Category Archives: Science Communication

BPA: Can we limit our exposure?

Here we are, yet again, discussing BPA and the effects of exposure to the nasty chemical. BPA (bisphenol A) is a chemical which mimics estrogen in the human body. It has been linked to cancer, cardiovascular disease, sterility, diabetes and recently: obesity (Wikipedia, 2012). Not only has the chemical been found to be harmful when ingested, it has also been discovered to have a high dermal absorption coefficient; in other words, it is easily absorbed by the skin. So why is it still being ingested by millions of people and estimated to be present in 93% of us? (Prosolia, 2012)

The Canadian government was the first to recognize BPA as a toxin in 2010 and the United States’ FDA finally followed suit this year and banned the use of the chemical in baby bottles and sippy cups (The New York Times, 2012). Unfortunately, BPA is still being used today as a lining for aluminum cans (Science Daily, 2012). Many companies have recently added the tag ‘BPA free’ to their products to keep consumers buying, but are we really aware of the amount of BPA we ingest daily and how to prevent it? Did you know that the new plastic Canadian bills have the highest BPA levels measured in comparison to 9 other countries’ currencies? Research suggests the BPA content in thermal paper rolls, such as those used to print receipts in retail stores, can be passed onto bills simply by contact (Prosolia, 2012).

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The epidemic of obesity in children and adolescents, and its potential causes, has been widely talked about but it has not yet been tied to a specific environmental chemical. A recent study has made history by being the first to use a nation-wide sample of children and adolescents to observe a correlation, if any, of BPA with obesity. The sample size was 3000 children and adolescents between the ages of 6 and 19. The participants were randomly selected to have urine analysis of BPA concentration in order to find any correlation between their BPA levels and obesity. The significant finding: white children and adolescents with high BPA concentrations in their urine were 2.6 times more likely to be obese over those with low BPA concentrations. According to researchers, these results are significant enough to show a correlation between BPA levels and obesity, but the direct process of how the chemical may affect obesity, if in fact it does, is not known.  The study was well controlled, making sure to account for everything from caloric intake to the chance of other phenols, such as soaps and sunscreens, being the cause for correlation. The researchers suggest that the best way to limit BPA exposure in children would be to eliminate it from aluminum cans (Science Daily, 2012).

http://www.calgaryherald.com/life/Study+finds+connection+between+cans+bottles+childhood+obesity/7259888/story.html (accessed September 18, 2012)

Whether BPA attributes to obesity or not, there has been enough research done to show its harmful effects. Why isn’t it banned from all products used in food production? Or banned completely due to its ability to be absorbed so easily by the skin? I am proud of Canada for being the first nation to recognize BPA as a toxin and to eliminate it from baby products, but why is it still being fed to children, adolescents and adults? So much more needs to be done.

-Kady McCappin

Sources:

Science Daily. “Higher Levels of BPA in Children and Teens Significantly Associated With Obesity.” http://www.sciencedaily.com/releases/2012/09/120918111125.htm (accessed September 18, 2012)

The New York Times. “F.D.A. Makes It Official: BPA Can’t Be Used in Baby Bottles and Cups.” http://www.nytimes.com/2012/07/18/science/fda-bans-bpa-from-baby-bottles-and-sippy-cups.html?_r=0 (accessed September 18, 2012)

Wikipedia. “Bisphenol A.” http://en.wikipedia.org/wiki/Bisphenol_A#Canada (accessed September 18, 2012)

Youtube. “Uncovering Bisphenol A – Covert Depopulation.” https://www.youtube.com/watch?v=tFPXxSmLZgE&feature=related (accessed September 18, 2012)

Prosolia. BPA In Currencies:

  1. Chunyang Liao and Kurunthachalam Kannan, High Levels of Bisphenol A in Paper Currencies from Several Countries, and Implications for Dermal Exposure , 2011, Environ. Sci. Technol. In press.
  2. Wolfgang Volkel, Nataly Bittner, and Wolfgang Dekant, Quantation of Bisphenol A and Bisphenol A Glucuronide in biological samples by High Performance Liquid Chromatography-Tandem Mass Spectrometry, Drug metabolism and Disposition, 2005, 33:1748–1757.

