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Transcriptional Regulation Of Insulin-Like Growth Factor : Binding Protein-4 By Protein Kinase A And Protein Kinase C Signal Transduction Pathways In Human Bone Cells, Kuk-Wha Lee Dec 1994

Transcriptional Regulation Of Insulin-Like Growth Factor : Binding Protein-4 By Protein Kinase A And Protein Kinase C Signal Transduction Pathways In Human Bone Cells, Kuk-Wha Lee

Loma Linda University Electronic Theses, Dissertations & Projects

The Insulin-like Growth Factor (IGF) system is an important local regulator of osteoblast proliferation, the primary determinant of bone formation. Six IGF Binding Proteins (IGFBPs) either inhibit or enhance IGF actions. Previous studies have shown that IGFBP-4 is an important negative regulator of osteoblast cell proliferation and that agents such as PTH which increase intracellular cAMP significantly increase expression of IGFBP-4 at the protein and mRNA levels. The underlying molecular mechanism which accounted for IGFBP-4 expression had not been determined and was the focus of my dissertation. Agents which increase intracellular cAMP rapidly increased IGFBP-4 mRNA levels. Nuclear run-off experiments …


A Pilot Study Comparing The Forces Applied : Using A Chin Cup And Three Types Of Protraction Headgear, Daniel Miles Beisiegel Dec 1994

A Pilot Study Comparing The Forces Applied : Using A Chin Cup And Three Types Of Protraction Headgear, Daniel Miles Beisiegel

Loma Linda University Electronic Theses, Dissertations & Projects

A pilot study comparing force distributions of a chin cup, the Great Lakes reverse pull headgear (RPHG), Ormco's adjustable dynamic RPHG, and Grummons RPHG was done. A skull from a 69 year old female which demonstrated a Class III malocclusion was used to perform the tests of force. Forces applied to and generated on the skull were measured using a water-filled balloon system. This method was tested and found to be reliable and accurate.

Repeated measurements of force were recorded for each of the areas of stress (forehead, cheeks, chin, and condyles, as well as the posterior and superior portions …


Stab Wounds To Rat Brains : Demyelination, Remyelination And The Cellular Response, Particularly Of Oligodendrocytes, Xie Dangci Aug 1994

Stab Wounds To Rat Brains : Demyelination, Remyelination And The Cellular Response, Particularly Of Oligodendrocytes, Xie Dangci

Loma Linda University Electronic Theses, Dissertations & Projects

The present body of knowledge concerning the results of central nervous system injury is incomplete and controversial. The role of oligodendrocytes, the cells involved in phagocytosis, the stages of demyelination, and the evidence for remyelination are of interest. Following stab wounds to rat brain cortex, corpus callosum and hippocampus, the animals were examined at 4,7,11,18,23,29,45,60 and 70 days postoperation (dpo). To help in the identification of cells immunocytochemical markers for astrocytes and immature oligodendrocytes were used. These were labels for glial fibrillary acidic protein (GFAP) and myelin/oligodendrocyte specific protein (MOSP) respectively. Light and electron microscopy were correlated using conventionally prepared …


The Relationship Of Dietary And Lifestyle Factors To Bone Mineral Density Of Healthy Singaporean Chinese Women, Ampai Dana Aimsiri Aug 1994

The Relationship Of Dietary And Lifestyle Factors To Bone Mineral Density Of Healthy Singaporean Chinese Women, Ampai Dana Aimsiri

Loma Linda University Electronic Theses, Dissertations & Projects

Few studies have examined the risk factors associated with reduced bone mass in Asians, but none specifically investigated Singaporean Chinese women. The subjects in this study were 16 premenopausal, 8 perimenopausal and 13 postmenopausal women who participated in a larger study which began in 1986. Bone density was measured in 1986 and 1992. Dietary and lifestyle data were collected for this study by personal interview. Association between dietary and lifestyle factors and bone density variables and change in bone density at the end of the 6 year period were assessed by univariate regression analyses.

Postmenopausal women had significantly lower baseline …


Effects Of Furosemide And Oleic Acid On Thyroxine Binding To Isolated Pairs Of Thyroxine Binding Serum Proteins, Deborah Hustead Aug 1994

Effects Of Furosemide And Oleic Acid On Thyroxine Binding To Isolated Pairs Of Thyroxine Binding Serum Proteins, Deborah Hustead

Loma Linda University Electronic Theses, Dissertations & Projects

Dosage dependent binding inhibition and redistribution of thyroxine (T4) between three pairs of thyroxine binding serum proteins, TBG-TTR, TBG-albumin and TTR-albumin, by furosemide (0.0 to 1.0 mol/L) and oleic acid (0.0 to 0.10 mol/L) were studied using equilibrium dialysis with purified binding proteins at concentrations 1/200 of levels in normal human sera, separated across the dialysis membrane and competing for T4.

