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Sample records for suboptimal nonradioprotective doses

  1. Bone marrow concentrate promotes bone regeneration with a suboptimal-dose of rhBMP-2.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Egashira

    Full Text Available Bone marrow concentrate (BMC, which is enriched in mononuclear cells (MNCs and platelets, has recently attracted the attention of clinicians as a new optional means for bone engineering. We previously reported that the osteoinductive effect of bone morphogenetic protein-2 (BMP-2 could be enhanced synergistically by co-transplantation of peripheral blood (PB-derived platelet-rich plasma (PRP. This study aims to investigate whether BMC can effectively promote bone formation induced by low-dose BMP-2, thereby reducing the undesirable side-effects of BMP-2, compared to PRP. Human BMC was obtained from bone marrow aspirates using an automated blood separator. The BMC was then seeded onto β-TCP granules pre-adsorbed with a suboptimal-dose (minimum concentration to induce bone formation at 2 weeks in mice of recombinant human (rh BMP-2. These specimens were transplanted subcutaneously to the dorsal skin of immunodeficient-mice and the induction of ectopic bone formation was assessed 2 and 4 weeks post-transplantation. Transplantations of five other groups [PB, PRP, platelet-poor plasma (PPP, bone marrow aspirate (BM, and BM-PPP] were employed as experimental controls. Then, to clarify the effects on vertical bone augmentation, specimens from the six groups were transplanted for on-lay placement on the craniums of mice. The results indicated that BMC, which contained an approximately 2.5-fold increase in the number of MNCs compared to PRP, could accelerate ectopic bone formation until 2 weeks post-transplantation. On the cranium, the BMC group promoted bone augmentation with a suboptimal-dose of rhBMP-2 compared to other groups. Particularly in the BMC specimens harvested at 4 weeks, we observed newly formed bone surrounding the TCP granules at sites far from the calvarial bone. In conclusion, the addition of BMC could reduce the amount of rhBMP-2 by one-half via its synergistic effect on early-phase osteoinduction. We propose here that BMC

  2. Treatment of advanced colorectal cancer in a patient with cardiotoxic reactions to 5-fluorouracil and capecitabine using suboptimal doses.

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    Cioffi, Joseph H; Estes, Derek J; Florou, Vaia; Ardalan, Bach

    2017-11-27

    A 32-year-old female with stage IV colorectal cancer and metastasis to the liver experienced cardiotoxic reactions after treatment with 5-fluorouracil and its oral prodrug capecitabine even at two-thirds the recommended dose. After careful considerations, the decision was made to attempt capecitabine retrial at a further suboptimal dose with combination chemotherapy where she no longer experienced cardiac events. As a result, the liver tumour shrank and rectal mass stabilised, tumour markers dropped and she underwent surgical resection of both masses. Later there was local recurrence of disease near the previous liver tumour, so the suboptimal capecitabine therapy was restarted without complaint. The patient became a candidate for a NanoKnife procedure, offering a potentially curative therapy. This case report summarises a novel treatment strategy for those patients with advanced colorectal cancer who experience cardiotoxic reactions to fluoropyrimidines, the active agent of gold standard treatment. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Optimal medication dosing from suboptimal clinical examples: a deep reinforcement learning approach.

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    Nemati, Shamim; Ghassemi, Mohammad M; Clifford, Gari D

    2016-08-01

    Misdosing medications with sensitive therapeutic windows, such as heparin, can place patients at unnecessary risk, increase length of hospital stay, and lead to wasted hospital resources. In this work, we present a clinician-in-the-loop sequential decision making framework, which provides an individualized dosing policy adapted to each patient's evolving clinical phenotype. We employed retrospective data from the publicly available MIMIC II intensive care unit database, and developed a deep reinforcement learning algorithm that learns an optimal heparin dosing policy from sample dosing trails and their associated outcomes in large electronic medical records. Using separate training and testing datasets, our model was observed to be effective in proposing heparin doses that resulted in better expected outcomes than the clinical guidelines. Our results demonstrate that a sequential modeling approach, learned from retrospective data, could potentially be used at the bedside to derive individualized patient dosing policies.

  4. Semiautomated head-and-neck IMRT planning using dose warping and scaling to robustly adapt plans in a knowledge database containing potentially suboptimal plans

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Matthew, E-mail: matthew.schmidt@varian.com; Grzetic, Shelby [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27708 (United States); Lo, Joseph Y. [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27708 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27708 (United States); Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Lutzky, Carly [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Brizel, David M. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27708 (United States); Das, Shiva K. [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27708 and Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27708 (United States)

    2015-08-15

    Purpose: Prior work by the authors and other groups has studied the creation of automated intensity modulated radiotherapy (IMRT) plans of equivalent quality to those in a patient database of manually created clinical plans; those database plans provided guidance on the achievable sparing to organs-at-risk (OARs). However, in certain sites, such as head-and-neck, the clinical plans may not be sufficiently optimized because of anatomical complexity and clinical time constraints. This could lead to automated plans that suboptimally exploit OAR sparing. This work investigates a novel dose warping and scaling scheme that attempts to reduce effects of suboptimal sparing in clinical database plans, thus improving the quality of semiautomated head-and-neck cancer (HNC) plans. Methods: Knowledge-based radiotherapy (KBRT) plans for each of ten “query” patients were semiautomatically generated by identifying the most similar “match” patient in a database of 103 clinical manually created patient plans. The match patient’s plans were adapted to the query case by: (1) deforming the match beam fluences to suit the query target volume and (2) warping the match primary/boost dose distribution to suit the query geometry and using the warped distribution to generate query primary/boost optimization dose-volume constraints. Item (2) included a distance scaling factor to improve query OAR dose sparing with respect to the possibly suboptimal clinical match plan. To further compensate for a component plan of the match case (primary/boost) not optimally sparing OARs, the query dose volume constraints were reduced using a dose scaling factor to be the minimum from either (a) the warped component plan (primary or boost) dose distribution or (b) the warped total plan dose distribution (primary + boost) scaled in proportion to the ratio of component prescription dose to total prescription dose. The dose-volume constraints were used to plan the query case with no human intervention

  5. High dose adenosine for suboptimal myocardial reperfusion after primary PCI : A randomized placebo-controlled pilot study

    NARCIS (Netherlands)

    Stoel, Martin G.; Marques, Koen M. J.; de Cock, Carel C.; Bronzwaer, Jean G. F.; von Birgelen, Clemens; Zijlstra, Felix

    2008-01-01

    Objectives: This study was designed to investigate the influence of high dose intracoronary adenosine on persistent ST-segment elevation after primary percutaneous coronary intervention (PCI). Background: After successful PCI for acute myocardial infarction 40-50% of patients show persistent

  6. Dose Reduction of Caspofungin in Intensive Care Unit Patients with Child Pugh B Will Result in Suboptimal Exposure

    NARCIS (Netherlands)

    Martial, L.C.; Bruggemann, R.J.M.; Schouten, J.A.; Leeuwen, H.J. van; Zanten, A.R. van; Lange, D.W. de; Muilwijk, E.W.; Verweij, P.E.; Burger, D.M.; Aarnoutse, R.E.; Pickkers, P.; Dorlo, T.P.

    2016-01-01

    BACKGROUND AND OBJECTIVES: Caspofungin is an echinocandin antifungal agent used as first-line therapy for the treatment of invasive candidiasis. The maintenance dose is adapted to body weight (BW) or liver function (Child-Pugh score B or C). We aimed to study the pharmacokinetics of caspofungin and

  7. Dose Reduction of Caspofungin in Intensive Care Unit Patients with Child Pugh B Will Result in Suboptimal Exposure

    NARCIS (Netherlands)

    Martial, Lisa C; Brüggemann, Roger J M; Schouten, Jeroen A; van Leeuwen, Henk J; van Zanten, Arthur R; de Lange, Dylan W; Muilwijk, Eline W; Verweij, Paul E; Burger, David M; Aarnoutse, Rob E; Pickkers, Peter; Dorlo, Thomas P C

    2015-01-01

    BACKGROUND AND OBJECTIVES: Caspofungin is an echinocandin antifungal agent used as first-line therapy for the treatment of invasive candidiasis. The maintenance dose is adapted to body weight (BW) or liver function (Child-Pugh score B or C). We aimed to study the pharmacokinetics of caspofungin and

  8. A shooting approach to suboptimal control

    Science.gov (United States)

    Hull, David G.; Sheen, Jyh-Jong

    1991-01-01

    The shooting method is used to solve the suboptimal control problem where the control history is assumed to be piecewise linear. Suboptimal solutions can be obtained without difficulty and can lead to accurate approximate controls and good starting multipliers for the regular shooting method by increasing the number of nodes. Optimal planar launch trajectories are presented for the advanced launch system.

  9. Suboptimal glycemic control in type 2 diabetes

    DEFF Research Database (Denmark)

    Nefs, Giesje; Pouwer, F; Denollet, J

    2012-01-01

    , clinical, lifestyle and psychological factors between 2005 and 2009. The Edinburgh Depression Scale was used to assess symptoms of depressed mood, anhedonia and anxiety. Suboptimal glycemic control was defined as HbA(1c) values ≥7%, with 29.8% of the sample (n=1718) scoring above this cut......-off. In univariate logistic regression analyses, anhedonia was significantly associated with suboptimal glycemic control (OR 1.29, 95% CI 1.09-1.52), while both depressed mood (OR 1.04, 0.88-1.22) and anxiety (OR 0.99, 0.83-1.19) were not. The association between anhedonia and glycemic control remained after...

  10. On Suboptimal Solution of Antagonistic Matrix Games

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    Goryashko Alexander

    2017-01-01

    Full Text Available The paper examines resource allocation games such as Colonel Blotto and Colonel Lotto games with the goal to develop tractable method for building suboptimal solution in mixed strategies of these games without solving the relevant optimization problem. The foundation of proposed method lies in the specific combinatorial properties of the partition games. It turned out that as far as distribution of resource along battlefield is concerned that pure strategies participating in ε-optimal solution possessed specific structure. Numerical experiments showed that these specific structural peculiarities can be easily reproduced utilizing previously found combinatorial properties of partition. As a result, we get ε-optimal solution of partition games and support set mixed strategies can be computed in polynomial time.

  11. Over-the-counter suboptimal dispensing of antibiotics in Uganda

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    Mukonzo JK

    2013-08-01

    : In Uganda, at least four in every ten individuals that visit a health-care facility are treated with an antibiotic. Antibiotics are largely given as over-the-counter drugs at community pharmacies. The number of antibiotic prescribed daily doses/1,000 antibiotic clients does not significantly differ between categories of health-care facilities except at community pharmacies, where lower doses are dispensed compared to other health-care facilities. Keywords: antibiotic, over-the-counter dispensing, suboptimal dosing, Uganda

  12. Audit-based education to reduce suboptimal management of cholesterol in primary care: a before and after study.

    OpenAIRE

    de Lusignan, S; Belsey, J; Hague, N.; Dhoul, N; van Vlymen, J

    2006-01-01

    Statins are recommended for the secondary prevention of cardiovascular disease, although they are often used in suboptimal doses and some patients may not receive lipid-lowering therapy. The Primary Care Data Quality (PCDQ) programme is an audit-based educational intervention.

  13. Suboptimal light conditions influence source-sink metabolism during flowering

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    Annelies eChristiaens

    2016-03-01

    Full Text Available Reliance on carbohydrates during flower forcing was investigated in one early and one late flowering cultivar of azalea (Rhododendron simsii hybrids. Carbohydrate accumulation, invertase activity, and expression of a purported sucrose synthase gene (RsSUS was monitored during flower forcing under suboptimal (natural and optimal (supplemental light light conditions, after a cold treatment (7°C + dark to break flower bud dormancy. Post-production sucrose metabolism and flowering quality was also assessed. Glucose and fructose concentrations and invertase activity increased in petals during flowering, while sucrose decreased. In suboptimal light conditions RsSUS expression in leaves increased as compared to optimal light conditions, indicating that plants in suboptimal light conditions have a strong demand for carbohydrates. However, carbohydrates in leaves were markedly lower in suboptimal light conditions compared to optimal light conditions. This resulted in poor flowering of plants in suboptimal light conditions. Post-production flowering relied on the stored leaf carbon, which could be accumulated under optimal light conditions in the greenhouse. These results show that flower opening in azalea relies on carbohydrates imported from leaves and is source-limiting under suboptimal light conditions.

  14. Suboptimal palliative sedation in primary care: an exploration.

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    Pype, Peter; Teuwen, Inge; Mertens, Fien; Sercu, Marij; De Sutter, An

    2017-06-05

    Palliative sedation is a therapeutic option to control refractory symptoms in terminal palliative patients. This study aims at describing the occurrence and characteristics of suboptimal palliative sedations in primary care and at exploring the way general practitioners (GPs) experience suboptimal palliative sedation in their practice. We conducted a mixed methods study with a quantitative prospective survey in primary care and qualitative semi-structured interviews with GPs. The research team defined suboptimal palliative sedation as a time interval until deep sleep >1.5 h and/ or >2 awakenings after the start of the unconsciousness. Descriptive statistics were calculated on the quantitative data. Thematic analysis was used to analyse interview transcripts. We registered 63 palliative sedations in 1181 home deaths, 27 forms were completed. Eleven palliative sedations were suboptimal: eight due to the long time span until deep sleep; three due the number of unintended awakenings. GPs' interview analysis revealed two major themes: the shifting perception of failure and the burden of responsibility. Suboptimal palliative sedation occurs frequently in primary palliative care. Efficient communication towards family members is needed to prevent them from having unrealistic expectations and to prevent putting pressure on the GP to hasten the procedure. Sharing the burden of decision-making during the procedure with other health care professionals might diminish the heavy responsibility as perceived by GPs.

  15. Suboptimal Rate Adaptive Resource Allocation for Downlink OFDMA Systems

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    Sanam Sadr

    2009-01-01

    Full Text Available This paper aims to study the performance of low complexity adaptive resource allocation in the downlink of OFDMA systems with fixed or variable rate requirements (with fairness consideration. Two suboptimal resource allocation algorithms are proposed using the simplifying assumption of transmit power over the entire bandwidth. The objective of the first algorithm is to maximize the total throughput while maintaining rate proportionality among the users. The proposed suboptimal algorithm prioritizes the user with the highest sensitivity to the subcarrier allocation, and the variance over the subchannel gains is used to define the sensitivity of each user. The second algorithm concerns rate adaptive resource allocation in multiuser systems with fixed rate constraints. We propose a suboptimal joint subchannel and power allocation algorithm which prioritizes the users with the highest required data rates. The main feature of this algorithm is its low complexity while achieving the rate requirements.

  16. Suboptimal care in stillbirths - a retrospective audit study.

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    Saastad, Eli; Vangen, Siri; Frøen, J Frederik

    2007-01-01

    Stillbirth rates have decreased radically over the last decades. One reason for this is improved perinatal care. The aim of this study was to explore whether sub-optimal factors in stillbirths were more frequent among non-western than western women. Population-based perinatal audit of 356 stillbirths after gestational week 23, in 2 Norwegian counties during 1998-2003 (4.2 per 1,000 deliveries); of these 31% were born to non-western women. By audit, the stillbirths were attributed to optimal or sub-optimal care factors. Multivariate methods were used to analyse the data. Sub-optimal factors were identified in 37% of the deaths. When compared to western women, non-western women had an increased risk of stillbirth (OR: 2.2; 95% CI: 1.3-3.8), and an increased risk of sub-optimal care (OR: 2.4; 95% CI: 1.5-3.9). More often, non-western women received sub-optimal obstetric care (plabour progression. A common failure in antenatal care for both groups was unidentified or inadequate management of intrauterine growth restriction or decreased fetal movements. Non-western women were less prone to attend the program for antenatal care or to take the consequences of recommendations from health professionals. Inadequate communication was documented in 47% of non-western mothers; an interpreter was used in 29% of these cases. Non-western women constituted a risk group for sub-optimal care factors in stillbirths. Possibilities for improvements include a reduction of language barriers, better identification and management of growth restriction for both origin groups, and adequate intervention in complicated vaginal births; with increased vigilance towards non-western women.

  17. Sacral Nerve Stimulation for Constipation: Suboptimal Outcome and Adverse Events

    DEFF Research Database (Denmark)

    Maeda, Yasuko; Lundby, Lilli; Buntzen, Steen

    2010-01-01

    Sacral nerve stimulation is an emerging treatment for patients with severe constipation. There has been no substantial report to date on suboptimal outcomes and complications. We report our experience of more than 6 years by focusing on incidents and the management of reportable events....

  18. Optimal and Suboptimal Noises Enhancing Mutual Information in Threshold System

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    Zhai, Qiqing; Wang, Youguo

    2016-05-01

    In this paper, we investigate the efficacy of noise enhancing information transmission in a threshold system. At first, in the frame of stochastic resonance (SR), optimal noise (Opt N) is derived to maximize mutual information (MI) of this nonlinear system. When input signal is discrete (binary), the optimal SR noise is found to have a finite distribution. In contrast, when input signal is continuous, the optimal SR noise is a constant one. In addition, suboptimal SR noises are explored as well with optimization methods when the types of noise added into the system are predetermined. We find that for small thresholds, suboptimal noises do not exist. Only when thresholds reach some level, do suboptimal noises come into effect. Meanwhile, we have discussed the impact of tails in noise distribution on SR effect. Finally, this paper extends the single-threshold system to an array of multi-threshold devices and presents the corresponding efficacy of information transmission produced by optimal and suboptimal SR noises. These results may be beneficial to quantization and coding.

  19. Suboptimal Utilisation of Resources in Sub-Saharan African Higher ...

    African Journals Online (AJOL)

    Suboptimal Utilisation of Resources in Sub-Saharan African Higher Education Institutions: the Case of Teaching Space at Makerere University. ... This means that the institutions need to evaluate their utilization of these resources—to pinpoint their need for the resources and potential for quality assurance. This paper reports ...

  20. When animals misbehave: analogs of human biases and suboptimal choice.

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    Zentall, Thomas R

    2015-03-01

    Humans tend to value rewards more if they have had to work hard to obtain them (justification of effort). Similarly they tend to persist in a task even when they would be better off beginning a new one (sunk cost). Humans also often give greater value to objects of good quality than the same objects together with objects of lesser quality (the less is more effect). Commercial gambling (lotteries and slot machines) is another example of suboptimal choice by humans because on average the rewards are less than the investment. In another example of a systematic bias, when humans try to estimate the probability of the occurrence of a low probability event, they often give too much weight to the results of a test, in spite of the fact that the known probability of a false alarm reduces the predictive value of the test (base rate neglect). In each of these examples, we have found that pigeons show a similar tendency to choose suboptimally. When one can show comparable findings of suboptimal choice in animals it suggests that whereas culture may reinforce certain suboptimal behavior, the behavior is likely to result from the overgeneralization of basic behavioral processes or predisposed heuristics that may have been appropriate in natural environments. This article is part of a Special Issue entitled: "Tribute to Tom Zentall." Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Prevalence and predictors of sub-optimal medication adherence ...

    African Journals Online (AJOL)

    In this study, the levels of adherence, prevalence and the predictors of suboptimal adherence were assessed in a sub-Saharan African setting. Methods: Three hundred and seventy (370) respondents with diagnoses of schizophrenia, bipolar disorder or severe depression were randomly enrolled and interviewed at the ...

  2. Investigating the prevalence, predictors, and prognosis of suboptimal statin use early after a non-ST elevation acute coronary syndrome.

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    Turner, Richard M; Yin, Peng; Hanson, Anita; FitzGerald, Richard; Morris, Andrew P; Stables, Rod H; Jorgensen, Andrea L; Pirmohamed, Munir

    High-potency statin therapy is recommended in the secondary prevention of cardiovascular disease but discontinuation, dose reduction, statin switching, and/or nonadherence occur in practice. To determine the prevalence and predictors of deviation from high-potency statin use early after a non-ST elevation acute coronary syndrome (NSTE-ACS) and its association with subsequent major adverse cardiovascular events (MACE) and all-cause mortality (ACM). A total of 1005 patients from a UK-based prospective NSTE-ACS cohort study discharged on high-potency statin therapy (atorvastatin 80 mg, rosuvastatin 20 mg, or 40 mg daily) were included. At 1 month, patients were divided into constant high-potency statin users, and suboptimal users incorporating statin discontinuation, dose reduction, switching statin to a lower equivalent potency, and/or statin nonadherence. Follow-up was a median of 16 months. There were 156 suboptimal (∼15.5%) and 849 constant statin users. Factors associated in multivariable analysis with suboptimal statin occurrence included female sex (odds ratio 1.75, 95% confidence interval [CI] 1.14-2.68) and muscular symptoms (odds ratio 4.28, 95% CI 1.30-14.08). Suboptimal statin use was associated with increased adjusted risks of time to MACE (hazard ratio 2.10, 95% CI 1.25-3.53, P = .005) and ACM (hazard ratio 2.46, 95% CI 1.38-4.39, P = .003). Subgroup analysis confirmed that the increased MACE/ACM risks were principally attributable to statin discontinuation or nonadherence. Conversion to suboptimal statin use is common early after NSTE-ACS and is partly related to muscular symptoms. Statin discontinuation or non-adherence carries an adverse prognosis. Interventions that preserve and enhance statin utilization could improve post NSTE-ACS outcomes. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  3. Visually suboptimal bananas: How ripeness affects consumer expectation and perception.

    Science.gov (United States)

    Symmank, Claudia; Zahn, Susann; Rohm, Harald

    2017-10-07

    One reason for the significant amount of food that is wasted in developed countries is that consumers often expect visually suboptimal food as being less palatable. Using bananas as example, the objective of this study was to determine how appearance affects consumer overall liking, the rating of sensory attributes, purchase intention, and the intended use of bananas. The ripeness degree (RD) of the samples was adjusted to RD 5 (control) and RD 7 (more ripened, visually suboptimal). After preliminary experiments, a total of 233 participants were asked to judge their satisfaction with the intensity of sensory attributes that referred to flavor, taste, and texture using just-about-right scales. Subjects who received peeled samples were asked after tasting, whereas subjects who received unpeeled bananas judged expectation and, after peeling and tasting, perception. Expected overall liking and purchase intention were significantly lower for RD 7 bananas. Purchase intention was still significantly different between RD 5 and RD 7 after tasting, whereas no difference in overall liking was observed. Significant differences between RD 5 and RD 7 were observed when asking participants for their intended use of the bananas. Concerning the sensory attributes, penalty analysis revealed that only the firmness of the RD 7 bananas was still not just-about-right after tasting. The importance that consumers attribute to the shelf-life of food had a pronounced impact on purchase intention of bananas with different ripeness degree. In the case of suboptimal bananas, the results demonstrate a positive relationship between the sensory perception and overall liking and purchase intention. Convincing consumers that visually suboptimal food is still tasty is of high relevance for recommending different ways of communication. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Subtypes of type I IFN differentially enhance cytokine expression by suboptimally stimulated CD4(+) T cells.

    Science.gov (United States)

    Hillyer, Philippa; Raviv, Nataly; Gold, Doria M; Dougherty, Danielle; Liu, Jie; Johnson, Teresa R; Graham, Barney S; Rabin, Ronald L

    2013-12-01

    Human type I interferons (IFNs) include IFN-β and 12 subtypes of IFN-α. During viral infection, infiltrating memory CD4(+) T cells are exposed to IFNs, but their impact on memory T-cell function is poorly understood. To address this, we pretreated PBMCs with different IFNs for 16 h before stimulation with Staphylococcus aureus enterotoxin B and measured cytokine expression by flow cytometry. IFN-α8 and -α10 most potently enhanced expression of IFN-γ, IL-2, and IL-4. Potency among the subtypes differed most at doses between 10 and 100 U/mL. While enhancement of IL-2 and IL-4 correlated with the time of preincubation with type I IFN, IFN-γ production was enhanced best when IFN-α was added immediately preceding or simultaneously with T-cell stimulation. Comparison of T-cell responses to multiple doses of Staphylococcus aureus enterotoxin B and to peptide libraries from RSV or CMV demonstrated that IFN-α best enhanced cytokine expression when CD4(+) T cells were suboptimally stimulated. We conclude that type I IFNs enhance Th1 and Th2 function with dose dependency and subtype specificity, and best when T-cell stimulation is suboptimal. While type I IFNs may beneficially enhance CD4(+) T-cell memory responses to vaccines or viral pathogens, they may also enhance the function of resident Th2 cells and exacerbate allergic inflammation. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  5. Suboptimal performance on neuropsychological tests in patients with suspected chronic toxic encephalopathy

    NARCIS (Netherlands)

    van Hout, MSE; Schmand, B; Wekking, EM; Hageman, G; Deelman, BG

    Suboptimal performance during neuropsychological testing can seriously complicate assessment in behavioral neurotoxicology. We present data on the prevalence of suboptimal performance in a group of Dutch patients with suspected chronic toxic encephalopathy (CTE) after long-term occupational exposure

  6. Suboptimal performance on neuropsychological tests in patients with suspected chronic toxic encephalopathy

    NARCIS (Netherlands)

    van Hout, Moniek S. E.; Schmand, Ben; Wekking, Ellie M.; Hageman, Gerard; Deelman, Betto G.

    2003-01-01

    Suboptimal performance during neuropsychological testing can seriously complicate assessment in behavioral neurotoxicology. We present data on the prevalence of suboptimal performance in a group of Dutch patients with suspected chronic toxic encephalopathy (CTE) after long-term occupational exposure

  7. Interventions via Social Influence for Emergent Suboptimal Restraint Use

    Directory of Open Access Journals (Sweden)

    Ziad KOBTI

    2013-08-01

    Full Text Available Although restraint use has increased primarily in developed countries, vehicle accident-related injuries and deaths continue to be a problem. Alongside lack of restraint use, studies involving suboptimal restraint use have gained recent popularity. In this study we investigate the use of social influence forinterventions to counter emerging suboptimal restraint use in groups of agents.A multi-agent simulation model is provided where dominant individuals use randomly assigned influence rates to repeatedly alter the knowledge of lessinfluential group members. Cultural influence is implemented via a cultural algorithm and used to simulate individuals affected by beliefs in the community. Objectives include investigating the emergence of patterns of restraint selection and use as well as interventions targeted at more influential agents. Results demonstrate that prominent patterns of behaviour similar to the influentialmembers of the groups do emerge. Furthermore, interventions targeted at influential group members outperform interventions targeted at a percentage of the population at large. Interventions succeed at some level both in the presence and absence of cultural influence.

  8. Optimal inference with suboptimal models: addiction and active Bayesian inference.

    Science.gov (United States)

    Schwartenbeck, Philipp; FitzGerald, Thomas H B; Mathys, Christoph; Dolan, Ray; Wurst, Friedrich; Kronbichler, Martin; Friston, Karl

    2015-02-01

    When casting behaviour as active (Bayesian) inference, optimal inference is defined with respect to an agent's beliefs - based on its generative model of the world. This contrasts with normative accounts of choice behaviour, in which optimal actions are considered in relation to the true structure of the environment - as opposed to the agent's beliefs about worldly states (or the task). This distinction shifts an understanding of suboptimal or pathological behaviour away from aberrant inference as such, to understanding the prior beliefs of a subject that cause them to behave less 'optimally' than our prior beliefs suggest they should behave. Put simply, suboptimal or pathological behaviour does not speak against understanding behaviour in terms of (Bayes optimal) inference, but rather calls for a more refined understanding of the subject's generative model upon which their (optimal) Bayesian inference is based. Here, we discuss this fundamental distinction and its implications for understanding optimality, bounded rationality and pathological (choice) behaviour. We illustrate our argument using addictive choice behaviour in a recently described 'limited offer' task. Our simulations of pathological choices and addictive behaviour also generate some clear hypotheses, which we hope to pursue in ongoing empirical work. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. China suboptimal health cohort study: rationale, design and baseline characteristics.

    Science.gov (United States)

    Wang, Youxin; Ge, Siqi; Yan, Yuxiang; Wang, Anxin; Zhao, Zhongyao; Yu, Xinwei; Qiu, Jing; Alzain, Mohamed Ali; Wang, Hao; Fang, Honghong; Gao, Qing; Song, Manshu; Zhang, Jie; Zhou, Yong; Wang, Wei

    2016-10-13

    Suboptimal health status (SHS) is a physical state between health and disease, characterized by the perception of health complaints, general weakness, chronic fatigue and low energy levels. SHS is proposed by the ancient concept of traditional Chinese medicine (TCM) from the perspective of preservative, predictive and personalized (precision) medicine. We previously created the suboptimal health status questionnaire 25 (SHSQ-25), a novel instrument to measure SHS, validated in various populations. SHSQ-25 thus affords a window of opportunity for early detection and intervention, contributing to the reduction of chronic disease burdens. To investigate the causative effect of SHS in non-communicable chronic diseases (NCD), we initiated the China suboptimal health cohort study (COACS), a longitudinal study starting from 2013. Phase I of the study involved a cross-sectional survey aimed at identifying the risk/protective factors associated with SHS; and Phase II: a longitudinal yearly follow-up study investigating how SHS contributes to the incidence and pattern of NCD. (1) Cross-sectional survey: in total, 4313 participants (53.8 % women) aged from 18 to 65 years were included in the cohort. The prevalence of SHS was 9.0 % using SHS score of 35 as threshold. Women showed a significantly higher prevalence of SHS (10.6 % in the female vs. 7.2 % in the male, P differed significantly between subjects of SHS (SHS score ≥35) and those of ideal health (SHS score difference in prevalence of SHS might partly explain the gender difference of incidence of certain chronic diseases. The COACS will enable a thorough characterization of SHS and establish a cohort that will be used for longitudinal analyses of the interaction between the genetic, lifestyle and environmental factors that contribute to the onset and etiology of targeted chronic diseases. The study together with the designed prospective cohort provides a chance to characterize and evaluate the effect of SHS

  10. Feature-preserving surface mesh smoothing via suboptimal Delaunay triangulation.

    Science.gov (United States)

    Gao, Zhanheng; Yu, Zeyun; Holst, Michael

    2013-01-01

    A method of triangular surface mesh smoothing is presented to improve angle quality by extending the original optimal Delaunay triangulation (ODT) to surface meshes. The mesh quality is improved by solving a quadratic optimization problem that minimizes the approximated interpolation error between a parabolic function and its piecewise linear interpolation defined on the mesh. A suboptimal problem is derived to guarantee a unique, analytic solution that is significantly faster with little loss in accuracy as compared to the optimal one. In addition to the quality-improving capability, the proposed method has been adapted to remove noise while faithfully preserving sharp features such as edges and corners of a mesh. Numerous experiments are included to demonstrate the performance of the method.

  11. Risk of Suboptimal Iodine Intake in Pregnant Norwegian Women

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    Helle Margrete Meltzer

    2013-02-01

    Full Text Available Pregnant women and infants are exceptionally vulnerable to iodine deficiency. The aims of the present study were to estimate iodine intake, to investigate sources of iodine, to identify predictors of low or suboptimal iodine intake (defined as intakes below 100 μg/day and 150 μg/day in a large population of pregnant Norwegian women and to evaluate iodine status in a sub-population. Iodine intake was calculated based on a validated Food Frequency Questionnaire in the Norwegian Mother and Child Cohort. The median iodine intake was 141 μg/day from food and 166 μg/day from food and supplements. Use of iodine-containing supplements was reported by 31.6%. The main source of iodine from food was dairy products, contributing 67% and 43% in non-supplement and iodine-supplement users, respectively. Of 61,904 women, 16.1% had iodine intake below 100 μg/day, 42.0% had iodine intake below 150 μg/day and only 21.7% reached the WHO/UNICEF/ICCIDD recommendation of 250 μg/day. Dietary behaviors associated with increased risk of low and suboptimal iodine intake were: no use of iodine-containing supplements and low intake of milk/yogurt, seafood and eggs. The median urinary iodine concentration measured in 119 participants (69 μg/L confirmed insufficient iodine intake. Public health strategies are needed to improve and secure the iodine status of pregnant women in Norway.

  12. Suboptimal Criterion Learning in Static and Dynamic Environments.

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    Elyse H Norton

    2017-01-01

    Full Text Available Humans often make decisions based on uncertain sensory information. Signal detection theory (SDT describes detection and discrimination decisions as a comparison of stimulus "strength" to a fixed decision criterion. However, recent research suggests that current responses depend on the recent history of stimuli and previous responses, suggesting that the decision criterion is updated trial-by-trial. The mechanisms underpinning criterion setting remain unknown. Here, we examine how observers learn to set a decision criterion in an orientation-discrimination task under both static and dynamic conditions. To investigate mechanisms underlying trial-by-trial criterion placement, we introduce a novel task in which participants explicitly set the criterion, and compare it to a more traditional discrimination task, allowing us to model this explicit indication of criterion dynamics. In each task, stimuli were ellipses with principal orientations drawn from two categories: Gaussian distributions with different means and equal variance. In the covert-criterion task, observers categorized a displayed ellipse. In the overt-criterion task, observers adjusted the orientation of a line that served as the discrimination criterion for a subsequently presented ellipse. We compared performance to the ideal Bayesian learner and several suboptimal models that varied in both computational and memory demands. Under static and dynamic conditions, we found that, in both tasks, observers used suboptimal learning rules. In most conditions, a model in which the recent history of past samples determines a belief about category means fit the data best for most observers and on average. Our results reveal dynamic adjustment of discrimination criterion, even after prolonged training, and indicate how decision criteria are updated over time.

