WorldWideScience

Sample records for chemosensitivity test-guided systemic

  1. A case of advanced intrahepatic cholangiocarcinoma successfully treated with chemosensitivity test-guided systemic chemotherapy

    Institute of Scientific and Technical Information of China (English)

    Kazumichi Abe; Takeru Wakatsuki; Fumiko Katsushima; Kyoko Monoe; Yukiko Kanno; Atsushi Takahashi; Junko Yokokawa; Hiromasa Ohira

    2009-01-01

    Intrahepatic cholangiocarcinoma (ICC) is a relatively rare and highly fatal neoplasm that arises from the biliary epithelium. Prognosis is generally poor and survival is limited to a few months. Here we present a case of advanced ICC successfully treated by chemosensitivity test-guided systemic chemotherapy combining S-1 and cisplatin (CDDP). A 65-year-old woman with a liver tumor was referred to our hospital on November 21, 2007. Abdominal ultrasonography and computed tomography (CT) showed low-density masses of 50 and 15 mm in diameter, respectively in segment Ⅷ of the liver and in the enlarged lymph node in the para-aorta. Ultrasonography-guided fine needle biopsy diagnosed the tumors as ICC. Since the patient was inoperable for lymph node metastasis, she underwent systemic chemotherapy with gemcitabine. Six months after initiation of chemotherapy, CT revealed ICC progression in the liver and pleural dissemination with pleural effusion. The patient was admitted to our hospital for anticancer drug sensitivity testing on June 9, 2008. Based on the sensitivity test results, we elected to administer systemic chemotherapy combining S-1 and CDDP. Two months into the second chemotherapy treatment, CT revealed a reduction of the tumors in the liver and lymph node and a decrease in pleural effusion.After eight cycles of the second chemotherapy, 17 mo after ICC diagnosis, she is alive and well with no sign of recurrence. We conclude that chemosensitivity testing may effectively determine the appropriate chemotherapy regimen for advanced ICC.

  2. Assessment of pancreatic carcinoma cell chemosensitivity using a three-dimensional culture system

    Institute of Scientific and Technical Information of China (English)

    LIAO Quan; HU Ya; ZHAO Yu-pei; ZHOU Tao; ZHANG Qiang

    2010-01-01

    Background Monolayer cell culture models are the traditional culture models used for in vitro research of pancreatic carcinoma chemosensitivity. However, these models neglect the interactions between tumor cells and the impact of the tumor microenvironment. Such tumor cell monolayers poorly mimic the solid tumor microenvironment. The present study aimed to investigate the chemosensitivity characteristics of pancreatic cancer cells in a three-dimensional culture system by analyzing the differences in drug sensitivity between a scattered cell culture model and a multicellular spheroid culture model.Methods Three pancreatic cancer cell lines (SW1990, ASPC-1 and PCT-3) were cultured in three-dimensional collagen gels as well as in traditional two-dimensional monolayers. The chemosensitivities of the pancreatic carcinoma cells to 5-fluorouracil (5-FU), gemcitabine, and oxaliplatin in vitro were detected by both the Cell Counting Kit-8 test and the collagen gel droplet-embedded culture drug-sensitivity test.Results In the two-dimensional culture model, differences in the chemosensitivities of the cloned pancreatic carcinoma cells and scattered cells existed for some concentrations of 5-FU, gemcitabine and oxaliplatin. In the three-dimensional culture model, there were significant differences in the chemosensitivities of the pancreatic cancer cells between the scattered cells and multicellular spheroids (P <0.05).Conclusion Pancreatic carcinoma cells exhibit multicellular resistance in three-dimensional cultures.

  3. A systems analysis of the chemosensitivity of breast cancer cells to the polyamine analogue PG-11047

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Wen-Lin; Das, Debopriya; Ziyad, Safiyyah; Bhattacharya, Sanchita; Gibb, William J.; Heiser, Laura M.; Sadanandam, Anguraj; Fontenay, Gerald V.; Hu, Zhi; Wang, Nicholas J.; Bayani, Nora; Feiler, Heidi S.; Neve, Richard M.; Wyrobek, Andrew J.; Spellman, Paul T.; Marton, Laurence J.; Gray, Joe W.

    2009-11-14

    Polyamines regulate important cellular functions and polyamine dysregulation frequently occurs in cancer. The objective of this study was to use a systems approach to study the relative effects of PG-11047, a polyamine analogue, across breast cancer cells derived from different patients and to identify genetic markers associated with differential cytotoxicity. A panel of 48 breast cell lines that mirror many transcriptional and genomic features present in primary human breast tumours were used to study the antiproliferative activity of PG-11047. Sensitive cell lines were further examined for cell cycle distribution and apoptotic response. Cell line responses, quantified by the GI50 (dose required for 50% relative growth inhibition) were correlated with the omic profiles of the cell lines to identify markers that predict response and cellular functions associated with drug sensitivity. The concentrations of PG-11047 needed to inhibit growth of members of the panel of breast cell lines varied over a wide range, with basal-like cell lines being inhibited at lower concentrations than the luminal cell lines. Sensitive cell lines showed a significant decrease in S phase fraction at doses that produced little apoptosis. Correlation of the GI50 values with the omic profiles of the cell lines identified genomic, transcriptional and proteomic variables associated with response. A 13-gene transcriptional marker set was developed as a predictor of response to PG-11047 that warrants clinical evaluation. Analyses of the pathways, networks and genes associated with response to PG-11047 suggest that response may be influenced by interferon signaling and differential inhibition of aspects of motility and epithelial to mesenchymal transition.

  4. Inhibition of Bcl-2 expression by a novel tumor-specific RNA interference system increases chemosensitivity to 5-fluorouracil in Hela cells

    Institute of Scientific and Technical Information of China (English)

    Sheng-lin HUANG; Yi WU; Hai YU; Ping ZHANG; Xing-qian ZHANG; Lei YING; Han-fang ZHAO

    2006-01-01

    Aim: RNA interference (RNAi) has been proposed as a potential treatment for cancer, but the lack of cellular targets limits its use in cancer gene therapy. No current technology has achieved direct tumor-specific gene silencing using RNAi.In the present study we attempt to develop a tumor-specific RNAi system using the human telomerase reverse transcriptase (hTERT) promoter; furthermore, we analyzed its inhibitive effect on Bcl-2 expression. Methods: The vectors containing a small hairpin RNA (shRNA) to target exogenous reporters [firefly luciferase and enhanced green fluorescent protein (EGFP)] and endogenous gene (Bcl-2)were constructed. Luciferase expression was determined by dual luciferase assay.Reverse transcription-polymerase chain reaction (RT-PCR), fluorescence microscopy and fluorescence-activated cell sorting (FACS) were used to measure EGFP expression. Inhibition of Bcl-2 was evaluated by RT-PCR and Western blotting.Cell proliferation and viability were measured by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. FACS was used to analyze the cell cycle distribution profile. Results: We showed that with the hTERT promoter directly driving shRNA transcription, expression of the exogenous reporters (LUC and EGFP) in tumor cells, but not normal cells, was specifically inhibited in vitro. The hTERT promoter-driven shRNA also depressed the expression of Bcl-2. Inhibition of Bcl-2 did not affect cell proliferation, but increased the chemosensitivity of HeLa cells to 5-fluorouracil. Conclusion: The present study describes an efficient RNAi system for gene silencing that is specific to tumor cells using the hTERT promoter. Suppression of Bcl-2 by using this system sensitized HeLa cells to 5-fluorouracil. This system may be useful for RNAi therapy.

  5. Ethical hacking and penetration testing guide

    CERN Document Server

    Baloch, Rafay

    2014-01-01

    Requiring no prior hacking experience, Ethical Hacking and Penetration Testing Guide supplies a complete introduction to the steps required to complete a penetration test, or ethical hack, from beginning to end. You will learn how to properly utilize and interpret the results of modern-day hacking tools, which are required to complete a penetration test. The book covers a wide range of tools, including Backtrack Linux, Google reconnaissance, MetaGooFil, dig, Nmap, Nessus, Metasploit, Fast Track Autopwn, Netcat, and Hacker Defender rootkit. Supplying a simple and clean explanation of how to effectively utilize these tools, it details a four-step methodology for conducting an effective penetration test or hack.Providing an accessible introduction to penetration testing and hacking, the book supplies you with a fundamental understanding of offensive security. After completing the book you will be prepared to take on in-depth and advanced topics in hacking and penetration testing. The book walks you through each ...

  6. Heterogeneity of chemosensitivity in esophagealcancer using ATP-tumor chemosensitivity assay

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang LING; Zhi-xing YANG; Jian YIN; Wei-min MAO; Chun-jian QI; Xiao-xiao LU; Li-juan QIAN; Lin-hui GU; Zhi-guo ZHENG; Qiang ZHAO; Shi WANG; Xian-hua FANG

    2012-01-01

    Current chemotherapy for esophageal cancer is conducted on the basis of empirical information from clinical trials,which fails to take into account the known heterogeneity of chemosensitivity between patients.This study was aimed to demonstrate the degree of heterogeneity of chemosensitivity in esophageal cancers.Methods:A total of 42 esophageal cancer specimens were collected.The heterogeneity of chemosensitivity in esophageal cancer specimens was examined using an ex vivo ATP-tumor chemosensitivity assay (ATP-TCA).Results:Thirty eight specimens produced evaluable results (90.5%).The most active single agent tested was nedaplatin,to which 28.9% of samples were sensitive.Combinations of chemotherapy agents exhibited much higher sensitivity:cisplatin+paclitaxel was sensitive in 16 of 38 (42.1%) of samples,while nedaplatin+paclitaxel was more effective,which was sensitive in 20 of 38 cases (52.6%).Conclusion:There was a marked heterogeneity of chemosensitivity in esophageal cancer.Chemosensitivity testing may provide apractical method for testing new regimens before clinical trials in esophageal cancer patients.

  7. Resistance gene expression determines the in vitro chemosensitivity of non-small cell lung cancer (NSCLC

    Directory of Open Access Journals (Sweden)

    Amer Khalid

    2009-08-01

    Full Text Available Abstract Background NSCLC exhibits considerable heterogeneity in its sensitivity to chemotherapy and similar heterogeneity is noted in vitro in a variety of model systems. This study has tested the hypothesis that the molecular basis of the observed in vitro chemosensitivity of NSCLC lies within the known resistance mechanisms inherent to these patients' tumors. Methods The chemosensitivity of a series of 49 NSCLC tumors was assessed using the ATP-based tumor chemosensitivity assay (ATP-TCA and compared with quantitative expression of resistance genes measured by RT-PCR in a Taqman Array™ following extraction of RNA from formalin-fixed paraffin-embedded (FFPE tissue. Results There was considerable heterogeneity between tumors within the ATP-TCA, and while this showed no direct correlation with individual gene expression, there was strong correlation of multi-gene signatures for many of the single agents and combinations tested. For instance, docetaxel activity showed some dependence on the expression of drug pumps, while cisplatin activity showed some dependence on DNA repair enzyme expression. Activity of both drugs was influenced more strongly still by the expression of anti- and pro-apoptotic genes by the tumor for both docetaxel and cisplatin. The doublet combinations of cisplatin with gemcitabine and cisplatin with docetaxel showed gene expression signatures incorporating resistance mechanisms for both agents. Conclusion Genes predicted to be involved in known mechanisms drug sensitivity and resistance correlate well with in vitro chemosensitivity and may allow the definition of predictive signatures to guide individualized chemotherapy in lung cancer.

  8. Chemosensitization by antisense oligonucleotides targeting MDM2.

    Science.gov (United States)

    Bianco, Roberto; Ciardiello, Fortunato; Tortora, Giampaolo

    2005-02-01

    The MDM2 oncogene is overexpressed in many human cancers, including sarcomas, certain hematologic malignancies, and breast, colon and prostate cancers. The p53-MDM2 interaction pathway has been suggested as a novel target for cancer therapy. To that end, several strategies have been explored, including the use of small polypeptides targeted to the MDM2-p53 binding domain, anti-MDM2 antisense oligonucleotides, and natural agents. Different generations of anti-human-MDM2 oligonucleotides have been tested in in vitro and in vivo human cancer models, revealing specific inhibition of MDM2 expression and significant antitumor activity. Use of antisense oligos potentiated the effects of growth inhibition, p53 activation and p21 induction by several chemotherapeutic agents. Increased therapeutic effectiveness of chemotherapeutic drugs in human cancer cell lines carrying p53 mutations or deletions have shown the ability of MDM2 inhibitors to act as chemosensitizers in various types of tumors through both p53-dependent and p53-independent mechanisms. Inhibiting MDM2 appears to also have a role in radiation therapy for human cancer, regardless of p53 status, providing a rationale for the development of a new class of radiosensitizers. Moreover, MDM2 antisense oligonucleotides potentiate the effect of epidermal growth factor receptor (EGFR) inhibitors by affecting in vitro and in vivo proliferation, apoptosis and protein expression in hormone-refractory and hormone-dependent human prostate cancer cells. These data support the development, among other MDM2 inhibitors, of anti-MDM2 antisense oligonucleotides as a novel class of anticancer agents, and suggest a potentially relevant role for the oligonucleotides when integrated with conventional treatments and/or other signaling inhibitors in novel therapeutic strategies.

  9. Targeting Tumor Ubiquitin-Proteasome Pathway with Polyphenols for Chemosensitization

    OpenAIRE

    Shen, Min; Chan, Tak Hang; Dou, Q. Ping

    2012-01-01

    The development of tumor drug resistance is one of the biggest obstacles on the way to achieve a favorable outcome of chemotherapy. Among various strategies that have been explored to overcome drug resistance, the combination of current chemotherapy with plant polyphenols as a chemosensitizer has emerged as a promising one. Plant polyphenols are a group of phytochemicals characterized by the presence of more than one phenolic group. Mechanistic studies suggest that polyphenols have multiple i...

  10. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    Directory of Open Access Journals (Sweden)

    Vitaly eDzhavakhiya

    2012-03-01

    Full Text Available A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or chemosensitization. Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole combined with 4-hydroxybenzaldehyde (4-HBA, 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of A. alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of F. sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend.

  11. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    Science.gov (United States)

    Dzhavakhiya, Vitaly; Shcherbakova, Larisa; Semina, Yulia; Zhemchuzhina, Natalia; Campbell, Bruce

    2012-01-01

    A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or "chemosensitization." Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin) combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole) applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole) combined with 4-hydroxybenzaldehyde (4-HBA), 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of Alternaria alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of Fusarium sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend.

  12. Gefitinib ('Iressa', ZD1839) may restore chemosensitivity in NSCLC patients?

    Science.gov (United States)

    Fujiwara, Keiichi; Kiura, Katsuyuki; Gemba, Kenichi; Ogata, Yoshiko; Hotta, Katsuyuki; Kishino, Daizo; Tabata, Masahiro; Ueoka, Hiroshi; Tanimoto, Mitsune

    2005-01-01

    Gefitinib ('Iressa, ZD1839) has promising antitumor activity in non-small cell lung cancer (NSCLC). However, patients with advanced NSCLC have few treatment options available if they are refractory to gefitinib. We describe four cases of patients with advanced NSCLC who previously responded to gefitinib and obtained significant tumor regression through retreatment with other cytotoxic agents. Gefitinib might restore chemosensitivity to previously chemorefractory patients.

  13. Apollon modulates chemosensitivity in human esophageal squamous cell carcinoma.

    Science.gov (United States)

    Zhang, Si; Tang, Wenqing; Weng, Shuqiang; Liu, Xijun; Rao, Benqiang; Gu, Jianxin; Chen, She; Wang, Qun; Shen, Xizhong; Xue, Ruyi; Dong, Ling

    2014-08-30

    Patients with esophageal squamous cell carcinoma (ESCC) are often diagnosed with advanced diseases that respond poorly to chemotherapy. Here we reported that Apollon, a membrane-associated inhibitor of apoptosis protein, was overexpressed in ESCC cell lines and clinical ESCC tissues, and Apollon overexpression clinically correlated with poor response to chemotherapy (P = 0.001), and short overall survival (P = 0.021). Apollon knockdown increased cisplatin/docetaxel-induced apoptosis, mitochondrial dysfunction and cytochrome c release in two ESCC cell lines. Apollon knockdown potentiated cisplatin/docetaxel-induced long-term cell growth inhibition, and enhanced chemosensitivity of ESCC cells to cisplatin/docetaxel in xenograft tumor models. Apollon knockdown also enhanced cisplatin/docetaxel-induced activation of caspase-8 (extrinsic pathway) and caspase-9 (intrinsic pathway) in ESCC cells and xenograft tumor models. Mechanism studies revealed that the effect of Apollon on chemosensitivity is mainly mediated by Smac. Apollon expression strongly and negatively correlated with Smac expression in clinical ESCC tissues (P = 0.001). Apollon targeted Smac for degradation in ESCC cells. The effect of Apollon on chemosensitivity was reversed by Smac knockdown in ESCC cells. Taken together, our data show association of Apollon expression with chemotherapeutic response in ESCC, and provide a strong rationale for combining Apollon antagonism with chemotherapy to treat ESCC.

  14. The chemosensitizer cyclosporin A enhances the toxic side-effects of doxorubicin in the rat

    NARCIS (Netherlands)

    W. van de Vrie (Wim); A.M. Jonker (Ard Mieke); R.L. Marquet (Richard); A.M.M. Eggermont (Alexander)

    1994-01-01

    textabstractthe feasibility of using chemosensitizers in the circumvention of P-glycoprotein-mediated multidrug resistance has been shown in many studies. We recently reported on the chemosensitizing effect of cyclosporin A (CsA) on doxorubicin in a rat solid tumour model. Using the same experimenta

  15. Chemosensitive nanocomposite for conductometric detection of hydrazine and NADH

    Energy Technology Data Exchange (ETDEWEB)

    Lange, Ulrich [Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93047 Regensburg (Germany); Mirsky, Vladimir M., E-mail: vmirsky@hs-lausitz.d [Department of Nanobiotechnology, Lausitz University of Applied Sciences, 01968 Senftenberg (Germany)

    2011-04-01

    A new chemosensitive material based on palladium nanoparticles and PEDOT-PSS is described. The composite was characterized by transmission electron microscopy, cyclic voltammetry and in situ resistance measurements. The material was applied for conductometric detection of hydrazine and NADH. Upon exposure to these analytes PEDOT is reduced leading to an increase in its conductance. This process is catalyzed by palladium. A model for description of the potential dependence of polymer conductivity was suggested, tested and applied for the development of new calibration procedure of chemiresistors based on electroactive polymers.

  16. In vitro chemosensitivity tests on xenografted human melanomas.

    OpenAIRE

    1980-01-01

    An in vitro chemosensitivity test has been applied to malignant melanoma cells from 5 patients. The tumour cells were first grown as xenografts in immune-suppressed mice, so that the results of the in vitro test could be compared with precise measurements of the sensitivity of the melanoma cells when exposed to chemotherapeutic drugs in vivo in the mouse. The in vitro assay involved exposing the tumour cells to each of 8 drugs, after which cell survival was determined by colony assay in soft ...

  17. Inter-experiment variation and dependence on culture conditions in assaying the chemosensitivity of human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Roed, H; Christensen, I B; Vindeløv, L L

    1987-01-01

    by a logarithmic function. Even after correction for lack of proportionality the two assay systems provided significantly different dose-response curves. The stability of the chemosensitivity was tested after 25-30 weeks continuous in vitro culture or prolonged storage in liquid nitrogen. One cell line underwent...... line, dose-response curves obtained on several cell lines in different assay systems should be used in the evaluation of new drugs....

  18. Chemosensitizers of the multixenobiotic resistance in amorphous aggregates (marine snow): etiology of mass killing on the benthos in the Northern Adriatic?

    Science.gov (United States)

    Müller, W E; Riemer, S; Kurelec, B; Smodlaka, N; Puskaric, S; Jagic, B; Müller-Niklas, G; Queric, N V

    1998-12-01

    Periodically appearing amorphous aggregates, `marine snow', are formed in the sea and if settled as mats on the sea bottom cause death of benthic metazoans. Especially those animals are killed which are sessile filter feeders, e.g. sponges, mussels, or Anthozoa. The etiology of the toxic principle(s) is not yet well understood. Gel-like marine snow aggregates occurred in the Northern Adriatic during summer 1997. Samples of these aggregates were collected during the period July to September and the outer as well as the inner zones were analyzed for (i) cell toxicity, and (ii) chemosensitizing activity of the multixenobiotic resistance (MXR) mechanism. Organic extracts were prepared and cell toxicity was determined using mouse lymphoma cells. The experiments revealed that the major activity is seen in the center of the mats of the gel-like aggregates; a growth inhibitory activity of up to 54% (correlated to 5 ml of snow sample) was determined. The same extracts were used to determine the inhibition of the P-glycoprotein (Pgp) extrusion pump which confers the multixenobiotic resistance. The analyses were performed with cells from the sponge Suberites domuncula and with gills from the clam Corbicula fluminea in situ. Both systems have been shown to express the Pgp extrusion pump. The data show that extracts from the outer zone of the gel-like aggregate samples display pronounced inhibitory activity on the MXR extrusion pump and hence act as chemosensitizers by reversing the MXP property. These findings indicate that gel-like aggregates contain compounds in the outer zone, chemosensitizer of the Pgp extrusion pump, which lower the level of protection of metazoan animals towards dissolved compounds in their surrounding milieu, and in the center toxic compounds which are-very likely-even in the absence of chemosensitizers hazardous for the invertebrates.

  19. Central respiratory chemosensitivity and cerebrovascular CO2 reactivity: a rebreathing demonstration illustrating integrative human physiology.

    Science.gov (United States)

    MacKay, Christina M; Skow, Rachel J; Tymko, Michael M; Boulet, Lindsey M; Davenport, Margie H; Steinback, Craig D; Ainslie, Philip N; Lemieux, Chantelle C M; Day, Trevor A

    2016-03-01

    One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations have the added benefit of being able to show multiple organ system integration. Many research techniques can also serve as effective demonstrations of integrative human physiology. The "Duffin" hyperoxic rebreathing test is often used in research settings as a test of central respiratory chemosensitivity and cerebrovascular reactivity to CO2. We aimed to demonstrate the utility of the hyperoxic rebreathing test for both respiratory and cerebrovascular responses to increases in CO2 and illustrate the integration of the respiratory and cerebrovascular systems. In the present article, methods such as spirometry, respiratory gas analysis, and transcranial Doppler ultrasound are described, and raw data traces can be adopted for discussion in a tutorial setting. If educators have these instruments available, instructions on how to carry out the test are provided so students can collect their own data. In either case, data analysis and quantification are discussed, including principles of linear regression, calculation of slope, the coefficient of determination (R(2)), and differences between plotting absolute versus normalized data. Using the hyperoxic rebreathing test as a demonstration of the complex interaction and integration between the respiratory and cerebrovascular systems provides senior undergraduate, graduate, and medical students with an advanced understanding of the integrative nature of human physiology.

  20. [Study of chemosensitivity in patients believed to have sleep apnea syndrome].

    Science.gov (United States)

    Costes, F; Court-Fortune, I; Fournel, P; Vergnon, J M; Emonot, A; Geyssant, A

    1995-01-01

    We performed polysomnography and measured hypoxic ventilatory (HVR), hypercapnic ventilatory responses (HCVR) in 42 patients (60 +/- 11 years) with obesity and a clinical suspicion of sleep apnea syndrome (SAS) in order to determine whether an altered chemosensitivity was associated with SAS. The apnea/hypopnea index was 38 +/- 20 events per hour of sleep in 28 patients (SAS+ group) and less than 10 in the 14 others (SAS- group). The 2 groups differed only by a lower waking PaO2 in SAS+ as compared to SAS- (71.0 +/- 9 vs 77.4 +/- 8 mmHg, p obesity and SAS there is no difference in chemosensitivity due to the presence of sleep apnea and that CPAP therapy does not alter these measurements. These results suggest no direct effect of SAS on chemosensitivity in the population studied.

  1. In Vitro Chemosensitivity Testing of Primary and Recurrent Breast Carcinomas and Its Clinical Significance

    Institute of Scientific and Technical Information of China (English)

    Zhi LI; Haiping SONG; Wenshan HE; Yuan TIAN; Tao HUANG

    2008-01-01

    In this study, in vitro chemosensitivity testing was conducted on primary cultured breast cancer cells from 96 patients with breast cancer, and the results showed that the cells from a few patients with primary breast cancer developed multidrug resistance (MDR) prior to the first chemotherapy exposure. All the cells from the recurrent cancer patients had MDR. The findings suggested that patients having MDR would benefit from high-dose chemotherapy (HDC) regimens. In vitro chemosensitivity screening, which was aimed at improving the therapeutic efficacy and minimizing side effects, helps in choosing individualized treatment for breast cancer.

  2. 1-phenyl-2-decanoylamino-3-morpholino-1-propanol chemosensitizes neuroblastoma cells for taxol and vincristine

    NARCIS (Netherlands)

    Sietsma, H; Veldman, Robert; Ausema, B; Nijhof, W; Kamps, W; Vellenga, E; Kok, JW

    2000-01-01

    In this study, we show that an inhibitor of glycosphingolipid biosynthesis, D,L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), increases the chemosensitivity of neuroblastoma tumor cells for Taxol and vincristine. At noneffective low doses of Taxol or vincristine, the addition of a n

  3. Predictive value of early F-18-fluoro-deoxyglucose positron emission tomography in chemosensitive relapsed lymphoma

    NARCIS (Netherlands)

    Schot, B; van Imhoff, G; Pruim, J; Sluiter, W; Vaalburg, W; Vellenga, E

    2003-01-01

    F-18-fluoro-deoxyglucose (FDG) positron emission tomography (PET) might be a better tool than computerized tomography (CT) in predicting long-term treatment outcome in patients with relapsed chemosensitive lymphoma who are candidates for autologous stem cell transplantation (ASCT). We studied patien

  4. Use of chemosensitization to overcome fludioxonil-resistance in Penicillium expansum

    Science.gov (United States)

    Resistance in two mutant strains of Penicillium expansum to the fungicide fludioxonil was overcome by co-application of natural phenolic chemosensitizing agents that targeted various elements of the oxidative stress-response pathway. Fludioxonil resistance in these strains resulted from cell-linked ...

  5. Knockdown of UbcH10 Enhances the Chemosensitivity of Dual Drug Resistant Breast Cancer Cells to Epirubicin and Docetaxel

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2015-03-01

    Full Text Available Breast cancer is one of the most common and lethal cancers in women. As a hub gene involved in a diversity of tumors, the ubiquitin-conjugating enzyme H10 (UbcH10, may also play some roles in the genesis and development of breast cancer. In the current study, we found that the expression of UbcH10 was up-regulated in some breast cancer tissues and five cell lines. We established a dual drug resistant cell line MCF-7/EPB (epirubicin/TXT (docetaxel and a lentiviral system expressing UbcH10 shRNA to investigate the effects of UbcH10 knockdown on the chemosensitivity of MCF-7/EPB/TXT cells to epirubicin and docetaxel. The knockdown of UbcH10 inhibited the proliferation of both MCF-7 and MCF-7/EPB/TXT cells, due to the G1 phase arrest in cell cycle. Furthermore, UbcH10 knockdown increased the sensitivity of MCF-7/EPB/TXT cells to epirubicin and docetaxel and promoted the apoptosis induced by these two drugs. Protein detection showed that, in addition to inhibiting the expression of Ki67 and cyclin D1, UbcH10 RNAi also impaired the increased BCL-2 and MDR-1 expression levels in MCF-7/EPB/TXT cells, which may contribute to abating the drug resistance in the breast cancer cells. Our research in the current study demonstrated that up-regulation of UbcH10 was involved in breast cancer and its knockdown can inhibit the growth of cancer cells and increase the chemosensitivity of the dual drug resistant breast cancer cells to epirubicin and docetaxel, suggesting that UbcH10 may be a promising target for the therapy of breast cancer.

  6. Systematically characterizing and prioritizing chemosensitivity related gene based on Gene Ontology and protein interaction network

    Directory of Open Access Journals (Sweden)

    Chen Xin

    2012-10-01

    Full Text Available Abstract Background The identification of genes that predict in vitro cellular chemosensitivity of cancer cells is of great importance. Chemosensitivity related genes (CRGs have been widely utilized to guide clinical and cancer chemotherapy decisions. In addition, CRGs potentially share functional characteristics and network features in protein interaction networks (PPIN. Methods In this study, we proposed a method to identify CRGs based on Gene Ontology (GO and PPIN. Firstly, we documented 150 pairs of drug-CCRG (curated chemosensitivity related gene from 492 published papers. Secondly, we characterized CCRGs from the perspective of GO and PPIN. Thirdly, we prioritized CRGs based on CCRGs’ GO and network characteristics. Lastly, we evaluated the performance of the proposed method. Results We found that CCRG enriched GO terms were most often related to chemosensitivity and exhibited higher similarity scores compared to randomly selected genes. Moreover, CCRGs played key roles in maintaining the connectivity and controlling the information flow of PPINs. We then prioritized CRGs using CCRG enriched GO terms and CCRG network characteristics in order to obtain a database of predicted drug-CRGs that included 53 CRGs, 32 of which have been reported to affect susceptibility to drugs. Our proposed method identifies a greater number of drug-CCRGs, and drug-CCRGs are much more significantly enriched in predicted drug-CRGs, compared to a method based on the correlation of gene expression and drug activity. The mean area under ROC curve (AUC for our method is 65.2%, whereas that for the traditional method is 55.2%. Conclusions Our method not only identifies CRGs with expression patterns strongly correlated with drug activity, but also identifies CRGs in which expression is weakly correlated with drug activity. This study provides the framework for the identification of signatures that predict in vitro cellular chemosensitivity and offers a valuable

  7. MicroRNA-497 regulates cisplatin chemosensitivity of cervical cancer by targeting transketolase

    Science.gov (United States)

    Yang, Hui; Wu, Xiao-Li; Wu, Kai-Hua; Zhang, Rong; Ju, Li-Li; Ji, Ying; Zhang, Yan-Wei; Xue, Song-Lin; Zhang, Ye-Xin; Yang, Yong-Feng; Yu, Min-Min

    2016-01-01

    Cervical cancer is one of the most lethal malignancies amongst women, partially because it is unresponsive to many chemotherapeutic drugs. The mechanism underlying cisplatin (DDP) resistance in cervical cancer remains largely elusive. In this study, by detecting the 12 most reported down-regulated miRNAs in chemotherapy-sensitive and -resistant cervical cancer cells, we found that miR-497 was significantly reduced in chemotherapy-resistant HeLa/DDP cells and contributed to DDP chemosensitivity. Transketolase (TKT), a thiamine-dependent enzyme that plays a role in the channeling of excess glucose phosphates to glycolysis in the pentose phosphate pathway, was identified as a direct target of miR-497. TKT expression in clinical specimens was characterized by immunohistochemistry and the result showed that TKT was highly expressed in 81.1% (60/74) of samples examined. Data from Oncomine databases revealed that TKT was significantly up-regulated in cervical cancer tissues compared to normal controls. Gain-of-function and loss-of-function studies showed that the miR-497/TKT axis was a critical modulator in DDP chemosensitivity as demonstrated by cell viability and apoptosis assays. Mechanistically, DDP chemosensitivity induced by the miR-497/TKT axis was associated with glutathione (GSH) depletion and reactive oxygen species (ROS) generation, and GSH treatment effectively abrogated miR-497/TKT-mediated chemosensitivity. In conclusion, these findings suggest that a deregulated miR-497/TKT axis has important implications in the cervical cancer cellular response to DDP, and thus targeting this axis may be a promising way to improve chemosensitivity in cervical cancer. PMID:27904781

  8. Effect of GEN1 interference on the chemosensitivity of the breast cancer MCF-7 and SKBR3 cell lines

    OpenAIRE

    Wu, Yunlu; Qian,Ying; ZHOU, GUOZHONG; Lv, Juan; Yan, Qiuyue; Dong, Xuejun

    2016-01-01

    Chemotherapy is a notable method for the treatment of breast cancer. Numerous genes associated with the sensitivity of cancer to chemotherapy have been found. In recent years, evidence has suggested that a particular structure termed Holliday junction (HJ) plays a crucial role in cancer chemosensitivity. Targeting HJ resolvases, such as structure-specific endonuclease subunit SLX4 (Slx4) and MUS81 structure-specific endonuclease subunit (Mus81), significantly increases the chemosensitivity of...

  9. Filamin A (FLNA) modulates chemosensitivity to docetaxel in triple-negative breast cancer through the MAPK/ERK pathway.

    Science.gov (United States)

    Zhao, Pengxin; Ma, Weiyuan; Hu, Zhigang; Zang, Leilei; Tian, Zhisheng; Zhang, Kaili

    2016-04-01

    A previous RNA interference (RNAi) screen identified filamin A (FLNA) as a potential biomarker to predict chemosensitivity in triple-negative breast cancer (TNBC). However, its ability to modulate chemosensitivity and the underlying mechanism has not been investigated. Genetic manipulation of FLNA expression has been performed in an immortalized noncancerous human mammary epithelial cell line and four TNBC cell lines to investigate its effect on chemosensitivity. Western blot analysis was performed to identify the potential signaling pathway involved. Xenograft mouse model was used to examine the in vivo role of FLNA in modulating chemosensitivity. Overexpression of FLNA conferred chemoresistance to docetaxel in noncancerous human mammary epithelial cells. Knockdown of FLNA sensitized four TNBC cell lines, MDA-MB-231, HCC38, Htb126, and HCC1937 to docetaxel which was reversed by reconstituted FLNA expression. Decreased FLNA expression correlated with decreased activation of ERK. Constitutive activation of ERK2 reversed siFLNA-induced chemosensitization. Inhibition of MEK1 recapitulates the effect of FLNA knockdown. MDA-MB-231 xenograft with FLNA knockdown showed enhanced response to docetaxel compared with control xenograft with increased apoptosis. FLNA can function as a modulator of chemosensitivity to docetaxel in TNBC cells through regulation of the MAPK/ERK pathway both in vitro and in vivo. FLNA may serve as a novel therapeutic target for improvement of chemotherapy efficacy in TNBC.

  10. ABC transporters as multidrug resistance mechanisms and the development of chemosensitizers for their reversal

    Directory of Open Access Journals (Sweden)

    Choi Cheol-Hee

    2005-10-01

    Full Text Available Abstract One of the major problems related with anticancer chemotherapy is resistance against anticancer drugs. The ATP-binding cassette (ABC transporters are a family of transporter proteins that are responsible for drug resistance and a low bioavailability of drugs by pumping a variety of drugs out cells at the expense of ATP hydrolysis. One strategy for reversal of the resistance of tumor cells expressing ABC transporters is combined use of anticancer drugs with chemosensitizers. In this review, the physiological functions and structures of ABC transporters, and the development of chemosensitizers are described focusing on well-known proteins including P-glycoprotein, multidrug resistance associated protein, and breast cancer resistance protein.

  11. Peritoneal carcinomatosis from ovarian cancer: chemosensitivity test and tissue markers as predictors of response to chemotherapy

    Directory of Open Access Journals (Sweden)

    Turci Livia

    2011-06-01

    Full Text Available Abstract Background Platinum-based regimens are the treatments of choice in ovarian cancer, which remains the leading cause of death from gynecological malignancies in the Western world. The aim of the present study was to compare the advantages and limits of a conventional chemosensitivity test with those of new biomolecular markers in predicting response to platinum regimens in a series of patients with peritoneal carcinomatosis from ovarian cancer. Methods Fresh surgical biopsy specimens were obtained from 30 patients with primary or recurrent peritoneal carcinomatosis from ovarian cancer. ERCC1, GSTP1, MGMT, XPD, and BRCA1 gene expression levels were determined by Real-Time RT-PCR. An in vitro chemosensitivity test was used to define a sensitivity or resistance profile to the drugs used to treat each patient. Results MGMT and XPD expression was directly and significantly related to resistance to platinum-containing treatment (p = 0.036 and p = 0.043, respectively. Significant predictivity in terms of sensitivity and resistance was observed for MGMT expression (75.0% and 72.5%, respectively; p = 0.03, while high predictivity of resistance (90.9% but very low predictivity of sensitivity (37.5% (p = 0.06 were observed for XPD. The best overall and significant predictivity was observed for chemosensitivity test results (85.7% sensitivity and 91.3% resistance; p = 0.0003. Conclusions The in vitro assay showed a consistency with results observed in vivo in 27 out of the 30 patients analyzed. Sensitivity and resistance profiles of different drugs used in vivo would therefore seem to be better defined by the in vitro chemosensitivity test than by expression levels of markers.

  12. Intrinsic chemosensitivity of individual nucleus tractus solitarius (NTS) and locus coeruleus (LC) neurons from neonatal rats.

    Science.gov (United States)

    Nichols, Nicole L; Hartzler, Lynn K; Conrad, Susan C; Dean, Jay B; Putnam, Robert W

    2008-01-01

    Chemosensitive (CS) neurons are found in discrete brainstem regions, but whether the CS response of these neurons is due to intrinsic chemosensitivity of individual neurons or is mediated by changes in chemical and/or electrical synaptic input is largely unknown. We studied the effect of synaptic blockade (11.4 mM Mg2+/0.2mM Ca2+) solution (SNB) and a gap junction uncoupling agent carbenoxolone (CAR--100 microM) on the response of neurons from two CS brainstem regions, the NTS and the LC. In NTS neurons, SNB decreased spontaneous firing rate (FR). We calculated the magnitude of the FR response to hypercapnic acidosis (HA; 15% CO2) using the Chemosensitivity Index (CI). The percentage of NTS neurons activated and CI were the same in the absence and presence of SNB. Blocking gap junctions with CAR did not significantly alter spontaneous FR. CAR did not alter the CI in NTS neurons and resulted in a small decrease in the percentage of activated neurons, which was most evident in NTS neurons from rats younger than postnatal day 10. In LC neurons, SNB resulted in an increase in spontaneous FR. As with NTS neurons, SNB did not alter the percentage of activated neurons or the CI in LC neurons. CAR resulted in a small increase in spontaneous FR in LC neurons. In contrast, CAR had a marked effect on the response of LC neurons to HA: a reduced percentage of CS LC neurons and decreased CI. In summary, both NTS and LC neurons appear to contain intrinsically CS neurons. CS neurons from the two regions receive different tonic input in slices (excitatory for NTS and inhibitory for LC); however, blocking chemical synaptic input does not affect the CS response in either region. In NTS neurons, gap junction coupling plays a small role in the CS response, but gap junctions play a major role in the chemosensitivity of many LC neurons.

  13. Knockdown of cullin 4A inhibits growth and increases chemosensitivity in lung cancer cells.

    Science.gov (United States)

    Hung, Ming-Szu; Chen, I-Chuan; You, Liang; Jablons, David M; Li, Ya-Chin; Mao, Jian-Hua; Xu, Zhidong; Lung, Jr-Hau; Yang, Cheng-Ta; Liu, Shih-Tung

    2016-07-01

    Cullin 4A (Cul4A) has been observed to be overexpressed in various cancers. In this study, the role of Cul4A in the growth and chemosensitivity in lung cancer cells were studied. We showed that Cul4A is overexpressed in lung cancer cells and tissues. Knockdown of the Cul4A expression by shRNA in lung cancer cells resulted in decreased cellular proliferation and growth in lung cancer cells. Increased sensitivity to gemcitabine, a chemotherapy drug, was also noted in those Cul4A knockdown lung cancer cells. Moreover, increased expression of p21, transforming growth factor (TGF)-β inducible early gene-1 (TIEG1) and TGF beta-induced (TGFBI) was observed in lung cancer cells after Cul4A knockdown, which may be partially related to increased chemosensitivity to gemcitabine. G0/G1 cell cycle arrest was also noted after Cul4A knockdown. Notably, decreased tumour growth and increased chemosensitivity to gemcitabine were also noted after Cul4A knockdown in lung cancer xenograft nude mice models. In summary, our study showed that targeting Cul4A with RNAi or other techniques may provide a possible insight to the development of lung cancer therapy in the future.

  14. Enhancement of Chemosensitivity by Stathmin-1 Silencing in Gastric Cancer Cells In Situ and In Vivo.

    Science.gov (United States)

    Meng, Zhi-jian; Tao, Ke

    2016-01-01

    Reports show that the stathmin gene may have a close relationship with tumor chemotherapeutic sensitivity. However, the effect of stathmin-1 on the chemosensitivity of gastric cancer to docetaxel has not been clearly determined. siRNA targeting stathmin-1 was introduced. The cell growth inhibition, expression of associated proteins, cell cycle, and apoptosis were evaluated by MTT, Western blot, and flow cytometric assays, respectively. The influence of silencing stathmin-1 was detected in situ and in vivo. SGC7901/docetaxel cells are the drug-resistant cells. After silencing stathmin-1, the resistance index (RI) reduced to 3.41, the expressions of STMN-1, MDR1, and ERCC1 were downregulated, but caspase 3 was upregulated. Stathmin-1 siRNA could improve the chemosensitivity of gastric cancer cells to docetaxel, making the percentage of cells at the sub-G1 stage increase and promote apoptosis. The growth of transplantation tumor was significantly suppressed. Therefore, stathmin-1 might be a potential target for enhancing the chemosensitivity of gastric cancer.

  15. Increased leucine-rich repeats and immunoglobulin- like domains 1 expression enhances chemosensitivity in glioma

    Institute of Scientific and Technical Information of China (English)

    Baohui Liu; Shenqi Zhang; Dong Ruan; Xiaonan Zhu; Zhentao Guo; Huimin Dong; Mingmin Yan; Qianxue Chen; Daofeng Tian; Liquan Wu; Junmin Wang; Qiang Cai; Heng Shen; Baowei Ji; Long Wang

    2011-01-01

    Leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) is an anti-oncogene.LRIG1 is correlated with Bcl-2 in ependymomas.Decreased Bcl-2 and manganese superoxide dismutase expression can improve the chemosensitivity of glioma.In the present study, a tissue microarray of human brain astrocytomas was constructed.To investigate the relationship of LRIG1 with Bcl-2 and manganese superoxide dismutase, LRIG1, Bcl-2 and manganese superoxide dismutase expression in our tissue microarray was determined using immunohistochemistry.In addition, we constructed the LRIG1-U251 cell line, and its responses to doxorubicin and temozolomide were detected using the MTT assay.Results showed that LRIG1 expression was significantly negatively correlated with Bcl-2 and manganese superoxide dismutase expression in glioma.Also, proliferation of LRIG1-U251 cells exposed to doxorubicin or temozolomide was significantly inhibited, i.e.in the LRIG1-U251 cell line, the chemosensitivity to doxorubicin and temozolomide was increased.This indicates that increased LRIG1 expression produces a chemosensitivity in glioma.

  16. Development of chemosensitivity in neurons from the nucleus tractus solitarii (NTS) of neonatal rats.

    Science.gov (United States)

    Conrad, Susan C; Nichols, Nicole L; Ritucci, Nick A; Dean, Jay B; Putnam, Robert W

    2009-03-31

    We studied the development of chemosensitivity during the neonatal period in rat nucleus tractus solitarii (NTS) neurons. We determined the percentage of neurons activated by hypercapnia (15% CO(2)) and assessed the magnitude of the response by calculating the chemosensitivity index (CI). There were no differences in the percentage of neurons that were inhibited (9%) or activated (44.8%) by hypercapnia or in the magnitude of the activated response (CI 164+/-4.9%) in NTS neurons from neonatal rats of all ages. To assess the degree of intrinsic chemosensitivity in these neurons we used chemical synaptic block medium and the gap junction blocker carbenoxolone. Chemical synaptic block medium slightly decreased basal firing rate but did not affect the percentage of NTS neurons that responded to hypercapnia at any neonatal age. However, in neonates aged NTS neurons activated by hypercapnia in neonatal rats of any age. In summary, the response of NTS neurons from neonatal rats appears to be intrinsic and largely unchanged throughout early development. In young neonates (NTS neurons that respond to hypercapnia or the magnitude of that response.

  17. Organ-Tumor-on-a-Chip for Chemosensitivity Assay: A Critical Review

    Directory of Open Access Journals (Sweden)

    Navid Kashaninejad

    2016-07-01

    Full Text Available With a mortality rate over 580,000 per year, cancer is still one of the leading causes of death worldwide. However, the emerging field of microfluidics can potentially shed light on this puzzling disease. Unique characteristics of microfluidic chips (also known as micro-total analysis system make them excellent candidates for biological applications. The ex vivo approach of tumor-on-a-chip is becoming an indispensable part of personalized medicine and can replace in vivo animal testing as well as conventional in vitro methods. In tumor-on-a-chip, the complex three-dimensional (3D nature of malignant tumor is co-cultured on a microfluidic chip and high throughput screening tools to evaluate the efficacy of anticancer drugs are integrated on the same chip. In this article, we critically review the cutting edge advances in this field and mainly categorize each tumor-on-a-chip work based on its primary organ. Specifically, design, fabrication and characterization of tumor microenvironment; cell culture technique; transferring mechanism of cultured cells into the microchip; concentration gradient generators for drug delivery; in vitro screening assays of drug efficacy; and pros and cons of each microfluidic platform used in the recent literature will be discussed separately for the tumor of following organs: (1 Lung; (2 Bone marrow; (3 Brain; (4 Breast; (5 Urinary system (kidney, bladder and prostate; (6 Intestine; and (7 Liver. By comparing these microchips, we intend to demonstrate the unique design considerations of each tumor-on-a-chip based on primary organ, e.g., how microfluidic platform of lung-tumor-on-a-chip may differ from liver-tumor-on-a-chip. In addition, the importance of heart–liver–intestine co-culture with microvasculature in tumor-on-a-chip devices for in vitro chemosensitivity assay will be discussed. Such system would be able to completely evaluate the absorption, distribution, metabolism, excretion and toxicity (ADMET of

  18. Electrophysiologic testing guided risk stratification approach for sudden cardiac death beyond the left ventricular ejection fraction

    Institute of Scientific and Technical Information of China (English)

    Konstantinos A Gatzoulis; Dimitris Tsiachris; Petros Arsenos; Dimitris Tousoulis

    2016-01-01

    Sudden cardiac death threats ischaemic and dilated cardiomyopathy patients. Anti- arrhythmic protection may be provided to these patients with implanted cardiac defibrillators(ICD), after an efficient risk stratification approach. The proposed risk stratifier of an impaired left ventricular ejection fraction has limited sensitivity meaning that a significant number of victims will remain undetectable by this risk stratification approach because they have a preserved left ventricular systolic function. Current risk stratification strategies focus on combinations of non invasive methods like T wave alternans, late potentials, heart rate turbulence, deceleration capacity and others, with invasive methods like the electrophysiologic study. In the presence of an electrically impaired substrate with formed post myocardial infarction fibrotic zones, programmed ventricular stimulation provides important prognostic information for the selection of the patients expected to benefit from an ICD implantation, while due to its high negative predictive value, patients at low risk level may also be detected. Clustering evidence from different research groups and electrophysiologic labs support an electrophysiologic testing guided risk stratification approach for sudden cardiac death.

  19. Electrophysiologic testing guided risk stratification approach for sudden cardiac death beyond the left ventricular ejection fraction.

    Science.gov (United States)

    Gatzoulis, Konstantinos A; Tsiachris, Dimitris; Arsenos, Petros; Tousoulis, Dimitris

    2016-01-26

    Sudden cardiac death threats ischaemic and dilated cardiomyopathy patients. Anti- arrhythmic protection may be provided to these patients with implanted cardiac defibrillators (ICD), after an efficient risk stratification approach. The proposed risk stratifier of an impaired left ventricular ejection fraction has limited sensitivity meaning that a significant number of victims will remain undetectable by this risk stratification approach because they have a preserved left ventricular systolic function. Current risk stratification strategies focus on combinations of non invasive methods like T wave alternans, late potentials, heart rate turbulence, deceleration capacity and others, with invasive methods like the electrophysiologic study. In the presence of an electrically impaired substrate with formed post myocardial infarction fibrotic zones, programmed ventricular stimulation provides important prognostic information for the selection of the patients expected to benefit from an ICD implantation, while due to its high negative predictive value, patients at low risk level may also be detected. Clustering evidence from different research groups and electrophysiologic labs support an electrophysiologic testing guided risk stratification approach for sudden cardiac death.

  20. EFFECTS OF p16INK4 GENE ON CHEMOSENSITIVITY OF HUMAN GLIOMA U251 CELL LINE TO TENIPOSIDE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To determine the effects on the cell growth, tumorigenicity and chemosensitivity of p16/CDK4I in human glioma. Methods: p16 gene was transfected into U251 cells by lipofectin. Expression of exogenous p16 gene was confirmed by immunohistochemistry and Northern blot. The effects of exogenous p16 gene on the growth and chemosensitivity to teniposide were examined. Results: Expression of exogenous p16 gene inhibited the growth dramatically in vitro. G1 arrest of tumor cells was observed. However, wt p16-positive U251 was less sensitive than control cell lines and the number of apoptotic cells after chemotherapy was reduced. Conclusion: The expression of exogenous p16 gene could inhibit the growth of glioma. On the other hand, the chemosensitivity to teniposide of p16-positive U251 was decreased.

  1. Noscapine chemosensitization enhances docetaxel anticancer activity and nanocarrier uptake in triple negative breast cancer

    Science.gov (United States)

    Doddapaneni, Ravi; Patel, Ketan; Chowdhury, Nusrat; Singh, Mandip

    2016-01-01

    Chemosensitization and enhanced delivery to solid tumor are widely explored strategies to augment the anticancer efficacy of existing chemotherapeutics agents. The aim of current research was to investigate the role of low dose Noscapine (Nos) in potentiating docetaxel cytotoxicity and enhancing tumor penetration of nanocarriers. The objectives are; (1) To evaluate the chemo-sensitizing effect of Nos in combination with docetaxel (DTX), and to elucidate the possible mechanism (2) To investigate the effect of low dose Nos on tumor stroma and enhancing nanocarrier uptake in triple negative breast cancer (TNBC) bearing nude mice. Cytotoxicity and flow cytometry analysis of DTX in Nos (4 µM) pre-treated MDA-MB-231 cells showed 3.0-fold increase in cell killing and 30% increase in number of late apoptotic cells, respectively. Stress transducer p38 phosphorylation was significantly upregulated with Nos exposure. DTX showed remarkable downregulation in expression of bcl-2, survivin and pAKT in Nos pre-treated MDA-MB-231 cells. Nos pre-sensitization significantly (p < 0.02) enhanced the anti-migration effect of DTX. In vivo studies in orthotopic TNBC tumor bearing mice showed marked reduction in tumor collagen-I levels and significantly (p < 0.03) higher intra-tumoral uptake of coumarin-6 loaded PEGylated liposomes (7-fold) in Nos treated group. Chemo-sensitization and anti-fibrotic effect of Nos could be a promising approach to increase anticancer efficacy of DTX which can be used for other nanomedicinal products. PMID:27177833

  2. Role and mechanism of Twist1 in modulating the chemosensitivity of FaDu cells.

    Science.gov (United States)

    Lu, Sumei; Yu, Liang; Mu, Yakui; Ma, Juke; Tian, Jiajun; Xu, Wei; Wang, Haibo

    2014-07-01

    Multidrug resistance (MDR) is one of the most important obstacles affecting the efficacy of chemotherapy treatments for numerous types of cancer. In the present study, we have demonstrated the possible function of Twist1 in the chemosensitivity of head and neck squamous cell carcinoma (HNSCC) and have identified that its mechanism maybe associated with MDR1/P-gp regulation. To investigate this, the hypopharyngeal cancer cell line, FaDu, and its MDR cell line induced by taxol, FaDu/T, were employed. Stable transfectants targeted to Twist1 overexpression and Twist1 silencing based on FaDu were also conducted. Morphological observation, flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR), western blotting and laser scanning confocal microscope detection were utilized to detect the associations between Twist1 and the chemosensitivity of FaDu cells. Our results demonstrated that Twist1 and MDR1/P-gp were upregulated in FaDu/T cells in a MDR dose-dependent manner. The anti-apoptotic capabilities of FaDu/T cells were enhanced during MDR progression, with apoptosis-related proteins (Bcl-2, Bax, activated caspase-3 and caspase-9) changing to resist apoptosis. Twist1 overexpression decreased the sensitivity of cells to taxol as revealed by a significant increase in MDR1/P-gp and IC50 (Pcell death, and inhibited Ca2+ release induced by taxol (Pcells also confirmed this result. This study provided evidence that alterations of Twist1 expression modulates the chemosensitivity of FaDu cells to taxol. Therefore, Twist1 knockdown may be a promising treatment regimen for advanced hypopharyngeal carcinoma patients with MDR.

  3. Prediction of drug efficacy for cancer treatment based on comparative analysis of chemosensitivity and gene expression data

    DEFF Research Database (Denmark)

    Wan, Peng; Li, Qiyuan; Larsen, Jens Erik Pontoppidan;

    2012-01-01

    compounds with reliable experimental half maximum growth inhibitions (GI50) values for 30 cell lines from the NCI60 data set and evaluated their growth inhibitory effect (chemosensitivity) with respect to tissue of origin. This was done by identifying natural clusters in the chemosensitivity data set...... and in a data set of expression profiles of 1901 genes for the corresponding tumor cell lines. Five clusters were identified based on the gene expression data using self-organizing maps (SOM), comprising leukemia, melanoma, ovarian and prostate, basal breast, and luminal breast cancer cells, respectively...

  4. Empirical studies about quercetin increasing chemosensitivity on human lung adenocarcinoma cell line A549

    Institute of Scientific and Technical Information of China (English)

    Xuejun Zhan; Runxiang Zhang; Yanping Xu; Shuhua Yang; Daze Xie; Liwei Tan

    2012-01-01

    Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods: Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line (A549/S) was induced to VCR-resistant human lung adenocarcinoma cell line (A549/VCR). MTT assay was adapted for examing the 50% inhibition (IC50) value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results: IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 mg/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 1.21, respectively. When quercetin at concentration of 50, 100 and 200 μmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased (P < 0.05 – P < 0.01). Conclusion: The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549/VCR.

  5. Paclitaxel stimulates chromosomal fusion and instability in cells with dysfunctional telomeres: Implication in multinucleation and chemosensitization

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Woo, Seon Rang [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kang, Chang-Mo [Laboratory of Cytogenetics and Tissue Regeneration, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Juhn, Kyoung-Mi; Ju, Yeun-Jin; Shin, Hyun-Jin; Joo, Hyun-Yoo; Park, Eun Ran; Park, In-chul; Hong, Sung Hee; Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Jung-Kee [Department of Life Science and Genetic Engineering, Paichai University, Daejeon 302-735 (Korea, Republic of); Kim, Hae Kwon [Department of Biotechnology, Seoul Woman' s University, Seoul 139-774 (Korea, Republic of); Cho, Myung-Haing [Laboratory of Toxicology, College of Veterinary Medicine, Seoul National University, Seoul 151-74-2 (Korea, Republic of); Park, Gil Hong [Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Lee, Kee-Ho, E-mail: khlee@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

    2011-01-14

    Research highlights: {yields} Paclitaxel serves as a stimulator of chromosomal fusion in cells in which telomeres are dysfunctional. {yields} Typical fusions involve p-arms, but paclitaxel-induced fusions occur between both q- and p-arms. {yields} Paclitaxel-stimulated fusions in cells in which telomeres are dysfunctional evoke prolonged G2/M cell cycle arrest and delay multinucleation. {yields} Upon telomere erosion, paclitaxel promotes chromosomal instability and subsequent apoptosis. {yields} Chromosomal fusion enhances paclitaxel chemosensitivity under telomere dysfunction. -- Abstract: The anticancer effect of paclitaxel is attributable principally to irreversible promotion of microtubule stabilization and is hampered upon development of chemoresistance by tumor cells. Telomere shortening, and eventual telomere erosion, evoke chromosomal instability, resulting in particular cellular responses. Using telomerase-deficient cells derived from mTREC-/-p53-/- mice, here we show that, upon telomere erosion, paclitaxel propagates chromosomal instability by stimulating chromosomal end-to-end fusions and delaying the development of multinucleation. The end-to-end fusions involve both the p- and q-arms in cells in which telomeres are dysfunctional. Paclitaxel-induced chromosomal fusions were accompanied by prolonged G2/M cell cycle arrest, delayed multinucleation, and apoptosis. Telomere dysfunctional cells with mutlinucleation eventually underwent apoptosis. Thus, as telomere erosion proceeds, paclitaxel stimulates chromosomal fusion and instability, and both apoptosis and chemosensitization eventually develop.

  6. Relationship between single nucleotide polymorphisms in the deoxycytidine kinase gene and chemosensitivity of gemcitabine in six pancreatic cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    SI Shuang; LIAO Quan; ZHAO Yu-pei; HU Ya; ZHANG Qiang; YOU Li-li

    2011-01-01

    Background Single nucleotide polymorphisms (SNPs) in the deoxycytidine kinase (dCK) gene are associated with chemosensitivity to nucleoside analogs. 2',2'-Difluoro 2'-deoxycytidine (gemcitabine) is a first-line nucleoside analog drug in the treatment of pancreatic cancer. However, the association between SNPs in the dCK gene and chemosensitivity to gemcitabine has not been fully established. Therefore, the present study aimed to investigate the relationship between SNPs in the dCKgene and chemosensitivity to gemcitabine in human pancreatic cancer cell lines.Methods Seven SNPs in the dCK gene were sequenced in six human pancreatic cancer cell lines. The chemosensitivity of these six cell lines to gemcitabine were evaluated in vitro with a Cell Counting Kit-8 (CCK-8) test.Inhibition rates were used to express the chemosensitivity of pancreatic cancer cell lines to gemcitabine.Results The genotype of the A9846G SNP in the dCKgene was determined in six human pancreatic cancer cell lines.The cell lines BxPC-3 and T3M4 carried the A9846G SNP genotype AG, whereas cell lines AsPC-1, Mia PaCa2, SW1990 and SU86.86 carried the GG genotype. Cell lines with the AG genotype (BxPC-3 and T3M4) were more sensitive to gemcitabine compared with cell lines with the GG genotype (AsPC-1, Mia PaCa2, SW1990 and SU86.86) and significantly different inhibition rates were observed between cell lines carrying the AG and GG genotypes (P <0.01).Conclusions Variants in the A9846G SNP of the dCK gene were associated with sensitivity to gemcitabine in pancreatic cancer cell lines. The dCK A9846G SNP may act as a genetic marker to predict chemotherapy efficacy of gemcitabine in pancreatic cancer.

  7. Chemosensitivity assay in mice prostate tumor: Preliminary report of flow cytometry, DNA fragmentation, ion ratiometric methods of anti-neoplastic drug monitoring

    OpenAIRE

    2004-01-01

    Abstract Flow cytometry, DNA fragmentation, ion ratiomateric analysis and NMR peaks characterized drug chemosensitivity of antineoplastic drugs. Hypotheses were: 1. The chemosensitive effect of different cancer cell lines is characteristic; 2. DNA fragmentation, ion ratiometric analysis suggest apoptosis status of tumor cells. Methods PC-3 cell lines were compared with DU-145, LNCaP cell lines in culture for the [Na]i and [Ca]i ion sensing dyes, cell death, NMR peaks and apoptosis staining fo...

  8. In vitro platinum drug chemosensitivity of human cervical squamous cell carcinoma cell lines with intrinsic and acquired resistance to cisplatin.

    OpenAIRE

    Mellish, K. J.; Kelland, L R; Harrap, K. R.

    1993-01-01

    The platinum drug chemosensitivity of five human cervical squamous cell carcinoma cell lines (HX/151, HX/155, HX/156, HX/160 and HX/171) derived from previously untreated patients has been determined. Compared to our data obtained previously using human ovarian carcinoma cell lines, all five lines were relatively resistant to cisplatin, carboplatin, iproplatin and tetraplatin. One of the lines (HX/156) was exceptionally sensitive to the novel platinum (IV) ammine/amine dicarboxylates JM216 [b...

  9. STUDY ON RELATIONSHIP BETWEEN CHEMOSENSITIVITY OF BREAST CANCER AND EXPRESSION OF p73α AND p53

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xin; SUN Zhi-jun

    2005-01-01

    Objective: To investigate the relationship between the expression of p73α and p53 versus the chemosensitivity in breast cancer cells. Methods: Twelve surgical samples of breast cancer diagnosed by pathology were used. The cancer sample cells were separately cultured in the incubator at 37℃, 5% CO2 in vitro. The relative inhibition rate of cancer cells by 4 kinds of anticancer drugs, which were EPI, MMC, 5-Fu and DDP, were assayed by MTT method. Immunocytochemistry was used to detect the expression of p73α and p53 in the cancer cells. Results: The positive expression of p73α was found in 5/12 (41.67%), and p53 positive expression rate was 50.0% (6/12). The relative inhibition rate of MMC, EPI, 5-Fu and DDP were significantly higher in the p73α positive cancer cells than in the p73α negative cancer cells. A positive correlation was found between expression of p73α and chemosensitivity for all the four anticancer drugs. Conclusion: The expression of p73α is related with the chemosensitivity of the breast cancer cells, and it may become one of the markers for judging the effect of chemotherapy in clinic.

