Cells Commons^™

Tumor Infiltrating Lymphocytes (Tils) Are A Prognosis Biomarker In Colombian Patients With Triple Negative Breast Cancer, Carlos A. Huertas-Caro, Mayra A. Ramírez, Laura Rey-Vargas, Lina María Bejarano-Rivera, Diego Felipe Ballen, Marcela Nuñez, Juan Carlos Mejía, Luz Fernanda Sua-Villegas, Alicia Cock-Rada, Jovanny Zabaleta, Laura Fejerman, María Carolina Sanabria-Salas, Silvia J. Serrano-Gomez

School of Medicine Faculty Publications

Triple negative breast cancer (TNBC) is highly immunogenic and high levels of tumor infiltrating lymphocytes (TILs) have been associated with a better prognosis and higher probability to achieve pathological complete response. Here, we explore the potential role of stromal TILs level and composition as a prognostic and predictive biomarker in TNBC. 195 Tumor biospecimens from patients diagnosed with TNBC were included. Stromal TILs (sTILs), positive CD4/CD8 cells were evaluated. Differences in clinic-pathological characteristics according to immune infiltration were assessed. The predictive and prognostic value of immune infiltration was analyzed by multivariate models. Higher immune infiltration was observed in patients with …

The Implications Of Ferroptosis In Antibiotic Resistance, Marysol Hohl

Senior Honors Theses

Bacterial infections in the United States are becoming increasingly resistant to existing antibiotic treatments. Due to projected increases in resistance and the recent decrease in novel antibacterials, experts have determined that the United States is in the “post-antibiotic era.” The scientific community has failed to resolve resistance despite the continual discovery of new antibiotic compounds. In the past decade, a novel form of cell death called ferroptosis has been implicated in antibiotic treatment by employing the use of nanotechnology. This literature review will describe the problem of bacterial resistance and demonstrate how current research is pioneering a new age of …

A Neurodevelopmental Perspective To Improve Innovation In Preventive Treatment Of Substance Use Disorders, Ismael Perez, John Vandeberg, Mario Gil

Research Symposium

Background: Midbrain dopaminergic neurons have been associated with substance use disorders (Blaess & Ang, 2015). Understanding their neurodevelopment during early stages of life is fundamental for innovating preventive care treatments. The animal model Monodelphis domestica has been proposed as an excellent candidate to study neurodevelopmental changes due to the ease of access to see changes in their embryonic development (Mate et al., 1994). The purpose of our study is to inform how brain cells, including and especially dopaminergic neurons, mature by quantifying their number during early development. Additionally, the study aims to compare different midbrain areas and track neurodevelopmental changes …

Anti-Inflammatory And Antioxidant Effects Of Sea Urchin Spine Extract, Dina Magdy El Gamal

The Undergraduate Research Journal

Diadema savignyi spine extract in an experimental setup using L929 cell line in vitro. The cell metabolic activity of L929 cells is tested through an MTT assay. The sea urchin spine extract is applied to the cells in two concentrations: 100 μg/ml (136% viability) and 200 μg/ml (95% viability). The bioactive components of the sea urchin spine are identified via GC-MS, and the antioxidant and anti-inflammatory activities are evaluated using catalase assay (CAT), glutathione (GSH), and nitric oxide (NO) tests. Results show that the GC-MS identified bioactive components including the anti-inflammatory and anti-irritant bisabolol oxide and the pro-inflammatory oleic acid. …

Candida-Induced Granulocytic Myeloid-Derived Suppressor Cells Are Protective Against Polymicrobial Sepsis, Shannon Esher Righi, Amanda J. Harriett, Elizabeth A. Lilly, Paul L. Fidel Jr., Mairi C. Noverr

School of Dentistry Faculty Publications

Polymicrobial intra-abdominal infections (IAI) can lead to life-threatening sepsis with significant morbidity and mortality, especially when pathogenic fungi are involved. We have employed an established clinically relevant mouse model of fungal/bacterial IAI and shown that immunization with low-virulence Candida species, that is, Candida dubliniensis, can induce responses that protect against sepsis via the suppression of lethal inflammation. This protection is dependent on long-lived Gr-1(+) polymorphonuclear leukocytes that display characteristics consistent with myeloid-derived suppressor cells (MDSCs) and trained innate immunity. Here we aimed to functionally and phenotypically characterize these protective Gr-1(+) leukocytes. Compared to nonimmunized control mice, we observed increased levels …

Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke

Electronic Theses and Dissertations

The number of daily bacterial infections is climbing and the CDC explains that this is due to the antibiotic-resistant threat in the United States. Finding a faster way of bacterial identification is necessary as it currently takes 1-4 days for a medical lab to culture and identify bacteria. Photoacoustic flow cytometry (PAFC) can be used as an alternative method resulting in swift identification within an hour (Edgar, 2019). Pseudomonas aeruginosa, cell line PA01, will be coated in up to a few hundred red dyed phages making it detectible by the photoacoustic flow cytometry system. Bacteriophages (phages) are viruses that …

Targeting Cgas/Sting Signaling-Mediated Myeloid Immune Cell Dysfunction In Time, Vijay Kumar, Caitlin Bauer, John H. Stewart

School of Graduate Studies Faculty Publications

Myeloid immune cells (MICs) are potent innate immune cells serving as first responders to invading pathogens and internal changes to cellular homeostasis. Cancer is a stage of altered cellular homeostasis that can originate in response to different pathogens, chemical carcinogens, and internal genetic/epigenetic changes. MICs express several pattern recognition receptors (PRRs) on their membranes, cytosol, and organelles, recognizing systemic, tissue, and organ-specific altered homeostasis. cGAS/STING signaling is a cytosolic PRR system for identifying cytosolic double-stranded DNA (dsDNA) in a sequence-independent but size-dependent manner. The longer the cytosolic dsDNA size, the stronger the cGAS/STING signaling activation with increased type 1 interferon …

Systemic Review Of Clot Retraction Modulators, Alaina Guilbeau, Rinku Majumder

School of Graduate Studies Faculty Publications

Through a process termed clot retraction, platelets cause thrombi to shrink and become more stable. After platelets are activated via inside-out signaling, glycoprotein αIIbβIII binds to fibrinogen and initiates a cascade of intracellular signaling that ends in actin remodeling, which causes the platelet to change its shape. Clot retraction is also important for wound healing. Although the detailed molecular biology of clot retraction is only partially understood, various substances and physiological conditions modulate clot retraction. In this review, we describe some of the current literature pertaining to clot retraction modulators. In addition, we discuss compounds from Cudrania trucuspidata, Arctium lappa, …

Incubation With Porcine Urinary Bladder Matrix Yields A Late-Stage Wound Transcriptome In Endothelial Cells And Keratinocytes Isolated From Both Diabetic And Non-Diabetic Subjects, John T. Paige, Daniel J. Lightell, Hunter F. Douglas, Natasha C. Klingenberg, Thaidan Pham, T. Cooper Woods

School of Medicine Faculty Publications

Proper wound closure requires the functional coordination of endothelial cells (ECs) and keratinocytes. In the late stages of wound healing, keratinocytes become activated and ECs promote the maturation of nascent blood vessels. In diabetes mellitus, decreased keratinocyte activation and impaired angiogenic action of ECs delay wound healing. Porcine urinary bladder matrix (UBM) improves the rate of wound healing, but the effect of exposure to UBM under diabetic conditions remains unclear. We hypothesized that keratinocytes and ECs isolated from both diabetic and non-diabetic donors would exhibit a similar transcriptome representative of the later stages of wound healing following incubation with UBM. …

Tumor Microenvironment As A Therapeutic Target In Melanoma Treatment, Naji Kharouf, Thomas W. Flanagan, Sofie Yasmin Hassan, Hosam Shalaby, Marla Khabaz, Sarah Lilly Hassan, Mosaad Megahed, Youssef Haikel, Simeon Santourlidis, Mohamed Hassan

