• Title/Summary/Keyword: Flow labeling

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Evaluation of Cerebral Blood Flow Using Arterial Spin Labeling in Patients with Chronic Kidney Disease (만성 콩팥병 환자들에서 동맥 스핀 표지 기법을 이용한 뇌 관류상태의 평가)

  • Se Won Oh;Samel Park;Nam-jun Cho;Hyo-Wook Gil;Eun Young Lee;Hyung Geun Oh;Sung-Tae Park
    • Journal of the Korean Society of Radiology
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    • v.81 no.4
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    • pp.912-919
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    • 2020
  • Purpose This study aimed to compare the brain perfusion status of patients with chronic kidney disease to a normal control group to identify any significant differences. Materials and Methods The perfusion state of the brain was measured by MRI using the arterial spin labeling technique in 36 patients undergoing hemodialysis due to chronic kidney disease and 36 normal controls. Images were then analyzed in a voxel-wise manner to detect brain areas showing significant perfusion differences between the two groups. Results Patients with chronic kidney disease showed increased perfusion in the form of large clusters across the right fronto-parieto-temporal lobe and the left parieto-occipital lobe. In addition, perfusion increased in the bilateral thalami, midbrain, pons, and cerebellum (p < 0.01, familywise error corrected). Conclusion Brain perfusion appears to increase in patients with chronic kidney disease compared to normal controls. Uremic toxicity is thought to be the cause of this increase as it can cause damage to the microscopic blood vessels and their surrounding structures.

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.

Object Feature Extraction and Matching for Effective Multiple Vehicles Tracking (효과적인 다중 차량 추적을 위한 객체 특징 추출 및 매칭)

  • Cho, Du-Hyung;Lee, Seok-Lyong
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.11
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    • pp.789-794
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    • 2013
  • A vehicle tracking system makes it possible to induce the vehicle movement path for avoiding traffic congestion and to prevent traffic accidents in advance by recognizing traffic flow, monitoring vehicles, and detecting road accidents. To track the vehicles effectively, those which appear in a sequence of video frames need to identified by extracting the features of each object in the frames. Next, the identical vehicles over the continuous frames need to be recognized through the matching among the objects' feature values. In this paper, we identify objects by binarizing the difference image between a target and a referential image, and the labelling technique. As feature values, we use the center coordinate of the minimum bounding rectangle(MBR) of the identified object and the averages of 1D FFT(fast Fourier transform) coefficients with respect to the horizontal and vertical direction of the MBR. A vehicle is tracked in such a way that the pair of objects that have the highest similarity among objects in two continuous images are regarded as an identical object. The experimental result shows that the proposed method outperforms the existing methods that use geometrical features in tracking accuracy.

Principles and Technical Aspects of Perfusion Magnetic Resonance Imaging (관류 자기공명영상의 원리 및 기술)

  • Jahng, Geon-Ho;Kim, Ho-Sung;Kim, Sun-Mi;Ryu, Chang-Woo
    • Investigative Magnetic Resonance Imaging
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    • v.15 no.2
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    • pp.91-101
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    • 2011
  • Perfusion magnetic resonance imaging (pMRI) is a special technique for evaluation of blood flow. Exogenous pMRI methods which are dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) use an intravenous bolus injection of paramagnetic contrast agent. In contrast, an endogenous pMRM method which is arterial spin labeling (ASL) use diffusible blood in body. In order to scan pMRI in human, technical optimizations are very important according to disease conditions. For examples, DSC is popularly used in patients with acute stroke due to its short scan time, while DSC or DCE provides the various perfusion indices for patients with tumor. ASL is useful for children, women who are expected to be pregnant, and in patients with kidney diseases which are problematic in nephrogenic systemic fibrosis (NSF). Perfusion MRI does not require any injection of radioisotopes. We expect that demand for perfusion MRI will be higher in evaluating drug efficacy and other treatment effects.

Rapid and Accurate Detection of Bacillus anthracis Spores Using Peptide-Quantum Dot Conjugates

