Medicine and Health Sciences Commons^™

Impaired Fast-Spiking, Suppressed Cortical Inhibition, And Increased Susceptibility To Seizures In Mice Lacking Kv3.2 K+ Channel Proteins, David Lau, Eleazar Vega-Saenz De Miera, Diego Contreras, Alan Chow, Richard Paylor, Christopher S. Leonard, Bernardo Rudy

NYMC Faculty Publications

Voltage-gated K(+) channels of the Kv3 subfamily have unusual electrophysiological properties, including activation at very depolarized voltages (positive to -10 mV) and very fast deactivation rates, suggesting special roles in neuronal excitability. In the brain, Kv3 channels are prominently expressed in select neuronal populations, which include fast-spiking (FS) GABAergic interneurons of the neocortex, hippocampus, and caudate, as well as other high-frequency firing neurons. Although evidence points to a key role in high-frequency firing, a definitive understanding of the function of these channels has been hampered by a lack of selective pharmacological tools. We therefore generated mouse lines in which one …

Ryanodine Receptor Adaptation, Michael Fill, A. Zahradníková, Carlos A. Villalba-Galea, I. Zahradník, A. L. Escobar, S. Györke

School of Pharmacy Faculty Articles

In the heart, depolarization during the action potential activates voltage-dependent Ca²⁺ channels that mediate a small, localized Ca²⁺ influx (I_Ca). This small Ca²⁺ signal activates specialized Ca²⁺ release channels, the ryanodine receptors (RyRs), in the sarcoplasmic reticulum (SR). This process is called Ca²⁺-induced Ca²⁺ release (CICR). Intuitively, the CICR process should be self-regenerating because the Ca²⁺ released from the SR should feedback and activate further SR Ca²⁺ release. However, the CICR process is precisely controlled in the heart and, consequently, some sort of negative control mechanism(s) must exist to …

Microbial Biofilms: From Ecology To Molecular Genetics, Mary Ellen Davey, George A. O'Toole

Dartmouth Scholarship

Biofilms are complex communities of microorganisms attached to surfaces or associated with interfaces. Despite the focus of modern microbiology research on pure culture, planktonic (free-swimming) bacteria, it is now widely recognized that most bacteria found in natural, clinical, and industrial settings persist in association with surfaces. Furthermore, these microbial communities are often composed of multiple species that interact with each other and their environment. The determination of biofilm architecture, particularly the spatial arrangement of microcolonies (clusters of cells) relative to one another, has profound implications for the function of these complex communities. Numerous new experimental approaches and methodologies have been …

Vaccinia Virus-Mediated Glioma Gene Therapy Using P53, Il-2 And Il-12, Bing Chen

Loma Linda University Electronic Theses, Dissertations & Projects

Malignant brain tumors are generally lethal soon after their diagnosis, and the five-year survival rate for the patient is low in spite of neurosurgery, radiation therapy, and/or chemotherapy. Gene therapy has the potential to improve patient survival and quality of life by delivering specific combinations of therapeutic genes directly to the tumor for localized treatment.

We have based our cancer gene therapy for glioma on a highly attenuated variant of the Lister strain of vaccinia virus (VV) which has been proven to be a safe and effective vaccine vector. Other advantages include a wide host range, a strong promoter system, …

Studies On The Purification And Role Of Igfbp-5 Protease In Bone, H. Garrett Rush Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

Osteoporosis is a disease characterized by low bone density and deterioration of mineralized bone leading to enhanced susceptibility to fracture. Several growth factors have been implicated in the coupling of formation to resorption during the bone remodeling process. The net bone forming activity of many growth factors has prompted numerous studies focused on the regulation of osteoblast cell proliferation, differentiation and activity. The current study focuses on the insulin-like growth factor (IGF) system, an important growth factor system involved in the regulation of bone formation and bone resorption.

