HPLC/FLD를 이용한 성별·연령별 혈장 homocysteine 정상치 조사

이경옥,류광석,이규범,이경옥,류광석,이규범 대한임상검사정도관리학회 1999 臨床檢査와 精度管理 Vol.21 No.1

How Caterpillars Overcome the Early Life Experience of Nutritional Imbalance: The Role of Developmental Plasticity and Dietary Compensation

Kwang Pum Lee,Soon-Tak Kwon,Chris Seung-Don Roh,Myung Suk Rho,Taehwan Jang 한국응용곤충학회 2014 한국응용곤충학회 학술대회논문집 Vol.2014 No.04

Nutritional conditions experienced during early growth have important implications for the lifetime fitness of herbivores. We investigated how the early life effects of imbalanced nutrient intake can be overcome in a generalist caterpillar, Spodoptera litura (Lepidoptera: Noctuidae). Over the fifth larval instar, caterpillars were pretreated on one of three diets that varied in protein: carbohydrate balance (p35:c7, p21:c21 or p7:c35). After molting to the sixth instar, they were transferred to one of three no-choice diets (p35:c7 ,p21:c21 or p7:c35) or a food choice where they received two nutritionally complementary diets (p35:c7 versus p7:c35). Approximately 80% of caterpillars that had been protein-deprived (p7:c35) during the fifth instar molted to the seventh instar. The threshold body mass for pupal metamorphosis was 144 mg at the start of the sixth instar. When given a choice, caterpillars pretreated on the low-protein diet (p7:c35) selected significantly more protein than those from other diets (p35:c7,p21:c21). Our results suggest that caterpillars are not only capable of switching their developmental program to reduce the deleterious effects of a nearly deficiency of protein, but also flexible at adjusting nutrient preference store dress specific nutritional imbalances experienced early in life.

Temperature-by-nutrient interactions affecting growth rate in an insect ectotherm

Lee, Kwang Pum,Roh, Chris Blackwell Publishing Ltd 2010 Entomologia experimentalis et applicata Vol.136 No.2

<P>Abstract</P><P>Temperature and nutrition are two prominent environmental variables influencing juvenile growth rate in ectotherms. These two factors interact in complex ways. Here, we present a comprehensive analysis of the interactive effects of temperature and nutrition on various components of fitness (growth rate, survival), food intake, and level of energy storage in an insect herbivore, caterpillars of <I>Spodoptera exigua</I> Hübner (Lepidoptera: Noctuidae). In a factorial experimental design, final-instar caterpillars (i.e., fifth instars) were individually reared at one of three constant temperatures (18, 26, and 34 °C), in which they received one of six diets differing in their ratio of protein and digestible carbohydrate [P:C mixture, expressed as the percentage of diet by dry mass: protein 42%:carbohydrate 0% (42:0), 35:7, 28:14, 21:21, 14:28, and 7:35]. Within the range of test temperatures, larval growth rate increased with rising temperature and was strongly affected by P:C mixture, reaching a maximum on moderate P:C diets at each temperature and falling at very high and low P:C mixtures. There was a significant temperature*diet interaction, such that the difference in growth rates between temperatures was greatest on moderate P:C diets and least on the most extreme diets (42:0 and 7:35). Food intake rate patterns followed a similar trend to growth rate. Rapidly growing animals at high ambient temperature suffered high mortality across all dietary P:C mixtures, but to a greater extent on the extremely unbalanced diets. This suggests that there are developmental and physiological costs associated with fast growth at high temperature, as indicated by high rate of pupation failure and reduced lipid storage efficiency. Our study shows how temperature and nutrition interplay to mediate phenotypic variations in growth rates and energy utilization in an insect ectotherm.</P>

Temperature-size rule is modulated by macronutrient balance in a caterpillar

Kwang Pum Lee,Taehwan Jang,Myung Suk Rho 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.04

Most ectotherms mature at a larger body size in colder conditions. This negative relationship between developmental temperature and final body size is termed the temperature-size rule. In this study, we investigated how dietary protein:carbohydrate (P:C) balance modulates the fundamental relationship between temperature and body size in the final-instar caterpillars of Spodoptera litura. The magnitude and sign of the thermal reaction norm for body size were altered by the dietary P:C balance of the food eaten by caterpillars. The slope of the reaction norm was flat for caterpillars raised on a nutritionally balanced food (P:C = 1:1) but was negative for those on imbalanced foods (1:5 or 5:1). When allowed to self-compose their preferred diet, caterpillars preferred carbohydrate-rich food at higher temperatures. The negative impact of high temperature on body size was mitigated by such a temperature-driven shift in nutrient preference. This study highlights the importance of macronutrient balance as a key factor modulating the relationship between temperature and body size in insects.