Furosemide (1.0 mol/L) reduced TBG bound T4 in both the TBG-TTR system and TBG-albumin system (>90% decrease) and inhibited T4 binding to TTR in the TTR-albumin system (68% decrease) and to albumin …


The Production And Characterization Of A Monoclonal Antibody To A Naturally Occurring Aminomalonic Acid Epitope And A Comparison With An Antibody To A Synthetically Derived Aminomalonic Acid Epitope, James L. Gulley Aug 1994

The Production And Characterization Of A Monoclonal Antibody To A Naturally Occurring Aminomalonic Acid Epitope And A Comparison With An Antibody To A Synthetically Derived Aminomalonic Acid Epitope, James L. Gulley

Loma Linda University Electronic Theses, Dissertations & Projects

The goal for this project is to undertake the first step in the study of blocking metastasis by a monoclonal antibody. The long range goal of this line of research is to study a novel mechanism for the blocking of tumor metastasis in general and prostatic cancer metastasis in particular. The problem that this addresses is the growing number of cases of prostatic cancer in the increasingly aging male population. This cancer is not lethal unless it metastasizes, yet there is no cure for the metastatic disease. The inherent specificity of a monoclonal antibody combined with the uniqueness of the …


Short And Long Term Effects Of Proton Microbeam Irradiation : In The Lateral Geniculate Nucleus Of Felis Domesticus, Chad Sherwood Reder Aug 1994

Short And Long Term Effects Of Proton Microbeam Irradiation : In The Lateral Geniculate Nucleus Of Felis Domesticus, Chad Sherwood Reder

Loma Linda University Electronic Theses, Dissertations & Projects

Little is known of the effects of proton irradiation on neural tissue. A 1.0 mm microbeam was used on the cat lateral geniculate nucleus (LGN) to quantify the short term (< 3 months) and long term (< 9 months) effects of radiation damage. The LGN is a large structure with well defined afferent, efferent, and receptive field properties.

Electrophysiological and histological techniques were used to examine the effects of the microbeam at 60, 40, and 16 Gy, administered as a single bolus. Recordings of light evoked responses in the LGN were obtained using microelectrodes in nine animals within 12 weeks of irradiation, and 6 animals within 36 weeks of irradiation. Receptive fields were mapped onto a tangent screen using standard receptive field techniques. Histological measures included afferent …


Cerebral Microcirculatory Effects Of Maturation, Scott R. Elliott Jun 1994

Cerebral Microcirculatory Effects Of Maturation, Scott R. Elliott

Loma Linda University Electronic Theses, Dissertations & Projects

The present studies demonstrate that in the second (2B) and fourth (4B) branches of newborn and adult sheep middle cerebral arteries, 5-HT2 serotonergic receptors mediate contractile responses to serotonin and that alpha-1 adrenergic receptors mediate contractile responses to norepinephrine. In addition, tissue sensitivity to 5-HT and NE decreases significantly with maturation, but does not vary with branch order. These age-related changes were associated with a decrease in affinity and maximum response in 2B and 4B segments of 5-HT and NE contracted arteries, respectively. Norepinephrine and 5-HT occupancy at the pD2 rose significantly in 2B segments, but did not change …


Healing Potential Of Osteotomies Of The Nasal Sinus In The Dog, Roderick W. Tataryn Jun 1994

Healing Potential Of Osteotomies Of The Nasal Sinus In The Dog, Roderick W. Tataryn

Loma Linda University Electronic Theses, Dissertations & Projects

Maxillary sinus osteotomy is sometimes indicated for transantral surgical approaches to palatal roots of maxillary molars. A search of the literature showed an absence of any report on the healing potential of such defects. The purpose of this study was to determine histologically the reparative process of the nasal sinus of dogs following small and large surgical antral perforations. After anesthetizing six beagle dogs, full thickness periosteal flaps were raised overlying the maxillary buccal cortical plates. A 5x5 mm diameter perforation was created with a trephine bur above the second maxillary premolar on one side of each animal. On the …


Measurement Of Blood Flow In Reflected Muco-Gingival Tissue Flaps In Cats : Using The Radiolabeled Microsphere Method, Gary T. Wuchenrich Jun 1994

Measurement Of Blood Flow In Reflected Muco-Gingival Tissue Flaps In Cats : Using The Radiolabeled Microsphere Method, Gary T. Wuchenrich

Loma Linda University Electronic Theses, Dissertations & Projects

Blood flow to the maxilla and mandible may vary due to differences in vascular supply and in physiologic, metabolic and pathologic conditions. In general it is accepted that oral tissues have an abundant blood supply; however, there is little information quantifying blood flow to these regions. In this study, the maxillary tissues were chosen to measure the blood flow in attached and reflected gingival tissue in adult cats using the radiolabeled microsphere method.

