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Full-Text Articles in Research Methods in Life Sciences

Histomorphometric Analysis Of Primate Periodontal Tissues Following Corticotomy In Orthodontics, Wuiteng Koh Jun 1991

Histomorphometric Analysis Of Primate Periodontal Tissues Following Corticotomy In Orthodontics, Wuiteng Koh

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the prevalence of specific cell types and structures at the active tooth movement site in corticotomized and non-corticotomized specimens obtained from a previous study, and to consider the hypothesis that corticotomy facilitated orthodontics is efficacious due to an inflammatory response rather than tooth-bone block movement. Specimens from 3 monkeys, each of which had a treatment and control quadrant in each arch, were sectioned, mounted on glass slides, and stained with Giemsa, haematoxylin, and Safranin stains. A histomorphometric analysis was performed with DataVoice™, a voice activated computer system which allowed for digitization of …


Catecholamines And The Regulation Of Uterine Contractions In The Pregnant Rhesus Macaque, Cahleen Mae Mcnutt Mar 1991

Catecholamines And The Regulation Of Uterine Contractions In The Pregnant Rhesus Macaque, Cahleen Mae Mcnutt

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to test the hypothesis that: 1) maternal and/or amniotic fluid catecholamines or prostaglandins display nocturnal activity rhythms similar to those of the myometrial contractility in the pregnant rhesus macaque and, 2) catecholamines stimulate prostaglandin production by fetal membranes. Paired maternal arterial blood and amniotic fluid samples were collected at 0900 h (AM) and 2100 h (PM) from chronically catheterized rhesus macaques until delivery and analyzed for prostaglandin metabolites (PGFM and PGEM-II) and catecholamines (norepinephrine, epinephrine, and dopamine). Uterine activity data was continuously recorded. A rhythm in uterine contractility was observed, with peak activity between 1900 and …


Topographic Development Of The Corticocollicular Projection In The Neonatal Rat, F. Allen Richburg Ii Mar 1991

Topographic Development Of The Corticocollicular Projection In The Neonatal Rat, F. Allen Richburg Ii

Loma Linda University Electronic Theses, Dissertations & Projects

The density and distribution of labeled cortical cells was examined following discrete deposits of retrograde tracers into the superior colliculus (SC) of neonatal and adult rats to study the topographic order of SC afferents from the cortex during the initial phase of axon ingrowth. Small deposits of red and green latex microspheres (0.02-0.05ul) were placed into the SC of rats ranging in age from birth to adulthood using glass micropipettes (tip diameter 25-35um). The animals, following a 48hr survival period, were deeply anesthetized and perfused with normal saline followed by a 10% formal-saline solution. The brains were sectioned coronally at …


Animals In Biomedical Research: The Undermining Effect Of The Rhetoric Of The Besieged, John P. Gluck, Steven R. Kubacki Jan 1991

Animals In Biomedical Research: The Undermining Effect Of The Rhetoric Of The Besieged, John P. Gluck, Steven R. Kubacki

Experimentation Collection

It is correctly asserted that the intensity of the current debate over the use of animals in biomedical research is unprecedented. The extent of expressed animosity and distrust has stunned many researchers. In response, researchers have tended to take a strategic defensive posture, which involves the assertation of several abstract positions that serve to obstruct resolution of the debate. Those abstractions include the notions that the animal protection movement is trivial and purely anti-intellectual in scope, that all science is good (and some especially so), and the belief that an ethical consensus can never really be reached between the parties.


Life History, Ecology, And Morphology Of The Ravine Salamander, Plethodon Richmondi, Ronnie D. Jewell Jan 1991

Life History, Ecology, And Morphology Of The Ravine Salamander, Plethodon Richmondi, Ronnie D. Jewell

Theses, Dissertations and Capstones

The distribution of P. richmondi and P. cinereus has been of interest to herpetologist for many years. Plethodon cinereus is found throughout the state except for part of the Allegheny Plateau Province where P. richmondi occurs. There is a somewhat abrupt end to their ranges where they overlap which does not appear to be influenced by elevational differences, vegetation patterns, or general climatic changes. The propose of this study was to determine if temperature and/or moisture are limiting the distribution of P. richmondi and P. cinereus in West Virginia. The natural history of P. richmondi has not in West Virginia …


Reflective Ethology, Applied Philosophy, And The Moral Status Of Animals, Marc Bekoff, Dale Jamieson Jan 1991

Reflective Ethology, Applied Philosophy, And The Moral Status Of Animals, Marc Bekoff, Dale Jamieson

