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Sample records for agents stimulating erythropoiesis

  1. Pharmacovigilance in practice: erythropoiesis-stimulating agents

    International Nuclear Information System (INIS)

    Pharmacovigilance (PV) is the science and activities relating to the detection, assessment, understanding, and prevention of adverse effects or other problems related to medical products after they have been licensed for marketing. The purpose of PV is to advance the safe use of marketed medical products. Regulatory agencies and license holders collaborate to collect data reported by health care providers, patients, and the public as well as data from systematic reviews, meta-analyses, and individual clinical and nonclinical studies. They validate and analyze the data to determine whether safety signals exist, and if warranted, develop an action plan to mitigate the identified risk. Erythropoiesis-stimulating agents (ESAs) provide an example of how PV is applied in reality. Among other approved indications, ESAs may be used to treat anemia in patients with chemotherapy-induced anemia. ESAs increase hemoglobin levels and reduce the need for transfusions; they are also associated with a known increased risk of thromboembolic events. Starting in 2003, emerging data suggested that ESAs might reduce survival. As a result of PV activities by regulatory agencies and license holders, labeling for ESAs addresses these risks. Meta-analyses and individual clinical studies have confirmed that ESAs increase the risk of thromboembolic events, but when used as indicated, ESAs have not been shown to have a significant effect on survival or disease progression. Ongoing safety studies will provide additional data in the coming years to further clarify the risks and benefits of ESAs

  2. Iron and erythropoiesis-stimulating agents in anaemia

    Directory of Open Access Journals (Sweden)

    Thomas Rath

    2010-01-01

    Full Text Available Anaemia is a frequent and clinically relevant problem in patients with malignancy and may be aggravated in patients receiving chemotherapy. Blood transfusions, iron supplementation, and erythropoiesis-stimulating agents (ESAs are established treatment options for anaemic patients.

  3. Effect of Erythropoiesis-Stimulating Agent Policy Decisions

    Data.gov (United States)

    U.S. Department of Health & Human Services — Erythropoiesis-stimulating agents (ESAs) are used as a treatment for anemia in myelodysplastic syndromes (MDS) patients. In early 2007, the U.S. Food and Drug...

  4. Erythropoiesis stimulating agents: approaches to modulate activity

    OpenAIRE

    Sinclair AM

    2013-01-01

    Angus M Sinclair Amgen Inc, Thousand Oaks, CA, USA Abstract: Recombinant human erythropoietin (rHuEPO), such as the approved agents epoetin alfa and epoetin beta, has been used successfully for over 20 years to treat anemia in millions of patients. However, due to the relatively short half-life of the molecule (approximately 8 hours), frequent dosing may be required to achieve required hemoglobin levels. Therefore, a need was identified in some anemic patient populations for erythropoiesis st...

  5. Basic analytical methods for identification of erythropoiesis-stimulating agents in doping control

    Science.gov (United States)

    Postnikov, P. V.; Krotov, G. I.; Efimova, Yu A.; Rodchenkov, G. M.

    2016-02-01

    The design of new erythropoiesis-stimulating agents for clinical use necessitates constant development of methods for detecting the abuse of these substances, which are prohibited under the World Anti-Doping Code and are included in the World Anti-Doping Agency (WADA) prohibited list. This review integrates and describes systematically the published data on the key methods currently used by WADA-accredited anti-doping laboratories around the world to detect the abuse of erythropoiesis-stimulating agents, including direct methods (various polyacrylamide gel electrophoresis techniques, enzyme-linked immunosorbent assay, membrane enzyme immunoassay and mass spectrometry) and indirect methods (athlete biological passport). Particular attention is given to promising approaches and investigations that can be used to control prohibited erythropoietins in the near future. The bibliography includes 122 references.

  6. Erythropoiesis-stimulating agents for the management of anemia of chronic kidney disease: past advancements and current innovations.

    Science.gov (United States)

    Dutka, Paula

    2012-01-01

    Over the last century, remarkable advances have been made in the care of patients with end stage renal disease (ESRD), resulting in improved prognosis. However, for decades after the advent of dialysis, anemia-associated symptoms continued to adversely affect patients' daily lives. The identification, isolation, and eventual cloning of erythropoietin and its receptor led to development of erythropoiesis stimulating agents, revolutionizing anemia management. Continued advancements have paved the way for the discovery of novel erythropoiesis stimulating agents with enhanced properties. This article charts the history of anemia management in patients with ESRD, including the discovery of erythropoietin, and briefly reviews the development, mechanism of action, and select attributes of erythropoiesis-stimulating agents. PMID:23469411

  7. Safety and clinical outcome of erythropoiesis-stimulating agents in patients with ST-elevation myocardial infarction : A meta-analysis of individual patient data

    NARCIS (Netherlands)

    Fokkema, Marieke L.; van der Meer, Peter; Rao, Sunil V.; Belonje, Anne M.; Ferrario, Maurizio; Hillege, Hans L.; Katz, Stuart D.; Lipsic, Erik; Ludman, Andrew J.; Ott, Ilka; Prunier, Fabrice; Choi, Dong-Ju; Toba, Ken; van Veldhuisen, Dirk J.; Voors, Adriaan A.

    2014-01-01

    Background Erythropoiesis-stimulating agents (ESAs) have been investigated in small studies in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Erythropoiesis-stimulating agents did not show a clear effect on left ventricular funct

  8. Ferric Citrate Reduces Intravenous Iron and Erythropoiesis-Stimulating Agent Use in ESRD.

    Science.gov (United States)

    Umanath, Kausik; Jalal, Diana I; Greco, Barbara A; Umeukeje, Ebele M; Reisin, Efrain; Manley, John; Zeig, Steven; Negoi, Dana G; Hiremath, Anand N; Blumenthal, Samuel S; Sika, Mohammed; Niecestro, Robert; Koury, Mark J; Ma, Khe-Ni; Greene, Tom; Lewis, Julia B; Dwyer, Jamie P

    2015-10-01

    Ferric citrate (FC) is a phosphate binder with shown efficacy and additional effects on iron stores and use of intravenous (iv) iron and erythropoiesis-stimulating agents (ESAs). We provide detailed analyses of changes in iron/hematologic parameters and iv iron/ESA use at time points throughout the active control period of a phase 3 international randomized clinical trial. In all, 441 subjects were randomized (292 to FC and 149 to sevelamer carbonate and/or calcium acetate [active control (AC)]) and followed for 52 weeks. Subjects on FC had increased ferritin and transferrin saturation (TSAT) levels compared with subjects on AC by week 12 (change in ferritin, 114.1±29.35 ng/ml; Ptreatment with FC as a phosphate binder results in increased iron parameters apparent after 12 weeks and reduces iv iron and ESA use while maintaining hemoglobin over 52 weeks, with a safety profile similar to that of available binders. PMID:25736045

  9. Intersecting Guidelines: Administering Erythropoiesis-Stimulating Agents to Chronic Kidney Disease Patients with Cancer

    Science.gov (United States)

    Bennett, Charles L.; Becker, Pamela S.; Kraut, Eric H.; Samaras, Athena T.; West, Dennis P.

    2009-01-01

    There has been a dramatic sea change in the use of erythropoiesis-stimulating agents (ESAs) for anemic persons with chronic kidney disease (CKD) or cancer patients undergoing chemotherapy. An important area that has not been addressed previously is a CKD patient who also has a malignancy. Clinical guidelines exist that outline recommended treatments for each disease, but the intersection of the two disease processes presents difficult decisions for patients and physicians. Herein, we review the background underlying recent revisions in clinical alerts and guidelines for ESAs, and provide guidance for treating anemia among CKD patients who are receiving no therapy, chemotherapy with curative intent, or chemotherapy with palliative intent. The guiding principle is that comprehensive assessment of risks and benefits in the relevant clinical setting is imperative. PMID:19175532

  10. Detection of erythropoiesis-stimulating agents in human anti-doping control: past, present and future.

    Science.gov (United States)

    Leuenberger, Nicolas; Reichel, Christian; Lasne, Françoise

    2012-07-01

    Stimulation of erythropoiesis is one of the most efficient ways of doping. This type of doping is advantageous for aerobic physical exercise and of particular interest to endurance athletes. Erythropoiesis, which takes place in bone marrow, is under the control of EPO, a hormone secreted primarily by the kidneys when the arterial oxygen tension decreases. In certain pathological disorders, such as chronic renal failure, the production of EPO is insufficient and results in anemia. The pharmaceutical industry has, thus, been very interested in developing drugs that stimulate erythropoiesis. With this aim, various strategies have been, and continue to be, envisaged, giving rise to an expanding range of drugs that are good candidates for doping. Anti-doping control has had to deal with this situation by developing appropriate methods for their detection. This article presents an overview of both the drugs and the corresponding methods of detection, and thus follows a roughly chronological order. PMID:22831473

  11. Differential Modulation of Angiogenesis by Erythropoiesis-Stimulating Agents in a Mouse Model of Ischaemic Retinopathy

    Science.gov (United States)

    McVicar, Carmel M.; Colhoun, Liza M.; Abrahams, Jodie L.; Kitson, Claire L.; Hamilton, Ross; Medina, Reinhold J.; Durga, Dash; Gardiner, Tom A.; Rudd, Pauline M.; Stitt, Alan W.

    2010-01-01

    Background Erythropoiesis stimulating agents (ESAs) are widely used to treat anaemia but concerns exist about their potential to promote pathological angiogenesis in some clinical scenarios. In the current study we have assessed the angiogenic potential of three ESAs; epoetin delta, darbepoetin alfa and epoetin beta using in vitro and in vivo models. Methodology/Principal Findings The epoetins induced angiogenesis in human microvascular endothelial cells at high doses, although darbepoetin alfa was pro-angiogenic at low-doses (1–20 IU/ml). ESA-induced angiogenesis was VEGF-mediated. In a mouse model of ischaemia-induced retinopathy, all ESAs induced generation of reticulocytes but only epoetin beta exacerbated pathological (pre-retinal) neovascularisation in comparison to controls (p<0.05). Only epoetin delta induced a significant revascularisation response which enhanced normality of the vasculature (p<0.05). This was associated with mobilisation of haematopoietic stem cells and their localisation to the retinal vasculature. Darbepoetin alfa also increased the number of active microglia in the ischaemic retina relative to other ESAs (p<0.05). Darbepoetin alfa induced retinal TNFα and VEGF mRNA expression which were up to 4 fold higher than with epoetin delta (p<0.001). Conclusions This study has implications for treatment of patients as there are clear differences in the angiogenic potential of the different ESAs. PMID:20686695

  12. Differential modulation of angiogenesis by erythropoiesis-stimulating agents in a mouse model of ischaemic retinopathy.

    Directory of Open Access Journals (Sweden)

    Carmel M McVicar

    Full Text Available BACKGROUND: Erythropoiesis stimulating agents (ESAs are widely used to treat anaemia but concerns exist about their potential to promote pathological angiogenesis in some clinical scenarios. In the current study we have assessed the angiogenic potential of three ESAs; epoetin delta, darbepoetin alfa and epoetin beta using in vitro and in vivo models. METHODOLOGY/PRINCIPAL FINDINGS: The epoetins induced angiogenesis in human microvascular endothelial cells at high doses, although darbepoetin alfa was pro-angiogenic at low-doses (1-20 IU/ml. ESA-induced angiogenesis was VEGF-mediated. In a mouse model of ischaemia-induced retinopathy, all ESAs induced generation of reticulocytes but only epoetin beta exacerbated pathological (pre-retinal neovascularisation in comparison to controls (p<0.05. Only epoetin delta induced a significant revascularisation response which enhanced normality of the vasculature (p<0.05. This was associated with mobilisation of haematopoietic stem cells and their localisation to the retinal vasculature. Darbepoetin alfa also increased the number of active microglia in the ischaemic retina relative to other ESAs (p<0.05. Darbepoetin alfa induced retinal TNFalpha and VEGF mRNA expression which were up to 4 fold higher than with epoetin delta (p<0.001. CONCLUSIONS: This study has implications for treatment of patients as there are clear differences in the angiogenic potential of the different ESAs.

  13. Costs of managing anemia with erythropoiesis-stimulating agents during hemodialysis: a time and motion study.

    Science.gov (United States)

    Schiller, Brigitte; Doss, Sheila; DE Cock, Erwin; Del Aguila, Michael A; Nissenson, Allen R

    2008-10-01

    Use of erythropoiesis-stimulating agents (ESAs) presents a significant time and cost burden in the management of anemia of chronic kidney disease (CKD). We conducted a prospective, observational, activity-based costing study to estimate the health care personnel time and resulting direct medical costs associated with administering epoetin 3 times weekly to patients with end-stage renal disease on dialysis. The study was conducted at 5 US hemodialysis centers. The personnel time and costs were derived from time and motion observations. Predicted time and cost savings were modeled for switching patients to once-monthly ESA therapy. Patients also completed a survey questionnaire to assess their level of CKD knowledge and information needs. Total per-patient-per-year (PPPY) time expended on anemia management with epoetin averaged 608 minutes (range 512-915 minutes), with an average PPPY cost of $548 (range $342-$651). Use of a once-monthly ESA, compared with epoetin, could decrease average PPPY time expenditure by 79% (127 minutes [range 96-173 minutes]) and reduce PPPY costs by 81% ($104 [range $79-$136]). The patient questionnaire reported insufficient education on CKD. Use of a once-monthly ESA to correct anemia in dialysis patients may provide substantial time, resource, and cost savings compared with current treatment practices. PMID:19090867

  14. A meta-analysis of the relative doses of erythropoiesis-stimulating agents in patients undergoing dialysis

    OpenAIRE

    Bonafont, Xavier; Bock, Andreas; Carter, Dave; Brunkhorst, Reinhard; Carrera, Fernando; Iskedjian, Michael; Molemans, Bart; Dehmel, Bastian; Robbins, Sean

    2009-01-01

    Background. Erythropoiesis-stimulating agents (ESAs) such as epoetin alfa and beta, and darbepoetin alfa have improved the management of anaemia secondary to chronic kidney disease. Numerous studies have reported a dose reduction when patients receiving dialysis were converted from epoetin to darbepoetin alfa using the starting dose conversion of 200:1 as indicated on the prescribing label by the European Medicines Agency. The objective of this meta-analysis was to summarize the existing body...

  15. The Safety of Erythropoiesis-Stimulating Agents for the Treatment of Anemia Resulting from Chronic Kidney Disease.

    Science.gov (United States)

    Robles, Nicolas Roberto

    2016-06-01

    Chronic kidney disease (CKD) anemia treatment was revolutionized in the late 1980s with the introduction of recombinant human erythropoietin. This and related erythropoiesis-stimulating agents (ESAs) greatly benefited patients by decreasing debilitating symptoms, improving their quality of life, and freeing them from dependence on blood transfusions with their associated complications such as infections, sensitization impeding transplantation, and secondary iron overload. However, even in the initial studies, untoward effects were noted in patients receiving ESAs, including worsening hypertension, seizures, and dialysis access clotting. Later, increased mortality, malignancy progression and even stroke were reported in renal patients. This review focuses on the safety issues of ESAs in CKD patients. PMID:26894799

  16. Erythropoiesis-stimulating agents for the treatment of chemotherapy-induced anemia: comparisons from real-world clinical experience

    Directory of Open Access Journals (Sweden)

    Rodriguez Garzotto A

    2014-04-01

    Full Text Available Analia Rodriguez Garzotto,1 Oliver Heine,2 Matthew Turner,3 Francisco Rebollo Laserna,4 Andreas Lorenz5 1Hospital Universitario 12 de Octubre, Ctra Andalucía, Madrid, Spain; 2Zentralklinikum Suhl, Suhl, 3Sandoz International GmbH, Holzkirchen, Germany; 4Sandoz Farmaceutica SA, Madrid, Spain; 5Frauenarztpraxis, Hildburghausen, GermanyBackground: The purpose of this paper is to report real-world data on the relative effectiveness of a biosimilar erythropoiesis-stimulating agent (ESA; Binocrit®, and other available ESAs for the treatment of chemotherapy-induced anemia.Methods: Data were collected retrospectively from single centers in Spain (n=284 and Germany (n=145. Hemoglobin outcomes, transfusion requirements, and serious drug-related adverse events were assessed for each ESA.Results: Hemoglobin outcomes and transfusion requirements were generally similar in the different ESA treatment groups assessed. No serious drug-related adverse events were recorded in any of the treatment groups.Conclusion: These data confirm the real-world effectiveness and safety of a biosimilar ESA (Binocrit® for the treatment of cancer patients with chemotherapy-induced anemia.Keywords: erythropoiesis-stimulating agents, chemotherapy-induced anemia, biosimilar

  17. Correction of anemia in multiple myeloma patients by erythropoiesis-stimulating agents

    Directory of Open Access Journals (Sweden)

    N. A. Romanenko

    2014-07-01

    Full Text Available In this paper analysis of anemia correction efficacy in multiple myeloma patients was shown. Patients (n = 68 treated with epoetin alfa (recombinant erythropoietin (rEPO 150 IU/kg subcutaneously three times per week (no more 20 weeks were included in the study group. Patients who did not receive erythropoiesis-stimulating therapy were included in the control group (n = 31. Patients in both groups received at least 3 courses of chemotherapy and continued to receive anticancer treatment during follow-up. Baseline hemoglobin level was 5.3 g/dl – 10.0 g/dl. The increase in hemoglobin level to normal range (≥ 12.0 g/dl during ≤ 20 weeks was considered as positive therapy response. Positive response rate was higher in patients received epoetin alfa comparing with control group (64.7 % and 25.8 %, respectively; p < 0.05. Transfusion dependence persisted in 6 from 19 study patients who received RBC transfusions along with rEPO therapy (31.6 %, whereas in 5 from 9 control group patients (55.6 %. In epoetin alfa group significant increase in reticulocytes count at 2–3 weeks of therapywas revealed: from 27.3 × 109/l to 64.9 × 109/l (in patients with positive response and from 13.3 × 109/l to 25.1 × 109/l (in patients without response. Changes in the reticulocytes count in the control group were not revealed. Thus in patients with positive response reticulocytes level significantly increased to 3 weeks of therapy compared with negative response patients (37.6 × 109/l versus 11.8 × 109/l, respectively; p < 0,05, it can be used as prognostic factors of rEPO response.

  18. Dynamics of the erythropoiesis stimulating agent resistance index in incident hemodiafiltration and high-flux hemodialysis patients.

    Science.gov (United States)

    Marcelli, Daniele; Bayh, Inga; Merello, José I; Ponce, Pedro; Heaton, Alex; Kircelli, Fatih; Chazot, Charles; Di Benedetto, Attilio; Marelli, Cristina; Ladanyi, Erzsebet; Kroczak, Miroslaw; Stuard, Stefano; Grassmann, Aileen; Scatizzi, Laura; Brand, Katharina; Canaud, Bernard

    2016-07-01

    Hyporesponsiveness to erythropoiesis-stimulating agent therapy in dialysis patients is poorly understood. Some studies report an improvement in the erythropoiesis-stimulating agent resistance index (ERI) with hemodiafiltration (HDF) versus high-flux hemodialysis (HD). We explored ERI dynamics in 38,340 incident HDF and HD patients treated in 22 countries over a 7-year period. Groups were matched by propensity score at baseline (6 months after dialysis initiation). The follow-up period (mean of 1.31 years) was stratified into 1 month intervals with delta analyses performed for key ERI-related parameters. Dialysis modality, time interval, and polycystic kidney disease were included in a linear mixed model with the outcome ERI. Baseline ERI was nonsignificantly higher in HDF versus HD treatment. ERI decreased significantly faster in HDF-treated patients than in HD-treated patients, was decreased in both HD and HDF when patients were treated with intravenous darbepoetin alfa, but only in HDF when treated with intravenous recombinant human erythropoietin (rHuEPO). A clear difference between HD- and HDF-treated patients could only be found for patients with high baseline ERI and assigned to intravenous rHuEPO treatment. A significant advantage in terms of lower ERI for patients treated by HDF was found. Sensitivity analysis limited this advantage for HDF to those patients treated with intravenous rHuEPO (not darbepoetin alfa or subcutaneous rHuEPO) and to patients with a high baseline ERI. Thus, our results allow more accurate planning for future clinical trials addressing anemia management in dialysis patients. PMID:27178833

  19. Hepcidin-25 in chronic hemodialysis patients is related to residual kidney function and not to treatment with erythropoiesis stimulating agents.

    Directory of Open Access Journals (Sweden)

    Neelke C van der Weerd

    Full Text Available Hepcidin-25, the bioactive form of hepcidin, is a key regulator of iron homeostasis as it induces internalization and degradation of ferroportin, a cellular iron exporter on enterocytes, macrophages and hepatocytes. Hepcidin levels are increased in chronic hemodialysis (HD patients, but as of yet, limited information on factors associated with hepcidin-25 in these patients is available. In the current cross-sectional study, potential patient-, laboratory- and treatment-related determinants of serum hepcidin-20 and -25, were assessed in a large cohort of stable, prevalent HD patients. Baseline data from 405 patients (62% male; age 63.7 ± 13.9 [mean SD] enrolled in the CONvective TRAnsport STudy (CONTRAST; NCT00205556 were studied. Predialysis hepcidin concentrations were measured centrally with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Patient-, laboratory- and treatment related characteristics were entered in a backward multivariable linear regression model. Hepcidin-25 levels were independently and positively associated with ferritin (p<0.001, hsCRP (p<0.001 and the presence of diabetes (p = 0.02 and inversely with the estimated glomerular filtration rate (p = 0.01, absolute reticulocyte count (p = 0.02 and soluble transferrin receptor (p<0.001. Men had lower hepcidin-25 levels as compared to women (p = 0.03. Hepcidin-25 was not associated with the maintenance dose of erythropoiesis stimulating agents (ESA or iron therapy. In conclusion, in the currently studied cohort of chronic HD patients, hepcidin-25 was a marker for iron stores and erythropoiesis and was associated with inflammation. Furthermore, hepcidin-25 levels were influenced by residual kidney function. Hepcidin-25 did not reflect ESA or iron dose in chronic stable HD patients on maintenance therapy. These results suggest that hepcidin is involved in the pathophysiological pathway of renal anemia and iron availability in these patients, but

  20. Recent advances and clinical application of erythropoietin and erythropoiesis-stimulating agents.

    Science.gov (United States)

    Tanaka, Tetsuhiro; Nangaku, Masaomi

    2012-05-15

    Erythropoietin (EPO) is an essential glycoprotein that facilitates red blood cell maturation from erythroid progenitors and mediates erythropoiesis. The use of recombinant human EPO (rhEPO) dramatically changed management of anemic patients with chronic kidney disease and improved their quality of life. EPO is mainly produced in the fetal liver and the postnatal kidney, although the molecular determinants for tissue-specific expression are elusive. Meanwhile, recent advances established a role of hypoxia-inducible factors (HIF) in transcriptionally upregulating EPO in hypoxia. Out of three HIF- isoforms, HIF-2 appears to play a central role. Prolyl hydroxylase domain-containing protein (PHD), a key regulator connecting oxygen availability and HIF-α expression, is also involved in hypoxic induction of EPO mRNA and the precise roles of PHD paralogs in erythropoiesis are now beginning to be uncovered. On the other hand, widespread expression of EPO receptors (EPOR) beyond erythroid progenitors led to the discovery of non-hematopoietic, pleiotropic roles of EPO in the brain, the heart and the kidney. The precise signal transduction pathways of pleiotropic EPO remain unclear, but carbamylated EPO, which fails to bind to the canonical EPOR homodimers or transduce the JAK2-STAT5 signaling, conferred organ protection through multimeric receptors composed of EPO-R and the common β subunit (βCR). The clinical benefit of normalization of anemia in pre-dialysis CKD by EPO therapy is controversial and recent large-scale, randomized-controlled trials do not favor normalization of anemia by EPO in improving cardiovascular as well as renal outcomes. The optimal EPO therapy should be determined based on the clinical context of individual patients. PMID:22414872

  1. Utilization Patterns of IV Iron and Erythropoiesis Stimulating Agents in Anemic Chronic Kidney Disease Patients: A Multihospital Study

    Directory of Open Access Journals (Sweden)

    Avani D. Joshi

    2012-01-01

    Full Text Available Intravenous (IV iron and Erythropoiesis Stimulating Agents (ESAs are recommended for anemia management in chronic kidney disease (CKD. This retrospective cohort study analyzed utilization patterns of IV iron and ESA in patients over 18 years of age admitted to University Health System Hospitals with a primary or secondary diagnosis of CKD between January 1, 2006 to December 31, 2008. A clustered binomial logistic regression using the GEE methodology was used to identify predictors of IV iron utilization. Only 8% (n = 6678 of CKD patients on ESA therapy received IV iron supplementation in university hospitals. Those receiving iron used significantly less amounts of ESAs. Patient demographics (age, race, primary payer, patient clinical conditions (admission status, severity of illness, dialysis status, and physician specialty were identified as predictors of IV iron use in CKD patients. Use of IV iron with ESAs was low despite recommendations from consensus guidelines. The low treatment rate of IV iron represents a gap in treatment practices and signals an opportunity for healthcare improvement in CKD anemic patients.

  2. Effects of erythropoiesis-stimulating agents on heart failure patients with anemia: a meta-analysis

    Science.gov (United States)

    Zhang, Pei; Zhang, Yaheng; Yan, Junqiang; Dong, Pingshuan; Wang, Yanyu; Niu, Xiaowei

    2016-01-01

    Introduction Heart failure (HF) is always complicated with anemia and is associated with bad prognosis in this patient population. Several studies have assessed the potential role of erythropoietin-stimulating agent (ESA) in improving cardiac function and reducing the number of hospitalizations in anemic patients with HF. Aim We performed a meta-analysis to assess the potential role of ESA in the treatment of anemic patients with HF. Material and methods A literature and Medline search was performed to identify studies with control groups that examined the efficacy of ESA therapy in patients with HF and anemia. Results A total of 11 studies were included (n = 3044 subjects) in the final analysis. Compared to placebo, ESA therapy was associated with increased hemoglobin levels (1.89 g/dl; 95% CI: 1.64–2.14, p < 0.00001), increased left ventricular ejection fraction (LVEF) to 6.88 (95% CI: 0.49–13.28, p = 0.03), decreased B-type natriuretic protein (–272.20; 95% CI: (–444.52)–(–99.89), p = 0.002), improvement in New York Heart Association functional class to –0.33 mean difference (95% CI: (–0.44)–(–0.23), p < 0.00001), and decreased hospitalization (OR = 0.61, 95% CI: 0.39–0.94, p = 0.02). There was no significant between-group difference in all-cause mortality (OR = 0.78, 95% CI: 0.51–1.21, p = 0.27). Conclusions The treatment of anemia with ESA therapy did not reduce the rate of all-cause mortality among patients with heart failure, but ESA therapy made a potential important contribution to patients’ symptomatic improvement. PMID:27625688

  3. Implications of a Reduction in the Hemoglobin Target in Erythropoiesis-Stimulating Agent-Treated Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Timothy V. Nguyen

    2011-11-01

    Full Text Available Background: Patients treated with erythropoiesis-stimulating agents (ESAs to a hemoglobin (Hb level >12.0 g/dl have increased risk of multiple complications, including death. The optimal Hb target for ESA use has not been established. We hypothesized that reducing the target Hb would prevent levels >12 g/dl and lead to significant cost savings. Methods: Our target Hb range was reduced to 9–11 g/dl from 10–12 g/dl. Thirty-five chronic hemodialysis (HD patients received erythropoietin (EPO and intravenous iron from January to December 2009. Data analysis included: Hb level, EPO dose, transferrin saturation and ferritin levels. EPO was administered via subcutaneous injection weekly or twice weekly. Results: The mean monthly Hb level changed from 11.2 to 10.6 g/dl. The percentages of patients with mean Hb >10.0, 12.0 and 13.0 g/dl were 82 ± 6.5, 10 ± 5.6 and 1.8 ± 1.9%, respectively. Weekly EPO dose decreased from 9,500 to 5,600 units, a 40% reduction per dose per patient and costs. The savings exceeded USD 60,000 per year for 35 patients. More than 80% of patients had transferrin saturation >20% and ferritin >200 ng/ml throughout the entire period. Conclusions: Lowering the target Hb range to 9–11 g/dl in HD patients achieved quality anemia management, avoided values >12.0 g/dl and resulted in cost savings. A minimal reduction in quality of life and no change in cardiovascular morbidity or mortality would be expected. The study has important implications in the new American bundled reimbursement model.

  4. Erythropoiesis-stimulating agents and other methods to enhance oxygen transport.

    Science.gov (United States)

    Elliott, S

    2008-06-01

    Oxygen is essential for life, and the body has developed an exquisite method to collect oxygen in the lungs and transport it to the tissues. Hb contained within red blood cells (RBCs), is the key oxygen-carrying component in blood, and levels of RBCs are tightly controlled according to demand for oxygen. The availability of oxygen plays a critical role in athletic performance, and agents that enhance oxygen delivery to tissues increase aerobic power. Early methods to increase oxygen delivery included training at altitude, and later, transfusion of packed RBCs. A breakthrough in understanding how RBC formation is controlled included the discovery of erythropoietin (Epo) and cloning of the EPO gene. Cloning of the EPO gene was followed by commercial development of recombinant human Epo (rHuEpo). Legitimate use of this and other agents that affect oxygen delivery is important in the treatment of anaemia (low Hb levels) in patients with chronic kidney disease or in cancer patients with chemotherapy-induced anaemia. However, competitive sports was affected by illicit use of rHuEpo to enhance performance. Testing methods for these agents resulted in a cat-and-mouse game, with testing labs attempting to detect the use of a drug or blood product to improve athletic performance (doping) and certain athletes developing methods to use the agents without being detected. This article examines the current methods to enhance aerobic performance and the methods to detect illicit use. PMID:18362898

  5. Patogenetic correction of anemia with erythropoiesis-stimulating agents in lymphoproliferative disorders (literature review

    Directory of Open Access Journals (Sweden)

    N. A. Romanenko

    2014-07-01

    Full Text Available Literature review of anemia pathogenesis in patients with lymphatic system malignancies is presented. Advantages and disadvanta ges of eritropoiesis-stimulating preparations (ESP used for anemia correction are shown. Efficacy of anemia treatment with ESP in various types of lymphoproliferative disorders (LPD is presented. Prognostic factors that predict positive response on ESP in LPD pati ents and reduce treatment cost are identified.

  6. Discovery and basic pharmacology of erythropoiesis-stimulating agents (ESAs), including the hyperglycosylated ESA, darbepoetin alfa: an update of the rationale and clinical impact.

    Science.gov (United States)

    Kiss, Zoltán; Elliott, Steven; Jedynasty, Kinga; Tesar, Vladimír; Szegedi, János

    2010-04-01

    Cloning of the human erythropoietin (EPO) gene and development of the first recombinant human erythropoietin (rHuEPO) drug were truly breakthroughs. This allowed a deeper understanding of the structure and pharmacology of rHuEpo, which in turn inspired the discovery and development of additional erythropoiesis-stimulating agents (ESAs). In vivo specific activity and serum half-life of rHuEPO are influenced by the amount and structure of the attached carbohydrate. Increased numbers of sialic acids on carbohydrate attached to rHuEPO correlated with a relative increase in in-vivo-specific activity and increased serum half-life. The effect of increasing the number of sialic-acid-containing carbohydrates on in-vivo-specific activity was explored. Initial research focused on solving the problem of how the protein backbone could be engineered so a cell would add more carbohydrate to it. Additional work resulted in darbepoetin alfa, a longer-acting molecule with two additional carbohydrate chains. PMID:20127232

  7. Progressive transfusion and growth factor independence with adjuvant sertraline in low risk myelodysplastic syndrome treated with an erythropoiesis stimulating agent and granulocyte-colony stimulating factor

    OpenAIRE

    Kirtan Nautiyal; Rui Li; Sarvari Yellapragada; Perumal Thiagarajan; Martha Mims; Gustavo Rivero

    2014-01-01

    Refractoriness to growth factor therapy is commonly associated with inferior outcome in patients with low-risk myelodysplastic syndrome (LR-MDS) who require treatment for cytopenias. However, the mechanisms leading to refractoriness are unknown. Here we describe a clinically depressed 74-year-old male with refractory cytopenia with multilineage dysplasia (RCMD) and documented growth factor refractory anemia after erythropoeisis stimulating agent (ESA) therapy, who attained transfusion and gro...

  8. Switching patients with non-dialysis chronic kidney disease from oral iron to intravenous ferric carboxymaltose: effects on erythropoiesis-stimulating agent requirements, costs, hemoglobin and iron status.

    Directory of Open Access Journals (Sweden)

    Jorge Eduardo Toblli

    Full Text Available Patients with non-dialysis-dependent chronic kidney disease (ND-CKD often receive an erythropoiesis-stimulating agent (ESA and oral iron treatment. This study evaluated whether a switch from oral iron to intravenous ferric carboxymaltose can reduce ESA requirements and improve iron status and hemoglobin in patients with ND-CKD.This prospective, single arm and single-center study included adult patients with ND-CKD (creatinine clearance ≤40 mL/min, hemoglobin 11-12 g/dL and iron deficiency (ferritin 20%. Outcome measures were ESA dose requirements during the observation period after initial ferric carboxymaltose treatment (primary endpoint; number of hospitalizations and transfusions, renal function before and after ferric carboxymaltose administration, number of adverse reactions (secondary endpoints. Hemoglobin, mean corpuscular volume, ferritin and transferrin saturation were measured monthly from baseline until end of study. Creatinine clearance, proteinuria, C-reactive protein, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase bimonthly from baseline until end of study.Thirty patients were enrolled (age 70.1±11.4 years; mean±SD. Mean ESA consumption was significantly reduced by 83.2±10.9% (from 41,839±3,668 IU/patient to 6,879±4,271 IU/patient; p<0.01. Hemoglobin increased by 0.7±0.3 g/dL, ferritin by 196.0±38.7 μg/L and transferrin saturation by 5.3±2.9% (month 6 vs. baseline; all p<0.01. No ferric carboxymaltose-related adverse events were reported and no patient withdrew or required transfusions during the study.Among patients with ND-CKD and stable normal or borderline hemoglobin, switching from oral iron to intravenous ferric carboxymaltose was associated with significant improvements in hematological and iron parameters and a significant reduction in ESA dose requirements in this single-center pilot study.ClinicalTrials.gov NCT02232906.

  9. Switching Patients with Non-Dialysis Chronic Kidney Disease from Oral Iron to Intravenous Ferric Carboxymaltose: Effects on Erythropoiesis-Stimulating Agent Requirements, Costs, Hemoglobin and Iron Status

    Science.gov (United States)

    Toblli, Jorge Eduardo; Di Gennaro, Federico

    2015-01-01

    Background Patients with non-dialysis-dependent chronic kidney disease (ND-CKD) often receive an erythropoiesis-stimulating agent (ESA) and oral iron treatment. This study evaluated whether a switch from oral iron to intravenous ferric carboxymaltose can reduce ESA requirements and improve iron status and hemoglobin in patients with ND-CKD. Methods This prospective, single arm and single-center study included adult patients with ND-CKD (creatinine clearance ≤40 mL/min), hemoglobin 11–12 g/dL and iron deficiency (ferritin 20%). Outcome measures were ESA dose requirements during the observation period after initial ferric carboxymaltose treatment (primary endpoint); number of hospitalizations and transfusions, renal function before and after ferric carboxymaltose administration, number of adverse reactions (secondary endpoints). Hemoglobin, mean corpuscular volume, ferritin and transferrin saturation were measured monthly from baseline until end of study. Creatinine clearance, proteinuria, C-reactive protein, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase bimonthly from baseline until end of study. Results Thirty patients were enrolled (age 70.1±11.4 years; mean±SD). Mean ESA consumption was significantly reduced by 83.2±10.9% (from 41,839±3,668 IU/patient to 6,879±4,271 IU/patient; p<0.01). Hemoglobin increased by 0.7±0.3 g/dL, ferritin by 196.0±38.7 μg/L and transferrin saturation by 5.3±2.9% (month 6 vs. baseline; all p<0.01). No ferric carboxymaltose-related adverse events were reported and no patient withdrew or required transfusions during the study. Conclusion Among patients with ND-CKD and stable normal or borderline hemoglobin, switching from oral iron to intravenous ferric carboxymaltose was associated with significant improvements in hematological and iron parameters and a significant reduction in ESA dose requirements in this single-center pilot study. Trial Registration ClinicalTrials.gov NCT02232906 PMID

  10. Progressive transfusion and growth factor independence with adjuvant sertraline in low risk myelodysplastic syndrome treated with an erythropoiesis stimulating agent and granulocyte-colony stimulating factor

    Directory of Open Access Journals (Sweden)

    Kirtan Nautiyal

    2015-01-01

    Full Text Available Refractoriness to growth factor therapy is commonly associated with inferior outcome in patients with low-risk myelodysplastic syndrome (LR-MDS who require treatment for cytopenias. However, the mechanisms leading to refractoriness are unknown. Here we describe a clinically depressed 74-year-old male with refractory cytopenia with multilineage dysplasia (RCMD and documented growth factor refractory anemia after erythropoeisis stimulating agent (ESA therapy, who attained transfusion and growth factor independence after the addition of sertraline to his medication regimen. Our case demonstrates hematological improvement-erythroid (HI-E in growth factor refractory, low risk MDS and highlights a potential mechanistic link between common inflammatory diseases and LR-MDS.

  11. Comparative Effectiveness of Biosimilar, Reference Product and Other Erythropoiesis-Stimulating Agents (ESAs Still Covered by Patent in Chronic Kidney Disease and Cancer Patients: An Italian Population-Based Study.

    Directory of Open Access Journals (Sweden)

    Ylenia Ingrasciotta

    Full Text Available Since 2007 biosimilars of erythropoiesis-stimulating agents (ESAs are available on the Italian market. Very limited post-marketing data exist on the comparative effectiveness of biosimilar and originator ESAs.This population-based study was aimed to compare the effects of biosimilars, reference product and other ESAs still covered by patent on hemoglobinemia in chronic kidney disease (CKD and cancer patients in a Local Health Unit (LHU from Northern Italy.A retrospective cohort study was conducted during the years 2009-2014 using data from Treviso LHU administrative database. Incident ESA users (no ESA dispensing within 6 months prior to treatment start, i.e. index date (ID with at least one hemoglobin measurement within one month prior to ID (baseline Hb value and another measurement between 2nd and 3rd month after ID (follow-up Hb value were identified. The strength of the consumption (as total number of defined daily dose (DDD dispensed during the follow-up divided by days of follow-up and the difference between follow-up and baseline Hb values [delta Hb (ΔHb] were evaluated. Based on Hb changes, ESA users were classified as non-responders (ΔHb≤0 g/dl, responders (02 g/dl. A multivariate ordinal logistic regression model to identify predictors for responsiveness to treatment was performed. All analyses were stratified by indication for use and type of dispensed ESA at ID.Overall, 1,003 incident ESA users (reference product: 252, 25.1%; other ESAs covered by patent: 303, 30.2%; biosimilars: 448, 44.7% with CKD or cancer were eligible for the study. No statistically significant difference in the amount of dose dispensed during the follow-up among biosimilars, reference product and other ESAs covered by patent was found in both CKD and cancer. After three months from treatment start, all ESAs increased Hb values on average by 2g/dl. No differences in ΔHb as well as in frequency of non-responders, responders and highly responders among

  12. Comparative Effectiveness of Biosimilar, Reference Product and Other Erythropoiesis-Stimulating Agents (ESAs) Still Covered by Patent in Chronic Kidney Disease and Cancer Patients: An Italian Population-Based Study

    Science.gov (United States)

    2016-01-01

    Background Since 2007 biosimilars of erythropoiesis-stimulating agents (ESAs) are available on the Italian market. Very limited post-marketing data exist on the comparative effectiveness of biosimilar and originator ESAs. Aim This population-based study was aimed to compare the effects of biosimilars, reference product and other ESAs still covered by patent on hemoglobinemia in chronic kidney disease (CKD) and cancer patients in a Local Health Unit (LHU) from Northern Italy. Methods A retrospective cohort study was conducted during the years 2009–2014 using data from Treviso LHU administrative database. Incident ESA users (no ESA dispensing within 6 months prior to treatment start, i.e. index date (ID)) with at least one hemoglobin measurement within one month prior to ID (baseline Hb value) and another measurement between 2nd and 3rd month after ID (follow-up Hb value) were identified. The strength of the consumption (as total number of defined daily dose (DDD) dispensed during the follow-up divided by days of follow-up) and the difference between follow-up and baseline Hb values [delta Hb (ΔHb)] were evaluated. Based on Hb changes, ESA users were classified as non-responders (ΔHb≤0 g/dl), responders (02 g/dl). A multivariate ordinal logistic regression model to identify predictors for responsiveness to treatment was performed. All analyses were stratified by indication for use and type of dispensed ESA at ID. Results Overall, 1,003 incident ESA users (reference product: 252, 25.1%; other ESAs covered by patent: 303, 30.2%; biosimilars: 448, 44.7%) with CKD or cancer were eligible for the study. No statistically significant difference in the amount of dose dispensed during the follow-up among biosimilars, reference product and other ESAs covered by patent was found in both CKD and cancer. After three months from treatment start, all ESAs increased Hb values on average by 2g/dl. No differences in ΔHb as well as in frequency of non-responders, responders and

  13. Insulin-like growth factor I stimulates erythropoiesis in hypophysectomized rats

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, A.; Zapf, J.; Eckardt, K.U.; Clemons, G.; Froesch, E.R.; Bauer, C. (Universitaet Zurich (Switzerland))

    1988-10-01

    Stimulation of erythropoiesis during growth is necessary to ensure proportionality between erythrocyte mass and body mass. However, the way by which erythrocyte formation is adapted to body growth is still unknown. Growth arrest in hypophysectomized rats is accompanied by decreased erythropoiesis. The authors have, therefore, examined whether insulin-like growth factor I (IGF-I), the mediator of growth hormone effects on body growth, is able to restore erythropoiesis in these animals. Subcutaneous infusions of 120 {mu}g of recombinant human IGF-I per day in hypophysectomized rats led to increases in body weight, {sup 59}Fe incorporation into erythrocytes, and the number of reticulocytes that were similar to increases caused by infusions of 28 milliunits of human growth hormone per day. Body weight gain and {sup 59}Fe incorporation were linearly correlated. Like growth hormone, IGF-I also caused a significant rise in serum erythropoietin concentrations. However, the stimulatory effect on erythropoiesis occurred before serum erythropoietin levels had risen. These results demonstrate that IGF-I mediates the stimulatory effect of growth hormone on erythropoiesis in vivo and thus further support the somatomedin concept. They also show that IGF-I can stimulate erythropoiesis in an endocrine manner, and they suggest two possible routes of action: a direct one and an indirect one by means of enhanced erythropoietin production.

  14. Insulin-like growth factor I stimulates erythropoiesis in hypophysectomized rats

    International Nuclear Information System (INIS)

    Stimulation of erythropoiesis during growth is necessary to ensure proportionality between erythrocyte mass and body mass. However, the way by which erythrocyte formation is adapted to body growth is still unknown. Growth arrest in hypophysectomized rats is accompanied by decreased erythropoiesis. The authors have, therefore, examined whether insulin-like growth factor I (IGF-I), the mediator of growth hormone effects on body growth, is able to restore erythropoiesis in these animals. Subcutaneous infusions of 120 μg of recombinant human IGF-I per day in hypophysectomized rats led to increases in body weight, 59Fe incorporation into erythrocytes, and the number of reticulocytes that were similar to increases caused by infusions of 28 milliunits of human growth hormone per day. Body weight gain and 59Fe incorporation were linearly correlated. Like growth hormone, IGF-I also caused a significant rise in serum erythropoietin concentrations. However, the stimulatory effect on erythropoiesis occurred before serum erythropoietin levels had risen. These results demonstrate that IGF-I mediates the stimulatory effect of growth hormone on erythropoiesis in vivo and thus further support the somatomedin concept. They also show that IGF-I can stimulate erythropoiesis in an endocrine manner, and they suggest two possible routes of action: a direct one and an indirect one by means of enhanced erythropoietin production

  15. The effectiveness and cost-effectiveness of erythropoiesis-stimulating agents (epoetin and darbepoetin) for treating cancer treatment-induced anaemia (including review of technology appraisal no. 142): a systematic review and economic model.

    Science.gov (United States)

    Crathorne, Louise; Huxley, Nicola; Haasova, Marcela; Snowsill, Tristan; Jones-Hughes, Tracey; Hoyle, Martin; Briscoe, Simon; Coelho, Helen; Long, Linda; Medina-Lara, Antonieta; Mujica-Mota, Ruben; Napier, Mark; Hyde, Chris

    2016-01-01

    BACKGROUND Anaemia is a common side effect of cancer treatments and can lead to a reduction in quality of life. Erythropoiesis-stimulating agents (ESAs) are licensed for use in conjunction with red blood cell transfusions to improve cancer treatment-induced anaemia (CIA). OBJECTIVE To investigate the effectiveness and cost-effectiveness of ESAs in anaemia associated with cancer treatment (specifically chemotherapy). DATA SOURCES The following databases were searched from 2004 to 2013: The Cochrane Library, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Web of Science, Cumulative Index to Nursing and Allied Health Literature, British Nursing Index, Health Management Information Consortium, Current Controlled Trials and ClinicalTrials.gov. The US Food and Drug Administration and European Medicines Agency websites were also searched. Bibliographies of included papers were scrutinised for further potentially includable studies. REVIEW METHODS The clinical effectiveness review followed principles published by the NHS Centre for Reviews and Dissemination. Randomised controlled trials (RCTs), or systematic reviews of RCTs, of ESAs (epoetin or darbepoetin) for treating people with CIA were eligible for inclusion in the review. Comparators were best supportive care, placebo or other ESAs. Anaemia- and malignancy-related outcomes, health-related quality of life (HRQoL) and adverse events (AEs) were evaluated. When appropriate, data were pooled using meta-analysis. An empirical health economic model was developed comparing ESA treatment with no ESA treatment. The model comprised two components: one evaluating short-term costs and quality-adjusted life-years (QALYs) (while patients are anaemic) and one evaluating long-term QALYs. Costs and benefits were discounted at 3.5% per annum. Probabilistic and univariate deterministic sensitivity analyses were performed. RESULTS Of 1457 titles and abstracts screened, 23 studies assessing ESAs within their licensed

  16. Stimulation and inhibition of erythropoiesis in donors and hematopoietic effect in irradiated recipient

    International Nuclear Information System (INIS)

    Regeneration dynamics in bone marrow and spleen was studied in rats after irradiation of 800 R and transfusion of bone marrow cells from donors treated in different ways. Priority of the microenvironment of the recipient or of the information obtained in cell donors with respect to further hematopoietic cell differentiation was studied in irradiated recipients. Rats irradiated with 800 R were used as recipients in the experiments. The donors of marrow cells were the rats with stimulated or inhibited erythropoiesis. Stimulation of erythropoiesis was induced by bleeding and experimental polycythemia was provoked by packed erythrocytes. According to our results, it can be concluded that the processes of postirradiation hematopoiesis after transplantation of the bone marrow cells depend on the number and proliferative state of both donors and recipient stem cells, and microenvironment, not excluding the information introduced with the donor cell transplant. (orig.)

  17. Protective roles of erythropoiesis-stimulating proteins in chronic heart failure with anemia

    OpenAIRE

    Zhou, Shuqin; Zhuang, Yugang; Zhao, Wei; Jiang, Bojie; Pan, Hui; Zhang, Xiangyu; Peng, Hu; CHEN, YANQING

    2014-01-01

    Anemia is a common comorbidity in patients with chronic heart failure (CHF) and is frequently treated with erythropoiesis-stimulating proteins (ESPs). Previous studies, however, have been relatively short in duration and have not provided conclusive data on the safety or clinical efficacy of ESP treatment. The aim of this study was to explore the safety and therapeutic effects of ESPs in patients with anemia and CHF. A systematic literature search in EMBASE and MEDLINE from their inception to...

  18. A dimeric peptide with erythropoiesis-stimulating activity uniquely affects erythropoietin receptor ligation and cell surface expression.

    Science.gov (United States)

    Verma, Rakesh; Green, Jennifer M; Schatz, Peter J; Wojchowski, Don M

    2016-08-01

    Erythropoiesis-stimulating agents (ESAs) that exert long-acting antianemia effects have been developed recently, but their mechanisms are poorly understood. Analyses reveal unique erythropoietin receptor (EPOR)-binding properties for one such ESA, the synthetic EPOR agonist peginesatide. Compared with recombinant human EPO and darbepoietin, peginesatide exhibited a slow on rate, but sustained EPOR residency and resistant displacement. In EPO-dependent human erythroid progenitor UT7epo cells, culture in peginesatide unexpectedly upmodulated endogenous cell surface EPOR levels with parallel increases in full-length EPOR-68K levels. These unique properties are suggested to contribute to the durable activity of this (and perhaps additional) dimeric peptide hematopoietic growth factor receptor agonist. PMID:27174804

  19. Erythropoietic Agents and the Elderly

    OpenAIRE

    Agarwal, Neeraj; Prchal, Josef T.

    2008-01-01

    Erythropoietin is a peptide hormone that stimulates erythropoiesis. There are several agents in clinical use and in development, which either act as ligands for the cell surface receptors of erythropoietin or promote erythropoietin production that stimulates erythropoiesis. These are known as erythropoietic agents. The agents already in use include epoetin alfa, epoetin beta, and darbepoetin alfa. Newer agents stimulating erythropoiesis (such as continuous erythropoietin receptor activator (C...

  20. Drug Safety Communication: Erythropoiesis-Stimulating Agents (ESAs)

    Science.gov (United States)

    ... Health and Human Services FDA U.S. Food and Drug Administration Protecting and Promoting Your Health A to ... it was archived. Search Archive Submit archive search Drugs Home Drugs Drug Safety and Availability Postmarket Drug ...

  1. Networking erythropoiesis.

    Science.gov (United States)

    Kerenyi, Marc A; Orkin, Stuart H

    2010-11-22

    A relatively small cadre of lineage-restricted transcription factors largely orchestrates erythropoiesis, but how these nuclear factors interact to regulate this complex biology is still largely unknown. However, recent technological advances, such as chromatin immunoprecipitation (ChIP) paired with massively parallel sequencing (ChIP-seq), gene expression profiling, and comprehensive bioinformatic analyses, offer new insights into the intricacies of red cell molecular circuits. PMID:21098097

  2. Quantitative analysis of dietary iron utilization for erythropoiesis in response to body iron status.

    Science.gov (United States)

    Matsuo-Tezuka, Yukari; Noguchi-Sasaki, Mariko; Kurasawa, Mitsue; Yorozu, Keigo; Shimonaka, Yasushi

    2016-06-01

    Erythropoiesis requires large amounts of iron for hemoglobin synthesis. There are two sources of iron for erythropoiesis, dietary and stored iron; however, their relative contributions to erythropoiesis remain unknown. In this study, we used the stable iron isotope (57)Fe to quantify synthesis of hemoglobin derived from dietary iron. Using this method, we investigated the activities of dietary iron absorption and the utilization of dietary iron for erythropoiesis in responses to stimulated erythropoiesis and to interventions to alter body iron status. Under iron-loaded conditions, the activity of dietary iron absorption was clearly lowered in response to up-regulation of hepcidin, although the estimated activity of iron release from stored iron was not compared with that under control conditions. This result was supported by the observation that two duodenal iron transporters, divalent metal transporter 1 (DMT1) and ferroportin, were downregulated by iron loading, although the levels of expression of ferroportin in iron storage tissues were not changed by iron loading under erythropoietic stimulation by epoetin-β pegol (C.E.R.A., a long-acting erythropoiesis-stimulating agent). These results indicate that the dietary iron absorption system is more sensitive to body iron status than are reticuloendothelial iron- release mechanisms. Our data indicated that there could be a regulatory mechanism favoring use of stored iron over dietary iron under iron-loaded conditions. PMID:26911670

  3. MUTUAL INHIBITION OF MURINE ERYTHROPOIESIS AND GRANULOPOIESIS DURING COMBINED ERYTHROPOIETIN, GRANULOCYTE-COLONY-STIMULATING FACTOR, AND STEM-CELL FACTOR ADMINISTRATION - IN-VIVO INTERACTIONS AND DOSE-RESPONSE SURFACES

    NARCIS (Netherlands)

    DEHAAN, G; ENGEL, C; DONTJE, B; NIJHOF, W; LOEFFLER, M

    1994-01-01

    We investigated the in vivo effects of erythropoietin (EPO) on granulopoiesis and, conversely, the effect of granulocyte colony-stimulating factor (G-CSF) treatment on erythropoiesis. Recombinant human EPO at four different doses in combination with recombinant human G-CSF also at four different dos

  4. Improvement in Erythropoieis-stimulating Agent-induced Pure Red-cell Aplasia by Introduction of Darbepoetin-α When the Anti-erythropoietin Antibody Titer Declines Spontaneously

    OpenAIRE

    Lee, Hajeong; Yang, Jaeseok; Kim, Hyosang; Kwon, Ju Won; Oh, Kook-Hwan; Joo, Kwon Wook; Kim, Yon Su; Ahn, Curie; Han, Jin Suk; Kim, Suhnggwon

    2010-01-01

    Anti-erythropoietin antibodies usually cross-react with all kinds of recombinant erythropoietins; therefore, erythropoiesis-stimulating agent (ESA)-induced pure red-cell aplasia (PRCA) is not rescued by different ESAs. Here, we present a case of ESA-induced PRCA in a 36-yr-old woman with chronic kidney disease, whose anemic condition improved following reintroduction of darbepoetin-α. The patient developed progressive, severe anemia after the use of erythropoietin-α. As the anemia did not imp...

  5. Effects of radiation on erythropoiesis

    International Nuclear Information System (INIS)

    Since the pioneer work of Heineke (1903; 1905) many workers have studied the effect of radiation on haemopoiesis. Their work has been reviewed by Bloom (1948), by Jacobson (1954) and more recently by Bond et al. (1965). The subject continues to stimulate much interest but is now more concerned with the effects of radiation on the multipotential stem cell pool than on radiation damage to the erythropoietic cells themselves. Death from haemopoietic failure following an LD50/30 dose of radiation is probably not attributable to failure of erythropoiesis; while damage to the erythropoietic system certainly plays a part in the syndrome, it is not a major factor contributing to the death of the animal. Although the severity and time course of the response vary with the species studied, the general effects of radiation on erythropoiesis are similar in all mammalian bone marrow studied to date. Likewise, though the severity of the reaction varies somewhat with the energy of the radiation and has been used to compare the relative biological effectiveness of different types of radiation (Sinclair et al., 1962; Sztanyik, 1967), the response is different only in degree and not in its fundamental pattern. The initial syndrome of depression and recovery will therefore be described largely by reference to work performed on the response of the rat to single acute exposures of either whole-body or partial-body irradiation with conventional X-rays

  6. [Antipsychotic agents and stimulants: a judicious combination?].

