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Optical And Structural Studies Of Homoepitaxially Grown M-Plane Gan, S. Khromov, B. Monemar, Vitaliy Avrutin, Xing Li, Hadis Morkoç, L. Hultman, G. Pozina

Electrical and Computer Engineering Publications

Cathodoluminescence(CL) and transmission electron microscopy studies of homoepitaxiallygrownm-plane Mg-doped GaN layers are reported. Layers contain basal plane and prismatic stacking faults (SFs) with ∼10⁶cm⁻¹ density. Broad emission peaks commonly ascribed to SFs were found to be insignificant in these samples. A set of quite strong, sharp lines were detected in the same spectral region of 3.36–3.42 eV. The observed peaks are tentatively explained as excitons bound to some impurity defects, which can also be related to SFs. Donor-acceptor pair (DAP) recombination involving Si or O and Mg was ruled out by fitting DAP energies and …

Racial Differences In Symptom Management Approaches Among Persons With Radiographic Knee Osteoarthritis, Shibing Yang, Rachel Jawahar, Timothy Mcalindon, Charles B. Eaton, Kate L. Lapane

Family Medicine and Population Health Publications

Background

The extent to which racial differences exist in use of treatments for osteoarthritis (OA) is debatable. The purpose of this study was to describe the differences between African Americans (AA) and Caucasian Americans (CA) in using treatment approaches to manage symptoms among individuals with radiographic-confirmed knee OA.

Methods

A cross-sectional study was conducted. Using data from the Osteoarthritis Initiative, we identified 508 AA and 2,075 CA with radiographic tibiofemoral OA in at least one knee. Trained interviewers asked questions relating to current OA treatments including seven CAM therapy categories—alternative medical systems, mind-body interventions, manipulation and body-based methods, energy therapies, …

Immunotherapy Of Cancer: Reprogramming Tumor-Immune Crosstalk, Kyle K. Payne, Amir A. Toor, Xiang-Yang Wang, Masoud H. Manjili

Microbiology and Immunology Publications

The advancement of cancer immunotherapy faces barriers which limit its efficacy. These include weak immunogenicity of the tumor, as well as immunosuppressive mechanisms which prevent effective antitumor immune responses. Recent studies suggest that aberrant expression of cancer testis antigens (CTAs) can generate robust antitumor immune responses, which implicates CTAs as potential targets for immunotherapy. However, the heterogeneity of tumor cells in the presence and quantity of CTA expression results in tumor escape from CTA-specific immune responses. Thus, the ability to modulate the tumor cell epigenome to homogenously induce expression of such antigens will likely render the tumor more immunogenic. Additionally, …

Endoplasmic Reticulum Stress And Lipid Metabolism, Huiping Zhou, Kezhong Zhang, Sabina Janciauskiene, Xiaokun Li

Microbiology and Immunology Publications

Endoplasmic reticulum (ER) is an elaborate cellular organelle essential for protein folding, calcium homeostasis, and lipid biosynthesis. Disruption of ER homeostasis imposes stress on the ER and subsequently leads to accumulation of unfolded or misfolded proteins in the ER lumen—a condition termed ER stress. In response to ER stress, a group of intracellular signaling pathways originated from the ER, collectively termed ER stress response, are activated to alter transcriptional and translational programs in the stressed cells. ER stress response has been linked to various human diseases associated with dyslipidemia, such as inflammatory diseases, obesity, diabetes, alcoholic and nonalcoholic liver diseases, …

Identification And Characterization Of A Novel Calcium-Activated Apyrase Fromcryptosporidium Parasites And Its Potential Role In Pathogenesis, Patricio A. Manque, Ute Woehlbier, Ana M. Lara, Fernando Tenjo, João M. Alves, Gregory A. Buck