  10. In vivo enhancement of chemosensitivity of human salivary gland cancer cells by overexpression of TGF-beta stimulated clone-22.

    Science.gov (United States)

    Omotehara, F; Uchida, D; Hino, S; Begum, N M; Yoshida, H; Sato, M; Kawamata, H

    2000-01-01

    We have isolated transforming growth factor-beta-stimulated clone-22 (TSC-22) cDNA as an anti-cancer drug-inducible gene in a human salivary gland cancer cell line, TYS. We have previously reported that TSC-22 negatively regulates the growth of TYS cells, and that overexpression of TSC-22 protein in TYS cells enhanced the in vitro chemosensitivity of the cells. In this study, we examined the in vivo chemosensitivity of TSC-22-expressing TYS cells. TSC-22-expressing TYS cells formed tumors in nude mice, but tumors formed by TSC-22-expressing TYS cells were significantly smaller than tumors formed by control cells (pway ANOVA). Furthermore, intraperitoneal injection of 5-fluorouracil (5-FU) markedly inhibited the growth of the TSC-22-expressing TYS tumors, but did not affect the growth of control tumors. It was found by TUNEL assay that TSC-22-expressing TYS tumors were induced to undergo apoptosis by 5-FU treatment. These findings suggest that overexpression of TSC-22 protein in TYS cells enhances the in vivo chemosensitivity of the cells to 5-FU via induction of apoptosis.

  11. Tf-PEG-PLL-PLGA nanoparticles enhanced chemosensitivity for hypoxia-responsive tumor cells

    Directory of Open Access Journals (Sweden)

    Liu P

    2016-08-01

    Full Text Available Ping Liu,1 Haijun Zhang,1 Xue Wu,1 Liting Guo,1 Fei Wang,1 Guohua Xia,2 Baoan Chen,1 HaiXiang Yin,3 Yonglu Wang,3 Xueming Li3 1Department of Hematology and Oncology, Key Department of Jiangsu Province, Zhongda Hospital, 2Department of Hematology and Oncology, Medical School of Southeast University, 3School of Pharmacy, Nanjing University of Technology, Nanjing, People’s Republic of China Abstract: Hypoxia is an inseparable component of the solid tumor as well as the bone marrow microenvironment. In this study, we investigated the effect of the novel polyethylene glycol (PEG-poly L-lysine (PLL-poly lactic-co-glycolic acid (PLGA based nanoparticles (NPs modified by transferrin (Tf loaded with daunorubicin (DNR (DNR-Tf-PEG-PLL-PLGA-NPs, abbreviated as DNR-Tf-NPs on leukemia cells (K562 under hypoxia. In vitro and in vivo tests to determine the effect of the enhanced chemosensitivity were evaluated using the immunofluorescence, flow cytometry, 3,-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2-tetrazoliumbromide assay, Western blot analysis, histopathological examination, and immunohistochemistry analysis. Under hypoxia, K562 cells were hypoxia-responsive with the inhibitory concentration 50% (IC50 of DNR increased, resulting in chemotherapy insensitivity. By targeting the transferrin receptor (TfR on the surface of K562 cells, DNR-Tf-NPs led to an increased intracellular DNR level, enhancing drug sensitivity of K562 cells to DNR with a decreased IC50, even under hypoxia. We further detected the protein levels of hypoxia-inducible factor-1α (HIF-1α, Bcl-2, Bax, and caspase-3 in K562 cells. The results indicated that DNR-Tf-NPs downregulated HIF-1α and induced apoptosis to overcome hypoxia. In the xenograft model, injection of DNR-Tf-NPs significantly suppressed tumor growth, and the immunosignals of Ki67 in DNR-Tf-NPs group was significantly lower than the other groups. It was therefore concluded that DNR-Tf-NPs could be a promising candidate for

  12. Overexpression of miR-100 inhibits cell proliferation, migration, and chemosensitivity in human glioblastoma through FGFR3

    Directory of Open Access Journals (Sweden)

    Luan YX

    2015-11-01

    Full Text Available Yongxin Luan,1 Shuyan Zhang,1 Ling Zuo,2 Lixiang Zhou1 1Department of Neurosurgery, First Bethune Hospital of Jilin University, 2Department of Ophthalmology, Second Bethune Hospital of Jilin University, Changchun, People’s Republic of China Background: Glioblastoma multiforme is one of the most deadly forms of brain cancer. We investigated the regulatory effects of microRNA-100 (miR-100 on cell proliferation, migration, and chemosensitivity in human glioblastoma. Methods: miR-100 expression was assessed by quantitative real-time polymerase chain reaction in both glioblastoma cells and human tumors. Lentiviruses of miR-100 mimics and inhibitors were transfected into U251 and T98G cells. The regulatory effects of either overexpressing or downregulating miR-100 on glioblastoma were evaluated by a viability assay, growth assay, migration assay, chemosensitivity assay, and an in vivo tumor transplantation assay. Expression of fibroblast growth factor receptor 3 (FGFR3, the bioinformatically predicted target of miR-100, was examined by Western blot in glioblastoma. FGFR3 was then ectopically overexpressed in U251 and T98G cells, and its effects on miR-100-mediated cancer regulation were evaluated by growth, migration, and chemosensitivity assays. Results: MiR-100 was markedly downregulated in both glioblastoma cell lines and human tumors. Overexpressing miR-100 through lentiviral transfection in U251 and T98G cells significantly inhibited cancer growth (both in vitro and in vivo and migration and increased chemosensitivity to cisplatin and 1, 3-bis (2-chloroethyl-l-nitrosourea, whereas downregulation of miR-100 had no effects on development of cancer. FGFR3 was directly regulated by miR-100 in glioblastoma. Ectopically overexpressing FGFR3 was able to ameliorate the anticancer effects of upregulation of miR-100 on glioblastoma growth, migration, and chemosensitivity. Conclusion: MiR-100 was generally downregulated in glioblastoma. Overexpressing mi

  13. Chemosensitivity of MCF-7 cells to eugenol: release of cytochrome-c and lactate dehydrogenase

    Science.gov (United States)

    Al Wafai, Rana; El-Rabih, Warde; Katerji, Meghri; Safi, Remi; El Sabban, Marwan; El-Rifai, Omar; Usta, Julnar

    2017-01-01

    Phytochemicals have been extensively researched for their potential anticancer effects. In previous study, direct exposure of rat liver mitochondria to eugenol main ingredient of clove, uncoupled mitochondria and increased F0F1ATPase activity. In the present study, we further investigated the effects of eugenol on MCF-7 cells in culture. Eugenol demonstrated: a dose-dependent decrease in viability (MTT assay), and proliferation (real time cell analysis) of MCF-7 cells, (EC50: 0.9 mM); an increase in reactive oxygen species; a decrease in ATP level and mitochondrial membrane potential (MitoPT JC-1 assay); and a release of cytochrome-c and lactate dehydrogenase (Cytotoxicity Detection Kit PLUS) into culture media at eugenol concentration >EC50. Pretreatment with the antioxidants Trolox and N-acetyl cysteine partially restored cell viability and decreased ROS, with Trolox being more potent. Expression levels of both anti- and pro-apoptotic markers (Bcl-2 and Bax, respectively) decreased with increasing eugenol concentration, with no variation in their relative ratios. Eugenol-treated MCF-7 cells overexpressing Bcl-2 exhibited results similar to those of MCF-7. Our findings indicate that eugenol toxicity is non-apoptotic Bcl-2 independent, affecting mitochondrial function and plasma membrane integrity with no effect on migration or invasion. We report here the chemo-sensitivity of MCF-7 cells to eugenol, a phytochemical with anticancer potential. PMID:28272477

  14. Interleukin-8 associates with adhesion, migration, invasion and chemosensitivity of human gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Wen-Xia Kuai; Qiong wang; Xiao-Zhong Yang; Yao Zhao; Ren Yu; Xiao-Jun Tang

    2012-01-01

    AIM:To investigate the relationship between Interleukin-8 (IL-8) and proliferation,adhesion,migration,invasion and chemosensitivity of gastric cancer (GC) cells.METHODS:The IL-8 cDNA was stably transfected into human GC cell line MKN-45 and selected IL-8-secreting transfectants.The expression of IL-8 in human GC cell line KATO-Ⅲ was inhibited by RNA interference.The expressions of mRNA and protein of IL-8 in GC cells were detected by real-time reverse transcriptionpolymerase chain reaction or enzyme-linked immunosorbent assay (ELISA).RESULTS:The overexpression of IL-8 resulted in an increased cell adhesion,migration and invasion,and a significant resistance to oxaliplatin in MKN-45 cells.Inhibition of IL-8 expression with small interfering RNA decreased the adhesion,migration and invasion functions and oxaliplatin resistance in KATO-Ⅲ cells.IL-8 increased NF-кB and Akt activities and adhesion molecules ICAM-1,VCAM-1,and CD44 expression in GC cells.CONCLUSION:Overexpression of IL-8 promotes the adhesion,migration,invasion,and chemoresistance of GC cells,indicating that IL-8 is an important therapeutic target in GC.

  15. Live tissue viability and chemosensitivity assays using digital holographic motility contrast imaging.

    Science.gov (United States)

    An, Ran; Turek, John; Matei, Daniela Elena; Nolte, David

    2013-01-01

    Holographic optical coherence imaging is an en face form of optical coherence tomography that uses low-coherence digital holography as a coherence gate to select light from a chosen depth inside scattering tissue. By acquiring successive holograms at a high camera frame rate at a fixed depth, dynamic speckle provides information concerning dynamic light scattering from intracellular motility. Motility contrast imaging (MCI) uses living motion as a label-free and functional biomarker. MCI provides a new form of viability assay and also is applicable for proliferation and cytotoxicity assays. The results presented here demonstrate that low-coherence digital holography can extract viability information from biologically relevant three-dimensional (3D) tissue based on multicellular tumor spheroids by moving beyond the format of two-dimensional cell culture used for conventional high-content analysis. This paper also demonstrates the use of MCI for chemosensitivity assays on tumor exgrafts of excised ovarian cancer tumors responding to standard-of-care cisplatin chemotherapy. This ex vivo application extends the applicability of MCI beyond 3D tissue culture grown in vitro.

  16. Integration of photothermal therapy and synergistic chemotherapy by a porphyrin self-assembled micelle confers chemosensitivity in triple-negative breast cancer.

    Science.gov (United States)

    Su, Shishuai; Ding, Yanping; Li, Yiye; Wu, Yan; Nie, Guangjun

    2016-02-01

    Triple-negative breast cancer is a malignant cancer type with a high risk of early recurrence and distant metastasis. Unlike other breast cancers, triple-negative breast cancer is lack of targetable receptors and, therefore, patients largely receive systemic chemotherapy. However, inevitable adverse effects and acquired drug resistance severely constrain the therapeutic outcome. Here we tailor-designed a porphyrin-based micelle that was self-assembled from a hybrid amphiphilic polymer comprising polyethylene glycol, poly (d, l-lactide-co-glycolide) and porphyrin. The bilayer micelles can be simultaneously loaded with two chemotherapeutic drugs with synergistic cytotoxicity and distinct physiochemical properties, forming a uniform and spherical nanostructure. The drug-loaded micelles showed a tendency to accumulate in the tumor and can be internalized by tumor cells for drug release in acidic organelles. Under near-infrared laser irradiation, high density of self-quenched porphyrins in the hydrophobic layer absorbed light efficiently and converted into an excited state, leading to the release of sufficient heat for photothermal therapy. The integration of localized photothermal effect and synergistic chemotherapy conferred great chemosensitivity to cancer cells and achieved tumor regression using about 1/10 of traditional drug dosage. As a result, chemotherapy-associated adverse effects were successfully avoided. Our present study established a novel porphyrin-based nanoplatform with photothermal activity and expanded drug loading capacity, providing new opportunities for challenging conventional chemotherapy and fighting against stubborn triple-negative breast cancer.

  17. Cell-cycle fate-monitoring distinguishes individual chemosensitive and chemoresistant cancer cells in drug-treated heterogeneous populations demonstrated by real-time FUCCI imaging.

    Science.gov (United States)

    Miwa, Shinji; Yano, Shuya; Kimura, Hiroaki; Yamamoto, Mako; Toneri, Makoto; Matsumoto, Yasunori; Uehara, Fuminari; Hiroshima, Yukihiko; Murakami, Takashi; Hayashi, Katsuhiro; Yamamoto, Norio; Bouvet, Michael; Fujiwara, Toshiyoshi; Tsuchiya, Hiroyuki; Hoffman, Robert M

    2015-01-01

    Essentially every population of cancer cells within a tumor is heterogeneous, especially with regard to chemosensitivity and resistance. In the present study, we utilized the fluorescence ubiquitination-based cell cycle indicator (FUCCI) imaging system to investigate the correlation between cell-cycle behavior and apoptosis after treatment of cancer cells with chemotherapeutic drugs. HeLa cells expressing FUCCI were treated with doxorubicin (DOX) (5 μM) or cisplatinum (CDDP) (5 μM) for 3 h. Cell-cycle progression and apoptosis were monitored by time-lapse FUCCI imaging for 72 h. Time-lapse FUCCI imaging demonstrated that both DOX and CDDP could induce cell cycle arrest in S/G2/M in almost all the cells, but a subpopulation of the cells could escape the block and undergo mitosis. The subpopulation which went through mitosis subsequently underwent apoptosis, while the cells arrested in S/G2/M survived. The present results demonstrate that chemoresistant cells can be readily identified in a heterogeneous population of cancer cells by S/G2/M arrest, which can serve in future studies as a visible target for novel agents that kill cell-cycle-arrested cells.

  18. MiR-181b regulates cisplatin chemosensitivity and metastasis by targeting TGFβR1/Smad signaling pathway in NSCLC.

    Science.gov (United States)

    Wang, Xiaoyuan; Chen, Xuesong; Meng, Qingwei; Jing, Hu; Lu, Hailing; Yang, Yanmei; Cai, Li; Zhao, Yanbin

    2015-12-01

    MicroRNAs (miRNAs) have been identified as important post-transcriptional regulators involved in various biological and pathological processes of cells, but their underlying mechanisms in chemosensitivity and metastasis have not been fully elucidated. The objective of this study was to identify miR-181b and its mechanism in the chemosensitivity and metastasis of NSCLC. We found that miR-181b expression levels were lower in A549/DDP cells compared with A549 cells. Functional assays showed that the overexpression of miR-181b inhibited proliferation, enhanced chemosensitivity to DDP, attenuated migration and metastatic ability in NSCLC cell lines in vitro and in vivo. TGFβR1 was subsequently identified as a novel functional target of miR-181b. TGFβR1 knockdown revealed similar effects as that of ectopic miR-181b expression, whereas overexpression of TGFβR1 rescued the function of miR-181b-mediated growth, chemosensitivity and metastasis in NSCLC cells. In addition, miR-181b could inactivate the TGFβR1/Smad signaling pathway. We also observed that decreased miR-181b expression and increased TGFβR1 expression were significantly associated with chemosensitivity to DDP and tumor metastasis in NSCLC patients. Consequently, miR-181b functions as a tumor suppressor and has an important role in proliferation, chemosensitivity to DDP and metastasis of NSCLC by targeting TGFβR1/Smad signaling pathway.

  19. Synthetic Smac Peptide Enhances Chemo-sensitivity of Bladder Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Jing WANG; Fuqing ZENG; Liang WANG; Zhaohui ZHU; Guosong JIANG

    2008-01-01

    The effects of synthetic Smac peptide (SmacN7) on chemotherapeutic sensitivity of bladder cancer cells were investigated. SmacN7 penetratin peptide was synthesized and delivered into T24 cells. MTT assay was used to evaluate the viability of T24 cells induced by low-dosage of MMC. Flow cytometry was used to analyze the proportions of apoptosis. Western blot was used to detect the expression of XIAP and Caspase-3. The activity of Caspase-3 was measured and the effect of SmacN7 combined with MMC on T24 cell lines was also determined. The results showed that SmacN7 penetratin peptide could successfully interact with endogenous XIAP, increase the proportions of apoptosis of T24 cell lines induced by low-dosage of MMC in a dose-and time-dependent manner. An obvious down-regulation of XIAP expression and up-regulation of Caspase-3 was identified by Western blot. The activity of Caspase-3 in experimental group was significantly increased as compared with that in the control group. As compared with MMC group, the viability of T24 cells in SmacN7 penetratin peptide + MMC group was markedly decreased to 2.22 and 3.61 folds at 24h and 48h respectively. It was concluded that SmacN7 penetratin peptide could act as a cell-permeable IAP inhibitor, inhibit the proliferation, induce apoptosis and enhance the chemo-sensitivity of bladder cancer cells to MMC. These findings indicate that SmacN7 penetratin peptide may be a very promising ageut for bladder cancer treatment when used in combination with chemotherapy.

  20. Decorin in human oral cancer: A promising predictive biomarker of S-1 neoadjuvant chemosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Kasamatsu, Atsushi, E-mail: kasamatsua@faculty.chiba-u.jp [Department of Oral Science, Graduate School of Medicine, Chiba University, Chiba 260-8670 (Japan); Department of Dentistry and Oral–Maxillofacial Surgery, Chiba University Hospital, Chiba 260-8670 (Japan); Uzawa, Katsuhiro, E-mail: uzawak@faculty.chiba-u.jp [Department of Oral Science, Graduate School of Medicine, Chiba University, Chiba 260-8670 (Japan); Department of Dentistry and Oral–Maxillofacial Surgery, Chiba University Hospital, Chiba 260-8670 (Japan); Minakawa, Yasuyuki; Ishige, Shunsaku; Kasama, Hiroki [Department of Oral Science, Graduate School of Medicine, Chiba University, Chiba 260-8670 (Japan); Endo-Sakamoto, Yosuke; Ogawara, Katsunori [Department of Dentistry and Oral–Maxillofacial Surgery, Chiba University Hospital, Chiba 260-8670 (Japan); Shiiba, Masashi; Takiguchi, Yuichi [Medical Oncology, Graduate School of Medicine, Chiba University, Chiba 260-8670 (Japan); Tanzawa, Hideki [Department of Oral Science, Graduate School of Medicine, Chiba University, Chiba 260-8670 (Japan); Department of Dentistry and Oral–Maxillofacial Surgery, Chiba University Hospital, Chiba 260-8670 (Japan)

    2015-01-30

    Highlights: • DCN is significantly up-regulated in chemoresistant cancer cell lines. • DCN is a key regulator for chemoresistant mechanisms in vitro and in vivo. • DCN predicts the clinical responses to S-1 NAC for patients with oral cancer. - Abstract: We reported previously that decorin (DCN) is significantly up-regulated in chemoresistant cancer cell lines. DCN is a small leucine-rich proteoglycan that exists and functions in stromal and epithelial cells. Accumulating evidence suggests that DCN affects the biology of several types of cancer by directly/indirectly targeting the signaling molecules involved in cell growth, survival, metastasis, and angiogenesis, however, the molecular mechanisms of DCN in chemoresistance and its clinical relevance are still unknown. Here we assumed that DCN silencing cells increase chemosusceptibility to S-1, consisted of tegafur, prodrug of 5-fluorouracil. We first established DCN knockdown transfectants derived from oral cancer cells for following experiments including chemosusceptibility assay to S-1. In addition to the in vitro data, DCN knockdown zenografting tumors in nude mice demonstrate decreasing cell proliferation and increasing apoptosis with dephosphorylation of AKT after S-1 chemotherapy. We also investigated whether DCN expression predicts the clinical responses of neoadjuvant chemotherapy (NAC) using S-1 (S-1 NAC) for oral cancer patients. Immunohistochemistry data in the preoperative biopsy samples was analyzed to determine the cut-off point for status of DCN expression by receiver operating curve analysis. Interestingly, low DCN expression was observed in five (83%) of six cases with complete responses to S-1 NAC, and in one (10%) case of 10 cases with stable/progressive disease, indicating that S-1 chemosensitivity is dramatically effective in oral cancer patients with low DCN expression compared with high DCN expression. Our findings suggest that DCN is a key regulator for chemoresistant mechanisms, and

  1. Effects of hypoxia on expression of a panel of stem cell and chemosensitivity markers in glioblastoma cell line-derived spheroids

    DEFF Research Database (Denmark)

    Kolenda, Jesper; Jensen, Stine Skov; Aaberg-Jessen, Charlotte;

    immunohistochemical panel included hypoxia (HIF-1α, HIF-2α), proliferation (Ki-67) and stem cell (CD133, nestin, podoplanin, Bmi-1, Sox-2) markers as well as markers related to chemosensitivity (MGMT, MDR-1, TIMP-1, Lamp-1). Since spheroids derived in hypoxia were smaller than in normoxia, a set of experiments...... for podoplanin, nestin and TIMP-1 as well as for Ki-67. Hif-2α, Sox-2, MGMT and MDR-1 were not detectable in normoxic and hypoxic U87 spheroids. In conclusion, the expression of tumor stem cell and chemosensitivity markers seems to depend on the oxygen tension suggesting that future development of therapeutic...

  2. Wild type p53 increased chemosensitivity of drug-resistant human hepatocellular carcinoma Be17402 / 5-FU cells

    Institute of Scientific and Technical Information of China (English)

    Yu-xiuLI; Zhi-binLIN; Huan-ranTAN

    2004-01-01

    AIM: To study the effect of wild type (wt) p53 gene transfection on drug resistant human hepatocellular carcinoma(HCC) cells induced by 5-Fluorouracil (5-FU). METHODS: The cytotoxicity of anticancer drugs on Be17402 and Be17402/5-FU cells was assessed using SRB assay, p53 expression was detected at its mRNA level by RT-PCR assay and at its protein level Western blot or immunocytochemistry assay in Be17402/5-FU cells transfected with either control vector or wt p53. AnnexinV-FITC/PI double labeled assay was performed to detect apoptosis. The chemosensitivity of Be17402/5-FU cells transfected with wt p53 was assessed using SRB assay. RESULTS: Be17402/5-FU cells exhibited cross-resistance to vincristine, doxorubicin, paclitaxel, and so on. wt p53 gene transfection upregulated the expression of p53 in Be17402/5-FU cells, wt p53 was able to greatly inhibit cell proliferation and significantly induce apoptosis in Be17402/5-FU cells. Moreover, wt p53 gene transfection increased the chemosensitivity of Be17402/5-FU cells to some anticancer drugs. CONCLUSION: These results indicated that the wt p53 gene transfection not only induced suppression of cell growth, but also increased the sensitivity of Be17402/5-FU cells to 5-FU, vincristine, and doxorubicin.

  3. Increased chemosensitivity and radiosensitivity of human breast cancer cell lines treated with novel functionalized single-walled carbon nanotubes

    Science.gov (United States)

    Jia, Yijun; Weng, Ziyi; Wang, Chuanying; Zhu, Mingjie; Lu, Yunshu; Ding, Longlong; Wang, Yongkun; Cheng, Xianhua; Lin, Qing; Wu, Kejin

    2017-01-01

    Hypoxia is a major cause of treatment resistance in breast cancer. Single-walled carbon nanotubes (SWCNTs) exhibit unique properties that make them promising candidates for breast cancer treatment. In the present study, a new functionalized single-walled carbon nanotube carrying oxygen was synthesized; it was determined whether this material could increase chemosensitivity and radiosensitivity of human breast cancer cell lines, and the underlying mechanisms were investigated. MDA-MB-231 cells growing in folic acid (FA) free medium, MDA-MB-231 cells growing in medium containing FA and ZR-75-1 cells were treated with chemotherapy drugs or radiotherapy with or without tombarthite-modified-FA-chitosan (R-O2-FA-CHI)-SWCNTs under hypoxic conditions, and the cell viability was determined by water-soluble tetrazolium salts-1 assay. The cell surviving fractions were determined by colony forming assay. Cell apoptosis induction was monitored by flow cytometry. Expression of B-cell lymphoma 2 (Bcl-2), survivin, hypoxia-inducible factor 1-α (HIF-1α), multidrug resistance-associated protein 1 (MRP-1), P-glycoprotein (P-gp), RAD51 and Ku80 was monitored by western blotting. The novel synthesized R-O2-FA-CHI-SWCNTs were able to significantly enhance the chemosensitivity and radiosensitivity of human breast cancer cell lines and the material exhibited its expected function by downregulating the expression of Bcl-2, survivin, HIF-1α, P-gp, MRP-1, RAD51 and Ku80.

  4. Tubulin binding cofactor C (TBCC suppresses tumor growth and enhances chemosensitivity in human breast cancer cells

    Directory of Open Access Journals (Sweden)

    Laurier Jean-Fabien

    2010-04-01

    Full Text Available Abstract Background Microtubules are considered major therapeutic targets in patients with breast cancer. In spite of their essential role in biological functions including cell motility, cell division and intracellular transport, microtubules have not yet been considered as critical actors influencing tumor cell aggressivity. To evaluate the impact of microtubule mass and dynamics on the phenotype and sensitivity of breast cancer cells, we have targeted tubulin binding cofactor C (TBCC, a crucial protein for the proper folding of α and β tubulins into polymerization-competent tubulin heterodimers. Methods We developed variants of human breast cancer cells with increased content of TBCC. Analysis of proliferation, cell cycle distribution and mitotic durations were assayed to investigate the influence of TBCC on the cell phenotype. In vivo growth of tumors was monitored in mice xenografted with breast cancer cells. The microtubule dynamics and the different fractions of tubulins were studied by time-lapse microscopy and lysate fractionation, respectively. In vitro sensitivity to antimicrotubule agents was studied by flow cytometry. In vivo chemosensitivity was assayed by treatment of mice implanted with tumor cells. Results TBCC overexpression influenced tubulin fraction distribution, with higher content of nonpolymerizable tubulins and lower content of polymerizable dimers and microtubules. Microtubule dynamicity was reduced in cells overexpressing TBCC. Cell cycle distribution was altered in cells containing larger amounts of TBCC with higher percentage of cells in G2-M phase and lower percentage in S-phase, along with slower passage into mitosis. While increased content of TBCC had little effect on cell proliferation in vitro, we observed a significant delay in tumor growth with respect to controls when TBCC overexpressing cells were implanted as xenografts in vivo. TBCC overexpressing variants displayed enhanced sensitivity to

  5. Metuzumab enhanced chemosensitivity and apoptosis in non-small cell lung carcinoma

    Science.gov (United States)

    Feng, Fei; Wang, Bin; Sun, Xiuxuan; Zhu, Yumeng; Tang, Hao; Nan, Gang; Wang, Lijuan; Wu, Bo; Huhe, Muren; Liu, Shuangshuang; Diao, Tengyue; Hou, Rong; Zhang, Yang; Zhang, Zheng

    2017-01-01

    ABSTRACT Targeted therapeutics is used as an alternative treatment of non-small cell lung cancer (NSCLC); however, treatment effect is far from being satisfactory, and therefore identification of new targets is needed. We have previously shown that metuzumab inhibit tumor growth in vivo. The present study was performed to investigate the anti-tumor efficacy of metuzumab combined with gemcitabine and cisplatin (GP), paclitaxel and cisplatin (TP) or navelbine and cisplatin (NP) regimens in multiple NSCLC cell lines. Our results demonstrate that, in comparison to single agent metuzumab or GP treated cells, metuzumab combined with GP display inhibitory effects on tumor growth. Furthermore, we found that metuzumab elevated the sensitivity of cell lines to gemcitabine, which was identified by MTT assay. Flow cytometric analysis showed that metuzumab combined with gemcitabine (GEM) treatment led to an obvious G1 arrest and an elevated apoptosis in A549, NCI-H460 and NCI-H520 cells. Western blot analysis also demonstrated a significantly reduced level of cyclin D1, Bcl-2, and an obviously increase level of Bax and full-length caspase-3 in A549, NCI-H460 and NCI-H520 cells treated with metuzumab/gemcitabine combination in comparison with single agent treated cells. In addition, metuzumab/gemcitabine treated A549, NCI-H460 and NCI-H520 cells also demonstrated a significantly increase in deoxycytidine kinase (dCK) protein level compared with single agent metuzumab or gemcitabine treated cells. Xenograft models also demonstrated that this metuzumab/gemcitabine combination led to upregulation of dCK. Taken together, the mechanisms of metuzumab combined with GP repress tumor growth were that the combined treatment significantly inhibited the tumor cell proliferation, apoptosis and cell cycle in vitro and in vivo and at least partially by induction of dCK expression. Our results suggested that metuzumab could significantly enhance chemosensitivity of human NSCLC cells to

  6. Up-regulation of Raf kinase inhibitor protein enhances chemosensitivity of cervical cancer cell

    Institute of Scientific and Technical Information of China (English)

    Xiao Chu; Xinqiang Ji; Mingcui Wang; Wenqing Zhang; Hui Ou; Chong Li

    2014-01-01

    Objective:The purpose of the study is to investigate the ef ects of up-regulation of Raf kinase inhibitor protein (RKlP) on the chemosensitivity of cervical cancer Hela cells. Methods:Eukaryotic expression plasmid pcDNA3.1(+)-ssRKIP containing human overal length RKIPcDNA was transfected into cervical cancer Hela cellby lipofectin assay, establishing a stable cellline containing a target gene by G418. Expression of RKIP in Hela cells was measured by Western blot analysis. After treatment with cisplatin of dif erent concentrations and intervals of time, the ef ect of RKIP on the proliferation of Hela cells was evaluated by MTT method. The flow cytometry was used to investigate whether the RKIP could inhibit apoptosis in Hela cells induced by cisplatin. Results:The expression of RKIP in Hela cells transfected with pcDNA3.1-ssRKIP was increased obviously. After dif erent concentrations of cisplatin treatment cells for 24, 48 and 72 h, the growth inhibition rate in Hela cells transfected with pcDNA3.1-ssRKIP was significantly higher than in control cells (P<0.05). With 5μg/mL cisplatin treatment for 24 h, pcDNA3.1-ssRKIP-transfected Hela cells had an obviously higher percentage of apoptosis (23.2 ± 0.24)%than non-transfected cells (12.4 ± 0.31)%and empty vector-transfected cells (13.4 ± 0.47)%. Without treatment of cisplatin, the percentage of apoptosis for Hela cells transfected with pcDNA3.1-ssRKIP was (5.7 ± 0.12)%, which was stil higher than those of the non-transfected cells (2.9 ± 0.21)%and empty vector-transfected cells (3 ± 0.08)%. Conclusion:Higher expres-sion of RKIP gene can improve chemosensitivitv of cervical cancer Hela cells to cisplatin.

  7. Chemosensitizing acridones: in vitro calmodulin dependent cAMP phosphodiesterase inhibition, docking, pharmacophore modeling and 3D QSAR studies.

    Science.gov (United States)

    Rajendra Prasad, V V S; Deepak Reddy, G; Appaji, D; Peters, G J; Mayur, Y C

    2013-03-01

    Calmodulin inhibitors have proved to play a significant role in sensitizing MDR cancer cells by interfering with cellular drug accumulation. The present investigation focuses on the evaluation of in vitro inhibitory efficacy of chloro acridones against calmodulin dependent cAMP phosphodiesterase (PDE1c). Moreover, molecular docking of acridones was performed with PDE1c in order to identify the possible protein ligand interactions and results thus obtained were compared with in vitro data. In addition an efficient pharmacophore model was developed from a set of 38 chemosensitizing acridones effective against doxorubicin resistant (HL-60/DX) cancer cell lines. Pharmacophoric features such as one hydrogen bond acceptor, one hydrophobic region, a positive ion group and three aromatic rings i.e., AHPRRR have been identified. Ligand based 3D-QSAR was also performed by employing partial least square regression analysis.

  8. Suppression of bcl-2 Gene by RNA Interference Increases Chemosensitivity to Cisplatin in Nasopharyngeal Carcinoma Cell Line CNE1

    Institute of Scientific and Technical Information of China (English)

    Zhi-Hua YIN; Cai-Ping REN; Feng LI; Xu-Yu YANG; Hui LI; Ming ZHAO; Kai-Tai YAO

    2004-01-01

    To explore the effect of suppressing BCL-2 expression using RNA interference (RNAi) technique in nasopharyngeal carcinoma cell line CNE1. CNE1 cell lines stably expressing shRNAs targeted bcl-2 and GL3 gene were established and gene expression inhibition was assessed by Western blotting analysis. The effect of suppressing bcl-2 by RNAi on cell growth was studied, the apoptosis induction and the sensitization of CNE 1 cells to cisplatin were quantified by MTT assay and flow cytometry. The results showed that: stable transfection of CNE 1 cells with vectors expressing shRNAs against bcl-2 decreased the expression of BCL-2 protein; suppression of BCL-2 expression did not affect cell proliferation but could increase the chemosensitivity to cisplatin in CNE1 cells. This will help physicians to make some clinical trials of gene therapy on nasopharyngeal carcinoma by RNAi.

  9. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

    Science.gov (United States)

    Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P.; Fuessel, Susanne

    2014-10-01

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel

  10. MEK2 is a prognostic marker and potential chemo-sensitizing target for glioma patients undergoing temozolomide treatment.

    Science.gov (United States)

    He, Hua; Yao, Maojin; Zhang, Wenhao; Tao, Bangbao; Liu, Feili; Li, Shu; Dong, Yan; Zhang, Chenran; Meng, Yicheng; Li, Yuxin; Hu, Guohan; Luo, Chun; Zong, Hui; Lu, Yicheng

    2016-09-01

    Although temozolomide (TMZ) is the first-line chemotherapeutic agent for glioblastoma, it is often non-curative due to drug resistance. To overcome the resistance of glioblastoma cells to TMZ, it is imperative to identify prognostic markers for outcome prediction and to develop chemo-sensitizing agents. Here, the gene expression profiles of TMZ-resistant and TMZ-sensitive samples were compared by microarray analysis, and mitogen-activated protein kinase kinase 2 (MEK2) was upregulated specifically in resistant glioma cells but not in sensitive tumor cells or non-tumor tissues. Moreover, a comprehensive analysis of patient data revealed that the increased level of MEK2 expression correlated well with the advancement of glioma grade and worse prognosis in response to TMZ treatment. Furthermore, reducing the level of MEK2 in U251 glioma cell lines or xenografted glioma models through shRNA-mediated gene knockdown inhibited cell proliferation and enhanced the sensitivity of cells toward TMZ treatment. Further analysis of tumor samples from glioma patients by real-time PCR indicated that an increased MEK2 expression level was closely associated with the activation of many drug resistance genes. Finally, these resistance genes were downregulated after MEK2 was silenced in vitro, suggesting that the mechanism of MEK2-induced chemo-resistance could be mediated by the transcriptional activation of these resistance genes. Collectively, our data indicated that the expression level of MEK2 could serve as a prognostic marker for glioma chemotherapy and that MEK2 antagonists can be used as chemo-sensitizers to enhance the treatment efficacy of TMZ.

  11. RASSF1A expression inhibits cell growth and enhances cell chemosensitivity to mitomycin in BEL-7402 hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    GUAN Hong-geng; XUE Wan-jiang; QIAN Hai-xin; ZHOU Xiao-jun; QIN Lei; LAN Jing

    2009-01-01

    Background The antitumor role of Ras association domain family 1A (RASSFIA) gene and its potential molecular mechanisms are not well understood. The objective of this study was to observe the antitumor ability of RASSFIA in hepatoceliular carcinoma, and study the mechanisms of cell apoptosis induced by RASSFIA.Methods After stably transfecting a RASSF1A (wild-type or mutant) expression vector into the BEL-7402 hepatocellular carcinoma cell line, RT-PCR and Westem blotting was used to detect the RASSF1A expression levels in recombinant cells. The effects of wild-type RASSF1A on cell growth were observed in vitro by analyzing cell proliferation rate, cell colony formation, and in vivo by analyzing tumorigenesis in nude mice. In addition, the effect of RASSF1A gene expression on the chemosensitivity of human hepatocellular carcinoma cells to antitumor drugs was examined by inhibition of cell proliferation and the percentage of apoptotic cells.Results Wild-type RASSF1A, not the mutant, suppressed cell growth in vitro and in vivo. Re-expression of wild-type RASSF1A could enhance the inhibition of cell proliferation and the percentage of apoptotic cells following cell treatment with mitomycin, but had no significant effect when combined with adriamycin, etoposide, 5-fluorouracil and cisplatJn treatment.Conclusion Wild-type RASSF1A inhibits cell growth and enhances cell chemosensitivity to mitomycin in hepatocellular carcinoma, suggesting that RASSF1A may serve as a new target for gene therapy in hepatocellular carcinoma patients.

  12. Chemosensitivity assay in mice prostate tumor: Preliminary report of flow cytometry, DNA fragmentation, ion ratiometric methods of anti-neoplastic drug monitoring

    Directory of Open Access Journals (Sweden)

    Kline Richard

    2004-03-01

    Full Text Available Abstract Flow cytometry, DNA fragmentation, ion ratiomateric analysis and NMR peaks characterized drug chemosensitivity of antineoplastic drugs. Hypotheses were: 1. The chemosensitive effect of different cancer cell lines is characteristic; 2. DNA fragmentation, ion ratiometric analysis suggest apoptosis status of tumor cells. Methods PC-3 cell lines were compared with DU-145, LNCaP cell lines in culture for the [Na]i and [Ca]i ion sensing dyes, cell death, NMR peaks and apoptosis staining for chemotherapeutic action of different drugs. Results DNA fragmentation, ratiometric ions and fluorescence endlabelling plots were characteristic for cell lines and drug response. 31P-23Na NMR spectra showed characteristic high phospho-choline and sodium peaks. Conclusion Flow cytometry, DNA fragmentation, ion ratiometric methods and NMR peaks indicated apoptosis and offered in vivo drug monitoring method.

  13. Chemosensitivity of human small cell carcinoma of the lung detected by flow cytometric DNA analysis of drug-induced cell cycle perturbations in vitro

    DEFF Research Database (Denmark)

    Engelholm, S A; Spang-Thomsen, M; Vindeløv, L L

    1986-01-01

    A method based on detection of drug-induced cell cycle perturbation by flow cytometric DNA analysis has previously been described in Ehrlich ascites tumors as a way to estimate chemosensitivity. The method is extended to test human small-cell carcinoma of the lung. Three tumors with different...... sensitivities to melphalan in nude mice were used. Tumors were disaggregated by a combined mechanical and enzymatic method and thereafter have incubated with different doses of melphalan. After incubation the cells were plated in vitro on agar, and drug induced cell cycle changes were monitored by flow...... cytometric DNA analysis. Melphalan produced a dose-related S phase accumulation in the two sensitive tumors, whereas no changes in the cell cycle distribution were found in the resistant tumor. The size of S phase accumulation correlated to the chemosensitivity in vivo. For low concentrations of melphalan...

  14. Gamma-Secretase Inhibitors Abrogate Oxaliplatin-Induced Activation of the Notch-1 Signaling Pathway in Colon Cancer Cells Resulting in Enhanced Chemosensitivity

    OpenAIRE

    Meng, Raymond D.; Shelton, Christopher C.; Li, Yue-Ming; Qin, Li-Xuan; Paty, Philip B.; Schwartz, Gary K.

    2009-01-01

    Because Notch signaling is implicated in colon cancer tumorigenesis and protects from apoptosis by inducing pro-survival targets, it was hypothesized that inhibition of Notch signaling with gamma-secretase inhibitors (GSIs) may enhance the chemosensitivity of colon cancer cells. We first show that the Notch-1 receptor and its downstream target Hes-1 is upregulated with colon cancer progression, similar to other genes involved in chemoresistance. We then report that chemotherapy induces Notch-...

  15. RNAi-mediated silencing of CD147 inhibits tumor cell proliferation, invasion and increases chemosensitivity to cisplatin in SGC7901 cells in vitro

    Directory of Open Access Journals (Sweden)

    Zhu Chan

    2010-06-01

    Full Text Available Abstract Background CD147 is a widely distributed cell surface glycoprotein that belongs to the Ig superfamily. CD147 has been implicated in numerous physiological and pathological activities. Enriched on the surface of many tumor cells, CD147 promotes tumor growth, invasion, metastasis and angiogenesis and confers resistance to some chemotherapeutic drugs. In this study, we investigated the possible role of CD147 in the progression of gastric cancer. Methods Short hairpin RNA (shRNA expressing vectors targeting CD147 were constructed and transfected into human gastric cancer cells SGC7901 and CD147 expression was monitored by quantitative realtime RT-PCR and Western blot. Cell proliferation, the activities of MMP-2 and MMP-9, the invasive potential and chemosensitivity to cisplatin of SGC7901 cells were determined by MTT, gelatin zymography, Transwell invasion assay and MTT, respectively. Results Down-regulation of CD147 by RNAi approach led to decreased cell proliferation, MMP-2 and MMP-9 activities and invasive potential of SGC7901 cells as well as increased chemosensitivity to cisplatin. Conclusion CD147 involves in proliferation, invasion and chemosensitivity of human gastric cancer cell line SGC7901, indicating that CD147 may be a promising therapeutic target for gastric cancer.

  16. [Knock-down of apollon gene by antisense oligodeoxynucleotide inhibits the proliferation of Lovo cells and enhances chemo-sensitivity].

    Science.gov (United States)

    He, Jin-hua; Zhang, Xiao-ying; Wu, Feng-yun; Liao, Xiao-li; Wang, Wei; Jiang, Jian-wei

    2011-02-01

    In this study, the effects of apollon antisense oligodeoxynucleotide (ASODN) on the proliferation and apoptosis of human Lovo cells in vitro were investigated. Apollon ASODN was incubated with human colorectal Lovo cells for 48 h, the proliferation inhibition and the clone forming rates were detected by WST method and clone formation assay, respectively. The expression of apollon mRNA was analyzed by real time fluorescent quantitative reverse transcription polymerase chain reaction. The percentage of apoptotic cells and cell cycle distribution were determined by flow cytometry. The morphology of apoptotic cells was examined by fluorescence microscope. Lovo cells incubated with apollon ASODN combined with 5-fluorouracil (5-FU), cisplatin (DDP) or epirubicin (EPI) of different concentrations, cell proliferation inhibition rates were detected with WST method and IC50 was calculated. It was found that ASODN targeting apollon gene could all suppress the growth of Lovo cells and induce apoptosis of these cells significantly (P 5-FU, DDP and EPI on Lovo cells combined with apollon ASODN (0.08 micromol x L(-1)) were enhanced independently compared with single 5-FU, DDP and EPI groups, and the sensitivity enhanced about 2.58, 4.47, and 5.33 times respectively. It can be concluded that ASODN targeting apollon can suppress the expression of apollon mRNA, and inhibit the proliferation, induce apoptosis, arrest cell cycle at S phase of colorectal cancer Lovo cells in vitro and enhance the chemo-sensitivity to 5-FU, DDP and EPI.

  17. Overexpression of human sperm protein 17 increases migration and decreases the chemosensitivity of human epithelial ovarian cancer cells

    Directory of Open Access Journals (Sweden)

    Huang Wen-bin

    2009-09-01

    Full Text Available Abstract Background Most deaths from ovarian cancer are due to metastases that are resistant to conventional therapies. But the factors that regulate the metastatic process and chemoresistance of ovarian cancer are poorly understood. In the current study, we investigated the aberrant expression of human sperm protein 17 (HSp17 in human epithelial ovarian cancer cells and tried to analyze its influences on the cell behaviors like migration and chemoresistance. Methods Immunohistochemistry and immunocytochemistry were used to identify HSp17 in paraffin embedded ovarian malignant tumor specimens and peritoneal metastatic malignant cells. Then we examined the effect of HSp17 overexpression on the proliferation, migration, and chemoresistance of ovarian cancer cells to carboplatin and cisplatin in a human ovarian carcinoma cell line, HO8910. Results We found that HSp17 was aberrantly expressed in 43% (30/70 of the patients with primary epithelial ovarian carcinomas, and in all of the metastatic cancer cells of ascites from 8 patients. The Sp17 expression was also detected in the metastatic lesions the same as in ovarian lesions. None of the 7 non-epithelial tumors primarily developed in the ovaries was immunopositive for HSp17. Overexpression of HSp17 increased the migration but decreased the chemosensitivity of ovarian carcinoma cells to carboplatin and cisplatin. Conclusion HSp17 is aberrantly expressed in a significant proportion of epithelial ovarian carcinomas. Our results strongly suggest that HSp17 plays a role in metastatic disease and resistance of epithelial ovarian carcinoma to chemotherapy.

  18. Prenylated Chalcone 2 Acts as an Antimitotic Agent and Enhances the Chemosensitivity of Tumor Cells to Paclitaxel.

    Science.gov (United States)

    Fonseca, Joana; Marques, Sandra; Silva, Patrícia M A; Brandão, Pedro; Cidade, Honorina; Pinto, Madalena M; Bousbaa, Hassan

    2016-07-29

    We previously reported that prenylated chalcone 2 (PC2), the O-prenyl derivative (2) of 2'-hydroxy-3,4,4',5,6'-pentamethoxychalcone (1), induced cytotoxicity of tumor cells via disruption of p53-MDM2 interaction. However, the cellular changes through which PC2 exerts its cytotoxic activity and its antitumor potential, remain to be addressed. In the present work, we aimed to (i) characterize the effect of PC2 on mitotic progression and the underlying mechanism; and to (ii) explore this information to evaluate its ability to sensitize tumor cells to paclitaxel in a combination regimen. PC2 was able to arrest breast adenocarcinoma MCF-7 and non-small cell lung cancer NCI-H460 cells in mitosis. All mitosis-arrested cells showed collapsed mitotic spindles with randomly distributed chromosomes, and activated spindle assembly checkpoint. Live-cell imaging revealed that the compound induced a prolonged delay (up to 14 h) in mitosis, culminating in massive cell death by blebbing. Importantly, PC2 in combination with paclitaxel enhanced the effect on cell growth inhibition as determined by cell viability and proliferation assays. Our findings demonstrate that the cytotoxicity induced by PC2 is mediated through antimitotic activity as a result of mitotic spindle damage. The enhancement effects of PC2 on chemosensitivity of cancer cells to paclitaxel encourage further validation of the clinical potential of this combination.

  19. Knockdown of astrocyte elevated gene-1 inhibits proliferation and enhancing chemo-sensitivity to cisplatin or doxorubicin in neuroblastoma cells

    Directory of Open Access Journals (Sweden)

    Xie Li

    2009-02-01

    Full Text Available Abstract Background Astrocyte elevated gene-1 (AEG-1 was originally characterized as a HIV-1-inducible gene in primary human fetal astrocyte. Recent studies highlight a potential role of AEG-1 in promoting tumor progression and metastasis. The aim of this study was to investigate if AEG-1 serves as a potential therapeutic target of human neuroblastoma. Methods We employed RNA interference to reduce AEG-1 expression in human neuroblastoma cell lines and analyzed their phenotypic changes. Results We found that the knockdown of AEG-1 expression in human neuroblastoma cells significantly inhibited cell proliferation and apoptosis. The specific downregulation induced cell arrest in the G0/G1 phase of cell cycle. In the present study, we also observed a significant enhancement of chemo-sensitivity to cisplatin and doxorubicin by knockdown of AEG-1. Conclusion Our study suggests that overexpressed AEG-1 enhance the tumorogenic properties of neuroblastoma cells. The inhibition of AEG-1 expression could be a new adjuvant therapy for neuroblastoma.

  20. Induction of autophagy by valproic acid enhanced lymphoma cell chemosensitivity through HDAC-independent and IP3-mediated PRKAA activation.

    Science.gov (United States)

    Ji, Meng-Meng; Wang, Li; Zhan, Qin; Xue, Wen; Zhao, Yan; Zhao, Xia; Xu, Peng-Peng; Shen, Yang; Liu, Han; Janin, Anne; Cheng, Shu; Zhao, Wei-Li

    2015-01-01

    Autophagy is closely related to tumor cell sensitivity to anticancer drugs. The HDAC (histone deacetylase) inhibitor valproic acid (VPA) interacted synergistically with chemotherapeutic agents to trigger lymphoma cell autophagy, which resulted from activation of AMPK (AMP-activated protein kinase) and inhibition of downstream MTOR (mechanistic target of rapamycin [serine/threonine kinase]) signaling. In an HDAC-independent manner, VPA potentiated the effect of doxorubicin on lymphoma cell autophagy via reduction of cellular inositol 1,4,5 trisphosphate (IP3), blockade of calcium into mitochondria and modulation of PRKAA1/2-MTOR cascade. In murine xenograft models established with subcutaneous injection of lymphoma cells, dual treatment of VPA and doxorubicin initiated IP3-mediated calcium depletion and PRKAA1/2 activation, induced in situ autophagy and efficiently retarded tumor growth. Aberrant genes involving mitochondrial calcium transfer were frequently observed in primary tumors of lymphoma patients. Collectively, these findings suggested an HDAC-independent chemosensitizing activity of VPA and provided an insight into the clinical application of targeting autophagy in the treatment of lymphoma.

  1. Silibinin suppresses NPM-ALK, potently induces apoptosis and enhances chemosensitivity in ALK-positive anaplastic large cell lymphoma.

    Science.gov (United States)

    Molavi, Ommoleila; Samadi, Nasser; Wu, Chengsheng; Lavasanifar, Afsaneh; Lai, Raymond

    2016-05-01

    Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK), an oncogenic fusion protein carrying constitutively active tyrosine kinase, is known to be central to the pathogenesis of ALK-positive anaplastic large cell lymphoma (ALK+ALCL). Here, it is reported that silibinin, a non-toxic naturally-occurring compound, potently suppressed NPM-ALK and effectively inhibited the growth and soft agar colony formation of ALK+ALCL cells. By western blots, it was found that silibinin efficiently suppressed the phosphorylation/activation of NPM-ALK and its key substrates/downstream mediators (including STAT3, MEK/ERK and Akt) in a time- and dose-dependent manner. Correlating with these observations, silibinin suppressed the expression of Bcl-2, survivin and JunB, all of which are found to be upregulated by NPM-ALK and pathogenetically important in ALK+ALCL. Lastly, silibinin augmented the chemosensitivity of ALK+ALCL cells to doxorubicin, particularly the small cell sub-set expressing the transcriptional activity of Sox2, an embryonic stem cell marker. To conclude, the findings suggest that silibinin might be useful in treating ALK+ALCL.

  2. Prenylated Chalcone 2 Acts as an Antimitotic Agent and Enhances the Chemosensitivity of Tumor Cells to Paclitaxel

    Directory of Open Access Journals (Sweden)

    Joana Fonseca

    2016-07-01

    Full Text Available We previously reported that prenylated chalcone 2 (PC2, the O-prenyl derivative (2 of 2′-hydroxy-3,4,4′,5,6′-pentamethoxychalcone (1, induced cytotoxicity of tumor cells via disruption of p53-MDM2 interaction. However, the cellular changes through which PC2 exerts its cytotoxic activity and its antitumor potential, remain to be addressed. In the present work, we aimed to (i characterize the effect of PC2 on mitotic progression and the underlying mechanism; and to (ii explore this information to evaluate its ability to sensitize tumor cells to paclitaxel in a combination regimen. PC2 was able to arrest breast adenocarcinoma MCF-7 and non-small cell lung cancer NCI-H460 cells in mitosis. All mitosis-arrested cells showed collapsed mitotic spindles with randomly distributed chromosomes, and activated spindle assembly checkpoint. Live-cell imaging revealed that the compound induced a prolonged delay (up to 14 h in mitosis, culminating in massive cell death by blebbing. Importantly, PC2 in combination with paclitaxel enhanced the effect on cell growth inhibition as determined by cell viability and proliferation assays. Our findings demonstrate that the cytotoxicity induced by PC2 is mediated through antimitotic activity as a result of mitotic spindle damage. The enhancement effects of PC2 on chemosensitivity of cancer cells to paclitaxel encourage further validation of the clinical potential of this combination.

  3. VEGFR3 Inhibition Chemosensitizes Ovarian Cancer Stemlike Cells through Down-Regulation of BRCA1 and BRCA2

    Directory of Open Access Journals (Sweden)

    Jaeyoung Lim

    2014-04-01

    Full Text Available In ovarian cancer, loss of BRCA gene expression in tumors is associated with improved response to chemotherapy and increased survival. A means to pharmacologically downregulate BRCA gene expression could improve the outcomes of patients with BRCA wild-type tumors. We report that vascular endothelial growth factor receptor 3 (VEGFR3 inhibition in ovarian cancer cells is associated with decreased levels of both BRCA1 and BRCA2. Inhibition of VEGFR3 in ovarian tumor cells was associated with growth arrest. CD133+ ovarian cancer stemlike cells were preferentially susceptible to VEGFR3-mediated growth inhibition. VEGFR3 inhibition–mediated down-regulation of BRCA gene expression reversed chemotherapy resistance and restored chemosensitivity in resistant cell lines in which a BRCA2 mutation had reverted to wild type. Finally, we demonstrate that tumor-associated macrophages are a primary source of VEGF-C in the tumor microenvironment. Our studies suggest that VEGFR3 inhibition may be a pharmacologic means to downregulate BRCA genes and improve the outcomes of patients with BRCA wild-type tumors.

  4. Curcumin, the golden spice from Indian saffron, is a chemosensitizer and radiosensitizer for tumors and chemoprotector and radioprotector for normal organs.

    Science.gov (United States)

    Goel, Ajay; Aggarwal, Bharat B

    2010-01-01

    Curcumin (diferuloylmethane), the yellow pigment in Indian saffron (Curcuma longa; also called turmeric, haldi, or haridara in the East and curry powder in the West), has been consumed by people for centuries as a dietary component and for a variety of proinflammatory ailments. Extensive research within the last decade in cell culture and in rodents has revealed that curcumin can sensitize tumors to different chemotherapeutic agents including doxorubicin, 5-FU, paclitaxel, vincristine, melphalan, butyrate, cisplatin, celecoxib, vinorelbine, gemcitabine, oxaliplatin, etoposide, sulfinosine, thalidomide, and bortezomib. Chemosensitization has been observed in cancers of the breast, colon, pancreas, gastric, liver, blood, lung, prostate, bladder, cervix, ovary, head and neck, and brain and in multiple myeloma, leukemia, and lymphoma. Similar studies have also revealed that this agent can sensitize a variety of tumors to gamma radiation including glioma, neuroblastoma, cervical carcinoma, epidermal carcinoma, prostate cancer, and colon cancer. How curcumin acts as a chemosensitizer and radiosensitizer has also been studied extensively. For example, it downregulates various growth regulatory pathways and specific genetic targets including genes for NF-κB, STAT3, COX2, Akt, antiapoptotic proteins, growth factor receptors, and multidrug-resistance proteins. Although it acts as a chemosensitizer and radiosensitizer for tumors in some cases, curcumin has also been shown to protect normal organs such as liver, kidney, oral mucosa, and heart from chemotherapy and radiotherapy-induced toxicity. The protective effects of curcumin appear to be mediated through its ability to induce the activation of NRF2 and induce the expression of antioxidant enzymes (e.g., hemeoxygenase-1, glutathione peroxidase, modulatory subunit of gamma-glutamyl-cysteine ligase, and NAD(P)H:quinone oxidoreductase 1, increase glutathione (a product of the modulatory subunit of gamma

  5. PARP inhibitor increases chemosensitivity by upregulating miR-664b-5p in BRCA1-mutated triple-negative breast cancer.

    Science.gov (United States)

    Song, Wei; Tang, Lin; Xu, Yumei; Xu, Jing; Zhang, Wenwen; Xie, Hui; Wang, Shui; Guan, Xiaoxiang

    2017-02-08

    Emerging evidence has shown that adding poly(ADP-ribose) polymerase (PARP) inhibitors to chemotherapy regimens is superior to the control regimens alone in BRCA1-mutated triple-negative breast cancer (TNBC) patients, but their underlying mechanisms have not been fully elucidated. In this study, using miRNA microarray analysis of two BRCA1-mutated TNBC cell lines, we found that miR-664b-5p expression was increased after adding a PARP inhibitor, olaparib, to a carboplatin (CBP) plus gemcitabine (GEM) therapy regimen. Functional assays showed miR-664b-5p overexpression inhibited proliferation, migration and invasion in BRCA1-mutated TNBC cells. CCNE2 was identified as a novel functional target of miR-664b-5p, and CCNE2 knockdown revealed effects similar to those observed with miR-664b-5p overexpression. Both CCNE2 knockdown and miR-664b-5p overexpression significantly increased the chemosensitivity of BRCA1-mutated TNBC cells. In addition, in vivo studies indicated that miR-664b-5p inhibited tumour growth compared with the control in tumour xenograft models, and we also found that CCNE2 expression was inversely correlated with miR-664b-5p expression in 90 TNBC patient samples. In conclusion, miR-664b-5p functions as a tumour suppressor and has an important role in the regulation of PARP inhibitors to increase chemosensitivity by targeting CCNE2. This may be one of the possible mechanisms by which PARP inhibitors increase chemosensitivity in BRCA1-mutated TNBC.

  6. Knockdown of dual specificity phosphatase 4 enhances the chemosensitivity of MCF-7 and MCF-7/ADR breast cancer cells to doxorubicin

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yu; Du, Feiya; Chen, Wei; Yao, Minya; Lv, Kezhen; Fu, Peifen, E-mail: fupeifendoczju@163.com

    2013-12-10

    Background: Breast cancer is the major cause of cancer-related deaths in females world-wide. Doxorubicin-based therapy has limited efficacy in breast cancer due to drug resistance, which has been shown to be associated with the epithelial-to-mesenchymal transition (EMT). However, the molecular mechanisms linking the EMT and drug resistance in breast cancer cells remain unclear. Dual specificity phosphatase 4 (DUSP4), a member of the dual specificity phosphatase family, is associated with cellular proliferation and differentiation; however, its role in breast cancer progression is controversial. Methods: We used cell viability assays, Western blotting and immunofluorescent staining, combined with siRNA interference, to evaluate chemoresistance and the EMT in MCF-7 and adriamycin-resistant MCF-7/ADR breast cancer cells, and investigate the underlying mechanisms. Results: Knockdown of DUSP4 significantly increased the chemosensitivity of MCF-7 and MCF-7/ADR breast cancer cells to doxorubicin, and MCF-7/ADR cells which expressed high levels of DUSP4 had a mesenchymal phenotype. Furthermore, knockdown of DUSP4 reversed the EMT in MCF-7/ADR cells, as demonstrated by upregulation of epithelial biomarkers and downregulation of mesenchymal biomarkers, and also increased the chemosensitivity of MCF-7/ADR cells to doxorubicin. Conclusions: DUSP4 might represent a potential drug target for inhibiting drug resistance and regulating the process of the EMT during the treatment of breast cancer. - Highlights: • We used different technologies to prove our conclusion. • DUSP4 knockdown increased doxorubicin chemosensitivity in breast cancer cells. • DUSP4 is a potential target for combating drug resistance in breast cancer. • DUSP4 is a potential target for regulating the EMT in breast cancer.

