• Title/Summary/Keyword: Molecular Flow

Search Result 899, Processing Time 0.045 seconds

Comparison for Glomerular Filtration Rate in Gamma Camera Systems Using Dynamic Renal Phantom System (동적신장팬텀시스템 개발에 따른 장비별 사구체여과율의 비교)

  • Kang, Chun Goo;Park, Hoon-Hee;Oh, Shin Hyun;Lee, Han Wool;Kim, Jung Yul;Oh, Joo Yung;Lee, Ju Young;Kim, Jae Sam;Lee, Chang Ho
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.17 no.2
    • /
    • pp.3-9
    • /
    • 2013
  • Purpose: Currently commercially available phantom can reproduce and evaluate only a static situation, the study is incomplete research on phantom and system which is can confirmed functional situation in the kidney by time through dynamic phantom and blood flow velocity, various difference according to the amount of radioactive. Therefore, through this study, it has produced the dynamic kidney phantom to reproduce images through the dynamic flow of the kidney, it desire to evaluate the usefulness of nuclear medicine imaging. Materials and Methods: The production of the kidney phantom was fabricated based on the normal adult kidney, in order to reproduce the dynamic situation based on the fabricated kidney phantom, in this study it was applied the volume pump that can adjust the speed of blood flow, so it can be integrated continuously radioactive isotopes in the kidney by using $^{99m}Tc-pertechnate$. Used the radioactive isotope was supplied through the two pump. It was confirmed the changes according to the infusion rate, radioactive isotopes and the different injection speeds on the left and right, analysis of the acquired images was done by drawn ten times ROI in order to check the reproducibility of each on the front and rear of the kidney and bladder. Results: Under the same conditions infusion rate 40 mL/min fixed to adjust the pressure of the pump when the radiopharmaceuticals between 2-3 minutes in the most integrated in the kidney phantom was excreted inthe bladder. Glomerular filtration rate (GFR), respectively, by each device SYMBIA 1,091 mL/min, FORTE 1,232 mL/min, ARGUS 1,264 mL/min, INFINIA 1,302 mL/min in that there isno statistically significant difference was found, Tmax values and T1/2 values stars from all equipment with no statistically significant difference was found. CV values of the coefficient of variation less than 5% was found to be repeatable, and to 2.67% of the lowest SYMBIA appeared, INFINIA was the highest in the 4.86%. Conclusion: Through this study, the results showed that the dynamic kidney phantom system is able to similarly reproduce renogram in the actual clinical. Especially, the depicted over time for the flow to be excreted through the kidney into the bladder was adequately reproduce, it is expected to be utilized as basic data to check the quality of the dynamic images. In addition, it is considered to help in the field of functional imaging and quality control.

  • PDF

Mechanism Underlying a Proteasome Inhibitor, Lactacystin-Induced Apoptosis on SCC25 Human Tongue Squamous Cell Carcinoma Cells (사람혀편평상피세포암종세포에서 proteasome 억제제인 lactacystin에 의해 유도된 세포자멸사의 기전에 대한 연구)

