Sudden Infant Death Syndrome and Soft Bedding

Sudden infant death syndrome(SIDS) results in the deaths of approximately 53 out of every 100000 infants. One unique aspect of SIDS is that the root cause is unknown.  In the majority of cases the infants are put to bed and are found dead in the morning with no obvious cause of death.

There are several characteristics that are associated with cases of SIDS.  Two of the most common are putting the baby to sleep on their side or stomach and the use of soft bedding in cribs.  These are commonly associated with SIDS because one of the causes may be suffocation.

Although the use of soft bedding is associated with cases of SIDS, many parents in the United States still choose to use soft bedding in their infant's cribs.  The rate of parents using soft bedding has decreased from 86 percent in the mid-1990s to roughly 55 percent in the past few years.  This rate is still alarmingly high considering that the majority of SIDS cases occur when soft bedding is used.

Several recommendations to reduce the risk of SIDS are avoiding the use of soft bedding in cribs, having the infant sleep on their back and using a firm mattress.  It is also recommended that parents avoid placing toys and pillows in the crib.



References

://health.usnews.com/health-news/articles/2014/12/01/babies-still-sleeping-with-soft-bedding-despite-sids-risk-cdc

http://sids.org/

Diagnosing dementia prior to cognitive symptoms

Memory loss, accompanied with the loss of control of everyday activities, is a scary thing to imagine. Frontotemporal dementia (FTD), a degenerative brain disease, affects behavior, language and motor control. However, as with many incurable diseases, early detection can help prepare providers and patients with the necessary tools to alleviate symptoms. A recent study has discovered that those with a specific genetic mutation, and therefore increased risk for developing FTD, show a thinning of the retina prior to any symptoms of dementia (Ward et al. 2014). Over time, researchers correlated retinal thinning with disease progression. These findings make neurological sense as the retina is directly connected to the brain through these neurons. As one of the earliest manifestations of this disease-associated mutation, this finding is a potential, less invasive, diagnostic tool to observe neuronal changes before cognitive symptoms present.

References:

Ward ME, Taubes A, Chen R, Miller BL, Sephton CF, Gelfand JM, Minami S, Boscardin J, Martens LH, Seeley WW, Yu G, Herz J, Filiano AJ, Arrant AE, Roberson ED, Kraft TW, Farese RV, Green A, Gan L. 2014. Early retinal neurodegeneration and impaired Ran-mediated nuclear import of TDP-43 in progranulin-deficient FTLD. Journal of Experimental Medicine. 211(10): 1937-1945.

Other resources:

Gladstone Institutes. 25 August 2014. Changes in eye can predict changes in brain. ScienceDaily [Internet]. Available from: www.sciencedaily.com/releases/2014/08/140825100037.htm

http://memory.ucsf.edu/ftd/overview

Need A Hit for that Anxiety?

             

            It seems fitting that while we are in the Mile High city we should talk about one of its defining characteristics.  By this I mean the overwhelming acceptance of marijuana use.  As we know marijuana has been legal for recreational use in the last few years and even longer for medical purposes.  One of the leading reasons that individuals are prescribed marijuana is for anxiety and depression-like symptoms. For many individuals this develops into costly medication in more than one facet.  However, researchers at Vanderbilt University have discovered a possibility to achieve a “natural” high and to avoid the chronic use of medical marijuana.

           

            Many individuals that use medical marijuana complain of anxiety and depression like symptoms.  These symptoms are caused by the decreased activation of cannabinoid receptors.  Cannabinoid receptors are activated by endocannabinoids, which are typically the active ingredient in marijuana.  The most common endocannabinoids is called 2-AG.  Additionally these receptors are found heavily in the ventral nucleus of the amygdala, the emotional hub of the brain. 

            The researchers at Vanderbilt University developed 2-AG knockout mouse models in order to test how to obtain this natural high without marijuana.  They did this very simply blocking the enzyme that normally breaks down 2-AG within the brain.  This research into finding substitutes for marijuana is important in these patients because their treatment is also their curse.  Research has show that chronic marijuana use down regulates the cannabinoid receptors themselves.  Thus increasing the amount of anxiety and depression without ingesting more marijuana.  This enzyme blocker is thus a more effective way to achieve the same effects of marijuana without the negative side effects.

