• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1805-1811
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• 2007

A simulation study was conducted to evaluate the effect of reciprocal cross on the detection and characterization of parent-of-origin (POE) QTL in $F_2$ QTL populations. Data were simulated under two different mating designs. In the one-way cross design, six $F_0$ grand sires of one breed and 30 $F_0$ grand dams of another breed generated 10 $F_1$ offspring per dam. Sixteen $F_1$ sires and 64 $F_1$ dams were randomly chosen to produce a total of 640 $F_2$ offspring. In the reciprocal design, three $F_0$ grand sires of A breed and 15 $F_0$ grand dams of B breed were mated to generate 10 $F_1$ offspring per dam. Eight $F_1$ sires and 32 $F_1$ dams were randomly chosen to produce 10 $F_2$ offspring per $F_1$ dam, totaling 320 $F_2$ offspring. Another mating set comprised three $F_0$ grand sires of B breed and 15 $F_0$ grand dams of A breed to produce the same number of $F_1$ and $F_2$ offspring. A chromosome of 100 cM was simulated with large, medium or small QTL with fixed or different allele frequencies in parental breeds. A series of tests between Mendelian and POE models were applied to characterize QTL as Mendelian, paternal, maternal or partial expression QTL. The overall detection powers were similar between the two mating designs. However, the proportions of paternally expressed QTL that were declared as paternal QTL type were greater in the reciprocal cross design than in the one-way cross, and vice versa for Mendelian QTL. When QTL alleles were segregating in parental breeds, a significant proportion of Mendelian QTL were spuriously declared POE QTL, suggesting that care must be taken to characterize imprinting QTL in a QTL mapping population with a small number of $F_1$ parents.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1519-1524
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• 2015

It is well known that prepartum sows have an innate motivation to build a nest before parturition. Under commercial conditions, however, the farrowing crate, which is widely used in modern pig husbandry, inhibits this innate behaviour through the lack of space, materials, or both. Thus, restriction of nest-building behaviour could generate increased stress, resulting in a decrease in maternal endogenous hormones. Hence, it could lead to detrimental effects on farrowing and lactating performance. Here we review interactions between prepartum nest-building behaviour, stress and maternal endogenous hormone levels, and discuss their effects on parturition, lactation, and welfare of sows and offspring.

• Korean Journal of Child Studies
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• v.32 no.4
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• pp.83-97
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• 2011

The purpose of this study was to examine the relationship between socioeconomic status, maternal involvement in learning, parenting behavior and children's self-determination motivation. The participants of this study consisted of 333 fifth- and sixth-grade elementary school children and their mothers living in Seoul. The results of this study indicated that mothers with a higher educational attainment reported greater autonomy support behavior and involvement in their offspring's learning. Conversely, mothers with low incomes were found to use psychological control and were also found to be involved in learning to a lesser degree. Hierarchical multiple regression analysis indicated that children whose mothers were less involved in learning showed higher levels of self-determination motivation. Additionally, maternal support for autonomy and psychological control had a number of moderating effects on the association between maternal involvement in learning and the child's self-determination motivation. Specifically, children tended to exhibit significantly lower levels of self-determination motivation when mothers were more involved in learning among those who received less support in terms of autonomy. Conversely, children had significantly higher levels of self-determination motivation when mothers were less involved in learning when it came to those children who were under less psychological control.

• Journal of Life Science
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• v.33 no.6
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• pp.455-462
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• 2023

During pregnancy, maternal immune activation (MIA) from infection increases the risk of neurodevelopmental diseases, including schizophrenia and autism spectrum disorders. MIA induced by polyinosinic-polycytidylic acid (poly (I:C)) and lipopolysaccharide (LPS) in animal experiments has led to offspring with abnormal behaviors and brain development. In addition, it has recently been reported that microglia, which reside in the brain and function as immune cells, play an important role in behavioral abnormalities and brain development in MIA-induced offspring. However, the underlying mechanism remains unclear. In this study, we investigated whether microglia-specific inhibition of GPR56, a member of the G protein-coupled receptor (GPCR) family, causes behavioral abnormalities in brain development. First, MIA induction did not affect the microglia population, but when examining the expression of microglial GRP56 in MIA-induced fetuses, GPR56 expression was inhibited between embryonic days 14.5 (E14.5) and E18.5 regardless of sex. Furthermore, microglial GPR56-suppressed mice showed abnormal behaviors in the MIA-induced offspring, including sociability deficits, repetitive behavioral patterns, and increased anxiety levels. Although abnormal cortical development such as that in the MIA-induced offspring were not observed in the microglial GPR56-suppressed mice, their brain activity was observed through c-fos staining. These results suggest that microglia-specific GPR56 deficiency may cause abnormal behaviors and could be used as a biomarker for the diagnosis and/or as a therapeutic target of behavioral deficits in MIA offspring.

