Digital Commons Network^™

Identification And Phylogenetic Analysis Of Heme Synthesis Genes In Trypanosomatids And Their Bacterial Endosymbionts, João M. P. Alves, Logan Voegtly, Andrey V. Matveyev, Ana M. Lara, Flávia Maia Da Silva, Myrna G. Serrano, Gregory A. Buck, Marta M. G. Teixeira, Erney P. Camargo

Microbiology and Immunology Publications

It has been known for decades that some insect-infecting trypanosomatids can survive in culture without heme supplementation while others cannot, and that this capability is associated with the presence of a betaproteobacterial endosymbiont in the flagellate's cytoplasm. However, the specific mechanisms involved in this process remained obscure. In this work, we sequence and phylogenetically analyze the heme pathway genes from the symbionts and from their hosts, as well as from a number of heme synthesis-deficient Kinetoplastida. Our results show that the enzymes responsible for synthesis of heme are encoded on the symbiont genomes and produced in close cooperation with the …

Fetal Erap2 Variation Is Associated With Preeclampsia In African Americans In A Case-Control Study, Lori D. Hill, Dashaunda D. Hilliard, Timothy P. York, Sindhu Srinivas, Juan P. Kusanovic, Ricardo Gomez, Michal A. Elovitz, Roberto Romero, Jerome F. Strauss

Obstetrics and Gynecology Publications

Background Preeclampsia affects 3-8% of pregnancies and is a major cause of maternal and perinatal morbidity and mortality worldwide. This complex disorder is characterized by alterations in the immune and vascular systems and involves multiple organs. There is strong evidence for a genetic contribution to preeclampsia. Two different single nucleotide polymorphisms (SNPs) in the endoplasmic reticulum aminopeptidase 2 (ERAP2) gene were recently reported to be associated with increased risk for preeclampsia in two different populations. ERAP2 is expressed in placental tissue and it is involved in immune responses, inflammation, and blood pressure regulation; making it is an attractive preeclampsia candidate …

Epistasis Between Comt And Mthfr In Maternal-Fetal Dyads Increases Risk For Preeclampsia, Lori D. Hill, Timothy P. York, Juan P. Kusanovic, Ricardo Gomez, Lindon J. Eaves, Roberto Romero, Jerome F. Strauss Iii

Obstetrics and Gynecology Publications

Preeclampsia is a leading cause of perinatal morbidity and mortality. This disorder is thought to be multifactorial in origin, with multiple genes, environmental and social factors, contributing to disease. One proposed mechanism is placental hypoxia-driven imbalances in angiogenic and anti-angiogenic factors, causing endothelial cell dysfunction. Catechol-O-methyltransferase (Comt)-deficient pregnant mice have a preeclampsia phenotype that is reversed by exogenous 2-methoxyestradiol (2-ME), an estrogen metabolite generated by COMT. 2-ME inhibits Hypoxia Inducible Factor 1α, a transcription factor mediating hypoxic responses. COMT has been shown to interact with methylenetetrahydrofolate reductase (MTHFR), which modulates the availability of S-adenosylmethionine (SAM), a COMT …

Nitric Oxide Synthase Inhibition Enhances The Antitumor Effect Of Radiation In The Treatment Of Squamous Carcinoma Xenografts, Robert J. G. Cardnell, Ross B. Mikkelsen

Radiation Oncology Publications

This study tests whether the nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine (L-NNA), combines favorably with ionizing radiation (IR) in controlling squamous carcinoma tumor growth. Animals bearing FaDu and A431 xenografts were treated with L-NNA in the drinking water. IR exposure was 10 Gy for tumor growth and survival studies and 4 Gy for ex vivoclonogenic assays. Cryosections were examined immunohistochemically for markers of apoptosis and hypoxia. Blood flow was assayed by fluorescent microscopy of tissue cryosections after i.v. injection of fluorospheres. Orally administered L-NNA for 24 hrs reduces tumor blood flow by 80% (pex vivo clonogenic assay compared to …

Virginia Commonwealth University Undergraduate Bulletin Courses [2011], Virginia Commonwealth University

VCU Bulletins

Listing of undergraduate courses for 2011-2012.

Virginia Commonwealth University Graduate And Professional Programs Bulletin Courses [2011], Virginia Commonwealth University

VCU Bulletins

No abstract provided.

Virginia Commonwealth University Undergraduate Bulletin [2011], Virginia Commonwealth University

VCU Bulletins

Undergraduate bulletin for Virginia Commonwealth University for the academic year 2011-2012. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for undergraduate programs.

