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Glial Cell Mechanisms Regulate Alcohol Sedation In Drosophila Melanogaster, Kristen M. Lee 2019 Virginia Commonwealth University

Glial Cell Mechanisms Regulate Alcohol Sedation In Drosophila Melanogaster, Kristen M. Lee

Theses and Dissertations

Approximately 16 million people in America are diagnosed with Alcohol Use Disorder (AUD) but no efficacious medical treatments exist. Alcohol-related behaviors can be studied in model organisms, and changes in these behaviors can be correlated with either (i) a risk for alcohol dependence or (ii) a symptom/feature of AUD itself. Although AUD is a disease of the central nervous system, a majority of research has focused on the neuronal underpinnings, leaving glial contributions largely undescribed. We used Drosophila melanogaster (fruit fly) to identify genes whose expression in glia regulates alcohol sedation. Mammals and Drosophila have conserved behavioral responses to alcohol …


First Record Of White Stork In A Birdstrike In South Africa Above 3,300 M Agl, Desire Dalton, Marli De Bruyn, Monica Mwale, Kim Labuschagne, Melissa Hofmann, Albert Froneman, Hanneline A. Smit-Robinson, Antoinette Kotze 2019 National Zoological Garden South Africa National Biodiversity Institute

First Record Of White Stork In A Birdstrike In South Africa Above 3,300 M Agl, Desire Dalton, Marli De Bruyn, Monica Mwale, Kim Labuschagne, Melissa Hofmann, Albert Froneman, Hanneline A. Smit-Robinson, Antoinette Kotze

Human–Wildlife Interactions

Birdstrikes to aircrafts are increasing on an annual basis and pose significant aviation safety risks. Identification of the birds involved is key to developing mitigation strategies. Often the only information available to make identifications are feather and/or tissue samples. Relying on feathers alone to identify the bird species requires special expertise and access to museum collections for specimen comparisons. In 2017, feathers and tissue samples were recovered from the engine cowling of an airplane that had just landed at the Oliver Reginald (O. R.) Tambo international airport in South Africa after striking a bird at 3,353 m. To confirm the …


Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South 2019 Columbia University

Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South

Human–Wildlife Interactions

Effective management of rodent pests requires an ecological understanding of how they move through their environment and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space, but this field is often unapproachable to non-scientist pest management professionals (PMPs). In this …


The Increased Frequency Of Micronuclei Seen In Women With A History Of Childhood Sexual Abuse Reflects More Numerical Than Structural Acquired Chromosomal Events: A Discordant Identical Co-Twin Study, Kaitlyn M. Dochelli 2019 Virginia Commonwealth University

The Increased Frequency Of Micronuclei Seen In Women With A History Of Childhood Sexual Abuse Reflects More Numerical Than Structural Acquired Chromosomal Events: A Discordant Identical Co-Twin Study, Kaitlyn M. Dochelli

Theses and Dissertations

Childhood sexual abuse (CSA) is a stressful life experience with lasting/far-reaching health and psychopathological consequences. Our laboratory recently identified a significantly increased frequency of acquired chromosomal anomalies (assessed using the cytokinesis-blocked micronucleus assay) in adult female twins exposed to CSA when compared to their unexposed co-twin. The primary aim of this study was to evaluate potential mechanism(s) underlying the observed increases in levels of micronuclei in an expanded group of 90 female identical twins (61 CSA+ females and 29 CSA- females [including a total of 27 MZ co-twin pairs]) using fluorescence in situ hybridization (FISH) methodologies, with PNA probes specific …


Co-Localization Of Polycystic Ovary Syndrome Candidate Gene Products In Human Theca Cells Suggests Novel Signaling Pathways, Rewa M. Kulkarni 2019 Virginia Commonwealth University

Co-Localization Of Polycystic Ovary Syndrome Candidate Gene Products In Human Theca Cells Suggests Novel Signaling Pathways, Rewa M. Kulkarni

