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Saying Goodnight to Bed Bug Bites

Cimex lectularius

Cimex lectularius, the most common bed bug           Source: Gilles San Martin on Flickr

Many of you may not think that bed bugs pose a significant threat in your life. Several believe that only cheap motels and hostels became infested with these parasites, and that I was never at risk of coming into contact with them. It turns out this issue may be closer to home than we think. According to the British Columbia Ministry of Health, there have been increased reports of infestation, particularly in Downtown Eastside Vancouver, but also throughout British Columbia. Houses, apartment buildings, hotels and university and elderly residences across Canada have fallen victim to infestation.

Scientists at Simon Fraser University have recently come up with a concoction of pheromones that attract and trap bed bugs. After years of investigating this issue, they found the right balance of pheromones that causes bed bugs to be drawn to the source of the chemical attractant. The key is histamine, which bed bugs interpret as “safe shelter”. As soon as they come into contact with the histamine, they stay there, despite whether or not they have recently fed. This essentially helps stop their reproduction and spread. This mixture of pheromones has already proven extremely effective, and has even been tested in bed bug infested areas in Metro Vancouver.

Here is a video by Simon Fraser University introducing the scientists responsible for this research:YouTube Preview Image

 

Bed bugs were basically eradicated in the mid-20th century due to widespread use of pesticides such as DDT. However, in recent decades they have been making a global comeback, likely due to increased international travel and pesticide resistance. Reaching epidemic proportions, bed bugs are returning in higher abundances, distribution and intensity of infestation. For this reason, it has become imperative to find more effective methods of early detection and extermination of bed bugs.

Bed bug bite

An example of a bed bug bite                                   Source: hiroo yamagata on Flickr

Bed bugs have not been proven to carry infectious diseases, but their bites can be itchy, cause rashes, and some people can suffer severe allergic reactions. Moreover, their presence can be irritating and distressful, causing loss of sleep, anxiety and paranoia. Many people go to great lengths to minimize the effects, including the use of pesticides and radical cleaning.  Pheromones are a much less harmful way to get rid of the parasite. Finding the right combination of histamine and other chemicals could have huge implications for the global eradication of bed bugs. Low-income areas are usually unable to afford professional extermination, and since the cost of the pheromone method is low, these regions will have better opportunity for monitoring and preventing infestation.

So, if you ever have the misfortune of getting bed bugs in your home, hopefully it happens after next year, when the pheromone treatments should be widely available.

– Anne Persson

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Life in a Petri Dish: From Skin Cells to Fertility

The number of partners facing infertility in Canada has doubled since the 1980s; it is now predicted that every one in six couples face infertility. With the numbers rising, due to factors such as obesity and substance use, this issue is becoming increasingly more common in our modern world and scientists across the globe are in a constant race to overcome it.

New research emerging from Cambridge University has provided hope in the form of a new infertility treatment. In collaboration with the Weizmann Institute of Israel, researchers have come forward with a potential new form of in-vitro fertilization. Its origin? Human adult skin cells.

IVF: the insertion of sperm into a human oocyte (egg cell).

IVF: The insertion of sperm with a glass pipette into a human oocyte (egg cell). In-vitro Source: Wikimedia Commons

For the first time, scientists have been able create manmade (reproductive) primordial germ cells, known as PGCs; these cells act as predecessors and are considered the common origin of  both sperm and egg cells. PGCs arise from pre-existing adult stem cells, which is an undifferentiated cell that has the ability to develop into many different tissue types. Their ancestor-like quality that creates a common origin, allows the eventual creation of  many different cell types, such as skin and liver cells.

Kyoto University used skin cells to create mice pups in 2012.  Lab Mouse Source: Google

Kyoto University used skin cells to create mice pups in 2012.
Lab Mouse Source: Wikimedia Commons

The team of researchers, led by Hanna and Azim Surani, followed a “recipe” originating from a Stem Cell Lab at Kyoto University, who created mice pups from a female germ cell by re-programming stem cells back in 2012. Based on this, the Cambridge-Weizmann team replicated the in-vitro portion of the experiment, where they grew the cells in a sterile and controlled environment.

The team was successful in making the primordial reproductive cells from human stem cells. The key finding was a gene known as SOX17, who is responsible for directing stem cells into their specialization; this is how primordial germ cells are created. This gene can also direct stem cells into becoming the external layer of skin, therefore showing that the reprogramming of an adult tissue type, such as skin cells, could give rise to the primordial germ cells.

Current British law has banned any fertility clinics in the United Kingdom from using a manmade sperm and eggs to treat an infertile couple, due to both ethical reasons as well as safety concerns. If this law is changed, the creation of a genetically identical sperm or egg cell can be taken from a patient for use in in-vitro fertilization.

Mother and Child Source: Wikimedia Commons

Mother and Child
Mother Source: Wikimedia Commons

This discovery has laid down foundation for all future research; scientists can now compare the development of both sperm and egg cells in both healthy as well as infertile people. Representing a huge step forward in the world of stem cell biology, the researcher’s work, published in the journal Cell, may mean a change in the age at which a woman can stop having children. This breakthrough means that manmade primordial germ cells are capable of passing on an offspring’s genetic code to their own offspring, creating the fundamental bond from generation to generation.

Check out Cambridge University’s video on a similar topic, the derivation of brain cells from skin cells:

Thanks for reading!

Samantha Mee