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Enhanced Estrogen-Induced Proliferation In Obese Rat Endometrium, Qian Zhang, Qi Shen, Joseph Celestino, Michael R Milam, Shannon N Westin, Robin A Lacour, Larissa A Meyer, Gregory L Shipley, Peter J A Davies, Lei Deng, Adrienne S Mccampbell, Russell R Broaddus, Karen H Lu Feb 2009

Enhanced Estrogen-Induced Proliferation In Obese Rat Endometrium, Qian Zhang, Qi Shen, Joseph Celestino, Michael R Milam, Shannon N Westin, Robin A Lacour, Larissa A Meyer, Gregory L Shipley, Peter J A Davies, Lei Deng, Adrienne S Mccampbell, Russell R Broaddus, Karen H Lu

Faculty, Staff and Student Publications

OBJECTIVE: We tested the hypothesis that the proliferative estrogen effect on the endometrium is enhanced in obese vs lean animals.

STUDY DESIGN: Using Zucker fa/fa obese rats and lean control, we examined endometrial cell proliferation and the expression patterns of certain estrogen-regulated proproliferative and antiproliferative genes after short-term treatment with estradiol.

RESULTS: No significant morphologic/histologic difference was seen between the obese rats and the lean rats. Estrogen-induced proproliferative genes cyclin A and c-Myc messenger RNA expression were significantly higher in the endometrium of obese rats compared with those of the lean control. Expression of the antiproliferative gene p27Kip1 was suppressed …


Genetic And Hormonal Factors Modulate Spreading Depression And Transient Hemiparesis In Mouse Models Of Familial Hemiplegic Migraine Type 1, Katharina Eikermann-Haerter, Ergin Dileköz, Chiho Kudo, Sean I Savitz, Christian Waeber, Michael J Baum, Michel D Ferrari, Arn M J M Van Den Maagdenberg, Michael A Moskowitz, Cenk Ayata Jan 2009

Genetic And Hormonal Factors Modulate Spreading Depression And Transient Hemiparesis In Mouse Models Of Familial Hemiplegic Migraine Type 1, Katharina Eikermann-Haerter, Ergin Dileköz, Chiho Kudo, Sean I Savitz, Christian Waeber, Michael J Baum, Michel D Ferrari, Arn M J M Van Den Maagdenberg, Michael A Moskowitz, Cenk Ayata

Faculty, Staff and Student Publications

Familial hemiplegic migraine type 1 (FHM1) is an autosomal dominant subtype of migraine with aura that is associated with hemiparesis. As with other types of migraine, it affects women more frequently than men. FHM1 is caused by mutations in the CACNA1A gene, which encodes the alpha1A subunit of Cav2.1 channels; the R192Q mutation in CACNA1A causes a mild form of FHM1, whereas the S218L mutation causes a severe, often lethal phenotype. Spreading depression (SD), a slowly propagating neuronal and glial cell depolarization that leads to depression of neuronal activity, is the most likely cause of migraine aura. Here, we have …


Ca125/Muc16 Is Dispensable For Mouse Development And Reproduction, Dong-Joo Cheon, Ying Wang, Jian Min Deng, Zhen Lu, Lianchun Xiao, Chun-Ming Chen, Robert C Bast, Richard R Behringer Jan 2009

Ca125/Muc16 Is Dispensable For Mouse Development And Reproduction, Dong-Joo Cheon, Ying Wang, Jian Min Deng, Zhen Lu, Lianchun Xiao, Chun-Ming Chen, Robert C Bast, Richard R Behringer

Faculty, Staff and Student Publications

Cancer antigen 125 (CA125) is a blood biomarker that is routinely used to monitor the progression of human epithelial ovarian cancer (EOC) and is encoded by MUC16, a member of the mucin gene family. The biological function of CA125/MUC16 and its potential role in EOC are poorly understood. Here we report the targeted disruption of the of the Muc16 gene in the mouse. To generate Muc16 knockout mice, 6.0 kb was deleted that included the majority of exon 3 and a portion of intron 3 and replaced with a lacZ reporter cassette. Loss of Muc16 protein expression suggests that Muc16 …


Upregulation Of Defensins In Burn Sheep Small Intestine, Brian J Poindexter, Gordon L Klein, Stephen M Milner, Roger J Bick Jan 2009

Upregulation Of Defensins In Burn Sheep Small Intestine, Brian J Poindexter, Gordon L Klein, Stephen M Milner, Roger J Bick

Faculty, Staff and Student Publications

OBJECTIVE: The aim of this study was to visualize and localize the sheep antimicrobials, beta-defensins 1, 2, and 3, (SBD-1, SBD-2, SBD-3), sheep neutrophil defensin alpha (SNP-1), and the cathelicidin LL-37 in sheep small intestine after burn injury, our hypothesis being that these compounds would be upregulated in an effort to overcome a compromised endothelial lining. Response to burn injury includes the release of proinflammatory cytokines and systemic immune suppression that, if untreated, can progress to multiple organ failure and death, so protective mechanisms have to be initiated and implemented.