Experimental Research and Animal Welfare Collection

Currently there is an unprecedented interest in ethological studies of nonhuman animals. Much of this interest is motivated by a desire to learn more about animals themselves. For scientists assuming this stance, a secondary goal is to use this knowledge to assess the place of humans in the natural order of things, stressing continuity or discontinuity depending on one's views. Others, however, study animals primarily to apply this knowledge to human behavior. We argue that behavioral research demands the rigorous application of methods that are minimally harmful to the animals being studied. We argue for a moderate, but rigorous and …


Pharmacokinetics And Effects On Blood Chemistry Of Cyclosporine In Human Infants And Kid Goats, Floyd A. Beierle Dec 1990

Pharmacokinetics And Effects On Blood Chemistry Of Cyclosporine In Human Infants And Kid Goats, Floyd A. Beierle

Loma Linda University Electronic Theses, Dissertations & Projects

Kid goats (newborn) have been used in transplantation protocols to study the techniques and problems of infant human cardiac transplantation. Immunosuppression has been by cyclosporine in both species. However, the pharmacokinetics of cyclosporine (CSA) in both the kid goat and human infant were unknown. Therefore, the pharmacokinetics of CSA were investigated. A single dose study and a long term chronic administration study were undertaken in the goat. Six Nubian goats, ages 60-90 days, were given a single IV dose of CSA, 0.25 mg/kg, over a 10 minute period and 72 hr later an oral cyclosporine dose of 20 mg/kg. The …


Proto-Oncogene Regulation By Growth Factors In Bone Cells, Harold Lyndon Merriman Aug 1990

Proto-Oncogene Regulation By Growth Factors In Bone Cells, Harold Lyndon Merriman

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies have shown that bone cells in culture produce a number of growth factors that are important in bone regulation. Chick and mouse primary calvarial cultures consist of a mixture of cell types that make it difficult to interpret the results from these model systems. In contrast, MC3T3-E1 cells are a clonal mouse osteoblast-like cell line. Since MC3T3-E1 cells consist of a single population of calvarial cells, they make an ideal system in which to study the autocrine effects of bone growth factors.

Based on this work, MC3T3-E1 cells are now known to produce IGF-I, TGF-beta and IGF-II in …


Effect Of Glucose Administration On Hamster Liver S9-Mediated Mutagenesis, Metabolism And Dna-Binding Of Benzo[A]Pyrene And Aflatoxin B1, Daniel C. Rubano Jun 1990

Effect Of Glucose Administration On Hamster Liver S9-Mediated Mutagenesis, Metabolism And Dna-Binding Of Benzo[A]Pyrene And Aflatoxin B1, Daniel C. Rubano

Loma Linda University Electronic Theses, Dissertations & Projects

Hamster liver S9 prepared from control animals and animals given 30% glucose in drinking water 48 h before time of sacrifice was used in studies of benzo[a]pyrene (BaP) and aflatoxin (AFB1)-induced mutagenesis, metabolism of BaP and AFB1, and metabolite binding to calf thymus DNA. BaP-induced mutagenesis in Salmonella typhimurium TA100 was reduced 38.5% while AFB1-induced mutagenesis was increased 36% by S9 from glucose-treated hamsters. The reduction of [3H]BaP metabolite binding to calf thymus DNA in incubations with S9 from glucose-treated hamsters correlated with a decrease in unknown BaP metabolite-deoxyribonucleoside adducts isolated by …


Alternatives To And Reduction Of Animal Use In Biomedical Research, Education And Testing, John M. Frazier, Alan M. Goldberg Jan 1990

Alternatives To And Reduction Of Animal Use In Biomedical Research, Education And Testing, John M. Frazier, Alan M. Goldberg

Experimentation Collection

Biomedical endeavours can be divided into three major categories: research, education, and testing. Within the context of each of these categories, activities involving whole animals have made major contributions and will continue to do so in the future. However, with technological developments in the areas of biotechnology and computers, new methods are already reducing the use of whole animals in certain areas. This article discusses the general tissues of alternatives and then focuses on the development of new approaches to toxicity testing.


