Research Methods in Life Sciences Commons^™

Histologic Comparison Of Apical Tissue Response To Endodontic Overfills With Gutta Percha And Grossman's Sealer Vs. Sargenti Method (N₂), Donald L. Brewer

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared endodontic overfills of N₂ and gutta percha-Grossman's Sealer from a histopathological basis. The study employed four male rhesus monkeys and a sample of 31 teeth.

The most obvious difference between the samples filled with N₂ and the gutta percha-Grossman's Sealer samples was the recurring presence of ankylosis in the N₂-treated teeth. Results also included bone necrosis, inflammation and root and bone resorption.

The N₂ samples were considered to have evidenced greater violence of reaction apically.

Effects Of Cocaine, Nicotine And Diet On Voluntary Alcohol Consumption In Rats, Zaida Raquel Cordero Loayza

Loma Linda University Electronic Theses, Dissertations & Projects

The consumption of alcohol is a problem not only in this country (U.S.), but also in many other places in the world. Thus we find the Indians in Peru, Bolivia and other neighboring countries (Ecuador and northern part of Argentina) consuming alcohol to the point that they become alcoholics, in addition to this they also chew coca leaves, plant from which cocaine is extracted.

In an effort to establish the cause for this behavior, we put Sprague-Dawley albino rats on either a poor or good basal diet. Once every other day the rats were injected with a solution of cocaine. …

Viability Of Dentin In Rats Incisors : Fluid Movement In Pulpless, Endodontically Treated, And Normal Teeth In Rats, Maria Luisa Canales

Loma Linda University Electronic Theses, Dissertations & Projects

It is a well established fact that there is a fluid transport system through the dentin, however to the present time very little has been done regarding this system in teeth that have been endodontically treated.

The present work was conducted in vivo using the lower incisors of rats as the medium for the study.

A selected number of Sprague Dawley rats (36 animals), whose average age was 60 days, and whose body weight averaged about 180 grams, were given an anesthetic of Sodium Pentabarbitol, .05 to .07 ml. per 100 grams body weight. This anesthetic was injected intraperitoneally.

The …

The Effect Of Post-Operative Use Of Chlorhexidine On Periodontal Regeneration In Monkeys With Chronic Bifurcation Defects, J. Pat Bishop

Loma Linda University Electronic Theses, Dissertations & Projects

Periodontal regeneration and inflammation was evaluated histometrically in 36 paired teeth in six macque(sic) monkeys with chronic bifurcation defects. Daily topical TL Chlorhexidine was applied to one-half of the teeth, saline to the other half for six weeks after the bifurcation defects were surgically debrided. Measurements were made from a section taken from the mid-bifurcation for each tooth. The results demonstrated no significant difference in the area of inflammatory response or the degree of regenerative capacity of post-operative healing between Chlorhexidine treated and paired nontreated control teeth.

Effect Of Post-Operative Use Of Chlorhexidine On Regeneration Of Bifurcation Defects In Dogs, Gary Bogle

Loma Linda University Electronic Theses, Dissertations & Projects

The daily post-operative use of topical chlorhexidine application has been compared to daily toothbrushing. Periodontal defects were experimentally created in the bifurcations of lower premolars in dogs. The defects were treated by surgical debridement. Chlorhexidine application and toothbrushing were performed post-operatively for six weeks on contralateral pairs of teeth. The amounts of connective tissue and bone regeneration were evaluated from microscopic sections of the bifurcation areas. No difference between chlorhexidine and tooth brushing was found for the connective tissue attachment. However, significantly more bone had regenerated in the chlorhexidine treated areas than the tooth brushed area.

