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Full-Text Articles in Life Sciences

Evolution And Natural Selection Of Olfactory Receptor Genes In Hawaiian Drosophila, Ngoc H. Ly Dec 2023

Evolution And Natural Selection Of Olfactory Receptor Genes In Hawaiian Drosophila, Ngoc H. Ly

UNLV Theses, Dissertations, Professional Papers, and Capstones

The olfactory system is a powerful tool for sensing countless odorants. In Drosophila, the olfactory system is critical for detecting food, finding mates, laying eggs, avoiding predators, and adapting to new environments. Understanding the olfactory system in Drosophila will advance our knowledge of sensory biology in various insects and vertebrates, including humans. Drosophila has been a valuable model for biology since the early 1900s, and the Drosophila melanogaster olfactory system is well-studied. The Hawaiian Drosophila represent approximately 1/3 of the world’s Drosophila, however, there is limited research on Hawaiian Drosophila olfactory genes. We conducted a comparative analysis of …


Cellular Heat Responses Of Desert Mammals Promote Survival In Extreme Conditions, Janessa Montenegro Aug 2023

Cellular Heat Responses Of Desert Mammals Promote Survival In Extreme Conditions, Janessa Montenegro

UNLV Theses, Dissertations, Professional Papers, and Capstones

Increasing temperatures with the potential for heat stress is among the future threats facing many mammals. Cellular mechanisms to maintain homeostasis in the face of heat stress likely differ across species based on naturally tolerated intracellular variability. In some mammals, the homeostatic set point in cells has a narrow range. Other species tolerate more varied intracellular conditions, including in temperature. Heat stress responses of cultured dermal fibroblasts from several mammals were compared to detect cell proliferation and cellular death (chapter 2). Cells from heat- tolerant species (13-lined ground squirrel, dromedary camel, round-tailed ground squirrel, and white-tailed antelope squirrel) were compared …


Cell-Specific Mechanisms Of Microrna Modulation Of Anoctamin-1 (Ano1) In Oral Cancer, Daniel Hou May 2023

Cell-Specific Mechanisms Of Microrna Modulation Of Anoctamin-1 (Ano1) In Oral Cancer, Daniel Hou

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anoctamin-1 (ANO1) is a calcium-gated chloride ion channel with multiple physiological roles, including transepithelial ion transport, smooth muscle contraction, salivary secretion, and nociception. Recently, ANO1 has been identified to play a key role in cancer progression. ANO1 is overexpressed in different types of cancer, including oral cancer. ANO1 overexpression is commonly the result of ANO1 gene amplification on the chromosome 11q13 locus. In cancer cells, ANO1 upregulation has been reported to promote cell proliferation and migration of tumor cells, whereas ANO1 downregulation induces apoptosis through multiple signaling pathways. As such, ANO1 is now considered a useful biomarker for cancer progression …


Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel May 2023

Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert springs are aquatic oases, being considered among the most diverse and imperiled ecosystems on Earth. Despite the ecological significance and threatened status of desert springs, few studies have surveyed the microorganisms in these systems or their interactions with other community members. The primary goal of this dissertation was to describe the major controls influencing the community ecology of prokaryotic and BMI communities in cold- and moderate-temperature desert springs of the southern hydrographic Great Basin. Chapter 1 provides a broad overview of spring ecosystems and of each chapter included in this dissertation. Chapter 2 documents the first-ever, regional-scale survey of …


Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington May 2023

Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington

UNLV Theses, Dissertations, Professional Papers, and Capstones

The bacterium Fervidibacter sacchari is an aerobic hyperthermophile that catabolizes various polysaccharides and is the only cultivated member of the class Fervidibacteria within the phylum Armatimonadota. Among its glycoside hydrolase (GH) cache is an enzyme from GH family 50 (GH50), an understudied family with only 25 characterized representatives and two known activities from 1,518 predicted members in the Carbohydrate-Active EnZyme (CAZy) Database. Here, we expressed, purified, and functionally characterized an extracellular GH50 from F. sacchari called Fsa1572. Using colorimetric assays, we show it has novel β-1,4-glucanase activity and only weak agarose activity that is typical for GH50 enzymes. The purified …


Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan May 2023

Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea. Due to its insidious nature, the Centers for Disease Control and Prevention (CDC) has declared CDI an urgent threat. A key characteristic of C. difficile is its ability to form dormant spores that act as the infectious vehicles for disease. In the gut, spores recognize bile salts to germinate into toxin-producing cells.Dysbiosis of the gut microbiome is a key factor in allowing the C. difficile spores to germinate. Normal gut microbiota naturally protects from CDI. However, biological variables such as diet and sex have been found to modulate to …


The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar May 2023

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …


Optimizing Resin Infiltration Treatment Of Post-Orthodontic White Spot Lesions By Increasing Infiltrant Penetration Duration — In Vitro Study, Hahnnah Park May 2023

Optimizing Resin Infiltration Treatment Of Post-Orthodontic White Spot Lesions By Increasing Infiltrant Penetration Duration — In Vitro Study, Hahnnah Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: This study focuses on evaluating the effect of increasing duration allowed for resin infiltrant penetration in improving the aesthetic outcome of resin infiltration treatment. Additional investigations into repeat treatment and long-term stability were also conducted. Artifically created white spot lesions were induced on one hundred extracted teeth made up of either incisors or canines. Teeth were divided into enamel and dentin groups depending on the extent of the lesion and then further subdivided into varying treatment protocol groups: 3-minute, 6-minute, and 9-minute penetration time. Teeth were thermocycled for one clinical year and then divided into a repeat treatment and …