C'mon out and learn something! Bring a friend and bring a lunch!
. . . The bartender comes over and says to the Sloth "What'll it be?" The Sloth says "A shot and a beer would make me happy, but no need to serve my friend here. He doesn't need cheering up because he's a Fun Guy!"
Both graduate heroines gave remarkable presentations on their areas of interest. Marissa presented on Electromyography EMG activation in the forelimb muscles of three-toed sloths (Bradypus Variegatus). She enumerated the muscles’ mechanisms of contraction and relaxation under the guidance of Henneman’s size principle that states that,’ “under any weight/load, the motor units are recruited from smallest to largest”. The most fascinating part is that her research correlated with the Henneman’s principle where flexor muscles (e.g Biceps brachii) and extensor muscle (e.g Triceps brachii) dominated as the most active muscles with high burst intensity for sloth’s behavioral adaptation.
ReplyDeleteKayla followed with her hilarious presentation on the effects of YakA deficiency in T. marneffei infection of THP-1 and J774 macrophage cell lines, where she’s aiming to infect these cell lines with WT and Yak. T. marneffei is a thermally dimorphic and an opportunistic fungal pathogen. Its pathogenicity depends on the ability to engulf and replicate within the macrophage, it causes infection to both immunocompetent and immunocompromised patients, but its significantly high in non-HIV immunocompromised patients
My first question from Marissa’s project is, do you think this project has any significant importance for the survival of sloth generation? Finally, from Kayla’s presentation, why is T. Marneffei infection significantly high in non-HIV immunocompromised patients?
Both Kayla and Marissa did a wonderful job and I really enjoyed both of their presentations.
ReplyDeleteMarissa’s research on EMG activation of the muscles was really cool and I love how it was supplemented with actual video of the sloth’s movement. To answer Stephen’s question, I definitely think this type of research is significant for sloth survival. Understanding the mechanisms of how sloths move and interact with their environment could allow for many different concentrations of biology to be able apply this type of data to future research, conservation efforts, or even replicating muscle type in lab. I feel like it would also be useful data for comparing the function and success of other similar animals.
Kayla’s presentation was great. Not only did she discuss some really awesome research, but she also kept things light and gave us a few laughs. I think for hers, infection is higher in immunocompromised individuals (and not only those with HIV) because the immune system is less capable of fighting off infection and will probably show more in individuals whose macrophage activity is altered, however I’m no immunologist so I have no idea if I’m on the right track here.
I think Kayla did a really awesome job and I enjoyed her added humor and stuffed macrophages! For the question regarding my talk, I think that my project can be applied to the survival of the sloth generation. These awesome animals are not very well studied. So Kyle’s and my research, along with the other research currently being done, we can overall contribute to the education and conservation efforts for these animals. Especially for the Bradypus pygmaeus and Bradypus torquatus species which are critically endangered and vulnerable, respectively. For the question regarding Kayla’s research, I would agree with Jamielynn that in immunosuppressed patients the infection is higher because the immune system is compromised so it is harder to fight off the infection.
ReplyDeleteI agree with the consensus that both Marissa and Kayla gave excellent and engaging presentations last Friday. Regarding Stephen’s question asking of the significance of Marissa’s research in the survival of sloths, I agree with Jamielynn in that it is an important piece of the puzzle in understating this species. As Marissa said when questioned at the end of her talk, Sloth’s do not have very advanced defense mechanisms, so a better understanding of their musculature via EMG analyses definitely provides a better incite to these fascinating animals and to their survival rates. As far as the question regarding Kayla’s work, I think that the rate of infection is higher in immunocompromised individuals simply because of a suppressed immune system and a lack in ability to fight off this type of fungal infection.
ReplyDeleteAnother excellent job to our graduate students on presenting their research projects. To answer Stephens first question about Marissa’s presentation, I do believe that this research is important for the survival of sloth generation. I think that being able to further understand sloth’s movement and biological mechanisms, it can be great for further research into them. Like said before, sloths are not well studied animals, so this research can be useful on future studies. For the question about Kayla’s research, I would have to agree with everyone and say that the infection rate is higher in immunocompromised individuals because they have difficulty fighting off infection resulting from their suppressed immune system.
ReplyDeleteGo Marissa and Kayla! It’s exciting to hear so many stellar talks from the graduate students this semester. Sloths have led a successful existence up to now, and part of their success is thanks to energy-saving suspensory behaviors. Dr. Butcher described sloths as “upside-down horses” to me when we first met, and I think that the comparison holds up. Marissa’s EMG activity patterns indicate that muscle activity is minimized, especially during static hanging. This means that they spend little metabolic energy while in suspension, which is a good thing when for an animal that doesn’t eat much and subsists on a low energy diet. Her work suggests that sloths rely on passive force mechanisms where tendons are loaded under tension instead of muscle tissue. Similarly, horses use passive locking mechanisms to stabilize their limb joints so that they can stand for 23 hours a day without spending absurd amounts of metabolic energy to maintain posture. It’s all about minimizing the metabolic cost of posture and locomotion.
ReplyDeleteI agree that the reason immunocompromised individuals have trouble fighting off the fungal infection because of suppressed immune response. T. marneffei infections thus pose a major threat. Besides that, fungal infections give me the heebie jeebies. Kayla, would you please remind me the function of the protein encoded by YakA? If I am remembering correctly, they were involved in the removal of cytokines so that the immune signal is lost. Also, do you know any genes involved in the transition from mold to yeast? I ask because I think that a great way to fight T. marneffei infections is to inactivate genes so that the infection can’t transition, causing a loss of virulence.
