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Dysregulated Hepatic Methionine Metabolism Drives Homocysteine Elevation In Diet-Induced Nonalcoholic Fatty Liver Disease, Tommy Pacana, Sophie Cazanave, Aurora Verdianelli, Vaishali Patel, Hae-Ki Min, Faridoddin Mirshahi, Eoin Quinlivan, Arun J. Sanyal

Internal Medicine Publications

Methionine metabolism plays a central role in methylation reactions, production of glutathione and methylarginines, and modulating homocysteine levels. The mechanisms by which these are affected in NAFLD are not fully understood. The aim is to perform a metabolomic, molecular and epigenetic analyses of hepatic methionine metabolism in diet-induced NAFLD. Female 129S1/SvlmJ;C57Bl/6J mice were fed a chow (n = 6) or high-fat high-cholesterol (HFHC) diet (n = 8) for 52 weeks. Metabolomic study, enzymatic expression and DNA methylation analyses were performed. HFHC diet led to weight gain, marked steatosis and extensive fibrosis. In the methionine cycle, hepatic methionine was depleted (30%, …

Epigenetic Modifications Of The Pgc-1Α Promoter During Exercise Induced Expression In Mice, Timothy L. Lochmann, Ravindar R. Thomas, James P. Bennett, Shirley M. Taylor

Massey Comprehensive Cancer Center Publications

The transcriptional coactivator, PGC-1α, is known for its role in mitochondrial biogenesis. Although originally thought to exist as a single protein isoform, recent studies have identified additional promoters which produce multiple mRNA transcripts. One of these promoters (promoter B), approximately 13.7kb upstream of the canonical PGC-1α promoter (promoter A), yields alternative transcripts present at levels much lower than the canonical PGC-1α mRNA transcript. In skeletal muscle, exercise resulted in a substantial, rapid increase of mRNA of these alternative PGC-1α transcripts. Although the β2-adrenergic receptor was identified as a signaling pathway that activates transcription from PGC-1α promoter B, it is not …

Dismira: Prioritization Of Disease Candidates In Mirna-Disease Associations Based On Maximum Weighted Matching Inference Model And Motif-Based Analysis, Joseph J. Nalluri, Bhanu K. Kamapantula, Debmalya Barh, Neha Jain, Antaripa Bhattacharya, Sintia Silva De Almeida, Rommel Thiago Juca Ramos, Artur Silva, Vasco Azevedo, Preetam Ghosh

Computer Science Publications

Background

MicroRNAs (miRNAs) have increasingly been found to regulate diseases at a significant level. The interaction of miRNA and diseases is a complex web of multilevel interactions, given the fact that a miRNA regulates upto 50 or more diseases and miRNAs/diseases work in clusters. The clear patterns of miRNA regulations in a disease are still elusive.

Methods

In this work, we approach the miRNA-disease interactions from a network scientific perspective and devise two approaches - maximum weighted matching model (a graph theoretical algorithm which provides the result by solving an optimization equation of selecting the most prominent set of diseases) …

Use Of A Green Familiar Faces Paradigm Improves P300-Speller Brain-Computer Interface Performance, Qi Li, Shuai Lu, Jian Li, Ou Bai

Computer Science Publications

Background

A recent study showed improved performance of the P300-speller when the flashing row or column was overlaid with translucent pictures of familiar faces (FF spelling paradigm). However, the performance of the P300-speller is not yet satisfactory due to its low classification accuracy and information transfer rate.

Objective

To investigate whether P300-speller performance is further improved when the chromatic property and the FF spelling paradigm are combined.

