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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Effects of Transcutaneous Electrical Neural Stimulation at the Tibialis Anterior Muscle on Kinematic, & Kinetic Parameters of Gait Initiation in Parkinsonism

Unknown Date (has links)
In Parkinson's Disease (PD) the postural synergy use to begin the initial fall in the saggital plane during gait initiation has been shown degraded and/or altered from that of healthy populations. The exact mechanism behind this poverty in gait initiation is unknown. This research was designed to assess the possibility that the signal from the central nervous system is degraded due to the disease which effects the basal ganglia leading to a reduced excitation and inhibition of the tibialis anterior (TA) and soleus (SOL) muscles respectively. Parkinson participants were asked to initiate gait to three different conditions, TENS (transcutaneous electrical neural stimulation) at the TA, TENS at the arm, and auditory signaling. The premise behind this research is that by bilaterally increasing the force output at of the TA muscles through TENS stimulation during the early stages of gait initiation one should observe improvement in gait initiation parameters of those with the disease. Three of the nine research hypothesis were supported with restrictions. Significant increases in peak center of mass velocity, center of mass velocity at heel-off, and horizontal impulse were established between TENS at the leg and auditory signaling conditions. Administration of TENS at the TA during the anticipatory postural adjustment phase does increase certain gait initiation parameters significantly in individuals with PD. TENS at the TA may also create, in PD patients, an increased force output by other muscles used in gait initiation. Interestingly, individuals with PD do significantly increase their gait initiation velocities apparently without significantly increasing the Anterior/posterior center of foot pressure shift. This finding suggests that individuals with PD utilize different strategies for GI than healthy populations. / A Thesis submitted to the Department of Nutrition, Food, and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2003. / May 31, 2003. / Kinetic Parameters of Gait Initiation in Parkinson / Includes bibliographical references. / Tonya Toole, Professor Directing Thesis; Charles C. Ouimet, Outside Committee Member; Lynn Panton, Committee Member; John Bertram, Committee Member.
52

The Efficacy of Dried Plum in Modulting Biomarkers of Bone Turnover in Postmenopausal Women

Unknown Date (has links)
Previous studies from our lab suggest that dried plum may exert positive effects on biomarkers of bone turnover in animal studies and a short-term clinical trial. Dried plum is not only a rich source of vitamins, minerals and polyphenols, but has been reported as having high antioxidant properties that may be responsible in prevention of bone loss. The purpose of this study was to examine the effect of three-month dried plum consumption on the biomarkers of bone turnover in postmenopausal women. A total of 123 postmenopausal women experiencing mild bone loss and who were free of hormone replacement therapy were randomly assigned to consume either 100 grams of dried plum or a nutritional equivalence of dried apple for three consecutive months. Bone-specific alkaline phosphatase (B-SAP), osteocalcin (OC), tartrate-resistant acid phosphatase-5b (TRAP5b), and deoxypyridinoline (Dpd) were analyzed at baseline and after three months to test the effect of daily consumption of dried plum on bone turnover markers. Repeated measures (RM) multiple analysis of variance (ANOVA) followed by RM ANOVA were conducted to analyze the results. Findings of this study indicated no significant differences between the dried plum and dried apple groups when the data were analyzed considering treatment by time interaction. However, treatment by dried plum increased Dpd, while time decreased TRAP5b and increased OC in the dried plum group. The inconsistency between markers of resorption, Dpd and TRAP5b, as well as discrepancies between our findings and previous studies suggests that blood and serum markers cannot be used to predict the effect of dried plum on bone density unless bone mineral density (BMD) is measured as the end point variable that would require study duration of at least six months and preferably longer. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2010. / March 5, 2010. / Dried Plum, Bone, Women, Osteoporosis / Includes bibliographical references. / Bahram H. Arjmandi, Professor Directing Thesis; Maria Spicer, Committee Member; Gershon Tenenbaum, Committee Member.
53

