Proto-RNA Synthesis Using Glycerol and Phosphate Anion

Nucleic acids are important molecules for all life, serving as the primary molecules for information storage and reproduction. RNA has long been thought to be the molecule that initiated protein synthesis. However, RNA has recently been thought to be too complex to synthesize prebiotically. Through a 1:1 mole ratio condensation of glycerol and phosphoric acid, I generated glycerol-phosphate oligomers that resemble a primitive form of the carbon-phosphate backbone of RNA. 75 mmol MgCl2 was added to some samples to see if the Mg cation could stabilize the reaction intermediates and further promote longer proto-RNA oligomers. These samples were all heated at 120 °C for 96 hours. Using NMR, the products of this reaction were characterized, and successful phosphate binding to glycerol was observed. Mass spectrometry was used to determine the length of the oligomers that were formed. I observed successful production of oligomers as long as pentamers, with significantly less production in samples containing Mg2+. Additionally, the products were observed under a light microscope to see the formation of any physical structures. Vesicle-like structures were observed, ranging from 10-30 microns in size. This indicates the potential ability of glycerol-phosphate oligomers to spontaneously arrange into vesicles according to its intramolecular hydrophobicity

Use of autologous adipose-derived mesenchymal stem cells for creation of laryngeal cartilage

OBJECTIVES/HYPOTHESIS: Adipose-derived mesenchymal stem cells (ASCs) are an exciting potential cell source for tissue engineering because cells can be derived from the simple excision of autologous fat. This study introduces a novel approach for tissue-engineering cartilage from ASCs and a customized collagen oligomer solution, and demonstrates that the resultant cartilage can be used for laryngeal cartilage reconstruction in an animal model. STUDY DESIGN: Basic science experimental design. METHODS: ASCs were isolated from F344 rats, seeded in a customized collagen matrix, and cultured in chondrogenic differentiation medium for 1, 2, and 4 weeks until demonstrating cartilage-like characteristics in vitro. Large laryngeal cartilage defects were created in the F344 rat model, with the engineered cartilage used to replace the cartilage defects, and the rats followed for 1 to 3 months. Staining examined cellular morphology and cartilage-specific features. RESULTS: In vitro histological staining revealed rounded chondrocyte-appearing cells evenly residing throughout the customized collagen scaffold, with positive staining for cartilage-specific markers. The cartilage was used to successfully repair large cartilaginous defects in the rat model, with excellent functional results. CONCLUSIONS: This study is the first study to demonstrate, in an animal model, that ASCs cultured in a unique form of collagen oligomer can create functional cartilage-like grafts that can be successfully used for partial laryngeal cartilage replacement

Haemosporidian Parasite Community In Migrating Bobolinks On The Galapagos Islands

Bobolinks (Dolichonyx oryzivorus) migrate from their breeding grounds in North America to their wintering grounds in South America during the fall each year. A small number of Bobolinks stop temporarily in Galapagos, and potentially carry parasites. On the North American breeding grounds, Bobolinks carry a least two of the four Plasmodium lineages recently detected in resident Galapagos birds. We hypothesized that Bobolinks carried these parasites to Galapagos, where they were bitten by mosquitoes that then transmitted the parasites to resident birds. The haemosporidian parasite community in 44% of the Bobolinks we captured was consistent with those on their breeding grounds. However, the lineages were not those found in Galapagos birds. Our results provide a parasite community key for future monitoring

Local Parasite Lineage Sharing In Temperate Grassland Birds Provides Clues About Potential Origins Of Galapagos Avian Plasmodium

Oceanic archipelagos are vulnerable to natural introduction of parasites via migratory birds. Our aim was to characterize the geographic origins of two Plasmodium parasite lineages detected in the Galapagos Islands and in North American breeding bobolinks (Dolichonyx oryzivorus) that regularly stop in Galapagos during migration to their South American overwintering sites. We used samples from a grassland breeding bird assemblage in Nebraska, United States, and parasite DNA sequences from the Galapagos Islands, Ecuador, to compare to global data in a DNA sequence registry. Homologous DNA sequences from parasites detected in bobolinks and more sedentary birds (e.g., brown-headed cowbirds Molothrus ater, and other co-occurring bird species resident on the North American breeding grounds) were compared to those recovered in previous studies from global sites. One parasite lineage that matched between Galapagos birds and the migratory bobolink, Plasmodium lineage B, was the most common lineage detected in the global MalAvi database, matching 49 sequences from unique host/site combinations, 41 of which were of South American origin. We did not detect lineage B in brown-headed cowbirds. The other Galapagos-bobolink match, Plasmodium lineage C, was identical to two other sequences from birds sampled in California. We detected a close variant of lineage C in brown-headed cowbirds. Taken together, this pattern suggests that bobolinks became infected with lineage B on the South American end of their migratory range, and with lineage C on the North American breeding grounds. Overall, we detected more parasite lineages in bobolinks than in cowbirds. Galapagos Plasmodium had similar host breadth compared to the non-Galapagos haemosporidian lineages detected in bobolinks, brown-headed cowbirds, and other grassland species. This study highlights the utility of global haemosporidian data in the context of migratory bird–parasite connectivity. It is possible that migratory bobolinks bring parasites to the Galapagos and that these parasites originate from different biogeographic regions representing both their breeding and overwintering sites

