• YAKHAK HOEJI
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• v.51 no.5
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• pp.301-306
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• 2007

Rosiglitazone ($Avandia^{(R)}$) represents a new class of antidiabetic drugs which are $PPAR{\gamma}$ agonists. The present study was undertaken to determine whether the new antidiabetic rosiglitazone influences on the agonist-induced regulation of vascular smooth muscle contraction as an antihypertensive and, if so, to investigate the related mechanism. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Rosiglitazone decreased Rho-kinase activating agonist (NaF or thromboxane $A_2$ mimetic)-induced contraction but not depolarization- or phorbol ester-induced contraction. Surprisingly, it slightly potentiated the latter contraction possibly opening a voltage-dependent calcium channel by its chemical structure on 50 mM KCI- or $1{\mu}M$ phorbol 12,13-dibutyrate-induced vasoconstriction. In conclusion, this study provides the evidence and possible related mechanism concerning the biphasic effect of an antidiabetic rosiglitazone as a possible antihypertensive on the agonistinduced contraction in rat aortic rings regardless of endothelial function.

• The Korean Journal of Cytopathology
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• v.10 no.1
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• pp.73-78
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• 1999

Myxopapillary ependymoma generally arise in the conus medullaris and filum terminale of adult spinal cord. These tumors are readily recognized due to unique histopathologic features, however, their cytologic features are not well described. When only a tiny sample is obtained, cytologic examination using crush preparation may be a useful diagnostic tool to help appropriate intraoperative diagnosis. We present the crush cytologic features of myxopapillary ependymoma arising in thoracic and lumbar spinal cord of a 13-year-old boy. The patient had complained of paraparesis and back pain for 1 month. The MRI image revealed a relatively well demarcated intramedullary mass in T11-L1 levels. Crush preparation for cytology were peformed by biopsy material. Crush cytologic findings revealed high cellularity and small sized branching papillary clusters on fibrillary or mucinous background. The tumor cells had uniform round or elongated nuclei. The cytoplasmic process of tumor cells were attached to the vascular wall. Between the tumor cells and vascular walls, the perivascular collar of globoid acellular stroma with metachromatic reaction on toluidin blue stain was noted. The crush preparation of myxopapillary ependymoma is considered as a simple and highly accurate diagnostic tool for differentiation from other intramedullary neoplasms of central nervous system.

• Tuberculosis and Respiratory Diseases
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• v.76 no.6
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• pp.295-298
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• 2014

Pulmonary systemic arterialization to normal basal lung without sequestration is a rare congenital anomaly. In this rare abnormality, arterialization of the left lower lobe is the most common type. In general, surgical treatments have been performed. Recently, for reducing the complications and risks of surgery, embolization is mainly attempted by using coils. We report a case of 22-year-old male patient with a 10 mm anomalous arterial supply to his normal lung, which is being successfully treated by transcatheter embolization when using the Amplatzer Vascular Plug that has been adapted for the treatment of high-flows and large artery occlusions.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.318-326
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• 1999

Apoptotic cell death, characterized by DNA fragmentation and morphological changes, has previously been shown to occur in vascular endothelial cells cultured with hydrogen peroxide. The present study examined the induction of apoptosis by hydrogen peroxide and whether pyruvate, a key glycolytic intermediate and $\alpha$-keto-monocarboxylate, can inhibit the apoptotic effects in bovine pulmonary artery endothelial cells(BPAECs). Culture with 500uM hydrogen peroxide resulted in 30% cell death and induced morphological changes and DNA fragmentation. Cell injury was inhibited by the treatment with pyruvate. Pyruvate(0.1-5.0mM), and cell viability increased in a dose-dependent manner. In the presence of pyruvate(10~20mM), the viability was improved to over 95%. In contrast, treatment with lactate, a reduced form of phyuvate, did not protect against cell death oxidative stress-induced loss of viability and apoptosis was examined with $\alpha$-cyano-3-hydroxycinnarmate(COHC) as a selective mitochondrial monocarboxylate transport blocker. Incubation with COHC(500uM) did not significantly affect cell viability in the presence of hydrogen peroxide. The cytoprotection by pyruvate(3mM)against hydrogen peroxide stress was abolished by COHC. This indicates that the cytoprotection by pyruvate against oxidative stress in endothelial cells is mediated, at least in part, by mitochondrial pyruvate uptake and hence endothelial enerygetics. However, cytosolic mechanisms related, at least in part, by mitochondrial pyruvate uptake and hence endothelial energetics. However, cytosolic mechanisms related to the glutathione system may also contribute. The results suggest that pyruvate has therapeutic potential in the treatment of oxidative stress-induced cytotoxicity associated with increased apoptosis.