            If this research can continue to show to give the same outcome of marijuana use is it still ethical to allow these patients to use marijuana even though it causes this “vicious cycle”?  Or should this be the patients decision as to how they want to treat their symptoms?

References:

http://www.sciencedaily.com/releases/2014/12/141201113253.htm

Is Abstinence Unhealthy?

Life for many can become cluttered and busy; focusing on careers or family or trying to remember if you left the stove on or fed the cat. For some it is easy to forget about themselves and their significant other or lack there of. So when it comes to sex, is it detrimental to your health to abstain from such acts? Or were our junior high teachers right when they said sex is bad? Well Professor Stacy Lindau of obstetrics and gynecology from University of Chicago helped clear things up.

When speaking to the audience of her seminar she asks, "Would you rather cut off your dominant hand or give up sex for life?" Surprisingly 82% said they would remove their hand, yet when an anonymous poll was taken of how many times a year people copulated the number averaged below 25. Such a low average number for such a large percentage in my opinion. Why do people think sex is so necessary? 

Well from a physiological standpoint its not. The human body can abstain from sex and still live a long successful life. It is not like food, or water, or shelter. However, sex does provide some health benefits. Studies have shown that regular sex has a protective effect on the heart, lowering the risk of heart attack in men. Other benefits include increased blood flow to the genitals and "probably" is beneficial to the immune system. But the psychological side of sex can have just as many health benefits. Sex can reduce stress levels by releasing "feel good" hormones of oxytocin and dopamine, while reducing levels of cortisol. This can, in-turn, improve sleep, increasing energy levels while simultaneously preventing Alzheimer's disease (see earlier blog post). 

The disadvantages to not having sex are mostly geared toward women I am sad to say. Not having sex can lead to atrophying of the unused vaginal or hip muscles. Vaginismus is a common condition characterized by hypersensitivity of the muscles around the opening of the vagina.

So when it comes down to it, abstinence will not kill you and a person can live a very happy and healthy life this way. Just turns out that conjugating may have some beneficial attributes

Crane, Kristine. "Is Abstinence Unhealthy?" US News. U.S.News & World Report, 7 July 2014. Web. 02 Dec. 2014. <http://health.usnews.com/health-news/health-wellness/articles/2014/07/07/is-abstinence-unhealthy>.

Have you tried E-quitting?

We all know the dangers and negative health effects associated with smoking cigarettes.  Increased risk for lung cancer, heart attack, and high blood pressure are just a few of the many negative physical impacts that smoking has on the human body.  But what if I told you that smoking could help you stop smoking?  We’ve all seen the students on campus and the people outside of bars exhaling the big clouds of vapor from the new electronic cigarettes, or E-cigarettes.  These work by electrically heating up a flavored liquid that tastes like tobacco, but lacks the harmful smoke (2).  A recent study, published at the end of October of this year, cited that E-cigarettes can be an effective method of quitting smoking.  The study shows that between two groups of cigarettes smokers, the group that changed to E-cigarettes had decreased cravings and even showed a 60% decrease in cigarette use over the eight month period (1).  This could be fantastic news as many smokers are aware of the risk associated with smoking, but find themselves unable to break the addiction and quit for good.  Could this be the tool that society uses to totally eradicate tobacco smoke?

Unfortunately, the answer is probably not.

Another study, published just a month later than the first, November 2014, shows that certain brands of E-cigarettes contain ten times the level of carcinogens as regular cigarettes (2).  Several brands showed consistent increased levels of formaldehyde and acetaldehyde.  These E-cigarettes have been considered safer since they became popular and have even gotten high levels of non-smokers to try them (2).

So unfortunately, people are moving away from the harmful effects of smoking to the potentially more harmful effects of E-cigarettes.  Proving once again that there is no easy solution to get people to stop smoking.

