• Journal of Genetic Medicine
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• 제12권2호
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• pp.66-71
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• 2015

Down syndrome screening with cell-free DNA (cfDNA) in the maternal plasma has recently received much attention in the prenatal diagnostic field. Indeed, a large amount of evidence has already accumulated to show that screening tests with cfDNA are more sensitive and specific than conventional maternal serum and/or ultrasound screening. Globally, more than 1,000,000 of these noninvasive prenatal tests (NIPTs) have been performed to date. There are several different methods for NIPTs that are currently commercially available, including shotgun massively parallel sequencing, targeted massively parallel sequencing, and single nucleotide polymorphism (SNP)-based methods. All of these methods have their own advantages and disadvantages. In this review, I will focus specifically on the SNP-based NIPT.

• Clinical and Experimental Pediatrics
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• 제63권1호
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• pp.3-7
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• 2020

High-flow nasal cannula (HFNC) is a relatively safe and effective noninvasive ventilation method that was recently accepted as a treatment option for acute respiratory support before endotracheal intubation or invasive ventilation. The action mechanism of HFNC includes a decrease in nasopharyngeal resistance, washout of dead space, reduction in inflow of ambient air, and an increase in airway pressure. In preterm infants, HFNC can be used to prevent reintubation and initial noninvasive respiratory support after birth. In children, flow level adjustments are crucial considering their maximal efficacy and complications. Randomized controlled studies suggest that HFNC can be used in cases of moderate to severe bronchiolitis upon initial low-flow oxygen failure. HFNC can also reduce intubation and mechanical ventilation in children with respiratory failure. Several observational studies have shown that HFNC can be beneficial in acute asthma and other respiratory distress. Multicenter randomized studies are warranted to determine the feasibility and adherence of HFNC and continuous positive airway pressure in pediatric intensive care units. The development of clinical guidelines for HFNC, including flow settings, indications, and contraindications, device management, efficacy identification, and safety issues are needed, particularly in children.

• Journal of Genetic Medicine
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• 제14권1호
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• pp.31-33
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• 2017

Chromosomal loss in trisomy (trisomy rescue) to generate a disomic fetus can cause confined placental mosaicism and/or feto/placental mosaicism. After trisomy rescue event, there is a risk of fetal uniparental disomy (UPD). Noninvasive prenatal test (NIPT) reflects the genomic constitution of the placenta, not of the fetus itself. Feto-placental discrepancy can therefore cause false-positive (trisomy) NIPT results. These discordant NIPT results can serve as important clues to find UPD associated with confined placental mosaicism. We report a case with maternal UPD of chromosome 20, detected by NIPT of 1,000 high-risk pregnancies, carried out for detecting chromosomal abnormalities in Koreans.

• Neurospine
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• 제15권4호
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• pp.394-399
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• 2018

Subarachnoid pleural fistula (SPF) is an aberrant communication between the pleural cavity and subarachnoid space, resulting in uncontrolled cerebrospinal fluid drainage. The negative pressure of the pleural cavity creates a continuous suctioning effect, thereby impeding the spontaneous closure of these fistulas. Dural tears or punctures in cardiothoracic procedures, spinal operations, and trauma are known to cause such abnormal communications. Failure to recognize this entity may result in sudden neurological or respiratory complications. Hence, a high index of suspicion is required for early diagnosis and prompt management. Noninvasive positive pressure ventilation has been described to be effective in managing such fistulas, thus mitigating the high morbidity associated with exploratory surgery for primary repair. Herein, we describe the typical presentation of SPF and the clinical course, treatment, and follow-up of a patient who sustained SPF following anterior thoracic spinal surgery.

• Journal of Genetic Medicine
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• 제12권2호
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• pp.79-84
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• 2015

Purpose: We developed and validated a fetal trisomy detection method for use as a noninvasive prenatal test (NIPT) including a Clinical Laboratory Improvement Amendments (CLIA)-certified bioinformatics pipeline on a cloud-based computing system using both Illumina and Life Technology sequencing platforms for 221 Korean clinical samples. We determined the necessary proportions of the fetal fraction in the cell-free DNA (cfDNA) sample for NIPT of trisomies 13, 18, and 21 through a limit of quantification (LOQ) test. Materials and Methods: Next-generation sequencing libraries from 221 clinical samples and three positive controls were generated using Illumina and Life Technology chemistries. Sequencing results were uploaded to a cloud and mapped on the human reference genome (GRCh37/hg19) using bioinformatics tools. Based on Z-scores calculated by normalization of the mapped read counts, final aneuploidy reports were automatically generated for fetal aneuploidy determination. Results: We identified in total 29 aneuploid samples, and additional analytical methods performed to confirm the results showed that one of these was a false-positive. The LOQ test showed that the proportion of fetal fraction in the cfDNA sample would affect the interpretation of the aneuploidy results. Conclusion: Noninvasive chromosome examination (NICE), a CLIA-certified NIPT with a cloud-based bioinformatics platform, showed unambiguous success in fetus aneuploidy detection.

