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Articles 91 - 120 of 575

Full-Text Articles in Biology

Inhibiting Glutamine Utilization Creates A Synthetic Lethality For Suppression Of Atp Citrate Lyase In Kras-Driven Cancer Cells, Ahmet Hatipoglu, Deepak Menon, Talia Levy, Maria A. Frias, David A. Foster Oct 2022

Inhibiting Glutamine Utilization Creates A Synthetic Lethality For Suppression Of Atp Citrate Lyase In Kras-Driven Cancer Cells, Ahmet Hatipoglu, Deepak Menon, Talia Levy, Maria A. Frias, David A. Foster

Publications and Research

Metabolic reprogramming is now considered a hallmark of cancer cells. KRas-driven cancer cells use glutaminolysis to generate the tricarboxylic acid cycle intermediate α -ketoglutarate via a transamination reaction between glutamate and oxaloacetate. We reported previously that exogenously supplied unsaturated fatty acids could be used to synthesize phosphatidic acid–a lipid second messenger that activates both mammalian target of rapamycin (mTOR) complex 1 (mTORC1) and mTOR complex 2 (mTORC2). A key target of mTORC2 is Akt–a kinase that promotes survival and regulates cell metabolism. We report here that mono- unsaturated oleic acid stimulates the phosphoryla tion of ATP citrate lyase (ACLY) at …


Function Of Atm And Msh2 During Dna Repair And Recombination, Emily Sible Sep 2022

Function Of Atm And Msh2 During Dna Repair And Recombination, Emily Sible

Dissertations, Theses, and Capstone Projects

Class switch recombination (CSR) produces secondary immunoglobulin isotypes and requires AID-dependent DNA deamination of intronic switch (S) regions within the immunoglobulin heavy chain (Igh) gene locus. Non-canonical repair of deaminated DNA by mismatch repair (MMR) or base excision repair (BER) creates DNA breaks that permit recombination between distal S regions. ATM-dependent phosphorylation of AID at serine-38 (pS38-AID) promotes its interaction with APE1, a BER protein, suggesting that ATM regulates CSR through BER. However, pS38-AID may also function in MMR during CSR, although the mechanism remains unknown. To examine whether ATM modulates BER- and/or MMR-dependent CSR, Atm-/- mice …


Gamma Protocadherin Synaptic Localization And Intracellular Trafficking Is Consistent With Distinct Adhesive And Anti-Adhesive Roles In Development, Nicole Lamassa Sep 2022

Gamma Protocadherin Synaptic Localization And Intracellular Trafficking Is Consistent With Distinct Adhesive And Anti-Adhesive Roles In Development, Nicole Lamassa

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) constitute a family of cell adhesion molecules with approximately 60 Pcdh genes clustered in a 1 MB locus on chromosome 5q31 in humans. The Pcdh gene cluster is subdivided into α, β, and γ subclusters which encode related proteins. Individual neurons activate different subsets of Pcdh-α, Pcdh-β and Pcdh-γ genes by epigenetic mechanisms to generate distinct Pcdh adhesive units expressed by each neuron. This is thought to serve as a “surface barcode” for single-cell identity and synaptic recognition in the nervous system. The actual role for Pcdhs in neural development is still relatively unknown and different roles …


Generation Of Mycobacterium Smegmatis Model Systems For Testing Inhibitors Of The Mycobactin Siderophore Of Mycobacterium Tuberculosis, Gabrielle A. Germain Sep 2022

Generation Of Mycobacterium Smegmatis Model Systems For Testing Inhibitors Of The Mycobactin Siderophore Of Mycobacterium Tuberculosis, Gabrielle A. Germain

Dissertations, Theses, and Capstone Projects

Mycobacterium tuberculosis (Mtb) is the pathogenic bacterium causative of tuberculosis. According to the 2021 World Health Organization (WHO) Global Tuberculosis (TB) Report, there were approximately 5.8 million TB cases in 2020, and 1.3 million TB deaths among HIV negative people in that year. The rise of multi-drug resistant Mtb strains has increased the need for more potent microbials against this pathogen. Biosynthesis of iron scavenging molecules, known as siderophores (e.g., mycobactin and carboxymycobactin), has been identified as a potential drug target candidate since iron acquisition has been directly linked to the survival and virulence of Mtb. Salicyl-AMS (Sal-AMS) is …