Methods

We proposed a new spelling paradigm in which the flashing row or column is overlaid with translucent green pictures of familiar faces (GFF spelling paradigm). We analyzed the ERP waveforms elicited by …

Transcriptional Network Growing Models Using Motif-Based Preferential Attachment, Ahmed F. Abdelzaher, Ahmad F. Al-Musawi, Preetam Ghosh, Michael L. Mayo, Edward J. Perkins

Computer Science Publications

Understanding relationships between architectural properties of gene-regulatory networks (GRNs) has been one of the major goals in systems biology and bioinformatics, as it can provide insights into, e.g., disease dynamics and drug development. Such GRNs are characterized by their scale-free degree distributions and existence of network motifs – i.e., small-node subgraphs that occur more abundantly in GRNs than expected from chance alone. Because these transcriptional modules represent “building blocks” of complex networks and exhibit a wide range of functional and dynamical properties, they may contribute to the remarkable robustness and dynamical stability associated with the whole of GRNs. Here, we …

Miregulome: A Knowledge-Base Of Mirna Regulomics And Analysis, Debmalya Barh, Bhanu Kamapantula, Neha Jain, Joseph Nalluri, Antaripa Bhattacharya, Lucky Juneja, Neha Barve, Sandeep Tiwari, Anderson Miyoshi, Vasco Azevedo, Kenneth Blum, Anil Kumar, Artur Silva, Preetam Ghosh

Computer Science Publications

miRNAs regulate post transcriptional gene expression by targeting multiple mRNAs and hence can modulate multiple signalling pathways, biological processes, and patho-physiologies. Therefore, understanding of miRNA regulatory networks is essential in order to modulate the functions of a miRNA. The focus of several existing databases is to provide information on specific aspects of miRNA regulation. However, an integrated resource on the miRNA regulome is currently not available to facilitate the exploration and understanding of miRNA regulomics. miRegulome attempts to bridge this gap. The current version of miRegulome v1.0 provides details on the entire regulatory modules of miRNAs altered in response to …

Self-Organizing Feature Maps Identify Proteins Critical To Learning In A Mouse Model Of Down Syndrome, Clara Higuera, Katheleen J. Gardiner, Krzysztof J. Cios

Computer Science Publications

Down syndrome (DS) is a chromosomal abnormality (trisomy of human chromosome 21) associated with intellectual disability and affecting approximately one in 1000 live births worldwide. The overexpression of genes encoded by the extra copy of a normal chromosome in DS is believed to be sufficient to perturb normal pathways and normal responses to stimulation, causing learning and memory deficits. In this work, we have designed a strategy based on the unsupervised clustering method, Self Organizing Maps (SOM), to identify biologically important differences in protein levels in mice exposed to context fear conditioning (CFC). We analyzed expression levels of 77 proteins …

Self-Organizing Feature Maps Identify Proteins Critical To Learning In A Mouse Model Of Down Syndrome, Clara Higuera, Katheleen J. Gardiner, Kryzysztof Cios

Computer Science Publications

Down syndrome (DS) is a chromosomal abnormality (trisomy of human chromosome 21) associated with intellectual disability and affecting approximately one in 1000 live births worldwide. The overexpression of genes encoded by the extra copy of a normal chromosome in DS is believed to be sufficient to perturb normal pathways and normal responses to stimulation, causing learning and memory deficits. In this work, we have designed a strategy based on the unsupervised clustering method, Self Organizing Maps (SOM), to identify biologically important differences in protein levels in mice exposed to context fear conditioning (CFC). We analyzed expression levels of 77 proteins …

Self-Organizing Feature Maps Identify Proteins Critical To Learning In A Mouse Model Of Down Syndrome, Clara Higuera, Kathleen J. Gardiner, Kryzysztof Cios

Computer Science Publications

Down syndrome (DS) is a chromosomal abnormality (trisomy of human chromosome 21) associated with intellectual disability and affecting approximately one in 1000 live births worldwide. The overexpression of genes encoded by the extra copy of a normal chromosome in DS is believed to be sufficient to perturb normal pathways and normal responses to stimulation, causing learning and memory deficits. In this work, we have designed a strategy based on the unsupervised clustering method, Self Organizing Maps (SOM), to identify biologically important differences in protein levels in mice exposed to context fear conditioning (CFC). We analyzed expression levels of 77 proteins …

