Medical Microbiology Commons^™

Short Signature Rpob Gene Sequence To Differentiate Species In Mycobacterium Abscessus Group, Jian R Bao, Kileen L Shier, Ronald N Master, Robert S Jones, Richard B Clark

Faculty, Staff and Student Publications

Mycobacterium abscessus group (MAG) are rapidly growing acid-fast bacteria that consist of three closely related species: M. abscessus (Ma), M. bolletii (Mb), and M. massiliense (Mm). Differentiation of these species can be difficult but is increasingly requested owing to recent infectious outbreaks and their differential drug resistance. We developed a novel and rapid pyrosequencing method using short signature sequences (35 to 45 bp) at a hypervariable site in the rpoB gene to differentiate the three MAG species, along with M. chelonae (Mc), and M. immunogenum (Mi). This method was evaluated …

Phage Resistance Accompanies Reduced Fitness Of Uropathogenic Escherichia Coli In The Urinary Environment, Jacob J Zulk, Justin R Clark, Samantha Ottinger, Mallory B Ballard, Marlyd E Mejia, Vicki Mercado-Evans, Emmaline R Heckmann, Belkys C Sanchez, Barbara W Trautner, Anthony W Maresso, Kathryn A Patras

Faculty, Staff and Students Publications

Urinary tract infection (UTI) is among the most common infections treated worldwide each year and is caused primarily by uropathogenic Escherichia coli (UPEC). Rising rates of antibiotic resistance among uropathogens have spurred a consideration of alternative treatment strategies, such as bacteriophage (phage) therapy; however, phage-bacterial interactions within the urinary environment are poorly defined. Here, we assess the activity of two phages, namely, HP3 and ES17, against clinical UPEC isolates using in vitro and in vivo models of UTI. In both bacteriologic medium and pooled human urine, we identified phage resistance arising within the first 6 to 8 h of coincubation. …

Integrated Relationship Of Nasopharyngeal Airway Host Response And Microbiome Associates With Bronchiolitis Severity, Michimasa Fujiogi, Yoshihiko Raita, Marcos Pérez-Losada, Robert J Freishtat, Juan C Celedón, Jonathan M Mansbach, Pedro A Piedra, Zhaozhong Zhu, Carlos A Camargo, Kohei Hasegawa

Faculty, Staff and Students Publications

Bronchiolitis is a leading cause of infant hospitalizations but its immunopathology remains poorly understood. Here we present data from 244 infants hospitalized with bronchiolitis in a multicenter prospective study, assessing the host response (transcriptome), microbial composition, and microbial function (metatranscriptome) in the nasopharyngeal airway, and associate them with disease severity. We investigate individual associations with disease severity identify host response, microbial taxonomical, and microbial functional modules by network analyses. We also determine the integrated relationship of these modules with severity. Several modules are significantly associated with risks of positive pressure ventilation use, including the host-type I interferon, neutrophil/interleukin-1, T cell …

The Roles Of Gut Microbiome And Plasma Metabolites In The Associations Between Abo Blood Groups And Insulin Homeostasis: The Microbiome And Insulin Longitudinal Evaluation Study (Miles), Ruifang Li-Gao, Kirk Grubbs, Alain G Bertoni, Kristi L Hoffman, Joseph F Petrosino, Gautam Ramesh, Martin Wu, Jerome I Rotter, Yii-Der Ida Chen, Anne M Evans, Richard J Robinson, Laura Sommerville, Dennis Mook-Kanamori, Mark O Goodarzi, Gregory A Michelotti, Patricia A Sheridan

Faculty, Staff and Students Publications

Non-O blood groups are associated with decreased insulin sensitivity and risk of type 2 diabetes. A recent study pinpointed the associations between ABO blood groups and gut microbiome, which may serve as potential mediators for the observed increased disease risks. We aimed to characterize associations between ABO haplotypes and insulin-related traits as well as potential mediating pathways. We assessed insulin homeostasis in African Americans (AAs; n = 109) and non-Hispanic whites (n = 210) from the Microbiome and Insulin Longitudinal Evaluation Study. The ABO haplotype was determined by six SNPs located in the ABO gene. Based on prior knowledge, …