  • Baek, Chul-Jung;Kim, Gyoo-Cheon;Kim, In-Ryoung;Lee, Seung-Eun;Kwak, Hyun-Ho;Park, Bong-Soo;Tae, Il-Ho;Ko, Myung-Yun;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
    • /
    • v.34 no.3
    • /
    • pp.261-276
    • /
    • 2009
  • Lactacystin, a microbial natural product synthesized by Streptomyces, has been commonly used as a selective proteasome inhibitor in many studies. Proteasome inhibitors is known to be preventing the proliferation of cancer cells in vivo as well as in vitro. Furthermore, proteasome inhibitors, as single or combined with other anticancer agents, are suggested as a new class of potential anticancer agents. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying induction of apoptosis in SCC25 human tongue sqaumous cell carcinoma cell line treated with lactacystin. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingiva fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay respectively. The hoechst staining, hemacolor staining and TUNEL staining were conducted to observe SCC25 cells undergoing apoptosis. SCC25 cells were treated with lactacystin, and Western blotting, immunocytochemistry, confocal microscopy, FAScan flow cytometry, MMP activity, and proteasome activity were performed. Lactacystin treatment of SCC25 cells resulted in a time- and does-dependent decrease of cell viability and a does-dependent inhibition of cell growth, and induced apoptotic cell death. Interestingly, lactacytin remarkably revealed cytotoxicity in SCC25 cells but not normal cells. And tested SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, the decrease of DNA contents, the release of cytochrome c into cytosol, the translocation of AIF and DFF40 (CAD) onto nuclei, the up-regulation of Bax, and the activation of caspase-7, caspase-3, PARP, lamin A/C and DFF45 (ICAD). Flow cytometric analysis revealed that lactacystin resulted in G1 arrest in cell cycle progression which was associated with up-regulation in the protein expression of CDK inhibitors, $p21^{WAF1/CIP1}$ and $p27^{KIP1}$. We presented data indicating that lactacystin induces G1 cell cycle arrest and apoptois via proteasome, mitochondria and caspase pathway in SCC25 cells. Therefore our data provide the possibility that lactacystin could be as a novel therapeutic strategy for human tongue squamous cell carcinoma.

Development of Dynamic Kidney Phantom System and its Evaluation of Usability of Application in Nuclear Medicine (핵의학 동적 신장팬텀시스템 개발 적용의 유용성 평가)

  • Park, Hoon-Hee;Lee, Juyoung;Kim, Sang-Wook;Lyu, Kwang Yeul;Jin, Gye Hwan
    • Journal of radiological science and technology
    • /
    • v.36 no.1
    • /
    • pp.49-55
    • /
    • 2013
  • Currently, commercially available phantom can reproduce and evaluate only a static situation, the study is incomplete research on phantom and system which is can confirmed functional situation in the kidney by time through dynamic phantom and blood flow velocity, various difference according to the amount of radioactive. Therefore, through this study, it has produced the dynamic kidney phantom to reproduce images through the dynamic flow of the kidney, it desires to evaluate the usefulness of nuclear medicine imaging. The production of the kidney phantom was fabricated based on the normal adult kidney, in order to reproduce the dynamic situation based on the fabricated kidney phantom, in this study, it was applied the volume pump that can adjust the speed of blood flow, so it can be integrated continuously radioactive isotopes in the kidney by using $^{99m}Tc$-pertechnate. Used the radioactive isotope was supplied through the two pump. It was confirmed the changes according to the infusion rate, radioactive isotopes and the different injection speeds on the left and right, analysis of the acquired images was done by drawn five times ROI in order to check the reproducibility of each on the front and rear of the kidney and bladder. Depending on the speed of injection, radioisotope was a lot of integrated and emissions up when adjusting the pressure of the pump as 30 stroke, it was the least integrated and emissions up when adjusting as 40 stroke. The integration of the left & right kidney was not reached in the amount of the highest when adjusting as 10 stroke. In the changes according to the amount of the radioactive isotope, 0.6 mCi(22.2 MBq), 0.8 mCi (29.6 MBq)was showed up similar tendency but, in the result of the different injection 0.8 mCi, it was showed up counts close to double of 0.6 mCi. In the result of the differently injection speed of the left & right kidney, as a result of different conditions that injection speed was 20 stroke through left kidney phantom, the injection speed was 30 stroke through right kidney phantom, it was enough difference in the resulting image can be easily distinguished with the naked eye. Through this study, the results showed that the dynamic kidney phantom system is able to similarly reproduce renogram in the actual clinical practice. Especially, the depicted over time for the flow to be excreted through the kidney into the bladder was adequately reproduce, it is expected to be utilized as basic data to check the quality of the dynamic images. In addition, it is considered to help in the field of functional imaging and quality control.