School of Graduate Studies Faculty Publications

The role of the tumor microenvironment in tumor growth and therapy has recently attracted more attention in research and drug development. The ability of the microenvironment to trigger tumor maintenance, progression, and resistance is the main cause for treatment failure and tumor relapse. Accumulated evidence indicates that the maintenance and progression of tumor cells is determined by components of the microenvironment, which include stromal cells (endothelial cells, fibroblasts, mesenchymal stem cells, and immune cells), extracellular matrix (ECM), and soluble molecules (chemokines, cytokines, growth factors, and extracellular vesicles). As a solid tumor, melanoma is not only a tumor mass of monolithic …

Control Of The Electroporation Efficiency Of Nanosecond Pulses By Swinging The Electric Field Vector Direction, Vitalii Kim, Iurii Semenov, Allen S. Kiester, Mark A. Keppler, Bennett L. Ibey, Joel N. Bixler, Ruben M. L. Colunga Biancatelli, Andrei G. Pakhomov

Bioelectrics Publications

Reversing the pulse polarity, i.e., changing the electric field direction by 180°, inhibits electroporation and electrostimulation by nanosecond electric pulses (nsEPs). This feature, known as “bipolar cancellation,” enables selective remote targeting with nsEPs and reduces the neuromuscular side effects of ablation therapies. We analyzed the biophysical mechanisms and measured how cancellation weakens and is replaced by facilitation when nsEPs are applied from different directions at angles from 0 to 180°. Monolayers of endothelial cells were electroporated by a train of five pulses (600 ns) or five paired pulses (600 + 600 ns) applied at 1 Hz or 833 kHz. Reversing …

Investigating Sexual Dimorphism In Lateral Hypothalamic Melanin-Concentrating Hormone Neuron Subpopulations, Mahitha Juttu

Honors Scholar Theses

The lateral hypothalamic area (LHA) is an area crucial for coordinating key behaviors such as sleep, wakefulness, stress, and feeding. Within this area in the brain, Melanin concentrating hormone (MCH) neurons are exclusive to the LHA and also contribute to these key homeostatic behaviors. These neurons can be divided into two different subpopulations: MCH neurons that express cocaine amphetamine-regulated transcript (CART) tachykinin-3 receptor (NK3R) and MCH neurons that do not express CART and NK3R. These neuronal subpopulations have been implicated in coordinating key behaviors but have not been well studied.

In this paper, our project seeks to analyze how the …

Dpp8 Selective Inhibitor Tominostat As A Novel And Broad-Spectrum Anticancer Agent Against Hematological Malignancies, Shohei Kikuchi, Akinori Wada, Yusuke Kamihara, Kosuke Okazaki, Paras Jawaid, Mati Ur Rehman, Eiji Kobayashi, Takeshi Susukida, Tomoki Minemura, Yoshimi Nabe

Department of Biological & Biomedical Sciences

DPP8/9 inhibition induces either pyroptotic or apoptotic cell death in hematological malignancies. We previously reported that treatment with the DPP8/9 inhibitor 1G244 resulted in apoptotic cell death in myeloma, and our current study further evaluates the mechanism of action of 1G244 in different blood cancer cell lines. Specifically, 1G244 inhibited DPP9 to induce GSDMD-mediated-pyroptosis at low concentrations and inhibited DPP8 to cause caspase-3-mediated-apoptosis at high concentrations. HCK expression is necessary to induce susceptibility to pyroptosis but does not participate in the induction of apoptosis. To further characterize this DPP8-dependent broad-spectrum apoptosis induction effect, we evaluated the potential antineoplastic role for …

Moerv14 Mediates The Intracellular Transport Of Cell Membrane Receptors To Govern The Appressorial Formation And Pathogenicity Of Magnaporthe Oryzae, Bin Qian, Xiaotong Su, Ziyuan Ye, Xinyu Liu, Muxing Liu, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Graduate Studies Faculty Publications

Magnaporthe oryzae causes rice blasts posing serious threats to food security worldwide. During infection, M. oryzae utilizes several transmembrane receptor proteins that sense cell surface cues to induce highly specialized infectious structures called appressoria. However, little is known about the mechanisms of intracellular receptor tracking and their function. Here, we described that disrupting the coat protein complex II (COPII) cargo protein MoErv14 severely affects appressorium formation and pathogenicity as the ΔMoerv14 mutant is defective not only in cAMP production but also in the phosphorylation of the mitogen-activated protein kinase (MAPK) MoPmk1. Studies also showed that either externally supplementing cAMP or …