Identifying Influential Nodes In A Wound Healing-Related Network Of Biological Processes Using Mean First-Passage Time, Tomasz Jakub Arodz, Danail Bonchev

Computer Science Publications

In this study we offer an approach to network physiology, which proceeds from transcriptomic data and uses gene ontology analysis to identify the biological processes most enriched in several critical time points of wound healing process (days 0, 3 and 7). The top-ranking differentially expressed genes for each process were used to build two networks: one with all proteins regulating the transcription of selected genes, and a second one involving the proteins from the signaling pathways that activate the transcription factors. The information from these networks is used to build a network of the most enriched processes with undirected links …

Vedolizumab: An Α4Β7 Integrin Antagonist For Ulcerative Colitis And Crohn’S Disease, Lauren N. Cherry, Nancy S. Yunker, Erika R. Lambert, Dalemarie Vaughan, Denise K. Lowe

VCU Health Publications

Ulcerative colitis (UC) and Crohn’s disease (CD) are chronic, relapsing inflammatory bowel diseases associated with significant morbidity. Conventional therapies for these diseases include corticosteroids, aminosalicylates, immunomodulators, and monoclonal antibodies. Over the years tumor necrosis factor (TNF)-α antagonists alone or in combination with other therapies have emerged as the cornerstone of treatment for induction and maintenance of remission of moderate to severe UC and CD. Unfortunately, some patients with moderate to severe UC and CD are unable to attain or maintain remission with TNF-α antagonist treatment. Vedolizumab, a humanized monoclonal antibody, is the first integrin receptor antagonist approved that selectively antagonizes …

Perceived Stress Levels, Chemotherapy, Radiation Treatment And Tumor Characteristics Are Associated With A Persistent Increased Frequency Of Somatic Chromosomal Instability In Women Diagnosed With Breast Cancer: A One Year Longitudinal Study, Noran Aboalela, Debra E. Lyon, R. K. Elswick Jr., Debra Lynch Kelly, Jenni Brumelle, Harry D. Bear, Colleen Jackson-Cook

VCU Health Publications

While advances in therapeutic approaches have resulted in improved survival rates for women diagnosed with breast cancer, subsets of these survivors develop persistent psychoneurological symptoms (fatigue, depression/anxiety, cognitive dysfunction) that compromise their quality of life. The biological basis for these persistent symptoms is unclear, but could reflect the acquisition of soma-wide chromosomal instability following the multiple biological/psychological exposures associated with the diagnosis/treatment of breast cancer. An essential first step toward testing this hypothesis is to determine if these cancer-related exposures are indeed associated with somatic chromosomal instability frequencies. Towards this end, we longitudinally studied 71 women (ages 23-71) with early-stage …

Using An In-Vitro Biofilm Model To Assess The Virulence Potential Of Bacterial Vaginosis Or Non-Bacterial Vaginosis Gardnerella Vaginalis Isolates, Joana Castro, Patricia Alves, Cármen Sousa, Tatiana Cereija, Ângela França, Kimberly K. Jefferson, Nuno Cerca

VCU Health Publications

Gardnerella vaginalis is the most common species found in bacterial vaginosis (BV). However, it is also present in a significant proportion of healthy women and G. vaginalis vaginal colonization does not always lead to BV. In an effort to better understand the differences between G. vaginalis isolated from women with a positive (BV) versus a negative (non-BV) diagnosis of BV, we compared the virulence potential of 7 BV and 7 non-BV G. vaginalis isolates and assessed the virulence factors related to biofilm formation, namely: initial adhesion and cytotoxic effect, biofilm accumulation, susceptibility to antibiotics, and transcript levels of the known …

Novel Zno Hollow-Nanocarriers Containing Paclitaxel Targeting Folate-Receptors In A Malignant Ph-Microenvironment For Effective Monitoring And Promoting Breast Tumor Regression, Nagaprasad Puvvada, Shashi Rajput, B. N. Prashanth Kumar, Siddik Sarkar, Suraj Konar, Keith R. Brunt, Raj R. Rao, Abhijit Mazumdar, Swadesh K. Das, Ranadhir Basu, Paul B. Fisher, Mahitosh Mandal, Amita Pathak

