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https://eandt.theiet.org/content/articles/2019/04/also-i-hope-we-can-cure-all-disease-interview-with-neurotechnologist-ed-boyden/

This article, published on April 3, 2019, is about Ed Boyden, the founder of optogenetics. This article interests me because I work in a lab on campus in which we use optogenetics. Recognizing that the brain’s neurons communicate using electrical pulses, Ed Boyden wanted to invent a technique to further define the neural circuits in the brain. The technique uses proteins called opsins from natural sources such as bacteria and fungi, that are light-gated ion channels. A neuron is made to expresses these opsins using injection on a viral vector, so when a light is shined on the neuron, it is depolarized and fires action potentials. This technique relates to material in this course because it can be used to further elucidate the neural circuits involved in pretty much everything. For example, in my lab, we are using optogenetics to find the neural circuits involved in sensorimotor gating, something that patients with schizophrenia have an inability to do. If we can find the circuit, we will be better able to design treatments for patients with schizophrenia. In order to further the technique of optogenetics, less invasive applications would be ideal, although these do not exist yet. As Ed Boyden mentions, we need better methods to watch the brain in action. The only way we can do this in the lab right now is by decapitating the mice and harvesting their brains.

The three phases of digestion are cephalic, gastric, and intestinal. During the cephalic phase, food has not entered the body but smell and thought of food stimulates the central nervous system to start preparing the body for the injestion of food. The salivatory glands begin to salivate. During the gastric phase, food begins to enter the stomach and there is a strech in the stomach that triggers hormonal and neural signals. Mechanical and chemical digestion begin to take place in the stomach. An increased pH stimulates G cells to release gastrin, which stimulates stomach activity. The intestinal phase begins when food passes through the pyloric sphincter and into the small intestine. There is mechanical, endocrine, and neural control. 

In this lab the starting materials (acetic acid and isopentyl alcohol) were reacted together. The refluxed solution never separated into two layers so the expected final product of isopentyl acetate was not found therefore there was no final weight or percent yield calculated. This could have been due to either a failure to mix the liquids well or from a frayed plastic connector piece in the distillation apparatus. In order to analyze the odor and IR spectroscopy another student’s product was used. The odor resembled a banana scent which is comparable to the expected odor of isopentyl acetate. The IR spectrum has a large dip around 1740cm^-1 confirming the presence of an ester. However, there is also a large peak at about 3600cm^-1 indicating some impurities in the product.

Bulimia Nervosa, commonly known as Binge-Eating Disorder is a mental disorder in one which a person binges followed by behaviors designed to prevent weight gain from the binges. A binge is classified as uncontrolled eating of large amounts of food. Some behaviors include self-induced vomiting, abuse of laxatives (or other purging medications), fasting, and excessive exercise. Like anorexia nervosa, about 90-95% of bulimia cases occur in females. The peak age of onset is between 15-21 years old and the symptoms can last for several years.

Bacteriophages also have another type of life cycle. It is called the lytic cycle, the purpose of this life cycle is to rapidly replicate, lyse the cell, then package it’s DNA to go to a bacteria and infect another one. The lytic cycle has the bacteriophage replicate it’s DNA rapidly while making packaging for that DNA. The packaging includes the head and tail of the bacteriophage, this will keep the DNA safe until it gets to the next bacteria that it will infect. It also has to package it in a way that the bacteriophage will be able to insert its DNA into the next bacterial cell that it infects. This is a very interesting process. The goal of this process is to make as many bacteriophages as possible, this will allow the bacteriophages to leave the host cell and infect a bunch of other host cells. There are many proteins that the bacteriophage carry with them to make packaging for their DNA. And like in the lysogenic life cycle some bacteriophage use the host proteins to create their own packaging. Bacteriophages really are interesting, they infect bacteria which can infect us. There are viruses for everything, they can infect everything in life. The only thing that can’t be infected by a virus is a virus itself, and that is only because they can’t replicate on their own.

Chemical transformation of E. Coli cells is the process by which bacterial cell asre made to take up desired plasmids. Chemical transformation is performed after TOPO cloning. Some preparatory steps include equilibrating the water bath to 42⁰C, warming selective plates at 72⁰C for 30 minutes and thawing vials of One Shot Top 10 E.Coli cells on ice. To start off, 2 microliters of TOPO cloning reaction products are added into vials, mixed gently and then incubated on ice for 5-30 minutes. The cells are heat shocked for 30 second at 42⁰C without shaking before being placed on ice for 2 minutes. 250 microliters of S.O.C. medium is added, the tube is capped tightly and then shook horizontally at 200RPM and 37⁰C for 1 hour. 

Bacteriophages might be one of the coolest things in all of the natural world. They are viruses that infect bacteria. Bacteriophages are the pictures you see that look like an alien spaceship landing on a cell surface. They send their DNA into the bacterial cell. They can go through 2 separate life cycles, lytic and lysogenic. The lysogenic life cycle of the bacteriophage is for replicating DNA as fast as possible within the cell. What this means is that the bacteriophage replicates it’s own genome within the host cell replication machinery. Other types of bacteriophages package their own replication machinery so they don’t have to borrow it from the host cell. I think that packaging their own replication machinery is significantly less common than borrowing it from the host cell. It is more efficient for the bacteriophage to borrow the replication machinery from the host because it doesn’t have to waste space carrying it to the next host cell if it is already there. Typically during the lysogenic cycle DNA from the bacteriophage is inserted in to the bacterial genome. This is sometimes how genes are passed from bacteria accidentally. It is a really interesting process and sometimes drug resistance accidentally gets passed from bacteria to bacteria.

This disease known as the African sleeping sickness seems to affect a majority of sub-Saharan African countries. Tsetse flies are the main cause of this transmission of infection to individuals living within these countries. I thought it was interesting that these flies only inhabit tropical Africa and are large biting parasites that live by feeding on the blood of animals. The blood of the animals is where initially the flies themselves are infected. I also think that because of the scarce and in availability to the treatment of this disease is how the spread of the disease continues to infect so many individuals. There has been a reduced number of new cases since 2009 which used to be 10,000, meaning that the research and discovery of treatments and medications is helping the countries infected. The goal of this renovated medication is to stop the disease at an earlier stage and prevent the widespread of infection. Because the disease can be fatal, I think that with an earlier treatment could help prevent the loss of many human lives as well.  

Oviposition preferences of the female azuki bean weevil determine the success of the offspring. The choice of the female determines the food source for the larvae, and because the bean on which it was laid will be the only food source for its entire development, the right decision on the female's part is crucial. After pupation, the beetle does not consume food or water and will seek to reproduce. In experiments that test for preferences, it is found that the azuki bean weevil has a high preference for the cowpea legume out of five beans- cowpea, mung bean, azuki bean, kidney bean, and soybean. The number of eggs per cowpea when the female was given a choice revealed roughly 6 eggs per female on the cowpea, and zero eggs per female on the kidney bean. Furthermore, the developmental time and the rate of adult emergence was reduced for the eggs laid on cowpeas, suggesting that the choice was beneficial to offspring. Further research on other species suggests that certain legumes produce a higher concentration of phenol, found to be toxic to certain species, thus leading to avoidance on those legumes.