Category Archives: chemistry publishing

Shortcuts to Weight Loss: The Risk-Benefit Analysis of Weight Loss Supplements

With the busy lives that humans now occupy within society, like post-secondary students during exam season for example, balanced and nutritional dietary and exercise are often disregarded or not of a major priority. As a result, the body begins to accumulate fats to act as a storage for excess energy from the foods we eat and thus leads to a case in what society would call “overweight”. The extreme case would result in obesity and this has been a growing concern (and a rather sensitive topic to some) over the past years because excessive body weight is associated with various cardiovascular diseases, diabetes, asthma, and overall, a reduction in life expectancy. However, there is one suggestion that is portrayed by media and human society that is supposedly a shortcut to this problem: weight loss supplements.

Weight loss supplements contain common active ingredients such as bitter orange (synephrine), chromium, guar gum, and Hoodia(1). Synephrine, the main composition of bitter orange, works to suppress appetite and increase the rate of metabolism, thus increasing the number of calories burned (1). Chromium is a mineral that helps to regulate insulin and helps promote muscle growth and fat reduction and guar gum helps block absorption of fats in the body and increase the feeling of fullness whereas Hoodia temporarily suppresses your appetite (1).

Although these active ingredients and their functionality seem to be the solution to obesity, there are many side effects. First of all, synephrine is very similar to ephedrine (see Figure 1), a banned stimulating drug by the Food and Drug Administration due to implications with stroke, heart attacks, and hypertensions, in chemical structure and have many similar characteristics (2).

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Figure 1: Chemical structure of synephrine compared to ephedrine

Secondly, although chromium exists naturally in our bodies and certain foods, the intake of excessive chromium is disadvantageous because chromium, like other heavy metals, is rather toxic to the human body even at low concentrations. Moreover, although guar gum and Hoodia (Figure 2) work in synch to suppress the production of fats for excessive energy storage as a result from eating food, the overall results are still not proven and can potentially lead to malnutrition (1).

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Figure 2: Chemical structure of guar gum (top) and Hoodia (bottom)

To note, a research by Eichner, Maguire, Shea, and Fete have determined that many weight loss supplements are still on the market today that contain other ingredients that are banned due to psychiatric issues and complications with the cardiovascular and nervous system (3). Other ingredients that are not banned but are subject to caution and consumer knowledge are also present in many weight loss supplements(3).

In conclusion, although shortcuts are available to everyday medical conditions such as obesity, there are also many drawbacks to such methods. The optimum method would be the natural method of weight loss which involves a balanced nutritional dietary and exercise, despite how busy our lives may be or what telemarketers or advertisements tell you.

-Andrew Siu

References

Eichner, S., Maguire, M., Shea, L.A., and Fete, M. Journal of the American Pharmacists Association 2016, 5, 538.

Fitday. How do weight loss pills work in the body?  http://www.fitday.com/fitness-articles/fitness/weight-loss/how-do-weight-loss-pills-work-in-the-body.html (accessed Oct. 31, 2016).

Google Patents. Pharmaceutical compositions having appetite suppressant activity. http://www.google.com/patents/US7166611 (accessed Oct. 31, 2016)

Nutrient Journal. Is bitter orange fruit (citrus aurantum as synephrine) new ephedra? http://nutrientjournal.com/is-bitter-orange-fruit-citrus-aurantum-as-synephrine-new-ephedra/ (accessed Oct.31, 2016).

Sci-Toys. Guar gum. http://sci-toys.com/ingredients/guar_gum.html (accessed Oct. 31, 2016).

A new environmentally friendly and healthy method to soften water

Aluminum was reported to be capable for removing mineral in water without involving sodium, according to online Environmental Science & Technology on Oct 4. This new method was motivated because of the negative effect resulted by current sodium-related water soften method, says by study coauthor Arup SenGupta.

As an environmental engineer at Lehigh University in Bethlehem Pa,  Sengupta believes that improving the traditional way of softening water can bring benefits to environment.

Hard water, which is defined as water contains significant amount of mineral ion such like calcium and magnesium , is relevantly difficult to lather by soap and usually form incrustation in containers or tubes.

