Effect of exercise and different environmental conditions on appetite, food intake and the appetite-regulatory hormones, ghrelin and peptide YY

The role of gut hormones in the regulation of appetite and food intake is well established. The studies presented within this thesis have examined the effects of exercise and different environmental conditions on gut hormones (acylated ghrelin and total peptide YY), appetite and food intake. Forty-two young (mean ± SEM; 22.6 ± 0.4 y), healthy and generally lean (body mass index 23.7 ± 0.3 kg m2) males were recruited into four studies. In study one, 60 minutes of high intensity (70 % of O2 max) running and cycling exercise suppressed concentrations of the appetite-stimulating hormone acylated ghrelin to a similar extent. Study two revealed that after 60 minutes running in the heat (30 °C), hunger is lower in the pre-prandial period, and energy intake lower over the 7 h trial duration compared with a similar trial conducted in temperate (20 °C) conditions. Acylated ghrelin was suppressed during running in the temperate and hot environment but this did not appear to mediate the lower energy intake observed during the hot trial. In study three, energy intake tended to be higher after 60 minutes running in a cool environment (10 °C) compared with a temperate (20 °C) environment. During and shortly after running in the cold, perceived ratings of fullness and satisfaction were lower. Acylated ghrelin concentrations appeared to be suppressed to a lesser extent during running in the cold which could mediate the elevated energy intake observed at the first meal. However, energy intake was also higher at the second meal in the cold trial when acylated ghrelin concentrations were higher in the temperate trial. Study four showed that energy intake and acylated ghrelin concentrations were lower, and total PYY tended to be lower, in normobaric hypoxia suggesting a possible role for acylated ghrelin, but not PYY, in mediating the decrease in energy intake observed in hypoxia. This thesis confirms that exercise transiently suppresses acylated ghrelin concentrations regardless of the environmental conditions (temperature and altitude) exercise is performed in. The findings support anecdotal reports that appetite and energy intake are suppressed in the heat and stimulated in the cold. These responses may be partly mediated by acylated ghrelin immediately after running but other mechanisms are likely involved thereafter. Acute hypoxic exposure suppresses acylated ghrelin concentrations; an observation which may explain the decreased energy intake in hypoxia

The development of goat and sheep herding during the Levant1ne Neolithic

This thesis examines the development of goat and sheep herding in the Levant during the Neolithic period, and focuses particularly on the emergence of caprines as major early domesticates and the development of specialised pastoral economies. It is divided into two sections. The first consists of a critical review of published palaeoclimatic, archaeological, archaeobotanical and zooarchaeological data, which are integrated to provide baseline interpretations of caprine domestication and the development of specialised pastoral economies. The second section presents the results of a zooarchaeological analysis of the faunal assemblage from the Neolithic site of 'Ain Ghazal, located in the Jordanian Highlands, which are evaluated in the context of the two baseline interpretations presented in the first section. The relative merits of the different methods by which archaeological caprine remains can be identified to species are also discussed. It is argued that goats were probably first domesticated in or immediately adjacent to the Lebanon and Anti-Lebanon Mountains during the 10th millennium b.p., and that mouflon were probably first domesticated in the piedmont zones of the Taurus and Zagros Mountains during the first half of the 9th millennium b.p.. The independent domestication of goats in the Zagros Mountains during the first half of the 9th millennium b.p. is regarded as a strong possibility. It is concluded that the concepts of there have been a temporal gap between the appearance of the earliest permanent agricultural villages and the earliest domestic caprines, and that significant periods of loose-herding preceded the full domestication of these species, may need to be reconsidered. Pastoral economies during the Levantine Neolithic seem to have been based on sedentary animal husbandry aimed at subsistence-orientated meat production. There is however some evidence that simple forms of distant pastures husbandry, still focused on subsistenceorientated meat production, may have developed during the Neolithic period

Effect of ambient temperature during acute aerobic exercise on short-term appetite, energy intake, and plasma acylated ghrelin in recreationally active males

Ambient temperature during exercise may affect energy intake regulation. Compared with a temperate (20 °C) environment, 1 h of running followed by 6 h of rest tended to decrease energy intake from 2 ad libitum meals in a hot (30 °C) environment but increase energy intake in a cool (10 °C) environment (p = 0.08). Core temperature changes did not appear to mediate this trend; whether acylated ghrelin is involved is unclear. Further research is warranted to clarify these findings

