Reflection

As this is the last week of class, I felt it was appropriate to write a blog reflecting what I learned in this class. Overall, I feel like I have become much more efficient concerning microscope work and I feel confident enough to even help other people. I must also say that I have learned to pay attention to detail. Before this class, when I bought the book, I peeked through and thought all the cells looked the same. Today, I did the exact same thing, but I can now tell the difference between the shape and size of cells. I am also able to recognize cells by their shape and categorize them into different tissue systems. For example, fibroblasts have a teardrop shape and are part of connective tissue, while Purkinje cells are slightly more elongated and belong to cardiovascular tissue. I am surprised by how much I liked this class and how much I have learned. Hopefully, I am able to prove that on the upcoming final. : )

Asperger Syndrome

I was talking with a friend this week about Asperger Syndrome, and she peaked my interest in the cause of the disease. The main cause of the disease is linked to neural activity, although genetics may also play a part. In Asperger patients, there is an abnormal migration of embryonic cells during fetal development that affects brain structure. This, in turn, affects the neural circuits that control thought and behavior. The genetic component of this disease has not yet been linked to a specific gene, however scientists have determined that the disease runs in families. Asperger patients are usually identified by their lack of judgment, unusual facial expressions and repetitive behavior. Overall, they are most affected socially, although adults can lead relatively independent lives. I immediately thought about the chapter in our textbook about nerve tissue and how something as small as a thinning myelin sheath on an axon can have disastrous effects on an individual. As proved by this disease, even neurological abnormalities during fetal development can have lifelong effects.


The information above was taken from the following reference: 
"Asperger Syndrome Fact Sheet." National Institute of Neurological Disorders and Stroke. National Institutes of Health, 4 Nov. 2011. Web. 30 Nov. 2011. <http://www.ninds.nih.gov/disorders/asperger/detail_asperger.htm>.

Fordyce Spots

This week in class, we were talking about the first part of digestion. One term that was new to me was Fordyce spots. These are modified sebaceous glands that are not associated with hair follicles, and yet, are found in the submucosa just lateral to the corner of the mouth and in the cheeks opposite the molar teeth. This was a new term to me because I assumed that all sebaceous glands were equal. It was new for me, not only to learn that these are really sebaceous glands, but also that these spots are visible to the eye. It's interesting that these are visible when they are found in the submucosa layer.

Reflections

This picture is taken from the following website:
http://imageshack.us/f/73/reflection1by9.jpg/

So we had our third exam today, and I must say I felt more confident on previous exams. This is good because I'm not only learning new subject material, but I'm able to teach myself a new way to learn material. Last week, I commented on how I thought exams and quizzes were my weakest point, but this week, I had a big change of heart. I spread out my studying time instead of studying for multiple hours at once. For some reason, it made a huge difference and I was able to retain the information for longer, in almost as much detail as I studied it in. Although I still think this area is my weakest area in this class, I feel like I have gotten much stronger in it. The other point that I was commenting on in my last post was about how I needed to make labs more fun for everyone. I am happy to report that we have formed a good group at the back right of the classroom. We have all finally gotten comfortable with each other enough to have fun while we complete our work. The funny thing is that none of us really knew each other before this class, and now we've all become friends. I always thought of myself as a shy person and I usually don't strike up conversations with everyone I meet, but for some reason, I've been able to come out of my shell in this class and accomplish my goal of making some noise in class.  : )

Reflection

Overall, I have come to enjoy Histology class. At the beginning of the class, I have to admit that I was skeptical about the interest I would have doing microscope work for 16 week straight. Now, however, I am at ease using the microscope. It seems like second nature. Even while doing drawings during lab, I feel as though I am more perceptive about the little details (that actually matter in this class). I find myself looking for them, and identifying other layers and structures in lab to help myself remember what they are (i. e. blood vessels or connective tissue) and how they look in different tissues. The hardest part of this class for me are still quizzes and exams. I'm not sure if I freeze up or if I just need more practice identifying specific tissue characteristics. Hopefully, this is something that will be fixed in the near future, especially as the end of the semester is drawing near. The only thing I really feel like I need to work on is talking. Our labs are still extremely quiet, and I just need to step up and make them more fun for everyone. : )

Vertigo

This picture was taken from the following website:
http://wpcontent.answcdn.com/wikipedia/commons/0/0a/VestibularSystem.gif

