The Truth About High Fructose Corn Syrup

In 2010, the Corn Refiners Association (CRA) began producing TV commercials defending and promoting the usage of high fructose corn syrup (HFCS) as a sweetener. What is it about HFCS that gave it a bad reputation in the first place? My guess is that it’s the “syrup” part. That word doesn’t exactly scream “healthy.” Regardless, I’ve done the research and made my conclusion about HFCS – read more for the answer! For now, check out of the CRA’s promotional advertisements:

First, let’s think about what HFCS is. What makes it different from table sugar?

In the 1970s, there were increased taxes on sugar but subsidies on corn, “making it a much cheaper sweetener than table sugar” (American Chemical Society). Using advanced chemical processes, sweetener manufactures began to break down corn into corn starch, then into corn syrup, and then into glucose, a monosaccharide (basic building block of carbohydrates). However, fructose (also a monosaccharide) is naturally sweeter than glucose, so they broke the glucose down even further. Think about it like this:

Corn diagram

Table sugar is sucrose, a polysaccharides (poly = many, polysaccharides = many monosaccharides). The connection: there’s no nutritional difference between using sucrose as a sweetener verses using fructose! My information comes from a video produced by the American Chemical Society on March 31, 2015 and seen on BusinessInsider.com just last week. Check it out here:

Does it seem like I’ve made it pretty clear that HFCS is no worse than sugar to sweeten your favorite foods? I hope so, because that was my goal. However, the topic has historically been controversial in the medical community. On his blog in 2014, Dr. Mark Hyman strongly criticizes HFCS as a sweetener option and condemns the CRA for funding a commercial campaign to promote the safety of HFCS as a viable sweetener. Hyman’s main points denouncing HFCS are two questionable claims:

  • HFCS consumption causes obesity, diabetes, and other problems
  • HFCS contains mercury

First of all, Hyman should not be so quick to shun HFCS for causing obesity. Table sugar (sucrose) does the exact same thing when overconsumed. The key is that both HFCS and sugar are acceptable sweeteners when used in moderation. HFCS is included by the Food and Drug Administration (FDA) on the list of “Generally Recognized As Safe” (GRAS) food. The FDA also states that they “are not aware of any evidence… that there is a difference in safety between foods containing [high fructose corn syrup] and foods containing similar amounts of other nutritive sweeteners with approximately equal glucose and fructose content, such as sucrose, honey, or other traditional sweeteners.”

The FDA is undoubtedly reliable, but if you would like to hear more about the claim that HFCS contains mercury, Dr. Jim Laidler explains in further detail in this short video:

http://sweetsurprise.com/hfcs-faqs#108

In addition, the video produced by the ACS and posted by Business Insider cites multiple reliable scientific journals, including a study published in Advances in Nutrition just two years ago.

The average American consumes 23 tablespoons of sugar a day, when you should consume less than 10 (According to the video)! Whether you are eating food sweetened by table sugar (sucrose) or high fructose corn syrup, the dangers of overconsumption are the same. Eat your sweets in moderation!

Sources: American Chemical Society, Corn Refiners Association, United States Food and Drug Administration, Business Insider

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Gluten: The Protein, The Trend, The Choice

In the five years since her rheumatoid arthritis diagnosis, Bailey Brislin can attest to the increase of gluten’s appearance in public discourse and on social media. A poll I conducted asking 34 random participants various questions about gluten revealed a lot about public opinion and knowledge surrounding the gluten-free trend. Collectively, it seems like these are the two opposing misconceptions about gluten:

  1. Gluten is an unhealthy component of food and should be avoided by everyone
  2. The gluten-free diet is entirely a conspiracy; no one should have to avoid gluten

Although a strong majority of the participants did not actually follow a gluten-free diet themselves, 90% knew at least one other person who did. Two-thirds of these people known to be gluten-free either had celiac disease or another gluten intolerance. Other participants listed their gluten-free friends as simply following the fad or trying “to be healthy.”

“I think people who are gluten free by choice with no medical need for it just don’t understand the science of gluten very well.” Becky Turner, a senior biology major at UNC-Chapel Hill, has often pondered with me the cause behind the growing popularity of the gluten-free diet. “Your diet is your choice, but uninformed choices are causing those who don’t have a choice to suffer from the subsequent bad reputation of being gluten-free.”

Although true gluten-free individuals like Brislin may receive criticism from a few skeptics, at least the growing trend in the gluten-free diet is increasing the number of gluten-free products on grocery shelves. In 2014, the U.S. Food and Drug Administration (FDA) defined “gluten-free” as products containing less than 20 parts per million of gluten (FDA, allergens). However, since this labeling is voluntary, there has been an increase of marketing products as “gluten-free” even though their contents have always been naturally absent of gluten (example: hummus).

Rebecca Houser, a weight-loss consultant with a degree in nutrition science from North Carolina State University, predicts the future of the gluten-free trend: “Unless you have an actual sensitivity to gluten, the hype will die down and we will move on to the next fad diet.”

