• Clinical and Experimental Pediatrics
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• v.56 no.2
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• pp.45-51
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• 2013

Because nonalcoholic steatohepatitis can progress towards cirrhosis even in children, early detection of hepatic fibrosis and accurate diagnosis of nonalcoholic fatty liver disease (NAFLD) are important. Although liver biopsy is regarded as the gold standard of diagnosis, its clinical application is somewhat limited in children due to its invasiveness. Noninvasive diagnostic methods, including imaging studies, biomarkers of inflammation, oxidative stress, hepatic apoptosis, hepatic fibrosis, and noninvasive hepatic fibrosis scores have recently been developed for diagnosing the spectrum of NAFLD, particularly the severity of hepatic fibrosis. Although data and validation are still lacking for these noninvasive modalities in the pediatric population, these methods may be applicable for pediatric NAFLD. Therefore, noninvasive imaging studies, biomarkers, and hepatic fibrosis scoring systems may be useful in the detection of hepatic steatosis and the prediction of hepatic fibrosis, even in children with NAFLD.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.253-256
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• 1995

Polymers have been one of the emerging biomedical materials in the area of biomedical research which are applicable to the human body. For human applications, noninvasive characterization of the biomedical polymers has been one of the important topics, and is valuable information. Among others, the swelling rate is one of the important measurements needed for the hydrophilic polymers. NMR imaging has been a suitable method for the noninvasive study of such a material since it is sensitive to many physical and biochemical changes of the specimens. In addition, NMR techniques possess many useful intrinsic properties such as the relaxation and diffusion effects. The present study has provided a noble and noninvasive method of measuring the process of swelling as well as volumetric changes occurred in polymers and drug delivery processes in a drug delivery system (DDS) together with changes of released drug. This gives information, relating with both water ingress process, volumetric changes of polymer specimens and the visualization of sequential drug delivery process. Also, this study provides more reliable method to ascertain the time dependent swelling process compared to the conventional method. The important aspects is that the proposed method is truly noninvasive and is able to ascertain time dependent processes.

• Journal of Genetic Medicine
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• v.12 no.2
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• pp.72-78
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• 2015

Recently, noninvasive prenatal test (NIPT) has been adopted as a primary screening tool for fetal chromosomal aneuploidy. The principle of NIPT lies in isolating the fetal fraction of cell-free DNA in maternal plasma and analyzing it with bioinformatic tools to measure the amount of gene from the target chromosome, such as chromosomes 21, 18, and 13. NIPT will contribute to decreasing the need for unnecessary invasive procedures, including amniocentesis and chorionic villi sampling, for confirming fetal aneuploidy because of its higher positive predictive value than that of the conventional prenatal screening method. However, its greater cost than that of the current antenatal screening protocol may be an obstacle to the adoption of this innovative technique in clinical practice. Digital polymerase chain reaction (dPCR) is a novel approach for detecting and quantifying nucleic acid. dPCR provides real-time diagnostic advantages with higher sensitivity, accuracy, and absolute quantification than conventional quantitative PCR. Since the groundbreaking discovery that fetal cell-free nucleic acid exists in maternal plasma was reported, dPCR has been used for the quantification of fetal DNA and for screening for fetal aneuploidy. It has been suggested that dPCR will decrease the cost by targeting specific sequences in the target chromosome, and dPCR-based noninvasive testing will facilitate progress toward the implementation of a noninvasive approach for screening for trisomy 21, 18, and 13. In this review, we highlight the principle of dPCR and discuss its future implications in clinical practice.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.126-126
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• 2009

Noninvasive plasma diagnostic technique is introduced to analyze and characterize HICP (Helmholtz Inductively Coupled Plasma) source during the plasma etching process. The HICP reactor generates plasma mainly through RF source power at 13.56MHz RF power and RF bias power of 12.56MHz is applied to the cathode to independently control ion density and ion energy. For noninvasive sensors, the RF sensor and the OES (Optical emission spectroscopy) were employed since it is possible to obtain both physical and chemical properties of the reactor with plasma etching. The plasma impedance and optical spectra were observed while altering process parameters such as pressure, gas flow, source and bias power during the poly silicon etching process. In this experiment, we have found that data measured from these noninvasive sensors can be correlated to etch results. In this paper, we discuss the relationship between process parameters and the measurement data from RF sensor and OES such as plasma impedance and optical spectra and using these relationships to analyze and characterize H-ICP source.

