• 대한수의학회지
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• 제39권6호
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• pp.1161-1167
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• 1999

To investigate the effect of diazepam on fetal development in pregnant rats, this experiment was performed in eighty Sprague-Dawley female rats which were 8 weeks old and grouped into two according to different diazepam treatment period during 5-9 days of gestation and 10-14 days of gestation. Both experimental groups were included by saline treated groups (control) and diazepam-treated groups (6mg, 12mg and 24mg), respectively. Diazepam was injected to pregnant rats subcutaneously, which were sacrified on 20 days of gestation and mean litter size, fetal body weight, fetal crown-rump length (CRL) and pathological findings were examined. 1. Concerning mean litter size, diazepam-treated groups showed lower mean litter size than control in both 5-9 days and 10-14 days of gestation groups(p < 0.05) without difference according to dosage of diazepam and day of gestation. 2. Concerning fetal body weight, diazepam-treated groups during 5-9 days of gestation showed lower fetal body weight than control and the other treated group during 10-14 days(p < 0.01) without difference according to dosage of diazepam. Diazepam-treated group during 10-14 days of gestation showed no difference among experimented groups. 3. Concerning fetal crown-rump length (CRL), diazepam-treated groups during 5-9 days of gestation showed shorter CRL than control and the other treated group during 10-14 days of gestation(p < 0.01) without difference according to dosage of diazepam. 4. Reduction of mean litter size, fetal body weight and CRL was shown from when treated by the dosage of 6mg/kg of diazepam. 5. Maternal mortality according to dosage of the 20mg/kg of diazepam were 30% and 20% in the treated group during 5-9 days and 10-14 days of gestation, respectively. These results indicated that diazepam treatment in pregnant rats caused considerable reduction of mean litter size, fetal body weight and fetal crown-rump length when treated during 5-9 days of gestation.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.854-861
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• 1999

Seventeen pregnant ewes (8 superovulated and 9 non-superovulated) were used to study correlations of maternal serum progesterone concentrations with uterine and fatal weights at weeks 7 and 15 of pregnancy. Statistical analyses indicated that uterine growth during the first 7 weeks of pregnancy highly associated with maternal serum progesterone concentration (r=0.87 and 0.85, with wet and dry uterine weights, respectively). Ewes with higher maternal serum progesterone concentrations had higher total and average fetal weights at week 7 of pregnancy (r=0.89 and 0.86, respectively). At week 7 of pregnancy, wet and dry uterine weights highly correlated (p<0.01) with total and average fatal weights (r=0.99 and 0.80, 0.98 and 0.75, respectively). Maternal serum progesterone concentrations, however, did not correlate (p>0.05) with wet and dry uterine weights (r=0.36 and 0.47, respectively) and with total and average fetal weights (r=0.20 and 0.58, respectively) at week 15 of pregnancy. However, wet and dry uterine weights had high correlation with total fetal weight (r=0.97 and 0.95, respectively), without significant correlation with average fetal weight. It was concluded that during the embryonic stage of pregnancy, the levels of maternal progesterone were highly correlated with uterine and fetal growths, while during the fetal stage pregnancy, the correlation became less evident.

• 한국환경보건학회지
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• 제46권4호
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• pp.368-375
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• 2020

