you how to travel back in time and kill Hitler. By doing this, you will (perhaps) be able to prevent the Holocaust and WWII!

What you will need:

• time machine
• gun

How long it will take you:

• depends entirely on you

Instructions:

1. Acquire a functioning time machine

2. Acquire a gun of your preference (we recommend semi-automatic or automatic)

3. Choose an appropriate killing-time (e.g. during a speech → not appropriate)

4. Choose an appropriate location where the assassination will take place (or took place??)

5. Set your time machine to the desired time and location

6. Travel through time and space (don’t forget to bring your gun!)

7. Find Hitler

8. If he is alone, shoot him.

9. If he is not alone, assess the situation and decide if the other people present pose a threat to you or you mission.

10. If they do, shoot them too. We recommend you be quick about it while they are still surprised.

11. If they do not pose a threat, proceed to shoot Hitler and let the others live.

12. Travel back home and reward yourself with a drink.

Congratulation, you have just saved millions of lives and prevented a bloody war!

Camera Lucida Instructions

Our group agreed that the instruction is helpful, yet there were several things that would need improvement to turn this into a good instruction sheet. First of all, there should be a short explanation on what a camera lucida actually is and what it can be used for. At the top, a list of all the materials needed to build the camera would be useful, otherwise people who start reading the text before having a close look at the pictures might encounter problems. Moreover, the units of length are illegible, therefore it is hard to find out if the author meant centimeters, millimeters, or a completely different unit. Another thing our group would change is the structure of the two paragraphs as we would rather use bullet points to describe the building process. While we think that the pictures are very helpful and that the author obviously put a lot of effort into these instructions, we are convinced that the individual steps could be structured better.

Sperm From Stem Cells?

Infertility is a problem that affects many couples and that may lead to psychological impacts. Men afflicted by certain inherited genetic anomalies produce only very few sperm cell or no sperm cells at all.

Scientists in the US have just made a huge step towards helping these men: they have created sperm precursor cells from human skin cells.
Induced pluripotent stem cells were produced from the skin cells of three men who cannot produce any sperm due to a genetic mutation, and from two healthy men. These stem cells were injected into the testes of mice, where they transformed into sperm-precursor cells. However, they did not develop into mature sperm cells, probably because the genetic difference between humans and mice is too big.
While the stem cells from the healthy men performed better, the fact that the infertile men's stem cells could produce any sperm cells at all was a huge breakthrough.

Now scientists hope to replicate this study with animals that are more closely related to humans, in order to achieve better results. There is just one big problem: the stem cells caused tumors in the mice. This issue will probably have to be solved before more trials can be conducted.

Nevertheless, this new study provides a model that can help scientists to understand the earliest steps of human reproduction and the biological problems infertile men have to deal with. It also gives hope to men who became infertile due to cancer treatments.

Sources:
http://www.cell.com/cell-reports/abstract/S2211-1247(14)00264-2
http://www.iflscience.com/health-and-medicine/scientists-generate-sperm-precursors-skin-cells-infertile-men
http://med.stanford.edu/ism/2014/may/germ-cell.html
http://www.montana.edu/news/12625/reijo-pera-and-team-stem-cell-research-holds-promise-for-male-infertility
http://www.livescience.com/45278-stem-cells-sperm-production.html

Blood From Stem Cells

Every year, more than 100 million blood transfusions are needed worldwide. The best blood type for transfusions is type 0 negative, due to its universal acceptance. However, only 7 % of the world's population has this specific blood type and is therefore able to donate it.

Now, for the first time in history, a research team from the UK has managed to produce artificial 0 negative blood from induced pluripotent stem cells in the appropriate quality required for transfusions. They are highly optimistic that human trials will start within the next three year. If these trials prove the artificial blood to be successful, the dependence on blood donors could be reduced drastically. The second important advantage of artificial blood is that is is disease free - guaranteed!

However great the advantages of artificial blood from stem cells may be, there is still one challenge to overcome: as of yet, there is no quick and economically feasible way to produce the quantities needed. One single transfusion unit consists of more than a trillion blood cells; and now multiply this number by the number of transfusions needed yearly. Furthermore, clinical trials involving humans usually take years, so we could still be a decade away from the everyday use of artificial blood transfusions.

Sources:
http://www.iflscience.com/health-and-medicine/factory-made-blood-nearing-human-trials
http://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/7482/Artificial-Blood-on-Its-Way-to-Clinical-Trials.aspx
http://www.ft.com/cms/s/0/f6f1914c-c3d6-11e3-870b-00144feabdc0.html#axzz2znoegDuM

The Napalm Girl

The photograph shows a flat scenery where only grass and small shrubs and bushes grow. Right through this flat wasteland runs a broad street and a small house can be seen in the background. The background is filled by an enormous wall of smoke, like the ones caused by huge explosions. In the foreground you can see 5 children, of which three seem to be crying, one completely naked, one dressed in a shirt and underpants, one dressed in what seems to be pyjamas, one dressed in a shirt and what seems to be either long, airy pants or a skirt and one smaller child apparently in just a shirt. Behind them, there are five American soldiers in full Vietnam war gear, seemingly completely unfazed by the suffering children as they do not seem to have any intention of intervening or helping them. The soldiers also do not expect any attacks as three of them carry their weapons at least partly concealed.