  13. Suboptimal inhibition of platelet cyclo-oxygenase-1 (COX-1) by aspirin in lupus erythematosus: Association with metabolic syndrome

    Science.gov (United States)

    Kawai, Vivian K.; Avalos, Ingrid; Oeser, Annette; Oates, John A.; Milne, Ginger L.; Solus, Joseph F.; Chung, Cecilia P.; Stein, C. Michael

    2013-01-01

    Objectives Low-dose aspirin prevents platelet aggregation by suppressing thromboxane A2 synthesis. However, in some individuals thromboxane A2 suppression by aspirin is impaired, indicating suboptimal inhibition of platelet COX-1 by aspirin. Because patients with systemic lupus erythematosus (SLE) have increased risk of thrombotic events, many receive aspirin; however, the efficacy of aspirin in SLE has not been determined. We examined the hypothesis that aspirin response is impaired in SLE. Methods We assessed the effect of aspirin by measuring concentrations of the stable metabolite of thromboxane A2 - serum thromboxane B2 (sTxB2), before and after treatment with 81 mg daily aspirin for 7 days in 34 patients with SLE and 36 control subjects. The inability to suppress sTxB2 synthesis to aspirin. Results Aspirin almost completely suppressed sTXB2 in control subjects to 1.5, [0.8–2.7] ng/ml (median and interquartile ranges [IQR]), but had less effect in patients with SLE (3.1, [2.2–5.3] ng/ml) (P=0.002). A suboptimal effect of aspirin was present in 15% (5/34) of the patients with SLE but not in control subjects (0/36) (P=0.023). Incomplete responders were more likely to have metabolic syndrome (P=0.048), obesity (P=0.048) and higher concentrations of CRP (P=0.018). Conclusion The pharmacologic effect of aspirin is suboptimal in 15% of patients with SLE but in none of the control subjects, and the suboptimal response was associated with metabolic syndrome, obesity, and higher CRP concentrations. PMID:24022862

  14. No improvement in suboptimal vitamin A status with a randomized, double-blind, placebo-controlled trial of vitamin A supplementation in children with sickle cell disease.

    Science.gov (United States)

    Dougherty, Kelly A; Schall, Joan I; Kawchak, Deborah A; Green, Michael H; Ohene-Frempong, Kwaku; Zemel, Babette S; Stallings, Virginia A

    2012-10-01

    Suboptimal vitamin A status is prevalent in children with type SS sickle cell disease (SCD-SS) and is associated with hospitalizations and poor growth and hematologic status. The supplemental vitamin A dose that optimizes suboptimal vitamin A status in this population is unknown. The efficacy of Recommended Dietary Allowance (RDA) doses (based on age and sex) of vitamin A (300, 400, or 600 μg retinyl palmitate/d) or vitamin A + zinc (10 or 20 mg zinc sulfate/d) compared with placebo to optimize vitamin A status was assessed in children aged 2.0-12.9 y with SCD-SS and a suboptimal baseline serum retinol concentration (children (based on age and sex) failed to improve serum retinol values in either group (vitamin A: n = 23; vitamin A + zinc: n = 18) compared with placebo (n = 21). By 12 mo, the increase (±SD) in serum retinol (3.6 ± 2.8 μg/dL) in those taking 600 μg vitamin A/d was significantly different from the decrease (±SD; -2.8 ± 2.4 μg/dL) in those taking 300 μg/d, which possibly suggests a dose-response relation (P children did not improve serum retinol values in children with SCD-SS, which possibly suggests that higher doses are needed. However, the existence of alternative conclusions emphasizes the need for future research.

  15. Energy expenditures & physical activity in rats with chronic suboptimal nutrition

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    Lifshitz Fima

    2006-01-01

    Full Text Available Abstract Background Sub-optimally nourished rats show reduced growth, biochemical and physiological changes. However, no one has assessed metabolic rate adaptations in rats subjected to chronic suboptimal nutrition (CSN. In this study energy expenditure (EE; kcal/100 g body weight and physical activity (PA; oscillations in weight/min/kg body weight were assessed in rats subjected to three levels of CSN. Results Body weight gain was diminished (76.7 ± 12.0 and 61.6 ± 11.0 g in rats fed 70 and 60% of the ad-libitum fed controls which gained more weight (148.5 ± 32.3 g. The rats fed 80% gained weight similarly to controls (136.3 ± 10.5 g. Percent Fat-free body mass was reduced (143.8 ± 8.7 and 142.0 ± 7.6 g in rats fed 70 and 60% of ad-libitum, but not in those fed 80% (200.8 ± 17.5 g as compared with controls (201.6 ± 33.4 g. Body fat (g decreased in rats fed 80% (19.7 ± 5.3, 70% (15.3 ± 3.5 and 60% (9.6 ± 2.7 of ad-libitum in comparison to controls (26.0 ± 6.7. EE and PA were also altered by CSN. The control rats increased their EE and PA during the dark periods by 1.4 ± 0.8 and 1.7 ± 1.1 respectively, as compared with light the period; whereas CSN rats fed 80 and 70% of ad-libitum energy intake had reduced EE and PA during the dark periods as compared with the light period EE(7.5 ± 1.4 and 7.8 ± 0.6 vs. 9.0 ± 1.2 and 9.7 ± 0.8; p Conclusion CSN rats adapt to mild energy restriction by reducing body fat, EE and PA mainly during the dark period while growth proceeds and lean body mass is preserved. At higher levels of energy restrictions there is decreased growth, body fat and lean mass. Moreover EE and PA are also reduced during both light and dark periods.

  16. Treatment of KPC-producing Enterobacteriaceae: suboptimal efficacy of polymyxins.

    Science.gov (United States)

    de Oliveira, M S; de Assis, D B; Freire, M P; Boas do Prado, G V; Machado, A S; Abdala, E; Pierrotti, L C; Mangini, C; Campos, L; Caiaffa Filho, H H; Levin, A S

    2015-02-01

    Treatment of Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae infections (KPC-EI) remains a challenge. Combined therapy has been proposed as the best choice, but there are no clear data showing which combination therapy is superior. Our aim was to evaluate the effectiveness of antimicrobial regimens for treating KPC-EI. This was a retrospective cohort study of KPC-EI nosocomial infections (based on CDC criteria) between October 2009 and June 2013 at three tertiary Brazilian hospitals. The primary outcomes were the 30-day mortality for all infections and the 30-day mortality for patients with bacteraemia. Risk factors for mortality were evaluated by comparing clinical variables of survivors and nonsurvivors. In this study, 118 patients were included, of whom 78 had bacteraemia. Catheter-related bloodstream infections were the most frequent (43%), followed by urinary tract infections (n = 27, 23%). Monotherapy was used in 57 patients and combined treatment in 61 patients. The most common therapeutic combination was polymyxin plus carbapenem 20 (33%). Multivariate analysis for all infections (n = 118) and for bacteremic infections (n = 78) revealed that renal failure at the end of treatment, use of polymyxin and older age were prognostic factors for mortality. In conclusion, polymyxins showed suboptimal efficacy and combination therapy was not superior to monotherapy. Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  17. Robust Adaptive LCMV Beamformer Based On An Iterative Suboptimal Solution

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    Xiansheng Guo

    2015-06-01

    Full Text Available The main drawback of closed-form solution of linearly constrained minimum variance (CF-LCMV beamformer is the dilemma of acquiring long observation time for stable covariance matrix estimates and short observation time to track dynamic behavior of targets, leading to poor performance including low signal-noise-ratio (SNR, low jammer-to-noise ratios (JNRs and small number of snapshots. Additionally, CF-LCMV suffers from heavy computational burden which mainly comes from two matrix inverse operations for computing the optimal weight vector. In this paper, we derive a low-complexity Robust Adaptive LCMV beamformer based on an Iterative Suboptimal solution (RAIS-LCMV using conjugate gradient (CG optimization method. The merit of our proposed method is threefold. Firstly, RAIS-LCMV beamformer can reduce the complexity of CF-LCMV remarkably. Secondly, RAIS-LCMV beamformer can adjust output adaptively based on measurement and its convergence speed is comparable. Finally, RAIS-LCMV algorithm has robust performance against low SNR, JNRs, and small number of snapshots. Simulation results demonstrate the superiority of our proposed algorithms.

  18. Predictors of Suboptimal Follow-up in Pediatric Cancer Survivors.

    Science.gov (United States)

    May, Leana; Schwartz, David D; Frugé, Ernest; Laufman, Larry; Holm, Suzanne; Kamdar, Kala; Harris, Lynnette; Brackett, Julienne; Unal, Sule; Tanyildiz, Gulsah; Bryant, Rosalind; Suzawa, Hilary; Dreyer, Zoann; Okcu, M Fatih

    2017-04-01

    Attendance to follow-up care after completion of cancer treatment is an understudied area. We examined demographic, clinical, and socioeconomic predictors of follow-up by pediatric cancer patients at a large center in 442 newly diagnosed patients using multivariable logistic regression analyses. Patients who did not return to clinic for at least 1000 days were considered lost to follow-up. Two hundred forty-two (54.8%) patients were lost. In multivariable analyses, the following variables were independent predictors of being lost to follow-up: treatment with surgery alone (odds ratio [OR]=6.7; 95% confidence interval [CI], 3.1-14.9), older age at diagnosis (reference, 0 to 4; ages, 5 to 9: OR=1.8, 95% CI, 1.1-3; ages, 10 to 14: OR=3.3; CI, 1.8-6.1; and ages, 15 and above: OR=4.8; CI, 2.1-11.7), lack of history of stem cell transplantation (OR=2, 95% CI, 1.04-3.7) and lack of insurance (OR=3.4; CI, 1.2-9.2). Hispanic patients had the best follow-up rates (53.7%) compared to whites and blacks (P=0.03). Attendance to long-term follow-up care is suboptimal in childhood cancer survivors. Predictors that were associated with nonattendance can be used to design targeted interventions to improve follow-up care for survivors of pediatric cancer.

  19. Adaptive suboptimal second-order sliding mode control for microgrids

    Science.gov (United States)

    Incremona, Gian Paolo; Cucuzzella, Michele; Ferrara, Antonella

    2016-09-01

    This paper deals with the design of adaptive suboptimal second-order sliding mode (ASSOSM) control laws for grid-connected microgrids. Due to the presence of the inverter, of unpredicted load changes, of switching among different renewable energy sources, and of electrical parameters variations, the microgrid model is usually affected by uncertain terms which are bounded, but with unknown upper bounds. To theoretically frame the control problem, the class of second-order systems in Brunovsky canonical form, characterised by the presence of matched uncertain terms with unknown bounds, is first considered. Four adaptive strategies are designed, analysed and compared to select the most effective ones to be applied to the microgrid case study. In the first two strategies, the control amplitude is continuously adjusted, so as to arrive at dominating the effect of the uncertainty on the controlled system. When a suitable control amplitude is attained, the origin of the state space of the auxiliary system becomes attractive. In the other two strategies, a suitable blend between two components, one mainly working during the reaching phase, the other being the predominant one in a vicinity of the sliding manifold, is generated, so as to reduce the control amplitude in steady state. The microgrid system in a grid-connected operation mode, controlled via the selected ASSOSM control strategies, exhibits appreciable stability properties, as proved theoretically and shown in simulation.

  20. Suboptimal vitamin K status despite supplementation in children and young adults with cystic fibrosis.

    Science.gov (United States)

    Dougherty, Kelly A; Schall, Joan I; Stallings, Virginia A

    2010-09-01

    For children and adolescents with cystic fibrosis (CF) and pancreatic insufficiency, the efficacy of routine vitamin K supplementation to normalize vitamin K status remains unclear. This study examined and determined predictors of vitamin K status in subjects aged 8-25 y with CF and pancreatic insufficiency taking various vitamin K supplements. In 97 subjects, serum 25-hydroxyvitamin D [25(OH)D], dietary intake, vitamin K supplement intake, and vitamin K statusmdashdetermined on the basis of the percentage of serum undercarboxylated osteocalcin (%ucOC; sufficient: lt 20%) and plasma proteins induced by vitamin K absence-factor II (PIVKA-II; n = 60; sufficient: le 2 microg/L)mdashwere assessed. The vitamin K supplementation groups were as follows: lt 150 microg/d (low; multivitamins or no supplement), 150-999 microg/d (middle; CF-specific vitamins), and ge 1000 microg/d (high; mephyton). %ucOC values were compared with 140 healthy subjects aged 6-21 y. In subjects with CF, the median (range) %ucOC was 35% (3%, 76%) and the median (range) for PIVKA-II was 2 (0, 42) micro g/L. Subjects with CF had a higher %ucOC with low [45% (10%, 76%)] and medium [41% (3%, 66%)] supplement intakes but not with a high supplement intake [16% (4%, 72%)] compared with healthy subjects [23% (0%, 43%); both P lt 0.05]. Supplementation group for males and females and 25(OH)D and age for males were significant predictors of vitamin K status. Vitamin K status was often suboptimal despite routine supplementation. Only subjects taking high-dose vitamin K achieved a status similar to healthy subjects, and only the vitamin K supplementation dose predicted vitamin K status for males and females. These data suggest that higher doses of vitamin K are required.

  1. Adjustment of Eculizumab Dosage Pattern in Patients with Atypical Hemolytic Uremic Syndrome with Suboptimal Response to Standard Treatment Pattern

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    Camino García Monteavaro

    2016-01-01

    Full Text Available In patients with atypical hemolytic uremic syndrome (aHUS, complement blocking by eculizumab rapidly halts the process of thrombotic microangiopathy and it is associated with clear long-term hematologic and renal improvements. Eculizumab treatment consists of a 4-week initial phase with weekly IV administration of 900 mg doses, followed by a maintenance phase with a 1,200 mg dose in the fifth week and every 14±2 days thereafter. We present three patients with aHUS and suboptimal response to eculizumab treatment at the usual administration dosage who showed hematologic and renal improvements after an adjustment in the eculizumab treatment protocol.

  2. Determinants of suboptimal breast-feeding practices in Pakistan.

    Science.gov (United States)

    Hazir, Tabish; Akram, Dure-Samin; Nisar, Yasir Bin; Kazmi, Narjis; Agho, Kingsley E; Abbasi, Saleem; Khan, Amira M; Dibley, Michael J

    2013-04-01

    Exclusive breast-feeding is estimated to reduce infant mortality in low-income countries by up to 13 %. The aim of the present study was to determine the risk factors associated with suboptimal breast-feeding practices in Pakistan. A cross-sectional study using data extracted from the multistage cluster sample survey of the Pakistan Demographic and Health Survey 2006-2007. A nationally representative sample of households. Last-born alive children aged 0-23 months (total weighted sample size 3103). The prevalences of timely initiation of breast-feeding, bottle-feeding in children aged 0-23 months, exclusive breast-feeding and predominant breast-feeding in infants aged 0-5 months were 27·3 %, 32·1 %, 37·1 % and 18·7 %, respectively. Multivariate analysis indicated that working mothers (OR = 1·48, 95 % CI 1·16, 1·87; P = 0·001) and mothers who delivered by Caesarean section (OR = 1·95, 95 % CI 1·30, 2·90; P = 0·001) had significantly higher odds for no timely initiation of breast-feeding. Mothers from North West Frontier Province were significantly less likely (OR = 0·37, 95 % CI 0·23, 0·59; P feed their babies exclusively. Mothers delivered by traditional birth attendants had significantly higher odds to predominantly breast-feed their babies (OR = 1·96, 95 % CI 1·18, 3·24; P = 0·009). The odds of being bottle-fed was significantly higher in infants whose mothers had four or more antenatal clinic visits (OR = 1·93, 95 % CI 1·46, 2·55; P feeding practices. To gain the full benefits of breast-feeding for child health and nutrition, there is an urgent need to develop interventions to improve the rates of exclusive breast-feeding.

  3. Genotypic Variation in the Response to Suboptimal Temperature at Different Plant Densities in Cut Chrysanthemum

    NARCIS (Netherlands)

    Ploeg, van der A.; Carvalho, S.M.P.; Heuvelink, E.

    2009-01-01

    Energy efficiency of greenhouse cut chrysanthemum (Chrysanthemum morifolium Ramat.) may be increased by breeding. In addition to breeding for cultivars with a shorter reaction time at suboptimal temperatures, an alternative approach would be to develop cultivars that are heavier at suboptimal

  4. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Kevin L., E-mail: kevinmoore@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Schmidt, Rachel [Department of Physics, Fort Hays State University, Hays, Kansas (United States); Moiseenko, Vitali [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Olsen, Lindsey A.; Tan, Jun [Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri (United States); Xiao, Ying; Galvin, James [Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Pugh, Stephanie [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Seider, Michael J. [Akron City Hospital, Akron, Ohio (United States); Dicker, Adam P. [Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Bosch, Walter; Michalski, Jeff; Mutic, Sasa [Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri (United States)

    2015-06-01

    Purpose: The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. Methods and Materials: A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH{sub 0126,top10%}). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed “high-quality,” “low-quality,” and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Results: Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH{sub 0126,top10%} to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the

  5. Pilot study on the additive effects of berberine and oral type 2 diabetes agents for patients with suboptimal glycemic control

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    Di Pierro F

    2012-07-01

    Full Text Available Francesco Di Pierro,1 Nicola Villanova,2 Federica Agostini,2 Rebecca Marzocchi,2 Valentina Soverini,2 Giulio Marchesini21Scientific Department, Velleja Research, Milano, 2Diseases of Metabolism, S Orsola Malpighi Hospital, Bologna, ItalyBackground: Suboptimal glycemic control is a common situation in diabetes, regardless of the wide range of drugs available to reach glycemic targets. Basic research in diabetes is endeavoring to identify new actives working as insulin savers, use of which could delay the introduction of injectable insulin or reduce the insulin dose needed. Commonly available as a nutraceutical, berberine is a potential candidate.Methods and results: Because its low oral bioavailability can be overcome by P-glycoprotein inhibitors like herbal polyphenols, we have tested the nutraceutical combination of Berberis aristata extract and Silybum marianum extract (Berberol® in type 2 diabetes in terms of its additive effect when combined with a conventional oral regimen for patients with suboptimal glycemic control. After 90 days of treatment, the nutraceutical association had a positive effect on glycemic and lipid parameters, significantly reducing glycosylated hemoglobin, basal insulin, homeostatic model assessment of insulin resistance, total and low-density lipoprotein cholesterol, and triglycerides. A relevant effect was also observed in terms of liver function by measuring aspartate transaminase and alanine transaminase. The product had a good safety profile, with distinctive gastrointestinal side effects likely due to its acarbose-like action.Conclusion: Although further studies should be carried out to confirm our data, Berberol could be considered a good candidate as an adjunctive treatment option in diabetes, especially in patients with suboptimal glycemic control.Keywords: berberine, silymarin, glycosylated hemoglobin, diabetes

  6. Factors associated with suboptimal adherence to antiretroviral therapy in Asia

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    Awachana Jiamsakul

    2014-05-01

    Full Text Available Introduction: Adherence to antiretroviral therapy (ART plays an important role in treatment outcomes. It is crucial to identify factors influencing adherence in order to optimize treatment responses. The aim of this study was to assess the rates of, and factors associated with, suboptimal adherence (SubAdh in the first 24 months of ART in an Asian HIV cohort. Methods: As part of a prospective resistance monitoring study, the TREAT Asia Studies to Evaluate Resistance Monitoring Study (TASER-M collected patients’ adherence based on the World Health Organization-validated Adherence Visual Analogue Scale. SubAdh was defined in two ways: (i 14 days. Time was divided into four intervals: 0–6, 6–12, 12–18 and 18–24 months. Factors associated with SubAdh were analysed using generalized estimating equations. Results: Out of 1316 patients, 32% ever reported 2 assessments per patient per year had an odds ratio (OR=0.7 (95% confidence interval (CI (0.55 to 0.90, p=0.006, compared to sites with ≤2 assessments per patient per year. Compared to heterosexual exposure, SubAdh was higher in injecting drug users (IDUs (OR=1.92, 95% CI (1.23 to 3.00, p=0.004 and lower in homosexual exposure (OR=0.52, 95% CI (0.38 to 0.71, p<0.001. Patients taking a nucleoside transcriptase inhibitor and protease inhibitor (NRTI+PI combination were less likely to report adherence <100% (OR=0.36, 95% CI (0.20 to 0.67, p=0.001 compared to patients taking an NRTI and non-nucleoside transcriptase inhibitor (NRTI+NNRTI combination. SubAdh decreased with increasing time on ART (all p<0.001. Similar associations were found with adherence <95% as the outcome. Conclusions: We found that SubAdh, defined as either <100% and <95%, was associated with mode of HIV exposure, ART regimen, time on ART and frequency of adherence measurement. The more frequently sites assessed patients, the lower the SubAdh, possibly reflecting site resourcing for patient counselling. Although social

  7. A system analysis of a suboptimal surgical experience

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    Richards Michael

    2009-01-01

    Full Text Available Abstract Background System analyses of incidents that occur in the process of health care delivery are rare. A case study of a series of incidents that one of the authors experienced after routine urologic surgery is presented. We interpret the sequence of events as a case of cascading incidents that resulted in outcomes that were suboptimal, although fortunately not fatal. Methods A system dynamics approach was employed to develop illustrative models (flow diagrams of the dynamics of the patient's interaction with surgery and emergency departments. The flow diagrams were constructed based upon the experience of the patient, chart review, discussion with the involved physicians as well as several physician colleagues, comparison of our diagrams with those developed by the hospital of interest for internal planning purposes, and an iterative process with one of the co-authors who is a system dynamics expert. A dynamic hypothesis was developed using insights gained by building the flow diagrams. Results The incidents originated in design flaws and many small innocuous system changes that have occurred incrementally over time, which by themselves may have no consequence but in conjunction with some system randomness can have serious consequences. In the patient's case, the incidents that occurred in preoperative assessment and surgery originated in communication and procedural failures. System delays, communication failures, and capacity issues contributed largely to the subsequent incidents. Some of these issues were controllable by the physicians and staff of the institution, whereas others were less controllable. To the system's credit, some of the more controllable issues were addressed, but systemic problems like overcrowding are unlikely to be addressed in the near future. Conclusion This is first instance that we are aware of in the literature where a system dynamics approach has been used to analyze a patient safety experience. The

  8. A system analysis of a suboptimal surgical experience.

    Science.gov (United States)

    Lee, Robert C; Cooke, David L; Richards, Michael

    2009-01-06

    System analyses of incidents that occur in the process of health care delivery are rare. A case study of a series of incidents that one of the authors experienced after routine urologic surgery is presented. We interpret the sequence of events as a case of cascading incidents that resulted in outcomes that were suboptimal, although fortunately not fatal. A system dynamics approach was employed to develop illustrative models (flow diagrams) of the dynamics of the patient's interaction with surgery and emergency departments. The flow diagrams were constructed based upon the experience of the patient, chart review, discussion with the involved physicians as well as several physician colleagues, comparison of our diagrams with those developed by the hospital of interest for internal planning purposes, and an iterative process with one of the co-authors who is a system dynamics expert. A dynamic hypothesis was developed using insights gained by building the flow diagrams. The incidents originated in design flaws and many small innocuous system changes that have occurred incrementally over time, which by themselves may have no consequence but in conjunction with some system randomness can have serious consequences. In the patient's case, the incidents that occurred in preoperative assessment and surgery originated in communication and procedural failures. System delays, communication failures, and capacity issues contributed largely to the subsequent incidents. Some of these issues were controllable by the physicians and staff of the institution, whereas others were less controllable. To the system's credit, some of the more controllable issues were addressed, but systemic problems like overcrowding are unlikely to be addressed in the near future. This is first instance that we are aware of in the literature where a system dynamics approach has been used to analyze a patient safety experience. The qualitative system dynamics analysis was useful in understanding the

  9. Factors associated with suboptimal adherence to antiretroviral therapy in Asia

    Science.gov (United States)

    Jiamsakul, Awachana; Kumarasamy, Nagalingeswaran; Ditangco, Rossana; Li, Patrick CK; Phanuphak, Praphan; Sirisanthana, Thira; Sungkanuparph, Somnuek; Kantipong, Pacharee; Lee, Christopher KC; Mustafa, Mahiran; Merati, Tuti; Kamarulzaman, Adeeba; Singtoroj, Thida; Law, Matthew

    2014-01-01

    Introduction Adherence to antiretroviral therapy (ART) plays an important role in treatment outcomes. It is crucial to identify factors influencing adherence in order to optimize treatment responses. The aim of this study was to assess the rates of, and factors associated with, suboptimal adherence (SubAdh) in the first 24 months of ART in an Asian HIV cohort. Methods As part of a prospective resistance monitoring study, the TREAT Asia Studies to Evaluate Resistance Monitoring Study (TASER-M) collected patients’ adherence based on the World Health Organization-validated Adherence Visual Analogue Scale. SubAdh was defined in two ways: (i) 14 days. Time was divided into four intervals: 0–6, 6–12, 12–18 and 18–24 months. Factors associated with SubAdh were analysed using generalized estimating equations. Results Out of 1316 patients, 32% ever reported 2 assessments per patient per year had an odds ratio (OR)=0.7 (95% confidence interval (CI) (0.55 to 0.90), p=0.006), compared to sites with ≤2 assessments per patient per year. Compared to heterosexual exposure, SubAdh was higher in injecting drug users (IDUs) (OR=1.92, 95% CI (1.23 to 3.00), p=0.004) and lower in homosexual exposure (OR=0.52, 95% CI (0.38 to 0.71), p<0.001). Patients taking a nucleoside transcriptase inhibitor and protease inhibitor (NRTI+PI) combination were less likely to report adherence <100% (OR=0.36, 95% CI (0.20 to 0.67), p=0.001) compared to patients taking an NRTI and non-nucleoside transcriptase inhibitor (NRTI+NNRTI) combination. SubAdh decreased with increasing time on ART (all p<0.001). Similar associations were found with adherence <95% as the outcome. Conclusions We found that SubAdh, defined as either <100% and <95%, was associated with mode of HIV exposure, ART regimen, time on ART and frequency of adherence measurement. The more frequently sites assessed patients, the lower the SubAdh, possibly reflecting site resourcing for patient counselling. Although social

  10. Moving towards dose individualization of tyrosine kinase inhibitors

    NARCIS (Netherlands)

    Klümpen, Heinz-Josef; Samer, Caroline F.; Mathijssen, Ron H. J.; Schellens, Jan H. M.; Gurney, Howard

    2011-01-01

    Molecular targeted therapies with tyrosine kinase inhibitors (TKIs) have been a recent breakthrough in cancer treatment. These small molecules are mainly used at a fixed dose ignoring the possible need for dose individualization. Fixed dosing may indeed result in suboptimal treatment or excessive

  11. Suboptimal cytoreduction in ovarian carcinoma is associated with molecular pathways characteristic of increased stromal activation.

    Science.gov (United States)

    Liu, Zhenqiu; Beach, Jessica A; Agadjanian, Hasmik; Jia, Dongyu; Aspuria, Paul-Joseph; Karlan, Beth Y; Orsulic, Sandra

    2015-12-01

    Suboptimal cytoreductive surgery in advanced epithelial ovarian cancer (EOC) is associated with poor survival but it is unknown if poor outcome is due to the intrinsic biology of unresectable tumors or insufficient surgical effort resulting in residual tumor-sustaining clones. Our objective was to identify the potential molecular pathway(s) and cell type(s) that may be responsible for suboptimal surgical resection. By comparing gene expression in optimally and suboptimally cytoreduced patients, we identified a gene network associated with suboptimal cytoreduction and explored the biological processes and cell types associated with this gene network. We show that primary tumors from suboptimally cytoreduced patients express molecular signatures that are typically present in a distinct molecular subtype of EOC characterized by increased stromal activation and lymphovascular invasion. Similar molecular pathways are present in EOC metastases, suggesting that primary tumors in suboptimally cytoreduced patients are biologically similar to metastatic tumors. We demonstrate that the suboptimal cytoreduction network genes are enriched in reactive tumor stroma cells rather than malignant tumor cells. Our data suggest that the success of cytoreductive surgery is dictated by tumor biology, such as extensive stromal reaction and increased invasiveness, which may hinder surgical resection and ultimately lead to poor survival. Copyright © 2015. Published by Elsevier Inc.

  12. Cost-effectiveness of extended-release methylphenidate in children and adolescents with attention-deficit/hyperactivity disorder sub-optimally treated with immediate release methylphenidate.

    Directory of Open Access Journals (Sweden)

    Jurjen van der Schans

    Full Text Available Attention-Deficit/Hyperactivity Disorder (ADHD is a common psychiatric disorder in children and adolescents. Immediate-release methylphenidate (IR-MPH is the medical treatment of first choice. The necessity to use several IR-MPH tablets per day and associated potential social stigma at school often leads to reduced compliance, sub-optimal treatment, and therefore economic loss. Replacement of IR-MPH with a single-dose extended release (ER-MPH formulation may improve drug response and economic efficiency.To evaluate the cost-effectiveness from a societal perspective of a switch from IR-MPH to ER-MPH in patients who are sub-optimally treated.A daily Markov-cycle model covering a time-span of 10 years was developed including four different health states: (1 optimal response, (2 sub-optimal response, (3 discontinued treatment, and (4 natural remission. ER-MPH options included methylphenidate osmotic release oral system (MPH-OROS and Equasym XL/Medikinet CR. Both direct costs and indirect costs were included in the analysis, and effects were expressed as quality-adjusted life years (QALYs. Univariate, multivariate as well as probabilistic sensitivity analysis were conducted and the main outcomes were incremental cost-effectiveness ratios.Switching sub-optimally treated patients from IR-MPH to MPH-OROS or Equasym XL/Medikinet CR led to per-patient cost-savings of €4200 and €5400, respectively, over a 10-year treatment span. Sensitivity analysis with plausible variations of input parameters resulted in cost-savings in the vast majority of estimations.This study lends economic support to switching patients with ADHD with suboptimal response to short-acting IR-MPH to long-acting ER-MPH regimens.

  13. Cost-effectiveness of extended-release methylphenidate in children and adolescents with attention-deficit/hyperactivity disorder sub-optimally treated with immediate release methylphenidate.

    Science.gov (United States)

    van der Schans, Jurjen; Kotsopoulos, Nikos; Hoekstra, Pieter J; Hak, Eelko; Postma, Maarten J

    2015-01-01

    Attention-Deficit/Hyperactivity Disorder (ADHD) is a common psychiatric disorder in children and adolescents. Immediate-release methylphenidate (IR-MPH) is the medical treatment of first choice. The necessity to use several IR-MPH tablets per day and associated potential social stigma at school often leads to reduced compliance, sub-optimal treatment, and therefore economic loss. Replacement of IR-MPH with a single-dose extended release (ER-MPH) formulation may improve drug response and economic efficiency. To evaluate the cost-effectiveness from a societal perspective of a switch from IR-MPH to ER-MPH in patients who are sub-optimally treated. A daily Markov-cycle model covering a time-span of 10 years was developed including four different health states: (1) optimal response, (2) sub-optimal response, (3) discontinued treatment, and (4) natural remission. ER-MPH options included methylphenidate osmotic release oral system (MPH-OROS) and Equasym XL/Medikinet CR. Both direct costs and indirect costs were included in the analysis, and effects were expressed as quality-adjusted life years (QALYs). Univariate, multivariate as well as probabilistic sensitivity analysis were conducted and the main outcomes were incremental cost-effectiveness ratios. Switching sub-optimally treated patients from IR-MPH to MPH-OROS or Equasym XL/Medikinet CR led to per-patient cost-savings of €4200 and €5400, respectively, over a 10-year treatment span. Sensitivity analysis with plausible variations of input parameters resulted in cost-savings in the vast majority of estimations. This study lends economic support to switching patients with ADHD with suboptimal response to short-acting IR-MPH to long-acting ER-MPH regimens.

  14. Suboptimal care and maternal mortality among foreign-born women in Sweden

    DEFF Research Database (Denmark)

    Esscher, Annika; Binder-Finnema, Pauline; Bødker, Birgit

    2014-01-01

    BACKGROUND: Several European countries report differences in risk of maternal mortality between immigrants from low- and middle-income countries and host country women. The present study identified suboptimal factors related to care-seeking, accessibility, and quality of care for maternal deaths...... language and suboptimal interpreter system or usage. Inadequate care occurred more often among the foreign-born (p = 0.04), whereas delays in consultation/referral and miscommunication between health care providers where equally common between the two groups. CONCLUSIONS: Suboptimal care factors, major...

  15. Patterns of marijuana and tobacco use associated with suboptimal self-rated health among US adult ever users of marijuana

    Directory of Open Access Journals (Sweden)

    James Tsai

    2017-06-01

    In conclusion, among adult ever users of marijuana, current tobacco use is high and strongly associated with suboptimal SRH; regular marijuana smoking with or without current tobacco use is significantly associated with suboptimal SRH.