My mom loves to tell me stories about when I was baby, and I, in turn, love listening to them. I was born prematurely, and the doctors at the time diagnosed me with quite a few conditions. One of those conditions was vertigo. Naturally, my interest was peaked and I knew I would be able to find a correlation with histology. All I previously knew about vertigo was that it caused uncontrollable imbalance in a person, which is caused by the ear, the organ responsible for balance. The condition affects some individuals more than others. Some adults cannot get out of bed on a bad day, while it affects others only at certain times. For example, I cannot stand straight when I'm praying. Whether I'm standing up or kneeling down, when my eyes are closed, I lose control of my balance. I usually sway and lightly knock into the people on either side of me. Chapter 25 of our textbook focuses on the ear, and one clinical correlation described is vertigo. It is described as "the sensation of rotation without equilibrium" and "signifies dysfunction of the vestibular system." Causes include viral infections, drugs and tumors such as acoustic neuroma. These neuromas develope near the internal acoustic meatus and exert pressure on the vestibular part of cranial nerve VIII. Vertigo can be stimulated in normal adults with excessive stimulation of the semicircular ducts. Excessive stimulation of the utricle can also produce motion sickness in some adults.


In essence, this describes how vertigo can arise in an individual -- through manipulation of the internal ear. The relation to the cranial nerve was a reminder of how all our body systems work together to produce an overall effect. While we cannot necessarily prevent vertigo from occurring, we now know why it is caused.


The information above was sourced from: Ross, Michael H., and Wojciech Pawlina. "Ear." Histology: A Text and Atlas: With Correlated Cell and Molecular Biology. 6th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health, 2011. 937. Print.

Factor VIII

This picture was taken from the following source:
http://themedicalbiochemistrypage.org/images/coagulationcascade.jpg

Just today in biochemistry class, we were discussing proteolytic cleavage in the process of blood clotting. Hemophilia came into the discussion and our teacher explained to us how clotting factor VIII is to blame. A deficiency in factor VIII causes hemophilia A, which is the most common type of hemophilia. In class, we were focusing on the cascading pathway that causes blood clotting. Factor VIII is a simple accessory in this pathway, yet its deficiency causes a life-threatening disease. In the diagram above, this is especially apparent. My attention was, once again, brought to the fact that something always affects something else, at least in the body. In there is one deficiency, it is expressed in another pathway. This reminded me of different diseases that occur within the cardiovascular system, since this is what we were studying most recently in histology. The difference between an active and inactive enzyme can be the difference between a disease and "normality". The textbook describes "prothrombogenic agents" as the "agents that promote thrombi formation." These agents simply fail to function in hemophiliacs. It was nice to be able to find a link between histology and one of my other classes. The things we learn relate to one another, but it's nice to be able to identify that in such a direct way.


The information above was taken from the following source: Ross, Michael H., and Wojciech Pawlina. "Cardiovascular System." Histology: A Text and Atlas: With Correlated Cell and Molecular Biology. 6th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health, 2011. 409. Print.

Reflection

This picture was taken from the following website:
http://library.creativecow.net/articles/okerstrom_jon/reflections/OddReflection1.jpg

As we have mid-terms this week, I thought it would be a good week to do a reflection blog. I enjoy this class a lot. At the beginning of class, I wasn't sure how much I would enjoy it. Now that we are discussing body systems, I am having a lot of fun. It's almost like re-taking College Biology, but with all the details you wanted to have, even though you couldn't really handle them at the time. I guess we had to get through all the basic (i. e. boring) information before we could get to the more complicated (i. e. fun) material. The same experience occurred with the labs. I wasn't sure how much interaction I could handle with microscopes, but it has become fun over the past two months. It's fun to see how long it takes me to focus on a slide, and the process definitely gets easier over time. I wish the labs were more interactive simply because I feel like we still have not bonded as a class. We are all very quiet, and although we sort of know each other now, we still aren't as comfortable as we should be with one another. My favorite thing about this class is that studying comes naturally because of the work that we do in class (with concept maps and discussions) and labs (with all the figures we draw). My least favorite thing is classmate interaction, or lack thereof, but that is definitely something that can be worked on in the future. I just have to take the first step. : )