So, after all of this clarification on what gluten is and who is truly impacted by it, how do we ascertain how the craze began? Ultimately, the beginning of the focus on gluten when talking about nutrition cannot be pinpointed to one study or one patient. However, it is possible and reasonable to think that technology and research have enhanced in the past decade to the point where disorders like celiac disease and rheumatoid arthritis are better understood. I hypothesize that it is this increased understanding that has led to a new light being shined upon gluten as a harmful product. When scientists were able to pinpoint gluten as a cause of illness, people with celiac disease and other gluten intolerance disorders begin to eat gluten-free as instructed by their doctors. Friends and family who heard about their lifestyle change may not have connected the aversion to gluten to become healthier with a unique medical condition. Hence, the association of “gluten” with “unhealthy.”

This, my friends, is an example of a classic health misconception. The bigger picture lesson here: ask why. If someone (not a doctor) tells you gluten is bad, do not take their word for it. Do the research yourself – be informed! And if eliminating gluten from your diet makes you feel better, that’s great! Shrug off any criticism. You know how you feel better than anyone else.

Autoimmune Disorders and Gluten Intolerance

Some medical conditions require a patient to eliminate gluten from their diet.

Celiac disease, which affects about 1% of the population of the United States (Mayo Clinic), is an autoimmune disorder based on an intolerance of gluten proteins. Autoimmune disorders occur when the immune system attacks particles that are normally not harmful to the body, either ingested food proteins or the body’s own cells.

Celiac disease occurs when the immune system attacks the body’s own cells after gluten is ingested. Specifically, the cells of the small intestine are targeted. Celiac disease-related attacks on the small intestine damage the cells that absorb nutrients during digestion (Celiac Disease Foundation).

Celiac disease is hereditary, meaning it runs in families. The pattern of inheritance is unknown (NIH). However, 95% of people with celiac disease have the same gene specific for celiac disease predisposition (Medscape, Genetics of Celiac Disease).

Rheumatoid arthritis is another autoimmune disorder relating to gluten intolerance. However, gluten is only one of many potential signals that can lead to an autoimmune attack. Rheumatoid arthritis causes inflammation of the joints – resulting in swelling, pain, and decreased movement ability (Arthritis Foundation).

Bailey Brislin, a UNC-Chapel Hill sophomore biology major preparing for medical school, was diagnosed with juvenile rheumatoid arthritis during her first year in high school. “My ankle had been swollen for months. We went to multiple doctors that couldn’t tell me what was wrong,” Brislin recalls of the time before her diagnosis. Finally, an ankle specialist ordered an MRI and referred Brislin to a rheumatologist after blood test results indicated Rheumatoid factor (RF) in her system. RF is an antibody characteristic of rheumatoid arthritis patients as well as people with other autoimmune disorders (Medscape, Rheumatoid Factor).

The next step to calculating Brislin’s proper treatment was a 5-week series of food sensitivity testing. Although the cause of rheumatoid arthritis is not fully known, potential factors triggering joint inflammation are food proteins, pathogens, female hormones, obesity, stress, and other environmental factors (Arthritis Foundation).

The results of Brislin’s sensitivity tests showed intolerance of gluten and dairy: typical occurrences among rheumatoid arthritis patients. After a while, Brislin realized that eliminating gluten from her diet had a much stronger impact on reducing  her joint inflammation than eliminating dairy.

“After a month off of gluten, I felt better. I was able to stop taking pain medication just by eliminating gluten alone,” Brislin says, “but I should be dairy-free too.” Many years later, Brislin still regularly takes immunosuppressant drugs to improve her condition.

After many years of maintaining a gluten-free diet to ensure her joint inflammation does not return, Brislin has also gathered an opinion on the growing trend of a gluten-free diet. Brislin compares people going gluten-free for no necessary reason to people trying a vegetarian diet just to see if they can do it. “There are people glorifying the gluten-free diet. It’s just bread,” Brislin says, in response to people going gluten-free for supposed “just to be healthy” reasons.

“So gluten-free becomes this very popular trend… and I get all of this criticism for being gluten-free. My rheumatologist always talks about how you don’t have to find the specific scientific data you want, just work with what has been proven in your own case,” Brislin says as she describes her encounters with gluten-free skeptics. Brislin experienced the growth of the gluten-free trend from a very unique perspective. She understands the necessity of eliminating gluten from the diet in certain circumstances but is also critical of the diet in other instances.

Her evaluation below perfectly sums up my goal in writing this series on the growing obsession with gluten:

“There are a lot of people who are very healthy who also eat gluten. I don’t think there’s anything inherently wrong with gluten – it’s not an evil food. Not eating a lot of bread is probably a good thing, but stopping eating bread and replacing it with gluten-free bread doesn’t make much sense… I’m not sure what dietary benefits people think that’s providing…”

Stay tuned for my third and last segment of my series on the gluten-free trend. This last post will contain further analysis on the development of the gluten-free trend, data from a poll of opinions about it, and an interview with Raleigh allergist Dr. Vaishali Mankad.

What is gluten?

