Genetics and Genomics Commons^™

Genomic Epidemiology Of Clostridium Difficile Colonization And Transmission In An Intensive Care Unit Cohort, Brianne Ciferri

Dissertations and Theses

Abstract

Genomic epidemiology of Clostridium difficile colonization and transmission in an intensive care unit cohort

by Brianne Ciferri, MPH

Advisor: C. Mary Schooling, PhD

Introduction: Clostridiodes difficile (C. difficile) is a leading cause of healthcare associated infections (HAI) in the United States and responsible for an estimated incidence of 223,900 cases and 12,800 deaths per year^1,2. C. difficile can cause gastrointestinal illness with symptoms ranging from mild diarrheal illness to a life-threatening condition. C. difficile is an opportunistic pathogen in which spores can live in an undisturbed dormant state within the intestinal tract and become …

Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers by organ site with a 5-year survival rate of just 10.8%. This is largely because most patients do not experience symptoms until the disease has already metastasized. The best hope to cure PDAC is surgery, which can only be done with a curative intent at an early stage when the disease is localized. There are no reliable circulating, body-fluid-based biomarkers to detect early stage PDAC or its precursor lesions in a timely manner for effective surgical intervention. When potential PDAC precursor lesions, such as mucinous pancreatic cysts are found, there are …

Editorial For The Genetics Of Alzheimer’S Disease Special Issue: October 2021, Laura Ibanez, Justin B. Miller

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

Improved Radiation Expression Profiling In Blood By Sequential Application Of Sensitive And Specific Gene Signatures, Eliseos J. Mucaki, Ben C. Shirley, Peter K. Rogan

Biochemistry Publications

Purpose. Combinations of expressed genes can discriminate radiation-exposed from normal control blood samples by machine learning based signatures (with 8 to 20% misclassification rates). These signatures can quantify therapeutically-relevant as well as accidental radiation exposures. The prodromal symptoms of Acute Radiation Syndrome (ARS) overlap those present in Influenza and Dengue Fever infections. Surprisingly, these human radiation signatures misclassified gene expression profiles of virally infected samples as false positive exposures. The present study investigates these and other confounders, and then mitigates their impact on signature accuracy.

Methods. This study investigated recall by previous and novel radiation signatures independently derived …

An Enhancement To Cnn Approach With Synthesized Image Data For Disease Subtype Classification, Narider Pal Singh

Electronic Theses and Dissertations

The introduction of genetic testing has profoundly enhanced the prospects of early detection of diseases and techniques to suggest precision medicines. The subtyping of critical diseases has proven to be an essential part of the development of individualized therapies and has led to deeper insights into the heterogeneity of the disease. Studies suggest that variants in particular genes have significant effects on certain types of immune system cells and are also involved in the risk of certain critical illnesses like cancer. By analyzing the genetic sequence of a patient, disease types and subtypes can be predicted. Recent research work has …

Exome Sequence Association Study Of Levels And Longitudinal Change Of Cardiovascular Risk Factor Phenotypes In European Americans And African Americans From The Atherosclerosis Risk In Communities Study, Elena V Feofanova, Elise Lim, Han Chen, Minjae Lee, Ching-Ti Liu, L Adrienne Cupples, Eric Boerwinkle

Journal Articles

Cardiovascular disease (CVD) is responsible for 31% of all deaths worldwide. Among CVD risk factors are age, race, increased systolic blood pressure (BP), and dyslipidemia. Both BP and blood lipids levels change with age, with a dose-dependent relationship between the cumulative exposure to hyperlipidemia and the risk of CVD. We performed an exome sequence association study using longitudinal data with up to 7805 European Americans (EAs) and 3171 African Americans (AAs) from the Atherosclerosis Risk in Communities (ARIC) study. We assessed associations of common (minor allele frequency > 5%) nonsynonymous and splice-site variants and gene-based sets of rare variants with levels …