Myelination

This picture was taken from the following website:
http://neuromuscular.wustl.edu/pics/diagrams/functional/myelinst.jpg

We have been talking about the nervous system this week in class and there were some terms that I encountered in the textbook that I was previously unfamiliar with. The first term is "abaxonal plasma membrane." While this sounds complicated, it is easily described as "one domain that consists of the part of the Schwann ell membrane that is exposed to the external environment, or in our terms, the endoneurium." Two other terms followed in the text, both of which I was unfamiliar with also. The next term goes along with the first and is "adaxonal plasma membrane," which is defined as "the other domain which is in direct contact with the axon." The last term that goes along with these two is "mesaxon." This is "the third domain and is created when the axon is completely enclosed by the Schwann cell membrane." This is also the most complex membrane in that it is "a double membrane that connects the abaxonal and adaxonal membranes and encloses the narrow extracellular space." These terms came up in class because of the myelination process that begins when a Schwann cell surrounds the axon. The easiest way for me to remember these terms is by thinking about the body's anatomy and remembering abduction and adduction. Also, thinking about the endoneurium and epineurium will help me keep the two terms straight.


The information above was taken from the following source: Ross, Michael H., and Wojciech Pawlina. "Nerve Tissue." Histology: A Text and Atlas: With Correlated Cell and Molecular Biology. 6th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health, 2011. 365. Print.

Lethal Injections

The picture above was taken from the following website:
http://www.yaare.com/wp-content/themes/gazette/2010/01/What-is-Lethal-injection.jpg

Recently in the news, a story broke about long-time prisoner Troy Davis who was executed through lethal injection. This story caught my interest, not due to the legal aspect, but to the scientific aspect. It brought to my attention the fact that I do not understand how lethal injections work. After all, with our powerful bodies, how can one simple injection kill us?


After doing some simple research, I found out that "death by lethal injection" should actually be called "death by three lethal injections." It is important to note that each injection contains lethal amounts of powerful drugs, so as to ensure the death of the intended victim. First, an anesthetic called sodium thiopental depresses the activity of the central nervous system. As we have recently learned, without a properly functioning CNS, body functions are decreased greatly. Specifically, this drug increases the effect of GABA, a neurotransmitter that has an inhibitory effect of brain activity. 


Following a saline flush, which is used to push the drug to enter the bloodstream faster, the second drug is administered. This time, the injection consists of a high dose of pancuronium bromide. This drug acts as a neuromuscular blocker, preventing the neurotransmitter acetylcholine from communicating with muscles. This loss of function from ACh stops all muscle function and leads to paralysis. This, in turn, leads to the end of breathing because the diaphragm muscle is no longer able to contract and expand.


After another saline flush, the third injection can be administered. This is the substance we usually think of as lethal -- potassium chloride. This drug attacks the heart with charged particles that interrupt the hearts' electrical signaling. The most interesting piece of information -- the entire process usually takes less than ten minutes! It's so hard for me to believe that a person can be put to death by lethal injection in less than a quarter of an hour. 


Researchers have become interested in post-mortem reports of prisoners who have died by lethal injection because the concentrations of the three drugs used get quickly absorbed into fat and muscle tissue, even after death. Some claim that an excess concentration of drugs are necessary for injection into the bloodstream to ensure the prisoner does not survive through the process.


Each part of the lethal injection process directly relates to the nervous system we are discussing in class, thus it made my investigation very interesting. We have briefly discussed GABA, Ach and other neurotransmitters. Researching this topic, however, has helped me understand truly how quickly those neurotransmitters work.

The information above was sourced from: http://scienceline.org/2007/11/ask-sergo-deathpenalty/

Craniopagus Twins

This picture was taken from the following website:
http://baylorlariat.com/files/2011/09/britain-twins_jams1-ftw.jpg

This picture was taken from the following website:
http://baylorlariat.com/files/2011/09/britain-twins_jams-ftw2.jpg

