Family history of alcoholism and the human brain response to oral sucrose

A heightened hedonic response to sweet tastes has been associated with increased alcohol preference and alcohol consumption in both humans and animals. The principal goal of this study was to examine blood oxygenation level dependent (BOLD) activation to high- and low-concentration sweet solutions in subjects who are either positive (FHP) or negative (FHN) for a family history of alcoholism. Seventy-four non-treatment seeking, community-recruited, healthy volunteers (22.8 ± 1.6 SD years; 43% men) rated a range of sucrose concentrations in a taste test and underwent functional magnetic resonance imaging (fMRI) during oral delivery of water, 0.83 M, and 0.10 M sucrose. Sucrose compared to water produced robust activation in primary gustatory cortex, ventral insula, amygdala, and ventral striatum. FHP subjects displayed greater bilateral amygdala activation than FHN subjects in the low sucrose concentration (0.10 M). In secondary analyses, the right amygdala response to the 0.10 M sucrose was greatest in FHP women. When accounting for group differences in drinks per week, the family history groups remained significantly different in their right amygdala response to 0.10 M sucrose. Our findings suggest that the brain response to oral sucrose differs with a family history of alcoholism, and that this response to a mildly reinforcing primary reward might be an endophenotypic marker of alcoholism risk

Ghrelin is not Related to Hunger or Calories Consumed at Breakfast in Lean and Obese Women

poster abstractBackground: The mechanisms that result in greater caloric intake in obese individuals are incompletely understood. Ghrelin administration increases ad lib food intake in humans. We investigated the relationship of ghrelin to calorie consumption and hunger at breakfast on two separate occasions in lean and obese women. Methods: 23 lean (BMI 22.3±0.5 kg/m2, 26.5±1.0 yr) and 25 obese (BMI 36.9±0.7 kg/m2, 27.8±1.1 yr) women participated in a noncontiguous 2 day study. The minimum and maximum days between visits were 6 and 43 days. Participants were given the same breakfast on both days (turkey sausage, French toast with margarine/syrup, fruit cup, coffee, tea, diet soda, or water) with portions adjusted to provide 20% of the daily energy requirement for weight maintenance. Subjects were instructed to eat until full. Hunger was evaluated on a Satiety Labeled Intensity Magnitude Scale (SLIM) before and after the meal. Anchors were “greatest imaginable fullness” at 0 and “greatest imaginable hunger” at 100. Blood samples were collected over 120 minutes for measurement of active ghrelin. Results: Lean subjects consumed an equivalent number of calories on both days (380.0±14.6 vs 378.2±14.9 kcal), as did the obese (419.4±16.2 vs 428.8±15.4 kcal). On average for both days, obese consumed significantly more breakfast calories than lean (424.1±11.1 vs 379.1±10.3 kcal; P<0.01), but the same percentage of calories provided (85.7±1.8 vs 86.1±1.7 %kcal). Lean subjects rated hunger before breakfast the same on both days (69.2±1.6 vs 71.7±1.4), as did the obese (69.8±1.6 vs 69.6±1.8), and there was no difference between the groups. Lean subjects rated hunger after breakfast the same on both days (27.8±1.9 vs 30.3±2.4), as did the obese (25.0±1.7 vs 24.3±1.8). The reduction in hunger score following breakfast was significant for both groups (P<0.0001), with the obese reporting significantly less hunger/more fullness after breakfast than the lean (P=0.02). Fasting ghrelin was significantly greater in the lean than obese women (549.9±58.9 vs 231.0±29.1 pg/ml; P<0.0001). Ghrelin was significantly reduced at 60 min following breakfast in the lean (375.8±49.2 pg/ml; P=0.028) but not the obese (212.2±26.4 pg/ml). Ghrelin was not related to hunger score prior to breakfast, and there was no relationship between reduction in ghrelin and hunger score in the lean or obese. Conclusion: Caloric intake (as a percentage provided) and hunger scores before breakfast on two occasions were the same for both lean and obese women. Fasting ghrelin was significantly different between lean and obese women but did not predict hunger score or calories consumed. Our findings do not support a role for ghrelin in driving food intake at breakfast

Rhizogenesis and root growth of Carica papaya L.in vitro in relation to auxin sensitive phases and use of riboflavin

High rooting percentages and high-quality adventitious root systems for papaya (Carica papaya L.) were obtained in vitro by appropriate auxin source, duration of exposure to auxin and use of riboflavin. Root initiation of papaya shoots was higher using IBA than IAA, NAA or PCPA. Maximum rooting percentage (96%) was achieved by exposure of shoots to a medium containing 10 μM IBA for 3 days before transfer to a hormone-free medium. However, the resultant plants had small shoots and callused roots. Shoot and root growth were improved when shoots were transferred after 2 days from medium containing 10 μM IBA to hormone-free medium containing 10 μM riboflavin. Good root initiation, and root and shoot growth were also obtained when shoots were incubated for 2 days in darkness on a medium containing 10 μM IBA and 31 μM riboflavin before transfer to light. Alternatively, cultures could be placed in the light on medium containing 10 μM IBA, and after 1 day the medium overlaid with 300 μM riboflavin (1 ml over 10 ml of medium)

