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Full-Text Articles in Medical Microbiology

Candida Auris-Macrophage Cellular Interactions And Transcriptional Response, Pedro Miramón, Andrew W Pountain, Michael C Lorenz Nov 2023

Candida Auris-Macrophage Cellular Interactions And Transcriptional Response, Pedro Miramón, Andrew W Pountain, Michael C Lorenz

Faculty, Staff and Student Publications

The pathogenic yeast Candida auris represents a global threat of the utmost clinical relevance. This emerging fungal species is remarkable in its resistance to commonly used antifungal agents and its persistence in the nosocomial settings. The innate immune system is one the first lines of defense preventing the dissemination of pathogens in the host. C. auris is susceptible to circulating phagocytes, and understanding the molecular details of these interactions may suggest routes to improved therapies. In this work, we examined the interactions of this yeast with macrophages. We found that macrophages avidly phagocytose C. auris; however, intracellular replication is …


The Microtubule Quartet Protein Snap1 In Trypanosoma Brucei Facilitates Flagellum And Cell Division Plane Positioning By Promoting Basal Body Segregation, Thiago Souza Onofre, Kieu T M Pham, Qing Zhou, Ziyin Li Nov 2023

The Microtubule Quartet Protein Snap1 In Trypanosoma Brucei Facilitates Flagellum And Cell Division Plane Positioning By Promoting Basal Body Segregation, Thiago Souza Onofre, Kieu T M Pham, Qing Zhou, Ziyin Li

Faculty, Staff and Student Publications

The unicellular protozoan Trypanosoma brucei has a single flagellum that is involved in cell motility, cell morphogenesis, and cell division. Inheritance of the newly assembled flagellum during the cell cycle requires its correct positioning, which depends on the faithful duplication or segregation of multiple flagellum-associated cytoskeletal structures, including the basal body, the flagellum attachment zone, and the hook complex. Along the flagellum attachment zone sites a set of four microtubules termed the microtubule quartet (MtQ), whose molecular function remains enigmatic. We recently reported that the MtQ-localized protein NHL1 interacts with the microtubule-binding protein TbSpef1 and regulates flagellum inheritance by promoting …


Ligand-Displaying Escherichia Coli Cells And Minicells For Programmable Delivery Of Toxic Payloads Via Type Iv Secretion Systems, Yang Grace Li, Kouhei Kishida, Natsumi Ogawa-Kishida, Peter J Christie Oct 2023

Ligand-Displaying Escherichia Coli Cells And Minicells For Programmable Delivery Of Toxic Payloads Via Type Iv Secretion Systems, Yang Grace Li, Kouhei Kishida, Natsumi Ogawa-Kishida, Peter J Christie

Faculty, Staff and Student Publications

Bacterial type IV secretion systems (T4SSs) are highly versatile macromolecular translocators and offer great potential for deployment as delivery systems for therapeutic intervention. One major T4SS subfamily, the conjugation machines, are well-adapted for delivery of DNA cargoes of interest to other bacteria or eukaryotic cells but generally exhibit modest transfer frequencies and lack specificity for target cells. Here, we tested the efficacy of a surface-displayed nanobody/antigen (Nb/Ag) pairing system to enhance the conjugative transfer of IncN (pKM101), IncF (F/pOX38), or IncP (RP4) plasmids, or of mobilizable plasmids including those encoding CRISPR/Cas9 systems (pCrispr), to targeted recipient cells. Escherichia coli donors …


Coordination Between Aminoacylation And Editing To Protect Against Proteotoxicity, Hong Zhang, Parker Murphy, Jason Yu, Sukyeong Lee, Francis T F Tsai, Ambro Van Hoof, Jiqiang Ling Oct 2023

Coordination Between Aminoacylation And Editing To Protect Against Proteotoxicity, Hong Zhang, Parker Murphy, Jason Yu, Sukyeong Lee, Francis T F Tsai, Ambro Van Hoof, Jiqiang Ling

Faculty, Staff and Student Publications

Aminoacyl-tRNA synthetases (aaRSs) are essential enzymes that ligate amino acids to tRNAs, and often require editing to ensure accurate protein synthesis. Recessive mutations in aaRSs cause various neurological disorders in humans, yet the underlying mechanism remains poorly understood. Pathogenic aaRS mutations frequently cause protein destabilization and aminoacylation deficiency. In this study, we report that combined aminoacylation and editing defects cause severe proteotoxicity. We show that the ths1-C268A mutation in yeast threonyl-tRNA synthetase (ThrRS) abolishes editing and causes heat sensitivity. Surprisingly, experimental evolution of the mutant results in intragenic mutations that restore heat resistance but not editing. ths1-C268A destabilizes ThrRS and …