  16. Effect of Using Suboptimal Alignments in Template-Based Protein Structure Prediction

    Science.gov (United States)

    Chen, Hao; Kihara, Daisuke

    2010-01-01

    Computational protein structure prediction remains a challenging task in protein bioinformatics. In the recent years, the importance of template-based structure prediction is increasing due to the growing number of protein structures solved by the structural genomics projects. To capitalize the significant efforts and investments paid on the structural genomics projects, it is urgent to establish effective ways to use the solved structures as templates by developing methods for exploiting remotely related proteins that cannot be simply identified by homology. In this work, we examine the effect of employing suboptimal alignments in template-based protein structure prediction. We showed that suboptimal alignments are often more accurate than the optimal one, and such accurate suboptimal alignments can occur even at a very low rank of the alignment score. Suboptimal alignments contain a significant number of correct amino acid residue contacts. Moreover, suboptimal alignments can improve template-based models when used as input to Modeller. Finally, we employ suboptimal alignments for handling a contact potential in a probabilistic way in a threading program, SUPRB. The probabilistic contacts strategy outperforms the partly thawed approach which only uses the optimal alignment in defining residue contacts and also the reranking strategy, which uses the contact potential in reranking alignments. The comparison with existing methods in the template-recognition test shows that SUPRB is very competitive and outperform existing methods. PMID:21058297

  17. Suboptimal asthma care for immigrant children: results of an audit study

    Directory of Open Access Journals (Sweden)

    Klazinga Niek S

    2008-01-01

    Full Text Available Abstract Background Little is known on the scope and nature of ethnic inequalities in suboptimal asthma care for children. This study aimed to assess (1 ethnic differences in suboptimal asthma care for children with an asthma exacerbation who consulted a physician, and (2 ethnic differences in the nature of suboptimal care. Methods All children aged 6–16 years who during a period of six months consulted the paediatric department of the Academic Medical Centre-University of Amsterdam or one of the six regional primary care centres with an asthma exacerbation were included. Clinical guidelines were systematically converted to review criteria following the strategy as proposed by the Agency for Health Care Policy and Research. Based upon these review criteria and their experience experts of two multidisciplinary panels retrospectively assessed the quality of care and its (possible failure to prevent the occurrence of asthma exacerbation. Results Only a small number of children (n = 35 were included in the analysis as a result of which the ethnic differences in suboptimal care were not significant. However, the results do indicate immigrant children, in particular 'other non-Western' children (n = 11, more frequently to receive suboptimal care related to the asthma exacerbation when compared to ethnic Dutch children. Furthermore, we found the nature of suboptimal care to differ with under-prescribing in the 'other non-Western' group (n = 11, lack of information exchange between physicians in the Surinamese/Antillean group (n = 12 and lack of education, and counselling of patients and parents in the ethnic Dutch (n = 12 as the most relevant factor. Conclusion Ethnic inequalities in the scope and nature of suboptimal asthma care for children in the Netherlands seem to exist. For the non-western immigrant groups the results indicate the importance of the prescription behaviour of the medical doctor, as well as the supervision by one health care

  18. Suboptimal maternal and paternal mental health are associated with child bullying perpetration.

    Science.gov (United States)

    Shetgiri, Rashmi; Lin, Hua; Flores, Glenn

    2015-06-01

    This study examines associations between maternal and paternal mental health and child bullying perpetration among school-age children, and whether having one or both parents with suboptimal mental health is associated with bullying. The 2007 National Survey of Children's Health, a nationally-representative, random-digit-dial survey, was analyzed, using a parent-reported bullying measure. Suboptimal mental health was defined as fair/poor (vs. good/very good/excellent) parental self-reported mental and emotional health. Of the 61,613 parents surveyed, more than half were parents of boys and were white, 20% were Latino, 15% African American, and 7% other race/ethnicity. Suboptimal maternal (OR 1.4; 95% CI 1.1-1.8) and paternal (OR 1.5; 95% CI 1.1-2.2) mental health are associated with bullying. Compared with children with no parents with suboptimal mental health, children with only one or both parents with suboptimal mental health have higher bullying odds. Addressing the mental health of both parents may prove beneficial in preventing bullying.

  19. Not Noisy, Just Wrong: The Role of Suboptimal Inference in Behavioral Variability

    Science.gov (United States)

    Beck, Jeffrey M.; Ma, Wei Ji; Pitkow, Xaq; Latham, Peter E.; Pouget, Alexandre

    2015-01-01

    Behavior varies from trial to trial even when the stimulus is maintained as constant as possible. In many models, this variability is attributed to noise in the brain. Here, we propose that there is another major source of variability: suboptimal inference. Importantly, we argue that in most tasks of interest, and particularly complex ones, suboptimal inference is likely to be the dominant component of behavioral variability. This perspective explains a variety of intriguing observations, including why variability appears to be larger on the sensory than on the motor side, and why our sensors are sometimes surprisingly unreliable. PMID:22500627

  20. Frequency and predictors of suboptimal glycemic control in an African diabetic population

    Directory of Open Access Journals (Sweden)

    Kibirige D

    2017-02-01

    Full Text Available Davis Kibirige,1 George Patrick Akabwai,2 Leaticia Kampiire,3 Daniel Ssekikubo Kiggundu,4 William Lumu5 1Department of Medicine/Diabetic and Hypertension Clinics, Our Lady of Consolota Hospital, Kisubi, 2Baylor College of Medicine, Children’s Foundation, 3Infectious Diseases Research Collaboration, Kampala, 4Nephrology Unit, Mulago National Referral and Teaching Hospital, Kampala, 5Department of Medicine and Diabetes/Endocrine Unit, Mengo Hospital, Mengo, Uganda Background: Persistent suboptimal glycemic control is invariably associated with onset and progression of acute and chronic diabetic complications in diabetic patients. In Uganda, studies documenting the magnitude and predictors of suboptimal glycemic control in adult ambulatory diabetic patients are limited. This study aimed at determining the frequency and predictors of suboptimal glycemic control in adult diabetic patients attending three urban outpatient diabetic clinics in Uganda. Methods: In this hospital-based cross-sectional study, eligible ambulatory adult diabetic patients attending outpatient diabetic clinics of three urban hospitals were consecutively enrolled over 11 months. Suboptimal glycemic control was defined as glycated hemoglobin (HbA1c level ≥7%. Multivariable analysis was applied to determine the predictors. Results: The mean age of the study participants was 52.2±14.4 years, and the majority of them were females (283, 66.9%. The median (interquartile range HbA1c level was 9% (6.8%–12.4%. Suboptimal glycemic control was noted in 311 study participants, accounting for 73.52% of the participants. HbA1c levels of 7%–8%, 8.1%–9.9%, and ≥10% were noted in 56 (13.24%, 76 (17.97%, and 179 (42.32% study participants, respectively. The documented predictors of suboptimal glycemic control were metformin monotherapy (odds ratio: 0.36, 95% confidence interval: 0.21–0.63, p<0.005 and insulin therapy (odds ratio: 2.41, 95% confidence interval: 1.41–4.12, p=0

  1. Are theoretical perspectives useful to explain nurses' tolerance of suboptimal care?

    Science.gov (United States)

    Price, Lesley; Duffy, Kathleen; McCallum, Jacqueline; Ness, Valerie

    2015-10-01

    This paper explores two theoretical perspectives that may help nurse managers understand why staff tolerate suboptimal standards of care. Standards of care have been questioned in relation to adverse events and errors for some years in health care across the western world. More recently, the focus has shifted to inadequate nursing standards with regard to care and compassion, and a culture of tolerance by staff to these inadequate standards. The theories of conformity and cognitive dissonance are analysed to investigate their potential for helping nurse managers to understand why staff tolerate suboptimal standards of care. The literature suggests that nurses appear to adopt behaviours consistent with the theory of conformity and that they may accept suboptimal care to reduce their cognitive dissonance. Nurses may conform to be accepted by the team. This may be confounded by nurses rationalising their care to reduce the cognitive dissonance they feel. The investigation into the Mid Staffordshire National Health Service called for a change in culture towards transparency, candidness and openness. Providing insights as to why some nursing staff tolerate suboptimal care may provide a springboard to allow nurse managers to consider the complexities surrounding this required transformation. © 2014 John Wiley & Sons Ltd.

  2. Influence of sub-optimal temperature on tomato growth and yield : a review

    NARCIS (Netherlands)

    Ploeg, van der A.; Heuvelink, E.

    2005-01-01

    The effects of temperature on growth, development and yield of tomato (Lycopersicon esculentum) are reviewed with special emphasis on cultivar differences. The focus is on sub-optimal temperatures, above the level where chilling injury occurs. Temperature has a large effect on all aspects of

  3. Suboptimal decision making by children with ADHD in the face of risk

    DEFF Research Database (Denmark)

    Sørensen, Lin; Sonuga-Barke, Edmund; Eichele, Heike

    2017-01-01

    Objective: Suboptimal decision making in the face of risk (DMR) in children with attention-deficit hyperactivity disorder (ADHD) may be mediated by deficits in a number of different neuropsychological processes. We investigated DMR in children with ADHD using the Cambridge Gambling Task (CGT...

  4. High Current CD4+ T Cell Count Predicts Suboptimal Adherence to Antiretroviral Therapy

    NARCIS (Netherlands)

    Pasternak, Alexander O.; de Bruin, Marijn; Bakker, Margreet; Berkhout, Ben; Prins, Jan M.

    2015-01-01

    High levels of adherence to antiretroviral therapy (ART) are necessary for achieving and maintaining optimal virological suppression, as suboptimal adherence leads to therapy failure and disease progression. It is well known that adherence to ART predicts therapy response, but it is unclear whether

  5. Indicators of suboptimal performance embedded in the Wechsler Memory Scale : Fourth Edition (WMS-IV)

    NARCIS (Netherlands)

    Bouman, Z.; Hendriks, M.P.H.; Schmand, B.A.; Kessels, R.P.C.; Aldenkamp, A.P.

    2016-01-01

    INTRODUCTION: Recognition and visual working memory tasks from the Wechsler Memory Scale-Fourth Edition (WMS-IV) have previously been documented as useful indicators for suboptimal performance. The present study examined the clinical utility of the Dutch version of the WMS-IV (WMS-IV-NL) for the

  6. High current CD4+ T cell count predicts suboptimal adherence to antiretroviral therapy

    NARCIS (Netherlands)

    Pasternak, A.O.; de Bruin, M.; Bakker, M.; Berkhout, B.; Prins, J.M.

    2015-01-01

    High levels of adherence to antiretroviral therapy (ART) are necessary for achieving and maintaining optimal virological suppression, as suboptimal adherence leads to therapy failure and disease progression. It is well known that adherence to ART predicts therapy response, but it is unclear whether

  7. State Space Formulas for a Solution of the Suboptimal Nehari Problem on the Unit Disc

    NARCIS (Netherlands)

    Curtain, Ruth F.; Opmeer, Mark R.

    We give state space formulas for a ("central") solution of the suboptimal Nehari problem for functions defined on the unit disc and taking values in the space of bounded operators in separable Hilbert spaces. Instead of assuming exponential stability, we assume a weaker stability concept (the

  8. Sub-optimal birth weight in newborns of a high socioeconomic status population

    Directory of Open Access Journals (Sweden)

    Conceição Aparecida de Mattos Segre

    2008-09-01

    Full Text Available Objective: To compare sub-optimal birth weight (2,500 to 2,999 g term newborns to appropriate for gestational age (birth weight ≥ 3,000 g term newborns, regarding maternal data and newborn morbidity and mortality. Methods: Single term newborns, appropriate for gestational age from a high socioeconomic population (n = 1,242 with birth weight ranging from 2,500 to 2,999 g (Group I were compared to 4,907 newborns with birth weight ≥ than 3,000 g (Group II. Maternal and newborn characteristics were compared between the groups. The Mann-Whitney test, χ2 test and multivariate analysis were used. The significance level adopted was p < 0.05. Rresults: The frequency of sub-optimal birth weight newborns in the population studied was 20.2%. There was a significant association between sub-optimal birth weight and maternal weight before pregnancy and body mass index, maternal weight gain, height, smoking habit and hypertension. Newborns’ 1-minute Apgar score, neonatal hypoglycemia, jaundice, transient tachypnea, congenital pneumonia and hospital stay were significantly different between the groups (p < 0.05. A significant relationship could not be established with the 5-minute Apgar score and pulmonary hypertension in both groups. Neonatal mortality did not differ between the groups. Cconclusions: Socioeconomic status was not a risk factor for sub-optimal birth weight in the studied population. Genetic and environmental factors were associated to sub-optimal weight and neonatal diseases. According to these data, this group of newborns should receive special attention from the health team.

  9. A non-destructive selection method for faster growth at suboptimal temperature in common bean (Phaseolus vulgaris)

    NARCIS (Netherlands)

    Drijfhout, E.; Oeveren, J.C. van; Jansen, R.C.

    1991-01-01

    A non-destructive method has been developed to select common bean (Phaseolus vulgaris L.) plants whose growth is less effected at a suboptimal temperature. Shoot weight was determined at a suboptimal (14°C) and optimal temperature (20°C), 38 days after sowing and accessions identified with a

  10. Statin therapy reduces the likelihood of suboptimal blood pressure control among Ugandan adult diabetic patients

    Directory of Open Access Journals (Sweden)

    Lumu W

    2017-02-01

    Full Text Available William Lumu,1 Leaticia Kampiire,2 George Patrick Akabwai,3 Daniel Ssekikubo Kiggundu,4 Davis Kibirige5 1Department of Medicine and Diabetes/Endocrine Unit, Mengo Hospital, 2Infectious Disease Research Collaboration, 3Baylor College of Medicine Children’s Foundation, 4Nephrology Unit, Mulago National Referral and Teaching Hospital, 5Department of Medicine, Uganda Martyrs Hospital Lubaga, Kampala, Uganda Background: Hypertension is one of the recognized risk factors of cardiovascular diseases in adult diabetic patients. High prevalence of suboptimal blood pressure (BP control has been well documented in the majority of studies assessing BP control in diabetic patients in sub-Saharan Africa. In Uganda, there is a dearth of similar studies. This study evaluated the prevalence and correlates of suboptimal BP control in an adult diabetic population in Uganda.Patients and methods: This was a cross-sectional study that enrolled 425 eligible ambulatory adult diabetic patients attending three urban diabetic outpatient clinics over 11 months. Data about their sociodemographic characteristics and clinical history were collected using pre-tested questionnaires. Suboptimal BP control was defined according to the 2015 American Diabetes Association standards of diabetes care guideline as BP levels ≥140/90 mmHg.Results: The mean age of the study participants was 52.2±14.4 years, with the majority being females (283, 66.9%. Suboptimal BP control was documented in 192 (45.3% study participants and was independently associated with the study site (private hospitals; odds ratio 2.01, 95% confidence interval 1.18–3.43, P=0.01 and use of statin therapy (odds ratio 0.5, 95% confidence interval 0.26–0.96, P=0.037.Conclusion: Suboptimal BP control was highly prevalent in this study population. Strategies to improve optimal BP control, especially in the private hospitals, and the use of statin therapy should be encouraged in adult diabetic patients

  11. Peptide Suboptimal Conformation Sampling for the Prediction of Protein-Peptide Interactions.

    Science.gov (United States)

    Lamiable, Alexis; Thévenet, Pierre; Eustache, Stephanie; Saladin, Adrien; Moroy, Gautier; Tuffery, Pierre

    2017-01-01

    The blind identification of candidate patches of interaction on the protein surface is a difficult task that can hardly be accomplished without a heuristic or the use of simplified representations to speed up the search. The PEP-SiteFinder protocol performs a systematic blind search on the protein surface using a rigid docking procedure applied to a limited set of peptide suboptimal conformations expected to approximate satisfactorily the conformation of the peptide in interaction. All steps rely on a coarse-grained representation of the protein and the peptide. While simple, such a protocol can help to infer useful information, assuming a critical analysis of the results. Moreover, such a protocol can be extended to a semi-flexible protocol where the suboptimal conformations are directly folded in the vicinity of the receptor.

  12. A convex programming framework for optimal and bounded suboptimal well field management

    DEFF Research Database (Denmark)

    Dorini, Gianluca Fabio; Thordarson, Fannar Ørn; Bauer-Gottwein, Peter

    2012-01-01

    are often convex, hence global optimality can be attained by a wealth of algorithms. Among these, the Interior Point methods are extensively employed for practical applications, as they are capable of efficiently solving large-scale problems. Despite this, management models explicitly embedding both systems...... without simplifications are rare, and they usually involve heuristic techniques. The main limitation with heuristics is that neither optimality nor suboptimality bounds can be guarantee. This paper extends the proof of convexity to mixed management models, enabling the use of Interior Point techniques...... to compute globally optimal management solutions. If convexity is not achieved, it is shown how suboptimal solutions can be computed, and how to bind their deviation from the optimality. Experimental results obtained by testing the methodology in a well field located nearby Copenhagen (DK), show...

  13. Suboptimal investments and M&A deals in emerging capital markets

    Directory of Open Access Journals (Sweden)

    Cherkasova Victoria

    2016-01-01

    Full Text Available This paper focuses on the efficiency of target-company investment decisions before and after Merger & Acquisition deals. We study whether M&A deals help to solve the problem of suboptimal investment after the acquisition. Using a sample of 145 target companies from BRICS countries that were acquired during the period 2004-2014, we outline those that had over- or underinvested before the deal and show that more than half the companies managed to optimize the investment level after the deal. We determine the key factors that improve the inefficiency of investment decisions and demonstrate that the industry and country have an impact on the degree of suboptimal investment.

  14. Self-care practices of Malaysian adults with diabetes and sub-optimal glycaemic control.

    Science.gov (United States)

    Tan, Ming Yeong; Magarey, Judy

    2008-08-01

    To investigate the self-care practices of Malaysian adults with diabetes and sub-optimal glycaemic control. Using a one-to-one interviewing approach, data were collected from 126 diabetic adults from four settings. A 75-item questionnaire was used to assess diabetes-related knowledge and self-care practices regarding, diet, medication, physical activity and self-monitoring of blood glucose (SMBG). Most subjects had received advice on the importance of self-care in the management of their diabetes and recognised its importance. Sixty-seven subjects (53%) scored below 50% in their diabetes-related knowledge. Subjects who consumed more meals per day (80%), or who did not include their regular sweetened food intakes in their daily meal plan (80%), or who were inactive in daily life (54%), had higher mean fasting blood glucose levels (p=0.04). Subjects with medication non-adherence (46%) also tended to have higher fasting blood glucose levels. Only 15% of the subjects practiced SMBG. Predictors of knowledge deficit and poor self-care were low level of education (p = practices among the majority of diabetic patients with sub-optimal glycaemic control. This study should contribute to the development of effective education strategies to promote health for adults with sub-optimal diabetes control.

  15. Comparative Performance Analysis of G-RAKE Receivers with Suboptimal Finger Placement

    Directory of Open Access Journals (Sweden)

    K. B. Baltzis

    2014-07-01

    Full Text Available Generalized RAKE (G-RAKE reception reduces the total amount of interference and provides enhanced diversity by comprising extra fingers to collect information about interference and further using channel and impairment correlation estimates for fingers allocation. However, the hardware complexity and the excessive computational requirements of GRAKE receivers may restrict their application in real systems; thus, suboptimal solutions are commonly used. In this paper, we propose and evaluate three maximum likelihood G-RAKE structures for colored noise with suboptimal finger placement. In all implementations, the fingers are optimally distributed within a time window that spans from several chip periods before the first arriving multipath to several chip periods after the latest one. The first receiver has its fingers at integer multiples of the chip period while in the rest two structures the search window is segmented in halves and tenths of the chip duration. This work also extends earlier studies by thoroughly investigating the impact of fractionally spaced finger placement on system performance. Our analysis shows that a suboptimal finger allocation reduces hardware complexity with negligible performance loss. The impact of channel delay spread and processing gain on system performance is also investigated and gives interesting results.

  16. Weighted Implementation of Suboptimal Paths (WISP): An Optimized Algorithm and Tool for Dynamical Network Analysis.

    Science.gov (United States)

    Van Wart, Adam T; Durrant, Jacob; Votapka, Lane; Amaro, Rommie E

    2014-02-11

    Allostery can occur by way of subtle cooperation among protein residues (e.g., amino acids) even in the absence of large conformational shifts. Dynamical network analysis has been used to model this cooperation, helping to computationally explain how binding to an allosteric site can impact the behavior of a primary site many ångstroms away. Traditionally, computational efforts have focused on the most optimal path of correlated motions leading from the allosteric to the primary active site. We present a program called Weighted Implementation of Suboptimal Paths (WISP) capable of rapidly identifying additional suboptimal pathways that may also play important roles in the transmission of allosteric signals. Aside from providing signal redundancy, suboptimal paths traverse residues that, if disrupted through pharmacological or mutational means, could modulate the allosteric regulation of important drug targets. To demonstrate the utility of our program, we present a case study describing the allostery of HisH-HisF, an amidotransferase from T. maritima thermotiga. WISP and its VMD-based graphical user interface (GUI) can be downloaded from http://nbcr.ucsd.edu/wisp.

  17. Sub-optimal MCV Cover Based Method for Measuring Fractal Dimension

    Energy Technology Data Exchange (ETDEWEB)

    Tolle, Charles Robert; McJunkin, Timothy R; Gorsich, D. I.

    2003-01-01

    A new method for calculating fractal dimension is developed in this paper. The method is based on the box dimension concept; however, it involves direct estimation of a suboptimal covering of the data set of interest. By finding a suboptimal cover, this method is better able to estimate the required number of covering elements for a given cover size than is the standard box counting algorithm. Moreover, any decrease in the error of the covering element count directly increases the accuracy of the fractal dimension estimation. In general, our method represents a mathematical dual to the standard box counting algorithm by not solving for the number of boxes used to cover a data set given the size of the box. Instead, the method chooses the number of covering elements and then proceeds to find the placement of smallest hyperellipsoids that fully covers the data set. This method involves a variant of the Fuzzy-C Means clustering algorithm, as well as the use of the Minimum Cluster Volume clustering algorithm. A variety of fractal dimension estimators using this suboptimal covering method are discussed. Finally, these methods are compared to the standard box counting algorithm and wavelet-decomposition methods for calculating fractal dimension by using one-dimensional cantor dust sets and a set of standard Brownian random fractal images.

  18. When the learning environment is suboptimal: exploring medical students' perceptions of "mistreatment".

    Science.gov (United States)

    Gan, Runye; Snell, Linda

    2014-04-01

    Despite widespread implementation of policies to address mistreatment, high rates of mistreatment during clinical training are reported, prompting the question of whether "mistreatment" means more to students than delineated in official codes of conduct. Understanding "mistreatment" from students' perspective and as it relates to the learning environment is needed before effective interventions can be implemented. The authors conducted focus groups with final-year medical students at McGill University Faculty of Medicine in 2012. Participants were asked to characterize "suboptimal learning experience" and "mistreatment." Transcripts were analyzed via inductive thematic analysis. Forty-one of 174 eligible students participated in six focus groups. Students described "mistreatment" as lack of respect or attack directed toward the person, and "suboptimal learning experience" as that which compromised their learning. Differing perceptions emerged as students debated whether "mistreatment" can be applied to negative learning environments as well as isolated incidents of mistreatment even though some experiences fell outside of the "official" label as per institutional policies. Whether students perceived "mistreatment" versus a "suboptimal learning experience" in negative environments appeared to be influenced by several key factors. A concept map integrating these ideas is presented. How students perceived negative situations during training appears to be a complex process. When medical students say "mistreatment," they may be referring to a spectrum, with incident-based mistreatment on one end and learning-environment-based mistreatment on the other. Multiple factors influenced how students perceived an environment-based negative situation and may provide strategies to improving the learning environment.

  19. Single immunization with a suboptimal antigen dose encapsulated into polyanhydride microparticles promotes high titer and avid antibody responses

    Science.gov (United States)

    Microparticle adjuvants based on biodegradable polyanhydrides were used to provide controlled delivery of a model antigen, ovalbumin (Ova), to mice. Ova was encapsulated into two different polyanhydride microparticle formulations to evaluate the influence of polymer chemistry on the nature and magn...

  20. Real-World Dosing Patterns of Atomoxetine in Adults with Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Kabul, Samaneh; Alatorre, Carlos; Montejano, Leslie B; Farr, Amanda M; Clemow, David B

    2015-12-01

    The aim was to investigate the dosing patterns of atomoxetine monotherapy in adult patients with attention-deficit/hyperactivity disorder (ADHD) in a retrospective analysis. Adult (≥ 18 years) patients with ADHD newly initiated on atomoxetine with ≥ 1 outpatient pharmacy claim for atomoxetine between January 2006 and December 2011 were selected from the Truven Health MarketScan(®) Commercial database. After a 30-day titration period, dosing patterns of atomoxetine monotherapy were analyzed in the 12 months following initiation. In addition, patient demographic and clinical characteristics were compared to identify characteristics associated with suboptimal versus recommended dosing. Of the 12,412 adult patients with ADHD newly initiated on atomoxetine, 4548 (36.6%) were suboptimally dosed, whereas 3323 (26.7%) were treated at recommended dose. Overall, study patients were treated at a mean (standard deviation [SD]) dose of 68.5 (44.9) mg/day. The suboptimal dosing cohort included significantly more females (54% vs. 44%, P < 0.001) and had fewer patients with pre-index use of other ADHD medications (17% vs. 20%, P < 0.001) compared with the recommended dosing cohort. Adult patients with ADHD receiving atomoxetine therapy in a real-world setting are often dosed suboptimally. Increasing the awareness on optimal dosing strategy among clinicians and patients is warranted to maximize the therapeutic benefits of atomoxetine among adult patients with ADHD. © 2015 Eli Lilly and Company. CNS Neuroscience and Therapeutics published by John Wiley & Sons Ltd.

  1. Outcome of the sub-optimal dialysis starter on peritoneal dialysis. Report from the French Language Peritoneal Dialysis Registry (RDPLF).

    Science.gov (United States)

    Lobbedez, Thierry; Verger, Christian; Ryckelynck, Jean-Philippe; Fabre, Emmanuel; Evans, David

    2013-05-01

    This study was carried out to examine the association of sub-optimal dialysis initiation of peritoneal dialysis (PD) with all the possible outcomes on PD using survival analysis in the presence of competing risks. This was a retrospective cohort study based on the data of the French Language Peritoneal Dialysis Registry. We analysed 8527 incident patients starting PD between January 2002 and December 2010. The end of the observation period was 01 June 2011. Times from the start of PD to death, transplantation, transfer to haemodialysis (HD) and first peritonitis episode were calculated. The sub-optimal dialysis initiation was defined by a period of <30 days on HD before PD initiation. Among 8527 patients, there were 568 patients who started PD after <30 days on HD. There were 6562 events: 3078 deaths, 2136 transfers to HD, 1348 renal transplantations. When using a Fine and Gray model, sub-optimal dialysis start, early peritonitis and transplant failure were associated with a higher sub-distribution relative hazard of technique failure. There was no association between the sub-optimal dialysis start and the sub-distribution hazard of death or transplantation. In the multivariate analysis using a Fine and Gray regression model, the sub-optimal dialysis start was not associated with a higher sub distribution relative hazard of peritonitis. Sub-optimal dialysis initiation is neither associated with a higher risk of death nor with a lower risk of renal transplantation. Sub-optimal PD patients had a higher risk of transfer to HD.

  2. A low-volume polyethylene glycol solution was associated with an increased suboptimal bowel preparation rate but had similar recommendations for an early repeat colonoscopy, procedure times, and adenoma detection rates.

    Directory of Open Access Journals (Sweden)

    Sam C Hankins

    Full Text Available Low-volume polyethylene glycol (PEG bowel preparations are better tolerated by patients than high-volume preparations and may achieve similar preparation quality. However, there is little data comparing their effects on a recommendation for an early repeat colonoscopy (because of a suboptimal preparation, procedure times, adenoma detection rate (ADR, and advanced adenoma detection rate (AADR.This is a retrospective cohort study of outpatient colonoscopies performed during a one-year period at a single academic medical center in which low-volume MoviPrep® (n = 1841 or high-volume Colyte® (n = 1337 was used. All preparations were split-dosed. Appropriate covariates were included in regression models assessing suboptimal preparation quality (fair, poor, or inadequate, procedure times, recommendation for an early repeat colonoscopy, ADR, and AADR.MoviPrep® was associated with an increase in having a suboptimal bowel preparation (OR 1.36; 95% CI: 1.06-1.76, but it was not associated with differences in insertion (p = 0.43, withdrawal (p = 0.22, or total procedure times (p = 0.10. The adjusted percentage with a suboptimal preparation was 11.7% for patients using MoviPrep® and 8.8% for patients using Colyte®. MoviPrep® was not associated with a significant difference in overall ADR (OR 0.93; 95% CI: 0.78-1.11, AADR (OR 1.18; 95% CI: 0.87-1.62, or recommendation for early repeat colonoscopy (OR 1.16; 95% CI: 0.72-1.88.MoviPrep® was associated with a small absolute increase in having a suboptimal preparation, but did not affect recommendations for an early repeat colonoscopy, procedure times, or adenoma detection rates. Mechanisms to reduce financial barriers limiting low-volume preparations should be considered because of their favorable tolerability profile.

  3. Quantitative effect of suboptimal codon usage on translational efficiency of mRNA encoding HIV-1 gag in intact T cells.

    Directory of Open Access Journals (Sweden)

    Kholiswa C Ngumbela

    Full Text Available BACKGROUND: The sequences of wild-isolate strains of Human Immunodeficiency Virus-1 (HIV-1 are characterized by low GC content and suboptimal codon usage. Codon optimization of DNA vectors can enhance protein expression both by enhancing translational efficiency, and by altering RNA stability and export. Although gag codon optimization is widely used in DNA vectors and experimental vaccines, the actual effect of altered codon usage on gag translational efficiency has not been quantified. METHODOLOGY AND PRINCIPAL FINDINGS: To quantify translational efficiency of gag mRNA in live T cells, we transfected Jurkat cells with increasing doses of capped, polyadenylated synthetic mRNA corresponding to wildtype or codon-optimized gag sequences, measured Gag production by quantitative ELISA and flow cytometry, and estimated the translational efficiency of each transcript as pg of Gag antigen produced per microg of input mRNA. We found that codon optimization yielded a small increase in gag translational efficiency (approximately 1.6 fold. In contrast when cells were transfected with DNA vectors requiring nuclear transcription and processing of gag mRNA, codon optimization resulted in a very large enhancement of Gag production. CONCLUSIONS: We conclude that suboptimal codon usage by HIV-1 results in only a slight loss of gag translational efficiency per se, with the vast majority of enhancement in protein expression from DNA vectors due to altered processing and export of nuclear RNA.

  4. Quantitative effect of suboptimal codon usage on translational efficiency of mRNA encoding HIV-1 gag in intact T cells.

    Science.gov (United States)

    Ngumbela, Kholiswa C; Ryan, Kieran P; Sivamurthy, Rohini; Brockman, Mark A; Gandhi, Rajesh T; Bhardwaj, Nina; Kavanagh, Daniel G

    2008-06-04

    The sequences of wild-isolate strains of Human Immunodeficiency Virus-1 (HIV-1) are characterized by low GC content and suboptimal codon usage. Codon optimization of DNA vectors can enhance protein expression both by enhancing translational efficiency, and by altering RNA stability and export. Although gag codon optimization is widely used in DNA vectors and experimental vaccines, the actual effect of altered codon usage on gag translational efficiency has not been quantified. To quantify translational efficiency of gag mRNA in live T cells, we transfected Jurkat cells with increasing doses of capped, polyadenylated synthetic mRNA corresponding to wildtype or codon-optimized gag sequences, measured Gag production by quantitative ELISA and flow cytometry, and estimated the translational efficiency of each transcript as pg of Gag antigen produced per microg of input mRNA. We found that codon optimization yielded a small increase in gag translational efficiency (approximately 1.6 fold). In contrast when cells were transfected with DNA vectors requiring nuclear transcription and processing of gag mRNA, codon optimization resulted in a very large enhancement of Gag production. We conclude that suboptimal codon usage by HIV-1 results in only a slight loss of gag translational efficiency per se, with the vast majority of enhancement in protein expression from DNA vectors due to altered processing and export of nuclear RNA.

  5. Characteristics influencing therapy switch behavior after suboptimal response to first-line treatment in patients with multiple sclerosis.

    Science.gov (United States)

    Teter, Barbara; Agashivala, Neetu; Kavak, Katelyn; Chouhfeh, Lynn; Hashmonay, Ron; Weinstock-Guttman, Bianca

    2014-06-01

    Factors driving disease-modifying therapy (DMT) switch behavior are not well understood. The objective of this paper is to identify patient characteristics and clinical events predictive of therapy switching in patients with suboptimal response to DMT. This retrospective study analyzed patients with relapsing-remitting multiple sclerosis (MS) and a suboptimal response to initial therapy with either interferon β or glatiramer acetate. Suboptimal responders were defined as patients with ≥1 MS event (clinical relapse, worsening disability, or MRI worsening) while on DMT. Switchers were defined as those who changed DMT within six to 12 months after the MS event. Of 606 suboptimal responders, 214 (35.3%) switched therapy. Switchers were younger at symptom onset (p = 0.012), MS diagnosis (p = 0.004), DMT initiation (p therapy switched sooner than patients who are older at the time of MS diagnosis and DMT initiation. © The Author(s) 2013.

  6. [Effects of chlorophyllin-iron on osmotic adjustment and activities of antioxidantive enzymes in cucumber seedlings under suboptimal temperature].

    Science.gov (United States)

    Zhang, Meng; Wang, Xiu-feng; Zhang, Fan-yang; Wei, Min; Shi, Qing-hua; Yang, Feng-juan; Li, Yan

    2014-12-01

    Cucumber cultivar 'Jinyan 4' was subjected to suboptimal temperature treatment of 18/12 degrees C (day/night) in the growth chambers. A solution culture experiment was conducted to study the effect of exogenously spraying 5 mg x L(-1) chlorophyllin-iron solution on plant growth, the content of proline, soluble sugar, MDA and activity of peroxidase in the leaves of cucumber seedling under suboptimal temperature. Application of chlorophyllin-iron showed prominent effects on mitigating the stress of suboptimal temperature on growth of the cucumber seedlings, significantly increasing the plant height, leaf area, shoot dry mass, the contents of soluble sugar and proline and the activities of SOD, POD, CAT and APX. Exogenously spraying chlorophyllin-iron could promote the accumulation of proline and soluble sugar, raise the activities of antioxidant enzymes, decrease the membrane lipid peroxidation and improve the adaptability of cucumber seedlings under suboptimal temperature.

