• Title/Summary/Keyword: Flow regulation

Search Result 556, Processing Time 0.026 seconds

Antiproliferative Effect and Apoptotic Mechanism of Extract of Corydalis Yanhusuo on Human Hepatocarcinoma Cells (현호색(玄胡索)이 인체간암세포 증식억제 및 apoptosis 유발에 미치는 영향)

  • Oh, Myun- Taek;Eom, Hyun-Sup;Chi, Gyoo-Yong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.21 no.6
    • /
    • pp.1437-1449
    • /
    • 2007
  • In this study, the effect of extract of Corydalis yanhusuo (ECT) used in Oriental medicine therapy was investigated on the cell growth and apoptosis of HepG2 human hepatoma cells. It was found that ECT could inhibit the cell growth effectively in a dose-dependent manner, which was associated with morphological change and apoptotic cell death such as formation of apoptotic bodies, DNA fragmentation and increased populations of apoptotic-sub G1 phase. And we observed the effects of ECT on loss of mitochondrial membrane potential (MMP), using the JC-1 probe by DNA flow cytometric analysis. Apoptosis of HepG2 cells by ECT was associated with a down-regulation of anti apoptotic Bcl-2 expression, inhibitor of apoptosis proteins (IAPs) expression and proteolytic activation of caspase-3 and caspase-9. However, ECT did not affect the pro-apoptotic Bax expression and activity of caspase-8. ECT treatment also concomitant degradation and /or inhibition of poly (ADP-ribose) polymerase (PARP), phospholipase C-1 ($PLC{\gamma}1$). Furthermore, ECT treatment caused a dose-dependent inhibition of iNOS and cyclooxygenase-2 (Cox-2). Additionally ECT have been implicated in the regulation of telomerase expression. ECT treatment induced the down-regulation of telomerase reverse transcriptase mRNA (hTERT) expression of HepG2 cells. Taken together, these findings suggest that ECT may be a potential chemotherapeutic agent for the control of HepG2 human hepatoma cells.

Quercetin Down-regulates IL-6/STAT-3 Signals to Induce Mitochondrial-mediated Apoptosis in a Non-small-cell Lung-cancer Cell Line, A549

  • Mukherjee, Avinaba;Khuda-Bukhsh, Anisur Rahman
    • Journal of Pharmacopuncture
    • /
    • v.18 no.1
    • /
    • pp.19-26
    • /
    • 2015
  • Objectives: Quercetin, a flavonoid compound, has been reported to induce apoptosis in cancer cells, but its anti-inflammatory effects, which are also closely linked with apoptosis, if any, on non-small-cell lung cancer (NSCLC) have not so far been critically examined. In this study, we tried to determine if quercetin had any demonstrable anti-inflammatory potential, which also could significantly contribute to inducing apoptosis in a NSCLC cell line, A549. Methods: In this context, several assays, including cytotoxicity, flow cytometry and fluorimetry, were done. Gene expression was analyzed by using a western blot analysis. Results: Results revealed that quercetin could induce apoptosis in A549 cells through mitochondrial depolarization by causing an imbalance in B-cell lymphoma 2/Bcl2 Antagonist X (Bcl2/Bax) ratio and by down-regulating the interleukine-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway. An analysis of the data revealed that quercetin could block nuclear factor kappa-light-chain-enhancer of activated B cells (NF-${\kappa}B$) activity at early hours, which might cause a down-regulation of the IL-6 titer, and the IL-6 expression, in turn, could inhibit p-STAT3 expression. Down-regulation of both the STAT3 and the NF-${\kappa}B$ expressions might, therefore, cause down-regulation of Bcl2 activity because both are major upstream effectors of Bcl2. Alteration in Bcl2 responses might result in an imbalance in the Bcl2/Bax ratio, which could ultimately bring about mitochondria mediated apoptosis in A549 cells. Conclusion: Overall, the finding of this study indicates that a quercetin induced anti-inflammatory pathway in A549 cells appeared to make a significant contribution towards induction of apoptosis in NSCLC and, thus, may have a therapeutic use such as a strong apoptosis inducer in cancer cells.