IGF binding protein -5 (IGFBP-5), the most abundant IGF binding protein in …

Histological Pattern Of Ovarian Neoplasma., Zubair Ahmad, Naila Kayani, Sheema H. Hasan, Suhail Muzaffar, Muhammad Shafiq Gill

Department of Pathology and Laboratory Medicine

Abstract

Objective: To see the morphological pattern of benign and malignant ovarian neoplasms. Method: Retrospective study of all consecutive cases of ovarian neoplasms diagnosed at Aga Khan University Hospital between 1st January 1993 and 30th September 1998. Setting: The Section of Histopathology, AKUH, Karachi. Observation: Of 855 ovarian tumours 506 (59.18%) were benign and 349(40.81%) malignant. Surface epithelial - stromal tumours comprised 63.50% of all tumours. Benign cystic teratoma was the commonest benign tumour (35.17% of all benign tumours) and serous cystadenocarcinoma was the commonest malignant tumour (33.33% of all malignant tumours). Mucinous cystadenocarcinomas are more common in our population …

Arkansas Animal Science Department Report 2000, Zelpha B. Johnson, D. Wayne Kellogg

Arkansas Agricultural Experiment Station Research Series

Animal Science is very much devoted to youth education and development. During the past year, over 20,000 youth were involved in 4-H livestock projects. Two very successful activities that took place last year were the Mid-American Grassland Evaluation Contest and Livestock Judging Camps. The Grassland Contest is designed to teach students about grassland resource management for livestock and wildlife uses. The contest was held in Cape Girardeau, Missouri. Firstplace honors in the 4-H division went to White County, and second place honors went to Van Buren County. Two Livestock Judging Camps (Fayetteville and Hope) were conducted this past year. A …

Granular Cell Tumor Of The Breast: An Uncommon Lesion That Mimics Carcinoma, S Muzafar, M S. Siddiqui, Naila Kayani, I K. Lodhi, Sheema H. Hasan

Department of Pathology and Laboratory Medicine

No abstract provided.

Chronic Hypoxia, Exercise Training, And Skeletal Muscle Capillarity: Angiogenic Regulation And Morphological Consequences, Ivan Mark Olfert

Loma Linda University Electronic Theses, Dissertations & Projects

Angiogenesis is important in health and disease. In particular, exercise training is known to increase skeletal muscle capillarity, providing there is sufficient training intensity. The stimulus for this may be intracellular hypoxia activating angiogenic growth factor gene expression. Acute hypoxia alone has been shown to increase the gene expression of several key angiogenic regulators, e.g. vascular endothelial growth factor (VEGF) and to a lesser degree transforming growth factor-β1 (TGF-β1), basic fibroblast growth factor (bFGF), and thrombospondin-1 (TSP-1), an endogenous negative angiogenic regulator. Paradoxically, however, chronic hypoxia is generally not found to increase mammalian skeletal muscle capillarity. Accordingly, we hypothesized that …

Glucocorticoid Regulation Of Insulin Like Growth Factor Binding Protein-5 Gene Transcription In Human Osteoblasts, Xiaoying Wang

Loma Linda University Electronic Theses, Dissertations & Projects

Glucocorticoids (GCs) inhibit bone formation in vivo and inhibit osteoblast proliferation and collagen synthesis in vitro. These effects may be mediated by alterations in the insulin-like growth factor (IGF) system. In the present study of normal human osteoblast-like (HOB) cells, we tested the hypothesis that dexamethasone (Dex) inhibits the expression of IGF binding protein-5 (IGFBP-5). Dex decreased IGFBP-5 mRNA levels to 54% of control after 4 hr. Dex did not modify the decay of IGFBP-5 mRNA in transcriptionally arrested osteoblast cells. Dex decreased IGFBP-5 hnRNA levels to 67% of control after 2 hr, and the activity of the human IGFBP- …

Hybridization Of Dna By Sequential Immobilization Of Oligonucleotides At The Air-Water Interface, Murali Sastry, Vidya Ramakrishnan, Mrunalini Pattarkine, Anand Gole, K. N. Ganesh

