• BMB Reports
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• 제48권3호
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• pp.131-138
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• 2015

Cardiac hypertrophy is a form of global remodeling, although the initial step seems to be an adaptation to increased hemodynamic demands. The characteristics of cardiac hypertrophy include the functional reactivation of the arrested fetal gene program, where histone deacetylases (HDACs) are closely linked in the development of the process. To date, mammalian HDACs are divided into four classes: I, II, III, and IV. By structural similarities, class II HDACs are then subdivided into IIa and IIb. Among class I and II HDACs, HDAC2, 4, 5, and 9 have been reported to be involved in hypertrophic responses; HDAC4, 5, and 9 are negative regulators, whereas HDAC2 is a pro-hypertrophic mediator. The molecular function and regulation of class IIa HDACs depend largely on the phosphorylation-mediated cytosolic redistribution, whereas those of HDAC2 take place primarily in the nucleus. In response to stresses, posttranslational modification (PTM) processes, dynamic modifications after the translation of proteins, are involved in the regulation of the activities of those hypertrophy-related HDACs. In this article, we briefly review 1) the activation of HDAC2 in the development of cardiac hypertrophy and 2) the PTM of HDAC2 and its implications in the regulation of HDAC2 activity.

• 대한수의학회지
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• 제55권1호
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• pp.47-52
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• 2015

The purpose of this study was to determine if contrast media would enhance visualization of the endocardium for assessment of left ventricle (LV) function. In addition, differences between pre- and post-contrast evaluation for the cardiac output measurements including the modified Simpson's method and automated contour tracking (ACT) method were examined. Ten clinically healthy adult beagle dogs (three males and seven females) between 2~3 years old and weighing 6.6~10.8 kg were used. Echocardiographic examinations were performed to compare pre- and post-contrast LV endocardium visualization using a segmental scoring method. Two different methods for measuring cardiac output were also compared. LV visualization was significantly enhanced in post-contrast echocardiography (p < 0.01). Significant differences between pre- and post-contrast measurements for the modified Simpson's method (p < 0.05) were also observed. No significant difference was found for the ACT method. Contrast echocardiography provides better LV chamber opacification and significantly improves wall segment visualization. Furthermore, contrast echocardiography for measuring cardiac output is helpful for the modified Simpson's method.

• Journal of Chest Surgery
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• 제31권4호
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• pp.398-401
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• 1998

단극유도의 심박조율기를 가진 56세 여자환자에서 관상동맥 우회로술과 승모판 치환술을 시행하였다. 이러한 단극유도 심박조율기는 심근 외의 전자기의 간섭에 대한 감수성이 높으므로 개심술시 전기소작기의 전기파에 의해 심박조율기의 조율기능이 억제될 수 있으며, 수술후 제세동기 사용할 때 영구 심박조율기에 전기 충격이 갈 수 있다. 따라서 대동맥 차단 감자를 해제한 후 심실세동없이 정상 심박동을 유도해야 한다. 본 환자에서 임시형 심방실 유도를 거치하고 임시형 심박조율기로 조율하여 심장리듬과 심기능을 유지시키면서 전기소작기를 사용할 수 있었으며, 대동맥 차단 중 전행성 및 역행성으로 혈성심정지액을 투여하고 대동맥 차단감자를 해제하기 직전에는 온혈심정지액과 온혈의 순차적인 역행성 주입으로 자연적인 심장리듬을 회복시킴으로써 제세동기 사용을 배제할 수 있었다.