Microbiology and Immunology Publications

Herein, we report the biochemical and functional characterization of a novel Ca2+-activated nucleoside diphosphatase (apyrase), CApy, of the intracellular gut pathogen Cryptosporidium. The purified recombinant CApy protein displayed activity, substrate specificity and calcium dependency strikingly similar to the previously described human apyrase, SCAN-1 (soluble calcium-activated nucleotidase 1). CApy was found to be expressed in both Cryptosporidium parvum oocysts and sporozoites, and displayed a polar localization in the latter, suggesting a possible co-localization with the apical complex of the parasite. In vitro binding experiments revealed that CApy interacts with the host cell in a dose-dependent fashion, implying the presence of …

Tumor Escape And Progression Under Immune Pressure, Masoud H. Manjili, Nejat Egilmez, Keith L. Knutson, Senthamil R. Selvan, Julie R. Ostberg

Microbiology and Immunology Publications

Although cancers develop and progress in immunocompetent hosts, immunological therapies for cancer have been proposed as alternative or complementary approaches to more standard therapy. It was initially thought that tumors were silent to the immune system, and that breaking immunological tolerance could result in immune-mediated tumor rejection. However, we have learned that cancer patients have preexisting immune responses against their tumor antigens which, nevertheless, fail to protect them, in part because of increased activity of the immune suppressor cells such as myeloid-derived suppressor cells (MDSC). Attempts to develop combinatorial therapies by depleting suppressor cells or blocking suppressor pathways and at …

Repertoire, Genealogy And Genomic Organization Of Cruzipain And Homologous Genes In Trypanosoma Cruzi, T. Cruzi-Like And Other Trypanosome Species, Luciana Lima, Paola A. Ortiz, Flavia M. Da Silva, Joao M. P. Alves, Myrna G. Serrano, Alane O. Cortez, Silvia C. Alfieri, Gregory A. Buck, Marta M. G. Teixeira

Microbiology and Immunology Publications

Trypanosoma cruzi, the agent of Chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to T. cruzi-like species, Trypanosoma cruzi marinkellei andTrypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. However, they differ in hosts, vectors and pathogenicity: T. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. Previous studies suggest that variations in expression levels and genetic diversity of cruzipain, the major isoform of cathepsin L-like (CATL) enzymes of T. cruzi, correlate with levels of cellular invasion, …

Adam10 Regulates Transcription Factor Expression Required For Plasma Cell Function, Natalia S. Chaimowitz, Dae-Joong Kang, Lee M. Dean, Daniel H. Conrad

Microbiology and Immunology Publications

A disintegrin and metalloprotease 10 (ADAM10) is a key regulator of cellular processes by shedding extracellular domains of transmembrane proteins. We have previously demonstrated that deletion of B cell expressed ADAM10 results in changes in lymphoid tissue architecture and impaired germinal center (GC) formation. In this study, mice were generated in which ADAM10 is deleted in B cells following class switch recombination (ADAM10Δ/ΔIgG1-cre+/−mice). Despite normal GC formation, antibody responses were impaired in ADAM10Δ/ΔIgG1-cre+/− mice, implicating ADAM10 in post-GC and extrafollicular B cell terminal differentiation. Surprisingly, plasma cell (PC) numbers were normal in ADAM10Δ/ΔIgG1-cre+/− mice when compared to controls. However, PCs …

Mouse Rc/Btb2, A Member Of The Rcc1 Superfamily, Localizes To Spermatid Acrosomal Vesicles, Jiannan Wang, Maria E. Teves, Xuening Shen, David R. Nagarkatti-Gude, Rex A. Hess, Scott C. Henderson, Jerome F. Strauss Iii, Zhibing Zhang

Obstetrics and Gynecology Publications

Mouse RC/BTB2 is an unstudied protein of the RCC1 (Regulator of Chromosome Condensation) superfamily. Because of the significant remodeling of chromatin that occurs during spermiogenesis, we characterized the expression and localization of mouse RC/BTB2 in the testis and male germ cells. The Rc/btb2 gene yields two major transcripts: 2.3 kb Rc/btb2-s, present in most somatic tissues examined; and 2.5 kb Rc/btb2-t, which contains a unique non-translated exon in its 5′-UTR that is only detected in the testis. During the first wave of spermatogenesis, Rc/btb2-t mRNA is expressed from day 8 after birth, reaching highest levels of expression at day …

