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Full-Text Articles in Life Sciences

Junior High Students' Perceptions Of The Fitnessgram Fitness Test, Emily Mcomber Welch Jul 2007

Junior High Students' Perceptions Of The Fitnessgram Fitness Test, Emily Mcomber Welch

Theses and Dissertations

The Fitnessgram is a battery of fitness tests designed for children and adolescents. These tests include aerobic capacity, body composition, muscle strength and endurance, and flexibility. Students are not compared to each other, rather to health fitness standards, specific to age and gender, which indicate good health. The purpose of this study was to identify student perceptions of the Fitnessgram fitness test. This study used surveys (N=82), and follow-up focus-group interviews (N=16) to identify student perceptions of the Fitnessgram fitness test. Results using the constant comparative method revealed three major categories: (1) students' perceptions of the purpose of fitness testing, …


The Influence Of Performance Level And Setting On Collegiate Athletes' Motivational Profiles, Shareen Brooke Smith Jul 2007

The Influence Of Performance Level And Setting On Collegiate Athletes' Motivational Profiles, Shareen Brooke Smith

Theses and Dissertations

The purpose of this study was to determine if motivational profiles of individual collegiate team sport athletes differ across ability levels (High, Middle, and Low) and settings (Team Practice, Competition, and Personal Practice). The athletes task and ego disposition, autonomy, and contextual motivation, were assessed using the Perception of Success Questionnaire (POSQ), Sport Climate Questionnaire (SCQ), and Sport Motivational Scale (SMS), pre and postseason. Their anxiety levels and situational motivation were measured using the Sport Anxiety Scale (SAS) and the Situational Motivational Scale (SIMS) during the season. The General Causality Orientations Scale (GCOS) was used pre and postseason to assess …


Amp-Activated Protein Kinase Kinase Activity And Phosphorylation Of Amp-Activated Protein Kinase In Contracting Muscle Of Sedentary And Endurance Trained Rats, Denise Hurst Jul 2007

Amp-Activated Protein Kinase Kinase Activity And Phosphorylation Of Amp-Activated Protein Kinase In Contracting Muscle Of Sedentary And Endurance Trained Rats, Denise Hurst

Theses and Dissertations

This study was designed to examine activity of AMP-activated protein kinase kinase (AMPKK) and AMP-activated protein kinase (AMPK) in muscles from control (C) and endurance trained (T) rats. Rats were trained 5 days/wk, 2 hr/d for 8 wks at a final intensity of 32 m/min up a 15% grade with 30 second sprints at 52 m/min every 10 min. Gastrocnemius muscles were stimulated in situ in T and C rats for 5 min at frequencies of 0.4/sec and 1/sec. Gastrocnemius LKB1 protein, a putative component of the AMPKK complex (LKB1, STRAD, and MO25), increased approximately 2-fold in response to training. …


Development Of Chemomechanical Functionalization And Nanografting On Silicon Surfaces, Michael Vernon Lee Jul 2007

Development Of Chemomechanical Functionalization And Nanografting On Silicon Surfaces, Michael Vernon Lee

Theses and Dissertations

Progress in chemomechanical functionalization was made by investigating the binding of molecules and surface coverage on the silicon surface, demonstrating functionalization of silicon with gases by chemomechanical means, analyzing atomic force microscopy probe tip wear in atomic force microscopy (AFM) chemomechanical nanografting, combining chemomechanical functionalization and nanografting to pattern silicon with an atomic force microscope, and extending chemomechanical nanografting to silicon dioxide. Molecular mechanics of alkenes and alkynes bound to Si(001)-2x1 as a model of chemomechanically functionalized surfaces indicated that complete coverage is energetically favorable and becomes more favorable for longer chain species. Scribing a silicon surface in the presence …


Cloning And Characterization Of The Salt Overly Sensitive 1 (Sos1) Gene In Chenopodium Quinoa Willd., Taylor Brian Turner Jul 2007

Cloning And Characterization Of The Salt Overly Sensitive 1 (Sos1) Gene In Chenopodium Quinoa Willd., Taylor Brian Turner