My dad has a rule that we have to watch, and sometimes even listen to, the news. Thus, I get very excited when I can actually relate to something that I hear and/or watch. This week, Yahoo News broke a story about the successful separation of conjoined twin girls from Sudan - Rital and Ritag. This interested me because, for the past year, these girls were craniopagus, meaning they were joined at the head. The story also stated they were using more of one girl's heart. It was simply amazing to me that these girls had shared blood flow in the brain, and yet, doctors were able to separate them successfully. The first picture above shows the girls before their surgery, while the second picture shows the babies after their surgery. I love pediatrics, so this story caught my attention initially, however, I also work with lots of transplant babies, some of whom do not survive. Thus, it is very uplifting to hear about success stores. Overall, this story opened my eyes to how wonderfully God created us. While these twins may have been deemed unfortunate in the past, their separation will serve as one of the biggest success stories in the surgical world due to the kindness of a British charity. The cells, tissues, and even the organs these girls once shared have now been separated in such a way that each of them is able to benefit through the use of their own bodies. God created us so that our bodies can function specifically for our needs -- a truly wonderful thought.

House

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http://nynjbengali.com/wp-content/uploads/2009/04/gregory-house-md.jpg

This past Sunday, September 11th, I watched an episode of "House." The episode was entitled "Sleeping Dogs Lie" and the original air date was April 18, 2006. Although it was an old episode, I found a startling connection with histology. 


The episode was about a lesbian couple, where one partner, Hannah, was deathly ill. She ends up at the hospital where House and his team work to cure her. She had various symptoms, one of which was insomnia. She was unable to sleep for almost ten days. This symptom put an extra rush on the doctors, though, because the human brain can only function for a maximum for ten days without sleep (or so they said on the show). Eventually, Hannah got worse and started bleeding. The blood sample, however, indicated the presence of nasal epithelia. Here's the link to histology. This wouldn't have been a startling connection with histology if the blood had come from her nose. She was, however, having rectal bleeding, which brings great surprise as to why nasal epithelia could be found here. The rest of the episode was filled with yet more drama, which is no surprise for this show, and eventually ended with Hannah needing a liver transplant. Being the ever loving and faithful partner, Max, the other partner in the relationship, donated half her liver to keep Hannah alive. Yet another "House" episode had a happy ending.


So...back to the histology connection presented. The rectal blood contained nasal epithelial cells, simply explaining that the blood came from the nose. This is logical because the patient developed a nose bleed before she was given a blood transfusion. The striking feature in all this to me was not the fact that nasal epithelial cells were found in the rectal blood, but rather, the fact that they were able to detect the presence of the nasal epithelial cells in her blood. This would, clearly, be an unlikely place to look for these cells. It occurred to me, however, after our many discussions in class, just how specialized this epithelium truly is and how creatively we were designed. As much room as there is for blood to move around in our bodies, each type of cell was specially and uniquely designed to fulfill an exact purpose. In this case, ciliated epithelium is suspected to be found in the nasal passages because the cilia help sweep out foreign substances from the beginning of the respiratory tract. Watching this episode was just a great reminder that something as simple as epithelium can teach us so much.

Desmosomal Attachment Plaque

The picture above shows the desmosomal attachment plaque and highlights the placement of the desmoplakins and plakoglobins.


This week in Histology class, we discussed epithelial tissue. One of the terms I was unfamiliar with was "desmosomal attachment plaque." Upon reading this word, it is obvious that this term is related to desmosomes, which are part of the anchoring junctions that participate in cell to cell communication in epithelial tissue. The desmosomal attachment plaque, however, is "a disc-shaped structure consisting of very dense material on the cytoplasmic side of the plasma membrane of each adjoining cell." This structure also "anchors intermediate filaments, which play a role in dissipating physical forces throughout the cell from the attachment site. Each attachment plaque is composed of several constitutive proteins, mainly desmoplakins and plakoglobins, which are capable of anchoring the intermediate filaments." "Desmoplakins" and "plakoglobins" were also unfamiliar to me until I encountered them this week in our textbook, along with "desmosomal attachment plaque." The desmosomal attachment plaque, then, is really a structure on the cytomplasmic side of the plasma membrane that anchors intermediate filaments, and desmoplakins and plakoglobins are the proteins associated with this structure that anchor these intermediate filaments.


The textual information above was taken from the following reference: 
Ross, Michael H., and Wojciech Pawlina. "Anchoring Junctions." Histology: A Text and Atlas: With Correlated Cell and Molecular Biology. 6th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health, 2011. 131. Print.


The pictorial information above was taken from the following reference:
http://heart.bmj.com/content/97/7/530/F1.large.jpg