Faculty Works

The hybridization of DNA by sequential electrostatic and hydrogen-bonding immobilization of single-stranded complementary oligonucleotides at the air-water interface with cationic Langmuir monolayers is demonstrated. The complexation of the single-stranded DNA molecules with octadecylamine (ODA) Langmuir monolayers was followed in time by monitoring the pressure-area isotherms. A large (and slow) expansion of the ODA monolayer was observed during each stage of complexation in the following sequence: primary single-stranded DNA followed by complementary single-stranded DNA followed by the intercalator, ethidium bromide. Langmuir-Blodgett (LB) films of the ODA-DNA complex were formed on different substrates and characterized using quartz-crystal microgravimetry (QCM), Fourier transform infrared …

Misattribution Of Sensory Input Reflected In Dysfunctional Target: Non-Target Erps In Schizophrenia, K. Brown, E. Gordon, L. Williams, H. Bahramali, A. Harris, J. Gray, C. J. Gonsalvez, R. Meares

Faculty of Health and Behavioural Sciences - Papers (Archive)

Background. While numerous studies have found disturbances in the Event-Related Potentials (ERPs) of patients with schizophrenia linked to task relevant target stimuli (most notably a reduction in P300 amplitude), few have examined ERPs to task irrelevant non-targets. We hypothesize, from current models of dysfunction in information processing in schizophrenia, that there will be less difference between ERPs to targets and non-targets in patients with schizophrenia than in controls.

Methods. EEGs were recorded for 40 subjects with schizophrenia and 40 age and sex matched controls during an auditory oddball reaction time task. ERPs to the targets and non-targets immediately preceding the …

Amino Acid Osmolytes In Regulatory Volume Decrease And Isovolumetric Regulation In Brain Cells: Contribution And Mechanisms, Herminia Pasantes-Morales, Rodrigo Franco, M. Eugenia Torres-Marquez, Karla Hernandez-Fonseca, Arturo Ortega

School of Veterinary and Biomedical Sciences: Faculty Publications

Brain adaptation to hyposmolarity is accomplished by loss of both electrolytes and organic osmolytes, including amino acids, polyalcohols and methylamines. In brain in vivo, the organic osmolytes account for about 35% of the total solute loss. This review focus on the role of amino acids in cell volume regulation, in conditions of sudden hyposmosis, when cells respond by active regulatory volume decrease (RVD) or after gradual exposure to hyposmotic solutions, a condition where cell volume remains unchanged, named isovolumetric regulation (IVR). The amino acid efflux pathway during RVD is passive and is similar in many respects to the volume-activated anion …

Method And Apparatus For Adaptive Filtering By Counting Acoustic Sample Zeroes In Ultrasound Imaging, Gregory R. Bashford, Edward D. Nonnweiler, David D. Becker, David John Muzilla

Biomedical Imaging and Biosignal Analysis Laboratory

An ultrasound imaging system having an adaptive spatial filter the filter coefficients of which, for particular image parameter sample, are determined by counting the number of neighboring image parameter samples having zero or near-zero values. If the number of zero or near-zero values in a data window is greater than a predetermined threshold, the data in the window is passed, not filtered. This filter has two advantages over other spatial filters. First, image parameter data samples having only zero or near-zero neighboring values (i.e., isolated "point noise") are not smeared. Second, boundaries such as the edge of color in a …

Dealing With A Dry Season, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Farmers' approaches to adverse seasonal conditions whether they be frost, flood or low rainfall should be to acquire as much information as possible on the immediate agronomic and financial situations and make a judgement on the longer term implications for the following seasons. Once the information has been acquired, in consultation with advisers, it is necessary to construct and implement agronomic and business strategies to deal with individual situations.

The agronomic and stocking options for the dry season supplied in this booklet deal with questions and issues arising from the Year 2000 season, which has been characterised by a mid …

Effects Of Calcium Β-Hmb Supplementation During Training On Markers Of Catabolism, Body Composition, Strength And Sprint Performance, Richard B. Kreider, Maria Pontes Ferreira, Michael Greenwood, M. Wilson, Pamela Grindstaff, Steven Plisk, Jeff Reinardy, Edward Cantler, Anthony L. Amalda