Adriaens K, Van Gucht D, Declerck P, Baeyens F. 2014. Effectiveness of the Electronic Cigarette: An Eight-Week Flemish Study with Six-Month Follow-up on Smoking Reduction, Craving and Experienced Benefits and Complaints. Int J Environ Res Public Health [Internet]. 11(11):11220-48. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25358095 

Kanae Bekki, Shigehisa Uchiyama, Kazushi Ohta, Yohei Inaba, Hideki Nakagome, and Naoki Kunugita. 2014. Carbonyl Compounds Generated from Electronic Cigarettes. Int. J. Environ. Res. Public Health [Internet].11(11), 11192-11200. Available from: http://www.mdpi.com/1660-4601/11/11/11192/htm

Up-and-coming vaccinations

             Vaccines are incredibly important for prevention of disease; polio, diphtheria, yellow fever, small pox, whopping cough, tetanus and measles are mostly eradicated due to vaccinations. Many new vaccinations are currently in trials for the prevention of a variety of diseases that are non-contagious. 

            One vaccine that is in the early stages of clinical trials is against breast cancer. The vaccination has had success with patients in the early stages of breast cancer by slowing the progression of the cancer. The vaccination works by targeting mammaglobin, a specific gene expressed in specifically in 80% of breast cancers. The vaccination has only a few side effects, such as soreness at the site of injection, compared to the lengthy lists of side effects that occur with most oncology medications. 

          A vaccine against Lyme disease has been effective in mice against Lyme borreliosis with no adverse effects.There is still a long time before this vaccination could be approved by the FDA, though the question becomes, who should get this vaccination once it is available? Because Lyme disease is not contagious from person to person, herd immunity is not necessary. The vaccine would be most effective if given to people that are in geographic areas of high risk, such as people living in woodsy areas in the east coast of the United States. On the other hand, someone living in a city setting will most likely not be exposed to ticks containing the bacterium that causes lyme disease.

         Both of these vaccines are far from becoming available to the general public, though the progression we are seeing with research with vaccines is promising. 

Sources:

http://www.sciencedaily.com/releases/2014/12/141201090313.htm

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4237411/

Breaking the Barrier

As we know, the blood brain barrier has extremely selective permeability to protect the microenvironment of neurons. Understandably, fluctuations in systemic blood components need to be tightly controlled to maintain the integrity of the cerebral circulation. For example, eating a protein rich meal will increase the concentration of certain amino acids that serve as neurotransmitters, causing inappropriate neuronal stimulation if there was no barrier in place (Boron & Boulpaep 2012).

The anatomy of the brain helps to select for solutes that can pass from the blood to the brain extracellular fluid (BECF). Capillary endothelial cells are found in the brain capillaries and, unlike other body capillaries, they are connected to each other by continuous tight junctions, providing the physical barrier to certain solutes (Boron & Boulpaep 2012). To reiterate, certain solutes such as O₂ or caffeine can pass the blood brain barrier due to their properties, but other molecules, such as potassium ions have a more limited access.

Capillaries of the brain. Photo credit: Dan Ferber.

Conceivably, this makes clinical treatments that would otherwise target certain brain conditions, difficult. For example, in the treatment of brain tumors, the successful passage of certain small chemotherapeutic drugs is necessary (Silva 2008). Some therapies attempt to pair therapeutic drug agents to transporters with the ability to cross the barrier, however, this is not always efficient and has the potential to cause other side effects—this emphasizes a need to explore the ability to manipulate the blood brain barrier (Silva 2008).

A recent study sought to research this particular concept, but with a completely novel approach. This new methodology involves placing ultrasound emitters in the brains of patients with glioblastoma (brain tumors). The pulses created by the ultrasound cause vibrations that separate the capillary endothelial cells in a specific region, for a specific period of time, allowing access to the brain extracellular fluid (Canney et al. 2013). This access allows for the delivery of drugs that can ablate the tumor and, in this study, allowed the barrier to remain open for up to six hours. The long term effects/success of this treatment are still being established, as the status of the tumors is still being measured; however, limited peripheral tissue damage was observed. This has huge implications, not only for administering chemotherapy, but also has been shown to reduce protein plaque in the brains of mice with a disease comparable to human Alzheimer’s (Thomson 2014).