Zinc Regulation of Neural Stem Cell Proliferation and Antidepressant Efficacy

Unknown Date (has links)
Changes in zinc homeostasis are strongly associated with abnormal brain function and a variety of neurological and neuropsychiatric disorders, including depression. It is hypothesized that the neurogenic potential of chronic antidepressant administration contributes to its therapeutic effects in depression. Thus, the goal of this work was to determine the extent to which zinc is needed for antidepressant drug induction of neural stem cell proliferation and differentiation. Human NTERA-2/D1 (NT2) cell culture, an established in vitro model system to study neuronal development, was utilized. Zinc deficiency impaired NT2 cell proliferation measured by the number of Ki67-positive cells. Treatment with fluoxetine or lithium did not result in a significant increase in cell proliferation rate. However, six-day treatment with these antidepressants had a stimulatory effect on NT2 cell differentiation revealed by immunofluorecent detection of the neuron-specific marker TuJ1. Furthermore, zinc deficient cultures treated with fluoxetine or lithium appeared to have a decreased expression of this neuronal marker. Taken together, these results suggest that the essential trace element zinc is needed for neuronal stem cell proliferation and differentiation. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2009. / July 2, 2008. / Antidepressants, Depression, Neurogenesis / Includes bibliographical references. / Cathy W. Levenson, Professor Directing Thesis; Jasminka Ilich-Ernst, Committee Member; Myra Hurt, Outside Committee Member.
54

The Effects of Static Stretching on Running Economy and Endurance Performance in Female Distance Runners during Treadmill Running

Unknown Date (has links)
Stretching has long been a component of the endurance athlete's warm-up routine. However, it has been shown that stretching can lead to decreased muscle stiffness and can be associated with decreased performance in force and power production. A recent study from our laboratory has shown that stretching was associated with a decrease in economy and endurance performance in trained men. PURPOSE: The purpose of this study was to investigate the acute effects of static stretching on running economy and endurance performance in trained women distance runners. METHODS: Twelve women (Height:159.4 7.4 cm; Weight: 54.8 7.2 kg; % body fat:19.7 2.8%; Age: 30 9 years) were recruited for the study and attended three laboratory sessions. On the first visit, anthropometric and maximal oxygen consumption (VO2max) (48.4 5.1 ml/kg/min) measurements were recorded. The second and third visits occurred during days 3-7 of the participants' menstrual cycle. Participants performed two sessions of 60-minute treadmill runs following a randomly assigned 18-minute static stretching protocol or 18 minutes of quiet sitting. The static stretching protocol consisted of four, 30-second repetitions of five different exercises designed to stretch the quadriceps, hamstrings, calves and gluteal muscles. During the first 30 minutes of the treadmill run (running economy), expired gases, heart rate, and rating of perceived exertion were recorded while the participant ran at 65% VO2max. During the final 30 minutes (endurance performance), distance covered, speed, heart rate, and RPE were recorded while the participant attempted to cover as much distance as possible. Repeated measures analyses were performed on the data. Significance was accepted at p < 0.05. RESULTS: Although there were significant increases in flexibility following the static stretching protocol (29.8±8.3 vs. 33.1±8.1 cm), there was no effect of stretching on VO2 (33.7±3.2 vs. 33.8±2.3 ml/kg/min), calorie expenditure (270±41 vs. 270±41 kcal), heart rate (157 10 vs. 160 12 bpm) or endurance performance (5.5 0.6 vs. 5.5 0.7 km). CONCLUSION: These findings indicated that stretching did not have an adverse effect on endurance performance in trained women, which is contrary to the findings of our previous study in men. This could mean the endurance performance decrements previously associated with stretching are not related to increases in flexibility in trained women. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2009. / April 6, 2009. / Endurance Performance, Static Stretching, Running Economy, Female / Includes bibliographical references. / Lynn Panton, Professor Directing Thesis; Jeong-Su Kim, Committee Member; David Eccles, Committee Member.
55

Evaluation of Monoclonal Antibody-Based Enzyme-Linked Immunosorbent Assays (ELISAs) for Tree Nuts and Peanut Detection