Nutrition and Food Science Faculty Research Publications

Calcium β-hydroxy β-methylbutyrate (HMB) supplementation has been reported to reduce catabolism and promote gains in strength and fat free mass in untrained individuals initiating training. However, the effects of HMB supplementation on strength and body composition alterations during training in athletes is less clear. This study examined the effects of 28-d of calcium HMB supplementation during intense training on markers of catabolism, body composition, strength, and sprint performance. In a double-blind and randomized manner, 28 NCAA division I-A football players were matched-paired and assigned to supplement their diet for 28-d during winter resistance/agility training (~8 hr/wk) with a carbohydrate placebo …

Santa Clara Magazine, Volume 42 Number 2, Fall 2000, Santa Clara University

Santa Clara Magazine

10 - I WANT MY IPO! By Susan Vogel. With so much venture capital available out there, why do women have to sprint to catch up with men in the race for funding?

14 - ON THE THRESHOLD OF A NEW ERA By George F. Giacomini, Jr. A long-time SCU professor offers his opinion of the most pivotal moments in the University's 150-year history, from wars to the admission of women.

18 - OF HEADHUNTERS AND SOLDIERS By Renato Rosaldo. Living with a headhunting Filipino tribe taught this author to be open to the possibility that other cultures have valid, …

The Toxicology Of Aluminum In The Brain: A Review, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Aluminum is environmentally ubiquitous, providing human exposure. Usual human exposure is primarily dietary. The potential for significant Al absorption from the nasal cavity and direct distribution into the brain should be further investigated. Decreased renal function increases human risk of Al-induced accumulation and toxicity. Brain Al entry from blood may involve transferrin-receptor mediated endocytosis and a more rapid process transporting small molecular weight Al species. There appears to be Al efflux from the brain, probably as Al citrate. There is prolonged retention of a fraction of Al that enters the brain, suggesting the potential for accumulation with repeated exposure. Al …

Induction Of Apoptosis In Human Prostate Cancer Cells By Resveratrol, Gary Zulfikar Morris

Chemistry & Biochemistry Theses & Dissertations

Recently attention has been brought to trans-resveratrol's {TR) anticancer activity, as determined through a number of cultured cancer cell models. This activity was attributed to TR behaving as an estrogen, and the orientation of TR' s hydroxyl groups. Based on this work it was of interest to determine whether TR would also be toxic in prostate cancer cells; if toxic, did TR induce necrosis or apoptosis in the cells; was it toxic through hormone mediated pathways; and were TR's hydroxyl groups responsible for its biological activity. To this end, cellular viability was assessed in two different prostate cancer cell …

Food Safety In The United States And The European Union: Sequel To A Case Study, Bryan Harris

RISK: Health, Safety & Environment (1990-2002)

The author reports on recent regulatory and legislative developments in the United States and European Union relating to toys imbedded in candy.

Connexin-32 Contributes To Radiation Resistance In Thyroid Follicles, Da-Thao Dinh Tran

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to examine the role of gap junctions in the radiation resistance of thyroid follicles. The question of whether gap junctional intercellular communication plays an important role in the “contact effect”, wherein cells in direct apposition are more resistant to the damaging effects of radiation, has been debated for years. We used the Fischer rat thyroid cell line (FRTL-5) to carry out our experiments. This thesis is divided into two parts: 1) characterization of gap junctional properties in FRTL-5 cells and, 2) exposure of these cells to radiation.

We found that, unlike primary thyroid cells, …

Genetic Diversity Of Beta-Thalassemia Mutations In Pakistani Population, B Khateeb, T Moatter, A M. Shaghil, S Haroon, G N. Kakepoto

Department of Pathology and Laboratory Medicine

Background:
beta-thalassemia is one of the most common inherited single gene disorder in Pakistan. It is characterized by reduced or absent beta-globin gene expression resulting in abnormal maturation and survival of red blood cells. Due to high prevalence of this disease in the local population, it has become important for the health care providers to encourage people to utilize laboratory facilities for carrier and prenatal genetic testing.
Objective:
To study the frequency of beta-thalassemia mutations in Pakistani population.
Setting:
A tertiary care teaching hospital.
Methods:
Blood samples of 72 couples and chorionic villus (CV) biopsy specimen collected at the Aga …

Interactions Of Igf-Ii And Cathepsin D In Mcf-7 Breast Cancer Cells, Jesika S. Faridi

