Research Methods in Life Sciences Commons^™

Development Of A Model For Infective Endocarditis Via Intravenous Injection And Tooth Infection Of Rats Using Pathogenic Bacteria, Shahrokh Shabahang

Loma Linda University Electronic Theses, Dissertations & Projects

Historically, focal areas of infection have been linked to a number of systemic ailments. During the early part of the 20th century, patients who were suffering from inexplicable diseases and who were suspected of having infected teeth were referred to the dentist for multiple extraction of their dentition. The discovery of antibiotics provided a false sense of security that the war against microorganisms is no longer a concern for mankind. However, more recently, it has become common belief that increasing numbers of systemic diseases are linked to chronic infections. Recovery of bacteria from representative tissues has led investigators to believe …

Compendium Of Chemical Carcinogens By Target Organ: Results Of Chronic Bioassays In Rats, Mice, Hamsters, Dogs, And Monkeys, Lois Swirsky Gold, Neela B. Manley, Thomas H. Sloane, Jerrold M. Ward

Toxicology and Animal Models in Research Collection

Acompendiumof carcinogenesi s bioassay results organized by target organ is presented for 738 chemicals that are carcinogenic in chronic-exposure , long-term bioassays in at least 1 species. This compendium is based primarily on experiments in rats or mice; results in hamsters, monkeys, and dogs are also reported. The compendium can be used to identify chemicals that induce tumors at particular sites and to determine whether target sites are the same for chemicals positive in more than 1 species. The source of information is the Carcinogeni c Potency Database (CPDB), which includes results of 6073 experiments on 1458 chemicals (positive or …

Map Kinases In Cynomolgus Monkey Sperm Hyperactivation, Emily Nicole Haynes

Biological Sciences Theses & Dissertations

Mammalian sperm exhibit characteristic motility patterns, termed hyperactivated (HA) motility, associated with completion of capacitation. In cynomolgus monkey (Macaca fascicularis) sperm, this HA motility is dependent in vitro upon the addition of exogenous cyclic nucleotide mediators, caffeine and dibutyryl-cyclic adenosine monophosphate (dbcAMP). Previous reports have shown protein tyrosine phosphorylation to be an integral component of this caffeine- and cAMP-stimulated HA motility. This study investigated the involvement of the mitogen-activated protein (MAP) kinase-signaling cascade. Semen specimens were collected in Talp-HEPES medium from proven breeders via electroejaculation. After washing, sperm were incubated in the presence and absence of the MAP …

A Novel Strategy Utilizing Co-Expression Of Murine Il-12 And Antisense Tgf-Pl Against H238 Tumor Formation, Craig A. Seheult

Loma Linda University Electronic Theses, Dissertations & Projects

Cytokines have a profound effect on immune modulation, thus playing a significant role in cancer gene therapy. A variety of human carcinomas secrete transforming growth factor-beta (TGF-β), a cytokine with potent immunosuppressive properties. Suppressing TGF-β could be a key to successfully combating malignancies, such as gliomas, mammary, and colon cancers, that over-express TGF-β. Conversely, interleukin-12 (IL-12) is a potent immunostimulatory cytokine capable of regulating T and NK cell-mediated cytotoxic responses (Trinchieri, 1994) during an anti-tumor response. Activation of the immune system with such immunostimulatory cytokines renders it inert to the suppressive effects of TGF-β. To better understand these processes our …

Effects Of Liposome-Encapsulated Tnf-Alpha And Radiation Against Colon Cancer, Dong Won Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies have shown that tumor necrosis factor-α (TNF-α) can augment the antitumor effects of radiation, inhibiting tumor progression to a greater extent than either modality alone. However, nonspecific toxicities associated with TNF-α have limited its use as an adjuvant. This limitation is potentially resolved with the encapsulation of TNF-α in sterically stabilized, PEGylated liposomes (STEALTH®). Thus, the overall hypothesis of the research was that the combination of radiation with STEALTH® liposome encapsulated TNF-α (SL-TNF-α) will have greater efficacy and fewer dose-limiting side effects in the LS174T human colorectal tumor xenograft model compared to the combination of free TNF-α and …

The Effect Of Chronic Hypoxia On Cardiac Function In The Fetal Ovine Heart, Rodney David Rodrigo

Loma Linda University Electronic Theses, Dissertations & Projects

It has been shown that long-term high altitude hypoxia during pregnancy was associated with a decrease in cardiac contractility in fetal sheep. Given that hypoxia caused apoptotic cell death in fetal and neonatal rat cardiomyocytes, the present study tested the hypothesis that chronic hypoxia during pregnancy increases apoptosis in the fetal sheep heart. Pregnant (d 30) sheep were divided between normoxic control and chronically hypoxic (maintained at high altitude, 3,820 m, PaO₂: 60 Torr for 110 days) groups. Hearts were isolated from near-term (d 140) fetal sheep, and samples from all four chambers, right and left atria, and …

