264 research outputs found

    Delay-Optimal Scheduling for Two-Hop Relay Networks with Randomly Varying Connectivity: Join the Shortest Queue-Longest Connected Queue Policy

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    We consider a scheduling problem for a two-hop queueing network where the queues have randomly varying connectivity. Customers arrive at the source queue and are later routed to multiple relay queues. A relay queue can be served only if it is in connected state, and the state changes randomly over time. The source queue and relay queues are served in a time-sharing manner; that is, only one customer can be served at any instant. We propose Join the Shortest Queue-Longest Connected Queue (JSQ-LCQ) policy as follows: (1) if there exist nonempty relay queues in connected state, serve the longest queue among them; (2) if there are no relay queues to serve, route a customer from the source queue to the shortest relay queue. For symmetric systems in which the connectivity has symmetric statistics across the relay queues, we show that JSQ-LCQ is strongly optimal, that is, minimizes the delay in the stochastic ordering sense. We use stochastic coupling and show that the systems under coupling exist in two distinct phases, due to dynamic interactions among source and relay queues. By careful construction of coupling in both phases, we establish the stochastic dominance in delay between JSQ-LCQ and any arbitrary policy

    Antidiabetic Activities of Abutilon indicum (L.) Sweet Are Mediated by Enhancement of Adipocyte Differentiation and Activation of the GLUT1 Promoter

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    Abutilon indicum (L.) Sweet is an Asian phytomedicine traditionally used to treat several disorders, including diabetes mellitus. However, molecular mechanisms supporting the antidiabetic effect of A. indicum L. remain unknown. The aim of this study was to evaluate whether extract of A. indicum L. improves insulin sensitivity. First, we observed the antidiabetic activity of aqueous extract of the entire plant (leaves, twigs and roots) of A. indicum L. on postprandial plasma glucose in diabetic rats. The subsequent experiments revealed that butanol fractions of the extract bind to PPARγ and activate 3T3-L1 differentiation. To measure glucose uptake enhanced by insulin-like activity, we used rat diaphragm incubated with various concentrations of the crude extract and found that the extract enhances glucose consumption in the incubated solution. Our data also indicate that the crude extract and the fractions (water and butanol) did not affect the activity of kinases involved in Akt and GSK-3β pathways; however, the reporter assay showed that the crude extract could activate glucose transporter 1 (GLUT1) promoter activity. These results suggest that the extract from A. indicum L. may be beneficial for reducing insulin resistance through its potency in regulating adipocyte differentiation through PPARγ agonist activity, and increasing glucose utilization via GLUT1

    Clinical Efficacy of Primary Tumor Volume Measurements: Comparison of Different Primary Sites

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    ObjectivesThe purpose of study was to determine the clinical efficacy of primary tumor volume measurements of different primary sites in the oropharynx compared to the oral cavity.MethodsA retrospective analysis of 85 patients with oral cavity or oropharynx cancer. The tumor area was manually outlined from axial magnetic resonance (MR) series. The software calculated the tumor volumes, automatically. The values of the primary tumor volumes were then subdivided into separate groups (≤3,500 mm3, >3,500 mm3).ResultsThe prognostic indicators were the cT and cN (oral cavity); age, primary site, cT, cN, and primary tumor volume (oropharynx) on the univariate analysis. There was no significant prognostic factor for oral cavity cancer on the multivariate analysis. Primary site, cN, and primary tumor volume were independent prognostic indicators for oropharynx cancer by multivariate analysis.ConclusionPrimary tumor volume measurement is a reliable way to stratify outcome, and make up for the weak points in the American Joint Committee on Cancer staging system with oropharynx cancer

    Electrical Loop for 433.92MHz Reader Antenna of RFID Systems

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    A reader antenna for active RFID technology at 433.92MHz, used for cargo container security, is proposed. The proposed antenna consists of two layer radiating elements excited by a single probe simultaneously. An omnidirectional radiation pattern with φ-component of electric field is obtained by an electrical loop with uniform and in-phase current as the radiating source. Measured peak gain is 2.9dBi, and the average gain is 0.92dBi in x-y plane

    Zyflamend, a polyherbal mixture, down regulates class I and class II histone deacetylases and increases p21 levels in castrate-resistant prostate cancer cells

