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Theses/Dissertations

2013

Medical Biochemistry

Articles 1 - 14 of 14

Full-Text Articles in Medical Sciences

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang Dec 2013

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang

Master's Theses

Quorum sensing (QS) is a process of coordination of bacterial gene expression in response to cell population. System two QS is regulated by the small signaling molecule autoinducer-2 (AI-2) and is implicated in the infectious behaviors of various bacterial species. AI-2 is biosynthesized from S-ribosylhomocysteine (SRH) by the enzyme LuxS and induces interspecies cell-to-cell communication. Inhibition of LuxS would therefore inhibit interspecies QS. Herein, a search for novel molecular species that will competitively bind with SRH in the LuxS binding site is performed in silico. Computational screening results are then validated in vitro using an optimized LuxS inhibition …

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Expression And Function Of Ca2+-Activated K+ Channels In Uterine Arteries, Ronghui Zhu Dec 2013

Expression And Function Of Ca2+-Activated K+ Channels In Uterine Arteries, Ronghui Zhu

Loma Linda University Electronic Theses, Dissertations & Projects

Chronic hypoxia during pregnancy is one of the most common insults to the maternal cardiovascular system and fetal development, and is associated with increased uterine vascular tone and heightened risk of preeclampsia and fetal intrauterine growth restriction (IUGR). The present study tested the hypothesis that calcium-activated potassium (KCa) channels play an essential role in uterine vascular adaptation to pregnancy, which is inhibited by chronic hypoxia during gestation. Uterine arteries (UAs) were isolated from nonpregnant ewes (NPUAs) and near-term pregnant ewes (PUAs) that had been maintained at sea level (~300 m) or exposed to high altitude (3,801 m) for 110 days. …

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A Novel Mechanism Of Enhanced Susceptibility To Bacterial Pneumonia In Influenza-Infected Hosts, Hazem Elsayed Ghoneim Dec 2013

A Novel Mechanism Of Enhanced Susceptibility To Bacterial Pneumonia In Influenza-Infected Hosts, Hazem Elsayed Ghoneim

Theses and Dissertations (ETD)

Viruses such as influenza suppress host immune function by a variety of methods. This may result in a significant morbidity through several pathways, including facilitation of secondary bacterial pneumonia from pathogens such as Streptococcus pneumoniae. Lungresident alveolar macrophages (AMs) act as the first line of innate cellular immunity against respiratory bacterial pathogens, including pneumococcus. Therefore, they represent an attractive target for study Before investigating the impact of influenza infection on resident AMs, we first characterized different subsets of lung-resident macrophages in naïve mice using a novel in vivo labeling approach in conjunction with multicolor flow cytometric analysis and confocal microscopic …

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Characterization Of The Functional Role And Therapeutic Potential Of Microrna Mir-125a In Acute Myeloid Leukemia, Melanie Lorraine Ufkin Dec 2013

Characterization Of The Functional Role And Therapeutic Potential Of Microrna Mir-125a In Acute Myeloid Leukemia, Melanie Lorraine Ufkin

Electronic Theses and Dissertations

Acute myeloid leukemia (AML) is a heterogeneous disease marked by a highly variable clinical course and response to therapy. The average age of individuals diagnosed with AML is approximately 69 years old. Due to age of the patient and how quickly the disease progresses, many are unable to receive therapy, leading to death between 4 and 12 weeks after diagnosis. More effective and less cytotoxic treatments are crucial for those diagnosed with AML. Therefore my work has been focused on understanding genetic pathways altered within AML to develop new-targeted therapies. Specifically, I have been studying microRNAs (miR), which regulate proteins …

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Macromolecular Complexes Of Cystic Fibrosis Transmembrane Conductance Regulator Alter Fluid Transport In Inflammatory Bowel Disorders, Kavisha Arora Aug 2013

Macromolecular Complexes Of Cystic Fibrosis Transmembrane Conductance Regulator Alter Fluid Transport In Inflammatory Bowel Disorders, Kavisha Arora

Theses and Dissertations (ETD)