Apoptosis Induction of Human Breast Carcinoma Cells by Ethyl Alcohol Extract of Hizikia fusiforme (Apoptosis 유도에 의한 톳 ethyl alcohol 추출물의 인체 유방암세포 증식 억제)

  • Jung, Sun-Hwa;Hwang, Won-Deuk;Nam, Taek-Jeong;Choi, Yung-Hyun
    • Journal of Life Science
    • /
    • v.19 no.11
    • /
    • pp.1581-1590
    • /
    • 2009
  • Hizikia fusiforme is a kind of brown edible seaweed that mainly grows in the temperate seaside areas of the northwest pacific, including Korea, Japan and China, and has been widely used as a health food for hundreds of years. Recently, H. fusiforme has been known to exert pharmacological activities including antioxidant, antimutagenic and anticoagulant activities. However, the molecular mechanisms of H. fusiforme in malignant cells have not been clearly elucidated yet. In this study, the effects of ethyl alcohol extract of H. fusiforme (EAHF) on the anti-proliferative effects of MDA-MB-231 and MCF-7 human breast cancer cells were investigated. EAHF treatment resulted in a concentration-dependent growth inhibition by including apoptosis in MDA-MB-231 cells and G1 phase arrest in MCF-7 cells, which could be proved by MTT assay, DAPI staining, agarose gel electrophoresis and flow cytometry analysis. In MDA-MB-231 cells, the increase in apoptosis induced by EAHF treatment correlated with up-regulation of pro-apoptotic Bax expression. EAHF treatment induced the proteolytic activation of caspase-3 and caspase-9, and a concomitant inhibition of poly (ADP-ribose) polymerase, $\beta$-catenin, phospholipase-${\gamma}1$ protein and DNA fragmentation factor 45/inhibitor of caspase-activated DNase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of H. fusiforme.

COMPARISON OF FLUX AND RESIDENT CONCENTRATION BREAKTHROUGH CURVES IN STRUCTURED SOIL COLUMNS (구조토양에서의 침출수와 잔존수농도의 파과곡선에 관한 비교연구)

  • Kim, Dong-Ju
    • Journal of Korea Soil Environment Society
    • /
    • v.2 no.2
    • /
    • pp.81-94
    • /
    • 1997
  • In many solute transport studies, either flux or resident concentration has been used. Choice of the concentration mode was dependent on the monitoring device in solute displacement experiments. It has been accepted that no priority exists in the selection of concentration mode in the study of solute transport. It would be questionable, however, to accept the equivalency in the solute transport parameters between flux and resident concentrations in structured soils exhibiting preferential movement of solute. In this study, we investigate how they differ in the monitored breakthrough curves (BTCs) and transport parameters for a given boundary and flow condition by performing solute displacement experiments on a number of undisturbed soil columns. Both flux and resident concentrations have been simultaneously obtained by monitoring the effluent and resistance of the horizontally-positioned TDR probes. Two different solute transport models namely, convection-dispersion equation (CDE) and convective lognormal transfer function (CLT) models, were fitted to the observed breakthrough data in order to quantify the difference between two concentration modes. The study reveals that soil columns having relatively high flux densities exhibited great differences in the degree of peak concentration and travel time of peak between flux and resident concentrations. The peak concentration in flux mode was several times higher than that in resident one. Accordingly, the estimated parameters of flux mode differed greatly from those of resident mode and the difference was more pronounced in CDE than CLT model. Especially in CDE model, the parameters of flux mode were much higher than those of resident mode. This was mainly due to the bypassing of solute through soil macropores and failure of the equilibrium CDE model to adequate description of solute transport in studied soils. In the domain of the relationship between the ratio of hydrodynamic dispersion to molecular diffusion and the peclet number, both concentrations fall on a zone of predominant mechanical dispersion. However, it appears that more molecular diffusion contributes to the solute spreading in the matrix region than the macropore region due to the nonliearity present in the pore water velocity and dispersion coefficient relationship.

