Medicine and Health Sciences Commons^™

Disparate Degrees Of Hypervariable Loop Flexibility Control T Cell Receptor Cross-Reactivity, Specificity, And Binding Mechanism, Daniel R. Scott, Oleg Y. Borbulevych, Kurt H. Piepenbrink, Steven A. Corcelli, Brian M. Baker

Food for Health: Publications

αβ T cell receptors recognize multiple antigenic peptides bound and presented by major histocompatibility complex molecules. TCR cross-reactivity has been attributed in part to flexibility of the complementarity-determining region loops, yet there have been limited direct studies of loop dynamics to determine the extent of its role. Here we studied the flexibility of the binding loops of the αβ TCR A6 utilizing crystallographic, spectroscopic, and computational methods. A significant role for flexibility in binding and cross-reactivity was indicated only for the CDR3α and CDR3β hypervariable loops. Examination of the energy landscapes of these two loops indicated that CDR3β possesses a …

Constructive Developmental Theory: An Alternative Approach To Leadership, Anne Marie B. Hunter, Nancy M. Lewis, Paula K. Ritter-Gooder

Department of Nutrition and Health Sciences: Faculty Publications

As early as 1954, the critical value of leadership in dietetics was described by Rourke, who wrote, “When the day comes that your executive abilities equal your scientific knowledge, your profession (dietetics) will be secure. Until that day, you will be faced with a constant and unwelcome challenge” (1). Career and leadership skills development have been identified as an area for further attention by American Dietetic Association (ADA) practitioners and student members (2). Creation of the ADA Leadership Institute in 2003 represented an awareness of the need to invest in developing dietetic leaders (3). Proficient leaders are critical in keeping …

Perceived Importance And Actual Intake Of Calcium And Vitamin D In Young Female Athletes, Miriam E. Zambrano

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Calcium needs increase as a child grows. Actual intake often decreases as a child gets older, leaving his/her developing bones at risk for injury during childhood and increasing the risk of developing osteoporosis later in life. The purpose of this study was to investigate relationships between psychosocial factors influencing consumption of calcium and vitamin D-rich foods and actual intakes of these nutrients. We examined the dietary calcium and vitamin D intakes, determined serum vitamin D levels, and assessed nutrition knowledge and perception of a sample of 20 young girls participating in competitive cheerleading in Omaha, Nebraska. From this information we …

Effects Of Single Nucleotide Polymorphisms In The Human Holocarboxylase Synthetase Gene On Catalytic Activity, Shingo Esaki

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Holocarboxylase synthetase (HCS) catalyzes the covalent binding of biotin to carboxylases and histones in eukaryotic cells. Biotinylated carboxylases play essential roles in the metabolism of fatty acids, amino acids, and glucose; biotinylated histones play essential roles in gene regulation and genome stability. HCS null individuals are not viable whereas HCS deficiency is linked to developmental delays and phenotypes such as short life span and low stress resistance. Greater than 2,500 single nucleotide polymorphisms (SNPs) have been reported for HCS, but the biological importance of these polymorphisms is unknown. We hypothesized that some of these SNPs impair catalytic activity and that …

Intervention To Increase Knowledge And Consumption Of Folate-Rich Foods Based On The Health Belief Model, Lindsay M. Labrosse

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Folate is important in the prevention of birth defects and in the maintenance of general health. Even after mandatory fortification, many people are still not consuming the RDA of 400 mcg/day. Consuming a diet rich in naturally high-folate foods, as opposed to supplementation, may offer additional health benefits and promote an overall healthy diet.

The purpose of this pilot study was to test the hypothesis that a learner-centered educational intervention based on the Health Belief Model (HBM) will successfully increase knowledge and consumption of folate-rich foods, while increasing positive beliefs about folate and health. A two group parallel control trial …

Farm To School: A Case Study Of Four Rural Nebraska Schools Before Initiating Locally Grown Foods In School Food Service, Morgan Swisher

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

More than 25% of children in the U.S. are overweight. Farm to School is a program that encourages schools to procure local produce and nutrition education in an effort to improve childhood nutrition. A case study involving four schools has examined the attitudes of food service managers, food service staff members, and educators who are about to incorporate this program into their schools. Food service managers were interviewed about the foods they intend to purchase, food safety, menu planning, expected costs and receiving, additional training, and staff interest. From the qualitative study, the following themes were found: “More work for …

A New Single Workbout Test To Estimate Critical Power And Anaerobic Work Capacity, Haley Bergstrom