  7. PARP inhibitor increases chemosensitivity by upregulating miR-664b-5p in BRCA1-mutated triple-negative breast cancer

    Science.gov (United States)

    Song, Wei; Tang, Lin; Xu, Yumei; Xu, Jing; Zhang, Wenwen; Xie, Hui; Wang, Shui; Guan, Xiaoxiang

    2017-01-01

    Emerging evidence has shown that adding poly(ADP-ribose) polymerase (PARP) inhibitors to chemotherapy regimens is superior to the control regimens alone in BRCA1-mutated triple-negative breast cancer (TNBC) patients, but their underlying mechanisms have not been fully elucidated. In this study, using miRNA microarray analysis of two BRCA1-mutated TNBC cell lines, we found that miR-664b-5p expression was increased after adding a PARP inhibitor, olaparib, to a carboplatin (CBP) plus gemcitabine (GEM) therapy regimen. Functional assays showed miR-664b-5p overexpression inhibited proliferation, migration and invasion in BRCA1-mutated TNBC cells. CCNE2 was identified as a novel functional target of miR-664b-5p, and CCNE2 knockdown revealed effects similar to those observed with miR-664b-5p overexpression. Both CCNE2 knockdown and miR-664b-5p overexpression significantly increased the chemosensitivity of BRCA1-mutated TNBC cells. In addition, in vivo studies indicated that miR-664b-5p inhibited tumour growth compared with the control in tumour xenograft models, and we also found that CCNE2 expression was inversely correlated with miR-664b-5p expression in 90 TNBC patient samples. In conclusion, miR-664b-5p functions as a tumour suppressor and has an important role in the regulation of PARP inhibitors to increase chemosensitivity by targeting CCNE2. This may be one of the possible mechanisms by which PARP inhibitors increase chemosensitivity in BRCA1-mutated TNBC. PMID:28176879

  8. Associations between gene polymorphisms of thymidylate synthase with its protein expression and chemosensitivity to 5-fluorouracil in pancreatic carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qiang; ZHAO Yu-pei; LIAO Quan; HU Ya; XU Qiang; ZHOU Li; SHU Hong

    2011-01-01

    Background Thymidylate synthase (TS) is a key regulatory enzyme for de novo DNA synthesis.TS activity is also an important determinant of the response to chemotherapy with fluoropyrimidine prodrugs,and its expression may be affected by gene polymorphisms.In this study,we investigated the associations between polymorphisms of the TS gene and its protein expression,and the implications on the efficacy of 5-fluorouracil (5-FU) in pancreatic cancer cells.Methods Genotypes based on the 28-bp TS tandem repeat for pancreatic cell lines were determined by electrophoretic analysis of PCR products.A single nucleotide polymorphism (SNP) at nucleotide 12 of the second 28-bp repeat of the 3R allele was determined by nucleotide sequencing.The chemosensitivity of pancreatic carcinoma cells to 5-FU in vitro was evaluated using Cell Counting Kit-8 (CCK-8).TS protein expression was analyzed by Western blotting.Results Seven pancreatic carcinoma cell lines had different genotypes in terms of the 28-bp TS tandem repeat,as follows:homozygous 2R/2R (T3M4 and BxPC-3 cells),heterozygous 2R/3R (AsPC-1,Capan-1,and SU86.86),and homozygous 3R/3R (PANC-1 and COLO357).The optical density ratio of genotypes 3R/3R,2R/2R and 2R/3R was 1.393±0.374,0.568±0.032 and 0.561±0.056,respectively.Cells with the 2R/3R or 3R/3R genotypes were further analyzed for the G to C SNP at nucleotide 12 of the second 28-bp repeat of the 3R allele,yielding heterozygous 2R/3Rc (AsPC-1,Capan-1,and SU86.86),homozygous 3Rg/3Rg (COLO357) and homozygous 3Rc/3Rc (PANC-1).The optical density ratio of homozygous 3Rg/3Rg cells and homozygous 3Rc/3Rc cells was 1.723±0.062 and 1.063±0.134,respectively,and this difference was statistically significant (P <0.05).Cells with the 2R/2R and 2R/3R genotypes of TS were hypersensitive to 5-FU in vitro as compared with those with the 3R/3R cells.Conclusions Polymorphisms in the TS gene influenced its protein expression and affected sensitivity of 5-FU in seven pancreatic cancer cell

  9. Antitumor activity of zoledronic acid in primary breast cancer cells determined by the ATP tumor chemosensitivity assay

    Directory of Open Access Journals (Sweden)

    Fehm Tanja

    2012-07-01

    Full Text Available Abstract Background The NeoAzure study has demonstrated that the use of the bisphosphonate zoledronic acid (Zol in the neoadjuvant setting increases the rate of complete response in primary breast cancer and therefore indicates direct antitumor activity. The purpose of this study was to compare the antitumor effect of Zol with standard chemotherapy in primary breast cancer cells using ATP-tumor chemosensitivity assay (ATP-TCA. Methods Breast cancer specimens were obtained from patients with breast cancer who underwent primary breast cancer surgery at the Department of Obstetrics and Gynecology, Tübingen, Germany, between 2006 through 2009. Antitumor effects of Zol, TAC (Docetaxel, Adriamycin, Cyclophosphamide and FEC (5-Fluorouracil, Epirubicin, Cyclophosphamide were tested in 116 fresh human primary breast cancer specimens using ATP-TCA. ATP-TCA results were analyzed with different cut-off levels for the half maximal inhibitory concentration (IC50, for IC90 and for the sensitivity index (IndexSUM. Each single agent or combination was tested at six doubling dilutions from 6.25, 12.5, 25, 50, 100, and 200% of test drug concentrations (TDC derived from the plasma peak concentrations determined by pharmacokinetic data. The assay was carried out in duplicate wells with positive and negative controls. Results The median IndexSUM value was lower for Zol than for the combined regimen FEC (36.8% and TAC (12.9%, respectively, indicating increased antitumor activity of Zol in primary breast cancer cells. The difference regarding Zol and FEC was significant (p  Conclusion Zoledronic acid has a strong antitumor effect on primary breast cancer cells in vitro which is equal or superior to commonly used chemotherapeutic regimens for treating breast cancer.

  10. Blockage of SSRP1/Ets-1/Pim-3 signalling enhances chemosensitivity of nasopharyngeal carcinoma to docetaxel in vitro.

    Science.gov (United States)

    Ai, Jingang; Li, Wei; Zeng, Ruifang; Xie, Zuozhong; Liu, Honghui; Hou, Minghua; Tan, Guolin

    2016-10-01

    Nasopharyngeal carcinoma (NPC) is a rare cancer in most parts of the world, but is prevalent in South China area. Besides, therapeutic outcome is still unsatisfactory for patients with refractory and relapsed NPC, even though receiving a second line of docetaxel-based chemotherapy. These reasons require a better understanding of mechanisms underlying the carcinogenesis, malignancy and chemoresistance. In the basis of our previous finding of SSRP1 over-expression in NPC cell lines, this study continuously discovered up-regulated Ets-1, phosphor-Ets-1 and Pim-3 in NPC tissues with immunohistochemistry assay and revealed a close correlation of these up-regulated proteins with NPC proliferation and invasion. Using gene-silencing technology followed by western blot and immunocytochemistry detections, SSRP1 was found to facilitate the translocation of phosphor-Ets-1 from cytoplasm to cell nucleus, but have marginal effect on Ets-1 expression and phosphorylation. Pim-3 was positively regulated by Ets-1. In NPC HNE-1 cells, all SSRP1, Ets-1 and Pim-3 knockdown diminished the cell proliferation, enhanced the apoptosis, as well as inhibited the autophagy, invasion and clonogenicity in the presence or absence of docetaxel at IC25. Exposure of HNE-1 cells to docetaxel (IC25) alone had modest effect on cell proliferation and autophagy, and was not as effective as docetaxel treatment after knockdown of SSRP1, Ets-1 or Pim-3 on induction of the apoptosis and on inhibition of the invasion and clonogenicity. Our data indicate that SSRP1/Ets-1/Pim-3 signalling is tightly associated with the proliferation, apoptosis, autophagy, invasion and clonogenicity of NPC cells, and blockage of this signalling facilitates chemosensitivity of the cells to docetaxel.

  11. Targeting the ∆133p53 isoform can restore chemosensitivity in 5-fluorouracil-resistant cholangiocarcinoma cells.

    Science.gov (United States)

    Nutthasirikul, Nichapavee; Hahnvajanawong, Chariya; Techasen, Anchalee; Limpaiboon, Temduang; Leelayuwat, Chanvit; Chau-In, Siri; Jearanaikoon, Patcharee

    2015-12-01

    Lack of the normal p53 transactivation domain, ∆133p53 isoform exhibits anti-p53 function. Many studies report the correlation between ∆133p53 expression and poor survival in various cancers, including cholangiocarcinoma (CCA), which is a cancer of the bile ducts. CCA almost always results in short survival times. The relevance of ∆133p53 to drug resistance in CCA is not yet well understood. This study aimed to demonstrate the association between ∆133p53 and 5-fluorouracil (5-FU) resistance in CCA. ∆133p53 protein was highly expressed in CCA patients with poor outcome compared to favorable outcome but was not statistically significant. However, a significant correlation was found between normalized ∆133p53 levels and 5-FU resistance which was defined by an ex vivo histoculture drug response assay (P=0.019). Two stable 5-FU-resistant CCA cell lines, KKU-M139R (IC50 38.8 µM) and KKU-M214R (IC50 39.5 µM), were used as a model to evaluate the role of ∆133p53. Increased ∆133p53 was correlated with 5-FU in a dose-dependent manner. The transient knockdown of ∆133p53 expression can restore drug sensitivity in both resistant CCA cells with 11- to 45-fold reduction of IC50 compared to control. Upon ∆133p53 silencing, apoptotic signaling was enhanced by the upregulation of Bax and downregulation of Bcl-2. Additionally, p21 and p27 were upregulated, resulting in cell cycle arrest at G2. Inhibition of colony formation and prolong doubling time were also observed. Our findings demonstrated that chemosensitivity can be modulated via targeting of ∆133p53 suggesting the potential use of ∆133p53 as a candidate for targeting therapy in CCA.

  12. A Disintegrin and Metalloproteinase Domain 17 Regulates Colorectal Cancer Stem Cells and Chemosensitivity Via Notch1 Signaling.

    Science.gov (United States)

    Wang, Rui; Ye, Xiangcang; Bhattacharya, Rajat; Boulbes, Delphine R; Fan, Fan; Xia, Ling; Ellis, Lee M

    2016-03-01

    Evidence is accumulating for the role of cancer stem cells (CSCs) in mediating chemoresistance in patients with metastatic colorectal cancer (mCRC). A disintegrin and metalloproteinase domain 17 (ADAM17; also known as tumor necrosis factor-α-converting enzyme [TACE]) was shown to be overexpressed and to mediate cell proliferation and chemoresistance in CRC cells. However, its role in mediating the CSC phenotype in CRC has not been well-characterized. The objective of the present study was to determine whether ADAM17 regulates the CSC phenotype in CRC and to elucidate the downstream signaling mechanism that mediates cancer stemness. We treated established CRC cell lines and a newly established human CRC cell line HCP-1 with ADAM17-specific small interfering RNA (siRNA) or the synthetic peptide inhibitor TAPI-2. The effects of ADAM17 inhibition on the CSC phenotype and chemosensitivity to 5-fluorouracil (5-FU) in CRC cells were examined. siRNA knockdown and TAPI-2 decreased the protein levels of cleaved Notch1 (Notch1 intracellular domain) and HES-1 in CRC cells. A decrease in the CSC phenotype was determined by sphere formation and ALDEFLUOR assays. Moreover, TAPI-2 sensitized CRC cells to 5-FU by decreasing cell viability and the median lethal dose of 5-FU and increasing apoptosis. We also showed the cleavage and release of soluble Jagged-1 and -2 by ADAM17 in CRC cells. Our studies have elucidated a role of ADAM17 in regulating the CSC phenotype and chemoresistance in CRC cells. The use of drugs that inhibit ADAM17 activity might increase the therapeutic benefit to patients with mCRC and, potentially, those with other solid malignancies.

  13. The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis.

    Science.gov (United States)

    Herath, Nirmitha I; Devun, Flavien; Lienafa, Marie-Christine; Herbette, Aurélie; Denys, Alban; Sun, Jian-Sheng; Dutreix, Marie

    2016-01-01

    Metastatic liver disease from colorectal cancer is a significant clinical problem. This is mainly attributed to nonresectable metastases that frequently display low sensitivities to available chemotherapies and develop drug resistance partly via hyperactivation of some DNA repair functions. Combined therapies have shown some disease control; however, there is still a need for more efficient chemotherapies to achieve eradication of colorectal cancer liver metastasis. We investigated the tolerance and efficacy of a novel class of DNA repair inhibitors, Dbait, in association with conventional chemotherapy. Dbait mimics double-strand breaks and activates damage signaling, consequently inhibiting single- and double-stranded DNA repair enzyme recruitment. In vitro, Dbait treatment increases sensitivity of HT29 and HCT116 colorectal cancer cell lines. In vivo, the pharmacokinetics, biodistribution and the efficacy of the cholesterol-conjugated clinical form of Dbait, DT01, were assessed. The chemosensitizing abilities of DT01 were evaluated in association with oxaliplatin and 5-fluorouracil in intrahepatic HT29 xenografted mice used as a model for colorectal cancer liver metastasis. The high uptake of DT01 indicates that the liver is a specific target. We demonstrate significant antitumor efficacy in a liver metastasis model with DT01 treatment in combination with oxaliplatin and 5-fluorouracil (mean: 501 vs. 872 mm(2), P = 0.02) compared to chemotherapy alone. The decrease in tumor volume is further associated with significant histologic changes in necrosis, proliferation, angiogenesis and apoptosis. Repeated cycles of DT01 do not increase chemotherapy toxicity. Combining DT01 with conventional chemotherapy may prove to be a safe and effective therapeutic strategy in the treatment of metastatic liver cancer.

  14. Expression of TP53 isoforms p53β or p53γ enhances chemosensitivity in TP53(null cell lines.

    Directory of Open Access Journals (Sweden)

    Elisabeth Silden

    Full Text Available The carboxy-terminal truncated p53 alternative spliced isoforms, p53β and p53γ, are expressed at disparate levels in cancer and are suggested to influence treatment response and therapy outcome. However, their functional role in cancer remains to be elucidated. We investigated their individual functionality in the p53(null background of cell lines H1299 and SAOS-2 by stable retroviral transduction or transient transfection. Expression status of p53β and p53γ protein was found to correlate with increased response to camptothecin and doxorubicin chemotherapy. Decreased DNA synthesis and clonogenicity in p53β and p53γ congenic H1299 was accompanied by increased p21((CIP1/WAF1, Bax and Mdm2 proteins. Chemotherapy induced p53 isoform degradation, most prominent for p53γ. The proteasome inhibitor bortezomib substantially increased basal p53γ protein level, while the level of p53β protein was unaffected. Treatment with dicoumarol, a putative blocker of the proteasome-related NAD(PH quinone oxidoreductase NQO1, effectively attenuated basal p53γ protein level in spite of bortezomib treatment. Although in vitro proliferation and clonogenicity assays indicated a weak suppressive effect by p53β and p53γ expression, studies of in vivo subcutaneous H1299 tumor growth demonstrated a significantly increased growth by expression of either p53 isoforms. This study suggests that p53β and p53γ share functionality in chemosensitizing and tumor growth enhancement but comprise distinct regulation at the protein level.

  15. miR-218 suppresses tumor growth and enhances the chemosensitivity of esophageal squamous cell carcinoma to cisplatin.

    Science.gov (United States)

    Tian, Hang; Hou, Lei; Xiong, Yu-Mei; Huang, Jun-Xiang; She, Ying-Jun; Bi, Xiao-Bao; Song, Xing-Rong

    2015-02-01

    A growing body of evidence suggests that microRNA-218 (miR-218) acts as a tumor suppressor and is involved in tumor progression, development and metastasis and confers sensitivity to certain chemotherapeutic drugs in several types of cancer. However, our knowledge concerning the exact roles played by miR-218 in esophageal squamous cell carcinoma (ESCC) and the underlying molecular mechanisms remain relatively unclear. Thus, the aims of this study were to detect the expression of miR-218 in human ESCC tissues and explore its effects on the biological features and chemosensitivity to cisplatin (CDDP) in an ESCC cell line (Eca109), so as to provide new insights for ESCC treatment. Here, we found increased expression of miR-218 in the ESCC tissues compared with that in the matched non-tumor tissues, and its expression level was correlated with key pathological characteristics including clinical stage, tumor depth and metastasis. We also found that enforced expression of miR-218 significantly decreased cell proliferation, colony formation, migration and invasion, induced cell apoptosis and arrested the cell cycle in the G0/G1 phase, as well as suppressed tumor growth in a nude mouse model. In addition, our results showed that miR-218 mimics increased the sensitivity to the antitumor effect of CDDP in the human Eca109 cells. Importantly, this study also showed that miR-218 regulated the expression of phosphorylated PI3K, AKT and mTOR, which may contribute to suppressed tumor growth of ESCC and enhanced sensitivity of ESCC cells. These findings suggest that miR-218 is a potential therapeutic agent for the treatment of ESCC.

  16. Differential processing of let-7a precursors influences RRM2 expression and chemosensitivity in pancreatic cancer: role of LIN-28 and SET oncoprotein.

    Directory of Open Access Journals (Sweden)

    Yangzom Doma Bhutia

    Full Text Available Overexpression of ribonucleotide reductase subunit M2 (RRM2, involved in deoxyribonucleotide synthesis, drives the chemoresistance of pancreatic cancer to nucleoside analogs (e.g., gemcitabine. While silencing RRM2 by synthetic means has shown promise in reducing chemoresistance, targeting endogenous molecules, especially microRNAs (miRNAs, to advance chemotherapeutic outcomes has been poorly explored. Based on computational predictions, we hypothesized that the let-7 tumor suppressor miRNAs will inhibit RRM2-mediated gemcitabine chemoresistance in pancreatic cancer. Reduced expression of the majority of let-7 miRNAs with an inverse relationship to RRM2 expression was identified in innately gemcitabine-resistant pancreatic cancer cell lines. Direct binding of let-7 miRNAs to the 3' UTR of RRM2 transcripts identified post-transcriptional regulation of RRM2 influencing gemcitabine chemosensitivity. Intriguingly, overexpression of human precursor-let-7 miRNAs led to differential RRM2 expression and chemosensitivity responses in a poorly differentiated pancreatic cancer cell line, MIA PaCa-2. Defective processing of let-7a precursors to mature forms, in part, explained the discrepancies observed with let-7a expressional outcomes. Consistently, the ratios of mature to precursor let-7a were progressively reduced in gemcitabine-sensitive L3.6pl and Capan-1 cell lines induced to acquire gemcitabine resistance. Besides known regulators of let-7 biogenesis (e.g., LIN-28, short hairpin RNA library screening identified several novel RNA binding proteins, including the SET oncoprotein, to differentially impact let-7 biogenesis and chemosensitivity in gemcitabine-sensitive versus -resistant pancreatic cancer cells. Further, LIN-28 and SET knockdown in the cells led to profound reductions in cellular proliferation and colony-formation capacities. Finally, defective processing of let-7a precursors with a positive correlation to RRM2 overexpression was

  17. Chemo-sensitization of fungal pathogens to antimicrobial agents using benzaldehyde analogs

    Science.gov (United States)

    Activity of conventional antifungal agents, fludioxonil, strobilurin and antimycinA, which target the oxidative and osmotic stress response systems, was elevated by co-application of certain analogs of benzaldehyde. Fungal tolerance to 2,3-dihydroxybenzaldehyde or 2,3-dihydroxybenzoic acid was foun...

  18. Down-Regulating Cold Shock Protein Genes Impairs Cancer Cell Survival and Enhances Chemosensitivity

    OpenAIRE

    2009-01-01

    The microenvironment of the cancer cell is pivotal to its phenotypic regulation. One of the central components of the microenvironment is temperature. An elevation in environmental temperature has been shown to increase the cancer cell's susceptibility to chemo- and radiation therapy. The goal of the studies described here was to identify some of the pathways that are modified by a mild increase in temperature in cancer cells. Using prostate cancer cells as a model system we found that in add...

  19. [In vitro evaluation of the chemosensitivity of malignant gastrointestinal tumors by stem cell assay].

    Science.gov (United States)

    Scheithauer, W; Temsch, E M; Schieder, H; Funovics, J; Schiessel, R; Grabner, G

    1984-01-01

    The Human Tumor Stem Cell Assay, originally described by Hamburger and Salmon, was shown to be a useful in-vitro technique for predicting response or lack of response in individual patients' tumors. In the present study 34 GI-tumors were assayed for evaluation of in-vitro growth characteristics and sensitivity-patterns to standard chemotherapeutic drugs as well as to recombinant interferon alpha-2(rIF). Sufficient growth for evaluation of anticancer drug activity (greater than 30 colonies/control plate) was obtained in 56% of specimens: 2/9 colorectal, 0/3 stomach, 0/3 pancreatic tumors and 1/4 hepatomas revealed a 50% (or more) decrease of TCFUs, that was considered the minimum for in-vitro efficacy. Our results suggest a very limited overall activity of rIF in gastrointestinal malignancies. Only 1 pancreatic cancer (of 18 evaluable specimens) showed a significant decrease of colony formation (70%), when 100 U of interferon/ml were added to the culture system.

  20. Effects of multidrug resistance, antisense RNA on the chemosensitivity of hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Bo Li; Jian-Ping Gong; Tian Ye; Lei Zhao; De-Hua Li; Xing-Hua Gou; Lan-Ying Zhao; Lei Han; Lin Chen; Lu-Nan Yan

    2006-01-01

    BACKGROUND: Multidrug resistance is a major obstacle in cancer chemotherapy. We examined whether the antisense RNA of multidrug resistance gene 1 (mdr1) could reverse multidrug resistance in the human hepatocellular carcinoma (HCC) cell line SMMC7721/ADM. METHODS: The recombinant adenoviruses pAdEasy-GFP-ASmdr1 product was produced by the adenoviral vector AdEasy system, which can express antisense RNA against the mdr1 gene. Following that, the recombinant adenovirus was transfected into the P-glycoprotein-producing multidrug resistance cell line, SMMC7721/ADM human HCC cells resistant to adriamycin (ADM) and daunorubicin (DNR). In order to investigate the reversal of multidrug resistance phenotype, we measured the expression of mdr1 mRNA by RT-PCR and the production of P-glycoprotein by lfow cytometry. The sensitivities for ADM and DNR SMMC7721/ADM cells were examined by [3-(4, 5-dimethylthi-azol-2-yl)-2,5 diphenyl-terazolium bromide] (MTT) analysis. RESULTS: The low-level expression of mdr1 mRNA and P-glycoprotein production were observed in parental sensitive cells SMMC/7721 in addition to the overexpression of mdr1 mRNA and P-glycoprotein in SMMC7721/ADM cells. The transfection of antisense-RNA into SMMC7721/ADM cells resulted in decreases of mdr1 mRNA and P-glycoprotein, but increase of drug sensitivities. The sensitivities of transfected SMMC7721/ADM cells to ADM and DNR in IC50 reduced by 31.25% and 62.96%respectively. CONCLUSIONS: Mdr1 antisense RNA can increase the sensitivities of SMMC7721/ADM cells to anticancer drug by decreasing the expression of the mdr1 gene and inhibiting P-glycoprotein expression. This strategy may be applicable to cancer patients with P-glycoportein mediated multidrug resistance.

  1. Effects of glucocorticoids on the growth and chemosensitivity of carcinoma cells are heterogeneous and require high concentration of functional glucocorticoid receptors

    Institute of Scientific and Technical Information of China (English)

    Yen-Shen Lu; Huang-Chun Lien; Pei-Yen Yeh; Kun-Huei Yeh; Min-Liang Kuo; Sung-Hsin Kuo; Ann-Lii Cheng

    2005-01-01

    AIM: To determine how glucocorticoids (GCs) may affect the growth and chemosensitivity of common carcinoma cells.METHODS: The effect of dexamethasone (DEX) on growth and chemosensitivity was assessed in 14 carcinoma cell lines. The function of GC receptors (GR) was assessed by MMTV reporter assay. Overexpression of GR was done by in vitro transfection and expression of a GR-expressing vector. Immunohistochemical stain of tissues and cells were done by PA1-511A, an anti-GR monoclonal antibody.RESULTS: DEX inhibited cell growth of four (MCF-7, MCF-7/MXR1, MCF-7/TPT300, and HeLa), increased cisplatin cytotoxicity of one (SiHa), and decreased cisplatin cytotoxicity of two (H460 and Hep3B) cell lines. The GR content of the seven cell lines affected by DEX was significantly higher than those of the seven cell lines unaffected by DEX(5.2±2.5×104 sites/cell vs 1.3±1.4×104 sites/cell, P= 0.005).Only two DEX-unresponsive cell lines (NPC-TW01 and NPCTW04) contained high GR amounts in the range (1.9-8.1×104sites/cell) of the seven DEX-responsive cell lines. The GR function of NPC-TW01 and NPC-TW04, however, was found to be impaired. The importance of high cellular amount of GR in mediating DEX susceptibility of the cells was further exemplified by GR dose-dependent drug resistance to cisplatin of AGS, a cell line with low GR content and was unaffected by DEX before transfection of GR-expressing vector. Immunohistochemical studies of human cancer tissues showed that 5 of the 45 (11.1%) breast cancer and 43 of the 85 (50.6%) non-small cell lung cancer had high GR contents at the ranges of the GC-responsive carcinoma cell lines.CONCLUSION: The growth and chemosensitivity of human carcinomas with high GR contents may be affected by GC. However, in light of the heterogeneous and even contradictive effects of GC on these cells, routine examination of GR contents of human carcinoma tissues may not be clinically useful until other markers that help predict the ultimate effect of

  2. Use of an ATP-based chemosensitivity assay to design new combinations of high-concentration doxorubicin with other drugs for recurrent ovarian cancer.

    Science.gov (United States)

    Di Nicolantonio, Federica; Neale, Michael H; Knight, Louise A; Lamont, Alan; Skailes, Geraldine E; Osborne, Richard J; Allerton, Rosanne; Kurbacher, Christian M; Cree, Ian A

    2002-07-01

    Liposomal doxorubicin (Caelyx/Doxil) has been shown to be active in around 20% of recurrent ovarian cancers. As yet, there is little clinical data on combinations of existing agents with liposomal doxorubicin, despite considerable clinical experience with soluble doxorubicin in combination. In this study, we have used an ATP-based tumor chemosensitivity assay to determine the relative efficacy of high concentrations of doxorubicin tested in combination with cisplatin, treosulfan, 5-fluorouracil (5-FU) or vinorelbine against cells obtained from recurrent ovarian tumor tissue. The results show little enhancement of the efficacy of high concentrations of doxorubicin by 5-FU, cisplatin, or treosulfan. However, vinorelbine+liposomal doxorubicin showed additive inhibition, and this combination is worthy of further testing in clinical trials.

  3. Antitumor and chemosensitizing action of dichloroacetate implicates modulation of tumor microenvironment: A role of reorganized glucose metabolism, cell survival regulation and macrophage differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra, E-mail: sukhmahendrasingh@yahoo.com

    2013-11-15

    Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, which is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment.

  4. Antitumor agents 286. Design, synthesis, and structure-activity relationships of 3'R,4'R-disubstituted-2',2'-dimethyldihydropyrano[2,3-f]chromone (DSP) analogues as potent chemosensitizers to overcome multidrug resistance.

    Science.gov (United States)

    Zhou, Ting; Shi, Qian; Bastow, Kenneth F; Lee, Kuo-Hsiung

    2010-12-23

    In this study, various 3'R,4'R-disubstituted-2',2'-dimethydihydropyrano[2,3-f]chromone (DSP) derivatives were discovered as potent chemosensitizers in the treatment of multidrug resistant cancer cells. Twenty-four DSP analogues (5-28) were synthesized and evaluated against a multidrug resistant (MDR) cell line (KB-Vin) with and without vincristine (VCR). All DSP analogues exhibited low intrinsic cytotoxicity. However, in combination treatment, most DSPs reversed resistance to VCR and lowered the GI₅₀ value of VCR by 12-349-fold. At a concentration of 1 μg/mL, three compounds, 11, 14, and 21, fully reversed resistance to VCR in KB-Vin cancer cells, a 2-fold increase compared to verapamil, a first-generation chemosensitizer. Detailed structure-activity relationship (SAR) conclusions were established based on 3' and 4' substitutions. Moreover, a preliminary mechanism study indicated that the chemosensitizing activity of DSP analogues results from inhibition of P-glycoprotein (P-gp) overexpressed in MDR cancer cells.

  5. Prognostic value of the age-adjusted International Prognostic Index in chemosensitive recurrent or refractory non-Hodgkin's lymphomas treated with high-dose BEAM therapy and autologous stem cell transplantation.

    Science.gov (United States)

    Jabbour, E; Peslin, N; Arnaud, P; Ferme, C; Carde, P; Vantelon, J M; Bocaccio, C; Bourhis, J H; Koscielny, S; Ribrag, V

    2005-06-01

    High-dose therapy (HDT) is now recommended for patients under 60 years of age with chemosensitive relapsed aggressive non-Hodgkin's lymphoma. However, approximately half of these patients will be cured by HDT. Prognostic factors are needed to predict which patients with chemosensitive lymphoma to second-line therapy could benefit from HDT. We retrospectively investigated the prognostic value of the widely used age-adjusted International Prognostic Index (AA-IPI) calculated at the time of relapse (35 patients) or just before second-line salvage therapy for primary refractory disease (5 patients). The median age was 51 years (range 18-64 years). Thirty-six patients had diffuse large B-cell lymphoma. Salvage cytoreductive therapy before HDT was DHAP/ESHAP (cytarabine, cysplatin, etoposide, steroids) in 17 patients, VIM3-Ara-c/MAMI (high-dose cytarabine, ifosfamide, methyl-gag, amsacrine) in 17 patients, CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or reinforced CHOP in 4 patients, high-dose cyclophosphamide and etoposide in 2 patients. The HDT regimen consisted of BEAM (carmusine, cytarabine, etoposide, melphalan) in all cases. Eleven patients were in partial remission and 29 in complete remission at the time of HDT. Ten patients had an IPI >1, 16 had relapsed early (6 months after first-line chemotherapy) (P=1), but the AA-IPI >1 was associated with a poor outcome (P=0.03). In conclusion, the AA-IPI could have a prognostic value in patients with chemosensitive recurrent lymphoma treated with BEAM HDT.

  6. Application value of ATP based bioluminescence tumor chemosensitivity assay in the chemotherapy for hydrothorax caused by non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Kaijian Le; Yuming Jia; Jing Wang; Maoqiong Jiang

    2013-01-01

    Objective: The aim of the study was to investigate the clinical value and application of ATP based bioluminescencetumor chemosensitivity assay (ATP-TCA) in the chemotherapy for hydrothorax caused by non-small cell lung cancer(NSCLC). Methods: Hydrothorax specimens from 120 NSCLC patients were analyzed by ATP-TCA and the most sensitivechemotherapeutic drugs were used in NSCLC patients (treatment group). At the same time, 56 NSCLC patients with hydrothoraxwere admitted in our Hospital (Department of Oncology, The No. 2 People's Hospital of Yibin, China) and given chemotherapywithout guidance of the ATP-TCA (control group). Before the third chemotherapeutic cycle, clinical outcomes wereanalyzed in the two groups. Results: Effective rate of hydrothorax in treatment group was 67%, while 46% in control group(P < 0.05). In refractory hydrothorax patients, they were 69% and 40% (P < 0.05), respectively. In vitro results correlated wellwith clinical outcomes (P < 0.01). Conclusion: Effective rate of chemotherapy for hydrothorax in NSCLC is higher in treatmentgroup than that in control group. ATP-TCA is especially helpful for refractory hydrothorax.

  7. Antrodia cinnamomea alleviates cisplatin-induced hepatotoxicity and enhances chemo-sensitivity of line-1 lung carcinoma xenografted in BALB/cByJ mice.

    Science.gov (United States)

    Huang, Tse-Hung; Chiu, Yi-Han; Chan, Yi-Lin; Wang, Hang; Li, Tsung-Lin; Liu, Chien-Yin; Yang, Cheng-Ta; Lee, Tzung-Yan; You, Jyh-Sheng; Hsu, Kuang-Hung; Wu, Chang-Jer

    2015-09-22

    Whereas cisplatin (cis-diamminedichloroplatinum II) is a first-line medicine to treat solid cancerous tumors, it often causes serious side effects. New medicines that have an equivalent or even better therapeutic effect but with free or less side effects than cisplatin are highly anticipated in cancer therapy. Recent reports revealed that Antrodia cinnamomea (AC) possesses hepatoprotective activity in addition to anticancer. In this study, we wanted to know whether AC enhances chemo-sensitivity of cisplatin and/or alleviates cisplatin-induced hepatotoxicity, as well as the underlying mechanisms thereof. Our results indicated that AC inhibited proliferation of line-1 lung carcinoma cells and rescued hepatic HepG2 cells from cisplatin-induced cell death in vitro. The fact is that AC and cisplatin synergized to constrain growth of line-1 lung carcinoma cells in BALB/cByJ mice. Quantitative real-time PCR further revealed that AC promoted expression of apoptosis-related genes, while it decreased expression of NF-κB and VEGF in tumor tissues. In liver, AC reduced cisplatin-induced liver dysfunctions, liver inflammation and hepatic apoptosis in addition to body weight restoration. In summary, AC is able to increase cisplatin efficacy by triggering expression of apoptosis-related genes in line-1 lung cancer cells as well as to protect liver from tissue damage by avoiding cisplatin-induced hepatic inflammation and cell death.

  8. Copper oxide and zinc oxide nanomaterials act as inhibitors of multidrug resistance transport in sea urchin embryos: their role as chemosensitizers.

    Science.gov (United States)

    Wu, Bing; Torres-Duarte, Cristina; Cole, Bryan J; Cherr, Gary N

    2015-05-05

    The ability of engineered nanomaterials (NMs) to act as inhibitors of ATP-binding cassette (ABC) efflux transporters in embryos of white sea urchin (Lytechinus pictus) was studied. Nanocopper oxide (nano-CuO), nanozinc oxide (nano-ZnO), and their corresponding metal ions (CuSO4 and ZnSO4) were used as target chemicals. The results showed that nano-CuO, nano-ZnO, CuSO4, and ZnSO4, even at relatively low concentrations (0.5 ppm), significantly increased calcein-AM (CAM, an indicator of ABC transporter activity) accumulation in sea urchin embryos at different stages of development. Exposure to nano-CuO, a very low solubility NM, at increasing times after fertilization (>30 min) decreased CAM accumulation, but nano-ZnO (much more soluble NM) did not, indicating that metal ions could cross the hardened fertilization envelope, but not undissolved metal oxide NMs. Moreover, nontoxic levels (0.5 ppm) of nano-CuO and nano-ZnO significantly increased developmental toxicity of vinblastine (an established ABC transporter substrate) and functioned as chemosensitizers. The multidrug resistance associated protein (MRP, one of ABC transporters) inhibitor MK571 significantly increased copper concentrations in embryos, indicating ABC transporters are important in maintaining low intracellular copper levels. We show that low concentrations of nano-CuO and nano-ZnO can make embryos more susceptible to other contaminants, representing a potent amplification of nanomaterial-related developmental toxicity.

  9. Inhibition of CD147 expression by RNA interference reduces proliferation, invasion and increases chemosensitivity in cancer stem cell-like HT-29 cells.

    Science.gov (United States)

    Chen, Jie; Pan, Yuqin; He, Bangshun; Ying, Houqun; Wang, Feng; Sun, Huiling; Deng, Qiwen; Liu, Xian; Lin, Kang; Peng, Hongxin; Cho, William C; Wang, Shukui

    2015-10-01

    The association between CD147 and cancer stem cells (CSCs) provides a new angle for cancer treatments. The aim of this study was to investigate the biological roles of CD147 in colorectal CSCs. The Oct4-green fluorescent protein (GFP) vector was used to isolate CSCs and pYr-mir30-shRNA was used to generate short hairpin RNA (shRNA) specifically for CD147. After RNA interference (RNAi), CD147 was evaluated by reverse transcription‑quantitative PCR and western blot analysis, and its biological functions were assessed by MTT and invasion assays. The results showed that the differentiation of isolated CSC-like HT-29 cells was blocked and these cells were highly positive for CD44 and CD147. RNAi-mediated CD147 silencing reduced the expression of CD147 at both mRNA and protein levels. Moreover, the activities of proliferation and invasion were decreased obviously in CSCs. Knockdown of CD147 increased the chemosensitivity of CSC-like cells to gemcitabine, cisplatin, docetaxel at 0.1, 1 and 10 µM respectively, however, there was no significant difference among the three groups to paclitaxel at 10 µM. In conclusion, these results suggest that CD147 plays an important role in colorectal CSCs and might be regarded as a novel CSC-specific targeted strategy against colorectal cancer.

  10. In Vitro Chemosensitivity of Fluorouracil and Oxaliplatin in Gastric Cancer%氟尿嘧啶和奥沙利铂在胃癌中的体外化疗敏感性检测

    Institute of Scientific and Technical Information of China (English)

    陈小东; 赵平; 丁志; 周祥; 肖硕萌; 唐令超

    2014-01-01

    目的:探讨氟尿嘧啶(5-FU)和奥沙利铂(OX)在胃癌中的体外化疗敏感性。方法:纳入病理确诊并自愿接受检测的胃癌患者,采用ATP肿瘤化疗敏感性检测法( ATP-TCA)检测新鲜手术标本对5-FU和OX的体外化疗敏感性。结果:纳入27例,男性21例、女性6例,中位年龄60.0岁,远侧部胃癌14例(51.9%),低分化及印戒细胞癌共20例(74.1%),TNM Ⅲ+Ⅳ期21例(77.8%)。 ATP-TCA检测显示5-FU+OX在各药物浓度的肿瘤生长抑制率均显著高于5-FU或OX(P<0.05),5-FU+OX的抑制曲线下面积显著高于5-FU或OX(P<0.05);而其化疗敏感指数、IC90和IC50显著低于5-FU或OX ( P<0.05)。5-FU、OX和5-FU+OX的体外化疗敏感性依次为18.5%、14.8%和55.6%,5-FU+OX的敏感性显著高于5-FU或OX(5-FU+OX vs.5-FU:P=0.001和5-FU+OX vs. OX:P=0.003)。 Logistic回归分析显示5-FU的敏感性与临床病理特征无显著相关性,而OX和5-FU+OX的敏感性分别与Borrmann分型(OR=7.570,P=0.025)和肿瘤位置(OR=3.427,P=0.019)有显著相关性。结论:5-FU+OX在胃癌中显示出较高的体外化疗敏感性,但其与体内疗效的相关性有待进一步临床观察。%Objective: To investigate the in vitro chemosensitivity of fluorouracil (5-FU) and oxaliplatin (OX) in gastric cancer. Methods:Patients with histologically confirmed gastric cancer were enrolled for the study. All patients a-greed to the chemosensitivity test of their resected tumors and gave informed consent. Adenosine triphosphate tumor chemo-sensitivity assay ( ATP-TCA) was performed to determine the chemosensitivity of 5-FU and OX in resected gastric cancer specimens. Results:Twenty-seven patients with a median age of 60. 0 were enrolled, including 21 males and 6 females. The tumors were located in the lower part of the stomach in 14 cases, 20 cases were poorly differentiated or signet-ring cell carcinoma and 21 cases were in late TNM stage. ATP-TCA assay showed that the

  11. Lack of nucleophilic addition in the isoxazole and pyrazole diketone modified analogs of curcumin; implications for their antitumor and chemosensitizing activities.

    Science.gov (United States)

    Labbozzetta, Manuela; Baruchello, Riccardo; Marchetti, Paolo; Gueli, Maria C; Poma, Paola; Notarbartolo, Monica; Simoni, Daniele; D'Alessandro, Natale

    2009-09-14

    Curcumin (CUR) can be considered as a good lead compound for the design of new anticancer drugs. Further, structure-activity relationship studies may clarify the importance of the redox activities in the antitumor effects of the drug. We have elaborated the alpha,beta-unsaturated 1,3-diketone moiety of CUR into the isoxazole (ISO) and pyrazole (PYR) derivatives. These derivatives should be much less prone to nucleophilic addition than CUR and benzyl mercaptan addition analyses showed that indeed they do not form isolable conjugated products. When compared with CUR, ISO and PYR exhibited increased cell growth inhibitory and pro-apoptotic effects in liver cancer HA22T/VGH cells as well as in other tumor cell types; in contrast to CUR, the antitumor effects of ISO or PYR were not influenced by concomitant administration of N-acetylcysteine, as a source of -SH groups, or buthionine sulfoximine, as an inhibitor of glutathione synthesis. Further, treatment with CUR, but not with ISO or PYR, significantly decreased the content of reduced glutathione in the HA22T/VGH cells. Finally, ISO and PYR lacked the ability of the parent compound to sensitize the HA22T/VGH cells to cisplatin (CIS), an effect which appeared to occur through an interaction of CUR and CIS at the level of the -SH groups. Thus, the ability of interacting with cell thiols might not be requested for the more potent antitumor activities of new diketone modified CUR derivatives, which might rely on other mechanisms, though possibly devoid of chemosensitization capabilities.

  12. The effect of adenovirus expressing wild-type p53 on 5-fiuorouracil chemosensitivity is related to p53 status in pancreatic cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Sven Eisold; Michael Linnebacher; Eduard Ryschich; Dalibor Antolovic; Ulf Hinz; Ernst Klar; Jan Schmidt

    2004-01-01

    AIM: There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU).Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status.METHODS: Human pancreatic cancer cell lines Capan-1p53mut,Capan-2p53wt, FAMPACp53mut, PANC1p53mut, and rat pancreatic cancer cell lines ASp53wt and DSL6Ap53null were used for in vitro studies. Following infection with different ratios of Adp53-particles (MOI) in combination with 5-FU, proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining). In addition, DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivo studies.Tumor size, apoptosis (TUNEL) and survival were determined.RESULTS: Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53. In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU. Both in vitro and in vivo analyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU.CONCLUSION: Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function. These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.

  13. Sleep study, respiratory mechanics, chemosensitive response and quality of life in morbidly obese patients undergoing bariatric surgery: a prospective, randomized, controlled trial

    Directory of Open Access Journals (Sweden)

    Leitao Filho Fernando SS

    2011-10-01

    Full Text Available Abstract Background Obesity is a major public health problem in both developed and developing countries alike and leads to a series of changes in respiratory physiology. There is a strong correlation between obesity and cardiopulmonary sleep disorders. Weight loss among such patients leads to a reduction in these alterations in respiratory physiology, but clinical treatment is not effective for a long period of time. Thus, bariatric surgery is a viable option. Methods/Design The present study involves patients with morbid obesity (BMI of 40 kg/m2 or 35 kg/m2 to 39.9 kg/m2 with comorbidities, candidates for bariatric surgery, screened at the Santa Casa de Misericórdia Hospital in the city of Sao Paulo (Brazil. The inclusion criteria are grade III morbid obesity, an indication for bariatric surgery, agreement to participate in the study and a signed term of informed consent. The exclusion criteria are BMI above 55 kg/m2, clinically significant or unstable mental health concerns, an unrealistic postoperative target weight and/or unrealistic expectations of surgical treatment. Bariatric surgery candidates who meet the inclusion criteria will be referred to Santa Casa de Misericórdia Hospital and will be reviewed again 30, 90 and 360 days following surgery. Data collection will involve patient records, personal data collection, objective assessment of HR, BP, neck circumference, chest and abdomen, collection and analysis of clinical preoperative findings, polysomnography, pulmonary function test and a questionnaire on sleepiness. Discussion This paper describes a randomised controlled trial of morbidly obese patients. Polysomnography, respiratory mechanics, chemosensitive response and quality of life will be assessed in patients undergoing or not undergoing bariatric surgery. Trial Registration The protocol for this study is registered with the Brazilian Registry of Clinical Trials - ReBEC (RBR-9k9hhv.

  14. EFFICACY OF IFOSFAMIDE AND VP-16 (ETOPOSIDE) IN PATIENTS WITH SMALL CELL LUNG CANCER AND THE CORRELATION BETWEEN MICROVESSEL COUNT ON CHEMOSENSITIVITY

    Institute of Scientific and Technical Information of China (English)

    WANG Si-wen; LIU Hong-xu; LI Yu

    2006-01-01

    Objective: To evaluate the efficacy of ifosfamide and etoposide (VP-16) in patients with small cell lung cancer (SCLC),and investigate the correlation between microvessel count (MVC) in tumor and chemotherapeutic sensitivity. Methods:Forty-one consecutive cases of SCLC received chemotherapy of ifosfamide plus VP-16 and underwent investigation retrospectively. Immunohistochemistry using anti-human blood type H monoclonal antibody was conducted and MVC was recorded under light microscope. Results: There were 27 limited-disease and 14 extensive-disease patients. The overall response rate was 92.7% (38/41) with 28 cases (68.3%) of complete response (CR), 10 (24.4%) with partial response (PR), 3(7.3%) with progressive disease (PD). The 1-, 2-, 3-, and 5-year survival rates were 68.3% (28/41), 48.3% (20/41), 23.7%(9/38) and 11.1% (3/27), respectively, with the median survival of 26.8 months. The principal toxicities were grade 3-4neutropenia in 8 cases (19.5%), grade 3-4 thrombocytopenia in 6 cases (14.6%), mild liver toxicity in 7 cases (17.0%) and mild renal function damage in 4 cases (9.8%). The mesenchymal vasculature was clearly visualized, with the mean value of 34.7 under each high microscopic power field. Of SCLC with more MVC (n=26), CR accounted for 84.6%; while in cancers with less MVC (n=15), CR took up 40.0%, with significant difference (P<0.05). Conclusion: Administrating ifosfamide and VP-16 is in accordance with the biological features of SCLC and results in beneficial results as well as acceptable side effects.The MVC is positively correlated with the chemotherapeutic sensitivity, and serves as a vital factor contributing to chemosensitivity.

  15. 流式细胞术应用于抗肿瘤药物敏感性实验的可行性研究%The feasibility of antitumor drugs chemosensitivity testing by flow Cytometry

    Institute of Scientific and Technical Information of China (English)

    Jing Yao; Jianhong Wu; Daxing Xie; Xiaolan Li; Deding Tao; Junbo Hu; Jianping Gong

    2007-01-01

    Objective:To investigate the feasibility of chemosensitivity testing of antitumor drugs by flow cytometry in clinical applications so as to provide experimental and theoretical basis for the establishment of a novel antitumor drugs sensitivity testing and the screening of particular antitumor drugs.Methods:Detect the apoptosis rate of 12 cases of Molt-4 cell line.57 cases of fresh clinical gastrointestinal tumor cells by Sub-G1 and Annexin V assay of flow cytometry under the effects of antitumor drugs at different times and the outcomes were compared with the ones of the MTT(3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide)assay.Results:The lethality of drugs on Molt-4 cell clinica gastrointestinal tumor cells had a positive correlation with the acting time of antidrugs by employing Annexin V.Sub-G1 and MTT assay.Drug-incurring maximum lethality of Annexin V assay was higher than MTT colorimetric assay.that of Sub-G1 was lower than MTT assay.the virtual times of Annexin V and Sub-G1 assay were obviously earlier than that of MTT colorimetric assay.Conclusion:Annexin V and Sub-G1 assay of flow cytometry can be taken as potent protocols testing anti-tumor drug chemosensitivity.Annexin V assay is featured by more sensitive,concise,reliable compared with the classical chemosensilivity testing assay Of MTT colorimetric assay and it possesses clinical applied value.

  16. Resveratrol chemosensitizes HER-2-overexpressing breast cancer cells to docetaxel chemoresistance by inhibiting docetaxel-mediated activation of HER-2-Akt axis.

    Science.gov (United States)

    Vinod, B S; Nair, H H; Vijayakurup, V; Shabna, A; Shah, S; Krishna, A; Pillai, K S; Thankachan, S; Anto, R J

    2015-01-01

    As breast cancer cells often develop chemoresistance, better therapeutic options are in search to circumvent it. Here we demonstrate that human epidermal growth factor receptor-2 (HER-2)-overexpressing breast cancer cells resist docetaxel-induced cytotoxicity by upregulating HER-2 and its activity downstream, through Akt and mitogen-activated protein kinase (MAPK) pathways. We observed that introducing resveratrol as a chemosensitizer in docetaxel chemotherapy blocks upregulation and activation of HER-2 in addition to blocking downstream signaling pathways such as Akt. Resveratrol and docetaxel combination results in the synergistic induction of cell death in HER-2-overexpressing SK-BR-3 cells, whereas introduction of wild-type HER-2 in MDA-MD-231 cells increased the resistance to docetaxel. Dominant-negative HER-2 sensitizes SK-BR-3 cells to docetaxel. Our study identified a new synergistic therapeutic combination that targets HER-2-induced breast cancer resistance and might help to overcome therapeutic resistance during breast cancer therapy. The synergism of docetaxel and resveratrol was maximum in SK-BR-3, which is unique among the cell lines studied, due to its high expression status of HER-2, a receptor known to dictate the signaling environment of breast cancer cells. Docetaxel could further induce HER-2 activity in these cells, which was downregulated on resveratrol treatment. Transfection of DN-HER-2 in SK-BR-3 cells inhibits the synergism as the transfection itself sensitizes these cells to docetaxel, leaving no role for resveratrol, whereas ectopic expression of HER-2 introduces the synergism in MDA-MB-231, the triple-negative cell line, in which the synergism was minimum, attesting the crucial role of HER-2 in suppressing the sensitivity to docetaxel. Single-agent docetaxel induced HER-2-mediated resistance to cell death, which was blocked by resveratrol. Resveratrol also downregulated docetaxel-induced activation of MAPK and Akt, survival signaling

  17. miR-590-5p regulates gastric cancer cell growth and chemosensitivity through RECK and the AKT/ERK pathway

    Science.gov (United States)

    Shen, Bo; Yu, Shaorong; Zhang, Yan; Yuan, Yuan; Li, Xiaoyou; Zhong, Jian; Feng, Jifeng

    2016-01-01

    Background The aim of this study was to determine the role of miRNA-590-5p in gastric cancer (GC) progression. Methods Quantitative real-time polymerase chain reaction was performed to measure endogenous miR-590-5p levels in GC cells and tissues. Overexpression or knockdown of miR-590-5p in GC cells was performed by transfection with mimics or an inhibitor, respectively. MTT, matrigel transwell, and Western blot assays were used to assess the effects of miR-590-5p on cell proliferation, invasion, chemosensitivity of GC cells, and the AKT pathway, respectively. In silico prediction and luciferase reporter activity were used to identify potential targets of miR-590-5p. A xenograft model was also established to evaluate the function of miR-590-5p in vivo. Results The expression of miR-590-5p was significantly increased in GC cells and tissues, and upregulated miR-590-5p was associated with increased tumor size, lymph node metastasis, and poor survival. Overexpression of miR-590-5p promoted cell proliferation and invasion and reduced the sensitivity of GC cells to cisplatin and paclitaxel. In contrast, inhibition of miR-590-5p had the opposite effects on GC cells. RECK was identified as a direct target of miR-590-5p. Knockdown of RECK accelerated cell proliferation and motility and decreased the drug sensitivity. Furthermore, reintroduction of RECK inhibited the oncogenic effects of miR-590-5p by suppressing cell proliferation and invasion and increasing drug sensitivity. We found that the AKT/ERK and STAT3 signaling pathways were activated by miR-590-5p overexpression. The chemoresistance of miR-590-5p was also verified by in vivo analysis. Conclusion In summary, we suggest that the miR-590-5p/RECK/AKT axis contributes to GC and may serve as a promising therapeutic target for treatment. PMID:27757042

  18. miR-29b, miR-205 and miR-221 enhance chemosensitivity to gemcitabine in HuH28 human cholangiocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Kinya Okamoto

    Full Text Available BACKGROUND AND AIMS: Cholangiocarcinoma (CCA is highly resistant to chemotherapy, including gemcitabine (Gem treatment. MicroRNAs (miRNAs are endogenous, non-coding, short RNAs that can regulate multiple genes expression. Some miRNAs play important roles in the chemosensitivity of tumors. Here, we examined the relationship between miRNA expression and the sensitivity of CCA cells to Gem. METHODS: Microarray analysis was used to determine the miRNA expression profiles of two CCA cell lines, HuH28 and HuCCT1. To determine the effect of candidate miRNAs on Gem sensitivity, expression of each candidate miRNA was modified via either transfection of a miRNA mimic or transfection of an anti-oligonucleotide. Ontology-based programs were used to identify potential target genes of candidate miRNAs that were confirmed to affect the Gem sensitivity of CCA cells. RESULTS: HuCCT1 cells were more sensitive to Gem than were HuH28 cells, and 18 miRNAs were differentially expressed whose ratios over ± 2log2 between HuH28 and HuCCT1. Among these 18 miRNAs, ectopic overexpression of each of three downregulated miRNAs in HuH28 (miR-29b, miR-205, miR-221 restored Gem sensitivity to HuH28. Suppression of one upregulated miRNA in HuH28, miR-125a-5p, inhibited HuH28 cell proliferation independently to Gem treatment. Selective siRNA-mediated downregulation of either of two software-predicted targets, PIK3R1 (target of miR-29b and miR-221 or MMP-2 (target of miR-29b, also conferred Gem sensitivity to HuH28. CONCLUSIONS: miRNA expression profiling was used to identify key miRNAs that regulate Gem sensitivity in CCA cells, and software that predicts miRNA targets was used to identify promising target genes for anti-tumor therapies.

  19. Lesion-based detection of early chemosensitivity using serial static FDG PET/CT in metastatic colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Buvat, Irene; Necib, Hatem [IMNC UMR 8165 CNRS - Paris 7 and Paris 11 Universities, Orsay cedex (France); Garcia, Camilo; Wagner, Antoine; Vanderlinden, Bruno; Flamen, Patrick [Universite Libre de Bruxelles, Nuclear Medicine Department, Institut Jules Bordet, Brussels (Belgium); Emonts, Patrick [Universite Libre de Bruxelles, Radiology Department, Institut Jules Bordet, Brussels (Belgium); Hendlisz, Alain [Universite Libre de Bruxelles, Digestive Oncology, Institut Jules Bordet, Brussels (Belgium)

    2012-10-15

    Medical oncology needs early identification of patients that are not responding to systemic therapy. {sup 18}F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) performed before and early during treatment has been proposed for this purpose. However, the best way to assess the change in FDG uptake between two scans has not been identified. We studied cutoff thresholds to identify responding tumours as a function of the method used to measure tumour uptake. The study included 28 metastatic colorectal cancer (mCRC) patients who underwent 2 FDG PET/CT scans (baseline and at day 14 of the first course of polychemotherapy). For 78 tumour lesions, 4 standardized uptake value (SUV) indices were measured: maximum SUV (SUV{sub max}) and mean SUV in a region obtained using an isocontour (SUV{sub 40} {sub %}), with each of these SUV normalized either by the patient body weight (BW) or body surface area (BSA). The per cent change and absolute change in tumour uptake between the baseline and the early PET scans were measured based on these four indices. These changes were correlated to the RECIST 1.0-based response using contrast-enhanced CT at baseline and at 6-8 weeks on treatment. The 78 tumours were classified as non-responding (NRL, n = 58) and responding lesions (RL, n = 20). Receiver-operating characteristic (ROC) curves characterizing the performance in NRL/RL classification using early FDG PET uptake had areas under the curve between 0.75 and 0.84, without significant difference between the indices. The cutoff threshold in FDG uptake per cent change to get a 95 % sensitivity of RL detection depended on the way uptake was measured: -14 % (specificity of 53 %) and -22 % (specificity of 64 %) for SUV{sub max} and SUV{sub 40} {sub %}, respectively. Thresholds expressed as absolute SUV decrease instead of per cent change were less sensitive to the SUV definition: an SUV decline by 1.2 yielded a sensitivity of RL detection of 95 % for SUV{sub max} and SUV{sub 40

  20. Over-expression of small ubiquitin-like modifier proteases 1 predicts chemo-sensitivity and poor survival in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Mu Juwei; Zuo Yong; Yang Wenjing; Chen Zhaoli; Liu Ziyuan; Tu Jun; Li Yan

    2014-01-01

    node metastasis (P=0.015),TNM stage (P=-0.001),and SENP1 expression level (P=0.002) were independent prognostic factors for the survival of NSCLC patients.Conclusions SENP1 may be a promising predictor of survival,a predictive factor of chemo-sensitivity for NSCLC patients,and potentially a desirable drug target for lung carcinoma target therapy.

  1. Effects of the pH dependence of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide-formazan absorption on chemosensitivity determined by a novel tetrazolium-based assay.

    Science.gov (United States)

    Plumb, J A; Milroy, R; Kaye, S B

    1989-08-15

    The tetrazolium dye, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), is reduced by live but not dead cells, and this reaction is used as the end point in a rapid drug-screening assay. It can also be used for accurate determinations of drug sensitivity but only if a quantitative relationship is established between cell number and MTT-formazan production. We have shown that reduction of MTT to MTT-formazan by cells is dependent on the amount of MTT in the incubation medium. The concentration required to give maximal MTT-formazan production differs widely between cell lines. The absorption spectrum of MTT-formazan varies with cell number and with pH. At a low cell density or a high pH, the absorption maximum is at a wavelength of 560 to 570 nm. However, at a high cell density or a low pH, there are two absorption maxima; one at 510 nm and a second at about 570 nm. Measurements of absorbance at 570 nm underestimate MTT-formazan production and, hence, cell number at high cell densities. This error can result in a 10-fold underestimation of chemosensitivity. Addition of a buffer at pH 10.5 to the solubilized MTT-formazan product can overcome the effects of both cell density and culture medium on the absorption spectrum. Provided that sufficient MTT is used and the pH of the MTT-formazan product is controlled, dye reduction can be used to estimate cell numbers in a simple chemosensitivity assay the results of which agree well with a commonly used clonogenic assay.