• Toxicological Research
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• v.11 no.1
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• pp.91-101
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• 1995

A perinatal and postnatal study of KTC-1, a new semisyntheitic rifamycin antituberculous drug, was conducted in Sprague-Dawley rats. Dosages of KTC-1 0, 12, 27.6, and 63.5 mg/kg/day were administered to dams orally by gavage from day 17 of gestation to day 21 of lactation. All pregnant rats were allowed to deliver naturally for postnatal examination of their offspring. At 63.5 mg/kg/day, weakness, dark-red discharge around eyes, a loss in body weight, and a decrease in food and water consumption were observed in dams. An increase in the weight of adrenal gland and spleen, and a decrease in the weight of kidney and heart were also found. An increase in neonatal deaths during the lactation period, a loss in body weight, a delay in physical development, a decrease in traction ability, an increase in the number of errors and the time required for the multiple T-maze trial were found in F1 offspring. In addition, an increase in the incidence of visceral variations and retarded ossification were observed in F1 4 day old rats. An increase in the incience of skeletal anomalies was seen in F2 fetuses. There were no sings of maternal toxicity or embryotoxicity at 12 and 27.6 mg/kg/day. From the results mentioned above, it can be concluded that the no-effect dose levels(NOELs)for dams, F1 offspring, and F2 fetuses are 27.6 mg/kg/day.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.16 no.2
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• pp.211-218
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• 2005

Objectives : The purpose of the study was to evaluate the related factors of depression in mothers bringing their offspring for evaluation or treatment of problematic behaviors. Methods : Fifty mothers were recruited through their offspring's evaluation or treatment for offspring's problematic behaviors. Psychological tests battery including Korean Wechsler Adult Intelligence Scale and the Korean Educational Development Institute-Wechsler Intelligence Scale for Children was administered to all mothers and their offspring. Mothers completed Korean version of Child Behavior Checklist (K-CBCL), and teachers completed Teacher's Report Form (TRF). On the basis of the maternal depression, the mothers were divided into two groups. Results : 1) Among the fifty mothers, $42\%$ of the mothers had depressive disorder, $16\%$ had anxiety disorder, and $42\%$ had no psychiatric disorder. 2) Depressed mothers rated significantly higher in aggressive behaviors, externalizing problems of K-CBCL in their children. 3) Children of depressed mothers had lower score in picture arrangement and coding subtests of KEDI-WISC than those of no psychiatric disorder mothers. 4) After controlling for the total problematic behavior scores of TRF, mother's depression is positively correlated with aggressive behaviors, externalizing problems, total problematic behaviors of K-CBCL, and negatively correlated with coding of KEDI-WISC. Conclusion : Children's aggressive behavior, externalizing behavior, total problematic behaviors and low coding score may be associated with mother's depression.

• Toxicological Research
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• v.16 no.2
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• pp.117-124
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• 2000

The objective of this experiment is to investigate neurobehavioral and developmental effects of fumonisin B1 (FB1) after prenatal FB1 administration in rats. FB1 (0.8 or 1.6 mg/kg) was orally exposed to pregnant rats during gestational days 13 to 20, whereas the vehicle alone was administered to control group. Maternal and offspring body weights, physical landmarks of incisor eruption, eye opening, testes descending and vaginal opening, open field activity, running wheel activity, and complex maze performance were included as endpoints for developmental and neurobehavioral measurement. Maternal body weights were not signfficantly altered after FB1 exposure. Percentage of maternal weight gain difference between control and 1.6 mg/kg FBI groups was about 4%. Pre- and post-weanling weight of offsprings after prenatal exposure to FB1 was not signfficantly changed, suggesting that FB1 at 0.8 or 1.6 kg/kg doses may not cross the placenta. Significant gender difference in running wheel activity on postnatal days 57 to 63 and complex maze performance on postnatal days 75 to 78 was observed.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.130-136
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• 2005

