Medicinal-Pharmaceutical Chemistry Commons^™

Norman H. Cromwell, Unl Chemistry; Nu System Dean; Eppley Cancer Center Director, Norman H. Cromwell, Pete Boughn, Mark A. Griep

UNL ORCA Interview Series

This 1980 interview of Normal Cromwell was done by Pete Boughn at the University of Nebraska Medical Center in Omaha. He asked about Cromwell’s history but mostly about his time as director of the Eppley Cancer Center. The interview is reproduced with permission from the UNMC McGoogan Library.

Cromwell was born in 1913 in Terre Haute, Indiana. In 1935, he earned a bachelor’s degree in chemical engineering from the Rose-Hulman Institute of Technology in his hometown. In 1939, three things happened: he earned a doctorate in organic chemistry from the University of Minnesota, he got married, and he was hired …

Synthesis And Study Of Stable Organic Radicals For Mri Contrast Agents And New Materials, Sabina Dhakal

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The first part of this dissertation focuses on the design, synthesis, and characterization of a thermally robust S =1/2 phototetrazolinyl monoradical and the development of synthetic methodologies for a high-spin (S = 1) phototetrazolinyl diradical. Electrochemical studies of the phototetrazolium cation (precursor to the monoradical) revealed a remarkably narrow electrochemical band gap (Ecell ≈ 0.82 V), suggesting promising electrical conductivity. Thermal analysis of the monoradical demonstrated excellent stability, with the onset of decomposition at 232 °C. Building on the excellent thermal stability and promising properties for electrical conductivity of the monoradical, we developed two condensation-based synthetic routes that provide viable …

Optimizing Transcription Efficiency Through Mutations In The T7 Rna Polymerase, Claire N. Novak

Honors Program: Senior Projects (Public)

The production of RNA is vital for many commercial and research purposes, with one of the more notable reasons being vaccine production. The RNA polymerase, derived from T7 bacteriophage, is commonly used for RNA production due to its ability to produce full-length RNA transcripts. However, researchers have faced limitations in optimizing this polymerase. For example, the polymerase generates heterogeneous RNA products that require additional purification steps during RNA production. Here, we selected three amino acid point substitutions based on a recent publication from Moderna that showed increased RNA purity compared to the wild type T7 RNA polymerase sequence. We created …

Brain Endothelial Permeability, Transport, And Flow Assessed Over 10 Orders Of Magnitude Using The In Situ Brain Perfusion Technique, Quentin R. Smith, Haritha Mandula, Jagan Mohan R. Parepally, Jun Oki, Fancy Thomas, Helen R. Thorsheim, Abraham J. Al‑Ahmad, Thomas J. Abbruscato, Per Ask, David S. Hage, Peter J. Robinson

David Hage Publications

Background Cerebral blood flow normally places a limit on the magnitude of brain vascular permeability (P) that can be measured in vivo. At normal cerebral blood flow, this limit falls at the lower end of lipophilicity for most FDAapproved CNS drugs. In this study, we report on two methods that can be used to overcome this limitation and measure brain vascular permeability values that are up to ~1000 times higher using the in situ brain perfusion technique.

Methods Rat brain was perfused with physiological saline at increased flow rate and in the presence of various concentrations of plasma protein, serum …

Editorial: Leveraging Multi-Omics Approaches To Understand And Manage Gastrointestinal And Hepatic Diseases, Isis Trujillo-Gonzalez, Paul G. Thomes, Isin Tuna Sakallioglu, Kusum K. Kharbanda

Department of Chemistry: Faculty Publications

The Research Topic “Leveraging multi-omics approaches to understand and manage gastrointestinal and hepatic diseases” proposed by the Frontiers in Pharmacology has attracted a total of four articles on preclinical studies that were covered in three original research manuscripts and one review article. Two research articles were on metabolic dysfunction-associated steatotic liver disease (MASLD), previously named non-alcoholic fatty liver disease (NAFLD), which is now recognized as a predominant cause of chronic liver disease worldwide, affecting over 30% of the adult population (Teng et al., 2023; Miao et al., 2024). Current pharmacological treatments for MASLD are limited and, until a recent FDA-approved …

Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Applications For Metabolomics, Darcy Cochran, Robert Powers

Robert Powers Publications

Metabolomics is an interdisciplinary field that aims to study all metabolites < 1500 Da that are ubiquitously found within all organisms. Metabolomics is experiencing exponential growth and commonly relies on high-resolution mass spectrometry (HRMS). Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is a form of HRMS that is particularly well suited for metabolomics research due to its exceptionally high resolution (10⁵–10⁶) and sensitivity with a mass accuracy in parts per billion (ppb). In this regard, FT-ICR-MS can provide valuable insights into the metabolomics analysis of complex biological systems due to unique capabilities such as the easy separation of isobaric and isomeric species, isotopic fine structure analysis, spatial resolution of metabolites in cells and tissues, and a high confidence (error) in metabolite identification. Alternatively, the large and complex data sets, long acquisition times, high cost, and limited access mainly through national mass spectrometry facilities may impede the …

Production Of The Siderophore Lysochelin In Rich Media Through Maltose-Promoted High-Density Growth Of Lysobacter Sp. 3655, Fang Zhang, Jia Liu, Lin Jiang, Yongbiao Zheng, Lingjun Yu, Liangcheng Du

Department of Chemistry: Faculty Publications

Siderophores are produced by bacteria in iron-restricted conditions. However, we found maltose could induce the biosynthesis of the siderophore lysochelin in Lysobacter sp. 3655 in rich media that are not compatible with siderophore production. Maltose markedly promoted cell growth, with over 300% increase in cell density (OD₆₀₀) when LB medium was added with maltose (LBM). While lysochelin was not detectable when OD₆₀₀ in LBM was below 5.0, the siderophore was clearly produced when OD₆₀₀ reached 7.5 and dramatically increased when OD₆₀₀ was 15.0. Coincidently, the transcription of lysochelin biosynthesis genes was remarkably enhanced following the …

Potential Metabolite Biomarkers Of Multiple Sclerosis From Multiple Biofluids, Fatema Bhinderwala, Heidi E. Roth, Mary Filipi, Samantha Jack, Robert Powers

Robert Powers Publications

Multiple sclerosis (MS) is a chronic and progressive neurological disorder without a cure, but early intervention can slow disease progression and improve the quality of life for MS patients. Obtaining an accurate diagnosis for MS is an arduous and error-prone task that requires a combination of a detailed medical history, a comprehensive neurological exam, clinical tests such as magnetic resonance imaging, and the exclusion of other possible diseases. A simple and definitive biofluid test for MS does not exist but is highly desirable. To address this need, we have employed NMR-based metabolomics to identify potentially unique metabolite biomarkers of MS …

Leveraging The Hmbc To Facilitate Metabolite Identification, Fatema Bhinderwala, Thao Vu, Thomas G. Smith, Julian Kosacki, Darrell D. Marshall, Yuhang Xu, Martha D. Morton, Robert Powers

Department of Chemistry: Faculty Publications

The accuracy and ease of metabolite assignments from a complex mixture are expected to be facilitated by employing a multi-spectral approach. The 2D ¹H-¹³C HSQC and 2D ¹H-¹H-TOCSY are the experiments commonly used for metabolite assignments. The 2D ¹H-¹³C HSQC-TOCSY and 2D ¹H-¹³C HMBC are routinely used by natural products chemists but have seen minimal usage in metabolomics despite the unique information, the nearly complete ¹H-¹H and ¹H-¹³C and spin systems provided by these experiments that may improve the accuracy and reliability …

