Digital Commons Network^™

New Frontiers In The Reperfusion Of Myocardialinfarction, Mehmet Ağirbasli, Spencer B. King

Turkish Journal of Medical Sciences

No abstract provided.

Regeneration Of Hair Cell Epithelia In The Chick And Salamander, Kenneth Detwiler

Masters Theses & Specialist Projects

The acousticolateralis sensory system is characterized by a specific receptor cell type called the sensory hair cell and is found in all vertebrates. There are two types of hair cell sensory epithelia based on location: those of the inner ear, such as the organs for hearing and balance, and the lateral line system located within the epidermis. In mammals, including humans, loss or damage of the hair cells of the auditorysystem results in permanent hearing loss. However, this is not the case with birds and amphibians. Amphibians, with a lateral line system, are capable of replacing lost or damaged hair …

The Isolation And Partial Purification Of Dna Polymerase-Beta From Soybean, Lesa Dill

Masters Theses & Specialist Projects

5 kilodaltons). Its activation and inhibition spectra were similar to those previously determined for animal polymerase-beta. Therefore, since the structure of polymerase-beta shows significant evolutionary conservation in both plant and animal species and given strong functional correlations among species, polymerase-beta performs a vital role in plants in the repair of newly synthesized DNA just as it does in animal systems.

The Role Of Gap Junctions In Congenital Diseases Of The Heart, Scott Henry Britz-Cunningham

Loma Linda University Electronic Theses, Dissertations & Projects

Background. Gap junctions are thought to have a crucial role in the synchronized contraction of the heart and in embryonic development. Connexin43, the major protein of gap junctions in the heart, is targeted by several protein kinases that regulate myocardial cell-cell coupling. We hypothesized that mutations altering sites critical to this regulation would lead to functional or developmental abnormalities of the heart.

Methods. Connexin43 DNA from 25 normal subjects and 30 children with a variety of congenital heart diseases was amplified by the polymerase chain reaction and sequenced. Mutant DNA was expressed in cell culture and examined for its effect …

Staphylococcal Enterotoxin B Primes Cytokine Secretion And Lytic Activity In Response To Native Bacterial Antigens, K. M. Mason, T. D. Dryden, Nancy J. Bigley, P. S. Fink

Neuroscience, Cell Biology & Physiology Faculty Publications

Superantigens stimulate T-lymphocyte proliferation and cytokine production, but the effects of superantigen exposure on cell function within a complex, highly regulated immune response remain to be determined. In this study, we demonstrate that superantigen exposure significantly alters the murine host response to bacterial antigens in an in vitro coculture system. Two days after exposure to the superantigen staphylococcal enterotoxin B, splenocytes cultured with Streptococcus mutans produced significantly greater amounts of gamma interferon (IFN-gamma) and interleukin-12 than did sham-injected controls. The majority of IFN-gamma production appeared to be CD8(+) T-cell derived since depletion of this cell type dramatically reduced the levels …

Assessment Of Side Effects Induced By Injection Of Different Adjuvant/Antigen Combinations In Rabbits And Mice, P.P.A.M. Leenaars, M. A. Koedam, P. W. Wester, V. Baumans, E. Claassen, C. F.M. Hendriksen

Biomedicine and Animal Models in Research Collection

We evaluated the side effects induced by injection of Freund's adjuvant (FA)and alternative adjuvants combined with different antigens. Rabbits and mice were injected subcutaneously, intramuscularly (rabbits) and intraperitoneally (mice)with different adjuvants (FA, Specol, RIBI,TiterMax, Montanide ISA50)in combination with several types of antigens (synthetic peptides, autoantigen, glycolipid, protein, mycoplasma or viruses). The effects of treatment on the animals' well-being were assessed by clinical and behavioural changes (POTand LABORASassays) and gross and histopathological changes. In rabbits, treatment did not appear to induce acute or prolonged pain and distress. Mice showed behavioural changes immediately after (predominantly secondary) immunization. Injection of several adjuvant/antigen mixtures …

Animal Organs In Humans: Uncalculated Risks And Unanswered Questions, Gillian R. Langley, Joyce D'Silva

Biomedicine and Animal Models in Research Collection

This report, produced jointly by the British Union for the Abolition of Vivisection and Compassion in World Farming, fills a number of significant gaps in the current debate about xenotransplantation.