  • Park, Tae-Jung;Park, Jong-Pil;Seo, Gwi-Moon;Chai, Young-Gyu;Lee, Sang-Yup
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1713-1719
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    • 2006
  • A method for the simple, rapid, specific, and accurate detection of Bacillus anthracis spores was developed by employing specific capture peptides conjugated with fluorescent quantum dots (QDs). It was possible to distinguish B. anthracis spores from the spores of B. thuringiensis and B. cereus using these peptide-QD conjugates by flow cytometric and confocal laser scanning microscopic analyses. For more convenient high-throughput detection of B. anthracis spores, spectrofluorometric analysis of spore-peptide-QD conjugates was performed. B. anthracis spores could be detected in less than 1 h using this method. In order to avoid any minor yet false-positive signal caused by the presence of B. thuringiensis spores, the B-Negative peptide, which can only bind to B. thuringiensis, conjugated with another type of QD that fluoresces at different wavelength was also developed. In the presence of mixed B. anthracis and B. thuringiensis spores, the BABA peptide conjugated with QD525 and the B-Negative peptide conjugated with QD585 were able to bind to the former and the latter, specifically and respectively, thus allowing the clear detection of B. anthracis spores against B. thuringiensis spores by using two QD-labeling systems. This capture peptide-conjugated QD system should be useful for the detection of B. anthracis spores.

The Effect of Jininwhachul-tang-ga-wasong on the Hepatic Cancer in Mouse by N-Nitrosodiethylamine (진인화철탕가와송(眞人化鐵湯加瓦松)이 N-Nitrosodiethylamine으로 유발된 흰쥐의 간암에 미치는 영향)

  • Lim, Dong-Seok;Choi, Chang-Won
    • The Journal of Internal Korean Medicine
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    • v.29 no.3
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    • pp.582-594
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    • 2008
  • Objective : The purpose of our study was to investigate the effect of JinlnWhaChul-tang-ga-wasong (JIN) on NDEA-induced liver tumorigenesis. Materials and Methods : We investigated the possible protective effects of Jininwhachul-tang-ga-wasong (JIN) as an anticancer against NDEA-induced liver injury in mice. Experimental mice were classified into 3 groups; normal, saline administered group (control group), and JIN extract (0.15g/kg/every other day) administered group (JIN group) after being injected with NDEA over 12 weeks. We examined the state of differentiation of these tumors and the effects of JIN after 6 weeks. To confirm the induction of apoptosis, the cells were analyzed by terminal deorynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, acridine orange staining and flow cytometric analysis. To investigate inhibitory effect on the expression of COX-2 by JIN, we performed COX-2 immunohistochemistry and reverse transcription polymerase chain reaction analysis. Results : Body weights significantly decreased in the control and JIN groups compared with the normal group. The levels of cholesterol, hemoglobin and testosterone decreased in the control compared with the normal group. The level of estradiol significantly increased in the control compared with the normal group. The control group reacted with TUNEL assay more than the normal and JIN groups. Upon naked eye, light and electron microscopic examination, JIN improved the morphological and histopathological changes of the liver caused by NDEA-induced hepatic neoplasm. COX-2 immunoreactivity decreased in the JIN group compared with the control group, mRNA expression of the control group was greater than the normal and JIN groups. Conclusion : these results suggest the possibility that JIN may exert an anti-tumor effect on NDEA-induced liver tumorigenesis.

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Effect of Cisplatin on the Frequency and Immuno-inhibitory Function of Myeloid-derived Suppressor Cells in A375 Melanoma Model

  • Huang, Xiang;Guan, Dan;Shu, Yong-Qian;Liu, Lian-Ke;Ni, Fang
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4329-4333
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    • 2015
  • Background: To investigate the change of frequency and immuno-inhibitory function of myeloid-derived suppressor cells (MDSCs) after treatment of cisplatin (DDP) in A375 human melanoma model. Materials and Methods: BALB/c nude mice were inoculated with A375 cells to establish the human melanoma model and randomly divided into control group given normal saline (NS) and experimental group treated with DDP (5 mg/kg). The percentages of MDSCs in the tumor tissue and peripheral blood after DDP treatment were detected by flow cytometry. The proliferation and interferon-${\gamma}$ (IFN-${\gamma}$) secretion of T cells co-cultured with MDSCs were analyzed through carboxyfluorescein succinimidyl ester (CFSE) labeling assay and enzyme-linked immunospot (ELISPOT) assay, respectively. Results: In A375 human melanoma model, DDP treatment could significantly decrease the percentage of MDSCs in the tumor tissue, but exerted no effect on the level of MDSCs in peripheral blood. Moreover, DDP treatment could attenuate the immuno-inhibitory function of MDSCs. T cells co-cultured with DDP-treated MDSCs could dramatically elevate the proliferation and production of INF-${\gamma}$. Conclusions: DDP can decrease the frequency and attenuate immuno-inhibitory function of MDSCs in A375 melanoma model, suggesting a potential strategy to augment the efficacy of combined immunotherapy.