Drug-Free: Treatments for Obstructive Sleep Apnea induced Hypertension

Obstructive sleep apnea (OSA) is a sleeping disorder,and is a highly common problem that occurs during the different cycles of sleep, which has been largely associated with the amount of stress that is exerted on the body. The disorder stems from the recurrent episodes of partial or complete upper airway obstruction during sleep. The vast majority of the people are usually not aware if they have OSA, and these cases are often left untreated for long periods of time, most of which can lead to chronic diseases in the mid 50’s and over the age of 65. OSA has been recognized as the second most popular cause of hypertension, also known as high blood pressure. Hypertension is characterized by the elevation of blood pressure in the arteries, which requires the heart to pump harder and increase the rate of contraction to get blood around the body. The most popular method for treating OSA with hypertension is through pharmaceutical drugs, which includes fluoxetine, tryptophan, and protriptyline; however, these treatments are not as effective as experts say. I argue that drug treatments for OSA and hypertension are ineffective, instead combining multiple treatments such as spine adjustment, physical intervention of nasal airway, and pharyngeal exercises will provide better results in relieving OSA and lowering hyptertension.

YouTube Preview Image This is an overview of OSA. (Krames Patient Education)

For most people who want instant relief from the effects of OSA, over the counter drugs or prescribed drugs are the most common solutions; however, according to studies done by Laurent Stephane from the University of Paris, treatment of OSA and hypertension by antihyptertensive drugs with promising preclinical results have been more difficult and less productive than what the results show. The study composed of  relatively new novel drugs that have entered preclinical trials. However, these drugs are just actually improvements on the previous generations of drugs such as neutral endopeptidase, which acts as an inhibitor for endopeptides. From the extensive tests done on these drugs on rats, there is a low accountability of the drugs producing desired effects. The article even suggests that surgery has been the favored treatment for hypertension, along with the rehabilitation of oral exercises and developing healthier lifestyles.

Fig. 1 This is the structure of aldosterone synthase inhibitor, which is a drug used to treat hypertension. (Antes et al., 2011)

One way of treating OSA is by EPAP (expiratory positive airway pressure) devices; they are placed in each nostril, and have two small valves that remain open on inspiration, but offer resistance to expiration. This device is concocted from extensive studies done on the upper-airway cross-sectional areas by CT scans during respiration. In order to reduce hypertension symptoms, there is another method other than surgery called deep brain stimulation. This treatment is relatively new, however, has promising results. The stimulation on the brain is done by placing electrodes at regions where blood pressure is controlled, and electrical pulses are sent to the brain to inhibit pressor regions. The result is that there is a decrease in the amount of blood needed in certain areas of the body, thus decreasing the amount of contraction the muscles need. Another way of treating OSA is by spinal adjustments, which can be performed by either physiotherapists or chiropractors. Pharyngeal exercises such as singing have shown improvements in OSA patients with hypertension.

Fig. 2 This picture shows how valves on EPAP devices regulate air flow (Doshi et al., 2012)

Fig. 3 The EPAP device is placed in the opening of the nose, and covers the entirety of the nose. ((Kryger et al., 2011)

In this world where everything can be solved by the intake of drugs and antibiotics, the demand of these drugs is always increasing. However, we must ask ourselves, are drugs the only way to solve everything? Through more research and developmental treatments, OSA can be effectively treated by managing a healthier lifestyle along with corrective surgery or EPAP devices, which can reduce the risks and problems of hypertension.

Sources:

Amaro, C. S., Amodeo, C., Bortolotto, L. A., Drager, L. F., Gonzaga, C. C., Paula, K. G., Pedrosa, P. P. &  Sousa, M. G. (2011). The most common secondary cause of   hypertension associated with resistant hypertension. Hypertension, 11(59), 811- 817.

Esler, M., Laurent, S. & Schlaich, M. (2012). New drugs, procedures, and devices for hypertension. Lancet, (380): 591–600.