Virginia Commonwealth University Graduate And Professional Programs Bulletin [2011], Virginia Commonwealth University

VCU Bulletins

Graduate and professional programs bulletin for Virginia Commonwealth University for the academic year 2011-2012. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for graduate programs.

Applying An Empirical Hydropathic Forcefield In Refinement May Improve Low-Resolution Protein X-Ray Crystal Structures, Vishal N. Koparde, J. Neel Scarsdale, Glen E. Kellogg

Medicinal Chemistry Publications

Background

The quality of X-ray crystallographic models for biomacromolecules refined from data obtained at high-resolution is assured by the data itself. However, at low-resolution, >3.0 Å, additional information is supplied by a forcefield coupled with an associated refinement protocol. These resulting structures are often of lower quality and thus unsuitable for downstream activities like structure-based drug discovery.

Methodology

An X-ray crystallography refinement protocol that enhances standard methodology by incorporating energy terms from the HINT (Hydropathic INTeractions) empirical forcefield is described. This protocol was tested by refining synthetic low-resolution structural data derived from 25 diverse high-resolution structures, and referencing the resulting …

Spag16, An Axonemal Central Apparatus Gene, Encodes A Male Germ Cell Nuclear Speckle Protein That Regulates Spag16 Mrna Expression, David R. Nagarkatti-Gude, Ruth Jaimez, Scott C. Henderson, Maria E. Teves, Zhibing Zhang, Jerome F. Strauss Iii

Biochemistry and Molecular Biology Publications

Spag16 is the murine orthologue of Chlamydomonas reinhardtii PF20, a protein known to be essential to the structure and function of the “9+2” axoneme. In Chlamydomonas, the PF20gene encodes a single protein present in the central pair of the axoneme. Loss of PF20 prevents central pair assembly/integrity and results in flagellar paralysis. Here we demonstrate that the murine Spag16 gene encodes two proteins: 71 kDa SPAG16L, which is found in all murine cells with motile cilia or flagella, and 35 kDa SPAG16S, representing the C terminus of SPAG16L, which is expressed only in male germ cells, and is …

Development Of Melanopsin-Based Irradiance Detecting Circuitry, David S. Mcneill, Catherine J. Sheely, Jennifer L. Ecker, Tudor C. Badea, Duncan Morhardt, William Guido, Samer Hattar

Anatomy and Neurobiology Publications

Background

Most retinal ganglion cells (RGCs) convey contrast and motion information to visual brain centers. Approximately 2% of RGCs are intrinsically photosensitive (ipRGCs), express melanopsin and are necessary for light to modulate specific physiological processes in mice. The ipRGCs directly target the suprachiasmatic nucleus (SCN) to photoentrain circadian rhythms, and the olivary pretectal nucleus (OPN) to mediate the pupillary light response. How and when this ipRGC circuitry develops is unknown.

Results

Here, we show that some ipRGCs follow a delayed developmental time course relative to other image-forming RGCs. Specifically, ipRGC neurogenesis extends beyond that of other RGCs, and ipRGCs begin …

Enriching For Correct Prediction Of Biological Processes Using A Combination Of Diverse Classifiers, Daijin Ko, Brad Windle

Medicinal Chemistry Publications

Background Machine learning models (classifiers) for classifying genes to biological processes each have their own unique characteristics in what genes can be classified and to what biological processes. No single learning model is qualitatively superior to any other model and overall precision for each model tends to be low. The classification results for each classifier can be complementary and synergistic suggesting the benefit of a combination of algorithms, but often the prediction probability outputs of various learning models are neither comparable nor compatible for combining. A means to compare outputs regardless of the model and data used and combine the …

Antihypertensive Treatment Differentially Affects Vascular Sphingolipid Biology In Spontaneously Hypertensive Rats, Léon J. A. Spijkers, Ben J. A. Janssen, Jelly Nelissen, Merlijn J. P. M. T. Meens, Dayanjan Wijesinghe, Charles E. Chalfant, Jo G. R. De Mey, Astrid E. Alewijnse, Stephan L. M. Peters

Biochemistry and Molecular Biology Publications

We have previously shown that essential hypertension in humans and spontaneously hypertensive rats (SHR), is associated with increased levels of ceramide and marked alterations in sphingolipid biology. Pharmacological elevation of ceramide in isolated carotid arteries of SHR leads to vasoconstriction via a calcium-independent phospholipase A2, cyclooxygenase-1 and thromboxane synthase-dependent release of thromboxane A2. This phenomenon is almost absent in vessels from normotensive Wistar Kyoto (WKY) rats. Here we investigated whether lowering of blood pressure can reverse elevated ceramide levels and reduce ceramide-mediated contractions in SHR.

