Background: Modifying the gut microbiota through the administration of probiotics during high fat feeding has been shown to attenuate weight gain and body fat accretion while improving insulin sensitivity in animal models. Objective: Our objective was to determine the effects of the probiotic VSL#3 on body weightand composition, skeletal muscle substrate oxidation, and insulin sensitivity and during 4 weeks of high-fat, hypercaloric feeding. We hypothesized that the probiotic would attenuate the body weight and fat gain and adverse changes in insulin sensitivity and substrate oxidation following high fat, hypercaloric feeding in young, non-obese males. Methods: Twenty non-obese males (18-30 y) volunteered to participate in the present study. Following a 2-week eucaloric control diet, subjects underwent a dual x-ray absorptiometry (DXA) to determine body composition, an intravenous glucose tolerance test (IVGTT) to determine insulin sensitivity, a skeletal muscle biopsy for measurement of substrate oxidation. Serum endotoxin was also measured. Subsequently, subjects were randomized to receive either VSL#3 (2 satchets) or placebo during 4 weeks of consuming a high fat (55% fat), hypercaloric diet (+1,000 kcal/day). Macronutrient composition of the high fat diet was 55% fat, 30% carbohydrate, and 15% protein. Results: There were no differences between the groups in subject characteristics or in the dependent variables at baseline. Body weight and fat mass increased less (P<0.045) following the high fat diet with VSL#3 compared to placebo. Insulin sensitivity (and other IVGTT variables) and both glucose and fat oxidation did not change significantly with time or VSL#3 treatment. Serum endotoxin concentration was not different between groups following the high-fat diet. Conclusions: VSL#3, a multi-strain probiotic, attenuated body weight and fat gain following a 4-week high fat, hypercaloric diet compared with a placebo. There were no differences between the VSL and control in circulating endotoxin, insulin sensitivity (and other IVGTT variables) or in skeletal muscle substrate oxidation. / Ph. D.

High-fat diets and obesity have been linked to unfavorable changes in gut bacteria and increased leakage of bacterially-derived lipopolysaccharide (endotoxin) from the intestinal tract into circulation, which is associated with low-grade inflammation, metabolic dysregulation and degradation of tight-junction proteins between intestinal cells. Probiotic supplementation is the practice of ingesting live strains of bacteria that are proposed to have a beneficial effect on the host by enriching the intestine with healthy bacteria. The purpose of this project was to determine if probiotic supplementation would prevent increased inflammatory tone, decreased oxidative capacity, and decreased tight-junction protein expression associated with high-fat feeding and elevated endogenous endotoxin. Male C57BL/6J mice were fed either a control (CD, 10% fat) or high-fat (HFD, 60% fat) diet for 4 weeks while receiving a daily oral gavage of water (C-VSL#3, HF-VSL#3) or probiotics (C+VSL#3, HF+VSL#3) equivalent to 1.2 billion live cultures. Changes in body weight, body composition, respiratory exchange ratio, energy expenditure, and glucose and insulin tolerance were measured in live mice. Markers of metabolic function were measured in whole muscle homgenates and mitochondria isolated from red and white skeletal muscle. Plasma endotoxin was measured in blood collected from fasted mice at the time of euthanization. The large and small intestines were collected and mRNA levels of tight-junction proteins and markers of nutrient sensing were measured. To determine a possible protective effect against endogenous LPS, a second cohort of mice were given an intraperitoneal injection of 0.1µg/kg LPS or saline to induce endotoxemia after four weeks of the aforementioned feeding protocol. Markers of metabolic function and inflammation were measured in mitochondria, skeletal muscle and liver. VSL#3 supplementation improved glucose homeostasis and markers of inflammation while enhancing nutrient sensing in the gut. / Ph. D.