    Science.gov (United States)

    de Jong, M H; Eussen, M L J M; van Gool, A R

    2010-01-01

    A 31-year-old male, diagnosed with schizophrenia and receiving maintenance treatment with olanzapine, was prescribed methylphenidate for comorbid attention deficit hyperactivity disorder (adhd). The adhd symptoms diminished and there were hardly any side-effects. No increase in psychotic symptoms occurred. The patient used far fewer amphetamines and benzodiazepines. In theory, stimulants and antipsychotics produce opposite effects. Relevant literature on the subject is discussed. PMID:20054798

  7. Erythropoiesis-stimulating agents for the treatment of chemotherapy-induced anemia: comparisons from real-world clinical experience [Corrigendum

    Directory of Open Access Journals (Sweden)

    Rodriguez Garzotto A

    2014-07-01

    Full Text Available Rodriguez Garzotto A, Heine O, Turner M, et al. J Blood Med. 2014;5:43–48.The author list should have been:Analia Rodriguez Garzotto1Susana Cortijo Casacajares1Cristina Pernaut1Gustavo Javier Ruiz Ares1Irene Otero Blas1Oliver Heine2Matthew Turner3Francisco Rebollo Laserna4Hernan Cortes Funes1Andreas Lorenz51Hospital Universitario 12 de Octubre, Ctra Andalucía, Madrid, Spain; 2Zentralklinikum Suhl, Suhl, 3Sandoz International GmbH, Holzkirchen, Germany; 4Sandoz Farmaceutica SA, Madrid, Spain; 5Frauenarztpraxis, Hildburghausen, GermanyRead the original article

  8. Erythropoiesis-stimulating agents for the treatment of chemotherapy-induced anemia: comparisons from real-world clinical experience [Corrigendum

    OpenAIRE

    Rodriguez Garzotto A; Cortijo Casacajares S; Pernaut C; Ruiz Ares GJ; Otero Blas I; Heine O; Turner M.; Rebollo Laserna F; Cortes Funes H; Lorenz A

    2014-01-01

    Rodriguez Garzotto A, Heine O, Turner M, et al. J Blood Med. 2014;5:43–48.The author list should have been:Analia Rodriguez Garzotto1Susana Cortijo Casacajares1Cristina Pernaut1Gustavo Javier Ruiz Ares1Irene Otero Blas1Oliver Heine2Matthew Turner3Francisco Rebollo Laserna4Hernan Cortes Funes1Andreas Lorenz51Hospital Universitario 12 de Octubre, Ctra Andalucía, Madrid, Spain; 2Zentralklinikum Suhl, Suhl, 3Sandoz International GmbH, Holzkirchen, Germany; 4Sandoz Farmaceutica SA, Ma...

  9. Macrophages support splenic erythropoiesis in 4T1 tumor-bearing mice.

    Directory of Open Access Journals (Sweden)

    Min Liu

    Full Text Available Anemia is a common complication of cancer; a role of spleen in tumor-stress erythropoiesis has been suggested. However, the molecular mechanisms involved in the splenic erythropoiesis following tumor maintenance remain poorly understood. Here we show that tumor development blocks medullar erythropoiesis by granulocyte colony-stimulating factor (G-CSF and then causes anemia in murine 4T1 breast tumor-bearing mice. Meanwhile, tumor-stress promotes splenic erythropoiesis. Splenectomy worsened tumor-induced anemia, and reduced tumor volume and tumor weight, indicating the essential role of spleen in tumor-stress erythropoiesis and tumor growth. Tumor progression of these mice led to increased amounts of bone morphogenetic protein 4 (BMP4 in spleen. The in vivo role of macrophages in splenic erythropoiesis under tumor-stress conditions was investigated. Macrophage depletion by injecting liposomal clodronate decreased the expression of BMP4, inhibited splenic erythropoiesis, aggravated the tumor-induced anemia and suppressed tumor growth. Our results provide insight that macrophages and BMP4 are positive regulators of splenic erythropoiesis in tumor pathological situations. These findings reveal that during the tumor-stress period, the microenvironment of the spleen is undergoing changes, which contributes to adopt a stress erythropoietic fate and supports the expansion and differentiation of stress erythroid progenitors, thereby replenishing red blood cells and promoting tumor growth.

  10. Quantitation of erythropoiesis in myelomatosis

    DEFF Research Database (Denmark)

    Birgens, H S; Hansen, O P; Henriksen, Jens Henrik Sahl; Wantzin, P

    1979-01-01

    Quantitation of the erythropoiesis with radio-iron (59Fe) was applied to 9 patients with untreated myelomatosis. The method included blocking of the 59Fe reutilization by injection of non-radioactive iron. There was no uniform pattern in the Fe-kinetics values. The Plasma Iron Turnover (PIT) and...

  11. A Review of Natural Stimulant and Non-stimulant Thermogenic Agents.

    Science.gov (United States)

    Stohs, Sidney J; Badmaev, Vladimir

    2016-05-01

    Obesity and overweight are major health issues. Exercise and calorie intake control are recognized as the primary mechanisms for addressing excess body weight. Naturally occurring thermogenic plant constituents offer adjunct means for assisting in weight management. The controlling mechanisms for thermogenesis offer many intervention points. Thermogenic agents can act through stimulation of the central nervous system with associated adverse cardiovascular effects and through metabolic mechanisms that are non-stimulatory or a combination thereof. Examples of stimulatory thermogenic agents that will be discussed include ephedrine and caffeine. Examples of non-stimulatory thermogenic agents include p-synephrine (bitter orange extract), capsaicin, forskolin (Coleus root extract), and chlorogenic acid (green coffee bean extract). Green tea is an example of a thermogenic with the potential to produce mild but clinically insignificant undesirable stimulatory effects. The use of the aforementioned thermogenic agents in combination with other extracts such as those derived from Salacia reticulata, Sesamum indicum, Lagerstroemia speciosa, Cissus quadrangularis, and Moringa olifera, as well as the use of the carotenoids as lutein and fucoxanthin, and flavonoids as naringin and hesperidin can further facilitate energy metabolism and weight management as well as sports performance without adverse side effects. © 2016 The Authors Phytotherapy Research published by John Wiley & Sons Ltd. PMID:26856274

  12. Androgens and erythropoiesis: past and present.

    Science.gov (United States)

    Shahani, S; Braga-Basaria, M; Maggio, M; Basaria, S

    2009-09-01

    Association between androgens and erythropoiesis has been known for more than seven decades. Androgens stimulate hematopoietic system by various mechanisms. These include stimulation of erythropoietin release, increasing bone marrow activity and iron incorporation into the red cells. Before the discovery of recombinant erythropoietin (rhEpo), androgens were used in the treatment of anemia associated with renal disease, bone marrow suppression, and hypopituitarism. Anabolism is an additional advantage of androgen therapy. Furthermore, in light of recent reports regarding adverse effects of rhEpo, the role of androgen therapy in various types of anemias should be readdressed. Polycythemia remains a known side effect of androgen therapy. In this review, we will briefly discuss the initial animal and human studies which demonstrated the role of androgens in the treatment of anemia, their mechanism of action, a detailed account of the efficacy of androgens in the treatment of various anemias, the erythropoietic side effects of androgens and finally, the relationship between hematocrit levels and cardiovascular disease. PMID:19494706

  13. Advances in understanding erythropoiesis: evolving perspectives.

    Science.gov (United States)

    Nandakumar, Satish K; Ulirsch, Jacob C; Sankaran, Vijay G

    2016-04-01

    Red blood cells (RBCs) are generated from haematopoietic stem and progenitor cells (HSPCs) through the step-wise process of differentiation known as erythropoiesis. In this review, we discuss our current understanding of erythropoiesis and highlight recent advances in this field. During embryonic development, erythropoiesis occurs in three distinct waves comprising first, the yolk sac-derived primitive RBCs, followed sequentially by the erythro-myeloid progenitor (EMP) and HSPC-derived definitive RBCs. Recent work has highlighted the complexity and variability that may exist in the hierarchical arrangement of progenitors responsible for erythropoiesis. Using recently defined cell surface markers, it is now possible to enrich for erythroid progenitors and precursors to a much greater extent than has been possible before. While a great deal of knowledge has been gained on erythropoiesis from model organisms, our understanding of this process is currently being refined through human genetic studies. Genes mutated in erythroid disorders can now be identified more rapidly by the use of next-generation sequencing techniques. Genome-wide association studies on erythroid traits in healthy populations have also revealed new modulators of erythropoiesis. All of these recent developments have significant promise not only for increasing our understanding of erythropoiesis, but also for improving our ability to intervene when RBC production is perturbed in disease. PMID:26846448

  14. Heme Oxygenase-1 Deletion Affects Stress Erythropoiesis

    OpenAIRE

    Cao, Yu-An; Kusy, Sophie; Luong, Richard; Wong, Ronald J.; Stevenson, David K.; Contag, Christopher H.

    2011-01-01

    Background Homeostatic erythropoiesis leads to the formation of mature red blood cells under non-stress conditions, and the production of new erythrocytes occurs as the need arises. In response to environmental stimuli, such as bone marrow transplantation, myelosuppression, or anemia, erythroid progenitors proliferate rapidly in a process referred to as stress erythropoiesis. We have previously demonstrated that heme oxygenase-1 (HO-1) deficiency leads to disrupted stress hematopoiesis. Here,...

  15. Erythropoietic agents and the elderly.

    Science.gov (United States)

    Agarwal, Neeraj; Prchal, Josef T

    2008-10-01

    Erythropoietin (Epo) is a peptide hormone that stimulates erythropoiesis. There are several agents in clinical use and in development that either act as ligands for the cell surface receptors of Epo or promote Epo production, which stimulates erythropoiesis. These are known as erythropoietic agents. The agents already in use include epoetin alfa, epoetin beta, and darbepoetin alfa. Newer agents under active investigation include continuous erythropoietin receptor activator (CERA) or proline hydroxylase inhibitors that increase hypoxia-inducible factor-1 (HIF-1), thereby stimulating Epo production and iron availability and supply. Erythropoietic agents have been shown to promote neuronal regeneration and to decrease post-stroke infarct size in mouse models. They have also been reported to shorten survival when used to treat anemia in many cancer patients and to increase thromboembolism. In contrast, rapid decrease of Epo levels as observed in astronauts and high-altitude dwellers upon rapid descent to sea level leads to the decrease of erythroid mass, a phenomenon known as "neocytolysis." The relative decrease in the serum Epo level is known to occur in some subjects with otherwise unexplained anemia of aging. Anemia by itself is a predictor of poor physical function in the elderly and is a significant economic burden on society. One out of every five persons in the United States will be elderly by 2050. Erythropoietic agents, by preventing and treating otherwise unexplained anemias of the elderly and anemia associated with other disease conditions of the elderly, have the potential to improve the functional capacity and to decrease the morbidity and mortality in the elderly, thereby alleviating the overall burden of medical care in society. PMID:18809098

  16. Heme oxygenase-1 deletion affects stress erythropoiesis.

    Directory of Open Access Journals (Sweden)

    Yu-An Cao

    Full Text Available BACKGROUND: Homeostatic erythropoiesis leads to the formation of mature red blood cells under non-stress conditions, and the production of new erythrocytes occurs as the need arises. In response to environmental stimuli, such as bone marrow transplantation, myelosuppression, or anemia, erythroid progenitors proliferate rapidly in a process referred to as stress erythropoiesis. We have previously demonstrated that heme oxygenase-1 (HO-1 deficiency leads to disrupted stress hematopoiesis. Here, we describe the specific effects of HO-1 deficiency on stress erythropoiesis. METHODOLOGY/PRINCIPAL FINDINGS: We used a transplant model to induce stress conditions. In irradiated recipients that received hmox(+/- or hmox(+/+ bone marrow cells, we evaluated (i the erythrocyte parameters in the peripheral blood; (ii the staining intensity of CD71-, Ter119-, and CD49d-specific surface markers during erythroblast differentiation; (iii the patterns of histological iron staining; and (iv the number of Mac-1(+-cells expressing TNF-α. In the spleens of mice that received hmox(+/- cells, we show (i decreases in the proerythroblast, basophilic, and polychromatophilic erythroblast populations; (ii increases in the insoluble iron levels and decreases in the soluble iron levels; (iii increased numbers of Mac-1(+-cells expressing TNF-α; and (iv decreased levels of CD49d expression in the basophilic and polychromatophilic erythroblast populations. CONCLUSIONS/SIGNIFICANCE: As reflected by effects on secreted and cell surface proteins, HO-1 deletion likely affects stress erythropoiesis through the retention of erythroblasts in the erythroblastic islands of the spleen. Thus, HO-1 may serve as a therapeutic target for controlling erythropoiesis, and the dysregulation of HO-1 may be a predisposing condition for hematologic diseases.

  17. Comparative behavioral effects of anticholinergic agents in cats: psychomotor stimulation and aggression.

    Science.gov (United States)

    Beleslin, D B; Stefanović-Denić, K; Samardzić, R

    1986-03-01

    The effect on behavior of eight anticholinergic agents: atropine, scopolamine, trihexyphenidyl, biperiden, homatropine, eucatropine, hexocyclium and propantheline, injected into the cerebral ventricle (ICV) of the cat was investigated and compared. The anticholinergic agents evoked: (1) psychomotor stimulation such as miaowing, loud calling, restlessness, impelling locomotion, jumping, vacant staring, apprehension and loss of interest of the surroundings; (2) aggression, hissing, threat, attack, defense, fighting with paws and flight; (3) autonomic responses including mydriasis, tachypnea, dyspnea, licking, vomiting, salivation, micturition and defection; and (4) motor phenomena comprising scratching, ataxia, rigidity, tremor, weakness with adynamia or myoclonic jerks. Convulsions appeared only after ICV injections of atropine and homatropine. The most characteristic behavioral effect of anticholinergic agents was psychomotor stimulation accompanied by mild aggressive responses. The only exception was propantheline which caused a muscular weakness and adynamia. Atropine and scopolamine alone induced a dose-dependent impelling locomotion as well as fighting behavior. Carbachol and eserine injected intracerebroventricularly reversed the locomotion autonomic and motor phenomena produced by anticholinergic agents administered similarly. It is suggested that anticholinergic agents acting as partial agonists, can produce their behavioral effects through central cholinoceptive sites. PMID:3703893

  18. Ferrokinetic study of splenic erythropoiesis: Relationships among clinical diagnosis, myelofibrosis, splenomegaly, and extramedullary erythropoiesis

    Energy Technology Data Exchange (ETDEWEB)

    Beguin, Y.; Fillet, G.; Bury, J.; Fairon, Y. (Univ. of Liege (Belgium))

    1989-10-01

    Splenic erythropoiesis was demonstrated by surface counting of {sup 59}Fe in 129 of 1,350 ferrokinetic studies performed over a 15 year period. These 129 studies were carried out in 108 patients, including 40 with chronic myelogenous leukemia (CML), 24 with agnogenic myeloid metaplasia (AMM), 18 with polycythemia vera (PV), six with a myelodysplastic syndrome, five with acute leukemia, three with prostate or breast carcinoma, two each with aplastic anemia or Hodgkin's disease, and one each with idiopathic thrombocythemia, multiple myeloma, chronic renal failure, or treated hypopituitarism. Splenomegaly was present in 83% of the studies and hepatomegaly in 72%. Grade II-III myelofibrosis was demonstrated in 62% of the cases. Hepatic erythropoiesis was present in 77% of the studies (only 38% in PV), and marrow erythropoiesis was undetectable in 33%. Total erythropoiesis was about twice normal (range 0.2 to 8 times normal) but was ineffective to varying degrees in 86% of the studies. Relationships between organomegaly, myelofibrosis, and extramedullary erythropoiesis, as well as differences among clinical disorders, are discussed. Differences observed between CML in chronic or blastic phase suggested that the erythroid cell line was involved in the proliferative process. It is concluded that splenic erythropoiesis (1) is encountered in a variety of clinical conditions; (2) is not necessarily associated with splenomegaly or myelofibrosis, even in the myeloproliferative disorders; (3) is part of a predominantly extramedullary (in the liver as well as in the spleen), expanded, and largely inefficient total erythropoiesis; and (4) can be evaluated in a semiquantitative manner by surface counting.

  19. Iron Metabolism: Interactions with Normal and Disordered Erythropoiesis

    OpenAIRE

    Ganz, Tomas; Nemeth, Elizabeta

    2012-01-01

    Hemoglobinopathies and other disorders of erythroid cells are often associated with abnormal iron homeostasis. We review the molecular physiology of intracellular and systemic iron regulation, and the interactions between erythropoiesis and iron homeostasis. Finally, we discuss iron disorders that affect erythropoiesis as well as erythroid disorders that cause iron dysregulation.

  20. Iron supply for erythropoiesis in the rabbit.

    OpenAIRE

    Celada, A; Stray, S; Sivarajan, M; Finch, C

    1984-01-01

    Marrow radioiron uptake and marrow blood flow were measured in order to evaluate iron supply for erythropoiesis. Normal, phenylhydrazine-treated and bled animals were studied. The plasma iron turnover of seven normal rabbits was 1.49 +/- 0.22 mg/dl whole blood per d, of 11 rabbits treated 4 d before with phenylhydrazine was 5.16 +/- 1.81, and of four bled animals the plasma iron turnover was 3.75 +/- 1.61. The cardiac output and the percentage of blood flow to the marrow was increased in phen...

  1. Macrophage migration inhibitory factor is an endogenous regulator of stress-induced extramedullary erythropoiesis.

    Science.gov (United States)

    Vignjević Petrinović, Sanja; Budeč, Mirela; Marković, Dragana; Gotić, Mirjana; Mitrović Ajtić, Olivera; Mojsilović, Slavko; Stošić-Grujičić, Stanislava; Ivanov, Milan; Jovčić, Gordana; Čokić, Vladan

    2016-09-01

    Macrophage migration inhibitory factor is a well-known proinflammatory cytokine that is released during systemic stress response. Although MIF can affect erythrocyte production, the role of this cytokine in stress-induced erythropoiesis is completely unknown. To extend our previous findings showing that chronic psychological stress stimulates extramedullary erythropoiesis, here we examined whether MIF is involved in the control of stress-induced erythropoietic response. Adult male C57BL/6 wild-type (WT) and MIF-KO (knock-out) mice were subjected to 2-h daily restraint stress for either 7 or 14 consecutive days. The number of erythroid progenitors and CD71/Ter119 profile of erythroid precursors were analyzed in the bone marrow and spleen. Additionally, MIF protein expression was assessed in WT mice. Our results demonstrated that chronic restraint stress enhanced the number of both erythroid progenitors and precursors in the spleen. Stress-induced increase in the number of splenic late erythroid progenitors as well as in the percentage of CD71(+)Ter119(+)-double-positive precursors was significantly more pronounced in MIF-KO mice compared to WT animals. Furthermore, repeatedly stressed WT animals demonstrated an augmented MIF expression in the spleen. Unlike the spleen, the bone marrow of chronically stressed WT mice exhibited less prominent changes in erythropoietic stress response and no significant alteration in MIF expression. In addition, MIF deficiency did not influence the bone marrow erythropoiesis in stressed animals. These findings suggest that MIF regulates extramedullary erythropoiesis by inhibiting an overexpansion of splenic immature erythroid cells during chronic stress and indicate a novel role for this cytokine under chronic stress conditions. PMID:27129368

  2. Erythroblastic Islands: Specialized Mircoenvironmental Niches forErythropoiesis

    Energy Technology Data Exchange (ETDEWEB)

    Chasis, Joel Anne

    2006-01-06

    This review focuses on current understanding of molecular mechanisms operating within erythroblastic islands including cell-cell adhesion, regulatory feedback, and central macrophage function. RECENT FINDINGS: Erythroblasts express a variety of adhesion molecules and recently two interactions have been identified that appear to be critical for island integrity. Erythroblast macrophage protein, expressed on erythroblasts and macrophages, mediates cell-cell attachments via homophilic binding. Erythroblast intercellular adhesion molecule-4 links erythroblasts to macrophages through interaction with macrophage alphav integrin. In intercellular adhesion molecule-4 knockout mice, erythroblastic islands are markedly reduced, whereas the erythroblast macrophage protein null phenotype is severely anemic and embryonic lethal. Retinoblastoma tumor suppressor (Rb) protein stimulates macrophage differentiation by counteracting inhibition of Id2 on PU.1, a transcription factor that is a crucial regulator of macrophage differentiation. Rb-deficient macrophages do not bind Rb null erythroblasts and the Rb null phenotype is anemic and embryonic lethal. Lastly, extruded nuclei rapidly expose phosphatidylserine on their surface, providing a recognition signal similar to apoptotic cells. SUMMARY: Although understanding of molecular mechanisms operating within islands is at an early stage, tantalizing evidence suggests that erythroblastic islands are specialized niches where intercellular interactions in concert with cytokines play critical roles in regulating erythropoiesis.

  3. Stimulating erythropoiesis in inflammatory bowel disease associated anemia

    Institute of Scientific and Technical Information of China (English)

    Georgia Tsiolakidou; Ioannis E Koutroubakis

    2007-01-01

    Anemia is a frequent complication in patients with inflammatory bowel disease (IBD), and is associated with decreased quality of life and increased rate of hospitalization. The primary therapeutic targets of IBDassociated anemia are iron deficiency and anemia of chronic disease. An important prognostic parameter of the success or failure of therapy is the outcome of the underlying disease. Iron deficiency should be appropriately managed with iron supplementation.However, the use of oral iron therapy is limited by several problems, the most important being gastrointestinal side effects leading occasionally to disease relapse and poor iron absorption. Intravenous iron preparations are more reliable, with iron sucrose demonstrating the best efficacy and tolerability. Treatment with erythropoietin or darbepoetin has been proven to be effective in patients with anemia, who fail to respond to intravenous iron. Patients with ongoing inflammation have anemia of chronic disease and may require combination therapy comprising of intravenous iron sucrose and erythropoietin. After initiating treatment, careful monitoring of hemoglobin levels and iron parameters is needed in order to avoid recurrence of anemia. In conclusion, anemia in the setting of IBD should be aggressively diagnosed, investigated, and treated. Future studies should define the optimal dose and schedule of intravenous iron supplementation and appropriate erythropoietin therapy in these patients.

  4. Iron Loading and Overloading due to Ineffective Erythropoiesis

    Directory of Open Access Journals (Sweden)

    Toshihiko Tanno

    2010-01-01

    Full Text Available Erythropoiesis describes the hematopoietic process of cell proliferation and differentiation that results in the production of mature circulating erythrocytes. Adult humans produce 200 billion erythrocytes daily, and approximately 1 billion iron molecules are incorporated into the hemoglobin contained within each erythrocyte. Thus, iron usage for the hemoglobin production is a primary regulator of plasma iron supply and demand. In many anemias, additional sources of iron from diet and tissue stores are needed to meet the erythroid demand. Among a subset of anemias that arise from ineffective erythropoiesis, iron absorption and accumulation in the tissues increases to levels that are in excess of erythropoiesis demand even in the absence of transfusion. The mechanisms responsible for iron overloading due to ineffective erythropoiesis are not fully understood. Based upon data that is currently available, it is proposed in this review that loading and overloading of iron can be regulated by distinct or combined mechanisms associated with erythropoiesis. The concept of erythroid regulation of iron is broadened to include both physiological and pathological hepcidin suppression in cases of ineffective erythropoiesis.

  5. Study of erythropoiesis with 59Fe and erythrocyte survival with 51Cr in aplastic anemia

    International Nuclear Information System (INIS)

    A study of erythropoiesis with 59Fe and erythrocyte survival with 51Cr was carried out in 25 patients with aplastic anemia and in a control group of 23 healthy persons. Bone marrow aplasia was uniform in all patients but differences in erythropoiesis were established. According to the state of erythropoiesis, the patients were divided into two groups: 1) patients with severe damage of erythropoiesis and 2) patients with preserved erythropoiesis. Erythrocyte survival in both groups was shortened. The data obtained correlate with the anemic syndrome and help to explain its pathogenesis. It is suggested that the investigation of erythropoiesis with 59Fe and 51Cr is of prognostic value. (author)

  6. Roles of transferrin receptors in erythropoiesis.

    Science.gov (United States)

    Kawabata, Hiroshi; Sakamoto, Soichiro; Masuda, Taro; Uchiyama, Tatsuki; Ohmori, Katsuyuki; Koeffler, H Phillip; Takaori-Kondo, Akifumi

    2016-07-01

    Erythropoiesis requires large amounts of iron for hemoglobin synthesis, which is mainly provided by macrophages and the intestines in a transferrin (Tf)-bound form. Bone marrow erythroblasts incorporate Tf through endocytosis, which is mediated by transferrin receptor 1 (TFR1). Recently, human TFR1, aside from its role as a Tf receptor, was also found to be a receptor for the H-subunit of ferritin (FTH). In humans, hematopoietic erythroid precursor cells express high levels of TFR1 and specifically take up the FTH homopolymer (H-ferritin). H-ferritin inhibits the formation of burst forming unit-erythroid colonies in vitro. TFR2, which is also a Tf receptor, is predominantly expressed in hepatocytes and erythroid precursor cells. In the liver, TFR2 forms a complex with HFE, a hereditary hemochromatosis-associated protein, and acts as an iron sensor. In mice, hepatocyte-specific knockout of the TFR2 gene has been shown to cause systemic iron-overload with decreased expression of hepcidin, the central regulator of iron homeostasis. In erythroid cells, TFR2 forms a complex with the erythropoietin receptor and facilitates its trafficking to the cell membrane. Moreover, hematopoietic cell-specific knockout of the TFR2 gene causes microcytic erythrocytosis in mice. This review focuses on the molecular evolution and functions of these TFRs and their ligands. PMID:27498743

  7. Cardio-renal-anemia syndromeとErythropoietin Stimulating Agents(ESA)

    OpenAIRE

    成宮, 博理; 山田, 博之; 北川, 功幸; 原山, 拓也; 熱田, 晴彦; 井上, 衛; 出口, 雅子

    2011-01-01

     近年の様々な疫学調査や大規模臨床試験により,慢性腎臓病(CKD)が心血管疾患(CVD)の独立した危険因子であることが明らかになった.さらに,CKD のCVD へのリスクとなる間に介在する要因として,貧血が大きな役割を果たしていることが証明されてきた.このようにCKD,CVD,貧血がお互いに悪影響を及ぼし合い,悪循環を形成するという考えをcardio-renal-anemia syndromeと呼ぶようになった.保存期CKD やうっ血性心不全に対する介入は困難が予想される.一方で,Erythropoietin stimulating agents と呼ばれるrHuEPO などを使用した腎性貧血の治療は,心機能を改善し腎機能増悪を抑制させることが報告されている.ここでは,cardio-renal-anemia syndrome の概念と新しいESA について紹介する....

  8. An evaluation of pretreatment agents for the stimulation of secondary biogenic coalbed natural gas

    Science.gov (United States)

    Huang, Zaixing

    Coalbed methane is considered to be an underexploited source of clean energy and, with the realization of its biogenic nature, it has attracted increasing interest in recent decades. Most of the published studies on biogenic coal bed natural gas (CBNG) have focused either on biostimulation (the addition of nutrients to stimulate the native microbial populations) or bioaugmentation (the addition of both nutrients and non-native microbial consortia of microorganisms). Although these approaches have shown promise, they are predicated on the assumption that the coal seam is nutrient-limited or that the existing microbial communities are not optimized to convert coal to natural gas. The premise of this research is that the organic matter present within the coal matrix is, for the most part, environmentally inert and not readily available to the microorganisms living within the coal seam. The goal of this research has been to focus on treatments that will increase the solubility, and hence the bioavailability, of coal to the indigenous microbial community. Initially, treatment agents representing acids, bases and oxidants were selected to evaluate the potential for the in situ solubilization and depolymerization of subbituminous coal. The bioavailability of the coal-derived constituents was then evaluated aerobically using biometer assays and anaerobic bioassays. The experiments have shown that the acid (nitric acid) and base (sodium hydroxide) treatments are more efficient than the oxidants (potassium permanganate and catalyzed hydrogen peroxide) with respect to total organic carbon (TOC). The carbon contained in the solubilized/depolymerized product of nitric acid treatments accounted for approximately 14% of the carbon from the Powder River Basin (PRB) coal evaluated in the study; however, the biometer assays revealed that the bioavailability of the solubilized/depolymerized products was not directly correlated to the amount of dissolved organic carbon (TOC). The

  9. The use of erythropoiesis-stimulating agents with ruxolitinib in patients with myelofibrosis in COMFORT-II: an open-label, phase 3 study assessing efficacy and safety of ruxolitinib versus best available therapy in the treatment of myelofibrosis

    OpenAIRE

    McMullin, Mary Frances; Harrison, Claire N; Niederwieser, Dietger; Demuynck, Hilde; Jäkel, Nadja; Gopalakrishna, Prashanth; McQuitty, Mari; Stalbovskaya, Viktoriya; Recher, Christian; Theunissen, Koen; Gisslinger, Heinz; Kiladjian, Jean-Jacques; Al-Ali, Haifa-Kathrin

    2015-01-01

    BACKGROUND: Anemia is considered a negative prognostic risk factor for survival in patients with myelofibrosis. Most patients with myelofibrosis are anemic, and 35-54 % present with anemia at diagnosis. Ruxolitinib, a potent inhibitor of Janus kinase (JAK) 1 and JAK2, was associated with an overall survival benefit and improvements in splenomegaly and patient-reported outcomes in patients with myelofibrosis in the two phase 3 COMFORT studies. Consistent with the ruxolitinib mechanism of actio...

  10. Photo-stimulated electro-optic response of liquid-crystalline system with trans-cis photo-isomerizable agent

    International Nuclear Information System (INIS)

    A rather strong photo-stimulated enhancement of photo-induced bend flexoelectric effect based on trans-cis photoisomerization of azo bond was found in a guest-host system formed from the nematic liquid crystal (LC) N-(4-methoxybenzylidene)-4-butylaniline (MBBA) as a host, and the azobenzene LC 4-hexyloxybenzoloxy-4'-cyanoazobenzene, as a guest photoactive agent at 1 wt.% concentration. Upon application of electric field, thin homeotropic layers of thickness 100 pm containing this photo-sensitized LC mixture were investigated as subjected to a relatively weak illumination with UV light (λ = 375 nm, from narrow-band light-emitting diode, LED). The stimulation of the photoactive electro-optic response of azobenzene-doped MBBA (owing to enhanced photo-induced bend flexoelectric effect driven by the photo-isomerizable dopants) was achieved by pre-resonant excitation of the photoactive agent. The degree of the effect measured is of potential interest for thin-film photoactive electro-optic applications. The UV light-induced effect in azobenzene-doped MBBA was reversible; the back (relaxation) process was stimulated by light in the blue from a LED with broadband spectrum centered at 455 nm

  11. Numerical simulation to study the feasibility of using CO2 as a stimulation agent for enhanced geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Xu, T.; Zhang, W.; Pruess, K.

    2009-11-15

    A major concern in the development of enhanced geothermal systems (EGS) is achieving and maintaining adequate injectivity, while avoiding the development of preferential short-circuiting flow paths such as those caused by thermally-induced stress cracking. Past researches have tended to focus primarily on thermal and hydraulic stimulation. Recent studies suggest that chemical stimulation may improve the performance of EGS reservoirs. Geothermal injection wells are often drilled into formations containing reactive minerals such as calcite. Injecting aqueous chemical agents such as mineral acids, could be effective for mineral dissolution and porosity enhancement at distances of several meters around a well. An alternative to treatment with strong acids is the use of supercritical (SC) CO{sub 2} as stimulation agent for an aqueous-based EGS. Reactive transport modeling is used to investigate the effectiveness of this method. We used the thermal condition and mineralogical composition from a well of Desert Peak EGS site, to examine ways in which mixtures of water and CO{sub 2} can be injected to enhance porosity.

  12. β-Thalassemia and Polycythemia vera : Targeting chronic stress erythropoiesis

    NARCIS (Netherlands)

    Crielaard, Bart J; Rivella, Stefano

    2014-01-01

    β-Thalassemia and Polycythemia vera are genetic disorders which affect the synthesis of red blood cells, also referred to as erythropoiesis. Although essentially different in clinical presentation - patients with β-thalassemia have an impairment in β-globin synthesis leading to defective erythrocyte

  13. Inhibitors of Intracellular Signaling Pathways that Lead to Stimulated Epidermal Pigmentation: Perspective of Anti-Pigmenting Agents

    Directory of Open Access Journals (Sweden)

    Genji Imokawa

    2014-05-01

    Full Text Available Few anti-pigmenting agents have been designed and developed according to their known hyperpigmentation mechanisms and corresponding intracellular signaling cascades. Most anti-pigmenting agents developed so far are mechanistically involved in the interruption of constitutional melanogenic mechanisms by which skin color is maintained at a normal and unstimulated level. Thus, owing to the difficulty of confining topical application to a specific hyperpigmented skin area, potent anti-pigmenting agents capable of attenuating the natural unstimulated pigmentation process have the risk of leading to hypopigmentation. Since intracellular signaling pathways within melanocytes do not function substantially in maintaining normal skin color and are activated only by environmental stimuli such as UV radiation, specifically down-regulating the activation of melanogenesis to the constitutive level would be an appropriate strategy to develop new potent anti-pigmenting agents with a low risk of hypopigmentation. In this article, we review the hyperpigmentation mechanisms and intracellular signaling pathways that lead to the stimulation of melanogenesis. We also discuss a screening and evaluation system to select candidates for new anti-melanogenic substances by focusing on inhibitors of endothelin-1 or stem cell factor-triggered intracellular signaling cascades. From this viewpoint, we show that extracts of the herbs Withania somnifera and Melia toosendan and the natural chemicals Withaferin A and Astaxanthin are new candidates for potent anti-pigmenting substances that avoid the risk of hypopigmentation.

  14. Enzymatic Debriding Agents Are Safe in Wounds With High Bacterial Bioburdens and Stimulate Healing

    OpenAIRE

    Payne, Wyatt G.; Salas, R. Emerick; Ko, Francis; Naidu, Deepak K.; Donate, Guillermo; Wright, Terry E.; Robson, Martin C.

    2008-01-01

    Background: Debridement is essential for successful wound management. Enzymatic debridement is commonly utilized in wound care but has been reported to be unsafe in wounds with significant bacterial bioburden, unless used in conjunction with topical antimicrobials. We examine this hypothesis with 2 commercially available, commonly used preparations of enzymatic debriding agents. Materials and Methods: Using a standard rodent model of a chronically infected granulating wound with bacterial lev...

  15. β-Thalassemia and Polycythemia vera: targeting chronic stress erythropoiesis

    OpenAIRE

    Crielaard, Bart J.; Rivella, Stefano

    2014-01-01

    β-thalassemia and Polycythemia vera are genetic disorders which affect the synthesis of red blood cells, also referred to as erythropoiesis. Although essentially different in clinical presentation – patients with β-thalassemia have an impairment in β-globin synthesis leading to defective erythrocytes and anemia, while patients with Polycythemia vera present with high hemoglobin levels because of excessive red blood cell synthesis – both pathologies may characterized by lasting high erythropoi...

  16. ETO2 coordinates cellular proliferation and differentiation during erythropoiesis

    OpenAIRE

    Goardon, Nicolas; Lambert, Julie A; Rodriguez, Patrick; Nissaire, Philippe; Herblot, Sabine; Thibault, Pierre; Dumenil, Dominique; Strouboulis, John; Romeo, Paul-Henri; Hoang, Trang

    2006-01-01

    The passage from proliferation to terminal differentiation is critical for normal development and is often perturbed in malignancies. To define the molecular mechanisms that govern this process during erythropoiesis, we have used tagging/proteomics approaches and characterized protein complexes nucleated by TAL-1/SCL, a basic helix–loop–helix transcription factor that specifies the erythrocytic lineage. In addition to known TAL-1 partners, GATA-1, E2A, HEB, LMO2 and Ldb1, we identify the ETO2...

  17. In-vitro studies of ineffective erythropoiesis in rheumatoid arthritis

    OpenAIRE

    Williams, R A; Samson, Diana; Tikerpae, J.; Crowne, Helen; Gumpel, J M

    1982-01-01

    Ineffective erythropoiesis was assessed in a series of 32 patients with rheumatoid arthritis by means of a new in-vitro method which measures the release of haem from a labelled cohort of erythroblasts in culture. Haem release was significantly increased in patients with the anaemia of chronic disorders but was normal in those who were not anaemic or who had an iron-deficiency anaemia. In 2 patients with anaemia of chronic disorders haem release returned to normal after successful antirheumat...

  18. Quercetin Affects Erythropoiesis and Heart Mitochondrial Function in Mice

    Directory of Open Access Journals (Sweden)

    Lina M. Ruiz

    2015-01-01

    Full Text Available Quercetin, a dietary flavonoid used as a food supplement, showed powerful antioxidant effects in different cellular models. However, recent in vitro and in vivo studies in mammals have suggested a prooxidant effect of quercetin and described an interaction with mitochondria causing an increase in O2∙- production, a decrease in ATP levels, and impairment of respiratory chain in liver tissue. Therefore, because of its dual actions, we studied the effect of quercetin in vivo to analyze heart mitochondrial function and erythropoiesis. Mice were injected with 50 mg/kg of quercetin for 15 days. Treatment with quercetin decreased body weight, serum insulin, and ceruloplasmin levels as compared with untreated mice. Along with an impaired antioxidant capacity in plasma, quercetin-treated mice showed a significant delay on erythropoiesis progression. Heart mitochondrial function was also impaired displaying more protein oxidation and less activity for IV, respectively, than no-treated mice. In addition, a significant reduction in the protein expression levels of Mitofusin 2 and Voltage-Dependent Anion Carrier was observed. All these results suggest that quercetin affects erythropoiesis and mitochondrial function and then its potential use as a dietary supplement should be reexamined.

  19. Detection of Chemical/Biological Agents and Stimulants using Quadrupole Ion Trap Mass Spectrometry

    International Nuclear Information System (INIS)

    Detection of Chemical/Biological Agents and Simulants A new detector for chemical and biological agents is being developed for the U. S. Army under the Chemical and Biological Mass Spectrometer Block II program. The CBMS Block II is designed to optimize detection of both chemical and biological agents through the use of direct sampling inlets[I], a multi- ported sampling valve and a turbo- based vacuum system to support chemical ionization. Unit mass resolution using air as the buffer gas[2] has been obtained using this design. Software to control the instrument and to analyze the data generated from the instrument has also been newly developed. Detection of chemical agents can be accomplished. using the CBMS Block II design via one of two inlets - a l/ I 6'' stainless steel sample line -Chemical Warfare Air (CW Air) or a ground probe with enclosed capillary currently in use by the US Army - CW Ground. The Block II design is capable of both electron ionization and chemical ionization. Ethanol is being used as the Cl reagent based on a study indicating best performance for the Biological Warfare (BW) detection task (31). Data showing good signal to noise for 500 pg of methyl salicylate injected into the CW Air inlet, 50 ng of dimethylmethylphosphonate exposed to the CW Ground probe and 5 ng of methyl stearate analyzed using the pyrolyzer inlet were presented. Biological agents are sampled using a ''bio-concentrator'' unit that is designed to concentrate particles in the low micron range. Particles are collected in the bottom of a quartz pyrolyzer tube. An automated injector is being developed to deliver approximately 2 pL of a methylating reagent, tetramethylamonium- hydroxide to 'the collected particles. Pyrolysis occurs by rapid heating to ca. 55OOC. Biological agents are then characterized by their fatty acid methyl ester profiles and by other biomarkers. A library of ETOH- Cl/ pyrolysis MS data of microorganisms used for a recently published study[3] has been

  20. DNA-damaging agents stimulate gene expression at specific loci in Escherichia coli

    International Nuclear Information System (INIS)

    Operon fusions in Escherichia coli were obtained that showed increased beta-galactosidase expression in response to treatment with the DNA-damaging agent mitomycin C. These fusions were generated by using the Mud(ApR, lac) vector to insert the lactose structural genes randomly into the bacterial chromosome. Induction of beta-galactosidase in these strains, which carried fusions of lac to these din (damage-inducible) loci, was (i) triggered by UV light as well as by mitomycin C and (ii) abolished by either a recA- or a lexA- mutation. Similar characteristics of induction were observed when the lactose genes were fused to a prophage lambda promoter by using Mud(ApR, lac). These results indicate that E. coli contains a set of genes that, like prophage lambda genes, are expressed in response to DNA-damaging agents and regulated by the recA and lexA gene products. These din genes map at five bacterial loci. One din::Mud(ApR, lac) insertion results in a UV-sensitive phenotype and may be within the uvrA transcriptional unit

  1. Effects of Testosterone on Erythropoiesis in a Female Mouse Model of Anemia of Inflammation.

    Science.gov (United States)

    Guo, Wen; Schmidt, Paul J; Fleming, Mark D; Bhasin, Shalender

    2016-07-01

    The anemia of inflammation is a common problem in inflammatory and autoimmune diseases. We characterized a mouse model of anemia of chronic inflammation induced by repeated injections of low doses of heat-killed Brucella abortus (HKBA), and determined the effects of T administration on erythropoiesis in this model. Female C57BL/6NCrl mice were injected weekly with HKBA for 10 wk. Weekly injections of T or vehicle oil were started 4 wk later. Control mice were injected with saline and vehicle oil in parallel. HKBA-injected mice had significantly lower hemoglobin, hematocrit, mean corpuscular volume, reticulocyte hemoglobin, transferrin saturation (TSAT), and tissue nonheme iron in liver and spleen, enlarged spleen, and up-regulated hepatic expression of inflammatory markers, serum amyloid A1, and TNFα, but down-regulated IL-6, bone morphogenic protein 6, and hepcidin compared with saline controls. HKBA also reduced serum hepcidin and increased serum erythropoietin. Bone marrow erythroid precursors were substantially reduced in HKBA-injected mice. Cotreatment with T increased the percentage of late-stage erythroid precursors in the bone marrow relative to HKBA-injected and saline controls and reversed HKBA-induced suppression of hemoglobin and hematocrit. T also normalized serum erythropoietin, TSAT, and reticulocyte hemoglobin without correcting the expression of the hepatic inflammation markers. Conclusions are that low-dose HKBA induces moderate anemia characterized by chronic inflammation, decreased iron stores, and suppression of erythroid precursors in the bone marrow. T administration reverses HKBA-induced anemia by stimulating erythropoiesis, which is associated with a shift toward accelerated maturation of erythroid precursors in the bone marrow. PMID:27074351

  2. Pharmacology of kratom: an emerging botanical agent with stimulant, analgesic and opioid-like effects.

    Science.gov (United States)

    Prozialeck, Walter C; Jivan, Jateen K; Andurkar, Shridhar V

    2012-12-01

    Kratom (Mitragyna speciosa) is a plant indigenous to Thailand and Southeast Asia. Kratom leaves produce complex stimulant and opioid-like analgesic effects. In Asia, kratom has been used to stave off fatigue and to manage pain, diarrhea, cough, and opioid withdrawal. Recently, kratom has become widely available in the United States and Europe by means of smoke shops and the Internet. Analyses of the medical literature and select Internet sites indicate that individuals in the United States are increasingly using kratom for the self-management of pain and opioid withdrawal. Kratom contains pharmacologically active constituents, most notably mitragynine and 7-hydroxymitragynine. Kratom is illegal in many countries. Although it is still legal in the United States, the US Drug Enforcement Administration has placed kratom on its "Drugs and Chemicals of Concern" list. Physicians should be aware of the availability, user habits, and health effects of kratom. Further research on the therapeutic uses, toxic effects, and abuse potential of kratom and its constituent compounds are needed. PMID:23212430

  3. BEBIDAS ENERGIZANTES: ¿HIDRATANTES O ESTIMULANTES? Energy drinks: rehydrating agents or stimulants?

    Directory of Open Access Journals (Sweden)

    Miguel Cote-Menéndez

    2011-09-01

    .Background. Energy drinks can be found almost everywhere; their consumption has increased due to ease of access to them, their stimulant properties and the idea that they are harmless. Scarce knowledge about their characteristics has led to them being confused with rehydrating drinks and thus their indiscriminate use, even though rehydrating drinks seek to prevent dehydration and energy drinks have a stimulant effect. Objective. Describing energy drinks' components and analysing their effects, undesired reactions and precautions regarding their use. Materials and methods. The literature in Pubmed was reviewed using the MeSH terms «caffeine» OR «taurine» OR «gluconates» combined with the term «energy drinks» with specifiers, 42 articles being found. The summaries were analysed and 29 articles were included in the study. Results. Energy drinks contain methylxanthines, carbohydrates, taurine, vitamins and/or guaraná (caffeine source from an Amazon region berry. Most stimulant effects happen at the expense of high concentrations of methylxanthines such as caffeine. Such high concentrations increase the risk of poisoning and caffeine dependence. Cases of arrhythmia, heart attack, exacerbation of psychiatric symtomatology and convulsions associated with their consumption have been reported. Furthermore, mixing them with alcohol increases alcohol poisoning-related damage. They are not recommended for sportspeople due to their diuretic and cardiovascular effects. Conclusions. It has been shown that energy drink components are not completely innocuous. Even though their chronic effects remain unknown, the literature does warn about the damage to health which could be caused by strong acute consumption or frequent consumption. Measures must thus be implemented which are aimed at broadcasting the consequences of these substances and restricting their consumption by atrisk populations.

  4. Standards and options: recommendations for the use of erythropoiesis-stimulating agents (ESA) in anemic cancer patients undergoing radiotherapy (2007 update); Standards, options: recommandations 2007. Indication des agents stimulants l'erythropoiese (ASE) dans la prise en charge de l'anemie induite par la radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Marchal, Ch. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Misset, J.L. [Hopital Saint-Louis, 75 - Paris (France); Casadevall, N. [Hopital Saint Antoine, 75 - Paris (France); Marec-Berard, P.; Ray-Coquard, I. [Centre de Lutte Contre le Cancer Leon-Berard, 69 - Lyon (France); Chastagner, P. [Hopital d' Enfants Nancy, 54 (France); Kassab-Chahmi, D. [Federation Nationale des Centres de Lutte Contre le Cancer (FNCLCC), 75 - Paris (France)

    2008-03-15

    Introduction. - Beginning 1998, a working group of specialists convened by the guidelines department (Standards, Options and Recommendations: S.O.R.) of the National French Federation of Comprehensive Cancer Centres (F.N.C.L.C.C.) published then regularly updated Recommendations relative to the use of ESA (epoetin alfa, epoetin beta, darbepoetin) in anemic patients with cancer. This article presents the updated Recommendations set up in 2007. Methods. - This updating process is based on the methodology developed and used in the 'Standards, Options: Recommendations' programme. The methodological approach combines systematic review with the judgement of a multidisciplinary group of experts. On the basis of analysis of literature, the conclusions and their level of evidence are established. Then, the conclusions accompanied by experts judgement lead to the Recommendations. A Recommendation is a proposal of one or several clinical attitudes intended to improve cancer patient care. Before publication, the R.P.C.-S.O.R. are re-examined by independent reviewers selected according to the same principles as the group of expert writers. Results. - New data, relative to the 'use of ESA in anemic cancer patients undergoing radiotherapy', did not lead to update the latest Recommendations validated in 2003. However, new data relative to the 'use of ESA in anaemia prophylaxis among adult patients with cancer' and to the 'use of iron with ESA in cancer patients' were sufficient to generate either major or minor modifications to the initial Recommendations. Conclusions. - Thus, it appears relevant to re-examine these Recommendations according to a systematic monitoring process which should be renewed in two years. (authors)

  5. Ineffective erythropoiesis and regulation of iron status in iron loading anaemias.

    Science.gov (United States)

    Camaschella, Clara; Nai, Antonella

    2016-02-01

    The definition 'iron loading anaemias' encompasses a group of inherited and acquired anaemias characterized by ineffective erythropoiesis, low hepcidin levels, excessive iron absorption and secondary iron overload. Non-transfusion-dependent β-thalassaemia is the paradigmatic example of these conditions that include dyserythropoietic and sideroblastic anaemias and some forms of myelodysplasia. Interrupting the vicious cycle between ineffective erythropoiesis and iron overload may be of therapeutic benefit in all these diseases. Induction of iron restriction by means of transferrin infusions, minihepcidins or manipulation of the hepcidin pathway prevents iron overload, redistributes iron from parenchymal cells to macrophage stores and partially controls anaemia in β-thalassaemic mice. Inhibition of ineffective erythropoiesis by activin ligand traps improves anaemia and iron overload in the same models. Targeting iron loading or ineffective erythropoiesis shows promise in preclinical studies; activin ligand traps are in clinical trials with promising results and may be useful in patients with ineffective erythropoiesis. PMID:26491866

  6. Dexamethasone facilitates erythropoiesis in murine embryonic stem cells differentiating into hematopoietic cells in vitro

    International Nuclear Information System (INIS)

    Differentiating embryonic stem (ES) cells are increasingly emerging as an important source of hematopoietic progenitors with a potential to be useful for both basic and clinical research applications. It has been suggested that dexamethasone facilitates differentiation of ES cells towards erythrocytes but the mechanism responsible for sequential expression of genes regulating this process are not well-understood. Therefore, we in vitro induced differentiation of murine ES cells towards erythropoiesis and studied the sequential expression of a set of genes during the process. We hypothesized that dexamethasone-activates its cognate nuclear receptors inducing up-regulation of erythropoietic genes such as GATA-1, Flk-1, Epo-R, and direct ES cells towards erythropoietic differentiation. ES cells were cultured in primary hematopoietic differentiation media containing methyl-cellulose, IMDM, IL-3, IL-6, and SCF to promote embryoid body (EB) formation. Total RNA of day 3, 5, and 9-old EBs was isolated for gene expression studies using RT-PCR. Cells from day 9 EBs were subjected to secondary differentiation using three different cytokines and growth factors combinations: (1) SCF, EPO, dexamethasone, and IGF; (2) SCF, IL-3, IL-6, and TPO; and (3) SCF IL-3, IL-6, TPO, and EPO. Total RNA from day 12 of secondary differentiated ES cells was isolated to study the gene expression pattern during this process. Our results demonstrate an up-regulation of GATA-1, Flk-1, HoxB-4, Epo-R, and globin genes (α-globin, βH-1 globin, β-major globin, ε -globin, and ζ-globin) in the 9-day-old EBs, whereas, RNA from 5-day-old EBs showed expression of HoxB-4, ε-globin, γ-globin, βH1-globin, and Flk-1. Three-day-old EBs showed only HoxB-4 and Flk-1 gene expression and lacked expression of all globin genes. These findings indicate that erythropoiesis-specific genes are activated later in the course of differentiation. Gene expression studies on the ES cells of secondary EB origin cultured

  7. Potential Manipulations to Restore Aberrant Myelopoiesis: The Role of New Colony-Stimulating Factors and other Agents

    OpenAIRE

    1992-01-01

    A rapidly growing number of new recombinant human colony-stimulating factors (CSFs) are entering various phases of clinical testing. With the recent approval of granulocyte colony-stimulating factor (G-CSF) and granulocytemacrophage colony-stimulating factor (GM-CSF) for clinical use, newer CSFs will be developed for a widening spectrum of disease states singularly and in combination with other CSFs. Interleukin (IL)-3 is being tested in early clinical trials, and combination studies with G-C...

  8. Macrophages support pathological erythropoiesis in Polycythemia Vera and Beta-Thalassemia

    OpenAIRE

    Ramos, Pedro; Casu, Carla; Gardenghi, Sara; Breda, Laura; Crielaard, Bart J.; Guy, Ella; Marongiu, Maria Franca; Gupta, Ritama; Levine, Ross L; Abdel-Wahab, Omar; Benjamin L Ebert; van Rooijen, Nico; Ghaffari, Saghi; Grady, Robert W.; Giardina, Patricia J.

    2013-01-01

    Regulation of erythropoiesis is achieved by integration of distinct signals. Among these, macrophages are emerging as erythropoietin-complementary regulators of erythroid development, particularly under stress conditions. We investigated the contribution of macrophages for physiological and pathological conditions of enhanced erythropoiesis. We utilized mouse models of induced anemia, Polycythemia vera and β-thalassemia in which macrophages were chemically depleted. Our data indicate that mac...

  9. Inhibition of DNA fragmentation in thymocytes and isolated thymocyte nuclei by agents that stimulate protein kinase C.

    Science.gov (United States)

    McConkey, D J; Hartzell, P; Jondal, M; Orrenius, S

    1989-08-15

    Glucocorticoid hormones and Ca2+ ionophores stimulate a suicide process in immature thymocytes, known as apoptosis or programmed cell death, that involves extensive DNA fragmentation. We have recently shown that a sustained increase in cytosolic Ca2+ concentration stimulates DNA fragmentation and cell killing in glucocorticoid- or ionophore-treated thymocytes. However, a sustained increase in the cytosolic Ca2+ level also mediates lymphocyte proliferation, suggesting that apoptosis is blocked in proliferating thymocytes. In this study we report that phorbol esters, which selectively stimulate protein kinase C (PKC), blocked DNA fragmentation and cell death in thymocytes exposed to Ca2+ ionophore or glucocorticoid hormone. The T cell mitogen, concanavalin A, which stimulates thymocytes by a mechanism that involves PKC activation, caused concentration-dependent increases in the cytosolic Ca2+ level that did not result in DNA fragmentation, but incubation with concanavalin A and the PKC inhibitor H-7 (1-(5-isoquinolinylsulfonyl)-2-methylpiperazine) resulted in both DNA fragmentation and cell death. Phorbol ester directly inhibited Ca2+-dependent DNA fragmentation in isolated thymocyte nuclei. Our results strongly suggest that PKC activation blocks thymocyte apoptosis by preventing Ca2+-stimulated endonuclease activation. PMID:2503500

  10. Expression of ABCG2 (BCRP in mouse models with enhanced erythropoiesis

    Directory of Open Access Journals (Sweden)

    Gladys Oluyemisi Latunde-Dada

    2014-06-01

    Full Text Available Haem is a structural component of numerous cellular proteins which contributes significantly to iron metabolic processes in mammals but its toxicity demands that cellular levels must be tightly regulated. Breast Cancer Resistance Protein (BCRP/ABCG2, an ATP Binding Cassette G-member protein has been shown to possess porhyrin/haem efflux function. The current study evaluated the expression and regulation of Abcg2 mRNA and protein levels in mouse tissues involved in erythropoiesis. Abcg2 mRNA expression was enhanced in bone marrow hemopoietic progenitor cells from mice that were treated with phenylhydrazine (PHZ. Abcg2 mRNA expression was increased particularly in the extramedullary haematopoietic tissues from all the mice models with enhanced erythropoiesis. Haem oxygenase (ho1 levels tended to increase in the liver of mice with enhanced erythropoiesis and gene expression patterns differed from those observed in the spleen. Efflux of haem biosynthetic metabolites might be dependent on the relative abundance of Abcg2 or ho1 during erythropoiesis. Abcg2 appears to act principally as a safety valve regulating porphyrin levels during the early stages of erythropoiesis and its role in systemic haem metabolism and erythrophagocytosis, in particular, awaits further clarification.

