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An Immunological Study of Adults with Down Syndrome

Description: The high susceptibility to infection in persons with Down Syndrome (DS) has led some investigators to explore the possibility of a defect in the immune system. Studies to date indicate no defect in humoral immunity suggesting that the defect might be in the cellular immune functions, but no specific defect has been found. Our investigation of the cellular immune system of adult DS patients was conducted by examining (1) the number and function of T-lymphocytes, (2) the phagocytic function of granulocytes, (3) the level of superoxide dismutase-1 (SOD-1) in leukocytes, and (4) the effects of SOD-1 on lymphocyte and granulocyte functions.
Date: August 1983
Creator: White, Olivia Masih
Partner: UNT Libraries

The Teratogenic Effects of Nocodazole and Acrylamide in Mus Musculus

Description: In two separate experiments, weight adjusted doses of nocodazole and acrylamide were injected intraperitoneally at various time intervals into twelve week old female mice. Within the nocodazole experiment, the doses were injected at varying time intervals before and after mating. On day seventeen of gestation, the female mice were sacrificed and their uterine contents examined. Nocodazole induced a significant increase in reproductive pathology per total implants when administered one hour after mating to the (SECxC57BL)F, stock: 5.00% total deads, 70.23% moles, and 3.41% abnormal fetuses. Acrylamide treatment produced a significant reduction in live births when administered six hours after mating: 50.86% moles and 46.46% living fetuses per total implants.
Date: May 1989
Creator: Oliva, Jean L. (Jean Louise)
Partner: UNT Libraries

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

Description: 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-gestation stages, there was an increased incidence of developmental anomalies including fetal death and phenotypic defects. These abnormalities are associated with unbalanced chromosome complements that allow survival to the later stages of development.
Date: May 1989
Creator: Kile, Joanna L. (Joanna Le)
Partner: UNT Libraries

Mutagenic Potential of Tetramethylthiuram Disulfide (42-S Thiram) on the Germ Cell Stages of Drosophila melanogaster

Description: Tetramethylthiuram disulfide (42-S Thiram), a carbamate fungicide was studied for its mutagenic potential on the germ cell stages of wild-type male Drosophila melanogaster. The mutagenicity was tested using the sex-linked recessive lethal assay (SLRL). Any lethals induced in the F2 generation were evidenced by the absence of wild-type males. Although there was an increase in mutation rates in the 42-S Thiram treated wild-type males over the control wild-type males, it was not significantly higher. According to the laboratory conditions in this preliminary study, tetramethylthiuram disulfide failed to produce mutagenic effect.
Date: December 1990
Creator: Lowe-Chatham, Janice E. (Janice Elaine)
Partner: UNT Libraries

A New LC Column for the Separation and the Quantitation of Nucleotides

Description: A new column, Dionex AS4A, (polystyrenedivinylbenzene matrix) used for the separation of ribonucleotides and deoxyribonucleotides for the first time, and previously used for ion analysis was found superior to conventional silica columns because it separates ribonucleotides and deoxyribonucleotides. Resolution of dGTP was not possible with the Dionex column and CTP and GDP often co-eluted. Using conventional silica columns, monophosphates separated from diphosphates and diphosphates from triphosphates. Using the new Dionex column resolves all three simultaneously. The Dionex column resolved nucleotides with sharper peaks than silica columns, and the longer its retention time the better was the resolution. This Dionex column is stable, with 80 runs possible without cleaning while resolving ribonucleotides and deoxyribonucleotides to the picomole level.
Date: December 1987
Creator: Brock, Patricia C. (Patricia Charlene)
Partner: UNT Libraries

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

Description: 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 corresponding control groups. The reproductive damage induced in these experiments cannot be singularly attributed to teratogenesis or mutagenesis but a combination of the two.
Date: December 1987
Creator: Gans, Murry J. (Murry Joe)
Partner: UNT Libraries

Gene Dosage Study on Human Chromosome 22

Description: A gene dosage study was conducted on a rare complete trisomy 22 human fibroblast cell line utilizing three lysosomal enzymes, ∝-iduronidase, ∝-galactosidase B, and arylsulfatase A, whose genes are located on chromosome 22 and two control enzymes, ,β-hexosaminidase A and -- fucosidase, with genes not on chromosome 22. A gene dosage effect was clearly demonstrated for an early passage number of the fibroblasts; however, later passage numbers gave inconclusive results. This study suggests that gene dosage studies must be carefully designed to be conducted only on early, matched passage number cells. ∝-fucosidase gave anomalous results most likely due to pleiotropic effects. The present gene dosage study confirmed the trisomic nature of the cell line studied and suggests that this type of study may be a useful diagnostic tool for small deletions, additions, or unbalanced translocations.
Date: December 1986
Creator: Hinkley, Craig S. (Craig Steven)
Partner: UNT Libraries