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    Background Zyflamend, a mixture containing extracts of ten herbs, has shown promise in a variety of preclinical cancer models, including prostate cancer. The current experiments were designed to investigate the effects of Zyflamend on the expression of class I and II histone deacetylases, a family of enzymes known to be over expressed in a variety of cancers. Methods CWR22Rv1 cells, a castrate-resistant prostate cancer cell line, were treated with Zyflamend and the expression of class I and II histone deacetylases, along with their downstream target the tumor suppressor gene p21, was investigated. Involvement of p21 was confirmed with siRNA knockdown and over expression experiments. Results Zyflamend down-regulated the expression of all class I and II histone deacetylases where Chinese goldthread and baikal skullcap (two of its components) appear to be primarily responsible for these results. In addition, Zyflamend up regulated the histone acetyl transferase complex CBP/p300, potentially contributing to the increase in histone 3 acetylation. Expression of the tumor suppressor gene p21, a known downstream target of histone deacetylases and CBP/p300, was increased by Zyflamend treatment and the effect on p21 was, in part, mediated through Erk1/2. Knockdown of p21 with siRNA technology attenuated Zyflamend-induced growth inhibition. Over expression of p21 inhibited cell growth and concomitant treatment with Zyflamend enhanced this effect. Conclusions Our results suggest that the extracts of this polyherbal combination increase histone 3 acetylation, inhibit the expression of class I and class II histone deacetylases, increase the activation of CBP/p300 and inhibit cell proliferation, in part, by up regulating p21 expression

    Effects of insertion angle and implant thread type on the fracture properties of orthodontic mini-implants during insertion

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    Objective: To determine the effects of insertion angle (IA) and thread type on the fracture properties of orthodontic mini-implants (OMIs) during insertion. Materials and Methods: A total of 100 OMIs (self-drilling cylindrical; 11 mm in length) were allocated into 10 groups according to thread type (dual or single) and IA (0 degrees, 8 degrees, 13 degrees, 18 degrees, and 23 degrees) (n = 10 per group). The OMIs were placed into artificial materials simulating human tissues: two-layer bone blocks (Sawbones), root (polymethylmethacrylate stick), and periodontal ligament (Imprint-II Garant light-body). Maximum insertion torque (MIT), total insertion energy (TIE), and peak time (PT) were measured and analyzed statistically. Results: There were significant differences in MIT, TIE, and PT among the different IAs and threads (all P<.001). When IA increased, MIT increased in both thread groups. However, TIE and PT did not show significant differences among 0 degrees, 8 degrees, and 13 degrees IAs in the dual-thread group or 8 degrees, 13 degrees, and 18 degrees IAs in the single-thread group. The dual-thread groups showed higher MIT at all IAs, higher TIE at 0 degrees and 23 degrees IAs, and longer PT at a 23 degrees IA than the single-thread groups. In the 0 degrees, 8 degrees, and 13 degrees IA groups, none of the OMIs fractured or became deformed. However, in the 18 degrees IA group, all the OMIs were fractured or deformed. Dual-thread OMIs showed more fracturing than deformation compared to single-thread OMIs (P < .01). In the 23 degrees IA group, all OMIs penetrated the artificial root without fracturing and deformation. Conclusions: When OMIs contact artificial root at a critical contact angle, the deformation or fracture of OMIs can occur at lower MIT values than those of penetration.OAIID:oai:osos.snu.ac.kr:snu2013-01/102/0000004298/8SEQ:8PERF_CD:SNU2013-01EVAL_ITEM_CD:102USER_ID:0000004298ADJUST_YN:YEMP_ID:A072100DEPT_CD:852CITE_RATE:1.184FILENAME:조일식-백승학.pdfDEPT_NM:치의과학과SCOPUS_YN:YCONFIRM:

    Anti-proliferative activity of A. Oxyphylla and its bioactive constituent nootkatone in colorectal cancer cells

