Microbiology Commons^™

Resistant & Persistent Bacterial Cells, Jean-Louis Bru

Open Educational Resources

An activity on the difference between resistant & persistent bacterial cells. This activity aims to build on the pre-lecture materials about resistant bacterial cells, so that students can make a connection toward persistent cells. In both cases, they make antibiotics less effective.

Learning Objectives

Recognize the importance of antibiotics in fighting bacterial infections. Understand how bacterial species become antibiotic resistant. Determine the difference between resistant and persistent bacterial cells.

Social and Collaborative

Students work together on this in-class activity in groups of 2-4 (3, ideally). Each student will have one of the following roles: encourager, recorded, investigator, and time keeper. …

Clinical Characteristics And Outcomes Of Pediatric Staphylococcal Scalded Skin Syndrome (Ssss) At An Inner-City Tertiary Care Center, Nina Kb Gust Md, Ashley Frei Bs, Rebecca M. Adams Bs, Elika Ridelman Phd, Christina Shanti Md, Ronald Thomas Phd, Jocelyn Y. Ang Md

Medical Student Research Symposium

Introduction

Staphylococcal Scalded Skin Syndrome (SSSS) is a blistering skin condition caused by a toxin-producing staphylococcus species. Epidemiologic studies on pediatric SSSS in the United States are limited, with a reported incidence of 7.67 cases per million children and 45.1 per million infants. Immature renal function, lack of protective antibodies, and increased exotoxin target desmoglein-1 are hypothesized to increase incidence in younger children. We aimed to determine clinical and microbiological characteristics of pediatric SSSS and factors that could help predict disease severity.

Methods

A retrospective chart review was performed for admitted patients under 18 years old diagnosed with SSSS from …

Modeling The Cystic Fibrosis Intestinal Environment To Study Microbial Interactions, Kaitlyn Emma Barrack

Dartmouth College Ph.D Dissertations

The microbiome of the cystic fibrosis (CF) intestine is altered significantly in structure and function beginning in early life. Key taxa associated with health, digestion and immune-training are reduced in abundance, including but not limited to Bacteroides, Faecalibacterium, Akkermansia, Ruminococcus and other short-chain fatty acid producers. Conversely, there is an expansion of microbes with pathogenic potential, such as Escherichia, Veillonella, Pseudomonas and Staphylococcus. The shifts in microbiota composition direct community-wide changes with differences in beta diversity by genotype, whereby children with CF (cwCF) exhibit significantly different gut microbial compositions compared to nonCF children. Additionally, shifts in microbiota structure often …

Bone-Induced Her2 Promotes Secondary Metastasis In Hr+/Her2- Breast Cancer, Rahat Alam, Anna Reva, David G Edwards, Bree M Lege, Laura S Munoz-Arcos, Carolina Reduzzi, Swarnima Singh, Xiaoxin Hao, Yi-Hsuan Wu, Zeru Tian, Laura M Natalee, Gargi Damle, Deniz Demircioglu, Yixian Wang, Ling Wu, Elisabetta Molteni, Dan Hasson, Bora Lim, Zbigniew Gugala, Jerry E Chipuk, Julie E Lang, Joseph A Sparano, Chonghui Cheng, Massimo Cristofanilli, Han Xiao, Xiang H-F Zhang, Igor L Bado

Faculty, Staff and Students Publications

Bone metastases can disseminate to secondary sites and promote breast cancer progression creating additional clinical challenges. The mechanisms contributing to secondary metastasis are barely understood. Here, we evaluate the prediction power of Her2-expressing (Her2E) circulating tumor cells (CTCs) after analyzing over 13,000 CTCs from a cohort of 137 metastatic breast cancer (MBC) patients with initial HR+/Her2− status and employ preclinical models of bone metastasis (BM) to validate the role of Her2E CTCs in multi-organ metastases. While Her2 expression was higher in patients with bone metastasis, experimental analyses revealed that Her2E CTCs derived from bone lesions were more dependent on Her2 …

Life Line Spring 2025, Otterbein Biology And Earth Science Department

Life Line - The Biology Department Newsletter

In this issue:

