• Clinical and Experimental Pediatrics
• /
• 제62권12호
• /
• pp.450-455
• /
• 2019

Background: Lipid accumulation product (LAP) is associated with the presence and severity of nonalcoholic fatty liver disease (NAFLD) in adults. Purpose: Here we evaluated the ability of LAP to predict NAFLD in obese children. Methods: Eighty obese children (38 girls; age 6-18 years) were included. Anthropometric measurements and biochemical values were obtained from the patients' medical records. LAP was calculated as [waist circumference (WC) (cm) - 58]×triglycerides (mmol/L) in girls; [WC (cm) - 65]×triglycerides (mmol/L) in boys. The minLAP and adjLAP were described (3% and 50% of WC values, respectively) and the total/high-density lipoprotein cholesterol index (TC/HDL-C) was calculated. NAFLD was observed on ultrasound, and patients were divided into 3 groups by steatosis grade (normal, grade 0; mild, grade 1; moderate-severe, grade 2-3). The area under the curve (AUC) and appropriate index cutoff points were calculated by receiver operator characteristic analysis. Results: LAP was positively correlated with puberty stage (rho=0.409; P<0.001), fasting insulin (rho= 0.507; P<0.001), homeostasis model assessment of insulin resistance (rho=0.470; P<0.001), uric acid (rho=0.522; P<0.001), and TC/HDL-C (rho=0.494; P<0.001) and negatively correlated with HDL-C (rho=-3.833; P<0.001). LAP values could be used to diagnose hepatosteatosis (AUC=0.698; P=0.002). The LAP, adjLAP, and minLAP cutoff values were 42.7 (P=0.002), 40.05 (P=0.003), and 53.47 (P= 0.08), respectively. For LAP, the differences between the normal and mild groups (P=0.035) and the normal and moderate-severe groups were statistically significant (P=0.037), whereas the difference between the mild and moderate-severe groups was not (P>0.005). There was a statistically significant difference between the normal and mild groups for adjLAP (P=0.043) but not between the other groups (P>0.005). There was no significant intergroup difference in minLAP (P>0.005). Conclusion: LAP is a powerful and easy tool to predict NAFLD in childhood. If LAP is ≥42.7, NAFLD should be suspected. This is the first study to assess LAP diagnostic accuracy for childhood obesity.

• 생명과학회지
• /
• 제27권6호
• /
• pp.708-725
• /
• 2017

전리방사선은 물질과 상호작용하여 원자내의 중성자나 양성자, 궤도전자를 충분히 제거시킬 수 있는 에너지이다. 이와 같은 전리방사선은 DNA이나 세포질 소기관과 세포질의 방사선 분해 생성물을 통해 직접적, 간접적으로 상호작용하여 분자구조를 변화시키는 산화적 대사를 일으킨다. 이러한 전리 현상은 분자수준에서 조직을 손상시키고, 세포 기능을 파괴할 수 있다. 따라서, 전리방사선에 의해 유도된 이온채널과 수송 변형이 보고되고 있다. 이러한 현상이 항상성을 유지하기 위한 생화학적 과정을 무너뜨리면, 유도된 생물학적 변화가 지속되고 후대로 영향을 미친다. 또한, 전리방사선의 영향으로 형성된 활성산소는 세포연접을 통해 인접세포로 퍼져 나갈 수 있다. 방사선량, 선량률, 선질에 따라 이러한 메커니즘이 충분히 방어할 수도 있고 그렇지 않을 수도 있다. 본 총설에서는 방사선생물학의 개념을 뒷받침하는 전리방사선의 세포수준에서 생물학적 효과에 대한 보고서를 간략히 알아보았다. 전리방사선의 생물학적 효과를 잘 이해하면 방사선을 잘 이용할 수 있고, 방사선피폭으로부터 더 나은 방호를 할 수 있을 것이다.

• 한국해양학회지:바다
• /
• 제9권4호
• /
• pp.196-203
• /
• 2004

한강 기수역에서 일어나는 지화학적 변화과정을 파악하기 위하여 2000년 6월과 2001년 2월 두 차례에 걸쳐 용존 무기영양염류,용존 유기 탄소,추출된 용존 유기물의 형광 특성, 용존 우라늄의 분포특성에 대해서 연구하였다. 용존 무기 영양염류는 염분이 증가함에 따라 감소하였는데,특히 질소계 영양염류의 경우 기수역에서 뚜렷한 질산화 과정(nitrification process)을 보였다. 인산-인 또한 질소계 영양염류와 같이 기수역에서 비보존적 분포특성을 보였다 용존 유기탄소와 형광 유기물은 염분이 증가함에 따라 감소하는 모습을 보였는데, 특히 5 psu이하의 저염분대에서 급격히 감소하는 양상을 나타내었다. 이러한 현상은 육상 기원의 지구거대 유기물질이 이온강도가 증가하는 기수역에서 응집, 침전하여 제거되기 때문으로 생각된다. 한편 용존 우라늄은 대부분 강을 통하여 해양으로 유입되는데, 염분이 증가함에 따라 같이 증가하는 양의 상관관계를 보였다. 용존 우라늄은 기수역에서 제거되는 비보존적인 분포 특성을 보였는데. 이는 용존 우라늄의 일부가 유기물질과 착화합물의 형태로 제거되기 때문으로 생각된다. 염분과 용존 우라늄의 분포 상관관계로부터 추정된 한강 기수역에서 용존 우라늄 제거량은 약 7.1 ton/year으로 Savannah salt marsh에서의 제거량과 비교해볼 때 약 51.4%에 해당하였다.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2002년도 춘계학술대회
• /
• pp.69-75
• /
• 2002

Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd/dwf3 were Shown to be blocked in $D^4$ reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bri1/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus it is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRI1 could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

• 한국의학물리학회지:의학물리
• /
• 제10권3호
• /
• pp.125-131
• /
• 1999

현재 임상적으로 쓰이고 있는 T$_1$/T$_2$ 강조영상 (weighted image) 은 각각 다른 조직이나 정상/병변 조직 사이에 정성적인 대조도를 준다. T$_1$/T$_2$ 영상화 (mapping)는 영상의 각 화소신호랄 T$_1$/T$_2$ 시간으로 나타내는 방법으로 병변의 진행정도를 정량적으로 알 수 있다. T$_1$/T$_2$ 영상화 (mapping)를 얻기 위해서는 수신신호의 증폭률이 같아야 하는데, 일반적으로 MR 영상화 장비에서는 A/D converter 의 동적 구간을 최대 활용하기 위하여 입력신호를 최대 증폭하기 때문에 각각 다른 수신 증폭률을 사용할 수 있다. 이 논문에서는 최대 증폭한 경우와 수신증폭률을 보정한 경우의 T$_1$/T$_2$ 영상을 각각 얻고 측정된 T$_1$/T$_2$ 값을 비교하여 수신증폭률 보정이 T$_1$/T$_2$ 영상화에 어떠한 영향을 미치는지 분석하였다. 그 방법으로서 얻은 영상들이 각각 다른 수신증폭률을 가진 경우에 이를 보정하기 위해 잡음을 표준편차로 이용하는 방법을 사용하였다. 이렇게 얻어진 머리의 T$_1$/T$_2$ 영상은 이미 보고된 T$_1$/T$_2$ 의 값과 유사하였다.

• 한국수산과학회지
• /
• 제31권6호
• /
• pp.852-858
• /
• 1998

1996년 7월 마산만의 해수를 0.8 $\mu$m filter에 여과한 여과액과 f/2배지에서 배양한 P. micans와의 혼합배양액에서 P. micans를 사멸시키는 해양세균을 분리하였다. 분리균의 형태학적 및 생화학적 검사와 균체지방산을 분석하여 동정한 결과 Pseudomonas 속으로 동정되어 Pseudomonas sp. LG-2로 명명하였으며, 그 살조특성을 조사한 결과는 아래와 같다. Pseudomonas sp. LG-2의 개체수와 배양여과액의 농도가 높을수록 P. micans의 사멸효과가 높게 나타났다. $1.3\times10^5,\;1.3\times10^6$ cells/ml의 농도로 접종한 시험관의 P. micans는 급격히 감소하여 배양 7일 후에는 $10^2$ cells/ml 이하로 사멸되었다. 또한, 배양석과액의 최종농도가 $30\%$일 경우에는 급격히 감소하여 배양 3일 후 거의 사멸하였다. Pseudomonas sp. LG-2의 성장시기에 따른 배양여과액의 사멸효과는 잠복기의 경우 P. micans의 성장에 큰 영향을 미치지 않았으나, 대수증식기 중기의 배양여과액은 접종 5일 후 P. micans의 개체수를 1/2로 감소시켰으며, 정상기의 배양여과액은 접종 후 급격히 감소시켜 배양 3일 후 대부분 사멸시켰다. Alexandrium tamarense, Prorocentrum micans, Scrippsiella trochoidea, Gymnodinium sanguineum, Cochlodinium polykrikoides의 5종의 적조원인 편모조류에 대한 Pseudomonas sp. LG-2의 살조특이성은 P. micans와 S. trochoidea에 살조효과를 나타내었다.

• 한국가축번식학회지
• /
• 제18권4호
• /
• pp.235-244
• /
• 1995

생쥐 배반포기 내부세포괴를 체외에서 분리 배양하여 분화가 억제된 내부세포괴 유래 증식세포를 미분화 상태에서 무한히 증식할 수 있는 전능성을 지닌 배아간세포(embryonic stem cell : ES cell)로 확립하고자 본 연구를 실시하였다. BCF1 생쥐 배반포를 10% FCS, 0.1mM nonessential amino acid, 0.1mM sodium pyruvate, 0.1mM 2-mercaptoethanol과 1,000U/ml LIF(세포분확억제인자)가 첨가된 DMEM 기초배양액에 mitomycin-C를 처리한 STO 단층배양세포에서 배양하여 분화가 억제된 내부세포괴 유래의 배아간세포를 분리하였다. 배반포를 STO 단층배양세포에서 4일간 배양하여 내부세포괴세포를 신선한 STO 단층배양세포에서 약 5일 간격으로 반복하여 계대배양을 실시하였다. 5차 계대배양후 뚜렷한 분화 양상없이 배양된 미분화 세포군에 대한 alkaline phosphatase (AP)염색과 체외분화능 검색을 실시한 결과 적색의 미분화 AP 양성반응이 확인되었으며 체외에서 배분화 형성이 유도됨에 따라 배양된 배아간세포주의 다능성 배아간세포 특성을 확인할 수 있었다.