Cancer-Associated Fibroblast-Derived Acetate Promotes Pancreatic Cancer Development By Altering Polyamine Metabolism Via The Acss2–Sp1–Sat1 Axis, Divya Murthy, Kuldeep S. Attri, Surendra K. Shukla, Ravi Thakur, Nina V. Chaika, Chunbo He, Dezhen Wang, Kanupriya Jha, Aneesha Dasgupta, Ryan J. King, Scott E. Mulder, Joshua Souchek, Teklab Gebregiworgis, Vikant Rai, Rohit Patel, Tuo Hu, Sandeep Rana, Sai Sundeep Kollala, Camila Pacheco, Paul M. Grandgenett, Fang Yu, Vikas Kumar, Audrey J. Lazenby, Adrian R. Black, Susanna Ulhannan, Ajay Jain, Barish H. Edil, David L. Klinkebiel, Robert Powers, Amarnath Natarajan, Michael A. Hollingsworth, Kamiya Mehla2,, Quan Ly, Sarika Chaudhary, Rosa F. Hwang, Kathryn E. Wellen, Pankaj K. Singh

Robert Powers Publications

The ability of tumour cells to thrive in harsh microenvironments depends on the utilization of nutrients available in the milieu. Here we show that pancreatic cancer-associated fibroblasts (CAFs) regulate tumour cell metabolism through the secretion of acetate, which can be blocked by silencing ATP citrate lyase (ACLY) in CAFs. We further show that acetyl-CoA synthetase short-chain family member 2 (ACSS2) channels the exogenous acetate to regulate the dynamic cancer epigenome and transcriptome, thereby facilitating cancer cell survival in an acidic microenvironment. Comparative H3K27ac ChIP–seq and RNA–seq analyses revealed alterations in polyamine homeostasis through regulation of SAT1 gene expression and enrichment …

Tunable Magnetic Coupling In Graphene Nanoribbon Quantum Dots, Peter H. Jacobse, Mamun Sarker, Anshul Saxena, Brookhaven National Laboratory, Ziyi Wang, Emma Berger, Narayana R. Aluru, Alexander Sinitskii, Michael F. Crommie

Department of Chemistry: Faculty Publications

Carbon-based quantum dots (QDs) enable flexible manipulation of electronic behavior at the nanoscale, but controlling their magnetic properties requires atomically precise structural control. While magnetism is observed in organic molecules and graphene nanoribbons (GNRs), GNR precursors enabling bottom-up fabrication of QDs with various spin ground states have not yet been reported. Here the development of a new GNR precursor that results in magnetic QD structures embedded in semiconducting GNRs is reported. Inserting one such molecule into the GNR backbone and graphitizing it results in a QD region hosting one unpaired electron. QDs composed of two precursor molecules exhibit nonmagnetic, antiferromagnetic, …

Postsynthetic Modification Of The Nonanuclear Node In A Zirconium Metal−Organic Framework For Photocatalytic Oxidation Of Hydrocarbons, Rebecca Shu Hui Khoo, Christian Fiankor, Sizhuo Yang, Wenhui Hu, Chongqing Yang, Jingzhi Lu, Martha D. Morton, Xu Zhang, Yi Liu, Jier Huang, Jian Zhang

Department of Chemistry: Faculty Publications

Heterogeneous catalysis plays an indispensable role in chemical production and energy conversion. Incorporation of transition metals into metal oxides and zeolites is a common strategy to fine-tune the activity and selectivity of the resulting solid catalysts, as either the active center or promotor. Studying the underlying mechanism is however challenging. Decorating the metal-oxo clusters with transition metals in metal−organic frameworks (MOFs) via postsynthetic modification offers a rational approach to construct well-defined structural models for better understanding of the reaction mechanism. Therefore, it is important to expand the materials scope beyond the currently widely studied zirconium MOFs consisting of Zr_{6 …}

Machine Learning‑Assisted Low‑Dimensional Electrocatalysts Design For Hydrogen Evolution Reaction, Jin Li, Naiteng Wu, Jian Zhang, Hong‑Hui Wu, Kunming Pan, Yingxue Wang, Guilong Liu, Xianming Liu, Zhenpeng Yao, Qiaobao Zhang