• Applied Microscopy
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• 제50권
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• pp.9.1-9.8
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• 2020

The fine structural characteristics of cardiac muscle cells and its myofibril organization in the orb web spider N. clavata were examined by transmission electron microscopy. Although myofibril striations are not remarkable as those of skeletal muscles, muscle fibers contain multiple myofibrils, abundant mitochondria, extensive sarcoplasmic reticulum and transverse tubules (T-tubules). Myofibrils are divided into distinct sarcomeres defined by Z-lines with average length of 2.0 ㎛, but the distinction between the A-band and the I-bands is not clear due to uniform striations over the length of the sarcomeres. Dyadic junction which consisted of a single T-tubule paired with a terminal cisterna of the sarcoplasmic reticulum is found mainly at the A-I level of sarcomere. Each cell is arranged to form multiple connections with neighboring cells through the intercalated discs. These specialized junctions include three types of intercellular junctions: gap junctions, fascia adherens and desmosomes for heart function. Our transmission electron microscopy (TEM) observations clearly show that spider's cardiac muscle contraction is controlled by neurogenic rather than myogenic mechanism since each cardiac muscle fiber is innervated by a branch of motor neuron through neuromuscular junctions.

• 한국재난정보학회:학술대회논문집
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• 한국재난정보학회 2023년 정기학술대회 논문집
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• pp.129-130
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• 2023

The From COVID-19 until recently, the demand for hiking has been rapidly increasing due to the popularization of mountain seekers.,On weekends and holidays, people who do not hike frequently while hiking in large and small mountains to see wildflowers and foliage in the mountains are more likely to be exposed to safety accidents due to an increase in sudden muscle use.,If you fall or get muscle damage during a hike, you can prevent a major accident with a simple treatment. In some cases, the error of first aid may permanently damage the important function of the body.,In particular, during a safety accident on a mountain, while climbing in light clothes, the body temperature rises due to the sweat that was shed at the beginning, and the blood pressure rises due to the contraction of the blood vessels due to the drop in body temperature from the top, resulting in an emergency such as cardiac arrest.,According to statistics from the National Park Service, nearly half (48%) of deaths in national parks are known to be sudden cardiac deaths.,There are many safety accidents that occur frequently in the mountains, but among them, we will study how to cope with acute diseases such as cardiac arrest due to increased blood pressure due to insufficient body temperature control, chest pain or dyspnea, and heart burden due to excessive hiking.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.1-7
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• 2002

Congenital Long QT syndrome (LQTs) is a relatively rare pathologic disorder but results frequently in sudden cardiac death. Of the six LQTs that have been clinically described, five have been worked out for their genetic and biophysical profile. Most are generated by mutations which cause a loss of function in two delayed $K^+$ currents, $i_{Ks}\;and\;i_{Kr}.$ One syndrome is generated by mutations in the $Na^+$ channel which causes essentially a gain of function in the channel. Clinically the syndromes are characterized by slowed repolarization of the cardiac ventricular action potential and the occurrence of typical arrhythmias with undulating peaks in the electrocardiogram, called Torsade de Pointes. Arrhythmias are initiated by early or delayed afterdepolarizations and continue as reentry. Triggers for cardiac events are exercise (swimming; LQT1), emotion (arousal; LQT2) and rest/sleep (LQT3). ${\beta}-blockers$ have a high efficacy in the treatment of LQT1 and LQT2. In LQT3 their use is questionable. The study of congenital LQTsyndromes is a remarkable example of how basic and clinical science converge and take profit of each other's contribution.

• The Korean Journal of Physiology and Pharmacology
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• 제3권6호
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• pp.579-586
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• 1999

Complement-mediated neutrophil activation has been hypothesized to be an important mechanism of reperfusion injury. It has been proposed that C1 esterase inhibitor (C1 INH) may prevent the complement- dependent activation of polymorphonuclear leukocytes (PMNs) that occurs within postischemic myocardium. Therefore, The effect of C1 INH was examined in neutrophil dependent isolated perfused rat heart model of ischemia (I) (20 min) and reperfusion (R) (45 min). Administration of C1 INH (5 mg/Kg) to I/R hearts in the presence of PMNs $(100{\times}10^6)$ and homologous plasma improved coronary flow and preserved cardiac contractile function (p＜0.001) in comparison to those I/R hearts receiving only vehicle. In addition, C1 INH significantly (p＜0.001) reduced PMN accumulation in the ischemic myocardium as evidenced by an attenuation in myeloperoxidase activity. These findings demonstrate the C1 INH is a potent and effective cardioprotective agent inhibits leukocyte-endothelial interaction and preserves cardiac contractile function and coronary perfusion following myocardial ischemia and reperfusion.