Greetings and Farewell!; COSI 2024; Ketchup, Culture, and an Unforgettable Conference; Alumna Earns PhD; Tortoises, Butterflies, and Cockroaches, Oh My!; Licking River Roundup 2024; Aquarium Students Explore Coral Restoration in Fiji; The Galapagos Islands: Geology, Ecology, Conservation, and Culture; Dr. Svitana Presents on Otterbein Lake Well Field; Cell Bio Pilots Unique Approach to Learning; Hoggarth to Retire, June 2025; AED is BACK on Campus!; The Greenhouse Gets a Lifeline; Acoustic Rabies Identification (ARID): A Sound-Based Approach to Rabies Testing

How The Biotic And Abiotic Factors In The Belle Forest Cave And Arboretum Soil Dictates Tree Species Prevalence, Amya A. Bingham

SPARK Symposium Presentations

A plethora of factors in the soil impact a plant’s health, including the presence of different biotic and abiotic factors. These include things like temperature, elevation, pH, microbial respiration and the presence of water, clay, loam, silt, sand, nitrogen, potassium, and phosphorus. Different soils will have varying amounts of these, which may dictate what is able to grow in them, and therefore also the surrounding area. This research project explores how the aforementioned biotic and abiotic factors affect the soil at the Belle Forest Cave and Arboretum. Three samples will be taken from four spots along a transect at this …

Eating The Fat Of The Land: The Work Of Coxiella Burnetii To Traverse Intracellular Lipid Landscapes, Charlie Porto

Theses & Dissertations

Coxiella burnetii is an obligate intracellular pathogen and the causative agent of Q fever in humans. With primary hosts in livestock ruminants, C. burnetii is endemic globally, presenting significant health risks to agricultural workers and herd health at large. Numerous wild animal reservoirs exist, increasingly threatened by expanding livestock ranges. Furthermore, with a low infectious dose through aerosol transmission, the CDC considers C. burnetii a potential bioweapon, though in humans a large amount of infections persist subclinically, occasionally progressing to pneumonia and hepatitis with chronic infections leading to endocarditis.

The parasitic life cycle of C. burnetii is biphasic, a small …

College Of Natural Sciences Newsletter, Spring 2025, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message from Dr. Sen Subramanian
Page 2 Student Spotlights
Page 3 Kaushik honored, Three-Minute Thesis, & Ice Cores revealed
Page 4 Alumni Spotlight
Page 5 Day of Scholars
Page 6 Cyanide research, Record Research Expenditures, Adhikari awarded Miller Research Award
Page 8 Hanson Receives NSF Grant
Page 9 Snow Lab Research Team
Page 10 Faculty Awards
Page 11 Drone Day
Page 13 Khalaf Awarded Presidential Award

Neutrophil Inflammatory Death Regulation By Bacterial Type Iii Secreted Effectors, Arianna D. Reuven

Dartmouth College Ph.D Dissertations

Yersinia and Pseudomonas use a T3SS to secrete effectors into host cells that inhibit phagocytosis and modulate immune responses, such as inflammasome activation. Inflammasomes promote the activation of the proinflammatory protease caspase-1. The activation of an inflammasome sensor in response to a signal or ligand initiates the assembly of the inflammasome leading to activation of caspase-1 which cleaves GSDMD and pro-inflammatory cytokines IL-1β and IL-18 into their mature forms. As neutrophils are recruited in large quantities to sites of infection, they are excellent candidates to drive inflammasome dependent responses. Neutrophils have been shown to produce multiple inflammasomes, like pyrin and …

Small-Molecule Mitotic Inhibitors As Anticancer Agents: Discovery, Classification, Mechanisms Of Action, And Clinical Trials, Yazmin Salinas, Subhash Chauhan, Debasish Bandyopadhyay

School of Medicine Publications

Despite decades of research, cancer continues to be a disease of great concern to millions of people around the world. It has been responsible for a total of 609,820 deaths in the U.S. alone in 2023. Over the years, many drugs have been developed to remove or reduce the disease’s impact, all with varying mechanisms of action and side effects. One class of these drugs is small-molecule mitotic inhibitors. These drugs inhibit cancer cell mitosis or self-replication, impeding cell proliferation and eventually leading to cell death. In this paper, small-molecule mitotic inhibitors are discussed and classified through their discovery, underlying …