METHODS: Tissue sections were probed with antibodies to the antimicrobials …


Structure Altering Effects Of A Multicomponent Reading Intervention: An Application Of The Direct And Inferential Mediation (Dime) Model Of Reading Comprehension In Upper Elementary Grades, Georgios Kalantzis, Harel Z Shouval Jan 2009

Structure Altering Effects Of A Multicomponent Reading Intervention: An Application Of The Direct And Inferential Mediation (Dime) Model Of Reading Comprehension In Upper Elementary Grades, Georgios Kalantzis, Harel Z Shouval

Faculty, Staff and Student Publications

BACKGROUND: Synaptic plasticity underlies many aspect of learning memory and development. The properties of synaptic plasticity can change as a function of previous plasticity and previous activation of synapses, a phenomenon called metaplasticity. Synaptic plasticity not only changes the functional connectivity between neurons but in some cases produces a structural change in synaptic spines; a change thought to form a basis for this observed plasticity. Here we examine to what extent structural plasticity of spines can be a cause for metaplasticity. This study is motivated by the observation that structural changes in spines are likely to affect the calcium dynamics …


Molluscan Memory Of Injury: Evolutionary Insights Into Chronic Pain And Neurological Disorders, Edgar T Walters, Leonid L Moroz Jan 2009

Molluscan Memory Of Injury: Evolutionary Insights Into Chronic Pain And Neurological Disorders, Edgar T Walters, Leonid L Moroz

Faculty, Staff and Student Publications

Molluscan preparations have yielded seminal discoveries in neuroscience, but the experimental advantages of this group have not, until now, been complemented by adequate molecular or genomic information for comparisons to genetically defined model organisms in other phyla. The recent sequencing of the transcriptome and genome of Aplysia californica, however, will enable extensive comparative studies at the molecular level. Among other benefits, this will bring the power of individually identifiable and manipulable neurons to bear upon questions of cellular function for evolutionarily conserved genes associated with clinically important neural dysfunction. Because of the slower rate of gene evolution in this molluscan …


Is Paromomycin An Effective And Safe Treatment Against Cutaneous Leishmaniasis? A Meta-Analysis Of 14 Randomized Controlled Trials, Dae Hyun Kim, Hye Jin Chung, Joachim Bleys, Reza F Ghohestani Jan 2009

Is Paromomycin An Effective And Safe Treatment Against Cutaneous Leishmaniasis? A Meta-Analysis Of 14 Randomized Controlled Trials, Dae Hyun Kim, Hye Jin Chung, Joachim Bleys, Reza F Ghohestani

Faculty, Staff and Student Publications

BACKGROUND: High cost, poor compliance, and systemic toxicity have limited the use of pentavalent antimony compounds (SbV), the treatment of choice for cutaneous leishmaniasis (CL). Paromomycin (PR) has been developed as an alternative to SbV, but existing data are conflicting.

METHODOLOGY/PRINCIPAL FINDINGS: We searched PubMed, Scopus, and Cochrane Central Register of Controlled Trials, without language restriction, through August 2007, to identify randomized controlled trials that compared the efficacy or safety between PR and placebo or SbV. Primary outcome was clinical cure, defined as complete healing, disappearance, or reepithelialization of all lesions. Data were extracted independently by two investigators, and pooled …


Increased Myocardial Susceptibility To Repetitive Ischemia With High-Fat–Diet-Induced Obesity, Geeta D Thakker, Nikolaos G Frangogiannis, Pawel T Zymek, Saumya Sharma, Joe L Raya, Philip M Barger, Heinrich Taegtmeyer, Mark L Entman, Christie M Ballantyne Dec 2008