It is thought that the peanut (Arachis hypogaea) originated in South America as peanuts have been found in the ancient burial graves in Peru. From South America they were carried to Arica and then to the United States with the slaves who came from Africa. It has been stated that when peanuts were placed in the hold of an old ship with the slaves, the slaves were in excellent physical condition on arrival for there was no beriberi. The peanut is perhaps the most important oil-bearing seed that is grown and its value as a source of oil has long been recognized. The Dutch buy peanuts from many countries and bring them to Rotterdam, where they crush the, into oil and meal, and barter these products to other countries. Much of their oil was formerly imported into the United States for here the peanut as a source of oil was not realized. Until a few years ago less than 8 percent of the crop was crushed for oil. However, 40 percent of the crop was used for oil in 1940. The “cake” or meal which is left after the oil has been expressed makes an excellent feed for cattle and is used as such to a great extent, particularly in Germany. During the first World War there was a great demand for peanut oil and today the need is felt again. It is stated in the Peanut Journal and Nut World (21) that peanut oil imports from foreign countries in the first six months of the 1940-1941 season decreased about 17 percent from the total reached during the same period of the previous years. Today the Secretary of Agriculture has called upon the peanut farmers of the nation to greatly expand their peanut acreage for the production of oil during the coming year. The goal for 1942 is 3,400,000 acres for peanut oil and 1,600,000 acres for edible use. In 1940 only one fourth of the crop of 200,000 tons of peanuts was used for oil. From each ton of peanuts approximately 600 pounds of oil can be obtained. Peanut oil is used in the United States mainly as an adulterant of or as a substitute for olive oil. It is so excellent in quality that most people cannot detect the difference. Peanut oil is mixed with nearly all the olive oil that comes from the United States. Peanut oil can replace, in part at least, the approximate 10,000,000 pounds of coconut oil that until now has been imported into the country for roasting peanuts, making soap and other uses. Since peanut production has been greatly increased for edible oil, and since so little research has been done on the culinary properties of the oil, a study of these properties seemed advisable. The primary purpose of this experiment was to study the palatability of potato chips, shoestring potatoes and French friend potatoes when fried in peanut oil as compared with those friend in cottonseed oil. The absorption of the oil by the products fried in peanut oil was compared with those fried in cottonseed oil. The changes in the two oils during repeated fryings was compared. These changes were measured by the smoking point, free acidity, and rancidity changes of the oils. Since the oils for this experiment could not be produced under experimental conditions, certain constants were measured in order to know about the qualities of the oils. These included the iodine number, saponification number, free acidity, smoking point and the resistance of the oils to rancidity changes. / Master of Science

