By Erik Schiferle
Editor Sophie Park
Parkinson’s disease is classified as a degenerative disorder of the central nervous system that results from the deterioration of cells that produce dopamine within the Substantia Nigra–a region within the middle of the brain that is associated with pleasure, addiction, and movement. Symptoms seen within early stages of the disease can include tremors, rigidity, stiffness of the limbs and body, bradykinesia (lethargic movement), and lack of coordination. Symptoms worsen over time to the point where patients may have difficulty with daily activities. Later stages of the disease may also be marked by an increase in depression or emotional instability.
Currently, there is no cure for Parkinson’s disease, but various treatments may help alleviate its symptoms. Some patients opt to undergo surgery. Surgery might involve deep brain stimulation, which utilizes electrodes implanted into the brain to provide a high frequency impulse of electricity. This removes some of the brain tissue thought to induce symptoms. However, most patients choose to make changes in lifestyle and begin medication treatment.
Medications reduce the symptoms of Parkinson’s disease, but they require patients to take multiple doses throughout the day and may be difficult to keep track of. Consequently, it is not uncommon for patients to miss a few doses. If one were to miss a dose, the patient would unpredictably undergo a range of symptoms that otherwise would have been prevented via medication. In addition, the fact that the medication’s effects only last a few hours (hence the hourly doses) causes patients to experience minor tremors before taking the next dose. Overall, this results in a 24-hour cycle with periods of stability peppered with brief periods of tremors.
In response to these problems, the bioengineer Dae-Hyeong Kim and other researchers from Seoul National University in South Korea have developed a flexible patch that automatically administers medications. Made of silicone or plastic onto which circuits are printed, the patch operates using tremor-detecting sensors to monitor medication levels. The sensors utilize a “resistive random-access memory” to keep track of the patient’s tremors over time. The sensor, upon detecting low medication levels via tremors, delivers smaller amounts of medication as needed through silica nanoparticles. As a result, the patient should firstly never miss a required dose of medication, and secondly, patients should not undergo intermittent periods of tremors due to the fact that the medication is administered when biologically necessary.
Though exciting to many, this product is still in its early developmental stages. The patch is still built by hand in one of Kim’s university laboratories. Another issue is that flexible batteries and processors do not exist for skin electronics, so the patch relies on an external power source and processor. However, Kim and his associates have proposed that smart phones or watches could be the solution to this problem. Similar to wireless phone chargers seen in stores today, the smart object would charge the patch through inductive charging, which uses an electromagnetic field to transmit energy from one object to the other. The smart object would then also serve as a processor that could send information wirelessly. Kim hopes to have the patch ready for large scale production within the next five years–he even hopes to make this “smart skin” patch a little more fashionable for patients.
By Julia Zeh
The Eastern Hemlock (not the poisonous plant commonly known by the legend of the death of Socrates) is a large evergreen tree known for its economic, aesthetic, and ecosystem-related values. The tree is majestic, a staple on the east coast of the US and parts of Canada, and is the state tree of Pennsylvania. These giants can grow to be 160 feet tall with trunks that are 6 or 7 feet in diameter, as they grow slowly over a life that can be up to 1000 years long. But the hemlocks are in danger, and pretty soon there might not be any left.
Hemlock that has been infected by the hemlock woolly adelgid (Via United States Department of Agriculture).If you ever happen to find a hemlock tree while outside, look at its branches and the spaces between its leaves. Chances are you’ll probably see some odd looking white fuzzy blobs. These little white things are actually the ovisacs of an insect called the hemlock woolly adelgid, an invasive, aphid-like pest native to Japan which appeared in the US in the 1950s. Over the past six decades the hemlock woolly adelgid has slowly spread, and by 2005 had been reported in parts of 16 states up and down the east coast of the US.
When an eastern hemlock is infected, it usually takes about four to ten years before the insects completely overtake and kill the tree, however in some southern areas it can take only three to six years. These tiny creatures don’t look like much, but they’re slowly taking over, bringing down these huge, beautiful trees. When it was assessed in 2011, the eastern hemlock was listed as “near threatened” on the IUCN Red List, meaning the species is declining and approaching becoming endangered.