Department of Chemistry: Faculty Publications

Efficient electrocatalysts are crucial for hydrogen generation from electrolyzing water. Nevertheless, the conventional "trial and error" method for producing advanced electrocatalysts is not only cost-ineffective but also time-consuming and labor-intensive. Fortunately, the advancement of machine learning brings new opportunities for electrocatalysts discovery and design. By analyzing experimental and theoretical data, machine learning can effectively predict their hydrogen evolution reaction (HER) performance. This review summarizes recent developments in machine learning for low-dimensional electrocatalysts, including zero-dimension nanoparticles and nanoclusters, one-dimensional nanotubes and nanowires, two-dimensional nanosheets, as well as other electrocatalysts. In particular, the effects of descriptors and algorithms on screening low-dimensional electrocatalysts …

Strengthening Brain Research In Africa, Abdullahi Tunde Aborode, Nike Jesutofunmi Idowu, Samuel Tundealao, Joseph Jaiyeola, Ogunware Adedayo Emmanuel

Department of Chemistry: Faculty Publications

This paper explores the emerging field of neuroscience in Africa, considering the unique genetic diversity, sociocultural determinants, and health inequalities in the continent. It presents numerous brain research initiatives, such as ABDRN, AMARI, APCDR, and H3Africa, aimed at understanding genetic and environmental factors influencing brain disorders in Africa. Despite numerous challenges like the brain drain phenomenon, inadequate infrastructure, and scarce research expertise, significant progress has been achieved. The paper proposes solutions, including international collaboration, capacity-building efforts, and policies to promote neuroscience research, to enhance the understanding of brain function and address brain-related health issues within the African context.

Introducing High School Biology Students To Biochemistry With A Short, Content-Oriented Module, Archer Harrold, Allison Cruikshank, Bryan Penas, Rebecca Roston

Department of Chemistry: Faculty Publications

Many STEM disciplines are underrepresented to High School students. This is problematic as many students' decisions for college are shaped by their experiences and achievements in high school. Short content-oriented modules have been shown to encourage science identity and otherwise benefit the students' learning. Following the ASBMB's outreach protocol, we developed a short content-oriented module aimed at a high school biology classroom. Students interacted with 3D models of DNA and transcription factors while exploring structure–function relationships and introductory biochemistry topics. The high school teacher was impressed with the students' response to the module, specifically the ease with which students learned, …

Changes In An Enzyme Ensemble During Catalysis Observed By High Resolution Xfel Crystallography, Nathan J. Smith, Medhanjali Dasgupta, David C. Wych, Cole Dolamore, Raymond G. Sierra, Stella Lisova, Darya Marchany-Rivera, Aina E. Cohen, Sébastien Boutet, Mark S. Hunter, Christopher Kupitz, Frédéric Poitevin, Frank R. Moss Iii, Aaron S. Brewster, Nicholas K. Sauter, Iris D. Young, Alexander M. Wolff, Virendra K. Tiwari, Nivesh Kumar, David B. Berkowitz, Ryan G. Hadt, Michael C. Thompson, Alec H. Follmer, Mark A. Wilson

Department of Chemistry: Faculty Publications

Enzymes populate ensembles of structures with intrinsically different catalytic proficiencies that are difficult to experimentally characterize. We use time-resolved mix-and-inject serial crystallography (MISC) at an X-ray free electron laser (XFEL) to observe catalysis in a designed mutant (G150T) isocyanide hydratase (ICH) enzyme that enhances sampling of important minor conformations. The active site exists in a mixture of conformations and formation of the thioimidate catalytic intermediate selects for catalytically competent substates. A prior proposal for active site cysteine charge-coupled conformational changes in ICH is validated by determining structures of the enzyme over a range of pH values. A combination of large …

On The Boundary Of The Cosmos, Daniel Linford

Department of Chemistry: Faculty Publications

Intuitively, the totality of physical reality – the Cosmos – has a beginning only if (i) all parts of the Cosmos agree on the direction of time (the Direction Condition) and (ii) there is a boundary to the past of all non-initial spacetime points such that there are no spacetime points to the past of the boundary (the Boundary Condition). Following a distinction previously introduced by J. Brian Pitts, the Boundary Condition can be conceived of in two distinct ways: either topologically, i.e., in terms of a closed boundary, or metrically, i.e., in terms of the Cosmos having a finite …