Role Of The G Protein Beta Gamma Subunits In Serotonin Transporter Dynamics, Nora Awadallah Sep 2022

Role Of The G Protein Beta Gamma Subunits In Serotonin Transporter Dynamics, Nora Awadallah

Dissertations, Theses, and Capstone Projects

Serotonin is a vital neurotransmitter and hormone with significant roles in almost every organ system. In the central nervous system, serotonin mediates physiological functions that in turn guide behavior and mood. Here, serotonin is released from serotonergic neurons and exerts its effects through serotonin receptors. Regulation of serotonin neurotransmission is important for the maintenance of its physiological functions; thus, extracellular serotonin must be sequestered to limit the intensity and duration of serotonin transmission. Disproportionate transmission is strongly linked with neurological and psychiatric ailments.

Extracellular serotonin levels are primarily mediated by the serotonin transporter (SERT), a critically important plasma membrane protein …


Genetic Determinants Of Carotenoid Pigmentation In The Opportunistic Pathogen Mycobacterium Kansasii, Niklas Janisch Sep 2022

Genetic Determinants Of Carotenoid Pigmentation In The Opportunistic Pathogen Mycobacterium Kansasii, Niklas Janisch

Dissertations, Theses, and Capstone Projects

Mycobacterium kansasii (Mk) is an opportunistic pulmonary pathogen causing infections, predominantly in immunocompromised people, with symptoms similar to those caused by its close relative Mycobacterium tuberculosis (Mt). In contrast to the latter, little work has been done on Mk genetics and even less on its defining characteristic of photochromogenicity, the controlled expression of carotenoid pigments in response to light exposure.

This work represents major progress in the investigation of pigmentation-related genetic factors in Mk. We report the creation of a large-scale, random transposon-insertion mutant library of Mk and its subsequent screening for mutants with an aberration in the …


Clustered Protocadherins Ubiquitination And Phosphorylation Regulates Surface Expression, Albert Ptashnik Sep 2022

Clustered Protocadherins Ubiquitination And Phosphorylation Regulates Surface Expression, Albert Ptashnik

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) are a family of 60 adhesion-like molecules forming a neural barcode. In vertebrate neurons, 60 Pcdhs are coded by a large gene cluster. Numerous axons in the cluster are coding for the different extracellular, transmembrane, variable portion of the cytoplasmic and constant cytoplasmic domains where their expression is controlled epigenetically. These proteins mediate interactions between axons, dendrites, and glial cells during neural development. Yet, Pcdhs are not strictly adhesion molecules. In the amacrine cells of the retina, Pcdhs promote avoidance of the same cell dendrites, where in the cortex Pcdhs promote interactions between dendrites and astrocytes. In …


Nup211 Plays An Important Role In Regulating Mrna Export And Stress Response, Ayana Ikenouchi Aug 2022

Nup211 Plays An Important Role In Regulating Mrna Export And Stress Response, Ayana Ikenouchi

Theses and Dissertations

Nup211 is a nuclear pore basket component in Schizosaccharomyces pombe and roles in the gating functions of NPCs. Using RT-qPCR, I found that in nup211-shutoff cells, the transcript levels of genes in mRNA export and stress-response pathways were significantly changed, suggesting nup211 is involved in regulating stress response pathways.