Catalase Produced By Candida Albicans Protects Streptococcus Mutans From H2o2 Stress-One More Piece In The Cross-Kingdom Synergism Puzzle, Callahan Katrak, Bruna A Garcia, Louise M Dornelas-Figueira, Mary Nguyen, Robert B Williams, Michael C Lorenz, Jacqueline Abranches Oct 2023

Catalase Produced By Candida Albicans Protects Streptococcus Mutans From H2o2 Stress-One More Piece In The Cross-Kingdom Synergism Puzzle, Callahan Katrak, Bruna A Garcia, Louise M Dornelas-Figueira, Mary Nguyen, Robert B Williams, Michael C Lorenz, Jacqueline Abranches

Faculty, Staff and Student Publications

Co-infection with Streptococcus mutans and Candida albicans is associated with dental caries, and their co-cultivation results in enhanced biofilm matrix production that contributes to increased virulence and caries risk. Moreover, the catalase-negative S. mutans demonstrates increased oxidative stress tolerance when co-cultivated in biofilms with C. albicans, a catalase-producing yeast. Here, we sought to obtain mechanistic insights into the increased H2O2 tolerance of S. mutans when co-cultivated with clinical isolates of Candida glabrata, Candida tropicalis, and C. albicans. Additionally, the C. albicans SC5314 laboratory strain, its catalase mutant (SC5314Δcat1), and S. mutans UA159 and its glucosyltransferase B/C …


Stepwise Implementation Of 2d Synthesized Screening Mammography And Its Effect On Stereotactic Biopsy Of Microcalcifications, Bo Hu, Lixue Gai, Yonglei Liu, Pan Wang, Shuping Yu, Li Zhu, Xijiang Han, Yunchen Du Oct 2023

Stepwise Implementation Of 2d Synthesized Screening Mammography And Its Effect On Stereotactic Biopsy Of Microcalcifications, Bo Hu, Lixue Gai, Yonglei Liu, Pan Wang, Shuping Yu, Li Zhu, Xijiang Han, Yunchen Du

Faculty, Staff and Student Publications

Electromagnetic wave absorbing materials (EWAMs) have made great progress in the past decades, and are playing an increasingly important role in radiation prevention and antiradar detection due to their essential attenuation toward incident EM wave. With the flourish of nanotechnology, the design of high-performance EWAMs is not just dependent on the intrinsic characteristics of single-component medium, but pays more attention to the synergistic effects from different components to generate rich loss mechanisms. Among various candidates, carbides and carbon materials are usually labeled with the features of chemical stability, low density, tunable dielectric property, and diversified morphology/microstructure, and thus the combination …


The Effect Of Heat-Moisture Treatment Changed The Binding Of Starch, Protein And Lipid In Rice Flour To Affect Its Hierarchical Structure And Physicochemical Properties, Seung Hee Yoo, Mi Jin Jue, Yu-Hee Kim, Sooyoung Cho, Won-Joong Kim, Kye-Min Kim, Jong In Han, Heeseung Lee Oct 2023

The Effect Of Heat-Moisture Treatment Changed The Binding Of Starch, Protein And Lipid In Rice Flour To Affect Its Hierarchical Structure And Physicochemical Properties, Seung Hee Yoo, Mi Jin Jue, Yu-Hee Kim, Sooyoung Cho, Won-Joong Kim, Kye-Min Kim, Jong In Han, Heeseung Lee

Faculty, Staff and Student Publications

Dexmedetomidine prevents postoperative cognitive dysfunction by inhibiting high-mobility group box 1 (HMGB1), which acts as an inflammatory marker. This study investigated the HMGB1 levels and the cognitive function using a Mini-Cog© score in elderly patients undergoing orthopedic surgery with dexmedetomidine infusion. In total, 128 patients aged ≥ 65 years were analyzed. The patients received saline in the control group and dexmedetomidine in the dexmedetomidine group until the end of surgery. Blood sampling and the Mini-Cog© test were performed before the surgery and on postoperative days 1 and 3. The primary outcomes were the effect of dexmedetomidine on the HMGB1 levels …


Phenotype And Fate Of Liver-Resident Cd8 T Cells During Acute And Chronic Hepacivirus Infection, Piyush Dravid, Satyapramod Murthy, Zayed Attia, Cole Cassady, Rahul Chandra, Sheetal Trivedi, Ashish Vyas, John Gridley, Brantley Holland, Anuradha Kumari, Arash Grakoui, John M Cullen, Christopher M Walker, Himanshu Sharma, Amit Kapoor Oct 2023

Phenotype And Fate Of Liver-Resident Cd8 T Cells During Acute And Chronic Hepacivirus Infection, Piyush Dravid, Satyapramod Murthy, Zayed Attia, Cole Cassady, Rahul Chandra, Sheetal Trivedi, Ashish Vyas, John Gridley, Brantley Holland, Anuradha Kumari, Arash Grakoui, John M Cullen, Christopher M Walker, Himanshu Sharma, Amit Kapoor