Introduction to hard and soft water: YouTube Preview Image

The current method for solving problem of hard water is filtering through a tank with glass beads. The sodium ions covering on beads can exchange with mineral ions ,and this leads to soft water.

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However, this method has many negative effects. On one hand, the sodium added has negative effect on people’s health, for example, they can raise blood pressure. On the other hand, the system can not solve the problem once and for all, since it needs to be recharged by sodium-based brine regularly.

From the point view of chemistry, SenGupta and his colleagues select aluminum as a substitute of sodium. Actually aluminum ion has three positive charges and that means it is relatively unlikely for aluminum ion to exchange with mineral ions. So why they choose aluminum ion? The reason is that the aluminum can precipitate and gather on beads after exchanging instead of being taken away like sodium. This makes aluminum ions reusable.

The new system of aluminum was tested by researchers’ lab and was found to have better performances than old systems. It’s worth mentioning that the set up used was similar and that can make the possible renewing project in the future easier and cheaper.

So far, this new technique will still be challenged in practical use. “I see these great things all the time, but a lot of them just don’t make it financially,”  said by Steven Duranceau, an environmental engineer at the University of Central Florida in Orlando. On contrary, SenGupta keeps his enthusiasm, as he says “This is not a magic bullet; there are shortcomings, but none of these problems are impossible to overcome.”

 

Reference

J. Li et al. Aluminum-cycle ion exchange process for hardness removal: a new approach for sustainable softening. Environmental Science & Technology. Published online October 4, 2016. doi: 10.1021/acs.est.6b03021.

Happy Halloween: Beware of the caries!

Halloween has approached us. Among the daunting horror films and scary costumes come the dreaded likelihood of cavities AKA dental caries (DUN DUN DUN)!

As a child I always wondered how cavities form, but I never looked into it because I didn’t want to face the awful truth that my beloved candy is actually plotting against me. But now that I am older, and hopefully wiser, I have figured out the true story of the candy cavity curse!

It begins the moment you present that delicious piece of candy to your mouth, and the simple sugars, specifically sucrose, are released into your oral cavity. The sugar feeds the already present bacteria on your teeth [1], which live in the plaque growing on the enamel. Plaque forms normally on your teeth by the combination of sucrose, and proteins from your saliva [2]. However unpreventable, it can be removed by frequent tooth-brushing. So bacteria such as Streptococcus mutans (S. mutans), which are round, cariogenic (causes tooth decay), and anaerobic, feed on the sucrose provided by the candy, to form lactic acid through glycolysis [2].

Glycolysis is an important process in which energy is produced. The process is outlined generally below.

Hydrolysis of Sucrose to form Glucose and Fructose Image Credit: Charles E Ophardt http://chemistry.elmhurst.edu/vchembook/548toothdecay.html

Hydrolysis of Sucrose to form Glucose and Fructose Image Credit: Charles E Ophardt http://chemistry.elmhurst.edu/vchembook/548toothdecay.html

Formation of Lactic Acid from Fructose via Glycolysis. Image Credit: Charles E Ophardt http://chemistry.elmhurst.edu/vchembook/548toothdecay.html

Formation of Lactic Acid from Fructose via Glycolysis. Image Credit: Charles E Ophardt http://chemistry.elmhurst.edu/vchembook/548toothdecay.html

S. mutans lives in the plaque trapped between your teeth, and lacks oxygen. Therefore it uses glycolysis to produce lactic acid under anaerobic conditions [3]. Lactic acid is very acidic. It has a pH level of 2 [4]. The added acidity decreases the pH of your mouth to initiate the dissolution of the calcium phosphate in your tooth enamel [3]. Thus, the start of a cavity. A description of the process is explained in the video below.

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Despite the terror inflicted on my teeth due to my obsession with candy, I refuse to deprive myself of the traditional Halloween treat. Although ceasing the intake of sugar would obviously decrease the production of lactic acid on my teeth, also decreasing cavity formation, there are other methods being investigated to protect our teeth.

