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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.
111

Maternal dietary glucose restriction and its effect on amniotic fluid amino acid composition

Miniaci, Sandra A. January 1997 (has links)
Since glucose is an essential nutrient for normal fetal growth and development, the impact of reduced maternal dietary glucose supply, on amniotic fluid (amf) amino acid composition was investigated. Furthermore, this study investigated whether any resulting changes in the concentrations of amf amino acids could be predictive of fetal growth and metabolic status. Pregnant rat dams were fed isocaloric diets containing graded levels of dietary glucose (0, 12, 24 and 60%) and the amf amino acid content was analysed on gestational days (gd) 18.5 to 21.5. Carbohydrate restriction produced significant increases in the concentrations of amf isoleucine (on gd 21.5), tryptophan (on gd 18.5 and 21.5) and 3-methylhistidine (on gd 20.5 and 21.5). An interaction between diet and day of gestation modified amf taurine levels such that dams fed low carbohydrate diets showed significant increases in amf taurine as pregnancy progressed. Specific amf amino acids correlated with fetal growth parameters and fetal tissue glycogen reserves indicating the ability of amf composition to reflect fetal distress under conditions of compromised maternal nutritional status. A greater statistical predictability of amf constituents was obtained with fetal growth parameters than with fetal tissue glycogen reserves. These results suggest that amf amino acids are better predictors of fetal growth status than of fetal metabolic status.
112

Interactions between types and levels of dietary fiber and Heligmosomoides polygyrus (Nematoda) infection in mice

Sun, Yi, 1973- January 2001 (has links)
The objectives of this study were to determine the effect of different types and levels of dietary fiber on Heligmosomoides polygrus (Nematoda) in laboratory mice. BALB/c mice were randomly assigned to one of seven diets: no fiber, cellulose (5%, 10%, 20%), and pectin (5%, 10%, 20) and infected with H. polygyrus one week later. The length of intestine increased significantly with the concentration of pectin and was associated with longer villi, thicker mucosa and increased villus/crypt ratio. In contrast, changing concentration of cellulose had minimal effects on the gastrointestinal tract. More day 5 larvae were found in mice fed 20% pectin, but neither type nor level of dietary fiber affected worm survival or spatial distribution. An increase from 5% to 10% pectin increased per capita egg production both in vivo and in vitro, but a further increase to 20% pectin decreased per capita egg production in vivo to the low level seen in mice fed no fiber. However when the parasites from mice fed 20% pectin diet were cultured in vitro, they released very high numbers of eggs. Changing concentration of cellulose had no effect on parasite egg production in vivo or in vitro. Our study supports the hypothesis that pectin promotes the establishment and reproduction of Heligmosomoides polygyrus, and that this is closely related to the changes in gut morphology. Therefore we conclude that cellulose, not pectin, should be used to balance reduced content of macronutrients in studies on malnutrition and nematode infection.
113

The effect of low dietary zinc on outcome of primary and challenge nematode infections in mice /

Minkus, Tracy M. January 1990 (has links)
The effect of low dietary zinc on the survival and reproduction of an intestinal nematode (Heligmosomoides polygyrus) during both primary (Experiment 1) and challenge (Experiment 2) infections was investigated. Plasma zinc concentrations were significantly lower in mice fed a 5 ppm zinc diet (ZR), compared with control mice fed a 60 ppm zinc diet (C) in both experiments. There were no significant differences between ZR and C mice in any other zinc parameter or on worm burdens or worm fecundity in either experiment. Comparisons between the primary infection and the challenge infection did suggest a possible effect of calorie restriction on worm burdens. / Parasitic infection did, however, affect the host nutritional status. Spleen weight was significantly higher in infected mice in both experiments. In the challenge infection, both liver and spleen copper concentrations were significantly higher, and spleen iron concentration significantly lower in the infected mice. That these significant results were seen only in the challenge infection may suggest the role of the host immune response.
114

The evaluation of the nutritional outcomes of advanced nutritional care for the treatment of dysphagia in the elderly /

Germain, Isabelle. January 2001 (has links)
Undernutrition and dysphagia in the institutionalized elderly are well documented in the literature. However, the clinical efficacy of diets to treat dysphagia have not been established. To offer a better understanding of the textural characteristics of the new Sainte-Anne's Hospital (SAH) modified texture reformed foods, rheological evaluations were performed. Apparent viscosity, consistency coefficient, flow behavior index and yield stress values were calculated for the thickened beverages. Texture profile analyses were performed on the reformed foods. Secondly, to evaluate the impact of SAH's reformed foods on nutritional intake and weight, a 12-week clinical trial was undertaken. Dysphagic frail elderly subjects (n = 17) of a long-term care facility of Montreal were randomly assigned to receive SAH reformed foods or traditional care. The experimental group demonstrated a significant increase in nutritional intake resulting in significant weight gain. These findings suggest that dysphagic frail elderly could reach healthy weight when adequately fed.
115