Faculty, Staff and Student Publications

Immune correlates of hepatitis C virus (HCV) clearance and control remain poorly defined due to the lack of an informative animal model. We recently described acute and chronic rodent HCV-like virus (RHV) infections in lab mice. Here, we developed MHC class I and class II tetramers to characterize the serial changes in RHV-specific CD8 and CD4 T cells during acute and chronic infection in C57BL/6J mice. RHV infection induced rapid expansion of T cells targeting viral structural and nonstructural proteins. After virus clearance, the virus-specific T cells transitioned from effectors to long-lived liver-resident memory T cells (TRM). The effector and …


Development Of A Xylose-Inducible Promoter And Riboswitch Combination System For Manipulating Gene Expression In Fusobacterium Nucleatum, Bibek G C, Peng Zhou, Arindam Naha, Jianhua Gu, Chenggang Wu Sep 2023

Development Of A Xylose-Inducible Promoter And Riboswitch Combination System For Manipulating Gene Expression In Fusobacterium Nucleatum, Bibek G C, Peng Zhou, Arindam Naha, Jianhua Gu, Chenggang Wu

Faculty, Staff and Student Publications

Inducible gene expression systems are important for studying bacterial gene function, yet most exhibit leakage. In this study, we engineered a leakage-free hybrid system for precise gene expression controls in Fusobacterium nucleatum by integrating the xylose-inducible expression system with the theophylline-responsive riboswitch. This innovative method enables concurrent control of target gene expression at both transcription and translation initiation levels. Using luciferase and the indole-producing enzyme tryptophanase (TnaA) as reporters, we demonstrated that the hybrid system displays virtually no observable signal in the absence of inducers. We employed this system to express FtsX, a protein related to fusobacterial cytokinesis, in an …


Applications Of Degradable Hydrogels In Novel Approaches To Disease Treatment And New Modes Of Drug Delivery, Bo Hu, Jinyuan Gao, Yu Lu, Yuji Wang Sep 2023

Applications Of Degradable Hydrogels In Novel Approaches To Disease Treatment And New Modes Of Drug Delivery, Bo Hu, Jinyuan Gao, Yu Lu, Yuji Wang

Faculty, Staff and Student Publications

Hydrogels are particularly suitable materials for loading drug delivery agents; their high water content provides a biocompatible environment for most biomolecules, and their cross-linked nature protects the loaded agents from damage. During delivery, the delivered substance usually needs to be released gradually over time, which can be achieved by degradable cross-linked chains. In recent years, biodegradable hydrogels have become a promising technology in new methods of disease treatment and drug delivery methods due to their many advantageous properties. This review briefly discusses the degradation mechanisms of different types of biodegradable hydrogel systems and introduces the specific applications of degradable hydrogels …


Using Co-Creation Focus Groups To Customise A Remote Multidomain Programme Designed To Increase Dementia Literacy, Walter Wittich, Edeltraut Kröger, Gabrielle Aubin, Asma Fadhlaoui, Nicole D Anderson, Nouha Ben Gaied, Inbal Itzhak, Sylvie Belleville Sep 2023

Using Co-Creation Focus Groups To Customise A Remote Multidomain Programme Designed To Increase Dementia Literacy, Walter Wittich, Edeltraut Kröger, Gabrielle Aubin, Asma Fadhlaoui, Nicole D Anderson, Nouha Ben Gaied, Inbal Itzhak, Sylvie Belleville

Faculty, Staff and Student Publications

Objectives

To adapt the content and functionalities of Brain Health PRO, a web-based multidomain program designed to increase dementia literacy, to the context and needs of users, providers and community organisations across Québec, Canada.

Design

Five consecutive qualitative co-creation focus group sessions 30–90 min in duration each, exploring potential barriers and facilitators to usability, accessibility, comprehensibility, participant recruitment and retention.

Setting

Virtual meetings.

Participants

A 15-member team based in Québec and Ontario, Canada, consisting of 9 researchers (including a graduate student and the project coordinator), representing occupational therapy, sensory rehabilitation, neuropsychology, psychology, health science and research methods, 3 informal caregivers …


Global Proteomic Identifies Multiple Cancer-Related Signaling Pathways Altered By A Gut Pathobiont Associated With Colorectal Cancer, Ewa Pasquereau-Kotula, Giulia Nigro, Florent Dingli, Damarys Loew, Patrick Poullet, Yi Xu, Scott Kopetz, Jennifer Davis, Lucie Peduto, Catherine Robbe-Masselot, Philippe Sansonetti, Patrick Trieu-Cuot, Shaynoor Dramsi Sep 2023

