• The Korean Journal of Physiology and Pharmacology
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• 제23권3호
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• pp.203-217
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• 2019

The present study was designed to examine the effect of heme oxygenase-1 (HO-1) induction by cobalt protoporphyrin (CoPP) on the cardiac functions and morphology, electrocardiogram (ECG) changes, myocardial antioxidants (superoxide dismutase [SOD] and glutathione [GSH]), and expression of heat shock protein (Hsp) 70 and connexin 43 (Cx-43) in myocardial muscles in isoproterenol (ISO) induced myocardial infarction (MI). Thirty two adult male Sprague Dawely rats were divided into 4 groups (each 8 rats): normal control (NC) group, ISO group: received ISO at dose of 150 mg/kg body weight intraperitoneally (i.p.) for 2 successive days; ISO + Trizma group: received (ISO) and Trizma (solvent of CoPP) at dose of 5 mg/kg i.p. injection 2 days before injection of ISO, with ISO at day 0 and at day 2 after ISO injections; and ISO + CoPP group: received ISO and CoPP at a dose of 5 mg/kg dissolved in Trizma i.p. injection as Trizma. We found that, administration of ISO caused significant increase in heart rate, corrected QT interval, ST segment, cardiac enzymes (lactate dehydrogenase, creatine kinase-muscle/brain), cardiac HO-1, Hsp70 with significant attenuation in myocardial GSH, SOD, and Cx-43. On the other hand, administration of CoPP caused significant improvement in ECG parameters, cardiac enzymes, cardiac morphology; antioxidants induced by ISO with significant increase in HO-1, Cx-43, and Hsp70 expression in myocardium. In conclusions, we concluded that induction of HO-1 by CoPP ameliorates ISO-induced myocardial injury, which might be due to up-regulation of Hsp70 and gap junction protein (Cx-43).

• Endocrinology and Metabolism
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• 제33권4호
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• pp.485-492
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• 2018

Background: Increasing evidence supports interplay between aldosterone and parathyroid hormone (PTH), which may aggravate cardiovascular complications in various heart diseases. Negative structural cardiovascular remodeling by primary aldosteronism (PA) is also suspected to be associated with changes in calcium levels. However, to date, few clinical studies have examined how changes in calcium and PTH levels influence cardiovascular outcomes in PA patients. Therefore, we investigated the impact of altered calcium homeostasis caused by excessive aldosterone on cardiovascular parameters in patients with PA. Methods: Forty-two patients (mean age $48.8{\pm}10.9$ years; 1:1, male:female) whose plasma aldosterone concentration/plasma renin activity ratio was more than 30 were selected among those who had visited Severance Hospital from 2010 to 2014. All patients underwent adrenal venous sampling with complete access to both adrenal veins. Results: The prevalence of unilateral adrenal adenoma (54.8%) was similar to that of bilateral adrenal hyperplasia. Mean serum corrected calcium level was $8.9{\pm}0.3mg/dL$ (range, 8.3 to 9.9). The corrected calcium level had a negative linear correlation with left ventricular end-diastolic diameter (LVEDD, ${\rho}=-0.424$, P=0.031). Moreover, multivariable regression analysis showed that the corrected calcium level was marginally associated with the LVEDD and corrected QT (QTc) interval (${\beta}=-0.366$, P=0.068 and ${\beta}=-0.252$, P=0.070, respectively). Conclusion: Aldosterone-mediated hypercalciuria and subsequent hypocalcemia may be partly involved in the development of cardiac remodeling as well as a prolonged QTc interval, in subjects with PA, thereby triggering deleterious effects on target organs additively.