The trees are not well known or particularly exciting to most people (they don’t claim to be the king of the jungle, nor do they make loud roaring sounds), but they’re still incredibly important and deserve our attention. Everyone has heard about endangered rhinos or whales or other large, charismatic creatures, but very few know about the hemlock woolly adelgid’s killing off the hemlock trees, or the invasive emerald ash borer’s impacting the ash trees. Everyone knows about animals like the extinct dodo bird, but it’s a lot harder to find someone who knows about the recently extinct St. Helena olive.
Sometimes with all the exciting actions of animals around us, we forget about the plants. But we should remember how incredible these living organisms are; some grow to be far larger and live much longer than we ever will. There tends to be a bias towards animals over plants in protection efforts and studies, and among the general public we sometimes forget that environmental issues don’t just impact large animals, but all of the life on earth.
Plants are important too, in fact, we rely on plants in more ways than we realize or appreciate. Plants and specifically trees are foundations for entire ecosystems, and the loss of them impacts ecosystem structure and function. Eastern hemlocks are the homes to many rare species, and without the hemlocks, many species would lose their habitats. The loss of eastern hemlock individuals has already begun to affect transpiration, the loss of water from plant leaves, and as the water cycle changes slightly in these forests, many other organisms feel the effects. The loss of a few of these trees has a domino effect, causing harm to surrounding plants and animals; the hemlock woolly adelgid does not simply affect the trees but the whole ecosystem as well.
Just as we need to protect our large, well-known animal species, we also need to protect our endangered photosynthetic friends, the ones who are often forgotten, but on whom we all, big and small, rely.
By Aditya Nair
It’s a tale that seems as old as history. Those among us who have come very close to dying report extraordinarily vivid visions involving some combination of seeing the dead, passing through a tunnel, feeling dissociated from the body, and extreme emotional states among many other phenomena collectively referred to as near death experiences (NDE’s). These experiences tend to be relatively similar in nature from patient to patient in their general characteristics, and they are usually perceived with an extremely high degree of realism, leading many sufferers to describe them as life-defining experiences often tied to religious nirvana or enlightenment. A surprisingly large proportion of Americans report having had NDE’s- around 3%, a figure that represents 40-50% of all people who have come close to clinical death.
Despite the supernatural element of most NDE’s, many neuroscientists believe that NDE’s are largely explainable by current neuroscience in corporeal terms. Rather than being evidence for an afterlife or supernatural forces, NDE’s are more likely to be a hyper-realistic delusion brought about by abnormal patterns of neural firings from a loss of blood flow to certain parts of the brain as the body goes into emergency mode in the minutes and seconds right before death.
The first piece of evidence is the non-exclusivity of NDE’s to dying patients. It turns out that the conditions necessary for a NDE don’t necessarily involve imminent death, lending support to the notion that NDE’s are purely a result of abnormal brain chemistry. For example, one patient who lost consciousness due to low blood glucose levels reported experiencing an NDE upon waking up. In fact, a prospective study of NDE’s found that over half of NDE’s were experienced in non-imminently life threatening conditions.
Furthermore, many of the “classic” characteristics of an NDE can be experimentally demonstrated in studies that have little to do with death. For example, one commonly reported component of a NDE is an out of body experience, or OBE, in which the patient feels as if he or she is “floating” outside of their own bodies. Not being unique to NDE’s, OBE’s are experienced by people even during perfect physical and psychological health, sometimes as a common side effect of deep sleep. Neuroscientist Olaf Blanke showed that stimulation of the right temporopareital junction could elicit a strong OBE, demonstrating that disruption of sensory integration in that area could bring about the feeling of an OBE. It’s very possible that, when faced with physiological stress, sensory integration in this area is similarly disrupted, which results in the perception of an OBE just like in an experimental setting.
Many NDE patients also report that they travel through a characteristic “tunnel of light” during their NDE’s. However, this symptom too is well studied as a neurological phenomenon, usually in conjunction with lowered availability of blood in the retina. The sensation of passing through a tunnel of light is often reported in military airplane pilots, who are subjected to extremely strong forces that may drain blood from the head and eyes. The tunneling sensation is also often reported by glaucoma patients, who are victim to constricted blood vessels in the eye.