Objectives: Some animal studies have reported that methyl mercury causes developmental toxicities such as placental and fetal weight loss, but the mechanism is still unclear. This study aimed to investigate the developmental toxicities of methyl mercury, focusing on placental endocrine function and fetal growth retardation in rats. Methods: Positively same-time-mated female Sprague-Dawley rats were purchased on gestational day (GD) eight and treated with 0, 5, 10 and 20 ppm of methyl mercury (n=5) dissolved in tap water from GD eight through 19. During treatment, the drinking water (methyl mercury) intake and body weight of each pregnant rat was measured daily. On day 19, caesarean sections were performed and blood samples were collected. Developmental data such as placental and fetal weights, fetus numbers, and placental efficiency (fetal weight/placental weight) were also collected. Placental prolactin-growth hormone (PRL-GH) family, such as placental lactogen (PL) -Iv, II, and prolactin-like protein (PLP) -B, levels in serum were analyzed by ELISA. Also, placental tissues were assigned to histochemistry. Results: The mean cumulative methyl mercury exposure for the 5, 10, and 20 ppm groups were 2.37, 4.63, and 9.66 mg, respectively. The mean daily exposure of the 5, 10, and 20 ppm groups were 0.24, 0.47, and 0.97 mg, respectively. Maternal body weight increased in accordance with GD. There was no significant difference in weight gain among the experimental groups. Histopathologic changes were not observed in placental tissues among the experimental groups. However, mean placental and fetal weights were lower in the 10 and 20 ppm exposed groups compared to the control. Placental efficiency was also lower in the 10 and 20 ppm exposed groups compared to the control. Serum PL-Iv and II levels were lower in the 10 and 20 ppm exposed groups than the control, in accordance with the changing pattern of placental and fetal weights and placental efficiency. Conclusion: The inhibitory effects of methyl mercury on the serum levels of placental PRL-GH family such as PL-Iv and II may be secondary leads to the reduction of placental efficiency and fetal growth retardation in rats.

• Asian-Australasian Journal of Animal Sciences
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• 제21권5호
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• pp.640-647
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• 2008

Breed differences in adult animals are determined during fetal development. If interventions are to be developed that influence growth of muscle and fat, it is important to know at which time during gestation breed differences appear and are fixed. The objective of this study was to characterize fetal development in cattle of different breeds. Pregnant cows of 4 cattle breeds with different growth impetus and muscularity were slaughtered under normal processing conditions and the fetuses were removed. German Angus, a typical beef cattle; Galloway, a smaller, environmentally resistant beef type; Holstein Friesian, a dairy type; and Belgian Blue, an extreme type for muscle growth were used. Fetuses of each breed were investigated at 3, 6, and 9 mo of gestation. Fetuses were weighed and dissected into carcass, organs, and muscles. Body fat weight was obtained using the Soxhlet extraction method. Fetal weight increased most rapidly in the third trimester of gestation mainly due to the accelerated muscle and fat deposition. The organ weight to body weight (BW) ratios decreased and the muscle and fat weight to BW ratios increased. At 3 mo of gestation, Galloway fetuses had the significantly smallest BW, half-carcass weight, leg weight, organ weight, muscle weight and shortest leg length. In contrast, Holstein fetuses had the significantly greatest BW, liver, kidney, and lung weights and significantly longest leg length among the 4 breeds, but no differences between Holstein Friesian and Belgian Blue were detected in half-carcass and leg weight. Indeed, Belgian Blue fetuses had the significantly greatest half-carcass weight, leg weight, and muscle weight at 9 mo of gestation, and Galloway had a significantly greater body fat to BW ratio than Holstein Friesian and Belgian Blue. These differences were not evident at 3 and 6 mo of gestation. These data show that the profound increase of tissue and organ weights occurred in later gestation in cattle fetuses even though breed differences were evident as early as 3 mo of gestation. Depending on the tissue of interest, impacting fetal growth likely needs to occur early in gestation before the appearance of breed-specific differences.

• 대한간호학회지
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• 제41권2호
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• pp.276-283
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• 2011

Purpose: Prenatal depression is associated with potential negative consequences for the mother and infant. The purpose of this study was to examine pregnant women's stress, and depression and their impact on maternal-fetal attachment and fetal growth. Methods: Data were collected by means of a questionnaire and fetal sonogram from a convenience sample of 166 pregnant women. Results: Women who have a low educational level, poor health and are dissatisfied with their marriage showed low maternal-fetal attachment. Prenatal depression had significant correlations with length of pregnancy and level of stress. Even though correlation between maternal stress and fetal weight (r=-.15, p=.099) and correlation between maternal depression and maternal-fetal attachment (r=-.13, p=.095) were not statistically significant, the impact of the prenatal psychological state of mothers can not be ignored as it relates to fetal health. Conclusion: Maternal-fetal attachment and fetal growth can be affected by maternal emotional state, including stress or depression. These findings suggest that primary care nurses in hospitals and public health centers should provide prenatal depression screening and nursing intervention programs for management and prevention of prenatal stress and depression.