Understanding Dogs Through Kinesthetic Empathy, Social Construction, And History, Kenneth J. Shapiro Jan 1990

Understanding Dogs Through Kinesthetic Empathy, Social Construction, And History, Kenneth J. Shapiro

Sentience Collection

The term, "come into animal presence," she takes from the title of a Denise Levertov poem. The poem, which reads, in part, "What joy when the insouciant armadillo glances at us and doesn't quicken his trotting across the track into the palm bush. What is this joy?" This joy is the possibility of our being in the presence of animals for "(t)he armadillo has some intention to pursue in the palm forest." This joy, to which I invite you here, consists in dwelling in that presence, in inhabiting that intention, that armored but guileless world of the armadillo. I will …


Effects Of Dietary Corn Oil And Menhaden Oil On Rats Mammary Tumorigenesis And Prostaglandin E2 Levels, Melissa L. Philley Aug 1989

Effects Of Dietary Corn Oil And Menhaden Oil On Rats Mammary Tumorigenesis And Prostaglandin E2 Levels, Melissa L. Philley

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Melissa L. Philley on August 4, 1989.


Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure Aug 1989

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …


The Effect Of An Anti-Osteoclastic Agent And A Collagen Sponge On Root Resorption Following Regenerative Periodontal Surgery In The Dog, Rudolf Hahn Aug 1989

The Effect Of An Anti-Osteoclastic Agent And A Collagen Sponge On Root Resorption Following Regenerative Periodontal Surgery In The Dog, Rudolf Hahn

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies indicate that root resorption is a frequent sequela to significant amounts of periodontal repair following experimental regenerative periodontal surgical procedures in animal models. To study if root resorption can be reduced or prevented, periodontal repair was evaluated in large horizontal circumferential defects in the dog in the absence of influence from the oral environment. Diphosphonate (Cl2 MDP) applied topically to the root surfaces prior to wound closure as well as the use of a collagen sponge membrane (Helistat®) draped over the root surfaces and a control with no additional treatment after defect creation were the modalities employed. …


In Vitro Evaluation Of Cancer Patient Immune Responses Following Infusion Of Radiolabeled Murine Monoclonal Antibody, Kelly A. King Jun 1989

In Vitro Evaluation Of Cancer Patient Immune Responses Following Infusion Of Radiolabeled Murine Monoclonal Antibody, Kelly A. King

Loma Linda University Electronic Theses, Dissertations & Projects

Several monoclonal antibody (MAb) types derived from mice have been developed specifically for the use of targeting human tumors. The specificity of these murine MAb’s for their respective tumor antigens is very high making them potentially good immunotherapeutic agents for cancer treatment and diagnosis. A limiting factor in using these murine MAb’s in patients is the development of human anti-mouse antibody (HAMA). The presence of HAMA may reduce the effectiveness of MAb for tumor targeting. If patient sensitization could be quickly detected following the initial infusion of MAb, then future infusion could be altered or terminated to prevent further sensitization. …


Enhancement Of Intratumor Antibody Distribution With A Bifunctional Antibody Delivery System And With Hyperthermia, Karen Lynn King Jun 1989

Enhancement Of Intratumor Antibody Distribution With A Bifunctional Antibody Delivery System And With Hyperthermia, Karen Lynn King

Loma Linda University Electronic Theses, Dissertations & Projects

The intratumor distribution of a new monoclonal antibody-hapten-based delivery system was examined. From two marine antibodies, Hybritech, Inc. has developed a bifunctional antibody (BPA) with specificities against CEA (ZCE-025 or GEM 231) and against one of two derivatives of [111In]-benzyl-EDTA (CHA 255), EOTUBE or BLEDTA IV, to form ZCE/CHA or CEM/CHA. BFA accumulates in CEA-expressing tissue and clears from non-antigenic tissues prior to administration of an [111In]-hapten.

Using five groups of nude mice bearing human colon tumor xenografts (T380), we evaluated different carriers of [111In]-EOTUBE to prelocalized ZCE/CHA. We administered all antibodies and haptens …


Autonomic Nervous System And Cholesterol Transport, Yuan-Line Hung Jun 1989

Autonomic Nervous System And Cholesterol Transport, Yuan-Line Hung

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of autonomic nervous system on cholesterol transport is of clinical interest because the relationship between lipoprotein metabolism and atherogenesis is expressed in coronary artery disease.

Generally speaking, beta blockers increase serum VLDL level but decrease both HDL and HDL2 cholesterol levels without affecting the LDL in humans. We are unaware of reports concerning the effects of metoprolol on lipoprotein metabolism nor comparison of the effects of metoprolol and propranolol in the unhandled rat model. In part I we employed the unhandled rats to compared the effects of these 2 drugs administered with the drinking water in order …


Regeneration Of Meissner Corpuscles In Diabetic Mice Following Median Nerve Crush, Bonnie J. Forrester May 1989

Regeneration Of Meissner Corpuscles In Diabetic Mice Following Median Nerve Crush, Bonnie J. Forrester

Loma Linda University Electronic Theses, Dissertations & Projects

The hyperglycemic metabolic condition found in diabetes mellitus leads to the development of sensory neuropathies and causes delayed and incomplete neuronal regeneration. Diabetic sensory neuropathy has been shown to contribute to the impairment of light touch and low frequency vibratory perception. It is proposed that the regeneration of receptors that detect these sensations will be delayed and incomplete in diabetic animals with uncontrolled hyperglycemia. This study addresses the effects of diabetes on the regeneration of Meissner corpuscles, distal sensory endings that perceive light touch and low frequency vibration.