Narrative Article Homework: Crimea

We visit Irina and Pavel on a bleak day in early March. Their apartment, located on the sixth floor of a soviet-style building on the outskirts of Kiev, consists of only three rooms. In the center of the living room stands a small coffee table on which a framed picture of a young man is surrounded by candles and flowers. The young man on the photo is their son Ivan, 20. He is currently serving in the Ukrainian military and is currently deployed in Sewastopol on the Crimea. With Russia invading the peninsula, his parents fear that he might never come back. “If our government decides to fight the Russians, my son and his comrades will die for sure”, Irina says as she is wiping tears from her cheeks.

Currently, thousands of Ukrainians are losing sleep over the fate of their loved ones, just like Irina and Pavel. The conflict with Russia has been escalating since Russia took first steps towards an annexation of the Crimean peninsula.

Rhetoric Analysis of an Opinion Article on Stem Cells

http://www.aish.com/ci/sam/48969936.html

The article discusses the ethical issues of stem cell derivation from the view of the Jewish religion. The author explains ethical questions in a neutral style and provides answers to them based on the Torah and Jewish religious teachings. While doing so, he uses many examples, like the example of a man dying of liver failure. The author states that derivation of stem cells from aborted fetuses is considered unethical in Jewish religion, with the exception of fetuses aborted because they were a hazard for the mother's life. In contrast to Christianity, Judaism does not consider the derivation of stem cells from pre-embryos (leftover embryos from IV-fertilizations) as unethical. Nevertheless, it opposes the creation of pre-embryos for the purpose of their destruction, since this practice would devalue human life.

My CAJ: Stem Cells

My Current Affairs Journal is about stem cells. I will mainly focus on adult pluripotent stem cells and the ethics of embryonic stem cell use.

What are stem cells?
Stem cells are unspecialized human cells that have the ability to transform into any specialized cell, e.g. a blood cell or a muscle cell. Scientists hope to use stem cells to treat diseases like Alzheimer's disease, repair damaged organs, or even grow organs from them.
Until recently, the most common way to derive stem cells was from human embryos. To gain stem cells, scientists use embryos that were created for in vitro fertilization but not implanted in the womb. Since the embryos are destroyed in the process, the use of embryonic stem cells sparked many ethical debates. While stem cells can also be derived from adults, this process is much more challenging, because adult stem cells are rare and cannot be cultivated as easily as embryonic cells.
However, in 2006 scientists discovered a way to "reprogram" specialized adult cells so they would assume a stem cell-like state. These cells are called "induced pluripotent stem cells" or adult pluripotent stem cells (pluripotent = ability to differentiate into almost any cell type).

Sources:
http://stemcells.nih.gov/info/basics/pages/basics1.aspx
http://learn.genetics.utah.edu/content/stemcells/scissues/
http://www.medicalnewstoday.com/info/stem_cell/

PSA: After-Death Avatars

Being in a very loving relationship with a very big age difference, I can fully understand the temptations of the idea of creating after-death avatars of your loved ones. But don’t make a fool of yourself. Death is an irreversible part of life and no computer program can change that. Don’t lose your life to an illusion. Better learn to let go and to heal.

A Day in My Life

Yesterday was a typical, nice day of my life. I had to get up early, at seven o’clock, because Tuesday’s Russian class starts at 8:15. I usually don’t like having to get up that early, but at least I got to enjoy a beautiful sunrise from my balcony. After my usual breakfast – cornflakes with milk and a glass of fruit juice – and my usual morning hygiene I went on my way to the university. I sat through a Russian and an English lesson, and then it was time for my lunch break. After grabbing a sandwich and a fruit smoothie from a nearby shop, I returned to do some of my Russian homework together with a group of fellow students. I had hardly completed half of my tasks when the next Russian lesson started, followed by a somewhat tiring Spanish lesson. When the clock finally showed 16:45 I was starving. I went to my good friend Simon’s place where we made lasagna. To be perfectly honest, he made it while I grated the cheese, but it turned out deliciously. In fact, we made so much I’ll be eating it for the next two days. When we had finished our meal we did some more of our Russian homework and then I went on my way home. In the tram I met an old flat mate of mine who had spent half a year in Peru and had just returned to Graz. We had a quick catch-up chat before we had to separate at Jakominiplatz, as we were going in different directions, but promised to keep in touch. At home, I stacked two to three servings of lasagna into the fridge and called my love. After my conversation with him (mainly about our weekend-plans), I tried to finish the book I’m currently reading, but a few chapters before the end I dozed off.