Parenteral glutamine supplementation in neonates following surgical stress

Nolin, France. January 2000 (has links)
Our objective was to study the effect of GLN supplementation on whole body protein turnover, somatic growth and gastrointestinal tolerance to enteral feeding in neonates following surgical stress. We hypothesized that GLN in total parenteral nutrition (TPN) would (1) favor retention of lean body mass by reducing protein breakdown (PB) during the acute phase after surgery, (2) promote somatic growth, (3) decrease length of time to achieve full feeds. Protein turnover was measured in a double-blind randomized trial involving neonates admitted to the Neonatal Intensive Care Unit after major surgery. L-GLN (n = 6) was added to TPN at a dose of 200 mg/g of protein intake. Controls (n = 7) were isonitrogenous. Isotope studies were performed on Day 4 of TPN. Subjects were given a 4-hour primed constant intravenous infusion of L-[1-13C]-leucine and [15N2]-urea. In the GLN group, a 15% reduction in PB was measured (unpaired t-test, p < 0.05). There was a trend towards improved net protein balance which was statistically different from zero in the GLN group. There were no differences in somatic growth during TPN course and in the length of time to achieve full enteral feeds. Results suggest that early TPN supplemented with GLN has a beneficial sparing effect on protein metabolism in critically ill neonates after major surgical stress.
116

Comparison of physical activity practices and dietary habits of health club members and community controls in Khayelitsha, Cape Town.

Isaacs, Roshan. January 2007 (has links)
<p>Chronic diseases pose public health concerns globally with an increasing trend in developing countries. The development of interventions to minimize or prevent the burden associated with chronic diseases has therefore become a necessity. In 2002 the School of Public Health of the University of the Western Cape developed a health club intervention in Khayelitsha. This intervention focused on promoting healthy lifestyles, particularly improved diet and physical activity. The objectives of this study was to determine whether members were more physically active than non-members and to determine whether members made healthier dietary choices than non-members.</p>
117

Dietary intake, diet-related knowledge and metabolic control of children with type 1 diabetes mellitus, aged 6-10 years attending the paediatric diabetic clinics at Grey's Hospital, Pietermaritzburg and Inkosi Albert Luthuli Central Hospital, Durban, KwaZulu-Natal.

January 2007 (has links)
The aim of this study was to assess the dietary intake, diet-related knowledge and metabolic control in children with Type 1 Diabetes Mellitus between the ages of 6-10 years attending the Paediatric Diabetic Clinics at Grey’s Hospital, Pietermaritzburg and Inkosi Albert Luthuli Central Hospital, Durban, KwaZulu-Natal. This was a cross sectional observational study that was carried out in a total of 30 subjects out of a possible 35 subjects that qualified for inclusion in the study from both the Grey’s Hospital clinic (n=8) and IALCH clinic (n=22). The dietary intake was assessed in a total of 25 subjects using a three day dietary record (n=20) and a 24 hour recall of the third day of the record (n=16). Diet-related knowledge was assessed using a multiple choice questionnaire. Metabolic control was assessed using the most recent HbA1c and the mean HbA1c results over the previous 12 months from the date of data collection. Height and weight measurements were also carried out. Information on socioeconomic status and education status of the caregivers was obtained from 22 caregivers through follow-up phone calls. All measurements except for dietary intake were obtained from all subjects participating in the study. The mean percentage contribution of macronutrients to total energy was very similar to the International Society for Pediatric and Adolescent Diabetes (ISPAD) Consensus Guidelines (2002). The mean percentage contribution of macronutrients to total energy from the 3 day dietary records and the 24 hour recalls were as follows: carbohydrate (52% and 49%); sucrose (2% and 2%); protein (16% and 17%); fat (32% and 34%). Micronutrient intake was adequate for all micronutrients except for calcium and vitamin D which showed low intakes. The mean diet-related knowledge score for the sample was 67% with significantly higher scores in children older than 8 years of age. The latest HbA1c for the sample was 9.7% and the mean HbA1c over the previous 12 months from the date of data collection was 9.6%. There was a significant positive correlation between age of the participant and the latest HbA1c (r = 0.473; p=0.008) and a significant negative correlation between the education level of the caregivers and the latest HbA1c (r = - 0.578; p=0.005) and the mean HbA1c over 12 months (r = - 0.496; p=0.019). Significant differences were found between African and Indian children respectively for HbA1c, with higher values in African children. There was no correlation between BMI for age and latest HbA1c (r = 0.203, p=0.282) or mean HbA1c over 12 months (r = 0.101, p=0.594). Z score for BMI for age was also not correlated with latest HbA1c (r = 0.045, p=0.814) or mean HbA1c over 12 months (r = - 0.012, p=0.951). Children from the Grey’s Hospital Clinic were found to have higher HbA1c values (p=0.001) and lower diet-related knowledge scores as compared to the children from the IALCH Clinic (p=0.038). It should be noted that the ethnic and racial composition of the children attending these two clinics differed. In conclusion the macronutrient intake in this sample was found to be similar to the ISPAD Consensus Guidelines (2002) while calcium and vitamin D intakes were low. Overall this sample displayed good diet-related knowledge while metabolic control was found to be poor. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
118

