Combined Effects Of Foods Research Articles

Drosophila Free-Flight Odor Tracking is Altered in a Sex-Specific Manner By Preimaginal Sensory Exposure.

In insects such as Drosophila melanogaster, flight guidance is based on converging sensory information provided by several modalities, including chemoperception. Drosophila flies are particularly attracted by complex odors constituting volatile molecules from yeast, pheromones and microbe-metabolized food. Based on a recent study revealing that adult male courtship behavior can be affected by early preimaginal exposure to maternally transmitted egg factors, we wondered whether a similar exposure could affect free-flight odor tracking in flies of both sexes. Our main experiment consisted of testing flies differently conditioned during preimaginal development in a wind tunnel. Each fly was presented with a dual choice of food labeled by groups of each sex of D. melanogaster or D. simulans flies. The combined effect of food with the cis-vaccenyl acetate pheromone (cVA), which is involved in aggregation behavior, was also measured. Moreover, we used the headspace method to determine the "odorant" identity of the different labeled foods tested. We also measured the antennal electrophysiological response to cVA in females and males resulting from the different preimaginal conditioning procedures. Our data indicate that flies differentially modulated their flight response (take off, flight duration, food landing and preference) according to sex, conditioning and food choice. Our headspace analysis revealed that many food-derived volatile molecules diverged between sexes and species. Antennal responses to cVA showed clear sex-specific variation for conditioned flies but not for control flies. In summary, our study indicates that preimaginal conditioning can affect Drosophila free flight behavior in a sex-specific manner.

Using Wave and Energy Theories on Quantitative Control of Postprandial Plasma Glucose via Optimized Combination of Food and Exercise (Math-Physical Medicine)

The author used math-physical medicine to research and identify the quantitative relationship between postprandial plasma glucose (PPG) and the combined effect of food and exercise. Applying both wave theory and energy theory from physics on his big data analytics, he can further observe and analyze the PPG waveforms in detail. And then, he was able to derive certain practical rules to guide how to control PPG via fine-tuning the combination of food and exercise.

Combined effects of food and exercise on anaphylaxis

Food-dependent exercise-induced anaphylaxis (FDEIAn) is induced by different types and various intensities of physical activity, and is distinct from food allergies. It has been shown that consumption of allergenic food followed by exercise causes FDEIAn symptoms. Intake of allergenic food or medication before exercise is a major predisposing factor for FDEIAn. Urticaria and severe allergic reactions are general symptoms of FDEIAn. Dermatological tests and serum IgE assays are the typical prescreening methods, and have been used for several decades. However, these screening tests are not sufficient for detecting or preventing FDEIAn. It has been found that exercise may stimulate the release of mediators from IgE-dependent mast cells that can result in FDEIAn when a certain threshold level has been exceeded. Mast cell degradation might be a major factor to induce FDEIAn but this has not been determined. A number of foods have been reported to be involved in the onset of FDEIAn including wheat, eggs, chicken, shrimp, shellfish, nuts, fruits, and vegetables. It is also known that aspirin increases the occurrence of type I allergy symptoms when combined with specific foods. Moreover, high intensity and frequent exercise are more likely to provoke an attack than low intensity and less frequent exercise. In this paper, we present the current views of the pathophysiological mechanisms underlying FDEIAn within the context of exercise immunology. We also present a detailed FDEIAn definition along with etiologic factors and medical treatment for cholinergic urticaria (UC) and exercise-induced anaphylaxis (EIA).

Effects of prenatal food and micronutrient supplementation on child growth from birth to 54 months of age: a randomized trial in Bangladesh

BackgroundThere is a lack of information on the optimal timing of food supplementation to malnourished pregnant women and possible combined effects of food and multiple micronutrient supplementations (MMS) on their offspring's growth. We evaluated the effects of prenatal food and micronutrient interventions on postnatal child growth. The hypothesis was that prenatal MMS and early invitation to food supplementation would increase physical growth in the offspring during 0-54 months and a combination of these interventions would further improve these outcomes.MethodsIn the large, randomized MINIMat trial (Maternal and Infant Nutrition Interventions in Matlab), Bangladesh, 4436 pregnant women were enrolled between November 2001 and October 2003 and their children were followed until March 2009. Participants were randomized into six groups comprising 30 mg Fe and 400 μg folic acid (Fe30F), 60 mg Fe and 400 μg folic acid (Fe60F) or MMS combined with either an early (immediately after identification of pregnancy) or a later usual (at the time of their choosing, i.e., usual care in this community) program invitation to food supplementation. The anthropometry of 3267 children was followed from birth to 54 months, and 2735 children were available for analysis at 54 months.ResultsThere were no differences in characteristics of mothers and households among the different intervention groups. The average birth weight was 2694 g and birth length was 47.7 cm, with no difference among intervention groups. Early invitation to food supplementation (in comparison with usual invitation) reduced the proportion of stunting from early infancy up to 54 months for boys (p = 0.01), but not for girls (p = 0.31). MMS resulted in more stunting than standard Fe60F (p = 0.02). There was no interaction between the food and micronutrient supplementation on the growth outcome.ConclusionsEarly food supplementation in pregnancy reduced the occurrence of stunting during 0-54 months in boys, but not in girls, and prenatal MMS increased the proportion of stunting in boys. These effects on postnatal growth suggest programming effects in early fetal life.Trial registration numberISRCTN: ISRCTN16581394

