• Journal of Genetic Medicine
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• 제12권2호
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• pp.100-108
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• 2015

Purpose: Conventional methods for the prenatal detection of fetal RhD status involve invasive procedures such as fetal blood sampling and amniocentesis. The identification of cell-free fetal DNA (cffDNA) in maternal plasma creates the possibility of determining fetal RhD status by analyzing maternal plasma DNA. However, some technical problems still exist, especially the lack of a positive control marker for the presence of fetal DNA. Therefore, we assessed the feasibility and accuracy of fetal RHD genotyping incorporating the RASSF1A epigenetic fetal DNA marker from cffDNA in the maternal plasma of RhD-negative pregnant women in Korea. Materials and Methods: We analyzed maternal plasma from 41 pregnant women identified as RhD-negative by serological testing. Multiplex real-time PCR was performed by amplifying RHD exons 5 and 7 and the SRY gene, with RASSF1A being used as a gender-independent fetal epigenetic marker. The results were compared with those obtained by postnatal serological analysis of cord blood and gender identification. Results: Among the 41 fetuses, 37 were RhD-positive and 4 were RhD-negative according to the serological analysis of cord blood. There was 100% concordance between fetal RHD genotyping and serological cord blood results. Detection of the RASSF1A gene verified the presence of cffDNA, and the fetal SRY status was correctly detected in all 41 cases. Conclusion: Noninvasive fetal RHD genotyping with cffDNA incorporating RASSF1A is a feasible, reliable, and accurate method of determining fetal RhD status. It is an alternative to amniocentesis for the management of RhD-negative women and reduces the need for unnecessary RhIG prophylaxis.

• Journal of Genetic Medicine
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• 제14권1호
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• pp.1-7
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• 2017

Purpose: The aim of this study was to assess the diagnostic efficacy of noninvasive prenatal screening for trisomy 18 by assessing the levels of unmethylated-maspin (U-maspin) and fetal nuchal translucency (NT) thickness during the first trimester of pregnancy. Materials and Methods: A nested case-control study was conducted using maternal plasma samples collected from 65 pregnant women carrying 11 fetuses with trisomy 18 and 54 normal fetuses. We compared the U-maspin levels, NT thicknesses, or a combination of both in the first trimester between the case and control groups. Results: U-maspin levels and NT thickness were significantly elevated in the first trimester in pregnant women carrying fetuses with trisomy 18 when compared to those carrying normal fetuses (27.2 vs. 6.6 copies/mL, P<0.001 for U-maspin; 5.9 vs. 2.0 mm, P<0.001 for NT). The sensitivities of the U-maspin levels and NT thickness in prenatal screening for fetal trisomy 18 were 90.9% and 90.9%, respectively, with a specificity of 98.1%. The combined U-maspin levels and NT thickness had a sensitivity of 100% in prenatal screening for fetal trisomy 18, with a specificity of 98.1%. Conclusion: A combination of U-maspin levels and NT thickness is highly efficacious for noninvasive prenatal screening of fetal trisomy 18 in the first trimester of pregnancy.

• 대한핵의학회지
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• 제38권2호
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• pp.198-204
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• 2004

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used $^{18}F$-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. $[^{11}C]Thymidine$ was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of $^{11}C$ and rapid metabolism of $[^{11}C]Thymidine$ in vivo make the radiotracer less suitable for routing use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicing but the image qualify and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog $3'-deoxy-3'-^{18}F-fluorothymidine$ (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. $[^{18}F]FLT$ is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. $[^{18}F]FLT$ PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and $[^{11}C]choline$, which is a new marker for cellular proliferation.