Contrary to what you may have heard, gluten is not harmful for most people to ingest.

(0:44)

Let me set the record straight. Gluten refers to a specific set of proteins. Proteins are large molecules made up of amino acids that perform a vast range of actions necessary for life in all living organisms. In this case, gluten proteins contribute to vital life functions for the plants of wheat, barley, and rye.

The word “gluten” comes from the Latin word for glue, and rightly so. Gluten proteins are responsible for the qualities in bread such as elasticity, chewiness, and shape1. When baking bread and other products containing these proteins, the mixture thickens and rises because of thousands of gluten proteins sticking together as the temperature increases.

Foods containing gluten:

(Not a comprehensive list)

  • Pasta
  • Bread
  • Crackers
  • Baked goods
  • Cereal and granola
  • Pancakes and waffles
  • Flour tortillas
  • Beer
  • Milkshakes

While reflecting on this list, it may seem that going gluten-free could be a way to reduce fat intake and lose some weight. After all, beer and bread are notorious for contributing to weight gain. Avoiding these foods could help you lose weight, but gluten is not at all the only ingredient contributing to this circumstance. If you choose instead gluten-free substitutes for the food items listed above, you are not improving your chances at weight loss. In fact, you are more likely to gain weight by changing your diet to eating the gluten-free form of these foods.

In a study done last year in Spain, scientists looked at the nutritional differences between gluten-containing products and their gluten-free alternatives.2 Gluten-free bread was found to contain less protein, but two times the amount of fat (a lose-lose situation). Similarly, gluten-free pasta exhibited these changes, and in addition it contained more sodium and less fiber (more bad news). Cereal bars and flour followed this same trend.

Although it has been shown that food altered to be gluten-free is less nutritious than its natural form, fortunately there are plenty of naturally gluten-free options to choose from for people suffering from Celiac disease, rheumatoid arthritis, and other conditions in the realm of gluten intolerance. Fruit, vegetables, rice, corn, and potato are all naturally gluten-free options for healthy eating.1

Now that I have established what gluten is, what food it is found in, and the nature of gluten-free substitutes, hopefully your opinion of gluten has been fine-tuned. In the next part of this series about gluten, I will discuss Celiac disease as well as rheumatoid arthritis – and why people living with these conditions live a gluten-free lifestyle.

References:

  1. Gluten-Free Diet – Celiac Disease Foundation. (n.d.). Retrieved June 9, 2015, from http://celiac.org/live-gluten-free/glutenfreediet/
  1. Miranda, J., Lasa, A., Bustamante, M.A., Churruca, I., and Simon, E. March 2014. Nutritional Differences Between a Gluten-free Diet and a Diet Containing Equivalent Products with Gluten. Plant Foods for Human Nutrition. 69(410).

Image source:

berrycart.com/blog/wp-content/uploads/2014/08/gluten.png

Special thanks to Christine Rardin for the video reference!

What’s the deal with gluten?

In the last decade, the presence of “gluten-free” products has drastically increased on our grocery store shelves, TV commercials, and in our conversations. “She’s gluten free now” is a statement we hear often while catching up with friends. Why is gluten all of a sudden such a problem? What IS gluten? Should everyone eliminate gluten from their diet? All of these questions and more will soon be answered in a 3-part series of blog posts about gluten and the recently popular gluten-free diet trend. I plan to describe gluten and the foods it is naturally found in and also discuss the nature of gluten-free substitutes. Plus, look forward to exclusive interviews with UNC Chapel Hill student, Bailey Brislin, as she explains why she follows a gluten-free diet, and Dr. Vaishali Mankad, a practicing allergist at Allergy Partners of Raleigh.

Understanding the biology surrounding gluten as well as its impact on our health is important. We are constantly in search of the best diet to follow for optimal health, and the media has a huge impact on what we think will help us lose weight or be healthier.

Is eliminating gluten from your diet the right choice for you? Stay tuned to find out! 

UNC Chapel Hill joins GlaxoSmithKline in the fight against HIV/AIDS

This morning at 9:30, UNC Chapel Hill Chancellor Carol Folt, along with GlaxoSmithKline CEO Andrew Witty, announced the collaboration of their respective institutions with a shared goal in mind: finding a cure for HIV/AIDS.

Just 24 hours after leading the commencement ceremony for 6,053 UNC Chapel Hill students, Folt introduced the new company to UNC’s campus, Qura Therapeutics. Folt assured listeners that everyone involved, scientists and investors alike, will be 100% committed to the project. Folt also stressed the significance of their goal as cure science (as opposed to treatment therapies). Although the HIV/AIDS cure efforts at Qura Therapeutics are projected to last for at least a decade, Folt discussed the sense of urgency that everyone involved in the project feels on a daily basis.

GSK will be 300 years old this year, an age even greater than UNC Chapel Hill, the nation’s oldest public university. The UNC/GSK collaboration will be a 50/50 partnership, a surprising move for GSK, which already brings in millions of dollars as the second largest producer of drugs for treating HIV. In addition to words from Chancellor Folt, there were also speeches from GSK CEO Andrew Witty, NC Governor Pat McCrory, and major scientific contributors: Dr. David Margolis from the UNC School of Medicine and Dr. Zhi Hung from GSK.