In this report we also summarise the ethical and welfare issues concerning experiments on animals for xenotransplant research and their possible use as source animals for organs. Both these aspects are responsible for much pain and distress caused to many animals. We prefer the term “source animals” to “donor animals”, because animals do not choose to donate their organs for xenotransplantation.

Influence Of Physical Setting On Seagrass Landscapes Near Beaufort, North Carolina, Usa, Mark S. Fonseca, Susan S. Bell

Integrative Biology Faculty and Staff Publications

Field surveys were conducted in Core and Back Sounds, North Carolina, USA, to relate the physical setting of seagrass beds, as measured by a wave exposure index (REI), tidal current speed and water depth, to various measures of the sedimentary environment, spatial heterogeneity of seagrass distribution and measures of seagrass abundance. Seagrass beds in this area form patterns ranging from continuous to semi-continuous to widely dispersed, discrete patches across a gradient of increasing hydrodynamic activity. Tidal current speeds, exposure to waves and relative water depths revealed strong correlative evidence that physical processes influenced landscape-scale (50 x 50 m range with …

Identifying Swelling-Activated Channels From Ion Selectivity Patterns, Dan R. Halm

Neuroscience, Cell Biology & Physiology Faculty Publications

No abstract provided.

Spinal Cord Compression: Histologic Spectrum Of Lesions, I. N. Soomro, N.Kayani N.Kayani, Shahid Pervez, A. S. Hussainy, R. Ahmed, S. Muzaffar, S. A. Aziz, S. H. Hasan

Department of Pathology and Laboratory Medicine

Histologic diagnosis ultimately determines the prognosis and treatment of lesions causing spinal cord compression. Modem imaging techniques have revolutionized the procedure of localizing lesions pre¬senting with signs and symptoms of spinal cord compression. As a result, these lesions are more accessible for fine needle aspiration and biopsy. A quick diagnosis is possible if cytologic preparation is made. Similarly, intraoperative frozen section facility not only provides rapid diagnosis, but also offers oppor tunity of appropriate management decision there and then. Histology in many cases needs help of special stains and immunocytochemistry. This study looks at the histologic spectrum of these lesions, …

The Location Of The Carboxy-Terminal Region Of Γ Chains In Fibrinogen And Fibrin D Domains, Michael W. Mosesson, Kevin R. Siebenlist, David A. Meh, Joseph S. Wall, James F. Hainfeld

Biomedical Sciences Faculty Research and Publications

Elongated fibrinogen molecules are comprised of two outer “D” domains, each connected through a “coiled-coil” region to the central “E” domain. Fibrin forms following thrombin cleavage in the E domain and then undergoes intermolecular end-to-middle D:E domain associations that result in double-stranded fibrils. Factor XIIIa mediates crosslinking of the C-terminal regions of γ chains in each D domain (the γXL site) by incorporating intermolecular ɛ-(γ-glutamyl)lysine bonds between amine donor γ406 lysine of one γ chain and a glutamine acceptor at γ398 or γ399 of another. Several lines of evidence show that crosslinked γ chains extend “transversely” between the strands of …

Identification Of Putative Cytoskeletal Protein Homologues In The Protozoan Host Hartmannella Vermiformis As Substrates For Induced Tyrosine Phosphatase Activity Upon Attachment To The Legionnaires' Disease Bacterium, Legionella Pneumophila, Chandrasekar Venkataraman, Lian-Yang Gao, Subbarao Bondada, Yousef Abu Kwaik

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Legionnaires' disease bacterium, Legionella pneumophila, is a facultative intracellular pathogen that invades and replicates within two evolutionarily distant hosts, free living protozoa and mammalian cells. Invasion and intracellular replication within protozoa are thought to be major factors in the transmission of Legionnaires' disease. We have recently reported the identification of a galactose/N-acetyl-d-galactosamine (Gal/GalNAc) lectin in the protozoan host Hartmannella vermiformis as a receptor for attachment and invasion by L. pneumophila (Venkataraman, C., B.J. Haack, S. Bondada, and Y.A. Kwaik. 1997. J. Exp. Med. 186:537–547). In this report, we extended our studies to the …

Expression Of Toxoplasma Gondii-Specific Heat Shock Protein 70 During In Vivo Conversion Of Bradyzoites To Tachyzoites, Neide M. Silva, Ricardo T. Gazzinelli, Deise A. O. Silva, Eloisa A. V. Ferro, Lloyd H. Kasper, Jose R. Mineo