The Effect of Long-Term Moderate Amounts of Ethanol on Paraventricular Nuclei Activity on Cold Stressed Adult Rats

Description: The effects of moderate, long-term intake of ethanol on the hypothalamic response to cold stress were examined. The long-term experimental animals were given .25 ml of 28% ethanol or .25 ml of water orally once a day, five days a week for fourteen months. A stainless steel electrode was then surgically implanted into the paraventricular nucleus, after which the animal was subjected to cold stress (-150 C, 10 min.). Recordings were taken in the forms of frequency and activity. The data clearly indicate that: (1) alcohol fed rats exhibited a suppressed response to cold stress compared to sham-fed rats; (2) this suppression of activity occurred at the level of the hypothalamus, and (3) mortality was significantly lower in alcohol-fed males than it was in sham fed males. This study clearly points out the need for further work in the area of the beneficial effects of moderate doses of alcohol.
Date: December 1990
Creator: McKinnon, Mark S. (Mark Steven)
Partner: UNT Libraries

A Two Semester Life Science Syllabus for Use in Texas Public Schools with Seventh Grade Students

Description: The problem of using a state adopted textbook written to apply to a large body of students with varying interests and needs was overcome by using a detailed syllabus that arranged course content in a meaningful sequence that appealed to student interest. The outlined syllabus prepared a two semester life science curriculum to be used by the teacher to guide lesson planning. Both semesters were divided into three units each. Materials included in the syllabus were given to actual student groups in real classroom settings. Since hands on learning was an important part of classroom instruction, two laboratory sections were included in the appendices to be used with the syllabus.
Date: May 1995
Creator: Edwards, Gail G. (Gail Graham)
Partner: UNT Libraries

Attitudes Toward Teaching and Research Among Biology Faculty in Texas Institutions of Higher Education

Description: This study investigated the attitudes toward teaching and research among biology faculty in Texas institutions of higher learning. The purposes of the study were to: 1) determine what the attitudes of Texas biology faculty were toward teaching; 2) to determine the attitudes of Texas biology faculty toward research; 3) to determine if biology faculty attitudes toward teaching vary according to faculty rank; 4) to determine if biology faculty attitudes toward research vary according to faculty rank; 5) to determine if attitudes of biology faculty in Texas toward teaching vary according to institutional type; and 6) to determine if attitudes of biology faculty in Texas toward research vary according to institutional type.
Date: December 1993
Creator: Salehi, Faiz
Partner: UNT Libraries

Advanced Molecular and Microbial Techniques: a Complete Laboratory Notebook

Description: The purpose of this project is to produce a complete and thorough notebook that may be used to supplement laboratory coursework. Its intent is to be used primarily by the students to aid them in understanding background information and the proper laboratory procedures involved in various types of experiments. The laboratory notebook is a summation of all the experiments and procedures used in the six-credit hour Advanced Microbial and Molecular Biology (BIOL 5160) course offered during the summer semester at the University of North Texas. This class is a team taught effort by Professors O'Donovan and Kunz. The course is constructed as an intensive practice exercise to teach the student about gene mutations, biosynthetic pathways, preparation and analysis of plasmid DNA, and many other topics included in the notebook.
Date: May 1998
Creator: Brito-Rodriquez, Carmen Lydia
Partner: UNT Libraries

Genetics Lecture and Laboratory Syllabus for a Junior-Level Course

Description: The following is a complete syllabus for a college level genetics course. The syllabus contains lecture outlines and notes for each chapter, along with a list of transparencies needed. The quizzes and exams are prepared and placed at the beginning of the syllabus. The beginning of the course will consist of a lecture to introduce the students to the basics of genetics, followed by many applications of genetics. The process of cell division will be mastered by the students, as well as Mendelian genetics, quantitative genetics, chromosome mapping, and inheritance. The replication, synthesis, and organization of DNA are also discussed within the lectures. The final topics that will be covered using this syllabus are genetics of cancer and immunology and population genetics. These topics are essential for a detailed genetics course. The syllabus is written in great detail, and will require a full semester to be completed. The book used in association with this syllabus is Essentials of Genetics by William S. Klug and Michael R. Cummings.
Date: August 1999
Creator: Harper, Kasey
Partner: UNT Libraries

