• Title/Summary/Keyword: Vascular change

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Vertical Distribution of Vascular Plants in Jungsanri, Mt. Jiri by Temperature Gradient (지리산 중산리계곡 관속식물의 고도별 온도구배에 따른 수직 분포)

  • Yun, Jong-Hak;Kim, Jung-Hyun;Oh, Kyoung-Hee;Lee, Byoung-Yoon
    • Korean Journal of Environment and Ecology
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    • v.24 no.6
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    • pp.680-707
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    • 2010
  • In order to investigate vertical plant distribution on Jungsanri of Mt. Jirisan by temperature change, vascular plants of fourteen areas with 100-meter-high difference were surveyed from the Jungsan bridge(348 m alt.) to the Jangteumog(1653 m alt.). A total of 440 taxa belonging to 104 families, 287 genera, 385 species, 7 subspecies, 42 varieties, and 6 forma were vegetated on survey areas. Around 700 m high did species diversity of vascular plants decrease rapidly, but foreign species were not found. The Detrended correspondence analysis(DCA) divided distribution of vascular plants into five groups; areas below 500m alt., 500~600m alt., 600~1000m alt., 1000~1200m alt., and areas above 1200m alt.. These results showed that vegetation of vascular plants on investigated areas has high correlation with climate elements of temperature. Vascular plants should be crowded within their own optimal ranges of vegetation. Climate change would result in shift of these distribution ranges, and thus vegetation shift will be happened accordingly.

An Effective Retinal Vessel and Landmark Detection Algorithm in RGB images

  • Jung Eun-Hwa
    • International Journal of Contents
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    • v.2 no.3
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    • pp.27-32
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    • 2006
  • We present an effective algorithm for automatic tracing of retinal vessel structure and vascular landmark extraction of bifurcations and ending points. In this paper we deal with vascular patterns from RGB images for personal identification. Vessel tracing algorithms are of interest in a variety of biometric and medical application such as personal identification, biometrics, and ophthalmic disorders like vessel change detection. However eye surface vasculature tracing in RGB images has many problems which are subject to improper illumination, glare, fade-out, shadow and artifacts arising from reflection, refraction, and dispersion. The proposed algorithm on vascular tracing employs multi-stage processing of ten-layers as followings: Image Acquisition, Image Enhancement by gray scale retinal image enhancement, reducing background artifact and illuminations and removing interlacing minute characteristics of vessels, Vascular Structure Extraction by connecting broken vessels, extracting vascular structure using eight directional information, and extracting retinal vascular structure, and Vascular Landmark Extraction by extracting bifurcations and ending points. The results of automatic retinal vessel extraction using jive different thresholds applied 34 eye images are presented. The results of vasculature tracing algorithm shows that the suggested algorithm can obtain not only robust and accurate vessel tracing but also vascular landmarks according to thresholds.

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VASCULAR EFFECTS OF THE INFERIOR ALVEOLAR NERVE INJECTION OF 2% LIDOCAINE HCI WITH 1:100,000 EPINEPHRINE (백서에서 하치조신경 전달마취후 설배면 혈관반응에 관한 실험연구)

  • Kim, Su-Gwan;Cho, Jae-O
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.3
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    • pp.266-269
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    • 1999
  • This article discusses the vascular change of dorsal surface of tongue following inferior alveolar nerve block of 2% lidocaine HCl with 1:100,000 epinephrine. Twenty-two rats were randomly allocated to three groups: control group; without mandibular nerve block, experimental group 1; 2% lidocaine HCl, experimental group 2; 2% lidocaine HCl plus 1:100,000 epinephrine. The assessments were performed at 1-, 5-, 30-, 60-, 120-minute after inferior alveolar nerve block. Vessel diameters using the micrometer were measured and compared. Results showed that the increase in vascular constriction in group 3 was greater than those in groups 1 and 2. In conclusion, local anesthesia combined with epinephrine assures safer anesthesia for hemostasis.

