• 한국자기공명학회논문지
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• 제22권4호
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• pp.82-90
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• 2018

The term "hangover" refers to symptoms such as headache, heartburn, nausea, and dizziness caused by acetaldehyde created through alcohol decomposition in the body after alcohol intake. Many scientists have conducted research on diverse drugs, foods, and medicinal herbs aimed at eliminating hangovers. However, research on metabolism to objectively verify or measure their effects on hangover symptoms has been lacking. Accordingly, in this study, deep sea water minerals were administered orally at varying concentrations to rats that consumed alcohol, and changes in the levels of amino acids in their bodies were measured using nuclear magnetic resonance spectroscopy to gauge the minerals' effects on hangover symptoms. Thus far, biochemical research on hangover cures has been confined to basic research measuring changes in the levels of alcohol dehydrogenase and acetaldehyde dehydrogenase as well as in the concentrations of ethanol, acetaldehyde, and acetate using spectroscopes such as enzyme-linked immunosorbent assay kits or gas chromatography-mass spectrometers. In comparison, this study presents pharmacokinetic research that simultaneously tracked biomaterials including amino acids and organic acids, metabolites associated with hangover, to clarify hangover mechanisms more specifically. In addition, this study examined hangover mechanisms without an external supply of tracked materials not overlapping with alcohol metabolism-related materials, such as external amino acids and sugars.

• 한국자기공명학회논문지
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• 제4권1호
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• pp.41-49
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• 2000

To design more efficient peptide antagonist against the HBV, preSl(21-47) which carries the HBV receptor binding site for hepatocytes was synthesized and the solution structure of preSl(21-47) was investigated using CD spectroscopy and NMR spectroscopy in membrane-mimicking environments. According to CD spectra, preSl(21-47) has a random structure in aqueous solution, while conformational change was induced by addition of TFE and SDS micelle. Tertiary structures as determined by NMR spectroscopy shows that preSl(21-47) has a very flexible structure even in SDS micelle.

• 한국자기공명학회논문지
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• 제5권1호
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• pp.37-45
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• 2001

Synthetic pulmonary surfactants consisting of a mixture of phospholipids with synthetic peptides based on human surfactant-associated protein SP-B were prepared. These surfactants were analyzed f3r their secondary structures by circular dichroism (CD) spectroscopy and NMR spectroscopy. Two synthetic peptides (SP-B(3), SP-B(4)) combined with the phospholipid mixture displayed significant surfactant properties. The CD spectra showed that the u-helical propensities of the peptides in DPC micelles. In the NMR spectroscopy, the tertiary structures of SP-B(3) show that it has $\alpha$-helical structure from Gln5 to Arg13 in DPC micelle and SP-B(4) show that they have $\alpha$-helical structure from Gln5 to Leu12 in DPC micelle. Based on these structures, truncated peptides originated from SP-B protein, can be designed as effective synthetic surfactants for clinical use.

• 한국자기공명학회논문지
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• 제24권3호
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• pp.70-76
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• 2020

The CRISPR-Cas system provides an adaptive immunity for bacteria and archaea against invading phages or foreign plasmids. In the type II CRISPR-Cas system, a single effector protein Cas9 and a guide RNA form an RNA-guided endonuclease complex that can degrade DNA targets of foreign origin. To avoid the Cas9-mediated destruction, phages evolved anti-CRISPR (Acr) proteins that neutralize the host bacterial immunity by inactivating the CRISPR-Cas system. Here we report the backbone ¹H, ¹⁵N, and ¹³C resonance assignments of AcrIIA5 that inhibits the endonuclease activity of type II-A Streptococcus thermophilus Cas9 and also Streptococcus pyogenesis Cas9 using triple resonance nuclear magnetic resonance spectroscopy. The backbone chemical shifts of AcrIIA5 predict a disordered region at the N-terminus, followed by an αββββαβββ fold.