• BMB Reports
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• 제41권10호
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• pp.685-692
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• 2008

Colorectal cancer (CRC) is the third most common malignancy in the world. Because CRC develops slowly from removable precancerous lesions, detection of the disease at an early stage during regular health examinations can reduce both the incidence and mortality of the disease. Although sigmoidoscopy offers significant improvements in the detection rate of CRC, its diagnostic value is limited by its high costs and inconvenience. Therefore, there is a compelling need for the identification of noninvasive biomarkers that can enable earlier detection of CRC. Accordingly, many validation studies have been conducted to evaluate genetic, epigenetic or protein markers that can be detected in the stool or in serum. Currently, the fecal-occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics combined with developments in other relevant fields will lead to the discovery of novel non invasive biomarkers whose usefulness will be tested in larger validation studies. Here, non-invasive molecular biomarkers that are currently used in clinical settings and have the potential for use as CRC biomarkers are discussed.

• Journal of Genetic Medicine
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• 제8권1호
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• pp.1-16
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• 2011

현재 사용되고 있는 침습적 산전진단법(양수천자, 융모막샘플링)은 1-2%의 태아 손실이 초래되어, 비침습적 산전진단법이 산전진단의 궁극적인 목표로 대두되어 왔다. 1997년 Dr. Lo에 의해서 임신부 혈장 내에 세포 유리 태아 DNA (cffDNA)의 존재가 발견된 후 비침습적 산전진단의 새로운 가능성이 열렸으며, 과거 10년간 이에 대한 연구의 많은 진전을 보여주고 있다. 최근에 cffDNA를 이용한 Hemophilia A와 듀센형 근이영양증 등 반성 유전병(X-linked disorders) 진단에 필수적인 산전태아의 성 판정과 RhD-음성 임신부에서 태아의 RhD유전자 핵형 분석 등이 이미 외국에서 임상적으로 적용되고 있으나, 한국에서는 아직 실용화되지 않고 있다. CffDNA의 임상 사용에는 여전히 많은 제약점이 있으며, 이는 임신부 혈장 내 cffDNA 양에 비해 많은 양의 모태 DNA가 존재하고, 종래에 사용되었던 특이적인 Y염색체 유전자(Y-specific gene)는 남아 태아 임신 시에만 적용된다는 것에 기인한 다. 따라서 모든 태아에 적용할 수 있는 태아 성과 무관한 마커(sex-independent universal fetal marker as internal positive controls)가 요구되며, 이를 이용하여 정확한 태아 DNA를 검출할 수 있다. 본 연구진은 국내 처음으로 임신부 혈장 내에 cffDNA를 이용하여 SRY 유전자, RhD-exon 7, 태아 성과 무관한 DNA마커(universal fetal DNA marker)로써 RASSF1A 유전자를 실시간 중합효소연쇄반응(RT- PCR)을 사용하여 뛰어난 결과를 얻었다. 이는 한국에서 처음으로 성공적으로 시도된 것이다. 연구결과에서 산전 태아 성 판별과 산후 태아의 성이 100% 일치하였으며, 임신 주기별 SRY 수치는 임신이 진행할수록 증가함을 확인할 수 있었다. 따라서 이러한 방법은 혈우병 A, 듀센형 근이영양증, 선천성 부신증식증과 연골 무형성증의 진단과 치료 상담에 이용할 수 있으며 50%에서 침습적인 방법을 줄일 수가 있다. 또한, RhD-음성 임신부 대상으로 태아의 성 판정과 RhD 태아 유전자형을 분석한 결과 RhD-음성 태아를 정확히 검출함으로써 앞으로 기존 양수천자 등 침습적 검사를 대체할 수 있을 것이다. 특히 이는 치료가 필요 없는 RhD-음성 태아에서 RhD-면역글로불린의 예방적 치료를 사전에 막을 수 있어, 임신부 건강을 보호하고 의료 비용을 줄일 수 있는 큰 장점을 가진다. 한국에서 최초로 시도된 임신부 혈장 내 cffDNA를 이용한 본 연구의 성공은 비침습적 산전진단 임상 적용의 새 길을 제시하였다. 따라서 이를 각 유전질환의 산전진단에 유용하게 활용하는 것은 태아와 임신부의 건강 증진과 의료비용 절약 등 개인과 국가에 많은 기여를 할 것으로 사료된다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권2호
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• pp.79-87
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• 2024