• Toxicological Research
• /
• 제22권4호
• /
• pp.381-390
• /
• 2006

Astaxanthine is a pigment that belongs to the family of the xanthophylls, the oxygenated derivatives of carotenoids whose synthesis in plants derives from lycopene. Astaxanthine is also a carotenoid widely used in salmonid and crustacean aquaculture to provide the pink color characteristic of that. Recent study reported that astaxanthine has the role as a detoxicant against the free radicals. On our study, we estimated the genotoxicity in ICR mice and possibility as antioxidant reagents of mutant Phaffia rhodozyma strain over expressing the astaxanthine by gamma-lay and carophyll pink including astaxanthine in apoE knock out mice, respectively. In our study, we administered Phaffia rhodozyma (2 mg and 3 mg) and carophyll pink for 4 and 8 week. The clinical sign and mortality were not detected compared with control groups. In the mutant frequency of hprt gene and chromosome aberration in splenic cells, there was not detected abnormality. There was not critical change in hematological and serum biochemical test compared to control. In expression level of repair enzyme, increase of catalase were detected and increase of expression level of Nrf-2 was detected in Phaffia rhodozyma (3 mg) and carophyll pink in 8 week treated group. In GSH level, the group of treated with Phaffia rhodozyma (3 mg) showed the increase of the GSH. In conclusion, mutant Phaffia rhodozyma and caphyll pink may be applied to the effective food additives to reduce the free radical.

• Journal of Plant Biotechnology
• /
• 제29권2호
• /
• pp.139-144
• /
• 2002

Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd /dwf3 were shown to be blocked in D$^4$reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bril/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus it is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRIl could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

• 한국환경성돌연변이발암원학회지
• /
• 제21권1호
• /
• pp.1-8
• /
• 2001

We have synthesized $^{99m}$Tc-mercaptoacetyltriglycine (MAG3)-biocytin as a new imaging agent for hepatobiliary scintigraphy. The aim of this study was to evaluate the usefulness of $^{99m}$Tc-MAG3-biocytin scintigraphy in differentiating carbon tetrachloride ( $CCl_4$)-induced hepatotoxicity from $\alpha$-naphthylisothiocyanate (ANIT)-induced cholestasis in mice, which reflecting the differential diagnosis of neonatal jaundice caused by neonatal hepatitis from congenital biliary atresia in humans. Methods: Balb/c mice (female, 20 g, n=4-6) were pretreated with $CCl_4$(0.5 or $1.0m\ell$/kg) and ANIT ($150 or 300 m\ell$/kg) 18 h before scintigraphy. Biochemical and histopathological examinations showed a pattern of typical acute hepatitis (increase of transaminases and hepatocellular necnsis) in $CCl_4$-treated mice and cholestasis (increase of alkaline phosphatase and ${\gamma}$-glutamyltransferase, and biliary hyperplasia) in ANIT-treated mice, respectively, Mice were fasted at least 4 hr prior to the intravenous injection of $^{99m}$Tc-MAG3-biocytin (18.5 MBq/20$\mu\textrm{g}$) in 2% human serum albumin in saline. Scintigraphy was performed with a ${\gamma}$-camera equipped with a 1-mm diameter pin-hole collimator for 30 min and images were acquired every 15 s. We compared the values of physical parameters, such as peak liver/heart ratio ($${\gamma}$_{max}$) and peak ratio time ($t_{max}$) far $^{99m}$Tc-MAG3-biocytin scintigraphy. Results: Scintigraphic parameters of the $CCl_4$-pretreated (0.5 $m\ell$/kg) group showed a 81.9% decrease of r$_{max}$, and 42.2% decrease of $t_{max}$, whereas the ANIT-pretreated ( $150m\ell$/kg) group showed a 53% decrease of $r_{max}$, and 2.36-fold increase of $t_{max}$, (P<0.05). These results demonstrate that the decrease of $r_{max}$ and the shortening of $t_{max}$ are characteristic features for hepatotoxicity, in contrast to the increase of $t_{max}$ and decrease of $r_{max}$ for biliary hyperplasia. Conclusion: $^{99m}$Tc-MAG3-biocytin hepatobiliary scintigraphy can distinguish hepatitis from cholestasis in mice model and may be similarly useful in humans which differentiating the cause of neonatal jaundice in clinical study.cal study.cal study.cal study.