Theses and Dissertations

Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility and the most common endocrinopathy of women of reproductive age. Genome-wide association studies (GWAS) identified a number of loci associated PCOS in different ethnic populations, including women with Asian and European ancestry. Replication studies have confirmed some of these associations. Among the loci identified are those located near the LH receptor gene (LHCGR), a clathrin-binding protein gene (DENND1A) that also functions as a guanine nucleotide exchange factor, and the gene encoding RAB5B, a GTPase and protein involved in vesicular trafficking. The functional significance of one …


Genetic And Environmental Factors Influence Drosophila Ethanol Sedation, Rebecca E. Schmitt 2019 Virginia Commonwealth University

Genetic And Environmental Factors Influence Drosophila Ethanol Sedation, Rebecca E. Schmitt

Theses and Dissertations

Alcohol use disorder is a global health issue that affects a significant portion of the population, with affects including both negative mental and physical consequences. Currently, there are few treatment options available to those who suffer from alcohol use disorder, alcohol abuse, or alcohol dependence. Identifying candidate genes or environmental influences would therefore improve the means for possible treatments or identification of those people at risk for alcohol use disorder. Previous studies in humans have demonstrated an inverse association between initial sensitivity and risk for alcohol abuse. This connection allows investigators, and our laboratory, to investigate genetic and environmental factors …


Impact Of Industrial Biocides On Bacterial Isolates From Hydraulic Fracturing Produced Water, Waad Ahmed Aljohani 2019 Michigan Technological University

Impact Of Industrial Biocides On Bacterial Isolates From Hydraulic Fracturing Produced Water, Waad Ahmed Aljohani

Dissertations, Master's Theses and Master's Reports

Biocides are antimicrobial compounds that are designed to kill diverse groups of microbes in an untargeted fashion. Glutaraldehyde and DBNPA are commonly used to manage microbial growth in different industries. It is possible that biocide use may result in the development of bacterial resistance. However, resistance to DBNPA is believed to be limited under normal use conditions. We isolated a number of bacteria from produced water from a hydraulically fractured site in West Texas. We then tested the ability of these isolates to resist Glutaraldehyde and DBNPA. In this study, we found that these isolates have varying resistance to these …


Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex 2019 Missouri University of Science and Technology

Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex

Masters Theses

"The role of chromosomal rearrangements in reproductive isolation and introgression between species is poorly understood. In heterozygous form, rearrangements may directly interrupt meiotic progression leading to partial sterility/subfertility (underdominance) or may suppress local meiotic segregation (recombination suppression). Such unbalanced meiotic segregation may also result in reproductive isolation and play roles as a driving force of speciation. The objective of this study was to gain insight into the pattern of chromosomal rearrangements in two closely related killifish species in the genus Fundulus (F. notatus, and F. olivaceus) by constructing genetic linkage maps using high-resolution single nucleotide polymorphism (SNP) …


The Role Of Rmta In The Opportunistic Pathaogen Aspergillus Fumigatus, Roshan Dahal 2019 Northern Illinois University

The Role Of Rmta In The Opportunistic Pathaogen Aspergillus Fumigatus, Roshan Dahal

Graduate Research Theses & Dissertations

The fungus Aspergillus fumigatus is an opportunistic human pathogen capable of causing

a life-threatening systemic lung infection known as invasive aspergillosis among immune compromised

patients. This group includes individuals infected with HIV, people with hematological

malignancies, solid organ transplant patients, persons with genetic immunodeficiency and cancer

patient undergoing chemotherapy. Due to the medical relevance of this organism, it is imperative

to discover novel genetic elements to design antifungal drugs against A. fumigatus dissemination,

virulence and survival during human infection. Previously, the putative arginine methyltransferase

gene rmtA was characterized in the model organism Aspergillus nidulans and the opportunistic

plant pathogen Aspergillus …


A Pipeline For Exogenous Gene Expression And Biomass Analysis In Plants, Bijay Bisunke 2019 Eastern Illinois University