Corpuscles from 60 diabetic mice, and their age-matched, non-diabetic littermates, were examined …


Weaning Kimberley Cattle Pays Off, D Pratchett, Stuart Young Jan 1989

Weaning Kimberley Cattle Pays Off, D Pratchett, Stuart Young

Journal of the Department of Agriculture, Western Australia, Series 4

Research results show that weaning Kimberley calves when they reach 140kg liveweight is one way of increasing herd productivity by changing management practices. However, removing the bulls from the breeding herd, rather than running them with the cows ywear round as is the practice, does not increase branding percentage.


The Prenatal Development Of The "Synaptic" Structures In The Guinea Pig Pineal Gland, Zhongrong Luo Dec 1988

The Prenatal Development Of The "Synaptic" Structures In The Guinea Pig Pineal Gland, Zhongrong Luo

Loma Linda University Electronic Theses, Dissertations & Projects

Pineal "synaptic" ribbons are a heterogeneous population of organelles. In addition to "synaptic" ribbons (SR) sensu stricto, which are electron-dense rods, "synaptic" spherules (SS) and intermediate forms (IMF) are present. The SS are electron-dense spherical structures, the diameter of which is two to three times the width of the SR. The IMF appear as irregularly formed structures. The SR, SS and IMF are surrounded by electron-lucent vesicles. Their function and origin are unknown and also a knowledge of their prenatal development is lacking. In order to gain an insight into the development of the "synaptic structures, the pineal glands …


The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga Sep 1988

The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga

Loma Linda University Electronic Theses, Dissertations & Projects

A deleterious effect of spaceflight on human health is the loss of bone associated with the prolonged lack of gravitational stress on the skeleton. A potential for bone loss is indicated by the hypercalciuria and decreased heel bone density determined in Skylab astronauts. Histological studies of juvenile laboratory rats in actual spaceflight and in simulation models document a suppression of bone formation with little alteration of bone resorption. The mechanism for net bone loss needs to be defined in order to develop measures for its prevention or correction.

Skeletal growth factors, which may mediate coupling and locally regulate bone volume …


Age-Related Changes In Meissner Corpuscles Of Diabetic Mice As Observed By Electron Microscopy, Vicky R. Ras Sep 1988

Age-Related Changes In Meissner Corpuscles Of Diabetic Mice As Observed By Electron Microscopy, Vicky R. Ras

Loma Linda University Electronic Theses, Dissertations & Projects

Light touch and low-frequency vibration sense are often impaired in diabetic patients. Meissner corpuscles are distally located mechanoreceptors that respond to these stimuli. Peripheral sensory neuropathy in diabetes progresses from distal to proximal, therefore, Meissner corpuscles are ideally suited to study diabetic neuropathy in the C57BL/Ks (db/db) mouse.

Corpuscles from the forepaw digital pads of 9 diabetic and 9 nondiabetic littermates were studied by electron microscopy. These were divided into 3 age groups; 2.5 months, 10 months, and 17 months old.

Ultrastructural changes observed within various receptor components were myelin figures, multivesicular bodies, vacuoles, basal lamina duplication, abnormal and enlarged …


A [6-14c] Glucose Autoradiographic Study Of The Rat Brainstem Under Hypercapnic And Hypocapnic Conditions: Identification Of Respiratory-Related Regions, Tobey M. Leung Aug 1988

A [6-14c] Glucose Autoradiographic Study Of The Rat Brainstem Under Hypercapnic And Hypocapnic Conditions: Identification Of Respiratory-Related Regions, Tobey M. Leung

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of systemic hypercapnia on brainstem metabolism were studied with the [6-14C] glucose autoradiography method. Neuronal pools which are metabolically active take up more [6-14C] glucose and maybe revealed pictorially as darker areas on autoradiograms. Since a high concentration of carbon dioxide stimulates central chemoreceptors and hence enhances respiratory drive, the darker regions on the autoradiograms may represent regions concentrated with respiratory-related neurons. Two discrete regions in the ventrolateral medulla (a column near nucleus ambiguus and a column in the lateral reticular nucleus) appeared dark and were analyzed with an image processing system, which converted …