Increased Myocardial Susceptibility To Repetitive Ischemia With High-Fat–Diet-Induced Obesity, Geeta D Thakker, Nikolaos G Frangogiannis, Pawel T Zymek, Saumya Sharma, Joe L Raya, Philip M Barger, Heinrich Taegtmeyer, Mark L Entman, Christie M Ballantyne

Faculty, Staff and Student Publications

Obesity and diabetes are frequently associated with cardiovascular disease. When a normal heart is subjected to brief/sublethal repetitive ischemia and reperfusion (I/R), adaptive responses are activated to preserve cardiac structure and function. These responses include but are not limited to alterations in cardiac metabolism, reduced calcium responsiveness, and induction of antioxidant enzymes. In a model of ischemic cardiomyopathy inducible by brief repetitive I/R, we hypothesized that dysregulation of these adaptive responses in diet-induced obese (DIO) mice would contribute to enhanced myocardial injury. DIO C57BL/6J mice were subjected to 15 min of daily repetitive I/R while under short-acting anesthesia, a protocol …


Coordinated Changes In Mrna Turnover, Translation, And Rna Processing Bodies In Bronchial Epithelial Cells Following Inflammatory Stimulation, Yuxin Zhai, Zhenping Zhong, Chyi-Ying A Chen, Zhenfang Xia, Ling Song, Michael R Blackburn, Ann-Bin Shyu Dec 2008

Coordinated Changes In Mrna Turnover, Translation, And Rna Processing Bodies In Bronchial Epithelial Cells Following Inflammatory Stimulation, Yuxin Zhai, Zhenping Zhong, Chyi-Ying A Chen, Zhenfang Xia, Ling Song, Michael R Blackburn, Ann-Bin Shyu

Faculty, Staff and Student Publications

Bronchial epithelial cells play a pivotal role in airway inflammation, but little is known about posttranscriptional regulation of mediator gene expression during the inflammatory response in these cells. Here, we show that activation of human bronchial epithelial BEAS-2B cells by proinflammatory cytokines interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-alpha) leads to an increase in the mRNA stability of the key chemokines monocyte chemotactic protein 1 and IL-8, an elevation of the global translation rate, an increase in the levels of several proteins critical for translation, and a reduction of microRNA-mediated translational repression. Moreover, using the BEAS-2B cell system and …


Extended Kalman Filter For Estimation Of Parameters In Nonlinear State-Space Models Of Biochemical Networks, Xiaodian Sun, Li Jin, Momiao Xiong Nov 2008

Extended Kalman Filter For Estimation Of Parameters In Nonlinear State-Space Models Of Biochemical Networks, Xiaodian Sun, Li Jin, Momiao Xiong

Faculty, Staff and Student Publications

It is system dynamics that determines the function of cells, tissues and organisms. to develop mathematical models and estimate their parameters are an essential issue for studying dynamic behaviors of biological systems which include metabolic networks, genetic regulatory networks and signal transduction pathways, under perturbation of external stimuli. In general, biological dynamic systems are partially observed. Therefore, a natural way to model dynamic biological systems is to employ nonlinear state-space equations. Although statistical methods for parameter estimation of linear models in biological dynamic systems have been developed intensively in the recent years, the estimation of both states and parameters of …


Mrsa Usa300 Clone And Vref--A Us-Colombian Connection?, Cesar A Arias, Sandra Rincon, Shahreen Chowdhury, Ernesto Martínez, Wilfrido Coronell, Jinnethe Reyes, Sreedhar R Nallapareddy, Barbara E Murray Nov 2008

Mrsa Usa300 Clone And Vref--A Us-Colombian Connection?, Cesar A Arias, Sandra Rincon, Shahreen Chowdhury, Ernesto Martínez, Wilfrido Coronell, Jinnethe Reyes, Sreedhar R Nallapareddy, Barbara E Murray

Faculty, Staff and Student Publications

No abstract provided.