Global Proteomic Identifies Multiple Cancer-Related Signaling Pathways Altered By A Gut Pathobiont Associated With Colorectal Cancer, Ewa Pasquereau-Kotula, Giulia Nigro, Florent Dingli, Damarys Loew, Patrick Poullet, Yi Xu, Scott Kopetz, Jennifer Davis, Lucie Peduto, Catherine Robbe-Masselot, Philippe Sansonetti, Patrick Trieu-Cuot, Shaynoor Dramsi

Faculty, Staff and Student Publications

In this work, we investigated the oncogenic role of Streptococcus gallolyticus subsp. gallolyticus (SGG), a gut bacterium associated with colorectal cancer (CRC). We showed that SGG UCN34 accelerates colon tumor development in a chemically induced CRC murine model. Full proteome and phosphoproteome analysis of murine colons chronically colonized by SGG UCN34 revealed that 164 proteins and 725 phosphorylation sites were differentially regulated. Ingenuity Pathway Analysis (IPA) indicates a pro-tumoral shift specifically induced by SGG UCN34, as ~ 90% of proteins and phosphoproteins identified were associated with digestive cancer. Comprehensive analysis of the altered phosphoproteins using ROMA software revealed up-regulation of …


The Classification Of Obesity Based On Metabolic Status Redefines The Readmission Of Non-Hodgkin’S Lymphoma—An Observational Study, Eunju Kim, Kazuaki Mawatari, Seung-Hee Yoo, Zheng Chen Sep 2023

The Classification Of Obesity Based On Metabolic Status Redefines The Readmission Of Non-Hodgkin’S Lymphoma—An Observational Study, Eunju Kim, Kazuaki Mawatari, Seung-Hee Yoo, Zheng Chen

Faculty, Staff and Student Publications

Obesity is a known risk factor for metabolic diseases and is often associated with chronic inflammation in adipose tissue. We previously identified the polyethoxylated flavonoid Nobiletin (NOB) as a circadian clock modulator that directly binds to and activates the ROR receptors in the core oscillator, markedly improving metabolic fitness in obese mice. Here, we show that NOB enhanced the oscillation of core clock genes in differentiated 3T3-L1 adipocytes, including ROR target genes such as Bmal1, Cry1, Dec1, and Dec2. NOB inhibited lipid accumulation in 3T3-L1 and SVF cells, concomitant with the dysregulated circadian expression of adipogenic …


Interoceptive Regulation Of Skeletal Tissue Homeostasis And Repair, Yao Xiao, Changhao Han, Yunhao Wang, Xinshu Zhang, Rong Bao, Yuange Li, Huajiang Chen, Bo Hu, Shen Liu Sep 2023

Interoceptive Regulation Of Skeletal Tissue Homeostasis And Repair, Yao Xiao, Changhao Han, Yunhao Wang, Xinshu Zhang, Rong Bao, Yuange Li, Huajiang Chen, Bo Hu, Shen Liu

Faculty, Staff and Student Publications

Recent studies have determined that the nervous system can sense and respond to signals from skeletal tissue, a process known as skeletal interoception, which is crucial for maintaining bone homeostasis. The hypothalamus, located in the central nervous system (CNS), plays a key role in processing interoceptive signals and regulating bone homeostasis through the autonomic nervous system, neuropeptide release, and neuroendocrine mechanisms. These mechanisms control the differentiation of mesenchymal stem cells into osteoblasts (OBs), the activation of osteoclasts (OCs), and the functional activities of bone cells. Sensory nerves extensively innervate skeletal tissues, facilitating the transmission of interoceptive signals to the CNS. …


Host-Derived Reactive Oxygen Species Trigger Activation Of The Candida Albicans Transcription Regulator Rtg1/3, Mazen Oneissi, Melissa R Cruz, Bernardo Ramírez-Zavala, Elena Lindemann-Perez, Joachim Morschhäuser, Danielle A Garsin, J Christian Perez Sep 2023

Host-Derived Reactive Oxygen Species Trigger Activation Of The Candida Albicans Transcription Regulator Rtg1/3, Mazen Oneissi, Melissa R Cruz, Bernardo Ramírez-Zavala, Elena Lindemann-Perez, Joachim Morschhäuser, Danielle A Garsin, J Christian Perez

Faculty, Staff and Student Publications

The signals that denote mammalian host environments and dictate the activation of signaling pathways in human-associated microorganisms are often unknown. The transcription regulator Rtg1/3 in the human fungal pathogen Candida albicans is a crucial determinant of host colonization and pathogenicity. Rtg1/3's activity is controlled, in part, by shuttling the regulator between the cytoplasm and nucleus of the fungus. The host signal(s) that Rtg1/3 respond(s) to, however, have remained unclear. Here we report that neutrophil-derived reactive oxygen species (ROS) direct the subcellular localization of this C. albicans transcription regulator. Upon engulfment of Candida cells by human or mouse neutrophils, the regulator …