As we know, scientific breakthroughs come in small steps and more research is necessary to better understand the success and capacity of this new ultrasound approach. What do you think about its potential? What about possible consequences to opening the blood-brain barrier for six hours?

References:

Boron WF, Boulpaep EL. 2012. Medical Physiology. 2nd ed. Philadelphia: Saunders. 298-301 p. 

Canney MS, Chavrier F, Tsysar S, Chapelon J, Lafon C, Carpentier A. 2013. A multi-element interstitial ultrasound applicator for the thermal therapy of brain tumors. The Journal of the Acoustical Society of America. 134:1647-1655.

Ferber D. Bridging the Blood-Brain Barrier: New Methods Improve the Odds of Getting Drugs to the Brain Cells That Need Them. PLoS Biology 5(6):169.

Silva GA. 2008. Nanotechnology approaches to crossing the blood-brain barrier and drug delivery to the CNS. BioMed Central Neuroscience. 9(3): S4.

Thomson H. 2014 Oct. 22. Brain barrier opened for first time to treat cancer. New Scientist [Internet]; 2922. Available from: http://www.newscientist.com/article/dn26432-brain-barrier-opened-for-first-time-to-treat-cancer.html#.VH0uNzHF-Sq

Eating Like a Caveman.

            Every week there seems to be a new trend in diet and proper nutrition. This week’s flavor is the paleo diet. Its philosophy is that we only eat the things that were available to our hunter gatherer ancestors 10,000 years ago. The main argument for this is that, over millions of years of evolution our ancestors who were genetically selected to live as hunter and gathers. Therefore modern day humans should eat as such.

            The first assumption of this is that we have a good idea of what humans ate back then. In reality we don’t really know. What we know are speculations based on location and what was found with human remains. This brings up a second excellent point; people from different parts of the world ate different things. As people and cultures developed so did the things they ate. People from Asia eat drastically different things as people from Africa.

            The biggest flaw I find with this philosophy of eating is that it assumes people stopped evolving 10,000 years ago. If this was the case we would all still be living in caves. As soon as humans developed the domestication of plants and animal, civilization began. The same logic that we evolved to be hunter and gathers has to be applied to the genetic changes caused by the development of modern society. Are the people who are better suited to live in our society more likely to pass on the genes?

            In the end there is no all-inclusive diet that is perfect for everyone. What we eat should be based on good science and not on some fantasy about a lost Stone Age paradise.

Curnoe D. 2014 Nov 30. The Palaeolithic Diet And The Unprovable Links To Our Past IFL Sceince;. Available from: http://www.iflscience.com/health-and-medicine/palaeolithic-diet-and-unprovable-links-our-past

Tackling the Blood Brain Barrier

The blood brain barrier (BBB) is a tried and true protection for the brain from all sorts of chemicals and other molecules that are in the blood.  Brain capillaries shelter the brain by forming a highly selective permeable layer that limit transport via membrane carriers and channels(2).  The lipophilic membrane keeps water soluble molecules without membrane carriers or channels from crossing the barrier and into the brain.  Early anti-histamines were lipid soluble and freely and easily crossed the BBB causing unwanted drowsiness in patients taking these drugs.  By changing the structures of these anti-histamines, making them less lipid-soluble, non-drowsy allergy medicines were developed(2).

Neurobiologists from Genentech in South San Francisco have developed an antibody capable of crossing the BBB and help limit the damage done by Alzheimer’s disease (AD).  The damage to neural function due to AD is caused by the aggregation of protein amyloid-β(1).  Amyloid-β is created by an enzyme called β-secretase 1 (BACE1).  The antibody developed by Genentech binds to an iron transporter called transferrin that typically carries iron across the BBB.  The antibody binds to transferrin, is transported across the BBB and then binds, with a higher affinity, to BACE1, blocking amyloid- β production(1).  Recent studies have shown decreases in plasma levels of amyloid- β up to as much as fifty-percent in mouse and monkey models.

As technology progresses, so will the treatment of pathologies that we previously viewed as death sentences.  As future health care workers, we will be using techniques and ideas that we now only have limited understanding of.  I am very excited to see where medicine will go, but at the same time I have to worry if the technology may ultimately pass me by.  In this career path, we will always be learning and will always be working to provide the best and most successful treatment options for our patients.