Higher Entropy Observed In Sars-Cov-2 Genomes From The First Covid-19 Wave In Pakistan, Najia Karim Ghanchi, Asghar Nasir, Kiran I. Masood, Syed Hani Abidi, Syed Faisal Mahmood, Akber Kanji, Safina Abdul Razzak, Waqasuddin Khan, Saba Shahid, Maliha Yameen, Ali Raza, Javaria Ashraf, Zeeshan Ansar Ahmed, Mohammad Buksh Dharejo, Nazneen Islam, Zahra Hasan, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background: We investigated the genome diversity of SARS-CoV-2 associated with the early COVID-19 period to investigate evolution of the virus in Pakistan.
Materials and methods: We studied ninety SARS-CoV-2 strains isolated between March and October 2020. Whole genome sequences from our laboratory and available genomes were used to investigate phylogeny, genetic variantion and mutation rates of SARS-CoV-2 strains in Pakistan. Site specific entropy analysis compared mutation rates between strains isolated before and after June 2020.
Results: In March, strains belonging to L, S, V and GH clades were observed but by October, only L and GH strains were present. The …

Exploring Β-Cell Function And Heterogeneity In Obese Sm/J Mice, Mario Alejandro Miranda

Arts & Sciences Electronic Theses and Dissertations

Pancreatic β-cells perform glucose-stimulated insulin secretion, a process required to maintain systemic glucose homeostasis. Obesity promotes glycemic and inflammatory stress, causing β-cell death and dysfunction, resulting in diabetes. Efforts to improve β-cell function in obesity have been hampered by observations that β-cells are highly heterogeneous, varying in morphology, function, and gene expression. There is great need to understand the breadth of β-cell heterogeneity in health and obesity to improve diabetic therapies.High fat-fed SM/J mice spontaneously transition from hyperglycemic-obese to normoglycemic-obese with age, providing a unique opportunity to study β-cell adaptation. Here, we show that as they resolve hyperglycemia, obese SM/J …

Discovery Of Sex Differences In Response To P53 Loss And Gain-Of-Function In Glioblastoma, Nathan Cuyle Rockwell

Arts & Sciences Electronic Theses and Dissertations

The tumor suppressor TP53 (p53) is the most frequently mutated gene in cancer and among the most mutated genes in brain cancer. Functionally, p53 is a transcription factor that, when activated by an array of stress stimuli, regulates a complex transcriptional program that contributes to a variety of antiproliferative pathways. The loss of p53 function (LOF), either through mutation, deletion, or inhibition by alterations in the proteins that regulate p53, removes an essential barrier to the unfettered proliferation and genomic instability that drive transformation. Unlike most tumor suppressors, many p53 mutations are missense mutations that lead to stable expression of …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

Genome-Wide Association Study Of Serum Metabolites In The African American Study Of Kidney Disease And Hypertension, Shengyuan Luo, Elena V Feofanova, Adrienne Tin, Sarah Tung, Eugene P Rhee, Josef Coresh, Dan E Arking, Aditya Surapaneni, Pascal Schlosser, Yong Li, Anna Köttgen, Bing Yu, Morgan E Grams

Journal Articles

The genome-wide association study (GWAS) is a powerful means to study genetic determinants of disease traits and generate insights into disease pathophysiology. to date, few GWAS of circulating metabolite levels have been performed in African Americans with chronic kidney disease. Hypothesizing that novel genetic-metabolite associations may be identified in a unique population of African Americans with a lower glomerular filtration rate (GFR), we conducted a GWAS of 652 serum metabolites in 619 participants (mean measured glomerular filtration rate 45 mL/min/1.73m

The Role Of Interspecies Recombination In The Evolution Of Antibiotic-Resistant Pneumococci, Joshua C. D'Aeth, Mark Pg Van Der Linden, Lesley Mcgee, Herminia De Lencastre, Paul Turner, Jae-Hoon Song, Stephanie W. Lo, Rebecca A. Gladstone, Gps Consortium, Sadia Shakoor