Triazole Compounds – Potentials In The Treatment Of Cystic Fibrosis, Maggie Taylor

Undergraduate Research Conference

Cystic Fibrosis (CF) is a genetic disease that affects the respiratory and digestive system and is most common among Caucasians of Northern European origin. CF is caused by mutations in a membrane protein CFTR (Cystic Fibrosis Transmembrane-conductance Regulator). This mutation impairs the membrane protein’s chloride ion channel function. One of the most common CFTR mutations is the DF508 mutation that affects over 70% of CF cases. Our research has shown that the DF508-CFTR mutation can be partially reversed by physical and chemical means [Heda & Marino, BBRC, 271:659-664, 2000]. In cell lines expressing DF508-CFTR, synthetic anion carriers have shown to …

Enhanced Ca2+-Channeling Complex Formation At The Er-Mitochondria Interface Underlies The Pathogenesis Of Alcohol-Associated Liver Disease, Themis Thoudam, Dipanjan Chanda, Jung Yi Lee, Min Kyo Jung, Ibotombi Singh Sinam, Byung Gyu Kim, Bo Yoon Park, Woong Hee Kwon, Hyo Jeong Kim, Myeongjin Kim, Chae Won Lim, Hoyul Lee, Yang Hoon Huh, Caroline A. Miller, Romil Saxena, Nicholas J. Skill, Nazmul Huda, Praveen Kusumanchi, Jing Ma, Zhihong Yang, Min Ji Kim, Ji Young Mun, Robert A. Harris, Jae Han Jeon, Suthat Liangpunsakul, In Kyu Lee

School of Medicine Faculty Publications

Ca2+ overload-induced mitochondrial dysfunction is considered as a major contributing factor in the pathogenesis of alcohol-associated liver disease (ALD). However, the initiating factors that drive mitochondrial Ca2+ accumulation in ALD remain elusive. Here, we demonstrate that an aberrant increase in hepatic GRP75-mediated mitochondria-associated ER membrane (MAM) Ca2+-channeling (MCC) complex formation promotes mitochondrial dysfunction in vitro and in male mouse model of ALD. Unbiased transcriptomic analysis reveals PDK4 as a prominently inducible MAM kinase in ALD. Analysis of human ALD cohorts further corroborate these findings. Additional mass spectrometry analysis unveils GRP75 as a downstream phosphorylation target of PDK4. Conversely, non-phosphorylatable GRP75 …

Lipoprotein(A) In Atherosclerotic Cardiovascular Disease And Aortic Stenosis: A European Atherosclerosis Society Consensus Statement, Florian Kronenberg, Samia Mora, Erik S G Stroes, Brian Ference Ference Ference, Benoit J. Arsenault, Lars Berglund, Marc R. Dweck, Marlys Koschinsky, Gilles Lambert, Salim S. Virani

Office of the Provost

This 2022 European Atherosclerosis Society lipoprotein(a) [Lp(a)] consensus statement updates evidence for the role of Lp(a) in atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis, provides clinical guidance for testing and treating elevated Lp(a) levels, and considers its inclusion in global risk estimation. Epidemiologic and genetic studies involving hundreds of thousands of individuals strongly support a causal and continuous association between Lp(a) concentration and cardiovascular outcomes in different ethnicities; elevated Lp(a) is a risk factor even at very low levels of low-density lipoprotein cholesterol. High Lp(a) is associated with both microcalcification and macrocalcification of the aortic valve. Current findings do …

H2s, Sg-1002, Protects Against Myocardial Oxidative Damage And Hypertrophy In Vitro Via Induction Of Cystathionine Β-Synthase And Antioxidant Proteins, Rahib K. Islam, Erinn Donnelly, Erminia Donnarumma, Fokhrul Hossain, Jason D. Gardner, Kazi N. Islam