Theses and Dissertations

Salt tolerance is a commercially important trait that affects plant species around the globe. Cellular response to saline environments is a well studied but complex system that is far from being completely understood. The SALT OVERLY SENSITIVE 1 (SOS1) gene is a critical component of salt tolerance in many species, encoding a plasma membrane Na+/H+ antiporter that plays an important role in germination and growth in saline environments. Here we report a preliminary investigation of salt tolerance in quinoa (Chenopodium quinoa Willd.). Quinoa is a halophytic grain crop of the Chenopodiaceae family with impressive nutritional content and an increasing world-wide …


Palmitoylation And Oxidation Of The Cysteine Rich Region Of Snap-25 And Their Effects On Protein Interactions, Derek Luberli Martinez Jul 2007

Palmitoylation And Oxidation Of The Cysteine Rich Region Of Snap-25 And Their Effects On Protein Interactions, Derek Luberli Martinez

Theses and Dissertations

Neurons depend upon neurotransmitter release through regulated exocytosis to accomplish the immense processing performed within the central nervous system. The SNARE hypothesis points to a family of proteins that are thought to enable the membrane fusion that leads to exocytosis. The secondary structure of SNAP-25 is unique among SNARE proteins in that it has two alpha helical SNARE motifs and a cysteine rich (C85, C88, C90, C92) membrane interacting region but notransmembrane domain. The cysteines may be modified by palmitoylation or oxidation but the role of these modifications in vivo is not well understood. Our goal is to elucidate possible …


Protein Coevolution And Coadaptation In The Vertebrate Bc1 Complex, Kimberly Kay Baer Jul 2007

Protein Coevolution And Coadaptation In The Vertebrate Bc1 Complex, Kimberly Kay Baer

Theses and Dissertations

The cytochrome bc1 complex of the mitochondrial electron transport chain accomplishes the enzymatic reaction known as the modified Q-cycle. In the Q-cycle the bc1 complex transports protons from the matrix to the intermembrane space of the mitochondria, creating the proton gradient used to make ATP. The energy to move these protons is obtained by shuttling electrons from the coenzyme ubiquinol (QH2) to coenzyme ubiquinone (Q) and the mobile cytochrome c. This well studied complex is ideal for examining molecular adaptation because it consists of ten different subunits, it functions as a dimer, and it includes at least five different active …


The Origins, Evolution, And Phylogeny Of The Praying Mantises (Dictyoptera: Mantodea), Gavin John Svenson Jul 2007

The Origins, Evolution, And Phylogeny Of The Praying Mantises (Dictyoptera: Mantodea), Gavin John Svenson

Theses and Dissertations

The relatively small insect order Mantodea (praying mantises) is comprised of approximately 2,366 described species distributed in 436 genera. Members of the group occupy diverse habitats and are distributed across the globe, though their greatest numbers and diversity are concentrated primarily in the tropics. Though continental endemism is common, many groups have a broad global distribution. An immense diversity of morphology is exhibited across the order with adult mantises ranging in size from 2cm to ~25cm, and appearing like a dead leaf, a piece of quartz rock, or a blade of grass. The diversification and specialization of mantises in ecologically …


Synthesis Of Resveratrol And Its Analogs, Phase-Transfer Catalyzed Asymmetric Glycolate Aldol Reaction, And Total Synthesis Of 8,9-Methylamido-Geldanamycin, Jing Liu Jul 2007

Synthesis Of Resveratrol And Its Analogs, Phase-Transfer Catalyzed Asymmetric Glycolate Aldol Reaction, And Total Synthesis Of 8,9-Methylamido-Geldanamycin, Jing Liu

Theses and Dissertations

The phytoalexin resveratrol and its acetyl analogs have been made using a decarbonylative Heck reaction. The acid chloride derived from 3,5-dihydroxybenzoic acid was coupled with suitable protected 4-hydroxystyrene in the presence of palladium acetate and N,N-bis-(2,6-diisopropylphenyl)-4,5-dihydro imidazolium chloride to give the substituted stilbene in good yield as the key step. Human HL-60 cell assays showed the 4'-acetyl resveratrol variant improved activity (ED50 17 μM) relative to resveratrol (24 μM). Cinchona phase-transfer catalysts (PTC) were developed for glycolate aldol reactions to give differentially protected 1,2-diol products. Silyl enol ether of diphenylmethoxy-2,5-dimethoxyacetophenone reacted to generate benzhydryl-protected products. O-Allyl trifluorobenzyl cinchonium hydrodifluoride (20 …