Insulin resistance (IR), T2DM, and obesity together form a cluster of interrelated metabolic challenges that may be linked by metabolic inflexibility. Metabolic inflexibility is characterized by the resistance to switching substrate oxidation preference based on substrate availability and can be measured in either fasted or insulin-stimulated conditions. As the largest site for glucose disposal and a primary tissue influencing regulation of blood glucose concentrations, skeletal muscle likely plays a central role in regulating substrate oxidation preference based on substrate availability. Skeletal muscle lipotoxicity caused by an impaired regulation of fat uptake and oxidation is postulated to disrupt insulin signaling and lead to skeletal muscle IR. High dietary saturated fat intake results in reduced basal fat oxidation and a resistance to switching to carbohydrate oxidation during insulin-stimulated conditions in susceptible individuals. This metabolic inflexibility may lead to an accumulation of intramyocellular species that impair insulin signaling. Endurance exercise training improves the capacity for fat oxidation in metabolically inflexible individuals. However, relatively little is known about how endurance exercise training influences substrate oxidation preference when paired with a high fat diet (HFD). Therefore, the purpose of this study was to determine the effects of a HFD on substrate metabolism in skeletal muscle of sedentary and endurance trained (ET) males. Healthy, sedentary (n=17) and ET (n=7) males first consumed a 10-day moderate carbohydrate diet (55% carbohydrate, 30% total fat, <10% saturated fat) isocaloric to their individual energy requirements and then underwent a 4- hour high fat challenge testing session. During the session, they consumed a high fat meal (820 kcals; 25% carbohydrate, 63% total fat [26% saturated fat]), and skeletal muscle biopsies were taken in the fasted and 4-hour postprandial conditions. Participants then consumed a 5-day HFD (30% carbohydrate, 55% total fat, 25% saturated fat) and repeated the high fat challenge testing session. Substrate oxidation measures were performed on the collected skeletal muscle tissue, and the meal effect, defined as the percent change from the fasting to 4- hour postprandial condition, for each measure was calculated. There was a HFD by physical activity group interaction on meal effect for metabolic flexibility (P<0.05) and a HFD effect on meal effect for glucose oxidation (P<0.05). Meal effects for metabolic flexibility and glucose oxidation were maintained in the ET (20 ± 4% to 41 ± 21% and 128 ± 92% and 41 ± 15%, respectively; both P>0.05) but decreased in the sedentary (34 ± 7% to 4 ± 5% and 78 ± 26% to -21 ± 6%, respectively; both P<0.01) group. There were trends toward HFD effects on reductions in meal effects for total (P=0.062) and incomplete (P=0.075) fat oxidation, which were driven primarily by an increase in fasting total (12.1 ± 2.6 nmol/mg protein/h to 18.5 ± 2.3 nmol/mg protein/h; P<0.01) and incomplete (11.5 ± 2.5 nmol/mg protein/h to 17.6 ± 2.3 nmol/mg protein/h; P<0.01) fat oxidation in the ET group as a result of the HFD. Fasting total and incomplete fat oxidation did not change in the sedentary group (7.3 ± 0.8 nmol/mg protein/h to 7.8 ± 0.8 nmol/mg protein/h and 6.8 ± 0.7 nmol/mg protein/h to 7.2 ± 0.8 nmol/mg protein/h, respectively; both P>0.05). Overall, these findings suggest the ET state attenuates deleterious effects of a short-term HFD on reduced metabolic flexibility and insulin-stimulated glucose oxidation. In addition, a HFD-induced reduction in fat oxidation during the fasted-to-fed transition may be caused by differing mechanisms in sedentary and ET individuals. These findings provide a basis for future work targeting the elucidation of potential mechanistic differences in substrate oxidation preference between sedentary and ET individuals. / Ph. D. / Type 2 diabetes (T2DM) is a commonly occurring disease worldwide, and treatment of the disease is considerably burdensome for individuals and societies. T2DM is closely related to insulin resistance (IR) and obesity, and in each of these conditions, the characteristic of metabolic inflexibility has been observed. Metabolic inflexibility is a reduced ability to adjust fat or carbohydrate utilization for energy based on the availability of each of these macronutrients. Skeletal muscle may be an important tissue in the regulation of macronutrient utilization since it plays a key role in blood glucose regulation. High dietary saturated fat intake may lead to metabolic inflexibility in skeletal muscle in susceptible individuals. This metabolic inflexibility may result in increased storage of fat within skeletal muscle, which is hypothesized to disrupt insulin signaling. This disruption can lead to IR. Endurance exercise training improves metabolic flexibility. However, little is known about how endurance exercise training influences macronutrient utilization when paired with a high fat diet (HFD). Therefore, the purpose of this study was to determine the effects of a HFD on macronutrient utilization in skeletal muscle of sedentary and endurance trained (ET) males. Seventeen healthy, sedentary males and seven ET males first consumed a 10-day moderate-carbohydrate diet that was provided by the study investigators and designed to keep each participant weight stable. Participants then underwent a high fat challenge testing session in which they consumed a high fat meal and had skeletal muscle biopsies taken both before and after the meal. Participants then consumed a 5-day HFD, also designed to keep them weight stable, and repeated the high fat challenge testing session. Macronutrient utilization measures were performed on the collected skeletal muscle samples. Overall, metabolic flexibility was reduced in the sedentary group but was maintained in the ET group, which suggests that ET individuals may be protected against developing a HFD-induced metabolic inflexibility in skeletal muscle and its associated downstream negative effects on insulin signaling. In addition, fat utilization during the high fat challenge meal decreased in both sedentary and ET individuals as a result of the HFD. However, fat utilization in the fasted state was higher in ET individuals after the HFD compared with baseline, but fat utilization was the same in sedentary individuals before and after the HFD. This suggests there may be differences between sedentary and ET individuals in the mechanisms involved in the adjustment of fat utilization to dietary fat intake. Further research is needed to understand these differences, as they may play important roles in understanding how IR and T2DM develop.