Unknown Date (has links)
Tree nut and peanut allergies affect up to 1.4% US population. Upon exposure, sensitive individuals may experience adverse reactions, including fatal anaphylaxis, to tree nut and peanut allergens. Currently, there is no cure for food allergies. Strict avoidance of the offending allergens is the best defense for sensitive individuals. Consequently, it is important to develop reliable assays for food allergen detection. Several commercial polyclonal antibody (pAb)-based immunoassays are available for tree nut and peanut detection. However, the pAb-based assays often exhibit lack of specificity and robustness. The objective of the current investigation was to evaluate sensitivity, specificity, and robustness of monoclonal antibody (mAb)-based sandwich enzyme-linked immunosorbent assays (ELISAs) for almond, cashew, hazelnut, pecan, and peanut detection. The tested ELISAs are sensitive (limit of detections and limit of quantifications < 10 ppm) and reproducible (intra- and inter-assay variabilities < 24%). The laboratory developed ELISA used a mAb (4C10) targeting a well-defined amandin epitope that is recognized by several almond allergic patients’ sera IgE. Compared to the MonoTrace assay, the mAb 4C10-based ELISA was comparable in assay sensitivity and was superior in assay specificity and recognition of a human allergy relevant epitope. The detection mAbs targeted antigens were stable and detectable in whole tree nut and peanut seeds subjected to autoclaving, blanching, frying, microwaving, and dry roasting. No cross-reactivity was observed in 156 food ingredients, each tested at 100,000 ppm except for the hazelnut kit (cross-reactive with pecan and English walnut) and the pecan kit (cross-reactive with English walnut and black walnut). Antigen recovery ranges for spiked and incurred food matrices were 81‒126% and 22‒161%, respectively. The assay results were in agreement with the allergen declaration of 180 tested commercial foods with the exception of one sample where undeclared hazelnuts were detected, two samples where undeclared pecans were detected, and one sample where declared pistachio was not detected. In conclusion, the mAb-based ELISAs are sensitive, specific, and robust for tree nut and peanut detection and quantification under the tested conditions. / A Dissertation submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester 2016. / June 28, 2016. / ELISA, food allergy, monoclonal antibody, peanut, tree nut / Includes bibliographical references. / Shridhar K. Sathe, Professor Directing Dissertation; John G. Dorsey, University Representative; Yun-Hwa P. Hsieh, Committee Member; Kenneth H. Roux, Committee Member.
56

Effects of Thermal Processing on Structure and Immunoreactivity of Amandin, Almond (Prunus dulcis L.) Major Protein

Unknown Date (has links)
Almonds are the number one tree nut produced in the U.S. and the number one consumed tree nut worldwide. Despite their economic, nutritional, and consumer value, almonds are among the top foods responsible for eliciting allergies in sensitive individuals. Amandin is the major storage protein and allergen in almond, accounting for roughly 70% of the total soluble protein content. Almonds are frequently subjected to heat processing prior to consumption which may potentially alter the structure and allergenic properties of amandin. The objective of this study was to determine how heat treatment influences the structure and immunoreactivity of amandin in thermally processed almond seeds. Whole Nonpareil almond seeds were subjected to autoclaving (121°C, 15 psi, for 15 and 30 min), blanching (94°C for 5 and 10 min), frying (191°C for 1 min), microwaving (1000 W for 1 min and 500 W for 3 min), and roasting (140 and 160°C for 30 min each; and 168 and 177°C for 12 min each). Processed seeds were ground and amandin was isolated from defatted almond flour using cryoprecipitation at 4°C. Soluble protein content was determined by the Bradford and Lowry methods. Immunoreactivity was assessed using enzyme-linked immunosorbent assay (ELISA), Western blot, and dot blot using two different murine monoclonal anti-amandin detection antibodies, 4C10 and 4F10. Structural changes were assessed using ultraviolet (UV) absorption and fluorescence spectroscopy. Results are reported as mean ± SEM and one-way ANOVA was performed to compare means for difference. Post hoc analysis was performed using Fisher’s least significant difference at p ≤ 0.05. ELISA immunoreactivity was assessed by the ratio (R) = signal at 50% maximum signal of processed sample/signal at 50% maximum signal of unprocessed control. The range of R values for the tested processed samples were 0.36 ± 0.02 to 1.54 ± 0.10* for 4C10 (LSD=0.26) and 0.37 ± 0.05* to 1.23 ± 0.17* for 4F10 (LSD=0.21). Western blots and dot blots were consistent with ELISA results. Second-derivative UV spectroscopy was used to quantify tertiary stuctural changes through the determination of derivative peak ratios between two successive peaks. The ratios ranged from 2.31 ± 0.44 to 5.67 ± 0.54. Relative fluorescence intensities (F/F0) ranged from 1.02 to 1.22. The immunoreactivity of amandin in processed almond seeds as assessed by ELISA, Western blot, and dot blot varied depending on the type of processing treatment undergone. While immunoreactivity decreased under certain conditions, it was never eliminated, indicating antigenic stability of amandin towards thermal processing. Under certain processing conditions, changes in second-derivative UV spectra and fluorescence intensity were observed suggesting the occurrence of heat-induced structural changes. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2016. / June 16, 2016. / Almond, Amandin, Immunoreactivity, Protein structure, Thermal processing, Tree nut allergy / Includes bibliographical references. / Shridhar K. Sathe, Professor Directing Thesis; John G. Dorsey, Committee Member; Qinchun Rao, Committee Member; Michael Roper, Committee Member.
57