A Pipeline For Exogenous Gene Expression And Biomass Analysis In Plants, Bijay Bisunke

Masters Theses

Biological pretreatment of biomass is typically required for the production of liquid biofuels, which are viable alternatives to traditional fossil fuels. While traditional thermomechanical pretreatments are effective at helping to deconstruct lignocellulose, they are often expensive and tend to generate environmentally dangerous waste materials. An alternative to traditional pretreatment strategies is biological pretreatment, which has focused on lignocellulose-degrading organisms, such as white-rot fungi. While direct pretreatment of biomass with white-rot fungi has shown great promise, directly expressing functional white-rot fungi genes in plants (i.e. in planta expression) has the potential to be even more efficient because the biomass itself …


Study Of Genetic Regulators That Control Development And Secondary Metabolism In The Genus Aspergillus, Timothy Satterlee 2019 Northern Illinois University

Study Of Genetic Regulators That Control Development And Secondary Metabolism In The Genus Aspergillus, Timothy Satterlee

Graduate Research Theses & Dissertations

In this study, I investigated the role of two different regulatory genes in two different species of pathogenic fungi from the genus Aspergillus. The first study involves a transcriptome analysis of the epigenetic regulator rmtA in the plant pathogen Aspergillus flavus. A. flavus colonizes numerous oil seed crops such as corn, peanuts, treenuts and cotton worldwide, contaminating them with aflatoxins and other harmful potent toxins. Previously our lab characterized the gene rmtA, which encodes an arginine methyltransferase in A. flavus, and demonstrated its role as regulator of the expression of the aflatoxin gene cluster and concomitant synthesis of toxin. Furthermore, …


Genome-Wide Systems Genetics Of Alcohol Consumption And Dependence, Kristin Mignogna 2019 Virginia Commonwealth University

Genome-Wide Systems Genetics Of Alcohol Consumption And Dependence, Kristin Mignogna

Theses and Dissertations

Widely effective treatment for alcohol use disorder is not yet available, because the exact biological mechanisms that underlie this disorder are not completely understood. One way to gain a better understanding of these mechanisms is to examine the genetic frameworks that contribute to the risk for developing this disorder. This dissertation examines genetic association data in combination with gene expression networks in the brain to identify functional groups of genes associated with alcohol consumption and dependence.

The first study took advantage of the behavioral complexity of human samples, and experimental capabilities provided by mouse models, by co-analyzing gene expression networks …


Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney IV 2019 Virginia Commonwealth University

Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney Iv

Theses and Dissertations

Emplectonema gracile (Johnston 1837) is a hoplonemertean of marine intertidal hard-bottom communities and is distributed throughout the Northern Hemisphere. Although possessing a planktonic larval stage in its life history, the range of such cosmopolitan marine invertebrate species is often explained by cryptic speciation and anthropogenic transport. The purpose of this study is to test for possible cryptic species using mtDNA markers (COI and 16S rDNA) and to investigate population structure in E. gracile over a portion of its geographic range using mtDNA markers and ddRADseq nuclear SNP data. The results of both phylogenetic- and tree-based species delimitation revealed that E. …


Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer 2019 Georgia Southern University

Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer

College of Graduate Studies: Theses & Dissertations

The intestinal microbiome of mammals plays a significant role in host health and response to environmental stimuli and can include both beneficial native bacteria as well as parasitic worms. In this study, I examined the intestinal cestode and bacterial communities of two closely related species of shrew, Sorex monticola and Sorex cinereus, over a six month period in 2016. Specimens were collected approximately every three weeks from May to October from the Sangre de Cristo Mountains in Cowles, New Mexico. A total of 79 shrews were prepared with the gastrointestinal tracts removed and flash-frozen in liquid nitrogen. An additional …


Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin 2019 West Virginia University

Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Habitat creation is an important tool for conservation to counteract habitat loss and degradation. Vernal pools are susceptible to destruction due to limited detection, protection, and regulation. These wetlands provide fishless breeding habitat for many amphibian species including spotted salamanders (Ambystoma maculatum) in eastern North America. Determining whether created vernal pool habitat is successful is often determined by demographic data of colonizing populations. I suggest that hormone levels, population genetics, and disease prevalence can improve our understanding of population health in created habitat. The goal of this dissertation was to assess the health of spotted salamander larvae in …


Clonally Expanded Alpha-Chain T-Cell Receptor (Tcr) Transcripts Are Present In Aneurysmal Lesions Of Patients With Abdominal Aortic Aneurysm (Aaa), Song Lu, John V. White, Raquel I. Judy, Lisa L. Merritt, Wan Lu Lin, Xiaoying Zhang, Charalambos Solomides, Ifeyinwa Nwaneshiudu, John Gaughan, Dimitri S. Monos, Emilia L. Oleszak, Chris D. Platsoucas 2019 Old Dominion University

Clonally Expanded Alpha-Chain T-Cell Receptor (Tcr) Transcripts Are Present In Aneurysmal Lesions Of Patients With Abdominal Aortic Aneurysm (Aaa), Song Lu, John V. White, Raquel I. Judy, Lisa L. Merritt, Wan Lu Lin, Xiaoying Zhang, Charalambos Solomides, Ifeyinwa Nwaneshiudu, John Gaughan, Dimitri S. Monos, Emilia L. Oleszak, Chris D. Platsoucas

Biological Sciences Faculty Publications

Abdominal aortic aneurysm (AAA) is a life-threatening immunological disease responsible for 1 to 2% of all deaths in 65 year old or older individuals. Although mononuclear cell infiltrates have been demonstrated in AAA lesions and autoimmunity may be responsible for the initiation and account for the propagation of the disease, the information available about the pathogenesis of AAA is limited. To examine whether AAA lesions from patients with AAA contain clonally expanded α-chain TCR transcripts, we amplified by the non-palindromic adaptor-PCR (NPA-PCR)/Vα-specific PCR and/or the Vα-specific PCR these α-chain TCR transcripts. The amplified transcripts were cloned and sequenced. Substantial proportions …


Tiger Monitoring In Bhutan Using Non-Invasive Genetic Tools, Tashi Dhendup 2019 University of Montana

Tiger Monitoring In Bhutan Using Non-Invasive Genetic Tools, Tashi Dhendup

Graduate Student Theses, Dissertations, & Professional Papers

Large carnivores are one of the most threatened group of animals in the world. They suffer from prey depletion, persecution by humans, and habitat loss and fragmentation which are extensively driven by anthropogenic activities. One such species is the tiger Panthera tigris. Tigers are found in thirteen countries in Asia and are protected across the range; however, tiger numbers have declined as an after effect of habitat loss, prey depletion and poaching. Human-induced changes have reduced the tiger's historical range to about 7% in which a little more than 3900 tigers are found. Most of these individuals currently exist …


A Genome Wide Survey Of The Insertion Sequences In Halanaerobium Hydrogeniformans, A Haloalkaliphilic Anaerobic Bacterium, Kody Austin Bassett 2019 Missouri University of Science and Technology

A Genome Wide Survey Of The Insertion Sequences In Halanaerobium Hydrogeniformans, A Haloalkaliphilic Anaerobic Bacterium, Kody Austin Bassett

Masters Theses

"Insertion sequences (IS) are the smallest prokaryotic transposable elements. These mobile genes are highly diverse in size and structure, making them difficult to study. The transposition activity of insertion sequences has a significant role in evolution by enabling genomic plasticity via genome rearrangements. Insertion sequences are largely uncharacterized and thus methods to improve the ability to accurately identify, annotate, and infer genomic impact of insertion sequences is limited. A sequential set of methods using readily available genomic and bioinformatic tools was developed to accurately identify insertion sequences. This method was used to perform an entire genome survey of Halanaerobium hydrogeniformans …