Silverthorn DU. 2010. Human Physiology: An Integrated Approach. 5^th ed. California: Pearson Education, INC. 303-305 p.

Reardon S. 2014. Alzheimer's drug sneaks through blood–brain barrier. Nature Publishing Group. Available from: http://www.nature.com/news/alzheimer-s-drug-sneaks-through-blood-brain-barrier-1.16291

Eat Yogurt, Stay Smart

            Diabetes has been on the rise in the US.  Today, more than one million people are diagnosed with diabetes every year.  As the seventh leading cause of death in the US, over 245 billion dollars has been allotted to finding better treatments and possible cures for diabetes.  These are general statistics on diabetes (not specifically type I or type II).

            Yogurt may be a possible preventative measure of diabetes type II.  A study conducted by Dr. Hu found a correlation between eating a serving a yogurt everyday and a decrease risk of having type II diabetes by 19 percent.  Dr. Hu and associates began to pool their data (originally a study trying to find links between dairy products and diabetes) with other researcher’s data and found that overall, eating yogurt had an 18 percent reduced risk of having diabetes.  These findings could conclude that one’s gut microbiota may play a role in preventing diabetes (remember that seminar article about artificial sugars?).

            Beginningin 1990, scientists have started to link memory problems and type II diabetes.  More than thirteen thousand black and white adults ages 48 to 67 were tested for their memory, reasoning, problem solving, and planning using delayed word recall, digit symbol substitution, and word fluency tests. 

            Over the following twenty years, the scientists conducted five periodic examinations, but at the end only approximately six thousand subjects left.  The scientists discovered that people who suffered from a nineteen percent greater cognitive decline compared with those who did not have diabetes.  Poor control of diabetes had an even greater decline in cognitive function compared to those who were able to control their diabetes. 

            Diabetes is linked to impaired blood circulation and the researchers suggested a relationship between memory and thinking impairment to damage in the small blood vessels in the brain.  Thus, diabetes control and prevention may help to protect against later-in-life cognitive decline. 

I am what???

You're a stereo-blind. Wait. What? When I first read those words I thought it was some sort of juvenile insult, but as I read on I became fascinated. Considering my most recent post, "Are we witnessing the next step in human evolution?" (http://physioblogology4.blogspot.com/2014/11/are-we-witnessing-next-step-in-human.html), I figure It would make sense to post about the flip side.

Stereo-blind is no more an insult than "your epidermis is showing"...It is a condition that arises from such ailments as amblyopia, strabismus, optic nerve hypoplasia. Essentially the eyes do not work together and as a result the individually sees in 2D and lacks depth perception. Other than the above conditions, currently there does not seem to be a genetic link such as a gene mutation. It is a structural abnormality and can occur in anyone.  In the picture you can see an example of a seeing in 3D on the Left and 2D on the right.

The good news is it can be corrected. Susan R. Barry not only was stereo- blind for most her life, but found a way to fix it, and see in 3D at the age of 48. 48!! How cool is that?

The funny thing is, you may be stereo-blind and not even know it! As a person gets older, one of their eyes becomes dominant. This phenomenon 

usually happens slowly and the individual does not recognize the change because they know nothing different. A key sign? You go to see "Star Wars: The Force Awakens" in 3D (or any 3D movie) and don't see any thing different. (3D movies are not worth the extra $5 anyway.)

Think you might be stereo-blind? Talk to your ophthalmologist, or take this online test (http://www.mediacollege.com/3d/depth-perception/test.html).

But seriously, if your concerned see your ophthalmologist. 

Resources:

http://www.mediacollege.com/3d/depth-perception/stereoblind.html

http://www.fixingmygaze.com/

http://www.scientificamerican.com/article/seeing-in-3-d/    

What Am I Getting Myself Into?

I would be lying if I said I never questioned my choice to pursue a career in medicine. Given the tremendous financial cost and the overwhelming time commitment, will it actually be fulfilling? How will it affect my quality of life? my personal well-being?