Intermediates In Sars-Cov-2 Spike–Mediated Cell Entry, Tara C. Marcink, Thomas Kicmal, Emily Armbruster, Zhening Zhang, Gillian Zipursky, Kate L. Golub, Mohab Idris, Jonathan Khao, Jennifer Drew-Bear, Gael Mcgill, Tom Gallagher, Matteo Porotto, Amédée Des Georges, Anne Moscona Aug 2022

Intermediates In Sars-Cov-2 Spike–Mediated Cell Entry, Tara C. Marcink, Thomas Kicmal, Emily Armbruster, Zhening Zhang, Gillian Zipursky, Kate L. Golub, Mohab Idris, Jonathan Khao, Jennifer Drew-Bear, Gael Mcgill, Tom Gallagher, Matteo Porotto, Amédée Des Georges, Anne Moscona

Advanced Science Research Center

SARS-CoV-2 cell entry is completed after viral spike (S) protein–mediated membrane fusion between viral and host cell membranes. Stable prefusion and postfusion S structures have been resolved by cryo–electron microscopy and cryo–electron tomography, but the refolding intermediates on the fusion pathway are transient and have not been examined. We used an antiviral lipopeptide entry inhibitor to arrest S protein refolding and thereby capture intermediates as S proteins interact with hACE2 and fusion-activating proteases on cell-derived target membranes. Cryo–electron tomography imaged both extended and partially folded intermediate states of S2, as well as a novel late-stage conformation on the pathway to …


Mtorc1 And Mtorc2 Complexes Regulate The Untargeted Metabolomics And Amino Acid Metabolites Profile Through Mitochondrial Bioenergetic Functions In Pancreatic Beta Cells, Ghada A. Soliman, Rinat Abzalimov, Ye He Jul 2022

Mtorc1 And Mtorc2 Complexes Regulate The Untargeted Metabolomics And Amino Acid Metabolites Profile Through Mitochondrial Bioenergetic Functions In Pancreatic Beta Cells, Ghada A. Soliman, Rinat Abzalimov, Ye He

Advanced Science Research Center

Background: Pancreatic beta cells regulate bioenergetics efficiency and secret insulin in response to glucose and nutrient availability. The mechanistic Target of Rapamycin (mTOR) network orchestrates pancreatic progenitor cell growth and metabolism by nucleating two complexes, mTORC1 and mTORC2. Objective: To determine the impact of mTORC1/mTORC2 inhibition on amino acid metabolism in mouse pancreatic beta cells (Beta-TC-6 cells, ATCC-CRL-11506) using high-resolution metabolomics (HRM) and live-mitochondrial functions. Methods: Pancreatic beta TC-6 cells were incubated for 24 h with either: RapaLink-1 (RL); Torin-2 (T); rapamycin (R); metformin (M); a combination of RapaLink-1 and metformin (RLM); Torin-2 and metformin (TM); compared to the control. …


The Molecular Mechanism Of Load Adaptation By Branched Actin Networks, Tai-De Li, Peter Bieling, Julian Weichsel, R Dyche Mullins, Daniel A. Fletcher Jun 2022

The Molecular Mechanism Of Load Adaptation By Branched Actin Networks, Tai-De Li, Peter Bieling, Julian Weichsel, R Dyche Mullins, Daniel A. Fletcher

Advanced Science Research Center

Branched actin networks are self-assembling molecular motors that move biological membranes and drive many important cellular processes, including phagocytosis, endocytosis, and pseudopod protrusion. When confronted with opposing forces, the growth rate of these networks slows and their density increases, but the stoichiometry of key components does not change. The molecular mechanisms governing this force response are not well understood, so we used single-molecule imaging and AFM cantilever deflection to measure how applied forces affect each step in branched actin network assembly. Although load forces are observed to increase the density of growing filaments, we find that they actually decrease the …


Biological Factors Affecting Dna Shedding Propensity, Ines G. Cedillo-Cruz Jun 2022

Biological Factors Affecting Dna Shedding Propensity, Ines G. Cedillo-Cruz

Student Theses

Recovery of trace DNA is important in forensic casework because it is the main type of biological evidence found in both violent and non-violent crimes. Researchers have been trying to determine if there are individual differences in shedding propensity, or how much DNA an individual leaves behind. A model for determining this would benefit evidence interpretation if passive transfer scenarios are being considered, as it can affect the probative value of DNA evidence. This study compared the amount of DNA collected with adhesive D-Squame tape disks from the fingers of individual’s washed non-dominant and dominant hands after 30 minutes of …