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    Background A. oxyphylla extract is known to possess a wide range of pharmacological activites. However, the molecular mechanism of A. oxyphylla and its bioactive compound nootkatone in colorectal cancer is unknown. Methods Our study aims to examine the role of A. oxyphylla and its bioactive compound nootkatone, in tumor suppression using several in vitro assays. Results Both A. oxyphylla extract and nootkatone exhibited antiproliferative activity in colorectal cancer cells. A. oxyphylla displayed antioxidant activity in colorectal cancer cells, likely mediated via induction of HO-1. Furthermore, expression of pro-apoptotic protein NAG-1 and cell proliferative protein cyclin D1 were increased and decreased respectively in the presence of A. oxyphylla. When examined for anticancer activity, nootkatone treatment resulted in the reduction of colony and spheroid formation. Correspondingly, nootkatone also led to increased NAG-1 expression and decreased cyclin D1 expression. The mechanism by which nootkatone suppresses cyclin D1 involves protein level regulation, whereas nootkatone increases NAG-1 expression at the transcriptional level. In addition to having PPARγ binding activity, nootkatone also increases EGR-1 expression which ultimately results in enhanced NAG-1 promoter activity. Conclusion In summary, our findings suggest that nootkatone is an anti-tumorigenic compound harboring antiproliferative and pro-apoptotic activity.This work was supported by the Research Institute for Veterinary Science, and BK21 PLUS Program for Creative Veterinary Science Research Center, Seoul National University, and by a National Research Foundation of Korea (NRF) grant funded by the Korean government (2018R1A2B2002923) to S.J.B. This work was also partially supported by a clinical research grant (NCC1810150) provided by the National Cancer Center to J.R. and S.J.B. The Fig. 7 Nootkatone controls the NAG-1 expression at the transcriptional level. a Nootkatone increases NAG-1 promoter activity. HCT-116 cells were transfected with pNAG-1 − 1086/+ 41 luciferase and pRL-null plasmid. The cells were treated with EtOH or various concentrations of nootkatone for 24 h, and luciferase activity was measured. The y-axis refers to the ratio of firefly luciferase over renillar luciferase activity. The EtOH-treated cells were set as 1.0. Statistical significance was displayed as *p < 0.05, ***p < 0.001 versus EtOH-treated cells. The data represent mean ± SD from three independent experiments. b Three deletion NAG-1 promoter constructs were co-transfected with pRL-null vector into HCT-116 cells. The cells were treated with EtOH or 100 μM of nootkatone for 24 h, and luciferase activity was measured. Fold induction refers to the ratio of luciferase activity in nootkatone-treated cells versus EtOH-treated cells. Statistical significance was displayed as **p < 0.01 and ***p < 0.001 versus EtOH-treated cells. The data represent mean ± SD from three independent experiments. c HCT-116 cells were co-transfected with wild type pNAG-1 − 133/+ 41 in the presence of empty or EGR-1 expression vector. Cells were subsequently treated with 100 μM nootkatone for 24 h. The results are presented as means ± S.D. of three independent transfections. d Western blot of EGR-1 protein in the presence of nootkatone. β-actin was used as loading control. e Luciferase activity of EGR-1 promoter-luciferase construct (pEGR-1260-LUC). The cells were treated with EtOH or nootkatone for 24 h prior to measurement of luciferase activity. Fold induction refers to the ratio of luciferase activity in nootkatone-treated cells compared to EtOH-treated cells. Statistical significance represented as *p < 0.05, ***p < 0.001 versus EtOH-treated cells. n.s. represents not significant. The data represent mean ± SD from four independent experiments Yoo et al. BMC Cancer (2020) 20:881 Page 10 of 12 funding agency did not have any influence in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript

    Expression and regulation of nonsteroidal anti-inflammatory drug–activated gene (NAG-1) in human and mouse tissue

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    AbstractBackground & Aims: Nonsteroidal anti-inflammatory drugs (NSAIDs) induce NSAID-activated gene 1 (NAG-1), which has proapoptotic and antitumorigenic activities. However, NAG-1 expression and its relationship with apoptosis in human and mouse intestinal tract have not been determined. Methods: NAG-1 expression in human and mouse tissue was determined by immunohistochemistry, and apoptosis was estimated by in situ apoptosis detection. Apoptosis in NAG-1 overexpressing HCT-116 cells was examined with flow cytometry after cell sorting by green fluorescence protein. NAG-1 regulation in mouse cells was examined by Northern blot analysis, comparing sulindac-treated and nontreated mice. Results: Apoptosis was higher in NAG-1 overexpressing cells compared with controls. Human NAG-1 protein was localized to the colonic surface epithelium where cells undergo apoptosis, and higher expression was observed in the normal surface epithelium than in most of the tumors. This localization and lower expression in tumors was similar to that in the Min mouse, in which NSAIDs were also shown to regulate the expression of NAG-1 in mouse cells. Sulindac treatment of mice increased the NAG-1 expression in the colon and liver. Conclusions: Based on these results, we propose that NAG-1 acts as a mediator of apoptosis in intestinal cells and may contribute to cancer chemoprevention by NSAIDs.GASTROENTEROLOGY 2002;122:1388-139
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