Foxm1b Transcriptionally Regulates Vascular Endothelial Growth Factor Expression And Promotes The Angiogenesis And Growth Of Glioma Cells, Yujian Zhang, Nu Zhang, Bingbing Dai, Mingguang Liu, Raymond Sawaya, Keping Xie, Suyun Huang Nov 2008

Foxm1b Transcriptionally Regulates Vascular Endothelial Growth Factor Expression And Promotes The Angiogenesis And Growth Of Glioma Cells, Yujian Zhang, Nu Zhang, Bingbing Dai, Mingguang Liu, Raymond Sawaya, Keping Xie, Suyun Huang

Faculty, Staff and Student Publications

We previously found that FoxM1B is overexpressed in human glioblastomas and that forced FoxM1B expression in anaplastic astrocytoma cells leads to the formation of highly angiogenic glioblastoma in nude mice. However, the molecular mechanisms by which FoxM1B enhances glioma angiogenesis are currently unknown. In this study, we found that vascular endothelial growth factor (VEGF) is a direct transcriptional target of FoxM1B. FoxM1B overexpression increased VEGF expression, whereas blockade of FoxM1 expression suppressed VEGF expression in glioma cells. Transfection of FoxM1 into glioma cells directly activated the VEGF promoter, and inhibition of FoxM1 expression by FoxM1 siRNA suppressed VEGF promoter activation. …


Rationale For Reading Fluconazole Mics At 24 Hours Rather Than 48 Hours When Testing Candida Spp By The Clsi M27-A2 Standard Method, Luis Ostrosky-Zeichner, John H Rex, Michael A Pfaller, Daniel J Diekema, Barbara D Alexander, David Andes, Steven D Brown, Vishnu Chaturvedi, Mahmoud A Ghannoum, Cindy C Knapp, Daniel J Sheehan, Thomas J Walsh Nov 2008

Rationale For Reading Fluconazole Mics At 24 Hours Rather Than 48 Hours When Testing Candida Spp By The Clsi M27-A2 Standard Method, Luis Ostrosky-Zeichner, John H Rex, Michael A Pfaller, Daniel J Diekema, Barbara D Alexander, David Andes, Steven D Brown, Vishnu Chaturvedi, Mahmoud A Ghannoum, Cindy C Knapp, Daniel J Sheehan, Thomas J Walsh

Faculty, Staff and Student Publications

We investigated if CLSI M27-A2 Candida species breakpoints for fluconazole MIC are valid when read at 24 h. Analysis of a data set showed good correlation between 48- and 24-h MICs, as well as similar outcomes and pharmacodynamic efficacy parameters, except for isolates in the susceptible dose-dependent category, such as Candida glabrata.


Syntaxin 3b Is Essential For The Exocytosis Of Synaptic Vesicles In Ribbon Synapses Of The Retina, Leigh B Curtis, Blair Doneske, Xiaoqin Liu, Christina Thaller, James A Mcnew, Roger Janz Oct 2008

Syntaxin 3b Is Essential For The Exocytosis Of Synaptic Vesicles In Ribbon Synapses Of The Retina, Leigh B Curtis, Blair Doneske, Xiaoqin Liu, Christina Thaller, James A Mcnew, Roger Janz

Faculty, Staff and Student Publications

Previous studies have demonstrated that ribbon synapses in the retina do not contain the t-SNARE (target-soluble N-ethylmaleimide-sensitive factor attachment protein receptor) syntaxin 1A that is found in conventional synapses of the nervous system. In contrast, ribbon synapses of the retina contain the related isoform syntaxin 3. In addition to its localization in ribbon synapses, syntaxin 3 is also found in nonneuronal cells, where it has been implicated in the trafficking of transport vesicles to the apical plasma membrane of polarized cells. The syntaxin 3 gene codes for four different splice forms, syntaxins 3A, 3B, 3C, and 3D. We demonstrate here …


The Untapped Power Of "We Don't Know": Epistemological Humility In The Era Of Covid-19, Diasinou Fioravante, Rong-Yu Liu, John H. Byrne Oct 2008

The Untapped Power Of "We Don't Know": Epistemological Humility In The Era Of Covid-19, Diasinou Fioravante, Rong-Yu Liu, John H. Byrne

Faculty, Staff and Student Publications

The neuropeptide Phe-Met-Arg-Phe-NH(2) (FMRFa) can induce transcription-dependent long-term synaptic depression (LTD) in Aplysia sensorimotor synapses. We investigated the role of the ubiquitin-proteasome system and the regulation of one of its components, ubiquitin C-terminal hydrolase (ap-uch), in LTD. LTD was sensitive to presynaptic inhibition of the proteasome and was associated with upregulation of ap-uch mRNA and protein. This upregulation appeared to be mediated by CREB2, which is generally regarded as a transcription repressor. Binding of CREB2 to the promoter region of ap-uch was accompanied by histone hyperacetylation, suggesting that CREB2 cannot only inhibit but also promote gene expression. CREB2 was phosphorylated …