For example, Shelby Kashket, and Dominick P. DePaola have studied the anticariogenic effects of cheese [5]! They researched that possibly due to the buffering effects of dairy proteins on the lactic acid formation, and increased salivation when eating cheese, this helps in battling the cariogenic effects of S. mutans!

Additionally, Chu-hong Hu et al. developed a way to make large quantities of Glycyrrhizol A, an extraction of licorice root, into a sugar-free lollipop which can kill the S. mutans bacteria [6]! Talk about fighting fire with fire, or in this case, fighting candy with candy!

Finally, you can also use toothpaste with sodium bicarbonate, which raises the pH level in your mouth and neutralizes the acid [1]. Or rinse with fluoride, which speeds up the remineralization of the enamel, too [7].

So, I guess what I’m saying is, long live candy! And, apparently, cheese!
…Just make sure you brush and floss often, as well.

Happy Halloween, everyone!

Nicole Yipp

References:

[1] Dr Chemical, http://drchemical.com.au/why-does-sugar-cause-tooth-decay (accessed Oct 31, 2016).

[2]Loesche WJ. Role of Streptococcus mutans in human dental decay. Microbiol Rev. 1986;50:353–380.

[3] Ophardt, C. E. Tooth Decay http://chemistry.elmhurst.edu/vchembook/548toothdecay.html (accessed Oct 31, 2016).

[4] Lactic acid; MSDS No. 9924447 [Online]; Science Lab; Houston, Texas, May 21, 2013, http://www.sciencelab.com/msds.php?msdsId=9924447 (accessed Oct 31, 2016).

[5] Kashket, S.; Depaola, D. P. Nutrition Reviews 200260 (4), 97–103.

[6] Hu, C. H.; He, J.; Eckert, R.; Wu, X. Y.; Li, L. N.; Tian, Y.; Lux, R.; Shuffer, J. A.; Gelman, F.; Mentes, J.; Spackman, S.; Bauer, J.; Anderson, M. H.; Shi, W. Y. International Journal of Oral Science 20113 (1), 13–20.

[7] Fluoride And Your Teeth http://www.colgate.com/en/us/oc/oral-health/basics/fluoride/article/fluoride-and-your-teeth (accessed Oct 31, 2016).

Bacteria can help us to extract drinking water and mining minerals from the ocean?!

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Figure 1: The global water crisis. Author: MrGauravBhosle from Wikimedia. Source: https://commons.wikimedia.org/wiki/File:Water-crisis.jpg

Nowadays, people around the globe are facing a huge problem with the clean water crisis. More than 36 countries in the world cannot provide drinkable water resources to their citizens. However, the good news is scientists have already found a technique to extract drinkable water from seawater, which saves many people around the world.

The basic idea of this technique is called “seawater reverse osmosis.” By using energy to force the seawater pass through a special membrane which can only allow water molecules to go through, the clean drinking water can be extracted from the general seawater. Furthermore, the remaining salt and other types of heavy metals or minerals will be left on the other side of the membrane. However, the biggest problem is that in the remaining salts and metals solution, which also called “Brine” solution, is highly toxic, and can also cause serious damaging to the local environment. Figuring out how to deal with this problem had been the biggest challenge for Chemists and Ecologists for decades.

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Figure 2: The seawater reverse osmosis system. Description:” A – Applied pressure B – Seawater in C – Contaminants D – Semi-permeable membrane E – Potable water out F – Distribution.” Author: Colby Fisher from Wikimedia. Source :https://commons.wikimedia.org/wiki/File:Simple_RO_schematic.png

Recently, the problem had been solved by the finding of one special type of Bactria. Such bacteria will create electrical charges during metabolism. If we can mix the bacteria with the Brine solution, the electrical charges can combine with the metals which usually carry positive charges in the aqueous environment. After accumulating and precipitation, the metals can be extracted from the brine solution, and the remaining materials are safe again to be released back to the ocean without damaging the environments.