การพัฒนาเทคนิค Recombinase Polymerase Amplification เพื่อตรวจหาเชื้อ Mycobacterium Avium Complex ด้วยตาเปล่า, เทิดศักดิ์ สุธาตุ 2019 คณะสหเวชศาสตร์

การพัฒนาเทคนิค Recombinase Polymerase Amplification เพื่อตรวจหาเชื้อ Mycobacterium Avium Complex ด้วยตาเปล่า, เทิดศักดิ์ สุธาตุ

Chulalongkorn University Theses and Dissertations (Chula ETD)

โรคติดเชื้อที่มีสาเหตุมาจาก Mycobacterium avium complex (MAC) มีอุบัติการณ์เพิ่มสูงขึ้นทั่วโลกรวมทั้งในประเทศไทย เนื่องมาจากการเพิ่มขึ้นของจำนวนผู้ป่วยที่มีภาวะภูมิคุ้มกันของร่ายกายต่ำ การวินิจฉัยเชื้อ MAC ในปัจจุบันที่อาศัยการเพาะเลี้ยงเชื้อและทดสอบปฏิกิริยาชีวเคมี นอกจากใช้ระยะเวลานานแล้ว ยังไม่สามารถจำแนกเชื้อได้ถึงระดับสปีชี่ส์ โดยเฉพาะอย่างยิ่งเชื้อ Mycobacterium avium และเชื้อ Mycobacterium intracellulare ซึ่งเป็นเชื้อ MAC ที่สำคัญและเพาะแยกได้บ่อยจากสิ่งส่งตรวจ ดังนั้นวัตถุประสงค์ของการศึกษาในครั้งนี้ คือการพัฒนาเทคนิค Recombinase Polymerase Amplification ร่วมกับการอ่านผลด้วยสี SYBR Green I (RPA/SYBR) ในการตรวจวินิจฉัยเชื้อ MAC ซึ่งอาศัยการเพิ่มปริมาณสารพันธุกรรมภายใต้อุณหภูมิคงที่ ร่วมกับไพรเมอร์ที่จำเพาะต่อเชื้อกลุ่ม MAC เชื้อ M. avium และเชื้อ M. intracellulare และอ่านผลที่เกิดขึ้นด้วยตาเปล่าได้ในทันทีภายหลังการเติมสี SYBR Green I ผลจากการทดสอบกับตัวอย่าง DNA ของเชื้อ MAC จำนวน 120 ตัวอย่าง พบว่าเทคนิค RPA/SYBR สามารถตรวจวินิจฉัยจำแนกสปีชี่ส์ของเชื้อ M. avium และเชื้อ M. intracellulare ได้อย่างมีประสิทธิภาพ โดยมีความไว 100% และความจำเพาะตั้งแต่ 80.7% ขึ้นไป ซึ่งจัดว่ามีความสอดคล้องในเกณฑ์ดีมากเมื่อเปรียบเทียบกับวิธีหาลำดับเบส (สถิติ Kappa มีค่าตั้งแต่ 0.801 ขึ้นไป) ในขณะที่เมื่อเปรียบเทียบกับเทคนิค PCR มีความไวตั้งแต่ 89.2% ขึ้นไปและความจำเพาะตั้งแต่ 97.5% ขึ้นไป และมีความสอดคล้องในเกณฑ์ดีมากเช่นเดียวกัน (สถิติ Kappa มีค่าตั้งแต่ 0.863 ขึ้นไป) นอกจากนี้เทคนิค RPA/SYBR ยังมีค่าความเข้มข้นของ DNA ต้นแบบน้อยที่สุดที่สามารถตรวจได้ เท่ากับ 1 ng/µl และไม่เกิดปฏิกิริยาข้ามกลุ่มกับเชื้อส่วนใหญ่ของ Mycobacterium แม้ว่าเทคนิค RPA/SYBR ที่ได้พัฒนาขึ้น มีขั้นตอนการทดสอบที่ทำง่าย …