Department of Pathology and Laboratory Medicine

Multidrug-resistant Streptococcus pneumoniae emerge through the modification of core genome loci by interspecies homologous recombinations, and acquisition of gene cassettes. Both occurred in the otherwise contrasting histories of the antibiotic-resistant S. pneumoniae lineages PMEN3 and PMEN9. A single PMEN3 clade spread globally, evading vaccine-induced immunity through frequent serotype switching, whereas locally circulating PMEN9 clades independently gained resistance. Both lineages repeatedly integrated Tn916-type and Tn1207.1-type elements, conferring tetracycline and macrolide resistance, respectively, through homologous recombination importing sequences originating in other species. A species-wide dataset found over 100 instances of such interspecific acquisitions of resistance cassettes and flanking …

Novel Scalable And Simplified System To Generate Microglia-Containing Cerebral Organoids From Human Induced Pluripotent Stem Cells, Brittany Bodnar, Yongang Zhang, Jinbiao Liu, Yuan Lin, Peng Wang, Zhengyu Wei, Sami Saribas, Yuanjun Zhu, Fang Li, Xu Wang, Wenli Yang, Qingsheng Li, Wen-Zhe Ho, Wenhui Hu

Nebraska Center for Virology: Faculty Publications

Human cerebral organoid (CO) is a three-dimensional (3D) cell culture system that recapitulates the developing human brain. While CO has proved an invaluable tool for studying neurological disorders in a more clinically relevant matter, there have still been several shortcomings including CO variability and reproducibility as well as lack of or underrepresentation of certain cell types typically found in the brain. As the technology to generate COs has continued to improve, more efficient and streamlined protocols have addressed some of these issues. Here we present a novel scalable and simplified system to generate microglia-containing CO (MCO). We characterize the cell …

A Screen For Sleep And Starvation Resistance Identifies A Wake-Promoting Role For The Auxiliary Channel Unc79, Kazuma Murakami, Justin Palermo, Bethany A. Stanhope, Allen G. Gibbs, Alex C. Keene

Life Sciences Faculty Research

The regulation of sleep and metabolism are highly interconnected, and dysregulation of sleep is linked to metabolic diseases that include obesity, diabetes, and heart disease. Furthermore, both acute and long-term changes in diet potently impact sleep duration and quality. To identify novel factors that modulate interactions between sleep and metabolic state, we performed a genetic screen for their roles in regulating sleep duration, starvation resistance, and starvation-dependent modulation of sleep. This screen identified a number of genes with potential roles in regulating sleep, metabolism, or both processes. One such gene encodes the auxiliary ion channel UNC79, which was implicated in …

Full Issue: The International Undergraduate Journal Of Health Sciences, Volume 1, Issue 1, June 2021

International Undergraduate Journal of Health Sciences

The full June 2021 issue (Volume 1, Issue 1) of the International Undergraduate Journal of Health Sciences

Draft Genome Sequences Of 13 Vibrio Cholerae Strains From The Rio Grande Delta, Jeffrey W. Turner, Jorge Duran-Gonzalez, David A. Laughlin, Daniel Unterweger, David Silva, Boris Ermolinsky, Stefan Pukatzki, Daniele Provenzano

Publications and Research

Vibrio cholerae is the etiologic agent of cholera, an acute and often fatal diarrheal disease that affects millions globally. We report the draft genome sequences of 13 non-O1/O139 V. cholerae strains isolated from the Rio Grande Delta in Texas. These genomes will aid future analyses of environmental serovars.