Oral Microbiology

Description: Recent studies regarding research on oral microorganisms and the oral diseases are presented. The normal flora of the mouth and the oral environment are first described. Dental plaque and dental caries are primary causes of oral disease. Streptococcus mutans is the major contributor in the initiation and progression of dental caries. Lactobacillus, Actinomyces, and Veillonella are other genera of bacteria linked to dental caries. Periodontitis and gingivitis are periodontal diseases that are caused by oral microorganisms. New research has indicated that various antimicrobial agents and techniques to eliminate or lessen the severity of periodontal diseases. Premature delivery of low birth weight babies in pregnant women has been strongly linked to periodontal disease. Present and future microbiological tests are available to easily determine the causative organisms for most oral diseases that help in diagnosis and treatment of a particular disease.
Date: August 1998
Creator: Osman, Shaiesta
Partner: UNT Libraries

The Effect of the Use of Laser Video Disc on Achievement, Attitude, and Confidence of High School Biology Students

Description: The purpose of the study was to determine the effects of level III video disc instruction on high school biology students. There were three areas studied: students' achievement in biology, students' attitude toward biology, and confidence. The experimental group consisted of 70 biology students. The control group also consisted of 70 biology students. The teacher of the experimental group used level in video disc instruction to teach about invertebrates, vertebrates, human systems, and plants throughout the semester. The teachers of the control group taught the same topics during the same period using the traditional lecture method and without level III video disc instruction. Students took the Biology Achievement Test, the Purdue Master Attitude Scale, and the Confidence in Learning Inventory before and after the treatment period. A t-test on the pretest scores of the experimental group and the control group showed no significant difference between the two groups. The experimental group also took the Technology Preference Survey after the treatment period.
Date: August 1994
Creator: Garza, Federico (Federico Angel)
Partner: UNT Libraries

The Effects of a Strategic Thinking Program on the Cognitive Ability of Seventh Grade Students

Description: This study used a posttest only design to determine the effects of a strategic thinking program on the Cognitive Abilities Test (CogAT, Form 4) scores of seventh graders who received direct instruction in Strategic Thinking Skills (STS) with the scores of seventh graders who did not receive direct instruction in STS. The study was conducted in a large suburban middle school in north Texas.
Date: August 1993
Creator: Houchins, Joyce S. (Joyce Ann S.)
Partner: UNT Libraries

Cerebral Laterality and Leadership Assessment

Description: The major purpose of this study was to determine whether a relationship exists between cerebral laterality dominance and leadership behavior and traits. An additional purpose was to determine whether a relationship exists between cerebral laterality dominance and gender, ethnicity, and educational position.
Date: December 1991
Creator: Horn, Barry L. (Barry Lee)
Partner: UNT Libraries

Radial Compression High Performance Liquid Chromatography as a Tool for The Measurement of Endogenous Nucleotides in Bacteria

Description: High performance liquid chromatography was used to measure ribonucleoside triphosphates in microbial samples. Anion exchange columns in a radial compression module were used to separate and quantify purine and pyrimidine ribonucleotides. Endogenous ribonucleoside triphosphates were extracted from Escherichia coli and pseudomonas aeruginosa using three different solvents, namely trifluorocetic acid (TFA; 0.5M), trichloroacetic acid (TCA; 6 per cent w/v) and formic acid (1.0M) Extracts were assayed for uridine 5'-triphosphate (ATP), and guanosine 5'-triphosphate (GTP) by using anion exchange radial compression high performance (pressure) liquid chromatography. The three extraction produres were compared for yield of triphosphates. E. coli, the TFA extraction procedure was more sensitive and reliable than TCA and formic acid extraction procedures, but , in P. aeruginosa, the best yields of ATP and GTP were obrained following extraction with TFA. Yields of UTP and CTP increased when extraction was performed in TCA. These data illustrate that different extraction produres produce different measures for different triphosphates, a point often overlooked.
Date: August 1986
Creator: Dutta, Probir Kumar
Partner: UNT Libraries

Cross-Cultural Validity of the Test of Non-Verbal Intelligence

Description: The purpose of this study was to investigate the extent to which a non-verbal test of intelligence, the Test of Non-Verbal Intelligence (TONI), may be used for assessing intellectual abilities of children in India. This investigation is considered important since current instruments used in India were developed several years ago and do not adequately reflect present standards of performance. Further, current instruments do not demonstrate adequate validity, as procedures for development and cultural transport were frequently not in adherence to recommended guidelines for such practice. Data were collected from 91 normally achieving and 18 mentally retarded Indian children, currently enrolled in elementary schools. Data from an American comparison group were procured from the authors of the TONI. Subjects were matched on age, grade, and area of residence. Subjects were also from comparative socioeconomic backgrounds. Literature review of the theoretical framework supporting cross-cultural measurement of intellectual ability, a summary of major instruments developed for cross-cultural use, non-verbal measures of intellectual ability in India, and issues in cross-cultural research are discussed, with recommended methodology for test transport. Major findings are: (a) the factor scales derived from the Indian and American normally achieving groups indicate significant differences; (b) items 1, 3, 5, 8, 10, and 22 are biased against the Indian group, though overall item characteristic curves are not significantly different; (c) mean raw scores on the TONI are significantly different between second and third grade Indian subjects; and (d) mean TONI Quotients are significantly different between normally achieving and mentally retarded Indian subjects. It is evident that deletion of biased items and rescaling would be necessary for the TONI to be valid in the Indian context. However, because it does discriminate between subjects at different levels of ability, adaptation for use in India is justified. It may prove to be a more ...
Date: August 1988
Creator: Parmar, Rene S. (Rene Sumangala)
Partner: UNT Libraries