Robert Rosen And Relational System Theory: An Overview, James Lennox Jun 2022

Robert Rosen And Relational System Theory: An Overview, James Lennox

Dissertations, Theses, and Capstone Projects

Relational system theory is the science of organization and function. It is the study of how systems are organized which is based on their functions and the relations between their functions. The science was originally developed by Nicolas Rashevsky, and further developed by Rashevsky’s student Robert Rosen, and continues to be developed by Rosen’s student A. H. Louie amongst others. Due to its revolutionary character, it is often misunderstood, and to some, controversial. We will mainly be focusing on Rosen’s contributions to this science. The formal and conceptual setting for Rosen’s relational system theory is category theory. Rosen was the …


Prenatal Exposure To A Climate-Related Disaster Results In Changes Of The Placental Transcriptome And Infant Temperament, Jessica Buthmann, Dennis Huang, Patrizia Casaccia, Sarah O'Neill, Yoko Nomura Apr 2022

Prenatal Exposure To A Climate-Related Disaster Results In Changes Of The Placental Transcriptome And Infant Temperament, Jessica Buthmann, Dennis Huang, Patrizia Casaccia, Sarah O'Neill, Yoko Nomura

Advanced Science Research Center

Maternal stress during pregnancy exerts long-term effects on the mental well-being of the offspring. However, the long-term effect of prenatal exposure on the offspring’s mental status is only partially understood. The placenta plays a vital role in connecting the maternal side to the fetus, thereby serving as an important interface between maternal exposure and fetal development. Here, we profiled the placental transcriptome of women who were pregnant during a hurricane (Superstorm Sandy), which struck New York City in 2012. The offspring were followed longitudinally and their temperament was assessed during the first 6–12 months of age. The data identified a …


The Central Dogma: Gene Expression, Ayisha Sookdeo Apr 2022

The Central Dogma: Gene Expression, Ayisha Sookdeo

Open Educational Resources

In this lesson plan, students will learn the basic structure and function of DNA and RNA. They will also learn the process of gene expression. Finally, students will learn about the scientific contributor, Ernest Everest Just, and his contributions to the field of Biology.


A Role For Myosin Ii Clusters And Membrane Energy In Cortex Rupture For Dictyostelium Discoideum, Emmanuel Asante-Asamani, Daniel Grange, Devarshi Rawal, Zully Santiago, John Loustau, Derrick Brazill Apr 2022

A Role For Myosin Ii Clusters And Membrane Energy In Cortex Rupture For Dictyostelium Discoideum, Emmanuel Asante-Asamani, Daniel Grange, Devarshi Rawal, Zully Santiago, John Loustau, Derrick Brazill

Publications and Research

Blebs, pressure driven protrusions of the cell membrane, facilitate the movement of eukaryotic cells such as the soil amoeba Dictyostelium discoideum , white blood cells and cancer cells. Blebs initiate when the cell membrane separates from the underlying cortex. A local rupture of the cortex, has been suggested as a mechanism by which blebs are initiated. However, much clarity is still needed about how cells inherently regulate rupture of the cor- tex in locations where blebs are expected to form. In this work, we examine the role of mem- brane energy and the motor protein myosin II (myosin) in facilitating …


Understanding Species Interactions And Their Impacts In Restored Communities, Jennifer Zhu Feb 2022

Understanding Species Interactions And Their Impacts In Restored Communities, Jennifer Zhu

Dissertations, Theses, and Capstone Projects

Species interactions may mediate the ability of organisms to survive in a community and provide valued services but are rarely fully considered in restoration planning. To address this, I considered how service provisioning will change as restored marsh communities mature and the value of incorporating antipredator training into captive-rearing programs.