Lectin Analyses of Soybean and Soybean Products

Unknown Date (has links)
Soybean allergies are one of top eight types of food allergies, affecting ~ 0.4% children and 0.3% adults in North America. Soybean agglutinin (SBA) protein, also known as soybean lectin, is both an allergen as well as an anti-nutrient that reducing the nutritional value of soybean and soybean products. The objective of this study was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis. A competitive ELISA was constructed and optimized by using rabbit anti whole soybean polyclonal antibodies (pAb) as primary Ab. The constructed competitive ELISA was validated to have LOD of 0.063 ng/ml of soybean lectin in all tested samples. The ELISA is reproducible and accurate as CVs of all ELISAs tested were less than 24% and the average recoveries were within 15% of the actual value, which demonstrating accuracy of the assay. However, further investigate is needed to evaluating CV of the assay. The validated ELISA method was able to detect and quantify the SBA in 20 soybean varieties and indicated that the natural variability of SBA is subject to the effects of genotype and environment. Moreover, the ELISA can detect the SBA content in thermal processed soybean, germinated soybean sprouts, and commercial soybean products. The results suggested that processing methods can affect soybean lectin immunoreactivity. Compare to the conventional hemagglutinating assay, ELISA is more sensitive and effective. In conclusion, the constructed pAb-based competitive ELISA provides an efficacious detection and quantification for the soybean lectin. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2016. / June 21, 2016. / Includes bibliographical references. / Shridhar K. Sathe, Professor Directing Thesis; Qinchun Rao, Committee Member; John G. Dorsey, Committee Member.
58

Immunodetection of Porcine Blood in Foods

Unknown Date (has links)
Justification: Different porcine blood proteins have been widely used as emulsifier, binder and/or colorant in processed foods. However, misusage of porcine blood ingredients, such as mislabeling and substitution, can cause religious objections, law violation, food safety and/or food quality decrease. These issues highlight the need of detecting unfavorable porcine blood in foods to fight food fraud. Porcine whole blood, plasma and blood cells can be applied individually or in combination as food additives. Therefore, the study was divided into two parts. The objectives of the part 1 is (1) to develop and characterize a monoclonal antibody (mAb) that is specific for porcine hemoglobin; (2) to develop an indirect competitive enzyme-linked immunosorbent assay (icELISA) that can detect porcine blood adulteration in foods. The objective of part Ⅱ is to characterize two mAbs which have the target protein in porcine plasma. Methods: In part Ⅰ, mAbs were developed using hybridoma technique and purified using immunoaffinity. Western blot was applied to verify the target protein; to study the mAb selectivity; and to study the effect of pH on storage stability (29 days at 4 °C) and thermostability (50 ºC, 100 °C and 121 ºC for 15 min) of target protein. Indirect non-competitive ELISA (inELISA) was performed to study antibody affinity and storage stability of target protein, and to choose the optimized condition for icELISA. Eventually, an optimized icELISA and extraction buffer was developed. The assay was validated by FDA Guidance for Industry. In part Ⅱ, immunoaffinity column was applied to isolate the target protein. The isolated proteins were sequenced. The immunoreactivity of target protein was verified using four commercial antibodies (anti-transferrin, anti-haptoglobin, anti-plasminogen and anti-C7). To further investigate the isoelectric point (pI) and disulfide information of target protein, two-dimensional gel electrophoresis and non-reducing SDS-PAGE were performed, respectively. Results: In part Ⅰ, mAb13F7 was chosen after screening test because it has the best selectivity to porcine blood. The target protein of the mAb was porcine hemoglobin (PHb) subunit (14 kDa). Although this mAb could cross-react with hemoglobin from bovine, horse and sheep, their hemoglobin band color intensity was much less than that of PHb according to Western blot. From inELISA and icELISA, this mAb showed a high immunoaffinity to PHb compared with bovine hemoglobin. The affinity constant of this mAb is in a nanomolar range, which can be considered as high-affinity antibody. As for thermostability, PHb can maintain the best molecular integrity and immunoreactivity at alkaline pH compared to acidic pH and neutral pH. During storage at 4ºC up to one month, PHb remained intact without any degraded peptides observed and the immunoreactivity did not change significantly (P > 0.05). Finally, a sample extraction buffer (12.5 mM NaHCO3 and 25 Mm NaCl) and an anti-PHb cELISA were developed. After assay validation, the optimized cELISA was PHb-specific and had a working range from 0.5 ppm to 1000 ppm. This assay was sensitive (limit of detection: 0.5 ppm) and reproducible with low inter- and intra- coefficient of variances (CVs < 15%). In part Ⅱ, the target protein was successfully isolated and its immunoreactivity has been confirmed. Target protein sequence was obtained. In total, four commercial antibodies were tested, neither of them showed similar band pattern as mAb19C5 and mAb16F9. The target analyte is still under investigation. Significance: The established icELISA assay in part Ⅰ can be used to detect trace amount of porcine blood in foods to fight food fraud. It also has the potential to be used in identifying diseased pork through determining residual hemoglobin concentration in pork. It is suitable for (1) government to enhance food regulation; (2) food industry to surveillance product quality; and (3) third party authority to certify halal/kosher foods or evaluate food authenticity. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the Master of Science. / Spring Semester 2017. / March 27, 2017. / Includes bibliographical references. / Qinchun Rao, Professor Directing Thesis; Shridhar K. Sathe, Committee Member; Timothy M. Logan, Committee Member.
59