However, the remaining metals which had been accumulated and precipitated by the bacteria can be used in so many ways. In the seawater, more than 40 types of minerals and metals are present, and most of them are very precious for many industries and medical companies. Also, in a lot of countries that have less natural resources, such as Japan, Korea, Singapore, UK…etc. Mining metals can cost a serious amount of money. For example, Mining Magnesium in Singapore can cost 4.5 billion dollars a year, which is a huge part of the outcome.

By using bacteria to accumulate metals from seawater, much less money can be spent, and the percentage yield of this technique is also very high. Pure products can be achieved without risking miners’ life, which is also a big improvement in our modern society.

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In the future, more and more biomining techniques will be applied to our daily life, and the win-win situation can also be achieved. Not only can we solve the global water crisis problem, but also can help many countries to use a cheaper price to have more mining resources.

Reference:

  1. Components of Seawater: http://www.seafriends.org.nz/oceano/seawater.htm
  2. Biomining costs: http://web.mit.edu/12.000/www/m2015/2015/bioleaching.html
  3. TED Talks — Damian Palin: https://www.ted.com/talks/damian_palin_mining_minerals_from_seawater/transcript

Is antibacterial soap really effective or just risky?

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Figure 1: Common Antibacterial soap sold at grocery stores. Author: Joe Raedle from Getty Images. Source: http://www.pbs.org/newshour/rundown/antibacterial-soap-may-harm-good-fda-says/

If consumers are given the choice of plain soap or antibacterial soap, the majority of the consumers would prefer to purchase antibacterial soap. It is because antibacterial soap is known to control the spread of germs. However, antibacterial soaps will soon no longer be found in grocery stores in the United States. The U.S Food and Drug association (FDA) has officially banned 19 soap ingredients that are known to be the “germ killers” (1). However, Jane Woodcock, the director of FDA’s Centre for Drug Evaluation and Research, claims there is no supportive evidence that antibacterial soap is more effective in killing germs than plain soap and water (1).

Blaise Boles, a microbiologist from the University of Michigan, conducted a study showing triclosan(2), an ingredient commonly found in antibacterial soaps, increases the risk of people getting staph infection (4). Staph infection is caused by staphylococcus bacteria that can be found in the nose or on the skin of an individual (4) Boles and his colleagues swabbed 90 people’s noses to collect samples. The results showed 37 people had triclosan present in their nasal secretions, and 64% of these people were infected with staph(3). The researchers were surprised by the findings of the study because triclosan is previously acknowledged to reduce bacteria contamination. FDA expresses their concerns over the health risks associated with long-term use of antibacterial soaps. The chance of one getting pneumonia increases when they are infected with staph.

There are not many studies showing triclosan-resistant bacteria poses any major health risks to consumers. However, FDA decides to ban retail stores from selling antibacterial soaps to the general public in U.S unless the manufacturers can provide supportive evidence that antibacterial soap is capable of killing bacteria. The U.S Centers for Disease Control and Prevention (CDC) instructs citizens to scrub their hands with plain soap for at least 20 seconds before washing under running water (5). An alternative way to reduce the spread of germs and avoid getting sick is using hand sanitizer with at least 60% alcohol (5).

The take home message is that antibacterial soap does not necessary halt the spread of germs more effectively than regular soap. As long as the general public uses the regular soap to wash their hands as instructed by CDC, the regular soap can also reduce the spread of germs. Therefore, the consumers do not have to spend a dollar or more on purchasing the antibacterial soap.

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The following video shows the proper way of washing hands:

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References:

  1. Science News for Students. Science & Society, Microbes: U.S. to outlaw antibacterial soaps. https://www.sciencenewsforstudents.org/article/us-outlaw-antibacterial-soaps (accessed on Oct 22nd, 2016).
  2. David Suzuki Foundation. Triclosan. http://davidsuzuki.org/issues/health/science/toxics/chemicals-in-your-cosmetics—triclosan/ (accessed on Oct 23rd, 2016).
  3. MOLE, B. (2014). Body & brain: Triclosan aids nasal invasions by staph: Antimicrobial compound may help bacteria stick around. Science News185(10), 12. doi:10.1002/scin.5591851011
  4. Mayo Foundation for Medical Education and Research. Disease and Conditions: Staph infections. http://www.mayoclinic.org/diseases-conditions/staph-infections/basics/definition/con-20031418 (accessed on Oct 24th, 2016).
  5. Centres for Disease Control and Prevention. Hand washing: Clean Hands Save Lives. http://www.cdc.gov/handwashing/when-how-handwashing.html (accessed on Oct 22nd, 2016).