Characterization Of A Novel Nuclear Variant Of Bmp2 And Coordinate Regulation Of Col11a2 And Col27a1 By The Transcription Factor Lc-Maf, Jaime Lynn Mayo Jul 2007

Characterization Of A Novel Nuclear Variant Of Bmp2 And Coordinate Regulation Of Col11a2 And Col27a1 By The Transcription Factor Lc-Maf, Jaime Lynn Mayo

Theses and Dissertations

ABSTRACT I CHARACTERIZATION OF A NOVEL NUCLEAR VARIANT OF BMP2

Bone morphogenetic protein 2 (Bmp2) is a signaling protein that was first detected by its ability to induce cartilage and bone formation. It has since been implicated in broad variety of developmental, patterning, and disease processes. To date, Bmp2 has only been known to function as an extracellular signaling molecule. However, we have obtained clear evidence for a nuclear form of Bmp2. This nuclear variant, nBmp2, contains a bipartite NLS that overlaps the site of proteolytic cleavage. The NLS remains intact and functional when translation of Bmp2 initiates from a …


Regulation Of Adrenal Steroidogenesis By Interleukin-6, Stephen A. Mcilmoil Jul 2007

Regulation Of Adrenal Steroidogenesis By Interleukin-6, Stephen A. Mcilmoil

Theses and Dissertations

Cortisol and dehydroepiandrosterone (DHEA) are steroids produced by the zona fasciculata (ZF) and reticularis (ZR), respectively, of the adrenal cortex. Both steroids are upregulated in response to adrenocorticotropic hormone (ACTH). Cortisol is a glucorticoid that is important in the regulation of inflammation and metabolism. DHEA is an adrenal androgen important in fetal growth and puberty but tends to decrease gradually after puberty in both men and women. DHEA has various effects on metabolism and immune function including inhibiting the effects of cortisol on some tissues. During the acute phase of stress, cortisol and DHEA rise due to an increase in …


Bioassessment And The Partitioning Of Community Composition And Diversity Across Spatial Scales In Wetlands Of The Bonneville Basin, Mary Jane Keleher Jul 2007

Bioassessment And The Partitioning Of Community Composition And Diversity Across Spatial Scales In Wetlands Of The Bonneville Basin, Mary Jane Keleher

Theses and Dissertations

The Bonneville Basin encompasses an area that was covered by ancient Lake Bonneville and which today lies within the Great Basin province. The Bonneville Basin is distinguished geologically by its characteristic parallel north-south mountain ranges that are separated by broad, alluviated desert basins and valleys. Benches and other shoreline features of ancient Lake Bonneville prominently mark the steep, gravelly slopes of these ranges. Numerous artesian desert springs are present at the base of the mountains and in the valley floors that form various sizes of both isolated wetlands and wetland complexes. Many these wetlands are some of the most unique …


Development And Characterization Of Microsatellite Markers For The Grain Amaranths (Amaranthus Spp. L.), Melanie Ann Mallory Jul 2007

Development And Characterization Of Microsatellite Markers For The Grain Amaranths (Amaranthus Spp. L.), Melanie Ann Mallory

Theses and Dissertations

The grain amaranths (Amaranthus hypochondriacus L., A. cruentus L., and A. caudatus L.) are important pseudocereals native to the Americas that have received increased attention for their nutritional content, specifically their balance of amino acids. The objective of this project was to produce and characterize a set of highly informative, reproducible microsatellite markers for the grain amaranths. A total of 1457 clones were sequenced from three genomic libraries enriched for the microsatellite motifs AAC, AAT and AC. Of these, 353 (24%) contained unique microsatellites. An additional 29 microsatellite loci were identified among 728 BAC-end sequences of a newly developed amaranth …


The Prolamins Of Pearl Millet, Christian B. Ricks Jul 2007

The Prolamins Of Pearl Millet, Christian B. Ricks

Theses and Dissertations

Although work on the prolamins of pearl millet (Pennisetum glaucum) has revealed partial amino acid sequences for several alcohol-soluble storage proteins (Marcellino et al. 2002) the genes encoding them have not yet been isolated. We constructed a cDNA library from developing P. glaucum seed tissue and screened it using maize zein gene probes to isolate several α-prolamin-like gene sequences. The proteins encoded by these genes generally fall into two size classes: 20.6kD and 27.1kD, which we call the 21kD and 27kD pennisetins. Both proteins are similar in composition and sequence to α-prolamins from maize, sorghum and Coix. Protein bodies that …