I was honored to present with such a stellar woman in science. I found Marissa’s presentation both well-executed and engaging. I actually felt quite relaxed watching the sloth videos too which made me feel more comfortable when it was my turn to talk. To answer Stephen’s question about her work, I think her work is vitally important to the sloth generations because much conservation efforts stem from our wonder about different organisms. The more we discover about sloths and other animals, the more appreciation and value are shown to them which could be the difference between protecting them or ignorantly destroying them.
ReplyDeleteTo answer the question about my research, the reason why talaromycosis is becoming less common in non-HIV patients is because the anti-retroviral treatments used to treat AIDS are becoming very effective at keeping immune cell populations up enough to be able to fight T. marneffei. People whose immune systems are compromised by conditions other than AIDS, like people receiving cancer treatment or immune suppressant drugs for organ transplants, are more susceptible to talaromycosis since their immune systems cannot successfully eradicate the fungi.
The yakA protein has been shown in homologs to function in carbon source response, growth regulation, and stress response. Being able to have an effective stress response may allow the fungi to avoid immune detection inside of macrophages but there hasn’t been any link between yakA and removal of cytokines, that was purely speculative on my part Kyle. I don’t know any specific genes involved in the transition from mold to yeast but I do know a few undergrads (Justina and Victoria) are examining gene expression from mold to yeast transition. They have identified a yeast phase specific protein that I think you’ll hear about Friday. That is an excellent way to fight T. marneffei though, inactivating genes.
Great job, guys! Fascinating research! To answer the first question, I do think Marissa's research contributes to the success for a sloth's survival. Understanding which muscles are activated and to what degree during various locomotor habits is essential to know. As we all saw, sloths exhibit very slow movements, and, like Kyle mentioned, her research suggests the EMG patterns are more minimal. As I like to say, they are on energy-saving mode. This conservation of energy is advantageous for their survival. To answer the second question, those with a compromised immune system (such as being an HIV patient) would having a harder time fighting off the fungal infection, which would result in higher infection. In contrast, a more normal immune system would have lower fungal infection if any exposure occurred.
ReplyDeleteMarissa's research was really neat (and I think pretty too - the synchronization and colors). I don't know if I can elaborate on whether or not this research directly correlates to helping sloths survive (if I understood the question correctly), but I absolutely think it is important, and contributes to a greater body of knowledge that has multitudes of applications as it grows and circumstance arise (that’s super general on purpose!). Great job Marissa!
ReplyDeleteKayla’s presentation caught me off-guard. I wasn’t expecting to have my sides hurt when I left (the freeloader joke was awesome). This is pure conjecture, but I think T. Marneffei infection is higher in non-HIV immunocompromised patients (as compared to past non-HIV immunocompromised patients, rather than the HIV immunocompromised) for a few reasons: 1) Better detection of the bug due to better healthcare access and testing, 2) HIV patients may serve as carriers, and HIV is a relatively new disease, 3) more reasons to be non-HIV immunocompromised, such as better care for those congenitally so, as well as treatments that kill WBCs like chemo, and 4) treatment of AIDS patients infected with T. Marneffei undoubtedly occurs in the hospital, creating greater potential for these nosocomial infections of the other non-HIV immunocompromised patients.
Two more great presentations that I really enjoyed! Regarding Marissa's presentation, the best way to save and conserve a species is to understand it. I think more research and further studies conducted on sloths can help us better understand them. Knowing how their body functions and works can relate to ways to keep population numbers up. Concerning Kayla’s research, I would have to agree with everyone. I think the infection rate would higher in immunocompromised individuals. They are not able to defend against infections.Their poor immune system does not give them any chance of defending their body.
ReplyDeleteAnother two great examples of the research our biology graduate students are accomplishing!
ReplyDeleteFor Stephen’s question about Marissa’s presentation, I believe that everyone is in agreement here that knowing more about B. variegatus and other sloths will contribute to human efforts to protect and conserve these species, which can only benefit future sloth generations. As Kyle pointed out, these sloths demonstrate a unique example of passive tension loading on tendons, rather than active muscle contraction, as a means to conserve energy. As for Kayla’s presentation, not without its hilarious anecdotes, I never would have expected to find fungi replicating inside a macrophage. I am also in agreement with everyone here that, although HIV patients and non-HIV immunosuppressed both have their immune systems compromised, they are compromised in different ways. Clearly, the type of immunosuppression seen in non-HIV individuals makes them more susceptible to T. marneffei infection, probably because components of innate immunity are principal in fighting off the yeast, and loss of them makes the individual vulnerable.
Both Kayla and Marissa did a wonderful job and I really enjoyed their presentations. For Marissa’s presentation, it is important to understand metabolism of biceps brachii as flexors and triceps as extensors saves energy for a sloth, hence reducing the need of getting food more often. Kayla’s research was also very fascinating. It was very informative and Kayla kept us attentive with her unique sense of humor. I think there might be a missing link in the maturation process of CD4+ T cells that make non HIV patients more susceptible to T. marnefeii infection.
ReplyDeleteNo comments about my joke? I'm disappointed.
ReplyDelete