Photo source:

  1. Copyright information: http://www.pbs.org/newshour/rundown/antibacterial-soap-may-harm-good-fda-says/

Vantablack, the darkest material ever made

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(Image Credits: SURREY NANOSYSTEMS https://www.surreynanosystems.com/vantablack)

The picture above shows Vantablack, which is the darkest artificial material ever made. The coating, which absorbs almost all light, was created by British company Surrey NanoSystems to eliminate light that interfere satellites and telescopes. Let us see what is this mysterious material and how it can be used.

1.Does the darkest means the blackest?

As we known, the color is actually a result of reflected light from the object. The color shown is depend on the light frequency. The Vantablack does not actually shows any colour since there is no light reflected from it. The reason why the light can not escape is because of the structure of Vantablack. It is made of a “forest” of tiny, hollow carbon tubes, each has the width of a single atom. According to the Surrey NanoSystems website, “a surface area of 1 centimeter squared would contain around 1000 million nanotubes.” These tubes can absorb light hits, so Vantablack is called the absence of color.

 

2.Does it feels like the way it looks?

“One of the things that people often say is ‘Can I touch it?’” said by Steve Northam from Surrey NanoSystems. “They expect it to feel like a warm velvet.” However Vantablack does not feels like the way it looks. When you touch Vantablack, it just feels like a smooth surface. Because the nanotubes are minute and thin, they will collapse easily by a slight human touch. So, Vantablack is extremely sensitive  to touch, that explains why it can not yet be applied to unprotected surfaces like cars —one brush of a hand can make material lose its magic.

3.How much does it weight?

One thing interesting is that, though Vantablack is vulnerable to damage, it is super robust against other forces, like shock and vibration. This is due to the fact that every carbon nanotube is independent, and has almost no mass at all. Plus, most of the material is air. “If there’s no mass, there’s no force during acceleration,” Northam says. This makes Vantablack ideal for protected objects that might have to endure a jouncy ride, like a space rocket.

4.Any possibilities beyond its original applications?

As mentioned above, the material was initially designed for fields of frontier science, like space launch, where its ability to limit stray light makes it ideal for the inside of telescopes. But it could be applied in more daily objects with right conditions. Northam says Surrey NanoSystems has already been approached by a handful of luxury watchmakers interested in incorporating Vantablack into their wrist candy, and high-end car manufacturers want to use it in their dashboard displays for stunning visual appearance.

To my opinion, the invention of Vantablank is a great achievement for material chemistry. It suggest that the appropriate design can make the simple element show characteristics we never expected. The Vantablank give approaches to development of  carbon-related synthesis.

Video:

Reference:

Evangelos Theocharous, Christopher J. Chunnilall, Ryan Mole, David Gibbs, Nigel Fox, Naigui Shang, Guy Howlett, Ben Jensen, Rosie Taylor, Juan R. Reveles, Oliver B. Harris, and Naseer Ahmed, “The partial space qualification of a vertically aligned carbon nanotube coating on aluminium substrates for EO applications,” Opt. Express 22, 7290-7307 (2014)

 

If Organic Molecules Were Human: NanoPutians

Although killer clown sightings are the main topic of discussion these past few weeks, there is one thing aspect in chemistry that is just as weird and creepy (because it is Halloween month): NanoPutians. NanoPutians were first introduced to me in my Chem 218 class and are defined as synthetic organic molecules that resemble human forms which include but are not limited to: athletes, monarchs, bakers, and chefs.