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Elevational distribution ranges of vascular plant species in the Baekdudaegan mountain range, South Korea

  • Shin, Sookyung;Kim, Jung-Hyun;Dang, Ji-Hee;Seo, In-Soon;Lee, Byoung Yoon
    • Journal of Ecology and Environment
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    • v.45 no.1
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    • pp.62-71
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    • 2021
  • The climate is changing rapidly, and this may pose a major threat to global biodiversity. One of the most distinctive consequences of climate change is the poleward and/or upward shift of species distribution ranges associated with increasing temperatures, resulting in a change of species composition and community structure in the forest ecosystems. The Baekdudaegan mountain range connects most forests from the lowland to the subalpine zone in South Korea and is therefore recognized as one of the most important biodiversity hotspots. This study was conducted to understand the distribution range of vascular plants along elevational gradients through field surveys in the six national parks of the Baekdudaegan mountain range. We identified the upper and lower distribution limits of a total of 873 taxa of vascular plants with 117 families, 418 genera, 793 species, 14 subspecies, 62 varieties, two forms, and two hybrids. A total of 12 conifers were recorded along the elevational gradient. The distribution ranges of Abies koreana, Picea jezoensis, Pinus pumila, and Thuja koraiensis were limited to over 1000 m above sea level. We also identified 21 broad-leaved trees in the subalpine zone. A total of 45 Korean endemic plant species were observed, and of these, 15 taxa (including Aconitum chiisanense and Hanabusaya asiatica) showed a narrow distribution range in the subalpine zone. Our study provides valuable information on the current elevational distribution ranges of vascular plants in the six national parks of South Korea, which could serve as a baseline for vertical shifts under future climate change.

Experimental Study on the Cannabis Fructus on Exercise Capacity and Cognitive Function in Vascular Dementia Rat Model (마자인(麻子仁)이 치매병태모델의 운동과 인지기능에 미치는 실험적 연구)

  • Bae, Kil-Joon;Song, Min-Yeong;Choi, Jin-Bong;Kim, Seon-Jong
    • Journal of Korean Medicine Rehabilitation
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    • v.25 no.1
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    • pp.1-15
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    • 2015
  • Objectives The aim of this study was to investigate the effects of Cannabis Fructus on exercise capacity and cognitive function in chronic hypoperfusion induced vascular dementia rat model. Methods Vascular dementia rat models were induced by chronic cerebral hypoperfusion through bilateral common carotid arteries occlusion (BCCAO). All rats were randomly divided into 4 groups: normal group; control group; CF I group (feeding Cannabis Fructus 100 mg/kg); CF II group (feeding Cannabis Fructus 300 mg/kg). In order to study the effects of oral administration of Cannabis Fructus on vascular dementia rat models, corner turn test, hole board test, radial arm maze test, passive avoidance test were taken and Acetylcholine (ACh) activity, Acetylcholinesterase (AChE) activity, serum of Vascular endothelial growth factor (VEGF) protein level were measured. Also histological findings of the liver, kidney, brain and the change of Tau immunoreactive neurons in hippocampus were observed. Results CF I and CF II showed significant improvement in corner turn test, hole board test, radial arm maze test, passive avoidance test, Acetylcholine (ACh) activity, Acetylcholinesterase (AChE) activity, the serum of Vascular endothelial growth factor (VEGF) protein level and the change of Tau immunoreactive neurons in hippocampus. CF I showed more significant effect than CF II in these tests. However in histological observations of the liver and kidney both CF I and CF II showed glomerular injury and hepatotoxicity. Conclusions These results suggest that Cannabis Fructus was helpful in improving exercise capacity and cognitive function on Chronic hypoperfusion induced Vascular Dementia rats. However Cannabis Fructus affects the liver and kidney, therefore suggest that this is an area for further study.