End-to-end Delay Guarantee in IEEE 802.1 TSN with Non-work conserving scheduler (비작업보존 스케줄러를 갖는 IEEE 802.1 TSN에서 단대단 지연시간 보장)

  • Joung, Jinoo
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.18 no.6
    • /
    • pp.121-126
    • /
    • 2018
  • IEEE 802.1 TSN TG is developing standards for end-to-end delay bounds and zero packet loss based on Ethernet technology. We focus on packet forwarding techniques. TSN packet forwarding techniques can be classified into Synchronous and Asynchronous framework. Synchronous approach allocates fixed time period for a class, yet is complex for large networks. Asynchronous approach provides delay guarantee by regulator-scheduler pair, yet is unnecessarily complex, too. We propose network components for TSN Asynchronous architecture, which remove the complexity of maintaining flow state for regulation decisions. Despite such a simplicity, the proposed architecture satisfies the TSN's delay requirements provided the limited high priority traffic's maximum packet length.

The Regulation of FOXP3 Expression by the Treatment of TGF-${\beta}$ and the Modification of DNA Methylation in Lung Cancer Cell Lines

  • Um, Sang-Won;Lee, Sang-Hee;Kim, Ho-Joong;Kwon, O-Jung;Kim, Hang-Rae;Kang, Jae-Seung;Lee, Wang-Jae
    • Tuberculosis and Respiratory Diseases
    • /
    • v.70 no.3
    • /
    • pp.206-217
    • /
    • 2011
  • Background: Transcription factor FOXP3 characterizes the thymically derived regulatory T cells. FOXP3 is expressed by cancer cell itself and FOXP3 expression was induced by TGF-${\beta}$ treatment in pancreatic cancer cell line. However, the expression of FOXP3 expression is not well known in patients with lung cancer. This study was conducted to investigate the expression of FOXP3 in patients with lung cancer and to investigate the regulation of FOXP3 expression by the treatment of TGF-${\beta}$ and DNA methyltransferase inhibitor in lung cancer cell lines. Methods: FOXP3 expression in the tissue of patients with resected non-small cell lung cancer (NSCLC) was evaluated by immunohistochemistry. The regulation of FOXP3 expression was investigated by Western blot and RT-PCR after lung cancer cell lines were stimulated with TGF-${\beta}1$ and TGF-${\beta}2$. The regulation of FOXP3 expression was also investigated by RT-PCR and flow cytometry after lung cancer cell lines were treated with DNA methyltransferase inhibitor (5-AZA-dC). Results: FOXP3 expression was confirmed in 27% of patients with NSCLC. In NCI-H460 cell line, TGF-${\beta}2$ decreased FOXP3 mRNA and protein expressions. In A549 cell line, both TGF-${\beta}1$ and TGF-${\beta}2$ decreased FOXP3 mRNA and protein expressions. 5-AZA-dC increased FOXP3 mRNA expression in NCI-H460 and A549 cell lines. Moreover, 5-AZA-dC increased intracellular FOXP3 protein expression in A549 cell lines. Conclusion: It was shown that FOXP3 is expressed by cancer cell itself in patients with NSCLC. Treatment of TGF-${\beta}2$ and DNA methyltransferase inhibitor seems to be associated with the regulation of FOXP3 expression in lung cancer cell lines.

Induction of Apoptotic Cell Death by Cordycepin, an Active Component of the Fungus Cordyceps militaris, in AGS Human Gastric Cancer Cells (동충하초 유래 cordycepin에 의한 AGS 인체 위암세포의 apoptosis 유발)

  • Lee, Hye Hyeon;Jeong, Jin-Woo;Choi, Yung Hyun
    • Journal of Life Science
    • /
    • v.26 no.7
    • /
    • pp.847-854
    • /
    • 2016
  • Cordycepin, a derivative of the nucleoside adenosine, is one of the active components extracted from fungi of genus Cordyceps, and has been shown to have many pharmacological activities. In this study, we investigated the effects of cordycepin on proliferation and apoptosis of human gastric cancer AGS cells, and its possible mechanism of action. Treatment of cordycepin resulted in significant decrease in cell viability of AGS cells in a concentration-dependent manner. A concentration-dependent apoptotic cell death was also measured by agarose gel electrophoresis and flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in an enhanced expression of tumor necrosis factor-related apoptosis-inducing ligand, death receptor 5 and Fas ligand. Furthermore, up-regulation of pro-apoptotic Bax, and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL expression were also observed in cordycepin-treated AGS cells. These were followed by activation of caspases (caspase-9, -8 and -3), subsequently leading to poly (ADP-ribose) polymerase cleavage. Taken together, these findings indicate that cordycepin induces apoptosis in AGS cells through regulation of multiple apoptotic pathways, including death receptor and mitochondria. Although further mechanical studies are needed, our results revealed that cordycepin can be regarded as a new effective and chemopreventive compound for human gastric cancer treatment.