New Insights Into Rna Processing By The Eukaryotic Trna Splicing Endonuclease, Cassandra K Hayne, Samoil Sekulovski, Jennifer E Hurtig, Robin E Stanley, Simon Trowitzsch, Ambro Van Hoof Sep 2023

New Insights Into Rna Processing By The Eukaryotic Trna Splicing Endonuclease, Cassandra K Hayne, Samoil Sekulovski, Jennifer E Hurtig, Robin E Stanley, Simon Trowitzsch, Ambro Van Hoof

Faculty, Staff and Student Publications

Through its role in intron cleavage, tRNA splicing endonuclease (TSEN) plays a critical function in the maturation of intron-containing pre-tRNAs. The catalytic mechanism and core requirement for this process is conserved between archaea and eukaryotes, but for decades, it has been known that eukaryotic TSENs have evolved additional modes of RNA recognition, which have remained poorly understood. Recent research identified new roles for eukaryotic TSEN, including processing or degradation of additional RNA substrates, and determined the first structures of pre-tRNA-bound human TSEN complexes. These recent discoveries have changed our understanding of how the eukaryotic TSEN targets and recognizes substrates. Here, …


Cell Entry And Release Of Quasi-Enveloped Human Hepatitis Viruses, Anshuman Das, Efraín E Rivera-Serrano, Xin Yin, Christopher M Walker, Zongdi Feng, Stanley M Lemon Sep 2023

Cell Entry And Release Of Quasi-Enveloped Human Hepatitis Viruses, Anshuman Das, Efraín E Rivera-Serrano, Xin Yin, Christopher M Walker, Zongdi Feng, Stanley M Lemon

Faculty, Staff and Student Publications

Infectious hepatitis type A and type E are caused by phylogenetically distinct single-stranded, positive-sense RNA viruses that were once considered to be non-enveloped. However, studies show that both are released nonlytically from hepatocytes as 'quasi-enveloped' virions cloaked in host membranes. These virion types predominate in the blood of infected individuals and mediate virus spread within the liver. They lack virally encoded proteins on their surface and are resistant to neutralizing anti-capsid antibodies induced by infection, yet they efficiently enter cells and initiate new rounds of virus replication. In this Review, we discuss the mechanisms by which specific peptide sequences in …


Bame Directly Interacts With Bama And Bamd Coordinating Their Functions, Santosh Kumar, Anna Konovalova Sep 2023

Bame Directly Interacts With Bama And Bamd Coordinating Their Functions, Santosh Kumar, Anna Konovalova

Faculty, Staff and Student Publications

The β-barrel assembly machinery (Bam) complex facilitates the assembly of outer membrane proteins (OMPs) in gram-negative bacteria. The Bam complex is conserved and essential for bacterial viability and consists of five subunits, BamA-E. BamA is the transmembrane component, and its β-barrel domain opens laterally to allow folding and insertion of incoming OMPs. The remaining components are regulatory, among which only BamD is essential. Previous studies suggested that BamB regulates BamA directly, while BamE and BamC serve as BamD regulators. However, specific molecular details of their functions remain unknown. Our previous research demonstrated that BamE plays a specialized role in assembling …


Phylogenetic Inference From Single-Cell Rna-Seq Data, Xuan Liu, Jason I Griffiths, Isaac Bishara, Jiayi Liu, Andrea H Bild, Jeffrey T Chang Aug 2023

Phylogenetic Inference From Single-Cell Rna-Seq Data, Xuan Liu, Jason I Griffiths, Isaac Bishara, Jiayi Liu, Andrea H Bild, Jeffrey T Chang

Faculty, Staff and Student Publications

Tumors are comprised of subpopulations of cancer cells that harbor distinct genetic profiles and phenotypes that evolve over time and during treatment. By reconstructing the course of cancer evolution, we can understand the acquisition of the malignant properties that drive tumor progression. Unfortunately, recovering the evolutionary relationships of individual cancer cells linked to their phenotypes remains a difficult challenge. To address this need, we have developed PhylinSic, a method that reconstructs the phylogenetic relationships among cells linked to their gene expression profiles from single cell RNA-sequencing (scRNA-Seq) data. This method calls nucleotide bases using a probabilistic smoothing approach and then …


The At-Hook Is An Evolutionarily Conserved Auto-Regulatory Domain Of Swi/Snf Required For Cell Lineage Priming, Dhurjhoti Saha, Solomon Hailu, Arjan Hada, Junwoo Lee, Jie Luo, Jeff A Ranish, Yuan-Chi Lin, Kyle Feola, Jim Persinger, Abhinav Jain, Bin Liu, Yue Lu, Payel Sen, Blaine Bartholomew Aug 2023

