• 대한소아치과학회지
• /
• 제45권3호
• /
• pp.354-362
• /
• 2018

Periogen은 실시간 PCR 방법을 이용한 우식활성 검사법으로, 치아우식 유발균에 대한 정량적인 분석을 통해 개개인의 치아우식 위험도를 평가한다. 이 연구는 소아에서 Periogen과 치아우식 경험 지수(dmft, dmft indices)와의 상관성을 평가하고, 기존의 치아우식 위험 검사법인 Cariview, 치아우식 평가 도구(Caries Assessment Tool)와 비교할 목적으로 시행되었다. 만 6세 미만 83명의 소아를 대상으로 실험이 진행되었다. 시진을 통해 치아우식 경험 지수(dmft, dmft indices)가 기록되었으며, 간단한 설문 조사를 통해 CAT 평가 시행되었다. Periogen, Cariview는 제조사의 지시에 따라 치아우식 위험도 평가 시행되었다. 그 결과 Periogen, Cariview 그리고 CAT는 dmfts index와 상관계수가 각각 0.38, 0.56, 0.66을 보여 모두 중등도의 상관관계를 보였다(p < 0.01). Periogen, Cariview 그리고 CAT의 민감도와 특이도 분석의 경우, 민감도는 각각 43%, 76%, 95%를 보였으며, 특이도는 각각 80%, 72%, 74%를 보였다. ROC 곡선의 곡선하면적(AUC)는 각각 0.69, 0.81, 0.85를 보였다. Periogen의 경우 다른 기존의 두 가지 검사법에 비해 치아우식 위험도 평가에 있어 더 낮은 유효성을 보였다. 따라서 임상적으로 사용되기 위해서는 더 나은 유효성을 위한 개량이 필요할 것으로 보인다.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2012년도 자성 및 자성재료 국제학술대회
• /
• pp.104-105
• /
• 2012

The temperature dependence of the effective magnetic anisotropy constant K(T) of ferrite nanoparticles is obtained based on the measurements of SQUID magnetometry. For this end, a very simple but intuitive and direct method for determining the temperature dependence of anisotropy constant K(T) in nanoparticles is introduced in this study. The anisotropy constant at a given temperature is determined by associating the particle size distribution f(r) with the anisotropy energy barrier distribution $f_A(T)$. In order to estimate the particle size distribution f(r), the first quadrant part of the hysteresis loop is fitted to the classical Langevin function weight-averaged with the log?normal distribution, slightly modified from the original Chantrell's distribution function. In order to get an anisotropy energy barrier distribution $f_A(T)$, the temperature dependence of magnetization decay $M_{TD}$ of the sample is measured. For this measurement, the sample is cooled from room temperature to 5 K in a magnetic field of 100 G. Then the applied field is turned off and the remanent magnetization is measured on stepwise increasing the temperature. And the energy barrier distribution $f_A(T)$ is obtained by differentiating the magnetization decay curve at any temperature. It decreases with increasing temperature and finally vanishes when all the particles in the sample are unblocked. As a next step, a relation between r and $T_B$ is determined from the particle size distribution f(r) and the anisotropy energy barrier distribution $f_A(T)$. Under the simple assumption that the superparamagnetic fraction of cumulative area in particle size distribution at a temperature is equal to the fraction of anisotropy energy barrier overcome at that temperature in the anisotropy energy barrier distribution, we can get a relation between r and $T_B$, from which the temperature dependence of the magnetic anisotropy constant was determined, as is represented in the inset of Fig. 1. Substituting the values of r and $T_B$ into the $N{\acute{e}}el$-Arrhenius equation with the attempt time fixed to $10^{-9}s$ and measuring time being 100 s which is suitable for conventional magnetic measurement, the anisotropy constant K(T) is estimated as a function of temperature (Fig. 1). As an example, the resultant effective magnetic anisotropy constant K(T) of manganese ferrite decreases with increasing temperature from $8.5{\times}10^4J/m^3$ at 5 K to $0.35{\times}10^4J/m^3$ at 125 K. The reported value for K in the literatures is $0.25{\times}10^4J/m^3$. The anisotropy constant at low temperature region is far more than one order of magnitude larger than that at 125 K, indicative of the effects of inter?particle interaction, which is more pronounced for smaller particles.