The Effects Of Crowding On The Diurnal Ascorbic Acid Levels Of Albino Rats, Mary Jo Barr

Masters Theses

The adrenal physiology of the albino rat was studied through the measurement of adrenal ascorbic acid levels. A cyclic phenomenon was observed which follows the diel periodicity of the animal. Ascorbic acid values were found to be characteristically higher in males than in females. A similar difference was also seen in populations divided into young animals (body weight less than 175 grams) and old animals (body weight greater than 175 grams). Crowding, induced by manipulating the area of cage space per gram of body weight, was observed to be a definite stressor and caused the adrenal ascorbic acid levels to …

The Effects Of Acute Stress On Adrenal Ascorbic Acid Levels, Robert Joseph Collier

Masters Theses

The diurnal rhythm of adrenal ascorbic acid (DAR) displays an inverse relationship to the diurnal rhythm of circulating levels of plasma corticosteroids. Alloxan monohydrate, 175 mg/kg body weight was given subcutaneously to albino rats to determine the effect of the diabetic state on the DAR. A total of 200 female albino rats were divided into two study groups. Study Group I was composed of 150 animals divided into populations of 15, each including 3 controls. Study Group II was composed of populations of 5, each group containing all controls or all alloxinated rats. The populations of 15 were sacrificed at …

Effects Of Dietary Factors And Morphine Administration On Voluntary Alcohol Consumption And Dopamine Metabolism In Rats, Claudia Smithson

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of diet and dietary additives on voluntary alcohol consumption in male Sprague-Dawley rats was studied. Alcohol intake measured weekly and reported as ml of a 10% solution ingested per 100 grams body weight. A four week pre-experimental period was designed to determine individual tendencies to drink and thus to eliminate the high and low drinkers from the study. No difference was found in alcohol intake with either starch or sugar as the carbohydrate source; however, there was a greater weight gain ( p < .025) in those animals consuming sugar-based diets. Rats on poor-quality diets containing minimal amounts of vitamins and minerals continued to gradually increase alcohol consumption during the study. This diet, supplemented with coffee, caused the greatest significant increase in alcohol intake and the lowest weight gains. Addition of coffee to the diets significantly increased alcohol consumption (p< .005) but decreased growth rate (p < .0005) . However, when the poor quality diets were supplemented with vitamins and minerals, alcohol consumption was reduced by about 50% (p < .005) and weight gain was significantly increased (p < .0005).

The daily intraperitoneal administration of morphine sulfate significantly decreased alcohol intake (p < .02) and the per cent of total fluid consumed as alcohol (p < .02) but did not effect water consumption.

An attempt was …

Microscopic Evaluation Of Topically Applied Chlorhexidine Gluconate On Gingival Wound Healing In Dogs, Robert C. Hirst

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate microscopically the effect of topically applied 2% chlorhexidine gluconate on the healing of gingival wounds in dogs.

One week after the teeth were scaled and polished, seven experimental wound sites were prepared in the facial gingiva adjacent to the four premolars on each side of the maxillary arch in six young Labrador dogs. From this point the dogs were fed a soft plaque-inducing diet. Chlorhexidine solution was applied daily to either the right or left maxillary premolars while on the opposite side of the arch in three dogs the first and second …

Marrow Isografts In The Oral Cavity Of Mice, Robert L. Merin

Loma Linda University Electronic Theses, Dissertations & Projects

The objectives of this study were to develop an animal model for testing oral bone and marrow transplantation that is adaptable to immunological studies; to determine the effect of an isogeneic graft of cancellous bone and marrow on the healing of surgically created defects; and to determine the fate of grafted isogeneic cancellous bone and marrow transplanted into defects. Fourteen CBA/H mice served as experimental animals and bilateral intraoral defects were prepared. The experimental side received isogeneic graft material while the other side served as a control. Osseous healing was found to be accelerated in the defects receiving graft material …

The Effect Of Oral Allografts Of Cancellous Bone And Marrow In Mice, George E. Deeb

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was: to develop a model for testing oral bone transplantation; to study the healing of a surgically produced defect with and without the transplantation of strongly allogeneic cancellous bones and marrow; and to determine the fate of the allogenic grafts. Twenty-eight CBA/H mice served as experimental animals. Intra-oral defects were made and in 14 of the animals strongly allogenic cancellous bone and marrow were transplanted. The 14 remaining animals served as controls. It was observed that the healing was delayed in the experimental animals as compared to the controls and that the grafted material was …

State-Dependent Learning As A Function Of The Temporal Relationship Between Noncontingent Footshock And Electroconvulsive Shock, T. Scott Shutt

All Master's Theses

Rats were given a noncontingent footshock followed at various intervals by electroconvulsive shock. Twentyfour hours later they were trained on a non-shock passive avoidance task and tested for retention 72 hours later. When the interval between NCFS and ECS was short the animals showed an amnesia which reduced as the interval was lengthened. An interval of .5 seconds produced the most pronounced amnesia and intervals greater than 10 seconds produced virtually no amnesia. The results were consistent with a state dependent retrieval failure hypothesis.