The Need For Sexual Health Clinics, Their Future Role, And Contribution To Public Health, Meena S. Ramchandani, Christopher Bourne, Lindley A. Barbee, Elske Hoornenborg, Preeti Pathela, Stephanie N. Taylor, Henry De Vries

School of Medicine Faculty Publications

Specialised sexual health clinics (SHCs) play an important role in addressing the staggering rates of STIs seen in many high-income nations. Despite increasing healthcare coverage in the US and nationalised health care in some countries, there is a continued need for SHCs to meet the needs of patients and the community, especially for high-priority populations: those at high risk of STI acquisition and/or groups historically marginalised and underserved in the traditional healthcare system. We need to mobilise resources to support a stronger clinical infrastructure in specialised SHCs. This review describes the importance of SHCs, their future role, and some of …

Gray And White Matter Abnormality In Patients With T2dm-Related Cognitive Dysfunction: A Systemic Review And Meta-Analysis, Teng Ma, Ze-Yang Li, Ying Yu, Bo Hu, Yu Han, Min-Hua Ni, Yu-Xiang Huang, Hao-Han Chen, Wen Wang, Lin-Feng Yan, Guang-Bin Cui

Faculty, Staff and Student Publications

Aims/hypothesis

Brain structure abnormality in patients with type 2 diabetes mellitus (T2DM)-related cognitive dysfunction (T2DM-CD) has been reported for decades in magnetic resonance imaging (MRI) studies. However, the reliable results were still unclear. This study aimed to make a systemic review and meta-analysis to find the significant and consistent gray matter (GM) and white matter (WM) alterations in patients with T2DM-CD by comparing with the healthy controls (HCs).

Methods

Published studies were systemically searched from PubMed, MEDLINE, Cochrane Library and Web of Science databases updated to November 14, 2021. Studies reporting abnormal GM or WM between patients with T2DM-CD and …

An Auto-Inhibited State Of Protein Kinase G And Implications For Selective Activation, Rajesh Sharma, Jeong Joo Kim, Liying Qin, Philipp Henning, Madoka Akimoto, Bryan Vanschouwen, Gundeep Kaur, Banumathi Sankaran, Kevin R Mackenzie, Giuseppe Melacini, Darren E Casteel, Friedrich W Herberg, Choel Kim

Faculty, Staff and Students Publications

Cyclic GMP-dependent protein kinases (PKGs) are key mediators of the nitric oxide/cyclic guanosine monophosphate (cGMP) signaling pathway that regulates biological functions as diverse as smooth muscle contraction, cardiac function, and axon guidance. Understanding how cGMP differentially triggers mammalian PKG isoforms could lead to new therapeutics that inhibit or activate PKGs, complementing drugs that target nitric oxide synthases and cyclic nucleotide phosphodiesterases in this signaling axis. Alternate splicing of PRKG1 transcripts confers distinct leucine zippers, linkers, and auto-inhibitory (AI) pseudo-substrate sequences to PKG Iα and Iβ that result in isoform-specific activation properties, but the mechanism of enzyme auto-inhibition and its alleviation …

Microbiome Dynamics During Chemoradiation Therapy For Anal Cancer, Daniel Lin, Molly B. El Alam, Joseph Abi Jaoude, Ramez Kouzy, Jae L. Phan, Jacob H. Elnaggar, Brianna Resendiz, Andrea Y. Delgado Medrano, Erica J. Lynn, Nicholas D. Nguyen, Sonal S. Noticewala, Geena G. Mathew, Emma B. Holliday, Bruce D. Minsky, Prajnan Das, Van K. Morris, Cathy Eng, Melissa P. Mezzari, Joseph F. Petrosino, Nadim J. Ajami, Ann H. Klopp, Cullen M. Taniguchi, Lauren E. Colbert

School of Graduate Studies Faculty Publications

Purpose: Patients with localized squamous cell carcinoma of the anus (SCCA) who experience treatment toxicity or recurrences have few therapeutic options. Investigation into the microbiome's influence on treatment toxicity and its potential use as a predictive biomarker could improve these patients’ outcomes. Our study presents the first longitudinal characterization of the SCCA tumor microbiome and its associations with treatment-related toxicities. Methods and Materials: This prospective cohort study included patients with nonmetastatic SCCA receiving standard-of-care chemoradiation therapy. Anorectal swabs of the tumor site were collected before, during, and after treatment. Patient-reported quality-of-life metrics were collected at similar time points. 16S rRNA …