Effect of Atrial Natriuretic Factor on the Renal Function and Renin Release in Unanesthetized Rabbit (무마취 가토 신장기능에 미치는 Atrial Natriuretic Factor의 영향)

  • Lee, June-K.;Cho, Kyung-W.
    • The Korean Journal of Physiology
    • /
    • v.20 no.1
    • /
    • pp.103-124
    • /
    • 1986
  • Since it has been suggested that atrial receptor may be involved in the mechanism of extracellular volume regulation, it was shown that the granularity of atrial cardiocytes can be changed by water and salt depletion, and that an extract of cardiac atrial tissue, when injected intravenously into anesthetized rats, was shown to cause a large and rapid increase in renal excretion of sodium. Various natriuretic peptides were isolated and synthetized, and the effects were investigated by many workers. Most studies, however, have been carried out under anesthesia and there have teen some controversies over direct effect of the factor on the renal function. Therefore, it was attempted in this study to access the effects of an atrial extract and a synthetic natriuretic factor in unanesthetized rabbits. Intrarenal arterial infusion of atrial extract caused a rapid increase of urinary volume and excretion of sodium. Glomerular filtration rate and renal plasma flow were both increased with no change in filtration fraction. The ventricular extract produced no change in urinary excretion of electrolytes, nor in renal hemodynamics. Intrarenal infusion of synthetic atrial natriuretic factor caused increases of renal excretory rate of sodium, chloride and potassium, and $FE_{Na}$. Glomerular filtration rate, renal plasma flow increased. And free water clearance also increased. Accentuated excretory function correlated well with increased glomerular filtration rate and renal plasma flow during infusion and for 10 minutes following the cessation of the infusion. Renin secretion rate decreased during constant infusion of atrial natriuretic factor. However, no correlation was found with the changes in glomerular filtration rate, renal plasma flow, or urinary excretion of sodium. These results suggest that atrial extract or atrial natriuretic factor induces changes in renal hemodynamics, as in excretion of electrolytes either indirectly through hemodynamic changes or directly by inhibiting tubular reabsorption. At the same time, renin secretory function is affected by the factor possibly through an unknown mechanism.

  • PDF

Numerical Analysis on Flow Characteristics in the Pressurized Air Supply Smoke Control System (급기가압 제연설비의 내부 유동특성에 대한 수치해석)

  • Ko, Gwon-Hyun
    • Fire Science and Engineering
    • /
    • v.31 no.4
    • /
    • pp.52-58
    • /
    • 2017
  • This study investigated the pressure difference distribution and the flow characteristics among room, ancillary room, and stair case by carrying out the numerical simulations on the air flow inside the pressurized air supply smoke control system. Numerical simulations were conducted to analyze pressure and velocity distribution of compartments by pressurized air supply for the air-leakage test facility which was built to measure the effective leakage area. In this study, the leakage of air was considered by locating the narrow slit onto fire door and window of room. Simulated results using this method precisely followed the previous experimental results for the pressure differences between the stair case and ancillary room. Predicted results showed that the local leakage of air rarely affected the overall flow pattern and pressure distribution. Although the average velocity over the door between room and ancillary room satisfied the regulation for fire safety, it was certified the unsafe outflow to ancillary room could be occurred in the local position such as the upper part of the door.

Analysis of the Mediating Effect of Academic Self-efficacy in the Effect of Motivation to Participate of Online Lifelong Education Using YouTube on Learning Flow (유튜브를 활용한 온라인 평생교육의 참여동기가 학습몰입에 미치는 영향에서 학업적 자기효능감의 매개효과 분석)

  • Kim, Tae-Rin
    • The Journal of the Korea Contents Association
    • /
    • v.22 no.5
    • /
    • pp.527-541
    • /
    • 2022
  • This study analyzed the structural relationship between motivation to participate in online lifelong education through YouTube, academic self-efficacy, and learning flow, where learners are rapidly increasing due to the spread of COVID-19. For this study, an online survey was conducted from July 16 to 30, 2021 for adult learners living in the metropolitan area. A total of 428 people participated in the survey, and a total of 409 copies of the results were analyzed, excluding 19 insincere responses. The main analysis results are as follows. First, The fitness of the research model was verified to be suitable for all analysis. Second, as a result of confirming the coefficients and statistical significance of each pathway in the research model, the motivation to participate in YouTube lifelong education was learning flow and academic self-efficacy, and academic self-efficacy also had a positive effect on learning flow. Third, it was confirmed that the effect of participation motivation in YouTube lifelong education on learning flow through academic self-efficacy was a statistically significant partial mediation. This study is meaningful in that it verified the structural relationship analysis between participation motive, academic self-efficacy, and learning flow in online lifelong education using YouTube reflecting the digital transformation of lifelong education due to COVID-19. Reflecting the need for re-regulation of lifelong education formed after COVID-19 and the flow of digital transformation through the research results, we discussed how lifelong education can enhance learners' motivation to participate and strengthen learning flow through academic self-efficacy as a medium.