• Journal of Korean Neurosurgical Society
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• 제51권5호
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• pp.312-315
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• 2012

We report magnetic resonance image (MRI) and magnetic resonance spectroscopy (MRS) findings in a patient of cerebral fat embolism (CFE) occurred in a 26-year-old woman after an autologous fat injection into the face. After initial neurologic symptom onset, MRI and MRS data were obtained two times to investigate repeated CFE. We obtained the MRS data in the two different time intervals and two different echo times to compare the lesions with normal brain parenchyma. The results of MRS data showed that a decrease in N-acetyl-aspartate, an increase in lactate and a very high early peak of free lipids between 0.9 and 1.4 ppm were obtained at the acute infarcted lesion as compared with normal brain parenchyma. In addition, these findings were more clearly detected on short echo time spectrum rather than long spectrum. A close relationship between the clinical manifestations and MRI and MRS findings of the brain can helpful to distinguish CFE with other conditions and to evaluate the cause materials of infarctions rather than conventional MRI or diffusion-weighted imaging.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.54-68
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• 2011

$^1H$ nuclear magnetic resonance (NMR) spectroscopy of biological samples has been proven to be an effective and nondestructive approach to probe drug toxicity within an organism. In this study, ketoprofen toxicity was investigated using $^1H$-NMR spectroscopy coupled with multivariate statistical analysis. Histopathologic test of ketoprofen-induced acute gastrointestinal damage in rats demonstrated a significant dose-dependent effect. Furthermore, principal component analysis (PCA) derived from $^1H$-NMR spectra of urinary samples showed clear separation between the vehicle-treated control and ketoprofen-treated groups. Moreover, PCA derived from endogenous metabolite concentrations through targeted profiling revealed a dose-dependent metabolic shift between the vehicle-treated control, low-dose ketoprofen-treated (10 mg/kg body weight), and high-dose ketoprofen-treated (50 mg/kg) groups coinciding with their gastric damage scores after ketoprofen administration. The resultant metabolic profiles demonstrated that the ketoprofen-induced gastric damage exhibited energy metabolism perturbations that increased urinary levels of citrate, cis-aconitate, succinate, and phosphocreatine. In addition, ketoprofen administration induced an enhancement of xenobiotic activity in fatty oxidation, which caused increase levels of N-isovalerylglycine, adipate, phenylacetylglycine, dimethylamine, betaine, hippurate, 3-indoxylsulfate, N,N-dimethylglycine, trimethyl-N-oxide, and glycine. These findings demonstrate that $^1H$-NMR-based urinary metabolic profiling can be used for noninvasive and rapid way to diagnose adverse drug effects and is suitable for explaining the possible biological pathways perturbed by nonsteroidal anti-inflammatory drug toxicity.

• 한국자기공명학회논문지
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• 제22권2호
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• pp.34-39
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• 2018

The Nuclear Magnetic Resonance (NMR) technique using Dynamic Nuclear Polarization (DNP) procedures is one of the promising techniques that enable overcoming low sensitivity problems in NMR spectroscopy. We constructed an ODNP-NMR system using a commercial benchtop EPR spectrometer. The $^1H$ NMR peak area of water in aqueous solutions of 4-hydroxy-TEMPO was enhanced more than 95 times in the ODNP-NMR experiments. Our signal enhancement results were about 55% of the previously reported result. This could be due to non-uniform microwave power over a sample and unwanted sample heating by microwave. However, this portable ODNP-NMR spectrometer will be eventually useful for site-specific detection with nano-scale spatial resolutions and molecular dynamics studies with significantly improved signal sensitivity.

• 대한방사선기술학회지:방사선기술과학
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• 제39권2호
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• pp.143-148
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• 2016