Regulation Of Lkb1-Strad-Mo25 Complex Expression And Activation Of Ampk In Skeletal Muscle By Thyroid Hormone, Devon Jack Branvold Jul 2007

Regulation Of Lkb1-Strad-Mo25 Complex Expression And Activation Of Ampk In Skeletal Muscle By Thyroid Hormone, Devon Jack Branvold

Theses and Dissertations

AMP-activated protein kinase (AMPK), a heterotrimeric protein which serves as a metabolic master switch in skeletal muscle, is a research target for the pharmaceutical treatment and prevention of type 2 diabetes. The expression of all of the isoforms of the subunits of AMPK and AMPK activity are increased in skeletal muscle tissue of hyperthyroid rats. Activity of AMPK is regulated by an upstream kinase (AMPKK). The LKB1-STRAD-MO25 complex is a major AMPKK in skeletal muscle. This experiment was designed to determine whether the increase in AMPK activity is accompanied by a thyroid hormone-induced increase in the expression of the LKB1-STRAD-MO25 …


Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi Jul 2007

Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi

Theses and Dissertations

3'-Carboxymethyl-3'-deoxyadenosine derivatives were prepared from 2'-O-TBDMS-3'-deoxy-3'-[(ethoxycarbonyl)methyl]adenosine (1) via simple and efficient procedures. Conversion of 1 to 5'-azido-2'-O-TBDMS-3', 5'-dideoxy -3'-[(ethoxycarbonyl) methyl] adenosine (4) was accomplished via a novel one-pot method employing 5'-activation (TosCl) followed by efficient nucleophilic displacement with tetramethylguanidinium azide. Compound 4 was converted to a 5'-[(N-methylcarbamoyl)amino] derivative (5) via one-pot reduction/acylation employing H2/Pd-C followed by treatment with p-nitrophenyl N-methylcarbamate. The latter step of this two-step process required an efficient source of p-nitrophenyl N-methylcarbamate, thus a highly efficient new method for preparing p-nitrophenyl N-alkylcarbamate was developed. N6-phenylcarbamoyl groups were introduced by treatment with phenylisocyanate, and an efficient new method for …


Development Of A Notational Analysis System To Evaluate Setting Performance In Volleyball, Nina Puikkonen Mortensen Jun 2007

Development Of A Notational Analysis System To Evaluate Setting Performance In Volleyball, Nina Puikkonen Mortensen

Theses and Dissertations

The purposes of this study were to develop a notational analysis system to evaluate volleyball setting performance independent of the actions of the hitter and to use the data to develop a Markovian transitional matrix that would make known the probabilities of specific outcomes from each setting scenario. Setting performance was analyzed based on the sets distance from the net, height of the set, and position of the set in relation to the hitter as viewed from 13 filmed competitions of a Division I intercollegiate women's volleyball team. Data from the notation of 1353 sets were used to develop a …


Dietary Fiber Intake And Body Fat Gain: A Prospective Cohort Study Of Middle-Aged Women, Kathryn Suzanne Thomas Jun 2007

Dietary Fiber Intake And Body Fat Gain: A Prospective Cohort Study Of Middle-Aged Women, Kathryn Suzanne Thomas

Theses and Dissertations

This study was conducted to determine the extent to which changes in dietary fiber consumption affect weight and body fat percentage (BF%) over time. An auxiliary objective was to examine the influence of age, total caloric intake, and physical activity (PA) on the relationship between changes in fiber intake and changes in body composition over time. Design/ Subjects: Prospective cohort design with baseline and follow-up assessments 20 months apart and 252 middle-aged women (40.1±3.0 y). Diet, particularly caloric and fiber intake, was measured using 7-day weighed food records. Body fat was assessed via the Bod Pod, and PA was measured …


The Effects Of The Front Squat And Back Squat On Vertical Jump And Lower Body Power Index Of Division 1 Male Volleyball Players, Manu Hoani Peeni Jun 2007

The Effects Of The Front Squat And Back Squat On Vertical Jump And Lower Body Power Index Of Division 1 Male Volleyball Players, Manu Hoani Peeni