  2. Antitumor Agents 286. Design, Synthesis and Structure-Activity Relationships of 3′R,4′R-Disubstituted-2′,2′-dimethyldihydropyrano[2,3-f]chromone (DSP) Analogs as Potent Chemosensitizers to Overcome Multidrug Resistance

    Science.gov (United States)

    Zhou, Ting; Shi, Qian; Bastow, Kenneth F.; Lee, Kuo-Hsiung

    2010-01-01

    In this study, various 3′R,4′R-disubstituted-2′,2′-dimethydihydropyrano[2,3-f]chromone (DSP) derivatives were discovered as potent chemosensitizers in the treatment of multidrug resistant cancer cells. Twenty-four DSP analogs (5–28) were synthesized and evaluated against a multi-drug resistant (MDR) cell line (KB-Vin) with and without vincristine (VCR). All DSP analogs exhibited low intrinsic cytotoxicity. However, in combination treatment, most DSPs reversed resistance to VCR and lowered the GI50 value of VCR by 12–349-fold. At a concentration of 1μg/mL, three compounds, 11, 14 and 21, fully reversed resistance to VCR in KB-Vin cancer cells, a twofold increase compared to verapamil, a first generation chemosensitizer. Detailed structure-activity relationship (SAR) conclusions were established based on 3′ and 4′ substitutions. Moreover, a preliminary mechanism study indicated that the chemosensitizing activity of DSP analogs results from inhibition of P-glycoprotein (P-gp) over-expressed in MDR cancer cells.1 PMID:21082774

  3. The chemosensitivity of cisplatin on cervical cancer Hela cells influenced by PTEN%PTEN影响宫颈癌Hela细胞对顺铂的化疗敏感性

    Institute of Scientific and Technical Information of China (English)

    范幸; 王比男; 李建军

    2012-01-01

    Objective:To investigate whether the chemosensitivity of cisplatin on cervical cancer Hela cell could be influenced by enhanced PTEN(phosphatase and tensin homology deletion on chromosome ten)expression from transfected PTEN vector.Methods: Three groups of Hela cell were cultured: blank control (non-trans-fection),plasmid control (Hela cells transfected with blank plasmid)and PTEN transfected cells (Hela cells transfected with plasmid contains PTEN gene).RT-PCR and Western blotting were used to detect and assess the expression level of the PTEN mRNA and protein in three groups of Hela cells respectively.Three groups of Hela cells were treated with different concentrations of cisplatin.MTT assay was used to assess chemosensitivity in three groups of Hela cells treated with cisplatin.RT-PCR was used to detect the expression level of phosphatidylinositol 3-kinase (PI3K)in three groups of Hela cell.Results:PTEN expression in PTEN transfected Hela cells was significantly higher than in other two groups(P<0.01).After treated with cisplatin,the growth inhibition ratio of PTEN transfected Hela cells was higher than other groups of cells (P<0.01).PI3K expression was significantly inhibited in PTEN transfected cells than the other two groups (P<0.01).Conclusion:PTEN could increase chemosensitivity of cisplatin on cervical cancer Hela cells,which could be induced by reducing drug resistance from inhibition of PI3K in Hela cells by PTEN.%目的:通过转染PTEN基因表达载体,提高宫颈癌Hela细胞中PTEN的表达水平,观察能否影响Hela细胞对顺铂的敏感性,并探讨其分子学机制.方法:将培养的宫颈癌Hela细胞分为空白对照(未转染质粒的Hela细胞)、质粒对照(转染空质粒的Hela细胞)和PTEN转染(转染PTEN表达载体的Hela细胞)3组.分别用RT-PCR和Western检测各组Hela细胞中PTEN的mRNA和蛋白的表达水平;MTT法检测各组Hela细胞对顺铂的化学敏感性;RT-PCR检测各组Hela细胞中磷脂酰肌醇3-

  4. Study of Gemcitabine chemosensitivity prediction in non-small cell lung cancer%非小细胞肺癌吉西他滨化疗敏感性预测

    Institute of Scientific and Technical Information of China (English)

    吴鹏; 徐佳佳; 王国庆; 冯俊志; 施风

    2014-01-01

    Objective To explore biomarker of Gemcitabine (GEM) chemosensitivity in non-small cell lung cancer (NSCLC). Methods GEM IC50 of 30 NSCLC tissues were detected by susceptibility testing in vitro, mRNA expression of hENT1, dCK ,RRM1 and RRM2 were determined by Realtime-PCR. Results hENT1, dCK, RRM1 or RRM2 expression levels in individual gene had no relationship with the GEM IC50 value (P > 0.05), however, ratio of (hENT1ídCK)/(RRM1íRRM2) was negatively correlated with GEM IC50 value (P 0.05);(hENT1×dCK)/(RRM1×RRM2)值与GEM IC50值呈负相关(P<0.001)。结论(hENT1×dCK)/(RRM1×RRM2)值可作为GEM化疗敏感性预测的潜在标志物。

  5. c-IAP1在食管鳞癌中的表达及其对化疗敏感性的影响%c-IAP1 expression and tumor chemosensitivity in esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    许杨; 刘芳; 周兰萍; 赵晓航

    2011-01-01

    目的:探讨食管鳞癌细胞凋亡抑制蛋白1(c-IAP1)表达与化疗敏感性的相关性.方法:食管鳞癌组织芯片免疫组织化学染色,分析食管鳞癌组织及其配对癌旁食管上皮中c-IAP1的表达和定位及其与肿瘤,临床分级的关系.免疫印迹分析食管癌细胞C-IAP1和Smac表达,用RNA干扰技术敲降Smac表达,MTT法检测细胞对化疗药物敏感性的影响.统计分析采用卡方检验.结果:与癌旁食管上皮(54%,28/52)相比,c-IAP1在食管癌组织中高表达(67%,35/52),但与肿瘤病理分级、年龄和}生别无关.c-IAP1定位于组织细胞质和细胞核,在46%(24/52)的肿瘤组织中,细胞质c-IAP1表达水平显著高于配对癌旁食管上皮4%(2/52),具有统计学意义(P<0.001).食管癌EC0156、KYSE510、KYSE30、KYSE1 80和KYSE170细胞普遍表达c-IAP1,其中KYSE170细胞表达最高.经RNA干扰敲降Smac分子,可显著降低KYSE170细胞对化疗药物的敏感性.结论:c-IAP1蛋白在食管癌组织细胞质中表达率高,经化疗药物处理后,Smac介导c-IAP1降解,增加了食管癌细胞对化疗药物的敏感性,c-IAP1在调控食管癌化疗敏感性中发挥重要作用.%AIM: To investigate the expression of cellular inhibitor of apoptosis protein 1 (c-IAP1) in esophageal squamous cell carcinoma (ESCC) and to evaluate the correlation between c-IAP1 expression and chemosensitivity of ESCC cell lines.METHODS: Immunohistochemistry staining was performed to determine the expression of c-IAP1 in ESCC on tissue microarray.The chisquare test was used to analyze the correlation between c-IAP1 expression and clinicopathologic parameters of ESCC.The expression of c-IAP1and Smac in several ESCC cell lines was detected by Western blot.The chemosensitivity of ESCC cell lines was evaluated by RNA interference with Smac gene expression and MTT assay.RESULTS: c-IAP1 expression was found in 67%(35/52) of ESCC tissue specimens and in 54%(28/52) of tumor-adjacent normal tissue

  6. A proliferation-inducing ligand-binding peptide improves chemo-sensitivity of 5-FU on colorectal LO-VO cells%sAPRIL结合肽对LOVO细胞5-FU化疗敏感性的影响

    Institute of Scientific and Technical Information of China (English)

    何小庆; 柳芳; 许雯; 何美蓉

    2015-01-01

    目的:增殖诱导配体(APRIL)与结直肠癌细胞对5-氟尿嘧啶(5-FU)的耐药性密切相关。我们前期已利用噬菌体随机肽库技术成功筛选并人工合成与sAPRIL有高亲和力的结合肽。本研究旨在探讨sAPRIL结合肽对结直肠癌LOVO细胞5-FU化疗敏感性的影响。方法将LOVO细胞分为PBS组、5-FU组、sAPRIL结合肽+5-FU组。采用CCK-8法检测细胞增殖、流式细胞仪测定细胞周期及细胞凋亡。结果5-FU组和sAPRIL结合肽+5-FU组增殖抑制率分别为(37.62±7.07)%、(63.05±2.15)%;流式细胞仪检测各组的细胞周期显示5-FU组阻滞在S期,sAPRIL结合肽+5-FU组阻滞在G0/G1期和S期,且S期阻滞效应显著强于5-FU组;三组细胞凋亡率分别为(0.21±0.09)%、(12.80±0.30)%、(17.1±0.66)%。结论 sAPRIL结合肽能增强结直肠癌LOVO细胞对5-FU的化疗敏感性,有望成为结直肠癌靶向治疗的新型候选制剂。%Objective This study aimed to verify if the sAPRIL-binding peptide can enhance chemo-sensitivity of 5-FU on colorectal cancer cells. Methods LOVO cells were divided into three groups: PBS, 5-FU, and sAPRIL-binding peptide plus 5-FU. The cell growth inhibition rate was detected by CCK-8 assay, and the cell cycle and cell apoptosis were detected by flow cytometry. Results The cell growth inhibition rate was (0±0)%in PBS group, (37.62±7.07)%in 5-FUgroup, (63.05±2.15)%in sAPRIL-binding peptide plus 5-FU group, respectively. In 5-FU group, cell cycle was arrested at S phase;and in sAPRIL-binding peptide plus 5-FU group, in sAPRIL-binding peptide plus 5-FU group, cell cycle was arrested at both G0/G1 and S phases ( more markedly at S phase compared with 5-FU alone). The percentage of early apoptotic cells was (0.21±0.09)%in PBS group, (12.80±0.30)%in 5-FUgroup, and (17.1±0.66)%in sAPRIL-binding peptide plus 5-FU group, respectively. Conclusions The sAPRIL-binding peptide can enhance chemo-sensitivity of 5-FU

  7. Rapid in vivo Taxotere quantitative chemosensitivity response by 4.23 Tesla sodium MRI and histo-immunostaining features in N-Methyl-N-Nitrosourea induced breast tumors in rats

    Directory of Open Access Journals (Sweden)

    Wu Ed X

    2005-08-01

    Full Text Available Abstract Background Sodium weighted images can indicate sodium signal intensities from different features in the tumor before and 24 hours following administration of Taxotere. Aim To evaluate the association of in vivo intracellular sodium magnetic resonance image intensities with immuno-biomarkers and histopathological features to monitor the early tumor response to Taxotere chemotherapy in Methyl-Nitroso-Urea induced rat xenograft breast tumors. Methods and Materials Methyl-Nitroso-Urea (MNU induced rat xenograft breast tumors were imaged for sodium MRI and compared with tumor histology, immunostaining after 24 hours chemotherapy. Results Sodium MRI signal intensities represented sodium concentrations. Excised tumor histological sections showed different in vitro histological end points i.e. single strand DNA content of cell nuclei during cell cycle (G1/S-G2/M, distinct S or M histograms (Feulgen labeling to nuclear DNA content by CAS 200, mitotic figures and apoptosis at different locations of breast tumors. Necrosis and cystic fluid appeared gray on intracellular (IC sodium images while apoptosis rich regions appeared brighter on IC sodium images. After 24 hours Taxotere-treated tumors showed lower 'IC/EC ratio' of viable cells (65–76% with higher mitotic index; apoptotic tumor cells at high risk due to cytotoxicity (>70% with high apoptotic index; reduced proliferation index (270 vs 120 per high power field associated with enhanced IC sodium in vivo MR image intensities and decreased tumor size (3%; p in vivo associated with apoptosis and different pre-malignant features within 24 hours of exposure of cancer cells to anti-neoplastic Taxotere drug. Conclusion Sodium MRI imaging may be used as in vivo rapid drug monitoring method to evaluate Taxotere chemosensitivity response associated with neoplasia, apoptosis and tumor histology features.

  8. Cancer cells mimic in vivo spatial-temporal cell-cycle phase distribution and chemosensitivity in 3-dimensional Gelfoam® histoculture but not 2-dimensional culture as visualized with real-time FUCCI imaging.

    Science.gov (United States)

    Yano, Shuya; Miwa, Shinji; Mii, Sumiyuki; Hiroshima, Yukihiko; Uehara, Fuminaru; Kishimoto, Hiroyuki; Tazawa, Hiroshi; Zhao, Ming; Bouvet, Michael; Fujiwara, Toshiyoshi; Hoffman, Robert M

    2015-01-01

    The phase of the cell cycle can determine whether a cancer cell can respond to a given drug. We previously reported monitoring of real-time cell cycle dynamics of cancer cells throughout a live tumor, intravitally in live mice, using a fluorescence ubiquitination-based cell-cycle indicator (FUCCI). Approximately 90% of cancer cells in the center and 80% of total cells of an established tumor are in G0/G1 phase. Longitudinal real-time imaging demonstrated that cytotoxic agents killed only proliferating cancer cells at the surface and, in contrast, had little effect on quiescent cancer cells, which are the vast majority of an established tumor. Moreover, resistant quiescent cancer cells restarted cycling after cessation of chemotherapy. These results suggested why most drugs currently in clinical use, which target cancer cells in S/G2/M, are mostly ineffective on solid tumors. In the present report, we used FUCCI imaging and Gelfoam® collagen-sponge-gel histoculture, to demonstrate in real time, that the cell-cycle phase distribution of cancer cells in Gelfoam® and in vivo tumors is highly similar, whereby only the surface cells proliferate and interior cells are quiescent in G0/G1. This is in contrast to 2D culture where most cancer cells cycle. Similarly, the cancer cells responded similarly to toxic chemotherapy in Gelfoam® culture as in vivo, and very differently than cancer cells in 2D culture which were much more chemosensitive. Gelfoam® culture of FUCCI-expressing cancer cells offers the opportunity to image the cell cycle of cancer cells continuously and to screen for novel effective therapies to target quiescent cells, which are the majority in a tumor and which would have a strong probability to be effective in vivo.

  9. Wild type p53 increased chemosensitivity of drug-resistant human hepatocellular carcinoma Be17402 / 5-FU cells%野生型p53增强药物耐药的人肝癌细胞Bel7402/5-FU的化疗敏感性

    Institute of Scientific and Technical Information of China (English)

    李玉秀; 林志彬; 谭焕然

    2004-01-01

    AIM: To study the effect of wild type (wt) p53 gene transfection on drug resistant human hepatocellular carcinoma (HCC) cells induced by 5-Fluorouracil (5-FU). METHODS: The cytotoxicity of anticancer drugs on Be17402 and Be17402/5-FU cells was assessed using SRB assay. p53 expression was detected at its mRNA level by RT-PCR assay and at its protein level Western blot or immunocytochemistry assay in Be17402/5-FU cells transfected with either control vector or wt p53. AnnexinV-FITC/PI double labeled assay was performed to detect apoptosis. The chemosensitivity of Be17402/5-FU cells transfected with wt p53 was assessed using SRB assay. RESULTS: Be17402/5-FU cells exhibited cross-resistance to vincristine, doxorubicin, paclitaxel, and so on. wt p53 gene transfection upregulated the expression of p53 in Be17402/5-FU cells. wt p53 was able to greatly inhibit cell proliferation and significantly induce apoptosis in Bel7402/5-FU cells. Moreover, wt p53 gene transfection increased the chemosensitivity of Be17402/5-FU cells to some anticancer drugs. CONCLUSION: These results indicated that the wt p53 gene transfection not only induced suppression of cell growth, but also increased the sensitivity of Be17402/5-FU cells to 5-FU, vincristine, and doxorubicin.

  10. Development and molecular characterization of polymeric micro-nanofibrous scaffold of a defined 3-D niche for in vitro chemosensitivity analysis against acute myeloid leukemia cells

    Directory of Open Access Journals (Sweden)

    Nair MS

    2015-05-01

    Full Text Available Maya S Nair,1 Ullas Mony,1 Deepthy Menon,1 Manzoor Koyakutty,1 Neeraj Sidharthan,2 Keechilat Pavithran,2 Shantikumar V Nair,1 Krishnakumar N Menon11Amrita Centre for Nanosciences and Molecular Medicine, 2Department of Oncology, Amrita Institute of Medical Sciences and Research Centre, Amrita Vishwa Vidyapeetham University, Kerala, IndiaAbstract: Standard in vitro drug testing employs 2-D tissue culture plate systems to test anti-leukemic drugs against cell adhesion-mediated drug-resistant leukemic cells that harbor in 3-D bone marrow microenvironments. This drawback necessitates the fabrication of 3-D scaffolds that have cell adhesion-mediated drug-resistant properties similar to in vivo niches. We therefore aimed at exploiting the known property of polyurethane (PU/poly-L-lactic acid (PLLA in forming a micro-nanofibrous structure to fabricate unique, not presented before, as far as we are aware, 3-D micro-nanofibrous scaffold composites using a thermally induced phase separation technique. Among the different combinations of PU/PLLA composites generated, the unique PU/PLLA 60:40 composite displayed micro-nanofibrous morphology similar to decellularized bone marrow with increased protein and fibronectin adsorption. Culturing of acute myeloid leukemia (AML KG1a cells in FN-coated PU/PLLA 60:40 shows increased cell adhesion and cell adhesion-mediated drug resistance to the drugs cytarabine and daunorubicin without changing the original CD34+/CD38-/CD33- phenotype for 168 hours compared to fibronectin tissue culture plate systems. Molecularly, as seen in vivo, increased chemoresistance is associated with the upregulation of anti-apoptotic Bcl2 and the cell cycle regulatory protein p27Kip1leading to cell growth arrest. Abrogation of Bcl2 activity by the Bcl2-specific inhibitor ABT 737 led to cell death in the presence of both cytarabine and daunorubicin, demonstrating that the cell adhesion-mediated drug resistance induced by Bcl2 and p27

  11. Heterogeneity of chemosensitivity in six clonal cell lines derived from a spontaneous murine astrocytoma and its relationship to genotypic and phenotypic characteristics.

    Science.gov (United States)

    Bradford, R; Koppel, H; Pilkington, G J; Thomas, D G; Darling, J L

    1997-09-01

    Heterogeneity in drug sensitivity must, in part, account for the relative lack of success with single agent chemotherapy for glioblastoma multiforme (GBM). In order to develop in vitro model systems to investigate this, clones derived from the VM spontaneous murine astrocytoma have been characterised with regard to drug sensitivity. Six clonal cell lines have been tested for sensitivity to a panel of cytotoxic drugs using an intermediate duration 35S-methionine uptake assay. These lines have previously been extensively characterised with regard to morphological, antigenic, kinetic, tumourigenic potential in syngeneic animals and chromosomal properties and display considerable heterogeneity. The present study indicates that heterogeneity extends to sensitivity to all classes of cytotoxic drugs. The greatest difference in sensitivity between the clones was seen in response to cell cycle-specific drugs like the Vinca alkaloids (14-fold and 20-fold for vincristine (VCR) and vindesine (VIND) respectively), while the nitrosoureas, CCNU and BCNU displayed a smaller fold difference in sensitivity (4.3 and 3.6-fold difference respectively). All the clones were considerably more resistant to the adriamycin (ADM), cis-platinum (C-PLAT) and the Vinca alkaloids than the parental cell line although the difference in sensitivity between the clones and parental cell line were less marked for the nitrosoureas and procarbazine (PCB). It has also been possible to examine the relationship between drug sensitivity and the phenotypic and genotypic properties of these clonal cell lines. There is a relationship between chromosome number and sensitivity of a wide variety of cytotoxic drugs including the nitrosoureas, Vinca alkaloids, PCB, C-PLAT, BLEO but not ADR or 5-FU. Clones with small numbers of chromosomes were more resistant than clones with gross polyploidy. Similarly, sensitivity to Vinca alkaloids and ADM, but not other classes of drugs, was greatest in cells with numerous

  12. Chitosan coated polylactic acid nanoparticle-mediated combinatorial delivery of cisplatin and siRNA/Plasmid DNA chemosensitizes cisplatin-resistant human ovarian cancer cells.

    Science.gov (United States)

    Babu, Anish; Wang, Qi; Muralidharan, Ranganayaki; Shanker, Manish; Munshi, Anupama; Ramesh, Rajagopal

    2014-08-01

    Development of resistance toward anticancer drugs results in ineffective therapy leading to increased mortality. Therefore, overriding resistance and restoring sensitivity to anticancer drugs will improve treatment efficacy and reduce mortality. While numerous mechanisms for drug resistance in cancer have previously been demonstrated, recent studies implicate a role for proteasome and the autophagy regulatory protein P62/SQSTM1 (P62) in contributing to drug resistance. Specifically, reduction in the expression of the β5 subunit of the proteasome and/or enhanced P62 protein expression is known to contribute to cancer drug resistance such as cisplatin (CDDP) in ovarian cancer cells. Therefore, we hypothesized that restoration of β5 expression and/or suppression of P62 protein expression in CDDP-resistant ovarian cancer cells will lead to restoration of sensitivity to CDDP and enhanced cell killing. To test our hypothesis we developed a biodegradable multifunctional nanoparticle (MNP) system that codelivered P62siRNA, β5 plasmid DNA, and CDDP and tested its efficacy in CDDP resistant 2008/C13 ovarian cancer cells. MNP consisted of CDDP loaded polylactic acid nanoparticle as inner core and cationic chitosan (CS) consisting of ionically linked P62siRNA (siP62) and/or β5 expressing plasmid DNA (pβ5) as the outer layer. The MNPs were spherical in shape with a hydrodynamic diameter in the range of 280-350 nm, and demonstrated encapsulation efficiencies of 82% and 78.5% for CDDP and siRNA respectively. MNPs efficiently protected the siRNA and showed superior serum stability compared to naked siRNA as measured by gel retardation and spectrophotometry assays. The MNPs successfully delivered siP62 and pβ5 to cause P62 knockdown and restoration of β5 expression in 2008/C13 cells. Combined delivery of siP62, pβ5, and CDDP using the MNPs resulted in a marked reduction in the IC50 value of CDDP in 2008/C13 cells from 125 ± 1.3 μM to 98 ± 0.6 μM (P < 0.05; 21

  13. 芹菜素对人鼻咽癌CNE-2Z细胞化疗敏感性的增强作用%Chemosensitization effects of apigenin on cisplatin in human nasopharyngeal carcinoma CNE-2Z cells

    Institute of Scientific and Technical Information of China (English)

    李明勇; 黄培春

    2012-01-01

    目的 观察芹菜素(AP)能否增强人鼻咽癌CNE-2Z细胞对顺铂 (DDP)的化疗敏感性.方法 采用MTT法对CNE-2Z细胞的增殖抑制率进行检测,中效原理法对联合用药的相互作用进行分析判断;采用流式细胞术和PI/Hoechst33258荧光双染法检测细胞凋亡;RT-PCR法检测凋亡相关基因bcl-2、bax mRNA表达的改变.结果 AP、DDP单用及合用均明显抑制CNE-2Z细胞的生长,且呈剂量依赖性关系,两药合用时在中、高浓度呈协同效应;流式细胞术和荧光双染法结果表明低浓度AP联合DDP更能明显促进肿瘤细胞的凋亡;与单独用药组比较,RT-PCR结果显示联合用药组bcl-2 mRNA表达明显降低,而bax mRNA表达明显增高.结论 芹菜素可增强顺铂对CNE-2Z细胞增殖的抑制作用和诱导凋亡作用,其机制可能与上调bax和下调bcl-2的表达,导致Bcl-2/Bax比值下降有关.%Aim To observe the chemosensitization effects of apigenin on cisplatin in human nasopharynge-al carcinoma CNE-2Z cells. Methods The inhibitory effects of apigenin, cisplatin and apigenin combined with cisplatin on the growth of CNE-2Z cells were determined by MTT assay. The combination effect was determined by using the method of median-effect principle. Cell apoptosis was detected by flow cytometry and Hoechst3358/PI fluorescent staining. The changes of bcl-2,bax mRNA level were quantified by RT-PCR. Results Apigenin and cisplatin ( individual or combined ) significantly inhibited the growth of CNE-2Z cells in a dose-dependent manner. The interaction of the two drugs was synergistic at medium or high concentrations. The results of flow cytometry and PI/Ho-echst33258 fluorescent staining showed that the combinative application group ( at low concentrations ) could significantly induce cells apoptosis. Compared to apigenin or cisplatin treatment group, the mRNA expression of bax was obviously up-regulated as well as that of bcl-2 was significantly down-regulated in the

  14. Flight Test Guide (Part 61 Revised): Instrument Pilot: Helicopter.

    Science.gov (United States)

    Federal Aviation Administration (DOT), Washington, DC. Flight Standards Service.

    The guide provides an outline of the skills required to pass the flight test for an Instrument Pilot Helicopter Rating under Part 61 (revised) of Federal Aviation Regulations. General procedures for flight tests are described and the following pilot operations outlined: maneuvering by reference to instruments, IFR navigation, instrument…

  15. Effects of methylseleninic acid on inhibition and chemosensitization of triple-negative breast cancer cells%甲基硒酸对人三阴性乳腺癌细胞的抑制和化疗增敏作用

    Institute of Scientific and Technical Information of China (English)

    邱万寿; 唐勇; 吴珏堃; 刘威; 李玺

    2013-01-01

    Objective To investigate the effects of methylseleninic acid on chemosensitization of triple-negative breast cancer (TNBC) cells and the molecular mechanism.Methods Methylseleninic acid (MSA) (2.5,3.5,4.0 μmol/L) in combination with paclitaxel,doxorubicin or malondialdehyde (MDA)-treated MB-231 cells were cultured separately.Cell counting kit-8 (CCK-8) assay was applied to detect the inhibition of cell proliferation rate by chemotherapy drugs use alone or in combination with MSA,and the combined index was calculated to explore the impact of the function of MSA on the efficacy of chemotherapy drugs.Annexin V-FITC/propidium iodide (PI) double staining was applied to detect apoptosis,flow cytometry to examine cell cycle,and Western blotting to analyze thes histone deacetylase-6 (HDAC-6) expression.Results The cell proliferation rate of chemotherapy drugs in combination with MSA was decreased as compared with chemotherapy drugs used alone,suggesting the synergetic effects of MSA and chemotherapy drugs.The combined use of paclitaxel with MSA could significantly increase the number of cells in G2/M phase (P < 0.05),that of doxorubicin with MSA could significandy increase the number of cells in S-phase cells (P < 0.05),and the prompt MSA enhanced the effect of anticancer drugsinduced cell cycle arrest.MSA,paclitaxel and doxorubicin could induce apoptosis of TNBC cells.The apoptosis rate in MSA + chemotherapy groups was significantly increased as compared with monotherapy group and the control group.Chemotherapy drugs alone did not affect the expression of HDAC-6,and MSA used alone or incombination with chemotherapy drugs could significantly inhibit the HDAC-6 expression.Conclusion MSA enhanced anticancer drugs-induced cell cycle arrest and apoptosis so as to improve the efficacy of chemotherapy drugs probably by regulating the HDAC-6 expression.%目的 探讨甲基硒酸(MSA)对人三阴性乳腺癌(TNBC)的化疗增敏作用及其分子机制.方法 分别采用2.5

  16. Uso de teste de químio-sensibilidade para escolha da quimioterapia adjuvante no câncer gástrico avançado Use of the chemosensitivity test to choose appropriate adjuvant chemotherapy for advanced gastric cancer

    Directory of Open Access Journals (Sweden)

    Wilson Shinjiro Matsuzaki

    2006-08-01

    Full Text Available OBJETIVO: Introduzir e familiarizar em nosso meio o uso do teste de químio-sensibilidade MTT avaliando a ação de agentes quimioterápicos sobre células tumorais de 30 doentes com câncer gástrico avançado. Correlacionar os resultados do teste MTT com os aspectos clínicos, anátomo-patológicos e estádio utlizando a mesma metodologia do estudo realizado em pacientes japoneses na Universidade de Keio, Japão. MÉTODO: Foi realizado o teste MTT em tumores de 30 pacientes com diagnóstico de adenocarcinoma gástrico, submetidos ao tratamento cirúrgico no Departamento de Cirurgia da Faculdade de Ciências Médicas da Santa Casa de São Paulo. Foram estudados in vitro os seguintes agentes quimioterápicos: mitomicina C, doxorrubicina, cisplatina e 5-fluorouracil. RESULTADOS: Os índices de atividade sobre células tumorais foram: 16,6% para a mitomicina C, 10,0% para a doxorrubicina, 6,6% para a cisplatina e 6,6% para o 5-fluorouracil. Os resultados do teste MTT não tiveram correlação com a idade, sexo, aspectos microscópicos e estádio (p0,05. CONCLUSÕES: A ação dos agentes quimioterápicos estudados sobre células tumorais do câncer gástrico foi baixa. Os resultados da ação dos quimioterápicos in vitro não apresentou correlação estatística com a idade, sexo, aspectos microscópicos e estádio destes doentes. Utilizando a mesma metodologia, tanto em nosso meio como em pacientes japoneses, a quimio-sensibilidade se mostrou baixa em ambos os estudos, podendo-se deduzir também que os resultados da químiosensibilidade independe da etnia. Com o surgimento de novos agentes quimioterápicos, a expectativa é grande para melhores resultados na prática clínica. Com a utilização e difusão do teste MTT em nosso meio, poder-se-á criar protocolos e estudos multicêntricos para selecionar os quimioterápicos a serem utlizados.BACKGROUND: Utilizing the MTT chemosensitivity test to evaluated the action of chemotherapeutic agents on

  17. A novel rat tail collagen gel droplet method for three-dimensional cell culture and che-mosensitivity test in gastric cancer%一种新型的鼠尾胶滴胃癌细胞三维培养模型的建立与药敏初探

    Institute of Scientific and Technical Information of China (English)

    辛恺; 魏嘉; 沈洁; 刘宝瑞

    2015-01-01

    Objective:To establish a novel gastric cancer cell 3D culture model,and further investigate the possi-bility of the chemosensitivity test based on that model. Methods:We choose rat-tail collagen to build a cell-embed-ded droplet and we confirmed that the BGC823 gastric cell lines were grown in the droplet,in an aggregation growth mode for 8 days. The colonies in the droplet were then stained by neutral red staining solution. An inverted microscope with CCD camera was used to acquire high-definition images. We further calculated the integrated optical density ( IOD)of stained area in droplet image,and compared the surviving rate of two group treated by CDDP with different concentrations. Results:we successfully established a novel gastric cancer cell 3D culture model. Conclusion:The pssibility of further chemosensitivity test based on that model was confirmed in preliminary.%目的:建立一种简便的鼠尾胶原包被的胃癌细胞体外三维培养和药敏技术,初步评估该方法的稳定性和可行性。方法:以国产鼠尾胶原溶液为原料,制备包裹有胃癌细胞株的胶滴,在培养基中培养8天,观察BGC823细胞株在胶滴中的生长情况。接着对胶滴中的细胞克隆进行染色,捕捉胶滴中的数字图像,利用软件计算图像内染色区域的积分光密度值( integrated optical density,IOD),对胶滴中的细胞活力进行定量;最后初步计算两种不同浓度的顺铂组BGC823细胞株的存活率。结果:成功建立一种新型的胃癌细胞鼠尾胶滴三维培养模型。结论:初步证实了基于此模型进行后续药敏实验的可行性。

  18. Discussion on influence and mechanism of curcumin combined cisplatin on chemosensitivity of Hela cells%姜黄素联合顺铂对宫颈癌Hela细胞化疗敏感性的影响及机制探讨

    Institute of Scientific and Technical Information of China (English)

    冯冰霜; 雷张涛; 张春华; 刘正香; 朱俊峰

    2015-01-01

    Objective To investigate the influence and mechanism of curcumin combined cisplatin on the chemosensitivity of Hela cells, and to provide reference for clinical practices. Method The cervical cancer Hela cells were selected for In vitro development, curcumins with different concentrations (compatible with cisplatin) were utilized to intervene cervical cancer Hela cells, MTT method was used to determine the proliferation inhibition rate of medicine on Hela cells, RT-PCR and Western blot method were utilized to determine expression details of p53 protein, the influence and mechanism of curcumin combined cisplatin on cervical cancer Hela cells chemotherapy sensitivity were explored. Result The inhibition rate and rate of apoptosis-inducing against the proliferation of cervical cancer Hela cells in the experimental group were signiifcantly higher than control group and curcumin group (P<0.05). Expressions of COX-2, Caspase-3 and Maspin in experimental group were signiifcantly better than control group and curcumin group (P < 0.05). Expressions of p53 proteins within 24 hours upon the action of curcumin with different concentrations increased with the increase in the concentration of with curcumin, and the difference was statistically signiifcant (P<0.05). Conclusion The curcumin combined cisplatin delivers signiifcant inlfuences on the chemosensitivity of Hela cells, it can inhibit the proliferation of Hela cells and induce the apoptosis of cellsand increase the sensitivity, which may be realized by increasing expressions of p53 gene.%目的:研究姜黄素联合顺铂对宫颈癌Hela细胞化疗敏感性的影响以及机制,为临床实践提供参考和借鉴。方法选用人宫颈癌Hela细胞进行体外培养,利用不同浓度姜黄素(配伍顺铂方案)干预人宫颈癌Hela细胞,采用MTT法检测药物对宫颈癌Hela细胞的增殖抑制率;采用RT-PCR和Western blot法检测p53蛋白的表达情况,探讨姜黄素联合顺铂方案对

  19. Clinical research on chemotherapy of recurrent and refractory non-Hodgkin lymphoma directed by ATP bioluminescence chemosensitivity assay in vitro%三磷酸腺苷生物荧光法体外药敏试验指导复发或难治性非霍奇金淋巴瘤化疗的临床研究

    Institute of Scientific and Technical Information of China (English)

    杨磊; 宋诸臣; 徐小红; 蒋斌; 彭春雷; 魏金芝

    2011-01-01

    Objective To investigate the clinical value of ATP bioluminescence tumor chemosensitivity assay (ATP-TCA) for recurrent and refractory non-Hodgkin lymphoma (NHL) specimens in vitro.Methods Thirty-four freshly taken recurrent and refractory NHL specimens were tested in vitro for cancer chemosensitivity by ATP-TCA.Results Drug sensitivity of NHL specimens had heterogeneity.Different drugs had different tumor growth inhibition ratio in vitro.Response rate (RR) of the patients receiving chemotherapy according to in vitro assay was 82.4 % (28/34),complete response rate (CR) was 52.9 % (18/34).In DICE group RR was 60.0 % (18/30),CR rate was 33.3 % (10/30).In GDP group RR was 62.3 % (33/53),CR rate was 26.4 % (14/53).In ATP-TCA group RR was significantly higher than those in DICE and GDP groups (x2 =3.93,P =0.047; x2 =3.98,P =0.046).Conclusion The results of ATP-TCA assay are correlated well with clinical treatment responses.The assay may be an important and useful method for individual-based chemotherapy of cancers.%目的 探讨三磷酸腺苷生物荧光法(ATP-TCA)体外药敏试验在复发或难治非霍奇金淋巴瘤( NHL)治疗中的临床应用价值.方法 应用ATP-TCA技术对复发或耐药淋巴瘤患者术后新鲜组织标本共34例进行体外药敏试验,观察用敏感药物化疗疗效.结果 淋巴瘤标本的药物敏感性具有个体差异性,不同化疗药物的体外抑瘤活性不同.药敏试验组总有效率(RR)为82.4%(28/34),完全缓解(CR)率为52.9%(18/34);DICE化疗组RR为60.0%( 18/30),CR率为33.3%(10/30);GDP化疗组RR为62.3%(33/53),CR率为26.4%(14/53).药敏试验组的RR与DICE组及GDP组相比,差异有统计学意义(x2=3.93,P=0.047; x2=3.98,P=0.046).结论 ATP-TCA体外药敏检测结果与临床治疗反应有很好的相关性,是开展肿瘤个体化化疗的一种重要的体外药物筛选方法.

  20. 锌原卟啉ZnPP Ⅸ对Bel/FU肝癌耐药细胞株p-糖蛋白及化疗敏感性的影响%ZnPP Ⅸ's effect on p-glycoprotein expression and chemosensitivity of drug-resistant hepatic carcinoma cell line

    Institute of Scientific and Technical Information of China (English)

    张隽开; 王忠裕; 巩鹏; 罗海峰; 牟国煜

    2011-01-01

    目的:评估锌原卟啉(ZnPP)Ⅸ对Bel/FU肝癌耐药细胞株P-糖蛋白(p-glycoprotein,p-GP)的影响,探讨ZnPP Ⅸ作为化疗耐药逆转剂可能性及相关作用机制.方法:不同浓度的ZnPP Ⅸ作用于Bel/FU肝癌化疗耐药细胞株,MTT法检测细胞株对化疗药物的半数抑制浓度(IC50)、Western blot检测p-GP表达量、罗丹明潴留试验检测p-GP药物外排功能.结果:ZnPP Ⅸ作用于Bel/FU细胞诱导24 h后,化疗药物IC50值均显著降低,P-GP表达量明显降低(P均<0.01),p-GP药物外排功能减弱.结论:ZnPP Ⅸ可通过影响p-GP蛋白质水平的表达,减弱P-GP药物外排功能,使肝癌耐药细胞株的化疗敏感性降低;ZnPP Ⅸ可作为一种潜在的化疗耐药逆转剂.%Objective: To evaluate ZnPP IX's effect on the expression of p-glycoprotein (P-GP)and the chemosensitivity of drug-resistant hepatic carcinoma Bel/Fu cell line,and to explore the relevant regulating mechanism. Methods: After Bel/FU cells being induced by different gradient concentrations of ZnPP IX for 24 h, MTT assay was carried out to detect the sensitivity of Bel/Fu:P-glycoprotein protein level was determined by Western blot analysis; Rhodamine123 retention fluorescent intensity measured by flow cytometry was used to detect the function of p-GP. Results:After Bel/FU cells being dealt with ZnPP IX for 24 h,there were significant differences in 50% inhibiting concentration (IC50) of chemical drugs between control groups and contrast group. IC50 of control groups decreased obviously. Meanwhile, p-GP protein level expression in the cells of control groups were observably lower than that in contrast group. The curve of Rhodamine123 retention fluorescent intensity in the control cells shift to the right, which indicated that the efflux pump function of p-GP was weakened. Conclusions: ZnPP IX can increase the chemosensitivity of Bel/FU cell line,which relates with its action in down-regulation of P-glycoprotein expression. ZnPP IX may be

  1. Ki-67对三阴性乳腺癌新辅助化疗敏感性预测作用的Meta分析%Predict function of Ki-67 to chemosensitivity of neoadjuvant chemotherapy in triple-negative breast cancer : a meta-analysis

    Institute of Scientific and Technical Information of China (English)

    章国晶; 刘兆喆; 郭放; 谢晓冬

    2012-01-01

    目的:评价新辅助化疗中Ki-67的表达情况对三阴性乳腺癌(TNBC)获得病理完全缓解(pCR)的预测作用.方法:通过互联网检索相关文献,应用Review Manager软件对数据进行处理,系统评价Ki-67表达情况与TNBC在新辅助化疗中获得pCR的关系.结果:Ki 67基因高表达的TNBC患者pCR率明显高于Ki-67基因低表达的TNBC患者,总体合并优势比(OR)为7.35,95%CI:2.39~22.60,文献之间无明显异质性,无明显发表偏倚.结论:Ki-67可作为新辅助化疗中预测TNBC化疗敏感性的标志.%OBJECTIVE; The meta-analysis was conducted to estimate the predict function of Ki-67 to pathological complete response (pCR) rates of neoadjuvant chemotherapy in triple-negative breast cancer(TNBC). METHODS: Relevant literatures were selected by searching the internet. Review manager software was used to merge extractive data. RESULTS: The pCR rates were much higher in Ki-67 high expression TNBC than that in Ki-67 low expression TNBC. The merged odds ratio(OR) was 7. 35(95% confidence interval: 2. 39 - 22. 60). No obvious statistical heterogeneity and publication bias were detected. CONCLUSION: Ki-67 was a predictor to chemosensitivity of neoadjuvant chemotherapy in TNBC.

  2. Application value of ATP based bioluminescence tumor chemo-sensitivity assay in the chemotherapy for ascites caused by recurrent ovarian cancer%ATP生物荧光肿瘤药敏在复发卵巢癌并腹水化疗中的应用价值

    Institute of Scientific and Technical Information of China (English)

    Kaijian Lei; Yuming Jia; Biao Wei; Yongxiang Xiong; Jing Wang

    2008-01-01

    Objective:To investigate the clinical value and application of ATP based bioluminescence tumor chemo-sensitivity assay (ATP-TCA) in the chemotherapy for ascites caused by recurrent ovarian cancer.Methods:More than 10 kinds of chemotherapeutic drugs or combinations were applied and 35 ascites specimens from recurrent ovarian cancer were analyzed by ATP-TCA.Sensitivity of chemotherapeutic drugs was assessed.After 2-4 chemotherapeutic cycles,clinical outcomes were analyzed,which were compared with those of 40 cases by empirical regimens.Results:32 of 35 specimens were evaluated with an overall evaluation rate of 91%.The assay results suggested that chemo-naive patients responded to chemotherapeutic drugs with individualized profiles.The sensitivity rates of GEM,EPI,OXA,DDP,CBP,ADM,VP-16,CTX,NVB,5-FU,PTX and TXT were 40%,30%,33%,29%,33%,38%,25%,33%,38%,33%,25% and 20%,respectively.While the sensitivity rates of combinations GEM + EPI,GEM + CBP,GEM + DDP,NVB + DDP,CTX + ADM + DDP,CTX + ADM,DDP + VP-18,OXA + 5-FU,VP-16 + IFO,PTX + DDP,TXT + CBP,VCR + CTX + MTX,DDP + CPT-11,OXA + CPT-11,and DTIC + CTX were 47%,50%,36%,44%,30%,33%,27%,33%,40%,27%,23%,14%,28%,30% and 17%,respectively.In vitro results correlated well with clinical outcomes.Objective response rate (RR) in chemo-sensitivity-guided group was of significance compared with that in empirical-regimen-guided group.Conclusion:ATP-TCA is a choice for the screening of chemotherapeutic drugs against ascites caused by recurrent ovarian cancer with excellent sensitivity and reliability.ATP-TCA assay results correlate well with clinical outcomes,suggesting its clinical value in the management of difficult-to-manage therapeutic situations such as ascites in recurrent ovarian cancer.

  3. Quimiossensibilidade durante exercício na insuficiência cardíaca: respostas ventilatórias, cronotrópicas e neurohormonais Quimiosensibilidad durante ejercicio en la insuficiencia cardíaca: respuestas ventilatorias, cronotrópicas y neurohormonales Exercise chemosensitivity in heart failure: ventilatory, chronotropic and neurohormonal responses

    Directory of Open Access Journals (Sweden)

    Lídia Zytynski Moura

    2010-09-01

    Full Text Available FUNDAMENTO: Insuficiência cardíaca (IC está associada com aumento da quimio-sensibilidade periférica e central em repouso, que pode estar correlacionada com um aumento na resposta ventilatória durante exercício. Entretanto, SUS sensibilidade na IC durante o exercício ainda não foi reportada. OBJETIVO: Testar se o estímulo dos quimiorreceptores centrais e periféricos em pacientes com IC pode modular respostas ventilatórias, cronotrópicas e neurohormonais durante exercício submáximo. MÉTODOS: Investigamos a quimio-sensibilidade central e periférica em 15 pacientes com insuficiência cardíaca (IC e 7 controles normais (C, comparando a resposta durante 3 testes de caminhada de 6 minutos (TC6M, realizado em esteira ergométrica com: ar ambiente, em hipóxia e em hipercapnia (em ordem randômica. RESULTADOS: FR em ar ambiente nos grupos C e IC foi 17±2 e 22±2 (pFUNDAMENTO: La insuficiencia cardíaca (IC está asociada con aumento de la quimiosensibilidad periférica y central en reposo, que puede estar correlacionada con un aumento en la respuesta ventilatoria durante ejercicio. Mientras tanto, SUS sensibilidad en la IC durante el ejercicio aun no fue reportada. OBJETIVO: Verificar si el estímulo de los quimiorreceptores centrales y periféricos en pacientes con IC puede modular respuestas ventilatorias, cronotrópicas y neurohormonales durante ejercicio submáximo. MÉTODOS: Investigamos la quimiosensibilidad central y periférica en 15 pacientes con insuficiencia cardíaca (IC y 7 controles normales (C, comparando la respuesta durante 3 tests de caminata de 6 minutos (TC6M, realizado en cinta ergométrica con: aire ambiente, en hipoxia y en hipercapnia (en orden randómico. RESULTADOS: FR en aire ambiente en los grupos C y IC fue 17±2 y 22±2 (pBACKGROUND: Heart failure (HF is associated with resting increased peripheral and central chemosensitivity which may correlate with an increased ventilatory response to exercise. However

  4. Application value of ATP based bioluminescence tumor chemo-sensitivity assay in the chemotherapy forhydrothorax caused by non-small cell lung cancer%肿瘤药敏指导下的化疗对非小细胞肺癌并恶性胸水治疗的有效性

    Institute of Scientific and Technical Information of China (English)

    雷开键; 林绍云; 贾钰铭; 王静; 江茂琼

    2012-01-01

    To investigate the clinical value and application of ATP based bioluminescence tumor chemo-sensitivity assay( ATP-TCA) in the chemotherapy for hydrothorax caused by non-small cell lung cancer(NSCLC) . Methods Hydrotho-rax specimens from 120 NSCLC patients were analyzed by ATP-TCA and the most sensitive chemotherapeutic drugs were used in NSCLC patients(treatment group). At the same time,56 NSCLC patients with hydrothorax were admitted in our department and were given chemotherapy without guidance of the ATP-TCA( control group) . Before the third chemotherapeutic cycle, clinical outcomes were analyzed in the two groups. Results Effective rate of hydrothorax in treatment group was 67% , while 46% in control group , P <0. 05. In refractory hydrothorax patients, it was 69% and 40% , P <0. 05, respectively. In vitro results correlated well with clinical outcomes(P <0. 01). Conclusion Effective rate of chemotherapy for hydrothorax in NSCLC is higher in treatment group than that in control group ATP-TCA is especially helpful for refractory hudrothorax.%目的 探讨ATP肿瘤药敏(ATP-TCA)指导下的化疗对非小细胞肺癌并恶性胸水治疗的有效性.方法 采用ATP-TCA检测120例非小细胞肺癌(NSCLC)患者的胸水标本,选择最敏感的化疗方案用于胸水治疗(治疗组);同期收治的56例非小细胞肺癌胸水患者,非药敏指导下的化疗(对照组).两者效果进行比较.结果 治疗组胸水治疗有效率67%,对照组46%,P<0.05.难治性胸水患者,治疗组中有效率69%,对照组40%,P<0.05.体外敏感与体内有效性之间有相关性(P<0.01).结论 ATP-TCA指导下的化疗对非小细胞肺癌并恶性胸水治疗的有效率较非药敏指导下的化疗有效率高.特别是对难治性胸水的治疗有指导价值.

  5. Lentivirus-mediated RNA interference of CD133 inhibits the proliferation of CD133+ liver cancer stem cells and increases their cisplatin chemosensitivity%RNA干扰抑制CD133表达对CD133+肝癌干细胞增殖和化疗敏感性的影响

    Institute of Scientific and Technical Information of China (English)

    兰曦; 王勇; 曹姝; 邹冬玲; 李芳; 李少林

    2012-01-01

    Objective To study the effects of CD133 suppression by lentivirus-mediated RNA interference (RNAi) on the proliferation and chemosensitivity of CD133+ cancer stem cells (CSCs) sorted from HepG2 cell line. Methods CD133+ and CD133-cells were sorted from HepG2 cell line by flow cytometry, and the expression of CD133 before and after cell sorting were detected. The stem cell property of sorted CD133+ cells were validated by sphere-forming assay in vitro and xenograft experiments in vivo. Lentivirus-mediated short haipin RNA (shRNA) targeting CD133 were transfected into CD133+ cells, and CD133 mRNA and protein expressions of the transfected cells were detected by RT-PCR and Western blotting, respectively. Before and after the transfection, the proliferative ability of CD133+ cells was evaluated by colony formation assay, and the cell growth inhibition rate and apoptosis following ciplatin exposure were detected using CCK-8 assay and flow cytometry. Results The sorted CD133+ cells showed a high purity of (88.74±3.19)%, as compared with the purity of (3.36±1.80)% before cell sorting. CD133+ cells showed a high tumor sphere formation ability and tumorigenesis capacity compared with CD133- cells. CD133 shRNA transfection significantly inhibited CD133 mRNA and protein expressions in CD133+ cells (P<0.01), resulting also in a significantly lowered cell proliferative ability (P<0.01) and an increased growth inhibition rate (P<0.01) and obviously increased cell apoptosis (P<0.05) after cisplatin exposure. Conclusions Lentivirus-mediated RNAi for CD133 suppression inhibits the proliferation of CD133+ liver cancer stem cells and increases their chemosensitivity to cisplatin.%目的 利用慢病毒介导的RNA干扰技术下调CD133+ HepG2肝癌干细胞中CD133的表达,探讨其对肝癌干细胞增殖及化疗敏感性的影响.方法 利用流式分选技术筛选CD133+ HepG2细胞并检测分选前后CD133表达量,体外成球及体内成瘤实验鉴定

  6. 热休克蛋白70反义脱氧寡核苷酸对宫颈癌HeLa细胞生长和凋亡及化学治疗敏感性的影响%Effect of heat shock protein 70 antisense oligodeoxynucleotides on growth, apoptosis and chemosensitivity for human cervical cancer HeLa cells

    Institute of Scientific and Technical Information of China (English)

    刘春梅; 丁依玲

    2013-01-01

    Objective:To explore the effect of heat shock protein 70 (HSP70) antisense oligodeoxynucleotides on proliferation, apoptosis and chemosensitivity for HeLa cells induced by cisplatin. Methods:l)HeLa cells were transfected by antisense, sense or random oligonucleotides. The cells were divided into a control group (Ctrl group, n=S), a antisense oligodeoxynucleotides treatment group (AS group, n=5), a sense oligodeoxynucleotides treatment group (S group, n=5) and a random oligonucleotides treatment group (R group, n=5). The expression of heat shock proteins 70 (HSP70) in the cells from each group was detected. 2) The HeLa cells were treated by cisplatin and were divided into a control group (control group, n=8), a cisplatin treatment group (Cis group, n=8), a antisense oligodeoxynucleotides + cisplatin treatment group (AS +Cis group, n=8), a sense oligodeoxynucleotides + cisplatin treatment group (S +Cis group, n=8) and a random oligonucleotides + cisplatin treatment group (R +Cis group, n=8). The growth inhibitory rate of HeLa cells was determined by methyl thiazolyl tetrazolium (MTT) assay. The apoptosis rate was detected by flow cytometry (FCM). Results:l)The optical density of HSP70 band in the Ctrl group, the AS group, the S group, and the Rgroup were (1.365 ±0.187) , (0.379 ±0.134), (1.403 ±0.163) and (l.410±0.158), respectively, which was significantly decreased in the AS group (P<0.0l). 2) Compared with the control group, the growth inhibitory rate and the apoptosis rate of HeLa cells were significantly increased only in AS+Cis group (P<0.05). Conclusion:HSP70 antisense oligodeoxynucleotides can effectively inhibit the proliferation of HeLa cells and induce its apoptosis through down-regulation of HSP70 expression. HSP70 antisense oligodeoxynucleotides can increase the chemosensitivity of tumor to cisplatin treatment.%目的:探讨反义脱氧寡核苷酸封闭HSP70基因对体外宫颈癌HeLa细胞增殖、凋亡及化疗敏感性的影响.方法:1)将体

  7. systems

    Directory of Open Access Journals (Sweden)

    Alexander Leonessa

    2000-01-01

    Full Text Available A nonlinear robust control-system design framework predicated on a hierarchical switching controller architecture parameterized over a set of moving nominal system equilibria is developed. Specifically, using equilibria-dependent Lyapunov functions, a hierarchical nonlinear robust control strategy is developed that robustly stabilizes a given nonlinear system over a prescribed range of system uncertainty by robustly stabilizing a collection of nonlinear controlled uncertain subsystems. The robust switching nonlinear controller architecture is designed based on a generalized (lower semicontinuous Lyapunov function obtained by minimizing a potential function over a given switching set induced by the parameterized nominal system equilibria. The proposed framework robustly stabilizes a compact positively invariant set of a given nonlinear uncertain dynamical system with structured parametric uncertainty. Finally, the efficacy of the proposed approach is demonstrated on a jet engine propulsion control problem with uncertain pressure-flow map data.

  8. PIG7 promotes leukemia cell chemosensitivity via lysosomal membrane permeabilization.

    Science.gov (United States)

    Liu, Jiazhuo; Peng, Leiwen; Niu, Ting; Wu, Yu; Li, Jianjun; Wang, Fangfang; Zheng, Yuhuan; Liu, Ting

    2016-01-26

    PIG7 localizes to lysosomal membrane in leukemia cells. Our previous work has shown that transduction of pig7 into a series of leukemia cell lines did not result in either apoptosis or differentiation of most tested cell lines. Interestingly, it did significantly sensitize these cell lines to chemotherapeutic drugs. Here, we further investigated the mechanism underlying pig7-induced improved sensitivity of acute leukemia cells to chemotherapy. Our results demonstrated that the sensitization effect driven by exogenous pig7 was more effective in drug-resistant leukemia cell lines which had lower endogenous pig7 expression. Overexpression of pig7 did not directly activate the caspase apoptotic pathway, but decreased the lysosomal stability. The expression of pig7 resulted in lysosomal membrane permeabilization (LMP) and lysosomal protease (e.g. cathepsin B, D, L) release. Moreover, we also observed increased reactive oxygen species (ROS) and decreased mitochondrial membrane potential (ΔΨm) induced by pig7. Some autophagy markers such as LC3I/II, ATG5 and Beclin-1, and necroptosis maker MLKL were also stimulated. However, intrinsic antagonism such as serine/cysteine protease inhibitors Spi2A and Cystatin C prevented downstream effectors from triggering leukemia cells, which were only on the "verge of apoptosis". When combined with chemotherapy, LMP increased and more proteases were released. Once this process was beyond the limit of intrinsic antagonism, it induced programmed cell death cooperatively via caspase-independent and caspase-dependent pathways.

  9. 脂质体介导Clusterin反义寡核苷酸抑制胰腺癌细胞侵袭力及增强5—FU化疗敏感性的实验研究%Liposome-mediated clusterin antisense oligodeoxynucleotides inhibit invasion and chemosensitize 5-FU.in human pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    迟绍云; 焦学龙; 王宝泉; 刘春生; 王蕾; 贾旭亮; 牛珉

    2012-01-01

    目的 研究Clusterin反义寡聚脱氧核苷酸(Clusterin ASO)对胰腺癌细胞侵袭力及5-FU化疗敏感性的影响.方法 采用脂质体法将Clusterin ASO转染PANC-1细胞24 h,然后将该细胞暴露于不同浓度的5-FU中,TUNEL法检测72 h后的细胞凋亡指数,MTT检测细胞增殖并计算IC50.观察Clusterin ASO转染对PANC-1细胞体外侵袭力的抑制作用.采用免疫组化,Western blot和RT-PCR技术检测不同处理组细胞中Clusterin和其mRNA和蛋白表达.结果 Clusterin ASO转染可有效沉默PANC-1细胞内Clusterin mRNA及蛋白表达;PANC-1细胞的5-FU IC50为9±0.7,PANC-1/Clusterin ASO的5-FU IC50为1.06±0.3,敏感性增加了9倍.5-FU以剂量依赖方式诱导PANC-1细胞凋亡,但对PANC-1/Clusterin ASO细胞所诱导的凋亡比PANC-1细胞更明显.重组细胞基膜侵袭实验显示,PANC-1细胞与PANC-1/Clusterin ASO细胞的穿透基膜细胞数分别为213±18个和43±8个/高倍镜(×200),差异有统计学意义(P<0.05).结论 靶向Clusterin抑制胰腺癌细胞侵袭力和增殖,并增强胰腺癌细胞对5-FU的化疗敏感性.%Purpose To investigate whether clusterin gene silencing by antisense clusterin oligodeoxynucleotides ( ASO ) can inhibit invasion and metastasis and chemosensitize 5-FU in human pancreatic cancer cell line PNAC-1. Methods Clusterin ASO was transfected into PANC-1 cells for 24 h by Lipofectamine 2000 methods, and then the cells in different groups were treated with serial concentrations ( 0. 01 ~ 100 μmol/L ) of 5-FU for 72 h. The 50% inhibitory drug concentration ( IC50 ) was obtained by MTT assay. The apoptosis was assessed by TUNEL staining. The inhibitory effects of clusterin ASO on invasion and metastasis were detected by Transwell motility assay. RT-PCR and Western blot were used to detect the clusterin protein and mRNA in PANC-1 cells in vitro. Results Clusterin expression was inhibited in PANC-1 cells in clusterin ASO groups. The inhibitory effect of cell growth was seen

  10. SYSTEM

    Directory of Open Access Journals (Sweden)

    K. Swarnalatha

    2013-01-01

    Full Text Available Risk analysis of urban aquatic systems due to heavy metals turns significant due to their peculiar properties viz. persis tence, non-degradab ility, toxicity, and accumulation. Akkulam Veli (AV, an urba n tropical lake in south India is subjected to various environmental stresses due to multiple waste discharge, sand mining, developmental activities, tour ism related activitie s etc. Hence, a comprehensive approach is adopted for risk assessment using modified degree of contamination factor, toxicity units based on numerical sediment quality guidelines (SQGs, and potentialecological risk indices. The study revealed the presence of toxic metals such as Cr, C d, Pb and As and the lake is rated under ‘low ecological risk’ category.

  11. A Meta Analysis of (β-Tubulin Ⅲ and Chemosensitivity to Anti-Microtubule Agents in Patients with Advanced Non-Small Cell Lung Cancer%晚期非小细胞肺癌β-微管蛋白Ⅲ表达与抗微管药敏感性Meta分析

    Institute of Scientific and Technical Information of China (English)

    沈红; 蔡健康; 沈立; 崔进; 王虹

    2011-01-01

    Objective The aim of this study is to determine the relationship between expression of β-tubulin Ⅲ and chemosensitivity to anti-mierotubule agents in patients with advanced non-small cell lung cancer (NSCLC).Methods The method of meta-analysis was applied to analyze the data reported in relevant literatures.Results Five English and three Chinese settings with 457 patients were selected.In the subgroup receiving Taxane, the numbers of patients with low-expression were 112, and the response rate was 50.9%.Patients with high expression were 101,and the response rate was 18.8%.The combined odds ratio (OR) was 4.75, with 95% confidence interval of 2.53~8.92, P<0.000 01.In the subgroup receiving vinorelbine, the numbers of low-expression were 89, and the response rate was 39.3%.Patients with high expression were 102, and the response rate was 26.5%.The combined OR was 1.75 with 95% confidence interval of 0.95~3.22, P=0.07.In the subgroup randomly receiving taxane or vinorelbine, the numbers of low-expression were 22, the response rate was 54.5%.Patients with high expression were 31, and the response rate was 29%.The OR was 2.93 with 95% confidence interval of 0.94~9.20, P=0.06.Conclusion A high level of β-tubulin Ⅲ is associated with resistance to anti-microtubule agents especially taxane in advanced NSCLC patients, This finding can provide information critical to personalized chemotherapy.%目的 探讨晚期非小细胞肺癌患者卜微管蛋白m表达与抗微管化疗药敏感性的关系.方法应用Meta分析对晚期非小细胞肺癌患者β-微管蛋白Ⅲ表达与抗微管类化疗药有效性的文献进行综合定量评价.结果 入选5篇英文和3篇中文文献,共457例.在紫杉类治疗患者中,β-微管蛋白Ⅲ低表达和高表达分别为112例和101例,有效率分别为50.9%和18.8%,合并优势比为4.75,95%可信区间2.53~8.92,P<0.00001.在长春瑞滨组,β-微管蛋白Ⅲ低表达和高表达分别为89

  12. 5-氮杂胞苷调控TIP30基因表达对人结直肠癌细胞氟尿嘧啶敏感性的影响%Effects of 5-Aza-dC on 5-Fu chemosensitivity by modulating TIP30 gene expression in human colorectal cancer cells

    Institute of Scientific and Technical Information of China (English)

    陈小兵; 陈贝贝; 李剑; 王新锋; 马一杰; 罗素霞; 吕慧芳

    2013-01-01

    目的 探讨5-氮杂胞苷(5-Aza-dC)对结直肠癌细胞中TIP30基因表达的影响,并探讨其与氟尿嘧啶(5-Fu)敏感性的关系.方法 5-Aza-dC处理结直肠癌HCT116细胞,采用甲基化特异性PCR (MSP)方法检测TIP30基因启动子CpG岛甲基化状态,逆转录PCR检测TIP30 mRNA表达,Western blot法检测TIP30蛋白的表达,四甲基偶氮唑蓝(MTT)法检测HCT116细胞对5-Fu的敏感性.结果 未经5-Aza-dC处理的HCT116细胞中,TIP30基因启动子完全甲基化.5-Aza-dC处理HCT116细胞3d后去除5-Aza-dC,HCT116细胞TIP30基因非甲基化产物阳性,启动子去甲基化.随着5-Aza-dC去除时间的延长,HCT116细胞中TIP30基因启动子甲基化产物和非甲基化产物均为阳性,即启动子部分甲基化,部分非甲基化;去除5-Aza-dC第10天,TIP30基因启动子甲基化产物阳性,TIP30基因启动子重新甲基化.未经5-Aza-dC处理的结直肠癌HCT116细胞TIP30 mRNA和蛋白不表达.5-Aza-dC处理结直肠癌HCT116细胞3d后去除5-Aza-dC,TIP30 mRNA和蛋白表达明显增强.随着5-Aza-dC去除时间的延长,TIP30 mRNA和蛋白表达水平逐渐降低,第10天达到最低水平.在5-Aza-dC处理前、5-Aza-dC处理后去除5-Aza-dC的第0、10天,5-Fu作用于HCT116细胞的半数抑制浓度(IC50)分别为41.62、33.17和4.96 μg/ml.结论 TIP30基因表达差异可能与其启动子甲基化状态有关,且TIP30基因启动子甲基化差异与结直肠癌细胞对化疗药物的敏感性相关.%Objective To investigate the effect of 5-Aza-2'-deoxycytidine (5-Aza-dC) on TIP30 gene expression and the relationship between TIP30 expression and the sensitivity to 5-fluouracil (5-Fu) in colorectal cancer cells.Methods The methylation profile of TIP30 gene in HCT116 colorectal cancer cells was determined by methylation-specific PCR.The levels of TIP30 mRNA and protein were determined by RT-PCR and Western blot after the 5-Aza-dC treatment.MTT assay was used to detect the chemosensitivity of HCT116

  13. Hybrid liposomal PEGylated calix[4]arene systems as drug delivery platforms for curcumin.

    Science.gov (United States)

    Drakalska, Elena; Momekova, Denitsa; Manolova, Yana; Budurova, Dessislava; Momekov, Georgi; Genova, Margarita; Antonov, Liudmil; Lambov, Nikolay; Rangelov, Stanislav

    2014-09-10

    The tremendous therapeutic potential of curcumin as a chemopreventive, antineoplastic and chemosensitizing agent has failed to progress towards clinical development and commercialization due to its unfavorable physicochemical properties, low aqueous solubility, chemical instability, and pharmacokinetics. The present contribution is focused on the feasibility of using PEGylated calixarene, in particular polyoxyethylene-derivatized tert-butylcalix[4]arene, to prepare various platforms for delivery of curcumin such as inclusion complex, supramolecular aggregates, and hybrid liposomal systems. The inclusion complex is characterized by UV-vis and FT-IR spectroscopy as well as thermal gravimetrical analysis and differential scanning calorimetry. At concentrations exceeding the critical micellization concentration of PEGylated calixarene, the tremendous solubility enhancement of curcumin is attributed to additional solubilization and hydrophobic non-covalent interactions of the drug with supramolecular aggregates. A hybrid liposomal system is created via encapsulation of the inclusion complex in dipalmitoylphosphatidylcholine:cholesterol liposomes. Bare and liposomal curcumin:BEC-X inclusion complexes, as well as free curcumin were additionally investigated for cytotoxicity and apoptogenic activity against human tumor cell lines.

  14. Facilitation of breathing by leptin effects in the central nervous system.

    Science.gov (United States)

    Bassi, M; Furuya, W I; Zoccal, D B; Menani, J V; Colombari, D S A; Mulkey, D K; Colombari, E

    2016-03-15

    With the global epidemic of obesity, breathing disorders associated with excess body weight have markedly increased. Respiratory dysfunctions caused by obesity were originally attributed to mechanical factors; however, recent studies have suggested a pathophysiological component that involves the central nervous system (CNS) and hormones such as leptin produced by adipocytes as well as other cells. Leptin is suggested to stimulate breathing and leptin deficiency causes an impairment of the chemoreflex, which can be reverted by leptin therapy. This facilitation of the chemoreflex may depend on the action of leptin in the hindbrain areas involved in the respiratory control such as the nucleus of the solitary tract (NTS), a site that receives chemosensory afferents, and the ventral surface of the medulla that includes the retrotrapezoid nucleus (RTN), a central chemosensitive area, and the rostral ventrolateral medulla (RVLM). Although the mechanisms and pathways activated by leptin to facilitate breathing are still not completely clear, evidence suggests that the facilitatory effects of leptin on breathing require the brain melanocortin system, including the POMC-MC4R pathway, a mechanism also activated by leptin to modulate blood pressure. The results of all the studies that have investigated the effect of leptin on breathing suggest that disruption of leptin signalling as caused by obesity-induced reduction of central leptin function (leptin resistance) is a relevant mechanism that may contribute to respiratory dysfunctions associated with obesity.