  7. When the Learning Environment Is Suboptimal: Exploring Medical Students’ Perceptions of “Mistreatment”

    Science.gov (United States)

    Snell, Linda

    2014-01-01

    Purpose Despite widespread implementation of policies to address mistreatment, high rates of mistreatment during clinical training are reported, prompting the question of whether “mistreatment” means more to students than delineated in official codes of conduct. Understanding “mistreatment” from students’ perspective and as it relates to the learning environment is needed before effective interventions can be implemented. Method The authors conducted focus groups with final-year medical students at McGill University Faculty of Medicine in 2012. Participants were asked to characterize “suboptimal learning experience” and “mistreatment.” Transcripts were analyzed via inductive thematic analysis. Results Forty-one of 174 eligible students participated in six focus groups. Students described “mistreatment” as lack of respect or attack directed toward the person, and “suboptimal learning experience” as that which compromised their learning. Differing perceptions emerged as students debated whether “mistreatment” can be applied to negative learning environments as well as isolated incidents of mistreatment even though some experiences fell outside of the “official” label as per institutional policies. Whether students perceived “mistreatment” versus a “suboptimal learning experience” in negative environments appeared to be influenced by several key factors. A concept map integrating these ideas is presented. Conclusions How students perceived negative situations during training appears to be a complex process. When medical students say “mistreatment,” they may be referring to a spectrum, with incident-based mistreatment on one end and learning-environment-based mistreatment on the other. Multiple factors influenced how students perceived an environment-based negative situation and may provide strategies to improving the learning environment. PMID:24556767

  8. The importance of inhaler devices: the choice of inhaler device may lead to suboptimal adherence in COPD patients

    Directory of Open Access Journals (Sweden)

    Darbà J

    2015-10-01

    Full Text Available Josep Darbà,1 Gabriela Ramírez,2 Antoni Sicras,3 Pablo Francoli,4 Saku Torvinen,5 Rainel Sánchez-de la Rosa4 1Department of Economics, Universitat de Barcelona, 2BCN Health Economics and Outcomes Research SL, 3Dirección de Planificación, Badalona Serveis Assistencials, SA, Barcelona, 4Medical Department, TEVA Pharmaceutical, Madrid, Spain; 5Market Access Department, TEVA Pharmaceutical Europe BV, Amsterdam, the Netherlands Objective: This study aims to identify factors associated with poor adherence to COPD treatment in patients receiving a fixed-dose combination (FDC of inhaled corticosteroids and long-acting β2-agonist (ICS/LABA, focusing on the importance of inhaler devices.Methods: We conducted a retrospective and multicenter study based on a review of medical registries between 2007 and 2012 of COPD patients (n=1,263 treated with ICS/LABA FDC, whose medical devices were either dry powder inhalers (DPIs or pressurized metered-dose inhalers (pMDI. Medication adherence included persistence outcomes through 18 months and medication possession ratios. Data on exacerbations, comorbidities, demographic characteristics, and health care resource utilization were also included as confounders of adherence.Results: The analyses revealed that COPD patients whose medication was delivered through a DPI were less likely to have medication adherence compared to patients with pMDI, after adjusting for confounding factors, especially active ingredients. Younger groups of patients were less likely to be adherent compared to the oldest group. Smoker men were less likely to be adherent compared to women and non-smokers. Comorbidities decreased the probability of treatment adherence. Those patients that visited their doctor once a month were more likely to adhere to their medication regimen; however, suboptimal adherence was more likely to occur among those patients who visited more than three times per month their doctor. We also found that worsening of

  9. A Suboptimal Scheme for Multi-User Scheduling in Gaussian Broadcast Channels

    KAUST Repository

    Zafar, Ammar

    2014-05-28

    This work proposes a suboptimal multi-user scheduling scheme for Gaussian broadcast channels which improves upon the classical single user selection, while considerably reducing complexity as compared to the optimal superposition coding with successful interference cancellation. The proposed scheme combines the two users with the maximum weighted instantaneous rate using superposition coding. The instantaneous rate and power allocation are derived in closed-form, while the long term rate of each user is derived in integral form for all channel distributions. Numerical results are then provided to characterize the prospected gains of the proposed scheme.

  10. Audit-based education to reduce suboptimal management of cholesterol in primary care: a before and after study.

    Science.gov (United States)

    de Lusignan, S; Belsey, J; Hague, N; Dhoul, N; van Vlymen, J

    2006-12-01

    Statins are recommended for the secondary prevention of cardiovascular disease, although they are often used in suboptimal doses and some patients may not receive lipid-lowering therapy. The Primary Care Data Quality (PCDQ) programme is an audit-based educational intervention. To report the PCDQ programme's effect on the cholesterol management in cardiovascular disease. Subjects and methods Anonymized general practice data from 99 practices; 5% (n = 29 915) had cardiovascular diagnoses. Mean cholesterol fell from 4.75 to 4.64 mmol l(-1); patients achieving cholesterol target (< 5 mmol l(-1)) rose from 45.3 to 53.2%. Coronary heart disease patients achieved better control (mean 4.57 mmol l(-1)) than those with stroke (4.87 mmol l(-1)) or peripheral vascular disease (4.93 mmol l(-1)). Statin prescribing increased from 57.5 to 62.7%. Patients with diabetes [odds ratio (OR) 2.06, 95% confidence interval (95% CI) 1.91-2.21], prior myocardial infarction (MI) (OR 1.93, 95% CI 1.80-2.07), revascularization (OR 1.52, 95% CI 1.33-1.73) and smokers (OR 1.31, 95% CI 1.23-1.39) were more likely to receive statins, whereas people aged 75+ (OR 0.48, 95% CI 0.45-0.50), females (OR 0.90, 95% CI 0.86-0.94) and non-CHD-diagnosed (OR 0.36, 95% CI 0.34-0.38) were less likely. Diagnostic coding and number of patients who had their cholesterol measured and treated increased. There was no significant change in dosage used or inequity between the different groups prescribed statins.

  11. Suboptimal inhaler medication adherence and incorrect technique are common among chronic obstructive pulmonary disease patients.

    Science.gov (United States)

    Sriram, Krishna B; Percival, Matthew

    2016-02-01

    Patients with chronic obstructive pulmonary disease (COPD) are routinely prescribed one or more inhaled medications. Adherence to inhaler medications and correct inhaler device technique are crucial to successful COPD management. The goals of this study were to estimate adherence and inhaler technique in a cohort of COPD patients. This was an observational study conducted on a sample of 150 COPD patients. Medication adherence was assessed using the Medication Adherence Report Scale (MARS). Inhaler technique was assessed using standardized checklists. Clinical data were collected using a proforma. Of the 150 patients (mean age 70.3 years, 52% male), 58% reported suboptimal adherence (MARS ≤ 24). High adherence to therapy (MARS = 25) was associated with older age (p = 0.001), but not any of the other studied variables. Medication non-adherence was not associated with COPD exacerbations. Errors (≥ 1) in inhaler technique were common across all of the types of inhaler devices reportedly used by patients, with the highest proportion of errors among Turbuhaler users (83%) and the least proportion of errors among Handihaler users (50%). No clinical variables were associated with errors in inhaler technique. Suboptimal adherence and errors in inhaler technique are common among COPD patients. No clinical variables to assist in the prediction of medication non-adherence and poor inhaler technique were identifiable. Consequently, regular assessment of medication adherence and inhaler technique should be incorporated into routine clinical practice to facilitate improved health outcomes among patients with COPD. © The Author(s) 2015.

  12. Suboptimal Larval Habitats Modulate Oviposition of the Malaria Vector Mosquito Anopheles coluzzii.

    Directory of Open Access Journals (Sweden)

    Eunho Suh

    Full Text Available Selection of oviposition sites by gravid females is a critical behavioral step in the reproductive cycle of Anopheles coluzzii, which is one of the principal Afrotropical malaria vector mosquitoes. Several studies suggest this decision is mediated by semiochemicals associated with potential oviposition sites. To better understand the chemosensory basis of this behavior and identify compounds that can modulate oviposition, we examined the generally held hypothesis that suboptimal larval habitats give rise to semiochemicals that negatively influence the oviposition preference of gravid females. Dual-choice bioassays indicated that oviposition sites conditioned in this manner do indeed foster significant and concentration dependent aversive effects on the oviposition site selection of gravid females. Headspace analyses derived from aversive habitats consistently noted the presence of dimethyl disulfide (DMDS, dimethyl trisulfide (DMTS and 6-methyl-5-hepten-2-one (sulcatone each of which unitarily affected An. coluzzii oviposition preference. Electrophysiological assays across the antennae, maxillary palp, and labellum of gravid An. coluzzii revealed differential responses to these semiochemicals. Taken together, these findings validate the hypothesis in question and suggest that suboptimal environments for An. coluzzii larval development results in the release of DMDS, DMTS and sulcatone that impact the response valence of gravid females.

  13. An Approach to Streaming Video Segmentation With Sub-Optimal Low-Rank Decomposition.

    Science.gov (United States)

    Li, Chenglong; Lin, Liang; Zuo, Wangmeng; Wang, Wenzhong; Tang, Jin

    2016-05-01

    This paper investigates how to perform robust and efficient video segmentation while suppressing the effects of data noises and/or corruptions, and an effective approach is introduced to this end. First, a general algorithm, called sub-optimal low-rank decomposition (SOLD), is proposed to pursue the low-rank representation for video segmentation. Given the data matrix formed by supervoxel features of an observed video sequence, SOLD seeks a sub-optimal solution by making the matrix rank explicitly determined. In particular, the representation coefficient matrix with the fixed rank can be decomposed into two sub-matrices of low rank, and then we iteratively optimize them with closed-form solutions. Moreover, we incorporate a discriminative replication prior into SOLD based on the observation that small-size video patterns tend to recur frequently within the same object. Second, based on SOLD, we present an efficient inference algorithm to perform streaming video segmentation in both unsupervised and interactive scenarios. More specifically, the constrained normalized-cut algorithm is adopted by incorporating the low-rank representation with other low level cues and temporal consistent constraints for spatio-temporal segmentation. Extensive experiments on two public challenging data sets VSB100 and SegTrack suggest that our approach outperforms other video segmentation approaches in both accuracy and efficiency.

  14. Suboptimal and optimal order policies for fixed and varying replenishment interval with declining market

    Science.gov (United States)

    Yu, Jonas C. P.; Wee, H. M.; Yang, P. C.; Wu, Simon

    2016-06-01

    One of the supply chain risks for hi-tech products is the result of rapid technological innovation; it results in a significant decline in the selling price and demand after the initial launch period. Hi-tech products include computers and communication consumer's products. From a practical standpoint, a more realistic replenishment policy is needed to consider the impact of risks; especially when some portions of shortages are lost. In this paper, suboptimal and optimal order policies with partial backordering are developed for a buyer when the component cost, the selling price, and the demand rate decline at a continuous rate. Two mathematical models are derived and discussed: one model has the suboptimal solution with the fixed replenishment interval and a simpler computational process; the other one has the optimal solution with the varying replenishment interval and a more complicated computational process. The second model results in more profit. Numerical examples are provided to illustrate the two replenishment models. Sensitivity analysis is carried out to investigate the relationship between the parameters and the net profit.

  15. Sub-optimal parenting is associated with schizotypic and anxiety personality traits in adulthood.

    Science.gov (United States)

    Giakoumaki, S G; Roussos, P; Zouraraki, C; Spanoudakis, E; Mavrikaki, M; Tsapakis, E M; Bitsios, P

    2013-05-01

    Part of the variation in personality characteristics has been attributed to the child-parent interaction and sub-optimal parenting has been associated with psychiatric morbidity. In the present study, an extensive battery of personality scales (Trait Anxiety Inventory, Behavioural Inhibition/Activation System questionnaire, Eysenck Personality Questionnaire-Revised, Temperament and Character Inventory, Schizotypal Traits Questionnaire, Toronto Alexithymia Scale) and the Parental Bonding Instrument (PBI) were administered in 324 adult healthy males to elucidate the effects of parenting on personality configuration. Personality variables were analysed using Principal Component Analysis (PCA) and the factors "Schizotypy", "Anxiety", "Behavioural activation", "Novelty seeking" and "Reward dependence" were extracted. Associations between personality factors with PBI "care" and "overprotection" scores were examined with regression analyses. Subjects were divided into "parental style" groups and personality factors were subjected to categorical analyses. "Schizotypy" and "Anxiety" were significantly predicted by high maternal overprotection and low paternal care. In addition, the Affectionless control group (low care/high overprotection) had higher "Schizotypy" and "Anxiety" compared with the Optimal Parenting group (high care/low overprotection). These results further validate sub-optimal parenting as an important environmental exposure and extend our understanding on the mechanisms by which it increases risk for psychiatric morbidity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. Rescue Procedures after Suboptimal Deep Brain Stimulation Outcomes in Common Movement Disorders

    Directory of Open Access Journals (Sweden)

    Adam M. Nagy

    2016-10-01

    Full Text Available Deep brain stimulation (DBS is a unique, functional neurosurgical therapy indicated for medication refractory movement disorders as well as some psychiatric diseases. Multicontact electrodes are placed in “deep” structures within the brain with targets varying depending on the surgical indication. An implanted programmable pulse generator supplies the electrodes with a chronic, high frequency electrical current that clinically mimics the effects of ablative lesioning techniques. DBS’s efficacy has been well established for its movement disorder indications (Parkinson’s disease, essential tremor, and dystonia. However, clinical outcomes are sometimes suboptimal, even in the absence of common, potentially reversible complications such as hardware complications, infection, poor electrode placement, and poor programming parameters. This review highlights some of the rescue procedures that have been explored in suboptimal DBS cases for Parkinson’s disease, essential tremor, and dystonia. To date, the data is limited and difficult to generalize, but a large majority of published reports demonstrate positive results. The decision to proceed with such treatments should be made on a case by case basis. Larger studies are needed to clearly establish the benefit of rescue procedures and to establish for which patient populations they may be most appropriate.

  17. Design Of Real-Time Implementable Distributed Suboptimal Control: An LQR Perspective

    KAUST Repository

    Jaleel, Hassan

    2017-09-29

    We propose a framework for multiagent systems in which the agents compute their control actions in real time, based on local information only. The novelty of the proposed framework is that the process of computing a suboptimal control action is divided into two phases: an offline phase and an online phase. In the offline phase, an approximate problem is formulated with a cost function that is close to the optimal cost in some sense and is distributed, i.e., the costs of non-neighboring nodes are not coupled. This phase is centralized and is completed before the deployment of the system. In the online phase, the approximate problem is solved in real time by implementing any efficient distributed optimization algorithm. To quantify the performance loss, we derive upper bounds for the maximum error between the optimal performance and the performance under the proposed framework. Finally, the proposed framework is applied to an example setup in which a team of mobile nodes is assigned the task of establishing a communication link between two base stations with minimum energy consumption. We show through simulations that the performance under the proposed framework is close to the optimal performance and the suboptimal policy can be efficiently implemented online.

  18. Quality of reporting randomised controlled trials in major dental journals suboptimal.

    Science.gov (United States)

    Hurst, Dominic

    2011-01-01

    Hand searching of the most recent 24 issues of six high impact dental journals. RCTs involving only humans, from 24 issues of six leading specialty journals, covering a period up to July 2009 were included, including cluster randomised trials. Each article included in the study was assessed and scored independently by two observers, with any discrepancies being resolved by a third observer. In this study the modified CONSORT checklist was used to score each applicable item of data. The sum of the scores was converted to a percentage value for each trial. The data were analysed using descriptive statistics. Data regarding the publishing journal, country of origin of the trial, number of authors, involvement of statistician/epidemiologist, number of centres involved, ethics committee approval were subject to quantitative analysis. Ninety-five RCTs were identified with, according to the authors, generally suboptimal scores on quality reporting on key CONSORT areas. Significant differences in scores were found among the journals covering the named specialties. Overall there was a positive association between the quality score in studies with more authors, multicentre studies and studies in which a statistician/epidemiologist was involved. The overall quality of reporting RCTs in major dental journals was considered suboptimal in key CONSORT areas. This is very important as the reported results of RCTs can have an impact on future patient care.

  19. Development of Sub-optimal Airway Protocols for the International Space Station (ISS) by the Medical Operation Support Team (MOST)

    Science.gov (United States)

    Polk, James D.; Parazynski, Scott; Kelly, Scott; Hurst, Victor, IV; Doerr, Harold K.

    2007-01-01

    Airway management techniques are necessary to establish and maintain a patent airway while treating a patient undergoing respiratory distress. There are situations where such settings are suboptimal, thus causing the caregiver to adapt to these suboptimal conditions. Such occurrences are no exception aboard the International Space Station (ISS). As a result, the NASA flight surgeon (FS) and NASA astronaut cohorts must be ready to adapt their optimal airway management techniques for suboptimal situations. Based on previous work conducted by the Medical Operation Support Team (MOST) and other investigators, the MOST had members of both the FS and astronaut cohorts evaluate two oral airway insertion techniques for the Intubating Laryngeal Mask Airway (ILMA) to determine whether either technique is sufficient to perform in suboptimal conditions within a microgravity environment. Methods All experiments were conducted in a simulated microgravity environment provided by parabolic flight aboard DC-9 aircraft. Each participant acted as a caregiver and was directed to attempt both suboptimal ILMA insertion techniques following a preflight instruction session on the day of the flight and a demonstration of the technique by an anesthesiologist physician in the simulated microgravity environment aboard the aircraft. Results Fourteen participants conducted 46 trials of the suboptimal ILMA insertion techniques. Overall, 43 of 46 trials (94%) conducted were properly performed based on criteria developed by the MOST and other investigators. Discussion The study demonstrated the use of airway management techniques in suboptimal conditions relating to space flight. Use of these techniques will provide a crew with options for using the ILMA to manage airway issues aboard the ISS. Although it is understood that the optimal method for patient care during space flight is to have both patient and caregiver restrained, these techniques provide a needed backup should conditions not present

  20. Risk factors for suboptimal antiretroviral therapy adherence in HIV-infected adolescents in Gaborone, Botswana: a pilot cross-sectional study

    Directory of Open Access Journals (Sweden)

    Ndiaye M

    2013-09-01

    (HIV viral load <400 copies/mL. Multivariate logistic regression analysis was performed to identify independent predictors of ART non-adherence. Results: The overall median (interquartile range ART adherence was 99% (96.5–100 (N = 82. Seventy-six percent of adolescents had excellent pill count ART adherence levels and 94% achieved virologic suppression. Male adolescents made up 65% of the non-adherent group (P = 0.02. Those who displayed suboptimal ART adherence were more likely to report having ever missed ART doses due to failure to pick up medication at the pharmacy (30.0% versus 9.7%, P = 0.03. In the multivariate logistic regression model, male sex (odds ratio [OR] 3.29, 95% confidence interval [CI] 1.13–9.54; P = 0.03 was the only factor which was independently associated with suboptimal ART adherence. Conclusions: A high proportion of HIV-infected adolescents studied had excellent ART adherence and virologic suppression, with male adolescents at higher risk of suboptimal adherence than females. Further research to investigate how gender relates to suboptimal adherence may aid in the design of targeted intervention strategies. Keywords: HIV/AIDS, ART adherence, adolescents, barriers, Botswana

  1. Feature-preserving surface mesh smoothing via suboptimal Delaunay triangulation ☆

    Science.gov (United States)

    Gao, Zhanheng; Yu, Zeyun; Holst, Michael

    2012-01-01

    A method of triangular surface mesh smoothing is presented to improve angle quality by extending the original optimal Delaunay triangulation (ODT) to surface meshes. The mesh quality is improved by solving a quadratic optimization problem that minimizes the approximated interpolation error between a parabolic function and its piecewise linear interpolation defined on the mesh. A suboptimal problem is derived to guarantee a unique, analytic solution that is significantly faster with little loss in accuracy as compared to the optimal one. In addition to the quality-improving capability, the proposed method has been adapted to remove noise while faithfully preserving sharp features such as edges and corners of a mesh. Numerous experiments are included to demonstrate the performance of the method. PMID:23580890

  2. Suboptimal Rayleigh damping coefficients in seismic analysis of viscously-damped structures

    Science.gov (United States)

    Pan, Danguang; Chen, Genda; Wang, Zuocai

    2014-12-01

    An optimization method for the consistent evaluation of two Rayleigh damping coefficients is proposed. By minimizing an objective function such as an error term of the peak displacement of a structure, the two coefficients can be determined with response spectral analysis. The optimization method degenerates into the conventional method used in current practices when only two modes of vibration are included in the objective function. Therefore, the proposed method with all significant modes included for simplicity in practical applications results in suboptimal damping coefficients. The effects of both spatial distribution and frequency content of excitations as well as structural dynamic characteristics on the evaluation of Rayleigh damping coefficients were investigated with a five-story building structure. Two application examples with a 62-story high-rise building and a 840 m long cable-stayed bridge under ten earthquake excitations demonstrated the accuracy and effectiveness of the proposed method to account for all of the above effects.

  3. A similar correction mechanism in slow and fluent readers after suboptimal landing positions.

    Directory of Open Access Journals (Sweden)

    Benjamin eGagl

    2014-06-01

    Full Text Available The present eye movements study investigated the optimal viewing position (OVP and inverted-optimal viewing position (I-OVP effects in slow readers. The basis of these effects is a phenomenon called corrective re-fixations, which describes a short saccade from a suboptimal landing position (word beginning or end to the center of the word. The present study found corrective re-fixations in slow readers, which was evident from the I-OVP effects in first fixation durations, the OVP effect in number of fixations and the OVP effect in re-fixation probability. The main result is that slow readers, despite being characterized by a fragmented eye movement pattern during reading, nevertheless share an intact mechanism for performing corrective re-fixations. This correction mechanism is not linked to linguistic processing, but to visual and oculomotor processes, which suggests the integrity of oculomotor and visual processes in slow readers.

  4. Sub-optimal asthma control in teenagers in the midland region of Ireland.

    Science.gov (United States)

    Kelly, I; Fitzpatrick, P

    2011-12-01

    Internationally, many children with asthma are not attaining achievable asthma control. To examine the prevalence of asthma in teenagers in four midland counties, their asthma control and the barriers, if any, to gaining control of asthma. International Study of Asthma and Allergies in Children (ISAAC) methodology was used in a survey of Junior Cycle Year 2 second-level students. The prevalence of "wheeze ever" was 49.8%, "wheeze in the last 12 months" was 32.6% and "asthma ever" was 23.5%. Of teenagers with current asthma, 96% had evidence of sub-optimal asthma control during the previous year. For the majority of the teenagers with asthma, treatment was not guideline concordant; infrequent lung function testing, insufficient review after acute care and poor use of written asthma action plans. Barriers included lack of awareness of need for treatment. If asthma guidelines are implemented fully, these children may experience better health.

  5. Improvement of Suboptimal Land Productivity Approach by Land and Plant Management

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    Marthen Pasang Sirappa

    2014-06-01

    Full Text Available Assessment for increasing productivity of suboptimal land with using three kinds of organic fertilizer and six rice varieties had been conducted in the Debowae village, Waeapo district, Buru regency at 2011. Purpose of the assessment were to determine the effect of three types organic fertilizer and the use of six Inpara varieties to growth and productivity of rice in sub-optimal land. Study used a split plot design with three replications (farmers as replicates, where the main plot was three types of organic fertilizers (livestock manure, granular organic, and petroganic, while the subplot was 6 varieties Inpara (Inpara 1, Inpara 2, Inpara 3, Inpara 4, Inpara 5, and Indragiri. The soil types at the study site based on soil classification were Endoaquepts with soil fertility status was low. The study results showed that the use of organic manure combined with inorganic fertilizers, both from livestock manure, while granular organic and petrogranic, gave an average crop growth and yield better than the results obtained by farmers outside of the study. Average petroganic fertilizer had a better growth and higher crop yields compared to other organic fertilizers. The six varieties of rice swamps that were examined (Inpara 1, Inpara 2, Inpara 3, Inpara 4, Inpara 5, and Indragiri had the average growth and better yields than rice varieties used by farmers outside of the study (2.75 Mg ha-1. Varieties Inpara 4, Indragiri, Inpara 1 and Inpara 2 had average yield above 7 Mg ha-1, while Inpara 3 and Inpara 5 average above 4 Mg ha-1. Combination of granular organic fertilizer with Inpara 4 variety and petroganic with Indragiri variety had the best results (8.37 and 8.02 Mg ha-1, while the lowest yield (4.48 Mg ha-1 was reached at combination of livestock manure with Inpara 5 variety.

  6. A PROCEDURE FOR DETERMINING OPTIMAL FACILITY LOCATION AND SUB-OPTIMAL POSITIONS

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    P.K. Dan

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: This research presents a methodology for determining the optimal location of a new facility, having physical flow interaction of various degrees with other existing facilities in the presence of barriers impeding the shortest flow-path as well as the sub-optimal iso-cost positions. It also determines sub-optimal iso-cost positions with additional cost or penalty for not being able to site it at the computed optimal point. The proposed methodology considers all types of quadrilateral barrier or forbidden region configurations to generalize and by-pass such impenetrable obstacles, and adopts a scheme of searching through the vertices of the quadrilaterals to determine the alternative shortest flow-path. This procedure of obstacle avoidance is novel. Software has been developed to facilitate computations for the search algorithm to determine the optimal and iso-cost co-ordinates. The test results are presented.

    AFRIKAANSE OPSOMMING: Die navorsing behandel ‘n procedure vir die bepaling van optimum stigtingsposisie vir ‘n onderneming met vloei vanaf ander bestaande fasiliteite in die teenwoordigheid van ‘n verskeidenheid van randvoorwaardes. Die prodedure lewer as resultaat suboptimale isokoste-stigtingsplekke met bekendmaking van die koste wat onstaan a.g.v. afwyking van die randvoorwaardlose optimum oplossingskoste, die prosedure maak gebruik van ‘n vindingryke soekmetode wat toegepas word op niersydige meerkundige voorstellings vir die bepaling van korste roetes wat versperring omseil. Die prosedure word onderskei deur programmatuur. Toetsresultate word voorgehou.

  7. COMPARISON OF MAIZE INBRED LINES DIFFERING IN LOW-TEMPERATURE TOLERANCE - EFFECT OF ACCLIMATION AT SUBOPTIMAL TEMPERATURE ON CHLOROPLAST FUNCTIONING

    NARCIS (Netherlands)

    VERHEUL, MJ; VANHASSEL, PR; STAMP, P

    Acclimation to optimal or suboptimal temperature may influence photosynthetic properties of different maize genotypes in distinct ways. In this study, leaf growth and chloroplast functioning of the second leaves of Penjalinan, an inbred line used in warm tropical regions (CS) and Z7, an inbred line

  8. Physician, organizational, and patient factors associated with suboptimal blood pressure management in type 2 diabetic patients in primary care

    NARCIS (Netherlands)

    Schaars, Carel F; Denig, Petra; Kasje, Willeke N; Stewart, Roy E; Wolffenbuttel, Bruce H R; Haaijer-Ruskamp, Flora M

    OBJECTIVE: To assess the quality of hypertension care in patients with type 2 diabetes in general practice and identify physician, organizational, and patient factors associated with suboptimal care. RESEARCH DESIGN AND METHODS: Data from 895 randomly selected diabetic patients were extracted from

  9. TECHNOLOGICAL INNOVATION AND BUSINESS DIVERSIFICATION: SUSTAINABILITY LIVELIHOODS IMPROVEMENT SCENARIO OF RICE FARMER HOUSEHOLD IN SUB-OPTIMAL LAND

    Directory of Open Access Journals (Sweden)

    Adriani D.

    2017-09-01

    Full Text Available The increased role of the sub-optimal land to support food security continue to be encouraged in Indonesia, given the more limited expansion for potential land. But until recently, development of sub-optimal land becomes not an easy thing. Ecological and technical barriers became the main issue. A series of these issues resulted in a high number of underemproleymeny and poverty in agriculture region. Technological inovation of agriculture and the business diversification can be seen be the solution to those issues. This research aims to analyze the impact of the technological innovation and business diversification on underemployment, working time, household income and also sustainable livelihoods of farmers on the sub-optimal land. The research was carried out in Pemulutan District, Ogan Ilir Regency, South Sumatra Province, Indonesia. The objects of research are farmers which adopter and non adopter technological innovation, and also work outside of paddy farming (business diversification. The research method is the survey. Method of sampling is stratified random sampling. Data obtained in the field analyses using descriptive statistics and inferesia. The results showed there are positive impact of technological innovation on the allocation of working time farmer households, the numbers underemployment, household income and livelihood sustainability. Determinant factors for farmers in applying technology and business diversification are paddy farming income, off-farm income, and age. The use of technology and business diversification proves to be one of the positive scenarios for sustainable livelihood of farmers in sub-optimal land.

  10. Two Liters a Day Keep the Doctor Away? Considerations on the Pathophysiology of Suboptimal Fluid Intake in the Common Population

    OpenAIRE

    Florian Lang; Isabelle Guelinckx; Guillaume Lemetais; Olle Melander

    2017-01-01

    Suboptimal fluid intake may require enhanced release of antidiuretic hormone (ADH) or vasopressin for the maintenance of adequate hydration. Enhanced copeptin levels (reflecting enhanced vasopressin levels) in 25% of the common population are associated with enhanced risk of metabolic syndrome with abdominal obesity, type 2 diabetes, hypertension, coronary artery disease, heart failure, vascular dementia, cognitive impairment, microalbuminuria, chronic kidney disease, inflammatory bowel disea...

  11. Dose Titration Algorithm Tuning (DTAT) should supersede 'the' Maximum Tolerated Dose (MTD) in oncology dose-finding trials.

    Science.gov (United States)

    Norris, David C

    2017-01-01

    Background. Absent adaptive, individualized dose-finding in early-phase oncology trials, subsequent 'confirmatory' Phase III trials risk suboptimal dosing, with resulting loss of statistical power and reduced probability of technical success for the investigational therapy. While progress has been made toward explicitly adaptive dose-finding and quantitative modeling of dose-response relationships, most such work continues to be organized around a concept of 'the' maximum tolerated dose (MTD). The purpose of this paper is to demonstrate concretely how the aim of early-phase trials might be conceived, not as 'dose-finding', but as dose titration algorithm (DTA)-finding. Methods. A Phase I dosing study is simulated, for a notional cytotoxic chemotherapy drug, with neutropenia constituting the critical dose-limiting toxicity. The drug's population pharmacokinetics and myelosuppression dynamics are simulated using published parameter estimates for docetaxel. The amenability of this model to linearization is explored empirically. The properties of a simple DTA targeting neutrophil nadir of 500 cells/mm 3 using a Newton-Raphson heuristic are explored through simulation in 25 simulated study subjects. Results. Individual-level myelosuppression dynamics in the simulation model approximately linearize under simple transformations of neutrophil concentration and drug dose. The simulated dose titration exhibits largely satisfactory convergence, with great variance in individualized optimal dosing. Some titration courses exhibit overshooting. Conclusions. The large inter-individual variability in simulated optimal dosing underscores the need to replace 'the' MTD with an individualized concept of MTD i . To illustrate this principle, the simplest possible DTA capable of realizing such a concept is demonstrated. Qualitative phenomena observed in this demonstration support discussion of the notion of tuning such algorithms. Although here illustrated specifically in relation to

  12. Dose Titration Algorithm Tuning (DTAT) should supersede ‘the’ Maximum Tolerated Dose (MTD) in oncology dose-finding trials

    Science.gov (United States)

    Norris, David C.

    2017-01-01

    Background. Absent adaptive, individualized dose-finding in early-phase oncology trials, subsequent ‘confirmatory’ Phase III trials risk suboptimal dosing, with resulting loss of statistical power and reduced probability of technical success for the investigational therapy. While progress has been made toward explicitly adaptive dose-finding and quantitative modeling of dose-response relationships, most such work continues to be organized around a concept of ‘the’ maximum tolerated dose (MTD). The purpose of this paper is to demonstrate concretely how the aim of early-phase trials might be conceived, not as ‘dose-finding’, but as dose titration algorithm (DTA)-finding. Methods. A Phase I dosing study is simulated, for a notional cytotoxic chemotherapy drug, with neutropenia constituting the critical dose-limiting toxicity. The drug’s population pharmacokinetics and myelosuppression dynamics are simulated using published parameter estimates for docetaxel. The amenability of this model to linearization is explored empirically. The properties of a simple DTA targeting neutrophil nadir of 500 cells/mm 3 using a Newton-Raphson heuristic are explored through simulation in 25 simulated study subjects. Results. Individual-level myelosuppression dynamics in the simulation model approximately linearize under simple transformations of neutrophil concentration and drug dose. The simulated dose titration exhibits largely satisfactory convergence, with great variance in individualized optimal dosing. Some titration courses exhibit overshooting. Conclusions. The large inter-individual variability in simulated optimal dosing underscores the need to replace ‘the’ MTD with an individualized concept of MTD i . To illustrate this principle, the simplest possible DTA capable of realizing such a concept is demonstrated. Qualitative phenomena observed in this demonstration support discussion of the notion of tuning such algorithms. Although here illustrated specifically

  13. Extension of suboptimal control theory for flow around a square cylinder

    Science.gov (United States)

    Fujita, Yosuke; Fukagata, Koji

    2017-11-01

    We extend the suboptimal control theory to control of flow around a square cylinder, which has no point symmetry on the impulse response from the wall in contrast to circular cylinders and spheres previously studied. The cost functions examined are the pressure drag (J1), the friction drag (J2), the squared difference between target pressure and wall pressure (J3) and the time-averaged dissipation (J4). The control input is assumed to be continuous blowing and suction on the cylinder wall and the feedback sensors are assumued on the entire wall surface. The control law is derived so as to minimize the cost function under the constraint of linearized Navier-Stokes equation, and the impulse response field to be convolved with the instantaneous flow quanties are numerically obtained. The amplitide of control input is fixed so that the maximum blowing/suction velocity is 40% of the freestream velocity. When J2 is used as the cost function, the friction drag is reduced as expected but the mean drag is found to increase. In constast, when J1, J3, and J4 were used, the mean drag was found to decrease by 21%, 12%, and 22%, respectively; in addition, vortex shedding is suppressed, which leads to reduction of lift fluctuations.

  14. Suboptimal HIV Testing Uptake Among Men Who Engage in Commercial Sex Work with Men in Asia.

    Science.gov (United States)

    Jin, Harry; Friedman, Mackey Reuel; Lim, Sin How; Guadamuz, Thomas E; Wei, Chongyi

    2016-12-01

    Men who have sex with men and are sex workers (MSMSW) are disproportionately affected by the growing and emerging HIV epidemic. As sex work and same-sex behavior are heavily stigmatized and often illegal in most Asian countries, HIV research focusing on MSMSW has been limited. The goal of this analysis is to examine HIV testing practices and identify correlates of HIV testing among MSMSW in Asia. The Asia Internet MSM Sex Survey, an online cross-sectional survey of 10,861 men who have sex with men (MSM), was conducted in 2010. Data on sociodemographic characteristics, HIV testing behaviors, and sexual behaviors were collected. Five hundred and seventy-four HIV-negative/unknown respondents reported receiving payment for sex with men at least once in the past 6 months and were included in this analysis. Multivariable logistic regression was conducted to identify independent correlates of HIV testing in the past year. About half (48.6%) of the participants had been tested for HIV at least once within the past year, and 30.5% had never been tested. We also found that MSMSW participants who engaged in risky behaviors were less likely to be tested. While one might expect a high HIV testing rate among MSMSW due to the risks associated with engaging in sex work, we found that HIV testing uptake is suboptimal among MSMSW in Asia. These results suggest that targeted HIV prevention and testing promotion among MSMSW are needed.