Differential Membrane Binding Of Α/Β-Peptide Foldamers: Implications For Cellular Delivery And Mitochondrial Targeting, Tzong-Hsien Lee, James W. Checco, Tess Malcolm, Chelcie H. Eller, Ronald T. Raines, Samuel H. Gellman, Erinna F. Lee, W. Douglas Fairlie, Marie-Isabel Aguilar

Department of Chemistry: Faculty Publications

The intrinsic pathway of apoptosis is regulated by the Bcl-2 family of proteins. Inhibition of the anti-apoptotic members represents a strategy to induce apoptotic cell death in cancer cells. We have measured the membrane binding properties of a series of peptides, including modified α/β-peptides, designed to exhibit enhanced membrane permeability to allow cell entry and improved access for engagement of Bcl-2 family members. The peptide cargo is based on the pro-apoptotic protein Bim, which interacts with all anti-apoptotic proteins to initiate apoptosis. The α/β-peptides contained cyclic β-amino acid residues designed to increase their stability and membrane-permeability. Dual polarisation interferometry was …

Temperature-Pressure Phase Diagram Of Confined Monolayer Water/Ice At First-Principles Accuracy With A Machine-Learning Force Field, Bo Lin, Jian Jiang, Xiao Cheng Zeng, Lei Li

Department of Chemistry: Faculty Publications

Understanding the phase behaviour of nanoconfined water films is of fundamental importance in broad fields of science and engineering. However, the phase behaviour of the thinnest water film – monolayer water – is still incompletely known. Here, we developed a machine-learning force field (MLFF) at first-principles accuracy to determine the phase diagram of monolayer water/ice in nanoconfinement with hydrophobic walls. We observed the spontaneous formation of two previously unreported high-density ices, namely, zigzag quasi-bilayer ice (ZZ-qBI) and branched-zigzag quasi-bilayer ice (bZZ-qBI). Unlike conventional bilayer ices, few inter-layer hydrogen bonds were observed in both quasi-bilayer ices. Notably, the bZZ-qBI entails a …

Long-Term Degradation Mechanisms In Application-Implemented Radical Thin Films, Ewa Malgorzata Nowik-Boltyk, Tobias Junghoefer, Mathias Glaser, Erika Giangrisostomi, Ruslan Ovsyannikov, Shuyang Zhang, Chan Shu, Andrzej Rajca, Arrigo Calzolari, M. Benedetta Casu

Department of Chemistry: Faculty Publications

Blatter radical derivatives are very attractive due to their potential applications, ranging from batteries to quantum technologies. In this work, we focus on the latest insights regarding the fundamental mechanisms of radical thin film (long-term) degradation, by comparing two Blatter radical derivatives. We find that the interaction with different contaminants (such as atomic H, Ar, N, and O and molecular H₂, N₂, O₂, H₂O, and NH₂) affects the chemical and magnetic properties of the thin films upon air exposure. Also, the radical-specific site, where the contaminant interaction takes place, plays …

Stepwise Assembly Of Quinary Multivariate Metal−Organic Frameworks Via Diversified Linker Exchange And Installation, Yuchen Hu, Xin Zhang, Rebecca Shu Hui Khoo, Christian Fiankor, Xu Zhang, Jian Zhang

Department of Chemistry: Faculty Publications

Multivariate MOFs (MTV-MOFs) constructed from multiple components with atomistic precision hold the promise for many fascinating developments in both fundamental sciences and applications. Sequential linker installation can be an effective method to introduce different functional linkers into an MOF that contains coordinatively unsaturated metal sites. However, in many cases, these linkers must be installed according to a specific sequence and the complete synthetic flexibility and freedom is yet to be realized. Here, we rationally decreased the size of the primary ligand used in NPF-300, a Zr-MOF with scu topology (NPF = Nebraska Porous Framework), and synthesized its isostructure, NPF-320. NPF-320 …

Synthesis And Study Of High-Spin Stable Organic Radicals For Electrical Conductors And Mannosamine Nitroxide For Mri Contrast Agents, Shuyang Zhang