Homeostasis Of Cell Wall Integrity Pathway Phosphorylation Is Required For The Growth And Pathogenicity Of Magnaporthe Oryzae, Yongchao Cai, Xinyu Liu, Lingbo Shen, Nian Wang, Yangjie He, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Graduate Studies Faculty Publications

The cell wall provides a crucial barrier to stress imposed by the external environment. In the rice blast fungus Magnaporthe oryzae, this stress response is mediated by the cell wall integrity (CWI) pathway, consisting of a well-characterized protein phosphorylation cascade. However, other regulators that maintain CWI phosphorylation homeostasis, such as protein phosphatases (PPases), remain unclear. Here, we identified two PPases, MoPtc1 and MoPtc2, that function as negative regulators of the CWI pathway. MoPtc1 and MoPtc2 interact with MoMkk1, one of the key components of the CWI pathway, and are crucial for the vegetative growth, conidial formation, and virulence of M. …

Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis

Graduate Theses and Dissertations (2019 - present)

The genus Rickettsia is comprised of Gram-negative, obligate intracellular bacteria that are spread by hematophagous arthropods. Elucidating the factors conferring rickettsial virulence has perplexed investigators for decades, complicated by the lack of efficient genetic tools necessary to uncover rickettsial- and vector-specific factors contributing to persistence. The advent of transposon mutagenesis has enabled the field to make vast developments in uncovering novel rickettsial mechanisms utilized in various host backgrounds. Thus, the aim of this study was to generate Rickettsia felis transposon mutants and characterize novel phenotypes associated with genetic disruption in an arthropod background. Distribution of rickettsiae is reliant on the …

Changes Of Brain Function In Patients With Type 2 Diabetes Mellitus Measured By Different Analysis Methods: A New Coordinate-Based Meta-Analysis Of Neuroimaging, Ze-Yang Li, Teng Ma, Ying Yu, Bo Hu, Yu Han, Hao Xie, Min-Hua Ni, Zhu-Hong Chen, Yang-Ming Zhang, Yu-Xiang Huang, Wen-Hua Li, Wen Wang, Lin-Feng Yan, Guang-Bin Cui

Faculty, Staff and Student Publications

OBJECTIVE: Neuroimaging meta-analysis identified abnormal neural activity alterations in patients with type 2 diabetes mellitus (T2DM), but there was no consistency or heterogeneity analysis between different brain imaging processing strategies. The aim of this meta-analysis was to determine consistent changes of regional brain functions in T2DM

METHODS: Since the indicators obtained using varied post-processing methods reflect different neurophysiological and pathological characteristics, we further conducted a coordinate-based meta-analysis (CBMA) of the two categories of neuroimaging literature, which were grouped according to similar data processing methods: one group included regional homogeneity (ReHo), independent component analysis (ICA), and degree centrality (DC) studies, while …

Cyclic Di-Gmp Regulates Motility, Biofilm Formation, And Desiccation Tolerance In Acinetobacter Baumannii, Garrett Reynolds

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections necessitating the discovery of novel treatments. A bacterial second messenger, cyclic diguanosine monophosphate (cyclic di-GMP), can regulate various persistence factors that are potentially advantageous for survival in hospital environments. Cyclic di-GMP–modulating enzymes and cyclic di-GMP–binding effectors predictively are encoded in the Acinetobacter baumannii genome. I hypothesized that cyclic di-GMP controls motility, biofilm formation, and desiccation tolerance in Acinetobacter baumannii. Disrupting cyclic di-GMP–modulating enzymes or cyclic di-GMP–binding effectors should alter the regulatory effectiveness of these phenotypes. I tested the multidrug-resistant isolate Acinetobacter baumannii strain AB5075 and identified several transposon …