Macromolecular complexes of cystic fibrosis transmembrane conductance regulator (CFTR) comprise of network of proteins that can regulate cAMP-/cGMP-activated CFTR chloride channel function. We report the physical and functional coupling of CFTR with nitric oxide (NO) producing enzyme-inducible nitric oxide synthase (iNOS) at the apical plasma membrane in inflammatory bowel disease (IBD). The complex formation requires the scaffolding protein Na+ /H+ exchanger regulatory factor 2 (NHERF2). We demonstrate that iNOS is overexpressed at or near the apical plasma membrane of gut epithelial cells in IBD and, through the stimulation of the NO-cGMP pathway, generates compartmentalized cGMP underneath the plasma membrane. This …

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Bioengineering The Expression Of Active Recombinant Human Cathepsin G, Enteropeptidase, Neutrophil Elastase, And C-Reactive Protein In Yeast, Eliot T. Smith Aug 2013

Bioengineering The Expression Of Active Recombinant Human Cathepsin G, Enteropeptidase, Neutrophil Elastase, And C-Reactive Protein In Yeast, Eliot T. Smith

Electronic Theses and Dissertations

The yeasts Pichia pastoris and Kluyveromyces lactis were used to express several recombinant human proteins for further biochemical characterization. Two substitution variants of recombinant human enteropeptidase light chain (rhEPL) were engineered to modify the extended substrate specificity of this serine protease. Both were secreted as active enzymes in excess of 1.7 mg/L in P. pastoris fermentation broth. The substitution variant rhEPL R96Q showed significantly reduced specificities for the preferred substrate sequences DDDDK and DDDDR; however, the rhEPL Y174R variant displayed improved specificities for these substrate sequences relative to all other reported variants of this enzyme. The neutrophil serine proteases human …

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Identification Of The Salivary Proteome In Children Throughout The Course Of Dental Eruption, Nada Tabbara Jul 2013

Identification Of The Salivary Proteome In Children Throughout The Course Of Dental Eruption, Nada Tabbara

Electronic Thesis and Dissertation Repository

The salivary proteome is recognized as a valuable source of potential oral and systemic disease biomarkers. Major efforts in salivary research have been dedicated to identify and characterize salivary proteins present in saliva using both classical biochemical methods and proteomics approaches in adults. Despite considerable research on the salivary proteome, little attention has been given to the changes in the salivary proteome occurring in children, specifically from 0-3 years of age. Through the use of anionic PAGE, SDS PAGE, HPLC and MS/MS, salivary protein profiles in children before, during and after dental eruption were compared with edentulous adult controls. We …

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Effect Of Procedural Pain On Purines, Mda And Allantoin In Premature Infants, Megan Sue Holden Jun 2013

Effect Of Procedural Pain On Purines, Mda And Allantoin In Premature Infants, Megan Sue Holden

Loma Linda University Electronic Theses, Dissertations & Projects

Identifying and measuring the biochemical effects of procedural pain in infants is a continuing challenge for clinicians. To address this issue we evaluated the relationship between procedural pain, ATP utilization (hypoxanthine and uric acid), and oxidative stress (MDA and allantoin) in premature infants. Through these studies we found that 1) a single heel-lance significantly increases plasma uric acid in rabbit kits, 2) tape removal increases MDA and prevents a decrease in uric acid in the plasma of premature infants, and 3) a single dose of oral sucrose before a heel-lance is sufficient to significantly increase plasma markers of ATP utilization …

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Role Of Igf-Ii, Prl, And Fabps In The Breast Cancer Disparity Among Aa Women, Teleka Cassandra Patrick Jun 2013

Role Of Igf-Ii, Prl, And Fabps In The Breast Cancer Disparity Among Aa Women, Teleka Cassandra Patrick

Loma Linda University Electronic Theses, Dissertations & Projects

It is well documented that African-American (AA) patients present with more advanced states of breast cancer and have lower survival rates than Caucasian-Americans (CA). Epidemiological data have shown that pregnancy and lactation at an early age in humans reduce the risk of breast cancer. Studies in mice and rats have shown that lactation stimulates the expression of intracellular fatty-acid binding protein 3 (FABP3). FABP3 is detected in human breast tissue and is known as mammary-derived growth inhibitor (MDGI) because it has a strong inhibitory effect on cell proliferation. FABP5 is also expressed in the breast, and has been associated with …

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Associations Between Alcohol Consumption And Fasting Blood Glucose In Young Adults, Julie Ann Lucca Jun 2013

Associations Between Alcohol Consumption And Fasting Blood Glucose In Young Adults, Julie Ann Lucca