For chapter 1, I explored how a facultative mutualism between Atlantic ribbed mussels Geukensia demissa and cordgrass Spartina alterniflora may enhance marsh growth and nitrogen cycling in a eutrophic setting. I created experimental plots in Jamaica Bay, NY, that contained live mussels, mussel shells, or no mussels (control) and measured …


Novel Strategies For Glutamate Clearance In The Glia-Deprived Synaptic Hub Of C. Elegans, Joyce Chan Feb 2022

Novel Strategies For Glutamate Clearance In The Glia-Deprived Synaptic Hub Of C. Elegans, Joyce Chan

Dissertations, Theses, and Capstone Projects

As the major excitatory neurotransmitter in the mammalian brain, Glutamate (Glu) is critical for normal neuronal physiology. Disruption in Glu clearance results in hyper-stimulation of glutamatergic circuits, potentially leading to excitotoxic neurodegeneration. The canonical model of brain connectivity describes glutamatergic synapses as well insulated and enveloped by glia. These glia express Glu Transporters (GluTs) which work to clear Glu following synaptic activity. However, critical areas of the brain such as the mammalian hippocampus display poor synaptic isolation, which may result in Glu spillover between adjacent synapses and subsequent loss of circuit specificity. How accurate signal transmission is achieved in these …


Molecular Mechanisms Of Microrna-1205 In Aggressive Prostate Cancer, Michelle K. Naidoo Feb 2022

Molecular Mechanisms Of Microrna-1205 In Aggressive Prostate Cancer, Michelle K. Naidoo

Dissertations, Theses, and Capstone Projects

Prostate cancer (PCa) is one of the most commonly diagnosed cancers among men in the United States. High mortality rates of PCa are associated with metastatic castration-resistant prostate cancer (mCRPC) due to the maintenance of androgen receptor (AR) signaling despite androgen deprivation therapies (ADTs). Resistance to second generation ADTs leads to the progression of AR-independent treatment related-neuroendocrine PCa (t-NEPC), which is observed in nearly 1 in 5 men with mCRPC and is associated with very poor outcomes. The 8q24 chromosomal locus is a region of very high PCa susceptibility that carries genetic variants associated with PCa aggressiveness. Located at this …


Maternal Choline Supplementation And High-Fat Feeding Interact To Influence Dna Methylation In Offspring In A Time-Specific Manner, Hunter W. Korsmo, Bhoomi Dave, Steven E. Trasino, Anjana Saxena, Jia Liu, Jorge Matias Caviglia, Kaydine Edwards, Moshe Dembitzer, Shameera Sheeraz, Sarah Khaldi, Xinyin Jiang Jan 2022

Maternal Choline Supplementation And High-Fat Feeding Interact To Influence Dna Methylation In Offspring In A Time-Specific Manner, Hunter W. Korsmo, Bhoomi Dave, Steven E. Trasino, Anjana Saxena, Jia Liu, Jorge Matias Caviglia, Kaydine Edwards, Moshe Dembitzer, Shameera Sheeraz, Sarah Khaldi, Xinyin Jiang

Advanced Science Research Center

Maternal methyl donor supplementation during pregnancy has demonstrated lasting influence on offspring DNA methylation. However, it is unknown whether an adverse postnatal environment, such as high-fat (HF) feeding, overrides the influence of prenatal methyl donor supplementation on offspring epigenome. In this study, we examined whether maternal supplementation of choline (CS), a methyl donor, interacts with prenatal and postnatal HF feeding to alter global and site-specific DNA methylation in offspring. We fed wild-type C57BL/6J mouse dams a HF diet with or without CS throughout gestation. After weaning, the offspring were exposed to HF feeding for 6 weeks resembling a continued obesogenic …


Introduction To Epigenetics, Yevgeniy Grigoryev Jan 2022

Introduction To Epigenetics, Yevgeniy Grigoryev

Open Educational Resources

Syllabus for Bio481 Introduction to Epigenetics


A Study Protocol To Prepare An Rbd Protein For Vaccine Against Covid-19, Z.M.G. Sarwar Jahangir, Arleta Helena Marnik Jan 2022

A Study Protocol To Prepare An Rbd Protein For Vaccine Against Covid-19, Z.M.G. Sarwar Jahangir, Arleta Helena Marnik