Exome Sequencing Identifies Genetic Variants In Anophthalmia And Microphthalmia, Jingjing Li, Wei Yang, Yuejun Jessie Wang, Chen Ma, Cynthia J Curry, Daniel Mcgoldrick, Deborah A Nickerson, Jessica X Chong, Elizabeth E Blue, James C Mullikin, Jennita Reefhuis, Wendy N Nembhard, Paul A Romitti, Martha M Werler, Marilyn L Browne, Andrew F Olshan, Richard H Finnell, Marcia L Feldkamp, Faith Pangilinan, Lynn M Almli, Mike J Bamshad, Lawrence C Brody, Mary M Jenkins, Gary M Shaw, University Of Washington Center For Mendelian Genomics, Nisc Comparative Sequencing Program, National Birth Defects Prevention Study

Faculty, Staff and Students Publications

Anophthalmia and microphthalmia (A/M) are rare birth defects affecting up to 2 per 10,000 live births. These conditions are manifested by the absence of an eye or reduced eye volumes within the orbit leading to vision loss. Although clinical case series suggest a strong genetic component in A/M, few systematic investigations have been conducted on potential genetic contributions owing to low population prevalence. To overcome this challenge, we utilized DNA samples and data collected as part of the National Birth Defects Prevention Study (NBDPS). The NBDPS employed multi-center ascertainment of infants affected by A/M. We performed exome sequencing on 67 …

Salivary Biomarker Evaluation Of Chronic Pancreatitis Patients Reveals Alterations In Human Proteins, Cytokines, Prostaglandin E2 Levels, And Bacterial Diversity, Richard T Waldron, Elaina K Jones, Vincent I Anani, Jolaine M Hines, Jing Zhao, Aurelia Lugea, Marcio A Diniz, Sungjin Kim, Aida Habtezion, Kristi L Hoffman, Joseph F Petrosino, William E Fisher, Liang Li, Ryan J Lennon, Ravinder Jit Singh, Santhi Swaroop Vege, Stephen J Pandol, Mark D Topazian

Faculty, Staff and Students Publications

OBJECTIVES: Chronic pancreatitis (CP) is a chronic fibroinflammatory condition of the pancreas difficult to diagnose in early stages. Novel biomarkers useful to facilitate early diagnosis or treatment responses may be found in biofluids. Although saliva can be easily and noninvasively collected from patients, useful salivary biomarkers from CP patients have not yet been identified.

METHODS: Here, we analyzed the proteome by quantitative proteomics, cytokine/chemokine levels by Luminex analysis, prostaglandin E2 (PGE2) levels by a mass spectrometry-based assay, and bacterial species diversity by 16S ribosomal ribonucleic acid sequencing in saliva samples from confirmed CP patients and healthy controls.

RESULTS: Our results …

Patients With Lung Cancer Of Different Racial Backgrounds Harbor Distinct Immune Cell Profiles, Yitian Xu, Licheng Zhang, Jose Thaiparambil, Sunny Mai, Dimuthu Nuwan Perera, Jilu Zhang, Ping-Ying Pan, Cristian Coarfa, Kenneth Ramos, Shu-Hsia Chen, Randa El-Zein

Faculty, Staff and Students Publications

UNLABELLED: Tumors accumulated with infiltrated immune cells (hot tumors) have a higher response rate to immune checkpoint blockade, when compared with those with minimal T-cell infiltration (cold tumors). We report here that patients with lung cancer with different racial backgrounds harbored distinct immune cell profiles in the tumor microenvironment. Compared with African Americans (AA), Caucasian Americans (CA) exhibited increased immune cell infiltration and vasculature, and increased survival. Changes of survival and immune profile were most pronounced among active smokers and nonsmokers, compared with former smokers and total patients. Neighborhood analysis showed that immune cells accumulated around cancer cells in CAs …

Early Growth Response 1 Transcription Factor Is Essential For The Pathogenic Properties Of Human Endometriotic Epithelial Cells, Vineet K Maurya, Maria M Szwarc, Rodrigo Fernandez-Valdivia, David M Lonard, Song Yong, Niraj Joshi, Asgerally T Fazleabas, John P Lydon

Faculty, Staff and Students Publications

Although a non-malignant gynecological disorder, endometriosis displays some pathogenic features of malignancy, such as cell proliferation, migration, invasion and adaptation to hypoxia. Current treatments of endometriosis include pharmacotherapy and/or surgery, which are of limited efficacy and often associated with adverse side effects. Therefore, to develop more effective therapies to treat this disease, a broader understanding of the underlying molecular mechanisms that underpin endometriosis needs to be attained. Using immortalized human endometriotic epithelial and stromal cell lines, we demonstrate that the early growth response 1 (EGR1) transcription factor is essential for cell proliferation, migration and invasion, which represent some of the …