VCU Health Publications

Low pH in the tumor micromilieu is a recognized pathological feature of cancer. This attribute of cancerous cells has been targeted herein for the controlled release of chemotherapeutics at the tumour site, while sparing healthy tissues. To this end, pH-sensitive, hollow ZnO-nanocarriers loaded with paclitaxel were synthesized and their efficacy studied in breast cancer in vitro and in vivo. The nanocarriers were surface functionalized with folate using click-chemistry to improve targeted uptake by the malignant cells that over-express folate-receptors. The nanocarriers released ~75% of the paclitaxel payload within six hours in acidic pH, which was accompanied by switching of …

“I Am Not Free While [Anyone] Is Unfree”: A Proposal And Framework For Enmarginalized Feminist Policy Analysis, Avina Ross

Social Work Student Works

This paper introduces a new feminist approach and framework to policy analysis. As an integration of intersectionality, Black feminist thought and endarkened feminist epistemology, enmarginalized feminist policy analysis (EFPA) offers an intersectional and flexible scope in a framework to assess policy for a diversity of populations, focusing on groups who are forced to live marginal and oppressed lives. Discussion is provided on existing approaches and frameworks in addition to an overview of the theoretical underpinnings of EFPA. A nine-component framework, which includes a section for analyst reflexivity, is provided to guide users in conducting EFPA. The author concludes with implications …

Flow-Cytometry Machine For The Developing World, Paul Howell, Jewel Nkwocha, Jaynie Laverty

Capstone Design Expo Posters

Flow cytometry provides critical diagnostic, measurement, and research applications across many healthcare and biological disciplines. Its use in the detection of blood-cancers, HIV/AIDS, cell differentiation, and viral detection is unique and unparalleled. Despite flow cytometry’s vast array of applications, its use is limited by expense. Rather than individual labs being able to afford a dedicated machine, core facilities are developed and the research is exported. In addition, flow cytometry’s high costs create a barrier to its implementation in developing nations.

There were 35 million people living with HIV in 2013, nearly 1% of the world’s population. There are more than …

Pde5 Inhibitors Enhance Celecoxib Killing In Multiple Tumor Types, Laurence Booth, Jane L. Roberts, Nichola Cruickshanks, Seyedmehrad Tavallai, Timothy Webb, Peter Samuel, Adam Conley, Brittany Binion, Harold F. Young, Andrew Poklepovic, Sarah Spiegel, Paul Dent

Biochemistry and Molecular Biology Publications

The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 …

The Signal Transducer And Activator Of Transcription 1 (Stat1) Inhibits Mitochondrial Biogenesis In Liver And Fatty Acid Oxidation In Adipocytes, Jennifer D. Sisler, Magdalena Morgan, Vidisha Raje, Rebecca C. Grande, Marta Derecka, Jeremy Meier, Marc Cantwell, Karol Szczepanek, William J. Korzun, Edward J. Lesnefsky, Thurl E. Harris, Colleen M. Croniger, Andrew C. Larner

Biochemistry and Molecular Biology Publications

The transcription factor STAT1 plays a central role in orchestrating responses to various pathogens by activating the transcription of nuclear-encoded genes that mediate the antiviral, the antigrowth, and immune surveillance effects of interferons and other cytokines. In addition to regulating gene expression, we report that STAT1-/- mice display increased energy expenditure and paradoxically decreased release of triglycerides from white adipose tissue (WAT). Liver mitochondria from STAT1-/- mice show both defects in coupling of the electron transport chain (ETC) and increased numbers of mitochondria. Consistent with elevated numbers of mitochondria, STAT1-/- mice expressed increased amounts of PGC1α, a …