Age Related Changes In Contractile Sensitivity To Cyclic Gmp And Intracellular Calcium Compartmentalization In Ovine Arteries, Surya Margono Nauli

Loma Linda University Electronic Theses, Dissertations & Projects

The study examines the hypothesis that maturation changes the ability of cGMP to produce cerebral vasodilatation and alters the relative intracellular calcium pool sizes in ovine arteries. In ovine basilars taken from near-term fetal and young adult sheep, 8- pCPT-cGMP relaxed potassium- and serotonin-induced tone with pD2 values of 4.4±0.1 and 4.9±0.1 (fetal basilar) and 4.0±0.1 and 4.7±0.1 (adult basilar), respectively. In fura-2 loaded arteries, 8-pCPT-cGMP significantly lowered increases in cytosolic calcium concentration induced by serotonin but not potassium regardless of age. When calcium sensitivity was calculated in the same arteries as the slope of the relation between calcium concentration …

Optimum Bonding Time Of Four Different Curing Lights, Nathan Don Cotten

Loma Linda University Electronic Theses, Dissertations & Projects

With the development of new high-intensity curing lights, the time required to bond orthodontic brackets is steadily decreasing. The objective of this study was to determine the optimum curing time for bonding orthodontic brackets using four different visible curing lights (Standard Optilux 501, High Intensity Optilux 501 with Turbo Tip, Virtuoso Plasma Arc, and ESPE LED light). This study also tested the new generation of light emitting diode (LED) lights to determine if they can be used for bonding orthodontic brackets. Three hundred freshly extracted bovine teeth were mounted in acrylic resin and divided into 20 groups of 15 teeth …

Animal Research: A Review Of Developments, 1950–2000, Andrew N. Rowan, Franklin M. Loew

State of the Animals 2001

The third phase of the animal research debate started around 1950. After World War II the government became a major sponsor of scientific research, including biomedical research. The budget of the National Institutes of Health (NIH) grew dramatically and has continued to grow, with a few minor retrenchment periods, up to the present time (see Figure 1). This growth led to an enormous expansion in publicly funded research. In the private sector, the discovery of penicillin and streptomycin led to a tremendous expansion in pharmaceutical research and in the size of the prescription drug industry. These expansions in government funding …

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 …

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 …

Primate Numerical Competence: Contributions Toward Understanding Nonhuman Cognition, Sarah T. Boysen, Karen I. Hallberg

Sentience Collection

Nonhuman primates represent the most significant extant species for comparative studies of cognition, including such complex phenomena as numerical competence, among others. Studies of numerical skills in monkeys and apes have a long, though somewhat sparse history, although questions for current empirical studies remain of great interest to several fields, including comparative, developmental, and cognitive psychology; anthropology; ethology; and philosophy, to name a few. In addition to demonstrated similarities in complex information processing, empirical studies of a variety of potential cognitive limitations or constraints have provided insights into similarities and differences across the primate order, and continue to offer theoretical …

Periradicular Response Of Immunodeficient Rats To Mechanical Pulpal Exposure, James E. Stich

Loma Linda University Electronic Theses, Dissertations & Projects

Periradicular lesions develop as a result of the interaction between root canal irritants and the immune system. The purpose of this study was to investigate the periradicular response of immunodeficient rats to their oral flora. Twenty Sprague-Dawley rats received a total body irradiation dose of 750 cGy one week prior to the investigation. The pulps of the mandibular first molars of these animals and six nonirradiated rats were exposed mechanically with a ½ round bur and left open to the oral cavity. Additional irradiation (350 cGy) was administered bi-weekly to maintain immunosuppression. Periradicular specimens were obtained after two and four …

Role Of KAtp Channels In Reduced Antinociceptive Effect Of Morphine In Streptozotocin-Induced Diabetic Mice, Vivek Sood, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The nociceptive effect was measured using withdrawal latency in tail flick test in mice rendered diabetic by administering streptozotocin (200 mg/kg, i.p.). The antinociceptive effect of morphine (4 and 8 mg/kg, s.c.) and cromakalim, a KATP channel opener, (0.3, 1 and 2 micrograms, i.c.v.) was significantly reduced in diabetic mice. Moreover, co-administration of cromakalim(0.3 microgram) did not alter the reduced antinociceptive effect of morphine(4 mg/kg) in diabetic mice. Spleenectomy in diabetic mice restored the decrease in antinociceptive effect of morphine and cromakalim. Multiple dose treatment with insulin to maintain euglycaemia for 3 days in diabetic mice prevented the decrease in …