Stressing the significance in working together was a common theme throughout the morning announcement. Governor McCrory also mentioned the opportunity to simultaneously “save lives and create jobs.” McCrory highly praised UNC as the top university in the state and Chapel Hill as the “capital of the research area” in North Carolina. He brought to light the significance of the UNC/GSK partnership as bringing deserved attention to the research projects conducted in North Carolina at our prestigious universities – a force to be reckoned with on the same level as in Silicon Valley, Boston, and New York. However, McCrory also reminded the audience and those watching on YouTube via a live feed that the most important priority was saving lives through curing HIV/AIDS.

The collaborative research and development model to be implemented by the fusion of efforts between UNC and GSK is a monumental move in the search for a cure to HIV/AIDS.

However, questions that remain are as follows:

How long until scientists find and produce a cure?

Will the cure be affordable and accessible to the lower classes in our nation and abroad?

There is a long road ahead. In the words of UNC professor Dr. David Margolis, “it’s time to get to work.”

 
GSK Press Release:

Enhancing an Education

Life-saving medication, innovative cancer treatments, and stem cell therapy are all amazing discoveries that began in a research laboratory. Some students may not realize that they can participate in research as early as their undergraduate years. Many students beginning their studies at UNC as natural science majors are often presumed to be bound for medical school. However, many science majors choose to spend their time preparing for a career in research and academia. The unique opportunities at many research-oriented universities provide invaluable potential experiences for undergraduates to supplement and enhance their studies in a variety of subjects. Every student should try research, whether as a potential career or as a way to gain a deeper understanding of scientific concepts.

Every semester Dr. Gidi Shemer, the Director of Undergraduate Research in Biology, holds an informational seminar on getting involved in undergraduate research at UNC. For incoming first years

Image 1 - Brittany Simpson pipettes a few microliters of broth-cultured S. aureus into a microcentrifuge tube in preparation for making diluted solutions of bacteria.
Image 1: Brittany Simpson pipettes a few microliters of broth-cultured S. aureus into a microcentrifuge tube in preparation for making diluted solutions of bacteria.

and others unfamiliar with the research field, it can be ambiguous as to what research entails. During the seminar, Dr. Shemer explains:

  • how to find a lab
  • how to get class credit for doing research
  • availability and variety of different projects going on in various departments
  • value in and opportunities present when pursuing a career in research

For Brittany Simpson, who has worked in Dr. Tony Richardson’s microbiology lab since the summer of 2014, applying biological concepts and techniques in the lab has greatly enhanced her appreciation for active learning (Image 1). Although admitting lab work is a “rather large time commitment,” Simpson shares that it is “cool to get to do the stuff you learn about in your biology classes.” Many students find lab work a helpful supplement while learning material in their science classes. Thus, involvement in research not only prepares students for their future (if pursuing graduate studies), but also enriches their current learning. One of the projects Simpson works on in the Richardson lab involves testing the anti-microbial properties of cancer drugs on Methicillin-Resistant Staphylococcus aureus (MRSA) (Featured Image).

Simpson’s inspiration for pursuing research stemmed from curiosity and uncertainty about post-graduation plans. Another undergraduate, Cory Breaux, joined a lab in the UNC Neuroscience Center after finding it as an option for work study jobs.  For two years, Breaux developed skills in DNA sequencing, immunochemohistory, tissue preservation, and animal care. Breaux appreciates his experience for “learning more about the academic scientific process and how researchers take ideas to reality.” In his statement, Breaux touches on an important aspect of engaging in research in addition to attending lectures for class. Application of ideas cannot be adequately learned and practiced through reading a textbook or flipping through a PowerPoint – rather these connections can be made through conducting experiments and facing the tribulation of trial and error techniques. Like Simpson, Breaux recognizes and appreciates this enhancement of learning.

Savannah Nunnery, a junior biology major preparing for Physician’s Assistant (PA) school, decided to get involved with undergraduate research at UNC to take advantage of the incredible opportunities that come with attending a major research university. She utilized the research directory available online to search for available student positions in genetics and molecular biology labs. Nunnery emailed a few professors explaining her background in biology and her interest in their lab’s research. She found a match and joined Dr. Gregory Copenhaver’s lab in the biology department. Currently, Nunnery is in her second semester involved in research. She works with plant model organism Arabidopsis thaliana while

Image 3: A. thaliana plants, a model organism for meiotic recombination used by Nunnery's lab.
Image 2: A. thaliana plants, a model organism for meiotic recombination used by Nunnery’s lab.

researching meiotic recombination and regulation (Image 2). Specifically, Nunnery extracts DNA, runs Polymerase Chain Reactions (PCR), and genotyping of A. thaliana. She mentions learning about PCR and gel electrophoresis techniques initially in a genetics lecture before conducting these procedures on a daily basis in the lab. “It’s an entirely different way to think and learn about biology,” Nunnery explains. “My daily research broadens concepts I learn in class from something I memorize to something I understand how to use.” As Nunnery explains, it is typical of a biology major to learn in class the steps of and probably to draw the process of meiosis, the cell division process all eukaryotes use to reduce the number of chromosomes by half. It is not as typical to extract DNA from plants to directly assess their fertility qualities based on molecular tests of a specific protein involved in meiotic recombination, which is part of Nunnery’s project.

