• Journal of Pharmaceutical Investigation
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• v.26 no.1
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• pp.43-53
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• 1996

The objective of this study was to determine whether 4-phenylazobezyloxycarbonyl-Pro-Leu-Gly-Pro-D-Arg (Pz-peptide), an enhancer of hydrophilic solute permeability in the intestine, could elevate the paracellular permeability of hydrophilic drugs across cornea and conjunctiva in the rabbit. The in-vitro penetration of hydrophilic drugs (mannitol, atenolol) and lipophilic drug (propranolol) across the rabbit cornea and conjunctiva was studied either in the presence or absence of 3 mM Pz-peptide. Drug penetration was evaluated using the modified Ussing chamber. The conjunctiva was more permeable than the cornea to all drugs. Pz-peptide showed enhanced effects on the drug transport across cornea and conjunctiva in a concentration dependent manner. Effects or ion transport inhibitor on the mannitol penetration were then investigated. Mannitol penetration was not changed by serosal addition of $100\;{\mu}M$ ouabain, suggesting that $Na^+/K^+$ ion tranporter was not involved in the Pz-peptide induced elevation of paracellular drug permeability. Furthermore, effects of Pz-peptide and EDTA on the transport of atenolol and propranolol into the ocular tissues or blood circulation after its administration into both eyes were investigated. EDTA showed enhanced effect on propranolol transport into the ocular tissues, but Pz-peptide did not show significant difference. Systemic absorption of propranolol by the addition of EDTA or Pz-peptide was not changed. On the other hand, EDTA and Pz-peptide elavated the atenolol transport into the ocular tissues. The transport of atenolol into the blood circulation was also enhanced by the addition of EDTA, but no effect was observed by the addition of Pz-peptide. The above findings suggest that Pz-peptide would be used as an paracellular pathway enahncer of hydrophilic drugs into the eye, without affecting the systemic absortion of topically applied opthalmic drugs.

• Toxicological Research
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• v.31 no.1
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• pp.49-59
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• 2015

Eye is a highly vascularised organ. There are chances that a foreign substance can enter the systemic circulation through the eye and cause oxidative stress and evoke immune response. Here the eyes of rabbits were exposed, for a period of 7 days, to 5 known ocular irritants: Cetyl pyridinium chloride (CPC), sodium salicylate (SS), imidazole (IMI), acetaminophen (ACT) and nicotinamide (NIC). The eyes were scored according to the draize scoring. Blood collected from the treated rabbit were analyzed for haematological and biochemical parameters. After sacrifice, histological analysis of the eye and analysis of pro-inflammatory biomarkers ($IL-1{\alpha}$, $IL-1{\beta}$, IL-8 and $TNF-{\alpha}$) in the cornea using ELISA was carried out. Spleen was collected and the proliferation capacities of spleenocytes were analyzed. Liver and brain were collected and assessed for oxidative stress. The eye irritation potential of the chemicals was evident from the redness and swelling of the conjunctiva and cornea. Histopathological analysis and ELISA assay showed signs of inflammation in the eye. However, the haematological and biochemical parameters showed no change. Spleenocyte proliferations showed only slight alterations which were not significant. Also oxidative stress in the brain and liver were negligible. In conclusion, chemicals which cause ocular irritation and inflammation did not show any systemic side-effects in the present scenario.

• Journal of Chest Surgery
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• v.31 no.4
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• pp.409-412
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• 1998

This is a case report of an operation for the pulmonary arteriovenous fistula supplied from the systemic arteries instead of the pulmonary artery. The operation of systemic arteriovenous pulmonary fistula has formidable technical challenges due to its extensive collateral circulations. A 16 year-old female patient, diagnosed as systemic arteriovenous fistula with multiple tortuous feeding vessels and with hereditary hemorrhagic telangiectasia, was initially managed with arterial embolization before the operation. A 15${\times}$8cm sized huge vascular malformation was removed by RML and RLL bilobectomy. During the operation, we encountered annoying massive bleeding and pulmonary congestion originated in its extensive collateral circulation. The patient was discharged after conservative management without specific problem on the 15th postoperative day. For the safe operation as well as good operative result, it seemed that meticulous ligation of the multiple collateral vessels should be performed prior to that of pulmonary veins.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.12
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• pp.1164-1171
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• 2004