Safety Recommendations for Evaluation and Surgery of the Head and Neck During the COVID-19 Pandemic

Importance The rapidly expanding novel coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2, has challenged the medical community to an unprecedented degree. Physicians and health care workers are at added risk of exposure and infection during the course of patient care. Because of the rapid spread of this disease through respiratory droplets, health care workers who come in close contact with the upper aerodigestive tract during diagnostic and therapeutic procedures, such as otolaryngologists–head and neck surgeons, are particularly at risk. A set of safety recommendations was created based on a review of the literature and communications with physicians with firsthand knowledge of safety procedures during the COVID-19 pandemic. Observations A high number of health care workers were infected during the first phase of the pandemic in the city of Wuhan, China. Subsequently, by adopting strict safety precautions, other regions were able to achieve high levels of safety for health care workers without jeopardizing the care of patients. The most common procedures related to the examination and treatment of upper aerodigestive tract diseases were reviewed. Each category was reviewed based on the potential risk imposed to health care workers. Specific recommendations were made based on the literature, when available, or consensus best practices. Specific safety recommendations were made for performing tracheostomy in patients with COVID-19. Conclusions and Relevance Preserving a highly skilled health care workforce is a top priority for any community and health care system. Based on the experience of health care systems in Asia and Europe, by following strict safety guidelines, the risk of exposure and infection of health care workers could be greatly reduced while providing high levels of care. The provided recommendations, which may evolve over time, could be used as broad guidance for all health care workers who are involved in the care of patients with COVID-19

Senior Recital: Andrew R. Creech, Percussion

This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Music Performance. Mr. Creech studies percsussion with John Lawless and Michael Stubbart.https://digitalcommons.kennesaw.edu/musicprograms/2273/thumbnail.jp

A gut microbiome tactile teaching tool and guided-inquiry activity promotes student learning

The gut microbiome and its physiological impacts on human and animal health is an area of research emphasis. Microbes themselves are invisible and may therefore be abstract and challenging to understand. It is therefore important to infuse this topic into undergraduate curricula, including Anatomy and Physiology courses, ideally through an active learning approach. To accomplish this, we developed a novel tactile teaching tool with guided-inquiry (TTT-GI) activity where students explored how the gut microbiome ferments carbohydrates to produce short chain fatty acids (SCFAs). This activity was implemented in two sections of a large-enrollment Human Anatomy and Physiology course at a research intensive (R1) university in the Spring of 2022 that was taught using a hyflex format. Students who attended class in person used commonly available building toys to assemble representative carbohydrates of varying structural complexity, whereas students who attended class virtually made these carbohydrate structures using a digital learning tool. Students then predicted how microbes within the gut would ferment different carbohydrates into SCFAs, as well as the physiological implications of the SCFAs. We assessed this activity to address three research questions, with 182 students comprising our sample. First, we evaluated if the activity learning objectives were achieved through implementation of a pre-and post-assessment schema. Our results revealed that all three learning objectives of this activity were attained. Next, we evaluated if the format in which this TTT-GI activity was implemented impacted student learning. While we found minimal and nonsignificant differences in student learning between those who attended in-person and those who attended remotely, we did find significant differences between the two course sections, which differed in length and spacing of the activity. Finally, we evaluated if this TTT-GI approach was impactful for diverse students. We observed modest and nonsignificant positive learning gains for some populations of students traditionally underrepresented in STEM (first-generation students and students with one or more disabilities). That said, we found that the greatest learning gains associated with this TTT-GI activity were observed in students who had taken previous upper-level biology coursework