Dartmouth Scholarship

Stage conversion between bradyzoites and tachyzoites was investigated in C57BL/6 mice chronically infected with the ME-49 strain of Toxoplasma gondii. In order to promote bradyzoite-tachyzoite conversion, mice were treated in vivo with neutralizing doses of anti-gamma interferon (IFN-gamma) or anti-tumor necrosis factor alpha (TNF-alpha) antibodies. Expression of parasite-specific antigens SAG-1, SAG-2, and heat shock protein 70 (Hsp-70) was visualized in the central nervous system by immunocytochemistry and measured by photometric assay. The immunosuppressive effect of anti-IFN-gamma or anti-TNF-alpha treatment was immediate, leading to parasite stage conversion as indicated by the increased expression of tachyzoite-specific antigens (SAG-1 and SAG-2) and by …

Update - July 1998, Loma Linda University Center For Christian Bioethics

Update

In this issue:

-- Christianity and Human Cloning - A Seventh-day Adventist Declaration of Ethical Principles
-- Cloning: Dolly's Mother is Her Sister!?
-- Hello, Dolly! Dolly! Dolly!

Expression Of Constitutively Active Raf-1 In The Mitochondria Restores Antiapoptotic And Leukemogenic Potential Of A Transformation-Deficient Bcr/Abl Mutant., P Salomoni, M A Wasik, R F Riedel, K Reiss, J K Choi, T Skorski, B Calabretta

Department of Microbiology and Immunology Faculty Papers

The oncogenic BCR/ABL protein protects hematopoietic cells from apoptosis induced by growth factor deprivation, but the mechanisms are only partially understood. A BCR/ABL mutant lacking amino acids 176-426 in the BCR domain (p185DeltaBCR) failed to protect interleukin 3-deprived 32Dcl3 myeloid precursor cells from apoptosis, although it possessed tyrosine kinase activity and was capable of activating the Ras-Raf-MAP kinase pathway. Compared to p185 wild-type transfectants, p185DeltaBCR-transfected cells showed markedly reduced levels of Bcl-2 and expressed the hypophosphorylated, proapoptotic form of BAD. Bcl-2 expression in the mitochondrial fraction of p185DeltaBCR cells was also markedly diminished and mitochondrial RAF was undetectable. In p185DeltaBCR …

Knowledge, Attitudes And Behavior Of African American Undergraduate College Students Concerning Primary Preventative Health, Lionas Mayes

McCabe Thesis Collection

African Americans' knowledge about primary preventive health and their attitudes toward primary preventive health influence their health behavior. Primary preventive health behavior is also affected by the individuals' definition of health and the significance they ascribe to their health status. Attitudes toward primary preventive health determine whether health assessment is important in preventing disease. African Americans have a myriad of views about health and general well being. The purpose of this study is to determine the relationship between primary preventive health knowledge, primary preventive health attitudes and primary preventive health behavior in African American undergraduate students. A survey will be …

Evaluation Of The Success Of Adoptive Versus Passive Transfer Of Immunity Against Trypanosoma Cruzi, Karen Powell

Masters Theses & Specialist Projects

Several investigators have demonstrated an increased resistance to the protozoal parasite Trypanosoma cruzi (the causative agent of Chagas' disease) in highly susceptible C3H mice when maintained at an environmental temperature of 36°C. This increased resistance is manifested as delay in onset of parasitemia, decreased parasitemia, decreased pathology, and increased longevity with eventual clearing of the parasite from the bloodstream. In addition, this enhanced resistance has been shown to be an immunologic phenomenon and not due to the direct effects of elevated temperature on the parasite itself. To ascertain the possible contributions of humoral vs. cellular immunity to the above phenomenon, …

The Sequential Role Of Lymphotoxin And B Cells In The Development Of Splenic Follicles, Mercedes Gonzalez, Fabienne Mackay, Jeffrey L. Browning, Marie H. Kosco-Vilbois, Randolph J. Noelle

Dartmouth Scholarship

The transfer of lymphocytes into severe combined immunodeficiency (SCID) mice induces a series of histological changes in the spleen, including the appearance of mature follicular dendritic cells (FDCs). Studies were undertaken to clarify the role of lymphotoxin (LT) in this process. The results show that SCID mice have a small and partially differentiated white pulp containing marginal zone and interdigitating dendritic cells, but lacking FDCs. Transferred spleen cells can segregate into T and B cell areas shortly after their injection to SCID mice. This ability is dependent on signaling through LT-β receptor (LT-βR), since blocking ligand–receptor interaction in recipient SCID …

The Second Messenger Camp Elicits Eating By An Anatomically Specific Action In The Perifornical Hypothalamus, Elizabeth Gillard, Arshad Khan, Rickinder Grewal, Bara Mouradi, Stefany Wolfsohn, B. Stanley

Selected Works Temporary Series

No abstract provided.