  15. Suboptimal Nutritional Characteristics in Male and Female Soldiers Compared to Sports Nutrition Guidelines.

    Science.gov (United States)

    Beals, Kim; Darnell, Matthew E; Lovalekar, Mita; Baker, Rachel A; Nagai, Takashi; San-Adams, Thida; Wirt, Michael D

    2015-12-01

    The purpose of this study was to evaluate the nutrient intake of male and female Soldiers in the 101 st Airborne Division (Air Assault) compared to sports nutrition standards for athletes, and to identify suboptimal eating characteristics that may impair physical performance and jeopardize military readiness. Male and female Soldiers from the 101 st Airborne Division (Air Assault) completed a 24-hour dietary recall and nutrition history questionnaire before anthropometric and body composition measurements were taken. Compared to sports nutrition guidelines, Soldiers of the 101 st under consume carbohydrates (males: 3.9 ± 2.0 vs. 5.0 g/kg, p < 0.001; females: 4.0 ± 2.1 vs. 5.0 g/kg, p = 0.001), male Soldiers eat too much fat (32.4% of kcal vs. <30% of kcal, p = 0.000) and saturated fat (males: 10.5 ± 3.9% of kcal vs. 10.0% of kcal, p = 0.044), and both males and females follow a meal pattern that may not optimize energy availability throughout the day. Eating too much fat and under fueling carbohydrate may negatively impact the adaptations to physical training and compromise overall health. Although Soldiers continue to participate in arduous training programs, future research should be aimed at determining the energy and macronutrient needs to fuel and recover from specific types of military training. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  16. Suboptimal evolutionary novel environments promote singular altered gravity responses of transcriptome during Drosophila metamorphosis.

    Science.gov (United States)

    Herranz, Raul; Larkin, Oliver J; Hill, Richard J A; Lopez-Vidriero, Irene; van Loon, Jack J W A; Medina, F Javier

    2013-06-27

    Previous experiments have shown that the reduced gravity aboard the International Space Station (ISS) causes important alterations in Drosophila gene expression. These changes were shown to be intimately linked to environmental space-flight related constraints. Here, we use an array of different techniques for ground-based simulation of microgravity effects to assess the effect of suboptimal environmental conditions on the gene expression of Drosophila in reduced gravity. A global and integrative analysis, using "gene expression dynamics inspector" (GEDI) self-organizing maps, reveals different degrees in the responses of the transcriptome when using different environmental conditions or microgravity/hypergravity simulation devices. Although the genes that are affected are different in each simulation technique, we find that the same gene ontology groups, including at least one large multigene family related with behavior, stress response or organogenesis, are over represented in each case. These results suggest that the transcriptome as a whole can be finely tuned to gravity force. In optimum environmental conditions, the alteration of gravity has only mild effects on gene expression but when environmental conditions are far from optimal, the gene expression must be tuned greatly and effects become more robust, probably linked to the lack of experience of organisms exposed to evolutionary novel environments such as a gravitational free one.

  17. Daily menus can result in suboptimal nutrient intakes, especially calcium, of adolescents living in dormitories.

    Science.gov (United States)

    Kresić, Greta; Simundić, Borislav; Mandić, Milena L; Kendel, Gordana; Zezelj, Sandra Pavicić

    2008-03-01

    The aims of this study were to evaluate daily menus in Croatian dormitories and to assess the overall intake of dairy products among resident adolescents. For this purpose, 168 daily menus were chosen for nutritional evaluation by random sampling. In addition, 227 adolescents (133 girls and 94 boys) participated in a questionnaire focused on food intake in addition to the meals supplied in dormitories with the aim to assess the amount and the type of dairy products consumed. The results showed that only 35% of the daily menus were nutritionally balanced. Most of the menus provided an excess of energy, protein, carbohydrate, saturated fat, phosphorus, riboflavin, and vitamin A. The levels of calcium and magnesium in the menus were suboptimal. The menus offered to adolescents provided approximately 2 servings of dairy products per day. Milk was the most often supplied dairy product (1.1 servings per day), whereas yogurt had the lowest frequency of serving (0.2 servings per day). The most preferred dairy-based snack for both sexes was milk. Dairy-based snacks provided about 1 serving per day for both sexes and contributed to about 30% of the recommended dietary allowances for calcium. Adolescents who regularly consumed dairy-based snacks meet the recommendations (3.2 servings of dairy products per day and about 98% recommended dietary allowances for calcium). We conclude that the institutional menu planning should be improved because the intake of dairy snacks will continue to be a problem for achieving a healthy diet in adolescences.

  18. Parasitological and transcriptomic comparison of Strongyloides ratti infections in natural and in suboptimal permissive hosts.

    Science.gov (United States)

    Jaleta, Tegegn G; Rödelsperger, Christian; Streit, Adrian

    2017-09-01

    The nematode genus Strongyloides consists of fairly species-specific small intestinal parasites of various vertebrates, among them the human pathogen S. stercoralis. Between the parthenogenetic parasitic generations these worms can also form single facultative sexual free-living generations. In addition to their primary hosts, several species can also live more or less well in other permissive hosts, which are sometimes not very closely related with the normal host. For example, S. stercoralis can also infect dogs and non-human primates. Here we compare the infection and reproductive success over time and the gene expression profiles as determined by quantitative sequencing of S. ratti parasitizing in its natural host rat and in the permissive host gerbil. We show that in gerbils fewer infective larvae successfully establish in the host, but those that do accomplish this survive and reproduce for longer and produced a higher proportion of males during the first two month of infection. Globally, the gene expression profiles in the two hosts are very similar. Among the relatively few differentially expressed genes, astacin-like and acetylcholinesterase genes are prominently represented. In the future it will be interesting to see if these changes in the suboptimal host are indeed ecologically sensible responses to the different host. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Development and evaluation of a questionnaire for measuring suboptimal health status in urban Chinese.

    Science.gov (United States)

    Yan, Yu-Xiang; Liu, You-Qin; Li, Man; Hu, Pei-Feng; Guo, Ai-Min; Yang, Xing-Hua; Qiu, Jing-Jun; Yang, Shan-Shan; Shen, Jian; Zhang, Li-Ping; Wang, Wei

    2009-01-01

    Suboptimal health status (SHS) is characterized by ambiguous health complaints, general weakness, and lack of vitality, and has become a new public health challenge in China. It is believed to be a subclinical, reversible stage of chronic disease. Studies of intervention and prognosis for SHS are expected to become increasingly important. Consequently, a reliable and valid instrument to assess SHS is essential. We developed and evaluated a questionnaire for measuring SHS in urban Chinese. Focus group discussions and a literature review provided the basis for the development of the questionnaire. Questionnaire validity and reliability were evaluated in a small pilot study and in a larger cross-sectional study of 3000 individuals. Analyses included tests for reliability and internal consistency, exploratory and confirmatory factor analysis, and tests for discriminative ability and convergent validity. The final questionnaire included 25 items on SHS (SHSQ-25), and encompassed 5 subscales: fatigue, the cardiovascular system, the digestive tract, the immune system, and mental status. Overall, 2799 of 3000 participants completed the questionnaire (93.3%). Test-retest reliability coefficients of individual items ranged from 0.89 to 0.98. Item-subscale correlations ranged from 0.51 to 0.72, and Cronbach's alpha was 0.70 or higher for all subscales. Factor analysis established 5 distinct domains, as conceptualized in our model. One-way ANOVA showed statistically significant differences in scale scores between 3 occupation groups; these included total scores and subscores (Purban Chinese.

  20. Motor planning under temporal uncertainty is suboptimal when the gain function is asymmetric.

    Science.gov (United States)

    Ota, Keiji; Shinya, Masahiro; Kudo, Kazutoshi

    2015-01-01

    For optimal action planning, the gain/loss associated with actions and the variability in motor output should both be considered. A number of studies make conflicting claims about the optimality of human action planning but cannot be reconciled due to their use of different movements and gain/loss functions. The disagreement is possibly because of differences in the experimental design and differences in the energetic cost of participant motor effort. We used a coincident timing task, which requires decision making with constant energetic cost, to test the optimality of participant's timing strategies under four configurations of the gain function. We compared participant strategies to an optimal timing strategy calculated from a Bayesian model that maximizes the expected gain. We found suboptimal timing strategies under two configurations of the gain function characterized by asymmetry, in which higher gain is associated with higher risk of zero gain. Participants showed a risk-seeking strategy by responding closer than optimal to the time of onset/offset of zero gain. Meanwhile, there was good agreement of the model with actual performance under two configurations of the gain function characterized by symmetry. Our findings show that human ability to make decisions that must reflect uncertainty in one's own motor output has limits that depend on the configuration of the gain function.

  1. Altered Innate Immune Responses in Neutrophils from Patients with Well- and Suboptimally Controlled Asthma

    Directory of Open Access Journals (Sweden)

    Francesca S. M. Tang

    2015-01-01

    Full Text Available Background. Respiratory infections are a major cause of asthma exacerbations where neutrophilic inflammation dominates and is associated with steroid refractory asthma. Structural airway cells in asthma differ from nonasthmatics; however it is unknown if neutrophils differ. We investigated neutrophil immune responses in patients who have good (AGood and suboptimal (ASubopt asthma symptom control. Methods. Peripheral blood neutrophils from AGood (ACQ 0.75, n=7, and healthy controls (HC (n=9 were stimulated with bacterial (LPS (1 μg/mL, fMLF (100 nM, and viral (imiquimod (3 μg/mL, R848 (1.5 μg/mL, and poly I:C (10 μg/mL surrogates or live rhinovirus (RV 16 (MOI1. Cell-free supernatant was collected after 1 h for neutrophil elastase (NE and matrix metalloproteinase- (MMP- 9 measurements or after 24 h for CXCL8 release. Results. Constitutive NE was enhanced in AGood neutrophils compared to HC. fMLF stimulated neutrophils from ASubopt but not AGood produced 50% of HC levels. fMLF induced MMP-9 was impaired in ASubopt and AGood compared to HC. fMLF stimulated CXCL8 but not MMP-9 was positively correlated with FEV1 and FEV1/FVC. ASubopt and AGood responded similarly to other stimuli. Conclusions. Circulating neutrophils are different in asthma; however, this is likely to be related to airflow limitation rather than asthma control.

  2. Sub-optimal wavelet denoising of coaveraged spectra employing statistics from individual scans.

    Science.gov (United States)

    Galvão, Roberto Kawakami Harrop; Filho, Heronides Adonias Dantas; Martins, Marcelo Nascimento; Araújo, Mário César Ugulino; Pasquini, Celio

    2007-01-02

    This paper proposes a novel wavelet denoising method, which exploits the statistics of individual scans acquired in the course of a coaveraging process. The proposed method consists of shrinking the wavelet coefficients of the noisy signal by a factor that minimizes the expected square error with respect to the true signal. Since the true signal is not known, a sub-optimal estimate of the shrinking factor is calculated by using the sample statistics of the acquired scans. It is shown that such an estimate can be generated as the limit value of a recursive formulation. In a simulated example, the performance of the proposed method is seen to be equivalent to the best choice between hard and soft thresholding for different signal-to-noise ratios. Such a conclusion is also supported by an experimental investigation involving near-infrared (NIR) scans of a diesel sample. It is worth emphasizing that this experimental example concerns the removal of actual instrumental noise, in contrast to other case studies in the denoising literature, which usually present simulations with artificial noise. The simulated and experimental cases indicate that, in classic denoising based on wavelet coefficient thresholding, choosing between the hard and soft options is not straightforward and may lead to considerably different outcomes. By resorting to the proposed method, the analyst is not required to make such a critical decision in order to achieve appropriate results.

  3. Metabonomics-Based Study of Clinical Urine Samples in Suboptimal Health with Different Syndromes

    Directory of Open Access Journals (Sweden)

    Hai-Zhen Cui

    2013-01-01

    Full Text Available Objective. To explore the urinary biochemistry features of syndromes of traditional Chinese medicine (TCM such as syndrome of stagnation of liver Qi, spleen deficiency, liver Qi stagnation, and spleen deficiency (LSSDS in sub-optimal health status (SHS. Methods. 12 cases for each syndrome group in SHS were selected, 12 subjects were used as a normal control group, and 1H NMR detection was, respectively, carried out, and the data was corrected by the orthogonal signal correction (OSC and then adopted a partial least squares (PLS method for discriminate analysis. Results. The OSC-PLS (ctr analysis results of the nuclear overhauser enhancement spectroscopy (NOESY detection indicated that the syndromes in SHS could be differentiated, and there were significant differences in the levels of metabolites of the urine samples of the four groups; the biomarkers of LSSDS in SHS were found out. The contents of citric acid (2.54 and 2.66, trimethylamineoxide (3.26, and hippuric acid (3.98, 7.54, 7.58, 7.62, 7.66, 7.82, and 7.86 in the urine samples of LSSDS group were lower than that of the normal control group. Conclusion. There are differences in the 1H-NMR metabolic spectrum of the urine samples of the four groups, and the specific metabolic products of the LSSDS in SHS can be identified from metabonomics analysis.

  4. Suboptimal provision of preventive healthcare due to expected enrollee turnover among private insurers.

    Science.gov (United States)

    Herring, Bradley

    2010-04-01

    Many preventive healthcare procedures are widely recognized as cost-effective but have relatively low utilization rates in the US. Because preventive care is a present-period investment with a future-period expected financial return, enrollee turnover among private insurers lowers the expected return of this investment. In this paper, I present a simple theoretical model to illustrate the suboptimal provision of preventive healthcare that results from insurers 'free riding' off of the provision from others. I also provide an empirical test of this hypothesis using data from the Community Tracking Study's Household Survey. I use lagged market-level measures of employment-induced insurer turnover to identify variation in insurers' expectations and test for the effect of turnover on several different measures of medical utilization. As expected, I find that turnover has a significantly negative effect on the utilization of preventive services and has no effect on the utilization of acute services used as a control. Copyright (c) 2009 John Wiley & Sons, Ltd.

  5. Economic and disease burden of breast cancer associated with suboptimal breastfeeding practices in Mexico.

    Science.gov (United States)

    Unar-Munguía, Mishel; Meza, Rafael; Colchero, M Arantxa; Torres-Mejía, Gabriela; de Cosío, Teresita Gonzalez

    2017-10-05

    Exclusive breastfeeding and longer breastfeeding reduce women's breast cancer risk but Mexico has one of the lowest breastfeeding rates worldwide. We estimated the lifetime economic and disease burden of breast cancer in Mexico if 95% of parous women breastfeed each child exclusively for 6 months and continue breastfeeding for over a year. We used a static microsimulation model with a cost-of-illness approach to simulate a cohort of Mexican women. We estimated breast cancer incidence, premature mortality, disability-adjusted life years (DALYs), medical costs, and income losses due to breast cancer and extrapolated the results to 1.116 million Mexican women of age 15 in 2012. Costs were expressed in 2015 US dollars and discounted at a 3% annual rate. We estimated that 2,186 premature deaths (95% CI 2,123-2,248), 9,936 breast cancer cases (95% CI 9,651-10,220), 45,109 DALYs (95% CI 43,000-47,217), and $245 million USD (95% CI 234-256) in medical costs and income losses owing to breast cancer could be saved over a cohort's lifetime. Medical costs account for 80% of the economic burden; income losses and opportunity costs for caregivers account for 15 and 5%, respectively. In Mexico, the burden of breast cancer due to suboptimal breastfeeding in women is high in terms of morbidity, premature mortality, and the economic costs for the health sector and society.

  6. Effects of Suboptimally Presented Erotic Pictures on Moral Judgments: A Cross-Cultural Comparison

    Science.gov (United States)

    Martí-Vilar, Manuel; Arango, Olber Eduardo

    2016-01-01

    Previous research has identified a set of core factors that influence moral judgments. The present study addresses the interplay between moral judgments and four factors: (a) incidental affects, (b) sociocultural context, (c) type of dilemma, and (d) participant’s sex. We asked participants in two different countries (Colombia and Spain) to judge the acceptability of actions in response to personal and impersonal moral dilemmas. Before each dilemma an affective prime (erotic, pleasant or neutral pictures) was presented suboptimally. Our results show that: a) relative to neutral priming, erotic primes increase the acceptance of harm for a greater good (i.e., more utilitarian judgments), b) relative to Colombians, Spanish participants rated causing harm as less acceptable, c) relative to impersonal dilemmas, personal dilemmas reduced the acceptance of harm, and d) relative to men, women were less likely to consider harm acceptable. Our results are congruent with findings showing that sex is a crucial factor in moral cognition, and they extend previous research by showing the interaction between culture and incidental factors in the making of moral judgments. PMID:27367795

  7. Effects of Suboptimally Presented Erotic Pictures on Moral Judgments: A Cross-Cultural Comparison.

    Directory of Open Access Journals (Sweden)

    Antonio Olivera-La Rosa

    Full Text Available Previous research has identified a set of core factors that influence moral judgments. The present study addresses the interplay between moral judgments and four factors: (a incidental affects, (b sociocultural context, (c type of dilemma, and (d participant's sex. We asked participants in two different countries (Colombia and Spain to judge the acceptability of actions in response to personal and impersonal moral dilemmas. Before each dilemma an affective prime (erotic, pleasant or neutral pictures was presented suboptimally. Our results show that: a relative to neutral priming, erotic primes increase the acceptance of harm for a greater good (i.e., more utilitarian judgments, b relative to Colombians, Spanish participants rated causing harm as less acceptable, c relative to impersonal dilemmas, personal dilemmas reduced the acceptance of harm, and d relative to men, women were less likely to consider harm acceptable. Our results are congruent with findings showing that sex is a crucial factor in moral cognition, and they extend previous research by showing the interaction between culture and incidental factors in the making of moral judgments.

  8. Motor planning under temporal uncertainty is suboptimal when the gain function is asymmetric

    Directory of Open Access Journals (Sweden)

    Keiji eOta

    2015-07-01

    Full Text Available For optimal action planning, the gain/loss associated with actions and the variability in motor output should both be considered. A number of studies make conflicting claims about the optimality of human action planning but cannot be reconciled due to their use of different movements and gain/loss functions. The disagreement is possibly because of differences in the experimental design and differences in the energetic cost of participant motor effort. We used a coincident timing task, which requires decision making with constant energetic cost, to test the optimality of participant’s timing strategies under four configurations of the gain function. We compared participant strategies to an optimal timing strategy calculated from a Bayesian model that maximizes the expected gain. We found suboptimal timing strategies under two configurations of the gain function characterized by asymmetry, in which higher gain is associated with higher risk of zero gain. Participants showed a risk-seeking strategy by responding closer than optimal to the time of onset/offset of zero gain. Meanwhile, there was good agreement of the model with actual performance under two configurations of the gain function characterized by symmetry. Our findings show that human ability to make decisions that must reflect uncertainty in one’s own motor output has limits that depend on the configuration of the gain function.

  9. Suboptimal maximum likelihood detection of on-off keying for a wireless optical communication system.

    Science.gov (United States)

    Li, Ruijie; Ding, Shengli; Dang, Anhong

    2017-05-01

    This paper investigates a detection scheme without channel state information for wireless optical communication systems. Employing conventional on-off keying signals, we supposed that conditional probability density function P(r|0) is much bigger than P(r|1) when r<0. Under this assumption, the suboptimal maximum likelihood scheme is obtained by utilizing the probability density function without channel information. Theoretical analysis shows the performance of the proposed scheme is close to the maximum likelihood symbol-by-symbol detection. Compared with the maximum likelihood symbol by symbol detection, Monte Carlo simulations show that the performance of the proposed scheme is about 0.62 dB loss for a gamma-gamma channel with a Rytov variance of 1 at the signal-to-noise ratio of 2 dB, but the efficient algorithm makes the real-time implementation of detection based on maximum likelihood feasible. Besides, the experiment is set up under 2 Gbps, and the experimental results match well with that of the theory and simulation.

  10. High-dose aspirin in addition to daily low-dose aspirin decreases platelet activation in patients before and after percutaneous coronary intervention.

    NARCIS (Netherlands)

    Berg, J.M. ten; Gerritsen, W.B.M.; Haas, F.J.L.M.; Kelder, J.C.; Verheugt, F.W.A.; Plokker, H.W.M.

    2002-01-01

    BACKGROUND: Activated platelets play a major role in acute vessel closure after coronary angioplasty. Although aspirin is the routine therapy during angioplasty, it only incompletely prevents acute closure. This might be due to suboptimal dosing. OBJECTIVE: First, to study the effect of additional

  11. Conversion coefficients for determining organ doses in paediatric spine radiography

    Energy Technology Data Exchange (ETDEWEB)

    Seidenbusch, Michael; Schneider, Karl [Ludwig-Maximilians-University of Munich, Institute of Clinical Radiology - Paediatric Radiology, Muenchen (Germany)

    2014-04-15

    Knowledge of organ and effective doses achieved during paediatric x-ray examinations is an important prerequisite for assessment of radiation burden to the patient. Conversion coefficients for reconstruction of organ and effective doses from entrance doses for segmental spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients are provided regarding the Guidelines of Good Radiographic Technique of the European Commission. Using the personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional segmental spine radiographs were calculated performing Monte Carlo simulations in mathematical hermaphrodite phantom models describing patients of different ages. The clinical variation of beam collimation was taken into consideration by defining optimal and suboptimal radiation field settings. Conversion coefficients for the reconstruction of organ doses in about 40 organs and tissues from measured entrance doses during cervical, thoracic and lumbar spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients were calculated for the standard sagittal and lateral beam projections and the standard focus detector distance of 115 cm. The conversion coefficients presented may be used for organ dose assessments from entrance doses measured during spine radiographs of patients of all age groups and all field settings within the optimal and suboptimal standard field settings. (orig.)

  12. Suboptimal herd performance amplifies the spread of infectious disease in the cattle industry.

    Directory of Open Access Journals (Sweden)

    M Carolyn Gates

    Full Text Available Farms that purchase replacement breeding cattle are at increased risk of introducing many economically important diseases. The objectives of this analysis were to determine whether the total number of replacement breeding cattle purchased by individual farms could be reduced by improving herd performance and to quantify the effects of such reductions on the industry-level transmission dynamics of infectious cattle diseases. Detailed information on the performance and contact patterns of British cattle herds was extracted from the national cattle movement database as a case example. Approximately 69% of beef herds and 59% of dairy herds with an average of at least 20 recorded calvings per year purchased at least one replacement breeding animal. Results from zero-inflated negative binomial regression models revealed that herds with high average ages at first calving, prolonged calving intervals, abnormally high or low culling rates, and high calf mortality rates were generally more likely to be open herds and to purchase greater numbers of replacement breeding cattle. If all herds achieved the same level of performance as the top 20% of herds, the total number of replacement beef and dairy cattle purchased could be reduced by an estimated 34% and 51%, respectively. Although these purchases accounted for only 13% of between-herd contacts in the industry trade network, they were found to have a disproportionately strong influence on disease transmission dynamics. These findings suggest that targeting extension services at herds with suboptimal performance may be an effective strategy for controlling endemic cattle diseases while simultaneously improving industry productivity.

  13. Suboptimal management of central nervous system infections in children: a multi-centre retrospective study

    Directory of Open Access Journals (Sweden)

    Kelly Christine

    2012-09-01

    Full Text Available Abstract Objective We aimed to audit the regional management of central nervous system (CNS infection in children. Methods The study was undertaken in five district general hospitals and one tertiary paediatric hospital in the Mersey region of the UK. Children admitted to hospital with a suspected CNS infection over a three month period were identified. Children were aged between 4 weeks and 16 years old. Details were recorded from the case notes and electronic records. We measured the appropriateness of management pathways as outlined by national and local guidelines. Results Sixty-five children were identified with a median age of 6 months (range 1 month to 15 years. Ten had a CNS infection: 4 aseptic meningitis, 3 purulent meningitis, 3 encephalitis [2 with herpes simplex virus (HSV type 1]. A lumbar puncture (LP was attempted in 50 (77% cases but only 43 had cerebrospinal fluid (CSF available for analysis. Of these 24 (57% had a complete standard set of tests performed. Fifty eight (89% received a third generation cephalosporin. Seventeen (26% also received aciclovir with no obvious indication in 9 (53%. Only 11 (65% of those receiving aciclovir had CSF herpes virus PCR. Seventeen had cranial imaging and it was the first management step in 14. Treatment lengths of both antibiotics and aciclovir were highly variable: one child with HSV encephalitis was only treated with aciclovir for 7 days. Conclusions The clinical management of children with suspected CNS infections across the Mersey region is heterogeneous and often sub-optimal, particularly for the investigation and treatment of viral encephalitis. National guidelines for the management of viral encephalitis are needed.

  14. Suboptimal vitamin K status and its risk factors in a population of Chinese chronic haemodialysis patients.

    Science.gov (United States)

    Feng, Yunlin; Ruan, Yizhe; He, Qiang; Zhang, Wensong; Wang, Li

    2015-09-01

    Vitamin K deficiency is known to be common in haemodialysis patients and associates with adverse outcomes in this population, particularly vascular calcification. We aimed to investigate the vitamin K status in a population of Chinese haemodialysis (HD) patients. We collected demographic and biochemical data from a population of maintenance HD (MHD) patients in our unit and a control group composed of healthy subjects from our outpatient clinic. Fasting serum samples from all subjects were collected for the measurement of known vitamin K-dependent proteins i.e. matrix Gla protein (MGP), osteocalcin (OC) and uncarboxylated osteocalcin (ucOC). We also quantified the fraction of ucOC to total OC (%ucOC). Differences of these parameters between groups were analyzed and risk factors of vitamin K deficiency based on the definition as per %ucOC were investigated. We enrolled 93 MHD patients as a test group and 93 healthy subjects as a control group. There was no significant difference in MGP between groups (4.0 ± 2.8 pg/mL in MHD vs 4.2 ± 1.2 pg/mL in control; P = 0.676). Mean %ucOC was significantly greater in the MHD patients as compared to control subjects (76.4 ± 20.0% in MHD vs 48.56 ± 15.5%; P vitamin K deficiency, with the former being an independent risk factor. Defining Vitamin K deficiency by %ucOC, suboptimal vitamin K levels appear common in Chinese MHD patients. Time on dialysis and LDL cholesterol level predict vitamin K deficiency. © 2015 Asian Pacific Society of Nephrology.

  15. Suboptimal porcine endogenous retrovirus infection in non-human primate cells: implication for preclinical xenotransplantation.

    Directory of Open Access Journals (Sweden)

    Giada Mattiuzzo

    Full Text Available BACKGROUND: Porcine endogenous retrovirus (PERV poses a potential risk of zoonotic infection in xenotransplantation. Preclinical transplantation trials using non-human primates (NHP as recipients of porcine xenografts present the opportunity to assess the zoonosis risk in vivo. However, PERV poorly infects NHP cells for unclear reasons and therefore NHP may represent a suboptimal animal model to assess the risk of PERV zoonoses. We investigated the mechanism responsible for the low efficiency of PERV-A infection in NHP cells. PRINCIPAL FINDINGS: Two steps, cell entry and exit, were inefficient for the replication of high-titer, human-tropic A/C recombinant PERV. A restriction factor, tetherin, is likely to be responsible for the block to matured virion release, supported by the correlation between the levels of inhibition and tetherin expression. In rhesus macaque, cynomolgus macaque and baboon the main receptor for PERV entry, PERV-A receptor 1 (PAR-1, was found to be genetically deficient: PAR-1 genes in these species encode serine at amino acid 109 in place of the leucine in human PAR-1. This genetic defect inevitably impacts in vivo sensitivity to PERV infection of these species. In contrast, African green monkey (AGM PAR-1 is functional, but PERV infection is still poor. Although the mechanism is unclear, tunicamycin treatment, which removes N-glycosylated sugar chains, increases PERV infection, suggesting a possible role for the glycosylation of the receptors. CONCLUSIONS: Since cynomolgus macaque and baboon, species often used in pig-to-NHP xenotransplantation experiments, have a defective PAR-1, they hardly represent an ideal animal model to assess the risk of PERV transmission in xenotransplantation. Alternatively, NHP species, like AGM, whose both PARs are functional may represent a better model than baboon and cynomolgus macaque for PERV zoonosis in vivo studies.

  16. Sensor-augmented pump therapy lowers HbA(1c) in suboptimally controlled Type 1 diabetes; a randomized controlled trial

    DEFF Research Database (Denmark)

    Hermanides, J; Nørgaard, K; Bruttomesso, D

    2011-01-01

    To investigate the efficacy of sensor-augmented pump therapy vs. multiple daily injection therapy in patients with suboptimally controlled Type 1 diabetes.......To investigate the efficacy of sensor-augmented pump therapy vs. multiple daily injection therapy in patients with suboptimally controlled Type 1 diabetes....

  17. Low dose aspirin and pregnancy: how important is aspirin resistance?

    OpenAIRE

    Navaratnam, K; Alfirevic, A; Alfirevic, Z

    2016-01-01

    Antiplatelet agents are pivotal for prevention of coronary artery disease and cerebrovascular disease worldwide. Individual patient data meta?analysis indicates that low?dose aspirin causes a 10% risk reduction in pre?eclampsia for women at high individual risk. However, in the last 15 years it has emerged that a significant proportion of aspirin?treated individuals exhibit suboptimal platelet response, determined biochemically and clinically, termed ?aspirin non?responsiveness?, ?aspirin res...

  18. Real-time discrete suboptimal control for systems with input and state delays: Experimental tests on a dehydration process.

    Science.gov (United States)

    Rodríguez-Guerrero, Liliam; Santos-Sánchez, Omar-Jacobo; Cervantes-Escorcia, Nicolás; Romero, Hugo

    2017-11-01

    This article presents a suboptimal control strategy with finite horizon for affine nonlinear discrete systems with both state and input delays. The Dynamic Programming Approach is used to obtain the suboptimal control sequence, but in order to avoid the computation of the Bellman functional, a numerical approximation of this function is proposed in every step. The feasibility of our proposal is demonstrated via an experimental test on a dehydration process and the obtained results show a good performance and behavior of this process. Then in order to demonstrate the benefits of using this kind of control strategy, the results are compared with a non optimal control strategy, particularly with respect to results produced by an industrial Proportional Integral Derivative (PID) Honeywell controller, which is tuned using the Ziegler-Nichols method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Consumer behaviour towards price-reduced suboptimal foods in the supermarket and the relation to food waste in households.

    Science.gov (United States)

    Aschemann-Witzel, Jessica; Jensen, Jacob Haagen; Jensen, Mette Hyldetoft; Kulikovskaja, Viktorija

    2017-09-01

    To combat food waste, supermarkets offer food items at a reduced price in-store when they are close to the expiration date or perceived as suboptimal. It is yet unknown, however, which considerations consumers engage in when deciding about the offer, and whether focusing particularly on the price during food purchase might be related to greater food waste at home. Knowledge about both the consumers' food purchase process for these price-reduced foods and the potential wastage of price-focused consumers can contribute to the assessment of whether or not offering suboptimal food at reduced prices in-store actually reduces food waste across the supply chain. We explore these questions in a mixed-method study including 16 qualitative accompanied shopping interviews and a quantitative online experimental survey with 848 consumers in Denmark. The interviews reveal that the consumers interviewed assess their ability to consume the price-reduced suboptimal food at home already while in the store. Consumers consider the relation between product-related factors of package unit, expiration date, and product quality, in interaction with household-related factors of freezing/storing, household size/demand, and possible meal/cooking. The survey shows that consumers who are more price-focused report lower food waste levels and lower tendency to choose the optimal food item first at home, than those who are not emphasizing the price-quality relation or do not search for price offers to the same extent. Higher age and high education also played a role, and the price-focus is lower in high-income groups and among single households. The findings allow deriving recommendations for retailers and policy makers to support both the marketability and the subsequent actual consumption of price-reduced suboptimal food, but they also raise questions for further research of this underexplored area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Dyslipidemia is not associated with cardiovascular disease risk in an animal model of mild chronic suboptimal nutrition.