Genomic And Functional Characterization Of Vancomycin-Resistant Enterococci-Specific Bacteriophages In The Galleria Mellonella Wax Moth Larvae Model, Lynn El Haddad, Georgios Angelidakis, Justin R Clark, Jesus F Mendoza, Austen L Terwilliger, Christopher P Chaftari, Mark Duna, Serena T Yusuf, Cynthia P Harb, Mark Stibich, Anthony Maresso, Roy F Chemaly

Faculty, Staff and Students Publications

Phages are naturally occurring viruses that selectively kill bacterial species without disturbing the individual’s normal flora, averting the collateral damage of antimicrobial usage. The safety and the effectiveness of phages have been mainly confirmed in the food industry as well as in animal models. In this study, we report on the successful isolation of phages specific to Vancomycin-resistant Enterococci, including Enterococcus faecium (VREfm) and Enterococcus faecalis from sewage samples, and demonstrate their efficacy and safety for VREfm infection in the greater wax moth Galleria mellonella model. No virulence-associated genes, antibiotic resistance genes or integrases were detected in …

"Don't Look Up" Your Science-Herd Immunity Or Herd Mentality?, Botond Z Igyártó

Department of Microbiology and Immunology Faculty Papers

This analysis piece will attempt to examine some of the critical pandemic-related measures implemented in the United States from an immunological perspective and pinpoint caveats that should have been considered before their implementation. I also discuss alternative measures grounded in scientific data that were not thoroughly explored and likely could have helped fight the pandemic.

Solid-State Nmr Analysis Of Unlabeled Fungal Cell Walls From Aspergillus And Candida Species, Liyanage D. Fernando, Malitha C. Dickwella Widanage, S. Chandra Shekar, Frederic Mentink-Vigier, Ping Wang, Sungsool Wi, Tuo Wang

School of Medicine Faculty Publications

Fungal infections cause high mortality in immunocompromised individuals, which has emerged as a significant threat to human health. The efforts devoted to the development of antifungal agents targeting the cell wall polysaccharides have been hindered by our incomplete picture of the assembly and remodeling of fungal cell walls. High-resolution solid-state nuclear magnetic resonance (ss NMR) studies have substantially revised our understanding of the polymorphic structure of polysaccharides and the nanoscale organization of cell walls in Aspergillus fumigatus and multiple other fungi. However, this approach requires 13C/15N-enrichment of the sample being studied, severely restricting its application. Here we employ the dynamic …

Hippo-Taz Signaling Is The Master Regulator Of The Onset Of Triple-Negative Basal-Like Breast Cancers, Hirotoshi Soyama, Miki Nishio, Junji Otani, Toshiko Sakuma, Shintaro Takao, Shigeo Hara, Takaaki Masuda, Koshi Mimori, Shinya Toyokuni, John P Lydon, Kazuwa Nakao, Hiroshi Nishina, Takumi Fukumoto, Tomohiko Maehama, Akira Suzuki

Faculty, Staff and Students Publications

A universal oncogenic driver of basal-like breast cancer (BLBC) has resisted identification. We show that continuous transcriptional coactivator with PDZ-binding motif (TAZ) activation in precancerous murine luminal cells generates luminal cancers that later become BLBCs. Subsequent TP53 alteration, a feature of invasive human BLBCs, accelerates tumor progression. Because BLBC development is inhibited by TAZ inactivation in vivo, our work provides a sound rationale for targeting Hippo-TAZ signaling as therapy for human BLBC. Our mouse model of BLBC represents a powerful tool for evaluating such drugs.