Generation Of Multicellular Tumor Spheroids With Microwell-Based Agarose Scaffolds For Drug Testing, Xue Gong, Chao Lin, Jian Cheng, Jiansheng Su, Hang Zhao, Tianlin Liu, Xuejun Wen, Peng Zhao

Chemical and Life Science Engineering Publications

Three dimensional multicellular aggregate, also referred to as cell spheroid or microtissue, is an indispensable tool for in vitro evaluating antitumor activity and drug efficacy. Compared with classical cellular monolayer, multicellular tumor spheroid (MCTS) offers a more rational platform to predict in vivo drug efficacy and toxicity. Nevertheless, traditional processing methods such as plastic dish culture with nonadhesive surfaces are regularly time-consuming, laborious and difficult to provide uniform-sized spheroids, thus causing poor reproducibility of experimental data and impeding high-throughput drug screening. In order to provide a robust and effective platform for in vitro drug evaluation, we present an agarose scaffold …

Perceived Stress Levels, Chemotherapy, Radiation Treatment And Tumor Characteristics Are Associated With A Persistent Increased Frequency Of Somatic Chromosomal Instability In Women Diagnosed With Breast Cancer: A One Year Longitudinal Study, Noran Aboalela, Debra E. Lyon, R. K. Elswick Jr., Debra Lynch Kelly, Jenni Brumelle, Harry D. Bear, Colleen Jackson-Cook

Human and Molecular Genetics Publications

While advances in therapeutic approaches have resulted in improved survival rates for women diagnosed with breast cancer, subsets of these survivors develop persistent psychoneurological symptoms (fatigue, depression/anxiety, cognitive dysfunction) that compromise their quality of life. The biological basis for these persistent symptoms is unclear, but could reflect the acquisition of soma-wide chromosomal instability following the multiple biological/psychological exposures associated with the diagnosis/treatment of breast cancer. An essential first step toward testing this hypothesis is to determine if these cancer-related exposures are indeed associated with somatic chromosomal instability frequencies. Towards this end, we longitudinally studied 71 women (ages 23-71) with early-stage …

Differential Expression Analysis Of Rna Sequencing Data By Incorporating Non-Exonic Mapped Reads, Hung-I Harry Chen, Yuanhang Liu, Yi Zou, Zhao Lai, Devanand Sarkar, Yufei Huang, Yidong Chen

Human and Molecular Genetics Publications

Background

RNA sequencing (RNA-seq) is a powerful tool for genome-wide expression profiling of biological samples with the advantage of high-throughput and high resolution. There are many existing algorithms nowadays for quantifying expression levels and detecting differential gene expression, but none of them takes the misaligned reads that are mapped to non-exonic regions into account. We developed a novel algorithm, XBSeq, where a statistical model was established based on the assumption that observed signals are the convolution of true expression signals and sequencing noises. The mapped reads in non-exonic regions are considered as sequencing noises, which follows a Poisson distribution. Given …

Depletion Of The Chromatin Remodeler Chd4 Sensitizes Aml Blasts To Genotoxic Agents And Reduces Tumor Formation, Justin Sperlazza, Mohamed Rahmani, Jason Beckta, Mandy Aust, Elisa Hawkins, Shou Zhen Wang, Sheng Zu Zhu, Shreya Podder, Catherine Dumur, Kellie Archer, Steven Grant, Gordon D. Ginder

Human and Molecular Genetics Publications

Chromodomain helicase DNA-binding protein 4 (CHD4) is an ATPase that alters the phasing of nucleosomes on DNA and has recently been implicated in DNA double-stranded break (DSB) repair. Here, we show that depletion of CHD4 in acute myeloid leukemia (AML) blasts induces a global relaxation of chromatin that renders cells more susceptible to DSB formation, while concurrently impeding their repair. Furthermore, CHD4 depletion renders AML blasts more sensitive both in vitro and in vivo to genotoxic agents used in clinical therapy: daunorubicin (DNR) and cytarabine (ara-C). Sensitization to DNR and ara-C is mediated in part by activation of the ataxia-telangiectasia …