    Science.gov (United States)

    Lifshitz, Fima; Pintos, Patricia M; Lezón, Christian E; Macri, Elisa V; Friedman, Silvia M; Boyer, Patricia M

    2012-01-01

    Previous studies performed in an experimental model of nutritional growth retardation (NGR) have observed metabolic adaptation. We hypothesized that changes in lipid-lipoprotein profile, glucose, and insulin levels occur, whereas overall body growth is reduced.The aim of this study was to assess serum lipid-lipoprotein profile, hepatogram, insulinemia and glycemia, and CVD risk markers in rats fed a suboptimal diet. Weanling male rats were assigned either to control (C) or NGR group. In this 4-week study, C rats were fed ad libitum a standard diet, and NGR rats received 80% of the amount of food consumed by C. Zoometric parameters, body fat content, serum lipid-lipoprotein profile, hepatogram, insulinemia, and glycemia were determined, and the cardiovascular disease (CVD) risk markers homeostasis model assessment-insulin resistance and homeostasis model assessment and β-cell function were calculated. Suboptimal food intake induced a significant decrease in body weight and length, which were accompanied by a reduction of 50% in body fat mass. Serum lipoproteins were significantly higher in NGR rats, with the exception of high-density lipoprotein cholesterol, which remained unchanged. Nutritional growth retardation rats had decreased triglycerides compared with C rats. No significant differences were detected in liver function parameters. The CVD risk markers homeostasis model assessment (HOMA)-insulin resistance and homeostasis model assessment and β-cell function were significantly lower in NGR rats. Mild chronic suboptimal nutrition in weanling male rats led to growth retardation and changes in the lipid-lipoprotein profile, glucose, and insulin levels while preserving the integrity of liver function. These data suggest a metabolic adaptation during suboptimal food intake, which ensures substrates flux to tissues that require constant energy-in detriment to body growth. The CVD risk markers suggested that mild chronic food restriction of approximately 20% could

  1. Rising burden of gout in the UK but continuing suboptimal management: a nationwide population study

    Science.gov (United States)

    Kuo, Chang-Fu; Grainge, Matthew J; Mallen, Christian; Zhang, Weiya; Doherty, Michael

    2015-01-01

    Objectives To describe trends in the epidemiology of gout and patterns of urate-lowering treatment (ULT) in the UK general population from 1997 to 2012. Methods We used the Clinical Practice Research Datalink to estimate the prevalence and incidence of gout for each calendar year from 1997 to 2012. We also investigated the pattern of gout management for both prevalent and incident gout patients. Results In 2012, the prevalence of gout was 2.49% (95% CI 2.48% to 2.51%) and the incidence was 1.77 (95% CI 1.73 to 1.81) per 1000 person-years. Prevalence and incidence both were significantly higher in 2012 than in 1997, with a 63.9% increase in prevalence and 29.6% increase in incidence over this period. Regions with highest prevalence and incidence were the North East and Wales. Among prevalent gout patients in 2012, only 48.48% (95% CI 48.08% to 48.89%) were being consulted specifically for gout or treated with ULT and of these 37.63% (95% CI 37.28% to 38.99%) received ULT. In addition, only 18.6% (95% CI 17.6% to 19.6%) of incident gout patients received ULT within 6 months and 27.3% (95% CI 26.1% to 28.5%) within 12 months of diagnosis. The management of prevalent and incident gout patients remained essentially the same during the study period, although the percentage of adherent patients improved from 28.28% (95% CI 27.33% to 29.26%) in 1997 to 39.66% (95% CI 39.11% to 40.22%) in 2012. Conclusions In recent years, both the prevalence and incidence of gout have increased significantly in the UK. Suboptimal use of ULT has not changed between 1997 and 2012. Patient adherence has improved during the study period, but it remains poor. PMID:24431399

  2. Inadequate doses of hemodialysis. Predisposing factors, causes and prevention

    Directory of Open Access Journals (Sweden)

    Pehuén Fernández

    2017-04-01

    Full Text Available Patients receiving sub-optimal dose of hemodialysis have increased morbidity and mortality. The objectives of this study were to identify predisposing factors and causes of inadequate dialysis, and to design a practical algorithm for the management of these patients. A cross-sectional study was conducted. Ninety patients in chronic hemodialysis at Hospital Privado Universitario de Córdoba were included, during September 2015. Twenty two received sub-optimal dose of hemodialysis. Those with urea distribution volume (V greater than 40 l (72 kg body weight approximately are 11 times more likely (OR = 11.6; CI 95% = 3.2 to 51.7, p < 0.0001 to receive an inadequate dose of hemodialysis, than those with a smaller V. This situation is more frequent in men (OR = 3.5; 95% CI 1.01-15.8; p = 0.0292. V greater than 40 l was the only independent predictor of sub-dialysis in the multivariate analysis (OR = 10.3; 95% CI 2.8-37; p < 0.0004. The main cause of suboptimal dialysis was receiving a lower blood flow (Qb than the prescribed (336.4 ± 45.8 ml/min vs. 402.3 ± 28.8 ml/min respectively, p < 0.0001 (n = 18. Other causes were identified: shorter duration of the session (n = 2, vascular access recirculation (n = 1, and error in the samples (n = 1. In conclusion, the only independent predisposing factor found in this study for sub-optimal dialysis is V greater than 40 l. The main cause was receiving a slower Qb than prescribed. From these findings, an algorithm for the management of these patients was developed

  3. Dose optimization of intra-operative high dose rate interstitial brachytherapy implants for soft tissue sarcoma

    Directory of Open Access Journals (Sweden)

    Jamema Swamidas

    2009-01-01

    Full Text Available Objective : A three dimensional (3D image-based dosimetric study to quantitatively compare geometric vs. dose-point optimization in combination with graphical optimization for interstitial brachytherapy of soft tissue sarcoma (STS. Materials and Methods : Fifteen consecutive STS patients, treated with intra-operative, interstitial Brachytherapy, were enrolled in this dosimetric study. Treatment plans were generated using dose points situated at the "central plane between the catheters", "between the catheters throughout the implanted volume", at "distances perpendicular to the implant axis" and "on the surface of the target volume" Geometrically optimized plans had dose points defined between the catheters, while dose-point optimized plans had dose points defined at a plane perpendicular to the implant axis and on the target surface. Each plan was graphically optimized and compared using dose volume indices. Results : Target coverage was suboptimal with coverage index (CI = 0.67 when dose points were defined at the central plane while it was superior when the dose points were defined at the target surface (CI=0.93. The coverage of graphically optimized plans (GrO was similar to non-GrO with dose points defined on surface or perpendicular to the implant axis. A similar pattern was noticed with conformity index (0.61 vs. 0.82. GrO were more conformal and less homogeneous compared to non-GrO. Sum index was superior for dose points defined on the surface of the target and relatively inferior for plans with dose points at other locations (1.35 vs. 1.27. Conclusions : Optimization with dose points defined away from the implant plane and on target results in superior target coverage with optimal values of other indices. GrO offer better target coverage for implants with non-uniform geometry and target volume.

  4. Adjusting eptifibatide doses for renal impairment: a model of dosing agreement among various methods of estimating creatinine clearance.

    Science.gov (United States)

    Healy, Martha F; Speroni, Karen Gabel; Eugenio, Kenneth R; Murphy, Patricia M

    2012-04-01

    Because of the renal elimination and increased risk for bleeding events at supratherapeutic doses of eptifibatide, the manufacturer recommends dosing adjustment in patients with renal dysfunction. Methods commonly used to estimate renal dysfunction in hospital settings may be inconsistent with those studied and recommended by the manufacturer. To compare hypothetical renal dosing adjustments of eptifibatide using both the recommended method and several other commonly used formulas for estimating kidney function. Sex, age, weight, height, serum creatinine, and estimated glomerular filtration rate (eGFR) were obtained retrospectively from the records of patients who received eptifibatide during a 12-month period. Renal dosing decisions were determined for each patient based on creatinine clearance (CrCl) estimates via the Cockcroft-Gault formula (CG) with actual body weight (ABW), ideal body weight (IBW) or adjusted weight (ADJW), and eGFR from the Modification of Diet in Renal Disease formula. Percent agreement and Cohen κ were calculated comparing dosing decisions for each formula to the standard CG-ABW. In this analysis of 179 patients, percent agreement as compared to CG-ABW varied (CG-IBW: 90.50%, CG-ADJW: 95.53%, and eGFR: 93.30%). All κ coefficients were categorized as good. In the 20% of patients receiving an adjusted dose by any of the methods, 68.6% could have received a dose different from that determined using the CG-ABW formula. In the patients with renal impairment (CrCl eptifibatide doses in patients with renal impairment has led to increased bleeding events, practitioners may be inclined to err on the side of caution. However, studies have shown that suboptimal doses of eptifibatide lead to suboptimal outcomes. Therefore, correct dosing of eptifibatide is important to both patient safety and efficacy.

  5. Addition of neutral protamine lispro insulin or insulin glargine to oral type 2 diabetes regimens for patients with suboptimal glycemic control: a randomized trial.

    Science.gov (United States)

    Esposito, Katherine; Ciotola, Miryam; Maiorino, Maria Ida; Gualdiero, Roberto; Schisano, Bruno; Ceriello, Antonio; Beneduce, Flora; Feola, Giovanni; Giugliano, Dario

    2008-10-21

    Injection of long-acting insulin at bedtime is a common therapeutic approach for patients with type 2 diabetes that is poorly controlled with oral regimens. Neutral protamine lispro (NPL) insulin has demonstrated better glycemic control and similar incidence of hypoglycemic events than that of neutral protamine Hagedorn insulin. To compare the clinical efficacy and safety of bedtime NPL insulin or insulin glargine in patients with type 2 diabetes who had suboptimal glycemic control while receiving stable doses of metformin and sulfonylurea. Open-label, randomized trial. Teaching hospital (Azienda Ospedaliera Universitaria, Second University of Naples), Naples, Italy. 116 adults receiving stable doses of metformin plus sulfonylurea for longer than 90 days with hemoglobin A(1c) (HbA(1c)) levels of 7.5% to 10% and fasting plasma glucose levels of 6.7 mmol/L or greater (> or =120 mg/dL). 10 IU of NPL insulin or insulin glargine injected subcutaneously at bedtime with weekly dose titrations to target fasting glucose levels less than 5.6 mmol/L (weight. Twenty patients in each group had continuous glucose monitoring for 3 consecutive days before adding insulin and at week 36. Improvement in HbA(1c) levels was similar in both groups (1.83% and 1.89% for NPL and glargine, respectively). The difference between the groups was 0.06 percentage point (95% CI, -0.1 to 0.15 percentage points). Secondary outcomes did not differ between groups. Hemoglobin A(1c) levels less than 7% occurred in 62% of patients receiving NPL and 64% of patients receiving glargine (difference, 2.0 percentage points [CI, -1.1 to 5.0 percentage points]). Fasting plasma glucose levels less than 5.6 mmol/L (<100 mg/dL) occurred in 40% of patients receiving NPL and 41% of patients receiving glargine (difference, 1.0 percentage point [CI, -0.9 to 3.0 percentage points]). Any hypoglycemic event occurred in 74% of patients receiving NPL and 67% of patients receiving glargine (difference, 7 percentage points

  6. Patterns of marijuana and tobacco use associated with suboptimal self-rated health among US adult ever users of marijuana

    OpenAIRE

    Tsai, James; Rolle, Italia V.; Singh, Tushar; Sheree L. Boulet; McAfee, Timothy A.; Grant, Althea M.

    2017-01-01

    The purpose of this study was to examine the patterns of marijuana and tobacco use and their associations with suboptimal self-rated health (SRH) among US adults who reported ?ever, even once, using marijuana or hashish.? Data came from the 2009?2012 National Health and Nutrition Examination Survey, restricting to respondents aged 20 years and older who reported using marijuana at least once in their lifetime (n?=?3,210). We assessed the age-adjusted prevalence of mutually exclusive groups of...

  7. LAM add-on ADV combination therapy or ETV monotherapy for CHB patients with suboptimal response to ADV.

    Science.gov (United States)

    Jia, Hongyu; Ding, Feng; Chen, Jianyang; Zhang, Yimin; Xiang, Dairong; Lian, Jiangshan; Zeng, Linyan; Yu, Liang; Hu, Jianhua; Li, Yongtao; Lu, Yingfeng; Liu, Yuanchun; Zheng, Lin; Li, Lanjuan; Yang, Yida

    2015-01-01

    Among the available nucleos(t)ide analogues adefovir dipivoxil (ADV) is relatively cheap and widely used in rural area in China. However, there are insufficient data on recommendation for patients with suboptimal response to ADV after 48 weeks of treatment in order to reduce the resistance rate in the long term. The aim of this study was to compare the efficacy and safety of LAM add-on combination therapy versus ETV monotherapy for patients with suboptimal response to ADV. 136 patients with suboptimal response to ADV were randomly assigned to the add-on LAM with ADV combination therapy (68 patients) group and the ETV monotherapy (68 patients) group. Patients in the add-on group were prescribed 100 mg LAM and 10 mg ADV per day, while the monotherapy group received 0.5 mg ETV per day for 48 weeks. Tests for liver and kidney function, HBV serum markers, HBV DNA load, were performed every 3 months. The mean patient age in LAM add-on group and ETV monotherapy was 38.59 ± 7.65 and 37.56 ± 8.67 years respectively. The HBV DNA undetectable rate in the LAM add-on group and the ETV group were not significant difference at week 4, 12 and 24 (P > 0.05). However, the HBV undetectable rate in the ETV group was higher than that in the LAM add-on group at week 36 and 48 (P = 0.043 for week 36 and P = 0.038 for week 48). There was no significant difference both for HBeAg loss and HBeAg seroconversion between two groups (P > 0.05) at 48 weeks. Meanwhile, our study also demonstrated that the mean eGFR levels in LAM add-on group was decreased from 99.6 ± 8.71 at baseline to 86.4 ± 9.83 at the end of 48 weeks, which was significantly higher than that in the ETV monotherapy group (P add-on group experienced eGFR reduction by 20-30% from baseline at 48 weeks. No patients developed hyposphosphatemia in our study. Our study clearly showed that switch to ETV monotherapy was the more effective and more safe than that of LAM add-on combination therapy for patients with suboptimal response

  8. Rootstock Sub-Optimal Temperature Tolerance Determines Transcriptomic Responses after Long-Term Root Cooling in Rootstocks and Scions of Grafted Tomato Plants

    OpenAIRE

    Georgia Ntatsi; Dimitrios Savvas; Vassilis Papasotiropoulos; Anastasios Katsileros; Zrenner, Rita M.; Hincha, Dirk K.; Ellen Zuther; Dietmar Schwarz

    2017-01-01

    Grafting of elite cultivars onto tolerant rootstocks is an advanced strategy to increase tomato tolerance to sub-optimal temperature. However, a detailed understanding of adaptive mechanisms to sub-optimal temperature in rootstocks and scions of grafting combinations on a physiological and molecular level is lacking. Here, the commercial cultivar Kommeet was grafted either onto ‘Moneymaker’ (sensitive) or onto the line accession LA 1777 of Solanum habrochaites (tolerant). Grafted plants were ...

  9. Risk factors and morbidity associated with suboptimal instrument placement at instrumental delivery: observational study nested within the Instrumental Delivery & Ultrasound randomised controlled trial ISRCTN 72230496.

    Science.gov (United States)

    Ramphul, M; Kennelly, M M; Burke, G; Murphy, D J

    2015-03-01

    To identify risk factors and morbidity associated with suboptimal instrument placement at instrumental delivery. Observational study, nested within a randomised controlled trial. Two university-affiliated maternity hospitals. A cohort of 478 nulliparous women at term (≥37 weeks of gestation) undergoing instrumental delivery. Univariable and multivariable logistic regression analyses were performed. Risk factors for suboptimal application of vacuum or forceps, maternal and neonatal morbidity, and the sequential use of instruments, second operator, and caesarean section following failed instrumental delivery. Instrument placement was suboptimal in 138 of 478 (28.8%) deliveries. Factors associated with suboptimal instrument placement included fetal malposition (OR 2.44, 95% CI 1.62-3.66), mid-cavity station (OR 1.68, 95% CI 1.02-2.78), and forceps as the primary instrument (OR 2.01, 95% CI 1.33-3.04). Compared with optimal instrument placement, suboptimal placement was associated with prolonged hospital stay (adjusted OR 2.28, 95% CI 1.30-4.02) and neonatal trauma (adjusted OR 4.25, 95% CI 1.85-9.72). Suboptimal placement was associated with a greater use of sequential instruments (adjusted OR 3.99, 95% CI 1.94-8.23) and caesarean section for failed instrumental delivery (adjusted OR 3.81, 95% CI 1.10-13.16). The mean decision to delivery interval (DDI) was 4 minutes longer in the suboptimal group (95% CI 2.1-5.9 minutes). Suboptimal instrument placement is associated with increased maternal and neonatal morbidity and procedural complications. Greater attention should be focused on instrument placement when training obstetricians for instrumental delivery. © 2014 Royal College of Obstetricians and Gynaecologists.

  10. Optimal and Suboptimal Finger Selection Algorithms for MMSE Rake Receivers in Impulse Radio Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Chiang Mung

    2006-01-01

    Full Text Available The problem of choosing the optimal multipath components to be employed at a minimum mean square error (MMSE selective Rake receiver is considered for an impulse radio ultra-wideband system. First, the optimal finger selection problem is formulated as an integer programming problem with a nonconvex objective function. Then, the objective function is approximated by a convex function and the integer programming problem is solved by means of constraint relaxation techniques. The proposed algorithms are suboptimal due to the approximate objective function and the constraint relaxation steps. However, they perform better than the conventional finger selection algorithm, which is suboptimal since it ignores the correlation between multipath components, and they can get quite close to the optimal scheme that cannot be implemented in practice due to its complexity. In addition to the convex relaxation techniques, a genetic-algorithm- (GA- based approach is proposed, which does not need any approximations or integer relaxations. This iterative algorithm is based on the direct evaluation of the objective function, and can achieve near-optimal performance with a reasonable number of iterations. Simulation results are presented to compare the performance of the proposed finger selection algorithms with that of the conventional and the optimal schemes.

  11. Application of the tuning algorithm with the least squares approximation to the suboptimal control algorithm for integrating objects

    Science.gov (United States)

    Kuzishchin, V. F.; Merzlikina, E. I.; Van Va, Hoang

    2017-11-01

    The problem of PID and PI-algorithms tuning by means of the approximation by the least square method of the frequency response of a linear algorithm to the sub-optimal algorithm is considered. The advantage of the method is that the parameter values are obtained through one cycle of calculation. Recommendations how to choose the parameters of the least square method taking into consideration the plant dynamics are given. The parameters mentioned are the time constant of the filter, the approximation frequency range and the correction coefficient for the time delay parameter. The problem is considered for integrating plants for some practical cases (the level control system in a boiler drum). The transfer function of the suboptimal algorithm is determined relating to the disturbance that acts in the point of the control impact input, it is typical for thermal plants. In the recommendations it is taken into consideration that the overregulation for the transient process when the setpoint is changed is also limited. In order to compare the results the systems under consideration are also calculated by the classical method with the limited frequency oscillation index. The results given in the paper can be used by specialists dealing with tuning systems with the integrating plants.

  12. Tuber melanosporum spread within sub-optimal climatic zones is controlled by fruiting triggers and not mycorrhiza survival

    Directory of Open Access Journals (Sweden)

    Paul W. Thomas

    2014-07-01

    Full Text Available Tuber melanosporum is the most valuable of all cultivatable truffle species. Farming of this species spans every continent with the exception of Antarctica. Tuber aestivum (syn. T. uncinatum and Tuber brumale are truffle species that have similar host plant preference and a similar affinity for calcareous soils as T. melanosporum, but occur over a broader geographic zone. The geographic limit of T. melanosporum is thought to be climatically dictated but it is not known whether this is due to an impact on mycorrhizal survival or climatically-derived fruiting triggers. Here, data is compiled from five cultivated research sites in the climatically sub-optimal conditions of the UK in order to address this question. Here we show: (iTuber melanosporum mycorrhiza can survive and grow in sub-optimal climatic conditions. (iiIt is climatically-derived fruiting triggers and not ectomycorrhiza survival that dictate the climatic preferences and geographic spread of T. melanosporum. (iiiImportant climatic parameters for potential fruiting triggers are sunshine hours, summer rainfall and summer temperatures.   The data presented here not only aid our understanding of the ecological parameters of T. melanosporum but also have a practical application for truffle cultivators in choosing suitable locations for a plantation.

  13. Traditional Chinese medicine and new concepts of predictive, preventive and personalized medicine in diagnosis and treatment of suboptimal health.

    Science.gov (United States)

    Wang, Wei; Russell, Alyce; Yan, Yuxiang

    2014-02-13

    The premise of disease-related phenotypes is the definition of the counterpart normality in medical sciences. Contrary to clinical practices that can be carefully planned according to clinical needs, heterogeneity and uncontrollability is the essence of humans in carrying out health studies. Full characterization of consistent phenotypes that define the general population is the basis to individual difference normalization in personalized medicine. Self-claimed normal status may not represent health because asymptomatic subjects may carry chronic diseases at their early stage, such as cancer, diabetes mellitus and atherosclerosis. Currently, treatments for non-communicable chronic diseases (NCD) are implemented after disease onset, which is a very much delayed approach from the perspective of predictive, preventive and personalized medicine (PPPM). A NCD pandemic will develop and be accompanied by increased global economic burden for healthcare systems throughout both developed and developing countries. This paper examples the characterization of the suboptimal health status (SHS) which represents a new PPPM challenge in a population with ambiguous health complaints such as general weakness, unexplained medical syndrome (UMS), chronic fatigue syndrome (CFS), myalgic encephalomyelitis (ME), post-viral fatigue syndrome (PVFS) and chronic fatigue immune dysfunction syndrome (CFIDS). We applied clinical informatic approaches and developed a questionnaire-suboptimal health status questionnaire-25 (SHSQ-25) for measuring SHS. The validity and reliability of this approach were evaluated in a small pilot study and then in a cross-sectional study of 3,405 participants in China. We found a correlation between SHS and systolic blood pressure, diastolic blood pressure, plasma glucose, total cholesterol and high-density lipoprotein (HDL) cholesterol among men, and a correlation between SHS and systolic blood pressure, diastolic blood pressure, total cholesterol, triglycerides

  14. Activation Layer Stabilization of High Polarization Photocathodes in Sub-Optimal RF Gun Environments

    Energy Technology Data Exchange (ETDEWEB)

    Gregory A. Mulhollan

    2010-11-16

    Specific activation recipes for bulk, 100 nm thick MBE grown and high polarization III-V photocathode material have been developed which mitigate the effects of exposure to background gasses. Lifetime data using four representative gasses were acquired for bulk GaAs, 100 nm unstrained GaAs and strained superlattice GaAs/GaAsP, all activated both with Cs and then Cs and Li (bi-alkali). Each photoemitter showed marked resilience improvement when activated using the bi-alkali recipe compared to the standard single alkali recipe. A dual alkali activation system at SLAC was constructed, baked and commissioned with the purpose of performing spin-polarization measurements on electrons emitted from the bi-alkali activated surfaces. An end station at SSRL was configured with the required sources for energy resolved photoemission measurements on the bi-alkali activated and CO2 dosed surfaces. The bi-alkali recipes were successfully implemented at SLAC/SSRL. Measurements at SLAC of the photoelectron spin-polarization from the modified activation surface showed no sign of a change in value compared to the standard activated material, i.e., no ill effects. Analysis of photoemission data indicates that the addition of Li to the activation layer results in a multi-layer structure. The presence of Li in the activation layer also acts as an inhibitor to CO2 absorption, hence better lifetimes in worse vacuum were achieved. The bi-alkali activation has been tested on O2 activated GaAs for comparison with NF3 activated surfaces. Comparable resilience to CO2 exposure was achieved for the O2 activated surface. An RF PECVD amorphous silicon growth system was modified to allow high temperature heat cleaning of GaAs substrates prior to film deposition. Growth versus thickness data were collected. Very thin amorphous silicon germanium layers were optimized to exhibit good behavior as an electron emitter. Growth of the amorphous silicon germanium films on the above substrates was fine tuned

  15. Consumer perception and preference for suboptimal food under the emerging practice of expiration date based pricing in supermarkets

    DEFF Research Database (Denmark)

    Aschemann-Witzel, Jessica

    2017-01-01

    Consumers have been found to majorly prefer ‘optimal’ food over ‘suboptimal’ when purchasing food. To provide an incentive for consumers to select suboptimal food and thus decrease food waste in the supply chain, expiration date based pricing is suggested and increasingly applied. However......, individual preferences, and product-related factors. An online survey experiment among 842 Danish consumers realistically mimicked the current market context. Findings reveal that neither communicating budget saving or food waste avoidance nor the product being organic has an influence. However......, there is a gender effect when the practice is communicated as a food waste avoidance action. Consumer’s familiarity with the practice has a significant influence, as has the individual giving importance to the price criterion, age, and education. Food category differences are explored, showing that familiarity...

  16. Two Liters a Day Keep the Doctor Away? Considerations on the Pathophysiology of Suboptimal Fluid Intake in the Common Population.

    Science.gov (United States)

    Lang, Florian; Guelinckx, Isabelle; Lemetais, Guillaume; Melander, Olle

    2017-01-01

    Suboptimal fluid intake may require enhanced release of antidiuretic hormone (ADH) or vasopressin for the maintenance of adequate hydration. Enhanced copeptin levels (reflecting enhanced vasopressin levels) in 25% of the common population are associated with enhanced risk of metabolic syndrome with abdominal obesity, type 2 diabetes, hypertension, coronary artery disease, heart failure, vascular dementia, cognitive impairment, microalbuminuria, chronic kidney disease, inflammatory bowel disease, cancer, and premature mortality. Vasopressin stimulates the release of glucocorticoids which in turn up-regulate the serum- and glucocorticoid-inducible kinase 1 (SGK1). Moreover, dehydration upregulates the transcription factor NFAT5, which in turn stimulates SGK1 expression. SGK1 is activated by insulin, growth factors and oxidative stress via phosphatidylinositide-3-kinase, 3-phosphoinositide-dependent kinase PDK1 and mTOR. SGK1 is a powerful stimulator of Na+/K+-ATPase, carriers (e.g. the Na+,K+,2Cl- cotransporter NKCC, the NaCl cotransporter NCC, the Na+/H+ exchanger NHE3, and the Na+ coupled glucose transporter SGLT1), and ion channels (e.g. the epithelial Na+ channel ENaC, the Ca2+ release activated Ca2+ channel Orai1 with its stimulator STIM1, and diverse K+ channels). SGK1 further participates in the regulation of the transcription factors nuclear factor kappa-B NFκB, p53, cAMP responsive element binding protein (CREB), activator protein-1, and forkhead transcription factor FKHR-L1 (FOXO3a). Enhanced SGK1 activity fosters the development of hypertension, obesity, diabetes, thrombosis, stroke, inflammation including inflammatory bowel disease and autoimmune disease, cardiac fibrosis, proteinuria, renal failure as well as tumor growth. The present brief review makes the case that suboptimal fluid intake in the common population may enhance vasopressin and glucocorticoid levels thus up-regulating SGK1 expression and favouring the development of SGK1 related

  17. Hyperplastic obesity and liver steatosis as long-term consequences of suboptimal in vitro culture of mouse embryos.

    Science.gov (United States)

    Serrano, Antonia; Decara, Juan M; Fernández-González, Raúl; López-Cardona, Angela P; Pavón, Francisco J; Orio, Laura; Alen, Francisco; Gutiérrez-Adán, Alfonso; de Fonseca, Fernando Rodríguez

    2014-08-01

    In the present study, we identify and describe an obese phenotype in mice as a long-term consequence of a suboptimal in vitro culture that resulted from the addition of fetal calf serum (FCS) into the culture medium. Mice produced with FCS displayed a high mortality rate (approximately 55% versus 15% in control mice within 20 mo) and increased sensitivity to the development of obesity in adulthood when fed either a standard or a high-fat diet. These mice developed hyperplastic obesity that was characterized by a significant expansion of the fat pads (approximately 25% and 32% higher body weight in male and female mice over controls, respectively) with unchanged adipocyte size. We observed a sexual dimorphism in the development of obesity in the mice produced with FCS. Whereas the female mice displayed hypertension, hyperleptinemia, and fatty liver, the male mice only displayed glucose intolerance. The mRNA expression of metabolically relevant genes in the adipose tissue was also affected. The males produced with FCS expressed higher mRNA levels of the genes that activate fatty acid oxidation (peroxisome proliferator-activated receptor alpha [Ppara, PPARalpha] and acyl-CoA oxidase 1 [Acox1, ACOX1]) and thermogenesis (uncoupling protein 1 [Ucp1, UCP1]), which may counteract the metabolic phenotype. Conversely, the females produced with FCS generally expressed lower levels of these metabolic genes. In the females, the obese phenotype was associated with inhibition of the lipogenic pathway (peroxisome proliferator-activated receptor gamma [Pparg, PPARgamma] and fatty acid synthase [Fasn, FAS]), indicating a saturation of the storage capacity of the adipose tissue. Overall, our data indicate that the exposure to suboptimal in vitro culture conditions can lead to the sexually dimorphic development of obesity in adulthood. © 2014 by the Society for the Study of Reproduction, Inc.

  18. Sickness presenteeism predicts suboptimal self-rated health and sickness absence: a nationally representative study of the Swedish working population.

    Directory of Open Access Journals (Sweden)

    Marina Taloyan

    Full Text Available BACKGROUND: Earlier studies have suggested that sickness presenteeism (SP may be a risk factor for future health problems. The purpose of the present study was to test this in a nationally representative prospective study of Swedish workers. METHODS: Prospective cohort with a representative sample of the Swedish working population surveyed in 2008 and 2010. Odds ratios (OR with 95% confidence intervals (CI were calculated using logistic regression. RESULTS: Those who reported more than 7 days of SP had higher risk of suboptimal SRH compared to those who reported no SP (OR = 5.95; 95% CI 4.98-7.12, also after adjustment for confounders (OR = 1.64; 95% CI 1.30-2.06. Those who reported 1-7 days of SP also had an increased risk before and after adjustments. Inclusion of self-rated physical and psychological work capacity did not attenuate the associations, whereas of emotional exhaustion attenuated the ORs to non-significance for both outcomes, indicating that the health consequences associated with SP are largely related to mental health. CONCLUSION: The results strengthen earlier findings suggesting that SP can be a risk factor for future suboptimal general health and sickness absence, particularly through mental health problems. This indicates that asking about SP could yield important information for employers, occupational health practitioners and GPs, possibly leading to more timely intervention that could decrease the risk of future sickness absence and more serious health problems, especially in the mental domain. Further studies of the possible causal pathways between SP and future health development are also warranted, especially since going to work is often seen as desirable also for those with poor health.

  19. Sickness Presenteeism Predicts Suboptimal Self-Rated Health and Sickness Absence: A Nationally Representative Study of the Swedish Working Population

    Science.gov (United States)

    Taloyan, Marina; Aronsson, Gunnar; Leineweber, Constanze; Magnusson Hanson, Linda; Alexanderson, Kristina; Westerlund, Hugo

    2012-01-01

    Background Earlier studies have suggested that sickness presenteeism (SP) may be a risk factor for future health problems. The purpose of the present study was to test this in a nationally representative prospective study of Swedish workers. Methods Prospective cohort with a representative sample of the Swedish working population surveyed in 2008 and 2010. Odds ratios (OR) with 95% confidence intervals (CI) were calculated using logistic regression. Results Those who reported more than 7 days of SP had higher risk of suboptimal SRH compared to those who reported no SP (OR = 5.95; 95% CI 4.98–7.12), also after adjustment for confounders (OR = 1.64; 95% CI 1.30–2.06). Those who reported 1–7 days of SP also had an increased risk before and after adjustments. Inclusion of self-rated physical and psychological work capacity did not attenuate the associations, whereas of emotional exhaustion attenuated the ORs to non-significance for both outcomes, indicating that the health consequences associated with SP are largely related to mental health. Conclusion The results strengthen earlier findings suggesting that SP can be a risk factor for future suboptimal general health and sickness absence, particularly through mental health problems. This indicates that asking about SP could yield important information for employers, occupational health practitioners and GPs, possibly leading to more timely intervention that could decrease the risk of future sickness absence and more serious health problems, especially in the mental domain. Further studies of the possible causal pathways between SP and future health development are also warranted, especially since going to work is often seen as desirable also for those with poor health. PMID:22984547

  20. Two Liters a Day Keep the Doctor Away? Considerations on the Pathophysiology of Suboptimal Fluid Intake in the Common Population

    Directory of Open Access Journals (Sweden)

    Florian Lang

    2017-08-01

    Full Text Available Suboptimal fluid intake may require enhanced release of antidiuretic hormone (ADH or vasopressin for the maintenance of adequate hydration. Enhanced copeptin levels (reflecting enhanced vasopressin levels in 25% of the common population are associated with enhanced risk of metabolic syndrome with abdominal obesity, type 2 diabetes, hypertension, coronary artery disease, heart failure, vascular dementia, cognitive impairment, microalbuminuria, chronic kidney disease, inflammatory bowel disease, cancer, and premature mortality. Vasopressin stimulates the release of glucocorticoids which in turn up-regulate the serum- and glucocorticoid-inducible kinase 1 (SGK1. Moreover, dehydration upregulates the transcription factor NFAT5, which in turn stimulates SGK1 expression. SGK1 is activated by insulin, growth factors and oxidative stress via phosphatidylinositide-3-kinase, 3-phosphoinositide-dependent kinase PDK1 and mTOR. SGK1 is a powerful stimulator of Na+/K+-ATPase, carriers (e.g. the Na+,K+,2Cl- cotransporter NKCC, the NaCl cotransporter NCC, the Na+/H+ exchanger NHE3, and the Na+ coupled glucose transporter SGLT1, and ion channels (e.g. the epithelial Na+ channel ENaC, the Ca2+ release activated Ca2+ channel Orai1 with its stimulator STIM1, and diverse K+ channels. SGK1 further participates in the regulation of the transcription factors nuclear factor kappa-B NFκB, p53, cAMP responsive element binding protein (CREB, activator protein-1, and forkhead transcription factor FKHR-L1 (FOXO3a. Enhanced SGK1 activity fosters the development of hypertension, obesity, diabetes, thrombosis, stroke, inflammation including inflammatory bowel disease and autoimmune disease, cardiac fibrosis, proteinuria, renal failure as well as tumor growth. The present brief review makes the case that suboptimal fluid intake in the common population may enhance vasopressin and glucocorticoid levels thus up-regulating SGK1 expression and favouring the development of SGK1

  1. The estimation of lung dose from mid-perineum ionization chamber measurements in total body irradiations: A quality control check on dose delivery

    Energy Technology Data Exchange (ETDEWEB)

    Cross, P. [Saint Vincent`s Hospital, Darlinghurst, NSW (Australia)

    1995-11-01

    A series of patients (eleven males and eight females) receiving total body irradiation prior to bone marrow transplantation was monitored during treatment by recording the dose from an ionization chamber placed between the thighs in the mid-perineal region. The treatment was delivered by opposed lateral 6 MV photon beams. The patient was encompassed by the radiation field with the maximum collimator opening at a distance of 3.49 m from the X-ray focus to the patient mid-line. An analysis was made of the measured dose and the calculated percentage average lung dose for each patient in the series to seek a correlation between measured doses and patients` anatomical data so that estimates of delivered lung doses could be made. Whilst a global factor can be applied to measured dose to predict lung dose, it is concluded that perineal dose measurements distal to the region where dose is prescribed (mean lung dose) are sub-optimal for checks on target dose delivery. Entrance and exit dose measurements at the level of dose prescription (in the thorax) are preferable for more accurate predictions and quality control checks. 6 refs., 1 tab., 2 figs.