A new multi-scale simulation model is proposed to analyze heart mechanics. Electrophysiology of a cardiac cell is numerically approximated using the previous model of human ventricular myocyte. The ion transports across cell membrane initiated by action potential induce an excitation-contraction mechanism in the cell via cross bridge dynamics. Negroni and Lascano model (NL model) is employed to calculate the tension of cross bridge which is closely related to the ion dynamics in cytoplasm. To convert the tension on cell level into contraction force of cardiac muscle, we introduce a simple geometric model of ventricle with a thin-walled hemispheric shape. It is assumed that cardiac tissue is composed of a set of cardiac myocytes and its orientation on the hemispheric surface of ventricle remains constant everywhere in the domain. Application of Laplace law to the ventricle model enables us to determine the ventricular pressure that induces blood circulation in a body. A lumped parameter model with 7 compartments is utilized to describe the systemic circulation interacting with the cardiac cell mechanism via NL model and Laplace law. Numerical simulation shows that the ion transports in cell level eventually generate blood hemodynamics on system level via cross bridge dynamics and Laplace law. Computational results using the present multi-scale model are well compared with the existing ones. Especially it is shown that the typical characteristics of heart mechanics, such as pressure volume relation, stroke volume and ejection fraction, can be generated by the present multi-scale cardiovascular model, covering from cardiac cells to circulation system.

• Journal of Chest Surgery
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• v.51 no.1
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• pp.53-56
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• 2018

Patients with double-inlet left ventricle usually have a small ascending aorta. In the Norwood procedure, which involves a staged operation, a neoaorta is constructed with a homograft, and the pulmonary artery plays a role in the systemic circulation. Dilatation or aneurysmal changes can occur over time due to the exposure of the neoaorta to systemic pressure, which may induce adverse effects on adj acent structures. We report a rare case of surgical repair for neoaortic root dilataiton with aortic regurgitation, compressing the left pulmohary artery, in a patient who underwent the Norwood procedure.

• Journal of Oral Medicine and Pain
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• v.26 no.2
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• pp.157-160
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• 2001

Facial nerve paralysis(or Bell's palsy) which commonly occurs unilaterally, gives rise to paralysis of facial expression muscle. This condition is classified into symptomatic facial nerve paralysis due to intracranial tumor, post operative trauma, etc. and idiopathic facial nerve paralysis. To explain the etiology of idiopathic facial nerve paralysis, many hypothesis including ischemic theory, viral infection, exposure to cold, immune theory etc. were suggested, but there is no agreement at this point. The method to evaluate the facial nerve paralysis, when it occurs, consists of three stage scale method, image thechnics like CT and MRI, laboratory test to examine the antibody titers of viral infection, neurophysiologic test to evaluate the degree and prognosis of paralysis. Treatment includes medication, stellate ganglion block(SGB), surgery, physical therapy and other home care therapy. In medication, systemic steroids, vitamins, vasodilating-drug and ATP drugs were used. SGB was also used repeatedly to attempt the improvement of circulation and to stimulate the recovery of nerve function. Physical therapy including electric acupuncture stimulation therapy(EAST) and hot pack was used to prevent the muscle atrophy. When No response was showed to this conservative therapies, surgery was considered. After treating two patients complaining of Bell's palsy with medication(systemic steroids) and EAST, favorable result was obtained. so author report the case of facial nerve paralysis.

• Archives of Pharmacal Research
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• v.8 no.3
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• pp.177-186
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• 1985

Effect of food on the absorption characteristics of oral rifampicin was studied in the fasted rats. Rifampicin dissolved in a new cosolvent was also injected to the rats intravenously, and the pharmacokinetic analysis was performed to explain the effect of food on the gastrointestinal absorption of rifampicin. Rifampicin was absorbed rapidly and completely in the fasting state. Food had a profound effect on the gastrointestinal absorption of rifampicin, i. e., bioavailability and the extent of absorption were decreased to less than one-third of the fasting state in the postprandial state. Food seemed to imhibit the absorption and reabsorption of rifampicin in the gastrointestinal tract, but not the absorption rate constant. Hepatobiliary excretion seemed to be the major route of elimination, since the renal clearance accounted for only 8 % of the systemic clearance. Nevertheless, first-pass effect was negligibly small and most of rifampicin absorbed could reach systemic circulation. Serum concentration change of oral rifampicin on multiple dosing differed markedly in the fasting and postprandial state, which suggested the need of careful adjustment of dosage regimen in both states.