Department of Chemistry: Dissertations, Theses, and Student Research

In the first project, we describe the synthesis of an ambient stable high spin organic diradical 4 based on the Blatter moiety. The high-spin (S = 1) organic diradical 4, which consists of two Blatter radical moieties in a conjugated structure, exhibits a nearly exclusive population (88%) on triplet ground state at room temperature as a consequence of a large single-triplet energy gap (ΔEST = 0.5 kcal/mol). The target diradical molecule is synthesized over five steps with structural confirmation by single-crystal X-ray diffraction. The thermogravimetric analysis (TGA) shows the onset of decomposition at ~264 oC, indicating the diradical molecule has …

Ultra-Fast Bioorthogonal Spin-Labeling And Distance Measurements In Mammalian Cells Using Small, Genetically Encoded Tetrazine Amino Acids, Subhashis Jana, Eric G. B. Evans, Hyo Sang Jang, Shuyang Zhang, Hui Zhang, Andrzej Rajca, Sharona E. Gordon, William N. Zagotta, Stefan Stoll, Ryan A. Mehl

Department of Chemistry: Faculty Publications

Studying protein structures and dynamics directly in the cellular environments in which they function is essential to fully understand the molecular mechanisms underlying cellular processes. Site-directed spin-labeling (SDSL)—in combination with double electron–electron resonance (DEER) spectroscopy—has emerged as a powerful technique for determining both the structural states and the conformational equilibria of biomacromolecules. In-cell DEER spectroscopy on proteins in mammalian cells has thus far not been possible due to the notable challenges of spin-labeling in live cells. In-cell SDSL requires exquisite biorthogonality, high labeling reaction rates and low background signal from unreacted residual spin label. While the bioorthogonal reaction must be …

Electronic Transport Properties Of Spin-Crossover Polymer Plus Polyaniline Composites With Fe3O4 Nanoparticles, Esha Mishra, Waikiat Chin, Kayleigh A. Mcelveen, Thilini K. Ekanayaka, M. Zaid Zaz, Gauthami Viswan, Ruthi Zielinski, Alpha T. N'Diaye, David Shapiro, Rebecca Lai, Robert Streubel, Peter A. Dowben

Department of Chemistry: Faculty Publications

Adding Fe₃O₄ nanoparticles to composites of [Fe(Htrz)₂(trz)](BF₄) spin-crossover polymer and polyaniline (PANI) drives a phase separation of both and restores the molecular structure and cooperative effects of the spin-crossover polymer without compromising the increased conductivity gained through the addition of PANI. We observe an increased on-off ratio for the DC conductivity owing to an enlarged off state resistivity and a 20 times larger AC conductivity of the on state compared with DC values. The Fe₃O₄ nanoparticles, primarily confined to the [Fe(Htrz)₂(trz)](BF₄) phase, are ferromagnetically coupled to …

Identification And Biosynthetic Study Of The Siderophore Lysochelin In The Biocontrol Agent Lysobacter Enzymogenes, Amanda Lynn Miller, Shanren Li, Catherine D. Eichhorn, Yongbiao Zheng, Liangcheng Du

Liangcheng Du Publications

Lysobacter is a genus of bacteria emerging as new biocontrol agents in agriculture. Although iron acquisition is essential for the bacteria, no siderophore has been identified from any Lysobacter. Here, we report the identification of the first siderophore, N1,N8-bis(2,3-dihydroxybenzoyl)spermidine (lysochelin), and its biosynthetic gene cluster from Lysobacter enzymogenes. Intriguingly, the deletion of the spermidine biosynthetic gene encoding arginine decarboxylase or SAM decarboxylase eliminated lysochelin and the antifungals, HSAF and its analogues, which are key to the disease control activity and to the survival of Lysobacter under oxidative stresses caused by excess iron. The production of …

Progress In 7sk Ribonucleoprotein Structural Biology, Momodou B. Camara, Amr M. Sobeh, Catherine D. Eichhorn