Renal Arterial Doppler Resistive Index in Differentiating Obstructive and Non-Obstructive Hydronephrosis in Children at Tikur Anbessa Specialized Hospital, Ethiopia, October, 2018

BACKGROUND: Most congenital anomalies of the urinary tract present with hydronephrosis. Some are physiological while others pathological. Ultrasound, micturating cyst urethrography, dynamic renal scintigraphy, intravenous urography, dynamic and static magnetic resonance urography are used for examination. Currently, renal arterial Doppler resistance index is used as complimentary mechanism. This study assesses our experience in resistive index measurement in differentiating obstructive from non-obstructive hydronephrosis in children.METHODS: A cross-sectional study of forty-two infants and children (<14 years) with hydronephrosis were enrolled using consecutive sampling. Ultrasonography to assess the degree of hydronephrosis and avoiding cystourethrogram were used for the diagnosis of vesicoureteral reflux and posterior urethral valve. Intravenous urogram and surgery were used to confirm causes for obstructive hydronephrosis. Doppler ultrasonography assessed both kidneys to determine mean resistive index for both obstructive and non-obstructive hydronephrosis as well as nonobstructive kidneys. Independent t test was used for analysis at p< 0.005.RESULTS: The major cause for obstructive hydronephrosis was pelviuretheric junction obstruction (47.6%) followed by posterior urethral valve (16.7%). For non-obstructive hydronephrosis, vesicoureteral reflux was the main cause followed by prune belly syndrome. The mean resistive index for non-hydronephrotic kidneys was 0.6654 ±0.053, for nonobstructive hydronephrotic ones was 0.6825 ± 0.06668 and obstructive ones was 0.7791 ± 0.11977. The mean resistive index difference between the obstructive and non-obstructive hydronephrosis was 0.09661 with standard error of difference 0.02443. The difference was statistically significant (P-<0.001). A mean RI ROC curve showed sensitivity,specificity and accuracy of 71.1%, 81.2%, 75.4% respectively (p=0.003).CONCLUSION: This study has shown that the mean renal arterial resistive index was significantly higher in obstructive hydronephrotic kidneys than non-obstructive hydronephrotic kidneys. This can be a valuable tool for diagnosis and follow-up after intervention

Effect of exercise and different environmental conditions on appetite, food intake and the appetite-regulatory hormones, ghrelin and peptide YY

The role of gut hormones in the regulation of appetite and food intake is well established. The studies presented within this thesis have examined the effects of exercise and different environmental conditions on gut hormones (acylated ghrelin and total peptide YY), appetite and food intake. Forty-two young (mean ± SEM; 22.6 ± 0.4 y), healthy and generally lean (body mass index 23.7 ± 0.3 kg m2) males were recruited into four studies. In study one, 60 minutes of high intensity (70 % of O2 max) running and cycling exercise suppressed concentrations of the appetite-stimulating hormone acylated ghrelin to a similar extent. Study two revealed that after 60 minutes running in the heat (30 °C), hunger is lower in the pre-prandial period, and energy intake lower over the 7 h trial duration compared with a similar trial conducted in temperate (20 °C) conditions. Acylated ghrelin was suppressed during running in the temperate and hot environment but this did not appear to mediate the lower energy intake observed during the hot trial. In study three, energy intake tended to be higher after 60 minutes running in a cool environment (10 °C) compared with a temperate (20 °C) environment. During and shortly after running in the cold, perceived ratings of fullness and satisfaction were lower. Acylated ghrelin concentrations appeared to be suppressed to a lesser extent during running in the cold which could mediate the elevated energy intake observed at the first meal. However, energy intake was also higher at the second meal in the cold trial when acylated ghrelin concentrations were higher in the temperate trial. Study four showed that energy intake and acylated ghrelin concentrations were lower, and total PYY tended to be lower, in normobaric hypoxia suggesting a possible role for acylated ghrelin, but not PYY, in mediating the decrease in energy intake observed in hypoxia. This thesis confirms that exercise transiently suppresses acylated ghrelin concentrations regardless of the environmental conditions (temperature and altitude) exercise is performed in. The findings support anecdotal reports that appetite and energy intake are suppressed in the heat and stimulated in the cold. These responses may be partly mediated by acylated ghrelin immediately after running but other mechanisms are likely involved thereafter. Acute hypoxic exposure suppresses acylated ghrelin concentrations; an observation which may explain the decreased energy intake in hypoxia.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The Acute Effects of Swimming on Appetite, Food Intake, and Plasma Acylated Ghrelin