  11. New advances in the treatment of adult chronic immune thrombocytopenic purpura: role of thrombopoietin receptor-stimulating agents

    Directory of Open Access Journals (Sweden)

    Ara Metjian

    2009-12-01

    Full Text Available Ara Metjian1, Charles S Abrams21Department of Medicine, Duke University Medical Center, Durham, NC, USA; 2Department of Medicine, University of Pennsylvania, Philadelphia, PA, USAAbstract: Decades of basic science and clinical research have led to an increased understanding of the pathophysiology of immune thrombocytopenic purpura (ITP, the processes underlying thrombopoiesis, and the treatment of chronic ITP. Now, new agents are available to treat ITP in a nonimmunosuppressive fashion. Lessons learned from the clinical trials of recombinant human thrombopoietin (TPO have led to the development of a novel class of compounds: nonimmunogenic agonists of the thrombopoietin receptor. Representing the first nonimmunosuppressive agents to treat chronic refractory ITP in decades, medications such as romiplostim and eltrombopag were recently approved by the US Food and Drug Administration. These new agents offer physicians a new tool for treating difficult cases of ITP in their medical armamentarium. Additional TPO mimetics are also being developed that show promise in vitro, and await future development.Keywords: thrombocytopenia, immune-mediated thrombocytopenia, eltrombopag, romiplostim, thrombopoietin, thrombopoietin receptor

  12. Ciprofloxacin Enhances Stress Erythropoiesis in Spleen and Increases Survival after Whole-Body Irradiation Combined with Skin-Wound Trauma

    Science.gov (United States)

    Fukumoto, Risaku; Burns, True M.; Kiang, Juliann G.

    2014-01-01

    Severe hematopoietic loss is one of the major therapeutic targets after radiation-combined injury (CI), a kind of injury resulting from radiation exposure combined with other traumas. In this study, we tested the use of ciprofloxacin (CIP) as a treatment, because of recently reported immunomodulatory effects against CI that may improve hematopoiesis. The CIP regimen was a daily, oral dose for 3 weeks, with the first dose 2 h after CI. CIP treatment improved 30-day survival in mice at 80% compared to 35% for untreated controls. Study of early changes in hematological parameters identified CI-induced progressive anemia by 10 days that CIP significantly ameliorated. CI induced erythropoietin (EPO) mRNA in kidney and protein in kidney and serum; CIP stimulated EPO mRNA expression. In spleens of CI mice, CIP induced bone morphogenetic protein 4 (BMP4) in macrophages with EPO receptors. Splenocytes from CIP-treated CI mice formed CD71+ colony-forming unit-erythroid significantly better than those from controls. Thus, CIP-mediated BMP4-dependent stress erythropoiesis may play a role in improving survival after CI. PMID:24587369

  13. [Evaluation of erythropoiesis under the influence of recombinant human erythropoietin (R-EPO) in dialyzed patients].

    Science.gov (United States)

    Debska-Slizień, A; Kabata, J; Rutkowski, B; Ciesielski, D; Jankowska-Gan, E; Manitius, A

    1991-06-01

    5 deeply anemic (Hb less than 8 g/dl, Ht less than 25%) dialyzed patients with chronic renal failure were treated during four months with r-Epo. Blood cells morphological parameters were estimated using hematological autoanalyser Technicon H1. Satisfactory increase of the Hb levels and RBC counts were observed in 4 patients, in one the improvement was insignificant. We observed three types of response to r-Epo treatment: 1) macrocytic type, 2) hypochromic type, and 3) non-hypochromic type, without lasting macrocytosis. Our results suggest that type of erythropoiesis depends on other active biological substances (iron, folic acid, vit. B12) necessary for correcting erythropoiesis. r-Epo administration appeared to be a safe and effective method of anaemia treatment in dialyzed patients. Its administration eliminated blood transfusion for six months. PMID:1896397

  14. Evolutionary suppression of erythropoiesis via the modulation of TGF-β signalling in an Antarctic icefish.

    Science.gov (United States)

    Xu, Qianghua; Cai, Chang; Hu, Xingxing; Liu, Yun; Guo, Yanan; Hu, Peng; Chen, Zuozhou; Peng, Sihua; Zhang, Dongsheng; Jiang, Shouwen; Wu, Zhichao; Chan, Jiulin; Chen, Liangbiao

    2015-09-01

    The Antarctic icefish, a family (Channichthyidae) of teleosts within the perciform suborder Notothenioidei, are the only known vertebrates without oxygen-transporting haemoglobins and that are largely devoid of circulating erythrocytes. To elucidate the evo-devo mechanisms underpinning the suppressed erythropoiesis in the icefish, we conducted comparative studies on the transcriptomes and microRNAomes of the primary haematopoietic tissues between an icefish (Chionodraco hamatus) and two red-blooded notothenioids (Trematomus bernacchii and Gymnodraco acuticeps). We identified substantial remodelling of the haematopoietic programs in the icefish through which erythropoiesis is selectively suppressed. Experimental verification showed that erythropoietic suppression in the icefish may be attributable to the upregulation of TGF-β signalling, which coincides with reductions in multiple transcription factors essential for erythropoiesis and the upregulation of hundreds of microRNAs, the majority (> 80%) of which potentially target erythropoiesis regulating factors. Of the six microRNAs selected for verification, three miRNAs (miR-152, miR-1388 and miR-16b) demonstrated suppressive functions on GATA1 and ALAS2, which are two factors important for erythroid differentiation, resulting in reduced numbers of erythroids in microinjected zebra fish embryos. Codon substitution analyses of the genes of the TGF-β superfamily revealed signs of positive selection in TGF-β1 and endoglin in the lineages leading to Antarctic notothenioids. Both genes are previously known to function in erythropoietic suppression. These findings implied a general trend of erythropoietic suppression in the cold-adapted notothenioid lineages through evolutionary modulation of the multi-functional TGF-β signalling pathway. This trend is more pronounced in the haemoglobin-less icefish, which may pre-emptively hinder the otherwise defective erythroids from production. PMID:26268413

  15. Aconitase regulation of erythropoiesis correlates with a novel licensing function in erythropoietin-induced ERK signaling.

    Directory of Open Access Journals (Sweden)

    Anne-Laure Talbot

    Full Text Available BACKGROUND: Erythroid development requires the action of erythropoietin (EPO on committed progenitors to match red cell output to demand. In this process, iron acts as a critical cofactor, with iron deficiency blunting EPO-responsiveness of erythroid progenitors. Aconitase enzymes have recently been identified as possible signal integration elements that couple erythropoiesis with iron availability. In the current study, a regulatory role for aconitase during erythropoiesis was ascertained using a direct inhibitory strategy. METHODOLOGY/PRINCIPAL FINDINGS: In C57BL/6 mice, infusion of an aconitase active-site inhibitor caused a hypoplastic anemia and suppressed responsiveness to hemolytic challenge. In a murine model of polycythemia vera, aconitase inhibition rapidly normalized red cell counts, but did not perturb other lineages. In primary erythroid progenitor cultures, aconitase inhibition impaired proliferation and maturation but had no effect on viability or ATP levels. This inhibition correlated with a blockade in EPO signal transmission specifically via ERK, with preservation of JAK2-STAT5 and Akt activation. Correspondingly, a physical interaction between ERK and mitochondrial aconitase was identified and found to be sensitive to aconitase inhibition. CONCLUSIONS/SIGNIFICANCE: Direct aconitase inhibition interferes with erythropoiesis in vivo and in vitro, confirming a lineage-selective regulatory role involving its enzymatic activity. This inhibition spares metabolic function but impedes EPO-induced ERK signaling and disturbs a newly identified ERK-aconitase physical interaction. We propose a model in which aconitase functions as a licensing factor in ERK-dependent proliferation and differentiation, thereby providing a regulatory input for iron in EPO-dependent erythropoiesis. Directly targeting aconitase may provide an alternative to phlebotomy in the treatment of polycythemia vera.

  16. Effect of inflammation induced by prolonged exercise on circulating erythroid progenitors and markers of erythropoiesis

    OpenAIRE

    Premetis, Evangelos; Skenderi, Katerina; Graphakos, Stelios; Baltopoulos, Panayiotis; Tsironi, Maria; Papassotiriou, Ioannis

    2009-01-01

    Background: Exercise in humans augments the mobilization of circulating hematopoietic progenitor cells (CD34+) from the bone marrow. We investigated the effect of inflammation on erythroid marrow activity by mobilization of erythroid progenitor cells (EPs) along with soluble markers of erythropoiesis. Methods: Ten healthy athletes who participated in an ultradistance foot race participated in the study. Peripheral blood mononuclear cells were isolated, before (phase I), at the end (phase II)...

  17. Interleukin-2 critically regulates bone marrow erythropoiesis and prevents anemia development.

    Science.gov (United States)

    Chopra, Martin; Langenhorst, Daniela; Beilhack, Andreas; Serfling, Edgar; Patra, Amiya K

    2015-12-01

    Mice deficient in IL-2 signaling develop severe anemia indicating a defect in erythropoiesis. However, why deficiency in IL-2, an essential growth factor for lymphocytes, or in IL-2 signaling components should result in defective erythropoiesis is unclear. Here, we have analyzed the mechanism of IL-2 signaling deficiency induced anemia in mice and show that IL-2 plays an indispensable role in bone marrow (BM) erythropoiesis via maintenance of regulatory T (Treg) cells. In absence of IL-2 signaling, IFN-γ produced by the activated T cells suppressed klf1 expression, resulting in an early block in erythrocyte differentiation. Anemia, in IL-2 or IL-2 signaling deficient mice always developed prior to the manifestation of other autoimmune complications such as colitis, suggesting that anemia in these mice might be a contributing factor in inducing other pathological complications in later stages. Our study shows, how essential cytokines of lymphoid cells could exert critical influence on the development of erythrocytes and thus expanding our understanding of the complex regulation of hematopoiesis in the BM. Besides, our findings might facilitate the use of IL-2 and anti-IFN-γ as a clinical remedy against anemia that arise in cancer patients following radiotherapy or chemotherapy, a context which simulates the situation of IL-2 deficiency. PMID:26404745

  18. Recombinant human erythropoietin-induced erythropoiesis regulates hepcidin expression over iron status in the rat.

    Science.gov (United States)

    Ribeiro, Sandra; Garrido, Patrícia; Fernandes, João; Rocha, Susana; Rocha-Pereira, Petronila; Costa, Elísio; Belo, Luís; Reis, Flávio; Santos-Silva, Alice

    2016-07-01

    The crosstalk between several factors controlling hepcidin synthesis is poorly clarified for different physiological and pathological conditions. Our aim was to study the impact of increasing recombinant human erythropoietin (rHuEPO) doses on erythropoiesis, iron metabolism and hepcidin, using a rat model. Male Wistar rats were divided in 5 groups: control (vehicle) and rHuEPO-treated groups (100, 200, 400 and 600IU/kgbody weight/week), 3 times per week, during 3weeks. Hematological and iron data were evaluated. The expression of several genes involved in iron metabolism was analyzed by qPCR. Liver hepcidin protein was evaluated by Western Blot. The rHuEPO treatment induced erythropoiesis and increased transferrin saturation (TSAT) in a dose dependent manner. Tf receptor 2 (TfR2), hemojuvelin (HJV) and bone morphogenetic protein 6 (BMP6) were up-regulated in rHuEPO200 group. Matriptase-2 was down-regulated in rHuEPO200 group, and up-regulated in the other rHuEPO-treated groups. Hepcidin synthesis was increased in rHuEPO200 group, and repressed in the rHuEPO400 and rHuEPO600 groups. Our study showed that when a high erythropoietic stimulus occurs, hepcidin synthesis is mainly regulated by TSAT; however, when the erythropoiesis rate reaches a specific threshold, extramedullary hematopoiesis is triggered, and the control of hepcidin synthesis is switched to matriptase-2, thus inhibiting hepcidin synthesis. PMID:27282570

  19. p38α controls erythroblast enucleation and Rb signaling in stress erythropoiesis

    Institute of Scientific and Technical Information of China (English)

    Simon M Schultze; Andreas Mairhofer; Dan Li; Jin Cen; Hartmut Beug; Erwin F Wagner; Lijian Hui

    2012-01-01

    Enucleation of erythroblasts during terminal differentiation is unique to mammals.Although erythroid enucleation has been extensively studied,only a few genes,including retinoblastoma protein(Rb),have been identified to regulate nuclear extrusion.It remains largely undefined by which signaling molecules,the extrinsic stimuli,such as erythropoietin(Epo),are transduced to induce enucleation.Here,we show that p38α,a mitogen-activated protein kinase(MAPK),is required for erythroid enucleation.In an ex vivo differentiation system that contains high Epo levels and mimics stress erythropoiesis,p38α is activated during erythroid differentiation.Loss of p38α completely blocks enucleation of primary erythroblasts.Moreover,p38α regulates erythroblast enucleation in a cell-autonomous manner in vivo during fetal and anemic stress erythropoiesis.Markedly,loss of p38α leads to downregulation of p21,and decreased activation of the p21 target Rb,both of which are important regulators of erythroblast enucleation.This study demonstrates that p38α is a key signaling molecule for erythroblast enucleation during stress erythropoiesis.

  20. Living high-training low: effect on erythropoiesis and maximal aerobic performance in elite Nordic skiers

    DEFF Research Database (Denmark)

    Robach, P.; Schmitt, L.; Brugniaux, J.V.;

    2006-01-01

    The "living high-training low" model (Hi-Lo) may improve aerobic performance in athletes, and the main mechanism of this improvement is thought to be augmented erythropoiesis. A positive effect of Hi-Lo has been demonstrated previously by using altitudes of 2,000-3,000 m. Since the rate of...... erythropoiesis is altitude-dependent, we tested whether a higher altitude (3,500 m) during Hi-Lo increases erythropoiesis and maximal aerobic performance. Nordic skiers trained for 18 days at 1,200 m, while sleeping at 1,200 m in ambient air (control group, n = 5) or in hypoxic rooms (Hi-Lo, n = 6; 3 x 6 days at...... simulated altitudes of 2,500, 3,000 and finally 3,500 m, 11 h day(-1)). Measurements were done before, during (blood samples only) and 2 weeks after the intervention (POST). Maximal aerobic performance was examined from VO(2max) and time to exhaustion (T(exh)) at vVO(2max) (minimum speed associated with VO...

  1. Retrospective study of reticulocyte indices as indicators of iron-restricted erythropoiesis in dogs with immune-mediated hemolytic anemia.

    Science.gov (United States)

    Schaefer, Deanna M W; Stokol, Tracy

    2016-05-01

    Iron-restricted erythropoiesis can occur as a result of an absolute deficiency of iron stores, inflammation-mediated iron sequestration, or functional iron deficiency (in which release of stored iron is slower than the iron uptake by erythroid precursors during intense erythropoiesis). Reticulocyte indices are used to identify iron-restricted erythropoiesis, with the reticulocyte hemoglobin content (CHr) being the most commonly used index in human patients. Dogs with immune-mediated hemolytic anemia (IMHA) may have iron-restricted erythropoiesis caused by inflammation-mediated iron sequestration and/or functional iron deficiency, which could contribute to anemia severity and blunt the regenerative response in some dogs. To investigate this possibility, reticulocyte indices were examined retrospectively in 14 dogs (2-15 years of age; 9 spayed females, 1 intact female, 4 neutered males) with IMHA, and no clinical evidence of blood loss was found to suggest absolute iron deficiency. Five dogs (34%) had CHr below the preestablished lower reference limit (24.5 pg), and hematocrit was significantly lower in these dogs (p = 0.042, nonpaired t-test). Our results suggest that some dogs with IMHA may have iron-restricted erythropoiesis as a result of functional iron deficiency, inflammation-mediated iron sequestration, or (less likely) absolute iron deficiency. Further study is warranted to evaluate if dogs with IMHA may benefit from parenteral iron therapy. PMID:27034340

  2. Leishmania donovani infection induces anemia in hamsters by differentially altering erythropoiesis in bone marrow and spleen.

    Directory of Open Access Journals (Sweden)

    William P Lafuse

    Full Text Available Leishmania donovani is a parasite that causes visceral leishmaniasis by infecting and replicating in macrophages of the bone marrow, spleen, and liver. Severe anemia and leucopenia is associated with the disease. Although immune defense mechanisms against the parasite have been studied, we have a limited understanding of how L. donovani alters hematopoiesis. In this study, we used Syrian golden hamsters to investigate effects of L. donovani infection on erythropoiesis. Infection resulted in severe anemia and leucopenia by 8 weeks post-infection. Anemia was associated with increased levels of serum erythropoietin, which indicates the hamsters respond to the anemia by producing erythropoietin. We found that infection also increased numbers of BFU-E and CFU-E progenitor populations in the spleen and bone marrow and differentially altered erythroid gene expression in these organs. In the bone marrow, the mRNA expression of erythroid differentiation genes (α-globin, β-globin, ALAS2 were inhibited by 50%, but mRNA levels of erythroid receptor (c-kit, EpoR and transcription factors (GATA1, GATA2, FOG1 were not affected by the infection. This suggests that infection has a negative effect on differentiation of erythroblasts. In the spleen, erythroid gene expression was enhanced by infection, indicating that the anemia activates a stress erythropoiesis response in the spleen. Analysis of cytokine mRNA levels in spleen and bone marrow found that IFN-γ mRNA is highly increased by L. donovani infection. Expression of the IFN-γ inducible cytokine, TNF-related apoptosis-inducing ligand (TRAIL, was also up-regulated. Since TRAIL induces erythroblasts apoptosis, apoptosis of bone marrow erythroblasts from infected hamsters was examined by flow cytometry. Percentage of erythroblasts that were apoptotic was significantly increased by L. donovani infection. Together, our results suggest that L. donovani infection inhibits erythropoiesis in the bone marrow by

  3. Bone marrow infiltration by multiple myeloma causes anemia by reversible disruption of erythropoiesis.

    Science.gov (United States)

    Bouchnita, Anass; Eymard, Nathalie; Moyo, Tamara K; Koury, Mark J; Volpert, Vitaly

    2016-06-01

    Multiple myeloma (MM) infiltrates bone marrow and causes anemia by disrupting erythropoiesis, but the effects of marrow infiltration on anemia are difficult to quantify. Marrow biopsies of newly diagnosed MM patients were analyzed before and after four 28-day cycles of nonerythrotoxic remission induction chemotherapy. Complete blood cell counts and serum paraprotein concentrations were measured at diagnosis and before each chemotherapy cycle. At diagnosis, marrow area infiltrated by myeloma correlated negatively with hemoglobin, erythrocytes, and marrow erythroid cells. After successful chemotherapy, patients with less than 30% myeloma infiltration at diagnosis had no change in these parameters, whereas patients with more than 30% myeloma infiltration at diagnosis increased all three parameters. Clinical data were used to develop mathematical models of the effects of myeloma infiltration on the marrow niches of terminal erythropoiesis, the erythroblastic islands (EBIs). A hybrid discrete-continuous model of erythropoiesis based on EBI structure/function was extended to sections of marrow containing multiple EBIs. In the model, myeloma cells can kill erythroid cells by physically destroying EBIs and by producing proapoptotic cytokines. Following chemotherapy, changes in serum paraproteins as measures of myeloma cells and changes in erythrocyte numbers as measures of marrow erythroid cells allowed modeling of myeloma cell death and erythroid cell recovery, respectively. Simulations of marrow infiltration by myeloma and treatment with nonerythrotoxic chemotherapy demonstrate that myeloma-mediated destruction and subsequent reestablishment of EBIs and expansion of erythroid cell populations in EBIs following chemotherapy provide explanations for anemia development and its therapy-mediated recovery in MM patients. Am. J. Hematol. 91:371-378, 2016. © 2016 Wiley Periodicals, Inc. PMID:26749142

  4. Critical requirement of VEGF-C in transition to fetal erythropoiesis.

    Science.gov (United States)

    Fang, Shentong; Nurmi, Harri; Heinolainen, Krista; Chen, Shuo; Salminen, Essi; Saharinen, Pipsa; Mikkola, Hanna K A; Alitalo, Kari

    2016-08-01

    Vascular endothelial growth factor C (VEGF-C) is a major driver of lymphangiogenesis in embryos and adults. Vegfc gene deletion in mouse embryos results in failure of lymphangiogenesis, fluid accumulation in tissues, and lethality. The VEGF-C receptors VEGFR3 and VEGFR2 are required for embryonic blood vessel formation. The related VEGF is essential for both blood vessel formation and embryonic hematopoiesis, whereas the possible involvement of VEGF-C in hematopoiesis is unknown. Here we unveil a novel hematopoietic function of VEGF-C in fetal erythropoiesis. Deletion of Vegfc in embryonic day 7.5 (E7.5) embryos in the C57BL6 mouse genetic background led to defective fetal erythropoiesis, characterized by anemia and lack of enucleated red blood cells in blood circulation. Macrophages and erythroid cells in the fetal liver (FL) were also decreased after midgestation because of decreased cell proliferation and increased apoptosis. However, the Lin(-)Sca-1(+)c-Kit(+) stem cell compartment in E14.5 FL was not affected by Vegfc deletion. VEGF-C loss did not disrupt the generation of primitive erythroid cells or erythro-myeloid progenitors (EMPs) in the yolk sac, but it decreased the expression of α4-integrin on EMPs and compromised EMP colonization of the FL. The distribution, maturation, and enucleation of primitive erythroblasts were also impaired by Vegfc deletion. In contrast, Vegfc deletion from E10.5 onward did not compromise definitive hematopoiesis in the liver, and Vegfc deletion in adult mice did not cause anemia. These results reveal an unexpected role for VEGF-C, a major lymphangiogenic growth factor, in the transition to FL erythropoiesis. PMID:27343251

  5. Control-relevant erythropoiesis modeling in end-stage renal disease.

    Science.gov (United States)

    Chait, Yossi; Horowitz, Joseph; Nichols, Brendan; Shrestha, Rajiv P; Hollot, C V; Germain, Michael J

    2014-03-01

    Anemia is prevalent in end-stage renal disease (ESRD). The discovery of recombinant human erythropoietin (rHuEPO) over 30 years ago has shifted the treatment of anemia for patients on dialysis from blood transfusions to rHuEPO therapy. Many anemia management protocols (AMPs) used by clinicians comprise a set of experience-based rules for weekly-to-monthly titration of rHuEPO doses based on hemoglobin (Hb) measurements. In order to facilitate the design of an AMP using model-based feedback control theory, we present a physiologically relevant erythropoiesis model and demonstrate its applicability using clinical data. PMID:24235247

  6. Stimulative effect of the fungal biocontrol agent Fusarium oxysporum f.sp. Striga on abundance of nitrifying prokaryotes in a maize rhizosphere

    Science.gov (United States)

    Musyoki, Mary; Enowashu, Esther; Zimmermann, Judith; Muema, Esther; Wainright, Henry; Vanlauwe, Bernard; Cadisch, Georg; Rasche, Frank

    2014-05-01

    The integration of resistant crop varieties and Fusarium oxysporum f.sp. strigae (Foxy-2) strains as biological control agent (BCA) has shown to be an effective control of the weed Striga hermonthica which is parasitic to several cereals (e.g., maize) cultivated in Sub-Saharan Africa. Most studies have examined the efficacy of the BCA and its interactions with host crops, while overlooking the interplay among key microorganisms in the soil nitrogen (N) cycle. Hence, we postulated that both Foxy-2 and Striga pose threats to the indigenous plant root-associated microbial communities involved in N cycling through direct or indirect competition for nutrients and that the application of high quality organic residues would compensate these effects. The primary objective of this study was thus to assess the potential impact of Foxy-2 on indigenous nitrifying prokaryotes in maize rhizosphere cultivated on two distinct soils (sandy Ferric Alisol versus clayey Humic Nitisol) obtained from Machanga and Embu, respectively, in central Kenya. These soils were treated with or without Foxy-2 and Striga; and in combination with high quality (i.e. CN ratio; 13, lignins, 8.9 % and polyphenols, 1.7 %) organic residues (i.e., Tithonia diversifolia) as N source. Using quantitative polymerase chain reaction (qPCR), we followed at three pre-defined sampling dates (14, 28 and 42 days after planting) the responses of ammonia-oxidizing archaea (AOA) and bacteria (AOB), total bacteria and archaea in four treatments of a rhizobox experiment: (i) Foxy-2 plus Striga (F+S), (ii) Striga only (C+S), (iii) Foxy-2 plus Striga plus Tithonia diversifolia residues (F+S+T), and (iv) a non-treated control (C). Overall, the treatment effects on soil microbial populations were, in comparison to the clayey Embu soil, more pronounced in the sandy Machanga soil. Contrary to our expectations, we observed a distinct stimulative, but no resource competition effect of Foxy-2 on the abundance of AOA, as well as

  7. Biomarkers of Hypochromia: The Contemporary Assessment of Iron Status and Erythropoiesis

    Directory of Open Access Journals (Sweden)

    Eloísa Urrechaga

    2013-01-01

    Full Text Available Iron status is the result of the balance between the rate of erythropoiesis and the amount of the iron stores. Direct consequence of an imbalance between the erythroid marrow iron requirements and the actual supply is a reduction of red cell hemoglobin content, which causes hypochromic mature red cells and reticulocytes. The diagnosis of iron deficiency is particularly challenging in patients with acute or chronic inflammatory conditions because most of the biochemical markers for iron metabolism (serum ferritin and transferrin are affected by acute phase reaction. For these reasons, interest has been generated in the use of erythrocyte and reticulocyte parameters, available on the modern hematology analyzers. Reported during blood analysis routinely performed on the instrument, these parameters can assist in early detection of clinical conditions (iron deficiency, absolute, or functional; ineffective erythropoiesis, including iron restricted or thalassemia, without additional cost. Technological progress has meant that in recent years modern analyzers report new parameters that provide further information from the traditional count. Nevertheless these new parameters are exclusive of each manufacturer, and they are patented. This is an update of these new laboratory test biomarkers of hypochromia reported by different manufactures, their meaning, and clinical utility on daily practice.

  8. TNF-related apoptosis-inducing ligand (TRAIL) as a negative regulator of normal human erythropoiesis.

    Science.gov (United States)

    Zamai, L; Secchiero, P; Pierpaoli, S; Bassini, A; Papa, S; Alnemri, E S; Guidotti, L; Vitale, M; Zauli, G

    2000-06-15

    The impact of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) on normal hematopoietic development was investigated using adult peripheral blood CD34(+) hematopoietic progenitor cells, induced to differentiate along the erythroid, megakaryocytic, granulocytic, and monocytic lineages by the addition of specific cytokine cocktails. TRAIL selectively reduced the number of erythroblasts, showing intermediate levels of glycophorin A (glycophorin A(interm)) surface expression, which appeared in liquid cultures supplemented with stem cell factor + interleukin 3 + erythropoietin at days 7-10. However, neither immature (day 4) glycophorin A(dim) erythroid cells nor mature (day 14) glycophorin A(bright) erythroblasts were sensitive to TRAIL-mediated apoptosis. Moreover, pre-exposure to TRAIL significantly decreased the number and size of erythroid colonies in semisolid assays. These adverse effects of TRAIL were selective for erythropoiesis, as TRAIL did not significantly influence the survival of cells differentiating along the megakaryocytic, granulocytic, or monocytic lineages. Furthermore, TRAIL was detected by Western blot analysis in lysates obtained from normal bone marrow mononuclear cells. These findings indicate that TRAIL acts in a lineage- and stage of differentiation-specific manner, as a negative regulator of normal erythropoiesis. (Blood. 2000;95:3716-3724) PMID:10845902

  9. MEK kinase 1 activity is required for definitive erythropoiesis in the mouse fetal liver

    DEFF Research Database (Denmark)

    Bonnesen, Barbara; Ørskov, Cathrine; Rasmussen, Susanne;

    2005-01-01

    Mitogen-activated protein kinase/extracellular signal to regulated kinase (MEK) kinase 1 (MEKK1) is a c-Jun N-terminal kinase (JNK) activating kinase known to be implicated in proinflammatory responses and cell motility. Using mice deficient for MEKK1 kinase activity (Mekk1(DeltaKD)) we show a role...... for MEKK1 in definitive mouse erythropoiesis. Although Mekk1(DeltaKD) mice are alive and fertile on a 129 x C57/BL6 background, the frequency of Mekk1(DeltaKD) embryos that develop past embryonic day (E) 14.5 is dramatically reduced when backcrossed into the C57/BL6 background. At E13.5, Mekk1(Delta......KD) embryos have normal morphology but are anemic due to failure of definitive erythropoiesis. When Mekk1(DeltaKD) fetal liver cells were transferred to lethally irradiated wild-type hosts, mature red blood cells were generated from the mutant cells, suggesting that MEKK1 functions in a non...

  10. Micronucleus test and erythropoiesis: effect of cobalt on the induction of micronuclei by mutagens.

    Science.gov (United States)

    Suzuki, Y; Shimizu, H; Nagae, Y; Fukumoto, M; Okonogi, H; Kadokura, M

    1993-01-01

    The micronucleus test is used widely as an in vivo short-term assay for potential carcinogens. In the present study, results of the micronucleus test were affected by cobalt dichloride pretreatment. Cobalt dichloride was used to induce erythropoietin, a growth factor for erythropoiesis. The increase in mutagen-induced micronucleus response following cobalt pretreatment, therefore, may have been due to a change in the rate of erythropoiesis. The greatest interaction between cobalt pretreatment and mutagen treatment for the induction of micronucleated polychromatic erythrocytes (MPCE) occurred when mice were injected with 1,1-dimethylhydrazine (DMH) 12-24 hr after pretreatment with cobalt dichloride and killed 30 hr later. Increased sensitivity of the micronucleus test was attributable to the administration of mutagen during the differentiation and multiplication of erythroblast, which is presumed to have been accelerated by pretreatment with cobalt dichloride. An increased induction of MPCE in the bone marrow by two chemicals--benzo(a)pyrene, 2-naphthylamine--was also observed following pretreatment with cobalt dichloride. PMID:8359151

  11. Simplification of an erythropoiesis model for design of anemia management protocols in end stage renal disease.

    Science.gov (United States)

    Nichols, B; Shrestha, R P; Horowitz, J; Hollot, C V; Germain, M J; Gaweda, A E; Chait, Y

    2011-01-01

    Many end stage renal disease (ESRD) patients suffer from anemia due to insufficient endogenous production of erythropoietin (EPO). The discovery of recombinant human EPO (rHuEPO) over 30 years ago has shifted the treatment of anemia for patients on dialysis from blood transfusions to rHuEPO therapy. Many anemia management protocols (AMPs) used by clinicians comprise a set of experience-based rules for weekly-to-monthly titration of rHuEPO doses based on hemoglobin (Hgb) measurements. In order to facilitate the design of an AMP based on formal control design methods, we present a physiologically-relevant erythropoiesis model, and show that its nonlinear dynamics can be approximated using a static nonlinearity, a step that greatly simplifies AMP design. We demonstrate applicability of our results using clinical data. PMID:22254256

  12. Inhibition of MAO-A and stimulation of behavioural activities in mice by the inactive prodrug form of the anti-influenza agent oseltamivir

    OpenAIRE

    Hiasa, Miki; Isoda, Yumiko; Kishimoto, Yasushi; Saitoh, Kenta; Kimura, Yasuaki; Kanai, Motomu; Shibasaki, Masakatsu; Hatakeyama, Dai; Kirino, Yutaka; Kuzuhara, Takashi

    2013-01-01

    Background and Purpose Oseltamivir is the most widely prescribed anti-influenza medication. However, in rare instances, it has been reported to stimulate behavioural activities in adolescents. The goal of this study was to determine the molecular mechanism responsible for these behavioural activities. Experimental Approach We performed an in vitro assay of MAO-A, the enzyme responsible for neurotransmitter degradation, using either the active form – oseltamivir carboxylate (OC) or the inactiv...

  13. Eighteen days of "living high, training low" stimulate erythropoiesis and enhance aerobic performance in elite middle-distance runners

    DEFF Research Database (Denmark)

    Brugniaux, Julien V; Schmitt, Laurent; Robach, Paul;

    2005-01-01

    to elucidate whether the mechanisms involved were only related to changes in oxygen-carrying capacity. Eleven elite middle-distance runners were tested before (Pre), at the end (Post1), and 15 days after the end (Post2) of an 18-day LHTL session. Hypoxic group (LHTL, n = 5) spent 14 h/day in hypoxia...

  14. Global analysis of induced transcription factors and cofactors identifies Tfdp2 as an essential coregulator during terminal erythropoiesis

    OpenAIRE

    Chen, Cynthia; Lodish, Harvey F.

    2014-01-01

    Key transcriptional regulators of terminal erythropoiesis, such as GATA1 and TAL1, have been well characterized, but transcription factors and cofactors and their expression modulations have not yet been explored on a global scale. Here we use global gene expression analysis to identify 28 transcription factors and 19 transcriptional cofactors induced during terminal erythroid differentiation and whose promoters are enriched for binding by GATA1 and TAL1. Utilizing protein-protein interaction...

  15. Sarcophine-Diol, a Skin Cancer Chemopreventive Agent, Inhibits Proliferation and Stimulates Apoptosis in Mouse Melanoma B16F10 Cell Line

    Directory of Open Access Journals (Sweden)

    Hesham Fahmy

    2011-12-01

    Full Text Available Sarcodiol (SD is a semi-synthetic derivative of sarcophine, a marine natural product. In our previous work, we reported the significant chemopreventive effects of SD against non-melanoma skin cancer both in vitro and in vivo mouse models. In this investigation, we extended this work to study the effect of sarcodiol on melanoma development, the more deadly form of skin cancer, using the mouse melanoma B16F10 cell line. In this study we report that SD inhibits the de novo DNA synthesis and enhances fragmentation of DNA. We also evaluated the antitumor effect of SD on melanoma cell viability using several biomarkers for cell proliferation and apoptosis. SD inhibits the expression levels of signal transducers and activators of transcription protein (STAT-3 and cyclin D1, an activator of cyclin-dependent kinase 4 (Cdk4. SD treatment also enhances cellular level of tumor suppressor protein 53 (p53 and stimulates cleavage of the nuclear poly (ADP-ribose polymerase (cleaved-PARP. SD also enhances cellular levels of cleaved Caspase-3, -8, -9 and stimulates enzymatic activities of Caspase-3, -8 and -9. These results, in addition to inhibition of cell viability, suggest that SD inhibits melanoma cell proliferation by arresting the cell-division cycle in a Go quiescent phase and activates programmed cell death (apoptosis via extrinsic and intrinsic pathways. Finally, these studies demonstrate that SD shows a very promising chemopreventive effect in melanoma B16F10 tumor cells.

  16. Sarcophine-diol, a skin cancer chemopreventive agent, inhibits proliferation and stimulates apoptosis in mouse melanoma B₁₆F₁₀ cell line.

    Science.gov (United States)

    Szymanski, Pawel T; Kuppast, Bhimanna; Ahmed, Safwat A; Khalifa, Sherief; Fahmy, Hesham

    2012-01-01

    Sarcodiol (SD) is a semi-synthetic derivative of sarcophine, a marine natural product. In our previous work, we reported the significant chemopreventive effects of SD against non-melanoma skin cancer both in vitro and in vivo mouse models. In this investigation, we extended this work to study the effect of sarcodiol on melanoma development, the more deadly form of skin cancer, using the mouse melanoma B₁₆F₁₀ cell line. In this study we report that SD inhibits the de novo DNA synthesis and enhances fragmentation of DNA. We also evaluated the antitumor effect of SD on melanoma cell viability using several biomarkers for cell proliferation and apoptosis. SD inhibits the expression levels of signal transducers and activators of transcription protein (STAT-3) and cyclin D1, an activator of cyclin-dependent kinase 4 (Cdk4). SD treatment also enhances cellular level of tumor suppressor protein 53 (p53) and stimulates cleavage of the nuclear poly (ADP-ribose) polymerase (cleaved-PARP). SD also enhances cellular levels of cleaved Caspase-3, -8, -9 and stimulates enzymatic activities of Caspase-3, -8 and -9. These results, in addition to inhibition of cell viability, suggest that SD inhibits melanoma cell proliferation by arresting the cell-division cycle in a Go quiescent phase and activates programmed cell death (apoptosis) via extrinsic and intrinsic pathways. Finally, these studies demonstrate that SD shows a very promising chemopreventive effect in melanoma B₁₆F₁₀ tumor cells. PMID:22363217

  17. Erythropoiesis: Correlations Between Iron Status Markers During Normal Pregnancy in Women with and without Iron Supplementation.

    Science.gov (United States)

    Byg, KELD-ERIK; Milman, NILS; Ole Agger, ANDERS

    2000-01-01

    The aim was to evaluate relationships between iron status markers (haemoglobin, erythrocyte indices, serum iron, serum transferrin, serum transferrin saturation, serum ferritin) in normal pregnancy. Iron status markers were measured at 4-week-intervals during pregnancy and postpartum in 120 healthy women; 62 had daily treatment with tablets containing 66 mg ferrous iron, 58 were treated with placebo. Placebo-treated: Ferritin displayed positive correlations with transferrin saturation during 2nd and 3rd trimester. There were positive correlations between ferritin, erythrocyte MCV and MCH during 2nd and 3rd trimester and postpartum. Prior to delivery and postpartum, ferritin demonstrated positive correlations with haemoglobin. Transferrin saturation showed positive correlations with MCV, MCH and MCHC during 2nd and 3rd trimester and postpartum. Transferrin saturation displayed positive correlations with haemoglobin prior to delivery and postpartum. Iron-treated: In general, there were no correlations between iron status markers. Positive correlations appeared postpartum between ferritin, transferrin saturation and MCHC but not with haemoglobin. Transferrin saturation showed a positive correlation with MCH postpartum, but not with haemoglobin. Conclusion: The patterns of relationships in placebo-treated women were consistent with iron deficient erythropoiesis. PMID:11399596

  18. Hepcidin-Dependent Regulation of Erythropoiesis during Anemia in a Teleost Fish, Dicentrarchus labrax

    Science.gov (United States)

    Caldas, Carolina; Ramos, Miguel F.; Rodrigues, Pedro N. S.

    2016-01-01

    Anemia is a common disorder, characterized by abnormally low levels of red blood cells or hemoglobin. The mechanisms of anemia development and response have been thoroughly studied in mammals, but little is known in other vertebrates, particularly teleost fish. In this study, different degrees of anemia were induced in healthy European sea bass specimens (Dicentrarchus labrax) and at pre-determined time points hematological parameters, liver iron content and the expression of genes involved in iron homeostasis and hematopoiesis, with particular attention on hepcidins, were evaluated. The experimental anemia prompted a decrease in hamp1 expression in all tested organs, in accordance to an increased need for iron absorption and mobilization, with slight increases in hamp2 in the kidney and intestine. The liver was clearly the major organ involved in iron homeostasis, decreasing its iron content and showing a gene expression profile consistent with an increased iron release and mobilization. Although both the spleen and head kidney are involved in erythropoiesis, the spleen was found to assume a more preponderant role in the recovery of erythrocyte levels. The intestine was also involved in the response to anemia, through the increase of iron transporting genes. Administration of Hamp1 or Hamp2 mature peptides showed that only Hamp1 affects hematological parameters and liver iron content. In conclusion, the molecular mechanisms of response to anemia present in sea bass are similar to the ones described for mammals, with these results indicating that the two hepcidin types from teleosts assume different roles during anemia. PMID:27100629

  19. Use of antimicrobial agents and granulocyte colony stimulating factors for febrile neutropenia in cancer patients in a tertiary care hospital in India

    Directory of Open Access Journals (Sweden)

    V Roy

    2010-01-01

    Full Text Available Background: Use of antimicrobials (AM and granulocyte colony stimulating factors (G-CSF affect the outcome and cost of treatment of febrile neutropenia (FN. There are no studies describing the AM utilization pattern or the use of G-CSF and cost incurred on them in cancer patients with FN from India. Materials and Methods: A study was conducted in a tertiary care, teaching hospital in New Delhi, India, with the objectives of describing the utilization pattern of AM and G-CSF in cancer patients with FN. The efficacy and costs of AM and G-CSF prescribed were also assessed. Results: A total of 211 patients with FN were enrolled in the study. A majority of 207 (98.1% were in the low-risk category. The average number of AM used per patient was 2.45 ± 0.02 and the AM exposure density was 1.19. All patients were administered five different combinations of AM regimens and G-CSF, irrespective of the risk category. No difference in the time to defervesence or in the recovery of ANC counts were observed with the different AM regimens. The average drug cost per febrile neutropenia episode (FNE was Rs 4694.45 ± 296.35 (113.95 ± 7.19$. G-CSF accounted for 76.14 - 97.58% of the total costs. Conclusion: Large variations in the pattern of AM prescribed with routine use of G-CSF, irrespective of the risk status, was observed. Guidelines for the rational and cost-effective use of AM and G-CSF in patients with FN needed to be prepared. This was especially important as treatment was given free of cost to all patients admitted in the government health facility.

  20. Radioprotective Agents

    Directory of Open Access Journals (Sweden)

    Ilker Kelle

    2008-01-01

    Full Text Available Since1949, a great deal of research has been carried out on the radioprotective activity of various chemical substances. Thiol compounds, compounds which contain –SH radical, different classes of pharmacological agents and other compounds such as vitamine C and WR-2721 have been shown to reduce mortality when administered prior to exposure to a lethal dose of radiation. Recently, honey bee venom as well as that of its components melittin and histamine have shown to be valuable in reduction of radiation-induced damage and also provide prophylactic alternative treatment for serious side effects related with radiotherapy. It has been suggested that the radioprotective activity of bee venom components is related with the stimulation of the hematopoetic system.

  1. Meis1 Is Required for Adult Mouse Erythropoiesis, Megakaryopoiesis and Hematopoietic Stem Cell Expansion.

    Science.gov (United States)

    Miller, Michelle Erin; Rosten, Patty; Lemieux, Madeleine E; Lai, Courteney; Humphries, R Keith

    2016-01-01

    Meis1 is recognized as an important transcriptional regulator in hematopoietic development and is strongly implicated in the pathogenesis of leukemia, both as a Hox transcription factor co-factor and independently. Despite the emerging recognition of Meis1's importance in the context of both normal and leukemic hematopoiesis, there is not yet a full understanding of Meis1's functions and the relevant pathways and genes mediating its functions. Recently, several conditional mouse models for Meis1 have been established. These models highlight a critical role for Meis1 in adult mouse hematopoietic stem cells (HSCs) and implicate reactive oxygen species (ROS) as a mediator of Meis1 function in this compartment. There are, however, several reported differences between these studies in terms of downstream progenitor populations impacted and effectors of function. In this study, we describe further characterization of a conditional knockout model based on mice carrying a loxP-flanked exon 8 of Meis1 which we crossed onto the inducible Cre localization/expression strains, B6;129-Gt(ROSA)26Sor(tm1(Cre/ERT)Nat)/J or B6.Cg-Tg(Mx1-Cre)1Cgn/J. Findings obtained from these two inducible Meis1 knockout models confirm and extend previous reports of the essential role of Meis1 in adult HSC maintenance and expansion and provide new evidence that highlights key roles of Meis1 in both megakaryopoiesis and erythropoiesis. Gene expression analyses point to a number of candidate genes involved in Meis1's role in hematopoiesis. Our data additionally support recent evidence of a role of Meis1 in ROS regulation. PMID:26986211

  2. Characterization of transcription factor networks involved in umbilical cord blood CD34+ stem cells-derived erythropoiesis.

    Directory of Open Access Journals (Sweden)

    Biaoru Li

    Full Text Available Fetal stem cells isolated from umbilical cord blood (UCB possess a great capacity for proliferation and differentiation and serve as a valuable model system to study gene regulation. Expanded knowledge of the molecular control of hemoglobin synthesis will provide a basis for rational design of therapies for β-hemoglobinopathies. Transcriptome data are available for erythroid progenitors derived from adult stem cells, however studies to define molecular mechanisms controlling globin gene regulation during fetal erythropoiesis are limited. Here, we utilize UCB-CD34+ stem cells induced to undergo erythroid differentiation to characterize the transcriptome and transcription factor networks (TFNs associated with the γ/β-globin switch during fetal erythropoiesis. UCB-CD34+ stem cells grown in the one-phase liquid culture system displayed a higher proliferative capacity than adult CD34+ stem cells. The γ/β-globin switch was observed after day 42 during fetal erythropoiesis in contrast to adult progenitors where the switch occurred around day 21. To gain insights into transcription factors involved in globin gene regulation, microarray analysis was performed on RNA isolated from UCB-CD34+ cell-derived erythroid progenitors harvested on day 21, 42, 49 and 56 using the HumanHT-12 Expression BeadChip. After data normalization, Gene Set Enrichment Analysis identified transcription factors (TFs with significant changes in expression during the γ/β-globin switch. Forty-five TFs were silenced by day 56 (Profile-1 and 30 TFs were activated by day 56 (Profile-2. Both GSEA datasets were analyzed using the MIMI Cytoscape platform, which discovered TFNs centered on KLF4 and GATA2 (Profile-1 and KLF1 and GATA1 for Profile-2 genes. Subsequent shRNA studies in KU812 leukemia cells and human erythroid progenitors generated from UCB-CD34+ cells supported a negative role of MAFB in γ-globin regulation. The characteristics of erythroblasts derived from UCB-CD34

  3. Erythroid overexpression of C/EBPgamma in transgenic mice affects gamma-globin expression and fetal liver erythropoiesis.

    OpenAIRE

    Zafarana, Gaetano; Rottier, Robbert; Grosveld, Frank; Philipsen, Sjaak

    2000-01-01

    textabstractThe CCAAT boxes of the beta-like globin genes interact with three proteins: NF-Y, GATA-1 and NFE-6. We demonstrate that NFE-6 contains C/EBPgamma, and address its role in globin gene regulation by erythroid overexpression of C/EBPgamma, and a dominant-negative form C/EBPgammaDeltaB, in mice. Elevated levels of C/EBPgamma, but not C/EBPgammaDeltaB, increase expression of the (fetal) gamma-globin relative to the (adult) beta-globin gene. Interestingly, fetal liver erythropoiesis is ...

  4. The c-Myb target gene neuromedin U functions as a novel cofactor during the early stages of erythropoiesis

    OpenAIRE

    Gambone, Julia E; Dusaban, Stephanie S.; Loperena, Roxana; Nakata, Yuji; Shetzline, Susan E.

    2011-01-01

    The requirement of c-Myb during erythropoiesis spurred an interest in identifying c-Myb target genes that are important for erythroid development. Here, we determined that the neuropeptide neuromedin U (NmU) is a c-Myb target gene. Silencing NmU, c-myb, or NmU's cognate receptor NMUR1 expression in human CD34+ cells impaired burst-forming unit-erythroid (BFU-E) and colony-forming unit-erythroid (CFU-E) formation compared with control. Exogenous addition of NmU peptide to NmU or c-myb siRNA-tr...

  5. Studies of intense granulocytic stimulation on the hemopoietic microenvironment of the bone marrow

    International Nuclear Information System (INIS)

    In an earlier study, we described the sustained suppression of both hemopoietic and stromal cell recovery in the irradiated field following large doses of partial-body x irradiation to mice. Surprisingly, we also noted long term changes in the marrow and spleen shielded from the irradiation. Our interest in these abscopal responses led us to clarify these effects. In Part I of this study, one hind leg of CF-1 female mice received 1000, 5000, or 10,000 rad of x irradiation. Studies were initiated in Part II to determine the effect of a variety of erythropoietic and granulocytopoietic stimuli on blood production and the stromal cells of the hemopoietic microenvironment. From these studies it was concluded that: (1) high doses of x irradiation to one leg of mice caused prolonged suppression of medullary erythropoiesis with splenic compensation to prevent anemia, (2) splennectomy, anemia, and hypoxia prevented the severe abscopal depression of medullary erythropoiesis, (3) transfusion or bleeding appropriately decreased or enhanced medullary and splenic erythropoiesis with no change in the growth of MSC, (4) endotoxin or turpentine caused granulocytic hyperplasia, anemia, and an inappropriately reduced erythroid response by the marrow, (5) the associated medullary erythroblastopenia in the presence of splenic erythroid hyperplasia and the suppressed growth of marrow stromal colonies suggested that intense granulocytopoietic stimulation caused a change in the marrow's hemopoietic microenvironment

  6. Data in support of transcriptional regulation and function of Fas-antisense long noncoding RNA during human erythropoiesis.

    Science.gov (United States)

    Villamizar, Olga; Chambers, Christopher B; Mo, Yin-Yuan; Torry, Donald S; Hofstrand, Reese; Riberdy, Janice M; Persons, Derek A; Wilber, Andrew

    2016-06-01

    This paper describes data related to a research article titled, "Fas-antisense long noncoding RNA is differentially expressed during maturation of human erythrocytes and confers resistance to Fas-mediated cell death" [1]. Long noncoding RNAs (lncRNAs) are increasingly appreciated for their capacity to regulate many steps of gene expression. While recent studies suggest that many lncRNAs are functional, the scope of their actions throughout human biology is largely undefined including human red blood cell development (erythropoiesis). Here we include expression data for 82 lncRNAs during early, intermediate and late stages of human erythropoiesis using a commercial qPCR Array. From these data, we identified lncRNA Fas-antisense 1 (Fas-AS1 or Saf) described in the research article. Also included are 5' untranslated sequences (UTR) for lncRNA Saf with transcription factor target sequences identified. Quantitative RT-PCR data demonstrate relative levels of critical erythroid transcription factors, GATA-1 and KLF1, in K562 human erythroleukemia cells and maturing erythroblasts derived from human CD34(+) cells. End point and quantitative RT-PCR data for cDNA prepared using random hexamers versus oligo(dT)18 revealed that lncRNA Saf is not effectively polyadenylated. Finally, we include flow cytometry histograms demonstrating Fas levels on maturing erythroblasts derived from human CD34(+) cells transduced using mock conditions or with lentivirus particles encoding for Saf. PMID:27141526

  7. JAK2 exon 12 mutant mice display isolated erythrocytosis and changes in iron metabolism favoring increased erythropoiesis.

    Science.gov (United States)

    Grisouard, Jean; Li, Sai; Kubovcakova, Lucia; Rao, Tata Nageswara; Meyer, Sara C; Lundberg, Pontus; Hao-Shen, Hui; Romanet, Vincent; Murakami, Masato; Radimerski, Thomas; Dirnhofer, Stephan; Skoda, Radek C

    2016-08-11

    Mutations in JAK2 exon 12 are frequently found in patients with polycythemia vera (PV) that do not carry a JAK2-V617F mutation. The majority of these patients display isolated erythrocytosis. We generated a mouse model that expresses JAK2-N542-E543del, the most frequent JAK2 exon 12 mutation found in PV patients. Mice expressing the human JAK2-N542-E543del (Ex12) showed a strong increase in red blood cell parameters but normal neutrophil and platelet counts, and reduced overall survival. Erythropoiesis was increased in the bone marrow and spleen, with normal megakaryopoiesis and absence of myelofibrosis in histopathology. Erythroid progenitors and precursors were increased in hematopoietic tissues, but the numbers of megakaryocytic precursors were unchanged. Phosphorylation Stat3 and Erk1/2 proteins were increased, and a trend toward increased phospho-Stat5 and phospho-Stat1 was noted. However, Stat1 knock out in Ex12 mice induced no changes in platelet or red cell parameters, indicating that Stat1 does not play a central role in mediating the effects of Ex12 signaling on megakaryopoiesis or erythropoiesis. Ex12 mice showed decreased expression of hepcidin and increased expression of transferrin receptor-1 and erythroferrone, suggesting that the strong erythroid phenotype in Ex12 mutant mice is favored by changes in iron metabolism that optimize iron availability to allow maximal production of red cells. PMID:27288519

  8. Global analysis of induced transcription factors and cofactors identifies Tfdp2 as an essential coregulator during terminal erythropoiesis.