Sixteen cats with permanent dentition, clean mouths, and without inflamed gingiva upon visual inspection were used and divided into two groups. Group 1 consisted of six cats …


Load Deformation Test Of Mini Twin Metal Brackets : A Comparative Study, Karl D. Peach Jun 1994

Load Deformation Test Of Mini Twin Metal Brackets : A Comparative Study, Karl D. Peach

Loma Linda University Electronic Theses, Dissertations & Projects

The trend toward more esthetic brackets has led to smaller brackets being used by orthodontists. The purpose of this study was to determine the force required to deform these smaller brackets and calculate the stress in the metal by using a torsional wire bending force. Ten types of brackets were tested and the results analyzed to determine how bracket geometry, manufacturing method, or material selection affected the strength of brackets. Results showed a significant difference between manufacturing methods, material used, and bracket geometry. Brackets made of 17-4 PH SS and 303 SS withstood higher stress than 316 SS, and all …


Healing Following Periodontal Reconstructive Surgery : Surgical Implantation Of A Collagen Matrix Or Demineralized Freeze-Dried Bone Allograft, Seong Yong Choi Jun 1994

Healing Following Periodontal Reconstructive Surgery : Surgical Implantation Of A Collagen Matrix Or Demineralized Freeze-Dried Bone Allograft, Seong Yong Choi

Loma Linda University Electronic Theses, Dissertations & Projects

Healing following periodontal reconstructive surgery including surgical implantation of a collagen matrix or demineralized freeze-dried bone allograft (DFDBA) was evaluated in a preclinical (collagen) and a clinical (DFDB A) study.

Contralateral periodontal fenestration defects in 7 beagle dogs were used to evaluate the effect of a collagen matrix on periodontal healing. The defects (6x4 mm) were created through the buccal cortical plates of the maxillary canine teeth following elevation of mucoperiosteal flaps. The collagen was fitted to the defects on one side, while contralateral defects served as controls. Raps were repositioned and sutured. Dogs were sacrificed 4 weeks after surgery …


An In Vitro Quantitative Evaluation And Comparison Of A Custom And A Popular Stock Orthodontic Appliance, Richard Scott Anderw Schalo Jun 1994

An In Vitro Quantitative Evaluation And Comparison Of A Custom And A Popular Stock Orthodontic Appliance, Richard Scott Anderw Schalo

Loma Linda University Electronic Theses, Dissertations & Projects

An in vitro performance evaluation and comparison of a patient individualized appliance (Elan, Ormco Corporation, Glendora, California) and a Roth prescription appliance ("A"- Company, San Diego, California) was made using the Ideal Tooth Relationship Index (ITRI).

The sample consisted of 19 duplicated sets of models for a total sample of 38. For each pair of models one set was bonded with an Elan appliance and a duplicated set was bonded with a Roth appliance. Bracket placement followed the manufacturers recommendations. The bracketed teeth from these models were sectioned out individually and the appliances allowed to fully express themselves on full …


Long-Term Posttreatment Upper Incisor Inclination : Relative To Facial Axis Angulation As A Measure For Incisor Placement, David Lawrence Sparks Jun 1994

Long-Term Posttreatment Upper Incisor Inclination : Relative To Facial Axis Angulation As A Measure For Incisor Placement, David Lawrence Sparks

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to determine whether upper central incisor inclination approximated the facial axis, long-term, posttreatment, regardless of the initial malocclusion or immediate posttreatment incisor inclination. Lateral head films at pretreatment, immediate posttreatment and long-term posttreatment were traced and evaluated. The sample was divided into facial type. Angle classification and treatment type (extraction vs. non-extraction). Statistical analyses included means, standard deviations, confidence intervals, population t tests and chi-square tabulations.

The results revealed that the upper central incisor did not approximate the facial axis after a minimum of 7 years posttreatment. This failed to support the use of the facial …


An Assessment Of Three Different Forms Of Sterlization And Clinical Usage On Various Orthodontic Pin And Ligature Cutters : A Pilot Study, Warren L. Creed Jun 1994

An Assessment Of Three Different Forms Of Sterlization And Clinical Usage On Various Orthodontic Pin And Ligature Cutters : A Pilot Study, Warren L. Creed

Loma Linda University Electronic Theses, Dissertations & Projects

With an awareness of cross infection in dentistry and of AIDS (acquired immune deficiency syndrome), sterilization in the dental office has been brought to the public's attention by the news media. Much work has been done on which sterilization methods are acceptable but little has been written about the effects of sterilization procedures on the instruments themselves. In this study, 36 pin and ligature cutters were sterilized 250 cycles using three different methods of sterilization following the guidelines given by the Center for Disease Control (CDC). The cutters were examined for changes in lateral hinge movement, visual appearance and ordinal …