• 대한임상독성학회지
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• 제18권2호
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• pp.130-135
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• 2020

Purpose: Taking large amounts of glyphosate is life-threatening, but the amounts of glyphosate taken by patients for suicide are not known precisely. The purpose of this study was to find the predictors of large amounts of glyphosate ingestion. Methods: This retrospective study analyzed patients presenting to an emergency department with glyphosate intoxication between 2010 and 2019, in a single tertiary hospital. The variables associated with the intake amounts were investigated. The parameters were analyzed by multivariate variate logistic regression analyses and the receiver operating characteristic (ROC) curve. Results: Of the 28 patients with glyphosate intoxication, 15 (53.6%) were in the large amounts group. Univariate analysis showed that metabolic acidosis, lactic acid, and corrected QT (QTc) interval were significant factors. In contrast, multivariate analysis presented the QTc interval as the only independent factor with intoxication from large amounts of glyphosate. (odds ratio, 95% confidence interval: 1.073, 1.011-1.139; p=0.020) The area under the ROC curve of the QTc interval was 0.838. Conclusion: The QTc interval is associated significantly with patients who visit the emergency department after being intoxicated by large amounts of glyphosate. These conclusions will help in the initial triage of patients with glyphosate intoxication.

• 대한한의학회지
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• 제43권1호
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• pp.33-41
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• 2022

Objectives: Drug-induced blockade of the human ether-à-go-go related gene (hERG) potassium ion channel causes acquired long QT syndrome, which is known to cause cardiac arrhythmias and be fatal. To establish safety evidence of herbal formulae, we evaluated the effects of 31 herbal formulae on hERG channel activity. Methods: The current through hERG channel was measured by changing the membrane voltage before and after treatment with 31 herbal formulae in HEK 293 cell overexpressing hERG channel using a whole-cell patch clamp system. The current-voltage curves and the activity curves were fitted, and the hERG activity and 50% inhibitory concentration (IC₅₀) according to each herbal formula were calculated. Results: Chokyungjongok-tang, Oncheong-eum, and Cheongsangbangpung-tang strongly inhibited the hERG activity, with IC₅₀ values of 67.67, 141.2, and 296.3 ㎍/mL, respectively. Yeonkyopaedok-san, Eunkyo-san, Ukgan-san gajinphibanha, Daegunjoong-tang (except Oryzae gluten), Insamyangyoung-tang, Banhahubak-tang, SokyungHwalhyul-tang, Jodeung-san, Hyeonggaeyeongyo-tang, and Bangkeehwangkee-tang weakly inhibited hERG activity, with IC₅₀ values ranging from 400 to 1000 ㎍/mL. The other 18 herbal formulae showed very weak hERG activity inhibition of less than 50% at the highest concentration (1000 ㎍/mL). Conclusion: This study provided safety information on cardiotoxicity by cardiac arrhythmia risk assessment of herbal formulae, and is expected to be a reference data for predicting the safety and risk of herbal formulae.

• 대한한의학회지
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• 제42권3호
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• pp.44-55
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• 2021

Objectives: As the use of herbal medicinal products (HMPs) increases worldwide, systematic verification of the safety of HMPs is required. The induction of cardiotoxicity is one of the major factors in post-approval withdrawal of medicinal products, and drug-induced cardiotoxicity assessment is emerging as an important step in drug development. In the present study, we evaluated human ether-à-go-go-related gene (hERG) potassium channel-related cardiotoxicity to predict the risk of cardiac arrhythmia in thirteen herbal medicines known to have cardiac toxicity. Methods: We measured the inhibition rate of hERG potassium channel activity of 13 medicinal herbal extracts in hERG-expressing HEK 293 cells using an automated patch-clamping system. Quinidine was used as a positive control for inhibition of hERG activity. Results: Extracts of Evodiae Fructus, Strychni Semen, and Corydalis Tuber potently inhibited the activity of hERG, and IC₅₀ values were 3.158, 19.87, and 41.26 ㎍/mL, respectively. Cnidi Fructus, Ephedra Herba, Lithospermi Radix, Polygoni Multiflori Radix, Visci Ramulus et Folium, Asiasari Radix et Rhizoma, and Scolopendra weakly inhibited hERG activity, and the IC₅₀ value for each herbal medicine was more than 400 ㎍/mL. Aconiti Kusnezoffii Tuber and two types of Aconiti Lateralis Radix Preparata (Po and Yeom) had weak inhibitory activity against hERG, and the IC₅₀ values were more than 700 ㎍/mL. The IC₅₀ value of quinidine against hERG was 1.021 𝜇M. Conclusion: Evodiae Fructus, Strychni Semen, and Corydalis Tuber acted as potent inhibitors against hERG. These herbal medicines may cause cardiac arrhythmia through QT prolongation, so care should be taken when taking them.