The At-Hook Is An Evolutionarily Conserved Auto-Regulatory Domain Of Swi/Snf Required For Cell Lineage Priming, Dhurjhoti Saha, Solomon Hailu, Arjan Hada, Junwoo Lee, Jie Luo, Jeff A Ranish, Yuan-Chi Lin, Kyle Feola, Jim Persinger, Abhinav Jain, Bin Liu, Yue Lu, Payel Sen, Blaine Bartholomew

Faculty, Staff and Student Publications

The SWI/SNF ATP-dependent chromatin remodeler is a master regulator of the epigenome, controlling pluripotency and differentiation. Towards the C-terminus of the catalytic subunit of SWI/SNF is a motif called the AT-hook that is evolutionary conserved. The AT-hook is present in many chromatin modifiers and generally thought to help anchor them to DNA. We observe however that the AT-hook regulates the intrinsic DNA-stimulated ATPase activity aside from promoting SWI/SNF recruitment to DNA or nucleosomes by increasing the reaction velocity a factor of 13 with no accompanying change in substrate affinity (K


Spatial Transcriptomics Of Intraductal Papillary Mucinous Neoplasms Of The Pancreas Identifies Nkx6-2 As A Driver Of Gastric Differentiation And Indolent Biological Potential, Marta Sans, Yuki Makino, Jimin Min, Kimal I Rajapakshe, Michele Yip-Schneider, C Max Schmidt, Mark W Hurd, Jared K Burks, Javier A Gomez, Fredrik I Thege, Johannes F Fahrmann, Robert A Wolff, Michael P Kim, Paola A Guerrero, Anirban Maitra Aug 2023

Spatial Transcriptomics Of Intraductal Papillary Mucinous Neoplasms Of The Pancreas Identifies Nkx6-2 As A Driver Of Gastric Differentiation And Indolent Biological Potential, Marta Sans, Yuki Makino, Jimin Min, Kimal I Rajapakshe, Michele Yip-Schneider, C Max Schmidt, Mark W Hurd, Jared K Burks, Javier A Gomez, Fredrik I Thege, Johannes F Fahrmann, Robert A Wolff, Michael P Kim, Paola A Guerrero, Anirban Maitra

Faculty, Staff and Student Publications

Intraductal Papillary Mucinous Neoplasms (IPMNs) of the pancreas are bona fide precursor lesions of pancreatic ductal adenocarcinoma (PDAC). The most common subtype of IPMNs harbor a gastric foveolar-type epithelium, and these low-grade mucinous neoplasms are harbingers of IPMNs with high-grade dysplasia and cancer. The molecular underpinning of gastric differentiation in IPMNs is unknown, although identifying drivers of this indolent phenotype might enable opportunities for intercepting progression to high-grade IPMN and cancer. We conducted spatial transcriptomics on a cohort of IPMNs, followed by orthogonal and cross species validation studies, which established the transcription factor NKX6-2 as a key determinant of gastric …


Two Structurally Defined Aβ Polymorphs Promote Different Pathological Changes In Susceptible Mice, Ruben Gomez-Gutierrez, Ujjayini Ghosh, Wai-Ming Yau, Nazaret Gamez, Katherine Do, Carlos Kramm, Hamid Shirani, Laura Vegas-Gomez, Jonathan Schulz, Ines Moreno-Gonzalez, Antonia Gutierrez, K Peter R Nilsson, Robert Tycko, Claudio Soto, Rodrigo Morales Aug 2023

Two Structurally Defined Aβ Polymorphs Promote Different Pathological Changes In Susceptible Mice, Ruben Gomez-Gutierrez, Ujjayini Ghosh, Wai-Ming Yau, Nazaret Gamez, Katherine Do, Carlos Kramm, Hamid Shirani, Laura Vegas-Gomez, Jonathan Schulz, Ines Moreno-Gonzalez, Antonia Gutierrez, K Peter R Nilsson, Robert Tycko, Claudio Soto, Rodrigo Morales

Faculty, Staff and Student Publications

Misfolded Aβ is involved in the progression of Alzheimer's disease (AD). However, the role of its polymorphic variants or conformational strains in AD pathogenesis is not fully understood. Here, we study the seeding properties of two structurally defined synthetic misfolded Aβ strains (termed 2F and 3F) using in vitro and in vivo assays. We show that 2F and 3F strains differ in their biochemical properties, including resistance to proteolysis, binding to strain-specific dyes, and in vitro seeding. Injection of these strains into a transgenic mouse model produces different pathological features, namely different rates of aggregation, formation of different plaque types, …