Theses and Dissertations

The purpose of this study was to compare effects of the front squat and back squat on vertical jump and lower body power index of division 1 male volleyball players. Eighteen NCAA Division 1 male volleyball players volunteered for this study and were assigned either to a back squat or a front squat training program group. Subjects followed the training program for 8 weeks. Counter-movement vertical jump (CMVJ) height and lower body power index were measured at 0, 4 and 8 weeks of the study. A 2x3 factorial ANOVA revealed no significant difference in CMVJ height and power index between …


C-Reactive Protein Levels According To Physical Activity And Body Weight For Participants In The Coronary Health Improvement Project, Michael T. Massey Jun 2007

C-Reactive Protein Levels According To Physical Activity And Body Weight For Participants In The Coronary Health Improvement Project, Michael T. Massey

Theses and Dissertations

Objectives. Evaluate C-reactive protein (CRP) levels according to weight and physical activity. The study explored how changes in CRP were associated with baseline CRP, weight, and physical activity and changes in these variables.

Methods. A randomized controlled study design assigned 348 individuals to the intervention or control group with measurements taken at baseline, 6 weeks, and 6 months of body weight, physical activity, and serum CRP levels. Participants attended an intensive 40-hour educational course delivered over a four-week period.

Results. At baseline, CRP was negatively associated with total steps/week, and positively associated with weight, BMI, percent fat, and saturated fat …


Ground Reaction Force Differences Between Running Shoes, Racing Flats, And Distance Spikes In Runners, Suzanna Jean Logan Jun 2007

Ground Reaction Force Differences Between Running Shoes, Racing Flats, And Distance Spikes In Runners, Suzanna Jean Logan

Theses and Dissertations

To measure the differences in ground reaction forces between running shoes, racing flats, and distance spikes, twenty intercollegiate distance runners ran across a force plate at 6.7m/s (for males) and 5.74m/s (for females) in each of the three types of shoes. In order to control for differences in foot strike, only subjects who had a heel strike were included in the data analysis (N=16). Repeated-measures ANOVA and Tukey's post-hoc test (p<0.05) revealed loading rate and impact peak to be significantly increased in the flats and spikes compared to running shoes. Stiffness in spikes was significantly higher than in running shoes. Stance time in spikes and flats was decreased. These results can be used to better inform competitive runners, coaches, and trainers of the risks and performance benefits when determining the frequency and duration of the use of competitive footwear in training.


Emotional Health And Weight Gain: A Prospective Study Of Middle-Aged Women, Ann Bahr Jun 2007

Emotional Health And Weight Gain: A Prospective Study Of Middle-Aged Women, Ann Bahr

Theses and Dissertations

The objective of this study was to investigate the extent to which risk of gaining weight or body fat is affected by emotional health in women. A secondary objective was to determine the influence of age, baseline weight and body fat, physical activity (PA), energy intake, and changes in PA and energy intake, on the relationship between emotional health and gains in weight and body fat. The study was a prospective cohort investigation over 20 months of 256 healthy, non-obese females (age: 35-45 y, BMI < 30 kg/m2). All subjects were assessed for several variables using objective measurements at baseline and again at 20 months. Emotional health was assessed using the General Well-Being Schedule. Body fat percentage was indexed using the Bod Pod. PA was measured objectively using MTI (CSA) accelerometers, and energy intake was measured using weighed, 7-day food records. The results of the study demonstrated that risk of gains in weight and body fat were no greater in depressed women compared to their counterparts. However, 171 (66.8%) subjects demonstrated less than positive (LTP) emotional health at baseline, and 37.4% of these subjects gained weight during the 20-month study. Conversely, 85 (33.2%) subjects had positive emotional health at baseline, but only 23.5% gained weight over the investigational period. With no variables controlled, women with LTP emotional health had 59% greater risk of weight gain over the study period than women with positive emotional health (RR 1.59, 95% CI = 1.04-2.44). Women with LTP emotional health were at no greater risk of gains in body fat percentage than women with positive emotional health (RR 0.96, 95% CI = 0.70-1.33). After adjusting for each potential confounder individually, risk of gaining weight or body fat did not change. However, after adjusting for all of the potential confounders simultaneously, risk of weight gain was weakened (RR 1.43, 95% CI = 0.93-2.21). These results seem to demonstrate that middle-aged women with LTP emotional health may be at increased risk of gaining weight compared to women with positive emotional health.