School of Medicine Faculty Publications

Endogenously produced hydrogen sulfide (H2S) is critical for cardiovascular homeostasis. Therapeutic strategies aimed at increasing H2S levels have proven cardioprotective in models of acute myocardial infarction (MI) and heart failure (HF). The present study was undertaken to investigate the effects of a novel H2S prodrug, SG-1002, on stress induced hypertrophic signaling in murine HL-1 cardiac muscle cells. Treatment of HL-1 cells with SG-1002 under serum starvation without or with H2O2 increased the levels of H2S, H2S producing enzyme, and cystathionine β-synthase (CBS), as well as antioxidant protein levels, such as super oxide dismutase1 (SOD1) and catalase, and additionally decreased oxidative …

Quitting Smoking After A Cancer Diagnosis Is Associated With High-Risk Neutrophil-To-Lymphocyte Ratio Among Tobacco Use-Related Cancer Survivors, You Lu, Katherine Kwong, James Wells, Andrea Edwards, Zhong Chen, Tung-Sung Tseng, Kun Zhang

School of Public Health Faculty Publications

Quitting smoking could potentially minimize the risk of a high neutrophil-to-lymphocyte ratio (NLR) among tobacco use-related (TUR) cancer survivors. A total of 1263 TUR cancer survivors aged 20 to 85 years old were investigated using data from the National Health and Nutritional Examination Survey 1999-2018. The primary outcome was the NLR, which was defined as having two levels: high-risk (≥ 3) and low-risk (< 3). The association between smoking cessation time and a high-risk NLR level was analyzed using weighted logistic regression models. Overall, the current smoking rate of TUR cancer survivors was found to be 21.7%. Older age (75 years above), gender and respiratory-related cancers are covariables associated with high risk of NLR levels for individual who identified as Non-Hispanic White (NHW). Non-Hispanic Black (NHB) (n = 27) who quit smoking after a cancer diagnosis were associated with the highest risk of a high NLR (OR 4.83, 95% CI 1.40-16.61, p = 0.01) compared to NHB nonsmokers (n = 139). These findings suggest that the risk of a high NLR level is strongly associated with the time of smoking cessation in NHB TUR cancer survivors. As a result, NHB TUR cancer survivors should quit smoking as soon as possible because the benefits of quitting smoking were observed over the 5 year period following smoking cessation.

Frequency Of Von Willebrand Disease And Its Types: Data From A Tertiary Care Hospital Of Karachi, Pakistan, Jyoti Mohan Lal, Anila Rashid, Natasha Ali

Department of Pathology and Laboratory Medicine

Introduction: von Willebrand disease is the most common inherited bleeding disorder. It is classified into 3 main types, type I and III are quantitative defects whereas type II is qualitative defect which is further sub-classified in to II-A, II-B, II-M, II-N. The aim of the present study is to see frequency and types of von Willebrand disease in a tertiary care hospital of Karachi, Pakistan.
Materials and methods: This retrospective cross-sectional study was conducted in the section of Hematology and Transfusion Medicine, Department of Pathology and Laboratory Medicine, the Aga Khan University hospital, Karachi, from May 2020 to April 2021 …

Inhibition Of Ribosome Assembly Factor Pno1 By Crispr/Cas9 Technique Suppresses Lung Adenocarcinoma And Notch Pathway: Clinical Application, Sanjit K. Roy, Shivam Srivastava, Andrew Hancock, Anju Shrivastava, Jason Morvant, Sharmila Shankar, Rakesh K. Srivastava

School of Medicine Faculty Publications

Growth is crucially controlled by the functional ribosomes available in cells. To meet the enhanced energy demand, cancer cells re-wire and increase their ribosome biogenesis. The RNA-binding protein PNO1, a ribosome assembly factor, plays an essential role in ribosome biogenesis. The purpose of this study was to examine whether PNO1 can be used as a biomarker for lung adenocarcinoma and also examine the molecular mechanisms by which PNO1 knockdown by CRISPR/Cas9 inhibited growth and epithelial–mesenchymal transition (EMT). The expression of PNO1 was significantly higher in lung adenocarcinoma compared to normal lung tissues. PNO1 expression in lung adenocarcinoma patients increased with …