Impact Of Intratumor Heterogeneity And The Tumor Microenvironment In Shaping Tumor Evolution And Response To Therapy, Akash Mitra

Dissertations & Theses (Open Access)

Intratumor heterogeneity (ITH) is a crucial challenge in cancer treatment. The genotypic and phenotypic heterogeneity underlying diverse cancer types leads to subclonal variation, which may result in mixed or failed response to therapy. The heterogeneity at the tumor level, along with the tumor microenvironment (TME), often shapes tumor evolution and ultimately clinical outcome. Given that modern treatment paradigms increasingly expose patients with metastatic disease to multiple treatment modalities through the course of their disease, there exists a need to characterize robust and predictive biomarkers of response to therapy. In order to accurately characterize tumor evolution, we need to account for …

Transcriptional Control Of Dendritic Cell Function And Development, David Alexander Anderson Iii

Arts & Sciences Electronic Theses and Dissertations

Dendritic cells (DCs) are innate immune cells of the myeloid lineage that are specialized at pathogen recognition, cytokine production, and antigen presentation. Their functions and developmental pathways are largely conserved between mice and humans and mice. The DC lineage is composed of two major subsets, known as plasmacytoid DCs (pDCs) and classical DCs (cDCs). Research conducted to date suggests that the function of pDCs, limited to viral antigen recognition and type I interferon production, can be compensated by other immune cell lineages. On the other hand, there is a consensus that diversified subsets cDCs in mice and humans are essential …

Germline Variants Associated With Cancer Predisposition And Bone Marrow Failure Are Common In Kmt2a-R Infant Acute Lymphoblastic Leukemia Patients, Sarah E. Mc Dermott

Research Days

Background: Infant acute lymphoblastic leukemia (ALL), is a particularly aggressive subtype of leukemia with an early onset and unfavorable clinical outcome. Most (~70%) cases of infant ALL involve chromosomal rearrangement of KMT2A (KMT2A- r) on chromosome 11q23, the strongest independent predictor of a poor prognosis. To date, genomics studies have consistently demonstrated KMT2A-r infant ALL to have a strikingly silent landscape of DNA mutations. Germline mutations in cancer predisposition genes are found in 8.6% of pediatric malignancies and 4.4% of pediatric leukemias, compared to 1.1% in persons in the 1000 Genomes Project.

Objectives/Goal: We hypothesized that germline variants may contribute …

Genome Sequence Of A Virulent African Swine Fever Virus Isolated In 2020 From A Domestic Pig In Northern Vietnam, Quang Lam Truong, Thi Lan Nguyen, Thi Hoa Nguyen, Jishu Shi, Hiep Lai Xuan Vu, Thi Lan Huong Lai, Van Giap Nguyen

Nebraska Center for Virology: Faculty Publications

This study reports the genome sequence of an isolated African swine fever (ASF) virus (VNUA-ASFV-05L1/HaNam) obtained at the fourth passage on pulmonary alveolar macrophages. The virus was isolated during a typical acute ASF outbreak in pigs in a northern province of Vietnam in 2020.

The Immune Microenvironment And Relation To Outcome In Patients With Advanced Breast Cancer Treated With Docetaxel With Or Without Gemcitabine, Elisabeth S. Stovgaard, Karama Asleh, Nazia Riaz, Samuel Leung, Dongxia Gao, Lise B. Nielsen, Anne-Vibeke Lænkholm, Eva Balslev, Maj-Britt Jensen, Dorte Nielsen, Torsten O. Nielsen

Centre for Regenerative Medicine & Stem Cell Research

Preclinical studies suggest that some effects of conventional chemotherapy, and in particular, gemcitabine, are mediated through enhanced antitumor immune responses. The objective of this study was to use material from a randomized clinical trial to evaluate whether patients with preexisting immune infiltrates responded better to treatment with gemcitabine + docetaxel (GD) compared to docetaxel alone. Formalin fixed, paraffin-embedded breast cancer tissues from SBG0102 phase 3 trial patients randomly assigned to treatment with GD or docetaxel were used. Immunohistochemical staining for CD8, FOXP3, LAG3, PD-1, PD-L1 and CD163 was performed. Tumor infiltrating lymphocytes (TILs) and tumor associated macrophages were evaluated. Prespecified …

Mucin And Splice Variant Profiles Of Pancreatic Adenocarcinoma Predict Patient Survival And Subtyping, Christopher M. Thompson