  • PDF

Inhibitory Effects of Ethanolic Extracts from Aster glehni on Xanthine Oxidase and Content Determination of Bioactive Components Using HPLC-UV (섬쑥부쟁이 에탄올 추출물의 잔틴산화효소 저해 효능 및 HPLC-UV를 이용한 유효성분의 함량 분석)

  • Kang, Dong Hyeon;Han, Eun Hye;Jin, Changbae;Kim, Hyoung Ja
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.45 no.11
    • /
    • pp.1610-1616
    • /
    • 2016
  • This study aimed to establish an optimal extraction process and high performance liquid chromatography-ultraviolet (HPLC-UV) analytical method for determination of 3,5-dicaffeoylquinic acid (3,5-DCQA) as a part of materials standardization for the development of a xanthine oxidase inhibitor as a health functional food. The quantitative determination method of 3,5-DCQA as a marker compound was optimized by HPLC analysis using a Luna RP-18 column, and the correlation coefficient for the calibration curve showed good linearity of more than 0.9999 using a gradient eluent of water (1% acetic acid) and methanol as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 320 nm. The HPLC-UV method was applied successfully to quantification of the marker compound (3,5-DCQA) in Aster glehni extracts after validation of the method with linearity, accuracy, and precision. Ethanolic extracts of A. glehni (AGEs) were evaluated by reflux extraction at 70 and $80^{\circ}C$ with 30, 50, 70, and 80% ethanol for 3, 4, 5, and 6 h, respectively. Among AGEs, 70% AGE at $70^{\circ}C$ showed the highest content of 3,5-DCQA of $52.59{\pm}3.45mg/100g$ A. glehni. Furthermore, AGEs were analyzed for their inhibitory activities on uric acid production by the xanthine/xanthine oxidase system. The 70% AGE at $70^{\circ}C$ showed the most potent inhibitory activity with $IC_{50}$ values of $77.01{\pm}3.13{\sim}89.96{\pm}3.08{\mu}g/mL$. The results suggest that standardization of 3,5-DCQA in AGEs using HPLC-UV analysis would be an acceptable method for the development of health functional foods.

Antioxidant Effects of Cysteine-containing Peptides of Different Lengths in Human HaCaT Keratinocytes Exposed to Hydrogen Peroxide (과산화수소에 노출된 인간 각질형성세포에서 길이가 다른 시스테인 함유 펩타이드의 항산화 효과)

  • Jae Won Ha;Joon Yong Choi;Yong Chool Boo
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.49 no.3
    • /
    • pp.193-201
    • /
    • 2023
  • Hydrogen peroxide (H2O2) is a type of active oxygen species (ROS) that causes oxidative stress in cells and affects cell growth, proliferation, senescence, and death. The purpose of this study is to find active peptides that attenuate cytotoxicity of H2O2. A positional scanning synthetic tetrapeptide combinatorial library was screened to predict the sequence of potentially active peptides. As a result of comparing the effect of peptide pools on H2O2-induced death of human keratinocytes (HaCaT cells), various active peptide sequences were predicted. Especially, peptides containing cysteine (C) residue were predicted to be active. In follow-up experiments, the cytotoxicity and activity of cysteine-containing peptides of different lengths, such as C-NH2, CC-NH2, CCC-NH2, and CCCC-NH2 were examined. C-NH2 and CC-NH2 showed no significant cytotoxicity up to 1.0 mM, but CCC-NH2, and CCCC-NH2 showed relatively strong cytotoxicity. C-NH2 and CC-NH2 alleviated H2O2-induced cytotoxicity. CC-NH2 was more cytoprotective compared to C-NH2, C, N-acetyl cysteine (NAC), and glutathione (GSH). When intracellular ROS was measured by flow cytometry, H2O2 increased ROS production, and CC-NH2 suppressed ROS production more effectively than C-NH2, and it was as effective as C, NAC, and GSH. This study suggests that CC-NH2 of the cysteine-containing peptides of different lengths has an antioxidant property that safely and effectively alleviates H2O2-induced cytotoxicity and ROS production.

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
    • /
    • v.42 no.1
    • /
    • pp.8-16
    • /
    • 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.