Delayed Diagnosis of Probable Radiation Induced Spinal Cord Vascular Disorders

  • Won, Young Il;Kim, Chi Heon;Chung, Chun Kee;Yun, Tae Jin
    • Journal of Korean Neurosurgical Society
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    • v.57 no.3
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    • pp.215-218
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    • 2015
  • Occasionally, unexpected neurological deficits occur after lumbar spinal surgery. We report a case of monoparesis after lumbar decompressive surgery. A 63-year-old man, who had undergone decompression of L4-5 for spinal stenosis 4 days previously in the other hospital, visted the emergency department with progressive weakness in the left leg and hypoesthesia below sensory level T7 on the right side. He had been cured of lung cancer with chemotherapy and radiation therapy 10 years previously, but detailed information of radiotherapy was not available. Whole spine magnetic resonance (MR) imaging showed fatty marrow change from T1 to T8, most likely due to previous irradiation. The T2-weighted MR image showed a high-signal T4-5 spinal cord lesion surrounded by a low signal rim, and the T1-weighted MR image showed focal high signal intensity with focal enhancement. The radiological diagnosis was vascular disorders with suspicious bleeding. Surgical removal was refused by the patient. With rehabilitation, the patient could walk independently without assistance 2 months later. Considering radiation induced change at thoracic vertebrae, vascular disorders may be induced by irradiation. If the spinal cord was previously irradiated, radiation induced vascular disorders needs to be considered.

A Vascular Characteristic Index of Blood Pressure Variation using the Pulse Wave Signal

  • Kim, Gi-Ryon;Jung, Dong-Keun;Ye, Soo-Young;Jeon, Gye-Rok
    • Transactions on Electrical and Electronic Materials
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    • v.9 no.5
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    • pp.213-219
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    • 2008
  • Pulse waves continuously change with respect to the characteristics and status of the cardiovascular system and in relation to the blood pressure (BP) and the pulse wave velocity (PWV). Monitoring the vascular condition by analyzing the variations in pulse waveforms has been used to diagnose vascular disorders and in drug treatment of arteriosclerosis and peripheral circulatory obstruction. In this paper, we investigated the vascular characteristic index with regard to the BP and classified by pulse wave signals. The pressure pulse wave and photoplethysmography (PPG) were measured simultaneously while subjects exercised, producing changes in the BP, to analyze the variation in the vascular characteristic index. We investigated the correlation between the BP and vascular characteristic index with regard to the classification methods of the pulse wave. The reflection index (RI) and vascular stiffness index were correlated with the diastolic BP, but no correlation was found between these parameters and the systolic BP. These results suggest the possibility of estimating BP through simple measurements of pulse waves.

The Effects of Fowler's Position Change on Back Pain and Discomfort of the Patients Following Percutaneous Coronary Intervention (경피적 관상동맥중재술 후 반좌위 체위변경이 환자의 요통과 불편감에 미치는 효과)

  • Nam, So-Young;ChoiKwon, Smi
    • Perspectives in Nursing Science
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    • v.7 no.1
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    • pp.55-64
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    • 2010
  • Purpose: The purpose of this study was to examine the effects of position change from supine to Fowler's on back pain and discomfort in patients who remained on bed rest after undergoing PCIs with a vascular closure device. Methods: Data was collected from 35 inpatients who were hospitalized in coronary-care unit to perform PCIs with a vascular closure device at S hospital in Seoul from December, 2006 to May, 2007. Back pain, discomfort, presence and grade of bleeding and hematoma from femoral arterial puncture site and blood pressure/pulse rate were measured prior to, 10 minutes, 1 hour and 2 hours after position change. Data was analyzed with descriptive statistics, $x^2$ tests and t-tests using SPSS/WIN 12.0 for Windows program. The level of significance (${\alpha}$) was set at 0.05 for this study. Results: We found that there was no significant difference in back pain and discomfort in 10 minutes after position change between the two groups. However, the experimental group reported significantly less back pain and discomfort than the control group in 1 hour (p<.01, respectively) and 2 hour (p<.01, respectively) after position change. There was no significant difference in the presence and grade of bleeding and hematoma at the puncture site, blood pressure, and pulse rate in 10 minutes, 1hour and 2hours after position change between the two groups. Conclusion: Fowler's position change after PCIs in, therefore, safe and effective method of reducing back pain and physical discomfort without causing additional bleeding and changes in blood pressure and pulse rate.