ความหลากหลายทางพันธุกรรมของยีนบีเอซีอีวันและเอโปอี และระดับอะไมลอยด์เบต้าในเลือดของผู้ป่วยโรคไวรัสตับอักเสบบีเรื้อรังและตับอักเสบซีเรื้อรัง, ธัญรัตน์ ทองจรัส 2019 คณะสหเวชศาสตร์

ความหลากหลายทางพันธุกรรมของยีนบีเอซีอีวันและเอโปอี และระดับอะไมลอยด์เบต้าในเลือดของผู้ป่วยโรคไวรัสตับอักเสบบีเรื้อรังและตับอักเสบซีเรื้อรัง, ธัญรัตน์ ทองจรัส

Chulalongkorn University Theses and Dissertations (Chula ETD)

อะไมลอยด์เบต้า 42 (Aβ42) เป็นของเสียที่เกิดจากการย่อยอะไมลอยด์เบต้าพรีเคอเซอร์โปรตีน อาจเสี่ยงต่อการเกิดโรคอัลไซเมอร์เมื่อสะสมที่สมอง โดยมียีนบีเอซีอีวัน (BACE1) ควบคุมการสร้างเอนไซม์เบต้าซีครีเตส เพื่อย่อยอะไมลอยด์เบต้าพรีเคอเซอร์โปรตีน และมียีนเอโปอี (ApoE) เป็นยีนที่ถอดรหัสเป็น Apolipoprotein E ทำหน้าที่ขนส่งอะไมลอยด์เบต้าไปกำจัดที่ตับ คาดว่าการติดเชื้อไวรัสตับอักเสบเรื้อรังอาจส่งผลให้การกำจัดของเสียลดลงด้วย งานวิจัยนี้จึงมีวัตถุประสงค์เพื่อศึกษาระดับอะไมลอยด์เบต้า 42 ในเลือดด้วยหลักการ ELISA และศึกษาความหลากหลายทางพันธุกรรมของยีน BACE1 (rs638405) ด้วยหลักการ PCR-RFLP และยีน ApoE (rs429358 และ rs7412) ด้วยหลักการ real time PCR ในผู้ติดเชื้อไวรัสตับอักเสบบีเรื้อรัง (CHB, N=149) ซีเรื้อรัง (CHC, N=31) และคนปกติ (N=164) โดยเป็นผู้ติดเชื้อไวรัสตับอักเสบบีเรื้อรัง ซีเรื้อรังที่รักษา ณ โรงพยาบาลพระมงกุฎเกล้า และผู้บริจาคโลหิต ณ สถาบันพยาธิวิทยา ในช่วงเดือน สิงหาคม 2561 - มิถุนายน 2562 ผลการศึกษาพบว่าระดับอะไมลอยด์เบต้า 42 ในเลือดของผู้ป่วย CHB มีค่าสูงกว่าคนปกติ (CHB=46.86 pg/ml (N=22), CHC=43.27 pg/ml (N=15) และ คนปกติ =33.72 pg/ml (N=36), p-value=0.002) ข้อมูลจากกลุ่มตัวอย่างที่ตรวจวัดนี้มีจำนวนจำกัด จึงยังไม่สามารถนำไปอ้างอิงได้ นอกจากนี้ผู้วิจัยพบสัดส่วนของจีโนไทป์ของยีน BACE1 ในผู้ป่วย CHB (N=149), CHC (N=31) มีจีโนไทป์ C/G สูงกว่าในคนปกติ (N=164) (p-value = 0.044) และยีน ApoE ในผู้ป่วย CHB (N=149), CHC (N=31) มีจีโนไทป์ ε3ε4 สูงกว่าในคนปกติ (N=148) (p-value=0.001) …


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