• Journal of Sensor Science and Technology
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• v.22 no.1
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• pp.76-83
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• 2013

A real-time wireless monitoring and analysis methods using the wearable PPG sensor to estimate cardiovascular condition is studied for ubiquitous healthcare service. A small size and low-power consuming wearable photoplethysmogram (PPG) sensor is designed as a wrist type device and connected with the IP node assigned its own IPv6 address. The measured PPG waveform in the IP node is collected and transferred to a central server PC through the IP-enabled wireless network for storage and analysis purposes. A monitoring and analysis program is designed to process the accelerated plethysmogram (APG) waveform by applying the second order derivatives to analyze systolic waves as well as heart rate variability analysis from the measured PPG waveform. From our results, the features of cardiovascular condition from individual's PPG waveform and estimation of vascular compliance by the comparison of APG-aging index (AI) and ratio of LF/HF are demonstrated.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.2
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• pp.217-223
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• 1998

Oxygen-derived free radicals have been implicated in many important functions in the biological system. Electrical field stimulation (EFS) causes arterial relaxation in animal models. We found that EFS applied to neither muscle nor nerve but to Krebs solution caused a relaxation of rat aorta that had been contracted with phenylephrine. In the present study, therefore, we investigated the characteristics of this EIRF (electrolysis-induced relaxing factor) using rat isolated aorta. Results indicated that EIRF acts irrespective of the presence of endothelium. EIRF shows positive Griess reaction and is diffusible and quite stable. EIRF-induced relaxation was stronger on PE-contracted aorta than on KCl-contracted one, and inhibited by the pretreatment with methylene blue. Zaprinast, a cGMP-specific phosphodiesterase inhibitor, potentiated the EIRF-induced relaxation. $N^G-nitro-L-arginine$, NO synthase inhibitor, did not inhibit the EIRF-induced relaxation. Deferroxamine, but not ascorbic acid, DMSO potentiated the EIRF-induced relaxation. These results indicate that electrolysis of Krebs solution produces a factor that relaxes vascular smooth muscle via cGMP-mediated mechanism.

• Journal of Korean Neurosurgical Society
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• v.52 no.1
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• pp.48-51
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• 2012

Intravascular papillary endothelial hyperplasia (IPEH) is a rare vascular benign lesion that rarely involves the central nervous system with or without skull invasion. We report a rare case of IPEH on the skull bone, which displayed destructive radiologic development associated with hemorrhage. A 14-year-old male presented with an incidentally detected a small enhancing, left frontal osteolytic lesion. Previously, he underwent operation and received adjuvant chemoradiation therapy for cerebellar medulloblastoma. Follow-up magnetic resonance imaging revealed a left frontal bone lesion, which expanded to an approximately 2 cm-sized well-circumscribed osteolytic lesion associated with hemorrhage for 20 months. Frontal craniectomy and cranioplasty were performed. Destructive change was detected on the inner table and diploic space of the skull. The mass had a cystic feature with hemorrhagic content without dural attachment. Pathologic examination showed the capsule consisted of parallel collagen lamellae representing a vascular wall, vascular lumen, which was pathognomonic for IPEH. Immunohistochemical staining revealed that the capsule was positive for CD34 and factor VIII, which favor the final diagnosis of IPEH. This was the first case of intracalvarial IPEH.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1235-1242
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• 2003

This study was performed for the investigation of vasodilatory effects of Crataegus pinnatifida Bunge and for isolation and structure determination of the constituent from the active fraction. The fruits of this herbal drug were extracted with 80% methanol, then fractioned successively with methylene chloride, ethylacetate and n-butanol. Among the fractions, ethyl acetate fraction exhibited the most effective vascular relaxation against phenylephrine-induced arterial contraction. In order to isolate the active constituent by activity-guided fractionation, this fraction was chromatographed on silica gel to yield seven subfractions. Among the subfractions, the active one showing the most potent vascular relaxation activity was further separated by prep. HPLC with reversed phase Microsorb C-18 column using 1 % acetic acid and methanol gradient solvent system to afford one pure compound, which revealed a potent vasodilatory effect. Instrumental analyses (NMR and mass spectrometry) of the isolated constituent indicated this compound to be (-)-epicatechin. The vasodilatory action mechanism of this compound should be further investigated.

• Applied Microscopy
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• v.21 no.1
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• pp.86-107
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• 1991

An experimental study was performed to observe the early effects of monocrotaline on pulmonary vascular system by means of light microscopy and scanning electron microscopy, attempting to expore the mechanism behind the process of pulmonary hypertension. Experimental animal(Sprague-Dawley male rats ; 150-200g B. W.) were intra-peritoneal administered with 100mg/kg B. W. monocrotaline. Authors observed light microscopically various gradational increase of wall thickness in pulmonary muscular and non-muscular arteries in duration from 2 weeks to 5 weeks after monocrotaline administration and the changes were more sever in the latter than the former. The scanning electron microscopy shows severe and diffuse endothelical cell swelling, microvilli and microbleb formation since 1 hour after monocrotaline administration and during the course, after 5 hours the severity of endothelial cell damage was prominent with presence of fibrin, webs, platelet thrombi and white cell adherence. It was concluded that the monocrotaline primarily induced severe and diffuse endothelial cell damage of pulmonary arteries and laterly added the participation of platelets, which attributed to the pathogenesis of monocrotaline induced pulmonary vascular lesions in relation to pulmonary hypertension.