The effects of ambient temperature on food selection, nutrient utilization, and performance in a generalist caterpillar, Spodoptera litura

Nergui Ravzanaadii,Kwang Pum Lee 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

Temperature and nutrition are the two most important environmental factors influencing growth and survival in immature insects. There is ample evidence of interactions between these two factors but still little is known how changes in thermal environment affect feeding and nutrient utilization insect ectotherms. The aim of this study is to investigate the potential effects of ambient temperature on food selection and post-ingestive nutritional physiology in a generalist-feeding caterpillar of Spodorptera litura. Two separate experiments were performed. The first was a food choice experiment in which caterpillars were maintained through their final larval stadium under one of three constant temperatures(20,25,30°) and given a choice between two nutritionally unbalanced diets that differed in protein(p) and carbohydrate(c) content (p42:c0 vs p7:c35 and p35:c7 vs p7:c35). In the second experiment, caterpillars were kept at the same thermal conditions as the first experiment but received a single diet from three no-choice feeding treatments(p35:c7,p21:c21and p7:c35). When raised at the highest temperature (30C), caterpillars from the choice experiment selected significantly more carbohydrate than those on lower temperatures whereas protein intake did not differ significantly between caterpillars across three test temperatures. Results from the no-choice experiment showed that lipid storage efficiency was reduced when caterpillars were maintained at the highest temperature(30C). In both experiments, growth rate increased progressively with rising temperature. However, there was a significant temperature-by-diet interaction, with growth rates increasing more rapidly on p21:c21 diet than on the other diets(p35:c7 and p7:c35). Our results demonstrate that caterpillars adjust their nutrient preference to meet the increased energetic demand at high ambient temperature.

The Effects of Mating on Starvation Resistance in Drosophila melanogaster

Taehwan Jang,Kwang Pum Lee 한국응용곤충학회 2014 한국응용곤충학회 학술대회논문집 Vol.2014 No.10

Mating elicits a dramatic changes in physiology, behavior, and life-history traits in insects, but little is known about the relationship between mating and the capacity of insects to resist environmental stressors. Starvation is one of the most ubiquitous forms of environmental stress faced by all insects under natural conditions. Previous studies using Drosophila melanogaster flies has shown that mated females lived longer under starvation than did virgin females, but the mechanistic basis for such post-mating increase in starvation resistance remains largely unexplored. The objective of this study was to investigate the behavioral and physiological mechanisms of mating-induced alteration in starvation resistance and its heritable genetic variations in D. melanogaster. In the first experiment (Experiment 1), we compared starvation resistance (measured as starving time before death), body compositions, and food intake between mated and unmated flies of both sexes using a large outbred population. In the second experiment (Experiment 2), starvation resistance and body composition were quantified for mated male and female flies derived from each of 19 highly inbred genetic lines. Results from Experiment 1 showed that mated females were better able to resist starvation than virgin females and males because they ate more and thus laid down more fats in their body. Results from Experiment 2 revealed a significant heritable genetic variation in starvation resistance and its correlated body composition parameters for both sexes. Overall, females had a higher starvation resistance than males, but the magnitude of such intersexual difference varied among genetic lines, as suggested by a significant sex-by-line interaction. Cross-sex genetic correlations were highly significant and positive for starvation resistance, indicating that the genetic factors controlling the starvation resistance in D. melanogaster are shared between the two sexes.

Genotype by Nutrient Interactions for Starvation Resistance in Drosophila melanogaster

Taehwan Jang,Kwang Pum Lee 한국응용곤충학회 2014 한국응용곤충학회 학술대회논문집 Vol.2014 No.04

Starvation resistance is an important fitness trait that is controlled by both environmental and heritable factors. The main objective of this study is to explore the genotype-by-nutrient interactions for starvation resistance and its correlating physiological traits in Drosophila melanogaster. In this study, we conducted a split-family quantitative genetic experiment, in which female adults of Drosophila from 19 isofemale genetic lines were allowed to ingest one of two synthetic diets that differed in protein-to-carbohydrate ratio (P:C = 4:1 or 1:16 with the P+C concentration of 120 g L-1) before they were assayed for starvation time and lipid storage. In all genetic lines, Drosophila flies that had fed carbohydrate-rich diet (P:C=1:16) resisted starvation better and stored more lipids than did those that had fed protein-rich diet (4:1). Importantly, the extent to which both starvation resistance and lipid reserves were affected by dietary P:C ratio varied greatly among different genetic lines of Drosophila, as indicated by significant genotypeby-nutrient interactions for these two traits. When the patterns of the bivariate reaction norm for body lipid and starvation resistance were compared across the genotypes, we found strong evidence for genetic variations in the pattern of energy storage and usage associated with maintaining survival under starvation in Drosophila.