Aedes aegypti is the primary vector for dengue, zika, chikungunya, and yellow fever viruses. Disease transmission through this mosquito places over 40% of the world's population at risk of contracting one or more of these pathogens. Current control strategies such as insecticide application have failed or carry additional burdens, such as off-target toxicity to mammals and birds. Our lab proposes utilizing a conserved arthropod hormone pathway, juvenile hormone (JH), related to growth and reproduction to curb these vector populations and reduce disease transmission. Additionally, JH is nontoxic to birds and mammals; it requires incredibly high doses to have lethal effects. We hypothesize that JH-responsive genes expressed early in the adult are responsible for her reproductive capacity and by manipulating the signaling downstream of the receptor, we will be able to decrease the female's fecundity and limit vector populations. Via bioinformatics screening of RNA-sequencing data using the New Tuxedo pipeline, we identified 47 potential transcription factor candidates. With the use of in vitro culturing of the mosquito's reproductive tissues in the presence of a translation inhibitor, we identified two early JH responsive gene candidates, FoxA and zinc finger 519, p-value <0.05. The functional characterization of these two remains to be seen, however, in Drosophila melanogaster, they both have roles in chromatin remodeling and require protein partners to carry out long range interactions. / Master of Science in Life Sciences / The mosquito, Aedes aegypti, is responsible for the spread of a myriad of viruses such as dengue, zika, and chikungunya. Currently, these infections have no vaccine or treatment available and transmission rates continue to steeply rise in response to the spread of breeding grounds. Popular insecticides carry detriments such as off-species toxicity and continuous application to treatment areas. Our lab proposes an alternative to these chemical insecticides by manipulating a developmental pathway in the mosquito. The Juvenile Hormone pathway is conserved in arthropods, responsible for growth and reproduction, and the hormone is nontoxic to mammals. Through the combination of bioinformatics and genomics studies, we have identified two JH-responsive gene candidates that are potential regulators of this pathway.

Yes / Introduction : Rheumatoid arthritis (RA) affects 1% of the population and is principally associated with joint inflammation. It is suggested however that muscle involvement may be one of the earliest clinical features of RA. It is therefore important that techniques exist to accurately assess muscle health in those with RA to enable successful treatment. This study assesses the inter-rater and intra-rater repeatability of Diffusion Tensor MRI (DTI), 2-Point Dixon fat fraction, and T2 relaxation of the thigh muscle in patients with RA using manual regions of interest (ROI). Methods: Nineteen patients (10/19 males; mean age 59; range 18-85) diagnosed with RA had an MRI scan of their hamstrings and quadriceps muscles to obtain fat fraction (FF), mean diffusivity (MD), fractional anisotropy (FA), and T2 quantitative measurements. Two raters (R#1 & R#2) (initials removed for review) independently contoured ROIs for each patient. R#1 repeated the ROI for the same 19 patients after a 6-month hiatus to assess intra-rater repeatability. Inter-rater and intra-rater repeatability for the ROI measurements were compared using Inter Class Correlation (ICC) and Bland-Altman plots. Results: There was excellent agreement for both inter-rater and intra-rater repeatability. ICC results ranged from 0.900-0.998 (P<0.001), and intra-rater ICC results ranged from 0.977-0.999 (P<0.001). Bland-Altman plots also showed excellent agreement. Conclusions: ICC measurements and Bland-Altman plots showed excellent repeatability and agreement with no statistically significant differences when assessing the inter-rater and intra-rater repeatability of FF, MD, FA, and T2 relaxation of the thigh muscle using manual regions of interest in patients with RA. Implications for practice: Manual ROI drawing does not introduce significant errors obtaining FF, MD, FA, and T2 MRI measurements in an RA population. / This research is funded by the NIHR infrastructure at Leeds.