Knockdown Of Cdk2ap1 In Primary Human Fibroblasts Induces P53 Dependent Senescence, Khaled N. Alsayegh, Venkat S. Gadepalli, Shilpa Iyer, Raj R. Rao

Human and Molecular Genetics Publications

Cyclin Dependent Kinase-2 Associated Protein-1 (CDK2AP1) is known to be a tumor suppressor that plays a role in cell cycle regulation by sequestering monomeric CDK2, and targeting it for proteolysis. A reduction of CDK2AP1 expression is considered to be a negative prognostic indicator in patients with oral squamous cell carcinoma and also associated with increased invasion in human gastric cancer tissue. CDK2AP1 overexpression was shown to inhibit growth, reduce invasion and increase apoptosis in prostate cancer cell lines. In this study, we investigated the effect of CDK2AP1 downregulation in primary human dermal fibroblasts. Using a short-hairpin RNA to reduce its …

Tumor-Specific Expression And Detection Of A Cest Reporter Gene, Il Minn, Amnon Bar-Shir, Keerthi Yarlagadda, Jeff W. M. Bulte, Paul B. Fisher, Hao Wang, Assaf A. Gilad, Martin G. Pomper

Human and Molecular Genetics Publications

Purpose

To develop an imaging tool that enables the detection of malignant tissue with enhanced specificity using the exquisite spatial resolution of MRI.

Methods

Two mammalian gene expression vectors were created for the expression of the lysine-rich protein (LRP) under the control of the cytomegalovirus (CMV) promoter and the progression elevated gene-3 promoter (PEG-3 promoter) for constitutive and tumor-specific expression of LRP, respectively. Using those vectors, stable cell lines of rat 9L glioma, 9LCMV-LRP and 9LPEG-LRP, were established and tested for CEST contrast in vitro and in vivo.

Results

9LPEG-LRP cells showed increased CEST contrast compared with 9L cells …

Tumor-Specific Expression And Detection Of A Cest Reporter Gene, Il Minn, Amnon Bar-Shir, Keerthi Yarlagadda, Jeff W. M. Bulte, Paul B. Fisher, Hao Wang, Assaf A. Gilad, Martin G. Pomper

Human and Molecular Genetics Publications

Purpose

To develop an imaging tool that enables the detection of malignant tissue with enhanced specificity using the exquisite spatial resolution of MRI.

Methods

Two mammalian gene expression vectors were created for the expression of the lysine-rich protein (LRP) under the control of the cytomegalovirus (CMV) promoter and the progression elevated gene-3 promoter (PEG-3 promoter) for constitutive and tumor-specific expression of LRP, respectively. Using those vectors, stable cell lines of rat 9L glioma, 9LCMV-LRP and 9LPEG-LRP, were established and tested for CEST contrast in vitro and in vivo.

Results

9LPEG-LRP cells showed increased CEST contrast compared with 9L cells …

Perceived Stress Levels, Chemotherapy, Radiation Treatment And Tumor Characteristics Are Associated With A Persistent Increased Frequency Of Somatic Chromosomal Instability In Women Diagnosed With Breast Cancer: A One Year Longitudinal Study, Noran Aboalela, Debra E. Lyon, R. K. Elswick Jr., Debra Lynch Kelly, Jenni Brumelle, Harry D. Bear, Colleen Jackson-Cook

Human and Molecular Genetics Publications

While advances in therapeutic approaches have resulted in improved survival rates for women diagnosed with breast cancer, subsets of these survivors develop persistent psychoneurological symptoms (fatigue, depression/anxiety, cognitive dysfunction) that compromise their quality of life. The biological basis for these persistent symptoms is unclear, but could reflect the acquisition of soma-wide chromosomal instability following the multiple biological/psychological exposures associated with the diagnosis/treatment of breast cancer. An essential first step toward testing this hypothesis is to determine if these cancer-related exposures are indeed associated with somatic chromosomal instability frequencies. Towards this end, we longitudinally studied 71 women (ages 23-71) with early-stage …