• 한국응용과학기술학회지
• /
• 제37권1호
• /
• pp.91-101
• /
• 2020

이 연구는 비만이 심장 조직에서 자가포식 관련 단백질 발현에 미치는 영향을 확인하기 위해 고지방 식이(20주)를 통해 비만을 유도한 후 8주간의 트레드밀 운동을 실시하고, 자가포식의 유도, 형성 그리고 자가포식포와 라이소좀 융합단계를 조절하는 단백질의 발현을 확인하였다. 실험동물(SD rat)은 20주간의 고지방식이(탄수화물: 20%, 지방: 60%, 단백질: 20%)를 통해 비만을 유도하였으며, 8주간의 트레드밀 운동(주 5일, 하루 30분, 5분; 8m/min, 5분; 11m/min, 20분; 14m/min)을 실시하였다. 집단 구분은 정상식이 비교군(n=10), 고지방식이 비교군(n=10), 고지방식이 운동군(n=10)으로 구분하였다. 8주간의 트레드밀 운동 실시 전과 후에 경구당부하검사를 실시하여 곡선 하 면적(area under the curve; AUC)을 산출하였으며, 공복시 인슐린 농도와 포도당 농도를 통해 인슐린 저항성 지표인 HOMA-IR과 체중 당 복부지방량(abdominal visceral fat/Body weight; AVF/BW)를 산출하여 비교하였다. 또한 심장 조직에서 자가포식 관련 단백질을 분석하여 운동 트레이닝의 효과를 검증하였다. 장기간의 고지방식이를 통해 HFD-CON 그룹에서는 비만이 유도되었으며, ND-CON 그룹에 비해 체중, AUC, HOMA-IR, AVF/BW가 증가되는 것으로 나타났다. 하지만 8주간의 트레드밀 운동을 실시한 HFD-TE 그룹에서는 AUC, HOMA-IR, AVF/BW가 개선되는 것으로 나타났다. 체중의 경우, 감소되는 경향은 있었지만, 통계적으로 유의한 차이는 없었다. 자가포식 유도에 관여하는 mTOR와 AMPK는 비만상황에서 모두 감소되었지만, 운동을 통해 증가되는 것으로 나타났다. 자가포식 형성에 관련된 Beclin-1, BNIP3, ATG-7, p62, LC3는 비만상황에서 모두 증가하는 것으로 나타났으며, 운동을 통해 감소되는 것으로 나타났다. 자기포식포와 라이소좀 융합단계 조절하는 Cathepsin L과 LAMP2는 비만상황에서 모두 감소되었으며, 운동을 통해 증가하는 것으로 나타났다. 트레드밀 운동과 같은 신체활동은 대사성 질환에서 나타나는 병리학적 현상을 개선하고 자가포식 과정을 정상적으로 유도하는 것으로 나타났다. 따라서 트레드밀 운동이 심장 관련 질환의 예방 및 치료에 있어 일차적으로 고려해야할 필요성이 있다고 제안한다.