Role Of The N- And C-Lobes Of Calmodulin In The Activation Of Ca2+/Calmodulin-Dependent Protein Kinase Ii, Amelie Forest, Matthew T Swulius, Joyce K Y Tse, J Michael Bradshaw, Tara Gaertner, M Neal Waxham Oct 2008

Role Of The N- And C-Lobes Of Calmodulin In The Activation Of Ca2+/Calmodulin-Dependent Protein Kinase Ii, Amelie Forest, Matthew T Swulius, Joyce K Y Tse, J Michael Bradshaw, Tara Gaertner, M Neal Waxham

Faculty, Staff and Student Publications

Understanding the principles of calmodulin (CaM) activation of target enzymes will help delineate how this seemingly simple molecule can play such a complex role in transducing Ca (2+)-signals to a variety of downstream pathways. In the work reported here, we use biochemical and biophysical tools and a panel of CaM constructs to examine the lobe specific interactions between CaM and CaMKII necessary for the activation and autophosphorylation of the enzyme. Interestingly, the N-terminal lobe of CaM by itself was able to partially activate and allow autophosphorylation of CaMKII while the C-terminal lobe was inactive. When used together, CaMN and CaMC …


Characteristics Of A Spina Bifida Population Including North American Caucasian And Hispanic Individuals, Kit Sing Au, Phong X Tran, Chester C Tsai, Michelle R O'Byrne, Jone-Ing Lin, Alanna C Morrison, Amy W Hampson, Paul Cirino, Jack M Fletcher, Kathryn K Ostermaier, Gayle H Tyerman, Sabine Doebel, Hope Northrup Oct 2008

Characteristics Of A Spina Bifida Population Including North American Caucasian And Hispanic Individuals, Kit Sing Au, Phong X Tran, Chester C Tsai, Michelle R O'Byrne, Jone-Ing Lin, Alanna C Morrison, Amy W Hampson, Paul Cirino, Jack M Fletcher, Kathryn K Ostermaier, Gayle H Tyerman, Sabine Doebel, Hope Northrup

Faculty, Staff and Student Publications

BACKGROUND: Meningomyelocele (MM) is a common human birth defect. MM is a disorder of neural development caused by contributions from genes and environmental factors that result in the NTD and lead to a spectrum of physical and neurocognitive phenotypes.

METHODS: A multidisciplinary approach has been taken to develop a comprehensive understanding of MM through collaborative efforts from investigators specializing in genetics, development, brain imaging, and neurocognitive outcome. Patients have been recruited from five different sites: Houston and the Texas-Mexico border area; Toronto, Canada; Los Angeles, California; and Lexington, Kentucky. Genetic risk factors for MM have been assessed by genotyping and …


Molecular And Macromolecular Alterations Of Recombinant Adenoviral Vectors Do Not Resolve Changes In Hepatic Drug Metabolism During Infection, Shellie M Callahan, Piyanuch Wonganan, Maria A Croyle Sep 2008

Molecular And Macromolecular Alterations Of Recombinant Adenoviral Vectors Do Not Resolve Changes In Hepatic Drug Metabolism During Infection, Shellie M Callahan, Piyanuch Wonganan, Maria A Croyle

Faculty, Staff and Student Publications

In this report we test the hypothesis that long-term virus-induced alterations in CYP occur from changes initiated by the virus that may not be related to the immune response. Enzyme activity, protein expression and mRNA of CYP3A2, a correlate of human CYP3A4, and CYP2C11, responsive to inflammatory mediators, were assessed 0.25, 1, 4, and 14 days after administration of several different recombinant adenoviruses at a dose of 5.7 x 1012 virus particles (vp)/kg to male Sprague Dawley rats. Wild type adenovirus, containing all viral genes, suppressed CYP3A2 and 2C11 activity by 37% and 39%, respectively within six hours. Levels fell …


Substance Use Among Persons With Syphilis During Pregnancy — Arizona And Georgia, 2018–2021, Lingpeng Cheng, Qin Fang, Sanket Shah, Ivo C Atanasov, Z Hong Zhou Sep 2008

Substance Use Among Persons With Syphilis During Pregnancy — Arizona And Georgia, 2018–2021, Lingpeng Cheng, Qin Fang, Sanket Shah, Ivo C Atanasov, Z Hong Zhou