Methods and Findings

For this purpose SHR were treated for 4 weeks with the angiotensin …

Crystal Structure Of Thrombin In Complex With S-Variegin: Insights Of A Novel Mechanism Of Inhibition And Design Of Tunable Thrombin Inhibitors, Cho Yeow Koh, Sundramurthy Kumar, Maria Kazimirova, Patricia A. Nuttall, Uvaraj P. Radhakrishnan, Seongcheol Kim, Pudur Jagadeeswaran, Takayuki Imamura, Jun Mizuguchi, Sadaaki Iwanaga, Kunchithapadam Swaminathan, R. Manjunathan Kini

Biochemistry and Molecular Biology Publications

The inhibition of thrombin is one of the important treatments of pathological blood clot formation. Variegin, isolated from the tropical bont tick, is a novel molecule exhibiting a unique ‘two-modes’ inhibitory property on thrombin active site (competitive before cleavage, noncompetitive after cleavage). For the better understanding of its function, we have determined the crystal structure of the human α-thrombin:synthetic-variegin complex at 2.4 Å resolution. The structure reveals a new mechanism of thrombin inhibition by disrupting the charge relay system. Based on the structure, we have designed 17 variegin variants, differing in potency, kinetics and mechanism of inhibition. The most active …

Hypertension Is Associated With Marked Alterations In Sphingolipid Biology: A Potential Role For Ceramide, Leon J. A. Spijkers, Rob F. P. Van Den Akker, Ben J. A. Janssen, Jacques J. Debets, Jo G. R. De Mey, Erik S. G. Stroes, Bart-Jan H. Van Den Bom, Dayanjan Wijesinghe, Charles E. Chalfant, Luke Macaleese, Gert B. Eijkel, Ron M. A. Heeren, Astrid E. Alewijnse, Stephan L. M. Peters

Biochemistry and Molecular Biology Publications

Background

Hypertension is, amongst others, characterized by endothelial dysfunction and vascular remodeling. As sphingolipids have been implicated in both the regulation of vascular contractility and growth, we investigated whether sphingolipid biology is altered in hypertension and whether this is reflected in altered vascular function.

Methods and Findings

In isolated carotid arteries from spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats, shifting the ceramide/S1P ratio towards ceramide dominance by administration of a sphingosine kinase inhibitor (dimethylsphingosine) or exogenous application of sphingomyelinase, induced marked endothelium-dependent contractions in SHR vessels (DMS: 1.4±0.4 and SMase: 2.1±0.1 mN/mm; n = 10), that were virtually …

Behavior And Development Of Red-Eyed Treefrogs During Metamorphosis [Poster], Robin Greene, Clay Noss, Tobias Lanberg, James R. Vonesh, Karen Warkentin

Biology Presentations

Anuran metamorphosis is an extreme transformation from tadpole to frog that involves tremendous morphological and behavioral change. During this transition (Gosner stages 42-46), metamorphs are exposed to both aquatic and terrestrial selective pressures (e.g., predators, desiccation). Their behavior may be crucial for survival, but it is not well studied. Our goal was to describe morphological and behavioral patterns during metamorphosis in red-eyed treefrogs, Agalychnis callidryas. We first quantified development through metamorphosis by measuring and staging 25 wild-caught individuals every 8 h. We then conducted field behavioral observations of 37 metamorphs, at various developmental stages, that had emerged from a …

The Cost Of Hatching Early: Vulnerability And Exposure To Predators [Poster], M. S. Palmer, B. Willink, T. Landberg, James R. Vonesh, K. M. Warkentin

Biology Presentations

Arboreal red-eyed treefrog embryos can hatch prematurely in response to egg predators. Induced early hatchlings face aquatic predators when less developed and for longer than do later hatchlings; both factors may alter survival through the high-risk early larval period. Prior work focused on developmental effects of induced hatching. In 24 h trials, less developed hatchlings were more vulnerable to three aquatic predators (shrimp, fish, water bugs) but had similar or better survival than full-term hatchlings with libellulid and aeschnid dragonfly nymphs. However, it is unknown how developmental effects and duration of exposure to predators combine to create the net effect …

Habitat Use And Population Densities Of Rain Forest Chameleons In The East Usambara Mountains Of Tanzania [Poster], Philip Shirk, David A. Patrick, James R. Vonesh, Kim Howell

Biology Presentations

Conclusions:

• Chamaeleo dilepis and Ri. brevicaudatus are absent from forest at this elevation (852-1103m), while K. matschiei, K. vosseleri, K. tenuis, and R. spinosus are relatively scarce in the forest. Trioceros deremensis and R. temporalis are common, but density varies greatly.
• The endemic and scarce K. matschiei and K. vosseleri may be of concern given their scarcity in forest habitat. Density estimates in other habitat types are needed to determine status.
• For accurate density estimates, it is important to consider seasonal variation in density and animals too high to be observed in surveys.