• Journal of Genetic Medicine
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• v.18 no.2
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• pp.117-120
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• 2021

We experienced a case of Xq deletion -- 46,X,del(X)(q22.3) -- detected by abnormal noninvasive prenatal screening, subsequently diagnosed by amniocentesis. Genetic counseling was a challenge because there are few reports of prenatal diagnosis of Xq deletion. In each female cell, one X chromosome is inactivated at random early in development, and there may be a preferential inactivation of the abnormal X chromosome. But some proportions of genes escape inactivation. The most common manifestation in women with Xq deletion is primary or secondary ovarian failure. Critical regions for ovarian function may be located at the long arm of the X chromosome. But, the onset and the severity of ovarian failure may vary with diverse, intricate factors. We anticipate that noninvasive prenatal screening can identify the broader range of chromosomal or genetic abnormalities with the advances in technology and analytic methods. We report our case with a brief review of the literature.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.28 no.3
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• pp.61-68
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• 2022

Background: This study aimed to investigate the effects of noninvasive electrical stimulation combined with trunk stabilization exercise on balance and fall risk in patients with stroke. Methods: Twenty-two patients with stroke were enrolled in the study and randomly divided into experimental and control groups, each with 11 patients. noninvasive electrical stimulation combined with trunk stabilization training was applied to the experimental group, and sham noninvasive electrical stimulation combined with trunk stabilization training, to the control group. Both groups were treated for 6 weeks, five times a week for 30 min each time; the balance and fall risk of patients with stroke were measured before and after treatment, and the changes in the two groups were compared and analyzed. Results: The experimental group's left and right weight-bearing indices (affect and non-affect sides) and the front and rear weight-bearing indices, were significantly improved (p<.05, p<.001). when the changes in balance ability between groups were compared before and after treatment. The total fall efficacy score in the experimental group was substantially lower than that in the control group when the changes in fall efficacy score were compared between groups following treatment (p<.001). Conclusion: The improvement in balance and fall risk in patients with stroke can be attributed to using noninvasive electrical stimulation in combination with trunk stabilization training. This clinically helpful treatment method for patients with stroke warrants further promotion and implementation in the clinic.

• Journal of Biomedical Engineering Research
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• v.16 no.2
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• pp.167-174
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• 1995

Development of a noninvasive intensive care system calls for the use of evoked potentials (EPs) as a means of diagnosing traumatic head-injured patients. The experiment entails surgically placing two subarachnoid bolts and a subdural balloon through the skull to simulate a subdural hematoma. Using various levels of intracranial pressure (ICP) and/or different sizes of balloons, auditory evoked potentials (AEPs) were recorded from a rabbit. Six positive peak latencies ($P_1 - P_6$) and five negative peak latencies ($N_l- N_5$) were extracted from an averaged AEP waveform. Multiple regression analyses were performed for determining. a relationship between the ICP and AEP peak latencies. The results indicate that a major correlation of ch, mges on AEP peak latencies is due to mechanical forces of a mass (inflated balloon simulating a hematoma) in the distortion of the brain matter rather than increased ICP itself.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.762-766
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• 1998

Mechanical valve is one of the most widely used implantable artificial organs, Since its failure (mechanical failures and thrombosis to name two representative example) means the death of patient, its reliability is very important and early noninvasive detection is essential requirement . This paper will explain the method to detect the thrombosis formation by spectral analysis and neural network. In order quantitatively to distinguish peak of a normal valve from that of a thrombotic valve, a 3 layer backpropagation neural network, which contains 7,000 input nodes, 20 hidden layer and 1output , was employed. The trained neural network can distinguish normal and thrombotic valve with a probability that is higher than 90% . In conclusion, the acoustical spectrum analysis coupled with a neural network algorithm lent itself to the noninvasive monitoring of implanted mechanical valves. This method will be applied to be applied to the performance evaluation of other implantable rtificial organs.

• Journal of Biomedical Engineering Research
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• v.33 no.3
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• pp.114-127
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• 2012

Recent technical advancement allows noninvasive measurement of blood glucose. In this literature, we reviewed various noninvasive techniques for measuring glucose concentration. Optical or electrical methods have been investigated. Optical techniques include near-infrared spectroscopy, Raman spectroscopy, optical coherence technique, polarization, fluorescence, occlusion spectroscopy, and photoacoustic spectroscopy. Electrical methods include reverse iontophoresis, impedance spectroscopy, and electromagnetic sensing. Ultrasound, detection from breath, or fluid harvesting technique can be used to measure blood glucose level. Combination of various methods is also promising. Although there are many interesting and promising technologies and devices, there need further researches until a commercially available non-invasive glucometer is popular.

• Journal of Genetic Medicine
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• v.12 no.2
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• pp.61-65
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• 2015

Whole genome sequencing (WGS)-based noninvasive prenatal test (NIPT) is the first method applied in the clinical setting out of various NIPT techniques. Several companies, such as Sequenom, BGI, and Illumina offer WGS-based NIPT, each with different technical and bioinformatic approaches. Sequenom, BGI, and Illumina utilize z-, t-, and L-scores, as well as normalized chromosome values, respectively, for trisomy detection. Their outstanding performance has been demonstrated in clinical studies of more than 100,000 pregnancies. The sensitivity and specificity for detection of trisomies 13, 18, and 21 were above 98%, as reported by all three companies. Unlike other techniques, WGS-based NIPT can detect other trisomies as well as clinically significant segmental duplications/deletions within a chromosome, which could expand the scope of NIPT. Incorrect results could be due to low fetal fraction, fetoplacental mosaicism, confined placental mosaicism or maternal copy number variation (CNV). Among those, maternal CNV is a significant contributor of false positive results and therefore genome wide scanning plays an important role in preventing the occurrence of false positives. In this article, the bioinformatic techniques and clinical performance of three major companies are comprehensively reviewed.