    Science.gov (United States)

    Chen, Cynthia; Lodish, Harvey F

    2014-06-01

    Key transcriptional regulators of terminal erythropoiesis, such as GATA-binding factor 1 (GATA1) and T-cell acute lymphocytic leukemia protein 1 (TAL1), have been well characterized, but transcription factors and cofactors and their expression modulations have not yet been explored on a global scale. Here, we use global gene expression analysis to identify 28 transcription factors and 19 transcriptional cofactors induced during terminal erythroid differentiation whose promoters are enriched for binding by GATA1 and TAL1. Utilizing protein-protein interaction databases to identify cofactors for each transcription factor, we pinpoint several co-induced pairs, of which E2f2 and its cofactor transcription factor Dp-2 (Tfdp2) were the most highly induced. TFDP2 is a critical cofactor required for proper cell cycle control and gene expression. GATA1 and TAL1 are bound to the regulatory regions of Tfdp2 and upregulate its expression and knockdown of Tfdp2 results in significantly reduced rates of proliferation as well as reduced upregulation of many erythroid-important genes. Loss of Tfdp2 also globally inhibits the normal downregulation of many E2F2 target genes, including those that regulate the cell cycle, causing cells to accumulate in S phase and resulting in increased erythrocyte size. Our findings highlight the importance of TFDP2 in coupling the erythroid cell cycle with terminal differentiation and validate this study as a resource for future work on elucidating the role of diverse transcription factors and coregulators in erythropoiesis. PMID:24607859

  9. Study of the erythropoiesis activity of nano-encapsulated forms of erythropoietin

    Directory of Open Access Journals (Sweden)

    Zhanagul Khasenbekova

    2014-01-01

    Full Text Available Introduction: The recombinant human erythropoietin (rhEPO is used in the treatment of anemia. In order to improve its pharmacokinetic properties, nanoparticles of biodegradable polymers of natural or synthetic origin were used. The aim of this study was to investigate the effect of new nano-encapsulated forms of recombinant human erythropoietin for oral use on the erythropoiesis in the cyclophosphamide immunosuppression model. Material and methods: The CHOpE immortalized cells culture (a primary producer of rhEPO "Vector" in Russia was used. The following biodegradable polymers were chosen: 0.05% and 0.005% carbopol, 0.05% and 0.005% kollidon, and 0.05% and 0.005% pectin. Immunosuppression was obtained by a single dose of i.p. injection of cyclophosphamide (250 mg/kg in white mice (18-20 g. During the next 5 days, the nano-encapsulated erythropoietin (100 ED/mouse was administered orally to each mouse. After 5 and 10 days, the cell count of the number of blood reticulocytes and the myelogram of bone marrow were performed. The control group of mice received injections of Eprex. Results: On the 5th day of the experiment, the highest level of reticulocyte was observed in the samples of erythropoietin with kollidon (0.05% and pectin (0.005% nanoparticles. On the 10th day, the highest activity was observed in the samples of erythropoietin substance with pectin at 0.05% and 0.005% concentrations. The levels of reticulocytes in these groups reached 13.53% and 14.55%, respectively. The results of the myelogram during immunosuppression showed some activity of erythropoietin in conjunction with both concentrations of pectin when a two-fold increase in the number of erythroblasts was observed on the 5th day. High degrees of erythrokaryocytes in the state of mitosis were observed in the 0.05% pectin samples. Similar results were observed in equivalent groups of control animals on the 10th day of the experiment, which is compatible with the data on Eprex

  10. IN-VIVO EFFECTS OF INTERLEUKIN-11 AND STEM-CELL FACTOR IN COMBINATION WITH ERYTHROPOIETIN IN THE REGULATION OF ERYTHROPOIESIS

    NARCIS (Netherlands)

    DEHAAN, G; DONTJE, B; ENGEL, C; LOEFFLER, M; NIJHOF, W

    1995-01-01

    In this study we evaluated the in vivo effects of interleukin-11 (IL-11) and stem cell factor (SCF), in combination with erythropoietin (EPO) on murine erythropoiesis. Mice were treated for 7d with IL-11, SCF and EPO, each at three dose levels, In total, 27 different dose combinations were tested, I

  11. A key commitment step in erythropoiesis is synchronized with the cell cycle clock through mutual inhibition between PU.1 and S-phase progression

    NARCIS (Netherlands)

    R. Pop (Ramona); J.R. Shearstone (Jeffrey); Q. Shen (Qichang); Y. Liu (Ying); K. Hallstrom (Kelly); M. Koulnis (Miroslav); J.H. Gribnau (Joost); M. Socolovsky (Merav)

    2010-01-01

    textabstractHematopoietic progenitors undergo differentiation while navigating several cell division cycles, but it is unknown whether these two processes are coupled. We addressed this question by studying erythropoiesis in mouse fetal liver in vivo. We found that the initial upregulation of cell s

  12. Facteurs prédictifs de la réponse à la CERA chez les hémodialysés chroniques naïfs de traitement par agent stimulant l’érythropoïèse

    Science.gov (United States)

    Ezziani, Mariam; Najdi, Adil; Mikou, Souad; Hanin, Hakim; Arrayhani, Mohammed; Houssaini, Tarik Sqalli

    2015-01-01

    La correction et la stabilité du taux d'hémoglobine est un objectif majeur du traitement de l'anémie chez les hémodialysés chroniques. Toutefois, la cible d'hémoglobine > 11g/dl fixée par les recommandations demeure difficile à atteindre dans notre contexte. Le but de cette étude est d’évaluer la réponse au traitement par CERA (continuous erythropoietin receptor activator) chez une population d'hémodialysés chroniques naïfs de tout traitement par agent stimulant de l’érythropoïèse et étudier les différents facteurs associés à une mauvaise réponse au traitement. Il s'agit une étude prospective mono centrique faite au sein d'une population d’ hémodialysés chroniques. Ont été inclus les patients en hémodialyse depuis plus de 12 mois, naïfs de tout traitement par agent stimulant de l’érythropoïèse (ASE) et ayant un taux d'hémoglobine(Hb) 11g/dl. Sur 87 patients en hémodialyse périodique, 22 (25,3%) sont naïfs de tout traitement par ASE. Il s'agit de 13 hommes et 9 femmes avec un âge moyen de 46 ± 19 ans et une ancienneté en hémodialyse de 67 ± 59 mois. Le taux initial d'hémoglobine est de 7,8 ± 1,3 g/dl. Au bout de 4 mois de traitement régulier par la CERA, le taux final d'Hb est de 10,9 ± 2,1g/dl et 63,6% des patients ont atteint la cible d'Hb > 11g/dl. La dose moyenne de CERA à la fin de l’étude est de 0,89 ± 0,35 µg/kg/15j. L'analyse des facteurs prédictifs montre que la réponse finale dépend du taux d'Hb initial (p = 0,002). En effet, quand le taux d'Hb initial est > 8 g/dl, le taux de réponse est de 88% vs 46% lorsque le taux d'Hb 11 g/dl sans dépasser 13 g/dl [9, 10]. Cependant, le maintien d'un taux d'hémoglobine stable nécessite du temps, des ressources humaines et financières et exige des adaptations thérapeutiques fréquentes [11]. Le méthoxy polyéthylène glycol-époétine bêta, activateur continu du récepteur de l’érythropoïétine (C.E.R.A), est un nouvel ASE qui permet la

  13. Cardiovascular actions of drugs classed as stimulants.

    OpenAIRE

    Killian, Lindsey M

    2014-01-01

    The World Anti-Doping Agency prohibits and monitors the use of stimulants in sport. The effects of stimulants on enhancing performance in sport is uncertain. Stimulants have central and peripheral effects that can enhance mental or physical function. They are used therapeutically to treat a range of conditions most notable ADHD, depression and nasal decongestion. The present study looked at the peripheral sympathomimetic effects of stimulants on the cardiovascular system. The agents that were...

  14. Erythropoiesis- and Thrombopoiesis-Characterizing Parameters in Adenosine A(3) Receptor Knock-Out Mice

    Czech Academy of Sciences Publication Activity Database

    Hofer, Michal; Pospíšil, Milan; Dušek, L.; Hoferová, Zuzana; Weiterová, Lenka

    2013-01-01

    Roč. 62, č. 3 (2013), s. 305-311. ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP303/11/0128 Institutional support: RVO:68081707 Keywords : ELEVATING EXTRACELLULAR ADENOSINE * COLONY-STIMULATING FACTOR * HEMATOPOIETIC PROGENITOR CELLS Subject RIV: BO - Biophysics Impact factor: 1.487, year: 2013

  15. Erythropoietin or darbepoetin for patients with cancer

    OpenAIRE

    Tonia, Thomy; Mettler, Annette; Robert, Nadège; Schwarzer, Guido; Seidenfeld, Jerome; Weingart, Olaf; Hyde, Chris; Engert, Andreas; Bohlius, Julia

    2012-01-01

    Anaemia associated with cancer and cancer therapy is an important clinical factor in the treatment of malignant diseases. Therapeutic alternatives are recombinant human erythropoiesis stimulating agents (ESAs) and red blood cell transfusions.

  16. Infection-stimulated Anemia Results Primarily from Interferon Gamma-dependent, Signal Transducer and Activator of Transcription 1-independent Red Cell Loss

    Institute of Scientific and Technical Information of China (English)

    Zheng Wang; Dong-Xia Zhang; Qi Zhao

    2015-01-01

    Background:Although the onset of anemia during infectious disease is commonly correlated with production of inflammatory cytokines,the mechanisms by which cytokines induce anemia are poorly defined.This study focused on the mechanism research.Methods:Different types of mice were infected perorally with Toxoplasma gondii strain ME49.At the indicated times,samples from each mouse were harvested,processed,and analyzed individually.Blood samples were analyzed using a Coulter Counter and red blood cell (RBC) survival was measured by biotinylation.Levels of tumor necrosis factor-α (TNF-α),inducible nitric oxide synthase (iNOS),and inducible protein 10 (IP-10) mRNA in liver tissue were measured by real-time polymerase chain reaction.Results:T.gondii-infected mice exhibited anemia due to a decrease in both erythropoiesis and survival time of RBC in the circulation (P < 0.02).In addition,infection-stimulated anemia was associated with fecal occult,supporting previous literature that hemorrhage is a consequence of T.gondii infection in mice.Infection-induced anemia was abolished in interferon gamma (IFNγ) and IFNγ receptor deficient mice (P < 0.05) but was still evident in mice lacking TNF-α,iNOS,phagocyte NADPH oxidase or IP-10 (P < 0.02).Neither signal transducer and activator of transcription 1 (STAT1) deficient mice nor 129S6 controls exhibited decreased erythropoiesis,but rather suffered from an anemia resulting solely from increased loss of circulating RBC.Conclusions:Infection-stimulated decrease in erythropoiesis and losses of RBC have distinct mechanistic bases.These results show that during T.gondii infection,IFNγ is responsible for an anemia that results from both a decrease in erythropoiesis and a STAT1 independent loss of circulating RBC.

  17. Agent engineering

    CERN Document Server

    Liu, Jiming; Zhong, Ning; Wang, Patrick S P

    2001-01-01

    Agent engineering concerns the development of autonomous computational or physical entities capable of perceiving, reasoning, adapting, learning, cooperating and delegating in a dynamic environment. It is one of the most promising areas of research and development in information technology, computer science and engineering. This book addresses some of the key issues in agent engineering: What is meant by "autonomous agents"? How can we build agents with autonomy? What are the desirable capabilities of agents with respect to surviving (they will not die) and living (they will furthermore enjoy

  18. Rapid body mass loss affects erythropoiesis and hemolysis but does not impair aerobic performance in combat athletes.

    Science.gov (United States)

    Reljic, D; Feist, J; Jost, J; Kieser, M; Friedmann-Bette, B

    2016-05-01

    Rapid body mass loss (RBML) before competition was found to decrease hemoglobin mass (Hbmass ) in elite boxers. This study aimed to investigate the underlying mechanisms of this observation. Fourteen well-trained combat athletes who reduced body mass before competitions (weight loss group, WLG) and 14 combat athletes who did not practice RBML (control group, CON) were tested during an ordinary training period (t-1), 1-2 days before an official competition (after 5-7 days RBML in WLG, t-2), and after a post-competition period (t-3). In WLG, body mass (-5.5%, range: 2.9-6.8 kg) and Hbmass (-4.1%) were significantly (P < 0.001) reduced after RBML and were still decreased by 1.6% (P < 0.05) and 2.6% (P < 0.001) at t-3 compared with t-1. After RBML, erythropoietin, reticulocytes, haptoglobin, triiodothyronine (FT3 ), and free androgen index (FAI) were decreased compared with t-1 and t-3. An increase occurred in ferritin and bilirubin. Peak treadmill-running performance and VO2peak did not change significantly, but performance at 4-mmol lactate threshold was higher after RBML (P < 0.05). In CON, no significant changes were found in any parameter. Apparently, the significant decrease in Hbmass after RBML in combat athletes was caused by impaired erythropoiesis and increased hemolysis without significant impact on aerobic performance capacity. PMID:25916419

  19. Bioactive natural constituents from lemongrass tea and erythropoiesis boosting effects: potential use in prevention and treatment of anemia.

    Science.gov (United States)

    Ekpenyong, Christopher E; Daniel, Nyebuk E; Antai, Atim B

    2015-01-01

    This study assessed the effects of lemongrass (Cymbopogon citratus) tea on hematologic indices in human volunteers. One hundred five subjects (55 men and 50 women), aged 18 to 35 years, were randomly assigned to groups set to orally receive infusion prepared from 2, 4, or 8 g of C. citratus leaves once daily for 30 days. Assessment of hematologic indices (hemoglobin concentration [Hb], packed cell volume [PCV], red blood cell [RBC] count, mean cell Hb [MCH], mean cell volume [MCV], mean cell Hb concentration [MCHC], total white blood cell [WBC-total] and differentials, and platelets) were performed 1 day before (baseline), and at 10 (acute) and 30 days (subchronic phase) after the initiation of treatment. Results obtained on days 10 and 30 were compared with baseline values. Infusions prepared from C. citratus leaf powder, which tested positive for tannins, saponins, alkaloids, flavonoids, macro- and micronutrients, significantly increased PCV, Hb, and RBC (Pcitratus leaf infusion appears to exert an erythropoiesis boosting effect, likely due to some nutritional constituents and its antioxidant and pharmacologic properties. PMID:25162916

  20. Influence of Clinical Status and Parasite Load on Erythropoiesis and Leucopoiesis in Dogs Naturally Infected with Leishmania (Leishmania) chagasi

    Science.gov (United States)

    Trópia de Abreu, Raquel; Carvalho, Maria das Graças; Carneiro, Cláudia Martins; Giunchetti, Rodolfo Cordeiro; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; Coura-Vital, Wendel; Corrêa-Oliveira, Rodrigo; Reis, Alexandre Barbosa

    2011-01-01

    Background The bone marrow is considered to be an important storage of parasites in Leishmania-infected dogs, although little is known about cellular genesis in this organ during canine visceral leishmaniasis (CVL). Methodology/Principal Findings The aim of the present study was to evaluate changes in erythropoiesis and leucopoiesis in bone marrow aspirates from dogs naturally infected with Leishmania chagasi and presenting different clinical statuses and bone marrow parasite densities. The evolution of CVL from asymptomatic to symptomatic status was accompanied by increasing parasite density in the bone marrow. The impact of bone marrow parasite density on cellularity was similar in dogs at different clinical stages, with animals in the high parasite density group. Erythroid and eosinophilic hypoplasia, proliferation of neutrophilic precursor cells and significant increases in lymphocytes and plasma cell numbers were the major alterations observed. Differential bone marrow cell counts revealed increases in the myeloid:erythroid ratio associated to increased numbers of granulopoietic cells in the different clinical groups compared with non-infected dogs. Conclusions Analysis of the data obtained indicated that the assessment of bone marrow constitutes an additional and useful tool by which to elaborate a prognosis for CVL. PMID:21572995

  1. Antibiotic Agents

    Science.gov (United States)

    ... either as public health or as non-public health antimicrobial agents. What is the difference between bacteriostats, sanitizers, disinfectants ... bacteria, however, there is considerable controversy surrounding their health benefits. The ... producing agents (Table of Antibacterials) have been used for many ...

  2. Epigenetic Determinants of Erythropoiesis: Role of the Histone Methyltransferase SetD8 in Promoting Erythroid Cell Maturation and Survival.

    Science.gov (United States)

    DeVilbiss, Andrew W; Sanalkumar, Rajendran; Hall, Bryan D R; Katsumura, Koichi R; de Andrade, Isabela Fraga; Bresnick, Emery H

    2015-06-01

    Erythropoiesis, in which committed progenitor cells generate millions of erythrocytes daily, involves dramatic changes in the chromatin structure and transcriptome of erythroblasts, prior to their enucleation. While the involvement of the master-regulatory transcription factors GATA binding protein 1 (GATA-1) and GATA-2 in this process is established, the mechanistic contributions of many chromatin-modifying/remodeling enzymes in red cell biology remain enigmatic. We demonstrated that SetD8, a histone methyltransferase that catalyzes monomethylation of histone H4 at lysine 20 (H4K20me1), is a context-dependent GATA-1 corepressor in erythroid cells. To determine whether SetD8 controls erythroid maturation and/or function, we used a small hairpin RNA (shRNA)-based loss-of-function strategy in a primary murine erythroblast culture system. In this system, SetD8 promoted erythroblast maturation and survival, and this did not involve upregulation of the established regulator of erythroblast survival Bcl-x(L). SetD8 catalyzed H4K20me1 at a critical Gata2 cis element and restricted occupancy by an enhancer of Gata2 transcription, Scl/TAL1, thereby repressing Gata2 transcription. Elevating GATA-2 levels in erythroid precursors yielded a maturation block comparable to that induced by SetD8 downregulation. As lowering GATA-2 expression in the context of SetD8 knockdown did not rescue erythroid maturation, we propose that SetD8 regulation of erythroid maturation involves multiple target genes. These results establish SetD8 as a determinant of erythroid cell maturation and provide a framework for understanding how a broadly expressed histone-modifying enzyme mediates cell-type-specific GATA factor function. PMID:25855754

  3. Quantification of ineffective erythropoiesis in megaloblastic anaemia by determination of endogenous production of 14CO after administration of glycine-2-14C

    International Nuclear Information System (INIS)

    The determination of the early peak of 14CO production that results from haem turnover after administration of glycine-2-14C was studied in patients with pernicious anaemia. The accuracy of this technique in measuring ineffective erythropoiesis was assessed by comparison with other measurements of the severity of the disease. 6 patients were studied before specific treatment and 2 of these also after treatment. The endogenous production of 14CO was calculated from determinations of the production of CO by a rebreathing technique and of the specific activity of CO washed out from the body CO store by oxygen breathing. The early labelled peak was increased 7-39 times compared to that in healthy control subjects and represented 35-86% of the total production of 14CO as compared to 13% in controls. The early labelled peak was significantly correlated to the Hb concentration, mean red cell volume and endogenous production of CO. 2 patients, twice examined, showed a moderately increased early labelled peak also after specific treatment. This was attributed to persistence of some ineffective erythropoiesis in 1 patient and possibly increased hepatic haem turnover in the other. The magnitude of the early labelled peak and the maximal activity of 14CO found in the samples of CO collected from the body CO store were significantly correlated. In conclusion, with the present method the early peak of 14CO reflected the ineffective erythropoiesis in patients with pernicious anaemia. The early labelled peak could be predicted from the maximal activity of 14CO found in the samples of CO washed out from the body CO store. (author)

  4. Impaired In Vitro Erythropoiesis following Deletion of the Scl (Tal1) +40 Enhancer Is Largely Compensated for In Vivo despite a Significant Reduction in Expression

    OpenAIRE

    Ferreira, Rita; Spensberger, Dominik; Silber, Yvonne; Dimond, Andrew; Li, Juan; Green, Anthony R.; Göttgens, Berthold

    2013-01-01

    The Scl (Tal1) gene encodes a helix-loop-helix transcription factor essential for hematopoietic stem cell and erythroid development. The Scl +40 enhancer is situated downstream of Map17, the 3′ flanking gene of Scl, and is active in transgenic mice during primitive and definitive erythropoiesis. To analyze the in vivo function of the Scl +40 enhancer within the Scl/Map17 transcriptional domain, we deleted this element in the germ line. SclΔ40/Δ40 mice were viable with reduced numbers of eryth...

  5. Strong iron demand during hypoxia-induced erythropoiesis is associated with down-regulation of iron-related proteins and myoglobin in human skeletal muscle

    DEFF Research Database (Denmark)

    Robach, Paul; Cairo, Gaetano; Gelfi, Cecilia;

    2007-01-01

    , mobilizes body iron, and increases hemoglobin concentration. However, contrary to our hypothesis that muscle iron proteins and myoglobin would also be up-regulated during HA, this study shows that HA lowers myoglobin expression by 35% and down-regulates iron-related proteins in skeletal muscle, as evidenced...... increase. This study gives new insights into the changes in iron content and iron-oxygen interactions during enhanced erythropoiesis by simultaneously analyzing blood and muscle samples in humans exposed to 7 to 9 days of high altitude hypoxia (HA). HA up-regulates iron acquisition by erythroid cells...

  6. Agent, autonomous

    OpenAIRE

    Luciani, Annie

    2007-01-01

    The expression autonomous agents, widely used in virtual reality, computer graphics, artificial intelligence and artificial life, corresponds to the simulation of autonomous creatures, virtual (i.e. totally computed by a program), or embodied in a physical envelope, as done in autonomous robots.

  7. Heme transport and erythropoiesis

    OpenAIRE

    Yuan, Xiaojing; Fleming, Mark D.; Hamza, Iqbal

    2013-01-01

    In humans, systemic heme homeostasis is achieved via coordinated regulation of heme synthesis, transport and degradation. Although the heme biosynthesis and degradation pathways have been well characterized, the pathways for heme trafficking and incorporation into hemoproteins remains poorly understood. In the past few years, researchers have exploited genetic, cellular and biochemical tools, to identify heme transporters and, in the process, reveal unexpected functions for this elusive group...

  8. Antifungal agents.

    Science.gov (United States)

    Ryder, N S

    1999-12-01

    At this year's ICAAC Meeting, new data on approximately 20 different antifungal agents were presented, while no new agents were disclosed. Drugs in late development include the triazoles, voriconazole (Pfizer Ltd) and Sch-56592 (Schering-Plough Corp), and the echinocandins, caspofungin (Merck & Co Inc) and FK-463 (Fujisawa Pharmaceutical Co Ltd). In contrast to previous years, presentations on these and earlier developmental compounds were relatively modest in scope, with few significant new data. Little new information appeared on the most recent novel class of agents, the sordarins (Glaxo Wellcome plc). Early clinical results were presented for FK-463, showing acceptable tolerability and dose-dependent efficacy in AIDS-associated esophageal candidiasis. A new liposomal formulation of nystatin (Nyotran; Aronex Pharmaceuticals Inc) was shown to be equivalent to conventional amphotericin B in empiric therapy of presumed fungal infection in neutropenic patients, but with reduced toxicity. Intravenous itraconazole (Janssen Pharmaceutica NV) was an effective prophylactic therapy in invasive pulmonary aspergillosis, while oral itraconazole was discussed as a treatment for fungal infection in heart and liver transplant patients. The allylamine compound, terbinafine (Novartis AG), showed good clinical efficacy against fungal mycetoma, a serious tropical infection. A major highlight was the first presentation of inhibitors of fungal efflux pumps as a strategy for overcoming resistance. MC-510027 (milbemycin alpha-9; Microcide Pharmaceuticals Inc) and its derivatives, potentiated the antifungal activity of triazoles and terbinafine in a number of Candida spp. Another pump inhibitor, MC-005172 (Microcide Pharmaceuticals Inc) showed in vivo potentiation of fluconazole in a mouse kidney infection model. Microcide Pharmaceuticals Inc also presented inhibitors of bacterial efflux pumps. PMID:16113946

  9. Trading Agents

    CERN Document Server

    Wellman, Michael

    2011-01-01

    Automated trading in electronic markets is one of the most common and consequential applications of autonomous software agents. Design of effective trading strategies requires thorough understanding of how market mechanisms operate, and appreciation of strategic issues that commonly manifest in trading scenarios. Drawing on research in auction theory and artificial intelligence, this book presents core principles of strategic reasoning that apply to market situations. The author illustrates trading strategy choices through examples of concrete market environments, such as eBay, as well as abst

  10. MORBIDITY AGENTS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Shrivastava Neelesh

    2011-09-01

    Full Text Available This paper discuss on clinical representation of morbid jealousy which often termed delusional jealousy or ‘Othello Syndrome’ is a psychiatric condition where a lover believes against all reason and their beloved is being sexually unfaithful. Patients will be preoccupied with their partner’s perceived lack of sexual fidelity and will often behave in an unacceptable or extreme way as they endeavor to prove their ideas. Misuse of any psychomotor is an important association cause morbidity jealousy agents, like CNS stimulants that release the catecholamine, particularly dopamine, from pre synaptic terminals substance should be treated as a priority. Where higher levels of violence are reported Sildenafil may be useful as a diagnostic as well as therapeutic test in such cases .Many studies have shown an association between high alcohol consumption and developing morbid jealousy. Amphetamine-induced psychosis has been extensively studied because of its close resemblance to schizophrenia.

  11. Once-Monthly Continuous Erythropoietin Receptor Activator (C.E.R.A.) in Patients with Hemodialysis-Dependent Chronic Kidney Disease: Pooled Data from Phase III Trials

    OpenAIRE

    Locatelli, Francesco; Choukroun, Gabriel; Truman, Matt; Wiggenhauser, Alfons; Fliser, Danilo

    2016-01-01

    Introduction Erythropoiesis-stimulating agents and iron are commonly used in patients with chronic kidney disease with the aim of correcting anemia and maintaining stable hemoglobin levels. We analyzed pooled data from 13 studies with similar designs included in the Umbrella Continuous Erythropoietin Receptor Activator (C.E.R.A.) program to investigate the effects of continuous erythropoiesis receptor activator in clinically relevant subgroups of patients with chronic kidney disease and to de...

  12. An agent framework for dynamic agent retraining: Agent academy

    OpenAIRE

    Mitkas, P.; A. Symeonidis; Kechagias, D.; Athanasiadis, I.N.; Laleci, G.; KURT, G.; Kabak, Y.; Acar, A.; Dogac, A.

    2004-01-01

    Agent Academy (AA) aims to develop a multi-agent society that can train new agents for specific or general tasks, while constantly retraining existing agents in a recursive mode. The system is based on collecting information both from the environment and the behaviors of the acting agents and their related successes/failures to generate a body of data, stored in the Agent Use Repository, which is mined by the Data Miner module, in order to generate useful knowledge about the application domai...

  13. Acute and chronic elevation of erythropoietin in the brain improves exercise performance in mice without inducing erythropoiesis

    OpenAIRE

    Schuler, Beat; Vogel, Johannes; Grenacher, Beat; Jacobs, Robert A.; Arras, Margarete; Gassmann, Max

    2012-01-01

    Application of recombinant human erythropoietin (rhEpo) improves exercise capacity by stimulating red blood cell production that, in turn, enhances oxygen delivery and utilization. Apart from this, when applied at high doses, rhEpo crosses the blood-brain barrier, triggering protective neuronal effects. Here we show a fundamental new role by which the presence of Epo in the brain augments exercise performance without altering red blood cell production. Two different animal models, the transge...

  14. Ovarian stimulation in patients with breast cancer.

    Science.gov (United States)

    Muñoz, Elkin; González, Naira; Muñoz, Luis; Aguilar, Jesús; Velasco, Juan A García

    2015-01-01

    Breast cancer is the most prevalent malignancy among women under 50. Improvements in diagnosis and treatment have yielded an important decrease in mortality in the last 20 years. In many cases, chemotherapy and radiotherapy develop side effects on the reproductive function. Therefore, before the anti-cancer treatment impairs fertility, clinicians should offer some techniques for fertility preservation for women planning motherhood in the future. In order to obtain more available oocytes for IVF, the ovary must be stimulated. New protocols which prevent exposure to increased estrogen during gonadotropin stimulation, measurements to avoid the delay in starting anti-cancer treatment or the outcome of ovarian stimulation have been addressed in this review. There is no evidence of association between ovarian stimulation and breast cancer. It seems that there are more relevant other confluent factors than ovarian stimulation. Factors that can modify the risk of breast cancer include: parity, age at full-term birth, age of menarche, and family history. There is an association between breast cancer and exogenous estrogen. Therefore, specific protocols to stimulate patients with breast cancer include anti-estrogen agents such as letrozole. By using letrozole plus recombinant follicular stimulating hormone, patients develop a multifollicular growth with only a mild increase in estradiol serum levels. Controlled ovarian stimulation (COS) takes around 10 days, and we discuss new strategies to start COS as soon as possible. Protocols starting during the luteal phase or after inducing the menses currently prevent a delay in starting ovarian stimulation. Patients with breast cancer have a poorer response to COS compared with patients without cancer who are stimulated with conventional protocols of gonadotropins. Although many centres offer fertility preservation and many patients undergo ovarian stimulation, there are not enough studies to evaluate the recurrence, breast cancer

  15. Interactions of ionic and nonionic contrast agents with thrombolytic agents

    International Nuclear Information System (INIS)

    Both the ionic and nonionic intravascular contrast media have been used before and after the administration of thrombolytic agents to evaluate clot lysis during angioplasty and the treatment of myocardial infarction. In experimental animal models, the authors found that the clot lytic efficacy of streptokinase, streptokinase-plasminogen complex, and tissue plasminogen activator (t-PA) is markedly augmented if these agents are administered within 1 hour after the angiographic producers. Furthermore, contrast agents injected after the administration of t-Pa exhibit a synergistic action. In stimulated models administration of one ionic contrast medium (Angiovist, Berlex, Wayne, NJ) and two nonionic contrast agents (Isovue-370, Squibb Diagnostics, New Brunswick, NJ; Omnipaque-350, Winthrop, NY) 15 minutes before the administration of t-PA resulted in marked enhancement of the lytic activity. Although the mechanism of this interaction is unknown at this time, it should be taken into consideration in the treatment of patients with myocardial infarction, in whom contrast agents are continually used to evaluate the therapeutic lysis. Furthermore, this interaction may be partly related to the therapeutic efficacy and/or hemorrhagic actions observed

  16. Mechanism of anaemia in rheumatoid arthritis: demonstration of raised interleukin 1 beta concentrations in anaemic patients and of interleukin 1 mediated suppression of normal erythropoiesis and proliferation of human erythroleukaemia (HEL) cells in vitro.

    OpenAIRE

    Maury, C P; Andersson, L C; Teppo, A M; Partanen, S. (Sari); Juvonen, E

    1988-01-01

    The pathogenesis of the anaemia associated with rheumatoid disease is unclear. It has previously been shown that the degree of the anaemia correlates with the severity of the inflammatory disease and that serum from patients with arthritis inhibits erythropoiesis. This study was designed to examine whether interleukin 1 could be a mediator of the anaemia in rheumatoid arthritis. Radioimmunoassay of interleukin 1 beta in serum showed that patients with rheumatoid arthritis and associated anaem...

  17. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank

    2014-01-01

    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  18. Transcranial Electric Field Stimulation

    OpenAIRE

    Arfaee, Arash

    2015-01-01

    Nervous stimulation with electric methods not only has a long history in the treatment of many conditions but also in the last two decades has been used increasingly as a powerful functional brain mapping tool alongside other imaging techniques. This technology has been used to record the stimulation-evoked activity of the stimulated location. This research describes work surrounding a novel technique for brain and nervous stimulation using the electric field as the medium; particularly tra...

  19. Stimulation of biological activities using low radiation doses

    International Nuclear Information System (INIS)

    Hormesis is the excitation, or stimulation, by low doses of any agent in any system; high doses inhibit but low doses stimulate. Don Luckey from the University of Florida identified the phenomenon of radiation hormesis, in 1982. After nearly ten years of data surveys and animal tests in many universities to examine the truth about radiation hormesis, we realized the scientific significance of the stimulating effects caused by low levels of radiation exposure. Stimulation with Ionizing radiation presented evidence of increased vigor in plants, bacteria, invertebrates and vertebrates. Most physiologic reactions in living cells are stimulated by low doses of ionizing radiation. This stimulating effect includes enzyme induction, photosynthesis, respiration and growth. Radiation stimulation to the immune system decreases infection and premature death in radiation exposed individuals. (author)

  20. Agent Chameleons: Virtual Agents Real Intelligence

    OpenAIRE

    O'Hare, Gregory; Duffy, Brian; Schoen-Phelan, Bianca; Martin, Alan; Bradley, John

    2003-01-01

    Agent Chameleons provides virtual agents powered by real intelligence, delivering next generation autonomic entities that can seamlessly migrate, mutate and evolve on their journey between and within physical and digital information spaces.

  1. Intrinsic defects in erythroid cells from familial hemophagocytic lymphohistiocytosis type 5 patients identify a role for STXBP2/Munc18-2 in erythropoiesis and phospholipid scrambling.

    Science.gov (United States)

    Kostova, Elena B; Beuger, Boukje M; Veldthuis, Martijn; van der Werff Ten Bosch, Jutte; Kühnle, Ingrid; van den Akker, Emile; van den Berg, Timo K; van Zwieten, Rob; van Bruggen, Robin

    2015-12-01

    Familial hemophagocytic lymphohistiocytosis type 5 (FHL-5) is a rare genetic disorder caused by mutations in STXBP2/Munc18-2. Munc18-2 plays a role in the degranulation machinery of natural killer cells and cytotoxic T lymphocytes. Mutations in STXBP2/Munc18-2 lead to impaired killing of target cells by natural killer cells and cytotoxic T lymphocytes, which in turn results in elevated levels of the inflammatory cytokine interferon γ, macrophage activation, and hemophagocytosis. Even though patients with FHL-5 present with anemia and hemolysis, no link between the disease and the erythroid lineage has been established. Here we report that red blood cells express Munc18-2 and that erythroid cells from patients with FHL-5 exhibit intrinsic defects caused by STXBP2/Munc18-2 mutations. Red blood cells from patients with FHL-5 expose less phosphatidylserine on their surface upon Ca(2+) ionophore ionomycin treatment. Furthermore, cultured erythroblasts from patients with FHL-5 display defective erythropoiesis characterized by decreased CD235a expression and aberrant cell morphology. PMID:26320718

  2. Injectable agents affecting subcutaneous fats.

    Science.gov (United States)

    Chen, David Lk; Cohen, Joel L; Green, Jeremy B

    2015-09-01

    Mesotherapy is an intradermal or subcutaneous injection of therapeutic agents to induce local effects, and was pioneered in Europe during the 1950s. For the past 2 decades, there has been significant interest in the use of mesotherapy for minimally invasive local fat contouring. Based on the theorized lipolytic effects of the agent phosphatidylcholine, initial attempts involved its injection into subcutaneous tissue. With further studies, however, it became apparent that the activity attributed to phosphatidylcholine mesotherapy was due to the adipolytic effects of deoxycholate, a detergent used to solubilize phosphatidylcholine. Since then, clinical trials have surfaced that demonstrate the efficacy of a proprietary formulation of deoxycholate for local fat contouring. Current trials on mesotherapy with salmeterol, a b-adrenergic agonist and lipolysis stimulator, are underway-with promising preliminary results as well. PMID:26566569

  3. Performance-enhancing drugs: understanding the risks.

    Science.gov (United States)

    Hatton, Caroline K; Green, Gary A; Ambrose, Peter J

    2014-11-01

    To help clinicians understand the risks associated with performance-enhancing drugs, this overview covers prohibited lists of substances and methods, therapeutic use exemptions, the legitimate indications and adverse effects, including for megadose and polypharmacy doping of stimulants, anabolic steroids, erythropoiesis-stimulating agents, and growth hormone and ways in which physicians or patients risk committing anti-doping rule violations inadvertently. PMID:25442165

  4. Deep Brain Stimulation

    OpenAIRE

    Perlmutter, Joel. S.; Mink, Jonathan W.

    2006-01-01

    Deep brain stimulation (DBS) has provided remarkable benefits for people with a variety of neurologic conditions. Stimulation of the ventral intermediate nucleus of the thalamus can dramatically relieve tremor associated with essential tremor or Parkinson disease (PD). Similarly, stimulation of the subthalamic nucleus or the internal segment of the globus pallidus can substantially reduce bradykinesia, rigidity, tremor, and gait difficulties in people with PD. Multiple groups are attempting t...

  5. Stimulant Use Disorders.

    Science.gov (United States)

    Park, Taryn M; Haning, William F

    2016-07-01

    Compared with other illicit substances, stimulants are not commonly used by adolescents; however, they represent a serious concern regarding substance use among youths. This article uses methamphetamine as a model for stimulant use in adolescents; cocaine and prescription stimulants are also mentioned. Methamphetamine use among adolescents and young adults is a serious health concern with potentially long-term physical, cognitive, and psychiatric consequences. Brain development and the effects of misusing stimulants align such that usage in adolescents can more dangerous than during adulthood. It seems helpful to keep in mind the differences between adolescents and young adults when implementing interventions. PMID:27338967

  6. Artificial intelligence for optimal anemia management in end-stage renal disease.

    Science.gov (United States)

    Brier, Michael E; Gaweda, Adam E

    2016-08-01

    Computational intelligence for the prediction of hemoglobin to guide the selection of erythropoiesis-stimulating agent dose results in improved anemia management. The models used for the prediction result from the use of individual patient data and help to increase the number of hemoglobin observations within the target range. The benefits of using these modeling techniques appear to be a decrease in erythropoiesis-stimulating agent use and a decrease in the number of transfusions. This study confirms the results of previous smaller studies and suggests that additional beneficial results may be achieved. PMID:27418093

  7. Bi-functional prodrugs of 5-aminolevulinic acid and butyric acid increase erythropoiesis in anemic mice in an erythropoietin-independent manner.

    Science.gov (United States)

    Rephaeli, Ada; Tarasenko, Nataly; Fibach, Eitan; Rozic, Gabriela; Lubin, Ido; Lipovetsky, Julia; Furman, Svetlana; Malik, Zvi; Nudelman, Abraham

    2016-08-25

    Anemia is a major cause of morbidity and mortality worldwide resulting from a wide variety of pathological conditions. In severe cases it is treated by blood transfusions or injection of erythroid stimulating agents, e.g., erythropoietin (Epo), which can be associated with serious adverse effects. Therefore, there is a need to develop new treatment modalities. We recently reported that treatment of erythroleukemic cells with the novel the bi-functional prodrugs of 5-aminolevulinic acid (ALA) and butyric acid (BA), AN233 and AN908, enhanced hemoglobin (Hb) synthesis to a substantially higher level than did ALA and BA individually or their mixture. Herein, we describe that these prodrugs when given orally to mice induced histone deacetylase inhibition in the kidneys, bone marrow and spleen, thus, indicating good penetrability to the tissues. In mice where anemia was chemically induced, treatment with the prodrugs increased the Hb, the number of red blood cells (RBCs) and the percentage of reticulocytes to normal levels. The prodrugs had no adverse effects even after repeated treatment at 100-200mg/kg for 50days. The lack of increased levels of Epo in the blood of mice that were treated with the prodrugs suggests that AN233 and AN908 affected the Hb and RBC levels in an Epo-independent manner. Taken together with our previous studies, we propose that the prodrugs increase globin expression by BA inhibition of histone deacetylase and elevation heme synthesis by ALA. These results support an Epo-independent approach for treating anemia with these prodrugs. PMID:27283485

  8. Stimulated Resonant Radiation

    CERN Document Server

    Clerici, M; Rubino, E; Moss, D; Couairon, A; Légaré, F; Morandotti, R; Faccio, D

    2014-01-01

    Resonant radiation (RR) is emitted by solitons propagating in a waveguide or by filamenting pulses in bulk media. Recent studies have highlighted the possibility to stimulate RR also in weaker pulses that co-propogate with a pump pulse. We numerically and experimentally demonstrate that RR radiation can be stimulated employing a THz seed co-propagating in diamond with an intense 800 nm pulse. This way we predict and observe the stimulated emission of RR at 425 nm, thus bridging a spectral gap of more than six octaves and allowing the detection of THz pulses by means of a silicon-based device.

  9. Growth hormone stimulation test

    Science.gov (United States)

    The growth hormone (GH) stimulation test measures the ability of the body to produce GH. ... killing medicine (antiseptic). The first sample is drawn early in the morning. Medicine is given through the ...

  10. Geothermal Well Stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D. A.; Morris, C. W.; Sinclair, A. R.; Hanold, R. J.; Vetter, O. J.

    1981-03-01

    The stimulation of geothermal wells presents some new and challenging problems. Formation temperatures in the 300-600 F range can be expected. The behavior of stimulation fluids, frac proppants, and equipment at these temperatures in a hostile brine environment must be carefully evaluated before performance expectations can be determined. In order to avoid possible damage to the producing horizon of the formation, high temperature chemical compatibility between the in situ materials and the stimulation materials must be verified. Perhaps most significant of all, in geothermal wells the required techniques must be capable of bringing about the production of very large amounts of fluid. This necessity for high flow rates represents a significant departure from conventional petroleum well stimulation and demands the creation of very high near-wellbore permeability and/or fractures with very high flow conductivity.

  11. AgentChess : An Agent Chess Approach

    OpenAIRE

    Fransson, Henric

    2003-01-01

    The game of chess has many times been discussed and used for test purpose by science departments of Artificial Intelligence (AI). Although the technique of agent and as well multi-agent systems is quite old, the use of these offspring of AI within chess is limited. This report describes the project performed applying the use of agents to a chess program. To measure the performance of the logic has tests between the developed program main parts been performed. Further tests against a tradition...

  12. Coagulation, red cell aggregation, and the nonionic contrast agents

    International Nuclear Information System (INIS)

    Interest in the interactions between iodinated contrast agents and blood has been renewed recently following reports by Robertson in the United States of clots forming in blood-contaminated nonionic contrast agents in syringes, and by Raininko and Ylinen in Sweden of disordered red cell aggregation seemingly stimulated by nonionic contrast agents. These phenomena have been described and explained, and their significance for clinical angiography have been discussed. It has been suggested by a number of commentators that some contrast agents may be actively prothrombotic

  13. Stimulated Thomson scattering

    International Nuclear Information System (INIS)

    The theory of stimulated Thomson scattering is investigated both quantum mechanically and classically. In the interaction of a collisionless plasma with two electromagnetic waves, both with frequencies well above the plasma frequency, energy is transferred from the high-frequency wave to the low-frequency wave via stimulated Thomson scattering. This process is mediated by the nonlinear interaction of the plasma electrons with a beat wave at the difference frequency between the two waves; this beat frequency must be well above the plasma frequency. The gain coefficient for stimulated Thomson scattering is calculated both quantum mechanically and classically, and identical results are obtained. The classical calculation also yields the first nonlinear term in the index of refraction due to stimulated Thomson scattering, as well as the details of the saturation of the gain and the index of refraction. The authors present explicit formulas for the gain coefficient and the index of refraction, in the unsaturated limit, for both very cold and very hot plasmas. The calculations indicate that it should be possible to detect stimulated Thomson scattering experimentally by means of polarization enhancement. In an appendix, the theory of stimulated Thomson scattering is used to treat the free-electron amplifier

  14. Agents in domestic environments

    OpenAIRE

    van Moergestel, Leo; Langerak, Wouter; Meerstra, Glenn; Nieuwenburg, Niels van; Pape, Franc; Telgen, Daniël; Puik, Erik; meyer, john-jules

    2013-01-01

    Athor supplied : "This paper describes an agent-based architecture for domotics. This architecture is based on requirements about expandability and hardware independence. The heart of the system is a multi-agent system. This system is distributed over several platforms to open the possibility to tie the agents directly to the actuators, sensors and devices involved. This way a level of abstraction is created and all intelligence of the system as a whole is related to the agents involved. A pr...

  15. Culturally Aware Agent Communication

    DEFF Research Database (Denmark)

    Rehm, Matthias; Nakano, Yukiko; Koda, Tomoko;

    2012-01-01

    Agent based interaction in the form of Embodied Conversational Agents (ECAs) has matured over the last decade and agents have become more and more sophisticated in terms of their verbal and nonverbal behavior like facial expressions or gestures. Having such “natural” communication channels...

  16. Riot Control Agents

    Science.gov (United States)

    ... a person has been exposed to riot control agents. Long-term health effects of exposure to riot control agents Prolonged ... person is removed from exposure to riot control agents, long-term health effects are unlikely to occur. How you can ...

  17. Reasoning about emotional agents

    NARCIS (Netherlands)

    Meyer, J.-J.

    2008-01-01

    In this paper we discuss the role of emotions in artificial agent design, and the use of logic in reasoning about the emotional or affective states an agent can reside in. We do so by extending the KARO framework for reasoning about rational agents appropriately. In particular we formalize in this f

  18. Agents modeling agents in information economies

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, J.M.; Durfee, E.H. [Univ. of Michigan, Ann Arbor, MI (United States)

    1996-12-31

    Our goal is to design and build agents that act intelligently when placed in an agent-based information economy, where agents buy and sell services (e.g. thesaurus, search, task planning services, etc.). The economy we are working in is the University of Michigan Digital Library (UMDL), a large scale multidisciplinary effort to build an infrastructure for the delivery of library services. In contrast with a typical economy, an information economy deals in goods and services that are often derived from unique sources (authors, analysts, etc.), so that many goods and services are not interchangeable. Also, the cost of replicating and transporting goods is usually negligible, and the quality of goods and services is difficult to measure objectively: even two sources with essentially the same information might appeal to different audiences. Thus, each agent has its own assessment of the quality of goods and services delivered.

  19. Luminescence optically stimulated: theory and applications

    International Nuclear Information System (INIS)

    The thermally stimulated luminescence (Tl) has occupied an important place in the Solid state physics (FES) by the flexibility of the phenomena, mainly for its applications in the fields of Radiation Physics (FR) and Medical Physics (MF). The reason of this phenomena lies in the fact of the electrons release by the action of heat. Under that same reason, it can be used the action of another stimulant agent for releasing the trapped electrons in the metastable states (EM), this agent is the light which has the same effect that the heat, giving as result the production of light photons at using light in the visible spectra, of different wavelength that the excitation light. This phenomena is called Luminescence optically stimulated (LOE). The LOE has a great impact in the Solid State Physics (FES), dating and now in the use of the phenomena as a dosimetric method, alternate to the Tl, for its use in the ionizing and non-ionizing radiations fields. (Author)

  20. Endothelial Cell-Selective Adhesion Molecule Expression in Hematopoietic Stem/Progenitor Cells Is Essential for Erythropoiesis Recovery after Bone Marrow Injury

    Science.gov (United States)

    Sudo, Takao; Yokota, Takafumi; Okuzaki, Daisuke; Ueda, Tomoaki; Ichii, Michiko; Ishibashi, Tomohiko; Isono, Tomomi; Habuchi, Yoko; Oritani, Kenji; Kanakura, Yuzuru

    2016-01-01

    Numerous red blood cells are generated every second from proliferative progenitor cells under a homeostatic state. Increased erythropoietic activity is required after myelo-suppression as a result of chemo-radio therapies. Our previous study revealed that the endothelial cell-selective adhesion molecule (ESAM), an authentic hematopoietic stem cell marker, plays essential roles in stress-induced hematopoiesis. To determine the physiological importance of ESAM in erythroid recovery, ESAM-knockout (KO) mice were treated with the anti-cancer drug, 5-fluorouracil (5-FU). ESAM-KO mice experienced severe and prolonged anemia after 5-FU treatment compared to wild-type (WT) mice. Eight days after the 5-FU injection, compared to WT mice, ESAM-KO mice showed reduced numbers of erythroid progenitors in bone marrow (BM) and spleen, and reticulocytes in peripheral blood. Megakaryocyte-erythrocyte progenitors (MEPs) from the BM of 5-FU-treated ESAM-KO mice showed reduced burst forming unit-erythrocyte (BFU-E) capacities than those from WT mice. BM transplantation revealed that hematopoietic stem/progenitor cells from ESAM-KO donors were more sensitive to 5-FU treatment than that from WT donors in the WT host mice. However, hematopoietic cells from WT donors transplanted into ESAM-KO host mice could normally reconstitute the erythroid lineage after a BM injury. These results suggested that ESAM expression in hematopoietic cells, but not environmental cells, is critical for hematopoietic recovery. We also found that 5-FU treatment induces the up-regulation of ESAM in primitive erythroid progenitors and macrophages that do not express ESAM under homeostatic conditions. The phenotypic change seen in macrophages might be functionally involved in the interaction between erythroid progenitors and their niche components during stress-induced acute erythropoiesis. Microarray analyses of primitive erythroid progenitors from 5-FU-treated WT and ESAM-KO mice revealed that various signaling

  1. Aromatase inhibitors in stimulated IVF cycles

    Directory of Open Access Journals (Sweden)

    Tournaye Herman

    2011-06-01

    Full Text Available Abstract Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels

  2. Copeptin under glucagon stimulation.

    Science.gov (United States)

    Lewandowski, Krzysztof C; Lewiński, Andrzej; Skowrońska-Jóźwiak, Elżbieta; Stasiak, Magdalena; Horzelski, Wojciech; Brabant, Georg

    2016-05-01

    Stimulation of growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion by glucagon is a standard procedure to assess pituitary dysfunction but the pathomechanism of glucagon action remains unclear. As arginine vasopressin (AVP) may act on the release of both, GH and ACTH, we tested here the role of AVP in GST by measuring a stable precursor fragment, copeptin, which is stoichiometrically secreted with AVP in a 1:1 ratio. ACTH, cortisol, GH, and copeptin were measured at 0, 60, 90, 120, 150, and 180 min during GST in 79 subjects: healthy controls (Group 1, n = 32), subjects with pituitary disease, but with adequate cortisol and GH responses during GST (Group 2, n = 29), and those with overt hypopituitarism (Group 3, n = 18). Copeptin concentrations significantly increased over baseline 150 and 180 min following glucagon stimulation in controls and patients with intact pituitary function but not in hypopituitarism. Copeptin concentrations were stimulated over time and the maximal increment correlated with ACTH, while correlations between copeptin and GH were weaker. Interestingly, copeptin as well as GH secretion was significantly attenuated when comparing subjects within the highest to those in the lowest BMI quartile (p < 0.05). Copeptin is significantly released following glucagon stimulation. As this release is BMI-dependent, the time-dependent relation between copeptin and GH may be obscured, whereas the close relation to ACTH suggests that AVP/copeptin release might be linked to the activation of the adrenal axis. PMID:26578365

  3. Chemical crowd control agents.

    Science.gov (United States)

    Menezes, Ritesh G; Hussain, Syed Ather; Rameez, Mansoor Ali Merchant; Kharoshah, Magdy A; Madadin, Mohammed; Anwar, Naureen; Senthilkumaran, Subramanian

    2016-03-01

    Chemical crowd control agents are also referred to as riot control agents and are mainly used by civil authorities and government agencies to curtail civil disobedience gatherings or processions by large crowds. Common riot control agents used to disperse large numbers of individuals into smaller, less destructive, and more easily controllable numbers include chloroacetophenone, chlorobenzylidenemalononitrile, dibenzoxazepine, diphenylaminearsine, and oleoresin capsicum. In this paper, we discuss the emergency medical care needed by sufferers of acute chemical agent contamination and raise important issues concerning toxicology, safety and health. PMID:26658556

  4. Decontamination Data - Blister Agents

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination efficacy data for blister agents on various building materials using various decontamination solutions This dataset is associated with the following...

  5. Hemoglobin Targets and Blood Transfusions in Hemodialysis Patients without Symptomatic Cardiac Disease Receiving Erythropoietin Therapy

    OpenAIRE

    Foley, Robert N.; Curtis, Bryan M.; Parfrey, Patrick S.

    2008-01-01

    Background and objectives: Optimal hemoglobin targets for chronic kidney disease patients receiving erythropoiesis-stimulating agents remain controversial. The effects of different hemoglobin targets on blood transfusion requirements have not been well characterized, despite their relevance to clinical decision-making.

  6. The FIND-CKD study-a randomized controlled trial of intravenous iron versus oral iron in non-dialysis chronic kidney disease patients : background and rationale

    NARCIS (Netherlands)

    Macdougall, Iain C.; Bock, Andreas; Carrera, Fernando; Eckardt, Kai-Uwe; Gaillard, Carlo; Van Wyck, David; Roubert, Bernard; Cushway, Timothy; Roger, Simon D.

    2014-01-01

    Background. Rigorous data are sparse concerning the optimal route of administration and dosing strategy for iron therapy with or without concomitant erythropoiesis-stimulating agent (ESA) therapy for the management of iron deficiency anaemia in patients with non-dialysis dependent chronic kidney dis

  7. Functionalized polymer nanofibre membranes for protection from chemical warfare stimulants

    Energy Technology Data Exchange (ETDEWEB)

    Ramaseshan, Ramakrishnan [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore (Singapore); Sundarrajan, Subramanian [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore (Singapore); Liu, Yingjun [Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore (Singapore); Barhate, R S [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore (Singapore); Lala, Neeta L [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore (Singapore); Ramakrishna, S [Nanoscience and Nanotechnology Initiative, National University of Singapore, 2 Engineering Drive 3, Singapore 117576, Singapore (Singapore)

    2006-06-28

    A catalyst for the detoxification of nerve agents is synthesized from {beta}-cyclodextrin ({beta}-CD) and o-iodosobenzoic acid (IBA). Functionalized polymer nanofibre membranes from PVC polymer are fabricated with {beta}-CD, IBA, a blend of {beta}-CD+IBA, and the synthesized catalyst. These functionalized nanofibres are then tested for the decontamination of paraoxon, a nerve agent stimulant, and it is observed that the stimulant gets hydrolysed. The kinetics of hydrolysis is investigated using UV spectroscopy. The rates of hydrolysis for different organophosphate hydrolyzing agents are compared. The reactivity and amount of adsorption of these catalysts are of higher capacity than the conventionally used activated charcoal. A new design for protective wear is proposed based on the functionalized nanofibre membrane.

  8. Functionalized polymer nanofibre membranes for protection from chemical warfare stimulants

    International Nuclear Information System (INIS)

    A catalyst for the detoxification of nerve agents is synthesized from β-cyclodextrin (β-CD) and o-iodosobenzoic acid (IBA). Functionalized polymer nanofibre membranes from PVC polymer are fabricated with β-CD, IBA, a blend of β-CD+IBA, and the synthesized catalyst. These functionalized nanofibres are then tested for the decontamination of paraoxon, a nerve agent stimulant, and it is observed that the stimulant gets hydrolysed. The kinetics of hydrolysis is investigated using UV spectroscopy. The rates of hydrolysis for different organophosphate hydrolyzing agents are compared. The reactivity and amount of adsorption of these catalysts are of higher capacity than the conventionally used activated charcoal. A new design for protective wear is proposed based on the functionalized nanofibre membrane

  9. Pharmacological interventions for adolescents and adults with ADHD: stimulant and nonstimulant medications and misuse of prescription stimulants.

    Science.gov (United States)

    Weyandt, Lisa L; Oster, Danielle R; Marraccini, Marisa E; Gudmundsdottir, Bergljot Gyda; Munro, Bailey A; Zavras, Brynheld Martinez; Kuhar, Ben

    2014-01-01

    Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by symptoms of inattention, hyperactivity, and impulsivity that cause functional impairment. Recent research indicates that symptoms persist into adulthood in the majority of cases, with prevalence estimates of approximately 5% in the school age population and 2.5%-4% in the adult population. Although students with ADHD are at greater risk for academic underachievement and psychosocial problems, increasing numbers of students with ADHD are graduating from high school and pursuing higher education. Stimulant medications are considered the first line of pharmacotherapy for individuals with ADHD, including college students. Although preliminary evidence indicates that prescription stimulants are safe and effective for college students with ADHD when used as prescribed, very few controlled studies have been conducted concerning the efficacy of prescription stimulants with college students. In addition, misuse of prescription stimulants has become a serious problem on college campuses across the US and has been recently documented in other countries as well. The purpose of the present systematic review was to investigate the efficacy of prescription stimulants for adolescents and young adults with ADHD and the nonmedical use and misuse of prescription stimulants. Results revealed that both prostimulant and stimulant medications, including lisdexamfetamine dimesylate, methylphenidate, amphetamines, and mixed-amphetamine salts, are effective at reducing ADHD symptoms in adolescents and adults with ADHD. Findings also suggest that individuals with ADHD may have higher rates of stimulant misuse than individuals without the disorder, and characteristics such as sex, race, use of illicit drugs, and academic performance are associated with misuse of stimulant medications. Results also indicate that individuals both with and without ADHD are more likely to misuse short-acting agents

  10. Evaluation of Motivational Effects Induced by Intracranial Self-Stimulation Behavior

    OpenAIRE

    Sagara,Hidenori; Sendo, Toshiaki; Gomita,Yutaka

    2010-01-01

    In the runway model of intracranial self-stimulation (ICSS) experimentation, the experimental animal is timed in running a fixed distance to depress a lever that releases electrical stimulation to an electrode implanted along its medial forebrain bundle. This ICSS has both a reward and a motivational component. Using the runway method and priming stimulation, we designed an experimental method for directly measuring motivation. An assessment of pharmacological agents that are known to influen...

  11. Agent Development Toolkits

    CERN Document Server

    Singh, Aarti; Sharma, A K

    2011-01-01

    Development of agents as well as their wide usage requires good underlying infrastructure. Literature indicates scarcity of agent development tools in initial years of research which limited the exploitation of this beneficial technology. However, today a wide variety of tools are available, for developing robust infrastructure. This technical note provides a deep overview of such tools and contrasts features provided by them.

  12. Radiographic scintiscanning agent

    International Nuclear Information System (INIS)

    A new technetium-based scintiscanning agent has been prepared comprising a water soluble sup(99m)Tc-methanehydroxydiphosphonate in combination with a reducing agent selected from stannous, ferrous, chromous and titanous salts. As an additional stabilizer salts and esters of gentisic or ascorbic acids have been used. (E.G.)

  13. Asimovian Adaptive Agents

    CERN Document Server

    Gordon, D F

    2011-01-01

    The goal of this research is to develop agents that are adaptive and predictable and timely. At first blush, these three requirements seem contradictory. For example, adaptation risks introducing undesirable side effects, thereby making agents' behavior less predictable. Furthermore, although formal verification can assist in ensuring behavioral predictability, it is known to be time-consuming. Our solution to the challenge of satisfying all three requirements is the following. Agents have finite-state automaton plans, which are adapted online via evolutionary learning (perturbation) operators. To ensure that critical behavioral constraints are always satisfied, agents' plans are first formally verified. They are then reverified after every adaptation. If reverification concludes that constraints are violated, the plans are repaired. The main objective of this paper is to improve the efficiency of reverification after learning, so that agents have a sufficiently rapid response time. We present two solutions: ...