Often the skills that make a student successful while pursuing research go past acing lecture exams. Many students find a knack for navigating the scientific process and enjoy the potential to discover new metabolic pathways or enzymatic activities beyond the classic models we learn in class. The ability to make a career out of growing our knowledge is exciting for students who enjoy understanding how life works. Many research opportunities also have clinical aspects, which might interest students who are interested in seeing the connection between research and a medical application. Simpson found value in active learning during her time in the lab, Breaux appreciated learning deeper about the scientific process, and Nunnery enjoyed the synergistic learning experience of learning in class lectures while conducting the experiments herself in lab. Ultimately, there is large value in a research career. A researcher is creative, innovative, patient, and appreciative of discovering the truth. Students should take the opportunity to partake in research as an undergraduate if possible, for no matter what career path they choose, they will always appreciate the depth of knowledge they gain from conducting their own research.

UNC students: No matter what your major is or what your career interests are, consider getting involved in research! There are so many resources available to us while attending a university with such top-notch research projects being conducted. You’ll never know who you’ll meet or what you’ll learn. See for yourself!

References

  1. Interview with Brittany Simpson. 9/30/14.
  2. Interview with Cory Breaux, 9/29/14.
  3. Interview with Savannah Nunnery. 2/9/15.

Image Sources

  1. Photo by Brittany Simpson
  2. Photo by Kara Marker
  3. Photo by Savannah Nunnery

This article was previously published in Carolina Scientific Magazine, Spring 2015. 

http://www.carolinascientific.org/

Rise of the Planet of the Apes — A Scientific Critique

“Rise of the Planet of the Apes” told the story of a researcher who, while looking for the cure to Alzheimer’s, inadvertently created an army of highly intelligent primates (whoops) by developing a virus that allowed brain tissue to heal itself. The scientist, played by James Franco, had personal reasons for developing the cure; his father, living with him at home, was visibly suffering from Alzheimer’s.

Throughout the film, many of the details involving the miracle virus are vaguely expressed, but the film does adequately show a difference in how the chimpanzees and humans are differentially affected by the virus when infected. Thus, this film is a fine representation of the difficulties of applying animal model research in the lab. Moreover, this film uses topical knowledge of the pathogenicity of Alzheimer’s combined with the more widespread knowledge of the visible, debilitating effects of the disease to develop a dramatic science-fiction story with just enough realistic explanation of scientific phenomena to make the story seem plausible in real life.

Alzheimer’s disease is a neurodegenerative disorder occurring in nearly 5% of the elderly population worldwide (Bali et. al, 2010). The disease develops over time as neuron cells die, and ultimately presents clinically with memory loss and cognitive impairment (Castellani et. al, 2010). Current studies in Alzheimer’s therapy revolve around prevention: recognizing particularly susceptible groups and taking steps to slow the onset of the disease. Specifically, amyloid-β treatments are utilized since deposits of these peptides are often visible many years before patients show symptoms of Alzheimer’s (Reiman 2013).

James Franco and his scientist buddies, while looking for a cure to Alzheimer’s, infect chimpanzees with an experimental virus to examine how it impacts brain tissue and intelligence. Promising results show infected chimps succeeding at the so-called “Lucas Tower” – an actual laboratory test called the Tower of Hanoi. This test is used in real life in various studies, and it measures cognitive abilities based on skill learning and mastery (Schiff and Vakil, 2015). In the film, improved intelligence (based on a “good” Lucas Tower score) of the chimps is understood to supposedly highlight potential brain-healing qualities of the drug in humans. However, this mechanism is not particularly explained, just assumed. My critique of this particular detail is this: although new brain cells may develop in chimps infected with the drug and subsequently enable them to perform higher level functions, there is no assurance that this same mechanism will revitalize dead neurons in a human brain plagued with Alzheimer’s.

The scientist’s father shows the accurate signs of Alzheimer’s. He has trouble using silverware while eating, remembering piano tunes, and he is unable to drive. Complications occur in the lab, and the scientist eventually finds himself running unofficial, experimental human trials on his father using the virus. The Alzheimer’s-stricken old man receives an injection before bed and is heard flawlessly playing old piano tunes just a couple of hours later after waking up. Although there is no current complete cure to Alzheimer’s in existence to compare this phenomena to, it is still hard to believe that such a monumental improvement would occur within the man’s brain overnight with such visible effects. Alas, the quick change certainly instills a strong feeling of fulfillment and human victory over misfortune amongst the film’s audience.