The process begins with the synthesis of a NanoKid which provides the structural backbone for the various forms of NanoPutians. This is carried out in two multistep reactions with the upper portion which includes the head and body and the lower portion which includes the waist and legs synthesized separately as shown (1):

nanoputian-upper-body

nanoputian-lower-body

The upper and the lower portions are then joined via a Pd/Cu catalyzed coupling reaction to yield the NanoKid as shown (1):

nanokid

Microwave radiation, in the presence of a 1,2 or a 1,3 diol, is the methodology for the “head-conversion reaction” of a NanoKid to yield the series of NanoPutians (1). Depending on the reaction conditions, the NanoPutian could resemble that of an athlete (NanoAthlete), a pilgrim (NanoPilgrim), a Green Beret (NanoGreenBeret), a jester (NanoJester), a monarch (NanoMonarch), a Texan (NanoTexan), a scholar (NanoScholar), a baker (NanoBaker), or a chef (NanoChef) as shown (1):

nanokid-conversion-reaction

Furthermore, if you are not satisfied with the diversity, miscellaneous reactions that do not implement a NanoKid backbone can yield NanoToddlers and NanoBalletDancers. A NanoPutian Chain can also be synthesized, with modifications to the synthesis of the upper portion of the NanoPutian to yield an AB polymer configuration, to resemble individual NanoPutians “holding hands” and to symbolize multinanolism and peace on NanoEarth (okay I’ll admit I made that up) as shown (1):

nanoputian-chain

Now you may ask yourself: “Who funds this kind of research?”, “Why would anyone invest their time on this?”, or “What is the significance in learning about NanoPutians to the scientific community?”. Truth be told, there is no known significance (yet), in terms of chemical and practical applications, which may explain the limited research in this area (2). However, the synthesis of NanoPutians contributes a significant role in aspiring the younger generations in science and more specifically, the field of chemistry (2). And sometimes, we tend to forget how important that really is. If scientific advancements are to be made in the future (and one can only predict what the future will look like), the younger generations must be inspired by science and motivated to learn more in order to solve the problems and answer the questions, that we could not, about the world we live in.

-Andrew Siu

Chem 300 Section 109

References

Chanteau, S., Tour, J. Synthesis of Anthropomorphic Molecules: The NanoPutians. Journal of Organic Chemistry 2003, 68, 8750.

NanoPutians. Wikipedia. https://en.wikipedia.org/wiki/NanoPutian (accessed Oct. 8, 2016).

 

 

 

 

 

 

Using medicine to reduce the risk of addictive gambling ?

Addictive gambling can have severely negative effects on a person’s lives. Because of such addiction, many people suffer from unemployment, financial debts and even families separation. Long time ago, a lot of scientists were really confused about why and how can the general public get so addicted to gambling, in a way similar to drug and many other types of addictions. This question had been solved by the study about pleasure centre, which began in 1954.

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(Graph 1: Gambling.  Author: jeniferanne Source: pictures uploaded by the original photographer)

“Pleasure center” is a part of our brain that is located below the fronted end of Corpus Callosum (As shown in Graph 2 ). When we feel happy, this area will release a chemical called “dopamine”, which is also a type of neurotransmitters that can stimulate our brains and induce the feelings of pleasure.

interhemispheric_auditory_pathways_fnhum-08-00055-g001(Graph 2: The location of corpus Callosum) Author: Saskia Steinmann, Gregor Leicht and Christoph Mulert Source: pictures uploaded by the original photographer.

The classic experiment regarding pleasure centre is “Rats and Rewards”. In 1950, two psychological researchers, whose names are James Olds and Peter Milner, implanted several electrodes into rats’ brains to release small electric pulses, which can stimulate specific areas of the brain. Olds and Milner found out that when they place the electrodes onto the location where below the fronted end of Corpus Callosum (As shown in Graph 2 ), which also known as the pleasure centre in the future, rats would keep pushing the panel without eating and drinking. In the end, these rats died from hunger and thirst. Based on this experiment, other scientists further discovered dopamine and the study of classical learning.

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This type of addictive behaviour, as exhibited by the rats in the above experiment, is very similar to gambling. It can force people to forget about their real lives and maintain their addictive activities.