본 연구에서는 MRS 정량적 분석 중 jMRUI AMARES방법의 관찰자의 의존적 원인 요소를 숙련자와 비숙련자의 측정을 통하여 파악하고 하였다. 실험용 10주령 수컷 쥐의 간 부분을 3T MRI 장치를 활용하여 point resolved spectroscopy 펄스시퀀스를 이용하여 자기공명분광 데이터를 획득하였다. 획득된 데이터는 기준 값으로 사용하기 위해서 LCModel software 이용하여 1.3 ppm의 메틸렌 양성자와 4.7 ppm의 물 분자 양성자의 정량 비를 계산하였다. 7명의 비숙련 관찰자는 jMRUI AMARES 방법으로 총 지질을 1, 2주 간격으로 측정한 후 측정된 값을 SPSS를 이용하여 interclass correlation coefficient를 시행하였다. 관찰자 사이 간 측정치의 일관성의 신뢰도 분석을 표현한 크논바 알파 계수는 0.1 미만으로 나타났다. 1주차 데이터 값과 2주차 데이터 값의 평균값은 $0.096{\pm}0.038$로 LCModel의 분석 값보다 0.048로 50% 높게 관찰되었다. jMRUI AMARES분석 방법이 LCModel과 동일한 결과를 얻기 위해서는 정확한 대사물질의 개요를 숙지하고 획득된 그래프의 형태를 잘 파악하여 잔존 대사물질를 최소화 하여야 한다.

• Investigative Magnetic Resonance Imaging
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• 제7권1호
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• pp.31-38
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• 2003

목적 : 실험적으로 토끼 대퇴부에 유발한 농양에서 연속적 추적검사를 통하여 MRS 스펙트럼의 특징과 항생제 치료에 따른 대사산물의 변화를 분석하고자 하였다. 대상 및 방법 : 토끼 10마리의 대퇴부에 흰쥐의 대변으로부터 추출한 용액을 주사하여서 농양을 유발시켰고, 대조군 5마리와 항생제 치료군 5마리로 나누어 4주 동안 1주 간격으로 MRI와 MRS로 추적 검사를 하였다 MRI에서는 농양의 모양과 크기를 분석하였으며, 기존 문헌을 참조하여 MRS에서 보이는 대사산물의 스펙트럼을 분류하였다. N-acetyl alanine을 외적기준으로, lipid를 내적기준으로 하여 각 대사산물을 정량 분석하였고, 정량화된 값들이 농양의 시기에 따라 대조군과 치료군 사이에 차이가 있는지를 분석하였다. 결과 : MRI에서 농양 10 예 모두는 낭성 종괴로 보였으며, 크기는 22-77 mm였다. MRS에서는 감염을 시사하는 acetate, succinate와 여러 종류의 아미노산 peak가 대조군, 치료군 모두에서 여러 가지 조합으로 검출되었다. 그 중 1.92 ppm의 acetate(70%)가 가장 흔하게 보였다. Lipid peak에 대한 acetate peak 비율과 외적기준의 peak에 대한 acetate peak 비율은 대조군에서는 시기에 따라 큰 변화가 없는 반면에 치료군에서는 감소하는 경향이 있었다. 결론 : MRS는 농양에서 감염을 시사하는 대사산물을 검출함으로써 진단에 도움을 줄 수 있을 뿐 아니라 acetate peak는 농양의 진행 및 항생제 치료에 의해 영향을 받아서 농양의 활동도 지표로서 유용한 가치가 있을 것으로 사료된다.

• 대한의용생체공학회:의공학회지
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• 제27권2호
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• pp.53-58
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• 2006

In this study, transverse relaxation time (T2) measurement and the evaluation of the characteristics of the spectral peak related to stomach tissue metabolites were performed using ex vivo proton magnetic resonance spectroscopic imaging (MRSI) at 1.5-T MRI/S instruments. Thirty-two gastric tissues resected from 12 patients during gastric cancer surgery, of which 19 were normal tissue and 13 were cancerous tissue, were used to measure the $T_2$ of the magnetic resonance spectroscopy (MRS) peaks. The volume of interest data results from the MRSI measurements were extracted from the proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and were statistically analyzed. MR spectra were acquired using the chemical shift imaging (CSI) point resolved spectroscopy (CSI-PRESS) technique with the parameters of pulse repetition time (TR) and echo times (TE) TR/(TE1,TE2)=1500 msec/(35 msec, 144 msec), matrix $size=24{\times}24$, NA=1, and voxel $size=2.2{\times}2.2{\times}4mm^3$. In conclusion, the measured $T_2$ of the metabolite peaks, such as choline (3.21ppm) and lipid (1.33ppm), were significantly decreased (p<0.01 and p<0.05, respectively) in the cancerous stomach tissue.