Effect of fructose on growth of papaw shoot explants in vitro

The effects on papaw (Carica papaya L.) shoot growth of the carbohydrates sucrose, fructose, glucose and ribose singly and combined, were compared at a range of concentrations, in both autoclaved and filtered media. Fructose (10 g L-1), when autoclaved together with other media components, consistently promoted growth of shoots from buds on nodal sections or buds excised with a wedge of stem tissue. This enhancement was seen if the fructose was used singly or in combination with 10 g L-1 sucrose. By contrast, autoclaved media containing fructose reduced growth of small axillary bud explants. Decreasing the pH of fructose solution from 5.8 to 4.4 before autoclaving enhanced growth of buds from nodal sections. Other sugars in the D-ketose group inhibited papaw shoot growth totally when autoclaved with other media components. A radish cotyledon bioassay of solutions of fructose autoclaved singly or with NH4NO3 (20 mM) showed no evidence of cytokinin effects

Lineages, lineage stability and pattern formation in leaves of variegated chimeras of Lophostemon confertus (R. Br.) Wilson & Waterhouse and Tristaniopis laurina (Smith) Wilson & Waterhouse (Myrtaceae)

Three variegated chimeras of L. confertus and T. laurina arise spontaneously in seedling populations: 1, white margin: green centre, 2, green margin: light green centre and 3, green margin: white centre. Types 1 and 2 are found in T. laurina and types 1 and 3 in L. confertus. We have determined chloroplast distribution in the leaf tissues by fluorescence microscopy to assess the basis for these colour patterns. In L. confertus, a layer of collenchyma underlies the adaxial epidermis, replaces the upper layer of palisade, and does not mask mutant inner tissues, concealed by the adaxial layer of palisade in type 2 leaves of T. laurina. The central colour patterns are explained on the basis of accepted paths of cell lineage in leaf development (protoderm green in all three types; hypodermal derivatives genetically green in 2 and 3; and subhypodermal cells chlorophyll-deficient in types 2 and 3). The cell lineages postulated are similar in both species and we show that the observations can be accounted for only by a shift in lineage path during leaf ontogeny. We conclude that some established concepts of leaf ontogeny require revision

Germination of Verticordia pollen after storage at different temperatures

Longevity of Verticordia pollen was assessed to develop the technology necessary to allow hybridisation of species that flower in different seasons. Pollen, either attached to the stigmatic pollen presenter or within the anther, was desiccated and stored at temperatures from ambient to -196°C. Verticordia pollen retained 75-80% viability at -196°C, and even when stored at room temperature for 6 months maintained a viability of 50%

Ventral frontal satiation-mediated responses to food aromas in obese and normal-weight women

BACKGROUND: Sensory properties of foods promote and guide consumption in hunger states, whereas satiation should dampen the sensory activation of ingestive behaviors. Such activation may be disordered in obese individuals. OBJECTIVE: Using functional magnetic resonance imaging (fMRI), we studied regional brain responses to food odor stimulation in the sated state in obese and normal-weight individuals targeting ventral frontal regions known to be involved in coding for stimulus reward value. DESIGN: Forty-eight women (25 normal weight; 23 obese) participated in a 2-day (fed compared with fasting) fMRI study while smelling odors of 2 foods and an inedible, nonfood object. Analyses were conducted to permit an examination of both general and sensory-specific satiation (satiation effects specific to a given food). RESULTS: Normal-weight subjects showed significant blood oxygen level-dependent responses in the ventromedial prefrontal cortex (vmPFC) to food aromas compared with responses induced by the odor of an inedible object. Normal-weight subjects also showed general (but not sensory-specific) satiation effects in both the vmPFC and orbitofrontal cortex. Obese subjects showed no differential response to the aromas of food and the inedible object when fasting. Within- and between-group differences in satiation were driven largely by changes in the response to the odor of the inedible stimulus. Responses to food aromas in the obese correlated with trait negative urgency, the tendency toward negative affect-provoked impulsivity. CONCLUSIONS: Ventral frontal signaling of reward value may be disordered in obesity, with negative urgency heightening responses to food aromas. The observed nature of responses to food and nonfood stimuli suggests that future research should independently quantify each to fully understand brain reward signaling in obesity

Family history of alcoholism and the human brain response to oral sucrose

A heightened hedonic response to sweet tastes has been associated with increased alcohol preference and alcohol consumption in both humans and animals. The principal goal of this study was to examine blood oxygenation level dependent (BOLD) activation to high- and low-concentration sweet solutions in subjects who are either positive (FHP) or negative (FHN) for a family history of alcoholism. Seventy-four non-treatment seeking, community-recruited, healthy volunteers (22.8 ± 1.6 SD years; 43% men) rated a range of sucrose concentrations in a taste test and underwent functional magnetic resonance imaging (fMRI) during oral delivery of water, 0.83 M, and 0.10 M sucrose. Sucrose compared to water produced robust activation in primary gustatory cortex, ventral insula, amygdala, and ventral striatum. FHP subjects displayed greater bilateral amygdala activation than FHN subjects in the low sucrose concentration (0.10 M). In secondary analyses, the right amygdala response to the 0.10 M sucrose was greatest in FHP women. When accounting for group differences in drinks per week, the family history groups remained significantly different in their right amygdala response to 0.10 M sucrose. Our findings suggest that the brain response to oral sucrose differs with a family history of alcoholism, and that this response to a mildly reinforcing primary reward might be an endophenotypic marker of alcoholism risk