• 열처리공학회지
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• 제36권1호
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• pp.7-14
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• 2023

We investigated the effect of multiple tempering on the microstructure and mechanical properties of AISI 4340 steel. The austenitized and quenched AISI 4340 steels were tempered at 550, 600, and 650℃ for 1, 2, and 4 h by single-tempering (ST). The multiple tempering was conducted for 4 h by double-tempering (DT, 2 h + 2 h), and quadruple-tempering (QT, 1 h + 1 h + 1 h + 1 h). As tempering temperature increases, yield strength and ultimate tensile strength decrease and elongation increases due to recovery and recrystallization of martensite and coarsening of carbides. At 550℃, as the number of tempering cycles increases, the yield strength and tensile strength decrease at the expense of fracture elongation. At 600 and 650℃, the yield strength and tensile strength increase with increasing the number of tempering cycles while fracture elongation maintains similar values. The multiple tempering at the same tempering time of 4 h improves the modulus of toughness at all tempering temperatures, which is presumed to be due to the change in carbide precipitation behavior by multiple tempering.

• Nuclear Engineering and Technology
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• 제55권10호
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• pp.3854-3859
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• 2023

Background: This study aims to develop an evaluator that can quickly and accurately evaluate the shielding of low-energy industrial radiation generators. Methods: We used PyQt to develop a graphical user interface (GUI)-based program and employed the calculation methodology reported in the National Council on Radiation Protection and Measurements (NCRP)-49 for shielding calculations. We gathered the necessary factors for shielding evaluation using two libraries designed for Python, pandas and NumPy, and processed them into a database. We verified the effectiveness of the proposed program by comparing the results with those from safety reports of six domestic facilities. Results: After verifying the effectiveness of the program using the NCRP-49 example, we obtained an average error rate of 1.73%. When comparing the facility safety report and results obtained using the program, we found that the error rate was between 1.09% and 6.51%. However, facilities that did not use a defined shielding methodology were underestimated by 31.82% compared with the program (the final barrier thickness satisfied the shielding standard). Conclusion: The developed program provides a fast and accurate shielding evaluation that can assist personnel that work in radiation generator facilities and government officials in reviewing safety.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.34.1-34.8
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• 2023

Background: Hydrogen sulfide is a toxic substance that humans can be exposed to occupationally, and cases of hydrogen sulfide poisoning of workers in industrial sites are commonly reported. However, there have been no cases of poisoning of the public due to an unauthorized discharge of wastewater, so it is important to describe this incident. Case presentation: In a small village in Jeollanam-do, Republic of Korea, accounts of a terrible stench had been reported. A 26-year-old man who lived and worked in a foul-smelling area was taken to the emergency room with a headache, dizziness, nausea, and repeated syncope. A subsequent police and Ministry of Environment investigation determined that the cause of the stench was the unauthorized discharge of 9 tons of wastewater containing hydrogen sulfide through a stormwater pipe while the villagers were sleeping. The patient had no previous medical history or experience of symptoms. Leukocytes and cardiac markers were elevated, an electrocardiogram indicated biatrial enlargement, left ventricular hypertrophy, and corrected QT interval prolongation. Myocardial hypertrophy was detected on a chest computed tomography scan, and hypertrophic cardiomyopathy was confirmed on echocardiography. After hospitalization, cardiac marker concentrations declined, symptoms improved, and the patient was discharged after 7 days of hospitalization. There was no recurrence of symptoms after discharge. Conclusions: We suspect that previously unrecognized heart disease manifested or was aggravated in this patient due to exposure to hydrogen sulfide. Attention should be paid to the possibility of unauthorized discharge of hydrogen sulfide, etc., in occasional local incidents and damage to public health. In the event of such an accident, it is necessary to have government guidelines in place to investigate health impact and follow-up clinical management of exposed residents.