Loma Linda University Electronic Theses, Dissertations & Projects

A primary role of the IGF-II/M6P receptor is to target lysosomal enzymes from the golgi to the lysosomes. This receptor has distinct binding sites for IGF-II and M6P, however, reciprocal interactions between these ligands have been observed (Kiess et al. 1989, 1990). Since IGF-II modulates the routing of cathepsin D in MCF-7 cells by blocking the intracellular binding of cathepsin D to the IGF-II/M6P receptor (De León et al. 1996), we hypothesized that expressing a mutant form of IGF-II that does not bind the IGF-II/M6P receptor will not interfere with lysosomal enzyme trafficking.

In our present study, we report the …

Identification And Characterization Of The Cis-Acting Elements Around The Murine Cd4 Cnhancer, Xin Dong

Loma Linda University Electronic Theses, Dissertations & Projects

The cluster determinant 4 (CD4) molecule is a transmembrane glycoprotein. CD4 is essential for normal T helper cell function and plays an important role in T cell development and activation. CD4 is encoded by a single gene located on chromosome 6 in the mouse and chromosome 12 in the human. Both human and murine CD4 genes are divided into ten exons spanning more than 25 kb and have a large non-coding region in the first and third intron. CD4 gene expression is controlled primarily at the transcriptional level during T cell development and activation.

An enhancer has been identified approximately …

Characterization Of 50s Ribosomal Subunit Assembly Inhibition In Erythromycin Treated Escherichia Coli Cells., Jerry Edward Usary

Electronic Theses and Dissertations

Erythromycin has long been recognized for its ability to inhibit protein synthesis by interfering with mRNA translation on the bacterial ribosome. We have recently shown that erythromycin also inhibits the assembly of the 50S ribosomal subunit in growing bacterial cells. The nature of this assembly inhibition has been investigated using ³H-uridine pulse-chase labeling of control and erythromycin treated E. coli cells.

Subunit assembly was examined by sucrose gradient centrifugation of labeled cell lysates. Normal assembly kinetics of subunit assembly were observed in control cells at 37°C. Formation of the 30S subunit was completed by 7.5 minutes and assembly of …

Vibrio Cholerae H-Ns Silences Virulence Gene Expression At Multiple Steps In The Toxr Regulatory Cascade, Melinda B. Nye, James D. Pfau, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

H-NS is an abundant nucleoid-associated protein involved in the maintenance of chromosomal architecture in bacteria. H-NS also has a role in silencing the expression of a variety of environmentally regulated genes during growth under nonpermissive conditions. In this study we demonstrate a role for H-NS in the negative modulation of expression of several genes within the ToxR virulence regulon ofVibrio cholerae. Deletion of hns resulted in high, nearly constitutive levels of expression of the genes encoding cholera toxin, toxin-coregulated pilus, and the ToxT virulence gene regulatory protein. For the cholera toxin- and ToxT-encoding genes, elevated expression in an …

Regional Variation In Recruitment Of Hemlock Seedlings And Saplings In The Upper Great Lakes, Usa, Thomas P. Rooney, Ronald J. Mccormick, Stephen L. Solheim, Donald M. Waller

Biological Sciences Faculty Publications

Mature eastern hemlock–northern hardwood forest cover decreased drastically in the upper Midwest following European settlement and has yet to rebound substantially. Previous studies show that stands retaining substantial hemlock canopy coverage have low hemlock seedling and sapling densities. Results from various geographically restricted studies suggest several possible mechanisms that could cause low seedling or sapling density. We examined the relative importance of these proposed mechanisms in the Southern Superior Uplands Section of the Laurentian Forest Province. We surveyed 294- m2 plots in 100 hemlock stands in northern Wisconsin and western upper Michigan to assess how these proposed mechanisms affect the …

La Notion De Danger, Jean M. Kanellopoulos, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

