Research Methods in Life Sciences Commons^™

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 …

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 …

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 …

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 …

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 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 …

Oral Bandage Tissue Reaction In Dogs, John Rozema

Loma Linda University Electronic Theses, Dissertations & Projects

This experiment was designed to evaluate an oral surgical dressing which may be used as an aid to healing tissue. The parameters of evaluation were directed toward wound healing enhancement, duration, and stability of the bandage. A histological evaluation of the surgical wounds protected with the bandage as compared to the control wounds was made.

The surgeries were performed on eight dogs in a double controlled experiment and were in the form of bilateral maxillary gingivectomies and mandibular molar tooth extractions. The surgery sites on the left were covered with the Orahesive Bandage while the right side remained exposed to …

Effects Of Poor Quality Diets With Various Dietary Factors Added And Exposure To Cigarette Smoke On The Voluntary Alcohol Intakes Of Albino Rats, Bonnie Emmerson

Loma Linda University Electronic Theses, Dissertations & Projects

Studies were conducted utilizing albino rats to determine the relationship of voluntary alcohol consumption with various dietary additives and exposure to cigarette smoke in combination with poor quality diets. Male, Sprague-Dawley rats, from weanling age to 100 grams, were given the various experimental diets and a free fluid choice of ten per cent ethanol or tap water. Fluid intakes were recorded and analyzed statistically. Individual variation was common with a generally low level of alcohol consumption when rats were fed a poor quality diet of common United States foods. The addition of caffeinated beverages and/or spices and relish caused increases …

Carbon Dioxide Fixation In Schistosoma Mansoni, Clint Earl Carter

Loma Linda University Electronic Theses, Dissertations & Projects

Adults of the blood fluke Schistosoma mansoni were perfused from the hepatic portal system of CF1 female mice sixty to seventy days post infection. The worms were then incubated in Eagle’s minimal essential medium with glutamate and 0.03 mg/100 ml of nonlabelled aspartic acid. To this medium was added 10 μc of either NaH¹⁴0₃, glucose-UC¹⁴ or aspartate-4-C¹⁴. The worms were found to fix carbon from the NaH¹⁴0₃ and to incorporate the glucose and aspartate. The amount of activity recovered in five different chemical fractions after two hours incubation was determined …

Mandibular And Alveolar Growth In Dog Following Infusion Of 5-Fluorouricil, Richard D. Pfeiffer

Loma Linda University Electronic Theses, Dissertations & Projects

The action of a chemotherapeutic agent as a tool in studying its effect upon a primary growth center, the mandibular condyle, was investigated. So far as can be ascertained, no studies have been reported where these growth sites have been eliminated or modified by the use of chemotherapeutic growth inhibitors.

Observation of mandibular and alveolar growth following the infusion into the left external carotid artery of a cancer chemotherapeutic agent, 5-Fluorouricil (Roach-Hoffman), was noted. Comparisons were made between the infused and the uninfused sides of the mandible observing gross growth changes.

Four dogs, aged 75 days, were infused with varying …

The Effect Of Schistosoma Mansoni On Free Amino Acid Levels In Mice, Richard D. Tkachuck

Loma Linda University Electronic Theses, Dissertations & Projects

Free amino acid levels in the blood plasma of mice infected with Schistosoma mansoni Sambon, 1907, were measured at 3, 6, and 9 weeks post-infection with an automatic amino acid analyzer. Significant differences between experimental and control animals occurred at all three time periods. At 3 weeks, asparagine, alanine, citrulline, proline, methionine, and threonine levels all were lower in the infected animals. At 6 weeks, four differences were noted. Alpha-amino-n-butyric acid, ornithine, lysine, and histidine all had lower values in infected animals. At 9 weeks there were 12 differences. Tyrosine, phenylalanine, threonine, serine, proline, citrulline, glycine, alanine, valine, isoleucine, and …

The Fecal Shedding Of Listeria Monocytogenes By Conventional And "Germ Free" Mice, Margaret Joyce Ramsay

Loma Linda University Electronic Theses, Dissertations & Projects

A series of experiments involving Listeria monocytogenes was undertaken to study first the fecal shedding of Listeria by conventional mice challenged intraperitoneally with Listeria and second the fecal shedding and ability to survive of germ free mice with similar challenge. In addition, mites infesting Listeria infected mice were cultured for their possible contamination by Listeria.