Suppression Of Hypothalamic Oestrogenic Signal Sustains Hyperprolactinemia And Metabolic Adaptation In Lactating Mice, Meng Yu, Bing Feng, Jonathan C Bean, Qianru Zhao, Yongjie Yang, Hailan Liu, Yongxiang Li, Benjamin P Eappen, Hesong Liu, Longlong Tu, Kristine M Conde, Mengjie Wang, Xi Chen, Na Yin, Darah Ave Threat, Nathan Xu, Junying Han, Peiyu Gao, Yi Zhu, Darryl L Hadsell, Yang He, Pingwen Xu, Yanlin He, Chunmei Wang

Faculty, Staff and Students Publications

17β-oestradiol (E2) inhibits overeating and promotes brown adipose tissue (BAT) thermogenesis, whereas prolactin (PRL) does the opposite. During lactation, the simultaneous decline in E2 and surge in PRL contribute to maternal metabolic adaptations, including hyperphagia and suppressed BAT thermogenesis. However, the underlying neuroendocrine mechanisms remain unclear. Here, we find that oestrogen receptor alpha (ERα)-expressing neurons in the medial basal hypothalamus (MBH), specifically the arcuate nucleus of the hypothalamus and the ventrolateral subdivision of the ventromedial hypothalamus (vlVMH), are suppressed during lactation. Deletion of ERα from MBH neurons in virgin female mice induces metabolic phenotypes characteristic of lactation, including hyperprolactinemia, hyperphagia …

Il-12-Producing Cytokine Factories Induce Precursor Exhausted T Cells And Elimination Of Primary And Metastatic Tumors, Amanda Nash, Jonathon Debonis, Danna Murungi, Bertha Castillo, Boram Kim, Fangheng Hu, Courtney Chambers, Annie Nguyen, Andrea Hernandez, Zeshi Wang, Peter D Rios, Sofia Ghani, Ira Joshi, Douglas Isa, Ningbo Zheng, Weiyi Peng, Oleg A Igoshin, Jose Oberholzer, H Courtney Hodges, Nathan Reticker-Flynn, Omid Veiseh

Faculty, Staff and Students Publications

Background: Curative responses to immunotherapy require the generation of robust systemic immunity with limited toxicity. Recruitment of T cell populations such as precursor exhausted T cells (Tpex) from lymphoid tissues to tumors is a hallmark of effective treatment. However, the ability to efficiently induce this recruitment is lacking in current immunotherapy approaches. Furthermore, systemic administration of immunotherapies frequently results in dose-limiting toxicities, yielding an inadequate therapeutic window for eliciting durable responses.

Methods: In this investigation, we evaluated the safety and antitumor efficacy of locally administered interleukin 12 (IL-12) using a clinically translatable cytokine delivery platform (NCT05538624) to identify …

Single-Nucleus Transcriptional Profiling Of The Placenta Reveals The Syncytiotrophoblast Stress Response To Covid-19, Rachel A Keuls, Scott A Ochsner, Mary B O'Neill, Diana R O'Day, Akihiko Miyauchi, Kadeshia M Campbell, Natalie Lanners, Jeffery A Goldstein, Connor Yee, Neil J Mckenna, Ronald J Parchem, Jacqueline G Parchem

Faculty, Staff and Students Publications

Background: COVID-19 in pregnancy is associated with placental immune activation, inflammation, and vascular malperfusion, but its impact on syncytiotrophoblast biology and function is unclear.

Objective: This study aimed to determine the effects of maternal COVID-19 on placental syncytiotrophoblasts using single-nucleus transcriptional profiling and to compare placental stress responses in COVID-19 and preeclampsia.

Study design: For transcriptional characterization of syncytiotrophoblasts, we used the single-nucleus RNA sequencing platform, single-cell combinatorial indexing RNA sequencing (sci-RNA-seq3), to profile placental villi and fetal membranes from unvaccinated patients with symptomatic COVID-19 at birth (n = 4), gestational age-matched controls (n = 4), and a case of …

Unveiling Racial Disparities In Prostate Cancer Using An Integrative Genomic And Transcriptomic Analysis, Abdalla Elbialy, Akshay Sood, Shang-Jui Wang, Peng Wang, Ahmed Fadiel, Anil V Parwani, Steven Huang, Gennady Shvets, Nagireddy Putluri, Jenny Li, Xuefeng Liu

Faculty, Staff and Students Publications

Prostate cancer exhibits significant racial disparities, with African American (AA) individuals showing ∼64% higher incidence and 2.3 times greater mortality rates compared to their Caucasian (CA) counterparts. Understanding the complex interplay of genetic, environmental, lifestyle, socioeconomic, and healthcare access factors is crucial for developing effective interventions to reduce this disproportionate burden.