Video link:

https://www.youtube.com/watch?v=wk8c4rNrQ-A

Websites used:

http://bioinf.mpi-inf.mpg.de/ccb/

http://www.sleepdt.com/provent-nasal-epap-a-skeptic-turns-believer/

http://www.sleepdt.com/a-novel-non-prescription-nasal-epap-device-theravent-to-treat-snoring/

 

Wave Goodbye to Shots: The Future of Drug Administration

A breakthrough by MIT Engineers is making waves in medical drug administration- literally. Previous studies explored using low ultrasound frequency waves rather than a shot or pill to deliver drugs. How is that possible? The ultrasound waves make the skin more permeable allowing drugs to be administered directly on to and passively through the skin. Results of these studies, however, have been lacking.  What researchers have now discovered is the key to success is a combination of both a low and high frequency wave.

Why bother with area of research when we already have pills or shots to give us vaccines or drugs? The possible use of this technique has huge implications on how medicine is produced and administered in the future. Not only is this drug delivery painless, but also direct and noninvasive to the skin.

Watch the video below where Carl Schoellhammer, one of the lead researchers, explains how this technique works:

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Youtube video from user MITNewsOffice

To summarize: a high and low frequency create tiny bubbles in a solution, which implode causing jets of water to remove the very top layer of skin. Drugs are able to be applied via patch or as the fluid the bubbles are created in.

What does this mean for the future?

Image from Google

On a broader scope, if the ultrasound device is made easily available and affordable for wide spread use in hospitals, the need for needles could be hugely reduced. Needle free drug delivery could potentially be more sterile and safer. It could reduce the degree of negative effects or injury from contaminated or damaged needles as well as the dangerous waste of used needles. This change in medical procedure could specifically have a huge effect on third world countries concerning sterility and treatment problems.

Insulin uptake after single freq (blue) and dual freq (red) treatments. Adapted from: Schoellhammer, C. M., et al, 2012

On a smaller scale, practical use of this treatment in the future could changethedaily life and health of diabetics. The two compounds a study used were glucose and insulin, and the results showed that they were successfully delivered passively through the skin.

Eventually, this ultrasound technique could just become an alternative for those who are uncomfortable with swallowing pills or can’t tolerate needles. I, for one, have a vested interest to see where this treatment goes in the future. Because, really, who doesn’t dread getting a shot from the doctors?

– Rachel Chang

References:

Canadian Center for Occupational Health and Safety : http://www.ccohs.ca/oshanswers/diseases/needlestick_injuries.html

Johnson, M.E. et al. “Synergistic effects of chemical enhancers and therapeutic ultrasound on transdermal drug delivery.” J Phram Sci. 12 June. 2012. Web. http://www.ncbi.nlm.nih.gov/pubmed/8818988 (accessed Oct, 1, 2012)

MIT Media Relations. “Getting (drugs) under your skin.” http://web.mit.edu/press/2012/ultrasound-waves-and-drug-delivery.html (accessed Oct, 1, 2012)

Ogura, M. et al. “Low-frequency sonophoresis: Current status and future prospects.” Adv. Drug Deliv. Rev. 3 Aug. 2008. Web. http://www.sciencedirect.com/science/article/pii/S0169409X08000860 (accessed Oct, 1, 2012)

Polat, B.E. et al.”Transport pathways and enhancement mechanisms within localized and non-localized transport regions in skin treated with low-frequency sonophoresis and sodium lauryl sulfate.” J Pharm Sci.10 Aug. 2011. Web. http://www.ncbi.nlm.nih.gov/pubmed/20740667 (accessed Oct,1, 2012)

Schoellhammer, C. M. et al. “Rapid Skin Permeabilization by the Simultaneous Application of Dual-frequency, High-intensity Ultrasound.” J. Control. Release. 22 Aug. 2012. Web. http://dx.doi.org/10.1016/j.jconrel.2012.08.019 (accessed Oct,1 , 2012)

Image source: http://www.europarl.europa.eu/resources/library/images/20081030PHT41044/20081030PHT41044_original.jpg

Schoellhammer, C. M. et al. “Rapid Skin Permeabilization by the Simultaneous Application of Dual-frequency, High-intensity Ultrasound.” J. Control. Release. 22 Aug. 2012. Web. http://dx.doi.org/10.1016/j.jconrel.2012.08.019