Virginia Commonwealth University Graduate And Professional Programs Bulletin Courses [2012], Virginia Commonwealth University

VCU Bulletins

Listing of professional and graduate courses for 2012-2013

A Gga Plus U Approach To Effective Electronic Correlations In Thiolate-Ligated Iron-Oxo (Iv) Porphyrin, Justin Elenewski, John C. Hackett

Medicinal Chemistry Publications

High-valent oxo-metal complexes exhibit correlated electronic behavior on dense, low-lying electronic state manifolds, presenting challenging systems for electronic structure methods. Among these species, the iron-oxo (IV) porphyrin denoted Compound I occupies a privileged position, serving a broad spectrum of catalytic roles. The most reactive members of this family bear a thiolate axial ligand, exhibiting high activity toward molecular oxygen activation and substrate oxidation. The default approach to such systems has entailed the use of hybrid density functionals or multi-configurational/multireference methods to treat electronic correlation. An alternative approach is presented based on the GGA+U approximation to density functional theory, in …

Rsfa (Ybeb) Proteins Are Conserved Ribosomal Silencing Factors, Roman Hauser, Markus Pech, Jaroslaw Kijek, Hiroshi Yamamoto, Bjrn Titz, Florian Naeve, Andrey Tovchigrechko, Kaori Yamamoto, Witold Szaflarski, Nono Takeuchi, Thorsten Stellberger, Markus E. Diefenbacher, Knud H. Nierhaus, Peter Uetz

Study of Biological Complexity Publications

The YbeB (DUF143) family of uncharacterized proteins is encoded by almost all bacterial and eukaryotic genomes but not archaea. While they have been shown to be associated with ribosomes, their molecular function remains unclear. Here we show that YbeB is a ribosomal silencing factor (RsfA) in the stationary growth phase and during the transition from rich to poor media. A knock-out of the rsfA gene shows two strong phenotypes: (i) the viability of the mutant cells are sharply impaired during stationary phase (as shown by viability competition assays), and (ii) during transition from rich to poor media the mutant cells …

Minocycline Modulates Antigen-Specific Ctl Activity Through Inactivation Of Mononuclear Phagocytes In Patients With Htlv-I Associated Neurologic Disease, Yoshimi Enose-Akahata, Eiji Matsuura, Yuetsu Tanaka, Unsong Oh, Steven Jacobson

Neurology Publications

Background The activation of mononuclear phagocytes (MPs), including monocytes, macrophages and dendritic cells, contributes to central nervous system inflammation in various neurological diseases. In HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), MPs are reservoirs of HTLV-I, and induce proinflammatory cytokines and excess T cell responses. The virus-infected or activated MPs may play a role in immuneregulation and disease progression in patients with HTLV-I-associated neurological diseases.

Results Phenotypic analysis of CD14+ monocytes in HAM/TSP patients demonstrated high expression of CX3CR1 and HLA-DR in CD14lowCD16+ monocytes, compared to healthy normal donors (NDs) and asymptomatic carriers (ACs), and the production of TNF-α and IL-1β in …

Forward Euler Solutions And Weakly Invariant Time-Delayed Systems, Norma L. Ortiz-Robinson, Vinicio R. Ríos

Mathematics and Applied Mathematics Publications

This paper presents a necessary and sufficient condition for the weak invariance property of a time-delayed system parametrized by a differential inclusion. The aforementioned condition generalizes the well-known Hamilton-Jacobi inequality that characterizes weakly invariant systems in the nondelay setting. The forward Euler approximation scheme used in the theory of discontinuous differential equations is extended to the time-delayed context by incorporating the delay and tail functions featuring the dynamics. Accordingly, an existence theorem of weakly invariant trajectories is established under the extended forward Euler approach.