The Unique Seed Protein Composition Of Quality Protein Popcorn Promotes Growth Of Beneficial Bacteria From The Human Gut Microbiome, Nate Korth, Leandra Parsons, Mallory J. Van Haute, Qinnan Yang, Preston Hurst, James C. Schnable, David R. Holding, Andrew K. Benson

Food for Health: Publications

The effects of fiber, complex carbohydrates, lipids, and small molecules from food matrices on the human gut microbiome have been increasingly studied. Much less is known about how dietary protein can influence the composition and function of the gut microbial community. Here, we used near-isogenic maize lines of conventional popcorn and quality-protein popcorn (QPP) to study the effects of the opaque-2 mutation and associated quality-protein modifiers on the human gut microbiome. Opaque-2 blocks the synthesis of major maize seed proteins (α-zeins), resulting in a compensatory synthesis of new seed proteins that are nutritionally beneficial with substantially higher levels …

Comparison Of Flash-Free And Conventional Bonding Systems: A Systematic Review And Meta-Analysis, He Wang, Ge Feng, Bo Hu, Haonan Tian, Yunchun Kuang, Tingwei Zhang, Jinlin Song

Faculty, Staff and Student Publications

OBJECTIVES: To review the literature systematically to compare the performance of adhesive precoated flash-free bonding systems with conventional adhesive precoated (APC) and operator-coated (OPC) bonding systems.

MATERIALS AND METHODS: PubMed, Cochrane Library, Web of Science, and Embase were searched for potential eligible studies. Study selection and data collection were conducted independently. Statistical analysis was performed by Review Manager 5.3. The Cochran Q test was used to test heterogeneity in the included studies. Risk of bias was evaluated using Cochrane RoB 2.0 tool for randomized controlled trials.

RESULTS: Six studies were included and the overall risk-of-bias judgment was low risk of …

Internal Standard Triggered-Parallel Reaction Monitoring Mass Spectrometry Enables Multiplexed Quantification Of Candidate Biomarkers In Plasma, Jacob J Kennedy, Jeffrey R Whiteaker, Richard G Ivey, Aura Burian, Shrabanti Chowdhury, Chia-Feng Tsai, Tao Liu, Chenwei Lin, Oscar D Murillo, Rachel A Lundeen, Lisa A Jones, Philip R Gafken, Gary Longton, Karin D Rodland, Steven J Skates, John Landua, Pei Wang, Michael T Lewis, Amanda G Paulovich

Faculty, Staff and Students Publications

Despite advances in proteomic technologies, clinical translation of plasma biomarkers remains low, partly due to a major bottleneck between the discovery of candidate biomarkers and costly clinical validation studies. Due to a dearth of multiplexable assays, generally only a few candidate biomarkers are tested, and the validation success rate is accordingly low. Previously, mass spectrometry-based approaches have been used to fill this gap but feature poor quantitative performance and were generally limited to hundreds of proteins. Here, we demonstrate the capability of an internal standard triggered-parallel reaction monitoring (IS-PRM) assay to greatly expand the numbers of candidates that can be …

Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

n this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the …

Maternal Adipocyte Connexin43 Gap Junctions Affect Breastmilk Lactose Levels And Neonate Growth In Mice, Mingyang Huang, Anying Song, Xi Chen, Sarah Ishtiaq, Chunmei Wang, Darryl L Hadsell, Qiong A Wang, Yi Zhu

Faculty, Staff and Students Publications

Simple Summary

Breastfeeding offers many health benefits for both mothers and infants. However, overnutrition and a steady increase in obesity in the U.S. has made it harder for many mothers to produce and express breastmilk. Moreover, the quality of breastmilk from obese mothers is frequently compromised in that it contains fewer nutrients and more inflammatory components. In this study, we used mice to model this phenomenon. We found that short-term high-fat feeding at the start of breeding reduces litter size and pups’ body weight. It also impairs adipocyte remodeling during lactation. Connexin43 is the primary building block for gap junctions …

Tracking The Source Of Helicobacter Pylori In Watersheds Of San Juan, Puerto Rico, Mary Elizabeth Sailors

Biology Theses

Helicobacter pylori is a pathogenic bacterium that infects more than half of the world’s population. The large number of H. pylori infections in Puerto Rico could be related to the waterborne transmission of the pathogen. While the San Juan Bay Estuary (SJBE) system is home to over three million people, water quality studies in this area of Puerto Rico are lacking. The goal of this study is to determine seasonal and yearly (2020-2021) shifts and relationships between the presence of H. pylori and host-specific (human and dog) Bacteroides in streams that flow through the northern coastal zone of Puerto Rico …

Molecular Mechanisms Underlying Mucosal Attachment And Colonization By Clostridioides Difficile, Ben Sidner