Theses & Dissertations

PDAC is a pancreatic epithelial malignancy and demonstrates aggressive progression and bleak patient prognosis. Despite decades of research, the evolution of novel diagnostics and intervention modalities for PDAC is stagnant. This dissertation explores the characteristic aberrant and elevated expression of mucins in PDAC. Beginning with the hypothesis that mucins are associated with disease aggressiveness, analysis of PDAC patient survival in TCGA revealed no associations between single mucin expression and patient survival. This led to the underlying issue of PDAC tumor cellularity since this disease demonstrates variability in the proportion of cancer cells within the tumor. Tumor purity assessed with the …

Codon Bias Can Determine Sorting Of A Potassium Channel Protein, Anja J. Engel, Marina Kithil, Markus Langhans, Oliver Rauh, Matea Cartolano, James L. Van Etten, Anna Moroni, Gerhard Thiel

Nebraska Center for Virology: Faculty Publications

Due to the redundancy of the genetic code most amino acids are encoded by multiple synonymous codons. It has been proposed that a biased frequency of synonymous codons can affect the function of proteins by modulating distinct steps in transcription, translation and folding. Here, we use two similar prototype K⁺ channels as model systems to examine whether codon choice has an impact on protein sorting. By monitoring transient expression of GFP-tagged channels in mammalian cells, we find that one of the two channels is sorted in a codon and cell cycle-dependent manner either to mitochondria or the secretory pathway. …

Biases And Blind-Spots In Genome-Wide Crispr-Cas9 Knockout Screens, Merve Dede

Dissertations & Theses (Open Access)

Adaptation of the bacterial CRISPR-Cas9 system to mammalian cells revolutionized the field of functional genomics, enabling genome-scale genetic perturbations to study essential genes, whose loss of function results in a severe fitness defect. There are two types of essential genes in a cell. Core essential genes are absolutely required for growth and proliferation in every cell type. On the other hand, context-dependent essential genes become essential in an environmental or genetic context. The concept of context-dependent gene essentiality is particularly important in cancer, since killing cancer cells selectively without harming surrounding healthy tissue remains a major challenge. The toxicity of …

Carrier Screening For Women Undergoing Elective Oocyte Cryopreservation (Eoc): A Look At Practice Among Reproductive Endocrinologists At An Academic Fertility Clinic, Melissa Manuelli

Human Genetics Theses

Elective oocyte cryopreservation (EOC) is a process involving freezing and banking oocytes with the intention to be used in the future for pregnancy. Cryopreserving oocytes allows women to enhance their reproductive autonomy by reducing the effects of age-relatedfertility decline. Similarly, expanded carrier screening (ECS) completed prior to conception allows women to consider their full range of reproductive options including in-vitro fertilization (IVF) with preimplantation genetic testing (PGT), use of donor gametes, and prenatal testing and diagnosis. In this retrospective chart review, we examine carrier screening practices for 106 EOC patients, and an age-matched control group of 106 IVF patients who …

Utilization And Perceived Value Of Genetic Counselors Within U.S. Hemophilia Treatment Centers, Caylynn Carls

Human Genetics Theses

Rapid advancement of molecular genetics has transformed the diagnosis, treatment, and management of individuals with hereditary bleeding disorders. To provide effective, up-to-date genetic counseling, navigate the complexity of these conditions, and select appropriate molecular testing, genetics expertise is required. This study assessed the provision of genetic counseling services, the involvement of genetic counselors (GCs), and the perceived value of GCs within hemophilia treatment centers (HTCs) in the United States. A survey was emailed to 396 HTC providers. 115 responses were received, representing 68 of 149 U.S. HTCs (45.6% HTC participation rate). Responses were stratified by level of GC engagement. Although …

Importance Of Understanding Genetic Predisposition, Andrew Carter

Thinking Matters Symposium

Hypersensitivity reactions can be sudden and are often fatal. Many of these reactions occur as a result of allergies to prescribed medication. Adverse drug reactions or (ADR’s) were show in a recent study to affect over 6% of hospitalized patients and resulted in over 100,000 deaths a year in the US alone. This poster will review the importance of understanding genetic predisposition, through articles about possible genetic causes of allergies to penicillin and other beta-lactams. Changes in a specific HLA gene located on chromosome 6 showed a correlation to penicillin reactions in over 600,000 participants. Another study found a conclusive …