Asymmetric Dihydroxylation And Aziridination Of Allenes And Related Chemistry, Renmao Liu May 2007

Asymmetric Dihydroxylation And Aziridination Of Allenes And Related Chemistry, Renmao Liu

Theses and Dissertations

A novel method for asymmetric synthesis of α-hydroxy ketone with excellent regio- and stereoselectivity has been established by the systematic investigation of asymmetric dihydroxylation of allenes. The efficiency of kinetic resolution of racemic allenes was also investigated by using the AD reaction on both 1,3-disubstituted and trisubstituted allenes. Steric effects, electronic effects and allene substitution are also discussed. Aziridines were formed by copper-catalyzed intramolecular nitrene addition to alkenes. The carbamate group was used as the tether between the alkene and the nitrene. Subsequent nucleophilic attack of the aziridine was accomplished using RSH, R2NH, N3-,or ROH as the nucleophile. This addition …


Towards Early State Disease Detection In Microdevices: Fabrication And Testing Of Micro Total Analysis Systems For Bioanalytical Applications, Tao Pan May 2007

Towards Early State Disease Detection In Microdevices: Fabrication And Testing Of Micro Total Analysis Systems For Bioanalytical Applications, Tao Pan

Theses and Dissertations

The past few years have seen a rapid expansion in interest in the characterization of the entire complement of proteins, or proteome. Micro total analysis systems (μTAS) are an emerging promising method, offering rapid, sensitive and low sample consumption separations. I have demonstrated microchip capillary electrophoresis (CE) devices made of CaF2. New methods have been developed for micromachining enclosed capillaries in CaF2. CE analysis of fluorescently labeled amino acids was used to illustrate bioanalytical applications of these microdevices. Initial on-chip infrared spectroscopy results for qualitative analyte identification were achieved in microfluidic CaF2 channels. I have also shown the evaluation of …


Effects Of Exposure To Perinatal Ultrasound Radiation On Information Processing In The Auditory System, Jennifer Burnett Apr 2007

Effects Of Exposure To Perinatal Ultrasound Radiation On Information Processing In The Auditory System, Jennifer Burnett

Theses and Dissertations

Ultrasound (US) has become a standard procedure used during pregnancy to document the health and development of a fetus. When ultrasound was first developed, some researchers urged caution, suggesting that the possibility of hazard should be kept under constant review. Given the routine application of fetal ultrasound imaging, any possibility of deleterious developmental effects resulting from its use is an important public health issue. Rats have a well characterized central nervous system whose neurochemical pathways and neuronal electrophysiology qualitatively correspond to those of humans. Because of this, we opted to use Wistar rats as an animal model to document effects …


An Infection Model For Examining The Effects Of Gender And Diabetic State On Proinflammatory Cytokine Secretion By Phagocytic Cells In Response To Infection With Burkholderia Pseudomallei, Laura L. Dickey Apr 2007

An Infection Model For Examining The Effects Of Gender And Diabetic State On Proinflammatory Cytokine Secretion By Phagocytic Cells In Response To Infection With Burkholderia Pseudomallei, Laura L. Dickey

Theses and Dissertations

Burkholderia pseudomallei is an opportunistic soil pathogen that causes melioidosis, a life-threatening human disease prevalent in Southeast Asia, northern Australia, the Middle East, Africa, and South America. The organism also causes disease in plants and animals. Persons with severe melioidosis usually die of septicemia. Relatively little is known regarding the virulence mechanisms of B. pseudomallei; however, several putative virulence determinants have been identified. The organism is able to invade and replicate within phagocytic cells and is particularly pathogenic in males with diabetes mellitus. B. thailandensis is closely related to B. pseudomallei, but is not pathogenic. This study examines various in …


Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu Apr 2007

Kinetic Studies Of 6-Halopurine Nucleoside In Snar Reactions; 6-(Azolyl, Alkylthio And Fluoro)-Purine Nucleosides As Substrates For Suzuki Reactions, Jiangqiong Liu