  15. [Mathematical simulation of the respiratory system (author's transl)].

    Science.gov (United States)

    Middendorf, T; Loeschcke, H H

    1976-06-30

    The respiratory system is described as a feedback control system. The controller consists of the peripheral chemoreceptors and the central chemosensitive structures, the respiratory centre in the medulla oblongata and the thorax-lung pump which they drive. The controlled system is comprised of three compartments (lung, brain and the remaining tissue) connected by the blood circulation. The controlled values are arterial pH and arterial O2 partial pressure and cerebral extracellular pH. Earlier models have been improved by: (1) the dead space description, (2) the thermodynamic formulation of the CO2 dissociation equation and the simple but accurate O2 dissociation equation of the blood, (3) the alteration of the CO2 dissociation equation for the brain and the remaining tissue to accommodate recent results, (4) the application of the one-receptor-theory of central chemosensitivity, (5) the pH dependence of brain circulation, (6) the bicarbonate exchange between blood and extracellular fluid of the brain and (7) the introduction of variable circulation times. Respiratory and metabolic disturbances of the respiratory system are analyzed. The mathematical formulation of the respiratory system is a differential difference equation system. In the steady state the experimental results are reproduced fairly well. A slight discrepancy is found in the simulation of metabolic acidosis. Apparently we have assumed the sensitivity of the peripheral chemoreceptors to be too large so that the respiratory response is not correctly predicted. In the numerical solution there is an overshoot in the on-transient and a damped oscillation in the off-transient of the alveolar CO2 partial pressure during respiratory acidosis. We have varied the parameters to make deviations small. The best agreement seems to result, if the central threshold is near the normal extracellular pH of the brain. A further deviation from experimental findings is that the cerebral CO2 and H+ concentration, the

  16. Low levels of graphene and graphene oxide inhibit cellular xenobiotic defense system mediated by efflux transporters.

    Science.gov (United States)

    Liu, Su; Jiang, Wei; Wu, Bing; Yu, Jing; Yu, Haiyan; Zhang, Xu-Xiang; Torres-Duarte, Cristina; Cherr, Gary N

    2016-01-01

    Low levels of graphene and graphene oxide (GO) are considered to be environmentally safe. In this study, we analyzed the potential effects of graphene and GO at relatively low concentrations on cellular xenobiotic defense system mediated by efflux transporters. The results showed that graphene (graphene and GO at the nontoxic concentrations could increase calcein-AM (CAM, an indicator of membrane ATP-binding cassette (ABC) transporter) activity) accumulation, indicating inhibition of ABC transporters' efflux capabilities. This inhibition was observed even at 0.005 μg/mL graphene and 0.05 μg/mL GO, which are 100 times and 400 times lower than their lowest toxic concentration from cytotoxicity experiments, respectively. The inhibition of ABC transporters significantly increased the toxicity of paraquat and arsenic, known substrates of ABC transporters. The inhibition of ABC transporters was found to be based on graphene and GO damaging the plasma membrane structure and fluidity, thus altering functions of transmembrane ABC transporters. This study demonstrates that low levels of graphene and GO are not environmentally safe since they can significantly make cell more susceptible to other xenobiotics, and this chemosensitizing activity should be considered in the risk assessment of graphene and GO.

  17. Naloxone application to the ventrolateral medulla enhances the respiratory response to inspired carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Trouth, C.O.; Bada, F.J.; Pan, Yi; Holloway, J.A.; Millis, R.M.; Bernard, D.G. (Howard Univ., Washington, D.C. (USA))

    1991-01-01

    Previous studies have shown that systemic administration of the opiate antagonist naloxone potentiates the ventilatory response to inspired carbon dioxide. The present study was designed to localize the site of action of naloxone for increasing the respiratory chemosensitivity to inhaled carbon dioxide (CO{sub 2}) in cats. Naloxone applied topically to the caudal chemosensitive area on the ventral medullary surface (VMS) during hypercapnic breathing produced a 75% greater increase in minute ventilation than hypercapnic breathing alone. Furthermore, hypercapnic breathing produced a 200% increase in neuronal activity of VMS chemosensitive cells; this was further increased 120% by naloxone. It is concluded that naloxone increases the sensitivity of neurons in the caudal respiratory chemosensitive area of cats to hypercapnia, and that endogenous opiates may act as modulators at VMS chemosensitive sites during hypercapnic breathing.

  18. System xc⁻ cystine/glutamate antiporter: an update on molecular pharmacology and roles within the CNS.

    Science.gov (United States)

    Bridges, Richard J; Natale, Nicholas R; Patel, Sarjubhai A

    2012-01-01

    System x(c)(-) is an amino acid antiporter that typically mediates the exchange of extracellular l-cystine and intracellular L-glutamate across the cellular plasma membrane. Studied in a variety of cell types, the import of L-cystine through this transporter is critical to glutathione production and oxidative protection. The exchange-mediated export of L-glutamate takes on added significance within the CNS, as it represents a non-vesicular route of release through which this excitatory neurotransmitter can participate in either neuronal signalling or excitotoxic pathology. When both the import of L-cystine and the export of L-glutamate are taken into consideration, system x(c)(-) has now been linked to a wide range of CNS functions, including oxidative protection, the operation of the blood-brain barrier, neurotransmitter release, synaptic organization, viral pathology, drug addiction, chemosensitivity and chemoresistance, and brain tumour growth. The ability to selectively manipulate system x(c)(-), delineate its function, probe its structure and evaluate it as a therapeutic target is closely linked to understanding its pharmacology and the subsequent development of selective inhibitors and substrates. Towards that goal, this review will examine the current status of our understanding of system x(c)(-) pharmacology and the structure-activity relationships that have guided the development of an initial pharmacophore model, including the presence of lipophilic domains adjacent to the substrate binding site. A special emphasis is placed on the roles of system x(c)(-) within the CNS, as it is these actions that are among the most exciting as potential long-range therapeutic targets.

  19. Arctigenin enhances chemosensitivity of cancer cells to cisplatin through inhibition of the STAT3 signaling pathway.

    Science.gov (United States)

    Yao, Xiangyang; Zhu, Fenfen; Zhao, Zhihui; Liu, Chang; Luo, Lan; Yin, Zhimin

    2011-10-01

    Arctigenin is a dibenzylbutyrolactone lignan isolated from Bardanae fructus, Arctium lappa L, Saussureamedusa, Torreya nucifera, and Ipomea cairica. It has been reported to exhibit anti-inflammatory activities, which is mainly mediated through its inhibitory effect on nuclear transcription factor-kappaB (NF-κB). But the role of arctigenin in JAK-STAT3 signaling pathways is still unclear. In present study, we investigated the effect of arctigenin on signal transducer and activator of transcription 3 (STAT3) pathway and evaluated whether suppression of STAT3 activity by arctigenin could sensitize cancer cells to a chemotherapeutic drug cisplatin. Our results show that arctigenin significantly suppressed both constitutively activated and IL-6-induced STAT3 phosphorylation and subsequent nuclear translocation in cancer cells. Inhibition of STAT3 tyrosine phosphorylation was found to be achieved through suppression of Src, JAK1, and JAK2, while suppression of STAT3 serine phosphorylation was mediated by inhibition of ERK activation. Pervanadate reversed the arctigenin-induced downregulation of STAT3 activation, suggesting the involvement of a protein tyrosine phosphatase. Indeed, arctigenin can obviously induce the expression of the PTP SHP-2. Furthermore, the constitutive activation level of STAT3 was found to be correlated to the resistance of cancer cells to cisplatin-induced apoptosis. Arctigenin dramatically promoted cisplatin-induced cell death in cancer cells, indicating that arctigenin enhanced the sensitivity of cancer cells to cisplatin mainly via STAT3 suppression. These observations suggest a novel anticancer function of arctigenin and a potential therapeutic strategy of using arctigenin in combination with chemotherapeutic agents for cancer treatment.

  20. Clinical Impact of a Novel MicroRNA Chemo-Sensitivity Predictor in Gastrooesophageal Cancer

    DEFF Research Database (Denmark)

    Winther, Mette; Knudsen, Steen; Dahlgaard, Jesper;

    2016-01-01

    survival (OS) and disease-specific survival (DSS). MATERIAL AND METHODS: The study population encompassed 53 patients treated with curative intend for loco-regional gastrooesophageal cancer. miRNA expression was quantified from pre-therapeutic and diagnostic, formalin-fixed, paraffin embedded tumour...

  1. Progesterone receptor membrane component 1 deficiency attenuates growth while promoting chemosensitivity of human endometrial xenograft tumors

    NARCIS (Netherlands)

    A.M. Friel (Anne M.); L. Zhang (Ling); C.A. Pru (Cindy A.); N.C. Clark (Nicole C.); M.L. McCallum (Melissa L.); L.J. Blok (Leen); T. Shioda (Toshi); J.J. Peluso (John J.); B.R. Rueda (Bo R.); J.K. Pru (James K.)

    2015-01-01

    textabstractEndometrial cancer is the leading gynecologic cancer in women in the United States with 52,630 women predicted to be diagnosed with the disease in 2014. The objective of this study was to determine if progesterone (P4) receptor membrane component 1 (PGRMC1) influenced endometrial cancer

  2. Chemosensitizing and cytotoxic effects of 2-deoxy-D-glucose on breast cancer cells

    Directory of Open Access Journals (Sweden)

    Zhang Fanjie

    2009-09-01

    Full Text Available Background: Accelerated glucose uptake for anerobic glycolysis is one of the major metabolic changes found in malignant cells. This property has been exploited for imaging malignancies and as a possible anticancer therapy. The nonmetabolizable glucose analog 2-deoxyglucose (2 DG interferes with glucose metabolism leading to breast cancer cell death. Aims: To determine whether 2DG can synergize with chemotherapeutic agents commonly used in breast cancer treatment and identify cellular characteristics associated with sensitivity to 2DG. Materials and Methods: SkBr3 breast cancer cells were incubated with varying concentrations of 5-fluorouracil (5FU, doxorubicin, cisplatin, cyclophosphamide, or herceptin with or without 2DG. Cell viability was measured using the MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Results: Combining 2DG with doxorubicin, 5 FU, cyclophosphamide, and herceptin resulted in enhanced cell death compared with each agent alone, while in combination with cisplatin, the amount of cell death was additive. Mouse embryo fibroblasts (MEF mutated for p53 (-/- were 30% more sensitive to the cytotoxic effects of 2DG than the parental cell lines. Cells mutated for Bax/Bac, genes involved in protection from apoptosis, are slightly more sensitive than the parental cell lines. Conclusions: These results indicate that 2DG acts synergistically with specific chemotherapeutic agents in causing cell death and the class of chemicals most sensitive appear to be those which cause DNA damage.

  3. A single gene target of an ETS-family transcription factor determines neuronal CO2-chemosensitivity.

    Directory of Open Access Journals (Sweden)

    Julia P Brandt

    Full Text Available Many animals possess neurons specialized for the detection of carbon dioxide (CO(2, which acts as a cue to elicit behavioral responses and is also an internally generated product of respiration that regulates animal physiology. In many organisms how such neurons detect CO(2 is poorly understood. We report here a mechanism that endows C. elegans neurons with the ability to detect CO(2. The ETS-5 transcription factor is necessary for the specification of CO(2-sensing BAG neurons. Expression of a single ETS-5 target gene, gcy-9, which encodes a receptor-type guanylate cyclase, is sufficient to bypass a requirement for ets-5 in CO(2-detection and transforms neurons into CO(2-sensing neurons. Because ETS-5 and GCY-9 are members of gene families that are conserved between nematodes and vertebrates, a similar mechanism might act in the specification of CO(2-sensing neurons in other phyla.

  4. The Role of Mitochondrial TCA Cycle Enzymes in Determining Prostate Cancer Chemosensitivity

    Science.gov (United States)

    2014-03-01

    273, 4928-4936. 10. Wang, T. H., Popp, D. M., Wang, H. S., Saitoh, M., Mural , J. G., Henley, D. C., Ichijo, H., and Wimalasena, J. (1999...1/2 pathway. Clin Cancer Res 2007;13(4):1308–1314. 34. Wang TH, Popp DM, Wang HS, Saitoh M, Mural JG, Henley DC, Ichijo H, Wimalasena J. Microtubule

  5. Growth Factor Receptors and Apoptosis Regulators: Signaling Pathways, Prognosis, Chemosensitivity and Treatment Outcomes of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Siddik Sarkar

    2009-01-01

    Full Text Available Biomarkers of breast cancer are necessary for prognosis and prediction to chemotherapy. Prognostic biomarkers provide information regarding outcome irrespective of therapy, while predictive biomarkers provide information regarding response to therapy. Candidate prognostic biomarkers for breast cancers are growth factor receptors, steroid receptors, Ki-67, cyclins, urokinase plasminogen activator, p53, p21, pro- and anti-apoptotic factors, BRCA1 and BRCA2. But currently, the predictive markers are Estrogen and Progesterone receptors responding to endocrine therapy, and HER-2 responding to herceptin. But there are numerous breast cancer cases, where tamoxifen is ineffective even after estrogen receptor positivity. This lead to search of new prognostic and predictive markers and the number of potential markers is constantly increasing due to proteomics and genomics studies. However, most biomarkers individually have poor sensitivity or specificity, or other clinical value. It can be resolved by studying various biomarkers simultaneously, which will help in better prognosis and increasing sensitivity for chemotherapeutic agents. This review is focusing on growth factor receptors, apoptosis markers, signaling cascades, and their correlation with other associated biomarkers in breast cancers. As our knowledge regarding molecular biomarkers for breast cancer increases, prognostic indices will be developed that combine the predictive power of individual molecular biomarkers with specific clinical and pathologic factors. Rigorous comparison of these existing as well as emerging markers with current treatment selection is likely to see an escalation in an era of personalized medicines to ensure the breast cancer patients receive optimal treatment. This will also solve the treatment modalities and complications related to chemotherapeutic regimens.

  6. MT 2A Phosphorylation by PKC Mu/PKD Influences Chemosensitivity to Cisplatin in Prostate Cancer

    Science.gov (United States)

    2008-11-01

    which were highly expressed Tables I and II). We have established that treat- ent of PCa with zinc is an excellent in vitro modelo study the effects of...ated the in vivo conditions of a high zinc concen- ration, the caveat is that zinc concentrations ithin the heterogenous population of cells in the...protein kinase D1 n vitro and in vivo .17 The activity of protein kinase 1 can be altered by drugs such as bryostatin-1, hich may influence the function

  7. Temporal characteristics of gustatory responses in rat parabrachial neurons vary by stimulus and chemosensitive neuron type.

    Science.gov (United States)

    Geran, Laura; Travers, Susan

    2013-01-01

    It has been demonstrated that temporal features of spike trains can increase the amount of information available for gustatory processing. However, the nature of these temporal characteristics and their relationship to different taste qualities and neuron types are not well-defined. The present study analyzed the time course of taste responses from parabrachial (PBN) neurons elicited by multiple applications of "sweet" (sucrose), "salty" (NaCl), "sour" (citric acid), and "bitter" (quinine and cycloheximide) stimuli in an acute preparation. Time course varied significantly by taste stimulus and best-stimulus classification. Across neurons, the ensemble code for the three electrolytes was similar initially but quinine diverged from NaCl and acid during the second 500 ms of stimulation and all four qualities became distinct just after 1s. This temporal evolution was reflected in significantly broader tuning during the initial response. Metric space analyses of quality discrimination by individual neurons showed that increases in information (H) afforded by temporal factors was usually explained by differences in rate envelope, which had a greater impact during the initial 2s (22.5% increase in H) compared to the later response (9.5%). Moreover, timing had a differential impact according to cell type, with between-quality discrimination in neurons activated maximally by NaCl or citric acid most affected. Timing was also found to dramatically improve within-quality discrimination (80% increase in H) in neurons that responded optimally to bitter stimuli (B-best). Spikes from B-best neurons were also more likely to occur in bursts. These findings suggest that among PBN taste neurons, time-dependent increases in mutual information can arise from stimulus- and neuron-specific differences in response envelope during the initial dynamic period. A stable rate code predominates in later epochs.

  8. Ubiquitin C-terminal hydrolase-L1 potentiates cancer chemosensitivity by stabilizing NOXA.

    Science.gov (United States)

    Brinkmann, Kerstin; Zigrino, Paola; Witt, Axel; Schell, Michael; Ackermann, Leena; Broxtermann, Pia; Schüll, Stephan; Andree, Maria; Coutelle, Oliver; Yazdanpanah, Benjamin; Seeger, Jens Michael; Klubertz, Daniela; Drebber, Uta; Hacker, Ulrich T; Krönke, Martin; Mauch, Cornelia; Hoppe, Thorsten; Kashkar, Hamid

    2013-03-28

    The BH3-only protein NOXA represents one of the critical mediators of DNA-damage-induced cell death. In particular, its involvement in cellular responses to cancer chemotherapy is increasingly evident. Here, we identify a strategy of cancer cells to escape genotoxic chemotherapy by increasing proteasomal degradation of NOXA. We show that the deubiquitylating enzyme UCH-L1 is a key regulator of NOXA turnover, which protects NOXA from proteasomal degradation by removing Lys(48)-linked polyubiquitin chains. In the majority of tumors from patients with melanoma or colorectal cancer suffering from high rates of chemoresistance, NOXA fails to accumulate because UCH-L1 expression is epigenetically silenced. Whereas UCH-L1/NOXA-positive tumor samples exhibit increased sensitivity to genotoxic chemotherapy, downregulation of UCH-L1 or inhibition of its deubiquitylase activity resulted in reduced NOXA stability and resistance to genotoxic chemotherapy in both human and C. elegans cells. Our data identify the UCH-L1/NOXA interaction as a therapeutic target for overcoming cancer chemoresistance.

  9. High-dose parenteral ascorbate enhanced chemosensitivity of ovarian cancer and reduced toxicity of chemotherapy.

    Science.gov (United States)

    Ma, Yan; Chapman, Julia; Levine, Mark; Polireddy, Kishore; Drisko, Jeanne; Chen, Qi

    2014-02-05

    Ascorbate (vitamin C) was an early, unorthodox therapy for cancer, with an outstanding safety profile and anecdotal clinical benefit. Because oral ascorbate was ineffective in two cancer clinical trials, ascorbate was abandoned by conventional oncology but continued to be used in complementary and alternative medicine. Recent studies provide rationale for reexamining ascorbate treatment. Because of marked pharmacokinetic differences, intravenous, but not oral, ascorbate produces millimolar concentrations both in blood and in tissues, killing cancer cells without harming normal tissues. In the interstitial fluid surrounding tumor cells, millimolar concentrations of ascorbate exert local pro-oxidant effects by mediating hydrogen peroxide (H(2)O(2)) formation, which kills cancer cells. We investigated downstream mechanisms of ascorbate-induced cell death. Data show that millimolar ascorbate, acting as a pro-oxidant, induced DNA damage and depleted cellular adenosine triphosphate (ATP), activated the ataxia telangiectasia mutated (ATM)/adenosine monophosphate-activated protein kinase (AMPK) pathway, and resulted in mammalian target of rapamycin (mTOR) inhibition and death in ovarian cancer cells. The combination of parenteral ascorbate with the conventional chemotherapeutic agents carboplatin and paclitaxel synergistically inhibited ovarian cancer in mouse models and reduced chemotherapy-associated toxicity in patients with ovarian cancer. On the basis of its potential benefit and minimal toxicity, examination of intravenous ascorbate in combination with standard chemotherapy is justified in larger clinical trials.

  10. CIAPIN1 gene silencing enhances chemosensitivity in a drug-resistant animal model in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.M.; Gao, S.J.; Guo, X.F.; Sun, W.J. [Department of Oncology, The Second Affiliated Hospital, Harbin Medical University, Harbin (China); Yan, Z.Q. [Department of Breast Surgery, The Second Affiliated Hospital, Harbin Medical University, Harbin (China); Wang, W.X.; Xu, Y.Q.; Lu, D. [Department of Oncology, The Second Affiliated Hospital, Harbin Medical University, Harbin (China)

    2014-03-21

    Overexpression of cytokine-induced apoptosis inhibitor 1 (CIAPIN1) contributes to multidrug resistance (MDR) in breast cancer. This study aimed to evaluate the potential of CIAPIN1 gene silencing by RNA interference (RNAi) as a treatment for drug-resistant breast cancer and to investigate the effect of CIAPIN1 on the drug resistance of breast cancer in vivo. We used lentivirus-vector-based RNAi to knock down CIAPIN1 in nude mice bearing MDR breast cancer tumors and found that lentivirus-vector-mediated silencing of CIAPIN1 could efficiently and significantly inhibit tumor growth when combined with chemotherapy in vivo. Furthermore, Western blot analysis showed that both CIAPIN1 and P-glycoprotein expression were efficiently downregulated, and P53 was upregulated, after RNAi. Therefore, we concluded that lentivirus-vector-mediated RNAi targeting of CIAPIN1 is a potential approach to reverse MDR of breast cancer. In addition, CIAPIN1 may participate in MDR of breast cancer by regulating P-glycoprotein and P53 expression.

  11. miRNAs associated with chemo-sensitivity in cell lines and in advanced bladder cancer

    DEFF Research Database (Denmark)

    Nordentoft, Iver; Birkenkamp-Demtroder, Karin; Agerbæk, Mads;

    2012-01-01

    Background MicroRNA is a naturally occurring class of non-coding RNA molecules that mediate posttranscriptional gene regulation and are strongly implicated in cellular processes such as cell proliferation, carcinogenesis, cell survival and apoptosis. Consequently there is increasing focus on mi......RNA expression as prognostic factors for outcome and chemotherapy response. Only approximately 50% of patients with bladder cancer respond to chemotherapy. Therefore, predictive markers, such as miRNAs, that can identify subgroups of patients who will benefit from chemotherapy will have great value for treatment...... with progressive disease and in tumors form patients with short and long overall survival time. Furthermore, we studied the effect of up- and down regulation of key miRNAs on the cisplatin sensitivity in eight bladder cancer cell lines with different sensitivities to cisplatin. Results miRNA expression profiling...

  12. A Serial Analysis of Gene Expression (SAGE) database analysis of chemosensitivity

    DEFF Research Database (Denmark)

    Stein, Wilfred D; Litman, Thomas; Fojo, Tito;

    2004-01-01

    with expression of cell adhesion, cytoskeletal, and ECM genes, a pattern similar to that found to distinguish solid tumors from the more cytotoxin-sensitive cancer cell lines. One interpretation is that resistance to chemotherapy may arise, in part, from the adherent, relatively inert condition (i.e., low...

  13. Chemosensitivity profile assay of circulating cancer cells: prognostic and predictive value in epithelial tumors.

    Science.gov (United States)

    Gazzaniga, Paola; Naso, Giuseppe; Gradilone, Angela; Cortesi, Enrico; Gandini, Orietta; Gianni, Walter; Fabbri, Maria Agnese; Vincenzi, Bruno; di Silverio, Franco; Frati, Luigi; Aglianò, Anna Maria; Cristofanilli, Massimo

    2010-05-15

    The prognostic value associated with the detection of circulating tumor cells (CTCs) in metastatic breast cancer by the CellSearch technology raise additional issues regarding the biological value of this information. We postulated that a drug-resistance profile of CTCs may predict response to chemotherapy in cancer patients and therefore could be used for patient selection. One hundred 5 patients with diagnosis of carcinoma were enrolled in a prospective trial. CTCs were isolated from peripheral blood, and positive samples were evaluated for the expression of a panel of genes involved in anticancer drugs resistance. The drug-resistance profile was correlated with disease-free survival (DFS; patients in adjuvant setting) and time to progression (TTP; metastatic patients) in a 24-months follow-up. Objective response correlation was a secondary end point. Fifty-one percent of patients were found positive for CTCs while all blood samples from healthy donors were negative. The drug-resistance profile correlates with DFS and TTP (p < 0.001 in both). Sensitivity of the test: able to predict treatment response in 98% of patients. Specificity of the test: 100%; no sample from healthy subject was positive for the presence of CTCs. Positive and negative predictive values were found to be 96.5 and 100%, respectively. We identified a drug-resistance profile of CTCs, which is predictive of response to chemotherapy, independent of tumor type and stage of disease. This approach may represent a first step toward the individualization of chemotherapy in cancer patients.

  14. A complex mechanism for HDGF-mediated cell growth, migration, invasion, and TMZ chemosensitivity in glioma.

    Science.gov (United States)

    Song, Ye; Hu, Zheng; Long, Hao; Peng, Yuping; Zhang, Xi'an; Que, Tianshi; Zheng, Shihao; Li, Zhiyong; Wang, Gang; Yi, Liu; Liu, Zhen; Fang, Weiyi; Qi, Songtao

    2014-09-01

    HDGF is overexpressed in gliomas as compared to normal brain. We therefore analyzed the molecular mechanisms of HDGF action in gliomas. HDGF was downregulated in normal brain tissue as compared to glioma specimens at both the mRNA and the protein levels. In glioma samples, increased HDGF expression was associated with disease progression. Knocking down HDGF expression not only significantly decreased cellular proliferation, migration, invasion, and tumorigenesis, but also markedly enhanced TMZ-induced cytotoxicity and apoptosis in glioma cells. Mechanistic analyses revealed that CCND1, c-myc, and TGF-β were downregulated after stable HDGF knockdown in the U251 and U87 glioma cells. HDGF knockdown restored E-cadherin expression and suppressed mesenchymal cell markers such as vimentin, β-catenin, and N-cadherin. The expression of cleaved caspase-3 increased, while Bcl-2 decreased in each cell line following treatment with shHDGF and TMZ, as compared to TMZ alone. Furthermore, RNAi-based knockdown study revealed that HDGF is probably involved in the activation of both the PI3K/Akt and the TGF-β signaling pathways. Together, our data suggested that HDGF regulates glioma cell growth, apoptosis and epithelial-mesenchymal transition (EMT) probably through the Akt and the TGF-β signaling pathways. These results provide evidence that targeting HDGF or its downstream targets may lead to novel therapies for gliomas.

  15. A single gene target of an ETS-family transcription factor determines neuronal CO2-chemosensitivity

    DEFF Research Database (Denmark)

    Brandt, Julia P; Aziz-Zaman, Sonya; Juozaityte, Vaida;

    2012-01-01

    . We report here a mechanism that endows C. elegans neurons with the ability to detect CO(2). The ETS-5 transcription factor is necessary for the specification of CO(2)-sensing BAG neurons. Expression of a single ETS-5 target gene, gcy-9, which encodes a receptor-type guanylate cyclase, is sufficient...

  16. Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’-Diindolylmethane (DIM)

    Science.gov (United States)

    2007-08-01

    cancer cells. Front Biosci 2005;10:236-43. 34. Rahman KM, Aranha O, Sarkar FH. Indole-3-carbinol (I3C) induces apoptosis in tumorigenic but not in...by AKT and NF-kappaB pathways in prostate cancer cells. Front Biosci 2005;10:236-43. 27. Rahman KM, Aranha O, Sarkar FH. Indole-3-carbinol (I3C...breast cancer cells. Cancer research 1999;59:1244-51. 45. Rahman KM, Aranha O, Glazyrin A, Chinni SR, Sarkar FH. Translocation of Bax to mitochondria

  17. Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’diindolylmethane (DIM)

    Science.gov (United States)

    2006-08-01

    during I3C-induced apopto- sis in breast cancer cells. Nutr Cancer 2004;48:84–94. 5. Rahman KM, Aranha O, Glazyrin A, Chinni SR, Sarkar FH...Biochem Mol Biol 2002;80:191–201. 7. Rahman KM, Aranha O, Sarkar FH. Indole-3-carbinol (I3C) induces apoptosis in tumorigenic but not in non- tumorigenic...1011–9. 24. Rahman KM, Aranha O, Glazyrin A, et al. Translocation of Bax to mitochondria induces apoptotic cell death in indole-3-carbinol (I3C) treated

  18. Chemosensitization of Trypanosoma congolense strains resistant to isometamidium chloride by tetracyclines and enrofloxacin.

    Directory of Open Access Journals (Sweden)

    Vincent Delespaux

    Full Text Available BACKGROUND: Because of the development of resistance in trypanosomes to trypanocidal drugs, the livelihood of millions of livestock keepers in sub-Saharan Africa is threatened now more than ever. The existing compounds have become virtually useless and pharmaceutical companies are not keen on investing in the development of new trypanocides. We may have found a breakthrough in the treatment of resistant trypanosomal infections, through the combination of the trypanocide isometamidium chloride (ISM with two affordable veterinary antibiotics. METHODOLOGY/PRINCIPAL FINDINGS: In a first experiment, groups of mice were inoculated with Trypanosoma congolense strains resistant to ISM and either left untreated or treated with (i tetracycline, (ii ISM or (iii the combination of the antibiotic and the trypanocide. Survival analysis showed that there was a significant effect of treatment and resistance to treatment on the survival time. The groups treated with ISM (with or without antibiotic survived significantly longer than the groups that were not treated with ISM (P<0.01. The group treated with the combination trypanocide/antibiotic survived significantly longer than the group treated with ISM (P<0.01. In a second experiment, groups of cattle were inoculated with the same resistant trypanosome strain and treated with (i ISM, (ii ISM associated with oxytetracycline or (iii ISM associated with enrofloxacine. All animals treated with ISM became parasitaemic. In the groups treated with ISM-oxytetracycline and ISM-enrofloxacine, 50% of the animals were cured. Animals from the groups treated with a combination trypanocide/antibiotic presented a significantly longer prepatent period than animals treated with ISM (p<0.001. The impact of the disease on the haematocrit was low in all ISM treated groups. Yet, it was lower in the groups treated with the combination trypanocide/antibiotic (p<0.01. CONCLUSIONS/SIGNIFICANCE: After optimization of the administration protocol, this new therapeutic combination could constitute a promising treatment for livestock infected with drug resistant T. congolense.

  19. Escin Chemosensitizes Human Pancreatic Cancer Cells and Inhibits the Nuclear Factor-kappaB Signaling Pathway

    Directory of Open Access Journals (Sweden)

    A. Rimmon

    2013-01-01

    Full Text Available Background. There is an urgent need to develop new treatment strategies and drugs for pancreatic cancer that is highly resistant to radio-chemotherapy. Aesculus hippocastanum (the horse chestnut known in Chinese medicine as a plant with anti-inflammatory, antiedema, antianalgesic, and antipyretic activities. The main active compound of this plant is Escin (C54H84O23. Objective. To evaluate the effect of Escin alone and combined with chemotherapy on pancreatic cancer cell survival and to unravel mechanism(s of Escin anticancer activity. Methods. Cell survival was measured by XTT colorimetric assay. Synergistic effect of combined therapy was determined by CalcuSyn software. Cell cycle and induction of apoptosis were evaluated by FACS analysis. Expression of NF-κB-related proteins (p65, IκBα, and p-IκBα and cyclin D was evaluated by western blot analysis. Results. Escin decreased the survival of pancreatic cancer cells with IC50 = 10–20 M. Escin combined with gemcitabine showed only additive effect, while its combination with cisplatin resulted in a significant synergistic cytotoxic effect in Panc-1 cells. High concentrations of Escin induced apoptosis and decreased NF-κB-related proteins and cyclin D expression. Conclusions. Escin decreased pancreatic cancer cell survival, induced apoptosis, and downregulated NF-κB signaling pathway. Moreover, Escin sensitized pancreatic cancer cells to chemotherapy. Further translational research is required.

  20. Pharmacology of the mixed-function radio- and chemosensitizers CB 1954 and RSU 1069

    Energy Technology Data Exchange (ETDEWEB)

    Workman, P.; Walton, M.I.

    1984-08-01

    The authors have studied the pharmacokinetics and metabolism in mice of CB 1954 and RSU 1069. Containing both nitro and alkylating (aziridine) substituents, these are lead compounds in the mixed-function analogue series, which show particular promise for sensitizer development. Both compounds are degraded extensively, via pathways including nitro reduction, aziridine ring hydrolysis and aziridine ring removal. RSU 1069 was eliminated more rapidly than CB 1954. Tissue/plasma ratios tended to be rather lower than those for simple nitroimidazoles of intermediate lipophilicity, which are usually close to 100%. Nevertheless, tumor concentrations were consistent with potent sensitization. There is, however, scope for pharmacokinetic fine-tuning to modify tissue penetration as appropriate.

  1. Electrophysiological properties and chemosensitivity of guinea pig nodose ganglion neurons in vitro.

    Science.gov (United States)

    Undem, B J; Weinreich, D

    1993-07-01

    Conventional intracellular recording techniques were employed to obtain information on the electrophysiological and pharmacological characteristics of C-type neurons in the guinea pig nodose ganglia. Approximately 90% of the cell bodies gave rise to axons with conduction velocities consistent with C-fibers (0.9-1.1 m/s). The average resting membrane potential and input impedence was about -60 mV and 45 M sigma, respectively. Orthodromic electrical stimulation of the vagus nerve 20-30 mm caudal to the ganglion produced overshooting action potentials in the nodose neurons. The falling phase of the action potential was followed by a transient (50-300 ms) fast hyperpolarization (AHPfast). In 20% of C-type neurons the AHPfast was followed by a slowly developing, long-lasting afterhyperpolarization (AHPslow) that limited the ability of the neuron to fire action potentials at high frequency. The AHPslow magnitude was dependent on the number of spikes, had a reversal potential of -87 mV, and was abolished by 100 microM cadmium chloride, suggesting that it is produced by a calcium-dependent potassium current. In about 30% of the nodose neurons, hyperpolarizing current steps from resting potential produced a time- and voltage-dependent anomalous rectification in the electrotonic potential. External cesium (1 mM), but not barium (100 microM) reversibly blocked this effect. Single-electrode voltage-clamp measurements revealed a slowly developing inward current in these neurons that grows in magnitude with step hyperpolarizations from resting potential, and has an estimated reversal potential of about -44 mV. These properties suggest that this current is analogous to IH observed in many peripheral and central neurons. Autacoids including serotonin, histamine, several prostanoids, peptidoleukotriene, and bradykinin, were examined for their ability to affect the excitability of the nodose neurons. Serotonin was the only autacoid capable of depolarizing the membrane potential to action potential firing threshold. The serotonin-induced membrane depolarization was associated with a significant increase in input conductance. Histamine depolarized the membrane potential of the C-type neurons in 28/30 neurons. Bradykinin, prostacyclin, and leukotriene C4 were found to cause membrane depolarizations in a subset (73%, 31%, and 50%, respectively) of nodose neurons. The AHPslow was virtually abolished by bradykinin, prostacyclin, and in a subset of neurons, leukotriene C4. Inhibition of the AHPslow was accompanied by a change in the accommodative properties of the neurons, reflected by the increased frequency at which the neuron could successfully elicit repetitive action potentials.(ABSTRACT TRUNCATED AT 400 WORDS)

  2. Spectroscopic imaging system for high-throughput viability assessment of ovarian spheroids or microdissected tumor tissues (MDTs) in a microfluidic chip

    Science.gov (United States)

    St-Georges-Robillard, A.; Masse, M.; Kendall-Dupont, J.; Strupler, M.; Patra, B.; Jermyn, M.; Mes-Masson, A.-M.; Leblond, F.; Gervais, T.

    2016-02-01

    There is a growing effort in the biomicrosystems community to develop a personalized treatment response assay for cancer patients using primary cells, patient-derived spheroids, or live tissues on-chip. Recently, our group has developed a technique to cut tumors in 350 μm diameter microtissues and keep them alive on-chip, enabling multiplexed in vitro drug assays on primary tumor tissue. Two-photon microscopy, confocal microscopy and flow cytometry are the current standard to assay tissue chemosensitivity on-chip. While these techniques provide microscopic and molecular information, they are not adapted for high-throughput analysis of microtissues. We present a spectroscopic imaging system that allows rapid quantitative measurements of multiple fluorescent viability markers simultaneously by using a liquid crystal tunable filter to record fluorescence and transmittance spectra. As a proof of concept, 24 spheroids composed of ovarian cancer cell line OV90 were formed in a microfluidic chip, stained with two live cell markers (CellTrackerTM Green and Orange), and imaged. Fluorescence images acquired were normalized to the acquisition time and gain of the camera, dark noise was removed, spectral calibration was applied, and spatial uniformity was corrected. Spectral un-mixing was applied to separate each fluorophore's contribution. We have demonstrated that rapid and simultaneous viability measurements on multiple spheroids can be achieved, which will have a significant impact on the prediction of a tumor's response to multiple treatment options. This technique may be applied as well in drug discovery to assess the potential of a drug candidate directly on human primary tissue.

  3. Synergistic anti-glioma effect of a coloaded nano-drug delivery system

    Directory of Open Access Journals (Sweden)

    Xu H

    2016-12-01

    Full Text Available Huae Xu,1,* Feng Jia,2,* Pankaj Kumar Singh,3 Shu Ruan,4 Hao Zhang,5,* Xiaolin Li5 1Department of Pharmacy, The First Affiliated Hospital with Nanjing Medical University, Nanjing, 2Department of Neurosurgery, Yancheng City No 1 People’s Hospital, The Fourth Affiliated Hospital of Nantong Medical College, Yancheng, People’s Republic of China; 3Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; 4Department of Endocrinology, Yancheng Third Hospital, The Affiliated Hospital of Southeast University Medical College, Yancheng, 5Department of Geriatrics, The First Affiliated Hospital with Nanjing Medical University, Nanjing, People’s Republic of China *These authors contributed equally to this work Abstract: The anti-glioma effect of temozolomide (Tem is sometimes undermined by the emerging resistance. Recently, resveratrol (Res, herbal medicine extracted from grape seeds, has been demonstrated for its potential use in chemosensitization. In the current study, both these drugs were loaded simultaneously into nanoparticles with methoxy poly(ethylene glycol-poly epsilon caprolactone (mPEG-PCL as drug carriers in order to achieve better antitumor efficiency. Tem/Res-coloaded mPEG-PCL nanoparticles were constructed, characterized, and tested for antitumor effect on glioma cells by using in vitro and xenograft model system. The nanoparticle constructs were satisfactory with drug loading content (Res =~12.4%; Tem =~9.3% and encapsulation capacity of >85% for both the drugs. In addition, the coencapsulation led to better in vitro stability of the nanoparticles than Tem-loaded nanoparticles. An in vitro uptake study demonstrated a high uptake efficiency of the nanoparticles by glioma cells. The synergistic antitumor effect against glioma cells was observed in the combinational treatment of Res and Tem. Tem/Res-coloaded nanoparticles induced higher apoptosis in U87 glioma cells as

  4. System Budgets

    DEFF Research Database (Denmark)

    Jeppesen, Palle

    1996-01-01

    The lecture note is aimed at introducing system budgets for optical communication systems. It treats optical fiber communication systems (six generations), system design, bandwidth effects, other system impairments and optical amplifiers.......The lecture note is aimed at introducing system budgets for optical communication systems. It treats optical fiber communication systems (six generations), system design, bandwidth effects, other system impairments and optical amplifiers....

  5. Gradient systems and mechanical systems

    Institute of Scientific and Technical Information of China (English)

    Fengxiang Mei; Huibin Wu

    2016-01-01

    All types of gradient systems and their properties are discussed. Two problems connected with gradient sys-tems and mechanical systems are studied. One is the direct problem of transforming a mechanical system into a gradi-ent system, and the other is the inverse problem, which is transforming a gradient system into a mechanical system.

  6. Thermal systems; Systemes thermiques

    Energy Technology Data Exchange (ETDEWEB)

    Lalot, S. [Valenciennes Univ. et du Hainaut Cambresis, LME, 59 (France); Lecoeuche, S. [Ecole des Mines de Douai, Dept. GIP, 59 - Douai (France)]|[Lille Univ. des Sciences et Technologies, 59 - Villeneuve d' Ascq (France); Ahmad, M.; Sallee, H.; Quenard, D. [CSTB, 38 - Saint Martin d' Heres (France); Bontemps, A. [Universite Joseph Fourier, LEGI/GRETh, 38 - Grenoble (France); Gascoin, N.; Gillard, P.; Bernard, S. [Laboratoire d' Energetique, Explosion, Structure, 18 - Bourges (France); Gascoin, N.; Toure, Y. [Laboratoire Vision et Robotique, 18 - Bourges (France); Daniau, E.; Bouchez, M. [MBDA, 18 - Bourges (France); Dobrovicescu, A.; Stanciu, D. [Bucarest Univ. Polytechnique, Faculte de Genie Mecanique (Romania); Stoian, M. [Reims Univ. Champagne Ardenne, Faculte des Sciences, UTAP/LTM, 51 (France); Bruch, A.; Fourmigue, J.F.; Colasson, S. [CEA Grenoble, Lab. Greth, 38 (France); Bontemps, A. [Universite Joseph Fourier, LEGI/GRETh, 38 - Grenoble (France); Voicu, I.; Mare, T.; Miriel, J. [Institut National des Sciences Appliquees (INSA), LGCGM, IUT, 35 - Rennes (France); Galanis, N. [Sherbrooke Univ., Genie Mecanique, QC (Canada); Nemer, M.; Clodic, D. [Ecole des Mines de Paris, Centre Energetique et Procedes, 75 (France); Lasbet, Y.; Auvity, B.; Castelain, C.; Peerhossaini, H. [Nantes Univ., Ecole Polytechnique, Lab. de Thermocinetiquede Nantes, UMR-CNRS 6607, 44 (France)

    2005-07-01

    This session about thermal systems gathers 26 articles dealing with: neural model of a compact heat exchanger; experimental study and numerical simulation of the thermal behaviour of test-cells with walls made of a combination of phase change materials and super-insulating materials; hydraulic and thermal modeling of a supercritical fluid with pyrolysis inside a heated channel: pre-dimensioning of an experimental study; energy analysis of the heat recovery devices of a cryogenic system; numerical simulation of the thermo-hydraulic behaviour of a supercritical CO{sub 2} flow inside a vertical tube; mixed convection inside dual-tube exchangers; development of a nodal approach with homogenization for the simulation of the brazing cycle of a heat exchanger; chaotic exchanger for the cooling of low temperature fuel cells; structural optimization of the internal fins of a cylindrical generator; a new experimental approach for the study of the local boiling inside the channels of exchangers with plates and fins; experimental study of the flow regimes of boiling hydrocarbons on a bundle of staggered tubes; energy study of heat recovery exchangers used in Claude-type refrigerating systems; general model of Carnot engine submitted to various operating constraints; the free pistons Stirling cogeneration system; natural gas supplied cogeneration system with polymer membrane fuel cell; influence of the CRN coating on the heat flux inside the tool during the wood unrolling process; transport and mixture of a passive scalar injected inside the wake of a Ahmed body; control of a laser welding-brazing process by infrared thermography; 2D self-adaptative method for contours detection: application to the images of an aniso-thermal jet; exergy and exergy-economical study of an 'Ericsson' engine-based micro-cogeneration system; simplified air-conditioning of telephone switching equipments; parametric study of the 'low-energy' individual dwelling; brief synthesis of

  7. Data Systems vs. Information Systems

    OpenAIRE

    Amatayakul, Margret K.

    1982-01-01

    This paper examines the current status of “hospital information systems” with respect to the distinction between data systems and information systems. It is proposed that the systems currently existing are incomplete data dystems resulting in ineffective information systems.

  8. Multibody Systems

    DEFF Research Database (Denmark)

    Wagner, Falko Jens

    1999-01-01

    Multibody Systems is one area, in which methods for solving DAEs are of special interst. This chapter is about multibody systems, why they result in DAE systems and what kind of problems that can arise when dealing with multibody systems and formulating their corresponding DAE system....

  9. Arctigenin enhances chemosensitivity to cisplatin in human nonsmall lung cancer H460 cells through downregulation of survivin expression.

    Science.gov (United States)

    Wang, Huan-qin; Jin, Jian-jun; Wang, Jing

    2014-01-01

    Arctigenin, a dibenzylbutyrolactone lignan, enhances cisplatin-mediated cell apoptosis in cancer cells. Here, we sought to investigate the effects of arctigenin on cisplatin-treated non-small-cell lung cancer (NSCLC) H460 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and annexin-V/propidium iodide staining were performed to analyze the proliferation and apoptosis of H460 cells. Arctigenin dose-dependently suppressed cell proliferation and potentiated cell apoptosis, coupled with increased cleavage of caspase-3 and poly(ADP-ribose) polymerase. Moreover, arctigenin sensitized H460 cells to cisplatin-induced proliferation inhibition and apoptosis. Arctigenin alone or in combination with cisplatin had a significantly lower amount of survivin. Ectopic expression of survivin decreased cell apoptosis induced by arctigenin (P arctigenin (P arctigenin has a therapeutic potential in combina-tion with chemotherapeutic agents for NSLC.

  10. An illegitimate microRNA target site within the 3' UTR of MDM4 affects ovarian cancer progression and chemosensitivity

    DEFF Research Database (Denmark)

    Wynendaele, Jessika; Böhnke, Anja; Leucci, Eleonora

    2010-01-01

    Overexpression of MDM4 (also known as MDMX or HDMX) is thought to promote tumorigenesis by decreasing p53 tumor suppressor function. Even modest decrease in Mdm4 levels affects tumorigenesis in mice, suggesting that genetic variants of MDM4 might have similar effects in humans. We sequenced the MDM......4 gene in a series of ovarian cancer cell lines and carcinomas to identify mutations and/or single nucleotide polymorphisms (SNPs). We identified an SNP (SNP34091) in the 3'-UTR of MDM4 that creates a putative target site for hsa-miR-191, a microRNA that is highly expressed in normal and tumor...... tissues. Biochemical evidence supports specific miR-191-dependent regulation of the MDM4-C, but not MDM4-A, variant. Consistently, the A-allele was associated with statistically significant increased expression of MDM4 mRNA and protein levels in ovarian carcinomas. Importantly, the wild-type genotype (A...

  11. Bone morphogenetic protein 2 (BMP2) induces growth suppression and enhances chemosensitivity of human colon cancer cells

    DEFF Research Database (Denmark)

    Vishnubalaji, Radhakrishnan; Yue, Shijun; Alfayez, Musaad

    2016-01-01

    datasets revealed significant downregulation of BMP2 in metastatic recurrent compared to non-metastatic cancer (p = 0.02). Global gene expression analysis in CRC cells over-expressing BMP2 revealed multiple dysregulated pathways mostly affecting cell cycle and DNA damage response. Concordantly, lentiviral......BACKGROUND: Molecular profiling of colorectal cancer (CRC) based on global gene expression has revealed multiple dysregulated signalling pathways associated with drug resistance and poor prognosis. However, the role of BMP2 signaling in CRC is not fully characterised. METHODS: Bioinformatics data...... expression were assessed using qRT-PCR. AlamarBlue assay was used to assess cell viability in vitro. In vivo experiments were conducted using SCID mice. RESULTS: Our data revealed frequent downregulation of BMP2 in primary CRC tissues. Additionally, interrogation of publically available gene expression...

  12. Impact of immunohistochemistry-based molecular subtype on chemosensitivity and survival in Hispanic breast cancer patients following neoadjuvant chemotherapy

    Science.gov (United States)

    Gómez, Rodolfo; Ossa, Carlos Andrés; Montoya, María Elvira; Echeverri, Carolina; Ángel, Gonzalo; Ascuntar, Johana; Borrero, Mauricio; Gil, Mónica; Herrera, Sabrina; Gutiérrez, Eduardo; Herazo, Fernando; Jiménez, Alejo; Madrid, Jorge; Reyes, Pedro Alejandro; Zuluaga, Lina; García, Héctor

    2015-01-01

    Background Neoadjuvant chemotherapy (NAC) is the standard treatment for patients with locally advanced breast cancer, showing improvement in disease-free survival (DFS) and overall survival (OS) rates in patients achieving pathological complete response (pCR). The relationship between immunohistochemistry-based molecular subtyping (IMS), chemo sensitivity and survival is currently a matter of interest. We explore this relationship in a Hispanic cohort of breast cancer patients treated with NAC. Methods A retrospective survival analysis was performed on Colombian females with breast cancer treated at Instituto de Cancerología-Clinica Las Américas between January 2009 and December 2011. Patients were classified according to immunohistochemistry-based subtyping into the following five groups: Luminal A, Luminal B, Luminal B/HER 2+, HER2-enriched, and triple-negative breast cancer. Demographic characteristics, recurrence pattern, and survival rate were reviewed by bivariate and multivariate analysis. Results A total of 328 patients fulfilled the study’s inclusion parameters and the distribution of subtypes were as follows: Luminal A: 73 (22.3%), Luminal B/HER2−: 110 (33.5%), Luminal B/HER2+: 75 (22.9%), HER2-enriched: 30 (9.1%), and triple-negative: 40 (12.2%). The median follow-up was 41 months (interquartile range: 31–52). Pathological response to NAC was as follows: complete pathological response (pCR) in 28 (8.5%) patients, partial 247 (75.3%); stable disease 47 (14.3%), and progression 6 (1.8%) patients. The presence of pCR had a significant DFS and OS in the entire group (p = 0.01) but subtypes had different DFS in Luminal B (p = 0.01) and triple negative (p = 0.02) and also OS in Luminal B (p = 0.01) and triple negative (p = 0.01). Conclusions pCR is associated with an improved overall survival and disease-free survival rates in this group of Hispanics patients. Advanced stages, Luminal B subtypes, triple-negative tumours and non-pCR showed lower DFS. PMID:26316883

  13. MiR-100 Inhibits Osteosarcoma Cell Proliferation, Migration, and Invasion and Enhances Chemosensitivity by Targeting IGFIR.

    Science.gov (United States)

    Liu, Yang; Zhu, Shu-Tao; Wang, Xiao; Deng, Jun; Li, Wei-Hua; Zhang, Peng; Liu, Bing-Shan

    2016-10-01

    MicroRNAs are highly conserved noncoding RNA that negatively modulate protein expression at a posttranscriptional and/or translational level. MicroRNAs play an important role in the development and progression of human cancers, including osteosarcoma. Recent studies have shown that miR-100 was downregulated in many cancers; however, the role of miR-100 in human osteosarcoma has not been totally elucidated. In this study, we demonstrate that the expression of miR-100 was significantly downregulated in human osteosarcoma tissues compared to the adjacent tissues. Enforced expression of miR-100 inhibited cell proliferation, migration, and invasion abilities of osteosarcoma cells, U-2OS, and MG-63. Additionally, miR-100 also sensitized osteosarcoma cells to cisplatin and promoted apoptosis. Furthermore, overexpression of miR-100 decreased the expression of insulin-like growth factor I receptor and inhibited PI3K/AKT and MAPK/ERK signaling. In human clinical specimens, insulin-like growth factor I receptor was inversely correlated with miR-100 in osteosarcoma tissues. Collectively, our results demonstrate that miR-100 is a tumor suppressor microRNA and indicate its potential application for the treatment of osteosarcoma in future.

  14. DNA methylation and histone acetylation regulate the expression of MGMT and chemosensitivity to temozolomide in malignant melanoma cell lines.

    Science.gov (United States)

    Chen, Ya-Ping; Hou, Xiao-Yang; Yang, Chun-Sheng; Jiang, Xiao-Xiao; Yang, Ming; Xu, Xi-Feng; Feng, Shou-Xin; Liu, Yan-Qun; Jiang, Guan

    2016-08-01

    Malignant melanoma is an aggressive, highly lethal dermatological malignancy. Chemoresistance and rapid metastasis limit the curative effect of multimodal therapies like surgery or chemotherapy. The suicide enzyme O6-methylguanine-DNA methyltransferase (MGMT) removes adducts from the O6-position of guanine to repair DNA damage. High MGMT expression is associated with resistance to therapy in melanoma. However, it is unknown if MGMT is regulated by DNA methylation or histone acetylation in melanoma. We examined the effects of the DNA methylation inhibitor 5-Aza-2'-deoxycytidine and histone deacetylase inhibitor Trichostatin A alone or in combination on MGMT expression and promoter methylation and histone acetylation in A375, MV3, and M14 melanoma cells. This study demonstrates that MGMT expression, CpG island methylation, and histone acetylation vary between melanoma cell lines. Combined treatment with 5-Aza-2'-deoxycytidine and Trichostatin A led to reexpression of MGMT, indicating that DNA methylation and histone deacetylation are associated with silencing of MGMT in melanoma. This study provides information on the role of epigenetic modifications in malignant melanoma that may enable the development of new strategies for treating malignant melanoma.

  15. p53 induces formation of NEAT1 lncRNA-containing paraspeckles that modulate replication stress response and chemosensitivity.

    Science.gov (United States)

    Adriaens, Carmen; Standaert, Laura; Barra, Jasmine; Latil, Mathilde; Verfaillie, Annelien; Kalev, Peter; Boeckx, Bram; Wijnhoven, Paul W G; Radaelli, Enrico; Vermi, William; Leucci, Eleonora; Lapouge, Gaëlle; Beck, Benjamin; van den Oord, Joost; Nakagawa, Shinichi; Hirose, Tetsuro; Sablina, Anna A; Lambrechts, Diether; Aerts, Stein; Blanpain, Cédric; Marine, Jean-Christophe

    2016-08-01

    In a search for mediators of the p53 tumor suppressor pathway, which induces pleiotropic and often antagonistic cellular responses, we identified the long noncoding RNA (lncRNA) NEAT1. NEAT1 is an essential architectural component of paraspeckle nuclear bodies, whose pathophysiological relevance remains unclear. Activation of p53, pharmacologically or by oncogene-induced replication stress, stimulated the formation of paraspeckles in mouse and human cells. Silencing Neat1 expression in mice, which prevents paraspeckle formation, sensitized preneoplastic cells to DNA-damage-induced cell death and impaired skin tumorigenesis. We provide mechanistic evidence that NEAT1 promotes ATR signaling in response to replication stress and is thereby engaged in a negative feedback loop that attenuates oncogene-dependent activation of p53. NEAT1 targeting in established human cancer cell lines induced synthetic lethality with genotoxic chemotherapeutics, including PARP inhibitors, and nongenotoxic activation of p53. This study establishes a key genetic link between NEAT1 paraspeckles, p53 biology and tumorigenesis and identifies NEAT1 as a promising target to enhance sensitivity of cancer cells to both chemotherapy and p53 reactivation therapy.

  16. Pristimerin causes G1 arrest, induces apoptosis, and enhances the chemosensitivity to gemcitabine in pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Yongwei Wang

    Full Text Available Despite rapid advances in chemotherapy and surgical resection strategies, pancreatic cancer remains the fourth leading cause of cancer related deaths in the United States with a 5-year survival rate of less than 5%. Therefore, novel therapeutic agents for the prevention and treatment of pancreatic cancer are urgently needed. The aim of this study was to investigate the effect of pristimerin, a quinonemethide triterpenoid compound isolated from Celastraceae and Hippocrateaceae, on inhibition of cell proliferation and induction of apoptosis in three pancreatic cancer cells, BxPC-3, PANC-1 and AsPC-1, in both monotherapy and in combination with gemcitabine. Treatment with pristimerin decreased the cell proliferation of all three pancreatic cancer cells in a dose- and time-dependent manner. Treatment of pancreatic cancer cells with pristimerin also resulted in G1-phase arrest which was strongly associated with a marked decrease in the level of cyclins (D1 and E and cyclin-dependent kinases (cdk2, cdk4 and cdk6 with concomitant induction of WAF1/p21 and KIP1/p27. Pristimerin treatment also resulted in apoptotic cell death, cleavage of caspase-3, modulation in the expressions of Bcl-2 family proteins, inhibition of the translocation and DNA-binding activity of NF-κB. In addition, pristimerin potentiated the growth inhibition and apoptosis inducing effects of gemcitabine in all three pancreatic cancer cells, at least in part, by inhibiting constitutive as well as gemcitabine-induced activation of NF-κB in both its DNA-binding activity and transcriptional activity. Taken together, these data provide the first evidence that pristimerin has strong potential for development as a novel agent against pancreatic cancer.

  17. Quinazoline derivatives are efficient chemosensitizers of antibiotic activity in Enterobacter aerogenes, Klebsiella pneumoniae and Pseudomonas aeruginosa resistant strains.

    Science.gov (United States)

    Chevalier, Jacqueline; Mahamoud, Abdallah; Baitiche, Milad; Adam, Elissavet; Viveiros, Miguel; Smarandache, Adriana; Militaru, Andra; Pascu, Mihail L; Amaral, Leonard; Pagès, Jean-Marie

    2010-08-01

    Amongst the three series of quinazoline derivatives synthesised and studied in this work, some molecules increase the antibiotic susceptibility of Gram-negative bacteria presenting multidrug-resistant phenotypes. N-alkyl compounds induced an increase in the activity of chloramphenicol, nalidixic acid and sparfloxacin, which are substrates of the AcrAB-TolC and MexAB-OprM efflux pumps in clinical isolates. These molecules are able to increase the intracellular concentration of chloramphenicol in efflux pump-overproducing strains. Their activity depends on the antibiotic structure, suggesting that different sites may be involved for the recognition of substrates by a given efflux pump. Quinazoline molecules exhibiting a nitro functional group are more active, and structure-activity relationship studies may be undertaken to identify the pharmacophoric group involved in the AcrB and MexB affinity sites.

  18. Central Respiratory Chemosensitivity and Cerebrovascular CO[subscript 2] Reactivity: A Rebreathing Demonstration Illustrating Integrative Human Physiology

    Science.gov (United States)

    MacKay, Christina M.; Skow, Rachel J.; Tymko, Michael M.; Boulet, Lindsey M.; Davenport, Margie H.; Steinback, Craig D.; Ainslie, Philip N.; Lemieux, Chantelle C. M.; Day, Trevor A.

    2016-01-01

    One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations…

  19. Metal Occupancy of Zinc Finger Motifs as Determinants for Zn2+-Mediated Chemosensitization of Prostate Cancer Cells

    Science.gov (United States)

    2013-12-01

    effects of docetaxel chemotherapy similar treatment does not result in increased Zn2+ levels in prostate cancer cells or protect these cells from...HtrA2 is located in the mitochondria , however upon pro-apoptotic stimulation processed Omi/HtrA2 translocates into the cytosol and binds XIAP...sequestration into endosomes, lysososmes or other organelles while FluoZin fluorescence was diffuse consistent with predominantly cytoplasmic distribution

  20. RNA interference targeting extracellular matrix metalloproteinase inducer (CD147) inhibits growth and increases chemosensitivity in human cervical cancer cells.

    Science.gov (United States)

    Zhang, F; Zeng, Y L; Zhang, X G; Chen, W J; Yang, R; Li, S J

    2013-01-01

    Overexpression of extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN CD147) has been implicated in the growth and survival of malignant cells. However, its presence and role in cervical cancer cells has not been well-studied. In the present study, small interfering RNA (siRNA) was designed and synthesized to breakdown the expression of CD147. The present data demonstrated that 24 and 48 hours after transfecting CD147 siRNA, both the CD147 mRNA and protein expression were significantly inhibited as determined by quantitative real-time polymerase chain reaction (RT-PCR) and immunocytochemistry. Meanwhile, simultaneous silencing of CD147 resulted in distinctly increasing MMP-9, VEGF, and MDR-1. Further studies demonstrated decreased CD147 expression, resulted in G1/S phase transition with flow cytometry analysis, as well as the resistance of the cells to 5-FU. These findings provide further evidence that CD147 may become a promising therapeutic target for human cervical cancer and a potential chemotherapy-sensitizing agent.

  1. Enhanced chemosensitization in multidrug-resistant human breast cancer cells by inhibition of IL-6 and IL-8 production.

    Science.gov (United States)

    Shi, Zhi; Yang, Wei-Min; Chen, Li-Pai; Yang, Dong-Hua; Zhou, Qi; Zhu, Jin; Chen, Jun-Jiang; Huang, Ruo-Chun; Chen, Zhe-Sheng; Huang, Ruo-Pan

    2012-10-01

    Drug resistance remains a major hurdle to successful cancer treatment. Many mechanisms such as overexpression of multidrug-resistance related proteins, increased drug metabolism, decreased apoptosis, and impairment of signal transduction pathway can contribute multidrug resistance (MDR). Recent studies strongly suggest a close link between cytokines and drug resistance. To identify new targets involved in drug resistance, we established a multidrug-resistant human breast cancer cell line MCF-7/R and examined the cytokine profile using cytokine antibody array technology. Among 120 cytokines/chemokines screened, IL-6, IL-8, and 13 other proteins were found to be markedly increased in drug-resistant MCF-7/R cell line as compared to sensitive MCF-7/S cell line, while 7 proteins were specifically reduced in drug-resistant MCF-7/R cells. Neutralizing antibodies against IL-6 and IL-8 partially reversed the drug resistance of MCF-7/R to paclitaxel and doxorubicin, while a neutralizing antibody against MCP-1 had no significant effect. Inhibition of endogenous IL-6 or IL-8 by siRNA technology significantly enhanced drug sensitivity of MCF-7/R cells. Furthermore, overexpression of IL-6 or IL-8 expression by transfection increased the ADM resistance in MCF-7/S cells. Our data suggest that increased expression levels of IL-6 and IL-8 may contribute to MDR in human breast cancer cells.