• YAKHAK HOEJI
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• v.55 no.2
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• pp.138-144
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• 2011

The aim of present study was to investigate the possible influence and related mechanism of resveratrol on U-46619 (high concentration)-induced vasoconstriction. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in resveratrol-induced relaxation in rat aortae contracted with high U-46619. We hypothesized that MEK or Rho-kinase inhibition plays a role in vascular relaxation evoked by resveratrol in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Resveratrol fully inhibited U-46619 in low concentration-induced contraction regardless of endothelial function. However, resveratrol partially decreased U-46619 in high concentration-induced contraction regardless of endothelial function. Interestingly, only in U-46619 (high concentration)-induced contraction, no significant decrease was observed in phospho-ERK1/2 levels and slight decrease in phospho-MYPT1 levels suggesting that additional pathways different from them or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in high U-46619-contracted rat aortae, resveratrol showed relaxation response regardless of endothelial function significantly but slightly decreasing MYPT1 phosphorylation rather than ERK1/2 phosphorylation.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.538-543
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• 2020

Cardiovascular diseases are a rapidly growing epidemic with high morbidity and mortality. There is an urgent need to develop nutraceutical-based therapy with minimum side effects to reduce cardiovascular risk. Panax ginseng occupies a prominent status in herbal medicine for its various therapeutic effects against inflammation, allergy, diabetes, cardiovascular diseases, and even cancer, with positive, beneficial, and restorative effects. The active components found in most P. ginseng varieties are known to include ginsenosides, polysaccharides, peptides, alkaloids, polyacetylene, and phenolic compounds, which are considered to be the main pharmacologically active constituents in ginseng. P. ginseng is an adaptogen. That is, it supports living organisms to maintain optimal homeostasis by exerting effects that counteract physiological changes caused by physical, chemical, or biological stressors. P. ginseng possesses immunomodulatory (including both immunostimulatory and immunosuppressive), neuromodulatory, and cardioprotective effects; suppresses anxiety; and balances vascular tone. P. ginseng has an antihypertensive effect that has been explained by its vasorelaxant action, and paradoxically, it is also known to increase blood pressure by vasoconstriction and help maintain cardiovascular health. Here, we discuss the potential adaptogenic effects of P. ginseng on the cardiovascular system and outline a future research perspective in this area.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.392-397
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• 2010

The aim of present study was to investigate the possible influence and related mechanism of additional alcohol on the flavonoid- induced arterial relaxation. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in quercetin-induced relaxation cotreated with alcohol in rat aortae contracted with phorbol ester, fluoride or thromboxane $A_2$ mimetic U-46619. We hypothesized that cotreated alcohol plays a role in vascular relaxation evoked by quercetin in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Quercetin inhibited phorbol ester, fluoride or thromboxane $A_2$-induced contraction regardless of endothelial function. However, alcohol didn't decrease any agonist-induced contraction. Interestingly, only in thromboxane $A_2$-induced contraction, synergistic results were observed in aortae denuded and cotreated with quercetin and alcohol suggesting that additional pathways different from antioxidation or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in the agonists-contracted rat aortae, quercetin and alcohol together showed synergistic response regardless of endothelial function in an agonist-dependent manner.

• Molecules and Cells
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• v.27 no.2
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• pp.191-198
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• 2009

The present study was undertaken to determine whether treatment with genistein, the plant-derived estrogen-like compound influences agonist-induced vascular smooth muscle contraction and, if so, to investigate related mechanisms. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Genistein completely inhibited KCl-, phorbol ester-, phenylephrine-, fluoride- and thromboxane $A_2$-induced contractions. An inactive analogue, daidzein, completely inhibited only fluoride-induced contraction regardless of endothelial function, suggesting some difference between the mechanisms of RhoA/Rho-kinase activators such as fluoride and thromboxane $A_2$. Furthermore, genistein and daidzein each significantly decreased phosphorylation of MYPT1 at Thr855 had been induced by a thromboxane $A_2$ mimetic. Interestingly, iberiotoxin, a blocker of large-conductance calcium-activated potassium channels, did not inhibit the relaxation response to genistein or daidzein in denuded aortic rings precontracted with fluoride. In conclusion, genistein or daidzein elicit similar relaxing responses in fluoride-induced contractions, regardless of tyrosine kinase inhibition or endothelial function, and the relaxation caused by genistein or daidzein was not antagonized by large conductance $K_{Ca}$-channel inhibitors in the denuded muscle. This suggests that the RhoA/Rho-kinase pathway rather than $K^+$- channels are involved in the genistein-induced vasodilation. In addition, based on molecular and physiological results, only one vasoconstrictor fluoride seems to be a full RhoA/Rho-kinase activator; the others are partial activators.

• Research in Plant Disease
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• v.9 no.1
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• pp.36-38
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• 2003

Stem blight of brunfelsia (Brunfelsia calycina) caused by Fusarium oxysporum was found in greenhouse around Sungnam area, Kyunggi province, Korea in September 2001. The initial infection appeared as a slight wilting of the foliage, turned yellow from the lower leaves. The yellowing leaves were falled, resulting in blight of stem and eventual death of the entire plant. The vascular tissue of a diseased plants became dark brown and browning of the vascular system was a characteristic of the disease and the pith remained healthy, Isolates obtained from the lesions of the diseased plant were identified as F. oxysporum, based on the morphological characteristics of conidia. Symptom by artificial inoculation was same to the symptom of naturally infected plants. This is the first report demonstrating the stem blight on a brunfelsia caused by F. oxysporum in Korea, and we proposed to name this disease "stem blight of brunfelsia".

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.192-193
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• 2003

In previous study, we demonstrated tilianin inhibits tumor necrotic factor-${\alpha}$ (TNF-${\alpha}$) induced vascular cell adhesion molecule-1 (VCAM-1) expression in human umbilical vein endothelial cells (HUVEC). In this study, we demonstrate inhibition of the production of atherogenic cytokines and the anti-atherogenic effects of tilianin in Ldlr-/- mice.(omitted)