Purpose: Recently, the prevalence of eosinophilic gastrointestinal disease (EGID) has shown an increasing trend worldwide. As the diagnosis of EGID requires invasive endoscopy with biopsy, noninvasive markers for detecting EGID in suspected patients, particularly children, are urgently needed. Therefore, this study aimed to evaluate the diagnostic accuracy of serum eosinophil cationic protein (ECP) beyond peripheral eosinophil counts in pediatric patients with EGID. Methods: Overall, 156 children diagnosed with EGID were enrolled and 150 children with functional abdominal pain disorder (FAPD) were recruited as controls. All participants underwent endoscopic biopsy in each segment of the gastrointestinal (GI) tract and serum ECP measurement, as well as peripheral eosinophil percent and absolute eosinophil count. Results: Comparing EGID (n=156) with FAPD (n=150) patients, serum ECP levels were significantly higher in pediatric patients with EGID than in those with FAPD (25.8±28.6 ㎍/L vs. 19.5±21.0 ㎍/L, p=0.007), while there was no significant difference in peripheral eosinophil percent and absolute eosinophil counts between the two groups. Serum ECP levels were correlated with peripheral eosinophil percent (r=0.593, p<0.001) and the absolute eosinophil count (r=0.660, p<0.001). The optimal cutoff value of serum ECP for pediatric EGID was 10.5 ㎍/mL, with a sensitivity of 69.9% and a specificity of 43.4% with an area under the receiver operating characteristic curve of 0.562. Conclusion: The combination of serum ECP levels and peripheral eosinophil counts, when employed with appropriated thresholds, could serve as a valuable noninvasive biomarker to distinguish between EGID and FAPD in pediatric patients manifesting GI symptoms.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권4호
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• pp.236-245
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• 2024

Purpose: The prevalence of nonalcoholic steatohepatitis (NASH) is increasing with the increasing prevalence of childhood obesity. Although NASH has a high risk of progression to liver fibrosis and cirrhosis, few studies have reported noninvasive markers for predicting hepatic fibrosis in children. This study aimed to evaluate and compare the diagnostic accuracies of serologic biomarkers and scoring systems for hepatic fibrosis in obese children with NASH. Methods: A total of 96 children were diagnosed with NASH based on liver biopsy findings and divided into two groups according to the degree of liver fibrosis: mild (stage 0-1) or advanced (stage 2-4). Clinical and laboratory parameters and serum levels of hyaluronic acid and type IV collagen were measured. The aspartate aminotransferase/platelet ratio index (APRI) and fibrosis-4 (FIB-4) score were calculated. Results: Among the noninvasive markers, only serum type IV collagen level and FIB-4 were significantly different between the two groups. The area under the receiver operating curve of each biomarker and scoring system was 0.80 (95% confidence interval [CI]: 0.70-0.90) for type IV collagen at an optimal cutoff of 148 ng/mL (sensitivity 69.8%, specificity 84.6%), followed by 0.69 (95% CI: 0.57-0.83) for APRI, 0.68 (95% CI: 0.56-0.80) for FIB-4, and 0.65 (95% CI: 0.53-0.77) for hyaluronic acid. Conclusion: Type IV collagen as a single noninvasive serologic biomarker for hepatic fibrosis and FIB-4 as a hepatic fibrosis score are beneficial in predicting advanced hepatic fibrosis and determining proper diagnosis and treatment strategies before fibrosis progresses in obese children with NASH.