Rna-Seq Analysis Implicates Dysregulation Of The Immune System In Schizophrenia, Junzhe Xu, Jingchun Sun, Jingchun Chen, Lily Wang, Anna Li, Matthew Helm, Steven L. Dubovsky, Silviu-Alin Bacanu, Zhongming Zhao, Xiangning Chen

Psychiatry Publications

Background While genome-wide association studies identified some promising candidates for schizophrenia, the majority of risk genes remained unknown. We were interested in testing whether integration gene expression and other functional information could facilitate the identification of susceptibility genes and related biological pathways.

Results We conducted high throughput sequencing analyses to evaluate mRNA expression in blood samples isolated from 3 schizophrenia patients and 3 healthy controls. We also conducted pooled sequencing of 10 schizophrenic patients and matched controls. Differentially expressed genes were identified by t-test. In the individually sequenced dataset, we identified 198 genes differentially expressed between cases and controls, of …

Design Of An Implantable Device For Ocular Drug Delivery, Jae Hwan Lee, Ramana M. Pidiparti, Gary M. Atkinson, Ramana S. Moorthy

Mechanical and Nuclear Engineering Publications

Ocular diseases, such as, glaucoma, age-related macular degeneration (AMD), diabetic retinopathy, and retinitis pigmentosa require drug management in order to prevent blindness and affecting million of adults in USA and worldwide. There is an increasing need to develop devices for drug delivery to address ocular diseases. This study focuses on the design, simulation, and development of an implantable ocular drug delivery device consisting of micro-/nanochannels embedded between top and bottom covers with a drug reservoir made from polydimethylsiloxane (PDMS) which is silicon-based organic and biodegradable polymer. Several simulations were carried out with six different micro-channel configurations in order to see …

Identification And Structural Characterization Of A New Three-Finger Toxin Hemachatoxin From Hemachatus Haemachatus Venom, Vallerinteavide Mavelli Girish, Sundramurthy Kumar, Lissa Joseph, Chacko Jobichen, R. Manjunatha Kini, J. Sivaraman

Biochemistry and Molecular Biology Publications

Snake venoms are rich sources of biologically active proteins and polypeptides. Three-finger toxins are non-enzymatic proteins present in elapid (cobras, kraits, mambas and sea snakes) and colubrid venoms. These proteins contain four conserved disulfide bonds in the core to maintain the three-finger folds. Although all three-finger toxins have similar fold, their biological activities are different. A new three-finger toxin (hemachatoxin) was isolated from Hemachatus haemachatus (Ringhals cobra) venom. Its amino acid sequence was elucidated, and crystal structure was determined at 2.43 Å resolution. The overall fold is similar to other three-finger toxins. The structure and sequence analysis revealed that the …

Metabolic Rate Regulates L1 Longevity In C. Elegans, Inhwan Lee, Amber Hendrix, Jeongho Kim, Jennifer Yoshimoto, Young-Jai You

Biochemistry and Molecular Biology Publications

Animals have to cope with starvation. The molecular mechanisms by which animals survive long-term starvation, however, are not clearly understood. When they hatch without food, C. elegans arrests development at the first larval stage (L1) and survives more than two weeks. Here we show that the survival span of arrested L1s, which we call L1 longevity, is a starvation response regulated by metabolic rate during starvation. A high rate of metabolism shortens the L1 survival span, whereas a low rate of metabolism lengthens it. The longer worms are starved, the slower they grow once they are fed, suggesting that L1 …

Virginia Commonwealth University Undergraduate Bulletin [2012], Virginia Commonwealth University

VCU Bulletins

Undergraduate bulletin for Virginia Commonwealth University for the academic year 2012-2013. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for undergraduate programs.

Virginia Commonwealth University Undergraduate Bulletin Courses [2012], Virginia Commonwealth University

VCU Bulletins

Listing of undergraduate courses for 2012-2013.

Infantile Spasms (West Syndrome): Update And Resources For Pediatricians And Providers To Share With Parents, James W. Wheless, Patricia A. Gibson, Kari Luther Rosbeck, Maria Hardin, Christine O’Dell, Vicky Whittemore, John M. Pellock

Neurology Publications

Background Infantile spasms (IS; West syndrome) is a severe form of encephalopathy that typically affects infants younger than 2 years old. Pediatricians, pediatric neurologists, and other pediatric health care providers are all potentially key early contacts for families who have an infant with IS. The objective of this article is to assist pediatric health care providers in the detection of the disease and in the counseling and guidance of families who have an infant with IS.