Pyrimidine Metabolism in Rhizobium: Physiological Aspects of Pyrimidine Salvage

Description: The objective of this research was to study the pyrimidine salvage pathways of Rhizobium. Three approaches were used to define the pyrimidine salvage pathways operative in two species of Rhizobium, R. meliloti and R. leguminosarum . The first approach was to ascertain the pyrimidine bases and nucleosides that could satisfy the pyrimidine requirement of pyrimidine auxotrophs. Uracil, cytosine, uridine or cytidine all satisfied the absolute pyrimidine requirement. The second approach was to select for mutants resistant to 5-fluoropyrimidine analogues which block known steps in the interconversion of the pyrimidine bases and nucleosides. Mutants resistant to 5-fluorouracil lacked the enzyme uracil phosphoribosyltransferase (upp ) and could no longer use uracil to satisfy their pyrimidine requirement. Mutants resistant to 5-fluorocytosine, while remaining sensitive to 5- fluorouracil, lacked cytosine deaminase (cod) and thus could no longer use cytosine to satisfy their pyrimidine auxotrophy. The third approach used a reversed phase HPLC column to identify the products that accumulated when cytidine, uridine or cytosine was incubated with cell extracts of wild type and analogue resistant mutants of Rhizobium. When cytidine was incubated with cell extracts of Rhizobium wild type, uridine, uracil and cytosine were produced. This Indicated that Rhizobium had an active cytidine deaminase (cdd) and either uridine phosphorylase or uridine hydrolase. By dialyzing the extract and reincubating it with cytidine, uridine and uracil still appeared. This proved that it was a hydrolase ( nuh ) rather than a phosphorylase that degraded the nucleoside. Thus, Rhizobium was found to contain an active cytidine deaminase and cytosine deaminase with no uridine phosphorylase present. The nucleoside hydrolase was active with cytidine, uridine and to a far lesser extent with purines, adenosine and inosine. When high concentrations of cytidine were added to mutants devoid of hydrolase, cytosine was produced from cytidine - 5-monophosphate by the sequential action ...
Date: December 1989
Creator: Ibrahim, Mohamed M.
Partner: UNT Libraries

Effects of 5-hydroxytryptamine on Mouse Lumbar Motor Activity During Postnatal Development

Description: The lumbar motor activity in isolated spinal cords of 72 postnatal Balb/C mice aged 2, 5, 10 and 21 days (PN2-21) was electroneurographically recorded (ENG) via bilateral ventral roots following treatment with three different concentrations (25, 100 and 200 pM) of the neurotransmitter, 5-hydroxytryptamine (5-HT), i.e., serotonin, to determine its effects on spinal pattern generation.
Date: December 1998
Creator: Lowe-Chatham, Janice E. (Janice Elaine)
Partner: UNT Libraries

Measurement of Feedback Inhibition In Vivo and Selection of ATCase Feedback Altered Mutants in Salmonella typhimurium

Description: Aspartate transcarbamoylase (ATCase; encoded by pyrBI genes) is one of the most studied regulatory enzymes in bacteria. It is feedback inhibited by cytidine triphosphate (CTP) and activated by adenosine triphosphate (ATP). Much is known about the catalytic site of the enzyme, not nearly as much about the regulatory site, to which CTP binds. Until now a positive selection for feedback-modified mutants was not available. The selection we have developed involves the use of a pyrA deletion in S. typhimurium. This strain lacks carbamoylphosphate and requires both a pyrimidine and arginine for growth. In this strain citrulline is used to satisfy the pyrimidine and arginine requirements. The minimal flow through the pyrimidine pathway from the citrulline-produced carbamoylphosphate is exquisitely sensitive to feedback control of ATCase by CTP. By elevating the CTP pool, via exogenous cytidine, in a strain that also contains a cytidine deaminase mutant (cdd) growth can be stopped completely, indicating 100% inhibition. It was therefore possible to measure in vivo feedback inhibition of ATCase among the citrulline users and to isolate a family of ATCase regulatory mutants with either modified or no response to effectors.
Date: August 1989
Creator: Bailey, Andrea J., 1952-
Partner: UNT Libraries