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Change of Pulmonary Artery Hemodynamics and Pulmonary Vascular Resistance in Experimental Pulmonary Embolism (실험적 급성 폐색전증에서 폐동맥혈역학 및 폐혈관저항의 변화)

  • Chung, Hee-Soon;Lee, Jae-Ho;Kim, Cheol-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.913-922
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    • 1995
  • Background: When we define the pressure of pulmonary vasculature in which a recruitment of blood flow occurs as $P_I$ and the proportion of change in pulmonary artery to that in cardiac output as IR and then we compare PI and IR with pulmonary vascular resistance, we would find some problems in pulmonary vascular resistance. In other words, it is the theory that, IR should be increased mainly in pulmonary embolism in which decreases the cross sectional area of pulmonary vasculature. But there are many contradictory reports resulted from various researches and the fact is known widely that any difference exists between PVR and PI, IR. For this reason, the purpose of this study is to observe how PI and IR change at the time of the outbreak and during treatment of the pulmonary embolism, and to find out the meaning of these new indicators and the difference from the pulmonary vascular resistance used generally when we subdivide the pulmonary vascular resistance into PI and IR. Method: After making AV fistula in experimental dog, we controlled cardiac output at the intervals of 15 minute in case of three kinds(all AV fistula are obstructed, only one of fistula is open and all of fistula is open), and after evoking massive pulmonary embolism with radioactive autologous blood clots, we measured the mean pulmonary artery pressure, and calculated PI and IR. We observed the pattern of change in PI and IR, without giving the control group any specific treatment and with injecting intravenously rtPA in the Group 1 and Group 2 at the dose of 1mg per kg, for 15 minutes fot the former and 3 hours for the latter. Result: 1) Pulmonary vascular resistance showed a change similar to that of pulmonary artery pressure and in all three group, PVR increased significantly, but group 1 and group 2 showed tendency that PVR keeps on decreasing after treatment, and the rate of decrease in group 1 is more rapid than group 2 significantly. 2) Both intersection(PI) and degree(IR) are proved statistically significant, in view of the straight line relationship between cardiac output and pulmonary artery pressure, calculated by minimal regression method. 3) PI changed similarly to pulmonary vascular resistance, while in the IR which is theoretically more similar to PVR, there was no significant difference or change after rtPA infusion. Conclusion: In the pulmonary embolism, Both change in IR which means real resistance of pulmonary vasculature and PI which was developed due to secondary vasoconstriction by pulmonary embolism are reflected same time.

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Vascular Morphometric Changes During Tumor Growth and Chemotherapy in a Murine Mammary Tumor Model Using OCT Angiography: a Preliminary Study

  • Kim, Hoonsup;Eom, Tae Joong;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.3 no.1
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    • pp.54-65
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    • 2019
  • To develop a biomarker predicting tumor treatment efficacy is helpful to reduce time, medical expenditure, and efforts in oncology therapy. In clinics, microvessel density using immunohistochemistry has been proposed as an indicator that correlates with both tumor size and metastasis of cancer. In the preclinical study, we hypothesized that vascular morphometrics using optical coherence tomography angiography (OCTA) could be potential indicators to estimate the treatment efficacy of breast cancer. To verify this hypothesis, a 13762-MAT-B-III rat breast tumor was grown in a dorsal skinfold window chamber which was applied to a nude mouse, and the change in vascular morphology was longitudinally monitored during tumor growth and metronomic cyclophosphamide treatment. Based on the daily OCTA maximum intensity projection map, multiple vessel parameters (vessel skeleton density, vessel diameter index, fractal dimension, and lacunarity) were compared with the tumor size in no tumor, treated tumor, and untreated tumor cases. Although each case has only one animal, we found that the vessel skeleton density (VSD), vessel diameter index and fractal dimension (FD) tended to be positively correlated with tumor size while lacunarity showed a partially negative correlation. Moreover, we observed that the changes in the VSD and FD are prior to the morphological change of the tumor. This feasibility study would be helpful in evaluating the tumor vascular response to treatment in preclinical settings.