Methods Treatment guidelines, consensus reports, and original research studies are reviewed to provide an update regarding the diagnosis and treatment of infants with IS. …

Prey Responses To Predator Chemical Cues: Disentangling The Importance Of The Number And Biomass Of Prey Consumed, Michael W. Mccoy, Justin C. Touchon, Tobias Landberg, Karen M. Warkentin, James R. Vonesh

Biology Publications

To effectively balance investment in predator defenses versus other traits, organisms must accurately assess predation risk. Chemical cues caused by predation events are indicators of risk for prey in a wide variety of systems, but the relationship between how prey perceive risk in relation to the amount of prey consumed by predators is poorly understood. While per capita predation rate is often used as the metric of relative risk, studies aimed at quantifying predator-induced defenses commonly control biomass of prey consumed as the metric of risk. However, biomass consumed can change by altering either the number or size of prey …

Transfer Student Peer Mentorship Initiative, Grace E. Harris Leadership Institute, Virginia Commonwealth University, Melinda Debrew, Artis Gordon, Rebecca Jones, Teri Kuttenkuler, Irene Lubker, Dewey Taylor

L. Douglas Wilder School of Government and Public Affairs Publications

Transfer students have unique needs that differ from those of incoming freshmen. The TRAM Transfer Student Mentorship Program connects incoming transfer students with students who also began their VCU journey as transfer students. Through a one-on-one relationship with a trained mentor, transfer students who participate in this program will access guidance and information to help them navigate the university and its resources, programs, and culture.

A Racial Impact Analysis Of Hb 462, Grace E. Harris Leadership Institute, Virginia Commonwealth University, Daphne Bryan, William Randolph, Tarvaris Mccoy

L. Douglas Wilder School of Government and Public Affairs Publications

The adoption of House Bill 462 into law brings forth questions about the probable impact on the physical, mental, emotional and financial well-being of the women in Virginia. In particular, analysis of its effect on the minority and underserved female population is required. Understanding the origin of this new legislation and the thinking behind its proposal and subsequent adoption dictates an endeavor into the backgrounds and intended goals of its sponsors and supporters. Proponents of HB 462 were unresponsive to requests for an interview to expound on their perspective about the importance of the legislation. This precipitated the use of …

Annual Higher Ground Women's Leadership Conference 2012, The Grace E. Harris Leadership Institute At Virginia Commonwealth University

The Grace E. Harris Leadership Institute Publications

No abstract provided.

Crystal Structures Of Human Pyridoxal Kinase In Complex With The Neurotoxins, Ginkgotoxin And Theophylline: Insights Into Pyridoxal Kinase Inhibition, Amit Gandhi, Jigar V. Desai, Mohini S. Ghatge, Martino L. Di Salvo, Stefano Di Biase, Richmond Danso-Danquah, Faik N. Musayev, Roberto Contestabile, Verne Schirch, Martin A. Safo

Medicinal Chemistry Publications

Several drugs and natural compounds are known to be highly neurotoxic, triggering epileptic convulsions or seizures, and causing headaches, agitations, as well as other neuronal symptoms. The neurotoxic effects of some of these compounds, including theophylline and ginkgotoxin, have been traced to their inhibitory activity against human pyridoxal kinase (hPL kinase), resulting in deficiency of the active cofactor form of vitamin B6, pyridoxal 5′-phosphate (PLP). Pyridoxal (PL), an inactive form of vitamin B6 is converted to PLP by PL kinase. PLP is the B6 vitamer required as a cofactor for over 160 enzymatic activities essential in primary and secondary metabolism. …

Discovery Of Prostamide F2Α And Its Role In Inflammatory Pain And Dorsal Horn Nociceptive Neuron Hyperexcitability, Luisa Gatta, Fabiana Piscitelli, Catia Giordano, Serana Boccella, Aron H. Lichtman, Sebatino Maione, Vincenzo Di Marzo

