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What comes to mind when you hear the term “gene editing”? Something out of a science-fiction movie, a dimly lit laboratory with scientists in white coats moving smoky liquids around, injecting patients with questionable fluids, a mutated outcome that no one expected? Gene editing has been popularized in movies like Gattaca and Splice, painting a portrait of gene editing as something sinister, something that can change everything about a person and that can spiral out of control.

Our blood is a bountiful source of information that cancer researchers and clinicians have been tapping into for over a century. For instance, many cancer biomarkers can be found in blood and are useful in making clinical decisions. For this article, I’m going to narrow in on an exciting and relatively new cancer biomarker: circulating tumour DNA.

When it comes to applying electrodynamics to advance our understanding of physiology, the brain ranks among the most common applications. This doesn’t come as much of a surprise; the brain is a dense collection of neurons which fire electrical signals (action potentials) to communicate with other downstream neurons or tissues. The regulation of the volume and rhythm of firing is responsible for how we move, how we speak, and how we breathe. The dysfunction of firing, occurring through various mechanisms, is the cause of many neurological disorders, especially those defined by motion and sensory abnormalities. Take for example multiple sclerosis, a disorder characterized by the loss of myelin around neurons in the central nervous system, resulting in weakened neuronal activity and motor dysfunction [1]. Clearly, the regulated firing in populations of neurons can be viewed as a potential end-goal in clinical neuroscience, but how do we go about arriving at this desired outcome?

First off, let’s start with a single decision tree before we jump into a forest. Decision trees are predictive models that can be used for both classification problems to evaluate discrete classes such as cat or dog and regression problems to evaluate continuous variables such as age. Decision trees are also known as CART (Classification and Regression Trees). You can look at a decision tree as asking a bunch of questions until you arrive at the answer you are looking for.

Last month, I wrote a post called How your cells stop cancer before it starts, which focused on the fact that, despite us being exposed to DNA-damaging events pretty much all the time, we are not all walking bags of cancer. I then touched on a few reasons why this is the case, including some self-correcting and protective cellular mechanisms that keep track of our DNA; the fact that you need several mutations, in just the right places, to start a cancer growing; and that when cells do start to accumulate potentially dangerous DNA damage events, they are sometimes seen and eliminated by your immune system, which can kill a potential tumour before it gains a foothold.

When fellow GSD blogger and music-lover, Sayan Nag, proposed a blog series covering the neuroscience of music, I readily jumped on-board. For us, and the many in the world like us, music is an integral part of day-to-day life. Drawing from countless hours of staying plugged into my earphones or indulging in whatever tunes creep up in my mind, I know that music has a profound impact on my mental state, being able to singularly alter my mood and overall outlook. Together, Sayan and I will delve deeper into the neuroscience behind common musical experiences. Given the on-going political and social unrest – support the cause! – unfolding over the backdrop of a global pandemic and climate change, we’ve decided to take a look at how music can help ease the toll that stress takes on our body.

If someone you know has ever been diagnosed with cancer, they likely received a treatment known as chemotherapy, or “chemo”, which is the use of drugs to kill cancer cells or stop them from growing [1]. Depending on the person’s individual cancer, chemotherapy could be given alone or in combination with surgery and/or radiation. Some early-stage cancers may not even need chemotherapy at all! But what exactly is chemotherapy, and how does it work?

When considering the sheer complexity of the brain, an interesting quote by Emerson Pugh always comes to mind: “If the human brain were so simple that we could understand it, we would be so simple that we couldn’t.”

Fluorophores have long enabled biologists to localize and quantify features present in a given sample. Proteins and dyes capable of fluorescence can be used to stain targets in a sample or introduced into your sample’s genome and colocalized with a target protein as a marker of that protein’s expression. Targets that are selected for analysis with fluorescent molecules are not always perfectly flat and 3d information can be useful in determining the function of the target that a fluorophore labels. Two-photon fluorescent microscopy takes advantage of a reduction in scattering of light in the infrared range in tissue to view fluorophores beneath the surface of a sample.

Your DNA, at least in part, makes you who you are. DNA encodes genes, genes encode proteins, and proteins allow your cells to do their jobs. If anything breaks – if your DNA gets damaged and an essential gene mutates, for instance – the cell can die. Or, often worse, the cell can live, and continue to divide. It can accumulate more mutations, a rolling ball that can culminate in the growth of a tumour. With the risk of cancer in the mix, you might think that cells would pull out all the stops, avoiding any kind of DNA damage at all costs. But increasingly, research is suggesting that DNA damage is just a part of life. Your cells experience tens of thousands of DNA lesions every single day, but for the most part…everything is fine [1].

Every cell in our body contains the same DNA sequence. So, if the order of the nucleotides is the same, how does cell specialization arise? The answer lies in how the DNA is folded in a cell, exposing certain regions for expression while repressing others. Following discoveries of chromosomes in 1879 by Fleming, Thomas Hunt Morgan’s establishment of chromosomes harboring the developmental program in Drosophila and identification of DNA as the primary carrier of genetic information (see this blog post), many researchers sought to investigate the concept of genetics. In 1930, H.J. Muller provided evidence of heritable changes in phenotype without any changes in genes [2]. This along with observations of the divergence of cell phenotypes and the subsequent maintenance over dividing cells indicate that there are inheritable changes in gene expression independent from alternation of the DNA sequence termed “epigenetics”.

Much has changed since the early days of MRI, when the pioneers of the field – among them, Raymond Damadian, Paul Lauterbur, and Peter Mansfield – first grappled with the inherent speed bottleneck of MR imaging. Modern MRI has benefited from the accumulation of technological advances and ingenious imaging strategies developed over the past 4 decades. MRI researchers continue to push for faster image acquisitions, attempting to strike a tricky balance between improving scan time efficiency and preserving image quality.

Do you ever wake up and have your morning coffee and suddenly ponder why you may be tired? It’s likely that the cup of coffee you had won’t make up for the that fact that you had less sleep than the recommended seven hours a night for people aged 18-65 years old. At first glance, a few nights without a lot of sleep may not seem overly detrimental to your overall health, but it can definitely become a larger issue when you chronically lack sleep or if you have insomnia or other sleep disorders such as sleep apnea where your breathing starts and stops at night.

Here is a terrifying statistic: Cancer is one of the top leading causes of death, globally. To put that into perspective, 1 in 6 deaths around the world is because of cancer (1). By definition, it is a large group of diseases that can start in almost any organ or tissue in the body when cells start to grow uncontrollably (1). The burden that cancer brings to the healthcare system, the community, families, and individuals is massive. Financially, economically, physically, and emotionally, cancer is a constant battle that we continue to fight every single day. It is a battle where patients, families, healthcare workers, researchers, and many more come together with the hopes of a common outcome: to cure it.

This is something every high school biology student knows: Genes are the building blocks of life, and genes are encoded in DNA. Nowadays, this is an unquestionable fact, but actually, we didn’t know that DNA was so important for life until 1944 [1]. That’s less than a hundred years ago. That’s at the tail end of the Second World War – which means that every single person fighting in the First World War did not know what we now know, that genes are made of DNA.