• Korean Circulation Journal
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• v.52 no.4
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• pp.251-264
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• 2022

Heart failure with preserved ejection fraction (HFpEF) accounts for approximately half of all heart failure (HF) cases. The prevalence of HFpEF is increasing due to an aging population with hypertension, diabetes mellitus, and obesity. HFpEF remains a challenging clinical entity due to a lack of effective treatment options. Traditional HF medications have not been shown to reduce mortality of patients with HFpEF, and an implantable cardioverter-defibrillator is not indicated due to normal ejection fraction. Sudden death is the most common mode of death in patients with HFpEF; however, the underlying mechanisms of sudden death are not fully elucidated. Although ventricular arrhythmias are responsible for the majority of sudden deaths in general, their contribution to sudden deaths in HFpEF patients is likely less significant. The mechanisms of ventricular arrhythmias in HFpEF are 1) reduced conduction velocity due to ventricular hypertrophy, 2) delayed repolarization due to potassium current down-regulation, 3) calcium leakage due to altered excitation-contraction coupling, and 4) increased ventricular fibrosis caused by systemic inflammation. Hypertension and subsequent ventricular hypertrophy reduce the conduction velocity in HFpEF hearts via heterogeneous distribution of connexin 43. Delayed repolarization caused by potassium current down-regulation in HFpEF hearts provides a window for early afterdepolarization to trigger ventricular arrhythmias. Altered excitation-contraction coupling in HFpEF can cause calcium to leak and trigger delayed afterdepolarization. Increased systemic inflammation and subsequent ventricular fibrosis provide substrates for re-entry. Further research is warranted to investigate the detailed mechanisms of ventricular arrhythmias in HFpEF.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.86-88
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• 2010

Implanting a pacemaker is the most often used intervention for treating bradycardia. The most commonly used pacemaker is the intracardiac pacemaker, yet it can have many complications. An infected pacemaker can spread to systemic infection and the condition of the patient can quickly get worse, so if an infected pacemaker is suspected, then the pacemaker must be removed. Apart from the use of interventional methods such as a loop or a weight, we can take a more aggressive approach by using extracorporeal circulation for removal of the pacemaker. We report here on two cases in which extracorporeal circulation was used to remove the infected pacemakers.

• Journal of Korean Neurosurgical Society
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• v.61 no.4
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• pp.467-473
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• 2018

Objective : The aim of this study was to determine outcome of ischemic stroke patients in the anterior circulation treated with endovascular treatment (EVT) with intravenous thrombolysis (IVT) versus EVT alone group. Methods : A systemic literature review was performed using online database from January 2004 to January 2017. Primary outcomes were successful recanalization seen on finial angiography and good outcome at three months. Secondary outcomes were mortality and the development of symptomatic intracranial hemorrhage (S-ICH) after the procedure. A fixed effect model was used when heterogeneity was less than 50%. Egger's regression test was used to assess publication bias. Results : Five studies were included for final analysis. Between EVT with IVT and EVT alone group, successful recanalization (odds ratio [OR] 1.467, p=0.216), good clinical outcome at three months (OR 1.199, p=0.385), mortality (OR 0.776, p=0.371), and S-ICH (OR 1.820, p=0.280) did not differ significantly. Egger's regression intercept with 95% confidence interval (CI) was 1.99 (95% CI -2.91 to 6.89) in successful recanalization and -0.27 (95% CI -6.35 to 5.80) in good clinical outcome, respectively. Conclusion : The two treatment modalities, EVT with IVT and EVT alone, could be comparable in treating acute anterior circulation stroke. Studies to find specific beneficiary group for EVT alone, without primary IVT, are needed further.