Relationship Of Abdominal Circumference And Trunk Length With Spinal Anesthesia Block Height In Geriatric Patients Undergoing Transurethral Resection Of Prostate, Muhammad Yahya, Aliya Ahmed, Iayla Fatima, Muhammad Nasir

Department of Anaesthesia

Introduction: Spinal anesthesia is commonly used for various surgical procedures. Prediction of spinal anesthesia block height is always a challenging task for anesthetists. Higher than desired levels of spinal anesthesia blocks are associated with serious side effects, while inadequate block height does not provide satisfactory surgical anesthesia. In this study, we observed the relationship between the ratio of trunk length (TL) and square of the abdominal circumference (AC²) and spinal anesthesia sensory block height in geriatric patients undergoing transurethral resection of the prostate (TURP).
Material & Methods: This is a cross-sectional study conducted at the Aga Khan University …

Testicular Choriocarcinoma With Small Bowel Metastasis And Active Gastrointestinal Bleeding, Asad Saulat Fatimi, Khizer Masroor Anns, Faheemullah Khan, Wasim Ahmed Memon, Junaid Iqbal, Muhammad Aman, Izaz Ahmad, Sahar Fatima

Medical College Documents

Testicular choriocarcinomas make up less than 1% of all germ-cell tumors and are highly malignant, attributable to hematogenous spread. While the most common sites of metastasis are the lungs and liver, metastatic spread to the gastrointestinal tract is rare wherein patients may present with GI distress or even an upper GI bleed. In this report, we present a case of known testicular choriocarcinoma in a 40-year-old male who presented to the emergency room with severe anemia and a suspected upper GI bleed.

Combined 3d Bioprinting And Tissue-Specific Ecm System Reveals The Influence Of Brain Matrix On Stem Cell Differentiation, Martina Zamponi, Peter A. Mollica, Yara Khodour, Julie S. Bjerring, Robert D. Bruno, Patrick C. Sachs

School of Medical Diagnostics & Translational Sciences Publications

We have previously shown that human and murine breast extracellular matrix (ECM) can significantly impact cellular behavior, including stem cell fate determination. It has been established that tissue-specific extracellular matrix from the central nervous system has the capacity to support neuronal survival. However, the characterization of its influence on stem cell differentiation and its adaptation to robust 3D culture models is underdeveloped. To address these issues, we combined our 3D bioprinter with hydrogels containing porcine brain extracellular matrix (BMX) to test the influence of the extracellular matrix on stem cell differentiation. Our 3D bioprinting system generated reproducible 3D neural structures …

Gene Expression Under Combined Hypoxia And Acidosis In Chondrosarcoma, Michael Stacey, Kostika Vangjeli, Christopher Osgood

Bioelectrics Publications

Chondrosarcomas are the second most common cause of bone cancer and are removed surgically with wide margins. On recurrence, they are resistant to chemo and radiation therapy and new treatment options are critically required. This tumor type produces hyaline cartilage, a cartilage normally formed under hypoxic and acidic environment due to lack of vasculature in cartilage. Paradoxically, chondrosarcomas arise in the well vascularized, oxygen rich environment of the bone. Hypoxia and acidosis are two stressors where the cellular effects are typically reported separately even though cells experience combined effects of hypoxia and acidosis. Given the mechanistic links between hypoxia and …

Interactions Of Carboxylated Nanodiamonds With Mouse Macrophages Cell Line And Primary Cells, Maisoun Bani-Hani, Stephen J. Beebe, Michael W. Stacey, Christopher Osgood

Bioelectrics Publications

Nanodiamonds (ND) have attracted significant interest for their use in several biomedical applications. These applications can be very useful if the safety and compatibility of ND are proven. We assessed the effects of ND (100 nm, Carboxylated) on primary macrophages and a macrophage-like cell line and found that these particles are not toxic to these cells at lower concentrations but may interfere with cell functions and differentiation. Internalization of ND by these cells in a time- and dose-dependent manner was mostly via phagocytosis and clathrin-dependent endocytosis and localized to the cytoplasm but not into the nucleus. No significant induction of …