• 한국임상수의학회지
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• 제30권6호
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• pp.456-458
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• 2013

포획된 건강한 너구리들의 심전도의 기준값을 평가하는 것이 본 논문의 주된 목적이다. 41마리의 방목되고 있는 다 자란 너구리들이 강원대학교 야생동물구조센터에 의해 구조되었으며 본 논문에 이용되었다. 어떠한 화학적 보정도 사용하지 않고 6-유도 심전도를 측정하였다. 평균 심박수는 $146.10{\pm}43.31$ 박동수/분 이었다(95% 신뢰구간 132.84~159.36 박동수/분). 평균 호흡수는 $35.73{\pm}11.56$ 호흡수/분 이었다(95% 신뢰구간 32.19~39.27 호흡수/분). 평균 수축기 압력은 $136{\pm}29.26mmHg$ 이었다(95% 신뢰구간 127.99~145.91 mmHg). 모든 너구리들의 심전계의 특징들을 또한 평가하였다. P-파의 평균 너비와 높이는 $38.2{\pm}4.0ms$ (범위 28-40 ms) 와 $0.128{\pm}0.039mV$ (범위 0.09~0.20)이었다. QRS파의 평균 너비와 높이는 $48.5{\pm}7.2ms$ (범위 36-60 ms) 와 $1.330{\pm}0.650mV$ (범위 0.15~2.30)이었다. 평균전기축 (QRS)은 $-91^{\circ}{\sim}+96^{\circ}$ ($10^{\circ}{\sim}60^{\circ}$; 95% 신뢰구간)이었다. 평균 교정 QT 간격(QTc)은 $273.7{\pm}32.7ms$ (범위 212-333 ms)이었고, PR간격은 $76.1{\pm}10.0ms$ (범위 50-82 ms)이었다. 본 논문은 포획된 건강한 너구리들의 심전도(ECG)의 기준값을 제공하는 최초의 논문이다.

• Clinical and Experimental Pediatrics
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• 제52권12호
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• pp.1364-1369
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• 2009

목 적 : 이번 연구에서는 소아기에 흔한 선천성 심장병 환자들을 대상으로 개심술 이후 생긴 반흔과 수술로 인한 용적 또는 압력 과부하 상태의 변화로 초래되는 비정상적인 심실 활성화를 신호 평준화 심전도를 이용하여 분석하고자 하였다. 방 법 : 선천성 심장병으로 개심교정술을 시행한 환자 52명을 대상으로 하였다. 환자군은 우심실 용적 과부하군(심방 중격 결손군, 1군), 좌심실 용적 과부하군(심실 중격 결손군, 2군), 우심실 압력 과부하군(활로씨 4징군, 3군)으로 나누었다. 대상 환자 모두에서 표준 12 유도 심전도와 신호 평준화 심전도 검사를 시행하였고, 평균 QRS 기간, QT와 QTc 간격, f-QRS, HFLA, RMS in terminal 40 ms를 구하였다. 결 과 : 수술 전에는 1군에서 다른 군에 비해 의미 있게 긴 QRS 기간을 보였고(P=0.011), 수술 후에는 3 군에서 다른 군에 비해 QTc 간격이 의미 있는 증가가 있었다(P=0.004). 그러나 신호 평준화 심전도는 수술 전후 환자군 간에 차이가 없었다. 전체 대상 환자 중 신호 평준화 심전도 측정값이 한가지 이상 후전위의 진단 기준에 해당되는 경우가 수술 전 12명(23%)에서 수술 후 21명(40%)로 증가하였다. 특히 2군과 3군에서는 수술 전에 비해 수술 후에 신호 평준화 심전도의 이상 소견을 보이는 경우가 의미있게 많았다(2군: 20% versus 28%, P<0.001, 3군: 14% versus 64%, P<0.001). 결 론 : 비정상적인 신호 평준화 심전도 값은 수술 후 반흔뿐만 아니라 개심술 자체, 심실의 과부하에 의해서도 발생할 수 있다.