Conventional mice were challenged intraperitoneally with a single near LD₅₀ dose of Listeria. Fecal Listeria were detected by collecting specimens from each mouse daily for the first 4 days and every second day thereafter. The feces was held at 7°C for 14 …

Antibiotics And The Wasting Disease In Neonatally Thymectomized Rats, Douglas M. Grignon

Loma Linda University Electronic Theses, Dissertations & Projects

The administration of the antibiotic, Chloramphenicol, to pregnant rats just prior to, and for four days after delivery, diminishes the incidence of the so-called "Wasting Disease" in neonatally thymectomized rats.

A total of 50 rats were divided into the following groups:

1. Thymectomy only---nonmedicated 17 rats
2. Thymectomy only---medicated 12 rats
3. Thymectomy-adrenalectomy---nonmedicated 5 rats
4. Thymectomy-adrenalectomy---medicated 8 rats
5. Controls---nonmedicated 4 rats
6. Controls---medicated 4 rats

Chloramphenicol was administered in the drinking water to the mothers of groups 2, 4 and 6 for about 2 days prior to delivery and 4 days after. On the day of birth or within three days after birth, the …

The Effect Of Varying Protein Intake On Trichinella Spiralis Infection In Mice, Clare K. Kwan

Loma Linda University Electronic Theses, Dissertations & Projects

Three hundred Swiss Webster albino mice three weeks of age were placed on low (8%), medium (24%), high (48%) protein levels and a commercial laboratory animal feed, Purina Chow for various lengths of time: (1) simultaneously with infection, and four weeks thereafter, (2) three weeks before infection and throughout the four-week infection period, and (3) six weeks prior to infection and during the infection period. The protein source was casein. Sixty of the 300 mice used served as noninfected controls, and the other 240 were each infected with 400 washed, suspended Trichinella spiralis larvae obtained from a rat by the …

A Study Of Regeneration Of Peripheral Nerve In The Rat, James C. Jay

Loma Linda University Electronic Theses, Dissertations & Projects

Due to improvements in fixation and embedding techniques a restudy of regenerating peripheral nerve was thought advisable in order to better understand and describe the processes which take place.

Femoral nerves of white Wistar rats were used. The lesions were made by either crushing or severing the nerve. After a period of regeneration, varying from 12 hours to six days, the wound was reopened and the injured portion fixed in situ with 1% osmium tetroxide. The tissues were then removed, dehydrated, embedded and sectioned. The sections were stained and studied with a modified RCA EMU2A electron microscope.

Observations revealed that …

Pharmacological Studies Of Antidiabetic Chinese Herbs, Mun Fa Lee

Loma Linda University Electronic Theses, Dissertations & Projects

Rehmannia glutinosa, Atractylus ovata, and Polygonatum chinense have all been employed by the Chinese as oral antidiabetic agents and reported by Min (1928), Kin (1931), and Li et al. (1936) to possess hypoglycemic activity. This prompted the pharmacological studies of these herbs.

Materials and methods. Their pharmacognosy was condensed from all available Chinese and scientific literature. Preliminary chemical and physical analyses included determinations for moisture, ash, crude fat, carbohydrates, protein, phosphorus, pH, alkaloids, melting point, and spectroscopy. Employing the Somogyi-Nelson method, their glycemic activity was studied in rats, rabbits, and dogs. Stress reactions were minimized. The effect …

The Effect Of Preweanling Administration Of Carbohydrates Used In Infant Formulas On Subsequent Dental Caries In White Rats, Erlinda Amor Romulo

Loma Linda University Electronic Theses, Dissertations & Projects

The high incidence of tooth decay, one of the most common diseases found in all age groups, gives a reason for the study of methods to prevent dental caries. Certain dietary factors, specifically carbohydrates, have been implicated in the decay process. Since diet influences both the oral and systemic environments in which the teeth develop, mature, age, and decay (1), many studies have been conducted to determine the effects of oral administration of different carbohydrates on dental caries. The extrinsic effects of diet on the mature erupted tooth have, however, been the major concern of the research (2).

The first …