This study aims to uncover the genetic and transcriptomic differences driving these disparities through a comprehensive analysis using RNA sequencing (RNA-seq) and exome sequencing of prostate cancer tissues from both Black and White patients.

Our transcriptomics analysis revealed enhanced activity in pathways linked to immune response and cellular interactions …

Warm-Ischemia And Cold Storage Induced Modulation Of Ferroptosis Observed In Human Hearts Donated After Circulatory Death And Brain Death, Shiyi Li, Katherine V Nordick, Abdussalam E Elsenousi, Rishav Bhattacharya, Randall P Kirby, Adel M Hassan, Camila Hochman-Mendez, Todd K Rosengart, Kenneth K Liao, Nandan K Mondal

Faculty, Staff and Students Publications

We investigated ferroptosis, a type of programmed cell death mechanism, in human hearts donated after brain death (DBD) and those donated after circulatory death (DCD), focusing on warm ischemia time (WIT) and cold storage. A total of 24 hearts were procured, with six from the DBD group and 18 from the DCD group. The DCD group was divided into three subgroups, each containing six hearts, based on different WITs of 20, 40, and 60 min. All procured hearts were placed in cold storage for up to 6 h. Left ventricular biopsies were performed at 0, 2, 4, and 6 h. …

Automated Plant Morphological Assessment And Microbial Community Monitoring In Simulated Lunar Regolith, Collin R. Topolski

Doctoral Dissertations and Master's Theses

Upcoming lunar bases will need to leverage in-situ resources to ensure long-term sustainability and reduce mission costs. One key challenge is food production, which could be addressed by growing crops in lunar regolith-based substrates. However, lunar regolith lacks essential nutrients, requiring organic amendments to support continuous plant cultivation. This study examined the impact of manure-amended lunar regolith simulant on Mizuna mustard growth while assessing microbial community diversity and functionality. To support this effort, a custom software pipeline utilizing an open-source library, PlantCV, was developed to automatically track plant leaf area and height via image analysis. Results indicated that amended rhizosphere …

Host Range And Efficiency Of Plating Determination Of Phages Infecting Caulobacter And Non-Caulobacter Species, Christopher Scott

Senior Theses

Seven bacteriophages were studied to determine their host range among Caulobacter and non-Caulobacter bacteria. Recently, Caulobacter-associated phages have been shown to have broader host ranges than previously believed. Thus, it is crucial to thoroughly verify the range of bacteria strains that these phages can infect. To understand the extent of each phage’s host range, phage lysates were spotted on bacterial lawns to determine whether lysis could occur. Host-range analyses in this project conclude that these Dolichocephalovirinae phages were able to infect multiple genera and species of host bacteria. Plating efficiency experiments were also conducted to compare the phage’s …

The Isolation And Characterization Of Acidovorax And Brevundimonas Bacteriophages With Preliminary Biocontrol Study On Arabidopsis Thaliana, Minh Quynh N. Vu

Senior Theses

As antibiotic-resistance becomes an increasing global concern, researchers are looking for alternatives to combat phytopathogenic rhizobacteria – one of which is through the application of phage biocontrol. To elucidate the complex tripartite relationships between phage, bacteria and plant interactions, nine novel phages were isolated from potential phytopathogenic strains of Acidovorax (RBW13) and Brevundimonas (RBW18). These phages were isolated from root samples obtained from the Rocky Branch Creek and the Broad River located in Columbia, SC. Using Pulsed-Field Gel Electrophoresis (PFGE), we identified seven “medium sized” phages (~40 kbp), one “large-sized” phage (~200 kbp), and one “small-sized” phage ( < 25 kbp). Three phages were determined to be lambda-like due to their “ladder-building” patterns on PFGE. Although spot-tests revealed that all phages seemed to have broad host ranges that spanned over multiple genera, plaque-formations must be observed in future experiments to determine if these phages can infect their hosts productively. Preliminary in planta experiments were performed on Arabidopsis thaliana …