Periodontal Repair In Dogs : Part I : Evaluation Of The Natural Disease Model ; Part Ii : Eptfe Barrier Membranes Support Wound Stabilization And Enhance Bone Regeneration, James Marc Haney Jun 1994

Periodontal Repair In Dogs : Part I : Evaluation Of The Natural Disease Model ; Part Ii : Eptfe Barrier Membranes Support Wound Stabilization And Enhance Bone Regeneration, James Marc Haney

Loma Linda University Electronic Theses, Dissertations & Projects

Animal models are frequently consulted for histometric analysis of reconstructive periodontal therapy. Statistical analysis of induced lesion defects and surgically created defects from our laboratory suggest defect size homogeneity is critical for the model to discriminate treatment effects. This study characterizes natural disease defects in beagle dogs. Buccal-lingual histologic sections from the 2nd, 3rd, and 4th mandibular premolar teeth (P2, P3, P4) from 6 aged beagle dogs with natural disease defects were evaluated for variation in defect height between pair matched tooth types, and jaw quadrants, as well as estimated confidence intervals for treatment differences between left and right pair …


Signal Transduction In Bacterial Chemotaxis, Edward Heath Rowsell Jun 1994

Signal Transduction In Bacterial Chemotaxis, Edward Heath Rowsell

Loma Linda University Electronic Theses, Dissertations & Projects

This study investigated the site of ATP utilization in the signal transduction pathway of bacterial chemotaxis and localized the point of convergence of a methylation-independent system of chemotaxis with the methylation-dependent system. The identity of the signal originating from the phosphotransferase system was investigated by substituting the fructose-inducible HPr-like protein FPr for HPr in transport and chemotaxis. In addition, a novel chemoattractant, glycerol, was identified for Salmonella typhimurium. Histidine-auxotrophic S. typhimurium strains ST23 (hisF) and ST171 (hisF cheB) were depleted for ATP. The times required for the bacteria to adapt to a step increase in serine, …


Identification Of Risk Factors Associated With Pulpal Disease, Shelley R. Aronson Jun 1994

Identification Of Risk Factors Associated With Pulpal Disease, Shelley R. Aronson

Loma Linda University Electronic Theses, Dissertations & Projects

A few studies have identified etiologic factors in pulpal disease, but little is known about the odds ratios of factors associated with pulpal disease. Odds ratios are well established measures of the effects of exposure to a particular outcome, and are comparisons of exposure to non-exposure in cases versus controls. The purpose of this study was to compare exposure of individual teeth to hypothesized risk factors in endodontic cases and in controls. This case-control study consisted of a chart review of 301 endodontic cases and 301 controls. Caries, types of restorations, and periodontal disease were the most significant factors. With …


The Influence Of Prepregnancy Weight And Maternal Weight Gain : On Birth Weight Among Black Wic Participants In San Bernardino County, Marta Lukas Sovyanhadi Jun 1994

The Influence Of Prepregnancy Weight And Maternal Weight Gain : On Birth Weight Among Black Wic Participants In San Bernardino County, Marta Lukas Sovyanhadi

Loma Linda University Electronic Theses, Dissertations & Projects

Birth records show that San Bernardino County has the highest black infant mortality rate of the 16 counties in California with the largest proportion of African-Americans births. Although total infant deaths in San Bernardino County had fallen to 8.6 per 1,000 live births by 1992, the infant mortality rate among the black population of the county was close to two times higher at 16.8 per 1,000. This is the first study to address the high infant mortality rate among blacks in San Bernardino County. Factors which may affect the black infant mortality rate were examined.

Subjects were drawn from a …


A Physical Map Of The Klebsiella Pneumoniae M5a1 Genome, Alexandrine Randriamahefa Mar 1994

A Physical Map Of The Klebsiella Pneumoniae M5a1 Genome, Alexandrine Randriamahefa

Loma Linda University Electronic Theses, Dissertations & Projects

Klebsiella pneumoniae is an enteric opportunistic pathogen which commonly causes pulmonary, urinary tract and kidney infections. It has also been widely used for the study of nitrogen fixation. In this study, a macrorestriction map of K. pneumoniae M5a1 chromosomal DNA was constructed using pulsed field gel electrophoresis (PFGE) and Southern hybridization techniques. The genome DNA was digested with two rare cutting restriction enzymes (XbaI and BlnI) and the genome size was estimated from the sum of the fragment sizes as 5,121 Kb (+2.8%). A tentative order of fragments was deduced using Southern hybridization with purified restriction fragments. …