Theses and Dissertations

In chapter 1, we describe development of a mild and efficient method for SNAr iodination of 6-chloropurine 2'-deoxynucleosides and nucleosides. Our studies demonstrate that 6-iodopurine nucleosides are excellent substrates for certain transition metal-catalyzed cross-coupling reactions. In chapter 2, we describe synthesis of protected 6-fluoro, 6-chloro, 6-bromo and 6-sulfonylpurine nucleosides. Comparisons among 6-fluoro-, 6-chloro-, 6-bromo, 6-iodo and 6-sulfonylpurine nucleosides for SNAr reactions with various N, O and S nucleophiles were investigated. Our results demonstrate that the 6-fluoropurine nucleoside is the best substrate for SNAr reactions among the four 6-halopurine nucleosides with oxygen, sulfur and aliphatic amine nucleophiles, and also with an …


Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia Apr 2007

Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia

Theses and Dissertations

Nanomaterials display interesting physical and chemical properties depending on their shape, size and composition. Self assembly is an intriguing route to producing nanomaterials with controllable compositions and morphologies. DNA has been used to guide the self assembly of materials, resulting in: (1) metal nanowires; (2) metal or semiconductor nanorods; (3) carbon nanotubes; and (4) semiconductor, metal or biological nanoparticles. My work expands the range of DNA templated nanomaterials and develops novel ways of using DNA to pattern nanostructures on surfaces. I have performed the first synthesis of silver nanorods on single stranded DNA, an attractive material for localizing DNA coupled …


Investigation Of Novel Microseparation Techniques, Yansheng Liu Apr 2007

Investigation Of Novel Microseparation Techniques, Yansheng Liu

Theses and Dissertations

Ultrahigh pressure liquid chromatography (UHPLC) makes it possible to use very small particles (< 2 µm) as packing materials to provide high column efficiencies. Results from a careful comparison of small porous and nonporous particles show that when the particle size is small enough (< 2 µm), both porous and nonporous particles give excellent performance, and the differences in column efficiencies between porous and nonporous particles become insignificant. Columns packed with bare diamond particles could separate small molecules, especially polar molecules, however, severe tailing occurred for less polar compounds. The polybutadiene coated diamond particles gave greater retention and better separation of small molecules compared to bare particles, although no improvement in column efficiency was observed. Changes in surface bonding of thermally hydrogenated diamond particles was achieved by chemical modification using various organic peroxides with or without reagents containing long carbon chain functional groups. It appears that the alkyl groups were attached onto the diamond surface with limited coverage. LC experiments did not demonstrate good separation; however, changes in LC behavior were observed. A repetitive solvent programming approach was successfully applied to the analysis of a continuous sample stream in microbore LC. Each analysis cycle consisted of three steps: pseudo-injection, elution and rinse. In the pseudo-injection step, elution with a non- or poor-eluting solvent produced a concentrated sample plug due to on-column focusing. Factors influencing peak symmetry, resolution and analysis cycle length were investigated. Quantitative analysis of a continuous sample stream is possible under certain operating conditions. Electric field gradient focusing (EFGF) devices with distributed resistor substrates could focus proteins in the separation channel, however, the focused bands were not stable, and the repeatability was poor due to the formation of bubbles and pH gradient in the separation channel. Both fiber-based and porous glass capillary-based planar EFGF devices with changing cross-sectional area (CCSA) channels were constructed and evaluated with the aid of a home-made scanning laser-induced fluorescence detection system. The fiber-based CCSA EFGF devices gave poorer performance compared with glass capillary based devices. Porous glass capillary-based EFGF devices could focus single proteins and separate mixtures of two to three proteins.


The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke Mar 2007

The Role Of Phosducin-Like Protein As A Co-Chaperone With The Cytosolic Chaperonin Complex In Assembly Of The G Protein Βγ Subunit Dimer, Paul Jayson Ludtke

Theses and Dissertations

Phosducin-like protein (PhLP) has been shown to interact with the cytosolic chaperonin containing TCP-1 (CCT), and the βγ subunit dimer of heterotrimeric G proteins (Gβγ). Here we provide details obtained from cryo-electron microscopic and biochemical studies on the structure of the complex between the cytosolic chaperonin CCT and PhLP. Binding of PhLP to CCT occurs through only one of the two chaperonin rings, making multiple contacts with CCT through both its N- and C-terminal domains. In addition, we show that PhLP acts as a co-chaperonin along with CCT in mediating the assembly of the G protein βγ subunit and that …