Decreased Triiodothyronine Binding To The Hepatic Nuclear Thyroid Hormone Receptor In The Diabetic Mouse, Thomas J. Dewind Jun 1988

Decreased Triiodothyronine Binding To The Hepatic Nuclear Thyroid Hormone Receptor In The Diabetic Mouse, Thomas J. Dewind

Loma Linda University Electronic Theses, Dissertations & Projects

The diabetic C57BL/KsJ-db m mouse has abnormal thyroid hormone levels and indications of thyroid hormone resistance. To investigate the basis of these abnormalities, the hepatic nuclear thyroid hormone receptor was extracted with 0.4 M KCl, 1.1 mM MgCl2, 20 mM Tris/HCl, pH 7.9 from hepatocyte nuclei of normal C57BL/KsJ, heterozygous C57BL/KsJ-db m (db/m), and diabetic C57BL/KsJ-db m (db/db) mice. Normal and heterozygous mice were grouped together as the controls. Triiodothyronine (T3) binding studies at 4°C using nitrocellulose filtration to separate free T3 from receptor bound T3 demonstrated an …


Effects Of Corticosteroids And Of Cyclosporin A On Trypanosoma Musculi In Mice And In Culture, Philip Stephen Schuyler Jun 1988

Effects Of Corticosteroids And Of Cyclosporin A On Trypanosoma Musculi In Mice And In Culture, Philip Stephen Schuyler

Loma Linda University Electronic Theses, Dissertations & Projects

The in vivo and in vitro effects of cyclosporin A and corticosteroids on Trypanosoma musculi were examined. Mice that received continuous administration of 6 mg/liter/day of dexamethasone in drinking water and 200 mg/kg hydrocortisone acetate as a single dose 24 hrs prior to injection with T. musculi had significantly higher and longer parasitemias, than controls. Body and spleen weights and B cell responsiveness were lower in test animals and there were some deaths. Mice injected with T. musculi that received 100 mg/kg/day cyclosporin A had longer, but not higher, parasitemias than controls. Corticosteroids appear to partially inactive antibody production (i.e. …


Electromagnetic Field Variations In The Activation Of Bone Cell Synthesis, Gary Ketcherside Apr 1988

Electromagnetic Field Variations In The Activation Of Bone Cell Synthesis, Gary Ketcherside

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]


Inventing The Skin You Love To Test, Rick Weiss Feb 1988

Inventing The Skin You Love To Test, Rick Weiss

Popular Press Items

No abstract provided.


Policy For Identifying And Assessing The Health Risks Of Toxic Substances, Maine Bureau Of Health Feb 1988

Policy For Identifying And Assessing The Health Risks Of Toxic Substances, Maine Bureau Of Health

Maine Collection

Policy for Identifying and Assessing the Health Risks of Toxic Substances

by Norman T. Anderson, Environmental Toxicology Program, Division of Disease Control, Bureau of Health (February, 1988).

Contents: Section I: Introduction / Section II: Methods / Section III: Exposure Assessment / Section IV: Hazard Identification / Section V: Hazard Assessment / Section VI: Risk Characterization / List of Figures / List of Tables


A New Invasiveness Scale: Its Role In Reducing Animal Distress, Kenneth J. Shapiro, Peter B. Field Jan 1988

A New Invasiveness Scale: Its Role In Reducing Animal Distress, Kenneth J. Shapiro, Peter B. Field

Experimentation Collection

No abstract provided.


Hyperosmotic Modification Of Brain Extracellular Space And Blood-Brain Barrier In The Rat As Observed By Electron Microscopy, Susan A. Meacham Dec 1987

Hyperosmotic Modification Of Brain Extracellular Space And Blood-Brain Barrier In The Rat As Observed By Electron Microscopy, Susan A. Meacham

Loma Linda University Electronic Theses, Dissertations & Projects

The highly selective permeability of cerebral blood vessels, termed the blood-brain barrier, is due to endothelial tight junctions (zonulae occludentes). Hyperosmotic solutions reversibly open the blood-brain barrier. The purpose of this study is to determine the immediate effect of hyperosmotic arabinose perfusion upon the cerebrovascular endothelium, the morphology of the cerebral cortex, and the cortical extracellular space.

Twelve adult male Sprague-Dawley rats were separated into three groups of four animals each: control, intermediate, and extreme. Controls were perfused with a Tyrode's solution prewash followed by trialdehyde fixative. The intermediate group received a prewash of 740 mmol/kg arabinose followed by the …