• Parasites, Hosts and Diseases
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• 제53권2호
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• pp.189-196
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• 2015

The sequestration of infected erythrocytes in the placenta can activate the syncytiotrophoblast to release cytokines that affect the micro-environment and influence the delivery of nutrients and oxygen to fetus. The high level of IL-10 has been reported in the intervillous space and could prevent the pathological effects. There is still no data of Th17 involvement in the pathogenesis of placental malaria. This study was conducted to reveal the influence of placental IL-17 and IL-10 levels on fetal weights in malaria placenta. Seventeen pregnant BALB/C mice were divided into control (8 pregnant mice) and treatment group (9 pregnant mice infected by Plasmodium berghei). Placental specimens stained with hematoxylin and eosin were examined to determine the level of cytoadherence by counting the infected erythrocytes in the intervillous space of placenta. Levels of IL-17 and IL-10 in the placenta were measured using ELISA. All fetuses were weighed by analytical balance. Statistical analysis using Structural Equation Modeling showed that cytoadherence caused an increased level of placental IL-17 and a decreased level of placental IL-10. Cytoadherence also caused low fetal weight. The increased level of placental IL-17 caused low fetal weight, and interestingly low fetal weight was caused by a decrease of placental IL-10. It can be concluded that low fetal weight in placental malaria is directly caused by sequestration of the parasites and indirectly by the local imbalance of IL-17 and IL-10 levels.

• Journal of Preventive Medicine and Public Health
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• 제19권1호
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• pp.123-129
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• 1986

다태동물의 경태반성독성학실험시 자중내적 요인의 하나로서 자궁내 착상위치가 태자의 출생시 체중에 미치는 영향을 관찰하고, 급 만성 일산화탄소중독으로 저산소상태를 만들었을 때 이러한 외부 요인이 자궁내적 요인에 어떻게 작용하는가를 관찰하고자 백서를 이용하여 정상대조군 및 급 만성 일산화탄소 폭로군에서의 착상부위별 태자의 출생시 체중을 관찰한 바 다음과 같은 소견을 얻었다. 1) 대조군에 있어서는 자궁중앙부에 위치한 태자가 가장 무거운 출생시체중을 나타내었으며 그 다음이 자궁경부, 난소부의 순서였다. 그러나 부위별 체중은 통계적으로 유의한 차이를 보이지 않았다. 2) 급성 CO폭로군에서는 자궁중앙부의 태자체중이 가장 무겁고 자궁경부, 난소부의 순서로 대조군과 양상이 같았으나, 부위별 태자체중의 차이는 통계적으로 유의하였다. 만성 CO 폭로군에서는 자궁중앙부, 난소부, 자궁경부의 순서였으며 자궁부위별 태자체중의 차이는 유의하였다. 이상의 결과를 통하여 정상상태에서는 태자의 자궁내위치는 출생시 체중에 영향을 주지 않으나, 급 만성 CO중독으로 조직저산소증을 일으킨 경우에는 자궁내 착상부위에 따라 태자의 출생시 체중에 영향을 주는 것으로 나타나 다태동물의 출생시 체중을 종속변수로 사용하는 실험연구에서는 태자의 자궁내 착상부위가 교란변수로서 간주되어야 할 것으로 생각된다.

• Toxicological Research
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• 제17권4호
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• pp.279-286
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• 2001

Recently, there is an increasing nationwide concern in Korea that exposure to electric and magnetic fields in the home environment may not be safe in humans. To identify possible effects of horizontally polarized magnetic fields (MF) exposure on embryo-fetal development, timed-mated female Sprague-Dawley rats (24/group) received continuous exposure to 60 Hz MF at field strengths of 0 Gauss (sham control), 50mG,833 mG, or 5000 mG. Dams received MF of sham exposures for 22hr/day on gestation days 6 through 20. Experimentally generated MF were monitored continuously througout the study. There was no evidence of maternal toxicity of developmental toxicity in any MF-exposed groups. Mean maternal body weight, organ weights, and gross findings in groups exposed to MF did not differ from those in sham control. No significant differences in fetal deaths, fetal body weight, and placental weight were observed between MF-exposed groups and sham control. External, visceral, and skeletal examination of fetuses demonstrated no significant differences in the incidence of fetal malformations between MF-exposed and sham control groups. In conclusion, exposure of pregnant Sprague-Dawley rats to 60 Hz at MF strengths up to 5000 mG during gestation day 6-20 did not produce any biologically significant effect in either dams of fetuses.