However, what if we can find a type of medicine that can inhibit the production of dopamine, and to help people quit gambling? In the Centre for Gambling Research at UBC, many researchers and scientists are experimenting to develop a new type of medicine which could regulate the pleasure centre and reduce the amount of dopamine emitted. They are also researching psychological methods to examine and control decision-making. The experimental methods are mainly about giving different groups of test subjects many types of medicine, and their heart rates, hormone levels or other types of physiological signals are measured. Higher heart rates or hormone levels imply higher releasing of dopamine. Base on such reaction, scientists can test about how can a specific of medicine can lower the physiological signals, which can eventually inhibit the pleasurable feelings of addictions. If this research can be achieved, many people in the world who suffer from gambling problems can be saved and also start a brand new life.

–Xiaochen Liang

References:

What’s pleasure center and the famous rat experiment ?

http://www.neuroscientificallychallenged.com/blog/know-your-brain-reward-system

The UBC gambling research

About

Graph 1

Author: jeniferanne Source: pictures uploaded by the original photographer

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Graph 2

Author: Saskia Steinmann, Gregor Leicht and Christoph Mulert Source: pictures uploaded by the original photographer.

https://commons.wikimedia.org/wiki/File:Interhemispheric_auditory_pathways_fnhum-08-00055-g001.png

Video:

https://www.youtube.com/watch?v=ruEsLc6IaBk[/youtube] Youtube Uploaded by Kanaal van teaching psychology   Sources: Unknown

 

 

 

 

Zika Virus impairs Infant’s brain development

What is Zika? Zika is a virus passed by a bite of an infected yellow fever mosquito  (1). Adults infected with Zika virus can develop several symptoms. For instance, headache, rash, fever, red eyes and muscle pain. Indeed, not only adults can be infected by the Zika virus. Pregnant women infected with Zika virus can also pass it down to their fetus.

Joseph Gleeson,a neuroscientist from Rockefeller Univeristy in New York City,  suggested infants infected with Zika virus are very likely to be born with abnormally small heads called microcephaly (4). A group of researchers conducted an experiment to understand how Zika virus caused impairment in cerebral cortical development, an area of the brain associated with the function of thoughts and actions. First, the researchers infected both neural progenitor cells (NPCs) and mature cortical neurons with Zika virus (2). Neural progenitor cells, like stem cells, that are capable of differentiating into neural cells (3). While, cortical neurons are nerve cells found in the largest region of the brain that is responsible for the complex activities, such as thoughts, perceptions, voluntary movements and more (3). The experimental results showed there were more cell deaths in infected NPCs than mature cortical neurons. Thus, the scientists claimed the results provide a plausible pathway showing how fetus’s brain is infected by Zika virus.

Figure 1: The comparison of infant's head size without Zika virus versus with Zika virus

Figure 1: The comparison of infant’s normal head size to an infant infected with Zika virus. Author: Tani Source: Picture uploaded by original photographer

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Figure 2: The map showing the spread of Zika virus. Author: Lizzie Dearden; Source: Picture uploaded by original photographer

Zika virus has been reported to be an alarming issue in Brazil, Mexico, some areas in the United States and more (1). At this stage, there is no cure or vaccine to treat Zika virus. However, wearing long-sleeved shirts and long pants regularly can minimize the chance of getting bitten by a Zika-infected mosquito. In addition, carry insect repellent all the time is another way to avoid getting infected with Zika virus. It is strongly encouraged to consult the doctor for advice if an expectant mother is infected with Zika virus. Lastly, try to avoid traveling to areas reported with active Zika virus transmission.

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References:

1. U.S Department of Health and Human Services. Centers for Disease Control and Prevention: Zika Virus. https://www.cdc.gov/zika/about/overview.html (accessed on Oct 2nd, 2016).

2.Miner, J.J & Diamond, M.S. Cell Stem Cell: Understanding How Zika Virus Enters and Infects Neural Target Cells. Science Direct. 2016, 18, 559-560.

3. Nature. Neural progenitors. http://www.nature.com/subjects/neural-progenitors (accessed on Oct 2nd, 2016).

4. Society for Science and the Public. Brain Health: Zika can damage the brains of even adults. https://www.sciencenewsforstudents.org/article/zika-can-damage-brains-even-adults (accessed on Oct 2nd, 2016).

