• Title/Summary/Keyword: Attenuation Index

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Normal Control Study of Cerebral Blood Flow by Tc-99m HM-PAO SPECT ($^{99m}TC-HMPAO$ SPECT를 이용한 정상인 국소뇌혈류의 정량적 분석)

  • Moon, Dae-Hyuk;Lee, Bum-Woo;Lee, Kyung-Han;Choi, Yoon-Ho;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Yoon, Byung-Woo;Lee, Nam-Soo;Roh, Jae-Kyu;Myung, Ho-Jin;Koong, Sung-Soo
    • The Korean Journal of Nuclear Medicine
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    • v.23 no.2
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    • pp.155-163
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    • 1989
  • Regional cerebral perfusion was evaluated in 15 normal controls by single photon emission computed tomography using $^{99m}Tc$ HM-PAO. For quantitative analysis, 13 pairs of homologous region of interest (ROI) were drawn on three transverse slices matching the vascular territories and cerebral cortices, and normal values of 3 semiqunatitative indices including 'Right to left ratio'(R/L ratio), 'Regional index'(RI), and 'Region to cerebellum ratio'(R/cbll ratio) were calculated. Mean values of R/L ratios of homotogous regions were ranged from 0.985 to 1.023, and mean ${\pm}2$ s.d. of all regions did not exceed 11% of mean. Significant difference of RIs (mean count per voxel of a ROI/mean count per voxel of total ROIs) between regions were found (p<0.001) with highest values in occipital cortex and cerebellum. After attenuation correction, RIs in deep gray, cranial portion of anterior cerebral artery and vascular territories in the 2nd slice increased significantly (p < 0.05-0.001), but vise versa in other ROIs. Region to cerebellum ratios also showed regional difference similar to RIs.

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Anti-nociceptive and Anti-inflammatory Effects of Gami-cheongyulsaseub-tang in Arthritic Model (관절염 모델에서 가미청열사습탕(加味淸熱瀉濕湯)의 진통 및 소염 효과에 관한 연구)

  • Kim, Il-Hyun;Lee, Ha-Il;Lee, Se-Won;Kwon, Young-Mi;Song, Yung-Sun
    • Journal of Korean Medicine Rehabilitation
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    • v.25 no.1
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    • pp.27-44
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    • 2015
  • Objectives This study was carried out to find the effects of Gami-cheongyulsaseub-tang (hereinafter referred to GCST) on the inhibition of zymosan-induced pain in rats and collagen II-induced arthritis (CIA) in DBA/1J mouse. Methods As an acute inflammatory pain model, peripheral inflammation was induced by intraplantar injection of zymosan into the right hind paw in rats and then the hyperalgesia and pain regulating factors in spinal cord were analyzed. As a chronic inflammation model, the mixture of collagen II and complete Freund's adjuvant was treated into mice to establish rheumatoid arthritis and then body weight, thickness of hind paw, pathological change of spleen, immunological rheumatoid factor (IgG1, IgG2a, IgG2b, IgM and anti-collagen II), pro-inflammatory cytokines, and bone injury were analyzed. Results In the acute inflammatory pain model, GCST significantly inhibited the thermal and mechanical hyperalgesia and the pain regulating factors, including Fos, CD11b, PKA and PKC, in the spinal cord with a dose-dependent manner. In the chronic rheumatoid arthritis model, GCST administration decreased arthritic index and paw edema as compared with CIA control group. In particular, GCST reduced significantly the serum levels of total IgG2a, IgG2b, IgM, and specific anti-collagen II, but not total IgG1. GCST also resulted in the attenuation of bone injury and spleen enlargement/adhesion in CIA mice. Moreover, the secretion of pro-inflammatory cytokines TNF-${\alpha}$ and IL-$1{\beta}$ in CIA mice was significantly reduced by GCST in a dose-dependent manner. Conclusions Comparison of the results in this study showed that GCST had anti-nociceptive and immunomodulatory effects. These data imply that GCST can be used as an effective drug for not only rheumatoid arthritic pain but also other auto-immune diseases.