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Clostridioides difficile is a Gram-positive, spore-forming, anaerobic bacterium which causes gastrointestinal disease and is a leading cause of nosocomial infections. Although infection typically occurs following antibiotic therapy, in recent years there has been an increase in infections which are not preceded by antibiotic use. Additionally, community-associated infections and rates of disease recurrence have increased. While it is understood that a healthy gastrointestinal microbiota provides protection against infection, the molecular mechanisms which underly C. difficile's ability to colonize and persist in the gut are mostly unknown. Building on work from others that suggests C. difficile associates with the outer mucus …

Kalium Channelrhodopsins Are Natural Light-Gated Potassium Channels That Mediate Optogenetic Inhibition, Elena G Govorunova, Yueyang Gou, Oleg A Sineshchekov, Hai Li, Xiaoyu Lu, Yumei Wang, Leonid S Brown, François St-Pierre, Mingshan Xue, John L Spudich

Faculty, Staff and Student Publications

Channelrhodopsins are used widely for optical control of neurons, in which they generate photoinduced proton, sodium or chloride influx. Potassium (K+) is central to neuron electrophysiology, yet no natural K+-selective light-gated channel has been identified. Here, we report kalium channelrhodopsins (KCRs) from Hyphochytrium catenoides. Previously known gated potassium channels are mainly ligand- or voltage-gated and share a conserved K+-selectivity filter. KCRs differ in that they are light-gated and have independently evolved an alternative K+ selectivity mechanism. The KCRs are potent, highly selective of K+ over Na+, and open in less than 1 ms following photoactivation. The permeability ratio PK/PNa of …

Mir-181a Promotes Multiple Protumorigenic Functions By Targeting Tgfβr3, Vida Chitsazzadeh, Tran N Nguyen, Alvaro De Mingo Pulido, Bruna B Bittencourt, Lili Du, Charles H Adelmann, Ivannie Ortiz Rivera, Kimberly A Nguyen, Leah D Guerra, Andrew Davis, Marco Napoli, Wencai Ma, Richard Eric Davis, Kimal Rajapakshe, Cristian Coarfa, Elsa R Flores, Kenneth Y Tsai

Faculty, Staff and Students Publications

Cutaneous squamous cell carcinoma (cSCC) comprises 15‒20% of all skin cancers and has a well-defined progression sequence from precancerous actinic keratosis to invasive cSCC. To identify targets for chemoprevention, we previously reported a cross-species analysis to identify the transcriptional drivers of cSCC development and identified miR-181a as a potential oncomiR. We show that the upregulation of miR-181a promotes multiple protumorigenic properties by targeting an understudied component of TGFβ signaling, TGFβR3. miR-181a and TGFβR3 are upregulated and downregulated, respectively, in cSCC. miR-181a overexpression (OE) and TGFβR3 knockdown (KD) significantly suppresses UV-induced apoptosis in HaCaT cells and in primary normal human epidermal …

Deletion Of The Lmna Gene In Fibroblasts Causes Senescence-Associated Dilated Cardiomyopathy By Activating The Double-Stranded Dna Damage Response And Induction Of Senescence-Associated Secretory Phenotype, Leila Rouhi, Gaelle Auguste, Qiong Zhou, Raffaella Lombardi, Melis Olcum, Kimia Pourebrahim, Sirisha M Cheedipudi, Saman Asghar, Kui Hong, Matthew J Robertson, Cristian Coarfa, Priyatansh Gurha, Ali J Marian

Faculty, Staff and Students Publications

INTRODUCTION: Mutations in the LMNA gene, encoding Lamin A/C (LMNA), are established causes of dilated cardiomyopathy (DCM). The phenotype is typically characterized by progressive cardiac conduction defects, arrhythmias, heart failure, and premature death. DCM is primarily considered a disease of cardiac myocytes. However, LMNA is also expressed in other cardiac cell types, including fibroblasts.

AIM: The purpose of the study was to determine the contribution of the fibroblasts to DCM caused by LMNA deficiency.

METHODS AND RESULTS: The Lmna gene was deleted by crossing the platelet-derived growth factor receptor α-Cre recombinase (Pdgfra-Cre) and floxed Lmna (LmnaF/F) …