garfboxylgroup – BioQuakes

Do you know anyone who has needed an organ transplant? Hopefully, the answer is no. However, many medical dramas on television have shown us the awful process patients go through when waiting on a transplant list for a heart, lung, kidney, etc.

For years, scientists have experienced many trials and errors. They explored pig parts and ways to supplement them as human organs. However, a huge advancement in gene editing has just reinstated hope for many suffering patients. On March 16th, Richard Slayman received a pig kidney. He had type two diabetes and had been on dialysis. He had a transplant several years ago, but the organ showed signs of failure. Doctor Winfred Williams explained that Slay would not have survived if he had to wait another five years for a human kidney transplant.

Eventually, the idea was proposed for Slayman to receive a genetically engineered pig kidney from eGenesis, a biotechnology company. Their goal is to generate human-compatible organs that can be used in transplants. In Slayman’s case, this kidney had been genetically altered 69 times using the CRISPR-Cas9 gene editing system, which allows certain parts of a genome to be removed or even added. Slayman’s new kidney was made suitable for him in a very meticulous way. Firstly, three genes that are typically found in pigs that attack human immune systems were removed. These were genes that code for the synthesis of certain carbohydrates. Additionally, seven human genes were added to the genome that prevent an immune response that may lead to transplant rejection. Certain pig viruses were also removed as they pose a harm to humans.

This is very relevant to one of our last AP Biology units. We just learned about mRNA processing. This step occurs following mRNA transciption, with the goal of making certain proteins. After the nitrogenous bases are transcrribed from template DNA, the mRNA is processed in several ways. A Guanine cap is added to the front of the strand and a Poly-A tail is added to the end. Additionally, parts of the mRNA are cut out. In CRISPR editing, this same process is done by scientists artificially, rather than our natural processes. The parts of mRNA that are cut out that will not make a protein are called introns, while the kept parts of mRNA are called exons. mRNA splicing can also take place where different combinations of bases are organized to make certain amino acid chains.

This new advancement will not only help patients receive new organ quicker, but it is the doctors’ hope that this will solve a larger cultural issue, in that ethnic minorities often struggle to receive organ transplants. This new process will hopefully benefit the healthcare system both medically and culturally.

Why are Blueberries Blue?

By garfboxylgroup

On March 8, 2024

In Student Post

Have you ever wondered how certain fruits are such vibrant colors? Scientists globally have also pondered such characteristics. Some people think that objects obtain their colors by simply having the pigment inside. However, how our eyes perceive color is much more complicated than simply seeing the pigmentation.

Recently, research has been conducted on the color of blueberries. Blueberries are considered to be a “bloom” fruit, in that it has an epicuticular wax layer and dark pigmentation. This color does not come from smushing the fruit and watching the juice emerge, which led researchers to wonder where exactly it does come from. Researchers have discovered that blueberries are covered by a thin, waxy coating that is two microns thick. The researchers discovered this by removing the waxy layer and recrystallizing it to view the particles within the layer itself.

Within this layer, there are scattered particles in a random crystalline structure that reflect blue and UV light. Photons of light have certain pigments, and only a few of which are visible to humans. The photo below depicts which light is visible to humans. It is also notable that the pigment in blueberries reflects UV light, which is visible to birds.

This directly relates to our AP Bio Photosynthesis Unit. In this unit we learned the reason why leaves are green. This is because leaves contain certain pigments (one being chlorophyll a) that absorb all wavelengths of light except for green, which is reflected.

Additionally, we learned in AP Bio that leaves are surrounded by a non-polar, waxy substance. This is the same on blueberries. It is interesting that learn that water will not easily penetrate through the skin of leaves as well as certain fruits due to the repulsion of non-polar and polar substances.

Do you know of any other epicuticular fruits? Can we investigate their pigmentation as well?

New Injection Provides Hope for Regaining Smell Following COVID-19 Infection

By garfboxylgroup

On December 5, 2023

In Student Post

Did you or someone you know ever contract COVID-19 and lose your sense of taste or smell? This is called Parosmia. There are people on social media who have tried to theorize ways to regain the ability to smell normally. For example, burning an orange peel. However, if your nasal cavity is damaged, regardless of the strong orange aroma, it may be believed that you will not be able to regain your sense of smell.