Evaluation of the Low Tube Voltage in the Computed Tomography Scan Technique using a Low Concentration Contrast Agent (저농도 조영제를 사용한 CT검사에서 저관전압 기법에 따른 유용성 평가)

  • Jung, Kang-Kyo;Cho, Pyong-Kon
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.71-79
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    • 2016
  • The purpose of this study is computed tomography contrast agent at low concentrations and low tube voltage technique to evaluate the usefulness on the phantom image. By varying the degree of mixture by the contrast medium concentration it was inserted in phantom. It was taken by changing the tube voltage and tube current step by step, and to evaluate the dose and the CT value obtained from the phantom image. As a result, low-contrast, low tube voltage(300 mgI/ml, 100 kV) was reduced by an average 21%(CTDIvol; computed tomography dose indexvol) more standard condition(350 mgI/ml, 120 kV). SNR was increased at all depths of the phantom, respectively 1:10 and 1:20(by diluting a contrast agent and normal saline) 12.2(26%) 6.2(17%). CNR was increased at all depths of the phantom, respectively 1:10 and 1:20(by diluting a contrast agent and normal saline) 11.5(32%), 6.3(26%). Research work on the CT scan is necessary in a variety of studies on the low contrast concentration and low tube voltage techniques for dose reduction and reducing of side effects the contrast agent.

A study on the standard for determining airborne sound insulation performance of sound barrier panels (방음판의 음향투과손실 측정규격에 관한 연구)

  • Oh, Yang Ki
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.3
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    • pp.302-311
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    • 2022
  • Sound barrier walls are one of the most effective alternatives for reducing environmental noise on roads and railways in the city center. The insertion loss of the sound barrier against road traffic noise is the sum of the sound transmission loss, sound absorption loss, and sound energy reduction due to the diffraction attenuation of the sound barrier. The sound transmission loss of the sound barrier is one of the important factors that determine the insertion loss of the sound barrier and is a basic indicator that determines the performance of the sound barrier. Nevertheless, there is not a separate standard in Korea for measuring the acoustic transmission loss of sound barrier panels. There are only a few conditions in KS F 4770 series that stipulates on the general material of sound barrier panels. This thesis examines the necessity of the acoustic transmission loss measurement and evaluation standards of sound barrier walls, and seeks a measurement method in a free sound field (anechoic chamber) sound receiving room considering the characteristics of sound barrier walls installed in external spaces, unlike indoor building materials. In addition, a single number evaluation method using a reference spectrum was proposed so that the sound insulation effect according to various installation places such as roadside or railroad side can be easily displayed.

Role of soy lecithin combined with soy isoflavone on cerebral blood flow in rats of cognitive impairment and the primary screening of its optimum combination