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

The purpose of the present study was to develop a new 3-min, single workbout test to estimate critical power (CP) and anaerobic work capacity (AWC) using the Monark cycle ergometer with the resistance based on the individual’s body weight. Twelve moderately-trained adults (6 men and 6 women; mean age ± SD = 23.2 ± 3.5 yr) performed an incremental cycle ergometer test to exhaustion. The CP and AWC were estimated from the original work limit (W_lim) versus time limit (T_lim) relationship (CP_PT) and a 3-min all-out test (CP_3min) against a fixed resistance …

Intent Of Expecting Fathers To Encourage Breastfeeding, Perceptions Of Support And Barriers To Encouraging Breastfeeding, Katrina Harwood

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Breastfeeding is well known to be the optimal feeding method for healthy infants. Although the benefits of breastfeeding have been well documented, according to the Centers for Disease Control (CDC) 2010 breastfeeding report card, breastfeeding rates at 3months, 6 months and 12 months post-partum have fallen below the objectives set by Healthy People 2010. A mother’s decision to breastfeed has been associated with a variety of factors including, income, education level, geographic location and level of breastfeeding support provided by health care professionals, her mother and the infant’s father. The father of the unborn child has been identified as being …

Identification And Engineering Of Human Variable Regions That Allow Expression Of Stable Single-Chain T Cell Receptors, David H. Aggen, Adam S. Chervin, Francis K. Insaidoo, Kurt H. Piepenbrink, Brian M. Baker, David M. Kranz

Food for Health: Publications

Single-chain antibody fragments (scFv), consisting of two linked variable regions (V_H and V_L), are a versatile format for engineering and as potential antigen-specific therapeutics. Although the analogous format for T cell receptors (TCRs), consisting of two linked V regions (Vα and Vβ; referred to here as scTv), could provide similar opportunities, all wild-type scTv proteins examined to date are unstable. This obstacle has prevented scTv fragments from being widely used for engineering or therapeutics. To further explore whether some stable human scTv fragments could be expressed, we used a yeast system in which display of properly folded …

Regulation Of Sterol Transport By Dietary Phytosterol Esters, Trevor J. Carden

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

LDL cholesterol is associated with the development of atherosclerosis and is therefore considered an important target for intervention to prevent cardiovascular diseases. The inhibition of cholesterol absorption in the small intestine is an attractive approach to lowering plasma cholesterol, one that is exploited by drug therapy as well as dietary supplementation with plant sterols. The mechanism of action of plant sterol esters (PSE) is still incompletely understood, therefore this study was conducted to test the hypothesis that hydrolysis of plant sterol esters is necessary for their cholesterol-lowering effects to be realized.

Male Syrian hamsters were fed diets containing no PSE, …

Content Validation Of A Standardized Language Diagnosis By Certified Specialists In Gerontological Nutrition, Paula K. Ritter-Gooder, Nancy M. Lewis, Kent M. Eskridge

Department of Nutrition and Health Sciences: Faculty Publications

Validation of the nutrition standardized language assures the language is accurate for use in practice, policy, and research, but few validation studies have been reported. The purpose of this descriptive study was to validate content of all components of the nutrition diagnostic term involuntary weight loss using experts providing care for older adults in health care settings. A Nutrition Diagnosis Validation Instrument was developed that contained the definition, etiologies, and signs and symptoms of the diagnosis plus items added from literature review. Questions on clarity and completeness of the language were included. The Nutrition Diagnosis Validation Instrument used a Likert-type …

Omega-3 Dietary Intakes, Knowledge, And Attitudes In Patients Screened For Colon Cancer, Cindy Kaminski

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Objective: The purpose of this study was to estimate Omega-3 (n-3) fatty acid intakes in colonoscopy patients and to examine knowledge and attitudes held about dietary fats.

Subjects/Methods: Men (n=32) and women (n=47) patients were recruited from a Midwestern gastroenterology clinic. A dietitian obtained informed consent, a food recall and response from a 152-item n-3 food frequency questionnaire (n-3 FFQ) at the clinic using visuals and food models. Two additional 24-h recalls, including a weekend recall, were returned by mail. A questionnaire measuring diet fatty acids knowledge, diet attitudes and beliefs was also obtained.

Results: Daily intake of n-3 fatty …

Preschool Children’S Willingness To Try And Preference For Docosahexaenoic Acid Omega-3 Foods, Bethany Joann Bettenhausen

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

During the preschool years, obesigenic eating habits are formed which are strongly associated with risk of developing chronic diseases later in life particularly cardiovascular disease. Docosahexaenoic acid (DHA) omega-3 fatty acid is a polyunsaturated fat with known benefits for heart health, brain cell structure, and retinal development. Current intakes of DHA are below recommended levels. United States (US) Midwestern children may be particularly at risk for suboptimal intakes of DHA. However, foods fortified with life’sDHA^TM, a product of Martek Biosciences and omega-3 eggs may provide culturally acceptable sources of DHA to Midwestern children.

