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Quantitation of Endogenous Nucleotide Pools in Pseudomonas aeruginosa

Nucleotide pools were extracted and quantified from Pyr^+ and Pyr^- strains of P. aerucjinosa. Strains were grown in succinate minimal medium with and without pyrimidines, and nucleotides were extracted using trichloracetic acid (TCA; 6% w/v). The pyrimidine requirement was satisfied by uracil, uridine, cytosine or cytidine. Pyr^- mutants were starved for pyrimidines for two hours before nucleotide levels were measured. This starvation depleted the nucleotide pools which were restored to wild t… more

Date: August 1988

Creator: Entezampour, Mohammad

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

The Evolution, Applications, and Statistical Interpretations of DNA Typing in Forensic Science

This thesis examines the evolution, applications, and statistical interpretations of DNA typing as a tool in the field of forensic science as well as in our criminal justice system. The most controversial aspect of DNA typing involves the determination of how likely it is that two people share the same DNA profile. This involves the use of population genetics and databases of allelic frequencies as well as some assumptions about population structuring.

Date: August 1997

Creator: Schober, Cassandra C. (Cassandra Carolyn)

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

The Reproductive Consequences of Carriers of Methylenebisacrylamide-Induced Balanced Reciprocal Translocations in Mus Musculus

N,N'-methylenebisacrylamide (MBA) was studied because of its effectiveness in inducing heritable translocations in germ cells of male mice. The health impact of translocations was studied through anatomical analysis of the progeny of semisterile translocation carriers. As expected, the semisterility of translocation carriers resulted primarily from embryonic death during periimplantation stages due to unbalanced chromosome sperm segregants. Among conceptuses that survived to mid- and late-gesta… more

Date: May 1989

Creator: Kile, Joanna L. (Joanna Le)

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Teratogenic and Mutagenic Potential of Triethylenemelamine, Ethyl Methanesulfonate, and N-Ethyl-N-Nitrosourea for Causing Fetal Anomalies in Mus Musculus

In five separate experiments, weight-adjusted doses of TEM, EMS, and ENU were injected intraperitoneally into twelve week-old female mice six hours after mating. On day seventeen of gestation, the females were sacrificed and their uterine contents were examined. The effect of each agent was determined by its ability to cause malformations and death to the developing embryos. All treatment groups showed statistically significant elevated levels of malformations in comparison to their correspondi… more

Date: December 1987

Creator: Gans, Murry J. (Murry Joe)

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Endogenous Nucleotide Pools in Growing Cells of Azotobacter Vinelandii

The objective of this investigation was to examine the changes in the nucleotide pools of Azotobacter vinelandii during the growth cycle. Endogenous ribonucleotides were extracted from A. vinelandii using trichloroacetic acid (TCA; 12% w/v). The 5' mono-, di- and triphosphates of adenine, guanine, uracil and cytosine were separated and quantified by anion-exchange high performance liquid chromatography. Results indicated that the adenylate energy charge of A. vinelandii paralleled the growth ra… more

Date: August 1987

Creator: Lee, Yick-Shun

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Changes in Gene Expression Levels of the Ecf Sigma Factor Bov1605 Under Ph Shift and Oxidative Stress in the Sheep Pathogen Brucella Ovis

Brucella ovis is a sexually transmitted, facultatively anaerobic, intracellular bacterial pathogen of sheep (Ovis aries) and red deer (Cervus elaphus). Brucella spp. infect primarily by penetrating the mucosa and are phagocytized by host macrophages, where survival and replication occurs. At least in some species, it has been shown that entry into stationary phase is necessary for successful infection. Brucella, like other alphaproteobacteria, lack the canonical stationary phase sigma factor ?s… more

Date: December 2012

Creator: Kiehler, Brittany Elaine

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Short Term Effects of External Electric Fields on Electrical Activity of the Pineal Gland in Rats

The effects of short term exposure (5 minutes) to EEFs at relatively high dosages (10, 25, 39, kV/m) on the electrical activity in rat pineal glands was studied. Daytime and nighttime recordings were taken from an implanted microelectrode in the gland. The data show that (1) both the activity and frequency were enhanced when the animals were exposed to EEFs at 39 kV/m continuously and discontinuously; (2) the later condition yielded a sustained increase (36%) whereas the former a brief (10 sec)… more

Date: May 1996

Creator: Vu, Hung Quoc

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Stretching the Flexible Myosin II Subfragment Using the Novel Gravitational Force Spectroscope, and the Uncoiling of S2

Familial Hypertrophic cardiomyopathy (HCM) causes ventricle walls to thicken and often leads to sudden death especially in adults. Mutations in the subfragment 2 (S2) of β-cardiac myosin are implicated in the genetic disorder. This S2 region is a coiled-coil rod region resulting from the dimeric form of myosin II. It has been proposed that an elastic quality allows normal S2 to absorb force during the powerstroke according to the sliding filament model. To test the flexibility of single mo… more