Knockdown Of Cdk2ap1 In Primary Human Fibroblasts Induces P53 Dependent Senescence, Khaled N. Alsayegh, Venkat S. Gadepalli, Shilpa Iyer, Raj R. Rao

Human and Molecular Genetics Publications

Cyclin Dependent Kinase-2 Associated Protein-1 (CDK2AP1) is known to be a tumor suppressor that plays a role in cell cycle regulation by sequestering monomeric CDK2, and targeting it for proteolysis. A reduction of CDK2AP1 expression is considered to be a negative prognostic indicator in patients with oral squamous cell carcinoma and also associated with increased invasion in human gastric cancer tissue. CDK2AP1 overexpression was shown to inhibit growth, reduce invasion and increase apoptosis in prostate cancer cell lines. In this study, we investigated the effect of CDK2AP1 downregulation in primary human dermal fibroblasts. Using a short-hairpin RNA to reduce its …

Comparison Of Effects Of P53 Null And Gain-Of-Function Mutations On Salivary Tumors In Mmtv-Hras Transgenic Mice, Dadi Jiang, Catherine I. Dumur, H. Davis Massey, Viswanathan Ramakrishnan, Mark A. Subler, Jolene J. Windle

Human and Molecular Genetics Publications

p53 is an important tumor suppressor gene which is mutated in ~50% of all human cancers. Some of these mutants appear to have acquired novel functions beyond merely losing wild-type functions. To investigate these gain-of-function effects in vivo, we generated mice of three different genotypes: MMTV-Hras/p53+/+, MMTV-Hras/p53-/-, and MMTV-Hras/p53R172H/R172H. Salivary tumors from these mice were characterized with regard to age of tumor onset, tumor growth rates, cell cycle distribution, apoptotic levels, tumor histopathology, as well as response to doxorubicin treatment. Microarray analysis was also performed to profile gene expression. The MMTV-Hras/p53-/- and …

Regulation Of Osteoblast Differentiation By Acid-Etched And/Or Grit-Blasted Titanium Substrate Topography Is Enhanced By 1,25(Oh)2d3 In A Sex-Dependent Manner, Rene Olivares-Navarrete, Sharon L. Hyzy, Barbara D. Boyan, Zvi Schwartz

Biomedical Engineering Publications

This study assessed contributions of micron-scale topography on clinically relevant titanium (Ti) to differentiation of osteoprogenitor cells and osteoblasts; the interaction of this effect with 1𝛼,25-dihydroxyvitamin D₃ (1𝛼,25(OH)₂D₃); and if the effects are sex-dependent. Male and female rat bone marrow cells (BMCs) were cultured on acid-etched (A, 𝑅_𝑎 = 0.87 𝜇m), grit-blasted (GB, 𝑅_𝑎 = 3.90 𝜇m), or grit-blasted/acid-etched (SLA, 𝑅_𝑎 = 3.22 𝜇m) Ti. BMCs were sensitive to surface topography and underwent osteoblast differentiation. This was greatest on SLA; acid etching and grit blasting contributed additively. Primary osteoblasts were also sensitive …

Frontal Cryosectioning: An Improved Protocol For Sectioning Large Areas Of Fibrous Scaffolds, Casey Grey, David G. Simpson

Biomedical Engineering Publications

Fibrous tissue engineering scaffolds, such as those produced by electrospinning, cannot achieve their clinical potential until deep cell-scaffold interactions are understood. Even the most advanced imaging techniques are limited to capturing data at depths of 100 µm due to light scatter associated with the fibers that compose these scaffolds. Conventional cross-sectional analysis provides information on relatively small volumes of space and frontal sections are difficult to generate. Current understanding of cellular penetration into fibrous scaffolds is limited predominantly to the scaffold surface. Although some information is available from cross-sections, sections vary in quality, can distort spatial scaffold properties, and offer …