Fitness consequences of nutrient balancing in a caterpillar

Cheon-Ok Lee,Kwang Pum Lee 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.10

Foraging is fundamental to animal survival and reproduction, and animals often require more than one nutrient to maximize their evolutionary fitness. Here, we test whether caterpillars of Spodoptera exigua (Hübner) balance the intake of multiple nutrients to meet their nutrient requirement. In the choice test, final-instar larvae were offered a choice of two nutritionally complementary diets [1) p42:c0 vs. p0:c42, 2) p42:c0 vs. p7:c35, 3) p35:c7 vs. p0:c42, 4) p35:c7 vs. p7:c35, 5) p35:c7 vs. p5.6:c28, 6) p28:c5.6 vs. p7:c35 and 7) p28:c5.6 vs. p5.6:c28]. Caterpillars tightly regulated their intake of protein (P) and carbohydrate (C) to defend a specific nutrient composition, which was slightly carbohydrate-biased (P:C=1:1.2). In the no-choice test, larvae were restricted to feed on one of 42 diets that varied both in P:C mixtures (1:0, 5:1, 2:1, 1:1, 1:2 and 1:5) and in total nutrient concentration(P+C=67.2%, 58.8%, 50.4%, 42%, 33.6%, 25.2% and 16.8%). Fitness landscapes fitted for key larval fitness variables (e.g., growth rate) over these range of diets revealed that the larval performance was optimized at the regulated position of nutrient intake in this caterpillar.

Quantitative genetic analysis of sex differences in starvation resistance: a case of Drosophila melanogaster

Taehwan Jang,Kwang Pum Lee 한국응용곤충학회 2015 한국응용곤충학회 학술대회논문집 Vol.2015 No.10

Recent studies have shown that mating can alter starvation resistance in female D. melanogaster, but little is known about the behavioral and physiological mechanisms underlying such mating-mediated changes in starvation resistance. In the present study, we first investigated whether the effect of mating on starvation resistance is sex-specific in D. melanogaster. As indicated by a significant sex × mating status interaction, mating increased starvation resistance in females but not in males. In female D. melanogaster, post-mating increase in starvation resistance was mainly attributed to increases in food intake and in the level of lipid storage relative to lean body weight. We then performed quantitative genetic analysis to estimate the proportion of the total phenotypic variance attributable to genetic differences (i.e., heritability) for starvation resistance in mated male and female D. melanogaster. The narrow-sense heritability (h2) of starvation resistance was 0.235 and 0.155 for males and females, respectively. Mated females were generally more resistant to starvation than males, but the degree of such sexual dimorphism varied substantially among genotypes, as indicated by a significant sex × genotype interaction for starvation resistance. Cross-sex genetic correlation was greater than 0 but less than l for starvation resistance, implying that the genetic architecture of this trait was partially shared between the two sexes. For both sexes, starvation resistance was positively correlated with longevity and lipid storage at genetic level. The present study suggests that sex differences in starvation resistance depend on mating status and have a genetic basis in D. melanogaster.

Nutrient regulation by a generalist caterpillar of Spodoptera exigua

Cheon-Ok Lee,Kwang Pum Lee 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.05

The aim of this research was to demonstrate whether generalist-feeding caterpillars of Spodoptera exigua (Hübner) regulate their nutrient intake when faced with nutritionally variable food conditions. Six, chemically-defined diets were prepared that differed in the composition of protein and digestible carbohyrate:42% protein with 0% carbohydrate by dry mass(p42:c0), p35:c7, p28:c5.6, p7:c35, p5.6:c28 and p0:42. A total of 288 newly-ecdysed final instar(5th) caterpillars were collected and assigned randomly into 7 food pairing treatments, in which they were allowed to choose between two diet block:one with high P:C ratio and the other with low ratio [1) p42:c0 vs. p0:c42, 2) p42:c0 vs. p7:c35, 3) p35:c7 vs. p0:c42, 4) p35:c7 vs. p7:c35, 5) p35:c7 vs. p5.6:c28, 6) p28:c5.6 vs. p7:c35 and 7) p28:c5.6 vs. p5.6:c28]. Various aspects of food intake and larval performance variables were measured for each insect, including larval survival, stadium duration, pupal mass and body lipid composition. Results showed that the intake of protein and carbohydrate self-composed by caterpillars in all treatments converged to a point in a bivariate nutrient plot and the ratio of protein to carbohydrate averaged over these converging intake points was close to 1:1. This indicates that S. exigua caterpillars have capacity to balance their nutrient intake by defending their species-specific ‘intake target’ despite the differences in amount and proportion of nutrients available in each food choice treatment.