Ecologically relevant measures of tolerance to potentially lethal temperatures

The acute thermal tolerance of ectotherms has been measured in a variety of ways; these include assays where organisms are shifted abruptly to stressful temperatures and assays where organisms experience temperatures that are ramped more slowly to stressful levels. Ramping assays are thought to be more relevant to natural conditions where sudden abrupt shifts are unlikely to occur often, but it has been argued that thermal limits established under ramping conditions are underestimates of true thermal limits because stresses due to starvation and/or desiccation can arise under ramping. These confounding effects might also impact the variance and heritability of thermal tolerance. We argue here that ramping assays are useful in capturing aspects of ecological relevance even though there is potential for confounding effects of other stresses that can also influence thermal limits in nature. Moreover, we show that the levels of desiccation and starvation experienced by ectotherms in ramping assays will often be minor unless the assays involve small animals and last for many hours. Empirical data illustrate that the combined effects of food and humidity on thermal limits under ramping and sudden shifts to stressful conditions are unpredictable; in Drosophila melanogaster the presence of food decreased rather than increased thermal limits, whereas in Ceratitis capitata they had little impact. The literature provides examples where thermal limits are increased under ramping presumably because of the potential for physiological changes leading to acclimation. It is unclear whether heritabilities and population differentiation will necessarily be lower under ramping because of confounding effects. Although it is important to clearly define experimental methods, particularly when undertaking comparative assessments, and to understand potential confounding effects, thermotolerance assays based on ramping remain an important tool for understanding and predicting species responses to environmental change. An important area for further development is to identify the impact of rates of temperature change under field and laboratory conditions.

Individual and combined effects of foods on helicobacter pylori growth

Eradication of H. pylori can reduce the risk of non-cardia gastric cancer developing in infected humans. Thus, the consumption of foods that inhibit the growth of these bacteria may provide an alternative to current therapies that include antibiotics, proton pump inhibitors and/or bismuth salts. This study describes a simple broth dilution assay developed to screen a range of foods for their individual and combined effects on H. pylori growth. It was found that foods with measurable anti-H. pylori activity have an effect greater in combination than the sum of foods tested singly, and that this was most noticeable with a combination of broccoli sprouts and blackcurrant oil. The results suggest that food synergy should be considered in any nutraceutical approach to H. pylori infection.

Combined food and predator effects on songbird nest survival and annual reproductive success: results from a bi-factorial experiment

Food and predators have traditionally been viewed as mutually exclusive alternatives when considering factors affecting animal populations. This has led to long controversies such as whether annual reproductive success in songbirds is primarily a function of food-restricted production or predator-induced loss. Recent studies on both birds and mammals suggest many of these controversies may be resolved by considering the combined effects of food and predators. We conducted a 2x2 manipulative food addition plus natural predator reduction experiment on song sparrows (Melospiza melodia) over three consecutive breeding seasons. Food and predators together affected partial clutch or brood loss, nest survival (total clutch or brood loss) and annual reproductive success. When combined, our two treatments reduced partial losses by more than expected if the effects of food and predators were independent and additive. Food and predators also interacted in their effects on nest survival since food addition significantly reduced the rate of nest predation. While annual reproductive success was highly correlated with nest predation (r2=0.71) the strength of this relationship was reinforced by the indirect effects of food addition on nest predation. A stepwise multiple regression showed that the residual variation in annual reproductive success was explained by food effects on the total number of eggs laid over the season and the combined effects of food and predators on partial losses noted above. We conclude that annual reproductive success in song sparrows is a function of both food-restricted production and predator-induced loss and indirect food and predator effects on both clutch and brood loss. We highlight the parallels between our results and those from a comparable bi-factorial experiment on mammals because we suspect combined food and predator effects are likely the norm in both birds and mammals.