Publications and Research

Background: SARS-CoV-2 pandemic is a global threat to humans and the world’s economy. Effective and safe vaccines against this virus are essential to control and eradicate the pandemic. The currently applied vaccines carry SARS-CoV-2 spike-protein mRNA/cDNA. These vaccines go through several cellular processes in the recipients for producing antigens. On the contrary, the SARS-CoV-2 RBD (receptor binding domain)-protein is an antigen. It will directly stimulate antibody production against SARS-CoV-2. Hence, we propose to produce SARS-CoV-2 RBD-protein as a fast acting, effective and safe vaccine.


Methods: We propose to reconstruct a plasmid carrying three types of DNA sequences: RBD cDNA, FP …


The Role Of Slu7 In Spliceosome Function In Saccharomyces Cerevisiae, Sovira A. Chaudhry Jan 2022

The Role Of Slu7 In Spliceosome Function In Saccharomyces Cerevisiae, Sovira A. Chaudhry

Theses and Dissertations

The removal of introns from pre-messenger RNA via splicing in the nucleus is an essential step in gene expression. In recent decades, significant effort has been made to understand the chemical mechanisms of splicing reactions and the composition of the spliceosome that catalyzes them. Yet very little is known about the exact function of many splicing factors and small proteins within the spliceosome. Slu7, a pre-mRNA splicing factor, is essential during the second catalytic step of splicing because it interacts with several proteins and stabilizes the active site conformation. It has been found that Slu7 is involved in 3' splice …


Using Image To Assist Students In Construct Searching Concepts And Framing Research Questions, Junli Diao Jan 2022

Using Image To Assist Students In Construct Searching Concepts And Framing Research Questions, Junli Diao

Open Educational Resources

No abstract provided.


Assembly Mechanism Of Early Hsp90-Cdc37-Kinase Complexes, Dimitra Keramisanou, M.V. Vasantha Kumar, Nicole Boose, Rinat R. Abzalimov, Ioannis Gelis Jan 2022

Assembly Mechanism Of Early Hsp90-Cdc37-Kinase Complexes, Dimitra Keramisanou, M.V. Vasantha Kumar, Nicole Boose, Rinat R. Abzalimov, Ioannis Gelis

Advanced Science Research Center

Molecular chaperones have an essential role for the maintenance of a balanced protein homeostasis. Here, we investigate how protein kinases are recruited and loaded to the Hsp90-Cdc37 complex, the first step during Hsp90-mediated chaperoning that leads to enhanced client kinase stability and activation. We show that conformational dynamics of all partners is a critical feature of the underlying loading mechanism. The kinome co-chaperone Cdc37 exists primarily in a dynamic extended conformation but samples a low-populated, well-defined compact structure. Exchange between these two states is maintained in an assembled Hsp90-Cdc37 complex and is necessary for substrate loading. Breathing motions at the …


Importin-Mediated Pathological Tau Nuclear Translocation Causes Disruption Of The Nuclear Lamina, Tdp-43 Mislocalization And Cell Death, Robert F. Candia, Leah S. Cohen, Viktoriya Morozova, Christopher Corbo, Alejandra D. Alonso Jan 2022

Importin-Mediated Pathological Tau Nuclear Translocation Causes Disruption Of The Nuclear Lamina, Tdp-43 Mislocalization And Cell Death, Robert F. Candia, Leah S. Cohen, Viktoriya Morozova, Christopher Corbo, Alejandra D. Alonso

Publications and Research

Tau is a cytosolic protein that has also been observed in the nucleus, where it has multiple proposed functions that are regulated by phosphorylation. However, the mechanism underlying the nuclear import of tau is unclear, as is the contribution of nuclear tau to the pathology of tauopathies. We have previously generated a pathological form of tau, PH-tau (pseudophosphorylation mutants S199E, T212E, T231E, and S262E) that mimics AD pathological behavior in cells, Drosophila, and a mouse model. Here, we demonstrated that PH-tau translocates into the nucleus of transiently transfected HEK-293 cells, but wildtype tau does not. We identified a putative …