Master's Theses

Current research shows moderate alcohol consumption is associated with decreased risk of diabetes and excessive consumption or binge drinking can cause insulin resistance and diabetes. In 2010, diabetes was the seventh leading cause of death in the United Statesand was responsible for significant health complications: blindness, kidney failure, and limb amputations, and is a large national economic burden. Fasting blood glucose (FBG) is a tool used to help diagnose diabetes. Abnormally high FBG, ≥100 mg/dl, is indicative of diabetes and pre-diabetes. Few studies have observed diabetic prevalence among young adults or college students. Studying young adults can help provide added …

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Study Of The Insulin Mimetic Sodium Orthovanadate In Glucosamine Induced Insulin Resistnace In Primary Rat Hepatocytes, Kalan Mcpherson Apr 2013

Study Of The Insulin Mimetic Sodium Orthovanadate In Glucosamine Induced Insulin Resistnace In Primary Rat Hepatocytes, Kalan Mcpherson

Masters Theses

Insulin resistance and type II diabetes is a disease state characterized by a lack of sensitivity of insulin to provoke a proper response in insulin sensitive tissues. Currently, we utilize glucosamine to increase flux through the Hexosamine Biosynthetic Pathway (HBP) to induce an insulin resistance like state in primary rat hepatocytes. We tested the effectiveness of the insulin mimetic sodium orthovanadate to determine if it could elicit an insulin-like response under these conditions. Mixed results were obtained on the effectiveness of vanadate as an insulin mimetic in this insulin resistant model.

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Heterogeneity In Platelet Exocytosis, Deepa Jonnalagadda Jan 2013

Heterogeneity In Platelet Exocytosis, Deepa Jonnalagadda

Theses and Dissertations--Molecular and Cellular Biochemistry

Platelet exocytosis is essential for hemostasis and for many of its sequelae. Platelets release numerous bioactive molecules stored in their granules enabling them to exert a wide range of effects on the vascular microenvironment. Are these granule cargo released thematically in a context-specific pattern or via a stochastic, kinetically-controlled process? My work describes platelet exocytosis using a systematic examination of platelet secretion kinetics. Platelets were stimulated for increasing times with different agonists (i.e. thrombin, PAR1-agonist, PAR4-agonist, and convulxin) and micro-ELISA arrays were used to quantify the release of 28 distinct α-granule cargo molecules. Agonist potency directly correlated with the speed …

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Biomarkers Of Disease : Concentrations In The Serum Of Women During Natural And Stimulated Ovarian Cycles And During Early Pregnancy, Melissa Stemp Jan 2013

Biomarkers Of Disease : Concentrations In The Serum Of Women During Natural And Stimulated Ovarian Cycles And During Early Pregnancy, Melissa Stemp

Theses: Doctorates and Masters

Molecular biomarkers are chemical signatures that all cell types possess. They are used in medicine to evaluate both normal biological events and pathogenic processes. A series of biomarkers associated with cancer of the breast, ovaries and other parts of the female reproductive tract and the monitoring of pregnancy were measured in disease‐free women. The biomarkers measured were prostate specific antigen (PSA), CA125, CA15‐3, CA72‐4, and pregnancy associated plasma protein‐a (PAPP‐A). The patterns of change during natural and stimulated ovarian cycles and early pregnancy were investigated to determine if these biomarkers could reflect normal events relating to ovulation and implantation/placentation. In …

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Amalgamation Of Nucleosides And Amino Acids In Antibiotic Biosynthesis, Sandra H. Barnard Jan 2013

Amalgamation Of Nucleosides And Amino Acids In Antibiotic Biosynthesis, Sandra H. Barnard

Theses and Dissertations--Pharmacy

The rapid increase in antibiotic resistance demands the identification of novel antibiotics with novel targets. One potential antibacterial target is the biosynthesis of peptidoglycan cell wall, which is both ubiquitous and necessary for bacterial survival. Both the caprazamycin-related compounds A-90289 and muraminomicin, as well as the capuramycin-related compounds A-503083 and A-102395 are potent inhibitors of the translocase I enzyme, one of the key enzymes required for cell wall biosynthesis. The caprazamycin-related compounds contain a core nonproteinogen b-hydroxy-a-amino acid referred to as 5’-C-glycyluridine (GlyU). Residing within the biosynthetic gene clusters of the aforementioned compounds is a shared open reading …

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