So, how was your nose damaged in the first place? The olfactory system contains a zone that detects scents towards the top of the nasal cavity. When molecules diffuse up into the nose, they dock in receptor proteins which ultimately initiates a cascade to create a cellular response. Hence, we are able to smell aromatic molecules.

When someone is infected with the SARS-CoV2 virus, the olfactory epithelial cells are damaged. Doctors have analyzed singular cells following a biopsy in order to examine the effect of the virus on healthy cells. They were able to conclude that the body ignited a innate immunity response, in which swelling occurred where the nerve endings are located. While in some cases the swelling decreased following the innate response, other times, the swelling remained and damaged the tissue.

This can be explained by what we have learned in AP Biology. During an innate immune response, cells release histamines. These dilate blood vessels, while macrophages secrete cytokines. Cytokines attract phagocytes that allow the infected cells and pathogens to be destroyed. The proteins that attempt to interfere with the viruses cause more histamine to be released and overall more swelling. Therefore, the nasal cavity can remain damaged.

However, new research has found that an injection just might help patients with long COVID symptoms to regain their sense of smell. According to Dr. Adam Zoga, one way that patients have begun to smell again is by injecting stellate ganglion blocks into the neck on either side of the voice box. This reaches the stellate ganglia which contains nerve bundles that control your body’s fight-or-flight responses, known as the sympathetic nervous system. Patients also received a steroid injection to decrease swelling.

The patients that participated in the study did not all benefit from it. However, 22 of the 37 that followed up with administrators following the trial injection noticed improvements in one week. Dr. Leigh Sowerby analyzed this data and theorizes that this may work to treat Parosmia because the sense of smell is affected when the sympathetic nervous system is overactive. He believes that this injection “resets” the nervous system, allowing the nerve bundles to return to normal and patients to regain their sense of smell. However, because only 37 of the original 54 patients followed up after the injections, and there was no control group, researchers cannot further extended this claim.

Why Does our Hair Flow the Way it Does?

By garfboxylgroup

On October 19, 2023

In Student Post

Do you ever wonder why your hair always naturally parts the same way? Our hair patterns can be described as our “hair whorl.” This denotes the direction in which the hair follicles orient themselves, as well as the number of times the hair rotates in a circular pattern. This can be either a single or double whorl. While this physical characteristic maybe be obvious to the naked eye, it is unclear why these patterns initially occur.

In a recent study, the National Survey of Physical Traits cohort came together to understand whether or not our hair patterns could be determined by genetic characteristics. In China, Lead Investigator Sijia Wang determined that hair whorl can be a result of four genetic variances, also known as a polygenic inheritance. These variances occur at 7p21.3, 5q33.2, 7q33, and 14q32.13, which are specific locations on a DNA sequence. These variances affect hair patterns due to both cell polarity as well as cranial neural tube closure and extension.

This relates to AP Biology due to the effect of cell polarity on the hair whorl. In class we learned that non-polar (hydrophobic) molecules will move away from polar molecules. Hair cells are classified as epithelial cells, meaning they exist on the outer-most layer of our skin’s surface. They are polarized in sheet known as the planar cell polarity (PCP). The author’s logic makes sense in that a pattern will occur in the hairline if the polar molecules are moving away from those that are non-polar, or vice versa.

Additionally, because the whorls can be associated with neural tube closures and growths, it was believed that abnormally placed or shaped whorls can be related to a neurological deficit. However, Dr. Wang’s research did not confirm whether or not this was true.

Now it’s your turn — can you find your hair whorl?

BioQuakes

AP Biology class blog for discussing current research in Biology

Author: garfboxylgroup

CRISPR Gene Editing Provides Hope for Patients on Transplant List

Why are Blueberries Blue?

New Injection Provides Hope for Regaining Smell Following COVID-19 Infection

Why Does our Hair Flow the Way it Does?

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