• Journal of Chest Surgery
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• 제21권2호
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• pp.246-253
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• 1988

An in vitro model providing with a recirculating perfusion apparatus using an isolated canine heart and its autogenous blood, which was prepared for study of myocardial protection method. This apparatus was easily used by quick connect system and maintained well heart function for about 2 hours. The Langendorff perfusion was initiated for a 10 minute period by introducing perfusate at 37` into the aorta from aortic reservoir located 100 cm above the heart. The isolated perfused working canine heart model was a left heart preparation in which oxygenated perfusion medium [at 37K] entered the cannulated left atrium at a constant flow rate [900ml/ min] under 20 mmHg overflow system and was spontaneously ejected[no electrical pacing] via an cannula against a hydrostatic pressure of 80 cm H2O. During this working period, various indices of cardiac function were measured. The cardiac functions were stable for over 2 hours with perfusion of Krebs-Henseleit solution and autologous blood[1:1] mixture in volume and maintained heart rate ]]3-122/bpm peak systolic pressure 109-113 mmHg, cardiac output 900 ml / min and left atrial mean pressure 8-9 mmHg. In this model, the efficiency of myocardia] protection could be easily measured by means of functional, enzymatic, biochemical and ultrastructural assessment. And also, we believe this model to be a useful assessment screening model of recovery state after long duration of myocardial preservation of donor heart without difficult transplantation procedures.

• 대한약리학회지
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• 제14권1_2호
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• pp.41-46
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• 1978

The effects of sodium taurocholate(STC) and sodium deoxycholate(SDC) on cardiac function were examined by using isolated atria of rabbit and guinea pig and heart of anesthetized frog. Also the antiarrythmic action of STC and SDC on atrial arrhythmias induced by epinephrine or ouabain was studied. The results were following. The cholates exhibited a slight decrease in rate and contractile amplitude of the isolated rabbit atria. The cholates abolished partially the spontaneous arrhythmic occurring in isolated rabbit and guinea pig atria but no effect on the atrial arrhythmia induced by ouabain and epinephrine was observed. Concomitant administration of cholates with ouabain produced a marked prolongation of atrial arrhythmia in comparison to that of ouabain alone in both isolated rabbit and guinea pig atria. The cholates exhibited a marked prolongation in ventricular arrhythmia and cardiac arrest time in comparison to that of ouabain treatment. However, the combined treatment with cholates and ouabain produced a slight prolongation in comparison to that of ouabain alone in the heart of anesthetized frog. The above results suggest that cholates have a slight antiarrythmic effect on the heart but this effectiveness is different from those of propranolol that is non-selective antiarrhythmic drug.

• Journal of Chest Surgery
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• 제57권2호
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• pp.225-229
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• 2024

Venovenous (VV) extracorporeal membrane oxygenation (ECMO) is a lifesaving technique for patients experiencing respiratory failure. When VV ECMO fails to provide adequate support despite optimal settings, alternative strategies may be employed. One option is to add another venous cannula to increase venous drainage, while another is to insert an additional arterial return cannula to assist cardiac function. Alternatively, a separate ECMO circuit can be implemented to function in parallel with the existing circuit. We present a case in which the parallel ECMO method was used in a 63-year-old man with respiratory failure due to coronavirus disease 2019, combined with cardiac dysfunction. We installed an additional venoarterial ECMO circuit alongside the existing VV ECMO circuit and successfully weaned the patient from both types of ECMO. In this report, we share our experience and discuss this method.