The Second Messenger Camp Elicits Eating By An Anatomically Specific Action In The Perifornical Hypothalamus, Gillard, Arshad Khan, Rickinder Grewal, Bara Mouradi, Stefany Wolfsohn, B. Stanley

Departmental Papers (Biology)

No abstract provided.

Antigen-Specific Cd8+ T Cells Protect Against Lethal Toxoplasmosis In Mice Infected With Neospora Caninum, Lloyd H. Kasper, Imtiaz A. Khan

Dartmouth Scholarship

Neospora caninum is a coccidial protozoan parasite that appears morphologically indistinguishable from Toxoplasma gondii and that infects a large range of mammals. Both inbred and outbred strains of mice exhibit a high degree of resistance to infection with N. caninum. Three inbred strains of mice (A/J, BALB/c, and C57BL/6) that were infected intraperitoneally with N. caninum were protected against a lethal challenge from T. gondii. Vaccine-induced protection was Neospora dose dependent. A rise in the CD8+ T-cell population in mice that had been vaccinated with N. caninum and challenged with T. gondii was observed. Adoptive transfer of CD8+ T-cell splenocytes …

Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward

Mathematics & Statistics Theses & Dissertations

The phenomenological modeling of the spatial distribution and temporal evolution of one-dimensional models of cancer dispersion are studied. The models discussed pertain primarily to the transition of a tumor from an initial neoplasm to the dormant avascular state, i.e. just prior to the vascular state, whenever that may occur. Initiating the study is the mathematical analysis of a reaction-diffusion model describing the interaction between cancer cells, normal cells and growth inhibitor. The model leads to several predictions, some of which are supported by experimental data and clinical observations $\lbrack25\rbrack$. We will examine the effects of additional terms on these characteristics. …

Enhancement Of Atp Levels And Glucose Metabolism During An Infection By Chlamydia: Nmr Studies Of Living Cells, David M. Ojcius, H. Degani, Joel Mispelter, Alice Dautry-Varsat

All Dugoni School of Dentistry Faculty Articles

The Chlamydia species are obligate intracellular bacteria that proliferate only within the infected cell. Since the extracellular bacteria are metabolically inert and there are no cell-free systems for characterizingChlamydia metabolism, we studied metabolic changes related to ATP synthesis and glycolysis in HeLa cells infected withChlamydia psittaci during the course of the 2-day infection cycle using noninvasive 31P and 13C NMR methods. We find that the infection stimulates ATP synthesis in the infected cell, with a peak of ATP levels occurring midway through the infection cycle, when most of the metabolically active bacteria are proliferating. The infection also stimulates synthesis of …

Subcellular Localization Of Mineralocorticoid Receptors In Living Cells: Effects Of Receptor Agonists And Antagonists, Géza Fejes-Tóth, David Pearce, Anikó Náray-Fejes-Tóth

Dartmouth Scholarship

Results on the subcellular localization of the mineralocorticoid receptor (MR) have been controversial. To determine the subcellular distribution and trafficking of the MR in living cells after binding of agonists and antagonists, we expressed a MR-green fluorescent protein (GFP) chimera in mammalian cells lacking endogenous MR. The GFP-tagged MR (GFP-MR) remained transcriptionally active, as determined in cotransfection experiments with the MR-responsive reporter, TAT3-LUC. The subcellular localization of GFP-MR was monitored by fluorescence time-lapse microscopy. In the absence of hormone, MR was present both in the cytoplasm and nucleus. Aldosterone induced a rapid nuclear accumulation of the MR. Aldosterone-bound GFP-MR was …