Cell Cycle Arrest by Treatment of D-Ala2-Leu5-enkephalin in Human Leukemia Cancer U937 Cell. (인체혈구암세포 U937의 D-Ala2-Leu5-enkephalin처리에 의한 세포 주기 억제 효과)

  • Lee, Jun-Hyuk;Choi, Woo-Young;Choi, Yung-Hyun;Choi, Byung-Tae
    • Journal of Life Science
    • /
    • v.19 no.5
    • /
    • pp.620-624
    • /
    • 2009
  • D-Ala2-Leu5-enkephalin (DADLE), a hibernation inducer, can induce hibernation-like state in vivo and in vitro. We treated U937 human leukemia cancer cells with DADLE and investigated its possible effect on transcription and proliferation. Treatment of U937 cells with DADLE resulted in growth inhibition and induction of apoptotic cell death on high-dose as measured by MTT assay and DNA flow cytometer analysis. Bcl-XL, c-IAP-2 and survivin genes especially showed decreases in mRNA levels. DADLE treatment also inhibited the levels of cyclooxygenase (COX)-2 mRNA without alteration of COX-1 expression. DNA flow cytometer analysis revealed that DADLE caused arrest of the cell cycle on low-dose, which was associated with a down-regulation of cyclin E at the transcriptional level. DADLE treatment induced a marked down-regulation of cyclin-dependent kinase (Cdk)-2, -4 and -6. In addition, treatment with DADLE decreased telomere associated genes such as, c-myc and TERT, and increased TEP-1 in U937 cells. These results suggest that DADLE can be an inhibition agent in the cell cycle of the human leukemia cancer U937 cell.

Effects of Supplemental Recombinant Bovine Somatotropin (rbST) and Cooling with Misters and Fans on Renal Function in Relation to Regulation of Body Fluids in Different Stages of Lactation in Crossbred Holstein Cattle

  • Boonsanit, D.;Chanpongsang, S.;Chaiyabutr, N.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.23 no.3
    • /
    • pp.355-365
    • /
    • 2010
  • The aim of this study was to investigate the effect of supplemental recombinant bovine somatotropin (rbST) and cooling with misters and fans on renal function in relation to regulation of body fluids in different stages of lactation in crossbred Holstein cattle. Ten, 87.5% crossbred Holstein cattle were divided into two groups of 5 animals each, housing in a normal shaded barn (NS) and in a shaded barn with a mister-fans cooling system (MF). The experiment in each group was divided into 3 phases, early- (Day 75 postpartum), mid- (Day 135 postpartum), and late stage of lactation (Day 195 postpartum). The pre-treatment study was conducted on the starting day of each stage of lactation and the treatment study was performed after the end of the pre-treatment, during which the animal was injected with 500 mg of rbST (POSILAC) every 14 days for three times. During the study, ambient temperature at the hottest period daily in the MF barn was significantly lower, while relative humidity was higher than that of the NS barn. The temperature humidity index (THI) in both barns ranged from 79-85 throughout the periods of study. Cows in the MF barn showed a lower rectal temperature and respiration rate as compared with cows in the NS barn. The effect of rbST administration increased both rectal temperature and respiration rates of cows housed in either the NS or MF barn. Milk yield significantly increased in cows treated with rbST in all stages of lactation. Increases in mammary blood flow, accompanied by increases of total body water (TBW), extracellular fluid (ECF), blood volume (BV) and plasma volume (PV), were observed in both groups of cows receiving rbST in all stages of lactation. No alterations of renal blood flow and glomerular filtration rate were observed in cows receiving rbST, but decreases in urinary excretion and fractional excretion of sodium, potassium and chloride ions appeared to correlate with reduction in the rate of urine flow and osmolar clearance during rbST administration. These results suggest that the effect of rbST supplementation to cows housed either in NS or MF barns on body fluid volume expansion is attributable to changes in the rate of electrolyte excretion by the kidney. The increased availability of renal tubular reabsorption of sodium, potassium and chloride ions during rbST treatment was a major factor in retaining body water through its colligative properties in exerting formation of an osmotic force mechanism.