• Korean Journal of Radiology
• /
• 제22권6호
• /
• pp.959-969
• /
• 2021

Objective: This study aimed to evaluate the role of preoperative two-dimensional (2D) shear wave elastography (SWE) in assessing the stages of liver fibrosis in patients with suspected biliary atresia (BA) and compared its diagnostic performance with those of serum fibrosis biomarkers. Materials and Methods: This study was approved by the ethical committee, and written informed parental consent was obtained. Two hundred and sixteen patients were prospectively enrolled between January 2012 and October 2018. The 2D SWE measurements of 69 patients have been previously reported. 2D SWE measurements, serum fibrosis biomarkers, including fibrotic markers and biochemical test results, and liver histology parameters were obtained. 2D SWE values, serum biomarkers including, aspartate aminotransferase to platelet ratio index (APRi), and other serum fibrotic markers were correlated with the stages of liver fibrosis by METAVIR. Receiver operating characteristic (ROC) curves and area under the ROC (AUROC) curve analyses were used. Results: The correlation coefficient of 2D SWE value in correlation with the stages of liver fibrosis was 0.789 (p < 0.001). The cut-off values of 2D SWE were calculated as 9.1 kPa for F1, 11.6 kPa for F2, 13.0 kPa for F3, and 15.7 kPa for F4. The AUROCs of 2D SWE in the determination of the stages of liver fibrosis ranged from 0.869 to 0.941. The sensitivity and negative predictive value of 2D SWE in the diagnosis of ≥ F3 was 93.4% and 96.0%, respectively. The diagnostic performance of 2D SWE was superior to that of APRi and other serum fibrotic markers in predicting severe fibrosis and cirrhosis (all p < 0.005) and other serum biomarkers. Multivariate analysis showed that the 2D SWE value was the only statistically significant parameter for predicting liver fibrosis. Conclusion: 2D SWE is a more effective non-invasive tool for predicting the stage of liver fibrosis in patients with suspected BA, compared with serum fibrosis biomarkers.

• 한국식품영양학회지
• /
• 제22권4호
• /
• pp.625-632
• /
• 2009

This study determined the effects of added buckwheat extract on the rate of corn starch hydrolysis in vitro as well as blood glucose responses through its supplementation in healthy subjects. The rate of corn starch hydrolysis in the presence or absence of various buckwheat extracts was determined in an in vitro enzyme/dialysis system for 2 hr. The buckwheat was extracted by water, ethanol(40%, 70%, 100%) and methanol(40%, 70%, 100%), respectively. Twenty percent(w/w) additions of the ethanol, methanol and water buckwheat extract to corn starch solution significantly reduced the starch hydrolysis at every minute for 2 hr(p<0.05). The calculated hydrolysis indices of the buckwheat extracts were in the order of 100% ethanol extract(50), 100% methanol(54), 40% ethanol(58), 40% methanol(62), 70% methanol(64), 70% ethanol(68), water (82). For the blood glucose response study, groups of 12 volunteers were given 50 g of boiled rice with or without buckwheat extract(10% and 20% of starch weight) using the 100%, 70%, and 40% ethanol extracts, respectively. The addition of each buckwheat ethanol extract significantly reduced blood glucose concentrations at three or more points during 2 hr and also reduced the mean peak rise and area under the blood glucose curve(p<0.05). The calculated glycemic index(GI) values for all ethanol buckwheat extract groups were significantly decreased compared to the control(rice). At the concentrations of 20%, the buckwheat 100% ethanol extracts lowered the GI by 68%. The 100% ethanol extract was more effective than the 70% and 40% extracts for reducing GI. Therefore, the 100% ethanol buckwheat extract would be the most therapeutically useful in modifying postprandial hyperglycemia.

• Journal of Korean Neurosurgical Society
• /
• 제64권4호
• /
• pp.575-584
• /
• 2021