  14. How do agents represent?

    Science.gov (United States)

    Ryan, Alex

    Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition — that the brain is a representational device — as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.

  15. Hyperthermia and chemotherapy agent

    International Nuclear Information System (INIS)

    The use of chemotherapeutic agents for the treatment of cancer dates back to the late 19th century, but the modern era of chemotherapy drugs was ushered in during the 1940's with the development of the polyfunctional alkylating agent. Since then, numerous classes of drugs have evolved and the combined use of antineoplastic agents with other treatment modalities such as radiation or heat, remains a large relatively unexplored area. This approach, combining local hyperthermia with chemotherapy agents affords a measure of targeting and selective toxicity not previously available for drugs. In this paper, the effects of adriamycin, bleomycin and cis-platinum are examined. The adjuvant use of heat may also reverse the resistance of hypoxic cells noted for some chemotherapy agents

  16. Blood Contrast Agents Enhance Intrinsic Signals in the Retina: Evidence for an Underlying Blood Volume Component

    OpenAIRE

    Schallek, Jesse; Ts'o, Daniel

    2011-01-01

    Systemic injections of blood contrast agents nigrosin and indocyanine green increased stimulus-evoked reflectance signals in the retina. The enhancement of signal strength is consistent with neurovascular coupling in response to visual stimulation.

  17. Stimulated Black Hole Evaporation

    CERN Document Server

    Spaans, Marco

    2016-01-01

    Black holes are extreme expressions of gravity. Their existence is predicted by Einstein's theory of general relativity and is supported by observations. Black holes obey quantum mechanics and evaporate spontaneously. Here it is shown that a mass rate $R_f\\sim 3\\times 10^{-8} (M_0/M)^{1/2}$ $M_0$ yr$^{-1}$ onto the horizon of a black hole with mass $M$ (in units of solar mass $M_0$) stimulates a black hole into rapid evaporation. Specifically, $\\sim 3 M_0$ black holes can emit a large fraction of their mass, and explode, in $M/R_f \\sim 3\\times 10^7 (M/M_0)^{3/2}$ yr. These stimulated black holes radiate a spectral line power $P \\sim 2\\times 10^{39} (M_0/M)^{1/2}$ erg s$^{-1}$, at a wavelength $\\lambda \\sim 3\\times 10^5 (M/M_0)$ cm. This prediction can be observationally verified.

  18. Raft River well stimulation experiments: geothermal reservoir well stimulation program

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    The Geothermal Reservoir Well Stimulation Program (GRWSP) performed two field experiments at the Raft River KGRA in 1979. Wells RRGP-4 and RRGP-5 were selected for the hydraulic fracture stimulation treatments. The well selection process, fracture treatment design, field execution, stimulation results, and pre- and post-job evaluations are presented.

  19. Dorsal column stimulator applications

    OpenAIRE

    Yampolsky, Claudio; Hem, Santiago; Bendersky, Damián

    2012-01-01

    Background: Spinal cord stimulation (SCS) has been used to treat neuropathic pain since 1967. Following that, technological progress, among other advances, helped SCS become an effective tool to reduce pain. Methods: This article is a non-systematic review of the mechanism of action, indications, results, programming parameters, complications, and cost-effectiveness of SCS. Results: In spite of the existence of several studies that try to prove the mechanism of action of SCS, it still remains...

  20. Motivation and Stimulation

    OpenAIRE

    Macešková, Markéta

    2015-01-01

    The subject of this thesis is the analysis and evaluation of the work environment ( job satisfaction ) in connection with motivation and stimulation in the selected company. The intention of the thesis is to analyze the company, to point out the importance of optimal motivation in connection with an appropriate working environment to identify potential weaknesses and propose solutions for efficient use of the human potential. In the theoretical level, based on studied professional literature,...

  1. Self-Stimulated Undulator Klystron

    OpenAIRE

    Bessonov, E. G.; Osipov, A. L.; Mikhailichenko, A. A.

    2011-01-01

    The Self Stimulated Undulator Klystron (SSUK) and its possible applications in the Particle Accelerator Physics, incoherent Self-Stimulated Undulator Radiation Sources (SSUR) and Free-Electron Lasers (FEL) are discussed.

  2. Nanomaterial-enabled neural stimulation

    OpenAIRE

    Yongchen eWang; Liang eGuo

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a h...

  3. Nanomaterial-Enabled Neural Stimulation

    OpenAIRE

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a h...

  4. Users, Bystanders and Agents

    DEFF Research Database (Denmark)

    Krummheuer, Antonia Lina

    2015-01-01

    Human-agent interaction (HAI), especially in the field of embodied conversational agents (ECA), is mainly construed as dyadic communication between a human user and a virtual agent. This is despite the fact that many application scenarios for future ECAs involve the presence of others. This paper...... the construction of the agent’s identity, and (3) how HAI, as a mediated interaction, is framed by an asymmetric participation framework. The paper concludes by suggesting various participation roles, which may inform development of ECAs....

  5. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  6. Physiological aspects of paired stimulation

    NARCIS (Netherlands)

    Meijler, F.L.; Durrer, D.

    1965-01-01

    In this paper some physiological and clinical aspects of paired stimulation are discussed. I) The augmenting effect of paired stimulation on rnyocardial contractility is due to potentiation (increase in speed of restitution) and fusion of two contractions. 2) While using paired stimulation the oxyg

  7. Renotropic stimulation in rat kidney cell culture

    International Nuclear Information System (INIS)

    A circulating renotropic factor specific for renal cells has been described in rats. The addition of sera obtained from unilaterally nephrectomized (uni) rats 24h after operation compared to sham-operated (sham) rats augments 3H-thymidine incorporation into the DNA of incubating kidney slices approximately 10% - 30%. Attempting to amplify the sensitivity of the assay for this renotropic agent, the authors replaced slices with primary rat kidney cultures. The assay system was based on one previously used for rabbits. The cultured cells were synchronized in their growth phase by a period of protein-free starvation. Compared to sera from sham rats, sera from uni rats showed significant stimulation of thymidine incorporation into DNA, 35.5% +/- 9.3 (SEM), p < .0001, at 16 h; 63.3% +/- 10.0 (SEM), p < .001, at 24 h; and 19.5% +/- 6.5 (SEM), p < .01, at 48 h post operation. Accordingly, the maximal stimulation at 24 h was greater than that previously found using the kidney slice assay. Measurable renotropic activity occurred earlier and over a shorter duration than in rabbits. Stimulation was similar when a D-valine medium, relatively specific for renal epithelial cells, replaced DME medium

  8. Myeloid cell kinetics in mice treated with recombinant interleukin-3, granulocyte colony-stimulating factor (CSF), or granulocyte-macrophage CSF in vivo

    International Nuclear Information System (INIS)

    Myeloid cell kinetics in mice treated with pure hematopoietic growth factors have been investigated using tritiated thymidine labeling and autoradiography. Mice were injected subcutaneously with 125 micrograms/kg granulocyte colony-stimulating factor (G-CSF) (in some cases 5 micrograms/kg), or 10 micrograms/kg of granulocyte-macrophage CSF (GM-CSF), or interleukin-3 (IL-3) every 12 hours for 84 hours. 3HTdR labeling was performed in vivo after 3 days of treatment. G-CSF increased the peripheral neutrophil count 14-fold and increased the proportion and proliferation rate of neutrophilic cells in the marrow, suppressing erythropoiesis at the same time. Newly produced mature cells were released into the circulation within 24 hours of labeling, compared with a normal appearance time of about 96 hours. By contrast, GM-CSF and IL-3 had little effect on either marrow cell kinetics or on the rate of release of mature cells, although GM-CSF did stimulate a 50% increase in peripheral neutrophils. Monocyte production was also increased about eightfold by G-CSF and 1.5-fold by GM-CSF, but their peak release was only slightly accelerated. While the peripheral half-lives of the neutrophilic granulocytes were normal, those of the monocytes were dramatically reduced, perhaps due to sequestration in the tissues for functional purposes. The stimulated monocyte production in the case of G-CSF required an additional five cell cycles, a level that might have repercussions on the progenitor compartments

  9. Agent Standards Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation of the work herein proposed is the development of standards for software autonomous agents. These standards are essential to achieve software...

  10. Programming Service Oriented Agents

    OpenAIRE

    Hirsch, Benjamin; Konnerth, Thomas; Burkhardt, Michael; Albayrak, Sahin

    2010-01-01

    This paper introduces a programming language for service-oriented agents. JADL++ combines the ease of use of scripting-languages with a state-of-the-art service oriented approach which allows the seamless integration of web-services. Furthermore, the language includes OWL-based ontologies for semantic descriptions of data and services, thus allowing agents to make intelligent decisions about service calls.

  11. Adrenal imaging agents

    International Nuclear Information System (INIS)

    The goals of this proposal are the development of selenium-containing analogs of the aromatic amino acids as imaging agents for the pancreas and of the adrenal cortex enzyme inhibitors as imaging agents for adrenal pathology. The objects for this year include (a) the synthesis of methylseleno derivatives of phenylalanine and tryptophan, and (b) the preparation and evaluation of radiolabeled iodobenzoyl derivatives of the selenazole and thiazole analogs of metyrapone and SU-9055

  12. Agent amplified communication

    Energy Technology Data Exchange (ETDEWEB)

    Kautz, H.; Selman, B.; Milewski, A. [AT& T Laboratories, Murray Hill, NJ (United States)

    1996-12-31

    We propose an agent-based framework for assisting and simplifying person-to-person communication for information gathering tasks. As an example, we focus on locating experts for any specified topic. In our approach, the informal person-to-person networks that exist within an organization are used to {open_quotes}referral chain{close_quotes} requests for expertise. User-agents help automate this process. The agents generate referrals by analyzing records of e-mail communication patterns. Simulation results show that the higher responsiveness of an agent-based system can be effectively traded for the higher accuracy of a completely manual approach. Furthermore, preliminary experience with a group of users on a prototype system has shown that useful automatic referrals can be found in practice. Our experience with actual users has also shown that privacy concerns are central to the successful deployment of personal agents: an advanced agent-based system will therefore need to reason about issues involving trust and authority.

  13. Spinal Cord Stimulation

    DEFF Research Database (Denmark)

    Meier, Kaare

    2014-01-01

    Spinal cord stimulation (SCS) is a surgical treatment for chronic neuropathic pain that is refractory to other treatment. Originally described by Shealy et al. in 1967(1), it is used to treat a range of conditions such as complex regional pain syndrome (CRPS I)(2), angina pectoris(3), radicular...... pain after failed back surgery syndrome (FBSS)(4), pain due to peripheral nerve injury, stump pain(5), peripheral vascular disease(6) and diabetic neuropathy(7,8); whereas phantom pain(9), postherpetic neuralgia(10), chronic visceral pain(11), and pain after partial spinal cord injury(12) remain more...... controversial. SCS is not effective in relieving central neuropathic pain states....

  14. Development Block or Stimulant

    DEFF Research Database (Denmark)

    Katznelson, Ron D.; Howells, John

    provide an alternative technical means to those stipulated in Edison's claim 2. Prior work in the economics literature has not addressed the the relation of downstream invention to prior art patent claims. We also show that when the number of patents is plotted against time, there is a surge of patenting...... subsequent to the courts upholding the validity of Edison's claim 2. We argue that Edison's patent had the effect of stimulating downstream invention. This analysis is contrary to several recent papers that have been published in the student-reviewed US law literature that assume Edison's patent was used by...

  15. Transcranial brain stimulation: closing the loop between brain and stimulation

    DEFF Research Database (Denmark)

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    PURPOSE OF REVIEW: To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. RECENT FINDINGS: Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain...... transcranial brain stimulation. Priming interventions or paired associative stimulation can be used to ‘standardize’ the brain-state and hereby, homogenize the group response to stimulation. Neuroanatomical and neurochemical profiling based on magnetic resonance imaging and spectroscopy can capture trait......-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified...

  16. Cutting agents for special metals

    International Nuclear Information System (INIS)

    The quantity of use of special metals has increased year after year in the Plasma Research Institute, Nagoya University, with the development of researches on plasma and nuclear fusion. Most of these special metals are hard to cut, and in order to secure the surface smoothness and dimensional accuracy, considerable efforts are required. The method of experiment is as follows: cutting agents salt water and acetone, rape-seed oil, sulfide and chloride oil and water soluble cutting oil W grade 3; metals to be cut niobium, molybdenum, tantalum, titanium and tungsten; cutting conditions cutting speed 4.7 to 90 m/min, feed 0.07 to 0.2 mm/rev, depth of cut 0.1 to 0.4 mm, tool cemented carbide bit. Chemicals such as tetrachloromethane and trichloroethane give excellent cutting performance, but the toxicity is intense and the stimulative odor exists, accordingly they are hard to use practically. Cutting was easier when the salt water added with acetone was used than the case of rape-seed oil, but salt water is corrosive. Recently, the machining of molybdenum has been often carried out, and the water soluble cutting oil was the best. It is also good for cutting stainless steel, and its lubricating property is improved by adding some additives such as sulfur, chlorine, phosphorus and molybdenum disulfide. However after cutting with it, washing is required. (Kako, I.)

  17. Clastogenicity Potential Screening of Pleurotus pulmonarius and Pleurotus ostreatus Metabolites as Potential Anticancer and Antileukaemic Agents Using Micronucleus Assay

    Directory of Open Access Journals (Sweden)

    E.O. Akanni

    2010-11-01

    Full Text Available Development of anticancer agents that will selectively destroy cancer cells without injury to normal cells has led to the discovery of novel immunotherapeutic agents such as Pleurotus pulmonarius and Pleurotus ostreatus metabolites. This study is to screen the agents of dreadful side effects of causing mutation after a prolonged use. Clastogenicity potential of the novel anti-cancer and antileukaemic agents Pleurotus pulmonarius and Pleurotus ostreatus metabolites was evaluated in this study. Wister rats were grouped into four with the test groups inoculated intraperitoneally at doses 64 and 16 mg/kg as 12.8 and 3.2% of the LD50 into the high and low dose rat groups respectively with each metabolite in a separate experiment. The treated rats were sacrificed after 24, 48 and 72 h post treatment. Cyclophosphamide (clastogen was inoculated into the positive control group at doses 112 and 28 mg/kg w hile saline was used for the negative control group. In all the treatment groups, only the rats in the positive control group formed micronuclei in their bone marrow cells. There was only an increase in the formation of normochromatic and polychromatic erythrocytes in rat groups inoculated with Pleurotus ostreatus metabolites. There is no statistically significant difference (p>0.05 between the 3 post treatment sacrificing periods. Similar result was also obtained for Pleurotus pulmonarius group. The chromosomal damaging potential screening reveals that the Pleurotus ostreatus and Pleurotus pulmonarius metabolites are not clastogenic (genotoxic that is, unlikely to cause cancer producing mutations, but rather enhanced erythropoiesis. They could therefore be useful anticancer agents when the potential is fully explored.

  18. Brain stimulation for intractable epilepsy: Anterior thalamus and responsive stimulation

    OpenAIRE

    2014-01-01

    Despite medications, resective surgery, and vagal nerve stimulation, some patients with epilepsy continue to have seizures. In these patients, other approaches are urgently needed. The biological basis of stimulation of anterior thalamic nucleus and epileptogenic focus is presented. Results from two large randomized controlled trials Stimulation of Anterior Nucleus of Thalamus for Epilepsy (SANTE) and Neuropace pivotal trial are discussed. Neuromodulation provides effective treatment for a se...

  19. 5-Azacytidine stimulates fetal hemoglobin synthesis in anemic baboons.

    OpenAIRE

    DESIMONE, J.; Heller, P; Hall, L; Zwiers, D

    1982-01-01

    In an attempt to stimulate Hb F synthesis in baboons by means other than erythropoietic stress, we considered the possibility that an agent that inhibits methylation of CpG sequences in DNA may be effective. 5-Azacytidine, a cytosine analogue that cannot be methylated, is such an agent. Animals whose packed red cell volume was maintained at approximately 20% by bleeding were given 10 daily intravenous injections of the drug (6 mg/kg) in 12 days. Hb F levels in these animals started to increas...

  20. Agent Oriented Programming进展%Advances in Agent Oriented Programming

    Institute of Scientific and Technical Information of China (English)

    王一川; 石纯一

    2002-01-01

    Agent-oriented programming (AOP) is a framework to develop agents, and it aims to link the gap betweentheory and practical in agent research. The core of an AOP framework is its language and semantics. In this paper,we propose the necessary properties which agents should have, and then give a summary and analysis about differentAOP languages based on these properties.

  1. Stimulated Thomson scattering

    International Nuclear Information System (INIS)

    The theory of stimulated Thomson scattering is investigated both quantum mechanically and classically. Two monochromatic electromagnetic waves of like polarization travelling in opposite directions are allowed to interact for a time tau with the electrons in a collisionless plasma. The electromagnetic waves have frequencies well above the plasma frequency, and their difference frequency is allowed to range upward from the plasma frequency. With the difference frequency well above the plasma frequency, the rate at which energy is transferred from one wave to the other is calculated quantum mechanically, classically from a fluid theory, and classically from an independent electron theory. The rate is calculated in both the homogeneously broadened limit, and in the inhomogeneously broadened limit

  2. Stimulated Cavity-Optomechanics

    CERN Document Server

    Bahl, Gaurav; Tomes, Matthew; Carmon, Tal

    2011-01-01

    Stimulated Brillouin interaction between sound and light, known to be the strongest optical nonlinearity common to all amorphous and crystalline dielectrics, has been widely studied in fibers and bulk materials but rarely in optical microresonators. The possibility of experimentally extending this principle to excite mechanical resonances in photonic microsystems, for sensing and frequency reference applications, has remained largely unexplored. The challenge lies in the fact that microresonators inherently have large free spectral range, while the phase matching considerations for the Brillouin process require optical modes of nearby frequencies but with different wavevectors. We rely on high-order transverse optical modes to relax this limitation. Here we report on the experimental excitation of mechanical resonances ranging from 49 to 1400 MHz by using forward Brillouin scattering. These natural mechanical resonances are excited in ~100 um silica microspheres, and are of a surface-acoustic whispering-galle...

  3. Femtosecond Stimulated Raman Spectroscopy.

    Science.gov (United States)

    Dietze, Daniel R; Mathies, Richard A

    2016-05-01

    Femtosecond stimulated Raman spectroscopy (FSRS) is an ultrafast nonlinear optical technique that provides vibrational structural information with high temporal (sub-50 fs) precision and high spectral (10 cm(-1) ) resolution. Since the first full demonstration of its capabilities ≈15 years ago, FSRS has evolved into a mature technique, giving deep insights into chemical and biochemical reaction dynamics that would be inaccessible with any other technique. It is now being routinely applied to virtually all possible photochemical reactions and systems spanning from single molecules in solution to thin films, bulk crystals and macromolecular proteins. This review starts with an historic overview and discusses the theoretical and experimental concepts behind this technology. Emphasis is put on the current state-of-the-art experimental realization and several variations of FSRS that have been developed. The unique capabilities of FSRS are illustrated through a comprehensive presentation of experiments to date followed by prospects. PMID:26919612

  4. Agents unleashed a public domain look at agent technology

    CERN Document Server

    Wayner, Peter

    1995-01-01

    Agents Unleashed: A Public Domain Look at Agent Technology covers details of building a secure agent realm. The book discusses the technology for creating seamlessly integrated networks that allow programs to move from machine to machine without leaving a trail of havoc; as well as the technical details of how an agent will move through the network, prove its identity, and execute its code without endangering the host. The text also describes the organization of the host's work processing an agent; error messages, bad agent expulsion, and errors in XLISP-agents; and the simulators of errors, f

  5. Stimulated coherent transition radiation

    International Nuclear Information System (INIS)

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed

  6. El agente encubierto

    OpenAIRE

    Anaya Marcos, María del Carmen

    2015-01-01

    [ES] El trabajo versa sobre la figura del agente encubierto. Debemos enmarcar tal medida de investigación dentro del ámbito de la criminalidad organizada. Actualmente, estamos asistiendo a una proliferación de la delincuencia organizada. La sociedad ha evolucionado, y con ella la delincuencia. Fruto de tal evolución fue necesario incluir en nuestra Ley de Enjuiciamiento Criminal medidas extraordinarias de investigación, y una de ellas es el agente encubierto. Se trata de una medida muy polémi...

  7. The PLS agent : agent behavior validation by partial least squares

    OpenAIRE

    Lorscheid, Iris; Meyer, Matthias; Pakur, Sandra; Ringle, Christian

    2014-01-01

    Agent-based modeling is widely applied in the social sciences. However, the validation of agent behavior is challenging and identified as one of the shortcomings in the field. Methods are required to establish empirical links and support the implementation of valid agent models. This paper contributes to this, by introducing the PLS agent concept. This approach shows a way to transfer results about causalities and decision criteria from empirical surveys into an agent-based decision model, th...

  8. Optically stimulated differential impedance spectroscopy

    Science.gov (United States)

    Maxey, Lonnie C; Parks, II, James E; Lewis, Sr., Samuel A; Partridge, Jr., William P

    2014-02-18

    Methods and apparatuses for evaluating a material are described. Embodiments typically involve use of an impedance measurement sensor to measure the impedance of a sample of the material under at least two different states of illumination. The states of illumination may include (a) substantially no optical stimulation, (b) substantial optical stimulation, (c) optical stimulation at a first wavelength of light, (d) optical stimulation at a second wavelength of light, (e) a first level of light intensity, and (f) a second level of light intensity. Typically a difference in impedance between the impedance of the sample at the two states of illumination is measured to determine a characteristic of the material.

  9. Trading Agents for Roaming Users

    OpenAIRE

    Boman, Magnus; Bylund, Markus; Espinoza, Fredrik; Danielson, Mats; Lyback, David

    2002-01-01

    Some roaming users need services to manipulate autonomous processes. Trading agents running on agent trade servers are used as a case in point. We present a solution that provides the agent owners with means to upkeeping their desktop environment, and maintaining their agent trade server processes, via a briefcase service.

  10. Software Agent Techniques in Design

    DEFF Research Database (Denmark)

    Hartvig, Susanne C

    1998-01-01

    This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments.......This paper briefly presents studies of software agent techniques and outline aspects of these which can be applied in design agents in integrated civil engineering design environments....

  11. 13 CFR 107.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. 107.1620 Section 107.1620 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES SBA Financial Assistance...

  12. Programming multi-agent systems

    NARCIS (Netherlands)

    Dastani, Mehdi

    2015-01-01

    With the significant advances in the area of autonomous agents and multi-agent systems in the last decade, promising technologies for the development and engineering of multi-agent systems have emerged. The result is a variety of agent-oriented programming languages, development frameworks, executio

  13. SECOND BUYING AGENT

    CERN Multimedia

    SPL - SERVICES ACHATS

    2000-01-01

    Last year the buying agent LOGITRADE started operations on the CERN site, processing purchasing requests for well-defined families of products up to a certain value. It was planned from the outset that a second buying agent would be brought in to handle the remaining product families. So, according to that plan, the company CHARLES KENDALL will be commencing operations at CERN on 8 May 2000 in Building 73, 1st floor, offices 31 and 35 (phone and fax numbers to be announced).Each buying agent will have its own specific list of product families and will handle purchasing requests up to 10'000 CHF.Whenever possible they will provide the requested supplies at a price (including the cost of their own services) which must be equivalent to or lower than the price mentioned on the purchasing request, changing the supplier if necessary. If a lower price cannot be obtained, agents will provide the necessary administrative support free of charge.To ensure that all orders are processed in the best possible conditions, us...

  14. Radioactive diagnostic agent

    International Nuclear Information System (INIS)

    A dispersion of denatured aggregates of serum albumin to which tin is attached is prepared and lyophilized. A mixture of polycarboxylic acid and a disaccharide or monosaccharide is included in the dispersion in sufficient amount to reduce degradation during lyophilization and aging. The dispersion is suitable for radioactive labelling and use as a diagnostic agent

  15. Developing Enculturated Agents

    DEFF Research Database (Denmark)

    Rehm, Matthias

    Embodied Conversational Agents (ECAs) are complex multimodal systems with rich verbal and nonverbal repertoires. There human-like appearance raises severe expectations regarding natural communicative behaviors on the side of the user. But what is regarded as “natural” is to a large degree dependent...

  16. Biomimetic Emotional Learning Agents

    OpenAIRE

    Kenyon, Samuel H.

    2005-01-01

    This extended abstract proposes a type of AI agent comprised of: an autonomous real-time control system, low-level emotional learning (including a simple knowledge base that links homeostatic/innate drives to sensory perception states), and a novel sliding-priority drive motivation mechanism. Learning occurs in both phylogenetic and ontogenetic training.

  17. Agents of Change

    DEFF Research Database (Denmark)

    Hansen, Jens Aage; Lehmann, Martin

    2004-01-01

    at large, it emphasises universities as key change agents and providers in new learning, including tools such as project based and problem oriented learning (PBL) as well as information and communication technology (ICT); as providers of competent and motivated graduates to fill key positions in society...

  18. The need for agents

    DEFF Research Database (Denmark)

    Abolfazlian, Ali Reza Kian

    1996-01-01

    I denne artikel arbejder vi med begrebet Intelligent Software Agents (ISAs), som autonomous, social, reactive, proactive og subservient computer systemer. Baseret på socialt psykologiske argumenter viser jeg endvidere, hvordan både den menneskelige natur og det teknologiske stadium, som mennesket...

  19. Build Autonomic Agents with ABLE

    Institute of Scientific and Technical Information of China (English)

    吴吉义

    2007-01-01

    The IBM Agent Building and Learning Environment(ABLE) provides a lightweight Java~(TM) agent frame- work,a comprehensive JavaBeansTM library of intelligent software components,a set of development and test tools, and an agent platform.After the introduction to ABLE,classes and interfaces in the ABLE agent framework were put forward.At last an autonomic agent that is an ABLE-based architecture for incrementally building autonomic systems was discussed.

  20. Pharmacological interventions for adolescents and adults with ADHD: stimulant and nonstimulant medications and misuse of prescription stimulants

    Directory of Open Access Journals (Sweden)

    Weyandt LL

    2014-09-01

    characteristics such as sex, race, use of illicit drugs, and academic performance are associated with misuse of stimulant medications. Results also indicate that individuals both with and without ADHD are more likely to misuse short-acting agents than long-acting agents. These findings have implications for intervention, prevention, and future research. Keywords: ADHD symptomatology, pharmacotherapy, nonmedical stimulant use, lisdexamfetamine, methylphenidate, amphetamine

  1. EOR by stimulated microflora

    Energy Technology Data Exchange (ETDEWEB)

    Svarovskaya, L.I.; Altunina, L.K.; Rozhenkova, Z.A.; Bulavin, V.D. [Institute of Petroleum Chemistry, Tomsk (Russian Federation)

    1995-12-31

    A combined microbiological and physico-chemical method for EOR has been developed for flooded West Siberia oil fields with formation temperature of 45{degrees}-95{degrees}C (318-365K). Formation water includes rich and various biocenoses numbering up to 2 x 10{sup 7} cells per ml. Representatives of genera, i.e, Pseudomonas, Bacillus, Actinomyces, Micrococcus, Mycobacterium, Sarcina, etc. were found to be the most widely distributed microorganisms. The method is based on injection of systems exhibiting high oil displacing capacity and at the same time being an additional nitrous nutrient for endemic populations of microorganisms. Their injection into formation water favors biomass growth by 4-6 orders and promotes syntheses of biosurfactants, biopolymers, acids, etc., and gaseous products. The features of residual oil displacement have been studied on laboratory models using a combined microbiological and physico-chemical method. A curve for the yield of residual oil is presented by two peaks. The first peak is stipulated by the washing action of oil displacement system, and the second one by the effect of metabolites produced at stimulation of biogenic processes. Oil displacement index increases by 15%-30%.

  2. Dichotic Stimulation and Mental Retardation.

    Science.gov (United States)

    Mosley, James L.; Virbancic, Mirna I.

    1990-01-01

    This paper reviews literature on the use of dichotic stimulation in individuals with mental retardation, and examines how noninvasive dichotic stimulation relates to hemisphere lateralization. Common findings are discussed concerning direction and magnitude of ear asymmetries, patterns of intrusion errors, and speech lateralization of Down…

  3. Subliminal Stimulation: Hoax or Reality?

    Science.gov (United States)

    Trank, Douglas M.

    Subliminal stimulation is defined as that which is perceived by an individual below the threshold of awareness or cognizance. This article traces the history of research in subliminal stimulation to illustrate that under certain circumstances and conditions, this behavioral phenomenon does occur. Although subliminal stimuli do affect human…

  4. Stimulating Language: Insights from TMS

    Science.gov (United States)

    Devlin, Joseph T.; Watkins, Kate E.

    2007-01-01

    Fifteen years ago, Pascual-Leone and colleagues used transcranial magnetic stimulation (TMS) to investigate speech production in pre-surgical epilepsy patients and in doing so, introduced a novel tool into language research. TMS can be used to non-invasively stimulate a specific cortical region and transiently disrupt information processing. These…

  5. Granulocyte/macrophage colony-stimulating factor and interleukin 3 release from human peripheral blood eosinophils and neutrophils

    OpenAIRE

    1991-01-01

    Human peripheral blood eosinophils released eosinophil survival- enhancing activity when stimulated with the calcium ionophore, ionomycin. The release of activity was detected as early as 3 h after stimulation and was inhibited by an immunomodulating agent, cyclosporin A. The survival-enhancing activity was completely abolished by treatment with anti-interleukin 3 (IL-3) and anti- granulocyte/macrophage colony-stimulating factor (GM-CSF) monoclonal antibodies. Moreover, IL-3 and GM-CSF were m...

  6. Actions and Agents

    OpenAIRE

    Alonso, E.

    2014-01-01

    In this chapter the notion of agency in AI is presented..It has been argued that in order to behave rationally in prevalent software applications artificial entities would have to be autonomous and adaptive. Besides, rather than working with single, isolated systems the new trend in AI would need to focus on inherently social entities in the form of multi-agent systems. The chapter begins by introducing the notion of action in traditional AI systems, deliberative and reactive. Next, the i...

  7. Towards Soft Computing Agents

    Czech Academy of Sciences Publication Activity Database

    Neruda, Roman; Krušina, Pavel; Petrová, Zuzana

    2000-01-01

    Roč. 10, č. 5 (2000), s. 859-868. ISSN 1210-0552. [SOFSEM 2000 Workshop on Soft Computing. Milovy, 27.11.2000-28.11.2000] R&D Projects: GA ČR GA201/00/1489; GA ČR GA201/99/P057 Institutional research plan: AV0Z1030915 Keywords : hybrid systems * intelligent agents Subject RIV: BA - General Mathematics

  8. Sunscreening Agents: A Review

    OpenAIRE

    Latha, M. S.; Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; B R Naveen Kumar

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food an...

  9. Perioperative allergy: uncommon agents.

    Science.gov (United States)

    Caimmi, S; Caimmi, D; Cardinale, F; Indinnimeo, L; Crisafulli, G; Peroni, D G; Marseglia, G L

    2011-01-01

    Anesthesia may often be considered as a high-risk procedure and anaphylaxis remains a major cause of concern for anesthetists who routinely administer many potentially allergenic agents. Neuromuscular blocking agents, latex and antibiotics are the substances involved in most of the reported reactions. Besides these three agents, a wide variety of substances may cause an anaphylactic reaction during anesthesia. Basically all the administered drugs or substances may be potential causes of anaphylaxis. Among them, those reported the most in literature include hypnotics, opioids, local anesthetics, colloids, dye, Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), Iodinated Contrast Media (ICM), antiseptics, aprotinin, ethylene oxyde and formaldehyde, and protamine and heparins. No premedication can effectively prevent an allergic reaction and a systematic preoperative screening is not justified for all patients; nevertheless, an allergy specialist should evaluate those patients with a history of anesthesia-related allergy. Patients must be fully informed of investigation results, and advised to provide a detailed report prior to future anesthesia. PMID:22014927

  10. Advanced scale conditioning agents

    International Nuclear Information System (INIS)

    A technical description of Advanced Scale Conditioning Agents (ASCA) technology was published in the May-June 2003 edition of the Nuclear Plant Journal. That article described the development of programs of advanced scale conditioning agents and specific types to maintain the secondary side of steam generators within a pressurized water reactor free of deposited corrosion products and corrosion-inducing contaminants to ensure their long-term operation. This article describes the first two plant applications of advanced scale conditioning agents implemented at Southern Nuclear Operating Company's Vogtle Units 1 and 2 during their 2002 scheduled outages to minimize tube degradation and maintain full power operation using the most effective techniques while minimizing outage costs. The goal was to remove three to four fuel cycles of deposits from each steam generator so that after future chemical cleaning activities, ASCAs could be used to maintain the cleanliness of the steam generators without the need for additional chemical cleaning efforts. The goal was achieved as well as several other benefits that resulted in cost savings to the plant

  11. SAM : Semantic Agent Model for SWRL rule-based agents

    OpenAIRE

    Subercaze, Julien; Maret, Pierre

    2010-01-01

    International audience SemanticWeb technologies are part of multi-agent engineering, especially regarding knowledge base support. Recent advances in the field of logic for the semantic web enable a new range of applications. Among them, programming agents based on semantic rules is a promising field. In this paper we present a semantic agent model that allows SWRL programming of agents. Our approach, based on the extended finite state machine concept, results in a three layers architecture...

  12. Nanomaterial-Enabled Neural Stimulation.

    Science.gov (United States)

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed. PMID:27013938

  13. Nanomaterial-enabled neural stimulation

    Directory of Open Access Journals (Sweden)

    Yongchen eWang

    2016-03-01

    Full Text Available Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed.

  14. Electrical stimulation in exercise training

    Science.gov (United States)

    Kroll, Walter

    1994-01-01

    Electrical stimulation has a long history of use in medicine dating back to 46 A.D. when the Roman physician Largus found the electrical discharge of torpedo fishes useful in the treatment of pain produced by headache and gout. A rival Greek physician, Dioscorides, discounted the value of the torpedo fish for headache relief but did recommend its use in the treatment of hemorrhoids. In 1745, the Leyden jar and various sized electrostatic generators were used to treat angina pectoris, epilepsy, hemiplegia, kidney stones, and sciatica. Benjamin Franklin used an electrical device to treat successfully a young woman suffering from convulsive fits. In the late 1800's battery powered hydroelectric baths were used to treat chronic inflammation of the uterus while electrified athletic supporters were advertised for the treatment of male problems. Fortunately, such an amusing early history of the simple beginnings of electrical stimulation did not prevent eventual development of a variety of useful therapeutic and rehabilitative applications of electrical stimulation. Over the centuries electrical stimulation has survived as a modality in the treatment of various medical disorders with its primary application being in the rehabilitation area. Recently, a surge of new interest in electrical stimulation has been kindled by the work of a Russian sport scientist who reported remarkable muscle strength and endurance improvements in elite athletes. Yakov Kots reported his research on electric stimulation and strength improvements in 1977 at a Canadian-Soviet Exchange Symposium held at Concordia University in Montreal. Since then an explosion of new studies has been seen in both sport science and in medicine. Based upon the reported works of Kots and the present surge of new investigations, one could be misled as to the origin of electrical stimulation as a technique to increase muscle strength. As a matter of fact, electric stimulation has been used as a technique to improve

  15. Divalent cation ionophores stimulate resorption and inhibit DNA synthesis in cultured fetal rat bone

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo, J.A.; Raisz, L.G.

    1981-06-01

    Two divalent cation ionophores, A23187 and Ionomycin, which are selective for calcium, stimulated the resorption of fetal rat long bones in organ culture at 0.1 to 1 micromolar but not at higher concentrations. Both agents inhibited DNA synthesis at concentrations that stimulated resorption. These results might explain the differences in ionophore effects on bone previously reported, and they imply that cell replication is not required for osteoclast formation in fetal rat long bone cultures.

  16. Peripheral Neuropathy and Agent Orange

    Science.gov (United States)

    ... Enter ZIP code here Peripheral Neuropathy and Agent Orange VA presumes Veterans' early-onset peripheral neuropathy is related to their exposure to Agent Orange or other herbicides during service when the disease ...

  17. Agents Play Mix-game

    CERN Document Server

    Gou, C

    2005-01-01

    In mix-game which is an extension of minority game, there are two groups of agents; group1 plays the majority game, but the group2 plays the minority game. This paper studies the change of the average winnings of agents and volatilities vs. the change of mixture of agents in mix-game model. It finds that the correlations between the average winnings of agents and the mean of local volatilities are different with different combinations of agent memory length when the proportion of agents in group 1 increases. This study result suggests that memory length of agents in group1 be smaller than that of agent in group2 when mix-game model is used to simulate the financial markets.

  18. The Power Trading Agent Competition

    OpenAIRE

    Ketter, W.; Collins, J.; REDDY, P; Flath, C.

    2011-01-01

    This is the specification for the Power Trading Agent Competition for 2011 (Power TAC 2011). Agents are simulations of electrical power brokers, who must compete with each other for both power production and consumption, and manage their portfolios.

  19. Vasopressin and angiotensin II stimulate oxygen uptake in the perfused rat hindlimb

    DEFF Research Database (Denmark)

    Colquhoun, E Q; Hettiarachchi, M; Ye, J M;

    1988-01-01

    Vasopressin and angiotensin II markedly stimulated oxygen uptake in the perfused rat hindlimb. The increase due to each agent approached 70% of the basal rate, and was greater than that produced by a maximal concentration of norepinephrine. Half-maximal stimulation occurred at 60 pM vasopressin, 0.......5 nM angiotensin II and 10 nM norepinephrine. Angiotensins I and III were less potent than angiotensin II. For each agent, the dose-dependent increase in oxygen uptake coincided with a dose-dependent increase in perfusion pressure. The effects of both vasopressin and angiotensin to increase oxygen...

  20. Mediating Performance Through Virtual Agents

    OpenAIRE

    Giannachi, Gabriella; Gillies, Marco; Kaye, Nick; Swapp, David

    2009-01-01

    This paper presents the process of creation of virtual agents used in a virtual reality performance. The performance aimed to investigate how drama and performance could inform the creation of virtual agents and also how virtual reality could raise questions for drama and performance. The virtual agents were based on the performance of 2 actors. This paper describes the process of preparing the actors, capturing their performances and transferring them to the virtual agents. A second set of a...

  1. Dobutamine use for arrhythmia induction during electrical programmed heart stimulation

    International Nuclear Information System (INIS)

    isoproterenol is the traditionally used drug for incrementing arrhythmia induction when this induction is not achieved during electric programmed heart stimulation under basal conditions. Dobutamine is an adrenergic agent, chemical precursor of isoproterenol, which can be an alternative for inducing arrhythmia during electrical programmed heart stimulation (PES). Patients and methods: a retrospective comparative study of the experience with dobutamine for inducing arrhythmia during electrical programmed heart stimulation was performed. The following data were collected: number of studies, data about the patient (medical record, age, gender, and study indication) protocol of programmed electrical stimulation, basal and under dobutamine or isoproterenol, and result of the study. Isoproterenol was used in doses of 1 to 3 micrograms per minute until the basal heart rate was incremented at least in 25%. Dobutamine was used in doses of 10 to 40 micrograms per kg of body weight, until obtaining the same increment in the basal heart rate. Results: 1054 electrophysiological studies were evaluated. In 144 patients (group A) isoproterenol was used and in 140, dobutamine (group B). In A group the mean age was 39.2 ± 16.2 and 58.3% were females. In-group B, mean age was 41.9 ± 18.6 and 51% were females. The most frequent symptom was palpitation and the most commonly induced arrhythmia was AV nodal reentry tachycardia in both groups. The induction of arrhythmia during the electrical programmed heat stimulation under drugs was similar in-group A (isoproterenol) respect to group B (dobutamine). Conclusions: There were no statistical significant differences in the induction of arrhythmia during electrical programmed heart stimulation using dobutamine or isoproterenol. Dobutamine may be safe and may be successfully used as an alternative to isoproterenol for arrhythmia induction during electrical programmed stimulation

  2. Cultural Differentiation of Negotiating Agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, D.

    2012-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national cultu

  3. Cultural differentiation of negotiating agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, T.

    2010-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national cultu

  4. Demultiplexer circuit for neural stimulation

    Science.gov (United States)

    Wessendorf, Kurt O; Okandan, Murat; Pearson, Sean

    2012-10-09

    A demultiplexer circuit is disclosed which can be used with a conventional neural stimulator to extend the number of electrodes which can be activated. The demultiplexer circuit, which is formed on a semiconductor substrate containing a power supply that provides all the dc electrical power for operation of the circuit, includes digital latches that receive and store addressing information from the neural stimulator one bit at a time. This addressing information is used to program one or more 1:2.sup.N demultiplexers in the demultiplexer circuit which then route neural stimulation signals from the neural stimulator to an electrode array which is connected to the outputs of the 1:2.sup.N demultiplexer. The demultiplexer circuit allows the number of individual electrodes in the electrode array to be increased by a factor of 2.sup.N with N generally being in a range of 2-4.

  5. Enteral feeding without pancreatic stimulation

    DEFF Research Database (Denmark)

    Kaushik, Neeraj; Pietraszewski, Marie; Holst, Jens Juul;

    2005-01-01

    OBJECTIVE: All forms of commonly practiced enteral feeding techniques stimulate pancreatic secretion, and only intravenous feeding avoids it. In this study, we explored the possibility of more distal enteral infusions of tube feeds to see whether activation of the ileal brake mechanism can result...... in enteral feeding without pancreatic stimulation, with particular reference to trypsin, because the avoidance of trypsin stimulation may optimize enteral feeding in acute pancreatitis. METHODS: The pancreatic secretory responses to feeding were studied in 36 healthy volunteers by standard double...... plasma glucagon-like peptide-1 and peptide YY concentrations. CONCLUSIONS: Our results suggest that enteral feeding can be given without stimulating pancreatic trypsin secretion provided it is delivered into the mid-distal jejunum. The mechanism may involve activation of the ileal brake mechanism....

  6. Collaborating with Autonomous Agents

    Science.gov (United States)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  7. Deep Brain Stimulation for Parkinson's Disease

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS NINDS Deep Brain Stimulation for Parkinson's Disease Information Page Condensed from ... and Information Publicaciones en Español What is Deep Brain Stimulation for Parkinson's Disease? Deep brain stimulation (DBS) ...

  8. Agentes de información Information Agents

    Directory of Open Access Journals (Sweden)

    Alfonso López Yepes

    2005-12-01

    Full Text Available Este artículo realiza un repaso sobre las tipologías de agentes de información y describe aspectos como movilidad, racionalidad y adaptatividad, y el ajuste final de estos conceptos a entornos distribuidos como Internet, donde este tipo de agentes tienen un amplio grado de aplicación. Asimismo, se propone una arquitectura de agentes para un sistema multiagente de recuperación de información donde se aplica un paradigma documental basado en el concepto de ciclo documental.This article summarizes the main information agent types reflecting on issues such as mobility, rationality, adaptability and the final adjustment of this concepts to distributed environments such as the Internet, where this kind of agents has wide range application. Likewise, an information agent architecture is proposed to create a multi-agent information retrieval system in which a documentary paradigm based on the documentary cycle is developed.

  9. Secure Mobile Trade Agent

    Directory of Open Access Journals (Sweden)

    Musbah M. Aqe

    2007-01-01

    Full Text Available E-commerce on the internet has the ability to produce millions of transactions and a great number of merchants whose supply merchandise over the internet. As a result, it is difficult for entities to roam over every site on the internet and choose the best merchandise to trade. So, in this paper we introduced a mobile trade agent that visit the sites to gather and evaluate the information from merchant servers and decide to trade goods on behalf of the user. We observed that the combination of public key cryptosystem with distributed object technology make this proposed scheme more secure and efficient than the already existed schemes.

  10. Configuring Computational Agents

    Czech Academy of Sciences Publication Activity Database

    Beuster, G.; Neruda, Roman

    Halifax : Saint Mary's University, 2004 - (Zhuge, H.; Cheung, W.; Liu, J.), s. 57-62 ISBN 0-9734039-8-5. [International Workshop on Knowledge Grid and Grid Intelligence /2./. Beijing (CN), 20.09.2004] R&D Projects: GA AV ČR 1ET100300419 Grant ostatní: CZ-DE project(XX) CZE-03/023 Institutional research plan: CEZ:AV0Z1030915 Keywords : Bang 3 * multi-agent systems * computational intelligence models Subject RIV: BA - General Mathematics

  11. Transcutaneous Spinal Direct Current Stimulation

    OpenAIRE

    Cogiamanian, Filippo; Ardolino, Gianluca; Vergari, Maurizio; Ferrucci, Roberta; Ciocca, Matteo; Scelzo, Emma; Barbieri, Sergio; Priori, Alberto

    2012-01-01

    In the past 10 years renewed interest has centered on non-invasive transcutaneous weak direct currents applied over the scalp to modulate cortical excitability (“brain polarization” or transcranial direct current stimulation, tDCS). Extensive literature shows that tDCS induces marked changes in cortical excitability that outlast stimulation. Aiming at developing a new, non-invasive, approach to spinal cord neuromodulation we assessed the after-effects of thoracic transcutaneous spinal DC stim...

  12. Transcranial electrical stimulation: An introduction

    CERN Document Server

    Tarazona, Carlos G; Chávez, Laura; Andrade, Sebastián

    2015-01-01

    The main objective of the electrical stimulation of the brain is to generate action potentials from the application of electromagnetic fields. Among the available techniques, transcranial electrical stimulation (TES) represents a popular method of administration that has the advantage of being non-invasive and economically more affordable. This article aims to briefly introduce the reader into the understanding of TES in terms of the physics involved as well as for some of the relevant results of studies applying this technique.

  13. Economics of nuclear gas stimulation

    International Nuclear Information System (INIS)

    Nuclear stimulation of the Mesaverde Formation in the Piceance Basin appears to be the only available method that can release the contained gas economically. In the Rulison Field alone estimates show six to eight trillion cubic feet of gas may be made available by nuclear means, and possibly one hundred trillion cubic feet could be released in the Piceance Basin. Several problems remain to be solved before this tremendous gas reserve can be tapped. Among these are (1) rates of production following nuclear stimulation; (2) costs of nuclear stimulation; (3) radioactivity of the chimney gas; and (4) development of the ideal type of device to carry out the stimulations. Each of these problems is discussed in detail with possible solutions suggested. First and foremost is the rate at which gas can be delivered following nuclear stimulation. Calculations have been made for expected production behavior following a 5-kiloton device and a 40-kiloton device with different permeabilities. These are shown, along with conventional production history. The calculations show that rates of production will be sufficient if costs can be controlled. Costs of nuclear stimulation must be drastically reduced for a commercial process. Project Rulison will cost approximately $3.7 million, excluding lease costs, preliminary tests, and well costs. At such prices, nothing can possibly be commercial; however, these costs can come down in a logical step-wise fashion. Radiation contamination of the gas remains a problem. Three possible solutions to this problem are included. (author)

  14. Holograms as Teaching Agents

    Science.gov (United States)

    Walker, Robin A.

    2013-02-01

    Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

  15. Amphoteric surface active agents

    Directory of Open Access Journals (Sweden)

    Eissa, A.M. F.

    1995-10-01

    Full Text Available 2-[trimethyl ammonium, triethyl ammonium, pyridinium and 2-amino pyridinium] alkanoates, four series of surface active agents containing carbon chain C12, C14, C16 and C18carbon atoms, were prepared. Their structures were characterized by microanalysis, infrared (IR and nuclear magnetic resonance (NMR. Surface and interfacial tension, Krafft point, wetting time, emulsification power, foaming height and critical micelle concentration (cmc were determined and a comparative study was made between their chemical structure and surface active properties. Antimicrobial activity of these surfactants was also determined.

    Se prepararon cuatro series de agentes tensioactivos del tipo 2-[trimetil amonio, trietil amonio, piridinio y 2-amino piridinio] alcanoatos, que contienen cadenas carbonadas con C12, C14, C16 y C18 átomos de carbono.
    Se determinaron la tensión superficial e interfacial, el punto de Krafft, el tiempo humectante, el poder de emulsionamiento, la altura espumante y la concentración critica de miscela (cmc y se hizo un estudio comparativo entre la estructura química y sus propiedades tensioactivas. Se determinó también la actividad antimicrobiana de estos tensioactivos. Estas estructuras se caracterizaron por microanálisis, infrarrojo (IR y resonancia magnética nuclear (RMN.

  16. Contrast agents for MRI

    International Nuclear Information System (INIS)

    Contrast agents are divided into two categories. The first one is paramagnetic compounds, including lanthanides like gadolinium, which mainly reduce the longitudinal (T1) relaxation property and result in a brighter signal. The second class consists of super-paramagnetic magnetic nanoparticles (SPMNPs) such as iron oxides, which have a strong effect on the transversal (T2) relaxation properties. SPMNPs have the potential to be utilized as excellent probes for magnetic resonance imaging (MRI). For instance, clinically benign iron oxide and engineered ferrite nanoparticles provide a good MRI probing capability for clinical applications. Furthermore, the limited magnetic property and inability to escape from the reticuloendothelial system (RES) of the used nanoparticles impede their further advancement. Therefore, it is necessary to develop the engineered magnetic nanoparticle probes for the next-generation molecular MRI. Considering the importance of MRI in diagnosing diseases, this paper presents an overview of recent scientific achievements in the development of new synthetic SPMNP probes whereby the sensitive and target-specific observation of biological events at the molecular and cellular levels is feasible. - Highlights: • This paper studies the contrast agents for MRI. • Fe―Co alloys and Mn-ferrites exhibit suitable contrast enhancement. • Nonhydrolytic thermal-decomposition synthetic method is suitable to produce MNPs. • This method allows controlling the size, magnetic dopants, magneto-crystalline anisotropy. • The increase in the superparamagnetic size leads to the contrast-enhancement

  17. Agent-oriented Software Engineering

    Institute of Scientific and Technical Information of China (English)

    GUAN Xu; CHENG Ming; LIU Bao

    2001-01-01

    An increasing number of computer systems are being viewed in terms of autonomous agents.Most people believe that agent-oriented approach is well suited to design and build complex systems. Yet. todate, little effort had been devoted to discuss the advantages of agent-oriented approach as a mainstreamsoftware engineering paradigm. Here both of this issues and the relation between object-oriented and agent-oriented will be argued. we describe an agent-oriented methodology and provide a quote for designing anauction system.

  18. Neuroprotection trek--the next generation: neuromodulation I. Techniques--deep brain stimulation, vagus nerve stimulation, and transcranial magnetic stimulation

    Science.gov (United States)

    Andrews, Russell J.

    2003-01-01

    Neuromodulation denotes controlled electrical stimulation of the central or peripheral nervous system. The three forms of neuromodulation described in this paper-deep brain stimulation, vagus nerve stimulation, and transcranial magnetic stimulation-were chosen primarily for their demonstrated or potential clinical usefulness. Deep brain stimulation is a completely implanted technique for improving movement disorders, such as Parkinson's disease, by very focal electrical stimulation of the brain-a technique that employs well-established hardware (electrode and pulse generator/battery). Vagus nerve stimulation is similar to deep brain stimulation in being well-established (for the treatment of refractory epilepsy), completely implanted, and having hardware that can be considered standard at the present time. Vagus nerve stimulation differs from deep brain stimulation, however, in that afferent stimulation of the vagus nerve results in diffuse effects on many regions throughout the brain. Although use of deep brain stimulation for applications beyond movement disorders will no doubt involve placing the stimulating electrode(s) in regions other than the thalamus, subthalamus, or globus pallidus, the use of vagus nerve stimulation for applications beyond epilepsy-for example, depression and eating disorders-is unlikely to require altering the hardware significantly (although stimulation protocols may differ). Transcranial magnetic stimulation is an example of an external or non-implanted, intermittent (at least given the current state of the hardware) stimulation technique, the clinical value of which for neuromodulation and neuroprotection remains to be determined.

  19. Learning models of intelligent agents

    Energy Technology Data Exchange (ETDEWEB)

    Carmel, D.; Markovitch, S. [Computer Science Dept., Haifa (Israel)

    1996-12-31

    Agents that operate in a multi-agent system need an efficient strategy to handle their encounters with other agents involved. Searching for an optimal interactive strategy is a hard problem because it depends mostly on the behavior of the others. In this work, interaction among agents is represented as a repeated two-player game, where the agents` objective is to look for a strategy that maximizes their expected sum of rewards in the game. We assume that agents` strategies can be modeled as finite automata. A model-based approach is presented as a possible method for learning an effective interactive strategy. First, we describe how an agent should find an optimal strategy against a given model. Second, we present an unsupervised algorithm that infers a model of the opponent`s automaton from its input/output behavior. A set of experiments that show the potential merit of the algorithm is reported as well.

  20. Flexible, secure agent development framework

    Science.gov (United States)

    Goldsmith; Steven Y.

    2009-04-07

    While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.

  1. UTBot: A Virtual Agent Platform for Teaching Agent System Design

    Directory of Open Access Journals (Sweden)

    In-Cheol Kim

    2007-02-01

    Full Text Available We introduce UTBot, a virtual agent platform for teaching agent system design. UTBot implements a client for the Unreal Tournament game server and Gamebots system. It provides students with the basic functionality required to start developing their own intelligent virtual agents to play autonomously UT games. UTBot includes a generic agent architecture, CAA (Context-sensitive Agent Architecture, a domain-specific world model, a visualization tool, several basic strategies (represented by internal modes and internal behaviors, and skills (represented by external behaviors. The CAA architecture can support complex long-term behaviors as well as reactive short-term behaviors. It also realizes high context-sensitivity of behaviors. We also discuss our experience using UTBot as a pedagogical tool for teaching agent system design in undergraduate Artificial Intelligence course.

  2. Mushrooms as therapeutic agents

    Directory of Open Access Journals (Sweden)

    Sushila Rathee

    2012-04-01

    Full Text Available Mushrooms have been known for their nutritional and culinary values and used as medicines and tonics by humans for ages. In modern terms, they can be considered as functional foods which can provide health benefits beyond the traditional nutrients. There are monographs that cover the medicinal and healing properties of some individual traditional mushrooms. There has been a recent upsurge of interest in mushrooms not only as a health food which is rich in protein but also as a source of biologically active compounds of medicinal value which include complementary medicine/dietary supplements for anticancer, antiviral, hepatoprotective, immunopotentiating and hypocholesterolemic agents. However the mechanisms of the various health benefits of mushrooms to humans still require intensive investigation, especially given the emergence of new evidence of their health benefits. In the present paper the medicinal potential of mushrooms is being discussed.

