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By Charlie Rumrill, V Form
Type 2 Diabetes as a Global Epidemic
Type 2 Diabetes mellitus is a group of chronic disorders caused by either the number of pancreatic beta-cells, their ability to function, or the skeletal muscle and liver cells ability to transduce insulin’s signal, all of which result in hyperglycemia. Due to genetic, environmental, and epigenetic factors, Type 2 Diabetes has rapidly become a global epidemic.
In order to understand the pathophysiology, or diseased state, of Type 2 Diabetes, a comprehension of how the body typically regulates carbohydrate metabolism is required. As shown in figure 1, the catabolism, or breakdown, of carbohydrates begins as soon as it is ingested, with salivary amylase enzymes hydrolyzing the large polysaccharides into smaller oligosaccharides. When the salivary mixture is swallowed, it continues through the esophagus to the stomach which denatures the enzymes with its highly acidic environment. Since no enzymes can function in the stomach, the digestion of the carbohydrates temporarily stops until it continues to the small intestine, where more amylase enzymes produced by the acinar cells in the pancreas meet the fluid in the small intestine and continue to hydrolyze the oligosaccharides into simpler disaccharides. As the mixture continues through the small intestine, brush border cells with enzymes attached hydrolyze the disaccharides into simpler monosaccharides, such as glucose. Only now can the once large polysaccharides be absorbed into the bloodstream. From the small intestine, the blood circulates directly to the pancreas, where the pancreatic beta-cells secrete insulin due to the elevated blood-glucose levels. Then, the blood flows to the liver and the rest of the body (Figure 1) where the liver and skeletal muscle cells bind to insulin, triggering more glucose transporters to be embedded in the cellular membrane. Due to the cells having more transporters, more glucose molecules can enter the cell, and the glycogen phosphorylase enzymes can bind them together through dehydration synthesis to form glycogen. Insulin also travels to the adipose tissue, where the glucose is then stored as fats. In addition to the effects of insulin, glucose molecules are constantly being taken into every cell in order for it to have the energy to complete its functions. Over time, due to the glycogen being produced and cells constantly needing glucose the body’s blood-glucose levels then lower. When the blood-glucose levels decrease, the pancreatic alpha-cells secrete the hormone glucagon which, when bound with the skeletal muscle and liver cells, triggers the glycogen to be hydrolyzed and released back into the bloodstream as glucose.
By Tony Banson and Tommy MacNeil, V Form
What Is Cancer: Looking Through the Multiplex Lens of Immortality
Cancer is a disease that has touched the lives of many around the world (Figure 1). It is a disease that afflicts both the young and old, and the rich and poor. The American Cancer Society estimates that there will be 1,688,780 new cancer cases diagnosed and 600,920 cancer deaths in the United States in 2017 (Cancer Facts & Figures 2017). Biologically, this disease arises from one’s body when normal, healthy cells begin to grow uncontrollably. Because of genetic and environmental factors, the subset of cells no longer cooperate with evolution’s safety controls, bypassing important regulatory checkpoints of the cell cycle. With the advent of technology and medicine, humans are living longer and the cells that make up our bodies have more time to mutate in ways that can cause havoc.
From a personal standpoint, cancer has touched the lives of many of our loved ones. (more…)
By Lindsey Dumond and Sada Nichols-Worley, V Form
Editor’s Note: After completing a deep examination of the process of Cellular Respiration, Advanced Biology students were randomly assigned to small groups (2-3) students and tasked with tackling a case study. The case of “The Mystery of the Seven Deaths” examined the true story of cyanide poisoning that occurred in the early 1980s. This case study required students to analyze data, make conclusions, and explain mechanisms of action. The students were then required to present the case to a lay person in 3 minutes through a 1-Take Video. A 1-Take Video is exactly what the name implies: a video shot in 1-take. This entire assignment was completed in an 80-minute block.
Click on the image below for the video!
By David Baek, VI Form
The Circadian Clock and The Adverse Effects of Elevated CAT Level
Introduction: This project probes into the molecular mechanism of the circadian clock of Drosophila Melanogaster. The circadian clock exists in all living things and regulates the daily rhythm of organisms’ metabolism, behavior, and other outputs that affect the organisms’ development (CH Ko, 2006). The circadian clock is a field that researchers and scientists have yet to fully understand due to the ambiguity of how circadian clock affect invertebrates and vertebrates. To uncover one small aspect of this obscurity, this study seeks to find the effect of sleep deprivation on antioxidant defense in fruit flies. If there were to be a link, the investigation would be significant as the effect will explain how sleep deprivation in humans can lead to the weakening of their antioxidant defense, leading to multiple cardiovascular diseases and pathological conditions such as plaque formation in vessels (Takeda, 2011) (Dominguez-Rodriguez et al, 2009). (more…)
By Lilly Drohan, VI Form
From Classroom To Lab: My Work With T Cell Therapy
This summer, I traveled to Seattle, Washington to work in the Ben Towne Center for Childhood Cancer Research at the Seattle Children’s Research Institute. My biology teacher presented me with the opportunity, and I immediately got my hands on it. Studying cancer at the microbiological level in Advanced Biology my junior year really challenged me and stimulated my curiosity, but what I experienced during August turned my attraction into almost an obsession. Dr. Michael Jensen, the director of the lab, takes an approach to pediatric cancer therapy that not many take: using the body’s own immune system to fight off the cancer. Dr. Jensen and his team reprogram immune cells called T cells using virus technology to give the cells specific properties that help them proliferate and target specific molecules expressed on cancer cells. This form of therapy is incredibly innovative and creative, and it was so captivating to be at the forefront of the further development of the treatment for just a brief month.