Department of Chemistry: Faculty Publications

The 7SK ribonucleoprotein (RNP) is a dynamic and multifunctional regulator of RNA Polymerase II (RNAPII) transcription in metazoa. Comprised of the noncoding 7SK RNA, core proteins, and numerous accessory proteins, the most wellknown 7SK RNP function is the sequestration and inactivation of the positive transcription elongation factor b (P-TEFb). More recently, 7SK RNP has been shown to regulate RNAPII transcription through P-TEFb-independent pathways. Due to its fundamental role in cellular function, dysregulation has been linked with human diseases including cancers, heart disease, developmental disorders, and viral infection. Significant advances in 7SK RNP structural biology have improved our understanding of 7SK …

The Reversible Low-Temperature Instability Of Human Dj-1 Oxidative States, Tessa Andrews, Javier Seravallic, Robert Powers

Robert Powers Publications

DJ-1 is a homodimeric protein that is centrally involved in various human diseases including Parkinson disease (PD). DJ-1 protects against oxidative damage and mitochondrial dysfunction through a homeostatic control of reactive oxygen species (ROS). DJ-1 pathology results from a loss of function, where ROS readily oxidizes a highly conserved and functionally essential cysteine (C106). The over-oxidation of DJ-1 C106 leads to a dynamically destabilized and biologically inactivated protein. An analysis of the structural stability of DJ-1 as a function of oxidative state and temperature may provide further insights into the role the protein plays in PD progression. NMR spectroscopy, circular …

Histidine Enhances The Anticancer Effect Of Gemcitabine Against Pancreatic Cancer Via Disruption Of Amino Acid Homeostasis And Oxidant—Antioxidant Balance, Narendra Kumar, Satyanarayana Rachagani, Gopalakrishnan Natarajan, Alexandra Crook, Thiyagarajan Gopal, Vinothkumar Rajamanickam, Jyoti B. Kaushal, Sirpu N. Nagabhishek, Robert Powers, Surinder K. Batra, Viswanathan Saraswathi

Robert Powers Publications

Simple Summary: Amino acid metabolism is aberrantly altered in pancreatic cancer (PC). Evidence suggests that circulating histidine (His) levels are low in PC. However, the role of His in modulating the progression of PC remains unknown. We determined the role of His in altering the therapeutic effectiveness of gemcitabine (Gem) against PC. We provide evidence that the expression of histidine ammonia lyase (HAL), an enzyme involved in His catabolism, is greatly increased in mouse and human pancreatic tumors. We show that combining His with Gem led to enhanced cytotoxic effects against aggressive PC cell lines. Our metabolomics analysis revealed that …

Multiplatform Untargeted Metabolomics, Micah J. Jeppesen, Robert Powers

Robert Powers Publications

Metabolomics samples like human urine or serum contain upwards of a few thousand metabolites, but individual analytical techniques can only characterize a few hundred metabolites at best. The uncertainty in metabolite identification commonly encountered in untargeted metabolomics adds to this low coverage problem. A multiplatform (multiple analytical techniques) approach can improve upon the number of metabolites reliably detected and correctly assigned. This can be further improved by applying synergistic sample preparation along with the use of combinatorial or sequential non-destructive and destructive techniques. Similarly, peak detection and metabolite identification strategies that employ multiple probabilistic approaches have led to better annotation …

Exploring The Complementarity Of Measures Of Instructional Practices, Lu Shi, Robert M. Erdmann, Anthony Pellegrini, Victoria Johnson, Binh Le, Trina Popple, Zachary Nelson, Molly Undersander Gaston, Marilyne Stains

Department of Chemistry: Faculty Publications

The assessment of instructional quality has been and continues to be a desirable, yet difficult endeavor in higher education. The development of new teaching evaluation frameworks along with instruments to measure various aspects of teaching practices holds promise. The challenge rests in the implementation of these frameworks and measures in authentic settings. Part of this challenge is for instructors, researchers, and administrators to parse through and select a meaningful set of tools from the plethora of existing instruments. In this study, we aim to start clarifying the landscape of measures of instructional practice by exploring the complementarity of two existing …