  • Hongrui Li;Xianyun Wang;Xiaoying Li;Xueyang Zhou;Xuan Wang;Tiantian Li;Rong Xiao;Yuandi Xi
    • Nutrition Research and Practice
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    • v.17 no.2
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    • pp.371-385
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    • 2023
  • BACKGROUND/OBJECTIVES: Soy isoflavone (SIF) and soy lecithin (SL) have beneficial effects on many chronic diseases, including neurodegenerative diseases. Regretfully, there is little evidence to show the combined effects of these soy extractives on the impairment of cognition and abnormal cerebral blood flow (CBF). This study examined the optimal combination dose of SIF + SL to provide evidence for improving CBF and protecting cerebrovascular endothelial cells. MATERIALS/METHODS: In vivo study, SIF50 + SL40, SIF50 + SL80 and SIF50 + SL160 groups were obtained. Morris water maze, laser speckle contrast imaging (LSCI), and hematoxylin-eosin staining were used to detect learning and memory impairment, CBF, and damage to the cerebrovascular tissue in rat. The 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the oxidized glutathione (GSSG) were detected. The anti-oxidative damage index of superoxide dismutase (SOD) and glutathione (GSH) in the serum of an animal model was also tested. In vitro study, an immortalized mouse brain endothelial cell line (bEND.3 cells) was used to confirm the cerebrovascular endothelial cell protection of SIF + SL. In this study, 50 µM of Gen were used, while the 25, 50, or 100 µM of SL for different incubation times were selected first. The intracellular levels of 8-OHdG, SOD, GSH, and GSSG were also detected in the cells. RESULTS: In vivo study, SIF + SL could increase the target crossing times significantly and shorten the total swimming distance of rats. The CBF in the rats of the SIF50 + SL40 group and SIF50 + SL160 group was enhanced. Pathological changes, such as attenuation of the endothelium in cerebral vessels were much less in the SIF50 + SL40 group and SIF50 + SL160 group. The 8-OHdG was reduced in the SIF50 + SL40 group. The GSSG showed a significant decrease in all SIF + SL pretreatment groups, but the GSH showed an opposite result. SOD was upregulated by SIF + SL pretreatment. Different combinations of Genistein (Gen)+SL, the secondary proof of health benefits found in vivo study, showed they have effective anti-oxidation and less side reaction on protecting cerebrovascular endothelial cell. SIF50 + SL40 in rats experiment and Gen50 + SL25 in cell test were the optimum joint doses on alleviating cognitive impairment and regulating CBF through protecting cerebrovascular tissue by its antioxidant activity. CONCLUSIONS: SIF+SL could significantly prevent cognitive defect induced by β-Amyloid through regulating CBF. This kind of effect might be attributed to its antioxidant activity on protecting cerebral vessels.

Prognostic Value of Sarcopenia and Myosteatosis in Patients with Resectable Pancreatic Ductal Adenocarcinoma

  • Dong Wook Kim;Hyemin Ahn;Kyung Won Kim;Seung Soo Lee;Hwa Jung Kim;Yousun Ko;Taeyong Park;Jeongjin Lee
    • Korean Journal of Radiology
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    • v.23 no.11
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    • pp.1055-1066
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    • 2022
  • Objective: The clinical relevance of myosteatosis has not been well evaluated in patients with pancreatic ductal adenocarcinoma (PDAC), although sarcopenia has been extensively researched. Therefore, we evaluated the prognostic value of muscle quality, including myosteatosis, in patients with resectable PDAC treated surgically. Materials and Methods: We retrospectively evaluated 347 patients with resectable PDAC who underwent curative surgery (mean age ± standard deviation, 63.6 ± 9.6 years; 202 male). Automatic muscle segmentation was performed on preoperative computed tomography (CT) images using an artificial intelligence program. A single axial image of the portal phase at the inferior endplate level of the L3 vertebra was used for analysis in each patient. Sarcopenia was evaluated using the skeletal muscle index, calculated as the skeletal muscle area (SMA) divided by the height squared. The mean SMA attenuation was used to evaluate myosteatosis. Diagnostic cutoff values for sarcopenia and myosteatosis were devised using the Contal and O'Quigley methods, and patients were classified according to normal (nMT), sarcopenic (sMT), myosteatotic (mMT), or combined (cMT) muscle quality types. Multivariable Cox regression analyses were conducted to assess the effects of muscle type on the overall survival (OS) and recurrence-free survival (RFS) after surgery. Results: Eighty-four (24.2%), 73 (21.0%), 75 (21.6%), and 115 (33.1%) patients were classified as having nMT, sMT, mMT, and cMT, respectively. Compared to nMT, mMT and cMT were significantly associated with poorer OS, with hazard ratios (HRs) of 1.49 (95% confidence interval, 1.00-2.22) and 1.68 (1.16-2.43), respectively, while sMT was not (HR of 1.40 [0.94-2.10]). Only mMT was significantly associated with poorer RFS, with an HR of 1.59 (1.07-2.35), while sMT and cMT were not. Conclusion: Myosteatosis was associated with poor OS and RFS in patients with resectable PDAC who underwent curative surgery.