Objective : Cervical expansive laminoplasty is an effective surgical method to address multilevel cervical spinal stenosis. During surgery, the spinous processes of C2 and C7 are usually preserved to keep the insertion points of the cervical musculature and nuchal ligament intact. In this regard, dome-like laminectomy (undercutting of C7 lamina) instead of laminoplasty is performed on C7 in selected cases. However, resection of the lamina can weaken the C7 lamina, and stress fractures may occur, but this complication has not been characterized in the literature. The objective of the present study was to investigate the incidence and risk factors for C7 laminar fracture after C7 dome-like laminectomy and its impact on clinical and radiological outcomes. Methods : Patients who underwent cervical open-door laminoplasty combined with C7 dome-like laminectomy (n=123) were classified according to the presence of C7 laminar fracture. Clinical parameters (neck/arm pain score and neck disability index) and radiologic parameters (C2-7 angle, C2-7 sagittal vertical axis, and C7-T1 angle) were compared between the groups preoperatively and at postoperatively at 3, 6, 12, and 24 months. Risk factors for complications were evaluated, and a formula estimating C7 fracture risk was suggested. Results : C7 lamina fracture occurred in 32/123 (26%) patients and occurred at the bilateral isthmus in 29 patients and at the spinolaminar junction in three patients. All fractures appeared on X-ray within 3 months postoperatively, but patients did not present any neurological deterioration. The fracture spontaneously healed in 27/32 (84%) patients at 1 year and in 29/32 (91%) at 2 years. During follow-up, clinical outcomes were not significantly different between the groups. However, patients with C7 fractures showed a more lordotic C2-7 angle and kyphotic C7-T1 angle than patients without C7 fractures. C7 fracture was significantly associated with the extent of bone removal. By incorporating significant factors, the probability of C7 laminar fracture could be assessed with the formula 'Risk score = 1.08 × depth (%) + 1.03 × length (%, of the posterior height of C7 vertebral body)', and a cut-off value of 167.9% demonstrated a sensitivity of 90.3% and a specificity of 65.1% (area under the curve, 0.81). Conclusion : C7 laminar fracture can occur after C7 dome-like laminectomy when a substantial amount of lamina is resected. Although C7 fractures may not cause deleterious clinical outcomes, they can lead to an unharmonized cervical curvature. The chance of C7 fracture should be discussed in the shared decision-making process.

• Journal of Nutrition and Health
• /
• 제44권4호
• /
• pp.275-283
• /
• 2011

본 실험은 주요 phytoestrogen에 속하는 genistein, coumestrol, enterolactone의 식이보충이 제2형 당뇨동물모델에서 당질대사 개선에 미치는 효과를 알아보고자 C57BL/KsOlaHsd-db/db 마우스를 이용하여 내당능, 당화헤모글로빈 농도, 당대사 관련 효소활성, 조직 중 글리코겐과 최종당화산물 수준 등을 측정하였다. 그 결과, phytoestrogen의 보충(3.75 mg/100 g diet)이 당뇨동물의 체중변화, 식이 및 수분 섭취량 그리고 장기무게에는 유의적인 영향을 미치지 않았으나, 모든 phytoestrogen의 보충은 당뇨동물의 공복 혈당, 경구 내당능 검사 시 혈당반응곡선 아래면적 및 혈중 HbA1c 수준을 유의적으로 낮추었다. 또한 모든 phytoestrogen의 보충은 당뇨동물의 혈장 글루카곤 수준을 유의적으로 낮추었으며, coumestrol과 enterolactone의 보충은 간 조직 중 글리코겐 수준을 유의적으로 증가시켰다. 이상의 결과들은 genistein, coumestrol, enterolactone의 3종 phytoestrogen의 식이보충이 제2형 당뇨동물에서 내당능을 개선시킬 수 있음을 시사하였으나 그 기전에 대해서는 향후 추가 연구가 필요하다고 본다.

• Journal of Dental Anesthesia and Pain Medicine
• /
• 제22권2호
• /
• pp.145-153
• /
• 2022