Alternative Splicing Of Ceacam1 By Hypoxia-Inducible Factor-1Α Enhances Tolerance To Hepatic Ischemia In Mice And Humans, Kenneth J Dery, Hidenobu Kojima, Shoichi Kageyama, Kentaro Kadono, Hirofumi Hirao, Brian Cheng, Yuan Zhai, Douglas G Farmer, Fady M Kaldas, Xiaoyi Yuan, Holger K Eltzschig, Jerzy W Kupiec-Weglinski Aug 2023

Alternative Splicing Of Ceacam1 By Hypoxia-Inducible Factor-1Α Enhances Tolerance To Hepatic Ischemia In Mice And Humans, Kenneth J Dery, Hidenobu Kojima, Shoichi Kageyama, Kentaro Kadono, Hirofumi Hirao, Brian Cheng, Yuan Zhai, Douglas G Farmer, Fady M Kaldas, Xiaoyi Yuan, Holger K Eltzschig, Jerzy W Kupiec-Weglinski

Faculty, Staff and Student Publications

Although alternative splicing (AS) drives transcriptional responses and cellular adaptation to environmental stresses, its contributions in organ transplantation have not been appreciated. We have shown that carcinoembryonic antigen-related cell adhesion molecule (Ceacam1; CD66a), a transmembrane biliary glycoprotein expressed in epithelial, endothelial, and immune cells, determines donor liver transplant quality. Here, we studied how AS of Ceacam1 affects ischemia-reperfusion injury (IRI) in mouse and human livers. We found that the short cytoplasmic isoform Ceacam1-S increased during early acute and late resolution phases of warm IRI injury in mice. Transfection of Ceacam1-deficient mouse hepatocytes with adenoviral Ceacam1-S mitigated hypoxia-induced loss of …


Barriers And Facilitators To Home Dialysis Among Latinx Patients With Kidney Disease, Katherine Rizzolo, Rebeca Gonzalez Jauregui, Ileana Barrientos, Jade Teakell, Claudia Camacho, Michel Chonchol, Sushrut S Waikar, Lilia Cervantes Aug 2023

Barriers And Facilitators To Home Dialysis Among Latinx Patients With Kidney Disease, Katherine Rizzolo, Rebeca Gonzalez Jauregui, Ileana Barrientos, Jade Teakell, Claudia Camacho, Michel Chonchol, Sushrut S Waikar, Lilia Cervantes

Faculty, Staff and Student Publications

Importance: Latinx people have a high burden of kidney disease but are less likely to receive home dialysis compared to non-Latinx White people. The disparity in home dialysis therapy has not been completely explained by demographic, medical, or social factors.

Objective: To understand the barriers and facilitators to home dialysis therapy experienced by Latinx individuals with kidney failure receiving home dialysis.

Design, setting, and participants: This qualitative study used semistructured interviews with Latinx adults with kidney failure receiving home dialysis therapy in Denver, Colorado, and Houston, Texas, between November 2021 and March 2023. Patients were recruited from home dialysis clinics …


Gwas-Identified Telomere Length Associated Genetic Variants Predict Risk Of Recurrence Of Hpv-Positive Oropharyngeal Cancer After Definitive Radiotherapy, Peng Sun, Peng Wei, Hongliang Liu, Jia Wu, Neil D Gross, Andrew G Sikora, Qingyi Wei, Sanjay Shete, Mark E Zafereo, Jisheng Liu, Guojun Li Aug 2023

Gwas-Identified Telomere Length Associated Genetic Variants Predict Risk Of Recurrence Of Hpv-Positive Oropharyngeal Cancer After Definitive Radiotherapy, Peng Sun, Peng Wei, Hongliang Liu, Jia Wu, Neil D Gross, Andrew G Sikora, Qingyi Wei, Sanjay Shete, Mark E Zafereo, Jisheng Liu, Guojun Li

Faculty, Staff and Student Publications

Background: Lymphocyte telomere length (LTL)-related genetic variants may modulate LTL and affect recurrence of squamous cell carcinoma of the oropharynx (SCCOP).

Methods: A total of 1013 patients with incident SCCOP were recruited and genotyped for 16 genome-wide association study (GWAS)-identified TL-related polymorphisms. Of these patients, 489 had tumour HPV16 status determination. Univariate and multivariate analyses were performed to evaluate associations.