• 환경생물
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• 제26권3호
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• pp.264-269
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• 2008

본 연구는 비침습적 분변 샘플을 이용하여 기러기류의 유전분석이 가능한지 알아보고자 수행되었다. 또한 본 연구에서는 분변을 이용한 연구의 실험적 효율성을 높이는 방법이 요구되었다. 따라서 2007년 한국에서 월동하는 겨울 기러기류의 분변을 서로 다른 두 집단에서 채집하였고, 최종적으로 총 32개 분변 샘플이 분자유전학적 기법으로 분석되었다. 그 결과 총 14개의 haplotype이 나타났으며, 이는 쇠기러기 (Anser albifrons)와 큰기러기(Anser fabalis)그룹으로 분류되었다. 분변을 이용한 연구는 야생에 서식하고 있는 종에게 직접적인 위해를 가하지 않는 방법으로 큰 의미가 있다. 본 연구를 통하여 분변 샘플을 이용한 분자유전학적 실험의 효율성을 높일 수 있는 연구방법이 찾아졌으며, 또한 이 결과는 비침습적 분변 샘플을 이용한 우리나라 월동 기러기류의 첫 번째 연구로서 그 의의가 있다.

• Clinical and Experimental Pediatrics
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• 제60권9호
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• pp.273-281
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• 2017

To date, preterm infants with respiratory distress syndrome (RDS) after birth have been managed with a combination of endotracheal intubation, surfactant instillation, and mechanical ventilation. It is now recognized that noninvasive ventilation (NIV) such as nasal continuous positive airway pressure (CPAP) in preterm infants is a reasonable alternative to elective intubation after birth. Recently, a meta-analysis of large controlled trials comparing conventional methods and nasal CPAP suggested that CPAP decreased the risk of the combined outcome of bronchopulmonary dysplasia or death. Since then, the use of NIV as primary therapy for preterm infants has increased, but when and how to give exogenous surfactant remains unclear. Overcoming this problem, minimally invasive surfactant therapy (MIST) allows spontaneously breathing neonates to remain on CPAP in the first week after birth. MIST has included administration of exogenous surfactant by intrapharyngeal instillation, nebulization, a laryngeal mask, and a thin catheter. In recent clinical trials, surfactant delivery via a thin catheter was found to reduce the need for subsequent endotracheal intubation and mechanical ventilation, and improves short-term respiratory outcomes. There is also growing evidence for MIST as an alternative to the INSURE (intubation-surfactant-extubation) procedure in spontaneously breathing preterm infants with RDS. In conclusion, MIST is gentle, safe, feasible, and effective in preterm infants, and is widely used for surfactant administration with noninvasive respiratory support by neonatologists. However, further studies are needed to resolve uncertainties in the MIST method, including infant selection, optimal surfactant dosage and administration method, and need for sedation.

• 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.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.420-423
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• 1997

The oxygen saturation of blood can be measured by sensing the difference absorption in optical spectra of Hb and $HbO_2$, as the well known previous study. [1] In this study we developed the noninvasive tissue reflectance oximeter(TRO) using three kinds of LEDs which produce a peak spectral emission at a wavelength of 565, 660 and 940nm. And we tested the unction of the TR oximeter by comparing the output signals measured on normal tissue to measured on low oxygenated tissue. The results showed that oxygen saturation of blood and biological tissue can be monitored from the separation arrangement light source and detector.

• The Journal of the Acoustical Society of Korea
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• 제29권2E호
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• pp.55-63
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• 2010

High Intensity Focused Ultrasound (HIFU) is a noninvasive surgical method mainly targeting deeply located cancer tissue. Ultrasound is generated from an extemally located transducer and the beam is focused at the target volume, so that selective damage can be achieved without harm to overlying or surrounding tissues. The mechanism for cell killing can be combination of thermal and cavitational damage. Although cavitation can be an effective means of tissue destruction, the possibility of massive hemorrhage and the unpredictable nature of cavitational events prevent clinical application of cavitation. Hence, thermal damage has been a main focus related to HIFU research. 2D phased array transducer systems allow electronic scanning of focus, multi-foci, and anti-focus with multi-foci, so that HIFU becomes more applicable in clinical use. Currently, lack of noninvasive monitoring means of HIFU is the main factor to limit clinical applications, but development in MRI and Ultrasound Imaging techniques may be able to provide solutions to overcome this problem. With the development of advanced focusing algorithm and monitoring means, complete noninvasive surgery is expected to be implemented in the near future.