  2. Establishment, characterization and chemosensitivity of three mismatch repair deficient cell lines from sporadic and inherited colorectal carcinomas.

    Directory of Open Access Journals (Sweden)

    Claudia Maletzki

    Full Text Available BACKGROUND: Colorectal cancer (CRC represents a morphologic and molecular heterogenic disease. This heterogeneity substantially impairs drug effectiveness and prognosis. The subtype of mismatch repair deficient (MMR-D CRCs, accounting for about 15% of all cases, shows particular differential responses up to resistance towards currently approved cytostatic drugs. Pre-clinical in vitro models representing molecular features of MMR-D tumors are thus mandatory for identifying biomarkers that finally help to predict responses towards new cytostatic drugs. Here, we describe the successful establishment and characterization of three patient-derived MMR-D cell lines (HROC24, HROC87, and HROC113 along with their corresponding xenografts. METHODOLOGY: MMR-D cell lines (HROC24, HROC87, and HROC113 were established from a total of ten clinicopathological well-defined MMR-D cases (120 CRC cases in total. Cells were comprehensively characterized by phenotype, morphology, growth kinetics, invasiveness, and molecular profile. Additionally, response to clinically relevant chemotherapeutics was examined in vitro and in vivo. PRINCIPAL FINDINGS: Two MMR-D lines showing CIMP-H derived from sporadic CRC (HROC24: K-ras(wt, B-raf(mut, HROC87: K-ras(wt, B-raf(mut, whereas the HROC113 cell line (K-ras(mut, B-raf(wt was HNPCC-associated. A diploid DNA-status could be verified by flow cytometry and SNP Array analysis. All cell lines were characterized as epithelial (EpCAM(+ tumor cells, showing surface tumor marker expression (CEACAM(+. MHC-class II was inducible by Interferon-γ stimulation. Growth kinetics as well as invasive potential was quite heterogeneous between individual lines. Besides, MMR-D cell lines exhibited distinct responsiveness towards chemotherapeutics, even when comparing in vitro and in vivo sensitivity. CONCLUSIONS: These newly established and well-characterized, low-passage MMR-D cell lines provide a useful tool for future investigations on the biological characteristics of MMR-D CRCs, both of sporadic and hereditary origin. Additionally, matched patient-derived immune cells allow for comparative genetic studies.

  3. Inhibition of the JAK-STAT3 pathway by andrographolide enhances chemosensitivity of cancer cells to doxorubicin.

    Science.gov (United States)

    Zhou, Jing; Ong, Choon-Nam; Hur, Gang-Min; Shen, Han-Ming

    2010-05-01

    Andrographolide (Andro), a diterpenoid lactone isolated from a traditional herbal medicine Andrographis paniculata, is known to possess potent anti-inflammatory and anticancer properties. In this study, we sought to examine the effect of Andro on signal transducer and activator of transcription 3 (STAT3) pathway and evaluate whether suppression of STAT3 activity by Andro could sensitize cancer cells to a chemotherapeutic drug doxorubicin. First, we demonstrated that Andro is able to significantly suppress both constitutively activated and IL-6-induced STAT3 phosphorylation and subsequent nuclear translocation in cancer cells. Such inhibition is found to be achieved through suppression of Janus-activated kinase (JAK)1/2 and interaction between STAT3 and gp130. For understanding the biological significance of the inhibitory effect of Andro on STAT3, we next investigated the effect of Andro on doxorubicin-induced apoptosis in human cancer cells. In our study the constitutive activation level of STAT3 was found to be correlated to the resistance of cancer cells to doxorubicin-induced apoptosis. Both the short-term MTT assay and the long-term colony formation assay showed that Andro dramatically promoted doxorubicin-induced cell death in cancer cells, indicating that Andro enhances the sensitivity of cancer cells to doxorubicin mainly via STAT3 suppression. These observations thus reveal a novel anticancer function of Andro and suggest a potential therapeutic strategy of using Andro in combination with chemotherapeutic agents for treatment of cancer.

  4. Proteasome subunit expression analysis and chemosensitivity in relapsed paediatric acute leukaemia patients receiving bortezomib-containing chemotherapy

    Directory of Open Access Journals (Sweden)

    Denise Niewerth

    2016-09-01

    Full Text Available Abstract Background Drug combinations of the proteasome inhibitor bortezomib with cytotoxic chemotherapy are currently evaluated in phase 2 and 3 trials for the treatment of paediatric acute myeloid leukaemia (AML and acute lymphocytic leukaemia (ALL. Methods We investigated whether expression ratios of immunoproteasome to constitutive proteasome in leukaemic cells correlated with response to bortezomib-containing re-induction chemotherapy in patients with relapsed and refractory acute leukaemia, enrolled in two Children’s Oncology Group phase 2 trials of bortezomib for ALL (COG-AALL07P1 and AML (COG-AAML07P1. Expression of proteasome subunits was examined in 72 patient samples (ALL n = 60, AML n = 12 obtained before start of therapy. Statistical significance between groups was determined by Mann-Whitney U test. Results Ratios of immunoproteasome to constitutive proteasome subunit expression were significantly higher in pre-B ALL cells than in AML cells for both β5i/β5 and β1i/β1 subunits (p = 0.004 and p < 0.001. These ratios correlated with therapy response in AML patients; β1i/β1 ratios were significantly higher (p = 0.028 between patients who did (n = 4 and did not reach complete remission (CR (n = 8, although for β5i/β5 ratios, this did not reach significance. For ALL patients, the subunit ratios were also higher for patients who showed a good early response to therapy but this relation was not statistically significant. Overall, for this study, the patients were treated with combination therapy, so response was not only attributed to proteasome inhibition. Moreover, the leukaemic blast cells were not purified for these samples. Conclusions These first ex vivo results encourage further studies into relative proteasome subunit expression to improve proteasome inhibition-containing therapy and as a potential indicator of bortezomib response in acute leukaemia.

  5. Enhanced chemosensitivity of p73α gene transferred into H1299 cell line of human lung adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    HE Yong; FAN Shi-zhi; Kalkunte S Srivenugopal; JIANG Yao-guang; QIN Chuan

    2004-01-01

    Objective: To study the effects of transferred wild type p73α gene on the sensitivity to the chemotherapeutic agents and the growth of p53-null H1299 cells of human lung adenocarcinoma. Methods: The pcDNA3-HA-p73α plasmid was transferred into the cultured p53-null H1299 cells of human lung adenocarcinoma with the mediation of Dosper liposome;The cells resistant to G418 were selected. The expression of p73α gene in the cells was examined with Western blot. MTT assay was used to analyze the response of the transfected cells to cis-dichlorodiamine platinum (cDDP) and adriamycin (ADM). The rate of drug-induced apoptosis of the transfected cells was determined with flow cytometry and DNA fragmentation assay. The changes of the biological behaviors were observed with colony formation assay. Results: The transfected H1299 cells of human lung adenocarcinoma over-expressed p73α protein stably. MTT assay showed that the IC50 values of cDDP and ADM were reduced by approximately 7 fold and 130 fold respectively in the transfected cells as compared with the untransfected ones. Lower concentration of the chemotherapeutic agents ( 1.25 μmol/L of cDDP and 0.05 μmol/L of ADM)could be employed to suppress markedly the growth of the transfected H1299 cells. The apoptotic rate induced by cDDP was increased from 10.1% to 38.4% ( P < 0.01 ) and that of ADM from 12.1% to 49.3 % ( P < 0.01 ). The clonogenecity after the administration of chemotherapeutic agents was significantly lower in the transfected H1299 cells than in the parental cells (P < 0.01). The sensitive enhancement ratios were 1.8 and 2.6 for cDDP and ADM respectively. Conclusion: The transfection of H1299 cells with wild type p73α gene results in an increase of the sensitivity of the cells to chemotherapeutic agents.

  6. Systems effectiveness

    CERN Document Server

    Habayeb, A R

    1987-01-01

    Highlights three principal applications of system effectiveness: hardware system evaluation, organizational development and evaluation, and conflict analysis. The text emphasizes the commonality of the system effectiveness discipline. The first part of the work presents a framework for system effectiveness, partitioning and hierarchy of hardware systems. The second part covers the structure, hierarchy, states, functions and activities of organizations. Contains an extended Appendix on mathematical concepts and also several project suggestions.

  7. Intelligent Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The autonomous systems (AS) project, led by NASA Ames, is developing software for system operation automation. AS technology will help astronauts make more decisions...

  8. Systemic Assurance

    Science.gov (United States)

    2015-07-31

    storage devices (such as disk drives and SSDs) as well as a wide range of embedded controls. This phenomenon has been labeled the Internet of Things ( IoT ...environment involves interlinking with other systems, working in coalitions, relying on civil infrastructure, and use of personal devices . • Modern systems...The system-of-system approach can also involve use of mobile devices , forward-deployed capabilities for managing and analyzing large amounts of data

  9. Expert System

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas Troels; Cattani, Gian Luca

    2016-01-01

    An expert system is a computer system for inferring knowledge from a knowledge base, typically by using a set of inference rules. When the concept of expert systems was introduced at Stanford University in the early 1970s, the knowledge base was an unstructured set of facts. Today the knowledge b...

  10. Retrofitting Systems

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    This report gives an overview of the different retrofitting possibilities that are available today. The report looks at both external and internal systems for external wall constructions, roof constructions, floor constructions and foundations. All systems are described in detail in respect to use...... and methods, and the efficiency of the different systems are discussed....

  11. Systems Engineering

    Science.gov (United States)

    Pellerano, Fernando

    2015-01-01

    This short course provides information on what systems engineering is and how the systems engineer guides requirements, interfaces with the discipline leads, and resolves technical issues. There are many system-wide issues that either impact or are impacted by the thermal subsystem. This course will introduce these issues and illustrate them with real life examples.

  12. Operating systems

    CERN Document Server

    Tsichritzis, Dionysios C; Rheinboldt, Werner

    1974-01-01

    Operating Systems deals with the fundamental concepts and principles that govern the behavior of operating systems. Many issues regarding the structure of operating systems, including the problems of managing processes, processors, and memory, are examined. Various aspects of operating systems are also discussed, from input-output and files to security, protection, reliability, design methods, performance evaluation, and implementation methods.Comprised of 10 chapters, this volume begins with an overview of what constitutes an operating system, followed by a discussion on the definition and pr

  13. Cryogenic Systems

    Science.gov (United States)

    Hosoyama, Kenji

    2002-02-01

    In this lecture we discuss the principle of method of cooling to a very low temperature, i.e. cryogenic. The "gas molecular model" will be introduced to explain the mechanism cooling by the expansion engine and the Joule-Thomson expansion valve. These two expansion processes are normally used in helium refrigeration systems to cool the process gas to cryogenic temperature. The reverse Carnot cycle will be discussed in detail as an ideal refrigeration cycle. First the fundamental process of liquefaction and refrigeration cycles will be discussed, and then the practical helium refrigeration system. The process flow of the system and the key components; -compressor, expander, and heat exchanger- will be discussed. As an example of an actual refrigeration system, we will use the cryogenic system for the KEKB superconducting RF cavity. We will also discuss the liquid helium distribution system, which is very important, especially for the cryogenic systems used in accelerator applications. 1 Principles of Cooling and Fundamental Cooling Cycle 2 Expansion engine, Joule-Thomson expansion, kinetic molecular theory, and enthalpy 3 Liquefaction Systems 4 Refrigeration Systems 5 Practical helium liquefier/refrigeration system 6 Cryogenic System for TRISTAN Superconducting RF Cavity

  14. Material Systems

    DEFF Research Database (Denmark)

    Jensen, Mads Brath; Mortensen, Henrik Rubæk; Mullins, Michael;

    2009-01-01

    This paper describes and reflects upon the results of an investigative project which explores the setting up of a material system - a parametric and generative assembly consisting of and taking into consideration material properties, manufacturing constraints and geometric behavior. The project...... approaches the subject through the construction of a logic-driven system aiming to explore the possibilities of a material system that fulfills spatial, structural and performative requirements concurrently and how these are negotiated in situations where they might be conflicting....

  15. Recommender systems

    CERN Document Server

    Kembellec, Gérald; Saleh, Imad

    2014-01-01

    Acclaimed by various content platforms (books, music, movies) and auction sites online, recommendation systems are key elements of digital strategies. If development was originally intended for the performance of information systems, the issues are now massively moved on logical optimization of the customer relationship, with the main objective to maximize potential sales. On the transdisciplinary approach, engines and recommender systems brings together contributions linking information science and communications, marketing, sociology, mathematics and computing. It deals with the understan

  16. Energetic Systems

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetic Systems Division provides full-spectrum energetic engineering services (project management, design, analysis, production support, in-service support,...

  17. Intelligent systems

    CERN Document Server

    Irwin, J David

    2011-01-01

    Technology has now progressed to the point that intelligent systems are replacing humans in the decision making processes as well as aiding in the solution of very complex problems. In many cases intelligent systems are already outperforming human activities. Artificial neural networks are not only capable of learning how to classify patterns, such images or sequence of events, but they can also effectively model complex nonlinear systems. Their ability to classify sequences of events is probably more popular in industrial applications where there is an inherent need to model nonlinear system

  18. Systemic darwinism.

    Science.gov (United States)

    Winther, Rasmus Grønfeldt

    2008-08-19

    Darwin's 19th century evolutionary theory of descent with modification through natural selection opened up a multidimensional and integrative conceptual space for biology. We explore three dimensions of this space: explanatory pattern, levels of selection, and degree of difference among units of the same type. Each dimension is defined by a respective pair of poles: law and narrative explanation, organismic and hierarchical selection, and variational and essentialist thinking. As a consequence of conceptual debates in the 20th century biological sciences, the poles of each pair came to be seen as mutually exclusive opposites. A significant amount of 21st century research focuses on systems (e.g., genomic, cellular, organismic, and ecological/global). Systemic Darwinism is emerging in this context. It follows a "compositional paradigm" according to which complex systems and their hierarchical networks of parts are the focus of biological investigation. Through the investigation of systems, Systemic Darwinism promises to reintegrate each dimension of Darwin's original logical space. Moreover, this ideally and potentially unified theory of biological ontology coordinates and integrates a plurality of mathematical biological theories (e.g., self-organization/structure, cladistics/history, and evolutionary genetics/function). Integrative Systemic Darwinism requires communal articulation from a plurality of perspectives. Although it is more general than these, it draws on previous advances in Systems Theory, Systems Biology, and Hierarchy Theory. Systemic Darwinism would greatly further bioengineering research and would provide a significantly deeper and more critical understanding of biological reality.

  19. Immune System

    NARCIS (Netherlands)

    Kuper, C.F.; Ruehl-Fehlert, C.; Elmore, S.A.; Parker, G.A.

    2013-01-01

    Cells of the immune system are found in every organ, from the classic lymphoid organs to tissues such as liver, mucosae, and omental adipose tissue. Toxicity to the immune system may be from a direct or indirect injury to lymphoid organs. The morphological responses range from lymphocyte depletion t

  20. Linear Systems.

    Science.gov (United States)

    The report documents a series of seminars at Rome Air Development Center with the content equivalent to an intense course in Linear Systems . Material...is slanted toward the practicing engineer and introduces some of the fundamental concepts and techniques for analyzing linear systems . Techniques for

  1. Caste System

    OpenAIRE

    Hoff, Karla

    2016-01-01

    In standard economics, individuals are rational actors and economic forces undermine institutions that impose large inefficiencies. The persistence of the caste system is evidence of the need for psychologically more realistic models of decision-making in economics. The caste system divides South Asian society into hereditary groups whose lowest ranks are represented as innately polluted. ...

  2. cardiovascular system

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    6.1 Cardiac arrhythmias 2006037 Electroanatomical systems guided circumferential pulmonary veins ablation for atrial fibrillation: initial experience from comparison between the EnSite -NavX and CARTO system LIU Xu(刘旭 ), et al. Dept Cardiol, Shanghai Chest Hosp, Shanghai, 200030, China. Chin J Cardiol 2005; 33 (22): 975 -978.

  3. Power system

    Science.gov (United States)

    Hickam, Christopher Dale

    2008-03-18

    A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

  4. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems......, the need for mathematically based formal methodology is increasingly important. There are many books that look at particular methodologies for such systems. This book offers a more balanced introduction for graduate students and describes the various approaches, their strengths and weaknesses, and when...... they are best used. Milner's CCS and its operational semantics are introduced, together with the notions of behavioural equivalences based on bisimulation techniques and with recursive extensions of Hennessy-Milner logic. In the second part of the book, the presented theories are extended to take timing issues...

  5. Physical Systems

    CERN Document Server

    Belkind, Ori

    2012-01-01

    Based on the concept of a physical system, this book offers a new philosophical interpretation of classical mechanics and the Special Theory of Relativity. According to Belkind's view the role of physical theory is to describe the motions of the parts of a physical system in relation to the motions of the whole. This approach provides a new perspective into the foundations of physical theory, where motions of parts and wholes of physical systems are taken to be fundamental, prior to spacetime, material properties and laws of motion. He defends this claim with a constructive project, deriving b

  6. Dynamical systems

    CERN Document Server

    Sternberg, Shlomo

    2010-01-01

    Celebrated mathematician Shlomo Sternberg, a pioneer in the field of dynamical systems, created this modern one-semester introduction to the subject for his classes at Harvard University. Its wide-ranging treatment covers one-dimensional dynamics, differential equations, random walks, iterated function systems, symbolic dynamics, and Markov chains. Supplementary materials offer a variety of online components, including PowerPoint lecture slides for professors and MATLAB exercises.""Even though there are many dynamical systems books on the market, this book is bound to become a classic. The the

  7. Avionics Systems

    Directory of Open Access Journals (Sweden)

    P.M. Soundar Rajan

    2013-03-01

    Full Text Available ‘Avionics’ systems, over the decades, have grown from simple communication radios and navigation equipments to complex integrated equipments primarily infiuenced by dominance of digital technology. Continuous growth in integrated circuit technology, functional integration of complete system on chip, very high speed communication channels and fault tolerant communication protocols have brought remarkable advancements in avionics systems. Further Mechanical and Pneumatic functional blocks are being replaced by digital systems progressively and decisively. New generation aircraft are being built around powerful avionics assets to provide stress free cockpit to the pilot.Defence Science Journal, 2013, 63(2, pp.129-130, DOI:http://dx.doi.org/10.14429/dsj.63.4269

  8. Bubble systems

    CERN Document Server

    Avdeev, Alexander A

    2016-01-01

    This monograph presents a systematic analysis of bubble system mathematics, using the mechanics of two-phase systems in non-equilibrium as the scope of analysis. The author introduces the thermodynamic foundations of bubble systems, ranging from the fundamental starting points to current research challenges. This book addresses a range of topics, including description methods of multi-phase systems, boundary and initial conditions as well as coupling requirements at the phase boundary. Moreover, it presents a detailed study of the basic problems of bubble dynamics in a liquid mass: growth (dynamically and thermally controlled), collapse, bubble pulsations, bubble rise and breakup. Special emphasis is placed on bubble dynamics in turbulent flows. The analysis results are used to write integral equations governing the rate of vapor generation (condensation) in non-equilibrium flows, thus creating a basis for solving a number of practical problems. This book is the first to present a comprehensive theory of boil...

  9. AEG System -

    Data.gov (United States)

    Department of Transportation — The AEG System is used to create, revise, approve, and distribute text of the AEGS and Flight Standard Board (FSB)/Type Rating Report. The MMEL specifies under what...

  10. Recommender Systems

    CERN Document Server

    Lü, Linyuan; Yeung, Chi Ho; Zhang, Yi-Cheng; Zhang, Zi-Ke; Zhou, Tao

    2012-01-01

    The ongoing rapid expansion of the Internet greatly increases the necessity of effective recommender systems for filtering the abundant information. Extensive research for recommender systems is conducted by a broad range of communities including social and computer scientists, physicists, and interdisciplinary researchers. Despite substantial theoretical and practical achievements, unification and comparison of different approaches are lacking, which impedes further advances. In this article, we review recent developments in recommender systems and discuss the major challenges. We compare and evaluate available algorithms and examine their roles in the future developments. In addition to algorithms, physical aspects are described to illustrate macroscopic behavior of recommender systems. Potential impacts and future directions are discussed. We emphasize that recommendation has a great scientific depth and combines diverse research fields which makes it of interests for physicists as well as interdisciplinar...

  11. Systems failure.

    OpenAIRE

    Macleod, Anna

    1998-01-01

    Systems Failure A solo exhibition of new work by Anna Macleod developed in conversation with curator Liz Burns. The Dock, Carrick on Shannon, Co Leitrim. Ireland. 12th February – 17th April 2010. The works for the exhibition Systems Failure include drawings, prints and small constructions that examine the delicate balance that exists between need and aspects of failure rooted in the relationship between humanity and land use. The work seeks to question the relationship between scient...

  12. Nanorobotic Systems

    Directory of Open Access Journals (Sweden)

    Lixin Dong

    2008-11-01

    Full Text Available Two strategies towards the realization of nanotechnology have been presented, i.e., top-down and bottom up. The former one is mainly based on nanofabrication and includes technologies such as nano-lithography, nano-imprint, and etching. Presently, they are still 2D fabrication processes with low resolution. The later one is an assembly-based technique. At present, it includes such items as self-assembly, dip-pen lithography, and directed self-assembly. These techniques can generate regular nano patterns in large scales. To fabricate 3D complex nano devices there are still no effective ways by so far. Here we show our effort on the development of a nano laboratory, a prototype nanomanufacturing system, based on nanorobotic manipulations. In which, we take a hybrid strategy as shown in Fig. 1. In this system, nano fabrication and nano assembly can be performed in an arbitrary order to construct nano building blocks and finally nano devices. The most important feature in this system is that the products can be fed back into the system to shrink the system part by part leading to nanorobots. Property characterization can be performed in each intermediate process. Due to the nanorobotic manipulation system, dynamic measurement can be performed rather than conventional static observations.

  13. System-of-Systems Complexity

    Directory of Open Access Journals (Sweden)

    Hermann Kopetz

    2013-11-01

    Full Text Available The global availability of communication services makes it possible to interconnect independently developed systems, called constituent systems, to provide new synergistic services and more efficient economic processes. The characteristics of these new Systems-of-Systems are qualitatively different from the classic monolithic systems. In the first part of this presentation we elaborate on these differences, particularly with respect to the autonomy of the constituent systems, to dependability, continuous evolution, and emergence. In the second part we look at a SoS from the point of view of cognitive complexity. Cognitive complexity is seen as a relation between a model of an SoS and the observer. In order to understand the behavior of a large SoS we have to generate models of adequate simplicity, i.e, of a cognitive complexity that can be handled by the limited capabilities of the human mind. We will discuss the importance of properly specifying and placing the relied-upon message interfaces between the constituent systems that form an open SoS and discuss simplification strategies that help to reduce the cognitive complexity.

  14. Systems Studies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  15. Systemic trauma.

    Science.gov (United States)

    Goldsmith, Rachel E; Martin, Christina Gamache; Smith, Carly Parnitzke

    2014-01-01

    Substantial theoretical, empirical, and clinical work examines trauma as it relates to individual victims and perpetrators. As trauma professionals, it is necessary to acknowledge facets of institutions, cultures, and communities that contribute to trauma and subsequent outcomes. Systemic trauma-contextual features of environments and institutions that give rise to trauma, maintain it, and impact posttraumatic responses-provides a framework for considering the full range of traumatic phenomena. The current issue of the Journal of Trauma & Dissociation is composed of articles that incorporate systemic approaches to trauma. This perspective extends conceptualizations of trauma to consider the influence of environments such as schools and universities, churches and other religious institutions, the military, workplace settings, hospitals, jails, and prisons; agencies and systems such as police, foster care, immigration, federal assistance, disaster management, and the media; conflicts involving war, torture, terrorism, and refugees; dynamics of racism, sexism, discrimination, bullying, and homophobia; and issues pertaining to conceptualizations, measurement, methodology, teaching, and intervention. Although it may be challenging to expand psychological and psychiatric paradigms of trauma, a systemic trauma perspective is necessary on both scientific and ethical grounds. Furthermore, a systemic trauma perspective reflects current approaches in the fields of global health, nursing, social work, and human rights. Empirical investigations and intervention science informed by this paradigm have the potential to advance scientific inquiry, lower the incidence of a broader range of traumatic experiences, and help to alleviate personal and societal suffering.

  16. Turbine system

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, Kevin Weston; Dillard, Daniel Jackson

    2016-05-03

    A turbine system is disclosed. The turbine system includes a transition duct having an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The turbine system further includes a turbine section connected to the transition duct. The turbine section includes a plurality of shroud blocks at least partially defining a hot gas path, a plurality of buckets at least partially disposed in the hot gas path, and a plurality of nozzles at least partially disposed in the hot gas path. At least one of a shroud block, a bucket, or a nozzle includes means for withstanding high temperatures.

  17. Cognitive Systems

    DEFF Research Database (Denmark)

    user models and user interaction models. Research in cognitive information processing is inherently multi-disciplinary and involves natural science and technical disciplines, e.g., control, automation, and robot research, physics and computer science, as well as humanities such as social sciences......The tutorial will discuss the definition of cognitive systems as the possibilities to extend the current systems engineering paradigm in order to perceive, learn, reason and interact robustly in open-ended changing environments. I will also address cognitive systems in a historical perspective...... and its relation and potential over current artificial intelligence architectures. Machine learning models that learn from data and previous knowledge will play an increasingly important role in all levels of cognition as large real world digital environments (such as the Internet) usually are too complex...

  18. Microbiology System

    Science.gov (United States)

    1992-01-01

    Technology originating in a NASA-sponsored study of the measurement of microbial growth in zero gravity led to the development of Biomerieux Vitek, Inc.'s VITEK system. VITEK provides a physician with accurate diagnostic information and identifies the most effective medication. Test cards are employed to identify organisms and determine susceptibility to antibiotics. A photo-optical scanner scans the card and monitors changes in the growth of cells contained within the card. There are two configurations - VITEK and VITEK JR as well as VIDAS, a companion system that detects bacteria, viruses, etc. from patient specimens. The company was originally created by McDonnell Douglas, the NASA contractor.

  19. Lubrication system

    Energy Technology Data Exchange (ETDEWEB)

    Wadding, C.; Lagasse, N.L.; Milo, G.T.; Vankamerik, J.G.

    1986-02-11

    This patent describes a lubrication system for controlling the flow of lubricant as a function of the altitude at which a gas turbine engine is operating. This lubrication system is comprised of: 1.) A source of lubricant under pressure; 2.) A unit requiring lubrication; 3.) A movable valve in fluid communication with the source and with the unit for regulating the flow of lubricant from the source to the unit; and 4.) An altitude sensor associated with the movable valve for positioning the movable valve to control the flow of lubricant from the source to the unit, as a function of the altitude at which the engine is operating.

  20. System Description:

    DEFF Research Database (Denmark)

    Schürmann, Carsten; Poswolsky, Adam

    2009-01-01

    Delphin is a functional programming language [Adam Poswolsky and Carsten Schürmann. Practical programming with higher-order encodings and dependent types. In European Symposium on Programming (ESOP), 2008] utilizing dependent higher-order datatypes. Delphin's two-level type-system cleanly separates...... data from computation, allowing for decidable type checking. The data level is LF [Robert Harper, Furio Honsell, and Gordon Plotkin. A framework for defining logics. Journal of the Association for Computing Machinery, 40(1):143-184, January 1993], which allows for the specification of deductive systems...

  1. [Systemic scleroderma].

    Science.gov (United States)

    Hunzelmann, N

    2013-04-01

    Systemic scleroderma is a chronic autoimmune disease affecting the skin, internal organs and the musculoskeletal system. The presence of Raynaud phenomenon, anti-nuclear antibodies and pathologic capillaroscopy are early signs of the disease. Limited cutaneous SSc, diffuse cutaneous SSc and SSc-overlap syndromes are the main clinical subtypes. Multidisciplinary care is mandatory. Follow-up examinations should be performed at least annually in order to recognize in a timely fashion treatable organ involvement such as pulmonary arterial hypertension. Besides symptomatic treatment of organ involvement, immunosuppressive therapy is indicated for a progressive inflammatory course.

  2. Computer systems

    Science.gov (United States)

    Olsen, Lola

    1992-01-01

    In addition to the discussions, Ocean Climate Data Workshop hosts gave participants an opportunity to hear about, see, and test for themselves some of the latest computer tools now available for those studying climate change and the oceans. Six speakers described computer systems and their functions. The introductory talks were followed by demonstrations to small groups of participants and some opportunities for participants to get hands-on experience. After this familiarization period, attendees were invited to return during the course of the Workshop and have one-on-one discussions and further hands-on experience with these systems. Brief summaries or abstracts of introductory presentations are addressed.

  3. Systems chemistry

    NARCIS (Netherlands)

    Ludlow, R. Frederick; Otto, Sijbren

    2008-01-01

    The study of complex mixtures of interacting synthetic molecules has historically not received much attention from chemists, even though research into complexity is well established in the neighbouring fields. However, with the huge recent interest in systems biology and the availability of modern a

  4. Solar system

    CERN Document Server

    Homer, Charlene

    2007-01-01

    Thrill young astronomers with a journey through our Solar System. Find out all about the Inner and Outer Planets, the Moon, Stars, Constellations, Asteroids, Meteors and Comets. Using simplified language and vocabulary, concepts such as planetary orbits, the asteroid belt, the lunar cycle and phases of the moon, and shooting stars are all explored.

  5. Transport system

    NARCIS (Netherlands)

    Drenth, K.F.

    1999-01-01

    The transport system comprises at least one road surface (2) and at least one vehicle (4) on wheels (6). The road surface (2) has a substantially bowl-shaped cross section and the vehicle (4) is designed so that the wheels (6) run directly on the road surface (2) while the road surface (2) acts as a

  6. Immune System

    Science.gov (United States)

    ... and mature there to become B cells or leave for the thymus gland, where they mature to become T cells. B lymphocytes and T lymphocytes have separate jobs to do: B lymphocytes are like the body's military intelligence system, seeking out their targets and sending defenses to ...

  7. System Dynamics

    Science.gov (United States)

    Morecroft, John

    System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management. It looks at feedback loops and time delays that affect system behaviour in a non-linear way, and illustrates how dynamic behaviour depends upon feedback loop structures. It also recognises improvements as part of the ongoing process of managing a situation in order to achieve goals. Significantly it recognises the importance of context, and practitioner skills. Feedback systems thinking views problems and solutions as being intertwined. The main concepts and tools: feedback structure and behaviour, causal loop diagrams, dynamics, are practically illustrated in a wide variety of contexts from a hot water shower through to a symphony orchestra and the practical application of the approach is described through several real examples of its use for strategic planning and evaluation.

  8. Irrigation System

    Science.gov (United States)

    1984-01-01

    Under contract with Marshall Space Flight Center, Midwest Research Institute compiled a Lubrication Handbook intended as a reference source for designers and manufacturers of aerospace hardware and crews responsible for maintenance of such equipment. Engineers of Lindsay Manufacturing Company learned of this handbook through NASA Tech Briefs and used it for supplemental information in redesigning gear boxes for their center pivot agricultural irrigation system.

  9. Immune System

    Science.gov (United States)

    A properly functioning immune system is essential to good health. It defends the body against infectious agents and in some cases tumor cells. Individuals with immune deficiencies resulting from genetic defects, diseases (e.g., AIDS, leukemia), or drug therapies are more suscepti...

  10. [Systemic sclerosis].

    Science.gov (United States)

    Schinke, Susanne; Riemekasten, Gabriela

    2016-04-01

    Systemic sclerosis is a challenging and heterogeneous disease due to the involvement of multiple organs and the high impact on morbidity and quality of life. Lung fibrosis, pulmonary arterial hypertension, and cardiac manifestations are main causes of systemic sclerosis-related deaths. In addition, patients suffer from a various range of co-morbidities such as malnutrition, depression, osteoporosis, malignancies, which are increased in these patients and have to be identified and treated. Early assessment of organ damage is a key to therapeutic success. The discovery of pathogenic autoantibodies combined with increased evidence of effective immunosuppressive and vasoactive treatment strategies are major developments in the therapy of the disease. At present, several clinical studies are ongoing and some of the biological therapies are promising.

  11. Blackboard Systems.

    Science.gov (United States)

    1986-06-01

    article stated that although the importance of context, syntax, semantics, and phonological rules in the recognition of speech was accepted, no system had...of, from the lowest to the highest level: parametric, segmental, phonetic , phonemic, syllabic, lexical, phrasal, and conceptual levels (see Figure 3...from classification (classifying acoustic segments into phonetic classes), to recognition (recognizing words) to generation and 42SCe (25] for a

  12. Security system

    Science.gov (United States)

    Baumann, Mark J.; Kuca, Michal; Aragon, Mona L.

    2016-02-02

    A security system includes a structure having a structural surface. The structure is sized to contain an asset therein and configured to provide a forceful breaching delay. The structure has an opening formed therein to permit predetermined access to the asset contained within the structure. The structure includes intrusion detection features within or associated with the structure that are activated in response to at least a partial breach of the structure.

  13. Imaging System

    Science.gov (United States)

    1995-01-01

    The 1100C Virtual Window is based on technology developed under NASA Small Business Innovation (SBIR) contracts to Ames Research Center. For example, under one contract Dimension Technologies, Inc. developed a large autostereoscopic display for scientific visualization applications. The Virtual Window employs an innovative illumination system to deliver the depth and color of true 3D imaging. Its applications include surgery and Magnetic Resonance Imaging scans, viewing for teleoperated robots, training, and in aviation cockpit displays.

  14. Propulsion Systems

    Science.gov (United States)

    2011-03-31

    definition we are choosing x to be aligned with the direction of flight. Thus, accounting for the possible rotation of the axes, the acceleration in...Monopropellants. In a monopropellant system, like the name suggests, there is one propellant which decomposes exothermically as it passes through a catalytic...it comes into contact with the catalyst bed. Subsequently, the ammonia decomposes into nitrogen and hydrogen in an endothermic reaction lowering the

  15. Law system and legislation system

    OpenAIRE

    Boshno, Svetlana

    2013-01-01

    This paper is a continuation of publication of the «Jurisprudence» textbook by Svetlana Vladimirovna Boshno. Law system is a key element of general theory of law. The major fundamentals of its construction are subject matter and method of legal regulation. Of great importance is the division of legal regulation methods into mandative and dispositive ones. The paper articulates the concepts of institute and branch of law demonstrated through various examples. An important classification of bra...

  16. Linear systems

    CERN Document Server

    Bourlès, Henri

    2013-01-01

    Linear systems have all the necessary elements (modeling, identification, analysis and control), from an educational point of view, to help us understand the discipline of automation and apply it efficiently. This book is progressive and organized in such a way that different levels of readership are possible. It is addressed both to beginners and those with a good understanding of automation wishing to enhance their knowledge on the subject. The theory is rigorously developed and illustrated by numerous examples which can be reproduced with the help of appropriate computation software. 60 exe

  17. Nuclear systems

    CERN Document Server

    Todreas, Neil E

    2011-01-01

    Principal Characteristics of Power ReactorsIntroductionPower CyclesPrimary Coolant SystemsReactor CoresFuel AssembliesAdvanced Water- and Gas-Cooled Reactors (Generation III And III+)Advanced Thermal and Fast Neutron Spectrum Reactors (Generation IV)ReferencesProblemsThermal Design Principles and ApplicationIntroductionOverall Plant Characteristics Influenced by Thermal Hydraulic ConsiderationsEnergy Production and Transfer ParametersThermal Design LimitsThermal Design MarginFigures of Merit for Core Thermal PerformanceThe Inverted Fuel ArrayThe Equivalent Annulus ApproximationReferencesProble

  18. Expert Systems: What Is an Expert System?

    Science.gov (United States)

    Duval, Beverly K.; Main, Linda

    1994-01-01

    Describes expert systems and discusses their use in libraries. Highlights include parts of an expert system; expert system shells; an example of how to build an expert system; a bibliography of 34 sources of information on expert systems in libraries; and a list of 10 expert system shells used in libraries. (Contains five references.) (LRW)

  19. Systemic Planning

    DEFF Research Database (Denmark)

    Leleur, Steen

    This book presents principles and methodology for planning in a complex world. It sets out a so-called systemic approach to planning, among other things, by applying “hard” and “soft” methodologies and methods in combination. The book is written for Ph.D and graduate students in engineering......, business and other fields, and it is useful for all professionals, across a wide range of employment areas, who share an interest in renewing planning practice. Such an endeavour is seen as both important and timely, recognising that many complex planning tasks necessitate organisations – be they public...... or private – to engage in planning to prepare proactive decision-making....

  20. Model Systems

    Directory of Open Access Journals (Sweden)

    Francisco Rodríguez-Trelles

    1998-12-01

    Full Text Available Current efforts to study the biological effects of global change have focused on ecological responses, particularly shifts in species ranges. Mostly ignored are microevolutionary changes. Genetic changes may be at least as important as ecological ones in determining species' responses. In addition, such changes may be a sensitive indicator of global changes that will provide different information than that provided by range shifts. We discuss potential candidate systems to use in such monitoring programs. Studies of Drosophila subobscura suggest that its chromosomal inversion polymorphisms are responding to global warming. Drosophila inversion polymorphisms can be useful indicators of the effects of climate change on populations and ecosystems. Other species also hold the potential to become important indicators of global change. Such studies might significantly influence ecosystem conservation policies and research priorities.

  1. Turbocompound system

    Energy Technology Data Exchange (ETDEWEB)

    Fox, L.D.

    1986-05-06

    A turbocompound system is described for improving the performance of an internal combustion engine without substantially increasing an end viewed profile of the engine to which it is mounted in use. The system consists of: (a) an exhaust driven turbocharger means having an exhaust manifold means extending in an axial direction for collecting exhaust gases from engine cylinders and delivering the gases to an outlet end thereof, exhaust turbine means for extracting energy from the exhaust gases, the exhaust turbine means being provided with an inlet connected to the outlet end of the manifold and an outlet for discharging the exhaust gases, compressor means coupled to the exhaust turbine means for providing a supply of charge air under pressure to an air outlet thereof for delivery to air intake means of an internal combustion engine in use; (b) a power turbine means for extracting additional energy from the exhaust gases, the power turbine means having an intake connected to the outlet of the exhaust turbine means, and mounting means on a side of the power turbine means facing in a direction parallel to the axial direction of the exhaust manifold means that is constructed for being mounted, in use, on an end of an engine adjacent one end of a crankshaft of the engine; and (c) coupling means connected to the power turbine means for transferring mechanical energy produced by the power turbine means, the coupling means extending from the power turbine means to a power take-off end in a direction parallel to the axial length of the exhaust manifold means by an amount that is sufficient for enabling the power take-off end to be connected, in use, to an opposite end of the engine crankshaft from the one end thereof in a manner for transferring the mechanical energy produced by the power turbine means adjacent the one end of the crankshaft to the opposite end of the crankshaft without having to pass therethrough.

  2. Systems engineering simplified

    CERN Document Server

    Cloutier, Robert; Bone, Mary Alice

    2015-01-01

    IntroductionOverviewDiscussion of Common TerminologyThe Case for Systems EngineeringA Brief History of Systems EngineeringSystem ExamplesSummaryThe System Life CycleManaging System Development-The Vee ModelSystem ProductionSystem Utilization and SupportSystem Retirement and DisposalOther Systems Engineering Development ModelsSpiral ModelAgile Model for Systems EngineeringSystem of InterestAbstraction and DecompositionIntegrationDeveloping and Managing RequirementsCyclone Requiremen

  3. Cardiovascular System

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    7.1 Heart failure2007175 Effects of recombinant human brain natriuretic peptide on aldosterone and endothelin-1 in treatment of heart failure. FU Yao(付尧),et al. Dept Cardiol, 1st Affili Hosp, China Med Univ, Shenyang 110001. Chin Cir J 2007;22(1):35-37. Obiective To study the efficacy and the effects of recombinant human brain natriuretic peptide(rhBNP) on aldosterone and endothelin-1 in the treatment of congestive heart failure(CHF).Methods A randomized, open, controlled clinical trial was conducted in 35 patients with CHF. Eighteen received rhBNP and 17 were treated with nitroglycerin as controls. The changes hemodynamic indexes, the plasma concentrations of K+, Na+, aldo-sterone(ALD) and endothelin-1 (ET-1) in order to examine the efficacy and mechanism of rhBNP. Results Between experiment and control groups significant differences were found in the decreasing of PCWP, PAP and plasma concentration of Na+, ALD, ET-1, and in the increasing of plasma concentration of K+ (P<0.05~0.01). Conclusion The mechanism of rhBNP may be associated with the overactivation of renin-angiotension-aldosterone system, and the inhibited production of endothelin-1.

  4. System safety education focused on system management

    Science.gov (United States)

    Grose, V. L.

    1971-01-01

    System safety is defined and characteristics of the system are outlined. Some of the principle characteristics include role of humans in hazard analysis, clear language for input and output, system interdependence, self containment, and parallel analysis of elements.

  5. Respiratory System

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    8.1 Respiratory failure2007204 Comparison of the effects of BiPAP ventilation combined with lung recruitment maneuvers and low tidal volume A/C ventilation in patients with acute respiratory distress syndrome. WANG Xiaozhi(王晓芝),et al. Dept Respir & Intensive Care Unit, Binzhou Med Coll, Binzhou 256603. Chin J Tuberc Respir Dis 2007;30(1):44-47. Objective To compare the effects of BiPAP ventilation combined with lung recruitment maneuvers(LRM) with low tidal volume A/C ventilation in patients with acute respiratory distress syndrome (ARDS). Methods A prospective, randomized comparison of BiPAP mechanical ventilation combined with lung recruitment maneuvers(test group) with low tidal volume A/C ventilation (control group) was conducted in 28 patients with ARDS. FiO2/PaO2 ratio, respiratory system compliance(Cs), central venous pressure (CVP), duration of ventilation support were recorded at 0 h, 48 h and 72 h separately. The ventilation associated lung injury and mortality at 28 d were also recorded. Results The FiO2/PaO2 ratio were (298±16) and (309±16) cm H2O, Cs were (38.4±2.2) and (42.0±1.3) ml/cm H2O, CVP were (13.8±0.8) and (11.6±0.7) cm H2O in the test group at 48 h and 72 h separately. In the control group, FiO2/PaO2 ratio were (212±12) and (246±17) cm H2O, Cs were (29.5±1.3) and (29.0±1.0) ml/cm H2O, CVP were 18.6±1.1 and (16.8±1.0) cm H2O. The results were better in the test group as compared with the control group (t=10.03-29. 68, all P<0.01). The duration of ventilation support in the test group was shorter than the control group [(14±3) d vs (19±3)d, t=4.80, P<0.01]. The mortality in 28 d and ventilation associated lung injury were similar in the two groups. Conclusion The results show that combination of LRM with BiPAP mode ventilation, as compared with the control group, contributes to the improved FiO2/PaO2 ratio, pulmonary compliance, stable homodynamic and shorter duration of ventilation support in patients with ARDs.

  6. Quality management system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mu Sung

    2009-08-15

    This book deals with ISO9001 quality management system which includes summary of this system such as classification of quality, principle of quality management, and definition, requirement and procedure of quality management system, introduction of ISO9001 system like model of ISO9001 quality management system, ISO certificate system, structure of ISO9001 standard, requirement of ISO9001 quality management system, process approach and documentation of system, propel cases of ISO9001 quality management system.

  7. Square conservation systems and Hamiltonian systems

    Institute of Scientific and Technical Information of China (English)

    王斌; 曾庆存; 季仲贞

    1995-01-01

    The internal and external relationships between the square conservation scheme and the symplectic scheme are revealed by a careful study on the interrelation between the square conservation system and the Hamiltonian system in the linear situation, thus laying a theoretical basis for the application and extension of symplectic schemes to square conservations systems, and of those schemes with quadratic conservation properties to Hamiltonian systems.

  8. Systems theory of interconnected port contact systems

    NARCIS (Netherlands)

    Eberard, D.; Maschke, B.M.; Schaft, A.J. van der

    2005-01-01

    Port-based network modeling of a large class of complex physical systems leads to dynamical systems known as port-Hamiltonian systems. The key ingredient of any port-Hamiltonian system is a power-conserving interconnection structure (mathematically formalized by the geometric notion of a Dirac struc

  9. Protecting Information in Systems of Systems

    NARCIS (Netherlands)

    Trivellato, Daniel; Zannone, Nicola; Etalle, Sandro

    2011-01-01

    Systems of Systems (SoS) are dynamic, distributed coalitions of autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, the SoS paradigm has a strong impact on system interoperability and on the securi

  10. Visceral perception: sensory transduction in visceral afferents and nutrients.

    Science.gov (United States)

    Raybould, H E

    2002-07-01

    The possible mechanisms that may be involved in nutrient detection in the wall of the gastrointestinal tract are reviewed. There is strong functional and electrophysiological evidence that both intrinsic and extrinsic primary afferent neurones mediate mechano- and chemosensitive responses in the gastrointestinal tract. This review focuses on the extrinsic afferent pathways as these are the ones that convey information to the central nervous system which is clearly necessary for perception to occur.

  11. Understanding Patterns for System of Systems Integration

    DEFF Research Database (Denmark)

    Kazman, Rick; Schmid, Klaus; Nielsen, Claus Ballegård

    2013-01-01

    of systems integration patterns. These characteristics at the same time support the architecting process by highlighting important issues a SoS architect needs to consider. We discuss the consolidated template and illustrate it with an example pattern. We also discuss the integration of this novel pattern......Architecting systems of systems is well known to be a formidable challenge. A major aspect in this is defining the integration among the systems that constitute the system of systems. In this paper, we aim to support the SoS architect by systematically developing a way to characterize system...

  12. Concept and System of Personification Control System

    Institute of Scientific and Technical Information of China (English)

    Bai,Fengshuang; Yin,Yixin; Tu,Xuyan; Zhang,Ying

    2006-01-01

    This paper provides the system and conception of the Personification Control System (PCS) on the basis of Intelligent Control System based on Artificial life (ICS/AL), Artificial Emotion, Humanoid Control, and Intelligent Control System based on Field bus. According to system science and deciding of organize of biology, the Pyramid System of PCS are created. Then Pyramid System of PCS which is made up of PCS1/H, PCS1/S, PCS1/O, PCS1/C and PCS1/G is described.

  13. Networked control of microgrid system of systems

    Science.gov (United States)

    Mahmoud, Magdi S.; Rahman, Mohamed Saif Ur; AL-Sunni, Fouad M.

    2016-08-01

    The microgrid has made its mark in distributed generation and has attracted widespread research. However, microgrid is a complex system which needs to be viewed from an intelligent system of systems perspective. In this paper, a network control system of systems is designed for the islanded microgrid system consisting of three distributed generation units as three subsystems supplying a load. The controller stabilises the microgrid system in the presence of communication infractions such as packet dropouts and delays. Simulation results are included to elucidate the effectiveness of the proposed control strategy.

  14. D0 Cryo System Control System Autodialer

    Energy Technology Data Exchange (ETDEWEB)

    Urbin, J.; /Fermilab

    1990-04-17

    The DO cryogenic system is controlled by a TI565-PLC based control system. This allows the system to be unmanned when in steady state operation. System experts will need to be contacted when system parameters exceed normal operating points and reach alarm setpoints. The labwide FIRUS system provides one alarm monitor and communication link. An autodialer provides a second and more flexible alarm monitor and communication link. The autodialer monitors contact points in the control system and after receiving indication of an alarm accesses a list of experts which it calls until it receives an acknowledgement. There are several manufacturers and distributors of autodialer systems. This EN explains the search process the DO cryo group used to fmd an autodialer system that fit the cryo system's needs and includes information and specs for the unit we chose.

  15. Freshwater systems; Frisch gezapft

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.P.

    2008-06-09

    Increasingly, providers of solar systems are also offering freshwater systems, although these are more costly than combined storage systems. The contribution discusses the pros and cons of these systems as well as the freshwater quality. (orig.)

  16. Integrated library systems.

    Science.gov (United States)

    Goldstein, C M

    1983-07-01

    The development of integrated library systems is discussed. The four major discussion points are (1) initial efforts; (2) network resources; (3) minicomputer-based systems; and (4) beyond library automation. Four existing systems are cited as examples of current systems.

  17. System design specification Brayton Isotope Power System (BIPS) Flight System (FS), and Ground Demonstration System (GDS)

    Energy Technology Data Exchange (ETDEWEB)

    1976-06-14

    The system design specification for ground demonstration, development, and flight qualification of a Brayton Isotope Power System (BIPS) is presented. The requirements for both a BIPS conceptual Flight System (FS) and a Ground Demonstration System (GDS) are defined.

  18. Apigenin suppresses GLUT-1 and p-AKT expression to enhance the chemosensitivity to cisplatin of laryngeal carcinoma Hep-2 cells: an in vitro study.

    Science.gov (United States)

    Xu, Ying-Ying; Wu, Ting-Ting; Zhou, Shui-Hong; Bao, Yang-Yang; Wang, Qin-Ying; Fan, Jun; Huang, Ya-Ping

    2014-01-01

    Glucose transporter-1 (GLUT-1) and PI3K/Akt are known to be closely involved in resistance to chemotherapy. Co-targeted therapy reducing GLUT-1 expression and PI3K/Akt pathway activity may overcome the chemoresistance of human cancers. Apigenin may inhibit the expression of GLUT-1 and the PI3K/Akt pathway. We hypothesized that over-expression of GLUT-1 and p-Akt was associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. We explored whether apigenin inhibited GLUT-1 and p-Akt, resulting in sensitization of laryngeal carcinoma Hep-2 cells to cisplatin. Real-time RT-PCR and Western blotting confirmed the presence of GLUT-1 mRNA, and GLUT-1 and p-Akt proteins in Hep-2 cells. We found that resistance or insensitivity of Hep-2 cells to cisplatin might be associated with such expression. Apigenin markedly enhanced the cisplatin-induced suppression of Hep-2 cell growth. This effect was concentration- and time-dependent. Thus apigenin may significantly reduce the levels of GLUT-1 mRNA, and GLUT-1 and p-Akt proteins, in cisplatin-treated Hep-2 cells, in a concentration- and time-dependent manner. To conclude, overexpression of GLUT-1 mRNA may be associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. Apigenin may enhance the sensitivity to cisplatin of laryngeal carcinoma cells via inhibition of GLUT-1 and p-Akt expression.

  19. Chemo-sensitivity in a panel of B-cell precursor acute lymphoblastic leukemia cell lines, YCUB series, derived from children.

    Science.gov (United States)

    Goto, Hiroaki; Naruto, Takuya; Tanoshima, Reo; Kato, Hiromi; Yokosuka, Tomoko; Yanagimachi, Masakatsu; Fujii, Hisaki; Yokota, Shumpei; Komine, Hiromi

    2009-10-01

    Sensitivity to 10 anticancer drugs was evaluated in 6 childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cell lines. Authenticity of newly established cell lines was confirmed by genomic fingerprinting. The line YCUB-5R established at relapse was more resistant to 4-hydroperoxy-cyclophosphamide, cytarabine, L-asparaginase, topotecan, fludarabine, and etoposide than YCUB-5 from the same patient at diagnosis. Of the drugs tested, etoposide and SN-38 (irinotecan) showed highest efficacy in the panel, with 50% growth inhibition at 0.22-1.8 microg/ml and 0.57-3.6 ng/ml, respectively. This cell line panel offers an in vitro model for the development of new therapies for childhood BCP-ALL.

  20. Inhibition of nuclear factor-κB activity enhanced chemosensitivity to cisplatin in human lung adeno-carcinoma A549 cells under chemical hypoxia conditions

    Institute of Scientific and Technical Information of China (English)

    LI Fang; HUANG Li; SU Xiao-li; GU Qi-hua; HU Cheng-ping

    2013-01-01

    Background Tumor hypoxia,one of the features of solid tumors,is associated with chemo-resistance.Recently,nuclear factor-KB (NF-kB) was found to be activated during hypoxia.However,the impact of NF-kB activation on chemo-resistance during hypoxia remains unknown.Methods Human lung adenocarcinoma A549 cells were transfected with NF-kB p65siRNA and treated with cobalt chloride (CoCl2) to mimic hypoxia in the presence or absence of cisplatin.NF-kB expression was measured by Western blotting,immune-fluorescence and real-time PCR.Hypoxia-inducible factor-1α (HIF-1α) and Bcl-2 expression were determined by Western blotting.Cell apoptosis and survival with half-maximum inhibitory concentration (IC50) of cisplatin were determined by Annexin V-FITC/PI and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT),respectively.Results Exposure ofA549 cells to CoCl2 increased nuclear HIF-1α protein expression,and enhanced NF-kB p65 protein nuclear accumulation (the mark of NF-kB activation) in a time and dose dependant manner.CoCl2 did not promote apoptosis in A549 cells; on the contrary,it reduced cisplatin-induced apoptosis and increased the IC50 of cisplatin.However,when we inhibited CoCl2-induced activation of NF-kB through NF-kB p65siRNA,cisplatin-induced apoptosis was increased and IC50 of cisplatin was reduced to levels similar to those in control cells.Meanwhile,CoCl2-induced Bcl-2 overexpression was down-regulated in the presence of cisplatin when NF-KB activity was inhibited.Conclusion Up-regulating Bcl-2 might be involved in NF-kB activation induced resistance to cisplatin in A549 cells under CoCl2-induced chemical hypoxia.

  1. Immunohistochemical expression of stem cell, endothelial cell, and chemosensitivity markers in primary glioma spheroids cultured in serum-containing and serum-free medium

    DEFF Research Database (Denmark)

    Christensen, Karina; Aaberg-Jessen, Charlotte; Andersen, Claus;

    2010-01-01

    To investigate the influence of serum-free medium (SFM) supplemented with epidermal growth factor and basic fibroblast growth factor compared with conventional serum-containing medium (SCM) on the phenotype of organotypic primary spheroids from seven gliomas....

  2. Statins augment the chemosensitivity of colorectal cancer cells inducing epigenetic reprogramming and reducing colorectal cancer cell 'stemness' via the bone morphogenetic protein pathway

    NARCIS (Netherlands)

    Kodach, L.L.; Jacobs, R.J.; Voorneveld, P.W.; Wildenberg, M.E.; Verspaget, H.W.; van Wezel, T.; Morreau, H.; Hommes, D.W.; Peppelenbosch, M.P.; van den Brink, G.R.; Hardwick, J.C.H.

    2011-01-01

    Promoter hypermethylation is an important and potentially reversible mechanism of tumour suppressor gene silencing in cancer. Compounds that demethylate tumour suppressor genes and induce differentiation of cancer cells, but do not have toxic side effects, would represent an exciting option in cance

  3. TAp73-mediated the activation of c-Jun N-terminal kinase enhances cellular chemosensitivity to cisplatin in ovarian cancer cells.

    Directory of Open Access Journals (Sweden)

    Pingde Zhang

    Full Text Available P73, one member of the tumor suppressor p53 family, shares highly structural and functional similarity to p53. Like p53, the transcriptionally active TAp73 can mediate cellular response to chemotherapeutic agents in human cancer cells by up-regulating the expressions of its pro-apoptotic target genes such as PUMA, Bax, NOXA. Here, we demonstrated a novel molecular mechanism for TAp73-mediated apoptosis in response to cisplatin in ovarian cancer cells, and that was irrespective of p53 status. We found that TAp73 acted as an activator of the c-Jun N-terminal kinase (JNK signaling pathway by up-regulating the expression of its target growth arrest and DNA-damage-inducible protein GADD45 alpha (GADD45α and subsequently activating mitogen-activated protein kinase kinase-4 (MKK4. Inhibition of JNK activity by a specific inhibitor or small interfering RNA (siRNA significantly abrogated TAp73-mediated apoptosis induced by cisplatin. Furthermore, inhibition of GADD45α by siRNA inactivated MKK4/JNK activities and also blocked TAp73-mediated apoptosis induction by cisplatin. Our study has demonstrated that TAp73 activated the JNK apoptotic signaling pathway in response to cisplatin in ovarian cancer cells.

  4. Distinct subpopulations of head and neck cancer cells with different levels of intracellular reactive oxygen species exhibit diverse stemness, proliferation, and chemosensitivity.

    Science.gov (United States)

    Chang, Ching-Wen; Chen, Yu-Syuan; Chou, Shiu-Huey; Han, Chia-Li; Chen, Yu-Ju; Yang, Cheng-Chieh; Huang, Chih-Yang; Lo, Jeng-Fan

    2014-11-01

    Head and neck squamous cell carcinoma (HNSCC) is driven by cancer-initiating cells (CIC), but their maintenance mechanisms are obscure. For hematopoietic stem cells, low levels of intracellular reactive oxygen species (ROS(Low)) is known to help sustain stemness properties. In this report, we evaluated the hypothesis that ROS(Low) character conferred CIC properties in HNSCC. Sphere cultures define CIC in HNSCC cell populations (HN-CIC). We found that ROS(Low) cells in HN-CIC defined in this manner were more numerous than in parental HNSCC cells. Further, ROS(Low) cells frequently coexpressed CIC surface markers such as memGrp78 and Glut3. Exploiting flow cytometry to sort cells on the basis of their ROS level, we found that isolated ROS(Low) cells displayed relatively more CIC properties, including quiescence, chemoresistance, in vitro malignant properties, and tumorigenicity. Pharmacological depletion of ROS modulators in cisplatin-treated HN-CIC reduced CIC properties, enhancing cell differentiation and enhancing cisplatin-induced cell death. Overall, our work defined cell subpopulations in HNSCC on the basis of differential intracellular ROS levels, which associated with stemness and chemoresistance properties. On the basis of our findings, we suggest that strategies to promote intracellular ROS levels may heighten the efficacy of conventional chemotherapy used for HNSCC treatment.

  5. Imidazolidine-4-one derivatives in the search for novel chemosensitizers of Staphylococcus aureus MRSA: synthesis, biological evaluation and molecular modeling studies.

    Science.gov (United States)

    Matys, Anna; Podlewska, Sabina; Witek, Karolina; Witek, Jagna; Bojarski, Andrzej J; Schabikowski, Jakub; Otrębska-Machaj, Ewa; Latacz, Gniewomir; Szymańska, Ewa; Kieć-Kononowicz, Katarzyna; Molnar, Joseph; Amaral, Leonard; Handzlik, Jadwiga

    2015-08-28

    A series of amine derivatives of 5-aromatic imidazolidine-4-ones (7-19), representing three subgroups: piperazine derivatives of 5-arylideneimidazolones (7-13), piperazine derivatives of 5-arylideneimidazolidine-2,4-dione (14-16) and primary amines of 5-naphthyl-5-methylimidazolidine-2,4-diones (17-19), was evaluated for their ability to improve antibiotics effectiveness in two strains of Gram-positive Staphylococcus aureus: ATCC 25923 (a reference strain) and MRSA (methicillin resistant S. aureus) HEMSA 5 (a resistant clinical isolate). The latter compounds (17-19) were obtained by 4-step synthesis using Bucherer-Bergs condensation, two-phase bromoalkylation and Gabriel reactions. The naphthalen derivative: (Z)-5-(naphthalen-2-ylmethylene)-2-(piperazin-1-yl)-3H-imidazol-4(5H)-one (10) was the most potent in combination with β-lactam antibiotics and ciprofloxacin against the resistant strain. The high potency to increase efficacy of oxacillin was noted for (Z)-5-(anthracen-10-ylmethylene)-2-(piperazin-1-yl)-3H-imidazol-4(5H)one (12) too. In order to explain the mechanism of action of the compounds 10 and 12, docking studies with the use of crystal structures of a penicillin binding protein (PBP2a) and MecR1 were carried out. Their outcomes suggested that the most probable mechanism of action of the active compounds is the interaction with MecR1. Molecular dynamic experiments performed for the active compounds and compound 13 (structurally similar to 12) supported this hypothesis and provided possible explanation of activity dependencies of the tested compounds in terms of the restoration of antibiotic efficacy in S. aureus MRSA HEMSA 5.