Although there are several other key characteristics of NDE’s that are also explainable scientifically, I have chosen for the sake of brevity to exclude them from this discussion. While some use the similarities across NDE’s to argue that NDE’s are the psychological manifestation of a human connection with “supernatural” forces, scientists respond that the consistency of NDE symptoms demonstrate that natural phenomena produce predictable physiological effects. Although the debate surrounding NDE’s will surely rage on in the theological and philosophical world, NDE’s are coming closer and closer to being entirely resolved as a scientific question.
By Tiago Palmisano
Edited by Bryce Harlan
It’s well known in the medical community that gut-bacteria produce beneficial effects. Commercials about probiotics – bacteria and yeast that provide benefits for human health– have become as prolific as prescription drug advertisements, and yogurts laced with specific strains of bacteria are now a fitness craze. Though generally thought to improve intestinal health, new research has shown that probiotics may also treat mental health diseases such as depression and autism.
Our intestinal tract contains more bacteria than our bodies contain cells. This diverse pool of prokaryotes makes its way into the intestines as soon as we are born, when we are exposed to the numerous organisms of the external world. Our relationship with bacteria persists throughout life, constantly involved in a delicate balance of chemical exchange. However, due to the location of bacteria in the digestive tract, the prescription of probiotics has been used mainly to treat conditions that affect the gut, such as diarrhea, ulcerative colitis, and intestinal inflammation.
Despite this, recent evidence has revealed how probiotics can also improve mental conditions, redefining the importance of gut-bacteria. In 2013, a Cal-Tech study concluded that mice whose intestines were injected with Bacteroides fragilis had reduced psychological symptoms of anxiety and depression. One possible mechanism for this profound effect is a chemical signal sent through the vagus nerve – a large nerve which connects the brain to organs such as the heart, lungs, and intestines. For example, one experiment found that ingestion of the bacterium Lactobacillus rhamnosus stimulates the vagus nerve in the gut of mice, changing the synthesis of receptors for the neurotransmitter -aminobutyric acid (GABA) in the brain, reducing anxiety.
Another way that probiotics may improve mental health is by reducing the leakage of the gastrointestinal (GI) tract. The GI tract is made up of the tubing from the mouth to large intestine. It absorbs nutrients from food for our bodies to metabolize. Certain conditions can make the lining of the GI tract leaky, resulting in the absorption of fewer nutrients. Injecting Bacteroides fragilis into mice with autistic symptoms reduces the leakiness of the GI tract, allowing essential nutrients to be absorbed that ameliorate some psychological symptoms of the autism.
Moreover, B. fragilis is not the only bacterium that has been shown to have beneficial effects for mental health. Another 2013 study demonstrated that in children with autistic symptoms, intestinal cultures had lower levels of certain bacterium genera such as Coprococcus, Prevotella and unclassified Veillonellaceae. Yet another study found that ingesting the strains Lactobacillus helveticus and Bifidobacterium longum improved symptoms of depression and stress in human volunteers.
This research is opening the door for a new wave of mental health treatments. A genetically modified bacterium strain that possesses multiple genes linked to mental health could be used as an alternative to artificially synthesized drugs. The potential for a natural organism that produces beneficial metabolites within the body itself is promising. Additionally, prescribing certain amounts of probiotic pills to patients would allow for easy regulation of these effects. However, research into the psychological abilities of probiotics – which doctors have appropriately dubbed “psychobiotics” – is still scarce.
On November 19th of 2014, researchers presented the new evidence for the link between gut-bacteria and the brain at the annual Society for Neuroscience meeting in a symposium called “Gut Microbes and the Brain: Paradigm Shift in Neuroscience.” Hopefully, this wave of recent findings will stimulate further research into the ability of bacterium to influence mental health. In the near future, advanced probiotics may be involved in treating intestinal, immune and psychological conditions, and one day a simple ingestion of bacterium-infused food may replace the abundant need for synthetic antidepressants or other psychiatric drugs. But until then, keep eating Greek yogurt – your brain may thank you later down the road.