  3. Microencapsulation of chemotherapeutic agents

    International Nuclear Information System (INIS)

    Mixing various amounts of chemotherapeutic agents such as cisplatinum, 5-fluorouracil, mitomycin-C, and adriamycin with polymers such as poly-d, 1-lactide, ethylhydroxyethylcellulose, and polycaprolactone, several kinds of microcapsules were made. Among them, microcapsule made from ethylhydroxyethylcellulose showed best yield. Under light microscopy, the capsules were observed as particles with refractive properties. For the basic toxicity test, intraarterial administration of cisplatinum was done in 6 adult mongrel dogs. Follow-up angiography was accomplished in 2 wk intervals for 6 wks. Despite no significant difference in the histopathological examination between the embolized and normal kidneys, follow-up angiogram showed atrophy of renal cortex and diminished numbers of arterial branches in the embolized kidneys. In order to identify the structural properties of microcapsules, and to determine the drug content and the rate of release, further experiment is thought to be necessary. (Author)

  4. Hepatocytes as Immunological Agents.

    Science.gov (United States)

    Crispe, Ian N

    2016-01-01

    Hepatocytes are targeted for infection by a number of major human pathogens, including hepatitis B virus, hepatitis C virus, and malaria. However, hepatocytes are also immunological agents in their own right. In systemic immunity, they are central in the acute-phase response, which floods the circulation with defensive proteins during diverse stresses, including ischemia, physical trauma, and sepsis. Hepatocytes express a variety of innate immune receptors and, when challenged with pathogen- or damage-associated molecular patterns, can deliver cell-autonomous innate immune responses that may result in host defense or in immunopathology. Important human pathogens have evolved mechanisms to subvert these responses. Finally, hepatocytes talk directly to T cells, resulting in a bias toward immune tolerance. PMID:26685314

  5. Deep brain stimulation: new techniques.

    Science.gov (United States)

    Hariz, Marwan

    2014-01-01

    The technology of the hardware used in deep brain stimulation (DBS), and the mode of delivering the stimulation have not significantly evolved since the start of the modern era of DBS 25 years ago. However, new technology is now being developed along several avenues. New features of the implantable pulse generator (IPG) allow fractionation of the electric current into variable proportions between different contacts of the multi-polar lead. Another design consists in leads that allow selective current steering from directionally placed electrode contacts that would deliver the stimulation in a specific direction or even create a directional shaped electric field that would conform to the anatomy of the brain target aimed at, avoiding adjacent structures, and thus avoiding side effects. Closed loop adaptive stimulation technologies are being developed, allowing a tracking of the pathological local field potential of the brain target, and delivering automatically the stimulation to suppress the pathological activity as soon as it is detected and for as long as needed. This feature may contribute to a DBS therapy "on demand", instead of continuously. Finally, advances in imaging technology are providing "new" brain targets, and increasingly allowing DBS to be performed accurately while avoiding the risks of microelectrode recording. PMID:24262179

  6. Agent Assignment for Process Management: Pattern Based Agent Performance Evaluation

    Science.gov (United States)

    Jablonski, Stefan; Talib, Ramzan

    In almost all workflow management system the role concept is determined once at the introduction of workflow application and is not reevaluated to observe how successfully certain processes are performed by the authorized agents. This paper describes an approach which evaluates how agents are working successfully and feed this information back for future agent assignment to achieve maximum business benefit for the enterprise. The approach is called Pattern based Agent Performance Evaluation (PAPE) and is based on machine learning technique combined with post processing technique. We report on the result of our experiments and discuss issues and improvement of our approach.

  7. Action research through stimulated recall

    Science.gov (United States)

    O'Brien, John

    1993-12-01

    The emphasis in classroom learning research has moved from process-product models to the mediating process paradigm. The stimulated-recall interview and thik aloud techniques are the two main processes that have been used in attempts to find out what goes on inside students' heads while they are learning. For example, this researcher has used the stimulated-recall interview technique to identify the workplace thinking of a marine science researcher, and the in-class thinking of a year eleven biology student. Such studies as these have produced findings with important implications for the classroom teacher in the role of action researcher. This paper describes how to conduct stimulated-recall interviews and discusses some classroom implications from the two studies.

  8. Odor Classification using Agent Technology

    Directory of Open Access Journals (Sweden)

    Sigeru OMATU

    2014-03-01

    Full Text Available In order to measure and classify odors, Quartz Crystal Microbalance (QCM can be used. In the present study, seven QCM sensors and three different odors are used. The system has been developed as a virtual organization of agents using an agent platform called PANGEA (Platform for Automatic coNstruction of orGanizations of intElligent Agents. This is a platform for developing open multi-agent systems, specifically those including organizational aspects. The main reason for the use of agents is the scalability of the platform, i.e. the way in which it models the services. The system models functionalities as services inside the agents, or as Service Oriented Approach (SOA architecture compliant services using Web Services. This way the adaptation of the odor classification systems with new algorithms, tools and classification techniques is allowed.

  9. Stability of Evolving Agent Populations

    CERN Document Server

    Briscoe, G

    2007-01-01

    Stability is perhaps the most desired feature in the systems that we design. It is important for us to be able to predict the response of a Multi-Agent System (MAS) to various environmental conditions prior to its actual deployment. The Chli-DeWilde agent stability measure views a MAS as a discrete time Markov chain with a potentially unknown transition probabilities. A MAS is considered to be stable when its state, a stochastic process, has converged to an equilibrium distribution. We investigate an extension of their agent stability definition to include MASs with evolutionary dynamics, focusing on evolving agent populations. Additionally, using our extended agent stability measure, we construct an entropy-based definition for the degree of instability. An example system, the Digital Ecosystem, is considered in detail to investigate the stability of an evolving agent population through simulations. The results are consistent with the original Chli-DeWilde measure.

  10. Agent-based enterprise integration

    Energy Technology Data Exchange (ETDEWEB)

    N. M. Berry; C. M. Pancerella

    1998-12-01

    The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. The enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of the effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses the planned future work.

  11. Deep brain stimulation: Current status

    Directory of Open Access Journals (Sweden)

    Sanjay Pandey

    2015-01-01

    Full Text Available In the last two decades, applications of deep brain stimulation (DBS have expanded rapidly in the field of neurosciences. The most common indications for DBS are Parkinson′s disease, medically refractory seizures, essential tremors, and primary dystonia. This device has also been used as an investigational tool in patients having Tourette′s syndrome, tardive dyskinesia, and refractory seizures. In the field of psychiatry, DBS has been used for the treatment of refractory obsessive compulsive disorder and depression. The complications are mainly related to surgery, the device, and its stimulation. This article provides an overview of the current status and recent advances in the field of DBS.

  12. Mobile Agents for Digital Signage

    OpenAIRE

    SATOH, Ichiro

    2010-01-01

    International audience This paper presents an agent-based framework for building and operating context-aware multimedia content on digital signage in public/private spaces. It enables active and multimedia content to be composed from mobile agents, which can travel from computer to computer and provide multimedia content for advertising or user-assistant services to users. The framework automatically deploys their agents at computers near to their current positions to provide advertising o...

  13. An agent for ecological deliberation

    OpenAIRE

    Debenham, John; Sierra, Carles

    2010-01-01

    An agent architecture supports the two forms of deliberation used by human agents. Cartesian, constructivist rationalism leads to game theory, decision theory and logical models. Ecological rationalism leads to deliberative actions that are derived from agents’ prior interactions and are not designed; i.e., they are strictly emergent. This paper aims to address the scant attention paid by the agent community to the predominant form of deliberation used by mankind.

  14. Agent factory: towards social robots

    OpenAIRE

    O'Hare, G. M. P.; Duffy, Brian R.; Collier, Rem; Rooney, Colm, (Thesis); O'Donoghue, Ruadhan

    1999-01-01

    This paper advocates the application of multi-agent techniques in the realisation of social robotic behaviour. We present the Social Robot Architecture, which integrates the key elements of agent-hood and robotics in a coherent and systematic manner. This architecture seamlessly integrates, real world robots, multi-agent development tools, and VRML visualisation tools into a coherent whole. Using these elements, we deliver a development environment, which facilitates rapid prototyping of soci...

  15. Agent Systems in Software Engineering

    OpenAIRE

    Lazarou, Vasilios S.; Gardikiotis, Spyridon K.; Malevris, Nicos

    2008-01-01

    In this chapter, the application of multi-agent systems to tackle the software engineering task was outlined. The concentration was on the employment of agent technology in order to deal with distributed software systems and mainly distributed database applications and web applications. The rationale behind utilizing agent technology has to do with the multi-tier architecture and the associated inherent complication of distributed applications and the required interoperability of software res...

  16. Research on Negotiating Agent Development

    Institute of Scientific and Technical Information of China (English)

    WEI Ding-guo; PENG Hong

    2004-01-01

    The paper presents a flexible and effective method of development of negotiating agents.A strategy specification, which is specified by a state chart and defeasible rules, can be dynamically inserted into an agent shell incorporating a state chart interpreter and a defeasible logic inference engine, in order to yield a desirable agent.The set of desirable criteria and rules is required to be justified with different context of the application.

  17. Extending Agent Languages for Autonomy

    OpenAIRE

    Meneguzzi, Felipe Rech

    2008-01-01

    BDI agent languages provide a useful abstraction for complex systems comprised of interactive autonomous entities, but they have been used mostly in the context of single agents with a static plan library of behaviours invoked reactively. These languages provide a theoretically sound basis for agent design but are very limited in providing direct support for autonomy and societal cooperation needed for large scale systems. Some techniques for autonomy and cooperation have been explored in the...

  18. Radioactive scanning agents with stabilizer

    International Nuclear Information System (INIS)

    Stable compositions useful as technetium 99-based scintigraphic agents comprise gentisyl alcohol or a pharmaceutically-acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in pertechnetate-99m (sup(99m)TcOsub(4)sup(-)) solution. The compositions are especially useful in combination with a phosphate or phosphonate material that carries the radionuclide to bone, thus providing a skeletal imaging agent

  19. Aromatic A-ring analogues of orobanchol, new germination stimulants for seeds of parasitic weeds

    NARCIS (Netherlands)

    Malik, H.; Kohlen, W.; Jamil, M.; Rutjes, F.P.J.T.; Zwanenburg, B.

    2011-01-01

    Strigolactones are signaling compounds in plants of increasing importance. In this paper the focus is on their activity as germinating agents for seeds of parasitic weeds. The syntheses of aromatic A-ring analogues of the germination stimulant orobanchol have been described. Starting substrate is th

  20. Chemosensory stimulation during sleep - Arousal responses to gustatory stimulation.

    Science.gov (United States)

    Stuck, B A; Moutsis, T T; Bingel, U; Sommer, J U

    2016-05-13

    The processing of nociceptive, visual, vibrotactile, thermal and acoustic stimuli during sleep has been extensively investigated in the past. Recently, interest has focused on the impact of olfactory stimulation on sleep. In contrast to all other sensory systems, olfactory stimulation does not lead to an increased arousal frequency, regardless of hedonicity and concentration. The impact of the second chemosensory system, gustation, on sleep however has not been investigated to date. Twenty-one normosmic and normogeusic volunteers of both genders, aged 19-33years, participated in the trial. Stimulation was performed with a gustometer using the following aqueous solutions: saccharose 20% (sweet), sodium chloride (NaCl) 7.5% (salty), citrate 5% (sour), and quinine 0.02% (bitter). A tasteless solution was used as negative control. Capsaicin, a strong trigeminal stimulus, served as positive control. Primary outcome was arousal frequency per stimulus in each sleep stage, as assessed with polysomnography. The frequency of arousals decreased in deeper sleep stages (N1: 211 arousals of 333 stimuli=63%, N2: 676/2728=25%, N3: 43/1378=3%, REM: 57/1010=6%). Statistically significant differences in terms of arousal frequency were found in N2 between the negative control and NaCl 100μl (pCapsaicin led to complete awakenings in 94% of stimuli (30/32). These results demonstrate that gustatory stimulation during sleep induces arousals depending on stimulus intensity and sleep stage, which is different to olfactory stimulation and may be related to differences in central processing of the two chemosensory systems. PMID:26921652

  1. Technetium diagnostic agent and carrier

    International Nuclear Information System (INIS)

    A stable sup(99m)Tc-labelled radioactive diagnostic agent is produced by contacting sup(99m)Tc-containing pertechnetate with a non-radioactive carrier comprising a chelating agent, a water-soluble reducing agent and a stabilizer. The stabilizer is chosen from ascorbic acid and erythorbic acid and their pharmaceutically acceptable salts and esters. A mole ratio of more than 100 moles ascorbic or erythorbic acid to 1 mole of reducing agent provides a stable composition at high levels of radioactivity

  2. Relational agents: A critical review

    DEFF Research Database (Denmark)

    Campbell, Robert H.; Grimshaw, Mark Nicholas; Green, Gill

    2009-01-01

    and non-player characters that can actively participate in such relationships. The focus of this review is relational agents, agents that can build long term socioemotional relationships with users. In virtual worlds, such agents are just starting to emerge; they are more common in other environments...... but remain few and far between. This review critically assesses the progress of relational agent development and research since their inception in 2005, proposes new areas of research and considers the potential for their exploitation in virtual worlds....

  3. A monoclonal thyroid-stimulating antibody

    OpenAIRE

    Ando, Takao; Latif, Rauf; Pritsker, Alla; Moran, Thomas; Nagayama, Yuji; Davies, Terry F.

    2002-01-01

    The thyrotropin receptor, also known as the thyroid-stimulating hormone receptor (TSHR), is the primary antigen of Graves disease. Stimulating TSHR antibodies are the cause of thyroid overstimulation and were originally called long-acting thyroid stimulators due to their prolonged action. Here we report the successful cloning and characterization of a monoclonal antibody (MS-1) with TSHR-stimulating activity. The thyroid-stimulating activity of MS-1 was evident at IgG concentrations as low as...

  4. Incorporating BDI Agents into Human-Agent Decision Making Research

    Science.gov (United States)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  5. Plasmids encoding therapeutic agents

    Science.gov (United States)

    Keener, William K.

    2007-08-07

    Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal extensions of the fusion protein include the maltose binding protein and a Factor Xa protease site. C-terminal extensions include a hydrophobic linker, an L domain motif peptide, a KDEL ER retention signal, another Factor Xa protease site, an out-of-frame buforin II coding sequence, the lacZ.alpha. peptide, and a polyhistidine tag. More than twenty derivatives of plasmid pWKK-500 are described. Plasmids pWKK-700 and pWKK-800 are similar to pWKK-500 wherein the DP178-encoding sequence is substituted by RANTES- and SDF-1-encoding sequences, respectively. Plasmid pWKK-900 is similar to pWKK-500 wherein the HIV protease cleavable linker is substituted by a lethal factor (LF) peptide-cleavable linker.

  6. Gastrointestinal scanning agent

    International Nuclear Information System (INIS)

    An easily prepared radiolabeled gastrointestinal scanning agent is described. Technetium-99m has ideal characteristics for imaging the upper and lower GI tract and determining stomach emptying and intestinal transit time when used with an insoluble particulate material. For example, crystalline and amorphous calcium phosphate particles can be effectively labeled in a one-step process using sup(99m)TcO4 and SnCl2. These labeled particles have insignificant mass and when administered orally pass through the GI tract unchanged, without affecting the handling and density of the intestinal contents. Visualization of the esophageal entry into the stomach, the greater and lesser curvatures of the stomach, ejection into the duodenum, and rates of passage through the upper and lower GI tract are obtained. The slurry of sup(99m)TC particulate can be given rectally by enema. Good images of the cecum and the ascending, transverse, and descending colon are obtained. Mucosal folds and the splenic and hepatic flexures are visualized. The resilience of the large intestine is also readily visualized by pneumocolonographic techniques. (author)

  7. Optimizing performance by conflict stimulation

    NARCIS (Netherlands)

    Van de Vliert, E; De Dreu, C K W

    1994-01-01

    To enhance the quality of group decision making, to promote affective acceptance of decisions by all participants involved, or to increase joint outcomes, a principal party or a third party may stimulate social conflict. We argue that when conflict focuses on identity issues, when tension level is h

  8. Thermally stimulated scattering in plasmas

    DEFF Research Database (Denmark)

    Dysthe, K. B.; Mjølhus, E.; Pécseli, H. L.;

    1985-01-01

    A theory for stimulated scattering of a laser beam is formulated where the dominant nonlinearity is the ohmic heating of the plasma. The analysis is carried out with particular reference to experimental investigations of CO2 laser heating of linear discharge plasma. In the conditions characterizing...

  9. Ovarian stimulation and embryo quality

    NARCIS (Netherlands)

    Baart, Esther; Macklon, Nick S.; Fauser, Bart J. C. M.

    2009-01-01

    To Study the effects of different ovarian stimulation approaches on oocyte and embryo quality, it is imperative to assess embryo quality with a reliable and objective method. Embryos rated as high quality by standardized morphological assessment are associated with higher implantation and pregnancy

  10. Deep brain stimulation in psychiatry

    Directory of Open Access Journals (Sweden)

    Poznić-Ješić Milana

    2014-01-01

    Full Text Available Introduction. Deep brain stimulation is a stereotactic neurosurgical method used in the treatment of Parkinson’s disease and some other movement disorders. The application of deep brain stimulation in the treatment of certain psychiatric disorders has been intensively investigated taking into account the current knowledge of neurobiological basis of mood regulation, cognition, and behaviour. This paper has been aimed at presenting the available data on experience in the application of deep brain stimulation in the treatment of psychiatric disorders. It gives an overview of scientific and professional literature, bearing in mind all the contemporary approaches in the treatment of certain psychiatric disorders. Research results available so far in the treatment of treatment-resistant depression, obsessive-compulsive disorder, Gilles de la Tourette syndrome, addiction and Alzheimer’s dementia, are affirmative concerning the efficacy of the method and low risk of adverse effects. Deep brain stimulation, as a relatively new neurosurgical method in the treatment of psychiatric disorders, is being intensively developed, and it is certainly going to be one of the treatments of choice, primarily of treatment-resistant disorders.

  11. Stimulation of phagocytosis by sulforaphane

    Energy Technology Data Exchange (ETDEWEB)

    Suganuma, Hiroyuki, E-mail: hsuganu1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Fahey, Jed W., E-mail: jfahey@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Bryan, Kelley E., E-mail: kbryanm1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Healy, Zachary R., E-mail: zhealy1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Talalay, Paul, E-mail: ptalalay@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States)

    2011-02-04

    Research highlights: {yields} Sulforaphane stimulates the phagocytosis of RAW 264.7 macrophages under conditions of serum deprivation. {yields} This effect does not require Nrf2-dependent induction of phase 2 genes. {yields} Inactivation of macrophage migration inhibitory factor (MIF) by sulforaphane may be involved in stimulation of phagocytosis by sulforaphane. -- Abstract: Sulforaphane, a major isothiocyanate derived from cruciferous vegetables, protects living systems against electrophile toxicity, oxidative stress, inflammation, and radiation. A major protective mechanism is the induction of a network of endogenous cytoprotective (phase 2) genes that are regulated by transcription factor Nrf2. To obtain a more detailed understanding of the anti-inflammatory and immunomodulatory effects of sulforaphane, we evaluated its effect on the phagocytosis activity of RAW 264.7 murine macrophage-like cells by measuring the uptake of 2-{mu}m diameter polystyrene beads. Sulforaphane raised the phagocytosis activity of RAW 264.7 cells but only in the absence or presence of low concentrations (1%) of fetal bovine serum. Higher serum concentrations depressed phagocytosis and abolished its stimulation by sulforaphane. This stimulation did not depend on the induction of Nrf2-regulated genes since it occurred in peritoneal macrophages of nrf2{sup -/-} mice. Moreover, a potent triterpenoid inducer of Nrf2-dependent genes did not stimulate phagocytosis, whereas sulforaphane and another isothiocyanate (benzyl isothiocyanate) had comparable inducer potencies. It has been shown recently that sulforaphane is a potent and direct inactivator of macrophage migration inhibitory factor (MIF), an inflammatory cytokine. Moreover, the addition of recombinant MIF to RAW 264.7 cells attenuated phagocytosis, but sulforaphane-inactivated MIF did not affect phagocytosis. The inactivation of MIF may therefore be involved in the phagocytosis-enhancing activity of sulforaphane.

  12. Stimulation of phagocytosis by sulforaphane

    International Nuclear Information System (INIS)

    Research highlights: → Sulforaphane stimulates the phagocytosis of RAW 264.7 macrophages under conditions of serum deprivation. → This effect does not require Nrf2-dependent induction of phase 2 genes. → Inactivation of macrophage migration inhibitory factor (MIF) by sulforaphane may be involved in stimulation of phagocytosis by sulforaphane. -- Abstract: Sulforaphane, a major isothiocyanate derived from cruciferous vegetables, protects living systems against electrophile toxicity, oxidative stress, inflammation, and radiation. A major protective mechanism is the induction of a network of endogenous cytoprotective (phase 2) genes that are regulated by transcription factor Nrf2. To obtain a more detailed understanding of the anti-inflammatory and immunomodulatory effects of sulforaphane, we evaluated its effect on the phagocytosis activity of RAW 264.7 murine macrophage-like cells by measuring the uptake of 2-μm diameter polystyrene beads. Sulforaphane raised the phagocytosis activity of RAW 264.7 cells but only in the absence or presence of low concentrations (1%) of fetal bovine serum. Higher serum concentrations depressed phagocytosis and abolished its stimulation by sulforaphane. This stimulation did not depend on the induction of Nrf2-regulated genes since it occurred in peritoneal macrophages of nrf2-/- mice. Moreover, a potent triterpenoid inducer of Nrf2-dependent genes did not stimulate phagocytosis, whereas sulforaphane and another isothiocyanate (benzyl isothiocyanate) had comparable inducer potencies. It has been shown recently that sulforaphane is a potent and direct inactivator of macrophage migration inhibitory factor (MIF), an inflammatory cytokine. Moreover, the addition of recombinant MIF to RAW 264.7 cells attenuated phagocytosis, but sulforaphane-inactivated MIF did not affect phagocytosis. The inactivation of MIF may therefore be involved in the phagocytosis-enhancing activity of sulforaphane.

  13. 2012 Survey of clothing agents

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Clothing agents take part in China International Clothing and Accessories Fairs ( CHIC ) year by year. In order to attracting investment, they compared with each other at improving their originality and service levels. At the exhibition brands manufacturers and agents had a face-to-face communication,

  14. Topical agents in burn care

    Directory of Open Access Journals (Sweden)

    Momčilović Dragan

    2002-01-01

    Full Text Available Introduction Understanding of fluid shifts and recognition of the importance of early and appropriate fluid replacement therapy have significantly reduced mortality in the early post burn period. After the bum patient successfully passes the resuscitation period, the burn wound represents the greatest threat to survival. History Since the dawn of civilization, man has been trying to find an agent which would help burn wounds heal, and at the same time, not harm general condition of the injured. It was not until the XX century, after the discovery of antibiotics, when this condition was fulfilled. In 1968, combining silver and sulfadiazine, fox made silver-sulfadiazine, which is a 1% hydro-soluble cream and a superior agent in topical treatment of burns today. Current topical agents None of the topical antimicrobial agents available today, alone or combined, have the characteristics of ideal prophylactic agents, but they eliminate colonization of burn wound, and invasive infections are infrequent. With an excellent spectrum of activity, low toxicity, and ease of application with minimal pain, silver-sulfadiazine is still the most frequently used topical agent. Conclusion The incidence of invasive infections and overall mortality have been significantly reduced after introduction of topical burn wound antimicrobial agents into practice. In most burn patients the drug of choice for prophylaxis is silver sulfadiazine. Other agents may be useful in certain clinical situations.

  15. Agent Roles in Human Teams

    OpenAIRE

    Lewis, M.; Sycara, K.; Payne, T.R.

    2003-01-01

    In this paper, we describe results of a series of experiments investigating the effects of agent aiding on human teams. The role an agent played, its task, and the ease with which it communicated with its human teammates all influenced team behavior. Team supporting tasks such as relaying and reminding seemed particularly effective.

  16. Effects of Anesthetic Agent Propofol on Postoperative Sex Hormone Levels

    Science.gov (United States)

    Kim, H.; Ku, S.-Y.; Kim, H. C.; Suh, C. S.; Kim, S. H.; Choi, Y. M.

    2016-01-01

    Introduction: Several studies have found anesthetic agents including propofol in ovarian follicular fluid. However, little is known about the effect of anesthetic agents on ovarian function. We aimed to investigate whether there were differences in the postoperative levels of sex hormones when propofol was used as the anesthetic agent. Methods: A retrospective review was done of 80 patients who underwent ovarian surgery, with 72 infertile women serving as controls. Patients were included in the study if their serum estradiol (E2) and follicle stimulating hormone (FSH) levels were measured during their first postoperative menstrual cycle. Results: Patients were grouped according to the use or non-use of propofol as follows: propofol group (n = 39) and non-propofol group (n = 41). The control group did not undergo surgery. Postoperative E2 levels did not differ between the three groups, but FSH levels were significantly higher in the patients who had undergone surgery compared to controls (p < 0.05). Post-hoc analysis of E2 and FSH levels in the propofol and non-propofol groups did not show any significant differences. Conclusions: The use of propofol did not result in any differences compared to other anesthetic agents in terms of postoperative sex hormone levels after gynecologic surgery. The type of anesthetic agent does not seem to affect the postoperative levels of female sex hormones.

  17. Intelligent Agents in Physics Education

    Science.gov (United States)

    Sánchez-Guzmán, D.; Mora, César

    2010-07-01

    Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design; like learning and mentoring tools. In this work we discuss the definition of what an intelligent agent is; how they are applied; how they look like; recent implementations of agents; agents as support in the learning process, more precisely intelligent tutors; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents. Also we present an Intelligent Tutor applied as a tool for improving high-school students' skills and reasoning for the first five topics of Mechanics curricula.

  18. Markov Tracking for Agent Coordination

    Science.gov (United States)

    Washington, Richard; Lau, Sonie (Technical Monitor)

    1998-01-01

    Partially observable Markov decision processes (POMDPs) axe an attractive representation for representing agent behavior, since they capture uncertainty in both the agent's state and its actions. However, finding an optimal policy for POMDPs in general is computationally difficult. In this paper we present Markov Tracking, a restricted problem of coordinating actions with an agent or process represented as a POMDP Because the actions coordinate with the agent rather than influence its behavior, the optimal solution to this problem can be computed locally and quickly. We also demonstrate the use of the technique on sequential POMDPs, which can be used to model a behavior that follows a linear, acyclic trajectory through a series of states. By imposing a "windowing" restriction that restricts the number of possible alternatives considered at any moment to a fixed size, a coordinating action can be calculated in constant time, making this amenable to coordination with complex agents.

  19. Stimulating the Comfort of Textile Electrodes in Wearable Neuromuscular Electrical Stimulation

    OpenAIRE

    Hui Zhou; Yi Lu; Wanzhen Chen; Zhen Wu; Haiqing Zou; Ludovic Krundel; Guanglin Li

    2015-01-01

    Textile electrodes are becoming an attractive means in the facilitation of surface electrical stimulation. However, the stimulation comfort of textile electrodes and the mechanism behind stimulation discomfort is still unknown. In this study, a textile stimulation electrode was developed using conductive fabrics and then its impedance spectroscopy, stimulation thresholds, and stimulation comfort were quantitatively assessed and compared with those of a wet textile electrode and a hydrogel ele...

  20. Agent Communications using Distributed Metaobjects

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, Steven Y.; Spires, Shannon V.

    1999-06-10

    There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

  1. Mobile agent driven by aspect

    Directory of Open Access Journals (Sweden)

    Youssef Hannad

    2010-11-01

    Full Text Available Domain application of mobile agents is quite large. They are used for network management and the monitoring of complex architecture. Mobile agent is also essential into specific software architecture such that adaptable grid architecture. Even if the concept of mobile agent seems to be obvious, the development is always complex because it needs to understand network features but also security features and negotiation algorithms. We present a work about an application of aspects dedicated to mobile agent development over a local network. At this level, the underlying protocol is called jini and allows managing several essential concepts such that short transaction and permission management. Three subsets of aspects are defined in this work. A part is for the description of agent host and its security level, accessible resource, etc. A second part is about mobile agent and their collaboration. This means how they can operate on an agent host with the respect of the execution context. All the results are illustrated through a distributed monitoring application called DMA. Its main objective is the observation of component servers.

  2. Stimulated emission and black holes

    International Nuclear Information System (INIS)

    The probability of a black hole emitting m particles when n particles are incident on the black hole was first derived by Bekenstein and Meisels, and later, using a different method, by Panangaden and Wald. In another paper by Bekenstein, it was argued that black holes should have stimulated emission in all modes including the nonsuperradiant ones. In this paper, we use a model based on quantum field theory. We show that Bose-Einstein statistics enhances the probability for particles to scatter in the same direction. We also prove that a black hole is equivalent to a perfect blackbody surrounded by a mirror. In our model, the black hole does not exhibit stimulated emission in nonsuperradiant modes. We also compare the black hole to a gray body

  3. Electrical stimulation of experimental nonunions

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, R.R.; Luethi, U.; Dueland, R.T.; Perren, S.M.

    Hypertrophic and oligotrophic nonunions were prepared by resection of a portion of the proximal ulna in dogs. In the hypertrophic nonunions, 20 muamps of direct current for eight weeks produced an increase in bone formation compared to the opposite control limb by radiography, photometry, point counting of new bone, and growth rate by sequential fluorochrome labeling and the dynamic uptake of 99mTc-labeled methylene disphosphonate. Oligotrophic nonunions were treated by plating and aspiration grafting in addition to direct-current stimulation. Ony the point counting of new bone showed a significant increase in bone formation with stimulation. Sequential fluorochrome labeling demonstrated that the new bone was laid down on existing bone and not primarily adjacent to the cathode within the fibrous nonunion. This finding supports the cell-mediated rather than physicochemical effect of electrostimulation.

  4. Electrical stimulation of experimental nonunions

    International Nuclear Information System (INIS)

    Hypertrophic and oligotrophic nonunions were prepared by resection of a portion of the proximal ulna in dogs. In the hypertrophic nonunions, 20 muamps of direct current for eight weeks produced an increase in bone formation compared to the opposite control limb by radiography, photometry, point counting of new bone, and growth rate by sequential fluorochrome labeling and the dynamic uptake of 99mTc-labeled methylene disphosphonate. Oligotrophic nonunions were treated by plating and aspiration grafting in addition to direct-current stimulation. Ony the point counting of new bone showed a significant increase in bone formation with stimulation. Sequential fluorochrome labeling demonstrated that the new bone was laid down on existing bone and not primarily adjacent to the cathode within the fibrous nonunion. This finding supports the cell-mediated rather than physicochemical effect of electrostimulation

  5. Tactile Stimulation and Consumer Response.

    OpenAIRE

    Hornik, Jacob

    1992-01-01

    Tactile behavior is a basic communication form as well as an expression of interpersonal involvement. This article presents three studies offering evidence for the positive role of casual interpersonal touch on consumer behavior. More specifically, it provides initial support for the view that tactile stimulation in various consumer behavior situations enhances the positive feeling for and evaluation of both the external stimuli and the touching source. Further, customers touched by a request...

  6. Stimulated Superconductivity at Strong Coupling

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Ning; Dong, Xi; Silverstein, Eva; Torroba, Gonzalo; /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC

    2011-08-12

    Stimulating a system with time dependent sources can enhance instabilities, thus increasing the critical temperature at which the system transitions to interesting low-temperature phases such as superconductivity or superfluidity. After reviewing this phenomenon in non-equilibrium BCS theory (and its marginal fermi liquid generalization) we analyze the effect in holographic superconductors. We exhibit a simple regime in which the transition temperature increases parametrically as we increase the frequency of the time-dependent source.

  7. Ventricular Stimulation After Myocardial Infarction

    OpenAIRE

    Béatrice Brembilla-Perrot

    2011-01-01

    Ventricular stimulation after myocardial infarction (MI) is still recommended (class IB) in patients with syncope and left ventricular ejection fraction (LVEF) more than 30-35%, in asymptomatic patients with a LVEF between 30-40% and with non sustained ventricular tachycardia (VT) patients at Holter monitoring. It can also identify patients at high risk of arrhythmic events in the early post-MI period. Combined with imaging methods PVS could be widely used again during VT ablation.

  8. Deep brain stimulation: new directions.

    Science.gov (United States)

    Ostergard, T; Miller, J P

    2014-12-01

    The role of deep brain stimulation (DBS) in the treatment of movement disorders is well established, but there has recently been a proliferation of additional indications that have been shown to be amenable to this technology. The combination of innovative approaches to neural interface technology with novel target identification based on previously discovered clinical effects of lesioning procedures has led to a fundamental paradigm for new directions in the application of DBS. The historical use of neurosurgical lesioning procedures in the treatment of psychiatric diseases such as obsessive compulsive disorder provided an initial opportunity to expand the use of DBS. The list is rapidly expanding and now includes major depressive disorder, Tourette's syndrome, addiction disorders, and eating disorders. Keen observations by neurosurgeons using these devices have lead to the incidental discovery of treatments for diseases without previous neurosurgical treatments. These discoveries are breaking new ground in the treatment of disorders of cognition, headache syndromes, disorders of consciousness, and epilepsy. Two features of DBS make it well-suited for treatment of disorders of nervous system function. First, the reversible, non-lesional nature of DBS allows for investigation of new targets without the morbidity of permanent side effects. Second, the programmable nature of DBS allows practitioners to alter stimulation patterns to minimize side effects and potentially improve efficacy through reprogramming. More importantly, proper scientific evaluation of new targets is aided by the ability to turn stimulation on and off with evaluators blinded to the stimulation status. Knowledge of these emerging therapies is important for practitioners, as there are many situations where a single target can effectively treat the symptoms of more than one disease. The intersection of advances in neuromodulation, neurophysiology, neuroimaging, and functional neuroanatomy has

  9. Higher education stimulating creative enterprise

    OpenAIRE

    Ely, Philip; Campbell, Frances

    2011-01-01

    This report summarises the research undertaken by the Business & Community School at the University for the Creative Arts (UCA), analysing ways that higher ediucation (HEIs) can support, and indeed stimulate, the creative economy. The research, in collaboration with the Arts University College Bournemouth (AUCB) and the University of Winchester, serves as a mere snapshot of the numerous ways that Universities engage with the diverse industries under the 'creative' nomenclature and of the ver...

  10. Intelligent Farmer Agent for Multi-Agent Ecological Simulations Optimization

    OpenAIRE

    Filipe Cruz; António Pereira; Pedro Valente; Pedro Duarte; Luis Paulo Reis

    2007-01-01

    This paper presents the development of a bivalve farmer agent interacting with a realistic ecological simulation system. The purpose of the farmer agent is to determine the best combinations of bivalve seeding areas in a large region, maximizing the production without exceeding the total allowed seeding area. A system based on simulated annealing, tabu search, genetic algorithms and reinforcement learning, was developed to minimize the number of iterations required to unravel a semi-optimum s...

  11. MDE and Mobile Agents : another reflexion on the agent migration

    OpenAIRE

    Gherbi, Tahar; Borne, Isabelle; Meslati, Djamel

    2009-01-01

    International audience Model Driven Engineering (MDE) is a software development approach family based on the use of models in the software construction. It allows the exploitation of models to simulate, estimate, understand, communicate and produce code. Mobile agents are a very interesting technology to develop applications for mobile and distributed environments. A mobile agent is essentially a computer program that acts autonomously on behalf of a user and travels through a network of h...

  12. Gastric stimulation for weight loss

    Institute of Scientific and Technical Information of China (English)

    Meir Mizrahi; Ami Ben Ya'acov; Yaron Ilan

    2012-01-01

    The prevalence of obesity is growing to epidemic proportions,and there is clearly a need for minimally invasive therapies with few adverse effects that allow for sustained weight loss.Behavior and lifestyle therapy are safe treatments for obesity in the short term,but the durability of the weight loss is limited.Although promising obesity drugs are in development,the currently available drugs lack efficacy or have unacceptable side effects.Surgery leads to long-term weight loss,but it is associated with morbidity and mortality.Gastric electrical stimulation (GES) has received increasing attention as a potential tool for treating obesity and gastrointestinal dysmotility disorders.GES is a promising,minimally invasive,safe,and effective method for treating obesity.External gastric pacing is aimed at alteration of the motility of the gastrointestinal tract in a way that will alter absorption due to alteration of transit time.In addition,data from animal models and preliminary data from human trials suggest a role for the gut-brain axis in the mechanism of GES.This may involve alteration of secretion of hormones associated with hunger or satiety.Patient selection for gastric stimulation therapy seems to be an important determinant of the treatment's outcome.Here,we review the current status,potential mechanisms of action,and possible future applications of gastric stimulation for obesity.

  13. Optical stimulated luminescence (OSL) dating

    International Nuclear Information System (INIS)

    Since the pioneering work by Huntley et al. (1985), optical dating is being increasingly recognised as an important technique for establishing a time frame of deposition of sediments (Aitken, 1998). Optical dating differs from thermoluminescence (TL) dating in that visible/infrared light from lasers or LEDs (light-emitting-diodes) is used as a means of stimulation, in contrast to thermal stimulation. It has several advantages over TL dating: (i) the resetting of the OSL (optically stimulated luminescence) clock is more effective than that of TL clock; for sediments transported under water or in other situations where the sediment grains have undergone inhomogeneous bleaching, this property ensures that ages based on optical dating are generally more reliable than TL ages, (ii) the optical dating technique is non-destructive, and multiple readouts of the optical signal is possible; this feature has resulted in the development of single-aliquot and single-grain protocols (Murray and Wintle, 1999; Banerjee et al. 1999), (iii) the sample is not heated as in TL; thus, spurious luminescence is avoided and there is a significant reduction in blackbody radiation. Dating of materials which change phase on heating is also practical, and finally, (iv) thermal quenching of luminescence is negligible, allowing accurate estimation of kinetic parameters using standard techniques and providing access to deep OSL traps. This characteristic may be helpful in extending the limits of optical dating beyond the last 150 ka from a global point of view

  14. Knowledge mining using intelligent agents

    CERN Document Server

    Dehuri, Satchidananda

    2010-01-01

    ""Knowledge Mining Using Intelligent Agents"" explores the concept of knowledge discovery processes and enhances decision-making capability through the use of intelligent agents like ants, termites and honey bees. In order to provide readers with an integrated set of concepts and techniques for understanding knowledge discovery and its practical utility, this book blends two distinct disciplines - data mining and knowledge discovery process, and intelligent agents-based computing (swarm intelligence and computational intelligence). For the more advanced reader, researchers, and decision/policy

  15. Agent-oriented Software Engineering

    Institute of Scientific and Technical Information of China (English)

    MingCheng; XuGuan; BaoLiu

    2004-01-01

    An increasing number of computer systems are being viewed in terms of autonomous agents.Most people believe that agent-oriented approach is well suited to designing and building complex systems. Yet, to date, little effort had been devoted to discussing the advantages of agent-oriented approach as a mainstream software engineering paradiam.Here both of this issues and the relation between object-oriented and agentoriented will be argued.We describe an agent-oriented methodology and provide a quote for designing a auction system.

  16. Has Dialysis Payment Reform Led to Initial Racial Disparities in Anemia and Mineral Metabolism Management?

    OpenAIRE

    Turenne, Marc N.; Cope, Elizabeth L.; Porenta, Shannon; Mukhopadhyay, Purna; Fuller, Douglas S.; Pearson, Jeffrey M.; Dahlerus, Claudia; Lantz, Brett; Tentori, Francesca; Robinson, Bruce M.

    2014-01-01

    Implementation of the Medicare ESRD prospective payment system (PPS) and changes to dosing guidelines for erythropoiesis-stimulating agents (ESAs) in 2011 appear to have influenced use of injectable medications among dialysis patients. Given historically higher ESA and vitamin D use among black patients, we assessed the effect of these policy changes on racial disparities in the management of anemia and mineral metabolism. Analyses used cross-sectional monthly cohorts for a period-prevalent s...

  17. Predictors of anemia in a multi-ethnic chronic kidney disease population: a case–control study

    OpenAIRE

    Lau, Bing Chang Vincent; Ong, Kheng Yong; Yap, Chun Wei; Vathsala, Anantharaman; How, Priscilla

    2015-01-01

    Anemia is a common complication of chronic kidney disease (CKD). However, risk factors of anemia in CKD patients in Singapore are not well established. Hence, a retrospective, case–control study involving non-dialysis CKD patients was conducted to determine possible predictors of anemia in the local CKD population. Non-dialysis adult CKD patients, not receiving renal replacement therapy or erythropoiesis-stimulating-agents were included. Parameters collected included demographics e.g. age, se...

  18. Darbepoietin-alfa has comparable erythropoietic stimulatory effects to recombinant erythropoietin whilst preserving the bone marrow microenvironment

    OpenAIRE

    Dewamitta, Sita R; Russell, Megan R.; Nandurkar, Harshal; Walkley, Carl R

    2013-01-01

    Erythropoiesis stimulating agents are widely used for the treatment of anemia. Recently, we reported erythroid expansion with impaired B lymphopoiesis and loss of trabecular bone in C57BL/6 mice following ten days of treatment with low-dose short acting recombinant human erythropoietin. We have assessed erythropoietin against longer-acting darbepoietin-alfa at a comparable erythroid stimulatory dosage regime. Darbepoietin-alfa and erythropoietin induced similar in vivo erythropoietic expansio...

  19. Ferric Citrate, an Iron-Based Phosphate Binder, Reduces Health Care Costs in Patients on Dialysis Based on Randomized Clinical Trial Data

    OpenAIRE

    Rodby, Roger A.; Umanath, Kausik; Niecestro, Robert; Christopher Bond, T.; Sika, Mohammed; Lewis, Julia; Dwyer, Jamie P.; . .

    2015-01-01

    Background Patients with end-stage renal disease (ESRD) require phosphate binders for hyperphosphatemia and erythropoiesis-stimulating agents (ESAs) and intravenous (IV) iron for anemia. Ferric citrate (FC) is a novel, iron-based phosphate binder that increases iron stores and decreases IV iron and ESA usage while maintaining hemoglobin levels, and may decrease the cost of ESRD care. The study objectives were to (1) quantify differences in ESA and IV iron usage among ESRD patients receiving F...

  20. Anemia of chronic kidney disease: Treat it, but not too aggressively.

    Science.gov (United States)

    Nakhoul, Georges; Simon, James F

    2016-08-01

    Anemia of renal disease is common and is associated with significant morbidity and death. It is mainly caused by a decrease in erythropoietin production in the kidneys and can be partially corrected with erythropoiesis-stimulating agents (ESAs). However, randomized controlled trials have shown that using ESAs to target normal hemoglobin levels can be harmful, and have called into question any benefits of ESA treatment other than avoidance of transfusions. PMID:27505883

  1. High-Throughput Screening of Small Molecules Identifies Hepcidin Antagonists

    OpenAIRE

    Fung, Eileen; Sugianto, Priscilla; Hsu, Jason; Damoiseaux, Robert; Ganz, Tomas; Nemeth, Elizabeta

    2013-01-01

    Anemia of inflammation (AI) is common in patients with infection, autoimmune diseases, cancer, and chronic kidney disease. Unless the underlying condition can be reversed, treatment options are limited to erythropoiesis-stimulating agents with or without intravenous iron therapy, modalities that are not always effective and can cause serious adverse effects. Hepcidin, the iron regulatory hormone, has been identified as a pathogenic factor in the development of AI. To explore new therapeutic o...

  2. Managing anemia in lymphoma and multiple myeloma

    OpenAIRE

    Gunnar Birgegård

    2008-01-01

    Gunnar BirgegårdDepartment of Haematology, University Hospital, Uppsala, SwedenAbstract: Anemia is common in cancer, and lymphoproliferative disease is no exception. Erythropoiesis-stimulating agents (ESA) have been used for renal anemia since 1986, and considerably later in cancer anemia. The first studies were published around 1993, but the use of ESA did not become common in cancer anemia until in the late 1990s. Cancer anemia is still under-treated. This review gives an overview...

  3. Assessment of Iron Status in Anemic Children with Chronic Kidney Disease

    OpenAIRE

    Ali K Alzahrani1, 2, Abdrahman Alzahrani3, Nihad A Al Nashar4 , Hala A Mohamed4

    2013-01-01

    Background: Iron deficiency is the commonest cause of resistance to erythropoiesis stimulating agents (ESAs) in dialyzed children treated from anemia of chronic kidney disease (CKD). Aim of the work: This study was conducted in order to evaluate the significance of different biomarkers in assessment of iron status during management of anemic children with CKD. Patients and method: Twenty five children with diagnosis of anemia of chronic kidney disease were enrolled for the study. They were cl...

  4. Thresholds of iron markers for iron deficiency erythropoiesis—finding of the Japanese nationwide dialysis registry

    OpenAIRE

    Hamano, Takayuki; Fujii, Naohiko; Hayashi, Terumasa; Yamamoto, Hiroyasu; Iseki, Kunitoshi; Tsubakihara, Yoshiharu

    2015-01-01

    Reportedly, serum ferritin levels are much lower in Japanese hemodialysis (HD) patients than their Western counterparts. Therefore, the cutoff values of ferritin and transferrin saturation (TSAT) for iron deficiency might differ from other countries. We conducted a cross-sectional observational study using the Japanese nationwide registry data. We enrolled 142,339 maintenance HD patients and assessed the association between these markers, hemoglobin (Hb), and erythropoiesis-stimulating agent ...

  5. Deep Brain Stimulation Tested for Early Alzheimer's

    Science.gov (United States)

    ... 160137.html Deep Brain Stimulation Tested for Early Alzheimer's Although treatment seems safe, benefit isn't yet ... brain stimulation appears safe for people with early Alzheimer's disease -- and might even slow down memory loss ...

  6. The role of aromatase inhibitors in ameliorating deleterious effects of ovarian stimulation on outcome of infertility treatment

    OpenAIRE

    Diamond Michael P; Casper Robert F; Mitwally Mohamed FM

    2005-01-01

    Abstract Clinical utilization of ovulation stimulation to facilitate the ability of a couple to conceive has not only provided a valuable therapeutic approach, but has also yielded extensive information on the physiology of ovarian follicular recruitment, endometrial receptivity and early embryo competency. One of the consequences of the use of fertility enhancing agents for ovarian stimulation has been the creation of a hyperestrogenic state, which may influence each of these parameters. Use...

  7. Ficus Deltoidea: A potential source for new oral antidiabetic agent

    International Nuclear Information System (INIS)

    Ficus deltoidea or locally known as Mas Cotek is one of the common medicinal plant used in Malaysia. Ethno botanical approaches showed that this plant possess antidiabetic property. Previous study had shown that F. deltoidea reduced hyperglycemia in type I diabetic rats at different prandial state. This study was done to elucidate the possible antihyperglycemic mechanisms of F. deltoidea. The results showed that F. deltoidea significantly stimulated insulin secretion from pancreatic β-cells with the highest magnitude of stimulation was 7.31-fold (p50 value was 4.15±0.25 mg/ml. Kinetic analysis of the enzyme activity revealed the F. deltoidea exhibited a mixed-type inhibition mechanism against sucrase activity. Such observations showed that F. deltoidea has the potential to be developed as new oral antidiabetic agent for the treatment of diabetes mellitus. (author)

  8. A wireless rechargeable implanted oscillating field stimulator

    OpenAIRE

    Guanghao Zhang; Suying Pan

    2010-01-01

    Oscillating field stimulation has been proved to be an effective method to induce the axonal regeneration after spinal cord injury. However, the primary batteries used in these stimulators provide limited energy, which restricts the operating life of the stimulator. This paper proposed a method of wireless recharging to prolong the time of treatment. Moreover, the size of the rechargeable battery is much smaller than the primary battery, and the dimension of the stimulator could be reduced to...

  9. Neuromuscular Electrical Stimulation for Skeletal Muscle Function

    OpenAIRE

    Doucet, Barbara M.; Lam, Amy; Griffin, Lisa

    2012-01-01

    Lack of neural innervation due to neurological damage renders muscle unable to produce force. Use of electrical stimulation is a medium in which investigators have tried to find a way to restore movement and the ability to perform activities of daily living. Different methods of applying electrical current to modify neuromuscular activity are electrical stimulation (ES), neuromuscular electrical stimulation (NMES), transcutaneous electrical nerve stimulation (TENS), and functional electrical ...

  10. Optimistic Agents are Asymptotically Optimal

    OpenAIRE

    Sunehag, Peter; Hutter, Marcus

    2012-01-01

    We use optimism to introduce generic asymptotically optimal reinforcement learning agents. They achieve, with an arbitrary finite or compact class of environments, asymptotically optimal behavior. Furthermore, in the finite deterministic case we provide finite error bounds.

  11. Agents containing chlorhexidine in dentistry

    OpenAIRE

    Lebedeva S.N.; Zemlyanichenko М.К.

    2011-01-01

    Aclinical definition of the efficacy of chlorhexidine-containing means for reducing the risk of dental caries and gingivitis with plastic caps. Chlorhexidine is an effective antimicrobial agent for the formation of individual programs for the prevention of dental caries

  12. Chemical Agents: Facts about Evacuation

    Science.gov (United States)

    ... Health Emergency Response Guide Reaching At-Risk Populations Chemical Agents: Facts About Evacuation Format: Select one PDF [ ... on Facebook Tweet Share Compartir Some kinds of chemical accidents or attacks, such as a train derailment ...

  13. Optical stimulator for vision-based sensors

    DEFF Research Database (Denmark)

    Rössler, Dirk; Pedersen, David Arge Klevang; Benn, Mathias;

    2014-01-01

    We have developed an optical stimulator system for vision-based sensors. The stimulator is an efficient tool for stimulating a camera during on-ground testing with scenes representative of spacecraft flights. Such scenes include starry sky, planetary objects, and other spacecraft. The optical...

  14. Geothermal Reservoir Well Stimulation Program: technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    Each of the following types of well stimulation techniques are summarized and explained: hydraulic fracturing; thermal; mechanical, jetting, and drainhole drilling; explosive and implosive; and injection methods. Current stimulation techniques, stimulation techniques for geothermal wells, areas of needed investigation, and engineering calculations for various techniques. (MHR)

  15. Electrical Stimulation Enhances Reinnervation After Nerve Injury

    OpenAIRE

    Willand, Michael P

    2015-01-01

    Electrical muscle stimulation following peripheral nerve injury has been a controversial method of treatment due primarily to the inconsistent literature surrounding it. In this presentation transcript I outline ongoing experiments investigating a clinically translatable daily muscle stimulation paradigm in rats following nerve injury. Results show that reinnervation of muscle and functional behavioural metrics are enhanced with daily stimulation with upregulation of intramuscular neurotrophi...

  16. PENETRATION ENHANCEMENT OF MEDICINAL AGENTS

    OpenAIRE

    Sharma Ganesh N.; Sanadya Jyotsana; Kaushik Avinash; Dwivedi Abha

    2012-01-01

    Many current therapeutic agents like antibiotics, ionizable and peptide drugs are impermeable or do not possess the requisite physicochemical properties for efficient transport through outer tissue barrier to attain therapeutic blood level. For this reason the delivery of such drugs through barriers is currently one of the major interests in pharmaceutical research. Penetration enhancers or promoters are agents that have no therapeutic properties of their own but can transport the sorption of...

  17. Agents in E-learning

    OpenAIRE

    S. Mencke; Dumke, R

    2007-01-01

    This paper presents a framework to describe thecrossover domain of e-learning and agent technology.Furthermore it is used to classify existing work and possiblestarting points for the future development of agenttechniques and technologies order to enhance theperformance and the effectiveness of several aspects of elearningsystems. Agents are not a new concept but their usein the field of e-learning constitutes a basis for consequentialadvances.

  18. Handling of injectable antineoplastic agents.

    OpenAIRE

    Knowles, R S; Virden, J E

    1980-01-01

    Although the clinical toxicity of antineoplastic drugs has been well documented there is little or no information on the problems that may arise on the handling and mishandling of such agents. This paper attempts to highlight the importance of taking precautions to prevent adverse effects resulting from contact with cytotoxic drugs during handling and to suggest a practical guide for the handling of such agents.

  19. Biocontrol agents in signalling resistance

    OpenAIRE

    Loon, L C; Pieterse, C.M.J.

    2002-01-01

    The mechanisms by which biological control agents suppress disease comprise competition for nutrients, notably iron, production of antibiotics, and secretion of lytic enzymes, as well as inducing resistance in the plant. The former three mechanisms act primarily on the pathogen by decreasing its activity, growth, and/or survival and require the biocontrol agent and the pathogen to be in close proximity. Because microorganisms with biocontrol properties and soilborne pathogens are both attract...

  20. Epidemic Spreading with External Agents

    OpenAIRE

    Banerjee, Siddhartha; Gopalan, Aditya; Das, Abhik Kumar; Shakkottai, Sanjay

    2012-01-01

    We study epidemic spreading processes in large networks, when the spread is assisted by a small number of external agents: infection sources with bounded spreading power, but whose movement is unrestricted vis-\\`a-vis the underlying network topology. For networks which are `spatially constrained', we show that the spread of infection can be significantly speeded up even by a few such external agents infecting randomly. Moreover, for general networks, we derive upper-bounds on the order of the...

  1. Locating Agents in RFID Architectures

    OpenAIRE

    Abdel-Naby, Sameh; Giorgini, Paolo

    2006-01-01

    The use of software agents can create an “intelligent” interface between users’ preferences and the back‐end systems. Agents are now able to interact and communicate with each other, forming a virtual community and feeding back the user with suggestions. Innovative systems related to Asset Tracking, Inventory and Shelving architectures are more often involving advanced communication techniques (e.g., RFID); these systems are responsible for user authentication and objects verification. RFID s...

  2. Towards Building Computational Agent Schemes

    Czech Academy of Sciences Publication Activity Database

    Beuster, Gerd; Krušina, Pavel; Neruda, Roman; Rydvan, Pavel

    Wien : SpringerVerlag, 2003 - (Pearson, D.; Steele, N.; Albrecht, R.), s. 210-215 ISBN 3-211-00743-1. [ICANNGA'2003 /6./. Roanne (FR), 23.04.2003-25.04.2003] R&D Projects: GA ČR GA201/02/0428 Institutional research plan: AV0Z1030915 Keywords : multi agent system s * intelligent agent s * hybrid models Subject RIV: BA - General Mathematics

  3. Cooperation of Computational Intelligence Agents

    Czech Academy of Sciences Publication Activity Database

    Neruda, Roman

    Los Alamitos : IEEE Computer Society, 2006 - (Smari, W.; McQuay, W.), s. 256-263 ISBN 0-9785699-0-3. [International Symposium on Collaborative Technologies and System s. Las Vegas (US), 14.05.2006-17.05.2006] R&D Projects: GA AV ČR(CZ) 1ET100300419 Institutional research plan: CEZ:AV0Z10300504 Keywords : multi - agent system s * cooperative agent s * computational intelligence * ontologies Subject RIV: IN - Informatics, Computer Science

  4. Bacteriocins as potential anticancer agents

    OpenAIRE

    Sukhraj eKaur; Sumanpreet eKaur

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have nonspecific toxicity towards normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeu...

  5. Bacteriocins as Potential Anticancer Agents

    OpenAIRE

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeu...

  6. Business Intelligence using Software Agents

    OpenAIRE

    Ana-Ramona BOLOGA; Razvan BOLOGA

    2011-01-01

    This paper presents some ideas about business intelligence today and the importance of developing real time business solutions. The authors make an exploration of links between business intelligence and artificial intelligence and focuses specifically on the implementation of software agents-based systems in business intelligence. There are briefly presented some of the few solutions proposed so far that use software agents properties for the benefit of business intelligence. The authors then...