Correlation between Semiquantitative Myocardial Perfusion Score and Absolute Myocardial Blood Flow in $^{13}N-Ammonia$ PET ($^{13}N$-암모니아 PET에서 반정량적 심근관류 점수와 절대적 심근혈류량의 상관관계)

  • Lee, Byeong-Il;Kim, Kye-Hun;Kim, Jung-Young;Kim, Su-Jin;Lee, Jae-Sung;Min, Jung-Joon;Song, Ho-Chun;Bom, Hee-Seung
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.41 no.3
    • /
    • pp.194-200
    • /
    • 2007
  • Purpose: $^{13}N$-ammonia is a well known radiopharmaceutical for the measurement of a myocardial blood flow (MBF) non-invasively using PET-CT. In this study, we investigated a correlation between MBF obtained from dynamic imaging and myocardial perfusion score (MPS) obtained from static imaging for usefulness of cardiac PET study. Methods: Twelve patients (11 males, 1 female, $57.9{\pm}8.6$ years old) with suspicious coronary artery disease underwent PET-CT scan. Dynamic scans (6 min: $5\;sec\;{\times}\;12,\;10\;sec\;{\times}\;6,\;20\;sec\;{\times}\;3,\;and\;30\;sec\;{\times}\;6$) were initiated simultaneously with bolus injection of 11 MBq/kg $^{13}N-ammonia$ to acquire rest and stress image. Gating image was acquired during 13 minutes continuously. Nine-segment model (4 basal walls, 4 mid walls, and apex) was used for a measurement of MBF. Time activity curve of input function and myocardium was extracted from ROI methods in 9 regions for quantification. The MPS were evaluated using quantitative analysis software. To compare between 20-segment model and 9-segment model, 6 basal segments were excluded and averaged segmental scores were used. Results: There are weak correlation between MBF (rest, 0.18-2.38 ml/min/g; stress, 0.40-4.95 ml/min/g) and MPS (rest 22-91%, stress, 14-90%), however the correlation coefficient between corrected MBF and MPS in rest state was higher than stress state (rest r=0.59; stress r=0.80). As a thickening increased, correlation between MBF and MPS also showed good correlation at each segments. Conclusions: Corrected and translated MPS as its characteristics using $^{13}N$-ammonia showed good correlation with absolute MBF measured by dynamic image in this study. Therefore, we showed MPS is one of good indices which reflect MBF. We anticipate PET-CT could be used as useful tool for evaluation of myocardial function in nuclear cardiac study.

Development of Optimum Process for Continuous Hydrolysis of Fish Skin Gelatin Using a Three-Step Recycle Membrane Reactor (재순환 3단계 막반응기를 이용한 어피젤라틴의 연속적 가수분해 최적화 공정 개발)

  • Kim, Se-Kwon;Byun, Hee-Guk
    • Applied Chemistry for Engineering
    • /
    • v.5 no.4
    • /
    • pp.681-697
    • /
    • 1994
  • The enzymatic hydrolysate of gelatin extracted from fish skin was fractionated and recycled through the membrane reactor according to the molecular weight for the purpose of using as functional material. In addition, the enzymatic hydrolysis conditions of gelatin, enzyme stability by membrane and mechanical shear, and effect on the long-term operational stability of the recycle membrane reactor were investigated. Using the pH-drop technique, Alcalase, pronase E and collagenase were identified as the most suitable enzymes for the hydrolysis of fish skin gelatin. The optimum hydrolysis conditions in the 1st-step membrane reactor(1st-SMR) by Alcalase were enzyme concentration 0.2mg/ml, substrate-to-enzyme ratio(S/E) 50(w/w), $50^{\circ}C$, pH 8.0, reaction volume 600ml and flow rate 6.14ml/min. In the 2nd-SMR by pronase E were enzyme concentration 0.3mg/ml, S/E 33(w/w), $50^{\circ}C$, pH 8.0, reaction volume 600ml and flow rate 6.14ml/min. In the case of 3rd-SMR, enzyme concentration 0.1mg/ml, S/E 100(w/w), $37^{\circ}C$, pH 7.5, reaction volume 600ml and flow rate 10ml/min. Decreased enzyme activities by mechanical shear and membrane were 30% and 15% in the 1st-SMR, were 14% and 5% in the 2nd-SMR, and 18% and 8% in the 3rd-SMR, respectively. Under the optimum conditions, the degree of hydrolysis in the 1st, 2nd and 3rd-SMR were 3.5%(Kjeldahl method, 87%), 3.1%(77%) and 2.7%(70%), respectively. The productivity of hydrolysate in the continuous three-step membrane reactor was 430mg per enzyme(mg) for 10 times of volume replacements.

  • PDF