Swimming may stimulate appetite and food intake but empirical data are lacking. This study examined appetite, food intake, and plasma acylated ghrelin responses to swimming. Fourteen healthy males completed a swimming trial and a control trial in a random order. Sixty min after breakfast participants swam for 60 min and then rested for six hours. Participants rested throughout the control trial. During trials appetite was measured at 30 min intervals and acylated ghrelin was assessed periodically (0, 1, 2, 3, 4, 6, and 7.5 h. N = 10). Appetite was suppressed during exercise before increasing in the hours after. Acylated ghrelin was suppressed during exercise. Swimming did not alter energy or macronutrient intake assessed at buffet meals (total trial energy intake: control 9161 kJ, swimming 9749 kJ). These findings suggest that swimming stimulates appetite but indicate that acylated ghrelin and food intake are resistant to change in the hours afterwards

Acute exercise increases feeding latency in healthy normal weight young males but does not alter energy intake

This study investigated the acute influence of exercise on eating behaviour in an ecologically valid setting whereby healthy active males were permitted complete ad libitum access to food. Ten healthy males completed two, 8 h trials (exercise and control) in a randomised-crossover design. In the exercise trials participants consumed a breakfast snack and then rested for 1 h before undertaking a 60 min run (72% of V˙O2 max) on a treadmill. Participants then rested in the laboratory for 6 h during which time they were permitted complete ad libitum access to a buffet meal. The timing of meals, energy/macronutrient intake and eating frequency were assessed. Identical procedures were completed in the control trial except no exercise was performed. Exercise increased the length of time (35 min) before participants voluntarily requested to eat afterwards. Despite this, energy intake at the first meal consumed, or at subsequent eating episodes, was not influenced by exercise (total trial energy intake: control 7426 kJ, exercise 7418 kJ). Neither was there any difference in macronutrient intake or meal frequency between trials. These results confirm that food intake remains unaffected by exercise in the immediate hours after but suggest that exercise may invoke a delay before food is desired

Intermediate Range Order in Metal-Ammonia Solutions: Pure and Na-Doped Ca-NH_{3}

The local and intermediate range ordering in Ca–NH3 solutions in their metallic phase is determined through H/D isotopically differenced neutron diffraction in combination with empirical potential structure refinements. For both low and high relative Ca concentrations, the Ca ions are found to be octahedrally coordinated by the NH3 solvent, and these hexammine units are spatially correlated out to lengthscales of ∼7.4–10.3 Å depending on the concentration, leading to pronounced ordering in the bulk liquid. We further demonstrate that this liquid order can be progressively disrupted by the substitution of Ca for Na, whereby a distortion of the average ion primary solvation occurs and the intermediate range ion–ion correlations are disrupted

Influence of prolonged treadmill running on appetite, energy intake and circulating concentrations of acylated ghrelin

The effects of prolonged treadmill running on appetite, energy intake and acylated ghrelin (an appetite stimulating hormone) were examined in 9 healthy males over the course of 24 h. Participants completed 2 experimental trials (exercise and control) in a randomised - crossover fashion. In the exercise trial participants ran for 90 min at 68.8 ± 0.8% of maximum oxygen uptake followed by 8.5 h of rest. Participants returned to the laboratory on the following morning to provide a fasting blood sample and ratings of appetite (24 h measurement). No exercise was performed on the control trial. Appetite was measured within the laboratory using visual analogue scales and energy intake was assessed from ad libitum buffet meals. Acylated ghrelin was determined from plasma using an ELISA assay. Exercise transiently suppressed appetite and acylated ghrelin but each remained no different from control values in the hours afterwards. Furthermore, despite participants expending 5324 kJ during exercise there was no compensatory increase in energy intake (24 h energy intake; control 17191 kJ, exercise 17606 kJ). These findings suggest that large energy deficits induced by exercise do not lead to acute compensatory responses in appetite, energy intake or acylated ghrelin