  6. Silencing of High Mobility Group Isoform I-C (HMGI-C) Enhances Paclitaxel Chemosensitivity in Breast Adenocarcinoma Cells (MDA-MB-468)

    Science.gov (United States)

    Mansoori, Behzad; Mohammadi, Ali; Goldar, Samira; shanehbandi, Dariush; Mohammadnejad, Leila; Baghbani, Elham; Kazemi, Tohid; Kachalaki, Saeed; Baradaran, Behzad

    2016-01-01

    Purpose: HMGI-C (High Mobility Group protein Isoform I-C) protein is a member of the high-mobility group AT-hook (HMGA) family of small non-histone chromosomal protein that can modulate transcription of an ample number of genes. Genome-wide studies revealed up regulation of the HMGI-C gene in many human cancers. We suggested that HMGI-C might play a critical role in the progression and migration of various tumors. However, the exact role of HMGI-C in breast adenocarcinoma has not been cleared. Methods: The cells were transfected with siRNAs using transfection reagent. Relative HMGI-C mRNA and protein levels were measured by quantitative real-time PCR and Western blotting, respectively. The cytotoxic effects of HMGI-C siRNA, Paclitaxel alone and combination on breast adenocarcinoma cells were determined using MTT assay. The migration after treatment by HMGI-C siRNA, Paclitaxel alone and combination were detected by wound-healing respectively. Results: HMGI-C siRNA significantly reduced both mRNA and protein expression levels in a 48 hours after transfection and dose dependent manner. We observed that the knockdown of HMGI-C led to the significant reduced cell viability and inhibited cells migration in MDA-MB-468 cells in vitro. Conclusion: These results propose that HMGI-C silencing and Paclitaxel treatment alone can inhibit the proliferation and migration significantly, furthermore, synergic effect of HMGI-C siRNA and Paclitaxel showed higher inhibition compared to mono treatment. Taken together, HMGI-C could be used as a promising therapeutic agent in the treatment of human breast adenocarcinoma. Therefore HMGI-C siRNA may be an effective adjuvant in human breast adenocarcinoma. PMID:27478778

  7. Regulation of death induction and chemosensitizing action of 3-bromopyruvate in myeloid leukemia cells: energy depletion, oxidative stress, and protein kinase activity modulation.

    Science.gov (United States)

    Calviño, Eva; Estañ, María Cristina; Sánchez-Martín, Carlos; Brea, Rocío; de Blas, Elena; Boyano-Adánez, María del Carmen; Rial, Eduardo; Aller, Patricio

    2014-02-01

    3-Bromopyruvate (3-BrP) is an alkylating, energy-depleting drug that is of interest in antitumor therapies, although the mechanisms underlying its cytotoxicity are ill-defined. We show here that 3-BrP causes concentration-dependent cell death of HL60 and other human myeloid leukemia cells, inducing both apoptosis and necrosis at 20-30 μM and a pure necrotic response at 60 μM. Low concentrations of 3-BrP (10-20 μM) brought about a rapid inhibition of glycolysis, which at higher concentrations was followed by the inhibition of mitochondrial respiration. The combination of these effects causes concentration-dependent ATP depletion, although this cannot explain the lethality at intermediate 3-BrP concentrations (20-30 μM). The oxidative stress caused by exposure to 3-BrP was evident as a moderate overproduction of reactive oxygen species and a concentration-dependent depletion of glutathione, which was an important determinant of 3-BrP toxicity. In addition, 3-BrP caused glutathione-dependent stimulation of p38 mitogen-activated protein kinase (MAPK), mitogen-induced extracellular kinase (MEK)/extracellular signal-regulated kinase (ERK), and protein kinase B (Akt)/mammalian target of rapamycin/p70S6K phosphorylation or activation, as well as rapid LKB-1/AMP kinase (AMPK) activation, which was later followed by Akt-mediated inactivation. Experiments with pharmacological inhibitors revealed that p38 MAPK activation enhances 3-BrP toxicity, which is conversely restrained by ERK and Akt activity. Finally, 3-BrP was seen to cooperate with antitumor agents like arsenic trioxide and curcumin in causing cell death, a response apparently mediated by both the generation of oxidative stress induced by 3-BrP and the attenuation of Akt and ERK activation by curcumin. In summary, 3-BrP cytotoxicity is the result of several combined regulatory mechanisms that might represent important targets to improve therapeutic efficacy.

  8. Identification of the Microtubule Inhibitor-Activated Bcl-xL Kinase: A Regulator of Breast Cancer Cell Chemosensitivity to Taxol

    Science.gov (United States)

    2010-10-31

    differentiation: biochemical identification using Xenopus egg extracts. Proc. Natl. Acad. Sci. U. S. A. 96:4797–4802. 5 7. Vassilev, L. T., C. Tovar ...L. T., C. Tovar , S. Chen, D. Knezevic, X. Zhao, H. Sun, D. C. Heimbrook, and L. Chen. 2006. Selective small-molecule inhibitor reveals critical

  9. Monitoring the drug-sensitivity of Plasmodium falciparum in coastal towns in Madagascar by use of in vitro chemosensitivity and mutation detection tests

    Directory of Open Access Journals (Sweden)

    Rason M.A.

    2002-09-01

    Full Text Available The dissemination of mutant and resistant strains of Plasmodium falciparum makes a considerable contribution to the spread of drug-resistant malaria. Populations around harbours and airports could be particularly exposed to Plasmodium isolates introduced with imported cases of malaria. The use of chloroquine as well as the use of and sulfadoxine/pyrimethamine is currently an effective method for treating uncomplicated cases of malaria in Madagascar. As part of a monitoring programme, in vitro methods were used to assess the sensitivity of P. falciparum isolates in two coastal towns in Madagascar: Mahajanga on the west coast and Toamasina on the east coast. All of the isolates from both sites were sensitive to amodiaquine, quinine, pyrimethamine and cycloguanil. All of the isolates from Mahajanga were sensitive to chloroquine (n = 25; mean IC50 = 22.6 nM, 95 % confidence interval: 16.8-28.7 nM, whereas three of the isolates from Toamasina were resistant to chloroquine (n = 18; mean IC50 = 66.3 nM; 95 % confidence interval : 42.6-90 nM, The frequency of the Pfcrt Thr-76 and the dhfr Asn- 108 mutations was estimated by PCR/RFLP. The 43 P. falciparum isolates examined, including the three in vitro chloroquine-resistant isolates from Toamasina were all wild-type (Lys-76. Phenotyping and genotyping studies suggested that the prevalence of chloroquine- and pyrimethamine-resistant isolates and of mutant strains of P. falciparum is very low. These results showed that in vitro test and genotyping of resistance markers approaches could be successfully used to monitor the emergence of drug-resistant malaria and to try to alleviate the lack of medical teams able to carry out in vivo test. The possible hazard/risk associated with imported cases of malaria is discussed.

  10. Prognostic significance of 5-fluorouracil metabolism-relating enzymes and enhanced chemosensitivity to 5-fluorouracil by 5-chloro 2,4-dihydroxy-pyridine in urothelial carcinoma

    Directory of Open Access Journals (Sweden)

    Ide Hiroki

    2012-09-01

    Full Text Available Abstract Background Recently, S-1, a novel 5-fluorouracil (5-FU-based agent containing the strong dihydropyrimidine dehydrogenase (DPD inhibitor, 5-chloro-2,4-dihydropyrimidine (CDHP has been clinically used to treat various non-urothelial carcinomas (UC. High levels of thymidylate synthase (TS, the target enzyme of 5-FU and DPD which degrades the majority of 5-FU, are associated with poor prognosis in some cancers. However, only a few reports have dealt with this in UC. The aim of this study was to investigate the clinical significance of TS and DPD in upper tract urothelial carcinoma (UTUC and evaluate the role of TS and DPD on the sensitivity of 5-FU in UC cell lines and the anti-tumor effect of S-1 in UC xenograft model. Methods Firstly, we evaluated the immunohistochemical expression of TS and DPD in 176 patients with UTUC to determine their prognostic significance. Secondly, the levels of TS and DPD in UC cell lines were measured by ELISA and real-time PCR. Furthermore, the association between their levels and the sensitivity to 5-FU was examined using the small interfering RNA (siRNA specific for TS and DPD. Thirdly, the anti-tumor effect of S-1 was evaluated in UC xenograft model. Results Immunohistochemical evaluation of TS and DPD in UTUC human samples revealed that TS expression was significantly associated with stage, grade, and lymphovascular invasion and DPD expression was significantly associated with grade. Multivariate analysis revealed that high TS expression was an independent predictor of disease-specific survival in them. In in vitro study using UC cell lines, high levels of TS and DPD were associated with low response to 5-FU and these associations were confirmed with siRNA specific for TS and DPD. In in vivo study using UC xenograft model, S-1 treatment dramatically inhibited tumor growth compared to controls, tegafur, or UFT in UC tumor with a high level of DPD. Conclusions TS plays an important role in the prognosis of UTUC and S-1 may be a key agent for UC tumor, especially with a high level of DPD.

  11. Situation awareness with systems of systems

    CERN Document Server

    Tretmans, Jan; Borth, Michael

    2013-01-01

    This book discusses various aspects, challenges, and solutions for developing systems-of-systems for situation awareness, using applications in the domain of maritime safety and security.  Topics include advanced, multi-objective visualization methods for situation awareness, stochastic outlier selection, rule-based anomaly detection, an ontology-based event model for semantic reasoning, new methods for semi-automatic generation of adapters bridging communication gaps, security policies for systems-of-systems, trust assessment, and methods to deal with the dynamics of systems-of-systems in run-time monitoring, testing, and diagnosis. Architectural considerations for designing information-centric systems-of-systems such as situation awareness systems, and an integrated demonstrator implementing many of the investigated aspects, complete the book.

  12. Computer System Design System-on-Chip

    CERN Document Server

    Flynn, Michael J

    2011-01-01

    The next generation of computer system designers will be less concerned about details of processors and memories, and more concerned about the elements of a system tailored to particular applications. These designers will have a fundamental knowledge of processors and other elements in the system, but the success of their design will depend on the skills in making system-level tradeoffs that optimize the cost, performance and other attributes to meet application requirements. This book provides a new treatment of computer system design, particularly for System-on-Chip (SOC), which addresses th

  13. Smart electromechanical systems the central nervous system

    CERN Document Server

    Kurbanov, Vugar

    2017-01-01

    This book describes approaches to solving the problems of developing the central nervous system of robots (CNSR) based on smart electromechanical systems (SEMS) modules, principles of construction of the various modules of the central nervous system and variants of mathematical software CNSR in control systems for intelligent robots. It presents the latest advances in theory and practice at the Russian Academy of Sciences. Developers of intelligent robots to solve modern problems in robotics are increasingly addressing the use of the bionic approach to create robots that mimic the complexity and adaptability of biological systems. These have smart electromechanical system (SEMS), which are used in various cyber-physical systems (CPhS), and allow the functions of calculation, control, communications, information storage, monitoring, measurement and control of parameters and environmental parameters to be integrated. The behavior of such systems is based on the information received from the central nervous syst...

  14. Linking Political Systems and War Systems

    DEFF Research Database (Denmark)

    Harste, Gorm

    2009-01-01

    Decisive parts of the Western political system have demonstrated a seemingly surprising misinterpretation of military might. As Madelaine Albright has suggested, the mighty perceived themselves as "almighty". Political power seems to have invested in instrumental coercive power relations and found...... military coercion to be the appropriate mean. Using the system theory and the theory of systemic risks displayed by the German sociologist Niklas Luhmann the article demonstrates how military systems due to their own autonomy and autopoiesis do not fit into the idea of political government....... The Clausewitzian ideal of a political system that could continue its power games by means of war was moderated by Clausewitz' own analysis of "friction". How can a political system be so blind towards the possibilities of another system? What are the risks of systemic blind spots? The argument of the paper...

  15. Designing information systems

    CERN Document Server

    Blethyn, Stanley G

    2014-01-01

    Designing Information Systems focuses on the processes, methodologies, and approaches involved in designing information systems. The book first describes systems, management and control, and how to design information systems. Discussions focus on documents produced from the functional construction function, users, operators, analysts, programmers and others, process management and control, levels of management, open systems, design of management information systems, and business system description, partitioning, and leveling. The text then takes a look at functional specification and functiona

  16. LCLS XTOD Attenuator System System Concept Report

    Energy Technology Data Exchange (ETDEWEB)

    Kishiyama, K; Roeben, M; Trent, J; Ryutov, D; Shen, S

    2006-04-12

    The attenuator system for the Linac Coherent Light Source (LCLS) X-ray Transport, Optics and Diagnostics (XTOD) system has been configured and analyzed by the Lawrence Livermore National Laboratory's New Technologies Engineering Division (NTED) as requested by the SLAC/LCLS program. The system layout, performance analyses and selection of the vacuum components are presented in this System Conceptual Review (SCR) report. Also included are the plans for prototype, procurement, mechanical integration, and the cost estimates.

  17. Engine Auxiliary System Guideline: Lubricating Oil Systems

    OpenAIRE

    Linna, Joni

    2015-01-01

    This thesis was done for Wärtsilä Technical Services organization, the purpose of this work was to gather and structure information about the lubricating oil systems from the company’s internal databases, interviews with system specialists and from different literature sources covering Ship Power and Power Plant products. The outcome was a guideline, covering typical power plant and marine system descriptions, all components used in the lubricating oil system with their functional description...

  18. COMPARISON TRADITIONAL SYSTEMS OF TUNNEL FORMWORK SYSTEM

    OpenAIRE

    ERKAN, İbrahim Hakkı; Yılmaz, Ülkü Sultan; Türken, Hakan

    2011-01-01

    Tunnel formwork systems became the most widespread construction technology preferred in recent years in Turkey due to rapidity and economy. In this study, before all else, a brief information was given about the types and construction techniques of tunnel formwork systems. Then a reinforced concrete building sample was firstly modeled as it was constructed with the tunnel formwork system and secondly modeled as it was formed by a frame system with shear walls constructed by the traditional re...

  19. Modeling learning technology systems as business systems

    NARCIS (Netherlands)

    Avgeriou, Paris; Retalis, Symeon; Papaspyrou, Nikolaos

    2003-01-01

    The design of Learning Technology Systems, and the Software Systems that support them, is largely conducted on an intuitive, ad hoc basis, thus resulting in inefficient systems that defectively support the learning process. There is now justifiable, increasing effort in formalizing the engineering o

  20. The complement system in systemic autoimmune disease

    NARCIS (Netherlands)

    Chen, Min; Daha, Mohamed R.; Kallenberg, Cees G. M.

    2010-01-01

    Complement is part of the innate immune system. Its major function is recognition and elimination of pathogens via direct killing and/or stimulation of phagocytosis. Activation of the complement system is, however, also involved in the pathogenesis of the systemic autoimmune diseases. Activation via

  1. General Systems Theory and Instructional Systems Design.

    Science.gov (United States)

    Salisbury, David F.

    1990-01-01

    Describes basic concepts in the field of general systems theory (GST) and identifies commonalities that exist between GST and instructional systems design (ISD). Models and diagrams that depict system elements in ISD are presented, and two matrices that show how GST has been used in ISD literature are included. (11 references) (LRW)

  2. Observing System Evaluations Using GODAE Systems

    Science.gov (United States)

    2009-09-01

    Journal of Marine Systems 35...dimensional temperature fields: A first approach based on simulated observations. Journal of Marine Systems 46:85-98. Langland, R.H., and N.L. Baker...capabilities of multisatellite altimeter missions: First results with real data in the Mediterranean Sea. Journal of Marine Systems 65:190-211.

  3. Optical system defect propagation in ABCD systems

    DEFF Research Database (Denmark)

    McKinley, W.G.; Yura, H.T.; Hanson, Steen Grüner

    1988-01-01

    We describe how optical system defects (tilt/jitter, decenter, and despace) propagate through an arbitrary paraxial optical system that can be described by an ABCD ray transfer matrix. A pedagogical example is given that demonstrates the effect of alignment errors on a typical optical system....... © 1988 Optical Society of America...

  4. Expert Systems for auditing management information systems

    Directory of Open Access Journals (Sweden)

    Gheroghe Popescu

    2007-05-01

    Full Text Available Expert systems are built with the help of: specialised programming languages or expert system generators (shell. But this structure was reached after tens of years of work and research, because expert systems are nothing but pragmatic capitalisation of the results of research carried out in artificial intelligence and theory of knowledge.

  5. Non linear system become linear system

    Directory of Open Access Journals (Sweden)

    Petre Bucur

    2007-01-01

    Full Text Available The present paper refers to the theory and the practice of the systems regarding non-linear systems and their applications. We aimed the integration of these systems to elaborate their response as well as to highlight some outstanding features.

  6. Operating System Security

    CERN Document Server

    Jaeger, Trent

    2008-01-01

    Operating systems provide the fundamental mechanisms for securing computer processing. Since the 1960s, operating systems designers have explored how to build "secure" operating systems - operating systems whose mechanisms protect the system against a motivated adversary. Recently, the importance of ensuring such security has become a mainstream issue for all operating systems. In this book, we examine past research that outlines the requirements for a secure operating system and research that implements example systems that aim for such requirements. For system designs that aimed to

  7. Psychology of system design

    CERN Document Server

    Meister, D

    2014-01-01

    This is a book about systems, including: systems in which humans control machines; systems in which humans interact with humans and the machine component is relatively unimportant; systems which are heavily computerized and those that are not; and governmental, industrial, military and social systems. The book deals with both traditional systems like farming, fishing and the military, and with systems just now tentatively emerging, like the expert and the interactive computer system. The emphasis is on the system concept and its implications for analysis, design and evaluation of these many di

  8. Biomedical signals and systems

    CERN Document Server

    Tranquillo, Joseph V

    2013-01-01

    Biomedical Signals and Systems is meant to accompany a one-semester undergraduate signals and systems course. It may also serve as a quick-start for graduate students or faculty interested in how signals and systems techniques can be applied to living systems. The biological nature of the examples allows for systems thinking to be applied to electrical, mechanical, fluid, chemical, thermal and even optical systems. Each chapter focuses on a topic from classic signals and systems theory: System block diagrams, mathematical models, transforms, stability, feedback, system response, control, time

  9. Autonomous photovoltaic lighting system

    OpenAIRE

    Ahmed A. A. Hafez; Montesinos Miracle, Daniel; Sudrià Andreu, Antoni

    2012-01-01

    This paper introduces a comparison between the conventional and Photovoltaic (PV) lighting systems. A simple sizing procedure for a PV stand-alone system was advised. The paper also proposes a novel PV lighting system. The proposed system is simple, compact and reliable. The system operation was investigated by thoroughly mathematical and simulation work.

  10. Lighting system with thermal management system

    Energy Technology Data Exchange (ETDEWEB)

    Arik, Mehmet; Weaver, Stanton Earl; Stecher, Thomas Elliot; Seeley, Charles Erklin; Kuenzler, Glenn Howard; Wolfe, Jr, Charles Franklin; Utturkar, Yogen Vishwas; Sharma, Rajdeep; Prabhakaran, Satish; Icoz, Tunc

    2016-10-11

    Lighting systems having unique configurations are provided. For instance, the lighting system may include a light source, a thermal management system and driver electronics, each contained within a housing structure. The light source is configured to provide illumination visible through an opening in the housing structure. The thermal management system is configured to provide an air flow, such as a unidirectional air flow, through the housing structure in order to cool the light source. The driver electronics are configured to provide power to each of the light source and the thermal management system.

  11. Lighting system with thermal management system

    Science.gov (United States)

    Arik, Mehmet; Weaver, Stanton; Stecher, Thomas; Seeley, Charles; Kuenzler, Glenn; Wolfe, Jr., Charles; Utturkar, Yogen; Sharma, Rajdeep; Prabhakaran, Satish; Icoz, Tunc

    2013-05-07

    Lighting systems having unique configurations are provided. For instance, the lighting system may include a light source, a thermal management system and driver electronics, each contained within a housing structure. The light source is configured to provide illumination visible through an opening in the housing structure. The thermal management system is configured to provide an air flow, such as a unidirectional air flow, through the housing structure in order to cool the light source. The driver electronics are configured to provide power to each of the light source and the thermal management system.

  12. Systems Measures of Water Distribution System Resilience

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murray, Regan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Resilience is a concept that is being used increasingly to refer to the capacity of infrastructure systems to be prepared for and able to respond effectively and rapidly to hazardous events. In Section 2 of this report, drinking water hazards, resilience literature, and available resilience tools are presented. Broader definitions, attributes and methods for measuring resilience are presented in Section 3. In Section 4, quantitative systems performance measures for water distribution systems are presented. Finally, in Section 5, the performance measures and their relevance to measuring the resilience of water systems to hazards is discussed along with needed improvements to water distribution system modeling tools.

  13. Operating System Performance Analyzer for Embedded Systems

    Directory of Open Access Journals (Sweden)

    Shahzada Khayyam Nisar

    2011-11-01

    Full Text Available RTOS provides a number of services to an embedded system designs such as case management, memory management, and Resource Management to build a program. Choosing the best OS for an embedded system is based on the available OS for system designers and their previous knowledge and experience. This can cause an imbalance between the OS and embedded systems. RTOS performance analysis is critical in the design and integration of embedded software to ensure that limits the application meet at runtime. To select an appropriate operating system for an embedded system for a particular application, the OS services to be analyzed. These OS services are identified by parameters to establish performance metrics. Performance Metrics selected include context switching, Preemption time and interrupt latency. Performance Metrics are analyzed to choose the right OS for an embedded system for a particular application.

  14. Mapping biological systems to network systems

    CERN Document Server

    Rathore, Heena

    2016-01-01

    The book presents the challenges inherent in the paradigm shift of network systems from static to highly dynamic distributed systems – it proposes solutions that the symbiotic nature of biological systems can provide into altering networking systems to adapt to these changes. The author discuss how biological systems – which have the inherent capabilities of evolving, self-organizing, self-repairing and flourishing with time – are inspiring researchers to take opportunities from the biology domain and map them with the problems faced in network domain. The book revolves around the central idea of bio-inspired systems -- it begins by exploring why biology and computer network research are such a natural match. This is followed by presenting a broad overview of biologically inspired research in network systems -- it is classified by the biological field that inspired each topic and by the area of networking in which that topic lies. Each case elucidates how biological concepts have been most successfully ...

  15. Systems Architecture for a Nationwide Healthcare System.

    Science.gov (United States)

    Abin, Jorge; Nemeth, Horacio; Friedmann, Ignacio

    2015-01-01

    From a national level to give Internet technology support, the Nationwide Integrated Healthcare System in Uruguay requires a model of Information Systems Architecture. This system has multiple healthcare providers (public and private), and a strong component of supplementary services. Thus, the data processing system should have an architecture that considers this fact, while integrating the central services provided by the Ministry of Public Health. The national electronic health record, as well as other related data processing systems, should be based on this architecture. The architecture model described here conceptualizes a federated framework of electronic health record systems, according to the IHE affinity model, HL7 standards, local standards on interoperability and security, as well as technical advice provided by AGESIC. It is the outcome of the research done by AGESIC and Systems Integration Laboratory (LINS) on the development and use of the e-Government Platform since 2008, as well as the research done by the team Salud.uy since 2013.

  16. Calo trigger acquisition system

    CERN Multimedia

    Franchini, Matteo

    2016-01-01

    Calo trigger acquisition system - Evolution of the acquisition system from a multiple boards system (upper, orange cables) to a single board one (below, light blue cables) where all the channels are collected in a single board.

  17. What Are Expert Systems?

    Science.gov (United States)

    d'Agapeyeff, A.

    1986-01-01

    Intended for potential business users, this paper describes the main characteristics of expert systems; discusses practical use considerations; presents a taxonomy of the systems; and reviews several expert system development projects in business and industry. (MBR)

  18. for hybrid dynamical systems

    Directory of Open Access Journals (Sweden)

    Wassim M. Haddad

    2001-01-01

    Full Text Available In this paper we develop a unified dynamical systems framework for a general class of systems possessing left-continuous flows; that is, left-continuous dynamical systems. These systems are shown to generalize virtually all existing notions of dynamical systems and include hybrid, impulsive, and switching dynamical systems as special cases. Furthermore, we generalize dissipativity, passivity, and nonexpansivity theory to left-continuous dynamical systems. Specifically, the classical concepts of system storage functions and supply rates are extended to left-continuous dynamical systems providing a generalized hybrid system energy interpretation in terms of stored energy, dissipated energy over the continuous-time dynamics, and dissipated energy over the resetting events. Finally, the generalized dissipativity notions are used to develop general stability criteria for feedback interconnections of left-continuous dynamical systems. These results generalize the positivity and small gain theorems to the case of left-continuous, hybrid, and impulsive dynamical systems.

  19. Manned systems technology discipline

    Science.gov (United States)

    Bretoi, Remus

    1990-01-01

    Viewgraphs on manned systems technology discipline for Space Station Freedom are presented. Topics covered include: crew-systems interfaces and interactions; crew training; on-board systems maintenance and support; habitability and environment; and computational human factors.

  20. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  1. Autonomic Nervous System Disorders

    Science.gov (United States)

    Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart ... breathing and swallowing Erectile dysfunction in men Autonomic nervous system disorders can occur alone or as the result ...

  2. Brain and Nervous System

    Science.gov (United States)

    ... Your 1- to 2-Year-Old Brain and Nervous System KidsHealth > For Parents > Brain and Nervous System Print ... brain is quite the juggler. Anatomy of the Nervous System If you think of the brain as a ...

  3. The Trinity System

    Energy Technology Data Exchange (ETDEWEB)

    Archer, Billy Joe [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vigil, Benny Manuel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-13

    This paper describes the Trinity system, the first ASC Advanced Technology System (ATS-1). We describe the Trinity procurement timeline, the ASC computing strategy, the Trinity specific mission needs, and the Trinity system specifications.

  4. Law System in Japan

    OpenAIRE

    Andreea Lorena Ponaru

    2007-01-01

    This article attempts to present and explain the main features of the japanese law system. Japanese Law system was reformed during the domination of Tokugawa shogun family. In 1870, Foreign Governmental Systems Study Office was founded. By judicial sentences many french laws were introduced in Japanese law system. Roma-Tokyo-Berlin Alliance (1936) introduced a strong German influence in the law system. The Japanese judicial system has known five periods. In the first (1869-1888) were introduc...

  5. Small test SDHW systems

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different.......Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different....

  6. Battery systems engineering

    CERN Document Server

    Rahn, Christopher D

    2012-01-01

    A complete all-in-one reference on the important interdisciplinary topic of Battery Systems Engineering Focusing on the interdisciplinary area of battery systems engineering, this book provides the background, models, solution techniques, and systems theory that are necessary for the development of advanced battery management systems. It covers the topic from the perspective of basic electrochemistry as well as systems engineering topics and provides a basis for battery modeling for system engineering of electric and hybrid electric vehicle platforms. This original

  7. Neural Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — As part of the Electrical and Computer Engineering Department and The Institute for System Research, the Neural Systems Laboratory studies the functionality of the...

  8. Aeronautical Information System -

    Data.gov (United States)

    Department of Transportation — The Aeronautical Information System (AIS) is a leased weather automated system that provides a means of collecting and distributing aeronautical weather information...

  9. RECURSIVE SYSTEM IDENTIFICATION

    Institute of Scientific and Technical Information of China (English)

    Han-Fu Chen

    2009-01-01

    Most of existing methods in system identification with possible exception of those for linear systems are off-line in nature, and hence are nonrecursive.This paper demonstrates the recent progress in recursive system identification.The recursive identifi-cation algorithms are presented not only for linear systems (multivariate ARMAX systems) but also for nonlinear systems such as the Hammerstein and Wiener systems, and the non-linear ARX systems.The estimates generated by the algorithms are online updated and converge a.s.to the true values as time tends to infinity.

  10. Control system design method

    Science.gov (United States)

    Wilson, David G [Tijeras, NM; Robinett, III, Rush D.

    2012-02-21

    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  11. Airports Geographic Information System -

    Data.gov (United States)

    Department of Transportation — The Airports Geographic Information System maintains the airport and aeronautical data required to meet the demands of the Next Generation National Airspace System....

  12. Credit Management System

    Data.gov (United States)

    US Agency for International Development — Credit Management System. Outsourced Internet-based application. CMS stores and processes data related to USAID credit programs. The system provides information...

  13. Integrated Systems Health Management for Intelligent Systems

    Science.gov (United States)

    Figueroa, Fernando; Melcher, Kevin

    2011-01-01

    The implementation of an integrated system health management (ISHM) capability is fundamentally linked to the management of data, information, and knowledge (DIaK) with the purposeful objective of determining the health of a system. It is akin to having a team of experts who are all individually and collectively observing and analyzing a complex system, and communicating effectively with each other in order to arrive at an accurate and reliable assessment of its health. In this paper, concepts, procedures, and approaches are presented as a foundation for implementing an intelligent systems ]relevant ISHM capability. The capability stresses integration of DIaK from all elements of a system. Both ground-based (remote) and on-board ISHM capabilities are compared and contrasted. The information presented is the result of many years of research, development, and maturation of technologies, and of prototype implementations in operational systems.

  14. Epilogue: Systems Approaches and Systems Practice

    Science.gov (United States)

    Reynolds, Martin; Holwell, Sue

    Each of the five systems approaches discussed in this volume: system dynamics (SD), the viable systems model (VSM), strategic options development and analysis (SODA), soft systems methodology (SSM) and critical systems heuristics (CSH) has a pedigree. Not in the sense of the sometimes absurd spectacle of animals paraded at dog shows. Rather, their pedigree derives from their systems foundations, their capacity to evolve and their flexibility in use. None of the five approaches has developed out of use in restricted and controlled contexts of either low or high levels of complicatedness. Neither has any one of them evolved as a consequence of being applied only to situations with either presumed stakeholder agreement on purpose, or courteous disagreement amongst stakeholders, or stakeholder coercion. The compilation is not a celebration of abstract ‘methodologies', but of theoretically robust approaches that have a genuine pedigree in practice.

  15. Metadata Management System for Healthcare Information Systems

    OpenAIRE

    Patil, Ketan Shripat

    2011-01-01

    The Utah Department of Health (UDOH) uses multiple and diverse healthcare information systems for managing, maintaining, and sharing the health information. To keep track of the important details about these information systems such as the operational details, data semantics, data exchange standards, and personnel responsible for maintaining and managing it is a monumental task, with several limitations. This report describes the design and implementation of the Metadata Management System (MD...

  16. L-system fractals

    CERN Document Server

    Mishra, Jibitesh

    2007-01-01

    The book covers all the fundamental aspects of generating fractals through L-system. Also it provides insight to various researches in this area for generating fractals through L-system approach & estimating dimensions. Also it discusses various applications of L-system fractals. Key Features: - Fractals generated from L-System including hybrid fractals - Dimension calculation for L-system fractals - Images & codes for L-system fractals - Research directions in the area of L-system fractals - Usage of various freely downloadable tools in this area - Fractals generated from L-System including hybrid fractals- Dimension calculation for L-system fractals- Images & codes for L-system fractals- Research directions in the area of L-system fractals- Usage of various freely downloadable tools in this area

  17. Forming different planetary systems

    Institute of Scientific and Technical Information of China (English)

    Ji-Lin Zhou; Ji-Wei Xie; Hui-Gen Liu; Hui Zhang; Yi-Sui Sun

    2012-01-01

    With the increasing number of detected exoplanet samples,the statistical properties of planetary systems have become much clearer.In this review,we summarize the major statistical results that have been revealed mainly by radial velocity and transiting observations,and try to interpret them within the scope of the classical core-accretion scenario of planet formation,especially in the formation of different orbital architectures for planetary systems around main sequence stars.Based on the different possible formation routes for different planet systems,we tentatively classify them into three major catalogs:hot Jupiter systems,standard systems and distant giant planet systems.The standard systems can be further categorized into three sub-types under different circumstances:solar-like systems,hot Super-Earth systems,and subgiant planet systems.We also review the theory of planet detection and formation in binary systems as well as planets in star clusters.

  18. Hot Spot Removal System: System description

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System`s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section.

  19. Novel central nervous system drug delivery systems.

    Science.gov (United States)

    Stockwell, Jocelyn; Abdi, Nabiha; Lu, Xiaofan; Maheshwari, Oshin; Taghibiglou, Changiz

    2014-05-01

    For decades, biomedical and pharmaceutical researchers have worked to devise new and more effective therapeutics to treat diseases affecting the central nervous system. The blood-brain barrier effectively protects the brain, but poses a profound challenge to drug delivery across this barrier. Many traditional drugs cannot cross the blood-brain barrier in appreciable concentrations, with less than 1% of most drugs reaching the central nervous system, leading to a lack of available treatments for many central nervous system diseases, such as stroke, neurodegenerative disorders, and brain tumors. Due to the ineffective nature of most treatments for central nervous system disorders, the development of novel drug delivery systems is an area of great interest and active research. Multiple novel strategies show promise for effective central nervous system drug delivery, giving potential for more effective and safer therapies in the future. This review outlines several novel drug delivery techniques, including intranasal drug delivery, nanoparticles, drug modifications, convection-enhanced infusion, and ultrasound-mediated drug delivery. It also assesses possible clinical applications, limitations, and examples of current clinical and preclinical research for each of these drug delivery approaches. Improved central nervous system drug delivery is extremely important and will allow for improved treatment of central nervous system diseases, causing improved therapies for those who are affected by central nervous system diseases.

  20. Power system protection 2 systems and methods

    CERN Document Server

    1995-01-01

    The worldwide growth in demand for electricity has forced the pace of developments in electrical power system design to meet consumer needs for reliable, secure and cheap supplies. Power system protection, as a technology essential to high quality supply, is widely recognised as a specialism of growing and often critical importance, in which power system needs and technological progress have combined to result in rapid developments in policy and practice in recent years. In the United Kingdom, the need for appropriate training in power system protection was recognised in the early 1960s with t

  1. Recommender Systems for Social Tagging Systems

    CERN Document Server

    Balby Marinho, Leandro

    2012-01-01

    Social Tagging Systems are web applications in which users upload resources (e.g., bookmarks, videos, photos, etc.) and annotate it with a list of freely chosen keywords called tags. This is a grassroots approach to organize a site and help users to find the resources they are interested in. Social tagging systems are open and inherently social; features that have been proven to encourage participation. However, with the large popularity of these systems and the increasing amount of user-contributed content, information overload rapidly becomes an issue. Recommender Systems are well known appl

  2. Site systems engineering: Systems engineering management plan

    Energy Technology Data Exchange (ETDEWEB)

    Grygiel, M.L. [Westinghouse Hanford Co., Richland, WA (United States)

    1996-05-03

    The Site Systems Engineering Management Plan (SEMP) is the Westinghouse Hanford Company (WHC) implementation document for the Hanford Site Systems Engineering Policy, (RLPD 430.1) and Systems Engineering Criteria Document and Implementing Directive, (RLID 430.1). These documents define the US Department of Energy (DOE), Richland Operations Office (RL) processes and products to be used at Hanford to implement the systems engineering process at the site level. This SEMP describes the products being provided by the site systems engineering activity in fiscal year (FY) 1996 and the associated schedule. It also includes the procedural approach being taken by the site level systems engineering activity in the development of these products and the intended uses for the products in the integrated planning process in response to the DOE policy and implementing directives. The scope of the systems engineering process is to define a set of activities and products to be used at the site level during FY 1996 or until the successful Project Hanford Management Contractor (PHMC) is onsite as a result of contract award from Request For Proposal DE-RP06-96RL13200. Following installation of the new contractor, a long-term set of systems engineering procedures and products will be defined for management of the Hanford Project. The extent to which each project applies the systems engineering process and the specific tools used are determined by the project`s management.

  3. ERP–systems

    OpenAIRE

    Shustova I.

    2016-01-01

    In this work, we analyzed the existing ERP–systems of foreign and domestic manufacturers. Popular ERP–systems in the Republic of Belarus were considered. The leading ERP-systems in the domestic market and their features were described in detail. Finally, we described the steps that must be taken to select the most suitable ERP-system for a particular company.

  4. Information Systems Security Audit

    Directory of Open Access Journals (Sweden)

    Gheorghe Popescu

    2007-12-01

    Full Text Available The article covers:Defining an information system; benefits obtained by introducing new information technologies; IT management;Defining prerequisites, analysis, design, implementation of IS; Information security management system; aspects regarding IS security policy; Conceptual model of a security system; Auditing information security systems and network infrastructure security.

  5. Hybrid intelligent engineering systems

    CERN Document Server

    Jain, L C; Adelaide, Australia University of

    1997-01-01

    This book on hybrid intelligent engineering systems is unique, in the sense that it presents the integration of expert systems, neural networks, fuzzy systems, genetic algorithms, and chaos engineering. It shows that these new techniques enhance the capabilities of one another. A number of hybrid systems for solving engineering problems are presented.

  6. CDMA systems capacity engineering

    CERN Document Server

    Kim, Kiseon

    2004-01-01

    This new hands-on resource tackles capacity planning and engineering issues that are crucial to optimizing wireless communication systems performance. Going beyond the system physical level and investigating CDMA system capacity at the service level, this volume is the single-source for engineering and analyzing systems capacity and resources.

  7. Expert Systems: An Overview.

    Science.gov (United States)

    Adiga, Sadashiv

    1984-01-01

    Discusses: (1) the architecture of expert systems; (2) features that distinguish expert systems from conventional programs; (3) conditions necessary to select a particular application for the development of successful expert systems; (4) issues to be resolved when building expert systems; and (5) limitations. Examples of selected expert systems…

  8. Universal Index System

    Science.gov (United States)

    Kelley, Steve; Roussopoulos, Nick; Sellis, Timos; Wallace, Sarah

    1993-01-01

    The Universal Index System (UIS) is an index management system that uses a uniform interface to solve the heterogeneity problem among database management systems. UIS provides an easy-to-use common interface to access all underlying data, but also allows different underlying database management systems, storage representations, and access methods.

  9. Measuring Systemic Risk

    DEFF Research Database (Denmark)

    Acharya, Viral V.; Heje Pedersen, Lasse; Philippon, Thomas

    We present a simple model of systemic risk and we show that each financial institution's contribution to systemic risk can be measured as its systemic expected shortfall (SES), i.e., its propensity to be undercapitalized when the system as a whole is undercapitalized. SES increases...

  10. STEP electronic system design

    Science.gov (United States)

    Couch, R. H.; Johnson, J. W.

    1984-01-01

    The STEP electronic system design is discussed. The purpose of the design is outlined. The electronic system design is summarized and it is found that: an effective conceptual system design is developed; the design represents a unique set of capabilities; makes efficient use of available orbiter resources; the system capabilities exceed identified potential experiment needs.

  11. Medical imaging systems

    Science.gov (United States)

    Frangioni, John V

    2013-06-25

    A medical imaging system provides simultaneous rendering of visible light and diagnostic or functional images. The system may be portable, and may include adapters for connecting various light sources and cameras in open surgical environments or laparascopic or endoscopic environments. A user interface provides control over the functionality of the integrated imaging system. In one embodiment, the system provides a tool for surgical pathology.

  12. Product Service Systems

    DEFF Research Database (Denmark)

    Departing from Product Development models based on physical artefacts. Moving towards integrated Product Development and System Operations models suited Product/Service-systems......Departing from Product Development models based on physical artefacts. Moving towards integrated Product Development and System Operations models suited Product/Service-systems...

  13. Information Systems Security Audit

    OpenAIRE

    Gheorghe Popescu; Veronica Adriana Popescu; Cristina Raluca Popescu

    2007-01-01

    The article covers:Defining an information system; benefits obtained by introducing new information technologies; IT management;Defining prerequisites, analysis, design, implementation of IS; Information security management system; aspects regarding IS security policy; Conceptual model of a security system; Auditing information security systems and network infrastructure security.

  14. Type Systems for Bigraphs

    DEFF Research Database (Denmark)

    Elsborg, Ebbe; Hildebrandt, Thomas; Sangiorgi, Davide

    of controls and a set of reaction rules, collectively a bigraphical reactive system (BRS). Possible advantages of developing bigraphical type systems include: a deeper understanding of a type system itself and its properties; transfer of the type systems to the concrete family of calculi that the BRS models...

  15. Exploring Enterprise, System of Systems, and System and Software Architectures

    Science.gov (United States)

    2016-06-13

    might. • For example, software architects often lament the lateness with which they are brought into system engineering projects. • All of these...Enterprise architects compose holistic solutions that address the business challenges of the enterprise and support the governance needed to...network. • Today, Army systems are connected to inter-agency networks, and change management is even more critical. • Army enterprise architects must

  16. On generalized Volterra systems

    Science.gov (United States)

    Charalambides, S. A.; Damianou, P. A.; Evripidou, C. A.

    2015-01-01

    We construct a large family of evidently integrable Hamiltonian systems which are generalizations of the KM system. The algorithm uses the root system of a complex simple Lie algebra. The Hamiltonian vector field is homogeneous cubic but in a number of cases a simple change of variables transforms such a system to a quadratic Lotka-Volterra system. We present in detail all such systems in the cases of A3, A4 and we also give some examples from higher dimensions. We classify all possible Lotka-Volterra systems that arise via this algorithm in the An case.

  17. Dynamical system synchronization

    CERN Document Server

    Luo, Albert C J

    2013-01-01

    Dynamical System Synchronization (DSS) meticulously presents for the first time the theory of dynamical systems synchronization based on the local singularity theory of discontinuous dynamical systems. The book details the sufficient and necessary conditions for dynamical systems synchronizations, through extensive mathematical expression. Techniques for engineering implementation of DSS are clearly presented compared with the existing techniques.  This book also:  Presents novel concepts and methods for dynamical system synchronization Extends beyond the Lyapunov theory for dynamical system synchronization Introduces companion and synchronization of discrete dynamical systems Includes local singularity theory for discontinuous dynamical systems Covers the invariant domains of synchronization Features more than 75 illustrations Dynamical System Synchronization is an ideal book for those interested in better understanding new concepts and methodology for dynamical system synchronization, local singularity...

  18. [Universal coaxial anesthetic system].

    Science.gov (United States)

    Ungerer, M J; le Roux, F P

    1978-02-25

    A true universal co-axial anaesthetic system has been designed. This system may be used either as a Mapleson A circuit during spontaneous ventilation or as a Mapleson D circuit during controlled ventilation. Conversion to either system may be conveniently carried out by interchanging the pop-off valve and fresh gas inlet, without disconnecting the system from the patient. Resistance to flow of both tubes has been measured and was found to be within acceptable limits. The efficiency of this system in a Mapleson A arrangement was compared with that of a conventional Magill circuit during spontaneous breathing in 2 conscious volunteers. It was shown that no significant difference exists between these systems eith regard to rebreathing, and that the universal co-axial system may be used as efficiently and economically as the Magill circuit during spontaneous ventilation. The co-axial system can be easily connected to a circle system, combining the advantages of the two systems.

  19. Variable Structure Systems and Systems Zeros

    OpenAIRE

    El-Ghezawi, O.M.E.; S. A. Billings; Zinober, A.S.I.

    1981-01-01

    The analysis of variable structure systems in the sliding mode yields the concept of equivalent control which leads naturally to a new method for determining the zeros and zero directions of linear multivariable systems. The analysis presented is conceptually easy and computationally attractive.

  20. The Solar System as an Exoplanetary System

    CERN Document Server

    Martin, Rebecca G

    2015-01-01

    With the availability of considerably more data, we revisit the question of how special our Solar System is, compared to observed exoplanetary systems. To this goal, we employ a mathematical transformation that allows for a meaningful, statistical comparison. We find that the masses and densities of the giant planets in our Solar System are very typical, as is the age of the Solar System. While the orbital location of Jupiter is somewhat of an outlier, this is most likely due to strong selection effects towards short-period planets. The eccentricities of the planets in our Solar System are relatively small compared to those in observed exosolar systems, but still consistent with the expectations for an 8-planet system (and could, in addition, reflect a selection bias towards high-eccentricity planets). The two characteristics of the Solar System that we find to be most special are the lack of super-Earths with orbital periods of days to months and the general lack of planets inside of the orbital radius of Me...

  1. Applications of membrane systems in distributed systems

    Institute of Scientific and Technical Information of China (English)

    Aneta Binder; Rudolf Freund; Georg Lojka; Marion Oswald

    2007-01-01

    Based on the biological model of cell-to-cell communication proposed by A. Rustom et al. (Science, 2004, 303: 1007-1010), we investigate the possibilities to apply P systems with dynamic channels transporting membrane vesicles for describing processes in distributed systems.

  2. Performance, Performance System, and High Performance System

    Science.gov (United States)

    Jang, Hwan Young

    2009-01-01

    This article proposes needed transitions in the field of human performance technology. The following three transitions are discussed: transitioning from training to performance, transitioning from performance to performance system, and transitioning from learning organization to high performance system. A proposed framework that comprises…

  3. Antifungal activity of redox-active benzaldehydes that target cellular antioxidation

    Directory of Open Access Journals (Sweden)

    Mahoney Noreen

    2011-05-01

    Full Text Available Abstract Background Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. Natural phenolic compounds can serve as potent redox cyclers that inhibit microbial growth through destabilization of cellular redox homeostasis and/or antioxidation systems. The aim of this study was to identify benzaldehydes that disrupt the fungal antioxidation system. These compounds could then function as chemosensitizing agents in concert with conventional drugs or fungicides to improve antifungal efficacy. Methods Benzaldehydes were tested as natural antifungal agents against strains of Aspergillus fumigatus, A. flavus, A. terreus and Penicillium expansum, fungi that are causative agents of human invasive aspergillosis and/or are mycotoxigenic. The yeast Saccharomyces cerevisiae was also used as a model system for identifying gene targets of benzaldehydes. The efficacy of screened compounds as effective chemosensitizers or as antifungal agents in formulations was tested with methods outlined by the Clinical Laboratory Standards Institute (CLSI. Results Several benzaldehydes are identified having potent antifungal activity. Structure-activity analysis reveals that antifungal activity increases by the presence of an ortho-hydroxyl group in the aromatic ring. Use of deletion mutants in the oxidative stress-response pathway of S. cerevisiae (sod1Δ, sod2Δ, glr1Δ and two mitogen-activated protein kinase (MAPK mutants of A. fumigatus (sakAΔ, mpkCΔ, indicates antifungal activity of the benzaldehydes is through disruption of cellular antioxidation. Certain benzaldehydes, in combination with phenylpyrroles, overcome tolerance of A. fumigatus MAPK mutants to this agent and/or increase sensitivity of fungal pathogens to mitochondrial respiration inhibitory agents. Synergistic chemosensitization greatly lowers minimum inhibitory (MIC or fungicidal (MFC

  4. Photovoltaic systems and applications

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    Abstracts are given of presentations given at a project review meeting held at Albuquerque, NM. The proceedings cover the past accomplishments and current activities of the Photovoltaic Systems Research, Balance-of-System Technology Development and System Application Experiments Projects at Sandia National Laboratories. The status of intermediate system application experiments and residential system analysis is emphasized. Some discussion of the future of the Photovoltaic Program in general, and the Sandia projects in particular is also presented.

  5. HYBRID VEHICLE CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Dvadnenko

    2016-06-01

    Full Text Available The hybrid vehicle control system includes a start–stop system for an internal combustion engine. The system works in a hybrid mode and normal vehicle operation. To simplify the start–stop system, there were user new possibilities of a hybrid car, which appeared after the conversion. Results of the circuit design of the proposed system of basic blocks are analyzed.

  6. Intrusion Detection System: Security Monitoring System

    Directory of Open Access Journals (Sweden)

    ShabnamNoorani,

    2015-10-01

    Full Text Available An intrusion detection system (IDS is an ad hoc security solution to protect flawed computer systems. It works like a burglar alarm that goes off if someone tampers with or manages to get past other security mechanisms such as authentication mechanisms and firewalls. An Intrusion Detection System (IDS is a device or a software application that monitors network or system activities for malicious activities or policy violations and produces reports to a management station.Intrusion Detection System (IDS has been used as a vital instrument in defending the network from this malicious or abnormal activity..In this paper we are comparing host based and network based IDS and various types of attacks possible on IDS.

  7. Systems Theory and Systems Approach to Leadership

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Berim Ramosaj

    2014-06-01

    Full Text Available Systems theory is product of the efforts of many researchers to create an intermediate field of coexistence of all sciences. If not for anything else, because of the magnitude that the use of systemic thinking and systemic approach has taken, it has become undisputed among the theories. Systems theory not only provides a glossary of terms with which researchers from different fields can be understood, but provides a framework for the presentation and interpretation of phenomena and realities. This paper addresses a systematic approach to leadership, as an attempt to dredge leadership and systems theory literature to find the meeting point. Systems approach is not an approach to leadership in terms of a manner of leader’s work, but it’s the leader's determination to factorize in his leadership the external environment and relationships with and among elements. Leader without followers is unable to exercise his leadership and to ensure their conviction he should provide a system, a structure, a purpose, despite the alternative chaos. Systems approach clarifies the thought on the complexity and dynamism of the environment and provides a framework for building ideas. If the general system theory is the skeleton of science (Boulding: 1956, this article aims to replenish it with leadership muscles by prominent authors who have written on systems theory and leadership, as well as through original ideas. In this work analytical methods were used (by analyzing approaches individually as well as synthetic methods (by assaying individual approaches in context of entirety. The work is a critical review of literature as well as a deductive analysis mingled with models proposed by authors through inductive analysis. Meta-analysis has been used to dissect the interaction and interdependence between leadership approaches.

  8. A distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Verho, P.; Jaerventausta, P.; Kaerenlampi, M.; Paulasaari, H. [Tampere Univ. of Technology (Finland); Partanen, J. [Lappeenranta Univ. of Technology (Finland)

    1996-12-31

    The development of new distribution automation applications is considerably wide nowadays. One of the most interesting areas is the development of a distribution management system (DMS) as an expansion of the traditional SCADA system. At the power transmission level such a system is called an energy management system (EMS). The idea of these expansions is to provide supporting tools for control center operators in system analysis and operation planning. The needed data for new applications is mainly available in some existing systems. Thus the computer systems of utilities must be integrated. The main data source for the new applications in the control center are the AM/FM/GIS (i.e. the network database system), the SCADA, and the customer information system (CIS). The new functions can be embedded in some existing computer system. This means a strong dependency on the vendor of the existing system. An alternative strategy is to develop an independent system which is integrated with other computer systems using well-defined interfaces. The latter approach makes it possible to use the new applications in various computer environments, having only a weak dependency on the vendors of the other systems. In the research project this alternative is preferred and used in developing an independent distribution management system

  9. A System of Systems Approach to the EU Energy System

    Science.gov (United States)

    Jess, Tom; Madani, Kaveh; Mahlooji, Maral; Ristic, Bora

    2016-04-01

    Around the world, measures to prevent dangerous climate change are being adopted and may change energy systems fundamentally. The European Union (EU) is committed to reducing greenhouse gas emission by 20% by 2020 and by 80-95% by 2050. In order to achieve this, EU member states aim to increase the share of renewables in the energy mix to 20% by 2020. This commitment comes as part of a series of other aims, principles, and policies to reform the EU's energy system. Cost-efficiency in the emissions reductions measures as well as strategic goals under the Resource Efficient Europe flagship initiative which would include a more prudent approach to other natural resources such as water and land. Using the "System of Systems Approach", as from Hadian and Madani (2015), energy sources' Relative Aggregate Footprints (RAF) in the EU are evaluated. RAF aggregates across four criteria: carbon footprint, water footprint, land footprint, and economic cost. The four criteria are weighted by resource availability across the EU and for each Member State. This provides an evaluation of the overall resource use efficiency of the EU's energy portfolio and gives insight into the differences in the desirability of energy sources across Member States. Broadly, nuclear, onshore wind, and geothermal are most desirable under equal criteria weights and EU average weighting introduces only small changes in the relative performance of only few technologies. The member state specific weightings show that most countries have similar energy technology preferences. However, the UK deviates most strongly from the average, with an even stronger preference for nuclear and coal. Sweden, Malta and Finland also deviate from the typical preferences indicating the complexity in play in reforming the EU energy system. Reference Hadian S, Madani K (2015) A System of Systems Approach to Energy Sustainability Assessment: Are All Renewables Really Green? Ecological Indicators, 52, 194-206.

  10. Intelligent systems technology infrastructure for integrated systems

    Science.gov (United States)

    Lum, Henry

    1991-01-01

    A system infrastructure must be properly designed and integrated from the conceptual development phase to accommodate evolutionary intelligent technologies. Several technology development activities were identified that may have application to rendezvous and capture systems. Optical correlators in conjunction with fuzzy logic control might be used for the identification, tracking, and capture of either cooperative or non-cooperative targets without the intensive computational requirements associated with vision processing. A hybrid digital/analog system was developed and tested with a robotic arm. An aircraft refueling application demonstration is planned within two years. Initially this demonstration will be ground based with a follow-on air based demonstration. System dependability measurement and modeling techniques are being developed for fault management applications. This involves usage of incremental solution/evaluation techniques and modularized systems to facilitate reuse and to take advantage of natural partitions in system models. Though not yet commercially available and currently subject to accuracy limitations, technology is being developed to perform optical matrix operations to enhance computational speed. Optical terrain recognition using camera image sequencing processed with optical correlators is being developed to determine position and velocity in support of lander guidance. The system is planned for testing in conjunction with Dryden Flight Research Facility. Advanced architecture technology is defining open architecture design constraints, test bed concepts (processors, multiple hardware/software and multi-dimensional user support, knowledge/tool sharing infrastructure), and software engineering interface issues.

  11. Modeling Power Systems as Complex Adaptive Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chassin, David P.; Malard, Joel M.; Posse, Christian; Gangopadhyaya, Asim; Lu, Ning; Katipamula, Srinivas; Mallow, J V.

    2004-12-30

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today's most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This report explores the state-of-the-art physical analogs for understanding the behavior of some econophysical systems and deriving stable and robust control strategies for using them. We review and discuss applications of some analytic methods based on a thermodynamic metaphor, according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood. We apply these methods to the question of how power markets can be expected to behave under a variety of conditions.

  12. Rover waste assay system

    Energy Technology Data Exchange (ETDEWEB)

    Akers, D.W.; Stoots, C.M.; Kraft, N.C.; Marts, D.J. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1997-11-01

    The Rover Waste Assay System (RWAS) is a nondestructive assay system designed for the rapid assay of highly-enriched {sup 235}U contaminated piping, tank sections, and debris from the Rover nuclear rocket fuel processing facility at the Idaho Chemical Processing Plant. A scanning system translates a NaI(Tl) detector/collimator system over the structural components where both relative and calibrated measurements for {sup 137}Cs are made. Uranium-235 concentrations are in operation and is sufficiently automated that most functions are performed by the computer system. These functions include system calibration, problem identification, collimator control, data analysis, and reporting. Calibration of the system was done through a combination of measurements on calibration standards and benchmarked modeling. A description of the system is presented along with the methods and uncertainties associated with the calibration and analysis of the system for components from the Rover facility. 4 refs., 2 figs., 4 tabs.

  13. Enhanced nurse call systems.

    Science.gov (United States)

    2001-04-01

    This Evaluation focuses on high-end computerized nurse call systems--what we call enhanced systems. These are highly flexible systems that incorporate microprocessor and communications technologies to expand the capabilities of the nurse call function. Enhanced systems, which vary in configuration from one installation to the next, typically consist of a basic system that provides standard nurse call functionality and a combination of additional enhancements that provide the added functionality the facility desires. In this study, we examine the features that distinguish enhanced nurse call systems from nonenhanced systems, focusing on their application and benefit to healthcare facilities. We evaluated seven systems to determine how well they help (1) improve patient care, as well as increase satisfaction with the care provided, and (2) improve caregiver efficiency, as well as increase satisfaction with the work environment. We found that all systems meet these objectives, but not all systems perform equally well for all implementations. Our ratings will help facilities identify those systems that offer the most effective features for their intended use. The study also includes a Technology Management Guide to help readers (1) determine whether they'll benefit from the capabilities offered by enhanced systems and (2) target a system for purchase and equip the system for optimum performance and cost-effective operation.

  14. Nonlinearity of colloid systems oxyhydrate systems

    CERN Document Server

    Sucharev, Yuri I

    2008-01-01

    The present monograph is the first systematic study of the non-linear characteristic of gel oxy-hydrate systems involving d- and f- elements. These are the oxyhydrates of rare-earth elements and oxides - hydroxides of d- elements (zirconium, niobium, titanium, etc.) The non-linearity of these gel systems introduces fundamental peculiarities into their structure and, consequently, their properties. The polymer-conformational diversity of energetically congenial gel fragments, which continu-ously transform under the effect of, for instance, system dissipation heat, is central to the au-thor's hy

  15. Embedded systems handbook networked embedded systems

    CERN Document Server

    Zurawski, Richard

    2009-01-01

    Considered a standard industry resource, the Embedded Systems Handbook provided researchers and technicians with the authoritative information needed to launch a wealth of diverse applications, including those in automotive electronics, industrial automated systems, and building automation and control. Now a new resource is required to report on current developments and provide a technical reference for those looking to move the field forward yet again. Divided into two volumes to accommodate this growth, the Embedded Systems Handbook, Second Edition presents a comprehensive view on this area

  16. Smart SDHW systems

    DEFF Research Database (Denmark)

    Andersen, Elsa

    2000-01-01

    The aim of the project is to develop smart solar domestic hot water (SDHW) systems. A smart SDHW is a system in which the domestic water can bee heated both by solar collectors and by an auxiliary energy supply system. The auxiliary energy supply system heats up the hot-water tank from the top...... periods in a laboratory. Numeric models of the systems have been developed. The models are verified with measured temperatures and energy quantities. In order to verify the good test results in the laboratory two of the smart SDHW systems have been installed in practice. Measurements will bee carried out...

  17. Microelectronic systems 1 checkbook

    CERN Document Server

    Vears, R E

    2013-01-01

    Microelectronic Systems 1 Checkbook provides coverage of the Business and Technician Education Council level 1 unit in Microelectronic Systems. However, it can be regarded as a basic textbook in microelectronic systems for a much wider range of studies. Each topic considered in the text is presented in a way that assumes the reader has little prior knowledge of electronics. The aim of the book is to provide an introduction to the concept of systems, to differentiate analogue and digital systems, and to describe the nature of microprocessor-controlled systems. An introduction to programming is

  18. Introducing Systems Approaches

    Science.gov (United States)

    Reynolds, Martin; Holwell, Sue

    Systems Approaches to Managing Change brings together five systems approaches to managing complex issues, each having a proven track record of over 25 years. The five approaches are: System Dynamics (SD) developed originally in the late 1950s by Jay Forrester Viable Systems Model (VSM) developed originally in the late 1960s by Stafford Beer Strategic Options Development and Analysis (SODA: with cognitive mapping) developed originally in the 1970s by Colin Eden Soft Systems Methodology (SSM) developed originally in the 1970s by Peter Checkland Critical Systems Heuristics (CSH) developed originally in the late 1970s by Werner Ulrich

  19. Micro Information Systems

    DEFF Research Database (Denmark)

    Ulslev Pedersen, Rasmus; Kühn Pedersen, Mogens

    2014-01-01

    We are increasingly surrounded by and using small systems, which are equipped with sensors. Mobile phones, temperature sensors, GPS tracking, emerging nano/micro-size sensors, and similar technologies are used by individuals, groups, and organizations. There are valuable applications for industries...... such as medical and manufacturing. These new sensor applications have implications for information systems (IS) and, the authors visualize this new class of information systems as fractals growing from an established class of systems; namely that of information systems (IS). The identified applications....... The chapter demonstrates the proposed micro-IS framework with a working (open source) application of open demand response systems that address the engineering aspects of this work....

  20. Continuous system modeling

    Science.gov (United States)

    Cellier, Francois E.

    1991-01-01

    A comprehensive and systematic introduction is presented for the concepts associated with 'modeling', involving the transition from a physical system down to an abstract description of that system in the form of a set of differential and/or difference equations, and basing its treatment of modeling on the mathematics of dynamical systems. Attention is given to the principles of passive electrical circuit modeling, planar mechanical systems modeling, hierarchical modular modeling of continuous systems, and bond-graph modeling. Also discussed are modeling in equilibrium thermodynamics, population dynamics, and system dynamics, inductive reasoning, artificial neural networks, and automated model synthesis.

  1. Generalized L systems

    Institute of Scientific and Technical Information of China (English)

    陆汝钤; 张文妍

    2002-01-01

    This paper proposes the concept of generalized L systems, GL systems for short, which can describe asynchronized concurrent phenomena. We have proved that the GL systems are proper extensions of the traditional L systems. We have also defined a classification of GL systems and proved a sufficient and necessary condition for the equivalence of two subclasses of GL systems: two quivalent, iff k = j and there exists a common divisor g of all mr and a common divisor h of all ni such that i: mi/g = ni/h.

  2. Information system development activities and inquiring systems

    DEFF Research Database (Denmark)

    Carugati, Andrea

    2008-01-01

    This article presents a framework that maps information system development (ISD) activities on systems for the creation of knowledge. This work addresses the relevant and persisting problem of improving the chances of ISD success. The article builds upon previous research on knowledge aspects...... provides a new way to see the development of a system in terms of the knowledge created in the process. The main practical implication of the framework is that it improves the managers' ability to guide ISD activities as knowledge activities embedded in a knowledge process, a crucial element in development...... of ISD, abandoning the idea of a monolithic approach to knowledge and presenting a pluralistic approach based on the idea that different inquiring systems can support micro-level ISD activities. The article is divided into two parts. The first part presents the theoretical development of the framework...