• 한국임상수의학회지
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• 제18권2호
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• pp.146-151
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• 2001

This study was carried out to find if the X-irradiation being used for clinical diagnosis during pregnancy would affect fetal development and cause fetal malformation in rats or not. To determine the dose and irradiation frequency of X-irradiation and gestation period by which fetal development would be affected when irradiated during pregnancy, seventy-two Sprague Dawley female rats (8 weeks old) were used for the experiment and grouped into three according to different gestation period of 5-8 days, and 6-12 days of gestation. Experimental rats were irradiated on the daily irradiation conditions of 40, 60, 80 kvp(kilo volt peak), 150 mA(milliampere), 0.25 sec and 4 times/day for both 5-8 days and 10-13 days of gestation, and 100 kvp, 100 mA, 2 min. and 4 times/day for 6-12 days of gestation. Rats were put in a small dark box when irradiated, which animals were sacrificed on the 20th day of gestation and mean litter size, fetal body weight, fetal crown-rump length(CRL) were investigated along with pathological findings. 1. Litter size were significantly decreased in the rats which were irradiated by both 60 and 80 kvp during 5 to 8 days of gestation and by 100 kvp during 6-12 days of gestation compared to those from the control rats(p<0.05) 2. Fetal body weight was significantly decreased in the fetus from the rats which were irradiated by both 60-80 kvp during 5-8 days of gestation and by 100 kvp during 6-12 days of gestation compared to those from the control rats(p<0.05). 3. There was no significant difference of fetal crown-rump length between all the experimental rats and the controls. 4. Fetal absorption, fetal death, and fetal malformation were not observed in the fetus form the rats irradiated by 40-80 kvp during 5-8 and 10-13 days of gestation, however, the pathological findings were found in those from the rats irradiated by 100 kvp during 6-12 days of gestation. 5. The harmful effect of x-irradiation on fetal development was estimated to occur when irradiated during 5-8 days of gestation. These results indicated that even X-irradiation for clinical diagnosis could affect fetal development in the early embryonic stage and when the fetus were exposed to frequent and prolonged x-irradiation with over dose.

• 여성건강간호학회지
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• 제5권2호
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• pp.191-203
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• 1999

A clinical study was made on 365 low birth weight infant and 406 normal birth weight infant who had been born at Kangnam St. mary's Hospital during past 3 years from Jan. 1, 1995 to Dec. 31, 1997. the data of this study were gathered through reviewing of medical records. 1. Comparison of general characteristic with of obstetric characteristic 1) Old maternal age, previous abortion and previous LBWI delivery in the group of low birth weight infant(LBWI) mother were more prevalent than those in the group of normal birth weight infant(NBWI)mother 2) Cesarean section, abnormal presentation and multiple pregnancy in the group of LBWI mother were prevalent than those in the group of NBWI mother. 3) regular antenartal care and visiting rate of tertiary hospital in the group of LBWI mother were more prevalent than those in the group of NBWI mother. 2. Frequency of low birth weight infant 1) Anmual average frequency of LBWI was 6.5% and monthly frequency was the highest in January and december. 2) The frequency of LBWI was the highest in 37-40wks of gestational age and was the highest in 2251-2500 gm of birth weight. 3) The frequency of congenital anomaly in the group of LBWI was more prevalent than that of NBWI. 3. Mortality rate of LBWI The mortality rate of LBWI was 9.2%. The highest mortality rate was noted before 27wks of gestational age, less than 1000gm of birth weight and within 12hrs of delivery. 4. The most common complication of pregnant women was pre-term labor, the most complication relating to placenta was premature rupture of membrane(PROM) and the most fetal complication was fetal distress in delivered LBWI. 5. Significant relating factors of low birth weight infant delivery were associated with maternal age, previous delivery, previous low birth weight delivery, pre-eclampsia, anemia, oligohydramnios, PROM, placenta previa, abruptio placenta, fetal sex, fetal distress and congenital anomaly.