  2. High Prevalence of Suboptimal Vitamin D Status and Bone Loss in Adult Short Bowel Syndrome Even After Weaning Off Parenteral Nutrition.

    Science.gov (United States)

    Fan, Shengxian; Ni, Xiaodong; Wang, Jian; Zhang, Yongliang; Tao, Shen; Kong, Wencheng; Li, Yousheng; Li, Jieshou

    2017-04-01

    Previous studies have noticed the high incidence of suboptimal vitamin D (VtD) status and bone loss in short bowel syndrome (SBS) with parenteral nutrition (PN) dependence. However, limited data have focused on adult SBS without PN dependence. Therefore, our objective was to investigate the incidence and risk factors of suboptimal VtD status and bone loss in adult SBS even after weaning off PN. We performed a prospective study of 60 adult patients with SBS. Serum 25-hydroxyvitamin D (25-OHD) was measured by radioimmunoassay. Bone mineral density (BMD) was measured using dual-energy x-ray absorptiometry (DEXA). Medical records and various laboratory parameters were collected in all participants. Suboptimal VtD status was identified in all individuals, including 3 (5.0%) with VtD insufficiency and 57 (95.0%) with VtD deficiency. Residual small bowel length (B, 0.072, P = .001) and duration of SBS (B, -0.066, P = .020) were both significantly correlated with suboptimal VtD levels. Overall, only 2 patients presented a normal BMD; osteopenia and osteoporosis were noted in 41 (68.3%) and 17 (28.3%) individuals, respectively. Low 25-OHD concentration was associated with a decreased BMD (B, 0.065, P = .029). There were no other demographic characteristics or clinical examinations associated with suboptimal VtD levels and bone loss. Suboptimal VtD status and bone loss were common in adult SBS even after weaning off PN. Despite routine oral VtD supplementation, most patients did not achieve satisfactory status. This emphasizes the critical importance of routine surveillance of 25-OHD and BMD, as well as consideration of alternative methods of supplementation after weaning off PN.

  3. High T-cell immune activation and immune exhaustion among individuals with suboptimal CD4 recovery after 4 years of antiretroviral therapy in an African cohort

    Directory of Open Access Journals (Sweden)

    Colebunders Robert

    2011-02-01

    Full Text Available Abstract Background Antiretroviral therapy (ART partially corrects immune dysfunction associated with HIV infection. The levels of T-cell immune activation and exhaustion after long-term, suppressive ART and their correlation with CD4 T-cell count reconstitution among ART-treated patients in African cohorts have not been extensively evaluated. Methods T-cell activation (CD38+HLA-DR+ and immune exhaustion (PD-1+ were measured in a prospective cohort of patients initiated on ART; 128 patient samples were evaluated and subcategorized by CD4 reconstitution after long-term suppressive treatment: Suboptimal [median CD4 count increase 129 (-43-199 cells/μl], N = 34 ], optimal [282 (200-415 cells/μl, N = 64] and super-optimal [528 (416-878 cells/μl, N = 30]. Results Both CD4+ and CD8 T-cell activation was significantly higher among suboptimal CD4 T-cell responders compared to super-optimal responders. In a multivariate model, CD4+CD38+HLADR+ T-cells were associated with suboptimal CD4 reconstitution [AOR, 5.7 (95% CI, 1.4-23, P = 0.014]. T-cell exhaustion (CD4+PD1+ and CD8+PD1+ was higher among suboptimal relative to optimal (P P = 0.022]. Conclusion T-cell activation and exhaustion persist among HIV-infected patients despite long-term, sustained HIV-RNA viral suppression. These immune abnormalities were associated with suboptimal CD4 reconstitution and their regulation may modify immune recovery among suboptimal responders to ART.

  4. Rootstock Sub-Optimal Temperature Tolerance Determines Transcriptomic Responses after Long-Term Root Cooling in Rootstocks and Scions of Grafted Tomato Plants.

    Science.gov (United States)

    Ntatsi, Georgia; Savvas, Dimitrios; Papasotiropoulos, Vassilis; Katsileros, Anastasios; Zrenner, Rita M; Hincha, Dirk K; Zuther, Ellen; Schwarz, Dietmar

    2017-01-01

    Grafting of elite cultivars onto tolerant rootstocks is an advanced strategy to increase tomato tolerance to sub-optimal temperature. However, a detailed understanding of adaptive mechanisms to sub-optimal temperature in rootstocks and scions of grafting combinations on a physiological and molecular level is lacking. Here, the commercial cultivar Kommeet was grafted either onto 'Moneymaker' (sensitive) or onto the line accession LA 1777 of Solanum habrochaites (tolerant). Grafted plants were grown in NFT-system at either optimal (25°C) or sub-optimal (15°C) temperatures in the root environment with optimal air temperature (25°C) for 22 days. Grafting onto the differently tolerant rootstocks caused differences in shoot fresh and dry weight, total leaf area and dry matter content of roots, in stomatal conductance and intercellular CO2 and guaiacol peroxidase activity but not in net photosynthesis, sugar, starch and amino acid content, lipid peroxidation and antioxidant enzyme activity. In leaves, comparative transcriptome analysis identified 361 differentially expressed genes (DEG) responding to sub-optimal root temperature when 'Kommeet' was grafted onto the sensitive but no when grafted onto the tolerant rootstock. 1509 and 2036 DEG responding to sub-optimal temperature were identified in LA 1777 and 'Moneymaker' rootstocks, respectively. In tolerant rootstocks down-regulated genes were enriched in main stress-responsive functional categories and up-regulated genes in cellulose synthesis suggesting that cellulose synthesis may be one of the main adaptation mechanisms to long-term sub-optimal temperature. Down-regulated genes of the sensitive rootstock showed a similar response, but functional categories of up-regulated genes pointed to induced stress responses. Rootstocks of the sensitive cultivar Moneymaker showed in addition an enrichment of up-regulated genes in the functional categories fatty acid desaturation, phenylpropanoids, biotic stress, cytochrome P

  5. Rootstock Sub-Optimal Temperature Tolerance Determines Transcriptomic Responses after Long-Term Root Cooling in Rootstocks and Scions of Grafted Tomato Plants

    Directory of Open Access Journals (Sweden)

    Georgia Ntatsi

    2017-06-01

    Full Text Available Grafting of elite cultivars onto tolerant rootstocks is an advanced strategy to increase tomato tolerance to sub-optimal temperature. However, a detailed understanding of adaptive mechanisms to sub-optimal temperature in rootstocks and scions of grafting combinations on a physiological and molecular level is lacking. Here, the commercial cultivar Kommeet was grafted either onto ‘Moneymaker’ (sensitive or onto the line accession LA 1777 of Solanum habrochaites (tolerant. Grafted plants were grown in NFT-system at either optimal (25°C or sub-optimal (15°C temperatures in the root environment with optimal air temperature (25°C for 22 days. Grafting onto the differently tolerant rootstocks caused differences in shoot fresh and dry weight, total leaf area and dry matter content of roots, in stomatal conductance and intercellular CO2 and guaiacol peroxidase activity but not in net photosynthesis, sugar, starch and amino acid content, lipid peroxidation and antioxidant enzyme activity. In leaves, comparative transcriptome analysis identified 361 differentially expressed genes (DEG responding to sub-optimal root temperature when ‘Kommeet’ was grafted onto the sensitive but no when grafted onto the tolerant rootstock. 1509 and 2036 DEG responding to sub-optimal temperature were identified in LA 1777 and ‘Moneymaker’ rootstocks, respectively. In tolerant rootstocks down-regulated genes were enriched in main stress-responsive functional categories and up-regulated genes in cellulose synthesis suggesting that cellulose synthesis may be one of the main adaptation mechanisms to long-term sub-optimal temperature. Down-regulated genes of the sensitive rootstock showed a similar response, but functional categories of up-regulated genes pointed to induced stress responses. Rootstocks of the sensitive cultivar Moneymaker showed in addition an enrichment of up-regulated genes in the functional categories fatty acid desaturation, phenylpropanoids

  6. Obstetric pharmacokinetic dosing studies are urgently needed

    Directory of Open Access Journals (Sweden)

    Shelley A. McCormack

    2014-02-01

    Full Text Available Use of pharmacotherapy during pregnancy is common and increasing. Physiologic changes during pregnancy may significantly alter overall systemic drug exposure, necessitating dose changes. A search of PubMed for pharmacokinetic studies showed 494 publications during pregnancy out of 35,921 total pharmacokinetic published studies (1.29%, from the late 1960s through August 31, 2013. Closer examination of pharmacokinetic studies in pregnant women published since 2008 (81 studies revealed that about a third of the trials were for treatment of acute labor and delivery issues, a third included studies of infectious disease treatment during pregnancy, and the remaining third were for varied antepartum indications. Approximately two-thirds of these recent studies were primarily funded by government agencies worldwide, one quarter were supported by private non-profit foundations or combinations of government and private funding, and slightly less than 10% were supported by pharmaceutical industry. As highlighted in this review, vast gaps exist in pharmacology information and evidence for appropriate dosing of medications in pregnant women. This lack of knowledge and understanding of drug disposition throughout pregnancy place both the mother and the fetus at risk for avoidable therapeutic misadventures – suboptimal efficacy or excess toxicity – with medication use in pregnancy. Increased efforts to perform and support obstetric dosing and pharmacokinetic studies are greatly needed.

  7. Conversion coefficients for determining organ doses in paediatric pelvis and hip joint radiography.

    Science.gov (United States)

    Seidenbusch, Michael C; Schneider, Karl

    2014-09-01

    Knowledge of organ and effective doses achieved during paediatric X-ray examinations is an important prerequisite for assessment of radiation burden to the patient. Conversion coefficients for reconstruction of organ and effective doses from entrance doses for pelvis and hip joint radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients are provided regarding the Guidelines of Good Radiographic Technique of the European Commission. Using the personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Säteilyturvakeskus STUK), conversion coefficients for conventional pelvis and hip joint radiographs were calculated by performing Monte Carlo simulations in mathematical hermaphrodite phantom models representing patients of different ages. The clinical variation of radiation field settings was taken into consideration by defining optimal and suboptimal standard field settings. Conversion coefficients for the reconstruction of organ doses in about 40 organs and tissues from measured entrance doses during pelvis and hip joint radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients were calculated for the standard sagittal beam projection and the standard focus detector distance of 115 cm. The conversion coefficients presented can be used for organ dose assessments from entrance doses measured during pelvis and hip joint radiographs of children and young adults with all field settings within the optimal and suboptimal standard field settings.

  8. Suboptimal enhancer sequences are required for efficient bovine leukemia virus propagation in vivo: implications for viral latency.

    Science.gov (United States)

    Merezak, C; Pierreux, C; Adam, E; Lemaigre, F; Rousseau, G G; Calomme, C; Van Lint, C; Christophe, D; Kerkhofs, P; Burny, A; Kettmann, R; Willems, L

    2001-08-01

    Repression of viral expression is a major strategy developed by retroviruses to escape from the host immune response. The absence of viral proteins (or derived peptides) at the surface of an infected cell does not permit the establishment of an efficient immune attack. Such a strategy appears to have been adopted by animal oncoviruses such as bovine leukemia virus (BLV) and human T-cell leukemia virus (HTLV). In BLV-infected animals, only a small fraction of the infected lymphocytes (between 1 in 5,000 and 1 in 50,000) express large amounts of viral proteins; the vast majority of the proviruses are repressed at the transcriptional level. Induction of BLV transcription involves the interaction of the virus-encoded Tax protein with the CREB/ATF factors; the resulting complex is able to interact with three 21-bp Tax-responsive elements (TxRE) located in the 5' long terminal repeat (5' LTR). These TxRE contain cyclic AMP-responsive elements (CRE), but, remarkably, the "TGACGTCA" consensus is never strictly conserved in any viral strain (e.g.,AGACGTCA, TGACGGCA, TGACCTCA). To assess the role of these suboptimal CREs, we introduced a perfect consensus sequence within the TxRE and showed by gel retardation assays that the binding efficiency of the CREB/ATF proteins was increased. However, trans-activation of a luciferase-based reporter by Tax was not affected in transient transfection assays. Still, in the absence of Tax, the basal promoter activity of the mutated LTR was increased as much as 20-fold. In contrast, mutation of other regulatory elements within the LTR (the E box, NF-kappa B, and glucocorticoid- or interferon-responsive sites [GRE or IRF]) did not induce a similar alteration of the basal transcription levels. To evaluate the biological relevance of these observations made in vitro, the mutations were introduced into an infectious BLV molecular clone. After injection into sheep, it appeared that all the recombinants were infectious in vivo and did not revert

  9. A novel tool to assess available hydrological information and the occurrence of sub-optimal water allocation decisions in large irrigation districts

    NARCIS (Netherlands)

    Kaune, Alexander; Werner, Micha; Rodríguez, Erasmo; Karimi, Poolad; Fraiture, de Charlotte

    2017-01-01

    Hydrological information on water availability and demand is vital for sound water allocation decisions in irrigation districts, particularly in times of water scarcity. However, water allocation decisions are often taken based on uncertain hydrological information, which may lead to sub-optimal

  10. Sensor-augmented pump therapy lowers HbA(1c) in suboptimally controlled Type 1 diabetes; a randomized controlled trial

    NARCIS (Netherlands)

    Hermanides, J.; Nørgaard, K.; Bruttomesso, D.; Mathieu, C.; Frid, A.; Dayan, C. M.; Diem, P.; Fermon, C.; Wentholt, I. M. E.; Hoekstra, J. B. L.; DeVries, J. H.

    2011-01-01

    To investigate the efficacy of sensor-augmented pump therapy vs. multiple daily injection therapy in patients with suboptimally controlled Type 1 diabetes. In this investigator-initiated multi-centre trial (the Eurythmics Trial) in eight outpatient centres in Europe, we randomized 83 patients with

  11. The effect of plant-based diet and suboptimal environmental conditions on digestive function and diet-induced enteropathy in rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Mosberian-Tanha, P.; Schrama, J.W.; Landsverk, T.; Mydland, L.T.; Øverland, M.

    2017-01-01

    This experiment investigated intestinal enteropathy and digestive function of rainbow trout challenged with soybean meal-based diet (SBM) at optimal or suboptimal environments created by normal or reduced water flow, respectively. Oxygen level remained above 7 mg L-1 for optimal environment and

  12. Physician, organizational, and patient factors associated with suboptimal blood pressure mManagement in Type 2 diabetic patients in primary care

    NARCIS (Netherlands)

    Schaars, CF; Denig, P; Kasje, WN; Stewart, RE; Wolffenbuttel, BHR; Haaijer-Ruskamp, FM

    OBJECTIVE - To assess the quality of hypertension care in patients with type 2 diabetes in general practice and identify physician, organizational, and patient factors associated with suboptimal care. RESEARCH DESIGN AND METHODS - Data from 895 randomly selected diabetic patients were extracted from

  13. Effects of feeding frequency on apparent energy and nutrient digestibility/availability of channel catfish, Ictalurus punctatus, reared at optimal and suboptimal temperatures

    Science.gov (United States)

    This study examined the effects of feeding frequency (daily versus every other day [EOD]) on nutrient digestibility/availability of channel catfish, Ictalurus punctatus, reared at optimal (30 C) and suboptimal (24 C) temperatures. A 28% protein practical diet was used as the test diet, and chromic o...

  14. Sub-optimal vitamin B-12 levels among ART-naive HIV-positive individuals in an urban cohort in Uganda.

    Directory of Open Access Journals (Sweden)

    Aggrey S Semeere

    Full Text Available Malnutrition is common among HIV-infected individuals and is often accompanied by low serum levels of micronutrients. Vitamin B-12 deficiency has been associated with various factors including faster HIV disease progression and CD4 depletion in resource-rich settings. To describe prevalence and factors associated with sub-optimal vitamin B-12 levels among HIV-infected antiretroviral therapy (ART naïve adults in a resource-poor setting, we performed a cross-sectional study with a retrospective chart review among individuals attending either the Mulago-Mbarara teaching hospitals' Joint AIDS Program (MJAP or the Infectious Diseases Institute (IDI clinics, in Kampala, Uganda. Logistic regression was used to determine factors associated with sub-optimal vitamin B-12. The mean vitamin B-12 level was 384 pg/ml, normal range (200-900. Sub-optimal vitamin B-12 levels (<300 pg/ml were found in 75/204 (36.8%. Twenty-one of 204 (10.3% had vitamin B-12 deficiency (<200 pg/ml while 54/204 (26.5% had marginal depletion (200-300 pg/ml. Irritable mood was observed more among individuals with sub-optimal vitamin B-12 levels (OR 2.5, 95% CI; 1.1-5.6, P=0.03. Increasing MCV was associated with decreasing serum B-12 category; 86.9 fl (± 5.1 vs. 83 fl (± 8.4 vs. 82 fl (± 8.4 for B-12 deficiency, marginal and normal B-12 categories respectively (test for trend, P=0.017. Compared to normal B-12, individuals with vitamin B-12 deficiency had a longer known duration of HIV infection: 42.2 months (± 27.1 vs. 29.4 months (± 23.8; P=0.02. Participants eligible for ART (CD4<350 cells/µl with sub-optimal B-12 had a higher mean rate of CD4 decline compared to counterparts with normal B-12; 118 (± 145 vs. 22 (± 115 cells/µl/year, P=0.01 respectively. The prevalence of a sub-optimal vitamin B-12 was high in this HIV-infected, ART-naïve adult clinic population in urban Uganda. We recommend prospective studies to further clarify the causal relationships of sub-optimal

  15. Effects of mannan oligosaccharide and virginiamycin on the cecal microbial community and intestinal morphology of chickens raised under suboptimal conditions.

    Science.gov (United States)

    Pourabedin, Mohsen; Xu, Zhengxin; Baurhoo, Bushansingh; Chevaux, Eric; Zhao, Xin

    2014-05-01

    There is an increasing movement against use of antibiotic growth promoters in animal feed. Prebiotic supplementation is a potential alternative to enhance the host's natural defense through modulation of gut microbiota. In the present study, the effect of mannan oligosaccharide (MOS) and virginiamycin (VIRG) on cecal microbial ecology and intestinal morphology of broiler chickens raised under suboptimal conditions was evaluated. MOS and VIRG induced different bacterial community structures, as revealed by denaturing gradient gel electrophoresis of 16S rDNA. The antibiotic treatment reduced cecal microbial diversity while the community equitability increased. A higher bacterial diversity was observed in the cecum of MOS-supplemented birds. Quantitative polymerase chain reaction results indicated that MOS changed the cecal microbiota in favor of the Firmicutes population but not the Bacteroidetes population. No difference was observed in total bacterial counts among treatments. MOS promoted the growth of Lactobacillus spp. and Bifidobacterium spp. in the cecum and increased villus height and goblet cell numbers in the ileum and jejunum. These results provide a deeper insight into the microbial ecological changes after supplementation of MOS prebiotic in poultry diets.

  16. Plasticity of Tiller Dynamics in Wild Rice Oryza rufipogon Griff.: A Strategy for Resilience in Suboptimal Environments

    Directory of Open Access Journals (Sweden)

    Pravat K. Mohapatra

    2011-01-01

    Full Text Available Rice cultivation in tropical Asia is susceptible to drought and flood and the need is high for stress resistant genes. Wild rice Oryza rufipogon Griff., grows in close sympatric association with cultivated rice in various habitats across the globe and possesses traits for survival under challenging environments. The species adapts according to the level of soil moisture available and modifies phenology, biomass production and grain yield. Variation in tiller dynamics of the species between contrasting environments gives an estimate of the adaptation. The species possesses AA genome, which permits genetic compatibility for cross breeding with cultivated rice. Utility of the species as possible repository of stress resistant genes is evaluated in this review by examining variation in assimilate partitioning between different classes of tillers of ecotypes growing across a gradation of habitats against background knowledge available for cultivated rice. Models have been constructed to explain mechanisms of tillering and tiller dynamics, and reveal the genotypic permissibility for resilience in sub-optimal environments. It is concluded that environmentally cued alteration in assimilate production and partitioning mask genetic potential for tiller production and survival. Tiller number in excess of resource capacity is corrected by senescence of late-tillers possibly through an ethylene-mediated signal.

  17. Psychological Distress Mediates the Association between Food Insecurity and Suboptimal Sleep Quality in Latinos with Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Bermúdez-Millán, Angela; Pérez-Escamilla, Rafael; Segura-Pérez, Sofia; Damio, Grace; Chhabra, Jyoti; Osborn, Chandra Y; Wagner, Julie

    2016-10-01

    Evidence increasingly indicates that poor sleep quality is a major public health concern. Household food insecurity (HFI) disproportionately affects Latinos and is a novel risk factor for poor sleep quality. Psychological distress may be a potential mechanism through which HFI affects sleep quality. Sleep, food insecurity, and distress are linked to type 2 diabetes mellitus. We examined the relations between HFI, psychological distress, and sleep quality and tested whether psychological distress mediates the relation between HFI and sleep in people with diabetes mellitus. Latinos with type 2 diabetes mellitus (n = 121) who completed baseline assessments for the CALMS-D (Community Health Workers Assisting Latinos Manage Stress and Diabetes) stress management intervention trial completed the US Household Food Security Survey, and measures of depressive symptoms [Personal Health Questionnaire Depression Scale (PHQ-8)], anxiety symptoms [Patient-Reported Outcomes Measurement Information System (PROMIS)-short], diabetes distress [Problem Areas in Diabetes Questionnaire (PAID-5)], and sleep quality [Pittsburgh Sleep Quality Index (PSQI)]. Psychological distress was operationalized with the PHQ-8, PROMIS-short, and PAID-5 scales. We used unadjusted and adjusted indirect effect tests with bias-corrected bootstrapped 95% CIs on 10,000 samples to test both relations between variables and potential mediation. Mean age was 61 y, 74% were women, and 67% were food insecure. Experiencing HFI was associated with both greater psychological distress and worse sleep quality (P sleep quality with and without adjustment for age, education, income, marital status, and employment status. Household food insecurity is a common and potent household stressor that is associated with suboptimal sleep quality through psychological distress. Efforts to improve food security and decrease psychological distress may yield improved sleep in this high-risk population. The CALMS-D stress management

  18. Effects of TCMC on Transformation of Good Health Status to Suboptimal Health Status: A Nested Case-Control Study

    Directory of Open Access Journals (Sweden)

    Tian Wang

    2015-01-01

    Full Text Available To explore the effects of traditional Chinese medicine constitution (TCMC on transformation of good health status to suboptimal health status (SHS, we conducted a nested case-control study among college students in China. During the 18-month mean follow-up time, 543 cases of SHS (42.7% occurred in 1273 healthy students. There was a significant (P=0.000 and marked reduction in SHMS V1.0 total score in the case group at the 18-month follow-up (69.32 ± 5.45 compared with baseline (78.60 ± 4.70, but there was no significant change in the control group. Conditional logistic regression analysis showed that respondents reporting Yin-deficiency and Qi-deficiency were, respectively, 2.247 and 2.198 times more likely to develop SHS, while tendency to Yin-deficiency and tendency to Damp-heat were, respectively, 1.642 and 1.506 times more likely to develop SHS. However, the Balanced Constitution was a significant protective factor (OR 0.649; P<0.05. Altogether, these findings demonstrate that Yin-deficiency, Qi-deficiency, tendency to Yin-deficiency, and tendency to Damp-heat appeared to induce a change in health status to SHS, while the Balanced Constitution seemed to restrain this change. We conclude that regulating the unbalanced TCMC (such as Yin-deficiency and Qi-deficiency may prevent a healthy status developing into SHS or lead to the regression of SHS.

  19. Educational intervention to reduce disease related to sub-optimal basic hygiene in Rwanda: initial evaluation and feasibility study.

    Science.gov (United States)

    Stone, Margaret A; Ndagijimana, Hormisdas

    2018-01-01

    Despite a global reduction in morbidity related to sub-optimal water, sanitation and hygiene, the incidence of such diseases remains a significant problem in sub-Saharan Africa. This study aimed to initially assess the potential effectiveness (primarily in terms of impact on morbidity) of a simple educational intervention delivered in Rwanda. Additionally, we sought to explore feasibility relating to the practicality of evaluating and implementing this type of intervention in a low- and middle-income country. Two districts in Northern Province were purposively selected; one was randomly allocated to receive the intervention, with the other acting as control. The intervention was based on an interactive DVD about basic hygiene. Baseline and follow-up data for incident cases of relevant morbidities were collected from health centre records. Changes were compared between the two districts using descriptive statistics and chi-squared tests. Qualitative data were obtained through observations, discussions and feedback and were analysed thematically. Cases of infection with intestinal worms and parasites were frequently recorded in both districts. For these morbidities, there was a 39% decrease in cases between baseline and follow-up in the intervention district (4995 reduced to 3069), compared to 13% (5002 reduced to 4356) in the control district (p evaluation and implementation, whilst also highlighting problems encountered and possible solutions, in particular, the potential advantages of training local personnel to deliver this type of intervention. This small-scale study has a number of acknowledged limitations which would need to be addressed in a larger study in order to confidently confirm the effectiveness of the intervention. It nevertheless provides evidence suggesting that the educational intervention is promising in terms of a potential impact on health and feasible to deliver and evaluate. These findings indicate that further evaluation and possibly early

  20. Comparison of dry powder versus nebulized beta-agonist in patients with COPD who have suboptimal peak inspiratory flow rate.

    Science.gov (United States)

    Mahler, Donald A; Waterman, Laurie A; Ward, Joseph; Gifford, Alex H

    2014-04-01

    A peak inspiratory flow rate (PIFR) of powder inhaler (DPI) may limit the ability of a patient with chronic obstructive pulmonary disease (COPD) to achieve bronchodilation. The hypothesis was that lung function would be higher with a beta-agonist inhaled via nebulization compared with dry powder in patients with COPD who exhibit a PIFRresist of powder (50 μg) via Diskus. The primary outcome was the change in lung function from baseline at 2 hr as these two inhaled beta-agonists have the similar peak bronchodilator effect as measured by forced expiratory volume in 1 sec (FEV1). Twenty patients (15 females/5 males) with postalbuterol FEV1 of 0.83±0.31 L (38±12% predicted) and PIFRresist of 53±5 L/min completed the study. At 15 min, improvements in FEV1, forced vital capacity (FVC), and IC were significantly higher with arformoterol than with salmeterol. At 2 hr, changes in FVC and IC, but not FEV1, were significantly higher with arformoterol. At visit 3, patient preference was similar for salmeterol Diskus (n=8) and arformoterol solution (n=7), whereas five patients reported no preference. At peak effect (2 hr), volume responses were greater with arfomoterol via nebulizer compared with dry powder salmeterol in patients with COPD who had a PIFRresist of <60 L/min. Bronchodilator therapy via nebulization should be considered in patients with COPD who have a suboptimal PIFRresist against a particular DPI.

  1. Coadministration of Hedera helix L. Extract Enabled Mice to Overcome Insufficient Protection against Influenza A/PR/8 Virus Infection under Suboptimal Treatment with Oseltamivir.

    Directory of Open Access Journals (Sweden)

    Eun-Hye Hong

    Full Text Available Several anti-influenza drugs that reduce disease manifestation exist, and although these drugs provide clinical benefits in infected patients, their efficacy is limited by the emergence of drug-resistant influenza viruses. In the current study, we assessed the therapeutic strategy of enhancing the antiviral efficacy of an existing neuraminidase inhibitor, oseltamivir, by coadministering with the leaf extract from Hedera helix L, commonly known as ivy. Ivy extract has anti-inflammatory, antibacterial, antifungal, and antihelminthic properties. In the present study, we investigated its potential antiviral properties against influenza A/PR/8 (PR8 virus in a mouse model with suboptimal oseltamivir that mimics a poor clinical response to antiviral drug treatment. Suboptimal oseltamivir resulted in insufficient protection against PR8 infection. Oral administration of ivy extract with suboptimal oseltamivir increased the antiviral activity of oseltamivir. Ivy extract and its compounds, particularly hedrasaponin F, significantly reduced the cytopathic effect in PR8-infected A549 cells in the presence of oseltamivir. Compared with oseltamivir treatment alone, coadministration of the fraction of ivy extract that contained the highest proportion of hedrasaponin F with oseltamivir decreased pulmonary inflammation in PR8-infected mice. Inflammatory cytokines and chemokines, including tumor necrosis factor-alpha and chemokine (C-C motif ligand 2, were reduced by treatment with oseltamivir and the fraction of ivy extract. Analysis of inflammatory cell infiltration in the bronchial alveolar of PR8-infected mice revealed that CD11b+Ly6G+ and CD11b+Ly6Cint cells were recruited after virus infection; coadministration of the ivy extract fraction with oseltamivir reduced infiltration of these inflammatory cells. In a model of suboptimal oseltamivir treatment, coadministration of ivy extract fraction that includes hedrasaponin F increased protection against PR8

  2. Coadministration of Hedera helix L. Extract Enabled Mice to Overcome Insufficient Protection against Influenza A/PR/8 Virus Infection under Suboptimal Treatment with Oseltamivir.

    Science.gov (United States)

    Hong, Eun-Hye; Song, Jae-Hyoung; Shim, Aeri; Lee, Bo-Ra; Kwon, Bo-Eun; Song, Hyuk-Hwan; Kim, Yeon-Jeong; Chang, Sun-Young; Jeong, Hyeon Gun; Kim, Jong Geal; Seo, Sang-Uk; Kim, HyunPyo; Kwon, YongSoo; Ko, Hyun-Jeong

    2015-01-01

    Several anti-influenza drugs that reduce disease manifestation exist, and although these drugs provide clinical benefits in infected patients, their efficacy is limited by the emergence of drug-resistant influenza viruses. In the current study, we assessed the therapeutic strategy of enhancing the antiviral efficacy of an existing neuraminidase inhibitor, oseltamivir, by coadministering with the leaf extract from Hedera helix L, commonly known as ivy. Ivy extract has anti-inflammatory, antibacterial, antifungal, and antihelminthic properties. In the present study, we investigated its potential antiviral properties against influenza A/PR/8 (PR8) virus in a mouse model with suboptimal oseltamivir that mimics a poor clinical response to antiviral drug treatment. Suboptimal oseltamivir resulted in insufficient protection against PR8 infection. Oral administration of ivy extract with suboptimal oseltamivir increased the antiviral activity of oseltamivir. Ivy extract and its compounds, particularly hedrasaponin F, significantly reduced the cytopathic effect in PR8-infected A549 cells in the presence of oseltamivir. Compared with oseltamivir treatment alone, coadministration of the fraction of ivy extract that contained the highest proportion of hedrasaponin F with oseltamivir decreased pulmonary inflammation in PR8-infected mice. Inflammatory cytokines and chemokines, including tumor necrosis factor-alpha and chemokine (C-C motif) ligand 2, were reduced by treatment with oseltamivir and the fraction of ivy extract. Analysis of inflammatory cell infiltration in the bronchial alveolar of PR8-infected mice revealed that CD11b+Ly6G+ and CD11b+Ly6Cint cells were recruited after virus infection; coadministration of the ivy extract fraction with oseltamivir reduced infiltration of these inflammatory cells. In a model of suboptimal oseltamivir treatment, coadministration of ivy extract fraction that includes hedrasaponin F increased protection against PR8 infection that could be

  3. Identifying abnormalities in symbiotic development between Trifolium spp. and Rhizobium leguminosarum bv. trifolii leading to sub-optimal and ineffective nodule phenotypes

    Science.gov (United States)

    Melino, V. J.; Drew, E. A.; Ballard, R. A.; Reeve, W. G.; Thomson, G.; White, R. G.; O'Hara, G. W.

    2012-01-01

    Background and Aims Legumes overcome nitrogen limitations by entering into a mutualistic symbiosis with N2-fixing bacteria (rhizobia). Fully compatible associations (effective) between Trifolium spp. and Rhizobium leguminosarum bv. trifolii result from successful recognition of symbiotic partners in the rhizosphere, root hair infection and the formation of nodules where N2-fixing bacteroids reside. Poorly compatible associations can result in root nodule formation with minimal (sub-optimal) or no (ineffective) N2-fixation. Despite the abundance and persistence of strains in agricultural soils which are poorly compatible with the commercially grown clover species, little is known of how and why they fail symbiotically. The aims of this research were to determine the morphological aberrations occurring in sub-optimal and ineffective clover nodules and to determine whether reduced bacteroid numbers or reduced N2-fixing activity is the main cause for the Sub-optimal phenotype. Methods Symbiotic effectiveness of four Trifolium hosts with each of four R. leguminosarum bv. trifolii strains was assessed by analysis of plant yields and nitrogen content; nodule yields, abundance, morphology and internal structure; and bacteroid cytology, quantity and activity. Key Results Effective nodules (Nodule Function 83–100 %) contained four developmental zones and N2-fixing bacteroids. In contrast, Sub-optimal nodules of the same age (Nodule Function 24–57 %) carried prematurely senescing bacteroids and a small bacteroid pool resulting in reduced shoot N. Ineffective-differentiated nodules carried bacteroids aborted at stage 2 or 3 in differentiation. In contrast, bacteroids were not observed in Ineffective-vegetative nodules despite the presence of bacteria within infection threads. Conclusions Three major responses to N2-fixation incompatibility between Trifolium spp. and R. l. trifolii strains were found: failed bacterial endocytosis from infection threads into plant cortical

  4. Discovery, screening and evaluation of a plasma biomarker panel for subjects with psychological suboptimal health state using 1H-NMR-based metabolomics profiles

    OpenAIRE

    Jun-sheng Tian; Xiao-tao Xia; Yan-fei Wu; Lei Zhao; Huan Xiang; Guan-hua Du; Xiang Zhang; Xue-mei Qin

    2016-01-01

    Individuals in the state of psychological suboptimal health keep increasing, only scales and questionnaires were used to diagnose in clinic under current conditions, and symptoms of high reliability and accuracy are destitute. Therefore, the noninvasive and precise laboratory diagnostic methods are needed. This study aimed to develop an objective method through screen potential biomarkers or a biomarker panel to facilitate the diagnosis in clinic using plasma metabolomics. Profiles were based...