Effect Of Actinomycin D And Cycloheximide On Ischemic Preconditioning-Induced Delayed Cardioprotective Effect In Rats, Devinder Singh, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The present study was designed to investigate the effect of actinomycin D, a transcription inhibitor, and cycloheximide, a translation inhibitor, on the delayed cardioprotective effect of ischemic preconditioning. Left thoracotomy was performed in anaesthetized rats at 4th/5th intercostal space and polypropylene suture (5-0) was employed to occlude left common coronary artery. Ischemic preconditioning was produced by four episodes of 5 min of coronary artery occlusion followed by 5 min of reperfusion and thoracic cavity was sutured. Left thoracotomy was performed again after 24 hr of ischemic preconditioning and left coronary artery was occluded for 30 min followed by reperfusion for …

Arkansas Animal Science Department Report 1999, Zelpha B. Johnson, D. Wayne Kellogg

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

The Role Of Brn-3.2 In Retinal Ganglion Cell Differentiation, Jerin Marie Wright

Loma Linda University Electronic Theses, Dissertations & Projects

Within the retina, the POU domain of transcription factors brn-3.0, brn-3.1, and brn-3.2 are present only in retinal ganglion cells. These genes are believed to be involved in establishing neural cell lineages in mammals. In this study brn-3.2 was examined by comparing the number of ganglion cells present during postnatal development in normal mice (+/+), in mice homozygous (-/-) for the brn-3.2 gene, and in adult mice with a heterozygous gene deletion (+/-) for brn-3.2. Optic nerve cross sections were imaged by electron microscopy, and axon profiles counted systematically by hand. These counts were then related to the nerve cross …

Neuronal And Metabolic Increases In Pedunculopontine Nucleus Of Parkinson's Rats, Jonathan Dennis Carlson

Loma Linda University Electronic Theses, Dissertations & Projects

The theoretical mechanisms underlying the symptoms of Parkinson’s disease are based on dysfunctional output from the basal ganglia projected to the cortex via the thalamus. However, the subthalamic nucleus (STN) and substantia nigra pars reticularis (SNr) as part of the basal ganglia, also project to the brainstem, in particular to the pedunculopontine nucleus (PPN). Both the STN and SNr have altered neuronal activity in the 6-hydroxydopamine (6-OHDA) Parkinson’s model rat. Thus, it is hypothesized that the PPN is altered in this model of Parkinson’s disease.

This hypothesis was examined by comparing the rates of glucose metabolism and spontaneous neuronal activity …

Effect Of Obturation And / Or Coronal Seal On The Success Of Root Canal Therapy : An In Vivo Histologic Investigation, Douglas Snider

Loma Linda University Electronic Theses, Dissertations & Projects

Numerous studies have examined coronal leakage with in vitro protocols. A search of the literature showed the absence of a long term in vivo, histologic study, examining the effect of coronal and/or radicular leakage on periradicular health.

The purpose of this study was to evaluate the effect of obturation and / or coronal seal in preventing the formation of periradicular lesions in dogs over time. The study was conducted on six beagle dogs. Premolars were cleaned and shaped. Sixteen roots in each dog were randomly assigned to one of four treatment groups of equal size. Group one was obturated using …

Insulinlike Growth Factor 1- And 2-Augmented Collagen Gel Repair Of Facial Osseous Defects, James S. Toung, Roy C. Ogle, Raymond F. Morgan, William H. Lindsey

School of Medical Diagnostics & Translational Sciences Publications

BACKGROUND: Defects of the facial bone structure are common problems for the facial plastic surgeon. Native type 1 collagen gels (T1CGs) have been shown to mediate repair of facial critical-size defects in rat models.

OBJECTIVE: To evaluate the efficacy of T1CG augmented with insulinlike growth factor (IGF) 1, IGF-2, and a combination of IGF-1 and IGF-2 on the repair of facial critical-size defects in a rodent model.

METHODS: Twenty-four retired male breeder Sprague-Dawley rats were divided into 4 groups of 6 animals. Facial critical-size defects were created by removing the nasalis bones with a bone-cutting drill. Defects were treated with …

Arkansas Animal Science Department Report 1998, Stacey Gunter

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Research Fundamentals: V. The Use Of Laboratory Animal Models In Research, Brian J. O'Neil, Jeffrey A. Kline, Keith Burkhart, John Younger

Biomedicine and Animal Models in Research Collection

Animal research has provided important information about many aspects of the pathophysiology of human disease. Well-performed animal studies can determine the potential benefit of many proposed therapeutic interventions, and experimental results from animal studies have served as the basis for many landmark clinical trials. Many animal research models are described in the research literature, and choosing the appropriate model to answer a research question can be a daunting task. Even more challenging is developing a new model when none of the existing systems are relevant to the proposed question. This article was prepared by members of the SAEM Research Committee …

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.

Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie

Loma Linda University Electronic Theses, Dissertations & Projects

Active transport via Na⁺, K⁺-ATPase plays an important role in establishing and maintaining proper ionic gradient across all mammalian cell membranes. A strict regulation of Na⁺, and K⁺ ion levels is especially important in excitable cells such as neurons and myocytes. Inhibition of the enzyme is associated with several pathological conditions and has serious detrimental effects on cerebral cortical cells. Yet the enzyme appears to be limited in amount and distribution in newborn rats. In this study, Na_⁺, K⁺- ATPase expression and distribution in early postnatal rats were studied …

A Model Using Radiation And Pws4-Htnf-Α Gene Therapy For Treatment Of Glioblastomas, Angelo G. Baher

Loma Linda University Electronic Theses, Dissertations & Projects

The efficacy of radiotherapy for cancer is limited by the dose that can be safely delivered to the tumor without causing debilitating side effects. In addition, successful treatment of highly malignant tumors such as glioblastomas is likely to require adjunctive therapies to enhance tumor response to radiation. Previous studies have shown immunomodulation and a synergestic reduction in tumor volume of malignant tumors when tumor necrosis factor-α (TNF-α) protein is administered prior to radiation. The major goal of the present investigation was to evaluate the efficacy of pWS4-human TNF-α (pWS4-hTNF-α), a new plasmid construct that expresses human TNF-α protein, together with …

Regeneration In Periodontal Defects With Rhbmp-2 : A Dosage Study, Paola Guglielmoni

Loma Linda University Electronic Theses, Dissertations & Projects

Bone morphogenetic proteins (BMPs) have been shown to induce bone formation in ectopic and orthotopic sites. This inductive capability has led to their evaluation as possible adjuncts in periodontal reconstructive therapy. Indeed, studies have reported periodontal regeneration following surgical implantation of recombinant human BMP-2. This study evaluated regeneration of alveolar bone and cementum following periodontal reconstructive surgery including implantation of a construct consisting of sterile lyophilized rhBMP-2 in buffer adsorbed onto an absorbable collagen sponge. Critical size mandibular supra-alveolar periodontal defects were surgically created, and an incomplete block design was used to evaluate the regenerative potential of rhBMP-2 at 0.05, …

Psychology's Use Of Animals: Current Practices And Attitudes, Kenneth J. Shapiro

Experimentation Collection

In this chapter, I present a psychology primer for the uninitiated, with special emphasis on psychology's uses of animals. After sketching the scope of the field generally, I review available data on present numbers and species of animals used in psychological research, level of suffering induced and current trends. I also provide several concrete examples of psychological research involving animals. Finally, the chapter concludes with a presentation of attitudes of psychologists toward animals and these practices.

A Cytochemical Evaluation Of Blood-Brain Barrier Sodium, Potassium- And Calcium-Adenosine Triphosphatase Polarity, Panya Steve Manoonkitiwongsa

Loma Linda University Electronic Theses, Dissertations & Projects

The blood-brain barrier (BBB) is formed by cerebral vascular endothelial cells. Brain ion and fluid homeotasis essential for proper neural functioning is due to the BBB. Sodium-potassium and calcium-activated adenosine triphosphatase (Na⁺, K⁺-ATPase and Ca²⁺-ATPase) serve as one of the main mechanisms controlling brain Na⁺, K⁺, and Ca²⁺ concentrations. The present accepted concept is that both of these enzymes are localized to the abluminal plasma membrane of endothelial cells although there have been contrary results from some studies. Because of these discrepancies, further work was needed. Various cytochemical procedures …

The Effect Of Systemic Doxycycline On Alveolar Bone Loss Following Periradicular Surgery, G. Reed Cummings

Loma Linda University Electronic Theses, Dissertations & Projects

Studies have shown an average of 0.5 mm to over 1.0 mm of bone loss following full thickness flap reflection. Recent investigations have revealed that the tetracycline family of antibiotics can prevent bone loss. The purpose of this study was to determine the effect of systemic Doxycycline on crestal alveolar bone loss following periradicular surgery in Beagle dogs.

The experiment was divided into two phases. The first phase served as the control (Non-Doxycycline), the second phase as the experiment (Doxycycline). Full thickness flaps were reflected in the mandibular left or right quadrant (control side) of five Beagle dogs. Using a …