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Dog persuasion exercise

Submitted by koganezova on Fri, 03/24/2017 - 15:04

We were presented with a scenario that went: A new retrovirus is killing domestic dogs at terrible speed, in a few months all domestic dogs are predicted to be extinct. However, scientists have developed enough vaccine to save one pregnant mother and her puppies: which breed dog should be saved?

My group and I concluded that the breed of dog that should be saved should be a member of the oldest breeds of dogs. One breed includes the husky, which has been around since the 19th century. We thought this because since they are one of the original breeds of dogs and have not been heavily selected for, so if they were to be regenerated, different dog breeds can be potentially brought back. 

Dr. Allan Detsky

Submitted by koganezova on Fri, 03/24/2017 - 12:33

Over the summer, I had the priviledge of working at NYU Medical Center and attending amazing conferences and talks. One day, a doctor named Allan Detsky came to talk at NYU Medical center. Physicians, residents, and students all came to listen to him. He held the most amazing talk that I have heard in a while. After the talk, I reached out to him saying thank you for his wise words and opinions. He got back to me almost right away saying it was an honor to give his input to future and current physicians. He then sent me a few of his other papers he has written that he thought I would enjoy. One was a paper written to educate future students and residents on how to go through your years while learning and interacting with patients from the eyes of current students, residents, and physicians. One resident told his story about how he met a patient that was in his last stages of HIV. He did not have much time left when the resident met him, but the resident continued to be by his side every single day. Even with the chaotic hours the resident had, he would stop by to take a break in the patients room. He did this for two years until the patient passed away. Although it was heartbreaking, the family thanking him and showing their gratitude made the pain go away for the resident and it solidified even more why he was in this profession. This is one of the most important aspects of healthcare, passion and dedication.

Knee jerk reflex perfect paragraph

Submitted by koganezova on Fri, 03/24/2017 - 12:23

The muscle stretch reflex is an automatic response our skeletal muscle goes through when it is stretched. Once the skeletal muscle is stretched, there is a reflex that wants to bring the muscle back to contraction. This is thought to hold a protective purpose. This is how the knee jerk reflex comes in. When the doctor hits your knee with the hammer, he hits your tendon which in turn causes your thigh muscle to stretch a little bit. Shown through the muscle stretch reflex, once that thigh muscle stretches even a little, the reflex causes the muscle to contract which in turn kicks your leg up. 

Sleep and dementia

Submitted by koganezova on Fri, 03/24/2017 - 01:14

I receive weekly updates on the recent new findings in the medical world and came across one today that was extremely intriguing. New studies have shown that longer sleep has a correlation to a higher risk of getting dementia. The team found that people who sleep 9 or more hours consistently are twice as likely to get dementia within the next ten years. They also found that people who sleep longer, have a smaller brain volume and are not able to retain as much information as those who consistently sleep less than 9 hours. It makes that longer sleep has all these risks neurologically speaking, because we do not use our brains for such a long period of time. Good thing being a premed student, I don't get as much sleep.

Worm-like creature transformation

Submitted by koganezova on Mon, 03/20/2017 - 23:34

Before spring break, my worm looking creature that was given the beginning of the semester was in a coccoon for about 2 weeks. Slowly, parts of the coccoon were breaking apart. When I got back yesterday, I noticed that the coccoon was completely dismantled and my worm looking creature looked nothing like a worm anymore; it had transformed into a moth. Shortly after I noticed it was desperately trying to get out of the container it was in, so I let it fly away outside. Safe travels to the non-worm looking creature.

Knee jerk reflex

Submitted by koganezova on Tue, 03/14/2017 - 13:16

This spring break, I am studying for the MCAT exam I will be taking this coming May. In the midst of my studies yesterday, I came across an extremely interesting mechanism. When we go to the doctors office for our annual check up, the doctor hits our knee with a platic hammer. Almost always, if the doctor hits the correct area of the knee, our leg jerks up as an automatic response. This is known as the knee jerk reflex, which comes from another mechanism called the muscle stretch reflex.

The muscle stretch reflex is an automatic response our skeletal muscle goes through when it is stretched. Once the skeletal muscle is stretched, there is a reflex that wants to bring the muscle back to contraction. This is thought to hold a protective purpose. This is how the knee jerk reflex comes in. When the doctor hits your knee with the hammer, he hits your tendon which in turn causes your thigh muscle to stretch a little bit. Shown through the muscle strecth reflex, once that thigh muscle stretches even a little, the reflex causes the muscle to contract which in turn kicks your leg up. 