Root Exposure And Its Effect On The Fluid Movement Within The Tooth, William J. Busch

Loma Linda University Electronic Theses, Dissertations & Projects

This study examined the fluid movement in dentin associated with the exposure of the root surface for varying periods of time ranging from 75 minutes to 30 days. Eight kittens received experimental defects on the roots of the canines. Just prior to sacrifice a fluorescing dye was injected intraperitoneally to make the fluid within the dentin visible under ultraviolet light. Frozen ground sections were prepared and examined. The results showed that the exposed side of the root had a reduced amount of fluid fluorescence when compared to the opposite side of the tooth which had an intact root surface. The …

Cardioregulatory Role Of The Abdominal Ganglion Of Aplysia Californica, George Maeda

Loma Linda University Electronic Theses, Dissertations & Projects

An isolated heart-abdominal ganglion preparation of this mollusc was developed and used to study the cardioregulatory function of the ganglion and nerves. The heart was perfused with artificial sea water through an atrial cannula and the gastro-esophageal artery was catheterized for blood pressure monitoring. The presence and cardioregulatory effects of axons in the nerves was investigated by electrical stimulation. Fine-tipped glass microelectrodes inserted into ganglionic neurons were used to determine the relationship between the neuronal and cardiac activities.

The principal results are listed below.

1. Primarily inhibitory responses are obtained from both right and left connective stimulation, with some evidence for …

Sub-Aversive Response Contingent Foot Shock As A Positive Reinforcer, Robert Lea Fulwiler

All Master's Theses

Forty-eight rats were divided into 8 groups; four were maintained under normal conditions and the other four under sensory deprivation and tested at o, 3, 6, and 9 days after condition institution. The response was placing the head through a hole in the operant chamber and the stimulus (0, 1.2, 4, or 12 Vac) was contingent upon the response. Analysis ot variance disclosed significant differences (p<.01) between the deprived and the non-deprived groups at days 6 and 9; and a significant interaction between deprivation condition and time of test. No differences were shown between the stimulus intensities indicating that the stimulus did not have a reinforcing effect.

The Effect Of Elevated Glucose On Neutrophilic Phagocytosis In Genetically Diabetic Mice, Larry B. Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

Infiltration to an injury site or area of bacterial contamination by polymorphonuclear leucocytes (or neutrophils) is an early and essential phase of the early inflammatory reaction. Their action on foreign matter is the most critical step taken by body defense mechanisms in the first 24 hours. Anything which interferes with that action, phagocytosis, greatly hampers early inflammation. This study was designed to see the effect of elevated glucose levels on neutrophil phagocytosis in a unique strain of genetically diabetic mice.

Twenty-two diabetic and twenty-four control female mice were used. Blood glucose determinations and total white counts were made on each …

The Response Of Gingival Tissues To Alterations In Ph, Robert C. Jann

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the histopathological and clinical changes that occurred when a continuous supply of exogenous acid or base, at varying pH, was delivered adjacent to the gingival crest of the monkey. A related goal was to develop a monkey model system which would deliver test solutions continuously and atraumatically, to the experimental gingival sites.

Two young adult female monkeys had a perfusion apparatus attached to certain maxillary teeth so that test solutions were deposited atraumatically to the marginal gingival tissues. During the experimental periods the animals were kept in primate restraining chairs and fed …

The Effects Of Cs Habituation And Duration Of The Directional Modification Of The Cardiac Response In The Guinea Pig (Cavia Procellus), Ray Charles Larson

All Master's Theses

The present experiment examined the effects of CS habituation and two different levels of CS duration (60 versus 6 sec) on the directional modification of the conditioned cardiac response in the guinea pig. The results indicated that the only reaction to the CS, regardless of prior habituation or CS duration, was a decelerative conditioned HR response. However, habituation to a CS prior to classical aversive conditioning was found to attenuate the magnitude of the bradycardia CR that developed. The bradycardia CR was discussed in terms of being a cardiac component of the orienting response.