Identification Of A Chlorovirus Pbcv-1 Protein Involved In Degrading The Host Cell Wall During Virus Infection, Irina V. Agarkova, Leslie C. Lane, David D. Dunigan, Cristian F. Quispe, Garry A. Duncan, Elad Milrot, Abraham Minsky, Ahmed Esmael, Jayadri S. Ghosh, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Chloroviruses are unusual among viruses infecting eukaryotic organisms in that they must, like bacteriophages, penetrate a rigid cell wall to initiate infection. Chlorovirus PBCV-1 infects its host, Chlorella variabilis NC64A by specifically binding to and degrading the cell wall of the host at the point of contact by a virus-packaged enzyme(s). However, PBCV-1 does not use any of the five previously characterized virus-encoded polysaccharide degrading enzymes to digest the Chlorella host cell wall during virus entry because none of the enzymes are packaged in the virion. A search for another PBCV-1-encoded and virion-associated protein identified protein A561L. The fourth domain …

An Ensemble Of The Icluster Method To Analyze Longitudinal Lncrna Expression Data For Psoriasis Patients, Suyan Tian, Chi Wang

Internal Medicine Faculty Publications

BACKGROUND: Psoriasis is an immune-mediated, inflammatory disorder of the skin with chronic inflammation and hyper-proliferation of the epidermis. Since psoriasis has genetic components and the diseased tissue of psoriasis is very easily accessible, it is natural to use high-throughput technologies to characterize psoriasis and thus seek targeted therapies. Transcriptional profiles change correspondingly after an intervention. Unlike cross-sectional gene expression data, longitudinal gene expression data can capture the dynamic changes and thus facilitate causal inference.

METHODS: Using the iCluster method as a building block, an ensemble method was proposed and applied to a longitudinal gene expression dataset for psoriasis, with the …

Genetic Discovery And Risk Characterization In Type 2 Diabetes Across Diverse Populations, Linda M Polfus, Burcu F Darst, Heather Highland, Xin Sheng, Maggie C Y Ng, Jennifer E Below, Lauren Petty, Stephanie Bien, Xueling Sim, Wei Wang, Pierre Fontanillas, Yesha Patel, Michael Preuss, Claudia Schurmann, Zhaohui Du, Yingchang Lu, Suhn K Rhie, Joseph M Mercader, Teresa Tusie-Luna, Clicerio González-Villalpando, Lorena Orozco, Cassandra N Spracklen, Brian E Cade, Richard A Jensen, Meng Sun, Yoonjung Yoonie Joo, Ping An, Lisa R Yanek, Lawrence F Bielak, Salman Tajuddin, Aude Nicolas, Guanjie Chen, Laura Raffield, Xiuqing Guo, Wei-Min Chen, Girish N Nadkarni, Mariaelisa Graff, Ran Tao, James S Pankow, Martha Daviglus, Qibin Qi, Eric A Boerwinkle, Simin Liu, Lawrence S Phillips, Ulrike Peters, Chris Carlson, Lynne R Wikens, Loic Le Marchand, Kari E North, Steven Buyske, Charles Kooperberg, Ruth J F Loos, Daniel O Stram, Christopher A Haiman

Journal Articles

Genomic discovery and characterization of risk loci for type 2 diabetes (T2D) have been conducted primarily in individuals of European ancestry. We conducted a multiethnic genome-wide association study of T2D among 53,102 cases and 193,679 control subjects from African, Hispanic, Asian, Native Hawaiian, and European population groups in the Population Architecture Genomics and Epidemiology (PAGE) and Diabetes Genetics Replication and Meta-analysis (DIAGRAM) Consortia. In individuals of African ancestry, we discovered a risk variant in the