Tadpole Density Changes The Relationship Of Red-Eyed Treefrog Morphology And Jumping Performance [Poster], Julie Charbonnier, T. Landberg

Biology Presentations

As organisms develop, increased body size is often accompanied by shape changes that alter the morphology–performance relationship. Animals with different growth histories may also have different shapes at similar body sizes. To investigate how larval growth history affects the morphology–performance relationship, we raised red-eyed treefrog tadpoles (Agalychnis callidryas) at three densities (5, 25 and 50 tadpoles per 400 L tank) and measured jump distance during metamorphosis. We predicted that tadpoles grown at low density would metamorphose into larger frogs with relatively longer legs than those grown at higher densities. We also expected low density frogs to jump further …

Effects Of Hatching Timing On Red-Eyed Treefrog Tadpoles: Relative Vulnerability Varies Among Predators But Not With Hatchling Age-Structure, Growth Varies With The Presence Of More Vulnerable Tadpoles [Poster], B. Willink, T. Landberg, James R. Vonesh, K. M. Warkentin

Biology Presentations

In Gamboa, Panama, undisturbed red-eyed treefrog embryos typically hatch at age 6 days, but they can hatch as early as 4 days if attacked by egg predators. Early hatchlings are less developed and more vulnerable to predatory shrimp and fish. Here we assess the effect of hatching timing on risk of predation by three common insects, with different foraging styles, that prey on red-eyed treefrog larvae. Further, we examine whether the consequences of hatching early vary with the presence of later-hatched tadpoles. We induced hatching at 4 and 6 days and exposed tadpoles to giant water bugs or aeshnid or …

An Intermediate In The Evolution Of Superfast Sonic Muscles., Hin-Kiu Mok, Eric Parmentier, Kuo-Hsun Chiu, Michael L. Fine

Biology Publications

Background

Intermediate forms in the evolution of new adaptations such as transitions from water to land and the evolution of flight are often poorly understood. Similarly, the evolution of superfast sonic muscles in fishes, often considered the fastest muscles in vertebrates, has been a mystery because slow bladder movement does not generate sound. Slow muscles that stretch the swimbladder and then produce sound during recoil have recently been discovered in ophidiiform fishes. Here we describe the disturbance call (produced when fish are held) and sonic mechanism in an unrelated perciform pearl perch (Glaucosomatidae) that represents an intermediate condition in the …

Virginia Commonwealth University Fall Commencement Program [2011], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

Er Stress And Lipid Metabolism In Adipocytes, Beth S. Zha, Huiping Zhou

Microbiology and Immunology Publications

The role of endoplasmic reticulum (ER) stress is a rapidly emerging field of interest in the pathogenesis of metabolic diseases. Recent studies have shown that chronic activation of ER stress is closely linked to dysregulation of lipid metabolism in several metabolically important cells including hepatocytes, macrophages, β-cells, and adipocytes. Adipocytes are one of the major cell types involved in the pathogenesis of the metabolic syndrome. Recent advances in dissecting the cellular and molecular mechanisms involved in the regulation of adipogenesis and lipid metabolism indicate that activation of ER stress plays a central role in regulating adipocyte function. In this paper, …

Outlier-Resistant L1 Orthogonal Regression Via The Reformulation-Linearization Technique, J. Paul Brooks, Edward L. Boone

Statistical Sciences and Operations Research Publications

Assessing the linear relationship between a set of continuous predictors and a continuous response is a well-studied problem in statistics and data mining. L2-based methods such as ordinary least squares and orthogonal regression can be used to determine this relationship. However, both of these methods become impaired when influential values are present. This problem becomes compounded when outliers confound standard diagnostics. This work proposes an L1-norm orthogonal regression method (L1OR) formulated as a nonconvex optimization problem. Solution strategies for finding globally optimal solutions are presented. Simulation studies are conducted to assess the resistance of the method to outliers and the …