Very little is known about …

Sensory Evaluation Of Ice Cream Made With Prebiotic Ingredients Substituted For Sugar, Jennifer M. Wood

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Prebiotics are non-digestible food ingredients that beneficially affect the host by selectively stimulating growth and/or activity of beneficial bacteria in the colon. The project objective was to determine consumer acceptability of ice cream with prebiotic ingredients substituted for part of the sugar and to determine sensory attributes of sweetness, smoothness, and vanilla flavor. A commercial ice cream mix was made substituting 0%, 10%, 20%, or 30% of the sugar for either Fructooligosaccharides (FOS) or inulin. Sensory analyses were conducted using 95 non-trained panelists. Overall consumer acceptability and sensory attributes were measured on a 175 mm anchored hedonic scale. When 10% …

Fluorine Substitutions In An Antigenic Peptide Selectively Modulate T Cell Receptor Binding In A Minimally Perturbing Manner, Kurt H. Piepenbrink, Oleg Y. Borbulevych, Ruth F. Sommese, John Clemens, Kathrynq M. Armstrong, Clare Desmond, Priscilla Do, Brian M. Baker

Food for Health: Publications

T cell receptor (TCR) recognition of antigenic peptides bound and presented by major histocompatibility complex (MHC) molecules forms the basis of the cellular immune response to pathogens and cancer. TCRs bind peptide/MHC molecules weakly and with fast kinetics, features which have hindered detailed biophysical studies of these interactions. Modified peptides resulting in enhanced TCR binding could help overcome these challenges. Further, there is considerable interest in using modified peptides with enhanced TCR binding as the basis for clinical vaccines. Here, we studied how fluorine substitutions in an antigenic peptide can selectively impact TCR recognition. Using a structure-guided design approach, we …

Tanning Predicts Bone Mass But Not Structure In Adolescent Females Living In Hawaii, Daniel L. Osborne, Connie M. Weaver, Linda D. Mccabe, George P. Mccabe, Rachel Novotny, Carol Boushey, Dennis A. Savaiano

Department of Anthropology: Faculty Publications

Objectives: To evaluate the relationship between facultative skin pigmentation, which predicts circulating levels of plasma 25-hydroxymitamin D, and several measures of bone mass and structure in a cross sectional sample of adolescent females living in Hawaii.

Methods: Our sample was composed of adolescent females (n = 94) living in Hawaii where seasonal sun exposure is minimal, and who self-identified as either white (n = 16) or Asian (n = 78). Bone mineral content (BMC) of the total body, the lumbar spine and the hip, and cross sectional area (CSA) and section modulus (Z) at the …

Correlation Of Omega-3 Fatty Acids Intakes With Acculturation And Socioeconomic Status In Midwestern Latinas, Karina R. Lora, Nancy M. Lewis, Kent M. Eskridge, Kaye Stanek-Krogstrand, Daryl A. Travnicek

Department of Nutrition and Health Sciences: Faculty Publications

Background: Low socioeconomic status (SES) and acculturation of Latino immigrants in the U.S. are linked to a decrease in diet quality. Methods: Interviews were conducted with 162 first-generation Latinas to examine the association of SES and acculturation with intake of omega-3 (n − 3) fatty acids. Each participant provided dietary intake by use of a validated n − 3 food frequency questionnaire administered twice, 4 weeks apart, three 24-h recalls, sociodemographic information and completed the 5-item Short Acculturation Scale. Results: Mean intakes of Total n − 3, α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (g/d) were …

Mechanisms Of Decreased Cholesterol Absorption Mediated By Phytosterols In The Intestinal Lumen, Andrew W. Brown

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Phytosterols and their fatty acyl esters have been known for decades to lower LDL cholesterol, making them powerful nutraceuticals in lowering cardiovascular disease risk. The mechanisms by which phytosterols lower cholesterol, though, have been incompletely characterized. Three studies were executed to examine three aspects of cholesterol and phytosterol interactions in the intestinal lumen. In the first study, the ability of pancreatic cholesterol esterase to hydrolyze phytosterol esters was examined. Pancreatic cholesterol esterase hydrolyzed phytosterol esters, but the rate of hydrolysis proved sensitive to the structures of both the sterol and ester components. In the second study, cholesterol micellarization was challenged …