  7. Electrical stimulation to optimize cardioprotective exosomes from cardiac stem cells.

    Science.gov (United States)

    Campbell, C R; Berman, A E; Weintraub, N L; Tang, Y L

    2016-03-01

    Injured or ischemic cardiac tissue has limited intrinsic capacity for regeneration. While stem cell transplantation is a promising approach to stimulating cardiac repair, its success in humans has thus far been limited. Harnessing the therapeutic benefits of stem cells requires a better understanding of their mechanisms of action and methods to optimize their function. Cardiac stem cells (CSC) represent a particularly effective cellular source for cardiac repair, and pre-conditioning CSC with electrical stimulation (EleS) was demonstrated to further enhance their function, although the mechanisms are unknown. Recent studies suggest that transplanted stem cells primarily exert their effects through communicating with endogenous tissues via the release of exosomes containing cardioprotective molecules such as miRNAs, which upon uptake by recipient cells may stimulate survival, proliferation, and angiogenesis. Exosomes are also effective therapeutic agents in isolation and may provide a feasible alternative to stem cell transplantation. We hypothesize that EleS enhances CSC-mediated cardiac repair through its beneficial effects on production of cardioprotective exosomes. Moreover, we hypothesize that the beneficial effects of biventricular pacing in patients with heart failure may in part result from EleS-induced preconditioning of endogenous CSC to promote cardiac repair. With future research, our hypothesis may provide applications to optimize stem cell therapy and augment current pacing protocols, which may significantly advance the treatment of patients with heart disease. PMID:26880625

  8. Redox-sensitive stimulation of type-1 ryanodine receptors by the scorpion toxin maurocalcine. : Redox-sensitive RyR stimulation by Maurocalcine

    OpenAIRE

    Ronjat, Michel; Finkelstein, José Pablo; Llanos, Paola; Montecinos, Luis; Bichraoui, Hicham; De Waard, Michel; Hidalgo, Cecilia; Bull, Ricardo

    2013-01-01

    The scorpion toxin maurocalcine acts as a high affinity agonist of the type-1 ryanodine receptor expressed in skeletal muscle. Here, we investigated the effects of the reducing agent dithiothreitol or the oxidizing reagent thimerosal on type-1 ryanodine receptor stimulation by maurocalcine. Maurocalcine addition to sarcoplasmic reticulum vesicles actively loaded with calcium elicited Ca(2+) release from native vesicles and from vesicles pre-incubated with dithiothreitol; thimerosal addition t...

  9. What makes virtual agents believable?

    Science.gov (United States)

    Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

    2016-01-01

    In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

  10. [A case of recurrent aseptic meningitis induced by ergot agents].

    Science.gov (United States)

    Ogawa, Tomoko; Tagawa, Asako; Hashimoto, Ritsuo; Kato, Hiroyuki

    2015-01-01

    We describe the case of a 29-year-old woman with recurrent aseptic meningitis that was caused by ergot agents. She miscarried at age 27, and the uterus constrictor methylergometrine was prescribed. Three days later, she developed aseptic meningitis and was hospitalized. Two years later, she again developed aseptic meningitis the day after she took ergotamine tartrate. In both events, her symptoms improved rapidly when the medication was stopped. The drug-induced lymphocyte stimulation test for methylergometrine yielded a value of 180%. Drug-induced meningitis is a rare form of recurrent aseptic meningitis. Many studies have reported cases of meningitis caused by non-steroidal anti-inflammatory drugs, but many other drugs can induce aseptic meningitis. To the best of our knowledge, this is the first case of aseptic meningitis induced by ergot agents. PMID:26103816

  11. Hypothalamic thermal stimulation modulates vasopressin release in hyperosmotically stimulated rabbits.

    Science.gov (United States)

    Keil, R; Gerstberger, R; Simon, E

    1994-10-01

    Under thermoneutral conditions conscious rabbits received systemic infusions of NaCl as hypertonic solution (90 mueq.min-1.kg body wt-1), which raised their plasma osmolality from 283 to 312 mosmol/kgH2O. Rabbits receiving isotonic saline served as controls. Hypertonic stimulation induced a 60% reduction of both respiratory frequency and evaporative water loss. Rectal temperature rose by 0.4 degrees C despite enhanced peripheral vasodilation as indicated by increased ear skin temperature. Plasma vasopressin (AVP), aldosterone (ALDO), and corticosterone (COR) were significantly elevated from 6 to 16 pg/ml, 90 to 180 pg/ml, and 17 to 40 ng/ml, respectively. To elucidate the importance of central temperature for AVP and adrenal corticosteroid release, hypothalamic thermal stimulations (20 min) were superimposed during established iso- and hyperosmotic steady-state conditions. Different from isosmotic controls, hyperosmotic animals responded to hypothalamic cooling (37 degrees C) with a significant decrease in plasma AVP from 16 to 13 pg/ml and to hypothalamic warming (41 degrees C) with a significant rise from 16 to 19 pg/ml. A weak temperature effect on COR release was also disclosed, especially of hypothalamic cooling, which significantly lowered plasma COR from 42 to 34 ng/ml. These results provide evidence for positive local temperature coefficients of hypothalamic control of AVP release and suggest a similar property also for the control of COR release by the hypothalamo-adenohypophysial axis. PMID:7943420

  12. 46 CFR Sec. 2 - General Agents' authority.

    Science.gov (United States)

    2010-10-01

    ... RESPONSIBILITY OF GENERAL AGENTS TO UNDERTAKE EMERGENCY REPAIRS IN FOREIGN PORTS Sec. 2 General Agents' authority. The General Agents are hereby delegated authority to undertake for the account of the...

  13. Brain stimulation and inhibitory control.

    Science.gov (United States)

    Juan, Chi-Hung; Muggleton, Neil G

    2012-04-01

    Inhibitory control mechanisms are important in a range of behaviours to prevent execution of motor acts which, having been planned, are no longer necessary or appropriate. Examples of this can be seen in a range of sports, such as cricket and baseball, where the choice between execution and inhibition of a bat swing must be made in a very brief time window. Deficits in inhibitory control have been associated with problems in behavioural regulation in impulsive violence as well as a range of clinical disorders. The roles of various areas, including the frontal eye fields (FEF), the pre-supplementary motor area (pre-SMA) and the inferior frontal gyrus, in inhibitory control have been investigated using an inhibitory control task and both transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). Typically effects on response inhibition but no effects on response generation have been seen. The contributions of these areas to performance seem to differ with, for example, pre-SMA being involved when the task is relatively novel whereas this is not the case for FEF. The findings from brain stimulation studies offer both insight into which areas are necessary for effective inhibitory control and recent extension of findings for the role of the inferior frontal gyrus illustrate how the specific functions by which these areas contribute may be further clarified. Future work, including making use of the temporal specificity of TMS and combination of TMS/tDCS with other neuroimaging techniques, may further clarify the nature and functions played by the network of areas involved in inhibitory control. PMID:22494830

  14. Multichannel magnetic stimulation system design considering mutual couplings among the stimulation coils.

    Science.gov (United States)

    Han, Byung H; Chun, In K; Lee, Sang C; Lee, Soo Y

    2004-05-01

    We introduce some simulation and experiment results of the multichannel magnetic stimulator development that has been carried out as an initial attempt to realize a multichannel functional magnetic stimulator. For efficient functional magnetic stimulations, precise spatial localization of stimulation sites without any movements of the stimulation coils is very important. We have found that the mutual coupling effect among the adjacent stimulation coils in the coil array has to be considered in the determination of the charge voltages in some coil array configurations. Experimental results obtained with a 4-channel magnetic stimulator are presented. PMID:15132507

  15. Geo-Agents: Design and Implement

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Geo-Agents, a multi-agent system that processes distr ib utedgeospatial information and geospatial service was presented. Firstly, the requirement for distributed geographical information process was discussed, and the architecture of Geo-Agents was introduced. Then in-depth discussions were r aised on agent system implementation, such as the basic agent, agent advertising , message passing, and collaborating. An example was also given to explain the p roblem solving process.

  16. Special issue about advances in Physical Agents

    OpenAIRE

    Cazorla Quevedo, Miguel Ángel; Matellán Olivera, Vicente

    2011-01-01

    Nowadays, there are a lot of Spanish groups which are doing research in areas related with physical agents: they use agent-based technologies concepts, especially industrial applications, robotics and domotics (physical agents) and applications related to the information society, (software agents) highlighting the similarities and synergies among physical and software agents. In this special issue we will show several works from those groups, focusing on the recent advances in Physical Agents.

  17. Learning by Observation of Agent Software Images

    OpenAIRE

    Costa, Paulo Roberto; Botelho, Luís Miguel

    2014-01-01

    Learning by observation can be of key importance whenever agents sharing similar features want to learn from each other. This paper presents an agent architecture that enables software agents to learn by direct observation of the actions executed by expert agents while they are performing a task. This is possible because the proposed architecture displays information that is essential for observation, making it possible for software agents to observe each other. The agent architecture support...

  18. Erythropoietin stimulating agents in the management of anemia of chronic kidney disease

    OpenAIRE

    Hayat, Amir; Haria, Dhiren; Salifu, Moro O

    2008-01-01

    Anemia is a very common clinical problem in patients with chronic kidney disease (CKD) and is associated with increased morbidity and mortality in these patients. Erythropoietin is a hormone synthesized in the kidney responsible for red blood cell maturation in the bone marrow. It is deficient in the majority of patients with advanced kidney disease thereby predisposing to anemia. Since the approval of recombinant human erythropoietin (epoetin alfa) by the US FDA in 1989, epoetin alfa and sim...

  19. Erythropoietin stimulating agents in the management of anemia of chronic kidney disease

    OpenAIRE

    Salifu, Moro O

    2008-01-01

    Amir Hayat, Dhiren Haria, Moro O SalifuDivision of Nephrology, Department of Medicine, SUNY Downstate Medical Center, Brooklyn, NY, USAAbstract: Anemia is a very common clinical problem in patients with chronic kidney disease (CKD) and is associated with increased morbidity and mortality in these patients. Erythropoietin is a hormone synthesized in the kidney responsible for red blood cell maturation in the bone marrow. It is deficient in the majority of patients with advanced kidney disease ...

  20. G-CSF: From granulopoietic stimulant to bone marrow stem cell mobilizing agent.

    Science.gov (United States)

    Bendall, Linda J; Bradstock, Kenneth F

    2014-08-01

    G-CSF was among the first cytokines to be identified and rapidly transitioned into clinical medicine. Initially used to promote the production of neutrophils in patients with chemotherapy-induced neutropenia it helped to revolutionize the delivery of cancer therapy. Its ability to mobilize hematopoietic stem cells from the bone marrow into the blood was subsequently exploited, changing the face of hematopoietic stem cell transplantation. Today the knowledge gained in unraveling the mechanisms of stem cell mobilization by G-CSF is being explored as a means to increase chemosensitivity in hematological malignancies. This review provides a brief history of G-CSF and then focuses on recent advances in our understanding of G-CSF-induced stem cell mobilization and the potential clinical application of this knowledge in chemo-sensitization. PMID:25131807

  1. Detection of nerve agent stimulants based on photoluminescent porous silicon interferometer

    OpenAIRE

    Kim, Seongwoong; Cho, Bomin; Sohn, Honglae

    2012-01-01

    Porous silicon (PSi) exhibiting dual optical properties, both Fabry-Pérot fringe and photolumincence, was developed and used as chemical sensors. PSi samples were prepared by an electrochemical etch of p-type silicon under the illumination of 300-W tungsten lamp during the etch process. The surface of PSi was characterized by cold field-emission scanning electron microscope. PSi samples exhibited a strong visible orange photoluminescence at 610 nm with an excitation wavelength of 460 nm as we...

  2. BEBIDAS ENERGIZANTES: ¿HIDRATANTES O ESTIMULANTES? Energy drinks: rehydrating agents or stimulants?

    OpenAIRE

    Miguel Cote-Menéndez; Claudia Ximena Rangel-Garzón; Marlib Yolima Sánchez-Torres; Adalbeis Medina-Lemus

    2011-01-01

    Antecedentes. Las bebidas energizantes tienen amplia distribución, su consumo ha aumentado debido al fácil acceso, sus propiedades estimulantes y a las características de inocuidad que se les atribuyen. El poco conocimiento de sus características lleva a confusión con las bebidas hidratantes usándolas de forma indiscriminada, aunque las bebidas hidratantes buscan prevenir la deshidratación y las energizantes tienen un efecto estimulante. Objetivo. Describir los componentes de las bebidas ener...

  3. Opiate withdrawal behavior after focal brain stimulation.

    Science.gov (United States)

    Williams, D A; Thorn, B E

    1984-11-01

    Electrical stimulation of the brainstem abolishes pain, while continued stimulation induces tolerance to the analgesic effect. Analgesic drugs producing tolerance also induce physical dependence, suggesting that the phenomenon of tolerance is associated with addiction. There is evidence that the neural mechanism for stimulation-produced analgesia is related to the release of opiate substances within the brain. We therefore propose that repeated or protracted brain stimulation elicits dependence upon the endorphins released by electrical stimulation of the neurons themselves. To investigate this possibility, rats were given repetitive bursts of analgesic electrical brain stimulation for two hours. Immediately thereafter, they were injected with the opiate antagonist, naloxone. Behaviors associated with low grade opiate withdrawal were observed. These data suggest that prolonged analgesic stimulation can result in naloxone-precipitated behaviors similar to the behaviors exhibited during opiate withdrawal. PMID:6542676

  4. Stimulated emission from NV centres in diamond

    CERN Document Server

    Jeske, Jan; McGuinness, Liam P; Reineck, Philip; Johnson, Brett C; McCallum, Jeffrey C; Jelezko, Fedor; Volz, Thomas; Cole, Jared H; Gibson, Brant C; Greentree, Andrew D

    2016-01-01

    Stimulated emission is the process fundamental to laser operation, thereby producing coherent photon output. Despite negatively-charged nitrogen-vacancy (NV$^-$) centres being discussed as a potential laser medium since the 1980's, there have been no definitive observations of stimulated emission from ensembles of NV$^-$ to date. Reasons for this lack of demonstration include the short excited state lifetime and the occurrence of photo-ionisation to the neutral charge state by light around the zero-phonon line. Here we show both theoretical and experimental evidence for stimulated emission from NV$^-$ states using light in the phonon-sidebands. Our system uses a continuous wave pump laser at 532 nm and a pulsed stimulating laser that is swept across the phononic sidebands of the NV$^-$. Optimal stimulated emission is demonstrated in the vicinity of the three-phonon line at 700 nm. Furthermore, we show the transition from stimulated emission to photoionisation as the stimulating laser wavelength is reduced fro...

  5. Colitis associated with biological agents

    Directory of Open Access Journals (Sweden)

    Hugh James Freeman

    2012-01-01

    Full Text Available In the past, there has been considerable focus on a host of drugs and chemicals that may produce colonic toxicity. Now, a variety of new biological monoclonal antibody agents, usually administered by infusion, have appeared in the clinical realm over the last decade or so to treat different chronic inflammatory or malignant disorders.For some of these agents, adverse effects have been documented, including apparently new forms of immune-mediated inflammatory bowel disease. In some, only limited symptoms have been recorded, but in others, severe colitis with serious complications, such as bowel perforation has been recorded. In others, adverse effects may have a direct vascular or ischemic basis, while other intestinal effects may be related to a superimposed infection. Some new onset cases of ulcerative colitis or Crohn’s disease may also be attributed to the same agents used to treat these diseases, or be responsible for disease exacerbation. Dramatic and well documented side effects have been observed with ipilimumab, a humanized monoclonal antibody developed to reduce and overcome cytotoxic T-lymphocyte antigen 4, a key negative feedback regulator of the T-cell anti-tumor response. This agent has frequently been used in the treatment of different malignancies, notably, malignant melanoma. Side effects with this agent occur in up to 40% and these are believed to be largely immune-mediated. One of these is a form of enterocolitis that may be severe, and occasionally, fatal. Other agents include rituximab (an anti-CD20 monoclonal antibody, bevacizumab (a monoclonal antibody against the vascular endothelial growth factor and anti-tumor necrosis factor agents, including infliximab, adalimumab and etanercept.

  6. Agent 2003 Conference on Challenges in Social Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Margaret Clemmons, ed.

    2003-01-01

    difficult social issues. Among the resources that give us the prospect of success is the innovative and transdisciplinary research community being built. We believe that Agent 2003 contributes to further progress in computational modeling of social processes, and we hope that you find these Proceedings to be stimulating and rewarding. As the horizons of this transdiscipline continue to emerge and converge, we hope to provide similar forums that will promote development of agent simulation modeling in the years to come.

  7. Development of secreted proteins as biotherapeutic agents.

    Science.gov (United States)

    Bonin-Debs, Angelika L; Boche, Irene; Gille, Hendrik; Brinkmann, Ulrich

    2004-04-01

    As one of the most important classes of proteins, secreted factors account for about one-tenth of the human genome, 3000 - 4000 in total, including factors of signalling pathways, blood coagulation and immune defence, as well as digestive enzymes and components of the extracellular matrix. Secreted proteins are a rich source of new therapeutics and drug targets, and are currently the focus of major drug discovery programmes throughout the industry. Many of the most important novel drugs developed in biotechnology have resulted from the application of secreted proteins as therapeutics. Secreted proteins often circulate throughout the body and, therefore, have access to most organs and tissues. Because of that, many of the factors are themselves therapeutic agents. This paper gives an overview on the features and functions of human secreted proteins and peptides, as well as strategies by which to discover additional therapeutic proteins from the human 'secretome'. Furthermore, a variety of examples are provided for the therapeutic use of recombinant secreted proteins as 'biologicals', including features and applications of recombinant antibodies, erythropoietin, insulin, interferon, plasminogen activators, growth hormone and colony-stimulating factors. PMID:15102604

  8. Primitive and definitive erythropoiesis in mammals

    OpenAIRE

    Palis, James

    2014-01-01

    Red blood cells (RBCs), which constitute the most abundant cell type in the body, come in two distinct flavors- primitive and definitive. Definitive RBCs in mammals circulate as smaller, anucleate cells during fetal and postnatal life, while primitive RBCs circulate transiently in the early embryo as large, nucleated cells before ultimately enucleating. Both cell types are formed from lineage-committed progenitors that generate a series of morphologically identifiable precursors that enucleat...

  9. A multi-agent architecture for geosimulation of moving agents

    Science.gov (United States)

    Vahidnia, Mohammad H.; Alesheikh, Ali A.; Alavipanah, Seyed Kazem

    2015-10-01

    In this paper, a novel architecture is proposed in which an axiomatic derivation system in the form of first-order logic facilitates declarative explanation and spatial reasoning. Simulation of environmental perception and interaction between autonomous agents is designed with a geographic belief-desire-intention and a request-inform-query model. The architecture has a complementary quantitative component that supports collaborative planning based on the concept of equilibrium and game theory. This new architecture presents a departure from current best practices geographic agent-based modelling. Implementation tasks are discussed in some detail, as well as scenarios for fleet management and disaster management.

  10. Thermally stimulated luminescence in polycarbonate

    International Nuclear Information System (INIS)

    Thermally stimulated luminescence (TSL) in gamma-irradiated polycarbonate (PC) has been investigated, in the temperature range from room temperature to the melting point of the material. Two glow peaks, designated as P1 and P2 respectively, are observed at 420 K and 438 K. The intensity of glow peak P1 is found to decrease gradually; and glow peak maximum is found to shift towards lower temperatures with dose of irradiation. The intensity of glow peak P2, increases gradually at first up to a certain dose, above which the intensity gradually falls with dose of irradiation; the position of the maximum of this peak remains the same. The glow peak P1 is attributed to the detrapping facilitated by the large scale macromolecular motions on thermal stimulation around the glass transition temperature (Tg) of polycarbonate. This assignment is in good agreement with the dielectric, mechanical loss measurements near the Tg of the polymer. The shift of peak P1 towards lower temperatures, indicate a decrease in Tg, in consequence to a decrease in molecular weight; with increase in the dose of irradiation. The dose dependence of the glow peak P2, indicates the cross-linking of the polyenyl type free radicals formed on irradiation of PC. Analysis of the glow peaks and the mechanism of TSL are discussed. (author). 13 refs., 1 fig., 1 tab

  11. Braille line using electrical stimulation

    International Nuclear Information System (INIS)

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards

  12. Braille line using electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Puertas, A; Pures, P; Echenique, A M; Ensinck, J P Graffigna y G [Gabinete de TecnologIa Medica. Universidad N. de San Juan (Argentina)

    2007-11-15

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  13. Neonate intestinal immune response to CpG oligodeoxynucleotide stimulation.

    Directory of Open Access Journals (Sweden)

    Sonia Lacroix-Lamandé

    Full Text Available BACKGROUND: The development of mucosal vaccines is crucial to efficiently control infectious agents for which mucosae are the primary site of entry. Major drawbacks of these protective strategies are the lack of effective mucosal adjuvant. Synthetic oligodeoxynucleotides that contain several unmethylated cytosine-guanine dinucleotide (CpG-ODN motifs are now recognized as promising adjuvants displaying mucosal adjuvant activity through direct activation of TLR9-expressing cells. However, little is known about the efficacy of these molecules in stimulating the intestinal immune system in neonates. METHODOLOGY/PRINCIPAL FINDINGS: First, newborn mice received CpG-ODN orally, and the intestinal cytokine and chemokine response was measured. We observed that oral administration of CpG-ODN induces CXC and CC chemokine responses and a cellular infiltration in the intestine of neonates as detected by immunohistochemistry. We next compared the efficiency of the oral route to intraperitoneal administration in stimulating the intestinal immune responses of both adults and neonates. Neonates were more responsive to TLR9-stimulation than adults whatever the CpG-ODN administration route. Their intestinal epithelial cells (IECs indirectly responded to TLR9 stimulation and contributed to the CXC chemokine response, whereas other TLR9-bearing cells of the lamina-propria produced CC chemokines and Th1-type cytokines. Moreover, we showed that the intestine of adult exhibited a significantly higher level of IL10 at homeostasis than neonates, which might be responsible for the unresponsiveness to TLR9-stimulation, as confirmed by our findings in IL10-deficient mice. CONCLUSIONS/SIGNIFICANCE: This is the first report that deciphers the role played by CpG-ODN in the intestine of neonates. This work clearly demonstrates that an intraperitoneal administration of CpG-ODN is more efficient in neonates than in adults to stimulate an intestinal chemokine response due to their

  14. Sensors for detecting biological agents

    Directory of Open Access Journals (Sweden)

    Kim E. Sapsford

    2008-03-01

    Full Text Available Biological agents including viruses, bacteria, and other naturally occurring pathogenic organisms, along with the toxins they produce, are considered far harder to detect and defend against than chemical agents. Here we provide an overview of the predominant molecular sensing technologies for the detection of these agents. This includes biosensing strategies based upon use of antibodies, genomic analysis, biochemical testing, other recognition interactions, and cellular-based responses. We survey some popular sensing approaches, illustrate them with current examples showing how they have been applied, and discuss their intrinsic benefits and potential liabilities. Lastly, within the context of security applications, some approaches for integrating sensing technologies into field-portable devices are discussed.

  15. Agent review phase one report.

    Energy Technology Data Exchange (ETDEWEB)

    Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell

    2009-12-01

    This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.

  16. Dopamine agents for hepatic encephalopathy

    DEFF Research Database (Denmark)

    Junker, Anders Ellekær; Als-Nielsen, Bodil; Gluud, Christian;

    2014-01-01

    BACKGROUND: Patients with hepatic encephalopathy may present with extrapyramidal symptoms and changes in basal ganglia. These changes are similar to those seen in patients with Parkinson's disease. Dopamine agents (such as bromocriptine and levodopa, used for patients with Parkinson's disease) have...... therefore been assessed as a potential treatment for patients with hepatic encephalopathy. OBJECTIVES: To evaluate the beneficial and harmful effects of dopamine agents versus placebo or no intervention for patients with hepatic encephalopathy. SEARCH METHODS: Trials were identified through the Cochrane...... the trials followed participants after the end of treatment. Only one trial reported adequate bias control; the remaining four trials were considered to have high risk of bias. Random-effects model meta-analyses showed that dopamine agents had no beneficial or detrimental effect on hepatic...

  17. Multi-Agent Software Engineering

    International Nuclear Information System (INIS)

    This paper proposed an alarm-monitoring system for people based on multi-agent using maps. The system monitors the users physical context using their mobile phone. The agents on the mobile phones are responsible for collecting, processing and sending data to the server. They can determine the parameters of their environment by sensors. The data are processed and sent to the server. On the other side, a set of agents on server can store this data and check the preconditions of the restrictions associated with the user, in order to trigger the appropriate alarms. These alarms are sent not only to the user who is alarmed to avoid the appeared restriction, but also to his supervisor. The proposed system is a general purpose alarm system that can be used in different critical application areas. It has been applied for monitoring the workers of radiation sites. However, these workers can do their activity tasks in the radiation environments safely

  18. Monitoring presence of chemical agents

    International Nuclear Information System (INIS)

    The specification describes a case for use with a hand-portable chemical agent detector for continuously monitoring an atmosphere for the presence of predetermined chemical agents. The detector having means for ionizing air samples and providing at an output terminal electrical signals representative of the mobility spectrum of ionized chemical vapours produced by the ionizing means. The case comprises means for defining a chamber in the case for supporting and removably enclosing the detector, means for communicating ambient atmosphere to the chamber, electrical circuit means in the case, the circuit means being adapted to be detachably connected to the detector output terminal when the detector is positioned in the chamber and being responsive to the electrical signals for producing an alarm signal when the signals detect a chemical agent concentration in the atmosphere exceeding a predetermined concentration level, and alarm means responsive to the alarm signal. (author)

  19. [Effect of stimulation of the tooth pulp on gastrointestinal motility in rabbits].

    Science.gov (United States)

    Nando, R

    1983-04-01

    Effects of electrical stimulation of the inciser tooth pulp on the gastrointestinal motility were investigated in the rabbit anesthetized with urethane and chloralose. Pulpal Stimulation caused an excitatory or an inhibitory effect in the gastric body and antrum and the ducodenum. After bilateral splanchnicotomy the excitatory response to the pulpal stimulation was reinforced or the inhibitory response converted to the excitatory response. An additional cervical vagotomy abolished the excitatory and inhibitory response. Atropine diminished the spontaneous efferent discharges of vagal gastric branch (VGB) and abolished the excitatory and inhibitory response to stimulation of the pulp and the inferior alveolar nerve. This agent also blocked the potentials of the VGB evoked by afferent stimulation of the inferior aveolar nerve. Hexamethonium bromide abolished the excitatory and inhibitory responses to the pulpal stimulation but did not affect spontaneous discharges and increased discharges of the VGB to pulpal stimulation. Morphine produced decreased rate of the spontaneous discharge of the VGB and abolished increased rate of discharges of the VGB as well as the gastrointestinal responses to pulpal stimulation. It is concluded from these results that the afferent impulses caused by pulpal stimulation and the inferior alveolar nerve 'reflex'ly activate the vagal motor nuclei in the medulla oblongata and the sympathetic splanchnic nuclei in the thoracic segments through the trigeminal nerve: The vagus nerves produced the excitatory response in the gastrointestinal motility, while the splanchnic nerves caused the inhibitory response. It was supposed that sites of action of atropine and morphine is not in peripheral site, but in the central nerves site. PMID:6663937

  20. Suppressive effects of co-stimulatory molecule expressions on mouse splenocytes by anti-allergic agents in vitro

    Directory of Open Access Journals (Sweden)

    Jun-ichi Ito

    2000-01-01

    Full Text Available The influence of anti-allergic drugs, epinastine hydrochloride (EP and disodium cromoglycate (DSCG, on the co-stimulatory molecule expression was examined using in vitro cell culture technique. Spleen cells obtained from BALB/c mice 10 days after immunization with haemocyanin absorbed to aluminium hydroxide were cultured in the presence of 100.0 μg/ml haemocyanin and various concentrations of the agents. Low concentrations (< 1.5 2 10-4 M of EP and DSCG did not influence spleen cell blastic activity induced by antigenic stimulation, whereas these agents caused significant inhibition of spleen cell activation when 2 × 10-4 M of the agents were added to cell cultures. EP and DSCG also did not affect blastic activity of sensitized splenic T cells by anti-CD3 monoclonal antibody stimulation even when these cells were cultured in the presence of 2 × 10-4 M of the agents. We next examined the influence of EP and DSCG on the expression of co-stimulatory molecules on spleen cells in response to antigenic stimulation. Sensitized spleen cells were cultured in the presence of 2 × 10-4 M of the agents and the expression of molecules were examined by flow cytometer 24 h later. EP and DSCG suppressed the expression of costimulatory molecules, CD40 and CD80, but not CD86, on splenic B cells which were enhanced by antigenic stimulation in vitro.

  1. Suppressive effects of co-stimulatory molecule expressions on mouse splenocytes by anti-allergic agents in vitro.

    Science.gov (United States)

    Ito, J; Asano, K; Tryka, E; Kanai, K; Yamamoto, S; Hisamitsu, T; Suzaki, H

    2000-01-01

    The influence of anti-allergic drugs, epinastine hydrochloride (EP) and disodium cromoglycate (DSCG), on the co-stimulatory molecule expression was examined using in vitro cell culture technique. Spleen cells obtained from BALB/c mice 10 days after immunization with haemocyanin absorbed to aluminium hydroxide were cultured in the presence of 100.0 microg/ml haemocyanin and various concentrations of the agents. Low concentrations (DSCG did not influence spleen cell blastic activity induced by antigenic stimulation, whereas these agents caused significant inhibition of spleen cell activation when 2 x 10(-4) M of the agents were added to cell cultures. EP and DSCG also did not affect blastic activity of sensitized splenic T cells by anti-CD3 monoclonal antibody stimulation even when these cells were cultured in the presence of 2 x 10(-4) M of the agents. We next examined the influence of EP and DSCG on the expression of co-stimulatory molecules on spleen cells in response to antigenic stimulation. Sensitized spleen cells were cultured in the presence of 2 x 10(-4)M of the agents and the expression of molecules were examined by flow cytometer 24h later. EP and DSCG suppressed the expression of costimulatory molecules, CD40 and CD80, but not CD86, on splenic B cells which were enhanced by antigenic stimulation in vitro. PMID:10958379

  2. Autonomous sensor manager agents (ASMA)

    Science.gov (United States)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  3. An overview of inotropic agents.

    Science.gov (United States)

    Vroom, Margreeth B

    2006-09-01

    The use of inotropic agents has been surrounded by many controversies. Recent guidelines for the treatment of patients with chronic and acute heart failure have elucidated some of the issues, but many remain. As a result, a substantial variability in the use of agents between institutions and caregivers remains, which mainly results from the lack of uniform data in the literature. Prospective randomized trials with a long-term follow-up and sufficient power are clearly needed, and a number of trials are currently in progress. PMID:16959760

  4. Multisensory stimulation in stroke rehabilitation

    Directory of Open Access Journals (Sweden)

    Barbro Birgitta Johansson

    2012-04-01

    Full Text Available The brain has a large capacity for automatic simultaneous processing and integration of sensory information. Combining information from different sensory modalities facilitates our ability to detect, discriminate, and recognize sensory stimuli, and learning is often optimal in a multisensory environment. Currently used multisensory stimulation methods in stroke rehabilitation include motor imagery, action observation, training with a mirror or in a virtual environment, or various kinds of music therapy. Several studies have shown positive effects been reported but to give general recommendation more studies are needed. Patient heterogeneity and the interactions of age, gender, genes and environment are discussed. Randomized controlled longitudinal trials starting earlier post stroke are needed. The advance in brain network science and neuroimaging enabling longitudinal studies of structural and functional networks are likely to have an important impact on patient selection for specific interventions in future stroke rehabilitation.

  5. Acupuncture stimulation and neuroendocrine regulation.

    Science.gov (United States)

    Yu, Jung-Sheng; Zeng, Bai-Yun; Hsieh, Ching-Liang

    2013-01-01

    Acupuncture has been used to treat different conditions for at least 3000 years in China and has gained increasing acceptance worldwide. The acupuncture needle inserted into the muscle layer at the acupoint produces the so-called obtaining qi sensation that causes the excitation of A-δ and C-fibers of the muscle tissue, resulting in afferent signals. The afferent signals pass through the dorsal horn cells of the spinal cord ascending to the brain, such as the hypothalamus, enhancing the release of neuropeptides and hormones, and these afferent signals in the spinal segment may innervate the visceral organ, inducing effect on visceral function. Here, we reviewed the effect of acupuncture stimulation on neuropeptides and hormones, including β-endorphin, serotonin, oxytocin, adrenocorticotropic hormone, gonadotropin-releasing hormone, corticotrophin-releasing hormone, cholecystokinin, and acetylcholine, as well as insulin sensitivity, immunomodulation (anti-inflammation), and autonomic nerve activity. PMID:24215920

  6. Electrode array for neural stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Wessendorf, Kurt O. (Albuquerque, NM); Okandan, Murat (Edgewood, NM); Stein, David J. (Albuquerque, NM); Yang, Pin (Albuquerque, NM); Cesarano, III, Joseph (Albuquerque, NM); Dellinger, Jennifer (Albuquerque, NM)

    2011-08-16

    An electrode array for neural stimulation is disclosed which has particular applications for use in a retinal prosthesis. The electrode array can be formed as a hermetically-sealed two-part ceramic package which includes an electronic circuit such as a demultiplexer circuit encapsulated therein. A relatively large number (up to 1000 or more) of individually-addressable electrodes are provided on a curved surface of a ceramic base portion the electrode array, while a much smaller number of electrical connections are provided on a ceramic lid of the electrode array. The base and lid can be attached using a metal-to-metal seal formed by laser brazing. Electrical connections to the electrode array can be provided by a flexible ribbon cable which can also be used to secure the electrode array in place.

  7. Building Multi-Agent Systems Using Jason

    DEFF Research Database (Denmark)

    Boss, Niklas Skamriis; Jensen, Andreas Schmidt; Villadsen, Jørgen

    2010-01-01

    Technical University of Denmark (DTU). A part of this course was a short introduction to the multi-agent framework Jason, which is an interpreter for AgentSpeak, an agent-oriented programming language. As the final project in this course a solution to the Multi-Agent Programming Contest from 2007, the Gold...

  8. Transcranial electrical stimulation accelerates human sleep homeostasis.

    Directory of Open Access Journals (Sweden)

    Davide Reato

    Full Text Available The sleeping brain exhibits characteristic slow-wave activity which decays over the course of the night. This decay is thought to result from homeostatic synaptic downscaling. Transcranial electrical stimulation can entrain slow-wave oscillations (SWO in the human electro-encephalogram (EEG. A computational model of the underlying mechanism predicts that firing rates are predominantly increased during stimulation. Assuming that synaptic homeostasis is driven by average firing rates, we expected an acceleration of synaptic downscaling during stimulation, which is compensated by a reduced drive after stimulation. We show that 25 minutes of transcranial electrical stimulation, as predicted, reduced the decay of SWO in the remainder of the night. Anatomically accurate simulations of the field intensities on human cortex precisely matched the effect size in different EEG electrodes. Together these results suggest a mechanistic link between electrical stimulation and accelerated synaptic homeostasis in human sleep.

  9. A Chip for an Implantable Neural Stimulator

    DEFF Research Database (Denmark)

    Gudnason, Gunnar; Bruun, Erik; Haugland, Morten

    2000-01-01

    This paper describes a chip for a multichannel neural stimulator for functional electrical stimulation (FES). The purpose of FES is to restore muscular control in disabled patients. The chip performs all the signal processing required in an implanted neural stimulator. The power and digital data...... transmission to the stimulator passes through a 5 MHz inductive link. From the signals transmitted to the stimulator, the chip is able to generate charge-balanced current pulses with a controllable length up to 256 µs and an amplitude up to 2 mA, for stimulation of nerve fibers. The quiescent current...... consumption of the chip is approx. 650 µA at supply voltages of 6–12 V, and its size is 3.9×3.5 mm2. It has 4 output channels for use in a multipolar cuff electrode....

  10. Using Agent to Coordinate Web Services

    CERN Document Server

    Liu, C H; Chen, Jason J Y

    2009-01-01

    Traditionally, agent and web service are two separate research areas. We figure that, through agent communication, agent is suitable to coordinate web services. However, there exist agent communication problems due to the lack of uniform, cross-platform vocabulary. Fortunately, ontology defines a vocabulary. We thus propose a new agent communication layer and present the web ontology language (OWL)-based operational ontologies that provides a declarative description. It can be accessed by various engines to facilitate agent communication. Further, in our operational ontologies, we define the mental attitudes of agents that can be shared among other agents. Our architecture enhanced the 3APL agent platform, and it is implemented as an agent communication framework. Finally, we extended the framework to be compatible with the web ontology language for service (OWL-S), and then develop a movie recommendation system with four OWL-S semantic web services on the framework. The benefits of this work are: 1) dynamic ...

  11. Motivation-stimulating Strategies in English Classes

    Institute of Scientific and Technical Information of China (English)

    李宁

    2015-01-01

    Motivation plays a very important role in foreign language learning. So it becomes worthwhile to study the teachers’ motivation-stimulating strategies. This article mainly discusses two strategies of stimulating the students’motivation in English classes:environment-providing strategies and goal-oriented strategies. They are hoped to provide some references for English teachers to stimulate the students’learning motivation in their classes.

  12. What galvanic vestibular stimulation actually activates

    OpenAIRE

    IanSCurthoys

    2012-01-01

    In a recent paper in Frontiers Cohen et al. (2012) asked “What does galvanic vestibular stimulation actually activate?” and concluded that galvanic vestibular stimulation (GVS) causes predominantly otolithic behavioural responses. In this Perspective paper we show that such a conclusion does not follow from the evidence. The evidence from neurophysiology is very clear: galvanic stimulation activates primary otolithic neurons as well as primary semicircular canal neurons (Kim and Curthoys,...

  13. Electrodes for transcutaneous (surface) electrical stimulation

    OpenAIRE

    Keller Thierry; Kuhn Andreas

    2008-01-01

    In therapeutic and functional applications transcutaneous electrical stimulation (TES) is still the most frequently applied technique for muscle and nerve activation despite the huge efforts made to improve implantable technologies. Stimulation electrodes play the important role in interfacing the tissue with the stimulation unit. Between the electrode and the excitable tissue there are a number of obstacles in form of tissue resistivities and permittivities that can only be circumvented by m...

  14. Development of Receiver Stimulator for Auditory Prosthesis

    OpenAIRE

    K. Raja Kumar; P. Seetha Ramaiah

    2010-01-01

    The Auditory Prosthesis (AP) is an electronic device that can provide hearing sensations to people who are profoundly deaf by stimulating the auditory nerve via an array of electrodes with an electric current allowing them to understand the speech. The AP system consists of two hardware functional units such as Body Worn Speech Processor (BWSP) and Receiver Stimulator. The prototype model of Receiver Stimulator for Auditory Prosthesis (RSAP) consists of Speech Data Decoder, DAC, ADC, constant...

  15. Communication between osteoblasts stimulated by electromagnetic fields

    Institute of Scientific and Technical Information of China (English)

    ZHANG JianBao; ZHANG XiaoJun

    2007-01-01

    Pulsed electromagnetic field can affect the proliferation of osteoblasts, but the mechanism is obscure yet. The communication between osteoblasts, isolated from calvaria bone of newborn SD rats and stimulated with the rectangular electromagnetic field of 15 Hz and 4 mT, was studied. Our results showed that the osteoblasts radiated a kind of light after they were stimulated with the electromagnetic field and it is the light that promotes the proliferation of un-stimulated osteoblasts.

  16. Spatially selective photoconductive stimulation of live neurons

    OpenAIRE

    Campbell, Jacob; Singh, Dipika; Hollett, Geoffrey; Dravid, Shashank M; Sailor, Michael J.; Arikkath, Jyothi

    2014-01-01

    Synaptic activity is intimately linked to neuronal structure and function. Stimulation of live cultured primary neurons, coupled with fluorescent indicator imaging, is a powerful technique to assess the impact of synaptic activity on neuronal protein trafficking and function. Current technology for neuronal stimulation in culture include chemical techniques or microelectrode or optogenetic based techniques. While technically powerful, chemical stimulation has limited spatial resolution and mi...

  17. NONINVASIVE BRAIN STIMULATION IN TRAUMATIC BRAIN INJURY

    OpenAIRE

    Demirtas-Tatlidede, Asli; Vahabzadeh-Hagh, Andrew M.; Bernabeu, Montserrat; Tormos, Jose M.; Pascual-Leone, Alvaro

    2012-01-01

    Brain stimulation techniques have evolved in the last few decades with more novel methods capable of painless, noninvasive brain stimulation. While the number of clinical trials employing noninvasive brain stimulation continues to increase in a variety of medication-resistant neurological and psychiatric diseases, studies evaluating their diagnostic and therapeutic potential in traumatic brain injury (TBI) are largely lacking. This review introduces different techniques of noninvasive brain s...

  18. Stimulation of motor tracts in multiple sclerosis.

    OpenAIRE

    Berardelli, A; Inghilleri, M; Cruccu, G.; Fornarelli, M; Accornero, N; Manfredi, M.

    1988-01-01

    Percutaneous electrical stimulation of the motor cortex was used to evaluate corticospinal conduction to upper-limb motoneurons in 29 patients with multiple sclerosis. Central motor conduction abnormalities were correlated with clinical signs and somatosensory evoked potentials. Muscle responses to cortical stimulation were altered in 20 patients. The most common abnormality was increased central motor conduction time; in two cases the responses to cortical stimulation were absent. Abnormalit...

  19. Auditory stimulation and cardiac autonomic regulation

    OpenAIRE

    Vitor E Valenti; Guida, Heraldo L.; Frizzo, Ana C F; Cardoso, Ana C. V.; Vanderlei, Luiz Carlos M; Luiz Carlos de Abreu

    2012-01-01

    Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation bet...

  20. Conception of Electro-Stimulation System

    OpenAIRE

    Adil Salbi; Seddik Bri

    2014-01-01

    The aim of this work is to suggest a reliable solution of electro-stimulation making it possible to restore defective functions of the nervous systems among certain patients. This solution consists in creating a signal similar to that arriving of the central nervous system. Thus, work presented aims to design an electronic circuit of stimulation allowing the contraction of the muscle to restore its function by a biphasic train of electric impulse. This stimulator system is composed of a clock...

  1. Motivation and Stimulation in the Company

    OpenAIRE

    Stehnova, Barbora

    2013-01-01

    This bachelor thesis deals with employees´ stimulation in a company. The theoretic part explains basic concepts of motivation and stimulation and defines the differences between them. It formulates the sources of motivation, defines material and immaterial factors of stimulation and characterizes important theories of motivation. The practical part of the thesis is focused on a research of employees´ motivation in a company Iveco Czech Republic Inc. This is a company which produces buses in V...

  2. ``Bloch wave'' modification of stimulated Raman by stimulated Brillouin scattering

    Science.gov (United States)

    Dodd, E. S.; Vu, H. X.; DuBois, D. F.; Bezzerides, B.

    2013-03-01

    Using the reduced-description particle-in-cell (RPIC) method, we study the coupling of backward stimulated Raman scattering (BSRS) and backward stimulated Brillouin scattering (BSBS) in regimes where the reflectivity involves the nonlinear behavior of particles trapped in the daughter plasma waves. The temporal envelope of a Langmuir wave (LW) obeys a Schrödinger equation where the potential is the periodic electron density fluctuation resulting from an ion-acoustic wave (IAW). The BSRS-driven LWs in this case have a Bloch wave structure and a modified dispersion due to the BSBS-driven spatially periodic IAW, which includes frequency band gaps at kLW˜kIAW/2˜k0 (kLW, kIAW, and k0 are the wave number of the LW, IAW, and incident pump electromagnetic wave, respectively). This band structure and the associated Bloch wave harmonic components are distinctly observed in RPIC calculations of the electron density fluctuation spectra and this structure may be observable in Thomson scatter. Bloch wave components grow up in the LW spectrum, and are not the result of isolated BSRS. Self-Thomson scattered light from these Bloch wave components can have forward scattering components. The distortion of the LW dispersion curve implies that the usual relationship connecting the frequency shift of the BSRS-scattered light and the density of origin of this light may become inaccurate. The modified LW frequency results in a time-dependent frequency shift that increases as the IAW grows, detunes the BSRS frequency matching condition, and reduces BSRS growth. A dependence of the BSRS reflectivity on the IAW Landau damping results because this damping determines the levels of IAWs. The time-dependent reflectivity in our simulations is characterized by bursts of sub-picosecond pulses of BSRS alternating with multi-ps pulses of BSBS, and BSRS is observed to decline precipitously as soon as SBS begins to grow from low levels. In strong BSBS regimes, the Bloch wave effects in BSRS are

  3. Tc-99m imaging agents

    International Nuclear Information System (INIS)

    A wide range of pharmaceuticals for labeling with Tc-99m, developed by the Soreq Radiopharmaceuticals Department, is described. Details of the production and quality control of 13 kits are given, as well as the range of results required for consistently high quality imaging agents

  4. Antibacterial activities of antineoplastic agents.

    OpenAIRE

    Bodet, C A; Jorgensen, J H; Drutz, D J

    1985-01-01

    Fourteen antineoplastic agents were examined for in vitro antibacterial activity against 101 aerobic and anaerobic bacterial isolates representing indigenous human microflora and selected opportunistic pathogens. Only 5-fluorouracil, mitomycin, and etoposide demonstrated inhibitory effects at achievable plasma concentrations, while the remaining drugs lacked appreciable antibacterial activities.

  5. Raspberry Pi for secret agents

    CERN Document Server

    Sjogelid, Stefan

    2015-01-01

    This book is an easy-to-follow guide with practical examples in each chapter. Suitable for the novice and expert alike, each topic provides a fast and easy way to get started with exciting applications and also guides you through setting up the Raspberry Pi as a secret agent toolbox.

  6. Identity Management in Agent Systems

    NARCIS (Netherlands)

    Brazier, F.M.T.; Groot, de D.R.A.

    2006-01-01

    If agent-based applications are to be used in large scale, open environments, security is a main issue; digital identity management (DIDM) an essential element. DIDM is needed to be able to determine the rights and obligations of the four main

  7. Kriitikute lemmikfilm on "Agent Sinikael"

    Index Scriptorium Estoniae

    2003-01-01

    Eesti Filmiajakirjanike Ühing andis kümnendat korda välja auhinda Aasta film 2002. Parimaks filmiks tunnistati mängufilm "Agent Sinikael" : režissöör Marko Raat. Viimane sai preemiaks Neitsi Maali kuju ja 12 000 krooni

  8. Improving agents using reliable communication

    Science.gov (United States)

    Zheng, Jinbin

    2013-10-01

    Recent advances in introspective modalities and linear time symmetries do not necessarily obviate the need for web browsers [1]. In our research, we disprove the exploration of agents, which embodies the appropriate principles of electrical engineering. Here we demonstrate that even though semaphores and XML [1] are mostly incompatible, randomized algorithms and write-back caches are mostly incompatible.

  9. Foodborne illness and microbial agents

    Science.gov (United States)

    Foodborne illnesses result from the consumption of food containing microbial agents such as bacteria, viruses, parasites or food contaminated by poisonous chemicals or bio-toxins. Pathogen proliferation is due to nutrient composition of foods, which are capable of supporting the growth of microorgan...

  10. Bridging humans via agent networks

    International Nuclear Information System (INIS)

    Recent drastic advance in telecommunication networks enabled the human organization of new class, teleorganization, which differ from any existing organization in that the organization which is easy to create by using telecommunication networks is virtual and remote, that people can join multiple organizations simultaneously, and that the organization can involve people who may not know each other. In order to enjoy the recent advance in telecommunication, the agent networks to help people organize themselves are needed. In this paper, an architecture of agent networks, in which each agent learns the preference or the utility functioin of the owner, and acts on behalf of the owner in maintaining the organization, is proposed. When an agent networks supports a human organization, the conventional human interface is divided into personal and social interfaces. The functionalities of the social interface in teleconferencing and telelearning were investigated. In both cases, the existence of B-ISDN is assumed, and the extension to the business meeting scheduling using personal handy phone (PHS) networks with personal digital assistant (PDA) terminals is expected. These circumstances are described. Mutual selection protocols (MSP) and their dynamic properties are explained. (K.I.)

  11. Securiosides A and B, novel acylated triterpene bisdesmosides with selective cytotoxic activity against M-CSF-stimulated macrophages.

    Science.gov (United States)

    Kuroda, M; Mimaki, Y; Sashida, Y; Kitahara, M; Yamazaki, M; Yui, S

    2001-02-12

    We report the discovery of securiosides A (1) and B (2), novel acylated triterpene bisdesmosides, isolated from the roots of Securidaca inappendiculata. Securiosides A and B showed potent selective cytotoxic activity against M-CSF-stimulated macrophages and were suggested to have potential as new agents for the treatment of inflammatory diseases such as RA and atherosclerosis. PMID:11212113

  12. Optical stimulation of peripheral nerves in vivo

    Science.gov (United States)

    Wells, Jonathon D.

    This dissertation documents the emergence and validation of a new clinical tool that bridges the fields of biomedical optics and neuroscience. The research herein describes an innovative method for direct neurostimulation with pulsed infrared laser light. Safety and effectiveness of this technique are first demonstrated through functional stimulation of the rat sciatic nerve in vivo. The Holmium:YAG laser (lambda = 2.12 mum) is shown to operate at an optimal wavelength for peripheral nerve stimulation with advantages over standard electrical neural stimulation; including contact-free stimulation, high spatial selectivity, and lack of a stimulation artifact. The underlying biophysical mechanism responsible for transient optical nerve stimulation appears to be a small, absorption driven thermal gradient sustained at the axonal layer of nerve. Results explicitly prove that low frequency optical stimulation can reliably stimulate without resulting in tissue thermal damage. Based on the positive results from animal studies, these optimal laser parameters were utilized to move this research into the clinic with a combined safety and efficacy study in human subjects undergoing selective dorsal rhizotomy. The clinical Holmium:YAG laser was used to effectively stimulate human dorsal spinal roots and elicit functional muscle responses recorded during surgery without evidence of nerve damage. Overall these results predict that this technology can be a valuable clinical tool in various neurosurgical applications.

  13. Screening of carbonaceous nanoporous materials for capture of nerve agents.

    Science.gov (United States)

    Kowalczyk, Piotr; Gauden, Piotr A; Terzyk, Artur P; Neimark, Alexander V

    2013-01-01

    A strategy for combined experimental and computational screening of candidate carbonaceous materials for capturing highly volatile nerve agents at ambient temperature using physisorption. Based on theoretical calculations of Henry constants and zero-coverage adsorption enthalpies for sarin and DMMP (its common stimulant) adsorbed in model slit-shaped carbon pores at 298 K, we found the following. Slit-shaped carbon pores with pore width ~0.5 nm are optimal for agent adsorption due to strong confinement of adsorbed molecules. Agent adsorption enthalpy at zero coverage computed for optimal pore width is very high and reaches ~83 kJ mol(-1). Widening of pore width above ~1 nm results in a significant decrease of the Henry constant and zero-coverage adsorption enthalpy (~44 kJ mol(-1)). Polydispersity of studied candidate carbonaceous materials strongly affects adsorption capacity for DMMP under the operating conditions. The optimal carbonaceous adsorbent, pitch-based P7 activated carbon fiber, adsorbed ~100 μg g(-1) DMMP at 0.03 μg m(-3). Commercial Norit activated carbon adsorbed only ~20 μg g(-1) DMMP at 0.03 μg m(-3). Surprisingly, a small shift of the pore size distribution towards wider micropores has a great impact on agent adsorption. Because the adsorption enthalpies computed at zero coverage weakly dependent on pore size, the heat released during agent adsorption is similar for all studied candidate adsorbents (i.e.~55-60 kJ mol(-1)). PMID:23165364

  14. Anchor Toolkit - a secure mobile agent system

    OpenAIRE

    Mudumbai, Srilekha S.; Johnston, William; Essiari, Abdelilah

    2008-01-01

    Mobile agent technology facilitates intelligent operation in software systems with less human interaction. Major challenge to deployment of mobile agents include secure transmission of agents and preventing unauthorized access to resources between interacting systems, as either hosts, or agents, or both can act maliciously. The Anchor toolkit, designed by LBNL, handles the transmission and secure management of mobile agents in a heterogeneous distributed computing environment. It provide...

  15. Providing Reliable Agents for Electronic Commerce

    OpenAIRE

    Straßer, Markus; Rothermel, Kurt; Maihöfer, Christian

    1998-01-01

    It is widely agreed that mobile agents in conjunction with WWW technology will provide the technical foundation for future electronic commerce. A prerequisite for the use of mobile agents in a commercial environment is, that agents have to be executed reliable, independent of communication and node failure. In this paper, we first present a recently proposed fault-tolerant protocol to ensure the exactly-once execution of an agent by monitoring the agents execut...

  16. Halide test agent replacement study

    Energy Technology Data Exchange (ETDEWEB)

    Banks, E.M.; Freeman, W.P.; Kovach, B.J. [and others

    1995-02-01

    The intended phaseout of the chlorofluorocarbons (CFCs) from commercial use required the evaluation of substitute materials for the testing for leak paths through both individual adsorbers and installed adsorbent banks. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) is in charge of maintaining the standards and codes specifying adsorbent leak test methods for the nuclear safety related air cleaning systems. The currently published standards and codes cite the use of R-11, R-12 and R-112 for leak path test agents. All of these compounds are CFCs. There are other agencies and organizations (USDOE, USDOD and USNRC) also specifying testing for leak paths or in some cases for special life tests using the above compounds. The CONAGT has recently developed criteria for the suitability evaluation of substitute test agents. On the basis of these criteria, several compounds were evaluated for their acceptability as adsorbent bed leak and life test agents. The ASME CONAGT Test Agent Qualification Criteria. The test agent qualification is based on the following parameters: (1) Similar retention times on activated carbons at the same concentration levels as one of the following: R-11, R-12, R-112 or R-112a. (2) Similar lower detection limit sensitivity and precision in the concentration range of use as R-11, R-12, R-112 and R-112a. (3) Gives the same in-place leak test results as R-11, R-12, R-112, or R-112a. (4) Chemical and radiological stability under the use conditions. (5) Causes no degradation of the carbon and its impregnant or of the other NATS components under the use conditions. (6) Is listed in the USEPA Toxic Substances Control Act (TSCA) inventory for commercial use.