Eight mature Arabian horses were assigned randomly to two groups. The two groups were fed either a control diet or a diet similar in which 10 % corn oil was substituted for cracked corn after a baseline SET. Horses were interval trained in a climate controlled barn 4 days per week on a high speed equine treadmill at a slope of 6 %. An SET was performed at 0, 6 and 11 wk of training. The horse walked at 1.6 m/s, then speed was increased every 3 min until the horse showed signs of fatigue. Blood samples were taken every 3 min prior to each speed increment and analyzed for glucose, lactic acid, cholesterol, triglycerides, total protein, and muscle glycogen. Muscle biopsies were taken before and after exercise and analyzed for glycogen. Lactate and glucose were plotted against speed and fitted to a broken line model. Resulting parameters were tested for significance by analysis of variance. Diet had an effect in SET 3 and SETs 2 and 3 combined, but not SET 2 alone. There were 3 effects of the fat diet on the lactate curve. The high fat diet tended to increase the lactate threshold (x-intercept at point of inflection) during SET 3 (P = 0.16) and SETs 2 and 3 combined (P = 0.08). Lactate threshold ranged from 3.88 to 6.53 m/s. The high fat diet also increased the plasma lactate level prior to the lactate threshold (y intercept) during SET 3 (P = 0.11) and SETs 2 and 3 (P = 0.10). The third effect was an increase in slope after the point of inflection in SET 3 (P = 0.03). Training increased the lactate threshold from 4.77 ± 0.22 m/s in SET 2 to 5.82 ± 0.22 m/s in SET 3. Plasma glucose and lactate concentrations were correlated (R² = 0.848, P < 0.0001). Mean values for SET 2 and 3 combined were 4.42 ± 0.29 and 5.09 ± 0.20 m/s for glucose and lactate thresholds, respectively, in the control group, and 4.13 ± 0.33 and 5.50 ± 0.23 m/s, respectively, in the fat group. There was a strong diet * speed interaction for triglycerides (P < 0.0001). Cholesterol tended to be higher in the high fat group during SET 3 (P = 0.15). Muscle glycogen decreased with exercise, however there was no significant difference between diets. These results show that full metabolic adaptation to a high fat diet was achieved in 11 wk but not 6 wk. The higher speeds of the lactate thresholds with both training and high fat diet were small but consistent. / Master of Science

Assessment methods are continually updated to adequately measure dietary intakes. Rapid Assessment Methodologies, or RAMs, are being developed to quickly measure specific nutrients. Although no perfect measure of an individual’s diet exists, diet records (DRs) are considered the most accurate assessment technique. The goal of this research was to design a short form using the frequency of consumption to detect clientele with high dietary fat intake. A food frequency questionnaire (FFQ) of 24 foods was developed based on data from national sources and on data on college students. College student FFQ ratings were compared with three-day DRs to determine the foods predicting the fat in their diet. Two RAMs, Fat Factor Short (FF Short) and Fat Factor Long (FF Long) were designed: FF Short (a shortlist of six foods) and FF Long (a longer list of 12 foods). FF Short was the preferred predictor of students consuming a high-fat diet. Short food lists should be useful in predicting dietary fat intake and assist in detecting individuals requiring further educational programs on reducing dietary fat. / Master of Science

N-Flate™ and a sweetening system of 1.5% aspartame, 35.5% fructose, and 63% polydextrose (AFP) were evaluated for their potential as fat and sugar substitutes, respectively. Four cupcake variations were prepared to compare the effects of replacing shortening with N-Flate™, and sugar with AFP. The four variations were shortening/sugar, shortening/AFP, N-Flate™/sugar, and N-Flate™/AFP. The evaluation involved objective measurements of the batter and the baked cupcakes, and sensory evaluation of the cupcakes. Results of the objective measurements showed that the batter from the two variations prepared with N-Flate™ had a Significantly higher pH and specific gravity than the two variations prepared with shortening. A lower cake volume, a firmer texture, a higher moisture content, and a darker crumb color were also observed in the two variations prepared with N-Flate™. The batter from the two variations prepared with AFP also had a higher pH and specific gravity than the two variations prepared with sugar. A lower cake volume, a firmer texture, a higher moisture content, and a lighter crust color were also observed in the two variations prepared with AFP. Among the objective measurements, interaction effects were significant for specific gravity, volume, crust color and tenderness. Sensory evaluation results showed that the two variations prepared with N-Flate™ were less tender and have poorer cell uniformity than those prepared with shortening. Variations prepared with AFP were found to be less moist, have a more bitter crust and crumb, and better cell uniformity than those prepared with sugar. No interaction effects were observed for any of the sensory attributes. / Master of Science

Total and differential leucocyte counts were made on 30 college women of ages of 18 to 28 years. / Master of Science