Combined effects of food level and inoculation density on competition between Brachionus patulus (Rotifera) and the cladocerans Ceriodaphnia dubia and Moina macrocopa

Competition among cladocerans and rotifers is of considerable interest not only due to their close similarity in life history strategies, but also due to the considerable overlap they exhibit in their feeding habits. In tropical waterbodies, several genera of cladocerans, including Ceriodaphnia and Moina occur, simultaneously with rotifers. We tested over a period of 3 weeks the combined effects of food (0.5×106 and 1.5×106 cells ml−1 of Chlorella) level and rotifer density on the competition between B. patulus and C. dubia and M. macrocopa using population growth experiments. For each cladoceran species we used 30 test jars of 50 ml capacity. The initial density of cladocerans was 0.2 ind ml−1, while for B. patulus it was either 1 ind ml−1 or 5 ind ml−1. Neither the maximal population density nor the rate of population increase (r) of C. dubia was significantly affected by B. patulus. However, for M. macrocopa, both these variables were negatively affected by the rotifers. The combined effects of low food level and high initial density of B. patulus resulted in a 50% reduction in the peak population density of M. macrocopa. The population growth of B. patulus was negatively influenced by the presence of C. dubia and M. macrocopa. The results of the competition experiments conducted in the present study between cladocerans and rotifers suggest the existence of a more complex and delicate interaction than is generally thought.

Comparisons of Laboratory Bioassays and a Whole‐Lake Experiment: Rotifer Responses to Experimental Acidification

We test whether data from laboratory bioassays can be used to predict zooplankton responses during a whole—lake experiment using two rotifers, Keratella cochlearis and Keratella taurocephala. The acidification experiment was conducted in Little Rock Lake, Wisconsin, USA, which was divided into a reference basin maintained at a natural pH near 6.1 and a treatment basin which was acidified in 2—yr stages to pH values of 5.6, 5.2, and 4.7. Laboratory assays examined the effect of pH on reproduction under varied food conditions and survivorship without food. In the lake, the two rotifers showed strong and opposite responses to acidification: K. cochlearis decreased in abundance while K. taurocephala increased. In the laboratory bioassays, neither species was sensitive to pH when food conditions yielded high reproductive rates. When food was limited, K. cochlearis exhibited lower survivorship and a trend towards lower reproductive rates at lower pH. With limited food, K. taurocephala survivorship was either unaffected by pH or higher at high pH and its reproduction was slightly higher at intermediate pH. In situ experiments revealed that food conditions in the treatment basin lowered reproduction by K. cochlearis, indicating that a combined effect of food and pH caused its population decline. Neither food nor pH could explain the increase in K. taurocephala, which appeared to be linked to a reduction in its predators at lower pH. Overall, our analyses revealed substantial discrepancies between laboratory bioassays and in—lake responses. This was particularly the case for K. taurocephala, for which assays predicted no changes or a decline in abundance rather than the marked increase that actually occurred. Our results suggest that caution should be used in extending results from laboratory assays to natural ecosystems.

Reproductive performance of the African migratory locust,Locusta migratoria migratorioides(Orthoptera: Acrididae), in a cereal crop environment in South Africa

AbstractThe reproductive performance of the African migratory locust,Locusta migratoria migratorioides(Reiche & Fairmaire), was assessed in a cereal crop environment on the temperate Highveld of South Africa. Of the two principal crops involved on the Highveld, maize realized the highest reproductive potential during summer, wheat was successfully utilized for breeding in spring. The combined effects of food and temperature were the main factors influencing seasonal variation in clutch size. Green food was essential for continued reproduction, oviposition ceased for three to four months during winter when food resources deteriorated and was resumed in spring. Although locust size was shown to decrease significantly in early winter, this did not influence fecundity. The effects of egg resorption, female age and phase on clutch size are outlined. Despite the more adverse climate of the Highveld, the migratory locust realized higher individual natality in the cereal crop environment than that recorded previously and consequently achieved outstanding reproductive success in this alternative habitat.

Population dynamics ofBrachionus patulus Muller (Rotifera) in relation to food and temperature

The combined effects of food (Chlorella) and temperature on the population growth of a laboratory clone of the rotiferBrachionus patulus were studied. The intrinsic rate of increase (r) as well as the maximum densities achieved were a function of temperature. While ther was negative at 15°C regardless of food level, its magnitude was dependent on food level at medium (25°C) and high (35°C) temperatures, indicating a significant temperature × food interaction. The seasonal variations in the abundance ofBrachionus patulus in the plankton of a regularly sampled pond are explained in terms of the observed food-temperature effects on the survival and reproduction of the laboratory population.

The effect of food and exercise on the skin response to compound [formula omitted] in patients with food-associated exercise-induced urticaria-angioedema

Food-associated, exercise-induced urticaria-angioedema is increasingly being recognized. We studied five atopic individuals in whom ingestion of food was followed by exercise-induced urticaria-angioedema. The combined effect of food and exercise on skin wheal response to compound 48 80 and histamine was studied. Symptoms could be reproduced in only four of the patients who performed strenuous exercise after ingestion of food to which they were skin sensitive. When symptoms appeared, that is, after a combination of food and exercise challenge, there was a marked increase in the wheal response to compound 48 80 (>200%) and not to histamine. Food or exercise challenge alone did not induce any significant change in the skin reactivity to compound 48 80 or to histamine. It was concluded that mast cell releasability could be increased when the patient was subjected to combined factors.