Pulsed Electric Field Ablation Of Esophageal Malignancies And Mitigating Damage To Smooth Muscle: An In Vitro Study, Emily Gudvangen, Uma Mangalanathan, Iurii Semenov, Allen S. Kiester, Mark A. Keppler, Bennett L. Ibey, Joel N. Bixler, Andrei G. Pakhomov

Bioelectrics Publications

Cancer ablation therapies aim to be efficient while minimizing damage to healthy tissues. Nanosecond pulsed electric field (nsPEF) is a promising ablation modality because of its selectivity against certain cell types and reduced neuromuscular effects. We compared cell killing efficiency by PEF (100 pulses, 200 ns–10 µs duration, 10 Hz) in a panel of human esophageal cells (normal and pre-malignant epithelial and smooth muscle). Normal epithelial cells were less sensitive than the pre-malignant ones to unipolar PEF (15–20% higher LD50, p < 0.05). Smooth muscle cells (SMC) oriented randomly in the electric field were more sensitive, with 30–40% lower LD50 (p < 0.01). Trains of ten, 300-ns pulses at 10 kV/cm caused twofold weaker electroporative uptake of YO-PRO-1 dye in normal epithelial cells than in either pre-malignant cells or in SMC oriented perpendicularly to the field. Aligning SMC with the field reduced the dye uptake fourfold, along with a twofold reduction in Ca²⁺ transients. A 300-ns pulse induced a twofold smaller transmembrane potential in cells aligned with the field, making them …

Sound The (Smaller) Alarm: The Triphosphate Magic Spot Nucleotide Pgpp, Areej Malik, Megan A. Hept, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

It has recently become evident that the bacterial stringent response is regulated by a triphosphate alarmone (pGpp) as well as the canonical tetra- and pentaphosphate alarmones ppGpp and pppGpp [together, (p)ppGpp]. Often dismissed in the past as an artifact or degradation product, pGpp has been confirmed as a deliberate endpoint of multiple synthetic pathways utilizing GMP, (p)ppGpp, or GDP/GTP as precursors. Some early studies concluded that pGpp functionally mimics (p)ppGpp and that its biological role is to make alarmone metabolism less dependent on the guanine energy charge of the cell by allowing GMP-dependent synthesis to continue when GDP/GTP has been …

Integrating Shear Flow And Trypsin Treatment To Assess Cell Adhesion Strength, Antra Patel, Bhavana Bhavanam, Trevor Keenan, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Cell adhesion is of fundamental importance in cell and tissue organization and for designing cell-laden constructs for tissue engineering. Prior methods to assess cell adhesion strength for strongly adherent cells using hydrodynamic shear flow either involved the use of specialized flow devices to generate high shear stress or used simpler implementations like larger height parallel plate chambers that enable multihour cell culture but generate low wall shear stress and are, hence, more applicable for weakly adherent cells. Here, we propose a shear flow assay for adhesion strength assessment of strongly adherent cells that employs off-the-shelf parallel plate chambers for shear …

Enhancing The Conformational Stability Of The Cl-Par-4 Tumor Suppressor Via Site-Directed Mutagenesis, Samjhana Pandey, Krishna K. Raut, Antoine Baudin, Lamya Djemri, David S. Libich, Komala Ponniah, Steven M. Pascal

Chemistry & Biochemistry Faculty Publications

Intrinsically disordered proteins play important roles in cell signaling, and dysregulation of these proteins is associated with several diseases. Prostate apoptosis response-4 (Par-4), an approximately 40 kilodalton proapoptotic tumor suppressor, is a predominantly intrinsically disordered protein whose downregulation has been observed in various cancers. The caspase-cleaved fragment of Par-4 (cl-Par-4) is active and plays a role in tumor suppression by inhibiting cell survival pathways. Here, we employed site-directed mutagenesis to create a cl-Par-4 point mutant (D313K). The expressed and purified D313K protein was characterized using biophysical techniques, and the results were compared to that of the wild-type (WT). We have …