There are two parts to the reflex: the afferent and the efferent parts. The afferent part of the reflex is the stimulus, the feeling of the tendon getting hit. Muscle spindle that are located in your thigh detect the stretch of the muscle. Somatosensory neurons get information from those muscle spindles, which then make an excitatory synapse with another neuron that are afferent and go to the spinal cord. The efferent part of the reflex is the response, the leg kick. Lower motor neurons are neurons that make synapses with skeletal muscle. These lower motor neurons make a synapse with the somatosensory neurons and receive a signal that goes all the way down their axon and makes a synapse with the skeletal muscle, in this case the thigh muscle which in turn produces the leg kick. The most interesting part of this whole process is that it does not involve the brain at all, only the spinal cord.

Retina experiment PP

Submitted by koganezova on Thu, 03/09/2017 - 14:33

For my neurobiology class, an assignment of ours was to read an article about an experiment that was testing to see whether vision could be restored safely in a damaged retina. The experiment looked at three systems: blind mice, macaque, and humans. The most interesting experiment they did with mice in my opinion was the light/dark box. First they started off by treating the blind rd1 mice retinal ganglion cells with red-activatable ChR (ReaChR) by using an AAV vector. After this was done, there were three groups that the experimentors were looking at: ReaChr-treated rd1 blind mice, untreated rd1 blind mice, and wild type mice. They put these three different mice groups in a light box at different times and observed how much time each one was spending in that box and what kind of behaviors they were exhibiting. They found that the treated rd1 blind mice were spending the least amount of time in the light box compared to the wild type mice and the untreated rd1 blind mice. This was because of the lack of adaptation for light ReaChR produced. Unlike us, that can adapt to bright light to refrain from the strain lights at high wavelengths have on our eyes, these treated mice had nonstop straining to their eyes, which most likely resulted in their short amount of time in the light box.

Experiments done on the retina

Submitted by koganezova on Thu, 03/09/2017 - 14:30

For my neurobiology class, an assignment of ours was to read an article about an experiment that was testing to see whether vision could be restored safely in a damaged retina. The article is called "Red-shifted channelrhodopsin stimulation restores light responses in blind mice, macaque retina, and human retina". The researchers performed several experiments to test this.

A major drawback in targeting microbial opsins, such as channelrhodopsin-2, is that ChR2 requires stimulation with blue light at high intensities, which have a high risk of inducing photochemical damage in the retina. A solution to this problem is the usage of red or orange-shifted channelrhodopsin variants. 

The experiment looked at three systems: blind mice, macaque, and humans. They used mice to do the parts of the experiments they could not ethically do on humans. The most interesting experiment they did with mice in my opinion was the light/dark box. First they started off by treating the blind rd1 mice retinal ganglion cells with red-activatable ChR (ReaChR) by using an AAV vector. After this was done, there were three groups that the experimentors were looking at: ReaChr-treated rd1 blind mice, untreated rd1 blind mice, and wild type mice. They put these three different mice groups in a light box at different times and observed how much time each one was spending in that box and what kind of behaviors they were exhibiting. They found that the treated rd1 blind mice were spending the least amount of time in the light box compared to the wild type mice and the untreated rd1 blind mice. This was because of the lack of adaptation for light ReaChR produced. Unlike us, that can adapt to bright light to refrain from the strain lights at high wavelengths have on our eyes, these treated mice had nonstop straining to their eyes, which most likely resulted in their short amount of time in the light box.

Pheromones PP

Submitted by koganezova on Fri, 03/03/2017 - 11:24

Pheromones are substances that are secreted outside by an individual, mostly from sweat in humans, and received by another individual. I learned about pheromones in my Neurobiology class, but I never realized they had something to do with developmental processes as well. Girls tend to start puberty around the age of 11-13 on average. It has been shown through studies that a girl living with a stepfather has a higher chance of starting puberty much earlier than average because of pheromones that the stepfather secretes. The reason girls start at an average age is because the pheromones their own fathers secrete are biologically the same chemicals. But because of the difference in biological chemicals in stepfathers, the girls hormones respond in a way that brings earlier maturation.

 
 

Pheromones

Submitted by koganezova on Thu, 03/02/2017 - 21:05

Pheromones are substances that are secreted outside by an individual, mostly from sweat in humans, and received by another individual. Just recently I read a paper about how pheromones affect womens mood and sexuality. Secretion of pheromones result in a better mood in women and more focus in attention. In animals similarly, pheromone secretions are used by females to determine who they should mate with.  

Interestingly enough, I learned about pheromones in my adolescent psychology class as well, but in a different aspect. Girls tend to start puberty around the age of 11-13 on average. It has been shown through studies that a girl living with a stepfather has a higher chance of starting puberty much earlier than average because of pheromones that the stepfather secretes. The reason girls start at an average age is because the pheromones their fathers secrete are biologically the same chemicals. But because of the difference in biological chemicals, the girls hormones respond in a way that brings earlier maturation.

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