Dietary protein deficiency modifies systemic and gut-associated immune responses in mice infected with Heligmosomoides polygyrus (Nematoda)

Ing, Rebecca Yat Loo, 1971- January 1998 (has links)
Protein deficiency may increase susceptibility to gastrointestinal (GI) parasitic infections, possibly as a result of impaired systemic and/or intestinal effector responses induced by downregulation of Th2 cytokines and/or upregulation of Th1 cytokines. To test this hypothesis, female BALB/c mice (n = 18/diet) were fed a control (24%), marginal (7%), or deficient (3%) protein diet and given a challenge infection with the GI nematode, Heligmosomoides polygyrus. The 3% mice had higher worm burdens at 1, 2 and 4 weeks post-challenge infection (pci), lower increases in serum IgE, reduced intestinal eosinophilia, and depressed mucosal mast cell proliferation and activation at 1 to 2 weeks pci. To determine whether these suppressed effector responses in the 3% mice were associated with altered spleen and mesenteric lymph node (MLN) cytokine profiles, cells were restimulated in vitro with parasite antigen and cytokine concentrations were measured. Deficient MLN cells secreted significantly less IL-4 and more IFN-gamma at 1--2 weeks pci than did control MLN cells. Deficient spleen cells also secreted more IFN-gamma at 2 weeks pci compared with control spleen cells. From RT-PCR analyses, the 3% mice also had lower IL-4 mRNA expression in spleen and MLN at 1--2 weeks pci. Our study supports the hypothesis that protein deficiency exacerbates the survival of a GI nematode parasite by decreasing IL-4 (Th2) and increasing IFN-gamma (Th1) early in the infection, leading to reduced gut and systemic Th2 effector responses.
119

Celery blackheart occurrence during growth as influenced by light quality and nutrition.

Guévin, José. January 1981 (has links)
No description available.
120

The influence of energy-restriction on accumulation of Heligmosomoides polygyrus (Nematoda) in outbred CD-1 mice in free-running arenas

Dare, Oluwayemisi Katherine January 2003 (has links)
The influence of energy restriction on the transmission dynamics of a direct life cycle nematode, Heligmosomoides polygyrus, within free-running arena Systems has to date remained unexplored. Indoor populations of CD-1 outbred mice were established for 12 weeks in arenas and fed either energy-suffi ci ent (ES) or energy-restricted (ER-20% réduction in metabolizable energy) diets. Infection was introduced to ail arenas following 3 weeks of diet treatment. Contrary to previous findings, the mice fed the ER diets compensated for the deficiency by increasing food consumption and thus, while early in the experiment energy restriction was evident, dietary effects were no longer observed after 6 weeks. Worm burdens, measured at 4 time points over the course of the experiment, were higher in mice fed the ES diets. Although mice fed the ER diets had greater contact with infected areas, the mice fed the ES diets increased the duration of behaviours that heighten ingestion of the parasite - self and allogrooming. Dietary effects on behaviour were observed only after infection was introduced and were more pronounced in the durations of individual bouts rather than in overall durations or time budgets. Nesting bouts were prolonged in mice in the ER arenas perhaps as a means of thermoregulation to counteract the combined effects of infection and energy restriction. The duration of exploratory bouts was also higher in the ER mice possibly due to an inability to receive or process information in their environment. Social interactions, predominantly involving sniffing, increased after infection was introduced, supporting the rôle of odour in communicating infection status in same-sex conspecifics. Together these results provide a more comprehensive ethogram of mice in a semi-natural setting and highlight those behaviours where adaptive plasticity allows response to dietary and infection stresses.

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