Pendant de nombreuses années, les recherches en immunologie ont été centrées sur la réponse immunitaire adaptative, et la plupart des immunologistes considéraient que sa fonction principale était de faire la distinction entre soi et non soi. Plus récemment, plusieurs équipes ont proposé que la fonction principale du système immunitaire est en réalité d’éliminer les agents pathogènes. Or, c’est le système immunitaire inné, longtemps négligé, qui joue un rôle essentiel dans l’induction d’une réponse contre les microorganismes. Ce système réagit précocement aux infections, voire instantanément, puis il induit et oriente la réponse du système adaptatif. Plusieursthéories ont été élaborées pour expliquer …

Prolonged Cyclooxygenase-2 Induction In Neurons And Glia Following Traumatic Brain Injury In The Rat, K I Strauss, M F Barbe, R M Marshall Demarest, R Raghupathi, S Mehta, R K Narayan

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Cyclooxygenase-2 (COX2) is a primary inflammatory mediator that converts arachidonic acid into precursors of vasoactive prostaglandins, producing reactive oxygen species in the process. Under normal conditions COX2 is not detectable, except at low abundance in the brain. This study demonstrates a distinctive pattern of COX2 increases in the brain over time following traumatic brain injury (TBI). Quantitative lysate ribonuclease protection assays indicate acute and sustained increases in COX2 mRNA in two rat models of TBI. In the lateral fluid percussion model, COX2 mRNA is significantly elevated (>twofold, p < 0.05, Dunnett) at 1 day postinjury in the injured cortex and bilaterally in the hippocampus, compared to sham-injured controls. In the lateral cortical impact model (LCI), COX2 mRNA peaks around 6 h postinjury in the ipsilateral cerebral cortex (fivefold induction, p < 0.05, Dunnett) and in the ipsilateral and contralateral hippocampus (two- and six-fold induction, respectively, p < 0.05, Dunnett). Increases are sustained out to 3 days postinjury in the injured cortex in both models. Further analyses use the LCI model to evaluate COX2 induction. Immunoblot analyses confirm increased levels of COX2 protein in the cortex and hippocampus. Profound increases in COX2 protein are observed in the cortex at 1-3 days, that return to sham levels by 7 days postinjury (p < 0.05, Dunnett). The cellular pattern of COX2 induction following TBI has been characterized using immunohistochemistry. COX2-immunoreactivity (-ir) rises acutely (cell numbers and intensity) and remains elevated for several days following TBI. Increases in COX2-ir colocalize with neurons (MAP2-ir) and glia (GFAP-ir). Increases in COX2-ir are observed in cerebral cortex and hippocampus, ipsilateral and contralateral to injury as early as 2 h postinjury. Neurons in the ipsilateral parietal, perirhinal and piriform cortex become intensely COX2-ir from 2 h to at least 3 days postinjury. In agreement with the mRNA and immunoblot results, COX2-ir appears greatest in the contralateral hippocampus. Hippocampal COX2-ir progresses from the pyramidal cell layer of the CA1 and CA2 region at 2 h, to the CA3 pyramidal cells and dentate polymorphic and granule cell layers by 24 h postinjury. These increases are distinct from those observed following inflammatory challenge, and correspond to brain areas previously identified with the neurological and cognitive deficits associated with TBI. While COX2 induction following TBI may result in selective beneficial responses, chronic COX2 production may contribute to free radical mediated cellular damage, vascular dysfunction, and alterations in cellular metabolism. These may cause secondary injuries to the brain that promote neuropathology and worsen behavioral outcome.

Morphological, Molecular, And Biogeographical Variation Within The Imperiled Virginia Spiraea, Constance Anders

Masters Theses & Specialist Projects

Spiraea virginiana Britton is a rare federally listed rhizomatous shrub endemic to the southern Blue Ridge and Appalachian Plateau physiographic provinces. Populations of S. virginiana are found restricted to scoured sections of high gradient streams within the Ohio River drainage. Present evidence indicates the species is reproducing asexually, most probably through the deposition of rhizomes from upstream populations forming new downstream ramets. Phenotypic variation was examined through a morphometric evaluation of 25 leaf measurements and analyzed using Principal Components Analysis (PCA) and discriminant function analysis. Identity and structure at the molecular level as examined with Randomly Amplified Polymorphic DNA (RAPDs) …