Faculty, Staff and Student Publications

Grass carp reovirus (GCRV) is a member of the Aquareovirus genus of the family Reoviridae, a large family of double-stranded RNA (dsRNA) viruses infecting plants, insects, fishes and mammals. We report the first subnanometer-resolution three-dimensional structures of both GCRV core and virion by cryoelectron microscopy. These structures have allowed the delineation of interactions among the over 1000 molecules in this enormous macromolecular machine and a detailed comparison with other dsRNA viruses at the secondary-structure level. The GCRV core structure shows that the inner proteins have strong structural similarities with those of orthoreoviruses even at the level of secondary-structure elements, indicating …


Molecular Mechanisms Underlying A Cellular Analog Of Operant Reward Learning, Fred D Lorenzetti, Douglas A Baxter, John H Byrne Sep 2008

Molecular Mechanisms Underlying A Cellular Analog Of Operant Reward Learning, Fred D Lorenzetti, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

Operant conditioning is a ubiquitous but mechanistically poorly understood form of associative learning in which an animal learns the consequences of its behavior. Using a single-cell analog of operant conditioning in neuron B51 of Aplysia, we examined second-messenger pathways engaged by activity and reward and how they may provide a biochemical association underlying operant learning. Conditioning was blocked by Rp-cAMP, a peptide inhibitor of PKA, a PKC inhibitor, and by expressing a dominant-negative isoform of Ca2+-dependent PKC (apl-I). Thus, both PKA and PKC were necessary for operant conditioning. Injection of cAMP into B51 mimicked the effects of operant conditioning. Activation …


Spatiotemporally Distributed Frontotemporal Networks For Sentence Reading, Sidney R. Lehky, Xinmiao Peng, Carrie J. Mcadams, Anne B. Sereno Sep 2008

Spatiotemporally Distributed Frontotemporal Networks For Sentence Reading, Sidney R. Lehky, Xinmiao Peng, Carrie J. Mcadams, Anne B. Sereno

Faculty, Staff and Student Publications

BACKGROUND: A key aspect of representations for object recognition and scene analysis in the ventral visual stream is the spatial frame of reference, be it a viewer-centered, object-centered, or scene-based coordinate system. Coordinate transforms from retinocentric space to other reference frames involve combining neural visual responses with extraretinal postural information.

METHODOLOGY/PRINCIPAL FINDINGS: We examined whether such spatial information is available to anterior inferotemporal (AIT) neurons in the macaque monkey by measuring the effect of eye position on responses to a set of simple 2D shapes. We report, for the first time, a significant eye position effect in over 40% of …


A Functional Collagen Adhesin Gene, Acm, In Clinical Isolates Of Enterococcus Faecium Correlates With The Recent Success Of This Emerging Nosocomial Pathogen, Sreedhar R Nallapareddy, Kavindra V Singh, Pablo C Okhuysen, Barbara E Murray Sep 2008

A Functional Collagen Adhesin Gene, Acm, In Clinical Isolates Of Enterococcus Faecium Correlates With The Recent Success Of This Emerging Nosocomial Pathogen, Sreedhar R Nallapareddy, Kavindra V Singh, Pablo C Okhuysen, Barbara E Murray

Faculty, Staff and Student Publications

Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P


Contribution Of The Collagen Adhesin Acm To Pathogenesis Of Enterococcus Faecium In Experimental Endocarditis, Sreedhar R Nallapareddy, Kavindra V Singh, Barbara E Murray Sep 2008

Contribution Of The Collagen Adhesin Acm To Pathogenesis Of Enterococcus Faecium In Experimental Endocarditis, Sreedhar R Nallapareddy, Kavindra V Singh, Barbara E Murray

Faculty, Staff and Student Publications

Enterococcus faecium is a multidrug-resistant opportunist causing difficult-to-treat nosocomial infections, including endocarditis, but there are no reports experimentally demonstrating E. faecium virulence determinants. Our previous studies showed that some clinical E. faecium isolates produce a cell wall-anchored collagen adhesin, Acm, and that an isogenic acm deletion mutant of the endocarditis-derived strain TX0082 lost collagen adherence. In this study, we show with a rat endocarditis model that TX0082 Deltaacm::cat is highly attenuated versus wild-type TX0082, both in established (72 h) vegetations (P < 0.0001) and for valve colonization 1 and 3 hours after infection (P or=50-fold reduction relative to an Acm producer) were found in three of these five nonadherent isolates, including the sequenced strain TX0016, by quantitative reverse transcription-PCR, indicating that acm transcription is downregulated in vitro in these isolates. However, examination of TX0016 cells obtained directly from infected rat vegetations by flow cytometry showed that Acm was present on 40% of cells grown during infection. Finally, we demonstrated a significant reduction in E. faecium collagen adherence by affinity-purified anti-Acm antibodies from E. faecium endocarditis patient sera, suggesting that Acm may be a potential immunotarget for strategies to control this emerging pathogen.