The numbers aren’t in my favor. Burnout – defined as a combination of emotional exhaustion, detachment and a low sense of accomplishment – is prevalent among medical students and practicing physicians alike:

• A 2008 study by Dr. Dyrbye, et al. stated a burnout rate of 49.6 percent among medical students, approximately 10 percent of whom experienced suicidal ideation
• A 2012 Mayo Clinic survey found that 45.8 percent of doctors reported at least one symptom of burnout (Shanafelt 2012).

Unfortunately, over the last decade, burnout rates seem to be trending up rather than down. In true pre-med induced hypochondriac fashion, I fear the worst.

Recent research has found that burnout increases the risk for cardiovascular disease as much as well-known factors like body mass index or smoking (Bailey 2006). Further studies also indicate an increased probability of type II diabetes, male infertility, sleep disorders, and musculoskeletal disorders (Bailey 2006). One possible malefactor: lower cortisol levels.

Cortisol is the primary hormone involved in the body’s stress-response system that helps restrain immune system reactions. Research indicates that elevated cortisol levels due to chronic stress may result in glucocorticoid resistance in which receptors no longer respond to cortisol’s stop signal (Plotnikoff 2007). Over time, cortisol levels may rebound below normal, leaving the body vulnerable to a hyperactive immune response that produces chronic inflammation (Plotnikoff 2007). Such an inflammatory process is linked to the pathogenesis of other chronic diseases, including depression, and may produce a vicious positive feedback loop.

Antioxidant supplements are said to help lower cortisol levels and may be suggested as an initial preventative measure. But it isn’t that simple. For example, a 2004 study for the Cochrane Database linked increased mortality with supplemental vitamins A, C, E and beta carotene, and selenium (Offit 2013).

The medical field can’t support a burnout rate this high and climbing, it impacts everything from quality of teaching to quality of life for physicians and increases the likelihood of error in patient care. So what do we do? What structural or systemic changes can we make to help lower these statistics?

I don’t have an answer, but let’s talk. Something’s gotta give.

References

Bailey DS. 2006. Burnout harms workers’ physical health through many pathways. Monitory on Psychology. 37(6):11.

Dyrbye LN, Thomas MR, Massie FS, Power DV, Eacker A, Harper W, Durning S, Moutier C, Szydlo DW, Novotny PJ, Sloan JA, Shanafelt TD. 2008. Burnout and Suicidal Ideation among U.S. Medical Students. Ann Intern Med. 149(5):334-341.

Plotnikoff NP, Faith RE, Murgo AJ, Good RA, editors. 2007. Cytokines: Stress and Immunity, Second Edition. Florida: Tylor & Francis Group, LLC.

Offit PA. Jun 2013. Don’t Take Your Vitamins. The New York Times [Internet]. [cited 2014 Nov 30]. Available from: http://www.nytimes.com/2013/06/09/opinion/sunday/dont-take-your-vitamins.html?pagewanted=all.

Rabin RC and Kaiser Health News. Mar 2014. A growing number of primary-care doctors are burning out. How does this affect patients? Washington Post [Internet]. [cited 2014 Nov 30]. Available from: http://www.washingtonpost.com/national/health-science/a-growing-number-of-primary-care-doctors-are-burning-out-how-does-this-affect-patients/2014/03/31/2e8bce24-a951-11e3-b61e-8051b8b52d06_story.html.

Shanafelt TD, Boone S, Tan L, Dyrbye LN, Sotile W, Satele D, West CP, Sloan J, Oreskovich MR. 2012. Burnout and Satisfaction With Work-Life Balance Among US Physicians Relative to the General US Population. Arch Intern Med. 172(18):1377-1385. 

Fact or Fiction: Women Who Room Together, Cycle Together

My roommate and I are polar opposites in many ways: she’s a tall blonde with a gregarious personality; and I’m a petite brunette who may admire J.D. Salinger a bit too much; but late one Tuesday night, we suddenly felt like sisters.