Mouse Moloclonal Antibody Based Indirect Elisa for Soybean Lectin (Glycine max L.) Detection

Unknown Date (has links)
Soybeans (Glycine max. L), as one of the most widely grown crops, account for 90% of U.S. oilseed production. Despite their economic, nutritional, and consumer value, soybeans are among the top eight types of foods responsible for eliciting allergies in sensitive individuals. Soybean lectin is a tetrameric 7S protein with the binding specificity for GalNAc and Gal residues. It is one of the soybean allergens as well as an anti-nutrient that can cause reduced nutritional value of soybean and soybean derived food products. It is also a known toxicant able to agglutinate human red blood cells. Detection of soybean lectin in human and animal food supply is therefore important. The current available methodology for detection and quantification of soybean lectin rely on a variety of techniques that often lack specificity and sensitivity. The objective of this study was to obtain a validated method that is precise and accurate in the measurement of soybean lectin. A mouse monoclonal antibody based indirect ELISA was constructed for soybean lectin detection. Using low pressure column chromatography, soybean (certified seeds Hutcheson) lectin was purified. Using the purified soybean seed lectin, murine mAb 5A5 was produced and purified using Protein-G affinity column chromatography. Borate saline buffer, 0.1 M, pH 8.45 was used to solubilize proteins from petroleum ether defatted seed flour. Dot-blot and Western-blot immunoassays were used to screen mAb 5A5 for soybean lectin detection, specificity and sensitivity. Under the test conditions, the mAb 5A5 was specific for soybean lectin detection. The mAb 5A5, at concentration of 1520 ng/ml and 61 ng/ml, was able to detect 5 and 50 ng of the purified lectin, respectively, using dot- and Western- blot immunoassays. The mAb 5A5 detected the lectin in soluble soy proteins of 58 tested soybean seeds and 11 commercial soybean products using 1 and 10 microgram soy protein respectively for dot- and western blot immunoassays. No cross-reactive protein was found in 21 selected dry beans with mAb 5A5. Using purified murine anti-soybean lectin mAb 5A5 as detection Ab, a mouse monoclonal antibody based indirect ELISA demonstrated sensitivity, specificity, and reliability at trace levels. The indirect ELISA was validated to have LOD of 30 ng/ml (0.03 ppm), protein concentration at 50% máximum signal of 786.3ng/ml. This ELISA assay is reproducible and accurate with CVs <10% in intra- and inter-assay, and the average recoveries within 15% of the actual value. In conclusion, the indirect ELISA is sensitive, specific, and robust for the detection soybean lectin under the test conditions. / A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2018. / June 21, 2018. / Includes bibliographical references. / Shridhar K. Sathe, Professor Directing Thesis; Qinchun Rao, Committee Member; Michael Roper, Committee Member.
60

Kinetics and computer simulation of storage stability in intermediate moisture foods

Singh, Rakesh Kumar. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 199-229).

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