An Sp1/Sp3 Binding Polymorphism Confers Methylation Protection, Yanis A. Boumber, Yutaka Kondo, Xuqi Chen, Lanlan Shen, Yi Guo, Carmen Tellez, Marcos R H Estécio, Saira Ahmed, Jean-Pierre J. Issa Aug 2008

An Sp1/Sp3 Binding Polymorphism Confers Methylation Protection, Yanis A. Boumber, Yutaka Kondo, Xuqi Chen, Lanlan Shen, Yi Guo, Carmen Tellez, Marcos R H Estécio, Saira Ahmed, Jean-Pierre J. Issa

Faculty, Staff and Student Publications

Hundreds of genes show aberrant DNA hypermethylation in cancer, yet little is known about the causes of this hypermethylation. We identified RIL as a frequent methylation target in cancer. In search for factors that influence RIL hypermethylation, we found a 12-bp polymorphic sequence around its transcription start site that creates a long allele. Pyrosequencing of homozygous tumors revealed a 2.1-fold higher methylation for the short alleles (P<0.001). Bisulfite sequencing of cancers heterozygous for RIL showed that the short alleles are 3.1-fold more methylated than the long (P<0.001). The comparison of expression levels between unmethylated long and short EBV-transformed cell lines showed no difference in expression in vivo. Electrophorectic mobility shift assay showed that the inserted region of the long allele binds Sp1 and Sp3 transcription factors, a binding that is absent in the short allele. Transient transfection of RIL allele-specific transgenes showed no effects of the additional Sp1 site on transcription early on. However, stable transfection of methylation-seeded constructs showed gradually decreasing transcription levels from the short allele with eventual spreading of de novo methylation. In contrast, the long allele showed stable levels of expression over time as measured by luciferase and approximately 2-3-fold lower levels of methylation by bisulfite sequencing (P<0.001), suggesting that the polymorphic Sp1 site protects against time-dependent silencing. Our finding demonstrates that, in some genes, hypermethylation in cancer is dictated by protein-DNA interactions at the promoters and provides a novel mechanism by which genetic polymorphisms can influence an epigenetic state.


Structures And Functions Of The Normal And Injured Human Olfactory Epithelium, Jonathan P Schuermann, Jianwen Jiang, Jorge Cuellar, Oscar Llorca, Liping Wang, Luis E Gimenez, Suping Jin, Alexander B Taylor, Borries Demeler, Kevin A Morano, P John Hart, Jose M Valpuesta, Eileen M Lafer, Rui Sousa Jul 2008

Structures And Functions Of The Normal And Injured Human Olfactory Epithelium, Jonathan P Schuermann, Jianwen Jiang, Jorge Cuellar, Oscar Llorca, Liping Wang, Luis E Gimenez, Suping Jin, Alexander B Taylor, Borries Demeler, Kevin A Morano, P John Hart, Jose M Valpuesta, Eileen M Lafer, Rui Sousa

Faculty, Staff and Student Publications

Hsp70s mediate protein folding, translocation, and macromolecular complex remodeling reactions. Their activities are regulated by proteins that exchange ADP for ATP from the nucleotide-binding domain (NBD) of the Hsp70. These nucleotide exchange factors (NEFs) include the Hsp110s, which are themselves members of the Hsp70 family. We report the structure of an Hsp110:Hsc70 nucleotide exchange complex. The complex is characterized by extensive protein:protein interactions and symmetric bridging interactions between the nucleotides bound in each partner protein's NBD. An electropositive pore allows nucleotides to enter and exit the complex. The role of nucleotides in complex formation and dissociation, and the effects of …


Brain Fiber Tract Plasticity In Experimental Spinal Cord Injury: Diffusion Tensor Imaging, Jaivijay Ramu, Juan Herrera, Raymond Grill, Tobias Bockhorst, Ponnada Narayana Jul 2008

Brain Fiber Tract Plasticity In Experimental Spinal Cord Injury: Diffusion Tensor Imaging, Jaivijay Ramu, Juan Herrera, Raymond Grill, Tobias Bockhorst, Ponnada Narayana