  17. Biologic agents in juvenile spondyloarthropathies.

    Science.gov (United States)

    Katsicas, María Martha; Russo, Ricardo

    2016-01-01

    The juvenile spondyloarthropathies (JSpA) are a group of related rheumatic diseases characterized by involvement of peripheral large joints, axial joints, and entheses (enthesitis) that begin in the early years of life (prior to 16(th) birthday).The nomenclature and concept of spondyloarthropathies has changed during the last few decades. Although there is not any specific classification of JSpA, diseases under the spondyloarthropathy nomenclature umbrella in the younger patients include: the seronegative enthesitis and arthropathy (SEA) syndrome, juvenile ankylosing spondylitis, reactive arthritis, and inflammatory bowel disease-associated arthritis. Moreover, the ILAR criteria for Juvenile Idiopathic Arthritis includes two categories closely related to spondyloarthritis: Enthesitis-related arthritis and psoriatic arthritis.We review the pathophysiology and the use of biological agents in JSpA. JSpA are idiopathic inflammatory diseases driven by an altered balance in the proinflammatory cytokines. There is ample evidence on the role of tumor necrosis factor (TNF) and interleukin-17 in the physiopathology of these entities. Several non-biologic and biologic agents have been used with conflicting results in the treatment of these complex diseases. The efficacy and safety of anti-TNF agents, such as etanercept, infliximab and adalimumab, have been analysed in controlled and uncontrolled trials, usually showing satisfactory outcomes. Other biologic agents, such as abatacept, tocilizumab and rituximab, have been insufficiently studied and their role in the therapy of SpA is uncertain. Interleukin-17-blocking agents are promising alternatives for the treatment of JSpA patients in the near future. Recommendations for the treatment of patients with JSpA have recently been proposed and are discussed in the present review. PMID:26968522

  18. Fibroblast Response to Lanthanoid Metal Ion Stimulation: Potential Contribution to Fibrotic Tissue Injury

    OpenAIRE

    Jenkins, William,; Perone, Patricia; Walker, Kyle; Bhagavathula, Narasimharao; Aslam, Muhammad Nadeem; DaSilva, Marissa; Dame, Michael K.; Varani, James

    2011-01-01

    The purpose of this study was to compare each of the 14 naturally occurring lanthanoid metal ions for ability to stimulate pro-fibrotic responses in human dermal fibroblasts. When fibroblasts were exposed to individual lanthanoids over the concentration range of 1–100 μM, increased proliferation was observed with each of the agents as compared with control cells that were already proliferating rapidly in a growth factor-enriched culture medium. Dose-response differences were observed among th...

  19. The role of pre-operative androgen stimulation in hypospadias surgery

    OpenAIRE

    Kaya, Cevdet; Radmayr, Christian

    2014-01-01

    The hormonal stimulation for the purpose of penile enlargement before the hypospadias repair has been commonly used, but rarely reported. In addition to functional outcome, dihydrotestosterone (DHT) pretreatment has been suggested to improve cosmetic outcome in a preliminary randomized study. Since the randomized and controlled clinical trials on this topic are insufficient, the hormonal agent, the route of administration, dosing schedule, and the timing of treatment has been remained controv...

  20. Migration Dynamics in Artificial Agent Societies

    Directory of Open Access Journals (Sweden)

    Harjot Kaur

    2014-02-01

    Full Text Available An Artificial Agent Society can be defined as a collection of agents interacting with each other for some purpose and/or inhabiting a specific locality, possibly in accordance to some common norms/rules. These societies are analogous to human and ecological societies, and are an expanding and emerging field in research about social systems. Social networks, electronic markets and disaster management organizations can be viewed as such artificial (open agent societies and can be best understood as computational societies. Members of such artificial agent societies are heterogeneous intelligent software agents which are operating locally and cooperating and coordinating with each other in order to achieve goals of an agent society. These artificial agent societies have some kind of dynamics existing in them in terms of dynamics of Agent Migration, Role-Assignment, Norm- Emergence, Security and Agent-Interaction. In this paper, we have described the dynamics of agent migration process, starting from the various types of agent migration, causes or reasons for agent migration, consequences of agent migration, and an agent migration framework to model the its behavior for migration of agents between societies.

  1. Laser interrogation of surface agents (LISA) for chemical agent reconnaissance

    Science.gov (United States)

    Higdon, N. S.; Chyba, Thomas H.; Richter, Dale A.; Ponsardin, Patrick L.; Armstrong, Wayne T.; Lobb, C. T.; Kelly, Brian T.; Babnick, Robert D.; Sedlacek, Arthur J., III

    2002-06-01

    Laser Interrogation of Surface Agents (LISA) is a new technique which exploits Raman scattering to provide standoff detection and identification of surface-deposited chemical agents. ITT Industries, Advanced Engineering and Sciences Division is developing the LISA technology under a cost-sharing arrangement with the US Army Soldier and Biological Chemical Command for incorporation on the Army's future reconnaissance vehicles. A field-engineered prototype LISA-Recon system is being designed to demonstrate on-the- move measurements of chemical contaminants. In this article, we will describe the LISA technique, data form proof-of- concept measurements, the LISA-Recon design, and some of the future realizations envisioned for military sensing applications.

  2. Modulation of the arsenite-induced expression of stress proteins by reducing agents

    OpenAIRE

    Kato, Kanefusa; Ito, Hidenori; Okamoto, Keiko

    1997-01-01

    We examined the effects of reducing agents on the expression of heat shock protein 27 (hsp27), αB crystallin, and hsp70 in C6 rat glioma cells in response to stress. Cells were exposed to arsenite (100 µM for 1 h) in the presence of dithiothreitol at various concentrations (0.03–2 mM), and the accumulation of all three proteins was markedly stimulated in cells that had been exposed to arsenite in the presence of a low concentration (0.03–0.1 mM) of dithiothreitol. Stimulation of these arsenit...

  3. Thermally stimulated discharge conductivity study of zinc oxide thermoelectrets

    Indian Academy of Sciences (India)

    Vijaya S Sangawar; Manisha C Golchha

    2014-10-01

    The present work deals with transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermally stimulated discharge current (TSDC) study of inorganic metal oxide (ZnO) nanoparticles and its thermoelectrets. The thermoelectrets were prepared by applying different electric polarizing field (P) at constant polarizing temperature (P), for constant polarization time (P). The TSDC study was carried out in the temperature region of 313–473 K. It was observed that the conductivity of ZnO samples increases with the increase in temperature and polarizing field. The dependence of TSDC data on polarizing agents, i.e. field and temperature shows Arrhenius type of behviour and is explained on the basis of variable range hopping mechanism.

  4. Gastric electrical stimulation: a report of two cases.

    LENUS (Irish Health Repository)

    Sibartie, V

    2012-02-03

    Gastroparesis refractory to prokinetic agents poses a major challenge to the physician and patient, alike. In the past 5 years, electrical methods to treat gastroparesis have emerged from animal and human experiments to a potentially valuable tool in clinical gastroenterology. One of these methods, known as gastric electrical stimulation (GES), is being increasingly used in specialized centres worldwide, but had never been tried in Ireland. We describe here our experience with the first two implantations of gastric neurostimulators performed in Ireland and the outcome with these 2 patients. Our results at 6 months show reduction in symptoms and improvement in quality of life, which is encouraging and should prompt further evaluation of GES for patients with gastroparesis refractory to medical therapy.

  5. Role of 5α-reductase inhibitors in androgen-stimulated skin disorders.

    Science.gov (United States)

    Azzouni, Faris; Zeitouni, Nathalie; Mohler, James

    2013-02-01

    5α-reductase (5α-R) isozymes are ubiquitously expressed in human tissues. This enzyme family is composed of 3 members that perform several important biologic functions. 5α-R isozymes play an important role in benign prostate hyperplasia, prostate cancer, and androgen-stimulated skin disorders, which include androgenic alopecia, acne, and hirsutism. Discovery of 5α-R type 2 deficiency in 1974 sparked interest in development of pharmaceutical agents to inhibit 5α-R isozymes, and 2 such inhibitors are currently available for clinical use: finasteride and dutasteride. 5α-R inhibitors are US Food and Drug Administration (FDA)-approved for the treatment of benign prostate hyperplasia. Only finasteride is FDA-approved for treatment of male androgenic alopecia. This article reviews the pathophysiology of androgen-stimulated skin disorders and the key clinical trials using 5α-R inhibitors in the treatment of androgen-stimulated skin disorders. PMID:23377402

  6. The New Agent: A Qualitative Study to Strategically Adapt New Agent Professional Development

    Science.gov (United States)

    Baker, Lauri M.; Hadley, Gregg

    2014-01-01

    The qualitative study reported here assessed the needs of agents related to new agent professional development to improve the current model. Agents who participated in new agent professional development within the last 5 years were selected to participate in focus groups to determine concerns and continued needs. Agents enjoyed networking and…

  7. Biological agents in management of osteoporosis.

    Science.gov (United States)

    Tella, Sri Harsha; Gallagher, J Christopher

    2014-11-01

    Osteoporosis is a skeletal disease associated with an imbalance between formation and resorption, leading to net loss of bone mass, loss of bone microarchitecture, and development of fractures. Bone resorption is primarily due to an activation of osteoclastogenesis and an increase in receptor activator of nuclear factor kappa-B ligand (RANKL) expression, a cytokine involved in the final pathway of the osteoclast cycle.Recent studies of genetic diseases led to the discovery of the wingless-type (Wnt) signaling pathway that plays a major role in bone formation. Further work showed that sclerostin produced by osteocytes and the Dickkopf (DKK1) protein secreted in bone were negative regulators of the Wnt signaling bone formation pathway that act directly by binding to the co-receptors LRP5 and LRP6 of WnT and thereby inhibiting the anabolic Wnt pathway. This understanding of the bone remodeling led to the discovery of new biological drugs that target these pathways and have been evaluated in clinical trials.The current article discusses the role of these newer "biological" agents in management of osteoporosis. Denosumab, a human monoclonal antibody that specifically binds RANKL, blocks the binding of RANK to its ligand markedly reducing bone resorption, increases bone density, and reduces fractures and is approved for osteoporosis. Parathyroid hormone PTH 1-34 (teriparatide) stimulates bone formation through inhibition of sclerostin, DKK1, and frizzled protein; increases BMD; improves microarchitecture; and decreases fractures and is approved for osteoporosis. The anti-sclerostin antibodies (romosozumab, blosozumab) increase bone mass by neutralizing the negative effects of sclerostin on the Wnt signaling pathway. These biologics are being evaluated now in a clinical trial and early data looks promising. Cathepsin K is a proteolytic enzyme that degrades bone matrix and inhibitors such as odanacatib show increasing bone density and perhaps decreased fractures. The

  8. On the possible role of stimulation duration for after-effects of transcranial alternating current stimulation

    OpenAIRE

    Stefan Rach; Toralf Neuling; Herrmann, Christoph S.

    2015-01-01

    Transcranial alternating current stimulation is a novel method that allows application of sinusoidal currents to modulate brain oscillations and cognitive processes. Studies in humans have demonstrated tACS after-effects following stimulation durations in the range of minutes. However, such after-effects are absent in animal studies using much shorter stimulation protocols in the range of seconds. Thus, stimulation duration might be a critical parameter for after-effects to occur. To test thi...

  9. CATS-based Agents That Err

    Science.gov (United States)

    Callantine, Todd J.

    2002-01-01

    This report describes preliminary research on intelligent agents that make errors. Such agents are crucial to the development of novel agent-based techniques for assessing system safety. The agents extend an agent architecture derived from the Crew Activity Tracking System that has been used as the basis for air traffic controller agents. The report first reviews several error taxonomies. Next, it presents an overview of the air traffic controller agents, then details several mechanisms for causing the agents to err in realistic ways. The report presents a performance assessment of the error-generating agents, and identifies directions for further research. The research was supported by the System-Wide Accident Prevention element of the FAA/NASA Aviation Safety Program.

  10. Radioprotection: mechanism and radioprotective agents including honeybee venom

    International Nuclear Information System (INIS)

    Since 1949, a great deal of research has been carried on the radioprotective action of chemical substances. These substances have shown to reduce mortality when administered to animals prior to exposure to a lethal dose of radiation. This fact is of considerable importance since it permits reduction of radiation-induced damage and provides prophylactic treatment for the damaging effects produced by radiotherapy. The following radioprotection mechanisms were proposed: free radical scavenger, repair by hydrogen donation to target molecules formation of mixed disulfides, delay of cellular division and induction of hypoxia in the tissues. Radioprotective agents have been divided into four major groups: the thiol compounds, other sulfur compounds, pharmacological agents (anesthetic drugs, analgesics, tranquilizers, etc.) and other radioprotective agents (WR-1065, WR-2721, vitamins C and E, glutathione, etc.). Several studies revealed the radioprotective action of Apis mellifera honeybee venom as well as that of its components mellitin and histamine. Radioprotective activity of bee venom involves mainly the stimulation of the hematopoietic system. In addition, release of histamine and reduction in oxygen tension also contribute to the radioprotective action of bee venom. (author)

  11. Radioprotection: mechanism and radioprotective agents including honeybee venom

    Energy Technology Data Exchange (ETDEWEB)

    Varanda, E.A.; Tavares, D.C. [UNESP, Araraquara, SP (Brazil). Escola de Ciencias Farmaceuticas. Dept. de Ciencias Biologicas

    1998-07-01

    Since 1949, a great deal of research has been carried on the radioprotective action of chemical substances. These substances have shown to reduce mortality when administered to animals prior to exposure to a lethal dose of radiation. This fact is of considerable importance since it permits reduction of radiation-induced damage and provides prophylactic treatment for the damaging effects produced by radiotherapy. The following radioprotection mechanisms were proposed: free radical scavenger, repair by hydrogen donation to target molecules formation of mixed disulfides, delay of cellular division and induction of hypoxia in the tissues. Radioprotective agents have been divided into four major groups: the thiol compounds, other sulfur compounds, pharmacological agents (anesthetic drugs, analgesics, tranquilizers, etc.) and other radioprotective agents (WR-1065, WR-2721, vitamins C and E, glutathione, etc.). Several studies revealed the radioprotective action of Apis mellifera honeybee venom as well as that of its components mellitin and histamine. Radioprotective activity of bee venom involves mainly the stimulation of the hematopoietic system. In addition, release of histamine and reduction in oxygen tension also contribute to the radioprotective action of bee venom. (author)

  12. Digital electronic bone growth stimulator

    Energy Technology Data Exchange (ETDEWEB)

    Kronberg, J.W.

    1993-01-01

    The present invention relates to the electrical treatment of biological tissue. In particular, the present invention discloses a device that produces discrete electrical pulse trains for treating osteoporosis and accelerating bone growth. According to its major aspects and broadly stated, the present invention consists of an electrical circuit configuration capable of generating Bassett-type waveforms shown with alternative signals provide for the treatment of either fractured bones or osteoporosis. The signal generator comprises a quartz clock, an oscillator circuit, a binary divider chain, and a plurality of simple, digital logic gates. Signals are delivered efficiently, with little or no distortion, and uniformly distributed throughout the area of injury. Perferably, power is furnished by widely available and inexpensive radio batteries, needing replacement only once in several days. The present invention can be affixed to a medical cast without a great increase in either weight or bulk. Also, the disclosed stimulator can be used to treat osteoporosis or to strengthen a healing bone after the cast has been removed by attaching the device to the patient`s skin or clothing.

  13. Evolution of a predictive internal model in an embodied and situated agent.

    Science.gov (United States)

    Gigliotta, Onofrio; Pezzulo, Giovanni; Nolfi, Stefano; Nolfi, Sefano

    2011-12-01

    We show how simulated robots evolved for the ability to display a context-dependent periodic behavior can spontaneously develop an internal model and rely on it to fulfill their task when sensory stimulation is temporarily unavailable. The analysis of some of the best evolved agents indicates that their internal model operates by anticipating sensory stimuli. More precisely, it anticipates functional properties of the next sensory state rather than the exact state that sensors will assume. The characteristics of the states that are anticipated and of the sensorimotor rules that determine how the agents react to the experienced states, however, ensure that they produce very similar behaviour during normal and blind phases in which sensory stimulation is available or is self-generated by the agent, respectively. Agents' internal models also ensure an effective transition during the phases in which agents' internal dynamics is decoupled and re-coupled with the sensorimotor flow. Our results suggest that internal models might have arisen for behavioral reasons and successively exapted for other cognitive functions. Moreover, the obtained results suggest that self-generated internal states should not necessarily match in detail the corresponding sensory states and might rather encode more abstract and motor-oriented information. PMID:21604186

  14. Violet stimulated luminescence: geo- or thermochronometer?

    DEFF Research Database (Denmark)

    Ankjærgaard, Christina; Guralnik, Benny; Porat, N.;

    2015-01-01

    The method of quartz optically stimulated luminescence (OSL) dating is widely used, but generally limited to the past ~0.1 million years (Ma) due to early saturation of the desired signal. Violet stimulated luminescence (VSL) of quartz has previously been shown as a promising alternative, with a...

  15. Deep Stimulation at Newberry Volcano EGS Demonstration

    Science.gov (United States)

    Grasso, K.; Cladouhos, T. T.; Petty, S.; Garrison, G. H.; Nordin, Y.; Uddenberg, M.; Swyer, M.

    2014-12-01

    The Newberry Volcano EGS Demonstration is a 5 year field project designed to demonstrate recent technological advances for engineered geothermal systems (EGS) development. Advances in reservoir stimulation, diverter, and monitoring are being tested in a hot (>300 C), dry well (NWG 55-29) drilled in 2008. These technologies could reduce the cost of electrical power generation. The project began in 2010 with two years of permitting, technical planning, and development of a project-specific Induced Seismicity Mitigation Plan (ISMP), and is funded in part by the Department of Energy. In 2012, the well was hydraulically stimulated with water at pressures below the principle stress for 7 weeks, resulting in hydroshearing. The depth of stimulation was successfully shifted by injection of two pills of Thermally-degradable Zonal Isolation Materials (TZIMs). Injectivity changes, thermal profiles and seismicity indicate that fracture permeability in well NWG 55-29 was enhanced during stimulation. This work successfully demonstrated the viability of large-volume (40,000 m3), low-pressure stimulation coupled with non-mechanical diverter technology, and microseismic monitoring for reservoir mapping. Further analysis and field testing in 2013 indicates further stimulation will be required in order to develop an economically viable reservoir, and is scheduled in 2014. The 2014 stimulation will use improved stimulation and monitoring equipment, better knowledge based on 2012 outcomes, and create a deep EGS reservoir in the hottest part of the wellbore.

  16. Brain Stimulation May Help People with Anorexia

    Science.gov (United States)

    ... 2016 (HealthDay News) -- Brain stimulation may ease major symptoms of the eating disorder anorexia nervosa, a typically hard-to-treat condition, ... these findings suggest that brain stimulation may reduce symptoms of anorexia by ... PLoS One . "Anorexia nervosa is thought to affect up to 4 percent ...

  17. Pseudomonas putida Stimulates Primordia on Agaricus bitorquis.

    Science.gov (United States)

    Colauto, Nelson B; Fermor, Terry R; Eira, Augusto F; Linde, Giani A

    2016-04-01

    Casing layer is one step of Agaricus bisporus cultivation where there is a competitive environment with a high number of microorganisms and diversity interacting with mycelia. It is suggested that a minimal community of these microorganisms would be necessary to stimulate fructification. However, A. bisporus is not able to produce primordia in sterile casing layers or Petri dishes. Thus, the objective of this study was to characterize bacterial microbiota of casing layers from A. bisporus cultivation, isolate, identify and characterize the bacteria responsible for the stimulation of primordium and their action mechanism using Agaricus bitorquis as a primordium stimulation model. Bacterial and Pseudomonas spp. communities of different casing layers of A. bisporus cultivation were collected and quantified. It was concluded that Pseudomonas spp. corresponds to 75-85% of bacterial population of the casing layers in A. bisporus cultivation and among those 12% are Pseudomonas putida. Four biochemical assays were used to identify P. putida. In vitro primordium stimulation of living P. putida and non-living bacterial suspensions, after chemical or physical treatments, was tested using A. bitorquis as a primordium stimulation model. Primordium stimulation assay was registered by photographs, and micrographs of vertical cut of primordium were registered by scanning electron microscope. Interaction of living P. putida with A. bitorquis mycelia is capable of stimulating primordial instead of non-living bacterial suspensions. Stimulation of A. bitorquis primordia does not imply or is related to mycelial growth inhibition, but a hierarchical relation of primordium succession and development is suggested. PMID:26742772

  18. Consensus paper: combining transcranial stimulation with neuroimaging

    DEFF Research Database (Denmark)

    Siebner, Hartwig R; Bergmann, Til O; Bestmann, Sven;

    2009-01-01

    In the last decade, combined transcranial magnetic stimulation (TMS)-neuroimaging studies have greatly stimulated research in the field of TMS and neuroimaging. Here, we review how TMS can be combined with various neuroimaging techniques to investigate human brain function. When applied during ne...

  19. Ovarian stimulation and granulosa-cell tumour.

    Science.gov (United States)

    Willemsen, W; Kruitwagen, R; Bastiaans, B; Hanselaar, T; Rolland, R

    1993-04-17

    Ovarian stimulation in the treatment of infertility is far from physiological because patients and their ovaries are exposed to high concentrations of gonadotropins. Many studies have focused on the two most common side-effects of ovarian stimulation--ie, hyperstimulation and multiple pregnancy. We describe 12 patients in whom granulosa-cell tumour was discovered after ovarian stimulation treatment with clomiphene citrate and/or gonadotropins. Although we cannot prove a causal link between the tumour and the medication, investigations in animals have shown a relation between gonadotropin exposition and the development of granulosa-cell tumours. The possible relation of ovarian stimulation and granulosa-cell tumours in human beings has not been published before. We postulate three explanations for this finding; first, the granulosa-cell tumour is present in the ovary, waiting for a hormonal trigger; second, increased follicle stimulating hormone concentrations are oncogenic to granulosa cell; and third, the onset of the granulosa-cell tumour during ovarian stimulation is coincidental. We recommend that ovarian stimulation is done only if there is a valid indication after proper assessment of the ovaries, and that women who have had ovarian stimulation are followed for longer than at present. PMID:8096944

  20. Stimulation of seeds by low dose irradiation

    International Nuclear Information System (INIS)

    The first section of the bibliography lists materials on the stimulation of seeds by low dose irradiation, with particular reference to stimulation of germination and yield. The second section contains a small number of selected references on seed irradiation facilities. (author)

  1. Biological effects of mutagenic agents

    International Nuclear Information System (INIS)

    There is an increasing body of evidence that mutagenic agents (biological, chemical and physical) play an important role in the etiology of human diseases. Mutations may occur in the germinal as well as in the somatic cells. Mutations of the germ cells may result on infertility or fertilization of damaged cells, the later leading to abortion or birth of a malformed fetus. Somatic-cells mutations may have various biological effects, depending on the period of the human life at which the mutation occurs. If it occurs during the prenatal life, a teratogenic or carcinogenic effect will be observed. If the somatic cell is damaged during the postnatal life, this will lead to neoplastic transformation. Therefore it is extremely important to know the mutagenic, teratogenic and carcinogenic effects of various biological, chemical and physical agents in order to eliminate them from our environment. (author). 13 refs, 4 figs, 1 tab

  2. Extension agents and conflict narratives

    DEFF Research Database (Denmark)

    Bond, Jennifer Lauren

    2016-01-01

    Purpose: This work investigated the narratives of development extensionists in relation to natural resource conflict, in order to understand the competing discourses surrounding the wicked problems of natural resource management in Laikipia County, Kenya. Methodology: Q methodology was used to...... professionals from government, non-government, faith-based and private organizations. Findings: Four factors were elicited from the data, labelled—A: ‘Improved Leadership’; B: ‘Resource-centred conflict’; C: ‘Improved Governance’; and D: ‘Improved Management’. Practical Implications: Narratives of neo...... resource conflict. Originality: This work contributes to a growing body of literature interested in the role of extension agents in conflict management. By applying Q methodology, this work has shown that while extension agents are involved in conflict management, their perceptions of these conflicts are...

  3. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    This thesis investigates the possibilities in applying Operations Research (OR) to autonomous vehicular traffic. The explicit difference to most other research today is that we presume that an agent is present in every vehicle - hence Agent Based Individual Traffic guidance (ABIT). The next...... that the system can be divided into two separate constituents. The immediate dispersion, which is used for small areas and quick response, and the individual alleviation, which considers the longer distance decision support. Both of these require intrinsicate models and cost functions which at the...... beginning of the project were not previously considered. We define a special inseparable cost function and develop a solution complex capable of using this cost function. In relation to calibration and estimation of statistical models used for dynamic route guidance we worked with generating random number...

  4. [Infectious agents and autoimmune diseases].

    Science.gov (United States)

    Riebeling-Navarro, C; Madrid-Marina, V; Camarena-Medellín, B E; Peralta-Zaragoza, O; Barrera, R

    1992-01-01

    In this paper the molecular aspects of the relationships between infectious agents and autoimmune diseases, the mechanisms of immune response to infectious agents, and the more recent hypotheses regarding the cause of autoimmune diseases are discussed. The antigens are processed and selected by their immunogenicity, and presented by HLA molecules to the T cell receptor. These events initiate the immune response with the activation and proliferation of T-lymphocytes. Although there are several hypotheses regarding the cause of autoimmune diseases and too many findings against and in favor of them, there is still no conclusive data. All these hypothesis and findings are discussed in the context of the more recent advances. PMID:1615352

  5. Oral agents in multiple sclerosis.

    Science.gov (United States)

    Lorefice, L; Fenu, G; Frau, J; Coghe, G C; Marrosu, M G; Cocco, E

    2015-01-01

    Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system. Disease-modifying drugs licensed for MS treatment have been developed to reduce relapse rates and halt disease progression. The majority of current MS drugs involve regular, parenteral administration, affecting long-term adherence and thus reducing treatment efficacy. Over the last two decades great progress has been made towards developing new MS therapies with different modes of action and biologic effects. In particular, oral drugs have generated much interest because of their convenience and positive impact on medication adherence. Fingolimod was the first launched oral treatment for relapsing-remitting MS; recently, Teriflunomide and Dimethyl fumarate have also been approved as oral disease-modifying agents. In this review, we summarize and discuss the history, pharmacodynamics, efficacy, and safety of oral agents that have been approved or are under development for the selective treatment of MS. PMID:25924620

  6. Logical Theories for Agent Introspection

    DEFF Research Database (Denmark)

    Bolander, Thomas

    2004-01-01

    Artificial intelligence systems (agents) generally have models of the environments they inhabit which they use for representing facts, for reasoning about these facts and for planning actions. Much intelligent behaviour seems to involve an ability to model not only one's external environment but...... self-reference. In the standard approach taken in artificial intelligence, the model that an agent has of its environment is represented as a set of beliefs. These beliefs are expressed as logical formulas within a formal, logical theory. When the logical theory is expressive enough to allow...... introspective reasoning, the presence of self-reference causes the theory to be prone to inconsistency. The challenge therefore becomes to construct logical theories supporting introspective reasoning while at the same time ensuring that consistency is retained. In the thesis, we meet this challenge by devising...

  7. Mechanistic aspects of radioprotection by todralazine hydrochloride, a hematopoietic stem cell expanding agent

    International Nuclear Information System (INIS)

    Previously, we have reported todralazine hydrochloride, an antihypertensive drug, as a radioprotector and hematopoietic stem cell (HSC) expanding agent. The present study aims at unraveling mechanistic aspects of its radioprotective and HSC expanding potential. Zebrafish Tg (cmyb:GFP) embryos treated with 5 μM todralazine from 24-36 hours post fertilization (hpf), increased the number of HSCs (∼ 2 folds) at aorta gonad mesonephros (AGM) region. Similarly, the expression of HSC marker genes, runx1 (3.3 folds) and cMyb (1.4 folds) were also found to be increased. Further, todralazine also accelerated hematopoietic lineage production, erythropoiesis, as evaluated in chemical induced anemic model in zebrafish. Genome wide expression changes in todralazine treated embryos (from 24-36 hpf) using microarray, revealed up and down regulation of 645 and 429 genes respectively. Pathway analysis using DAVID database strongly suggested up regulation of wnt pathway (p<0.019253), which is known to involve in HSC expansion, in todralazine pre-treated embryos. NOS1, known to have its role in HSC expansion through wnt pathway, has been significantly upregulated (1.54 folds; q PCR) by todralazine treatment (from 24-36 hpf). Todralazine treatment (∼30 minutes; 20 Gy) led to a significant upregulation of antioxidant genes (SOD, catalase), DNA damage response genes (p53, p21, GADD45) and nucleotide excision repair genes (XPC, XPA, XPF, XPD) when compared to irradiated control. Immunohistochemical analysis of DNA damage marker (γH2AX) (30 minutes post irradiation), further supported radiation induced DNA damage and protection by todralazine pre-treatment. Corroborating these results, pre-irradiation treatment of todralazine reduced radiation induced apoptosis (caspase 3 assay). Overall, the results suggest that, todralazine protects zebrafish from radiation induced damages by upregulating antioxidant defense system, DNA damage recognition, DNA repair machinery and by reducing cell

  8. The Development of Educational Games Supported by a Pedagogical Tutor Agent

    Science.gov (United States)

    da Silva Lewandowski, Franciele; Pereira, Adriana Soares

    New technologies of information provide facilities for the didactic means of education. This article presents the development of two educational games supported by agents that help students during their interaction with the games. The proposed agent is based on a pedagogical concept that seeks to respect students’ individual development and learning. The educational games are: “Password Game”, which stimulates logic reasoning; and “Math Space”, which helps the basic learning of mathematics. They were developed in Flash programming, and were aimed at children from the first to the third years of Elementary School.

  9. Topical agents in burn care

    OpenAIRE

    Momčilović Dragan

    2002-01-01

    Introduction Understanding of fluid shifts and recognition of the importance of early and appropriate fluid replacement therapy have significantly reduced mortality in the early post burn period. After the bum patient successfully passes the resuscitation period, the burn wound represents the greatest threat to survival. History Since the dawn of civilization, man has been trying to find an agent which would help burn wounds heal, and at the same time, not harm general condition of the injure...

  10. Building Hybrid Soft Computing Agents

    Czech Academy of Sciences Publication Activity Database

    Neruda, Roman

    Anheim : ACTA Press, 2003 - (Castillo, O.), s. 7-11 ISBN 0-88986-347-4. [IASTED International Conference on Neural Networks and Computational Intelligence. Cancun (MX), 19.05.2003-21.05.2003] R&D Projects: GA ČR(CZ) GP201/03/P163 Institutional research plan: CEZ:AV0Z1030915 Keywords : evolutionary algorithms * multi - agent system s * hybrid methods Subject RIV: BA - General Mathematics

  11. MSA AGENT FOR MULTIMEDIA APPLICATIONS

    OpenAIRE

    Aruna Rani; A. K. Gautam

    2011-01-01

    The MSA Agent is the software developed to design rectangular and U slotted micro strip antenna.It is applied for the various applications such as satellite communications, UHF applications. Within the multimedia frequency range the developed software is tested and analyzed for various results. The software is developed using genetic algorithm. This provides extra flexibility and new capability to design rectangular and U slotted micro strip antenna for multimedia application also. The result...

  12. Provably Bounded-Optimal Agents

    OpenAIRE

    Russell, S J; Subramanian, D.

    1995-01-01

    Since its inception, artificial intelligence has relied upon a theoretical foundation centered around perfect rationality as the desired property of intelligent systems. We argue, as others have done, that this foundation is inadequate because it imposes fundamentally unsatisfiable requirements. As a result, there has arisen a wide gap between theory and practice in AI, hindering progress in the field. We propose instead a property called bounded optimality. Roughly speaking, an agent is boun...

  13. Autonomous Behavior of Computational Agents

    Czech Academy of Sciences Publication Activity Database

    Vaculín, Roman; Neruda, Roman

    Wien : Springer-Verlag, 2005 - (Ribiero, B.; Albrecht, R.; Dobnikar, A.; Pearson, D.; Steele, N.), s. 514-517 ISBN 3-211-24934-6. [ICANNGA'2005 /7./. Coimbra (PT), 21.03.2005-23.03.2005] R&D Projects: GA AV ČR 1ET100300419 Institutional research plan: CEZ:AV0Z10300504 Keywords : computational agents * autonomous behavior * reasoning Subject RIV: BA - General Mathematics

  14. Agent Simulation of Chain Bankruptcy

    OpenAIRE

    Yuichi Ikeda; Yoshi Fujiwara; Wataru Souma; Hideaki Aoyama; Hiroshi Iyetomi

    2007-01-01

    We have conducted an agent-based simulation of chain bankruptcy. The propagation of credit risk on a network, i.e., chain bankruptcy, is the key to nderstanding largesized bankruptcies. In our model, decrease of revenue by the loss of accounts payable is modeled by an interaction term, and bankruptcy is defined as a capital deficit. Model parameters were estimated using financial data for 1,077 listed Japanese firms. Simulations of chain bankruptcy on the real transaction network consisting o...

  15. Crimen organizado y agente encubierto

    OpenAIRE

    Herrero Reus, Ignacio

    2014-01-01

    Uno de los objetivos de la justicia penal actual es la lucha contra la criminalidad organizada, bien por su propia naturaleza de “crimen organizado”, bien porque presenta elementos trasnacionales que impiden su investigación a fondo. Todo ello exige la creación de recursos que permitan la investigación de dichos delitos, recursos como el de infiltración de los agentes policiales, objeto del trabajo.

  16. Optical nerve stimulation for a vestibular prosthesis

    Science.gov (United States)

    Harris, David M.; Bierer, Steven M.; Wells, Jonathon D.; Phillips, James O.

    2009-02-01

    Infrared Nerve Stimulation (INS) offers several advantages over electrical stimulation, including more precise spatial selectivity and improved surgical access. In this study, INS and electrical stimulation were compared in their ability to activate the vestibular branch of the VIIIth nerve, as a potential way to treat balance disorders. The superior and lateral canals of the vestibular system of Guinea pigs were identified and approached with the aid of precise 3-D reconstructions. A monopolar platinum stimulating electrode was positioned near the ampullae of the canals, and biphasic current pulses were used to stimulate vestibular evoked potentials and eye movements. Thresholds and input/output functions were measured for various stimulus conditions. A short pulsed diode laser (Capella, Lockheed Martin-Aculight, Inc., Bothell WA) was placed in the same anatomical position and various stimulus conditions were evaluated in their ability to evoke similar potentials and eye movements.

  17. Development of VCSELs for optical nerve stimulation

    Science.gov (United States)

    Dummer, Matthew; Johnson, Klein; Hibbs-Brenner, Mary; Keller, Matthew; Gong, Tim; Wells, Jonathon; Bendett, Mark

    2011-03-01

    Neural stimulation using infrared optical pulses has numerous potential advantages over traditional electrical stimulation, including improved spatial precision and no stimulation artifact. However, realization of optical stimulation in neural prostheses will require a compact and efficient optical source. One attractive candidate is the vertical cavity surface emitting laser. This paper presents the first report of VCSELs developed specifically for neurostimulation applications. The target emission wavelength is 1860 nm, a favorable wavelength for stimulating neural tissues. Continuous wave operation is achieved at room temperature, with maximum output power of 2.9 mW. The maximum lasing temperature observed is 60° C. Further development is underway to achieve power levels necessary to trigger activation thresholds.

  18. Point Electric Stimulation and Children's Amblyopia

    Institute of Scientific and Technical Information of China (English)

    YAN Xing-ke; CHU Hui-ju; WANG Fu-chun; YANG Bo; GAO Yang; HAN Chou-ping

    2007-01-01

    To observe the therapeutic efficacy of electric stimulation on points for children's amblyopia.Method:Ninety children amblyopia cases with ametropia upon correction were randomized into three groups:point electric stimulation,comprehensive conventional therapy and integrative therapy of the above two.And then visual function changes of kids in the three groups were observed.Results:Among the above three therapies,the recovery rates of point electric stimulation,comprehensive conventional therapy and integrative therapy of the two were 83.9%,82.6%and 94.25 respectively,showing no significant difierence(P>0.05) among the three groups.Conclusion:Point electric stimulation has similar action with comprehensive conventional therapy in the treatment of children's amblyopia,and the combination of the two therapies has better effect,indicating point electric stimulation can speed up recovery of visual function of kids with amblyopia.

  19. Regimen of ovarian stimulation affects oocyte and therefore embryo quality.

    Science.gov (United States)

    Bosch, Ernesto; Labarta, Elena; Kolibianakis, Efstratios; Rosen, Mitchell; Meldrum, David

    2016-03-01

    Without any doubt the regimen used to mature multiple capable oocytes for IVF impacts IVF outcomes. Studies have indicated that the inclusion of LH activity, adjuvant agents such as growth hormone (GH), and regimens providing for simultaneous action of both LH and FSH during final oocyte maturation may have beneficial effects on IVF outcomes. Because of the difficulty in improving IVF outcomes in poor responders, the studies on GH are of particular interest. As pointed out in this review, the apparent beneficial effects of GH on oocyte competence may also apply to older women or to normal responders with reduced embryo quality. A much more difficult question is whether and how much ovarian stimulation impacts on oocyte competence. Paradoxically it seems that there are not demonstrated differences between the stimulated and the natural unstimulated cycle, whereas studies in laboratory animals and IVF patients have shown deleterious effects of higher compared with lower doses of gonadotropins. Recent studies suggest that the use of high doses of gonadotropins as an independent factor correlates negatively with the probability of live birth, whereas a high ovarian response per se is associated with better cumulative pregnancy rates, owing to the availability of more euploid and good-quality embryos. Although adjunctive use of androgens has not been discussed here, it is briefly covered in the first review of this series. PMID:26826273

  20. Epidermal growth factor-stimulated protein phosphorylation in rat hepatocytes

    International Nuclear Information System (INIS)

    Epidermal growth factor (EGF) causes a 6-fold increase in the phosphorylation state of a cytosolic protein (pp36, M/sub r/ = 36,000, pI = 5.5) in hepatocytes isolated from fasted, male, Wistar rats. Stimulation of 32P incorporation is observed as early as 1 min following treatment of hepatocytes with EGF and is still present at 30 min after exposure to the growth factor. The phosphate incorporated into pp36 in response to EGF is located predominantly in serine but not tyrosine residues. Phosphorylation of pp36 does not occur in response to insulin or to agents which specifically activate the cAMP-dependent protein kinase (S/sub p/ -cAMPS), protein kinase C (PMA) or Ca2+/calmodulin-dependent protein kinases (A23187) in these cells. Prior treatment of hepatocytes with the cAMP analog, S/sub p/-cAMPS, or ADP-ribosylation of N/sub i/, the inhibitory GTP-binding protein of the adenylate cyclase complex, does not prevent EGF-stimulated phosphorylation of pp36. However, as seen in other cell types, pretreatment of hepatocytes with PMA abolishes all EGF-mediated responses including phosphorylation of pp36. These results suggest that EGP specifically activates an uncharacterized, serine protein kinase in hepatocytes that is distal to the intrinsic EGF receptor tyrosine protein kinase. The rapid activation of this kinase suggests that it may play an important role in the early response of the cell to EGF

  1. Dimensions and Issues of Mobile Agent Technology

    Directory of Open Access Journals (Sweden)

    Yashpal Singh

    2012-09-01

    Full Text Available Mobile Agent is a type of software system which acts “intelligently” on one’s behalf with the feature of autonomy, learning ability and most importantly mobility. Now mobile agents are gaining interest in the research community. In this article mobile agents will be addressed as tools for mobile computing. Mobile agents have been used in applications ranging from network management to information management. We present mobile agent concept, characteristics, classification, need, applications and technical constraints in the mobile technology. We also provide a brief case study about how mobile agent is used for information retrieval.

  2. Antagonistic formation motion of cooperative agents

    Institute of Scientific and Technical Information of China (English)

    卢婉婷; 代明香; 薛方正

    2015-01-01

    This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonis-tic interactions. A distributed formation control algorithm is proposed for each agent to realize the antagonistic formation motion. A sufficient condition is derived to ensure that all agents make an antagonistic formation motion in a distributed manner. It is shown that all agents can be spontaneously divided into several groups, and agents in the same group collab-orate while agents in different groups compete. Finally, a numerical simulation is included to demonstrate our theoretical results.

  3. Agent planning in AgScala

    Science.gov (United States)

    Tošić, Saša; Mitrović, Dejan; Ivanović, Mirjana

    2013-10-01

    Agent-oriented programming languages are designed to simplify the development of software agents, especially those that exhibit complex, intelligent behavior. This paper presents recent improvements of AgScala, an agent-oriented programming language based on Scala. AgScala includes declarative constructs for managing beliefs, actions and goals of intelligent agents. Combined with object-oriented and functional programming paradigms offered by Scala, it aims to be an efficient framework for developing both purely reactive, and more complex, deliberate agents. Instead of the Prolog back-end used initially, the new version of AgScala relies on Agent Planning Package, a more advanced system for automated planning and reasoning.

  4. A++: An Agent Oriented Programming Language

    Directory of Open Access Journals (Sweden)

    Deyi Xue

    2004-08-01

    Full Text Available A new Agent-Oriented Programming (AOP language called A++ is introduced in this research for developing agent-based distributed systems. In this work, agent-oriented programming is defined as a programming method with characteristics of distribution, autonomy, concurrency, and mobility. Both agents and objects can be modeled in A++. In addition to data and methods that can be defined in objects including classes and instances, each agent is also associated with an independent computing process in agent-oriented programming.

  5. Pharmacologic Agents for Chronic Diarrhea.

    Science.gov (United States)

    Lee, Kwang Jae

    2015-10-01

    Chronic diarrhea is usually associated with a number of non-infectious causes. When definitive treatment is unavailable, symptomatic drug therapy is indicated. Pharmacologic agents for chronic diarrhea include loperamide, 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, diosmectite, cholestyramine, probiotics, antispasmodics, rifaximin, and anti-inflammatory agents. Loperamide, a synthetic opiate agonist, decreases peristaltic activity and inhibits secretion, resulting in the reduction of fluid and electrolyte loss and an increase in stool consistency. Cholestyramine is a bile acid sequestrant that is generally considered as the first-line treatment for bile acid diarrhea. 5-HT3 receptor antagonists have significant benefits in patients with irritable bowel syndrome (IBS) with diarrhea. Ramosetron improves stool consistency as well as global IBS symptoms. Probiotics may have a role in the prevention of antibiotic-associated diarrhea. However, data on the role of probiotics in the treatment of chronic diarrhea are lacking. Diosmectite, an absorbent, can be used for the treatment of chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. Antispasmodics including alverine citrate, mebeverine, otilonium bromide, and pinaverium bromide are used for relieving diarrheal symptoms and abdominal pain. Rifaximin can be effective for chronic diarrhea associated with IBS and small intestinal bacterial overgrowth. Budesonide is effective in both lymphocytic colitis and collagenous colitis. The efficacy of mesalazine in microscopic colitis is weak or remains uncertain. Considering their mechanisms of action, these agents should be prescribed properly. PMID:26576135

  6. Multi-agent autonomous system

    Science.gov (United States)

    Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

    2010-01-01

    A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.

  7. An Agent Based Classification Model

    CERN Document Server

    Gu, Feng; Greensmith, Julie

    2009-01-01

    The major function of this model is to access the UCI Wisconsin Breast Can- cer data-set[1] and classify the data items into two categories, which are normal and anomalous. This kind of classifi cation can be referred as anomaly detection, which discriminates anomalous behaviour from normal behaviour in computer systems. One popular solution for anomaly detection is Artifi cial Immune Sys- tems (AIS). AIS are adaptive systems inspired by theoretical immunology and observed immune functions, principles and models which are applied to prob- lem solving. The Dendritic Cell Algorithm (DCA)[2] is an AIS algorithm that is developed specifi cally for anomaly detection. It has been successfully applied to intrusion detection in computer security. It is believed that agent-based mod- elling is an ideal approach for implementing AIS, as intelligent agents could be the perfect representations of immune entities in AIS. This model evaluates the feasibility of re-implementing the DCA in an agent-based simulation environ- ...

  8. 14th International Conference on Practical Applications of Agents and Multi-Agent Systems : Special Sessions

    CERN Document Server

    Escalona, María; Corchuelo, Rafael; Mathieu, Philippe; Vale, Zita; Campbell, Andrew; Rossi, Silvia; Adam, Emmanuel; Jiménez-López, María; Navarro, Elena; Moreno, María

    2016-01-01

    PAAMS, the International Conference on Practical Applications of Agents and Multi-Agent Systems is an evolution of the International Workshop on Practical Applications of Agents and Multi-Agent Systems. PAAMS is an international yearly tribune to present, to discuss, and to disseminate the latest developments and the most important outcomes related to real-world applications. It provides a unique opportunity to bring multi-disciplinary experts, academics and practitioners together to exchange their experience in the development of Agents and Multi-Agent Systems. This volume presents the papers that have been accepted for the 2016 in the special sessions: Agents Behaviours and Artificial Markets (ABAM); Advances on Demand Response and Renewable Energy Sources in Agent Based Smart Grids (ADRESS); Agents and Mobile Devices (AM); Agent Methodologies for Intelligent Robotics Applications (AMIRA); Learning, Agents and Formal Languages (LAFLang); Multi-Agent Systems and Ambient Intelligence (MASMAI); Web Mining and ...

  9. Borrelioses, agentes e vetores Borrelioses, agents and vectors: a review

    Directory of Open Access Journals (Sweden)

    Cleber O. Soares

    2000-03-01

    Full Text Available As borrelioses são enfermidades infecciosas determinadas por espiroquetas do gênero Borrelia, agentes transmissíveis, principalmente, por carrapatos aos animais e/ou ao homem. Nesta revisão são apresentadas e discutidas as enfermidades determinadas por borrélias, bem como as características gerais das espiroquetas, os aspectos relacionados a transmissão por artrópodes, as enfermidades nos animais domésticos e silvestres, quanto aos aspectos biológicos e patológicos, a doença de Lyme como principal zoonose do grupo, a associação de borrélia com outros agentes hematozoários e os métodos diagnósticos e a epidemiologia comparativa entre dados obtidos no Brasil com os de outros países. Estas borrelioses possuem características patológicas, clínicas e epidemiológicas variadas de acordo à região fisiográfica, devido à existência de distintas espécies, genoespécies e cepas; estes aspectos variam ainda em função dos artrópodes vetores, da interação vetor-patógeno e dos ecossistemas distintos.Borrelioses are infectous diseases caused by spirochaetes of the genus Borrelia. They are born mainly through ticks at animals and/or human beings. In this review are shown and discussed five groups of diseases determined by borrelia, general characteristics of the spirochaetes, aspects related to transmission by arthropods, biological and pathological aspects of the diseases in domestic and wild animals, Lyme disease as an important zoonosis, the association of borrelia with other hematozoa agents, the diagnostic methods and the comparative epidemiology with data obtained from Brazil and other countries. The borrelioses have pathological, clinical and epidemiological characteristics which vary according to physiographic regions due to the existence of different species, genospecies and strains of borrelia, of arthropod vectors, vector-agent relationship and of different ecocystems.

  10. Stimulating the Comfort of Textile Electrodes in Wearable Neuromuscular Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Hui Zhou

    2015-07-01

    Full Text Available Textile electrodes are becoming an attractive means in the facilitation of surface electrical stimulation. However, the stimulation comfort of textile electrodes and the mechanism behind stimulation discomfort is still unknown. In this study, a textile stimulation electrode was developed using conductive fabrics and then its impedance spectroscopy, stimulation thresholds, and stimulation comfort were quantitatively assessed and compared with those of a wet textile electrode and a hydrogel electrode on healthy subjects. The equivalent circuit models and the finite element models of different types of electrode were built based on the measured impedance data of the electrodes to reveal the possible mechanism of electrical stimulation pain. Our results showed that the wet textile electrode could achieve similar stimulation performance as the hydrogel electrode in motor threshold and stimulation comfort. However, the dry textile electrode was found to have very low pain threshold and induced obvious cutaneous painful sensations during stimulation, in comparison to the wet and hydrogel electrodes. Indeed, the finite element modeling results showed that the activation function along the z direction at the depth of dermis epidermis junction of the dry textile electrode was significantly larger than that of the wet and hydrogel electrodes, thus resulting in stronger activation of pain sensing fibers. Future work will be done to make textile electrodes have similar stimulation performance and comfort as hydrogel electrodes.

  11. Learning other agents` preferences in multiagent negotiation

    Energy Technology Data Exchange (ETDEWEB)

    Bui, H.H.; Kieronska, D.; Venkatesh, S. [Curtin Univ. of Technology, Perth, WA (Australia)

    1996-12-31

    In multiagent systems, an agent does not usually have complete information about the preferences and decision making processes of other agents. This might prevent the agents from making coordinated choices, purely due to their ignorance of what others want. This paper describes the integration of a learning module into a communication-intensive negotiating agent architecture. The learning module gives the agents the ability to learn about other agents` preferences via past interactions. Over time, the agents can incrementally update their models of other agents` preferences and use them to make better coordinated decisions. Combining both communication and learning, as two complement knowledge acquisition methods, helps to reduce the amount of communication needed on average, and is justified in situations where communication is computationally costly or simply not desirable (e.g. to preserve the individual privacy).

  12. Agent Communication Channel Based on BACnet

    Institute of Scientific and Technical Information of China (English)

    Jiang Wen-bin; Zhou Man-li

    2004-01-01

    We analyze the common shortcoming in the existing agent MTPs (message transport protocols). With employing the File object and related service AtomicWriteFile of BACnet (a data communication protocol building automation and control networks), a new method of agent message transport is proposed and implemented. Every agent platform (AP) has one specified File object and agents in another AP can communicate with agents in the AP by using AtomicWriteFile service. Agent messages can be in a variety of formats. In implementation, BACnet/IP and Ethernet are applied as the BACnet data link layers respectively. The experiment results show that the BACnet can provide perfect support for agent communication like other conventional protocols such as hypertext transfer protocol(HTTP), remote method invocation (RMI) etc. and has broken through the restriction of TCP/IP. By this approach, the agent technology is introduced into the building automation control network system.

  13. Analysis and Optimization for Mobile Agent Communication

    Institute of Scientific and Technical Information of China (English)

    YANGBo; LIUDayou

    2005-01-01

    Communication performance is one of the most important factors affecting the efficiency of mobile agent system. Only traditional optimization techniques for communication performance are not enough, especially in large-scale intelligent mobile agent system, so more intelligent optimization techniques are needed. In the background, the paper studies communication of mobile agent system from the viewpoint of performance. The paper makes qualitative and quantitative analysis of four important factors that will affect the communication performance of mobile agent system and presents the communication performance optimization model. The model hasthree primary functions. First, the model provides a formalism method to describe the communication task and process of mobile agent. Second, the model provides a means to make quantitative analysis of the performance of mobile agent system. Third, the model can plan out an optimal communication scheme for mobile agent to minimize the cost of whole communication. The model could thus be a building block for the optimization of the communication behavior of mobile agent.

  14. Comparison of Communication Models for Mobile Agents

    Directory of Open Access Journals (Sweden)

    Xining Li

    2003-04-01

    Full Text Available An agent is a self-contained process being acting on behalf of a user. A Mobile Agent is an agent roaming the internet to access data and services, and carry out its assigned task remotely. This paper will focus on the communication models for Mobile Agents. Generally speaking, communication models concern with problems of how to name Mobile Agents, how to establish communication relationships, how to trace moving agents, and how to guarantee reliable communication. Some existing MA systems are purely based on RPC-style communication, whereas some adopts asynchronous message passing, or event registration/handling. Different communication concepts suitable for Mobile Agents are well discussed in [1]. However, we will investigate these concepts and existing models from a different point view: how to track down agents and deliver messages in a dynamic, changing world.

  15. A Framework for Multi-Agent Planning

    OpenAIRE

    Bos, A; Tonino, J.F.M.; De Weerdt, M.M.; Witteveen, C.

    2000-01-01

    We introduce a computational framework, consisting of resources, skills, goals and services to represent the plans of individual agents and to develop models and algorithms for cooperation processes between a collection of agents.

  16. Porphyria Cutanea Tarda and Agent Orange

    Science.gov (United States)

    ... ZIP code here Porphyria Cutanea Tarda and Agent Orange VA presumes porphyria cutanea tarda (PCT) is related to Veterans' exposure to Agent Orange or other herbicides during military service when the ...

  17. Soft Tissue Sarcomas and Agent Orange

    Science.gov (United States)

    ... ZIP code here Soft Tissue Sarcomas and Agent Orange VA presumes some soft tissue sarcomas in Veterans are related to their exposure to Agent Orange or other herbicides during military service. The soft ...

  18. Electrical stimulation to accelerate wound healing

    Directory of Open Access Journals (Sweden)

    Gaurav Thakral

    2013-09-01

    Full Text Available Background: There are several applications of electrical stimulation described in medical literature to accelerate wound healing and improve cutaneous perfusion. This is a simple technique that could be incorporated as an adjunctive therapy in plastic surgery. The objective of this review was to evaluate the results of randomized clinical trials that use electrical stimulation for wound healing. Method: We identified 21 randomized clinical trials that used electrical stimulation for wound healing. We did not include five studies with treatment groups with less than eight subjects. Results: Electrical stimulation was associated with faster wound area reduction or a higher proportion of wounds that healed in 14 out of 16 wound randomized clinical trials. The type of electrical stimulation, waveform, and duration of therapy vary in the literature. Conclusion: Electrical stimulation has been shown to accelerate wound healing and increase cutaneous perfusion in human studies. Electrical stimulation is an adjunctive therapy that is underutilized in plastic surgery and could improve flap and graft survival, accelerate postoperative recovery, and decrease necrosis following foot reconstruction.

  19. Computational modeling of epidural cortical stimulation

    Science.gov (United States)

    Wongsarnpigoon, Amorn; Grill, Warren M.

    2008-12-01

    Epidural cortical stimulation (ECS) is a developing therapy to treat neurological disorders. However, it is not clear how the cortical anatomy or the polarity and position of the electrode affects current flow and neural activation in the cortex. We developed a 3D computational model simulating ECS over the precentral gyrus. With the electrode placed directly above the gyrus, about half of the stimulus current flowed through the crown of the gyrus while current density was low along the banks deep in the sulci. Beneath the electrode, neurons oriented perpendicular to the cortical surface were depolarized by anodic stimulation, and neurons oriented parallel to the boundary were depolarized by cathodic stimulation. Activation was localized to the crown of the gyrus, and neurons on the banks deep in the sulci were not polarized. During regulated voltage stimulation, the magnitude of the activating function was inversely proportional to the thickness of the CSF and dura. During regulated current stimulation, the activating function was not sensitive to the thickness of the dura but was slightly more sensitive than during regulated voltage stimulation to the thickness of the CSF. Varying the width of the gyrus and the position of the electrode altered the distribution of the activating function due to changes in the orientation of the neurons beneath the electrode. Bipolar stimulation, although often used in clinical practice, reduced spatial selectivity as well as selectivity for neuron orientation.

  20. Modified pulse shapes for effective neural stimulation

    Directory of Open Access Journals (Sweden)

    Lorenz eHofmann

    2011-09-01

    Full Text Available Electrical stimulation of neuronal structures is used as treatment of many neu- rological disorders, e.g. for the treatment of Parkinsons disease via deep brain stimulation. To reduce side effects, to avoid tissue or electrode damage and to increase battery lifetimes, an effective but gentle electrical stimulation is of prime importance. We study different modified pulse shapes for application in deep brain stimulation with respect to their efficiency to initiate neuronal activity. Numeri- cal simulations of two mathematical neuron models are performed to investigate the effectiveness of different modified pulse shapes. According to our results, the considered pulse shapes show a considerably increased efficiency in terms of both activation and entrainment of neural activity. We find that the introduction of a gap of specific and optimized duration in a biphasic pulse and the reversal of the stan- dard pulse phase order yield stimulation protocols that may increase the efficiency and therefore reduce the energy consumption of stimulation. The improvements are achieved only by simple modifications of existing stimulation techniques. The modification of the pulse shapes results in an improvement of up to 50% for both the activation of resting neurons and the entrainment of bursting neurons.