Pharmacology and Toxicology Publications

It was suggested that endocannabinoids are metabolized by cyclooxygenase (COX)-2 in the spinal cord of rats with kaolin/λ-carrageenan-induced knee inflammation, and that this mechanism contributes to the analgesic effects of COX-2 inhibitors in this experimental model. We report the development of a specific method for the identification of endocannabinoid COX-2 metabolites, its application to measure the levels of these compounds in tissues, and the finding of prostamide F2α (PMF2α) in mice with knee inflammation. Whereas the levels of spinal endocannabinoids were not significantly altered by kaolin/λ-carrageenan-induced knee inflammation, those of the COX-2 metabolite of AEA, PMF2α, were strongly elevated. The …

The Interleukin 3 Gene (Il3) Contributes To Human Brain Volume Variation By Regulating Proliferation And Survival Of Neural Progenitors, Xiao-Jian Luo, Ming Li, Liang Huang, Khwangsik Nho, Min Deng, Qiang Chen, Daniel R. Weinberger, Alejandro A. Vasquez, Mark Rijpkema, Venkata S. Mattay, Andrew J. Saykin, Li Shen, Guillen Fernandez, Barbara Franke, Jing-Chun Chen, Xiang-Ning Chen, Jin-Kai Wang, Xiao Xiao, Xue-Bin Qi, Kun Xiang, Ying-Mei Peng, Xiang-Yu Cao, Yi Li, Xiao-Dong Shi, Lin Gan, Bing Su

Psychiatry Publications

One of the most significant evolutionary changes underlying the highly developed cognitive abilities of humans is the greatly enlarged brain volume. In addition to being far greater than in most other species, the volume of the human brain exhibits extensive variation and distinct sexual dimorphism in the general population. However, little is known about the genetic mechanisms underlying normal variation as well as the observed sex difference in human brain volume. Here we show that interleukin-3 (IL3) is strongly associated with brain volume variation in four genetically divergent populations. We identified a sequence polymorphism (rs31480) in the IL3 promoter which …

Improving Intensity-Based Lung Ct Registration Accuracy Utilizing Vascular Information, Kunlin Cao, Kai Ding, Joseph M. Reinhardt, Gary E. Christensen

Radiation Oncology Publications

Accurate pulmonary image registration is a challenging problem when the lungs have a deformation with large distance. In this work, we present a nonrigid volumetric registration algorithm to track lung motion between a pair of intrasubject CT images acquired at different inflation levels and introduce a new vesselness similarity cost that improves intensity-only registration. Volumetric CT datasets from six human subjects were used in this study. The performance of four intensity-only registration algorithms was compared with and without adding the vesselness similarity cost function. Matching accuracy was evaluated using landmarks, vessel tree, and fissure planes. The Jacobian determinant of the …

Preserved Ex Vivo Inflammatory Status In Decidual Cells From Women With Preterm Labor And Subclinical Intrauterine Infection, Violeta Castro-Leyva, Aurora Espejel-Nunez, Gerardo Barroso, Veronica Zaga-Clavellina, Arturo Flores-Pliego, Iyari Morales-Mendez, Silvia Giono-Cerezo, Scott W. Walsh, Guadalupe Estrada-Gutierrez

Obstetrics and Gynecology Publications

Objective

To compare the inflammatory response preserved ex vivo by decidual cells isolated from women who experienced preterm labor with and without subclinical intrauterine infection.

Methods

Fetal membranes were obtained after cesarean section from 35 women who delivered before 37 weeks of gestation following spontaneous preterm labor, with no clinical evidence of intrauterine infection. Decidua was microbiologically tested and cultured. Concentrations of anti-inflammatory cytokines (IL-2, IL-4, IL-10), pro-inflammatory cytokines (IL-6, IL-8, IL-1β and TNF-α), and matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9) were measured in the supernatants using Bio-Plex, and prostaglandin E2 (PGE2) was measured by enzyme immunoassay.

Results …