• 대한의생명과학회지
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• 제3권2호
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• pp.151-160
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• 1997

본 연구는 카드뮴의 이용 및 환경 오염의 증가로 일어날 수 있는 카드뮴 중독에 대한 새로운 생물학적 지표로서의 요중 ascorbic acid를 평가하기 위하여 실험적으로 중독시킨 Sprague-Dawley종의 흰쥐를 이용하여 요중 ascorbic acid측정, 신장의 조직병리학적 조사 및 생화학적 간 기능 검사를 실시하였다. 측정 된 요중 ascorbic acid 농도의 전 실험기간 (50일) 평균치는 실험군I (카드뮴 100 ppm)이 214.0 mg/dl, 실험군II (카드뮴 200 ppm)가 254.3 mg/dl로 대조군 9.0 mg/dl에 비해 각각 24배 및 28배의 증가를 보였다. 조직병리학적 소견으로는 신장의 근위 세뇨관에서 단백뇨의 원인으로 추정되는 호산성 초자양 물질이 관찰되어 신장의 손상이 있었고, 생화학적 분석에서 실험군I에서 AST, ALT의 수치가 대조군의 143 mg/dl, 50 mg/dl에 비해 각각 199 mg/dl, 88 mg/dl, 실험군II가 270 mg/dl, 226 mg/dl로 나타나 간 기능의 손상이 있었음을 알 수 있었다. 이상의 결과로 실험동물이 카드뮴에 노출됨에 따라 그 아만성 독성으로서 간장 및 신장 기능의 손상이 있었고 또한 요중의 ascorbic acid가 현저하게 증가되어 요중 ascorbic acid가 실험 동물의 카드뮴 노출에 대한 noninvasive 진단 지표로서 활용될 수 있을 것으로 기대된다.

• Clinical and Experimental Pediatrics
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• 제56권10호
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• pp.424-430
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• 2013

Exhaled nitric oxide (NO) has been extensively investigated as a noninvasive marker of airway inflammation in asthma. The increased NO expression induced by inflammatory mediators in airways can be monitored easily in exhaled air from asthmatic children. Based on the relationship between the increased NO expression and eosinophilic airway inflammation, fractional exhaled nitric oxide (FeNO) measurements become an important adjunct for the evaluation of asthma. In addition, the availability of portable devices makes it possible to measure FeNO more easily and frequently in the routine pediatric practice. Despite various confounding factors affecting its levels, FeNO can be applicable in diagnosing asthma, monitoring treatment response, evaluating asthma control, and predicting asthma exacerbations. Thus, although pulmonary function tests are the standard tools for objective measurements of asthmatic control, FeNO can broaden the way of asthma monitoring and supplement standard clinical asthma care guidelines.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제25권1호
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• pp.1-12
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• 2022

Inflammation plays an important role in the outcome of patients with cystic fibrosis (CF). It may develop due to cystic fibrosis transmembrane conductance regulator protein dysfunction, pancreatic insufficiency, or prolonged pulmonary infection. Fecal calprotectin (FC) has been used as a noninvasive method to detect inflammation. Therefore, the aim of the current meta-analysis was to investigate the relationship between FC and phenotype severity in patients with CF. In this study, searches were conducted in PubMed, Science Direct, Scopus, and Embase databases up to August 2021 using terms such as "cystic fibrosis," "intestine," "calprotectin," and "inflammation." Only articles published in English and human studies were selected. The primary outcome was the level of FC in patients with CF. The secondary outcome was the relationship between FC and clinical severity. Statistical analysis was performed using Comprehensive Meta-Analysis software. Of the initial 303 references, only six articles met the inclusion criteria. The mean (95% confidence interval [CI]) level of FC was 256.5 mg/dL (114.1-398.9). FC levels were significantly associated with pancreatic insufficiency (mean, 243.02; 95% CI, 74.3 to 411.6; p=0.005; I²=0), pulmonary function (r=-0.39; 95% CI, -0.58 to -0.15; p=0.002; I²=60%), body mass index (r=-0.514; 95% CI, 0.26 to 0.69; p<0.001; I²=0%), and Pseudomonas colonization (mean, 174.77; 95% CI, 12.5 to 337.02; p=0.035; I²=71%). While FC is a reliable noninvasive marker for detecting gastrointestinal inflammation, it is also correlated with the severity of the disease in patients with CF.