Date: May 2010

Creator: Dunn, James W.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Novel Role of Trypsin in Zebrafish

It has been shown previously in our laboratory that zebrafish produce trypsin from their gills when they are under stress, and this trypsin is involved in thrombocyte activation via PAR2 during gill bleeding. In this study, I investigated another role of the trypsin that is secreted from zebrafish. This investigation has demonstrated a novel role of trypsin in zebrafish. Not only did this investigation demonstrate the role of trypsin in zebrafish behavior, but also it showed that PAR2 might be … more

Date: May 2013

Creator: Alsrhani, Abdullah Falleh

Item Type: Thesis or Dissertation

Partner: UNT Libraries

A laboratory course in experimental genetics for the biology major.

This manual has been designed for a class of twenty- four students concurrently enrolled in the lecture course. The laboratory aids in the learning process and fosters an interest in the science of genetics. This manual and the experiments contained within are both informative and fun. The manual correlates with and expands upon the genetics course. Each investigation, with the exception of the Drosophila melanogaster project, can be completed in a 3-4 hour timeframe. This manual provides a “ha… more

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Date: December 2001

Creator: Lux, Melissa McNeil

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

College Freshman Biology Two Semester Course: Integrating Deep Processing Teaching Techniques

Development of a college level freshman biology course was undertaken in response to government reports that American students have fallen behind students of other countries in the area of the sciences. Teaching strategies were investigated to accomplish two objectives, to define essential academic material to include in the course and to investigate teaching techniques that would increase deep processing of the information. An active process that consisted of applying the cognitive information… more

Date: May 2002

Creator: Blevins, Mary Jean

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

The Use of Genetic Polymorphisms and Discriminant Analysis in Evaluating Genetic Polymorphisms as a Predictor of Population

Discriminant analysis is a procedure for identifying the relationships between qualitative criterion variables and quantitative predictor variables. Data bases of genetic polymorphisms are currently available that group such polymorphisms by ethnic origin or nationality. Such information could be useful to entities that base financial determinations upon predictions of disease or to medical researchers who wish to target prevention and treatment to population groups. While the use of genetic in… more

Date: May 2002

Creator: Howell, Bruce F.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Effects of Daily Oral Injections of Quercetin on Implanted Colon-25 Tumor Growth in Balb-C Mice

The effects of three oral dosages (0.4 mg, 0.8 mg, and 1.6 mg) of quercetin on Colon-25 tumors implanted in Balb-c mice were studied. The data in this study show that: (1) certain dosages of quercetin in alcohol solutions, reduces the weight, and size of implanted Colon-25 tumors in Balb-c mice, (2) these same dosages of quercetin all produce a profound neutrophilia combined with a significant lymphopenia at day 20 post-implantation, and (3) there was relatively little evidence of histological … more

Date: May 2000

Creator: Hayashi, Adam

Item Type: Thesis or Dissertation

Partner: UNT Libraries

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Syllabus for Advanced Placement Biology

The purpose of this syllabus is to provide a working copy to those teachers of the advanced placement biology course taught at the high school level. Reference materials used were the Texas Education Agency ( TEA ) approved Campbell text Biology and the College Board's, Advanced Placement Biology Laboratory Manual. The syllabus is divided into major topics with outlined notes and includes laboratory exercises as recommended by the College Board. The AP biology course is intended to be equivalen… more

Date: August 1999

Creator: Turk, Cathy Christine

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Syllabus Outline for Genetics Lecture and Laboratory

This work is intended to be used as a teaching tool in conjunction with the text cited. It is written in outline format, highlighting the major concepts of each pertinent chapter. In this format, the concepts can be expanded upon at the discretion of the instructor. This work is to be used as a guide for lecture. The basic concepts contained in the outline are in such a format as to be able to work in more information regarding the subject matter if needed. The instructor can work from this out… more

Date: December 1999

Creator: Preston, E. Lynn

Item Type: Thesis or Dissertation

Partner: UNT Libraries

General Biology Lecture and Laboratory Curriculum Outline in a Two or Four-Year College

In July of 1999, I wrote to 24 Texas junior and community colleges (and one four-year institution) describing my thesis agenda of a general biology lecture and laboratory syllabus for introductory biology students. I requested the titles and authors of the general biology textbooks and laboratory manuals they were currently using, the publishers of these texts, and the edition of said texts. I then contacted publishers of the various textbooks who, in turn, directed me to the Dallas-area repres… more

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Date: August 2000

Creator: Moreland, Amy L.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Mutagenized HLA DNA Constructs: Tools for Validating Molecular HLA Typing Methodologies