Findings: Of the 16 TL-related polymorphisms, four were significantly associated with LTL: rs1920116, rs3027234, rs6772228, and rs11125529, and the patients with putatively favourable genotypes had approximately 1.5-3 times the likelihood of shorter LTL compared with patients with the corresponding risk …


China Stroke Surveillance Report 2021, Wen-Jun Tu, Long-De Wang, Special Writing Group Of China Stroke Surveillance Report Jul 2023

China Stroke Surveillance Report 2021, Wen-Jun Tu, Long-De Wang, Special Writing Group Of China Stroke Surveillance Report

Faculty, Staff and Student Publications

Since 2015, stroke has become the leading cause of death and disability in China, posing a significant threat to the health of its citizens as a major chronic non-communicable disease. According to the China Stroke High-risk Population Screening and Intervention Program, an estimated 17.8 million [95% confidence interval (CI) 17.6–18.0 million] adults in China had experienced a stroke in 2020, with 3.4 million (95% CI 3.3–3.5 million) experiencing their first-ever stroke and another 2.3 million (95% CI 2.2–2.4 million) dying as a result. Additionally, approximately 12.5% (95% CI 12.4–12.5%) of stroke survivors were left disabled, as defined by a modified …


Chronic Social Defeat Alters Brain Vascular-Associated Cell Gene Expression Patterns Leading To Vascular Dysfunction And Immune System Activation, Joshua D Samuels, Madison L Lotstein, Michael L Lehmann, Abdel G Elkahloun, Subhadra Banerjee, Miles Herkenham Jun 2023

Chronic Social Defeat Alters Brain Vascular-Associated Cell Gene Expression Patterns Leading To Vascular Dysfunction And Immune System Activation, Joshua D Samuels, Madison L Lotstein, Michael L Lehmann, Abdel G Elkahloun, Subhadra Banerjee, Miles Herkenham

Faculty, Staff and Student Publications

Brain vascular integrity is critical for brain health, and its disruption is implicated in many brain pathologies, including psychiatric disorders. Brain-vascular barriers are a complex cellular landscape composed of endothelial, glial, mural, and immune cells. Yet currently, little is known about these brain vascular-associated cells (BVACs) in health and disease. Previously, we demonstrated that 14 days of chronic social defeat (CSD), a mouse paradigm that produces anxiety and depressive-like behaviors, causes cerebrovascular damage in the form of scattered microbleeds. Here, we developed a technique to isolate barrier-related cells from the mouse brain and subjected the isolated cells to single-cell RNA …


Problems With Peer Review Shine A Light On Gaps In Scientific Training, Diana M Proctor, Nsa Dada, Anna Serquiña, Julia L E Willett Jun 2023

Problems With Peer Review Shine A Light On Gaps In Scientific Training, Diana M Proctor, Nsa Dada, Anna Serquiña, Julia L E Willett

Faculty, Staff and Student Publications

No abstract provided.


Hyperphosphorylation Of The Group A Streptococcal Control Of Virulence Regulator Increases Promoter Occupancy Specifically At Virulence Factor-Encoding Genes, Nicola Horstmann, Chau Nguyen Tran, Anthony R Flores, Samuel A Shelburne Jun 2023

Hyperphosphorylation Of The Group A Streptococcal Control Of Virulence Regulator Increases Promoter Occupancy Specifically At Virulence Factor-Encoding Genes, Nicola Horstmann, Chau Nguyen Tran, Anthony R Flores, Samuel A Shelburne

Faculty, Staff and Student Publications

The control of virulence two-component gene regulatory system (CovRS) is critical to the pathogenesis of many medically important streptococci. In emm1 group A streptococci (GAS), CovR directly binds the promoters of numerous GAS virulence factor-encoding genes. Elimination of CovS phosphatase activity increases CovR phosphorylation (CovR~P) levels and abrogates GAS virulence. Given the emm type-specific diversity of CovRS function, in this study we used chromatin immunoprecipitation sequencing (ChIP-seq) to define global CovR DNA occupancy in the wild-type emm3 strain MGAS10870 (medium CovR~P) and its CovS phosphatase-negative derivative 10870-CovS-T284A (high CovR~P). In the wild-type emm3 strain, 89% of the previously identified emm1 …


Stroke Survivors' Telemedicine Experiences During The Covid-19 Pandemic: A Phenomenological Investigation, Irene N Kasumba, Kit Tilly, Tao Lin, Steven J Norris, Patricia A Rosa Jun 2023

Stroke Survivors' Telemedicine Experiences During The Covid-19 Pandemic: A Phenomenological Investigation, Irene N Kasumba, Kit Tilly, Tao Lin, Steven J Norris, Patricia A Rosa

Faculty, Staff and Student Publications

The highly segmented genome of Borrelia burgdorferi, the tick-borne bacterium that causes Lyme disease, is composed of a linear chromosome and more than 20 co-existing endogenous plasmids. Many plasmid-borne genes are unique to B. burgdorferi and some have been shown to provide essential functions at discrete points of the infectious cycle between a tick vector and rodent host. In this study, we investigated the role of bba40, a highly conserved and differentially expressed gene on a ubiquitous linear plasmid of B. burgdorferi. In a prior genome-wide analysis, inactivation of bba40 by transposon insertion was linked with a …