Photo source:

1. Copyright information: http://pregnancywellnesstips.com/pregnancy-wellness-symptoms-prevention-treatment-of-zika-virus-during-pregnancy/

2. Copyright information: http://www.independent.co.uk/life-style/health-and-families/health-news/zika-virus-uk-america-europe-symptoms-cure-pregnant-women-microcephaly-a6851126.html

The Truth Behind Silver and Titanium Oxide Nanoparticles

Commercial products, such as cosmetics and paints (4), contain titanium oxide (TiO2) nanoparticles; antimicrobial agents, fabrics, and food preservatives (5) contain silver (Ag) nanoparticles.  Nanoparticles, synthetically made molecules that range in size from 1 nm to 100 nm (5), are found in every day household items.

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Titanium Oxide Nanoparticle on Stainless Steel (Image Courtesy of Wikimedia Common; Author: Iuliia Karlagina; Source: Picture Uploaded by Original Photographer)

A recent publication in the Journal of Environmental Toxicology and Pharmacology by researchers at National Tsing Hua University in Taiwan revealed the potential risks that nanoparticles of TiO2 and Ag as well as Ag+ ions pose to the blood-brain barrier of animal cells (2). Chen and fellow colleagues (2) simulated the conditions of the blood-brain barrier in vitro. As illustrated in the figure below, the blood brain barrier is a highly selective membrane that only allows specific molecules, such as glucose and insulin, and ions to pass between the blood and the brain (1).

blood-brain-barrier

Blood-Brain Barrier (Image Courtesy of Wikimedia Commons; Authors: Helen Stolp, Shane Liddelow, Ines Sa-Pereira, Katarzyna Dziegielewska, Norman Saunders; Source: Journal Article)

The study (2) concluded that silver nanoparticles not only affect the selectivity of the blood-brain barrier, but it can lead to a higher likelihood of genetic mutations and even cell death. Due to the small size of silver nanoparticles (8.4 nm) and TiO2 nanoparticles (6 nm) (2), they were able to bypass the selective membrane and enter into the central nervous system.  Furthermore, the silver ions and titanium oxide nanoparticles can alter the permeability of the blood-brain barrier by cell-to-cell interactions, known as cytokine secretions (2). This effect is further intensified in the presence of lipopolysaccharide, which is a type of molecular marker found on the surface of gram-negative bacteria (6). Their findings suggest that when we are pre-exposed to TiO2 and/or Ag nanoparticles while fighting a bacterial infection, our bodies will elicit an immune response that can be detrimental to our brain-blood barrier (2).

This study provides a stepping stone for future studies to be performed in determining the potential health risks associated with other types of inorganic or synthetic nanoparticles, commonly found in commercial products. Personally, for the safety and well-being of people, re-establishment of national and global guidelines on the commercial use of nanoparticles is necessary.

–Gloria Kwong

References

  1. Abbott, N. J., Patabendige, A. A. K., Dolman, D. E. M., Yusof, S. R., & Begley, D. J. (2010). Structure and function of the blood–brain barrier. Neurobiology of Disease, 37(1), 13-25.
  2. Chen, I.-C.; Hsiao, I.-L.; Lin, H.-C.; Wu, C.-H.; Chuang, C.-Y.; Huang, Y.-J. Environmental Toxicology and Pharmacology 2016, 47, 108–118.
  3. Clett Erridge, Elliott Bennett-Guerrero, Ian R. Poxton, Structure and function of lipopolysaccharides, Microbes and Infection, Volume 4, Issue 8, July 2002, Pages 837-851, ISSN 1286-4579.
  4. Gupta, S.; Tripathi, M. Open Chemistry 2012, 10 (2).
  5. Rai, M.; Yadav, A.; Gade, A. Biotechnology Advances 2009, 27 (1), 76–83.
  6. Stow, J. L.; Low, P. C.; Offenhäuser, C.; Sangermani, D. Immunobiology 2009, 214 (7), 601–612.