Investigation of Drought Propagation and Damage Characteristics Using Meteorological and Hydrological Drought Indices (기상학적 및 수문학적 가뭄지수를 활용한 가뭄 전이 및 피해 특성 분석)

  • Kim, Ji Eun;Son, Ho-Jun;Kim, Taesik;Kim, Won-Beom;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.3
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    • pp.291-302
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    • 2024
  • Sustained meteorological drought can lead to hydrological drought, known as drought propagation. The propagated droughts cause more damage to the region than the non-propagated droughts. Recent studies on drought propagation have focused on identifying the lag time using correlation analysis. There is a lack of studies comparing damage patterns between propagated and non-propagated droughts. In this study, the overlap and pooling propagation between meteorological and hydrological droughts were analyzed using drought indices in Chungcheong Province to identify drought propagation, and the propagation characteristics such as pooling, attenuation, lag and extension were analyzed. The results showed that although Chungju-si experienced a meteorological drought in 2010, no damage was caused by the drought. However, a meteorological drought in 2017 and 2018 propagated into a hydrological drought of longer duration but less severity, resulting in drought-affected damage. Similarly, Cheongyang-gun experienced a meteorological drought in 2017, but no damage was reported from the drought. However, in the neighboring county of Buyeo-gun, a meteorological drought with a similar magnitude propagated to a hydrological drought during the same period, resulting in drought-affected damage. The overall results indicated that the damage from propagated drought events was more severe than the non-propagated drought events, and these results can be used as basic data for establishing drought response policies suitable for the region.

The Serial Change of Cerebral Hemodynamics by Vascular Territory after Extracranial-Intracranial Bypass Surgery in Patients with Atherosclerosis of Cerebral Arteries (죽상 동맥 경화성 뇌혈관 폐색 환자에서의 두개외강-내강 우회로술 후의 혈관 영역별 연속 혈류역학 변화)

  • Hong, Il-Ki;Kim, Jae-Seung;Ahn, Jae-Sung;Kwon, Sun-Uck;Im, Ki-Chun;Lee, Jai-Hyuen;Moon, Dae-Hyuk
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.1
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    • pp.8-16
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    • 2008
  • Purpose: To assess the effect of extracranial-intracranial (EC-IC) bypass surgery on hemodynamic improvement, we evaluated serial regional cerebral hemodynamic change of the middle cerebral artery (MCA) in symptomatic patients with atherosclerotic occlusion of the internal carotid artery (ICA) or MCA using $^{99m}Tc$-ECD acetazolamide stress brain perfusion SPECT (Acetazolamide SPECT). Materials and Methods: The patients who had suffered a recent stroke with atherosclerotic ICA or MCA occlusion underwent EC-IC bypass surgery and Acetazolamide SPECT at 1 week before and three to six months after surgery. For image analysis, attenuation corrected images were spatially normalized to SPECT templates with SPM2. Anatomical automated labeling was applied to calculate mean counts of each Volume-Of-Interest (VOI). Seven VOIs of bilateral frontal, parietal, temporal regions of the MCA territory and the ipsilateral cerebellum were defined. Using mean counts of 7 VOIs, cerebral perfusion index and perfusion reserve index were calculated. Results: Seventeen patients (M:F =12:5, mean age $53{\pm}2yr$) were finally included in the analysis. The cerebral blood flow of the parietal region increased at 1 week (p = 0.003) and decreased to the preoperative level at 3-6 months (p = 0.003). The cerebrovascular reserve of the frontal and parietal regions increased significantly at 1 week after surgery (p<0.01) and improved further at 3-6 months. Conclusion: Cerebrovascular reserve of the MCA territory was significantly improved at early postoperative period after EC-IC bypass and kept improved state during long-term follow-up, although cerebral blood flow did not significantly improved. Therefore, cerebrovascular reserve may be a good indicator of postoperative hemodynamic improvement resulted from bypass effect.