Vasodilators Activate Erythrocyte K-Cl Cotransport, Norma C. Adragna, H. Ahmed, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Investigation Of The Roles Of Toxin-Coregulated Pili And Mannose-Sensitive Hemagglutinin Pili In The Pathogenesis Of Vibrio Cholerae O139 Infection, Carol O. Tacket, Ronald K. Taylor, Genevieve Losonsky, Yu Lim

Dartmouth Scholarship

In this study, adult volunteers were fed tcpA and mshA deletion mutants of V. cholerae O139 strain CVD 112 to determine the role of toxin-coregulated pili (TCP) and mannose-sensitive hemagglutinin (MSHA) in intestinal colonization. Eight of 10 volunteers who received CVD 112 or CVD 112 ΔmshA shed the vaccine strains in their stools; the geometric mean peak excretion for both groups was 1.4 × 10⁵ CFU/g of stool. In contrast, only one of nine recipients of CVD 112 ΔtcpA shed vibrios in his stool (P < 0.01); during the first 24 h after inoculation, 3 × 10² CFU/g was recovered from this volunteer. All recipients of CVD …

A Vacuolar V–T-Snare Complex, The Predominant Form In Vivo And On Isolated Vacuoles, Is Disassembled And Activated For Docking And Fusion, Christian Ungermann, Benjamin J. Nichols, Hugh R. B. Pelham, William Wickner

Dartmouth Scholarship

Homotypic vacuole fusion in yeast requires Sec18p (N-ethylmaleimide-sensitive fusion protein [NSF]), Sec17p (soluble NSF attachment protein [alpha-SNAP]), and typical vesicle (v) and target membrane (t) SNAP receptors (SNAREs). We now report that vacuolar v- and t-SNAREs are mainly found with Sec17p as v-t-SNARE complexes in vivo and on purified vacuoles rather than only transiently forming such complexes during docking, and disrupting them upon fusion. In the priming reaction, Sec18p and ATP dissociate this v-t-SNARE complex, accompanied by the release of Sec17p. SNARE complex structure governs each functional aspect of priming, as the v-SNARE regulates the rate of Sec17p release and, …

Characterization Of The Promoter And Upstream Activation Sequences Of Sporulation-Specific Genes Spr1 (Ssg1) And Spr2 In Saccharomyces Cerevisiae, Sharmini S. Soosaithasan

Theses, Dissertations and Capstones

Sporulation is a developmental process in which temporally distinct sets of genes regulate the processes of meiosis and ascospore formation. Sporulation-specific genes are classified into early, middle, and late genes based on their peak time of expression during sporulation. Regulation of two late genes, SPR1 and SPR2, was studied. The function of SPR2 is unknown. Its regulatory region contains two Mid Sporulation Elements (MSE) repeated in tandem that are sufficient to confer sporulation-specific regulation to a CYCl-lacZ reporter. These sequences have UAS (upstream activation sequence) properties, as each 14 base pair element is sufficient to confer sporulation-specific regulation …

Neurotransmitter Transport: Models In Flux, Michael Kavanaugh

Biomedical and Pharmaceutical Sciences Faculty Publications

Physiologists say that ions and neutral solutes can cross biological membranes via “transporters” and “channels.” We tend to think about the difference between transporters and channels in terms of gating mechanisms. Ion channels exhibit a wide range of selectivity properties and permeation rates, but their gating at the most basic level can be thought of in terms of a single barrier or gate acting as a switch. When the gate is closed, ions can’t permeate; when the gate is opened, a permeation pathway for ions allows flux, often at very high rates (up to 10⁸/sec). Transporters and ion …

Excitatory Amino Acid Transporters Of The Salamander Retina: Identification, Localization, And Function, Scott Eliasof, Jeffrey L. Arriza, Barbara H. Leighton, Michael Kavanaugh, Susan G. Amara

Biomedical and Pharmaceutical Sciences Faculty Publications

The rapid re-uptake of extracellular glutamate mediated by a family of high-affinity glutamate transporter proteins is essential to continued glutamatergic signaling and neuronal viability, but the contributions of individual transporter subtypes toward cellular physiology are poorly understood. Because the physiology of glutamate transport in the salamander retina has been well described, we have examined the expression and function of glutamate transporter subtypes in this preparation. cDNAs encoding five distinct salamander excitatory amino acid transporter (sEAAT) subtypes were isolated, and their molecular properties and distributions of expression were compared. We report evidence that at least four distinct sEAAT subtypes are expressed …