Faculty, Staff and Student Publications

Diffusion tensor imaging (DTI) and immunohistochemistry were performed in spinal cord injured rats to understand the basis for activation of multiple regions in the brain observed in functional magnetic resonance imaging (fMRI) studies. The measured fractional anisotropy (FA), a scalar measure of diffusion anisotropy, along the region encompassing corticospinal tracts (CST) indicates significant differences between control and injured groups in the 3 to 4 mm area posterior to bregma that correspond to internal capsule and cerebral peduncle. Additionally, DTI-based tractography in injured animals showed increased number of fibers that extend towards the cortex terminating in the regions that were activated …


The Temporal Relationship Between The Coronavirus Disease 2019 (Covid-19) Pandemic And Preterm Birth, Harold E Bedell, Mahalakshmi Ramamurthy, Saumil S Patel, Shobana Subramaniam, Lan-Phuong Vu-Yu, Jianliang Tong Jul 2008

The Temporal Relationship Between The Coronavirus Disease 2019 (Covid-19) Pandemic And Preterm Birth, Harold E Bedell, Mahalakshmi Ramamurthy, Saumil S Patel, Shobana Subramaniam, Lan-Phuong Vu-Yu, Jianliang Tong

Faculty, Staff and Student Publications

Despite rapid to-and-fro motion of the retinal image that results from their incessant involuntary eye movements, persons with infantile nystagmus (IN) rarely report the perception of motion smear. We performed two experiments to determine if the reduction of perceived motion smear in persons with IN is associated with an increase in the speed of the temporal impulse response. In Experiment 1, increment thresholds were determined for pairs of successively presented flashes of a long horizontal line, presented on a 65-cd/m2 background field. The stimulus-onset asynchrony (SOA) between the first and second flash varied from 5.9 to 234 ms. In experiment …


Water-Soluble Fullerene (C60) Derivatives As Nonviral Gene-Delivery Vectors, Balaji Sitharaman, Tatiana Y Zakharian, Anita Saraf, Preeti Misra, Jared Ashcroft, Su Pan, Quynh P Pham, Antonios G Mikos, Lon J Wilson, David A Engler Jul 2008

Water-Soluble Fullerene (C60) Derivatives As Nonviral Gene-Delivery Vectors, Balaji Sitharaman, Tatiana Y Zakharian, Anita Saraf, Preeti Misra, Jared Ashcroft, Su Pan, Quynh P Pham, Antonios G Mikos, Lon J Wilson, David A Engler

Faculty, Staff and Student Publications

A new class of water-soluble C60 transfecting agents has been prepared using Hirsch-Bingel chemistry and assessed for their ability to act as gene-delivery vectors in vitro. In an effort to elucidate the relationship between the hydrophobicity of the fullerene core, the hydrophilicity of the water-solubilizing groups, and the overall charge state of the C60 vectors in gene delivery and expression, several different C60 derivatives were synthesized to yield either positively charged, negatively charged, or neutral chemical functionalities under physiological conditions. These fullerene derivatives were then tested for their ability to transfect cells grown in culture with DNA carrying the green …


Synaptotagmin-2 Controls Regulated Exocytosis But Not Other Secretory Responses Of Mast Cells*, Qun-Fang Wan, Alejandro Vila, Zhen-Yu Zhou, Ruth Heidelberger Jul 2008

Synaptotagmin-2 Controls Regulated Exocytosis But Not Other Secretory Responses Of Mast Cells*, Qun-Fang Wan, Alejandro Vila, Zhen-Yu Zhou, Ruth Heidelberger

Faculty, Staff and Student Publications

To better understand synaptic signaling at the mammalian rod bipolar cell terminal and pave the way for applying genetic approaches to the study of visual information processing in the mammalian retina, synaptic vesicle dynamics and intraterminal calcium were monitored in terminals of acutely isolated mouse rod bipolar cells and the number of ribbon-style active zones quantified. We identified a releasable pool, corresponding to a maximum of 7 s. The presence of a smaller, rapidly releasing pool and a small, fast component of refilling was also suggested. Following calcium channel closure, membrane surface area was restored to baseline with a time …


Obesity And Cardiac Metabolism In Women, Heinrich Taegtmeyer, Mohamed F Algahim Jul 2008

Obesity And Cardiac Metabolism In Women, Heinrich Taegtmeyer, Mohamed F Algahim

Faculty, Staff and Student Publications

No abstract provided.