A Study on Skin Status with Acoustic Measurements of Skin Friction Noise (피부 마찰 소음 측정을 통한 피부 상태 연구)

  • Chang, Yun Hee;Seo, Dae Hoon;Koh, A Rum;Kim, Sun Young;Lim, Jun Man;Han, Jong Seup;Lee, Sang Hwa;Park, Sun Gyoo;Kim, Yang Han
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.2
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    • pp.103-109
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    • 2016
  • Efficacy of cosmetics has been mainly evaluated by qualitative and quantitative methods based on visual sense, tactile sense and skin structure until now. In this study, we suggested a novel evaluation method for skin status based on sound; measuring and analyzing the rubbing noise generated by applying cosmetics. First, the rubbing noise was measured at a close range by a high-sensitivity microphone in anechoic environment, and the noises were analyzed by 1/3 octave band analysis in frequency-domain. Three conditions, 1) before washing, 2) after washing and 3) after application of cosmetics, were compared. As a result, sound pressure level (SPL) of rubbing noise after washing was larger than that of before washing, and the SPL of rubbing noise after cosmetic application was the smallest. Furthermore, the energy of rubbing noise after application was higher than that of the before and after washing conditions in a low frequency band (lower than 2 kHz region). Conversely, the energy of rubbing noise after application was much lower than the others in a high-frequency band (upper than 2 kHz region). This change of energy distribution was described as a balloon-skin model. High SPL in the low frequency region after the cosmetic applications was due to the increase of "flexibility index", while SPL in the high frequency region significantly decreased because of the attenuation which is related to "softness index". Therefore, we developed two indices based on the spectrum-energy difference for evaluating skin conditions. This proposed method and indices were verified via skin flexibility and roughness measurement using cutometer and primos respectively. These results suggest that acoustic measurement of skin friction noise may be a new skin status evaluation method.

Biological Effect of Vaccinium uliginosum L. on STZ-induced Diabetes and Lipid Metabolism in Rats (들쭉이 약물에 의해 유도된 당뇨 및 지질대사에 미치는 생리활성 효과)

  • Han, Eun-Kyung;Kwon, Hyuck-Se;Shin, Se-Gye;Choi, Yoon-Hee;Kang, Il-Jun;Chung, Cha-Kwon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.12
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    • pp.1727-1733
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    • 2012
  • This study was conducted to investigate the effects of Vaccinium uliginosum L. (bilberry) on chemically induced diabetes and hypercholesterolemia. Sprague Dawley (SD) rats were divided into six groups, control (CON), bilberry added group (CBB), streptozotocin (STZ)-induced diabetic group (STZ), STZ and bilberry added group (SBB), high fat fed group (HFF) and high fat and bilberry added group (HFB). Diabetes was chemically induced by intravenous injection of 45 mg/kg body weight STZ in citrate buffer (pH 4.5). Serum triglycerides decreased significantly (p<0.05) in the STZ group that was fed bilberry. Additionally, the athrogenic index (AI) decreased significantly (p<0.05) when compared to the STZ group, while the liver triglycerides tended to decrease in the STZ group. HDL-cholesterol also increased significantly in response to bilberry. When compared to the STZ group, steady attenuation of the blood glucose level was observed upon fasting, 15 min, 30 min, 60 min and 120 min after oral glucose administration. The blood glucose level in the bilberry fed group decreased by 24% when compared to STZ group, while the superoxide dismutase (SOD) became significantly higher (p<0.05) in the STZ group when compared to the CON group. Overall, the results of this study suggest that bilberry stimulates lipid metabolism in both the serum and liver and has a positive effect on glucose metabolism in chemically induced diabetic rats.