  3. Test System Impact on System Availability

    DEFF Research Database (Denmark)

    Pau, L. F.

    1987-01-01

    The specifications are presented for an imperfect automatic test system (ATS) (test frequency distribution, reliability, false alarm rate, nondetection rate) in order to account for the availability, readiness, mean time between unscheduled repairs (MTBUR), reliability, and maintenance of the sys......The specifications are presented for an imperfect automatic test system (ATS) (test frequency distribution, reliability, false alarm rate, nondetection rate) in order to account for the availability, readiness, mean time between unscheduled repairs (MTBUR), reliability, and maintenance...... of the system subject to monitoring and test. A time-dependent Markov model is presented, and applied in three cases, with examples of numerical results provided for preventive maintenance decisions, design of an automatic test system, buffer testing in computers, and data communications....

  4. Business System Planning Project System Requirements Specification

    Energy Technology Data Exchange (ETDEWEB)

    NELSON, R.E.

    2000-09-08

    The purpose of the Business Systems Planning Project System Requirements Specification (SRS) is to provide the outline and contents of the requirements for the CH2M HILL Hanford Group, Inc. (CHG) integrated business and technical information systems. The SRS will translate proposed objectives into the statement of the functions that are to be performed and data and information flows that they require. The requirements gathering methodology will use (1) facilitated group requirement sessions; (2) individual interviews; (3) surveys; and (4) document reviews. The requirements will be verified and validated through coordination of the technical requirement team and CHG Managers. The SRS document used the content and format specified in Lockheed Martin Services, Inc. Organization Standard Software Practices in conjunction with the Institute of Electrical and Electronics Engineers Standard 8340-1984 for Systems Requirements Documents.

  5. SUBSURFACE EMPLACEMENT TRANSPORTATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    T. Wilson; R. Novotny

    1999-11-22

    The objective of this analysis is to identify issues and criteria that apply to the design of the Subsurface Emplacement Transportation System (SET). The SET consists of the track used by the waste package handling equipment, the conductors and related equipment used to supply electrical power to that equipment, and the instrumentation and controls used to monitor and operate those track and power supply systems. Major considerations of this analysis include: (1) Operational life of the SET; (2) Geometric constraints on the track layout; (3) Operating loads on the track; (4) Environmentally induced loads on the track; (5) Power supply (electrification) requirements; and (6) Instrumentation and control requirements. This analysis will provide the basis for development of the system description document (SDD) for the SET. This analysis also defines the interfaces that need to be considered in the design of the SET. These interfaces include, but are not limited to, the following: (1) Waste handling building; (2) Monitored Geologic Repository (MGR) surface site layout; (3) Waste Emplacement System (WES); (4) Waste Retrieval System (WRS); (5) Ground Control System (GCS); (6) Ex-Container System (XCS); (7) Subsurface Electrical Distribution System (SED); (8) MGR Operations Monitoring and Control System (OMC); (9) Subsurface Facility System (SFS); (10) Subsurface Fire Protection System (SFR); (11) Performance Confirmation Emplacement Drift Monitoring System (PCM); and (12) Backfill Emplacement System (BES).

  6. System Information Distribution in Massive MIMO Systems

    OpenAIRE

    Sörman, Simon

    2016-01-01

    The 5th generation mobile telecommunication system (5G) is currently being specified and developed, with large expectations on throughput and efficiency. While 4G and more specifically LTE might constitute a basis of the design of the network, there are some parts that should be improved. One thing to improve is the static signalling that occurs very frequently in a 4G network, of which system information such as synchronization signals, detection of network frequencies, operators, configurat...

  7. Mathematical System Theory and System Modeling

    OpenAIRE

    1980-01-01

    Choosing models related effectively to the questions to be addressed is a central issue in the craft of systems analysis. Since the mathematical description the analyst chooses constrains the types of issues he candeal with, it is important for these models to be selected so as to yield limitations that are acceptable in view of the questions the systems analysis seeks to answer. In this paper, the author gives an overview of the central issues affecting the question of model choice. To ...

  8. EPICS system: system structure and user interface

    Energy Technology Data Exchange (ETDEWEB)

    West, R.E.; Bartlett, J.F.; Bobbitt, J.S.; Lahey, T.E.; Kramper, B.J.; MacKinnon, B.A.

    1984-02-01

    This paper present the user's view of and the general organization of the EPICS control system at Fermilab. Various subsystems of the EPICS control system are discussed. These include the user command language, software protection, the device database, remote computer interfaces, and several application utilities. This paper is related to two other papers on EPICS: an overview paper and a detailed implementation paper.

  9. Operating System for Runtime Reconfigurable Multiprocessor Systems

    Directory of Open Access Journals (Sweden)

    Diana Göhringer

    2011-01-01

    Full Text Available Operating systems traditionally handle the task scheduling of one or more application instances on processor-like hardware architectures. RAMPSoC, a novel runtime adaptive multiprocessor System-on-Chip, exploits the dynamic reconfiguration on FPGAs to generate, start and terminate hardware and software tasks. The hardware tasks have to be transferred to the reconfigurable hardware via a configuration access port. The software tasks can be loaded into the local memory of the respective IP core either via the configuration access port or via the on-chip communication infrastructure (e.g. a Network-on-Chip. Recent-series of Xilinx FPGAs, such as Virtex-5, provide two Internal Configuration Access Ports, which cannot be accessed simultaneously. To prevent conflicts, the access to these ports as well as the hardware resource management needs to be controlled, e.g. by a special-purpose operating system running on an embedded processor. For that purpose and to handle the relations between temporally and spatially scheduled operations, the novel approach of an operating system is of high importance. This special purpose operating system, called CAP-OS (Configuration Access Port-Operating System, which will be presented in this paper, supports the clients using the configuration port with the services of priority-based access scheduling, hardware task mapping and resource management.

  10. Integrated Reporting Information System -

    Data.gov (United States)

    Department of Transportation — The Integrated Reporting Information System (IRIS) is a flexible and scalable web-based system that supports post operational analysis and evaluation of the National...

  11. VT DSL Systems 2006

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT DSL Broadband System dataset (DSL2006) includes polygons depicting the extent of Vermont's DSL broadband system as of 12/31/2006. This data...

  12. Inductive Monitoring System (IMS)

    Data.gov (United States)

    National Aeronautics and Space Administration — IMS: Inductive Monitoring System The Inductive Monitoring System (IMS) is a tool that uses a data mining technique called clustering to extract models of normal...

  13. Interstitial hydrogen storage system

    Energy Technology Data Exchange (ETDEWEB)

    Gell, H.A.

    1980-09-30

    A metal hydride fuel system is described that incorporates a plurality of storage elements that may be individually replaced to provide a hydrogen fuel system for combustion engines having a capability of partial refueling is presented.

  14. Geographical information systems

    DEFF Research Database (Denmark)

    Möller, Bernd

    2004-01-01

    The chapter gives an introduction to Geographical Information Systems (GIS) with particular focus on their application within environmental management.......The chapter gives an introduction to Geographical Information Systems (GIS) with particular focus on their application within environmental management....

  15. Voluntary Service System (VSS)

    Data.gov (United States)

    Department of Veterans Affairs — Voluntary Service System (VSS) is a national-level application which replaced the site-based Voluntary Timekeeping System (VTK). VTK was used for many years at the...

  16. Semiotic labelled deductive systems

    Energy Technology Data Exchange (ETDEWEB)

    Nossum, R.T. [Imperial College of Science, Technology and Medicine, London (United Kingdom)

    1996-12-31

    We review the class of Semiotic Models put forward by Pospelov, as well as the Labelled Deductive Systems developed by Gabbay, and construct an embedding of Semiotic Models into Labelled Deductive Systems.

  17. Flight Systems Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I project will develop the Flight System Monitor which will use non-intrusive electrical monitoring (NEMO). The electronic system health of...

  18. Generalized adjoint systems

    CERN Document Server

    Serakos, Demetrios

    2015-01-01

    This book defines and develops the generalized adjoint of an input-output system. It is the result of a theoretical development and examination of the generalized adjoint concept and the conditions under which systems analysis using adjoints is valid. Results developed in this book are useful aids for the analysis and modeling of physical systems, including the development of guidance and control algorithms and in developing simulations. The generalized adjoint system is defined and is patterned similarly to adjoints of bounded linear transformations. Next the elementary properties of the generalized adjoint system are derived. For a space of input-output systems, a generalized adjoint map from this space of systems to the space of generalized adjoints is defined. Then properties of the generalized adjoint map are derived. Afterward the author demonstrates that the inverse of an input-output system may be represented in terms of the generalized adjoint. The use of generalized adjoints to determine bounds for ...

  19. Systemic banking crises

    OpenAIRE

    O. Emre Ergungor; James B. Thomson

    2005-01-01

    Systemic banking crises can have devastating effects on the economies of developing or industrialized countries. This Policy Discussion Paper reviews the factors that weaken banking systems and make them more susceptible to crises.

  20. Silver recovery system data

    Energy Technology Data Exchange (ETDEWEB)

    Boulineau, B.

    1991-08-26

    In August of 1990 the Savannah River Site Photography Group began testing on a different type of silver recovery system. This paper describes the baseline study and the different phases of installation and testing of the system.

  1. Prosthetic Knee Systems

    Science.gov (United States)

    ... us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Prosthetic Knee Systems Translated into plain language by Helen ... Health Literacy Consulting Original article by Bill Dupes Prosthetic knee systems are among the most complex of ...

  2. Human Resource Accounting System

    Science.gov (United States)

    Cerullo, Michael J.

    1974-01-01

    Main objectives of human resource accounting systems are to satisfy the informational demands made by investors and by operating managers. The paper's main concern is with the internal uses of a human asset system. (Author)

  3. Saturated Switching Systems

    CERN Document Server

    Benzaouia, Abdellah

    2012-01-01

    Saturated Switching Systems treats the problem of actuator saturation, inherent in all dynamical systems by using two approaches: positive invariance in which the controller is designed to work within a region of non-saturating linear behaviour; and saturation technique which allows saturation but guarantees asymptotic stability. The results obtained are extended from the linear systems in which they were first developed to switching systems with uncertainties, 2D switching systems, switching systems with Markovian jumping and switching systems of the Takagi-Sugeno type. The text represents a thoroughly referenced distillation of results obtained in this field during the last decade. The selected tool for analysis and design of stabilizing controllers is based on multiple Lyapunov functions and linear matrix inequalities. All the results are illustrated with numerical examples and figures many of them being modelled using MATLAB®. Saturated Switching Systems will be of interest to academic researchers in con...

  4. Information retrieval system

    Science.gov (United States)

    Berg, R. F.; Holcomb, J. E.; Kelroy, E. A.; Levine, D. A.; Mee, C., III

    1970-01-01

    Generalized information storage and retrieval system capable of generating and maintaining a file, gathering statistics, sorting output, and generating final reports for output is reviewed. File generation and file maintenance programs written for the system are general purpose routines.

  5. Rainfed intensive crop systems

    DEFF Research Database (Denmark)

    Olesen, Jørgen E

    2014-01-01

    This chapter focuses on the importance of intensive cropping systems in contributing to the world supply of food and feed. The impact of climate change on intensive crop production systems is also discussed....

  6. BioSystems

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NCBI BioSystems Database provides integrated access to biological systems and their component genes, proteins, and small molecules, as well as literature...

  7. Designing automatic resupply systems.

    Science.gov (United States)

    Harding, M L

    1999-02-01

    This article outlines the process for designing and implementing autoresupply systems. The planning process includes determination of goals and appropriate participation. Different types of autoresupply mechanisms include kanban, breadman, consignment, systems contracts, and direct shipping from an MRP schedule.

  8. Visitor Registration System

    Data.gov (United States)

    US Agency for International Development — Visitor Registration System (VRS) streamlines visitor check-in and check-out process for expediting visitors into USAID. The system captures visitor information...

  9. Central nervous system

    Science.gov (United States)

    The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main "processing center" for your entire nervous system. They control all the workings of your body.

  10. Multiple System Atrophy (MSA)

    Science.gov (United States)

    Diseases and Conditions Multiple system atrophy (MSA) By Mayo Clinic Staff Multiple system atrophy (MSA) is a rare neurological disorder that impairs your body's involuntary (autonomic) functions, including blood ...

  11. Health System Measurement Project

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Health System Measurement Project tracks government data on critical U.S. health system indicators. The website presents national trend data as well as detailed...

  12. Immune System and Disorders

    Science.gov (United States)

    Your immune system is a complex network of cells, tissues, and organs that work together to defend against germs. It ... t, to find and destroy them. If your immune system cannot do its job, the results can be ...

  13. Cross Disciplinary Biometric Systems

    CERN Document Server

    Liu, Chengjun

    2012-01-01

    Cross disciplinary biometric systems help boost the performance of the conventional systems. Not only is the recognition accuracy significantly improved, but also the robustness of the systems is greatly enhanced in the challenging environments, such as varying illumination conditions. By leveraging the cross disciplinary technologies, face recognition systems, fingerprint recognition systems, iris recognition systems, as well as image search systems all benefit in terms of recognition performance.  Take face recognition for an example, which is not only the most natural way human beings recognize the identity of each other, but also the least privacy-intrusive means because people show their face publicly every day. Face recognition systems display superb performance when they capitalize on the innovative ideas across color science, mathematics, and computer science (e.g., pattern recognition, machine learning, and image processing). The novel ideas lead to the development of new color models and effective ...

  14. Audit Management System

    CERN Document Server

    Alconada, Federico

    2015-01-01

    In the need of renewing their system, the Internal Audit department has given a proposal for building a new one. Taking into consideration the problems of their system they elaborated a requirement's list with the functionalities and features they were expecting from the new management system. This new system would be primarily for the use of the Internal Audit staff but it would also support the follow-up of internal audit recommendations by potentially all CERN staff members.

  15. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    a differential action, which allows differential equations as primitive actions. The extension allows us to model hybrid systems with both continuous and discrete behaviour. The main result of this paper is an extension of such a hybrid action system with parallel composition. The extension does not change...... the original meaning of the parallel composition, and therefore also the ordinary action systems can be composed in parallel with the hybrid action systems....

  16. Wireless power transfer system

    OpenAIRE

    Arai, Hiroyuki

    2012-01-01

    This paper presents a survey of recent wireless power transfer systems. The issue of wireless power transfer is to achieve a highly efficient system with small positioning errors of the facilities setting. Several theories have been presented to obtain precise system design. This paper presents a summary of design theory for short range power transfer systems and detailed formulations based on a circuit model and an array of infinitesimal dipoles. In addition to these theories, this paper in...

  17. The DISCUS Hardware System,

    Science.gov (United States)

    1982-07-01

    it physically impossible for one processor to access another’s local program or workspace. It should be noted that the system - generator should handle...this gateway would be complex and how it would be used and linked to the system generator would also be difficult. Because of this it worth asking...which is by no means trivial to write, identified several faults in the system generator and operating system that would have otherwise been

  18. Unix operating system

    CERN Document Server

    Liu, Yukun; Guo, Liwei

    2011-01-01

    ""UNIX Operating System: The Development Tutorial via UNIX Kernel Services"" introduces the hierarchical structure, principles, applications, kernel, shells, development, and management of the UNIX operation systems multi-dimensionally and systematically. It clarifies the natural bond between physical UNIX implementation and general operating system and software engineering theories, and presents self-explanatory illustrations for readers to visualize and understand the obscure relationships and intangible processes in UNIX operating system. This book is intended for engineers and researchers

  19. Spacecraft Energy Storage Systems

    OpenAIRE

    Robinson, Wilf; Hanks, James; Spina, Len; Havenhill, Doug; Gisler, Gary; Ginter, Steve; Brault, Sharon

    1997-01-01

    Flywheel Energy Storage Systems represent an exciting alternative to traditional battery storage systems used to power satellites during periods of eclipse. The increasing demand for reliable communication and data access is driving explosive growth in the number of satellite systems being developed as well as their performance requirements. Power on orbit is the key to this performance, and batteries are becoming increasingly unattractive as an energy storage media. Flywheel systems offer ve...

  20. Computational Systems Chemical Biology

    OpenAIRE

    Oprea, Tudor I.; Elebeoba E. May; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically-based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology, SCB (Oprea et al., 2007).

  1. Linear system theory

    Science.gov (United States)

    Callier, Frank M.; Desoer, Charles A.

    1991-01-01

    The aim of this book is to provide a systematic and rigorous access to the main topics of linear state-space system theory in both the continuous-time case and the discrete-time case; and the I/O description of linear systems. The main thrusts of the work are the analysis of system descriptions and derivations of their properties, LQ-optimal control, state feedback and state estimation, and MIMO unity-feedback systems.

  2. CCD digital radiography system

    Science.gov (United States)

    Wang, Yi; Kang, Xi; Li, Yuanjing; Cheng, Jianping; Hou, Yafei; Han, Haiwei

    2009-07-01

    Amorphous silicon flat-panel detector is the mainstream used in digital radiography (DR) system. In latest years, scintillation screen coupled with CCD DR is becoming more popular in hospital. Compared with traditional amorphous silicon DR, CCD-DR has better spatial resolution and has little radiation damage. It is inexpensive and can be operated easily. In this paper, A kind of CCD based DR system is developed. We describe the construction of the system, the system performances and experiment results.

  3. Recovery Systems Design Guide

    Science.gov (United States)

    1978-12-01

    14 1.9 Gemini Paraglider Deployment ......................................... 14 1.10 Apollo Recovery System Deployment...45 to 15 g’s. The fied land landing by Paraglider and an ejection seat automatic sequencing system deployed the drogue back-up system as the means for... Paraglider system should not be higher altitudes and speeds. There was no reserve ready for early Gemini flights. The intention was to drogue parachute

  4. Electric Vehicle Propulsion System

    OpenAIRE

    2014-01-01

    Electric vehicles are being considered as one of the pillar of eco-friendly solutions to overcome the problem of global pollution and radiations due to greenhouse gases. Present thesis work reports the improvement in overall performance of the propulsion system of an electric vehicle by improving autonomy and torque-speed characteristic. Electric vehicle propulsion system consists of supply and traction system, and are coordinated by the monitoring & control system. Case of light electric veh...

  5. Computer system identification

    OpenAIRE

    Lesjak, Borut

    2008-01-01

    The concept of computer system identity in computer science bears just as much importance as does the identity of an individual in a human society. Nevertheless, the identity of a computer system is incomparably harder to determine, because there is no standard system of identification we could use and, moreover, a computer system during its life-time is quite indefinite, since all of its regular and necessary hardware and software upgrades soon make it almost unrecognizable: after a number o...

  6. Open quantum system identification

    CERN Document Server

    Schirmer, Sophie G; Zhou, Weiwei; Gong, Erling; Zhang, Ming

    2012-01-01

    Engineering quantum systems offers great opportunities both technologically and scientifically for communication, computation, and simulation. The construction and operation of large scale quantum information devices presents a grand challenge and a major issue is the effective control of coherent dynamics. This is often in the presence of decoherence which further complicates the task of determining the behaviour of the system. Here, we show how to determine open system Markovian dynamics of a quantum system with restricted initialisation and partial output state information.

  7. Quantum System Identification

    OpenAIRE

    Burgarth, Daniel; Yuasa, Kazuya

    2011-01-01

    The aim of quantum system identification is to estimate the ingredients inside a black box, in which some quantum-mechanical unitary process takes place, by just looking at its input-output behavior. Here we establish a basic and general framework for quantum system identification, that allows us to classify how much knowledge about the quantum system is attainable, in principle, from a given experimental setup. Prior knowledge on some elements of the black box helps the system identification...

  8. Space power systems technology

    Science.gov (United States)

    Coulman, George A.

    1994-01-01

    Reported here is a series of studies which examine several potential catalysts and electrodes for some fuel cell systems, some materials for space applications, and mathematical modeling and performance predictions for some solid oxide fuel cells and electrolyzers. The fuel cell systems have a potential for terrestrial applications in addition to solar energy conversion in space applications. Catalysts and electrodes for phosphoric acid fuel cell systems and for polymer electrolyte membrane (PEM) fuel cell and electrolyzer systems were examined.

  9. Content management systems (CMS)

    OpenAIRE

    Oriahi, Harrison

    2014-01-01

    This thesis describes the three most common and widely used content management systems (CMS) used to power several millions of business websites on the internet. Since there are many other content managements systems online, this report provides some helpful guides on each of the three most used systems and the web design projects that each of them maybe most suitable. There are plenty of options when it comes to selecting a content management system for a development project and this the...

  10. System programming languages

    OpenAIRE

    ŠMIT, MATEJ

    2016-01-01

    Most operating systems are written in the C programming language. Similar is with system software, for example, device drivers, compilers, debuggers, disk checkers, etc. Recently some new programming languages emerged, which are supposed to be suitable for system programming. In this thesis we present programming languages D, Go, Nim and Rust. We defined the criteria which are important for deciding whether programming language is suitable for system programming. We examine programming langua...

  11. Radiant Floor Cooling Systems

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.

    2008-01-01

    In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

  12. Logistics Management Information System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The logistics information is the logistics manageme nt 's inevitable request. The paper introduces several kinds of logistics informat ion system and their functions in the logistics management, such as the warehous e management system (WMS) in the delivery center, the control system for transpo rtation and delivery, the supply chain management (SCM), the optimization of th e logistics system, etc. In the author's opinion, the development of logistics could been divided into four phases. And the logistic...

  13. Compositional asynchronous membrane systems

    Institute of Scientific and Technical Information of China (English)

    Cosmin Bonchis; Cornel Izbasa; Gabriel Ciobanu

    2007-01-01

    This paper presents an algorithmic way of building complex membrane systems by coupling elementary membranes. Its application seems particularly valuable in the case of asynchronous membrane systems, since the resulting membrane system remains asynchronous. The composition method is based on a handshake mechanism implemented by using antiport rules and promoters.

  14. MILITARY INFORMATION SYSTEMS,

    Science.gov (United States)

    upward are usually indications of how effectively the system is developing or operating. The use of computers in information systems tends to increase...computers into information systems must always begin at the lowest level of aggregation in the job hierarchy. Only those information-processing jobs

  15. Solar tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  16. Information extraction system

    Science.gov (United States)

    Lemmond, Tracy D; Hanley, William G; Guensche, Joseph Wendell; Perry, Nathan C; Nitao, John J; Kidwell, Paul Brandon; Boakye, Kofi Agyeman; Glaser, Ron E; Prenger, Ryan James

    2014-05-13

    An information extraction system and methods of operating the system are provided. In particular, an information extraction system for performing meta-extraction of named entities of people, organizations, and locations as well as relationships and events from text documents are described herein.

  17. System integration report

    Science.gov (United States)

    Badler, N. I.; Korein, J. D.; Meyer, C.; Manoochehri, K.; Rovins, J.; Beale, J.; Barr, B.

    1985-01-01

    Several areas that arise from the system integration issue were examined. Intersystem analysis is discussed as it relates to software development, shared data bases and interfaces between TEMPUS and PLAID, shaded graphics rendering systems, object design (BUILD), the TEMPUS animation system, anthropometric lab integration, ongoing TEMPUS support and maintenance, and the impact of UNIX and local workstations on the OSDS environment.

  18. Lofar information system design

    NARCIS (Netherlands)

    Valentijn, E.; Belikov, A. N.

    2009-01-01

    The Lofar Information System is a solution for Lofar Long Term Archive that is capable to store and handle PBs of raw and processed data. The newly created information system is based on Astro-WISE - the information system for wide field astronomy. We review an adaptation of Astro-WISE for the new t

  19. Development Expert System

    Institute of Scientific and Technical Information of China (English)

    CAI Heng

    2010-01-01

    The expert system is a high-level technology.It is a sub-field of artificial intelligence.We demonstrated the character and software evaluation,carrying out an initial study of expert system.A good development expert system was developed.

  20. Controllability of Quantum Systems

    CERN Document Server

    Schirmer, S G; Solomon, A I

    2003-01-01

    An overview and synthesis of results and criteria for open-loop controllability of Hamiltonian quantum systems obtained using Lie group and Lie algebra techniques is presented. Negative results for open-loop controllability of dissipative systems are discussed, and the superiority of closed-loop (feedback) control for quantum systems is established.

  1. LED system reliability

    NARCIS (Netherlands)

    Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.

    2011-01-01

    This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific ex

  2. Personal Food System Mapping

    Science.gov (United States)

    Wilsey, David; Dover, Sally

    2014-01-01

    Personal food system mapping is a practical means to engage community participants and educators in individualized and shared learning about food systems, decisions, and behaviors. Moreover, it is a useful approach for introducing the food system concept, which is somewhat abstract. We developed the approach to capture diversity of personal food…

  3. Endocrine System (For Parents)

    Science.gov (United States)

    ... of or replacing specific hormones can treat many endocrine disorders in children and adolescents, some of which include: ... System Your Child's Growth Female Reproductive System Activity: Endocrine System Word! Hormones Diabetes Center Thyroid Disorders Type 2 Diabetes: What Is It? Your Endocrine ...

  4. Control Oriented System Identification

    Science.gov (United States)

    1993-08-01

    The research goals for this grant were to obtain algorithms for control oriented system identification is to construct dynamical models of systems...and measured information. Algorithms for this type of nonlinear system identification have been given that produce models suitable for gain scheduled

  5. Building Community Knowledge Systems

    DEFF Research Database (Denmark)

    Bansler, Jørgen P.; Havn, Erling C.

    2003-01-01

    managers. We followed the system from its introduction in early 1997 until it was abandoned in the beginning of 2000. We focused on the way the system was introduced in the organization, how it changed, and how the intended group of users received (and eventually rejected) the system. Based on our...

  6. Medical Information Systems.

    Science.gov (United States)

    Smith, Kent A.

    1986-01-01

    Description of information services from the National Library of Medicine (NLM) highlights a new system for retrieving information from NLM's databases (GRATEFUL MED); a formal Regional Medical Library Network; DOCLINE; the Unified Medical Language System; and Integrated Academic Information Management Systems. Research and development and the…

  7. Controllability in nonlinear systems

    Science.gov (United States)

    Hirschorn, R. M.

    1975-01-01

    An explicit expression for the reachable set is obtained for a class of nonlinear systems. This class is described by a chain condition on the Lie algebra of vector fields associated with each nonlinear system. These ideas are used to obtain a generalization of a controllability result for linear systems in the case where multiplicative controls are present.

  8. The Quality System

    DEFF Research Database (Denmark)

    Brogaard Buus, Daniel; Eland, Morten Vestergaard; Lystlund, Rasmus

    2015-01-01

    In this article, we present our efforts to try to increase cohesiveness and connectivity between quests generated by a recreation of an existing procedural quest generation system, with an addition of a progressive tier system called Quality System. A study gave strong indications that the Quality...

  9. LOFAR Information System

    NARCIS (Netherlands)

    Begeman, K.; Belikov, A. N.; Boxhoorn, D. R.; Dijkstra, F.; Holties, H.; Meyer-Zhao, Z.; Renting, G. A.; Valentijn, E. A.; Vriend, W. -J.

    2011-01-01

    In this paper, we present a newly designed and implemented scientific information system for the LOFAR Long Term Archive. It is a distributed multi-tier storage and data processing system that allows a number of users to process Petabytes of data. The LOFAR Information System is designed on the base

  10. Imaging systems and applications.

    Science.gov (United States)

    Catrysse, Peter B; Imai, Francisco H; Linne von Berg, Dale C; Sheridan, John T

    2013-03-01

    Imaging systems have numerous applications in industrial, military, consumer, and medical settings. Assembling a complete imaging system requires the integration of optics, sensing, image processing, and display rendering. This issue features original research ranging from fundamental theories to novel imaging modalities and provides a systems perspective to imaging.

  11. Flexible energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    The paper discusses and analyses diffent national strategies and points out key changes in the energy system in order to achieve a system which can benefit from a high percentage of wind and CHP without having surplus production problems, introduced here as a flexible energy system....

  12. IDC System Specification Document.

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, David J.

    2014-12-01

    This document contains the system specifications derived to satisfy the system requirements found in the IDC System Requirements Document for the IDC Reengineering Phase 2 project. Revisions Version Date Author/Team Revision Description Authorized by V1.0 12/2014 IDC Reengineering Project Team Initial delivery M. Harris

  13. Energy systems security

    CERN Document Server

    Voeller, John G

    2014-01-01

    Energy Systems Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to electricity transmission grids and their protection, risk assessment of energy systems, analysis of interdependent energy networks. Methods to manage electricity transmission disturbances so as to avoid blackouts are discussed, and self-healing energy system and a nano-enabled power source are presented.

  14. Types of Data Systems

    Science.gov (United States)

    Gould, Tate; Nicholas, Amy; Ruggiero, Tony; Blandford, William; Thayer, Sara; Bull, Bruce

    2015-01-01

    There are several types of data systems that support data from Part C/619 programs. Although the system types have similarities, each has its own unique characteristics and purposes. The attributes that make one type of data system a particularly good fit for one data-related need or function can be less desirable for another need or function. In…

  15. The complement system in systemic autoimmune disease.

    Science.gov (United States)

    Chen, Min; Daha, Mohamed R; Kallenberg, Cees G M

    2010-05-01

    Complement is part of the innate immune system. Its major function is recognition and elimination of pathogens via direct killing and/or stimulation of phagocytosis. Activation of the complement system is, however, also involved in the pathogenesis of the systemic autoimmune diseases. Activation via the classical pathway has long been recognized in immune complex-mediated diseases such as cryoglobulinemic vasculitis and systemic lupus erythematosus (SLE). In SLE, the role of complement is somewhat paradoxical. It is involved in autoantibody-initiated tissue damage on the one hand, but, on the other hand, it appears to have protective features as hereditary deficiencies of classical pathway components are associated with an increased risk for SLE. There is increasing evidence that the alternative pathway of complement, even more than the classical pathway, is involved in many systemic autoimmune diseases. This is true for IgA-dominant Henoch Schönlein Purpura, in which additional activation of the lectin pathway contributes to more severe disease. In anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis the complement system was considered not to be involved since immunoglobulin deposition is generally absent in the lesions. However, recent studies, both in human and animal models, demonstrated complement activation via the alternative pathway as a major pathogenic mechanism. Insight into the role of the various pathways of complement in the systemic autoimmune diseases including the vasculitides opens up new ways of treatment by blocking effector pathways of complement. This has been demonstrated for monoclonal antibodies to C5 or C5a in experimental anti-phospholipid antibody syndrome and ANCA-associated vasculitis.

  16. Petascale system management experiences.

    Energy Technology Data Exchange (ETDEWEB)

    Desai, N.; Bradshaw, R.; Lueninghoener, C.; Cherry, A.; Coghlan, S.; Scullin, W. (LCF); ( MCS)

    2008-01-01

    Petascale High-Performance Computing (HPC) systems are among the largest systems in the world. Intrepid, one such system, is a 40,000 node, 556 teraflop Blue Gene/P system that has been deployed at Argonne National Laboratory. In this paper, we provide some background about the system and our administration experiences. In particular, due to the scale of the system, we have faced a variety of issues, some surprising to us, that are not common in the commodity world. We discuss our expectations, these issues, and approaches we have used to address them. HPC systems are a bellwether for computing systems at large, in multiple regards. HPC users are motivated by the need for absolute performance; this results in two important pushes. HPC users are frequently early adopters of new technologies and techniques. Successful technologies, like Infiniband, prove their value in HPC before gaining wider adoption. Unfortunately, this early adoption alone is not sufficient to achieve the levels of performance required by HPC users; parallelism must also be harnessed. Over the last 15 years, beowulf clustering has provided amazing accessibility to non-HPC-savvy and even non-technical audiences. During this time, substantial adoption of clustering has occurred in many market segments unrelated to computational science. A simple trend has emerged: the scale and performance of high-end HPC systems are uncommon at first, but become commonplace over the course of 3-5 years. For example, in early 2003, several systems on the Top500 list consisted of either 1024 nodes or 4096-8192 cores. In 2008, such systems are commonplace. The most recent generation of high-end HPC systems, so called petascale systems, are the culmination of years of research and development in research and academia. Three such systems have been deployed thus far. In addition to the 556 TF Intrepid system at Argonne National Laboratory, a 596 TF Blue Gene/L-based system has been deployed at Lawrence Livermore

  17. Power system relaying

    CERN Document Server

    Horowitz, Stanley H; Niemira, James K

    2013-01-01

    The previous three editions of Power System Relaying offer comprehensive and accessible coverage of the theory and fundamentals of relaying and have been widely adopted on university and industry courses worldwide. With the third edition, the authors have added new and detailed descriptions of power system phenomena such as stability, system-wide protection concepts and discussion of historic outages. Power System Relaying, 4th Edition continues its role as an outstanding textbook on power system protection for senior and graduate students in the field of electric power engineering and a refer

  18. Superconductor rotor cooling system

    Science.gov (United States)

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2002-01-01

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  19. Building Web Reputation Systems

    CERN Document Server

    Farmer, Randy

    2010-01-01

    What do Amazon's product reviews, eBay's feedback score system, Slashdot's Karma System, and Xbox Live's Achievements have in common? They're all examples of successful reputation systems that enable consumer websites to manage and present user contributions most effectively. This book shows you how to design and develop reputation systems for your own sites or web applications, written by experts who have designed web communities for Yahoo! and other prominent sites. Building Web Reputation Systems helps you ask the hard questions about these underlying mechanisms, and why they're critical

  20. Dynamical Systems Conference

    CERN Document Server

    Gils, S; Hoveijn, I; Takens, F; Nonlinear Dynamical Systems and Chaos

    1996-01-01

    Symmetries in dynamical systems, "KAM theory and other perturbation theories", "Infinite dimensional systems", "Time series analysis" and "Numerical continuation and bifurcation analysis" were the main topics of the December 1995 Dynamical Systems Conference held in Groningen in honour of Johann Bernoulli. They now form the core of this work which seeks to present the state of the art in various branches of the theory of dynamical systems. A number of articles have a survey character whereas others deal with recent results in current research. It contains interesting material for all members of the dynamical systems community, ranging from geometric and analytic aspects from a mathematical point of view to applications in various sciences.

  1. Benchmarking expert system tools

    Science.gov (United States)

    Riley, Gary

    1988-01-01

    As part of its evaluation of new technologies, the Artificial Intelligence Section of the Mission Planning and Analysis Div. at NASA-Johnson has made timing tests of several expert system building tools. Among the production systems tested were Automated Reasoning Tool, several versions of OPS5, and CLIPS (C Language Integrated Production System), an expert system builder developed by the AI section. Also included in the test were a Zetalisp version of the benchmark along with four versions of the benchmark written in Knowledge Engineering Environment, an object oriented, frame based expert system tool. The benchmarks used for testing are studied.

  2. A distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Jaerventausta, P.; Verho, P.; Kaerenlampi, M.; Pitkaenen, M. [Tampere Univ. of Technology (Finland); Partanen, J. [Lappeenranta Univ. of Technology (Finland)

    1998-08-01

    The development of new distribution automation applications is considerably wide nowadays. One of the most interesting areas is the development of a distribution management system (DMS) as an expansion to the traditional SCADA system. At the power transmission level such a system is called an energy management system (EMS). The idea of these expansions is to provide supporting tools for control center operators in system analysis and operation planning. Nowadays the SCADA is the main computer system (and often the only) in the control center. However, the information displayed by the SCADA is often inadequate, and several tasks cannot be solved by a conventional SCADA system. A need for new computer applications in control center arises from the insufficiency of the SCADA and some other trends. The latter means that the overall importance of the distribution networks is increasing. The slowing down of load-growth has often made network reinforcements unprofitable. Thus the existing network must be operated more efficiently. At the same time larger distribution areas are for economical reasons being monitored at one control center and the size of the operation staff is decreasing. The quality of supply requirements are also becoming stricter. The needed data for new applications is mainly available in some existing systems. Thus the computer systems of utilities must be integrated. The main data source for the new applications in the control center are the AM/FM/GIS (i.e. the network database system), the SCADA, and the customer information system (CIS). The new functions can be embedded in some existing computer system. This means a strong dependency on the vendor of the existing system. An alternative strategy is to develop an independent system which is integrated with other computer systems using well-defined interfaces. The latter approach makes it possible to use the new applications in various computer environments, having only a weak dependency on the

  3. Liver in systemic disease

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Potential causes of abnormal liver function tests include viral hepatitis, alcohol intake, nonalcoholic fatty liver disease, autoimmune liver diseases, hereditary diseases, hepatobiliary malignancies or infection, gallstones and drug-induced liver injury. Moreover, the liver may be involved in systemic diseases that mainly affect other organs. Therefore, in patients without etiology of liver injury by screening serology and diagnostic imaging, but who have systemic diseases, the abnormal liver function test results might be caused by the systemic disease. In most of these patients, the systemic disease should be treated primarily. However, some patients with systemic disease and severe liver injury or fulminant hepatic failure require intensive treatments of the liver.

  4. Power system state estimation

    CERN Document Server

    Ahmad, Mukhtar

    2012-01-01

    State estimation is one of the most important functions in power system operation and control. This area is concerned with the overall monitoring, control, and contingency evaluation of power systems. It is mainly aimed at providing a reliable estimate of system voltages. State estimator information flows to control centers, where critical decisions are made concerning power system design and operations. This valuable resource provides thorough coverage of this area, helping professionals overcome challenges involving system quality, reliability, security, stability, and economy.Engineers are

  5. Calculus for decision systems

    OpenAIRE

    Samayoa Ranero, Jorge Antonio

    2015-01-01

    The conceptualization of the term "system" has become highly dependent on the application domain. What a physicist means by the term system might be different than what a sociologist means by the same term. In 1956, Bertalanffy [1] defined a system as " a set of units with relationships among them". This and many other definitions of system share the idea of a system as a black box that has parts or elements interacting between each other. This means that at some level of abstraction all syst...

  6. Electric power systems

    CERN Document Server

    Weedy, B M; Jenkins, N; Ekanayake, J B; Strbac, G

    2012-01-01

    The definitive textbook for Power Systems students, providing a grounding in essential power system theory while also focusing on practical power engineering applications. Electric Power Systems has been an essential book in power systems engineering for over thirty years. Bringing the content firmly up-to-date whilst still retaining the flavour of Weedy's extremely popular original, this Fifth Edition has been revised by experts Nick Jenkins, Janaka Ekanayake and Goran Strbac. This wide-ranging text still covers all of the fundamental power systems subjects but is now e

  7. SNS Cryogenic Systems Commissioning

    Energy Technology Data Exchange (ETDEWEB)

    D. Hatfield; F. Casagrande; I. Campisi; P. Gurd; M. Howell; D. Stout; H. Strong; D. Arenius; J. Creel; K. Dixon; V. Ganni; and P. Knudsen

    2005-08-29

    The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.

  8. [Automated anesthesia record system].

    Science.gov (United States)

    Zhu, Tao; Liu, Jin

    2005-12-01

    Based on Client/Server architecture, a software of automated anesthesia record system running under Windows operation system and networks has been developed and programmed with Microsoft Visual C++ 6.0, Visual Basic 6.0 and SQL Server. The system can deal with patient's information throughout the anesthesia. It can collect and integrate the data from several kinds of medical equipment such as monitor, infusion pump and anesthesia machine automatically and real-time. After that, the system presents the anesthesia sheets automatically. The record system makes the anesthesia record more accurate and integral and can raise the anesthesiologist's working efficiency.

  9. Information systems project management

    CERN Document Server

    Olson, David

    2014-01-01

    Information Systems Project Management addresses project management in the context of information systems. It deals with general project management principles, with focus on the special characteristics of information systems. It is based on an earlier text, but shortened to focus on essential project management elements.This updated version presents various statistics indicating endemic problems in completing information system projects on time, within budget, at designed functionality. While successful completion of an information systems project is a challenge, there are some things that ca

  10. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS (A Toroidal LHC Apparatus). The ALFA system is composed by four stations installed in the LHC tunnel 240 m away from the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronics for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  11. SNS Cryogenic Systems Commissioning

    Science.gov (United States)

    Hatfield, D.; Casagrande, F.; Campisi, I.; Gurd, P.; Howell, M.; Stout, D.; Strong, H.; Arenius, D.; Creel, J.; Dixon, K.; Ganni, V.; Knudsen, P.

    2006-04-01

    The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.

  12. Intelligent Car System

    Directory of Open Access Journals (Sweden)

    Qasim Siddique

    2009-01-01

    Full Text Available In modern life the road safety has becomes the core issue. One single move of a driver can cause horrifying accident. The main goal of intelligent car system is to make communication with other cars on the road. The system is able to control to speed, direction and the distance between the cars the intelligent car system is able to recognize traffic light and is able to take decision according to it. This paper presents a framework of the intelligent car system. I validate several aspect of our system using simulation.

  13. Intelligent Car System

    CERN Document Server

    Siddique, Qasim

    2012-01-01

    In modern life the road safety has becomes the core issue. One single move of a driver can cause horrifying accident. The main goal of intelligent car system is to make communication with other cars on the road. The system is able to control to speed, direction and the distance between the cars the intelligent car system is able to recognize traffic light and is able to take decision according to it. This paper presents a framework of the intelligent car system. I validate several aspect of our system using simulation.

  14. CNEOST Control Software System

    Science.gov (United States)

    Wang, X.; Zhao, H. B.; Xia, Y.; Lu, H.; Li, B.

    2015-03-01

    In 2013, CNEOST (China Near Earth Object Survey Telescope) adapted its hardware system for the new CCD camera. Based on the new system architecture, the control software is re-designed and implemented. The software system adopts the message passing mechanism via WebSocket protocol, and improves its flexibility, expansibility, and scalability. The user interface with responsive web design realizes the remote operating under both desktop and mobile devices. The stable operating of software system has greatly enhanced the operation efficiency while reducing the complexity, and has also made a successful attempt for the future system design of telescope and telescope cloud.

  15. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS/LHC. The ALFA system is composed by two stations installed in the LHC tunnel 240 m away from each side of the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronic for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  16. Leakage resilient password systems

    CERN Document Server

    Li, Yingjiu; Deng, Robert H

    2015-01-01

    This book investigates tradeoff between security and usability in designing leakage resilient password systems (LRP) and introduces two practical LRP systems named Cover Pad and ShadowKey. It demonstrates that existing LRP systems are subject to both brute force attacks and statistical attacks and that these attacks cannot be effectively mitigated without sacrificing the usability of LRP systems. Quantitative analysis proves that a secure LRP system in practical settings imposes a considerable amount of cognitive workload unless certain secure channels are involved. The book introduces a secur

  17. THERMAL DISTRIBUTION SYSTEM EXPERIMENT

    Energy Technology Data Exchange (ETDEWEB)

    KRAJEWSKI,R.F.; ANDREWS,J.W.; WEI,G.

    1999-09-01

    A laboratory experiment has been conducted which tests for the effects of distribution system purging on system Delivery Effectiveness (DE) as defined in ASHRAE 152P. The experiment is described in its configuration, instrumentation, and data acquisition system. Data gathered in the experiment is given and discussed. The results show that purging of the distribution system alone does not offer any improvement of the system DE. Additional supporting tests were conducted regarding experimental simulations of buffer zones and bare pipe and are also discussed.

  18. SYSTEMS ENGINEERING RESEARCH

    Institute of Scientific and Technical Information of China (English)

    Abd-El-Kader SAHRAOUI; Dennis M. BUEDE; Andrew P. SAGE

    2008-01-01

    In this paper, we propose selected research topics that are believed central to progress and growth in the application of systems engineering (SE). As a professional activity, and as an intellectual activity, systems engineering has strong links to such associated disciplines as decision analysis, operation research, project management, quality management, and systems design. When focussing on systems engineering research, we should distinguish between subjects that are of systems engineering essence and others that more closely correspond to those that are more relevant for related disciplines.

  19. 2014 Runtime Systems Summit. Runtime Systems Report

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Vivek [US Dept. of Energy, Washington, DC (United States); Budimlic, Zoran [US Dept. of Energy, Washington, DC (United States); Kulkani, Milind [US Dept. of Energy, Washington, DC (United States)

    2016-09-19

    This report summarizes runtime system challenges for exascale computing, that follow from the fundamental challenges for exascale systems that have been well studied in past reports, e.g., [6, 33, 34, 32, 24]. Some of the key exascale challenges that pertain to runtime systems include parallelism, energy efficiency, memory hierarchies, data movement, heterogeneous processors and memories, resilience, performance variability, dynamic resource allocation, performance portability, and interoperability with legacy code. In addition to summarizing these challenges, the report also outlines different approaches to addressing these significant challenges that have been pursued by research projects in the DOE-sponsored X-Stack and OS/R programs. Since there is often confusion as to what exactly the term “runtime system” refers to in the software stack, we include a section on taxonomy to clarify the terminology used by participants in these research projects. In addition, we include a section on deployment opportunities for vendors and government labs to build on the research results from these projects. Finally, this report is also intended to provide a framework for discussing future research and development investments for exascale runtime systems, and for clarifying the role of runtime systems in exascale software.

  20. Exploration EVA System

    Science.gov (United States)

    Kearney, Lara

    2004-01-01

    In January 2004, the President announced a new Vision for Space Exploration. NASA's Office of Exploration Systems has identified Extravehicular Activity (EVA) as a critical capability for supporting the Vision for Space Exploration. EVA is required for all phases of the Vision, both in-space and planetary. Supporting the human outside the protective environment of the vehicle or habitat and allow ing him/her to perform efficient and effective work requires an integrated EVA "System of systems." The EVA System includes EVA suits, airlocks, tools and mobility aids, and human rovers. At the core of the EVA System is the highly technical EVA suit, which is comprised mainly of a life support system and a pressure/environmental protection garment. The EVA suit, in essence, is a miniature spacecraft, which combines together many different sub-systems such as life support, power, communications, avionics, robotics, pressure systems and thermal systems, into a single autonomous unit. Development of a new EVA suit requires technology advancements similar to those required in the development of a new space vehicle. A majority of the technologies necessary to develop advanced EVA systems are currently at a low Technology Readiness Level of 1-3. This is particularly true for the long-pole technologies of the life support system.

  1. System level ESD protection

    CERN Document Server

    Vashchenko, Vladislav

    2014-01-01

    This book addresses key aspects of analog integrated circuits and systems design related to system level electrostatic discharge (ESD) protection.  It is an invaluable reference for anyone developing systems-on-chip (SoC) and systems-on-package (SoP), integrated with system-level ESD protection. The book focuses on both the design of semiconductor integrated circuit (IC) components with embedded, on-chip system level protection and IC-system co-design. The readers will be enabled to bring the system level ESD protection solutions to the level of integrated circuits, thereby reducing or completely eliminating the need for additional, discrete components on the printed circuit board (PCB) and meeting system-level ESD requirements. The authors take a systematic approach, based on IC-system ESD protection co-design. A detailed description of the available IC-level ESD testing methods is provided, together with a discussion of the correlation between IC-level and system-level ESD testing methods. The IC-level ESD...

  2. Active optical zoom system

    Science.gov (United States)

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  3. TPC magnet cryogenic system

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.A.; Burns, W.A.; Taylor, J.D.; Van Slyke, H.W.

    1980-03-01

    The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar (for liquid nitrogen). The operation o these systems during virtually all phases of system operation are described. Photographs and diagrams of various system components are shown, and cryogenic system data are presented in the following sections: (1) heat leaks into the TPC coil package and the compensation solenoids; (2) heat leaks to various components of the TPC magnet cryogenics system besides the magnets and control dewar; (3) the control dewar and its relationship to the rest of the system; (4) the conditioner system and its role in cooling down the TPC magnet; (5) gas-cooled electrical leads and charging losses; and (6) a summation of the liquid helium and liquid nitrogen requirements for the TPC superconducting magnet system.

  4. Space Nuclear Power Systems

    Science.gov (United States)

    Houts, Michael G.

    2012-01-01

    Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

  5. Thermodynamics of Nonadditive Systems.

    Science.gov (United States)

    Latella, Ivan; Pérez-Madrid, Agustín; Campa, Alessandro; Casetti, Lapo; Ruffo, Stefano

    2015-06-12

    The usual formulation of thermodynamics is based on the additivity of macroscopic systems. However, there are numerous examples of macroscopic systems that are not additive, due to the long-range character of the interaction among the constituents. We present here an approach in which nonadditive systems can be described within a purely thermodynamics formalism. The basic concept is to consider a large ensemble of replicas of the system where the standard formulation of thermodynamics can be naturally applied and the properties of a single system can be consequently inferred. After presenting the approach, we show its implementation in systems where the interaction decays as 1/r(α) in the interparticle distance r, with α smaller than the embedding dimension d, and in the Thirring model for gravitational systems.

  6. Multisource energy system project

    Science.gov (United States)

    Dawson, R. W.; Cowan, R. A.

    1987-03-01

    The mission of this project is to investigate methods of providing uninterruptible power to Army communications and navigational facilities, many of which have limited access or are located in rugged terrain. Two alternatives are currently available for deploying terrestrial stand-alone power systems: (1) conventional electric systems powered by diesel fuel, propane, or natural gas, and (2) alternative power systems using renewable energy sources such as solar photovoltaics (PV) or wind turbines (WT). The increased cost of fuels for conventional systems and the high cost of energy storage for single-source renewable energy systems have created interest in the hybrid or multisource energy system. This report will provide a summary of the first and second interim reports, final test results, and a user's guide for software that will assist in applying and designing multi-source energy systems.

  7. System floorplanning optimization

    KAUST Repository

    Browning, David W.

    2013-01-10

    Notebook and Laptop Original Equipment Manufacturers (OEMs) place great emphasis on creating unique system designs to differentiate themselves in the mobile market. These systems are developed from the \\'outside in\\' with the focus on how the system is perceived by the end-user. As a consequence, very little consideration is given to the interconnections or power of the devices within the system with a mentality of \\'just make it fit\\'. In this paper we discuss the challenges of Notebook system design and the steps by which system floor-planning tools and algorithms can be used to provide an automated method to optimize this process to ensure all required components most optimally fit inside the Notebook system.

  8. MDT DCS Electronics System

    CERN Document Server

    Tsarouchas, Charilaos; Gazis, Evangelos; Tsipolitis, Georgios

    This note has the aim to present the Detector Control System for the Monitor- ing of the electronics values of MDT chambers in ATLAS experiment in CERN. This system is decided to be called in short ELTX. The principal task of DCS is to enable and ensure the coherent and safe oper- ation of the detector. The interaction of detector expers, users or shifters to the detector hardware is also done via DCS. This is the responsible system of moni- toring the operational parameters and the overall state of the detector, the alarm generation and handling, the connection of hardware values to databases and the interaction with the DAQ system. Through this thesis, one can see what ELTX system has to offer as a Detector Control System and in detail, what is the hardware to be controlled and monitored. Moreover it is presented the mainstream of central Atlas DCS concerning the active interfaces.ELTX is a system following these standards.

  9. Synchronization of chaotic systems.

    Science.gov (United States)

    Pecora, Louis M; Carroll, Thomas L

    2015-09-01

    We review some of the history and early work in the area of synchronization in chaotic systems. We start with our own discovery of the phenomenon, but go on to establish the historical timeline of this topic back to the earliest known paper. The topic of synchronization of chaotic systems has always been intriguing, since chaotic systems are known to resist synchronization because of their positive Lyapunov exponents. The convergence of the two systems to identical trajectories is a surprise. We show how people originally thought about this process and how the concept of synchronization changed over the years to a more geometric view using synchronization manifolds. We also show that building synchronizing systems leads naturally to engineering more complex systems whose constituents are chaotic, but which can be tuned to output various chaotic signals. We finally end up at a topic that is still in very active exploration today and that is synchronization of dynamical systems in networks of oscillators.

  10. Quantum system identification.

    Science.gov (United States)

    Burgarth, Daniel; Yuasa, Kazuya

    2012-02-24

    The aim of quantum system identification is to estimate the ingredients inside a black box, in which some quantum-mechanical unitary process takes place, by just looking at its input-output behavior. Here we establish a basic and general framework for quantum system identification, that allows us to classify how much knowledge about the quantum system is attainable, in principle, from a given experimental setup. We show that controllable closed quantum systems can be estimated up to unitary conjugation. Prior knowledge on some elements of the black box helps the system identification. We present an example in which a Bell measurement is more efficient to identify the system. When the topology of the system is known, the framework enables us to establish a general criterion for the estimability of the coupling constants in its Hamiltonian.

  11. Discrete Control Systems

    CERN Document Server

    Lee, Taeyoung; McClamroch, N Harris

    2007-01-01

    Discrete control systems, as considered here, refer to the control theory of discrete-time Lagrangian or Hamiltonian systems. These discrete-time models are based on a discrete variational principle, and are part of the broader field of geometric integration. Geometric integrators are numerical integration methods that preserve geometric properties of continuous systems, such as conservation of the symplectic form, momentum, and energy. They also guarantee that the discrete flow remains on the manifold on which the continuous system evolves, an important property in the case of rigid-body dynamics. In nonlinear control, one typically relies on differential geometric and dynamical systems techniques to prove properties such as stability, controllability, and optimality. More generally, the geometric structure of such systems plays a critical role in the nonlinear analysis of the corresponding control problems. Despite the critical role of geometry and mechanics in the analysis of nonlinear control systems, non...

  12. System floorplanning optimization

    KAUST Repository

    Browning, David W.

    2012-12-01

    Notebook and Laptop Original Equipment Manufacturers (OEMs) place great emphasis on creating unique system designs to differentiate themselves in the mobile market. These systems are developed from the \\'outside in\\' with the focus on how the system is perceived by the end-user. As a consequence, very little consideration is given to the interconnections or power of the devices within the system with a mentality of \\'just make it fit\\'. In this paper we discuss the challenges of Notebook system design and the steps by which system floor-planning tools and algorithms can be used to provide an automated method to optimize this process to ensure all required components most optimally fit inside the Notebook system. © 2012 IEEE.

  13. Ubiquitous Annotation Systems

    DEFF Research Database (Denmark)

    Hansen, Frank Allan

    2006-01-01

    Ubiquitous annotation systems allow users to annotate physical places, objects, and persons with digital information. Especially in the field of location based information systems much work has been done to implement adaptive and context-aware systems, but few efforts have focused on the general...... requirements for linking information to objects in both physical and digital space. This paper surveys annotation techniques from open hypermedia systems, Web based annotation systems, and mobile and augmented reality systems to illustrate different approaches to four central challenges ubiquitous annotation...... systems have to deal with: anchoring, structuring, presentation, and authoring. Through a number of examples each challenge is discussed and HyCon, a context-aware hypermedia framework developed at the University of Aarhus, Denmark, is used to illustrate an integrated approach to ubiquitous annotations...

  14. The ALHAMBRA photometric system

    CERN Document Server

    Villegas, T Aparicio; Cabrera-Cano, J; Moles, M; Benitez, N; Perea, J; del Olmo, A; Fernandez-Soto, A; Cristobal-Hornillos, D; Husillos, C; Aguerri, J A L; Broadhurst, T; Castander, F J; Cepa, J; Cervino, M; Delgado, R M Gonzalez; Infante, L; Marquez, I; Masegosa, J; Martinez, V J; Prada, F; Quintana, J M; Sanchez, S F

    2010-01-01

    This paper presents the characterization of the optical range of the ALHAMBRA photometric system, a 20 contiguous, equal-width, medium-band CCD system with wavelength coverage from 3500A to 9700A. The photometric description of the system is done by presenting the full response curve as a product of the filters, CCD and atmospheric transmission curves, and using some first and second order moments of this response function. We also introduce the set of standard stars that defines the system, formed by 31 classic spectrophotometric standard stars which have been used in the calibration of other known photometric systems, and 288 stars, flux calibrated homogeneously, from the Next Generation Spectral Library (NGSL). Based on the NGSL, we determine the transformation equations between Sloan Digital Sky Survey (SDSS) ugriz photometry and the ALHAMBRA photometric system, in order to establish some relations between both systems. Finally we develop and discuss a strategy to calculate the photometric zero points of ...

  15. Beam Synchronous Timing Systems

    CERN Document Server

    Peters, A

    2003-01-01

    For many beam diagnostics purposes beam synchronous timing systems are needed in addition to the timing systems supplied by the control systems of the different accelerators. The demands and techniques of different accelerator facilities will be discussed along the following aspects: Bunch and macro pulse synchronous timing systems Solutions for different time scales from ps to ms Coupling to the RF and control systems of the different accelerators Electronics for the beam synchronous timing systems: parameters, techniques, controlling Use of industrial products for bunch synchronous timing systems, e.g. function generators Distribution of the timing signals: electronically via cables, optically via fibres or wireless Coupling to and use of timing standards: IRIG-B, GPS, ? The participants should present and describe solutions from their facilities with some transparencies as a starting point for the discussion.

  16. Systems engineering and analysis

    CERN Document Server

    Blanchard, Benjamin S

    2010-01-01

    For senior-level undergraduate and first and second year graduate systems engineering and related courses. A total life-cycle approach to systems and their analysis. This practical introduction to systems engineering and analysis provides the concepts, methodologies, models, and tools needed to understand and implement a total life-cycle approach to systems and their analysis. The authors focus first on the process of bringing systems into being--beginning with the identification of a need and extending that need through requirements determination, functional analysis and allocation, design synthesis, evaluation, and validation, operation and support, phase-out, and disposal. Next, the authors discuss the improvement of systems currently in being, showing that by employing the iterative process of analysis, evaluation, feedback, and modification, most systems in existence can be improved in their affordability, effectiveness, and stakeholder satisfaction.

  17. Synchronization of chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Pecora, Louis M.; Carroll, Thomas L. [U.S. Naval Research Laboratory, Washington, District of Columbia 20375 (United States)

    2015-09-15

    We review some of the history and early work in the area of synchronization in chaotic systems. We start with our own discovery of the phenomenon, but go on to establish the historical timeline of this topic back to the earliest known paper. The topic of synchronization of chaotic systems has always been intriguing, since chaotic systems are known to resist synchronization because of their positive Lyapunov exponents. The convergence of the two systems to identical trajectories is a surprise. We show how people originally thought about this process and how the concept of synchronization changed over the years to a more geometric view using synchronization manifolds. We also show that building synchronizing systems leads naturally to engineering more complex systems whose constituents are chaotic, but which can be tuned to output various chaotic signals. We finally end up at a topic that is still in very active exploration today and that is synchronization of dynamical systems in networks of oscillators.

  18. Continuous recovery system for electrorefiner system

    Science.gov (United States)

    Williamson, Mark A.; Wiedmeyer, Stanley G.; Willit, James L.; Barnes, Laurel A.; Blaskovitz, Robert J.

    2014-06-10

    A continuous recovery system for an electrorefiner system may include a trough having a ridge portion and a furrow portion. The furrow portion may include a first section and a second section. An inlet and exit pipe may be connected to the trough. The inlet pipe may include an outlet opening that opens up to the first section of the furrow portion of the trough. The exit pipe may include an entrance opening that opens up to the second section of the furrow portion of the trough. A chain may extend through the inlet and exit pipes and along the furrow portion of the trough. The chain may be in a continuous loop form. A plurality of flights may be secured to the chain. Accordingly, the desired product may be continuously harvested from the electrorefiner system without having to halt the electrical power and/or remove the cathode and anode assemblies.

  19. Immune System Inspired Strategies for Distributed Systems

    CERN Document Server

    Banerjee, Soumya

    2010-01-01

    Many components of the IS are constructed as modular units which do not need to communicate with each other such that the number of components increases but the size remains constant. However, a sub-modular IS architecture in which lymph node number and size both increase sublinearly with body size is shown to efficiently balance the requirements of communication and migration, consistent with experimental data. We hypothesize that the IS architecture optimizes the tradeoff between local search for pathogens and global response using antibodies. Similar to natural immune systems, physical space and resource are also important constraints on Artificial Immune Systems (AIS), especially distributed systems applications used to connect low-powered sensors using short-range wireless communication. AIS problems like distributed robot control will also require a sub-modular architecture to efficiently balance the tradeoff between local search for a solution and global response or proliferation of the solution betwee...

  20. Automated Information System (AIS) Alarm System

    Energy Technology Data Exchange (ETDEWEB)

    Hunteman, W.

    1997-05-01

    The Automated Information Alarm System is a joint effort between Los Alamos National Laboratory, Lawrence Livermore National Laboratory, and Sandia National Laboratory to demonstrate and implement, on a small-to-medium sized local area network, an automated system that detects and automatically responds to attacks that use readily available tools and methodologies. The Alarm System will sense or detect, assess, and respond to suspicious activities that may be detrimental to information on the network or to continued operation of the network. The responses will allow stopping, isolating, or ejecting the suspicious activities. The number of sensors, the sensitivity of the sensors, the assessment criteria, and the desired responses may be set by the using organization to meet their local security policies.