Apoptotic Effect of Vitisin A from Vitis Amurensis against MES-SA Uterine Cancer Cells (왕머루 포도에서 분리한 Vitisin A의 자궁암주에 대한 자멸사 효과)

  • Lim, Jeong-Han;Lee, Hyo-Jeong;Lee, Eun-Ok;Lee, Hyo-Jung;Kwon, Hee-Young;Shim, Bum-Sang;Ahn, Kyoo-Seok;Kim, Sung-Hoon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.2
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    • pp.290-295
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    • 2008
  • The cytotoxic characteristics of Vitsin A isolated from Vitis amurensis L. were examined in human colorectal, breast, uterine and renal cancer cells. Vitsin A showed good cytotoxicity against various cancer cells with $IC_{50}$ of $1\;{\sim}\;30\;{\mu}M$. Among them, Vitisin A exhibited strongest cytotoxic effect against MES-SA cells with $IC_{50}$ of 1.11 ${\mu}M$ by SRB assay. To verify whether the cytotoxicity of Vitisin A may be associated with apoptosis, TdT-mediated-dUTP Nick-End Labeling (TUNEL) assay and cell cycle analysis were performed in MES-SA cells. Apoptotic bodies were observed in Vitisin A treated MES-SA cells by TUNEL assay. Also, Vitisin A effectively increased the portion of $sub-G_1$ DNA content by flow cytometric analysis. Taken together, these findings suggest that the cytotoxicity of Vitisin A against MES-SA cells is chiefly mediated by apoptosis.

Dual Inhibition of PI3K/Akt/mTOR Pathway and Role of Autophagy in Non-Small Cell Lung Cancer Cells

  • Jeong, Eun-Hui;Choi, Hyeong-Sim;Lee, Tae-Gul;Kim, Hye-Ryoun;Kim, Cheol-Hyeon
    • Tuberculosis and Respiratory Diseases
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    • v.72 no.4
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    • pp.343-351
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    • 2012
  • Background: The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling axis has emerged as a novel target for cancer therapy. Agents that inhibit this pathway are currently under development for lung cancer treatment. In the present study, we have tested whether dual inhibition of PI3K/Akt/mTOR signaling can lead to enahnced antitumor effects. We have also examined the role of autophagy during this process. Methods: We analyzed the combination effect of the mTOR inhibitor, temsirolimus, and the Akt inhibitor, GSK690693, on the survival of NCI-H460 and A549 non-small cell lung cancer cells. Cell proliferation was determined by MTT assay and apoptosis induction was evaluated by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Autophagy induction was also evaluated by acridine orange staining. Changes of apoptosis or autophagy-related proteins were evaluated by western blot analysis. Results: Combination treatment with temsirolimus and GSK690693 caused synergistically increased cell death in NCI-H460 and A549 cells. This was attributable to increased induction of apoptosis. Caspase 3 activation and poly(ADP-ribose) polymerase cleavage accompanied these findings. Autophagy also increased and inhibition of autophagy resulted in increased cell death, suggesting its cytoprotective role during this process. Conclusion: Taken together, our results suggest that the combination of temsirolimus and GSK690693 could be a novel strategy for lung cancer therapy. Inhibition of autophagy could also be a promising method of enhancing the combination effect of these drugs.

Anti-tumor Effect of Amygdalin extracted from Armeniacae Amarum Semen on Human Cervical Cancer Cell ME-180 (행인(杏仁)에서 추출한 Amygdalin의 자궁경부암세포 ME-180에 대한 항암 효과)

  • Choi, Yong-Seok;Kim, Youn-Sub;Kim, Gyung-Jun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.32 no.3
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    • pp.1-12
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    • 2019
  • Objectives: Amygdalin is abundant in the seeds of bitter almond and apricots of the Prunus genus and other rosaceous plants. Amygdalin is known to have antitussive and anticancer activities. Apoptosis, also known as programmed cell death, is an important mechanism in cancer treatment. Methods: In the present study, we investigated whether the aqueous extract of Amygdalin induces apoptotic cell death in ME-180 cervical cancer cells. For this study, 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, terminal deoxynuclotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) assay, 4,6-diamidino-2-phenylindole (DAPI) staining, flow cytometric analysis, DNA fragmentation assay, Western blot, and caspase-3 enzyme assay were performed on ME-180 cervical cancer cells. Results: Through morphological and biochemical analyses, it was demonstrated that ME-180 cells treated with Amygdalin exhibit several apoptotic features. The treatment of Amygdalin increased the Bax expression and caspase-3 enzyme activity and decreased Bcl-2 expression. Here, we have shown that Amygdalin induces apoptotic cell death in ME-180 cervical cancer cells through Bax-dependent caspase-3 activation. These results suggest the possibility that Amygdalin exerts anti-tumor effect on human cervical cancer.