Tunable And Abrupt Thermal Quenching Of Photoluminescence In High-Resistivity Zn-Doped Gan, Michael A. Reshchikov, Alexander A. Kvasov, Marilyn F. Bishop, Tom Mcmullen, Alexander Usikov, Vitali Soukhoveev, Vladimir A. Dmitriev

Physics Publications

Tunable and abrupt thermal quenching of photoluminescence by increasing temperature has been observed for the blue band in high-resistivity Zn-doped GaN. The photoluminescence intensity dropped by several orders of magnitude within a few Kelvins, and the temperature at which that drop occurred could be tuned by changing the incident light intensity. Modeling the system with rate equations for competing electron-hole recombination flows through three defect species, one of which is a nonradiative deep donor, gives results consistent with these observations.

Intravaginal Cytomegalovirus (Cmv) Challenge Elicits Maternal Viremia And Results In Congenital Transmission In A Guinea Pig Model, Megan J. Olejniczak, K Yeon Choi, Michael Mcvoy, Xiaohong Cui, Mark R. Schleiss

Pediatrics Publications

Background The objective of this study was to compare intravaginal (ivg) and subcutaneous (sc) administration of the guinea pig cytomegalovirus (GPCMV) in pregnant and non-pregnant guinea pigs. These studies tested the hypotheses that ivg infection would elicit immune responses, produce maternal viremia, and lead to vertical transmission, with an efficiency similar to the traditionally employed sc route.

Results Four groups of age- and size-matched guinea pigs were studied. Two groups were pregnant, and two groups were not pregnant. Animals received 5x105 plaque-forming units (PFU) of a GPCMV reconstituted from an infectious bacterial artificial chromosome (BAC) construct containing the full-length GPCMV …

The Protein Interaction Map Of Bacteriophage Lambda, Seesandra V. Rajagopala, Sherwood Casjens, Peter Uetz

Study of Biological Complexity Publications

Background

Bacteriophage lambda is a model phage for most other dsDNA phages and has been studied for over 60 years. Although it is probably the best-characterized phage there are still about 20 poorly understood open reading frames in its 48-kb genome. For a complete understanding we need to know all interactions among its proteins. We have manually curated the lambda literature and compiled a total of 33 interactions that have been found among lambda proteins. We set out to find out how many protein-protein interactions remain to be found in this phage.

Results

In order to map lambda's interactions, we …

Nordp News 1.1, National Organization Of Research Development Professionals, Jeffrey M. Anderson (Ed.)

Research Development Repository

This is an upload of a past issue of the NORDP News Newsletter. The table of contents includes:

• The President’s Corner
• The Explosion of Research Development
• NORDP 2011 in Pictures
• NORDP Working Group Updates
• NORDP by the Numbers
• NORDP Spotlight: Can Research Develop Save Academia?
• The Inside Story: Floating Research in a Drowning Economy
• Research Development Articles
• Upcoming Research Development Conferences
• NORDP Members in the News
• Research Development Jobs Sampler

Dressed To Cross: Narratives Of Resistance And Integration In Sei Shônagon's The Pillow Book And Yone Noguchi's The American Diary Of A Japanese Girl, Ina Christiane Seethaler

Ethnic Studies Review

The Pillow Book by Sei Shônagon, Empress Sadako's lady in waiting from about 993-1000, offers rich detail about the meaning and power of dress during the Heian period [794-1185]. Throughout Yone Noguchi's novel The American Diary of a Japanese Girl (1902), Morning Glory, a newly arrived Japanese immigrant to the U.S., experiments with a multitude of different identities through clothes. Both narratives appropriate (cross-) dressing as a means of overcoming gender, cultural, and class borders. Shônagon and Noguchi engage in "authorial crossdressing" to inhabit a social, cultural, and national space onto which they only have a precarious hold. It is …

¡Pendejo! Preschoolers’ Profane Play: Why Children Make Art, Marissa Mcclure

Journal of Social Theory in Art Education

In this article, I address the concept of critical coalitions in play from two perspectives. First, I consider young children’s art making with digital video through contemporary play frames that propose moving beyond the dichotomy of subject (child as actor; active meaning-maker) and object (child as dupe; susceptible to media and moral panic). This reaffirms that play is at once contradictory, pleasurable, fantastic, and culturally purposeful. Analysis of young children’s digital video as play within frameworks proposed by Wilson (1976), Walkerdine (2007), and Freud (1922/1948) allows for an expansion of philosophical ideas about young children’s art making. This coalition between …