• YAKHAK HOEJI
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• v.50 no.4
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• pp.293-299
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• 2006

The aim of present study was to investigate the possible influence of Rho-kinase inhibition on the plant-derived estrogen-like compounds-induced arterial relaxation. Agonist- or depolarization-induced vascular smooth muscle contractions involve the activation of Rho-kinase pathway. However there are no reports addressing the question whether this pathway is involved in genistein-or daidzein-induced vascular relaxation in rat aortae precontracted with phenylephrine or thromboxane $A_2$ mimetic U-46619. We hypothesized that Rho-kinase inhibition plays a role in vascular relaxation evoked by genistein or daidzein in rat aortae. Endothelium-intact and denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Genistein concentration-dependently inhibited phenylephrine or thromboxane $A_2-induced$ contraction regardless of endothelial function. Surprisingly, in the agonists-induced contraction, similar results were also observed in aortae treated with daidzein, the inactive congener for protein tyrosine kinase inhibition, suggesting that Rho-kinase might act upstream of tyrosine kinases in phenylephrine-induced contraction. In conclusion, in the agonists-precontracted rat aortae, genistein and daidzein showed similar relaxant response regardless of tyrosine kinase inhibition or endothelial function.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.1
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• pp.17-24
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• 2021

In this study, the potential toxicity of isoprocarb was demonstrated using zebrafish embryos. We treated isoprocarb (0, 29, and 58 mg/L) to the zebrafish embryos for 72 h then, we estimated morphological changes and apoptotic cell numbers. The increasing extent of apoptosis from the anterior to posterior region of developing zebrafish larvae was correlated with toxicity in the overall development process, including growth and normal organ formation. The appearance of abnormalities in the isoprocarb-treated groups in comparison to normal developing zebrafish larvae was verified using quantitative image analysis based on ImageJ software program. The vascular system comprising a complex interconnection of blood vessels was visualized in vessel-fluorescent transgenic zebrafish (fli1:eGFP). The main vasculature was malformed on isoprocarb treatment, and this was also related to cardiac defects. Taken together, normal embryonic development in zebrafish was interrupted owing to the acute toxicity of isoprocarb.

• Journal of Ginseng Research
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• v.47 no.4
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• pp.506-514
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• 2023

Dementia has become one of the most important diseases threatening human health. Alzheimer's disease (AD) and vascular dementia (VaD) have the highest incidence rates among the types of dementia, but until now, therapeutic methods have been limited. Panax ginseng has been used in China for thousands of years to treat dementia, and modern medical studies have found that it contains multiple active components, such as ginsenosides, polysaccharides, amino acids, volatile oils and polyacetylenes, many of which have therapeutic effects in treating AD and VaD. Studies have found that ginsenosides have multitarget therapeutic effects in treating dementia, such as regulation of synaptic plasticity and the cholinergic system, inhibition of Aβ aggravation and tau hyperphosphorylation, anti-neuroinflammation, anti-oxidation effects and anti-apoptosis effects. Other active components of Panax ginseng, such as gintonin, oligosaccharides, polysaccharides and ginseng proteins, also have therapeutic effects on AD and VaD. The effectiveness of ginseng-containing Chinese medicine compounds has also been confirmed by clinical and basic investigations in treating AD and VaD. In this review, we summarized the potential therapeutic effects and related mechanisms of Panax ginseng in treating AD and VaD to provide some examples for further studies.

• Smart Structures and Systems
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• v.16 no.4
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• pp.593-606
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• 2015

This paper presents a novel concept of healing some of the damages in wind turbine blades (WTBs) such as cracks and delamination. This is achieved through an inherent functioning autonomous repairing system. Such wind turbine blades have the benefit of reduced maintenance cost and increased operational period. Previous techniques of developing autonomous healing systems uses hollow glass fibres (HGFs) to deliver repairing fluids to damaged sites. HGFs have been reported with some limitations like, failure to fracture, which undermines their further usage. The self-healing technique described in this paper represents an advancement in the engineering of the delivery mechanism of a self-healing system. It is analogous to the HGF system but without the HGFs, which are replaced by multiple hollow channels created within the composite, inherently in the FRP matrix at fabrication. An in-house fabricated NACA 4412 WTB incorporating this array of network hollow channels was damaged in flexure and then autonomously repaired using the vascular channels. The blade was re-tested under flexure to ascertain the efficiency of the recovered mechanical properties.

• Journal of Ginseng Research
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• v.20 no.4
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• pp.416-430
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• 1996

With the progress of chemical researches in ginseng studies, efforts to elucidate the pharmacological actions of ginseng have been greatly increased. The majority of ginseng reaserches in the past has been performed with crude extracts from ginseng roots to verify scientifically the empirical application of ginseng in men and animals recently. Ginseng reaserches have been done mostly with pure ginsenosides and there has been a shift in focus to the various biochemical pathways. It was demonstvated that ginseng had diverse effects by modulating the second-messenger system, such as cyclic nucleotides. calcium The demonstration in 1987 of the formation of nitric oxide(NO, endothelium-derlled rectating factor) by an enzyme in vascular endothelial cells opened up a new area of biological reaserches of ginseng. It was shown that vascular relaxations induced by glnsenosides are mediated by release of nitric oxide from endothelial cells. According to the literature search from'hledline". There have been 737 original and review articles during the last 30 years. In these review articles, an attempt has been made to summalize some results from some of these published papers. Ginseng has a wide range of phal.macologtcal and therapeutical actions. It acts on the centralral nervous system and cardiovascular system, promotes immune function and metabolism. Possesses anti-stress. Anti-cancer and anti-ageing activities, and so on.o on.