The purpose of this study was to evaluate whether the interactions between maternal folate deficiency and methylenetetrahydrofolate reductase (MTHFR) polymorphism increase the risk of elevated maternal serum homocysteine, short gestation and reduced infant birthweight. Healthy pregnant (n = 170; 24-28 gestational weeks; 20-40 years old) women were analyzed for the MTHFR genotype and serum levels of folate and homocysteine, and were then followed for gestational age and infant birthweight. The mean infant birthweight was highest in mothers carrying MTHFR CC and with a normal folate range, and they were followed by mothers carrying MTHFR CT or TT and a normal range of folate or a folate deficiency. Birthweight was the lowest in mothers whose carrying MTHFR CC with folate deficiency. Using two way ANOVA, we found that folate level and the MTHFR polymorphism interacted to affect birth-weight of infants (p=0.05). Among those mothers carrying MTHFR CC, those with folate deficiency showed a 543 g reduction in infant birthweight compared with those with normal folate levels. However, infant birthweight was no different for mothers, those who with folate deficiency compared to those with normal range of folate among mothers carrying the MTHFR CT or TT genotypes. This study suggests an interaction between maternal serum folate and the MTHFR polymorphisms of the mother on the risk of delivering reduced birthweight offspring. Folate supplementation of folate deficient pregnant women with the MTHFR wild type is suggested to reduce the risk of low birthweight.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.77-81
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• 2001

Kamijadowhan (KMD), an oriental herbal medicine used for anti-angiogenic effect, was extracted with 80% ethanol from mixture of source materials and lyophilized. KMD was orally administered to plugpositive pregnant rats from gestational days 12 to 20, dividing into three groups including vehicle-treated control, 0.5 g/kg or 3 g/kg KMD-treated groups. Dam weight during gestation and post-gestation, weight of pre- and post-weaning offsprings in male and female, and reproductive and developmental endpoints including incisor eruption, eye opening and testes descent were measured. No significant alterations in development of physical landmarks in offspring, maternal weight gain during gestation and post-gestation, and offspring weight were observed in KMD-treated group. The measurement of organ weight at post-gestational days 21 was not changed in dams. In 0.5 g/kg KMD-treated rats, kidney weights in male and female offsprings were significantly increased, and the body weight in male offspring was also increased. Liver and brain weights were not changed. Taken together, these data suggest that KMD may not significantly cross the placenta and produce no reproductive and developmental toxicity at maternally non-toxic dosages.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.73-83
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• 2005

Higher methylmercury (MeHg) accumulation and susceptibility to toxicity in the fetus than in the mother at parturition is well known. However, the difference in MeHg exposure to fetus and offspring throughout gestation and suckling is not well established. In the human, the effects of MeHg exposure on pregnant and breast-feeding women remain an important issue for elucidation, especially those of continuous uptake in high-fish-consumption populations. The purpose of this paper was to evaluate the difference in MeHg exposure to fetus and offspring throughout gestation and lactation using our recent animal and human studies data. In the animal study, adult female rats were given a diet containing 5 ${\mu}$g/g Hg (as MeHg) for 8 weeks. Then they were mated and subsequently given the same diet throughout gestation and suckling. On embryonic days 18, 20, 22 and at parturition, the concentrations of Hg in the brains of fetus were approximately 1.5-2.0 times higher than those in the mothers. However, during the suckling period Hg concentrations in the brain rapidly declined to about 1/10 of that during late pregnancy. Hg concentrations in blood also decreased rapidly after birth. In human study, Hg concentrations in red blood cells (RBCs-Hg) in 16 pairs of maternal and umbilical cord blood samples were compared at birth and 3 months of age after parturition. RBCs-Hg concentration in the umbilical cords was about 1.6 times higher than those in the mothers at parturition. However, all the infants showed declines in Hg concentrations throughout the breast-feeding period. The Hg concentration in RBCs-Hg at 3 months of age was about half that at birth. Both the animal and human studies indicated that MeHg exposure to the fetus might be especially high but it dramatically decreases during the suckling period. Therefore, close attention should be paid to the gestation rather than the breast-feeding period to avoid the risk of MeHg to human infants.