In addition after the lab complications, the scientist takes home a baby chimpanzee (Caesar) that is found to have received the virus in utero, his mother being one of the chimps showing increased intelligence after infection with the virus. Although some viruses like HIV and herpes are known to cross the placenta during pregnancy or transmitted during birth, the movie did not provide enough detail about the virus to be able to say whether this transmission would be plausible or not. As the scientist’s father responds to the virus with restored cognitive abilities, the chimp responds to its presence in his body by showing abnormal, high-intelligence behaviors for a monkey: quick learning of sign language, humanistic qualities like holding and drinking from cups, and general adaption to a human environment.

Although the chimp continues to get smarter (and cause more problems), after a while the old man regresses back to showing symptoms of Alzheimer’s. The scientist associates this problem to his father’s immune system producing antibodies against the anti-Alzheimer’s virus. It is unclear in the film how long the virus is effective before the body responds by attacking it. It seems like in order for an immune response to be plausible it would have had to occur within a few days of the man receiving the virus. Another discrepancy is this: another scientist in the lab is accidentally exposed to the virus during a chimp experiment and dies. The infection causes some hemorrhagic disorder that was clearly not present in the old man (although he ends up dying as well since the virus stops being able to cure his Alzheimer’s). Lastly, the chimp infected with the virus neither develops the hemorrhagic disorder nor builds up antibodies against the virus. These discrepancies are strangely not addressed and slightly frustrating to someone with a scientific mind.

Despite the vague details of some biological aspects and the mentioned inconsistencies, the foundation of Alzheimer’s as the scientist’s initial motivation for most of the drama that occurs is powerful and relatable. As the generation of senior citizens increases, there a larger high-risk group for Alzheimer’s, and many people my age and older are likely to experience their grandparents or parents suffering from this unfortunate disease.

The next time you watch a science-fiction movie consider the plausibility of the science discussed in the plot. The majority of science-fiction films you will watch won’t have any scientific basis at all, but one of the coolest parts of this film is that a biologist like myself, however visionary, can see a future in brain-healing Alzheimer’s therapy. I am less convinced that vengeful apes will congregate, learn to speak and take over the world, but… I digress.

Check out the Rise of the Planet of the Apes trailer here:

Note: I originally wrote this review for my Molecular Basis of Disease class at UNC.

References

  1. Bali, Jitin; Halima, Saoussen; Felmy, BoasView Profile; Goodger, Zoe; Zurbriggen, SebastianView Profile; et al. Cellular basis of Alzheimer’s disease. Annals of Indian Academy of Neurology, suppl. Suppl 213 (Dec 2010): 89-93.
  2. Castellani, Rudy J.; Rolston, Raj K.; Smith, Mark A. September 2010. Alzheimer’s Disease. Disease-a-Month. 56(9): 484-546.
  3. Reiman, Eric M. January 2014. Alzheimer’s disease and other dementias: advances in 2013. The Lancet Neurology. 13(1): 3-5.
  4. Schiff, Rachel; Vakil, Eli. 2015. Age differences in cognitive skill learning, retention and transfer: The case of the Tower of Hanoi Puzzle. Learning and Individual Differences. Accessed Online.
  5. Picture Link: http://www.dvd-ppt-slideshow.com/blog/wp-content/uploads/2011/08/rise-of-planet-of-the-apes-4.jpg

How should you dry your hands?

One of my passions surrounding “biological awareness” so-to-speak is proper hand-washing behavior (see my BuzzFeed article – http://tinyurl.com/BacterialResistance). The perspective I want to take today, however, is actually the practice of drying hands after washing them. What is the best way to dry your hands post-cleansing? *My perspective of “best” = most sanitary*

Let’s look at some common options:

  1. Hand dryer
  2. Paper towels
  3. Cloth towel

Let’s go ahead and knock out that last option. Cloth towels are infamous for quickly becoming cesspools of germs like Coliform bacteria and Escherichia coli (1). E. coli is an infamous pathogen known for playing a role in cases of food-poisoning. Coliform bacteria are a group of bacteria commonly transferred by fecal contamination. These bacteria alone are not highly pathogenic, but their presence indicates a high incidence of other more dangerous germs that are similarly transmitted.

Poor hand-washing techniques exacerbate the colonization of these microorganisms. When microorganisms colonize, they are growing into communities of germs that are derived from a common ancestor and are increasingly resilient as they grow into larger numbers.  If one person does not adequately scrub their hands with soap and remove all dangerous infectious agents while washing, these leftover germs are transferred to the cloth towel. Also, since hand towels will realistically remain moist during the majority of their existence, essentially the perfect environment is created for many bacteria to grow and thrive until the next person comes along to dry their hands. Little does this person know, all progress made moments ago at the sink are erased (and potentially made worse) by re-infecting your hands with the germs harbored by the towel.