This study describes the development and validation of mutagenized cloned DNA constructs, which correspond to the polymorphic regions of the class II region of the HLA complex. The constructs were used to verify the allelic specificity of primers and probes in polymerase chain reaction (PCR)-based HLA typing assays such as Sequence Specific Primers (SSP) and Sequence Specific Oligonucleotide Probes (SSOP). The constructs consisted of the entire polymorphic region of exon 2 of class II HLA allel… more

Date: May 1999

Creator: Schulte, Kathleen Q.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Synthetic Peptides Model Instability of Cardiac Myosin Subfragment-2

Hypertrophic cardiomyopathy (HCM), a heart-related abnormality, is the most prevalent cause of sudden death in young athletes at sporting events. A cluster of cardiomyopathy mutations are localized in β-cardiac myosin at the N-terminal region of subfragment-2. Using resonance energy transfer probes, a synthetic peptide model system was developed to study stability of the coiled coil (S2 fragment) structure by determining monomer-dimer equilibrium of the peptide. Fluorescence resonance energy tr… more

Date: August 2013

Creator: Taei, Nasrin

Item Type: Thesis or Dissertation

Partner: UNT Libraries

Evaluation of virulence in wild type and pyrimidine auxotrophs of Pseudomonas aeruginosa using the eukaryotic model system Caenorhabditis elegans.

The human opportunistic pathogen, Pseudomonas aeruginosa PAO1, has been shown to kill the nematode Caenorhabditis elegans. C. elegans has been a valuable model for the study of bacterial pathogenesis, and has reinforced the notion that common virulence and host defense mechanisms exist. Recently, the pyrimidine pathway was shown to regulate virulence levels. Therefore, mutations in the pyrimidine pathway of PAO1 showed decrease virulence in the nematode. When starving the nematode, bacterial… more

Access: Restricted to the UNT Community Members at a UNT Libraries Location.

Date: August 2004

Creator: Anvari, Sara

Item Type: Thesis or Dissertation

Partner: UNT Libraries

Animal Contribution to Human Medicine

The use of animal models in research has led to a fierce debate between animal rights activists and scientists. The former claim that little useful information is gained from animal studies and the suffering of animals does not preclude any treatments which may be used to treat human illnesses. Yet, research scientists claim that in vivo animal models are of absolute necessity to developing treatments and cures to disease. To determine the necessity of animal use, one must examine the models c… more

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Date: May 2001

Creator: Kvernes, Kayce

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Interrelational Laboratory Information System for Data Storage and Retrieval

The necessity for a functional user friendly laboratory data management program has become evident as the quantity of information required for modern scientific research has increased to to titanic proportions. The required union of strong computer power, ease of operation, and adaptability have until recently been outside the realm of most research laboratories. Previous systems, in addition to their high cost, are necessarily complex and require software experts in order to effect any changes… more

Date: August 1989

Creator: Gregory, Michael W. (Michael Walter)

Item Type: Thesis or Dissertation

Partner: UNT Libraries

Integrating Concepts in Modern Molecular Biology into a High School Biology Curriculum

More so than any other science in the past several decades, Biology has seen an explosion of new information and monumental discoveries that have had a profound impact on much more than the science itself. Much of this has occurred at the molecular level. Many of these modern concepts, ideas, and technologies, as well as their historical context, can be easily understood and appreciated at the high school level. Moreover, it is argued here that the integration of this is critical for making bio… more

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Date: August 2003

Creator: Parker, Timothy P.

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Attenuation of Escherichia Coli Aspartate Transcarbamoylase Expressed in Pseudomonas Aeruginosa Mutant and Wild Type Strains

No apparent repression of pyr gene expression in Pseudomonas aeruginosa is observed upon addition of exogenous pyrimidines to the growth medium. Upon introduction of the subcloned Escherichia coli pyrBI genes for aspartate transcarbamoylase (ATCase) into a P. aeruginosa pyrB mutant strain, repression was observed in response to exogenously fed pyrimidine compounds. The results proved that it is possible to bring about changes in pyrimidine nucleotide pool levels and changes in transcriptional r… more

Date: December 1994

Creator: Liu, Haiyan, 1966-

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Subcloning and Nucleotide Sequence of the xylO/PUWCMA Region from the Pseudomonas putida TOL Plasmid pDK1

The TOL plasmids of Pseudomonas putida encode enzymes required for the oxidation of toluene and other related aromatic compounds. These genes are organized into two operons, the xylUWCMABN operon (upper), and the xylXYZLTEGFJQKIH operon (lower). Here we report the nucleotide sequence of a 7107 bp segment of the TOL pDK1 plasmid encoding the region just upstream of the "upper" operon through the genes encoding xylUWCMA. Sequence analysis, comparison of base-usage patterns, codon-usage patterns, … more

Date: December 1997

Creator: Guigneaux, Michelle M. (Michelle Marie)

Item Type: Thesis or Dissertation

Partner: UNT Libraries