An In Vivo Perfusion Apparatus For Studies On Gingival Disease In The Albino Rat : Assessment By A Perfusion Of The Enzymes Collagenase And Hyaluronidase, James A. Smith

Loma Linda University Electronic Theses, Dissertations & Projects

This thesis describes an in vivo perfusion apparatus which can continuously deliver controlled quantities of solutions to localized, contralateral intraoral areas in albino rats. Three animals were per fused on the experimental area (the mesial sulcular area of the maxillary first molar) on one side with tap water and Trypan blue. Localization of the solution delivered and minimal histological changes due to the presence of the apparatus was demonstrated on these animals. Solutions of .5%, 1%, and 2% hyaluronidase and collagenase were perfused on the experimental areas of nine animals. When both enzymes were used, hyaluronidase always preceded collagenase in …

A Study To Demonstrate The Immediate Destination Of An Embolus Formed In The Lumen Of A Peripheral Venous Catheter, Rosemarie Morikone Emori

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to show the immediate destination of an embolus formed in the lumen of an intravenous catheter placed in a peripheral vessel. The hypothesis stated that clots injected into a peripheral vessel will lodge in the lungs. A subhypothesis was that the clot may lodge anywhere along the circulatory pathway.

Indications of need for the study as shown by the review of literature were the following: (1) the complications resulting from the frequent use of intravenous polyethylene catheters, (2) experimental studies that showed that clots were formed around intravenous catheters, (3) the evidence that intravenous catheters predispose …

Effects Of Diet And Stress On Gastric Lesions In Albino Rats And Guinea Pigs, Naomi Mckenzie

Loma Linda University Electronic Theses, Dissertations & Projects

Studies were conducted to (1) investigate whether any protective factor is present in fresh water-cured olives or fresh cabbage as compared with the heated supplements against stress-induced gastric lesions in rats maintained on a nutritionally adequate diet for six weeks, (2) determine the relative protective factor in water-cured olives as compared with cabbage, (3) study the effect of black pepper in combination with fresh cabbage and olives and heated cabbage and olives in rats that were fed the same nutritionally adequate diet, and (4) investigate the effects of the same dietary components—cabbage and olives--on histamine- induced gastric lesions in guinea …

Mandibular Nerve Regeneration Through Solid And Canalized Bone And Plaster Grafts, Lawrence D. Day

Loma Linda University Electronic Theses, Dissertations & Projects

Utilizing an extra-oral approach and sterile technique, left mandibular ostectomy was performed on five miniature pigs. The segment removed was 3 cm long and included the inferior border, mandibular canal and, in some cases, apices of a molar tooth.

Bone and plaster grafts (one solid and one canalized of each) were used to fill these defects. The fifth was left with no graft.

The objective was to learn the effect of each of these procedures on regeneration of the mandibular nerve across the defect. It was hypothesized that canals through the grafts would facilitate regeneration.

X-rays were taken periodically. The …

Some Aspects Of Cranial Bone Growth In The Puberal Macaca Mulatta Monkey: As Evidenced By Metallic Implants And Cephalometric Roentgenography And The Application Of A Geological Lapidary Technique For The Semi-Serial Thin Sectioning Of Undecalcified Bone, Lee Eugene Olsen

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to investigate cranial and facial bone growth in the puberal Macaca mulatta monkey over a six month period utilizing the methods of metallic implantation combined with serial cephalometric roentgenography and a bichromatic vital staining method.

The employment of the vital stains, alizarin Red S and anthracene blue, over the six month period of the study, failed to stain the actively growing bone as evidenced by gross and microscopic analysis of the undecalcified bone preparations.