Tired, moody and PMSing, we bundled into the car in our PJs and drove to the local ice cream parlor for a salted caramel cookie crunch cure-all. In stereotypical fashion, we bemoaned the less exciting aspects of womanhood and wondered if we had fallen into sync with each other’s cycles. Naturally, we did a little digging…

The Evidence

For:

In 1971, based on a phenomenon called the Lee-Boot effect, which describes the influence of pheromones on the oestrous (reproductive hormone) cycles of mice, Dr. Martha McClintock surveyed 135 women in a college dorm to see if a similar phenomenon occurred in humans.  She found that women who spent the most time together had closer onset dates for their periods. Follow-up studies showed comparable results.

25 years later, Dr. McClintock conducted another study and found that the sweat from women in the follicular (egg maturation) phase of their cycles led other women to have shorter menstrual cycles; while sweat from women in their ovulatory (egg release) phase, lengthened the menstrual cycles of other women. She continues her work today.

Against:

Critics of the menstrual synchrony theory cite problems with studies like Dr. McClintock’s, including: flawed assumptions, unsound statistical methods, and sampling biases. In a critical review done by Dr. H. Clyde Wilson of the original McClintock study, correcting these “errors” erased the observation of significant levels of menstrual synchrony.

Furthermore, it’s hard to eliminate pure coincidence. Two women’s periods are, in fact, statistically likely to overlap. The average woman has a 28-day cycle, thus the maximum amount of time that two women may be out of phase would be 14 days. Given that information, on average, the onset of the two women’s periods would be seven days apart, and fifty percent of the time they would be even closer. Since a women’s period usually lasts for about five days, an overlap is almost to be expected!

The Verdict

Speculation remains over if, why and how this phenomenon occurs in humans. Nonetheless, some studies suggest that there is a sliding scale of sensitivity to certain pheromones, such as 5alpha-androst-16-en-3alpha-ol, which may affect the presentation of menstrual synchrony.

References

McClintock MK. 1971. Menstrual Synchrony and Suppression. Nature. 291:244-245.

Morofushi M, Shinohara K, Funabashi T, Kimura F. 2000. Positive relationship between menstrual synchrony and ability to smell 5alpha-androst-16-en-3alpha-ol. Chem Senses. 25(4):407-11.

Rudis J. 2008. True or False: Women Who Live Together Tend to Have Synchronized Menstrual Periods [Internet]. Beth Israel Deaconess Medical Center web site. [cited in 2014 Nov 30]. Available from: http://www.bidmc.org/YourHealth/Therapeutic-Centers/Womens-Self-Care.aspx?ChunkID=156991

Wilson HC. 1992. A Critical Review of Menstrual Synchrony Research. Psychoneuroendocrinology. 17(6):565-591.

Shocking...The Brain that Is

In recent years, it has become a common practice to find a machine that will replace the effects of hard work and practice. Many of these can be fond during late-night infomercials, but some lucky few have graced the pages of science literature over the past decade. One such treatment is known as transcranial direct current stimulation (tDCS). As the name implies, the goal of tDCS is to provide a low wattage of electrical impulse to the brain to help improve neuron firing (or slow it if the results are undesired) by changing the electrical environment around the neurons.

For those of you new to the physiology blog, it is important to remember that neuron firing is the propagation of an action potential down the axon of the neuron. This propagation is achieved by voltage-gated ion channels that allow for the environment within the neuron to go from a resting negative electrical environment to a positive one. Without getting into the gritty details, the message will be continued down the axon with a short delay afterward to help reset the chemical environment that helps make this axon firing possible. The idea of tDCS is that you can use electricity (hopefully in small, controlled doses) to improve the way neurons function in the brain. With persistent treatment and stimulation from the external environment the neurons might be tricked into long-term potentiation, known more commonly as learning. Like the Ab Master 3000, the end goal is that you do minimal effort to achieve maximum results. It's like giving your brain a six pack. The benefits touted include improving memory, treating depression, making you more creative, making making mental math easier and improving your reading comprehension and speed.