Background: Postoperative analgesia (POA) is an important determinant of successful treatment. Dexmedetomidine (DEX) has recently gained attention as a promising adjuvant to local anesthetics (LA). The present study aimed to evaluate the efficacy and safety of levobupivacaine (LB) as an adjuvant during inferior alveolar nerve block (IANB) in the extraction of lower impacted third molars (LITM). Methods: A prospective, randomized, placebo-controlled, triple-blind, parallel-arm, and clinical study was performed on 50 systemically healthy participants who required removal of an asymptomatic LITM. Using a 1:1 distribution, the participants were randomized into two groups (n = 25). Group L (control group) received 1.8 mL of 0.5% LB and 0.2 mL normal saline (placebo) and Group D (study group) received a blend of 1.8 mL of 0.5% LB and 0.2 mL (20 ㎍) DEX. The primary outcome variable was the duration of POA and hemodynamic stability, and the secondary variable was the total number of analgesics required postoperatively for up to 72 h. The participants were requested to record the time of rescue analgesic use and the total number of rescue analgesics taken. The area under the curve was plotted for the total number of analgesics administered. The pain was evaluated using the visual analog scale. Data analysis was performed using paired students and unpaired t-test, Mann-Whitney U test, Chi-square test, and receiver operating characteristic analysis. Statistical significance was set at P < 0.05. Results: The latency, profoundness of anesthesia, and duration of POA were statistically significant (P < 0.05). The differences between mean pain scores at 6, 12, 24, 48, and 72 h were found to be significant (each P = 0.0001). Fewer analgesics were required by participants in group D (2.12 ± 0.33) than in L (4.04 ± 0.67), with a significant difference (P = 0.0001). Conclusion: Perineurally administered LA with DEX is a safe, effective, and therapeutic approach for improving latency, providing profound POA, and reducing the need for postoperative analgesia.

• Nutrition Research and Practice
• /
• 제10권1호
• /
• pp.11-18
• /
• 2016

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. $\small{D}$-xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of $\small{D}$-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with $\small{D}$-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with $\small{D}$-xylose. These groups were maintained for two weeks. The effects of $\small{D}$-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ${\beta}$-cells were analyzed. RESULTS: In vivo, $\small{D}$-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. $\small{D}$-xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of $\small{D}$-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with $\small{D}$-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, $\small{D}$-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, $\small{D}$-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ${\beta}$-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

• Korean Journal of Radiology
• /
• 제21권7호
• /
• pp.859-868
• /
• 2020

Objective: To investigate the value of initial CT quantitative analysis of ground-glass opacity (GGO), consolidation, and total lesion volume and its relationship with clinical features for assessing the severity of coronavirus disease 2019 (COVID-19). Materials and Methods: A total of 84 patients with COVID-19 were retrospectively reviewed from January 23, 2020 to February 19, 2020. Patients were divided into two groups: severe group (n = 23) and non-severe group (n = 61). Clinical symptoms, laboratory data, and CT findings on admission were analyzed. CT quantitative parameters, including GGO, consolidation, total lesion score, percentage GGO, and percentage consolidation (both relative to total lesion volume) were calculated. Relationships between the CT findings and laboratory data were estimated. Finally, a discrimination model was established to assess the severity of COVID-19. Results: Patients in the severe group had higher baseline neutrophil percentage, increased high-sensitivity C-reactive protein (hs-CRP) and procalcitonin levels, and lower baseline lymphocyte count and lymphocyte percentage (p < 0.001). The severe group also had higher GGO score (p < 0.001), consolidation score (p < 0.001), total lesion score (p < 0.001), and percentage consolidation (p = 0.002), but had a lower percentage GGO (p = 0.008). These CT quantitative parameters were significantly correlated with laboratory inflammatory marker levels, including neutrophil percentage, lymphocyte count, lymphocyte percentage, hs-CRP level, and procalcitonin level (p < 0.05). The total lesion score demonstrated the best performance when the data cut-off was 8.2%. Furthermore, the area under the curve, sensitivity, and specificity were 93.8% (confidence interval [CI]: 86.8-100%), 91.3% (CI: 69.6-100%), and 91.8% (CI: 23.0-98.4%), respectively. Conclusion: CT quantitative parameters showed strong correlations with laboratory inflammatory markers, suggesting that CT quantitative analysis might be an effective and important method for assessing the severity of COVID-19, and may provide additional guidance for planning clinical treatment strategies.