Interimplant measurements were made across certain bone sutures and the following results were obtained: The zygomaticotemporal sutures showed marked growth …

The Effect Of Removing The Crevicular Epithelium Upon Canine Tooth Replantation, Leon A. Leonard

Loma Linda University Electronic Theses, Dissertations & Projects

The nature of epithelium and the remarkable facility with which it aggressively covers granulation tissue, suggests that removal of the sulcular epithelium surrounding the extraction wound of a tooth to be replanted could promote reattachment of the periodontal tissues at a more nearly ideal coronal level. To investigate this hypothesis twenty mature teeth in five mongrel dogs were experimentally replanted. One half of them were replanted in alveoli around which the crevicular epithelium had been removed, the remaining teeth without creviculoectomy acting as controls. Animals were euthanized at one, two, three, five, and sixteen weeks. After clinical evaluation of the …

A Cephalometric, Anatomic And Histologic Investigation Of The Effects Resulting From A Heavy Interrupted Orthopedic Force To The Maxilla Of The Macaca Mulatta Monkey, Roger Wayne Triftshauser

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine changes that occur in the craniofacial complex, when a heavy interrupted orthopedic force is employed to retract the maxilla in the post puberal rhesus monkey. Cephalometric, histologic and anatomic examinations were utilized to substantiate the findings.

Four female rhesus monkeys were used for experimentation. Two were experimental animals and the other two controls. Cervical retraction with headgear was applied over a period of 313 days and 159 days to the two experimental animals. Forces not exceeding 2.5 lbs. were found most effective.

The findings were as follows:-

1. A total posterior displacement of …

Protection For Animals In Biomedical Research, F. L. Thomsen

Laboratory Experiments Collection

Our conclusion from all of this work and study is that not just a small part, but that most of the suffering undergone by laboratory animals in "unnecessary" under the terms of the pain provisions of the Rogers-Javits bill. Granted, it will take some time and effort to bring about the necessary interpretations of these provisions. The Act, when passed, offers us the medium through which to obtain such interpretations.

This unnecessary suffering results mostly from the indifference, and from the inertia and the lack of proper scientific training and technical knowledge, of many of those conducting laboratory animal experiments …

Pig Husbandry Research In Western Australia, N W. Godfrey

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

IN the past it has not been possible to undertake research work with pigs on any appreciable scale in Western Australia.

A small herd has been maintained at Denmark Research Station for some years as a demonstration side-line unit, run in conjunction with the dairy herd.

A number of very useful trials have been carried out with the Denmark herd, but its size has limited the comprehensiveness of the type of research work that could be undertaken.

The Transfer Of Hydrogen In The Reduction Of Progesterone, William H. Kersey

Loma Linda University Electronic Theses, Dissertations & Projects

Experimental female rats were given daily injections of synthetic estrogens for six months. The effect on rat ovarian 20α-OH-SDH was not definitive. Diethylstilbestrol and 17α-ethynylestradiol caused a significant drop in activity as compared with controls while mestranol caused a slight increase in activity. A synthetic progestin, medroxyprogesterone, had no apparent effect on the activity of the enzyme.

Rat ovarian 20α-OH-SDH was purified fivefold by ammonium sulfate fractionation and chromatography on DEAE-cellulose.

The homogeneity of the enzyme was checked by means of disc gel electrophoresis. At pH 8.2 no significant contamination appeared in the electrophoretic pattern, but at pH 9.0 five …

Craniofacial Changes Resulting From Expansion Of The Midpalatal Suture In The Macaca Mulatta Monkey As Revealed By Roentgenographic Analysis, Raymond M. Sugiyama

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the effects of midpalatal suture separation on the craniofacial complex by quantitative roentgenographic analysis.

Ten female Macaca mulatta monkeys were randomly grouped for experimentation. Six animals were paired in groups for two months of treatment, four months of treatment followed by two months of post retention, and six months of treatment. The four remaining monkeys were paired and served as control animals for two and six month periods. Total activation of the expansion appliances in the treated animals was completed over a three week period.

The findings of this study were based …

Forced Separation And Consequent Stability Of The Midpalatal Suture Of The Macaca Mulatta Monkey, Frederick L. Hoffer Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to (1) demonstrate the dimensional changes resulting from opening the suture, (2) test the stability of the repaired suture two months following the removal of the retentive appliance, and (3) demonstrate new bone growth in the opened suture by the use of Tetracycline staining. The animal chosen was the Macaca mulatta monkey.

Intact skulls, sectioned skulls and dental casts were measured following the experiment. The skulls were mounted in clear plastic and sectioned antero-posteriorly for the purposes of study and measurements. The following changes were noted as a result of this experiment:

1. The floor of the …