Now for the sad news. A group of researchers has reviewed the roughly 200 studies confirming the impacts of tDCS and found no significant results are truly confirmed in any of the studies. The disclaimer is that testing the effects of tDCS is very challenging limited only to testing associated impacts like improved blood flow to an area or how muscle contraction improves after stimulation. The results are highly variable and the controls in the studies have been called into question as well. Some in the scientific community wave this discovery of...well nothing significant as merely an inability to measure what they are sure is happening. Others believe it undermines the entire area of treatment by refuting the impacts on physiology. More research reviews are being conducted by the group from The University of Melbourne where the first was published focusing on the cognitive impacts of tDCS. The initial results have been deemed controversial at best. The moral of the story is we can't really say what tDCS does with full confidence.

If you are looking to improve the way your brain works, try practicing the skill in question. If you spent the resources you originally invested into researching and buying a DIY tDCS kit and simply practiced mental math, you would likely see the same improvements in your skills. Neuroscience is growing every day and getting closer to finding the way to grow and improve the human brain, but until then, take those few extra seconds and struggle through the mental math and create long-term potentiation for nothing but your time.


Resources:
http://www.sciencedirect.com/science/article/pii/S0028393214004394
http://www.newscientist.com/article/dn26636-has-the-brainzap-backlash-begun.html#.VHyIXIvF-Sq

Don't Like Your Genes? Pay to Trade!

The world of medicine has arrived at the point we've all been waiting for; we can finally preform gene replacement! Don't worry about the cool Million Plus Euro that it will cost you just yet because it won't be approved for sale until April 2015. The Dutch biotech company UniQure has created and tested a gene replacement regimen for lipoprotein lipase deficiency (LPLD) and long-term results are promising. 

LPLD- What is it?  

Lipoprotein lipase (LPL) is needed to break down triglycerides into free fatty acids that the body can then use. Without these necessary enzymes, the triglycerides build up in the capillaries of the digestion system and can result in serious health complications, the most common of which is pancreatitis (Inflammation and dysfunction of the pancreas which is responsible for releasing the majority of the enzymes needed to digest all food ingested). The LPLs are normally made in the muscle cells and then transported to the digestive capillaries, but with LPLD there is an error in the gene that codes for these LPLs causing either dysfunctional LPLs to be made which then get destroyed by the body’s immune system or simply not enough LPLs are made. LPLD is a rare disease impacting only a small number of people in the population.

Glybera - How Gene Replacement Works

Glybera, the commercial name of the gene replacement therapy, takes advantage of our friend the virus, alipogene tiparvovec, which is rendered harmless before use. As seen in the image (left), the new DNA for the gene that codes LPL is inserted into the virus (referred to as a vector) and the person impacted by LPLD is simply infected with the virus through a series of injections. The virus then invades the cells of the body like any other virus and begins to transcribe and translate the needed gene into the proteins that form LPLs. The alipogene virus is a great vector because the body has a minimal immune response to it that prevents it from being cleared from the body. The human trials are lasting into their 6^th year with almost zero complications and continued expression of the LPL gene.

The Major Considerations

As the first major treatment of its kind to reach the market, it will serve as a foundation that all future gene replacement approaches will be modeled after. As mentioned in the beginning the current estimated price for a 65kg patient will be around 1 Million Euro (Glybera won’t reach the U.S. until 2018 at the earliest). The pricing structure is considered valid by many in the industry and actually matches other replacement therapies that are currently employed to treat rare diseases. Other gene replacement treatments being developed for more common diseases will have a lower cost due to the larger consumer pool. The drug company is mostly concerned with recouping the huge investments that were required to develop the therapy. Only 23-30% of the cost will be considered royalties for UniQure; the rest will be to cover the expense of making the vectors themselves.

It is important also to consider the implications of the future potential of gene replacement. We aren’t to the point of changing our eye and hair color with genes yet, but as this market begins to form within the medical community, its important to remember there is always the potential for long-term impacts that don’t seem obvious. This project could bring a whole new meaning the term designer genes.   

Resources: 

http://www.uniqure.com/uploads/Publications/GL008_clinical_2010.pdf

http://news.yahoo.com/exclusive-first-gene-therapy-drug-sets-million-euro-173717146--finance.html

Image:

http://en.wikipedia.org/wiki/Alipogene_tiparvovec#mediaviewer/File:AAV_Gene_Therapy.jpg