Our next option: utilizing hot air and friction (by rubbing your hands together) under an automatic hand dryer. This may seem like the best option because often you do not have to press a button or touch anything else after cleaning your hands. The preferred hand dryer is motion-activated and effectively dries your hands in 45 seconds. UNC Chapel Hill pharmacy student and science enthusiast Tim Angle is convinced that the warm air from these dryers is generated from a place swarming with bacteria. “Air dryers distribute bacteria due to their moist, warm environment that is prime for growing bacteria,” Angle explains. However, back in 2000, scientists showed that the air emitted from hand dryers is in fact just as sanitary as paper towels (2). In addition, in 2012, a group of researchers found that the air leaving a hand dryer actually had fewer microorganisms than the air entering it (3).

Nevertheless, Angle is still correct about the capability of warm air hand dryers to spread bacteria. This seemingly flawless method of using air to dry just-washed hands is still, in some ways, faulty. According to an article by three scientists comparing the hand-drying efficacy of various methods, warm air dryers and jet air dryers are more likely than drying hands with paper towels to spread potentially infectious droplets to the environment (4).

Dr. Christy Esmahan, a molecular biologist, brings up another flaw of warm air hand dryers. “It takes so long that people tend to leave with their hands still moist — a magnet for fresh germs.” Just like a wet cloth towel provides a fruitful breeding ground for germs, still-wet hands provide the same environment, especially when people leaving a restroom are highly likely to touch door handles and cell phones within seconds.

Considering my strictly sanitation focus, paper towels could very well be the best method for hand drying. One-time use greatly decreases risk of contamination in comparison to cloth towels. In addition, using paper towels includes the same benefit of frictional removal of bacteria as rubbing hands under a warm air dryer, while eliminating the high incidence of spreading potentially contaminated droplets to the environment.

hand drying preferences chart
Image 1: A Random Survey of Hand-Drying Preferences

Indeed, in a study of 47 random participants, a large majority preferred paper towels to warm air hand dryers (Image 1). However, the evidence for the sanitation of paper towels may not be enough to convince the large number of environmentally-concerned citizens to abandon warm air hand dryers and cloth towels. 63% of people preferring hand-drying methods other than paper towels mentioned reduction of waste as the main motivation for their choice. In addition, although the large majority of the surveyed participants did choose paper towels as their hand-drying method of choice, only 25% of those participants mentioned cleanliness and sanitation as their reasoning. 25% rationalized their choice with speed and efficiency.

Therefore, the concluding question seems to be not only “Which method is the most sanitary?” but also “How should the most appropriate method be communicated?” and, thinking holistically, “Should we be more concerned about sanitation or waste reduction?” Those who are biologically biased will likely continue to clash with the environmentally-minded. However, potential future projects that could bring the two fields together could revolve around biodegradable paper towels, for example. Ultimately, the question you should be asking yourself after reading this article is this:

What will it take to change YOUR daily hand-drying habits?

References

  1. Gerba, Charles P., Tamimi, Akrum H., Maxwell, Sherri, Sifuentes, Laura Y., Hoffman, Douglas R., Koenig, David W. 2014. Bacterial Occurrence in Kitchen Hand Towels. Food Protection Trends. 34(5): 312-317.
  2. Best, E.L., Parnell, P, Wilcox, M.H. December 2014. Microbiological comparison of hand-drying methods: the potential for contamination of the environment, user, and bystander. Journal of Hospital Infection. 88(4): 199-206.
  3. Huang, C., Ma, Wenjun, Stack, Susan. 2012. The Hygienic Efficacy of Different Hand-Drying Methods: A Review of the Evidence. Mayo Clinic Proceedings. 87(8): 791-798.
  4. Tayler, J.H., Brown, K.L., Toivenen, J, Holah J.T. December 2000. A microbiological evaluation of warm air hand driers with respect to hand hygiene and the washroom environment. Journal of Applied Microbiology. 89(6): 910-919.

Important Links

https://www.ChristyEsmahan.com

Agrobacterium: A Biological Syringe

Plants, just like humans, fall victim to bacterial infections. Dr. Ann Matthysse, a researcher in the Department of Biology at the University of North Carolina, has studied interactions between plants and pathogens since 1970, when she thought that Agrobacterium tumefaciens might lead to advances with cases of human cancer.

Matthysse initially thought that A. tumefaciens, a Gram-negative, rod-shaped bacterium found in upper layers of the soil, could be a model for cancer because it causes tumors in plants (Figure 1)

She found instead that the cancer-causing mechanism utilized by A. tumefaciens has virtually nothing to do with human cancer. However, continuing studies with the bacterium is still very beneficial due to its unique initial surface reactions with wounded plants as it binds them to begin infection.

Matthysse describes A. tumefaciens as “a biological syringe” because its virulence comes from a transfer of DNA upon infection of a plant wound, a process unique to this specific plant bacteria2. The transferred DNA integrates into the host cell chromosome and transforms the plant’s cells into tumor cells. These transformed cells then make metabolites that only A. tumefaciens is able to utilize as an energy source. The virus essentially taps into the host plant’s energy source in the same way a cell phone charger would pull energy from your car battery. This results in smaller fruit than normal being produced by the plant host, but it is usually not fatal to the plant unless the tumor blocks its main vascular tissue. Additionally, these initial surface interactions involved in DNA transfer will function the same even if non-natural, specifically-selected genes are inserted into the bacterium for transfer into a plant.