The Role Of Rna Helicase Rhau In Immunoglobulin Class Switch Recombination, Sabine Jean Guillaume Jan 2022

The Role Of Rna Helicase Rhau In Immunoglobulin Class Switch Recombination, Sabine Jean Guillaume

Dissertations and Theses

B cells alter the expression of immunoglobulin isotypes through a process known as class switch recombination (CSR). In these cells, activation induced cytidine deaminase (AID) binds Gquadruplex (G4) switch transcripts, which serve as guide RNAs to target AID to the immunoglobulin heavy chain switch (S) regions in the DNA for CSR. Sequence alignment revealed homology between the AID G4 binding domain and the RNA helicase associated with AU-rich element (RHAU) specific motif (RSM), which allows RHAU binding to G4 RNAs and subsequent unwinding of G4 RNA into single-stranded transcripts. We hypothesize that RHAU functions in CSR by binding G4 S …


Exosome- And Microrna-Based Therapeutic Approach For Tendinopathy, Angela Wang Ilaltdinov Jan 2022

Exosome- And Microrna-Based Therapeutic Approach For Tendinopathy, Angela Wang Ilaltdinov

Dissertations and Theses

Tendinopathy, characterized by degeneration and chronic inflammation, is a significant clinical burden. Current treatments focus on symptom management but do not sufficiently address its underlying pathology; however, stem cell-based approaches aimed at repairing diseased tissues may overcome this limitation. Therapeutic effects of stem cells may be due in part to paracrine actions, including some mediated by exosomes – extracellular vesicles secreted by cells that play a role in cell communication. MicroRNA (miRNA), small non-coding RNA carried by exosomes, are likely responsible for many exosome effects. Exosomes and miRNA therapies show promise in treating diseases such as cancer and arthritis, but …


Evaluating A Test For Shedding Propensity Using Tape Lifts From Different Skin Locations, Xiao M. Chen Dec 2021

Evaluating A Test For Shedding Propensity Using Tape Lifts From Different Skin Locations, Xiao M. Chen

Student Theses

The shedding propensity of a person can assist data interpretation in casework when assessing the possibility of passive transfer for DNA analysis. Past studies on shedding propensity evaluated palmar skin (washed and unwashed) deposits. This study compared different skin locations with respect to shedding propensity, and explored the potential of tape-lifts as a skin surface collection method. Eight different skin types and samples were collected with adhesive tape disks from 28 participants over three non-consecutive days; the washed and unwashed fingers from both hands, toe, and arm, neck below ear, and nape. Samples were extracted, quantified, amplified, genotyped, and evaluated …


Exploration Of Dark Chemical Genomics Space Via Portal Learning: Applied To Targeting The Undruggable Genome And Covid-19 Anti-Infective Polypharmacology, Tian Cai, Li Xie, Muge Chen, Yang Liu, Di He, Shuo Zhang, Cameron Mura, Philip Boume, Lei Xie Dec 2021

Exploration Of Dark Chemical Genomics Space Via Portal Learning: Applied To Targeting The Undruggable Genome And Covid-19 Anti-Infective Polypharmacology, Tian Cai, Li Xie, Muge Chen, Yang Liu, Di He, Shuo Zhang, Cameron Mura, Philip Boume, Lei Xie

Publications and Research

Advances in biomedicine are largely fueled by exploring uncharted territories of human biology. Machine learning can both enable and accelerate discovery, but faces a fundamental hurdle when applied to unseen data with distributions that differ from previously observed ones—a common dilemma in scientific inquiry. We have developed a new deep learning framework, called Portal Learning , to explore dark chemical and biological space. Three key, novel components of our approach include: (i) end-to-end, step-wise transfer learning, in recognition of biology’s sequence-structure-function paradigm, (ii) out-of-cluster meta-learning, and (iii) stress model selection. Portal Learning provides a practical solution to the out-of-distribution (OOD) …