Now, Matthysse is interested in manipulating this mechanism to more efficiently develop genetically engineered crops. Some crops have been difficult to engineer, but these problems can be alleviated by identifying restrictions on the host range for agrobacterium. “Because if we knew what [these factors] were,” she proclaims, “it might be possible to counteract them.”2 If A. tumefaciens can be manipulated to bind to these plants like it does to other plant hosts, one could engineer some of these crops. For example, one could transfer genes that resist pathogenic fungi, and there is opportunity to improve nutrient levels in certain foods. “For example, rice that contains a lot of vitamin A, which would be good for people in India that don’t have a lot of vitamin A in their diet, has been made by putting the genes for vitamin A biosynthesis into rice.”

In 2006, the Centers for Disease Control and Prevention (CDC) reported that an Escherichia coli outbreak occurred from the bacteria infecting salad vegetables and causing disease in those eating the vegetables raw (Figure 2). In the numerous studies that were based on the results reported, Salmonella was also identified as a cause of disease through a similar route. E. coli was traditionally used in the lab as a control for the A. tumefaciens experiments because it did not bind to the plant host, so E. coli studies quickly began. Matthysse found that salad leaves and sprouts encountered bacteria in multiple situations:  contamination of irrigation water or equipment, improperly prepared manure fertilizer, and in post-harvest situations. Once the bacteria are bound, they cannot be removed simply by washing; infected sprouts and fruits that are not cooked prior to eating pose the greatest risk for transferring the disease to humans.

It turns out that the signals produced by the plant cell stimulate bacterial binding for A. tumefaciens, E. coli, and Salmonella. There are multiple ways that A. tumefaciens,  E. coli, and Salmonella appear to be binding to alfalfa sprouts and other salad vegetables. However, studies show that there might be a single sensory pathway that could be blocked so the bacteria are unaware of the presence of a plant in their vicinity. Thus, although the bacteria are ultimately unable to be removed once bound to the plant tissue, the sensory pathway approach could bypass this problem and prevent the bacteria from ever binding in the first place (Figure 3). Currently, Matthysse is looking at multiple methods of blocking/changing signals from plants and/or altering signal receptors on pathogenic bacteria. It might be possible to manipulate the environment so that sensory genes are turned on too soon or too late, and thus attachment and infection are not as effective.

The future of these studies remains promising, and Matthysse acknowledges the difficulty and importance of designing the most effective experiments:  identifying which factors matter the most, pinpointing the best incubation time, appropriating growth temperatures, and other conditions are a serious time investment. Practicality also has to be considered in this situation; increasing costs to customers is not a helpful option when considering long-term reduction in E. coli and Salmonella infections in raw salad vegetables. Eating leafy greens has always seemed very healthy and beneficial to the human diet, but these foods are just as prone to contamination as others. It is probably not common to consider the conditions of our salad, given that it is purchased from a seemingly safe grocery store. “We have all gotten so far away from where our food actually comes from,” Matthysse says.

Ultimately, Matthysse’s studies could lead to revolutionary improvements in genetically modified foods, and the possibilities for utilizing the A. tumefaciens gene transfer mechanism are endless. Her experiments to prevent the binding of pathogens like E. coli and Salmonella to salad vegetables could significantly reduce the number of outbreaks of these pathogens. Understanding these complicated interactions will continue to provide a strong foundation for future studies of plant pathogens.

Escherichia coli, a Gram-negative bacterium widely studied in the lab as a model organism and also found in cases of food poisoning
Figure 2: Escherichia coli, a Gram-negative bacterium widely studied in the lab as a model organism and also found in cases of food poisoning
Attachment of Agrobacterium tumefaciens to tomato root hairs. The decrease in binding visible from (A) to (B) is a comparison of wildtype A. tumefaciens (A) to A. tumefaciens without the attachment mediating gene, UPP(B).
Figure 3: Attachment of Agrobacterium tumefaciens to tomato root hairs. The decrease in binding visible from (A) to (B) is a comparison of wildtype A. tumefaciens (A) to A. tumefaciens without the attachment mediating gene, UPP(B).
Dr. Ann Matthysse, Professor of Biology, University of North Carolina at Chapel Hill.
Dr. Ann Matthysse, Professor of Biology, University of North Carolina at Chapel Hill.

References:

  1. Ann G. Matthysse; Frontiers in Plant Science 2014, 5, 1-8.
  2. Interview with Ann G. Matthysse, Ph.D. 9/18/2014.
  3. Update on Multi-State Outbreak of E. coli O157:H7 Infections From Fresh Spinach, October 6, 2006. http://www.cdc.gov/ecoli/2006/september/updates/100606.htm. (accessed September 22, 2014).

Image Sources:

  1. A. tumefaciens and E. coli: Public Domain
  2. Figure 3: Ann Matthysse

This article was previously published in Carolina Scientific Magazine, Fall 2014.