  5. Plasma concentrations of the HIV-protease inhibitor lopinavir are suboptimal in children aged 2 years and below.

    NARCIS (Netherlands)

    Verweel, G.; Burger, D.M.; Sheehan, N.L.; Bergshoeff, A.S.; Warris, A.; Knaap, L.C. van der; Driessen, Gertjan; Groot, R. de; Hartwig, N.G.

    2007-01-01

    BACKGROUND: Lopinavir/ritonavir (LPV/r) has been licensed for the treatment of HIV-infected children >6 months in the US and >2 years in the EU. Limited LPV paediatric pharmacokinetic data are available. We studied LPV pharmacokinetics to determine whether the recommended dose (230/57.5 mg/m2 twice

  6. Maraviroc Intensification of cART in Patients with Suboptimal Immunological Recovery: A 48-Week, Placebo-Controlled Randomized Trial.

    Directory of Open Access Journals (Sweden)

    Steven F L van Lelyveld

    Full Text Available The immunomodulatory effects of the CCR5-antagonist maraviroc might be beneficial in patients with a suboptimal immunological response, but results of different cART (combination antiretroviral therapy intensification studies are conflicting. Therefore, we performed a 48-week placebo-controlled trial to determine the effect of maraviroc intensification on CD4+ T-cell counts and immune activation in these patients.Double-blind, placebo-controlled, randomized trial.Major inclusion criteria were 1. CD4+ T-cell count <350 cells/μL while at least two years on cART or CD4+ T-cell count <200 cells/μL while at least one year on cART, and 2. viral suppression for at least the previous 6 months. HIV-infected patients were randomized to add maraviroc (41 patients or placebo (44 patients to their cART regimen for 48 weeks. Changes in CD4+ T-cell counts (primary endpoint and other immunological parameters were modeled using linear mixed effects models.No significant differences for the modelled increase in CD4+ T-cell count (placebo 15.3 CD4+ T cells/μL (95% confidence interval (CI [1.0, 29.5] versus maraviroc arm 22.9 CD4+ T cells/μL (95% CI [7.4, 38.5] p = 0.51 or alterations in the expression of markers for T-cell activation, proliferation and microbial translocation were found between the arms. However, maraviroc intensification did increase the percentage of CCR5 expressing CD4+ and CD8+ T-cells, and the plasma levels of the CCR5 ligand MIP-1β. In contrast, the percentage of ex-vivo apoptotic CD8+ and CD4+ T-cells decreased in the maraviroc arm.Maraviroc intensification of cART did not increase CD4+ T-cell restoration or decrease immune activation as compared to placebo. However, ex-vivo T-cell apoptosis was decreased in the maraviroc arm.ClinicalTrials.gov NCT00875368.

  7. Initial Accuracy of HIV Rapid Test Kits Stored in Suboptimal Conditions and Validity of Delayed Reading of Oral Fluid Tests.

    Science.gov (United States)

    Choko, Augustine T; Taegtmeyer, Miriam; MacPherson, Peter; Cocker, Derek; Khundi, McEwen; Thindwa, Deus; Sambakunsi, Rodrick S; Kumwenda, Moses K; Chiumya, Kondwani; Malema, Owen; Makombe, Simon D; Webb, Emily L; Corbett, Elizabeth L

    2016-01-01

    To evaluate the effect of storing commonly used rapid diagnostic tests above manufacturer-recommended temperature (at 37°C), and the accuracy of delayed reading of oral fluid kits with relevance to HIV self-testing programmes. A quality assurance study of OraQuick (OraSure), Determine HIV 1/2™ (Alere) and Uni-Gold™ (Recombigen®). Consecutive adults (≥18y) attending Ndirande Health Centre in urban Blantyre, Malawi in January to April 2012 underwent HIV testing with two of each of the three rapid diagnostic test kits stored for 28 days at either 18°C (optimally-stored) or at 37°C (pre-incubated). Used OraQuick test kits were stored in a laboratory for delayed day 1 and subsequent monthly re-reading was undertaken for one year. Of 378 individuals who underwent parallel testing, 5 (1.3%) were dropped from the final analysis due to discordant or missing reference standard results (optimally-stored Determine and Uni-Gold). Compared to the diagnostic reference standard, OraQuick had a sensitivity of 97.2% (95% CI: 93.6-99.6). There were 7 false negative results among all test kits stored at 37°C and three false negatives among optimally stored kits. Excellent agreement between pre-incubated tests and optimally-stored tests with Kappa values of 1.00 for Determine and Uni-Gold; and 0.97 (95% CI: 0.95; 1.00) for OraQuick were observed. There was high visual stability on re-reading of OraQuick, with only 1/375 pre-incubated and 1/371 optimally-stored OraQuick kits changing from the initial result over 12 months. Erroneous results observed during HIV testing in low income settings are likely to be due to factors other than suboptimal storage conditions. Re-reading returned OraQuick kits may offer a convenient and accurate quality assurance approach, including in HIV self-testing programmes.

  8. Work-Recreation Balance, Health-Promoting Lifestyles and Suboptimal Health Status in Southern China: A Cross-Sectional Study.

    Science.gov (United States)

    Wu, Shengwei; Xuan, Zhengzheng; Li, Fei; Xiao, Wei; Fu, Xiuqiong; Jiang, Pingping; Chen, Jieyu; Xiang, Lei; Liu, Yanyan; Nie, Xiaoli; Luo, Ren; Sun, Xiaomin; Kwan, Hiuyee; Zhao, Xiaoshan

    2016-03-19

    Suboptimal health status (SHS)-an intermediate state between health and illness--refers to functional somatic symptoms that are medically undiagnosed. Although- SHS has become a great challenge for global public health, very little about its etiology and mechanisms are known. Work-recreation balance is a part of work-life balance, and is related to stress which greatly influences health status. We therefore carried out a cross-sectional investigation between 2012 and 2013 within a clustered sample of 24,475 individuals aged 15-60 years from a population in southern China. In so doing, we hoped to illuminate the associations between work-recreation balance conditions, healthy lifestyles, and SHS. Work-recreation balance conditions were categorically defined by frequency ("rarely, sometimes, or always"). Health-Promoting Lifestyle Profile (HPLP-II) was used to evaluate the level of healthy lifestyles, and the medical examination report and Sub-Health Measurement Scale V1.0 (SHMS V1.0) were both used to evaluate health status. The ratio of SHS (46.3%) is higher than health status (18.4%) or disease status (35.3%). Overall, 4.9% of respondents reported the lowest level of work-recreation balance, and they scored lower on both the HPLP-II and SHMS V1.0 compared with those who frequently maintained a work-recreation balance. Significant association was found between work-recreation balance behaviors and healthy lifestyles (p work-recreation balance, individuals whose work-recreation balance was categorically "rare" were 1.69 times as likely to develop SHS (odds ratio (OR): 1.69, 95% confidence interval (CI): 1.49-1.92), and those with infrequent work-recreation balance ("sometimes") were 1.71 times more likely to develop SHS (OR: 1.71, 95% CI: 1.62-1.81). These findings suggest that work-recreation balance conditions are significantly associated with, and seem to be accurate behavioral indicia of a healthy lifestyle. Poor work-recreation balance is associated with

  9. Work-Recreation Balance, Health-Promoting Lifestyles and Suboptimal Health Status in Southern China: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Shengwei Wu

    2016-03-01

    Full Text Available Suboptimal health status (SHS—an intermediate state between health and illness—refers to functional somatic symptoms that are medically undiagnosed. Although SHS has become a great challenge for global public health, very little about its etiology and mechanisms are known. Work-recreation balance is a part of work−life balance, and is related to stress which greatly influences health status. We therefore carried out a cross-sectional investigation between 2012 and 2013 within a clustered sample of 24,475 individuals aged 15−60 years from a population in southern China. In so doing, we hoped to illuminate the associations between work-recreation balance conditions, healthy lifestyles, and SHS. Work-recreation balance conditions were categorically defined by frequency (“rarely, sometimes, or always”. Health-Promoting Lifestyle Profile (HPLP-II was used to evaluate the level of healthy lifestyles, and the medical examination report and Sub-Health Measurement Scale V1.0 (SHMS V1.0 were both used to evaluate health status. The ratio of SHS (46.3% is higher than health status (18.4% or disease status (35.3%. Overall, 4.9% of respondents reported the lowest level of work-recreation balance, and they scored lower on both the HPLP-II and SHMS V1.0 compared with those who frequently maintained a work-recreation balance. Significant association was found between work-recreation balance behaviors and healthy lifestyles (p < 0.001 after demographic adjustment. In comparison with those reporting a frequent work-recreation balance, individuals whose work-recreation balance was categorically “rare” were 1.69 times as likely to develop SHS (odds ratio (OR: 1.69, 95% confidence interval (CI: 1.49–1.92, and those with infrequent work-recreation balance (“sometimes” were 1.71 times more likely to develop SHS (OR: 1.71, 95% CI: 1.62–1.81. These findings suggest that work-recreation balance conditions are significantly associated with, and

  10. Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis at calving in dairy herds with suboptimal udder health.

    Science.gov (United States)

    Lundberg, Å; Nyman, A-K; Aspán, A; Börjesson, S; Unnerstad, H Ericsson; Waller, K Persson

    2016-03-01

    Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis are common causes of bovine mastitis. To study these pathogens in early lactation, a 12-mo longitudinal, observational study was carried out in 13 herds with suboptimal udder health. The aims of the study were to investigate the occurrence of these pathogens and to identify if presence of the 3 pathogens, and of genotypes within the pathogens, differed with respect to herd, season, and parity. Quarter milk samples, collected at calving and 4 d in milk (DIM), were cultured for the 3 pathogens. Genotyping of staphylococcal and streptococcal isolates was performed using spa typing and pulsed-field gel electrophoresis, respectively. For each of the 3 pathogens, cows with an udder infection at calving or 4 DIM were allocated to 1 of 4 infection types: cleared (pathogen present only at calving), persistent (pathogen present in the same quarter at calving and 4 DIM), new (pathogen present only at 4 DIM), or cleared/new (pathogen present in 1 quarter at calving and in another quarter at 4 DIM). Associations between season or parity and overall occurrence of pathogens or infection types were determined using univariable mixed-effect logistic-regression models and the Fisher's exact test, respectively. The most commonly occurring pathogen was Staph. aureus, followed by Strep. dysgalactiae and Strep. uberis. Persistent infections were the most common infection type among Staph. aureus-infected cows, whereas cleared infections were the most common among Strep. dysgalactiae- and Strep. uberis-positive cows. The proportion of cows with persistent Staph. aureus infections and the proportion of cows having a Strep. uberis infection at calving or 4 DIM were higher in the multiparous cows than in primiparous cows. Infections with Strep. dysgalactiae were less common during the early housing season than during the late housing or pasture seasons, whereas persistent Strep. uberis

  11. Patients with non-insulin depending diabetes mellitus and metabolic syndrome are suboptimal treated in Swiss primary care.

    Science.gov (United States)

    Schäfer, Hans Hendrik; de Villiers, Jacob Daniel; Lotze, Ulrich; Sivukhina, Elena; Burnier, Michel; Noll, Georg; Theus, Gian-Reto; Dieterle, Thomas

    2013-01-01

    The prevalence of complicated hypertension is increasing in America and Europe. This survey was undertaken to assess the status quo of primary care management of hypertension in patients with the high-risk comorbid diseases metabolic syndrome (MetS) and/or type 2 diabetes mellitus (non-insulin depending diabetes mellitus (NIDDM)). Data of anti-hypertensive treatment of 4594 Swiss patients were collected over 1 week. We identified patients with exclusively NIDDM (N = 95), MetS (N = 168), and both (N = 768). Target blood pressure (TBP) attainment, frequency of prescribed substance-classes, and correlations to comorbidities/end-organ damages were assessed. In addition, we analyzed the prescription of unfavorable beta-blockers (BB) and high-dose diuretics (Ds). In NIDDM, Ds (61%), angiotensin receptor blockers (ARBs) (40%), and angiotensin converting enzyme inhibitors (ACEIs) (31%) were mostly prescribed, while in MetS, drugs prevalence was Ds (68%), ARBs (48%), and BB (41%). Polypharmacy in patients with MetS correlated with body mass index; older patients (>65 years) were more likely to receive dual-free combinations. TBP was attained in 25.2% of NIDDM and in 28.7% of MetS patients. In general, low-dose Ds use was more prevalent in NIDDM and MetS, however, overall, Ds were used excessively (NIDDM: 61%, MetS: 68%), especially in single-pill combination. Patients with MetS were more likely to receive ARBs, ACEIs, CCBs, and low-dose Ds than BBs and/or high-dose Ds. Physicians recognize DM and MetS as high-risk patients, but select inappropriate drugs. Because the majority of patients may have both, MetS and NIDDM, there is an unmet need to define TBP for this specific population considering the increased risk in comparison to patients with MetS or NIDDM alone.

  12. Dose Titration Algorithm Tuning (DTAT should supersede ‘the’ Maximum Tolerated Dose (MTD in oncology dose-finding trials [version 2; referees: 2 approved, 1 approved with reservations

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    David C. Norris

    2017-03-01

    Full Text Available Background. Absent adaptive, individualized dose-finding in early-phase oncology trials, subsequent ‘confirmatory’ Phase III trials risk suboptimal dosing, with resulting loss of statistical power and reduced probability of technical success for the investigational therapy. While progress has been made toward explicitly adaptive dose-finding and quantitative modeling of dose-response relationships, most such work continues to be organized around a concept of ‘the’ maximum tolerated dose (MTD. The purpose of this paper is to demonstrate concretely how the aim of early-phase trials might be conceived, not as ‘dose-finding’, but as dose titration algorithm (DTA-finding. Methods. A Phase I dosing study is simulated, for a notional cytotoxic chemotherapy drug, with neutropenia constituting the critical dose-limiting toxicity. The drug’s population pharmacokinetics and myelosuppression dynamics are simulated using published parameter estimates for docetaxel. The amenability of this model to linearization is explored empirically. The properties of a simple DTA targeting neutrophil nadir of 500 cells/mm 3 using a Newton-Raphson heuristic are explored through simulation in 25 simulated study subjects. Results. Individual-level myelosuppression dynamics in the simulation model approximately linearize under simple transformations of neutrophil concentration and drug dose. The simulated dose titration exhibits largely satisfactory convergence, with great variance in individualized optimal dosing. Some titration courses exhibit overshooting. Conclusions. The large inter-individual variability in simulated optimal dosing underscores the need to replace ‘the’ MTD with an individualized concept of MTDi . To illustrate this principle, the simplest possible DTA capable of realizing such a concept is demonstrated. Qualitative phenomena observed in this demonstration support discussion of the notion of tuning such algorithms. Although here

  13. Dose Titration Algorithm Tuning (DTAT should supersede ‘the’ Maximum Tolerated Dose (MTD in oncology dose-finding trials [version 3; referees: 3 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    David C. Norris

    2017-07-01

    Full Text Available Background. Absent adaptive, individualized dose-finding in early-phase oncology trials, subsequent ‘confirmatory’ Phase III trials risk suboptimal dosing, with resulting loss of statistical power and reduced probability of technical success for the investigational therapy. While progress has been made toward explicitly adaptive dose-finding and quantitative modeling of dose-response relationships, most such work continues to be organized around a concept of ‘the’ maximum tolerated dose (MTD. The purpose of this paper is to demonstrate concretely how the aim of early-phase trials might be conceived, not as ‘dose-finding’, but as dose titration algorithm (DTA-finding. Methods. A Phase I dosing study is simulated, for a notional cytotoxic chemotherapy drug, with neutropenia constituting the critical dose-limiting toxicity. The drug’s population pharmacokinetics and myelosuppression dynamics are simulated using published parameter estimates for docetaxel. The amenability of this model to linearization is explored empirically. The properties of a simple DTA targeting neutrophil nadir of 500 cells/mm 3 using a Newton-Raphson heuristic are explored through simulation in 25 simulated study subjects. Results. Individual-level myelosuppression dynamics in the simulation model approximately linearize under simple transformations of neutrophil concentration and drug dose. The simulated dose titration exhibits largely satisfactory convergence, with great variance in individualized optimal dosing. Some titration courses exhibit overshooting. Conclusions. The large inter-individual variability in simulated optimal dosing underscores the need to replace ‘the’ MTD with an individualized concept of MTDi . To illustrate this principle, the simplest possible DTA capable of realizing such a concept is demonstrated. Qualitative phenomena observed in this demonstration support discussion of the notion of tuning such algorithms. Although here

  14. Prematriculation variables associated with suboptimal outcomes for the 1994-1999 cohort of US medical school matriculants.

    Science.gov (United States)

    Andriole, Dorothy A; Jeffe, Donna B

    2010-09-15

    The relationship between increasing numbers and diversity of medical school enrollees and the US physician workforce size and composition has not been described. To identify demographic and prematriculation factors associated with medical school matriculants' outcomes. Retrospective study using deidentified data for the 1994-1999 national cohort of 97,445 matriculants who were followed up through March 2, 2009, and had graduated, had withdrawn, or were dismissed. Data were analyzed using multivariable logistic regression to identify factors associated with suboptimal outcomes. Academic withdrawal or dismissal, nonacademic withdrawal or dismissal, and graduation without first-attempt passing scores on the US Medical Licensing Examination Step 1 and/or Step 2 Clinical Knowledge (CK) compared with graduation with first-attempt passing scores on both of the examinations. Of 84,018 matriculants (86.2%), 74,494 graduated and had first-attempt passing scores on both the Step 1 and Step 2 CK (88.7%), 6743 graduated and did not have first-attempt passing scores on the Step 1 and/or Step 2 CK (8.0%), 1049 withdrew or were dismissed for academic reasons (1.2%), and 1732 withdrew or were dismissed for nonacademic reasons (2.1%). Variables associated with greater likelihood of graduation without first-attempt passing scores on the Step 1 and/or Step 2 CK and of academic withdrawal or dismissal, respectively, were (1) Medical College Admission Test scores (scores of 18-20 [2.9% of sample] vs > 29: adjusted odds ratio [AOR], 13.06 [95% confidence interval {CI}, 11.56-14.76] and AOR, 11.08 [95% CI, 8.50-14.45]; scores of 21-23 [5.6% of sample] vs > 29: AOR, 7.52 [95% CI, 6.79-8.33] and AOR, 5.97 [95% CI, 4.68-7.62]; and scores of 24-26 [13.9% of sample] vs > 29: AOR, 4.27 [95% CI, 3.92-4.65] and AOR, 3.56 [95% CI, 2.88-4.40]), (2) race/ethnicity (Asian or Pacific Islander [18.2% of sample] vs white: AOR, 2.15 [95% CI, 2.00-2.32] and AOR, 1.69 [95% CI, 1.37-2.09]; underrepresented

  15. How common and what are the determinants of sub-optimal care for Parkinson's disease patients: the Milton Keynes community study.

    Science.gov (United States)

    Hu, Michele T M; Butterworth, Richard; Kumar, Vasantha; Cooper, Jonathan; Jones, Emma; Catterall, Lesley; Ben-Shlomo, Yoav

    2011-03-01

    Limited data currently exists within the UK addressing the level of Parkinson's disease (PD) healthcare provision. We investigated whether care for PD patients in a UK community met national guidelines, and the determinants of sub-optimal care for this patient group. 340 PD patients were identified from a population of 242,606 (crude prevalence 140 per 100,000 (95% CI 126-156 per 100,000), age-adjusted prevalence 199 per 100,000 (95% CI 178-221 per 100,000)). 248 out of 340 (73%) PD patients identified took part, completing rating scales assessing cognitive, non-motor and sociodemographic variables. 9% of patients had never seen a neurologist for their PD and 18.5% were sub-optimally managed; defined as (a) delay between initial diagnosis and first consultation by a specialist >1 year and (b) patients who had not had specialist PD review for >1 year. Older age, poor cognition and worse mobility were major factors in determining sub-optimal care whilst lower education level and tremor as initial symptom were more modest predictors. 20% of patients had been started on dopaminergic therapies including ergot-derived agonists by their GP prior to referral and less than a third had seen allied health professionals throughout their illness. Further work is required to test whether these findings are generalizable across the country and identify what can be done to ensure equal access to specialist care so that all PD patients have access to best practice. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Global convergence analysis of fast multiobjective gradient-based dose optimization algorithms for high-dose-rate brachytherapy.

    Science.gov (United States)

    Lahanas, M; Baltas, D; Giannouli, S

    2003-03-07

    We consider the problem of the global convergence of gradient-based optimization algorithms for interstitial high-dose-rate (HDR) brachytherapy dose optimization using variance-based objectives. Possible local minima could lead to only sub-optimal solutions. We perform a configuration space analysis using a representative set of the entire non-dominated solution space. A set of three prostate implants is used in this study. We compare the results obtained by conjugate gradient algorithms, two variable metric algorithms and fast-simulated annealing. For the variable metric algorithm BFGS from numerical recipes, large fluctuations are observed. The limited memory L-BFGS algorithm and the conjugate gradient algorithm FRPR are globally convergent. Local minima or degenerate states are not observed. We study the possibility of obtaining a representative set of non-dominated solutions using optimal solution rearrangement and a warm start mechanism. For the surface and volume dose variance and their derivatives, a method is proposed which significantly reduces the number of required operations. The optimization time, ignoring a preprocessing step, is independent of the number of sampling points in the planning target volume. Multiobjective dose optimization in HDR brachytherapy using L-BFGS and a new modified computation method for the objectives and derivatives has been accelerated, depending on the number of sampling points, by a factor in the range 10-100.

  17. Missed doses of oral antihyperglycemic medications in US adults with type 2 diabetes mellitus: prevalence and self-reported reasons.

    Science.gov (United States)

    Vietri, Jeffrey T; Wlodarczyk, Catherine S; Lorenzo, Rose; Rajpathak, Swapnil

    2016-09-01

    Adherence to antihyperglycemic medication is thought to be suboptimal, but the proportion of patients missing doses, the number of doses missed, and reasons for missing are not well described. This survey was conducted to estimate the prevalence of and reasons for missed doses of oral antihyperglycemic medications among US adults with type 2 diabetes mellitus, and to explore associations between missed doses and health outcomes. The study was a cross-sectional patient survey. Respondents were contacted via a commercial survey panel and completed an on-line questionnaire via the Internet. Respondents provided information about their use of oral antihyperglycemic medications including doses missed in the prior 4 weeks, personal characteristics, and health outcomes. Weights were calculated to project the prevalence to the US adult population with type 2 diabetes mellitus. Outcomes were compared according to number of doses missed in the past 4 weeks using bivariate statistics and generalized linear models. Approximately 30% of adult patients with type 2 diabetes mellitus reported missing or reducing ≥1 dose of oral antihyperglycemic medication in the prior 4 weeks. Accidental missing was more commonly reported than purposeful skipping, with forgetting the most commonly reported reason. The timing of missed doses suggested respondents had also forgotten about doses missed, so the prevalence of missed doses is likely higher than reported. Outcomes were poorer among those who reported missing three or more doses in the prior 4 weeks. A substantial number of US adults with type 2 diabetes mellitus miss doses of their oral antihyperglycemic medications.

  18. A novel adaptive needle insertion sequencing for robotic, single needle MR-guided high-dose-rate prostate brachytherapy

    Science.gov (United States)

    Borot de Battisti, M.; de Senneville, B. Denis; Hautvast, G.; Binnekamp, D.; Lagendijk, J. J. W.; Maenhout, M.; Moerland, M. A.

    2017-05-01

    MR-guided high-dose-rate (HDR) brachytherapy has gained increasing interest as a treatment for patients with localized prostate cancer because of the superior value of MRI for tumor and surrounding tissues localization. To enable needle insertion into the prostate with the patient in the MR bore, a single needle MR-compatible robotic system involving needle-by-needle dose delivery has been developed at our institution. Throughout the intervention, dose delivery may be impaired by: (1) sub-optimal needle positioning caused by e.g. needle bending, (2) intra-operative internal organ motion such as prostate rotations or swelling, or intra-procedural rectum or bladder filling. This may result in failure to reach clinical constraints. To assess the first aforementioned challenge, a recent study from our research group demonstrated that the deposited dose may be greatly improved by real-time adaptive planning with feedback on the actual needle positioning. However, the needle insertion sequence is left to the doctor and therefore, this may result in sub-optimal dose delivery. In this manuscript, a new method is proposed to determine and update automatically the needle insertion sequence. This strategy is based on the determination of the most sensitive needle track. The sensitivity of a needle track is defined as its impact on the dose distribution in case of sub-optimal positioning. A stochastic criterion is thus presented to determine each needle track sensitivity based on needle insertion simulations. To assess the proposed sequencing strategy, HDR prostate brachytherapy was simulated on 11 patients with varying number of needle insertions. Sub-optimal needle positioning was simulated at each insertion (modeled by typical random angulation errors). In 91% of the scenarios, the dose distribution improved when the needle was inserted into the most compared to the least sensitive needle track. The computation time for sequencing was less than 6 s per needle track. The

  19. An environmental dose experiment

    Science.gov (United States)

    Peralta, Luis

    2017-11-01

    Several radiation sources worldwide contribute to the delivered dose to the human population. This radiation also acts as a natural background when detecting radiation, for instance from radioactive sources. In this work a medium-sized plastic scintillation detector is used to evaluate the dose delivered by natural radiation sources. Calibration of the detector involved the use of radioactive sources and Monte Carlo simulation of the energy deposition per disintegration. A measurement of the annual dose due to background radiation to the body was then estimated. A dose value compatible with the value reported by the United Nations Scientific Committee on the Effects of Atomic Radiation was obtained.

  20. Potent, transient inhibition of BCR-ABL with dasatinib 100 mg daily achieves rapid and durable cytogenetic responses and high transformation-free survival rates in chronic phase chronic myeloid leukemia patients with resistance, suboptimal response or intolerance to imatinib

    Science.gov (United States)

    Shah, Neil P.; Kim, Dong-Wook; Kantarjian, Hagop; Rousselot, Philippe; Llacer, Pedro Enrique Dorlhiac; Enrico, Alicia; Vela-Ojeda, Jorge; Silver, Richard T.; Khoury, Hanna Jean; Müller, Martin C.; Lambert, Alexandre; Matloub, Yousif; Hochhaus, Andreas

    2010-01-01

    Background Dasatinib 100 mg once daily achieves intermittent BCR-ABL kinase inhibition and is approved for chronic-phase chronic myeloid leukemia patients resistant or intolerant to imatinib. To better assess durability of response to and tolerability of dasatinib, data from a 2-year minimum follow-up for a dose-optimization study in chronic-phase chronic myeloid leukemia are reported here. Design and Methods In a phase 3 study, 670 chronic-phase chronic myeloid leukemia patients with resistance, intolerance, or suboptimal response to imatinib were randomized to dasatinib 100 mg once-daily, 50 mg twice-daily, 140 mg once-daily, or 70 mg twice-daily. Results Data from a 2-year minimum follow-up demonstrate that dasatinib 100 mg once daily achieves major cytogenetic response and complete cytogenetic response rates comparable to those in the other treatment arms, and reduces the frequency of key side effects. Comparable 2-year progression-free survival and overall survival rates were observed (80% and 91%, respectively, for 100 mg once daily, and 75%–76% and 88%–94%, respectively, in other arms). Complete cytogenetic responses were achieved rapidly, typically by 6 months. In patients treated with dasatinib 100 mg once daily for 6 months without complete cytogenetic response, the likelihood of achieving such a response by 2 years was 50% for patients who had achieved a partial cytogenetic response, and only 8% or less for patients with minor, minimal, or no cytogenetic response. Less than 3% of patients suffered disease transformation to accelerated or blast phase. Conclusions Intermittent kinase inhibition can achieve rapid and durable responses, indistinguishable from those achieved with more continuous inhibition. PMID:20139391

  1. Supplementation with macular carotenoids reduces psychological stress, serum cortisol, and sub-optimal symptoms of physical and emotional health in young adults.

    Science.gov (United States)

    Stringham, Nicole Tressa; Holmes, Philip V; Stringham, James M

    2017-02-15

    Oxidative stress and systemic inflammation are the root cause of several deleterious effects of chronic psychological stress. We hypothesize that the antioxidant and anti-inflammatory capabilities of the macular carotenoids (MCs) lutein, zeaxanthin, and meso-zeaxanthin could, via daily supplementation, provide a dietary means of benefit. A total of 59 young healthy subjects participated in a 12-month, double-blind, placebo-controlled trial to evaluate the effects of MC supplementation on blood cortisol, psychological stress ratings, behavioural measures of mood, and symptoms of sub-optimal health. Subjects were randomly assigned to one of three groups: placebo, 13 mg, or 27 mg / day total MCs. All parameters were assessed at baseline, 6 months, and 12 months. Serum MCs were determined via HPLC, serum cortisol via ELISA, and macular pigment optical density (MPOD) via customized heterochromatic flicker photometry. Behavioural data were obtained via questionnaire. Significant baseline correlations were found between MPOD and Beck anxiety scores (r = -0.28; P = 0.032), MPOD and Brief Symptom Inventory scores (r = 0.27; P = 0.037), and serum cortisol and psychological stress scores (r = 0.46; P stress, serum cortisol, and measures of emotional and physical health (P stress, cortisol, and symptoms of sub-optimal emotional and physical health. Determining the basis for these effects, whether systemic or a more central (i.e. brain) is a question that warrants further study.

  2. Discovery, screening and evaluation of a plasma biomarker panel for subjects with psychological suboptimal health state using (1)H-NMR-based metabolomics profiles.

    Science.gov (United States)

    Tian, Jun-Sheng; Xia, Xiao-Tao; Wu, Yan-Fei; Zhao, Lei; Xiang, Huan; Du, Guan-Hua; Zhang, Xiang; Qin, Xue-Mei

    2016-09-21

    Individuals in the state of psychological suboptimal health keep increasing, only scales and questionnaires were used to diagnose in clinic under current conditions, and symptoms of high reliability and accuracy are destitute. Therefore, the noninvasive and precise laboratory diagnostic methods are needed. This study aimed to develop an objective method through screen potential biomarkers or a biomarker panel to facilitate the diagnosis in clinic using plasma metabolomics. Profiles were based on H-nuclear magnetic resonance ((1)H-NMR) metabolomics techniques combing with multivariate statistical analysis. Furthermore, methods of correlation analysis with Metaboanalyst 3.0 for selecting a biomarker panel, traditional Chinese medicine (TCM) drug intervention for validating the close relations between the biomarker panel and the state and the receiver operating characteristic curves (ROC curves) analysis for evaluation of clinical diagnosis ability were carried out. 9 endogenous metabolites containing trimethylamine oxide (TMAO), glutamine, N-acetyl-glycoproteins, citrate, tyrosine, phenylalanine, isoleucine, valine and glucose were identified and considered as potential biomarkers. Then a biomarker panel consisting of phenylalanine, glutamine, tyrosine, citrate, N-acetyl-glycoproteins and TMAO was selected, which exhibited the highest area under the curve (AUC = 0.971). This study provided critical insight into the pathological mechanism of psychological suboptimal health and would supply a novel and valuable diagnostic method.

  3. Suboptimal vitamin D status in a population-based study of Asian children: prevalence and relation to allergic diseases and atopy.

    Directory of Open Access Journals (Sweden)

    Tsung-Chieh Yao

    Full Text Available BACKGROUND: New evidence shows high prevalence of vitamin D deficiency in many countries and some studies suggest a possible link between vitamin D status and allergic diseases. The objectives of this study were to determine the prevalence of suboptimal vitamin D status in a population sample of Asian children and to investigate the relationship of vitamin D status with allergic diseases and atopy. METHODS: Children aged 5-18 years (N = 1315 in the Prediction of Allergies in Taiwanese CHildren (PATCH study were evaluated using questionnaires, anthropometric measurements, and serum levels of 25-hydroxyvitamin D [25(OHD] and total and specific immunoglobulin E (IgE. RESULTS: The mean concentration of serum 25(OHD was 20.4 ng/mL (SD: 7.1 ng/mL. Vitamin D deficiency (defined as serum 25(OHD0.05. CONCLUSIONS: Low serum 25(OHD levels are remarkably common in this population sample of Asian children, suggesting that millions of children living in Taiwan may have suboptimal levels of vitamin D, which should be a matter of public health concern. Our results provides epidemiological evidence against the association of vitamin D status with various allergic diseases and atopy in Asian children.

  4. Sub-optimal delivery of intermittent preventive treatment for malaria in pregnancy in Nigeria: influence of provider factors

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    Onoka Chima A

    2012-09-01

    Full Text Available Abstract Background The level of access to intermittent preventive treatment for malaria in pregnancy (IPTp in Nigeria is still low despite relatively high antenatal care coverage in the study area. This paper presents information on provider factors that affect the delivery of IPTp in Nigeria. Methods Data were collected from heads of maternal health units of 28 public and six private health facilities offering antenatal care (ANC services in two districts in Enugu State, south-east Nigeria. Provider knowledge of guidelines for IPTp was assessed with regard to four components: the drug used for IPTp, time of first dose administration, of second dose administration, and the strategy for sulphadoxine-pyrimethamine (SP administration (directly observed treatment, DOT. Provider practices regarding IPTp and facility-related factors that may explain observations such as availability of SP and water were also examined. Results Only five (14.7% of all 34 providers had correct knowledge of all four recommendations for provision of IPTp. None of them was a private provider. DOT strategy was practiced in only one and six private and public providers respectively. Overall, 22 providers supplied women with SP in the facility and women were allowed to take it at home. The most common reason for doing so amongst public providers was that women were required to come for antenatal care on empty stomachs to enhance the validity of manual fundal height estimation. Two private providers did not think it was necessary to use the DOT strategy because they assumed that women would take their drugs at home. Availability of SP and water in the facility, and concerns about side effects were not considered impediments to delivery of IPTp. Conclusion There was low level of knowledge of the guidelines for implementation of IPTp by all providers, especially those in the private sector. This had negative effects such as non-practice of DOT strategy by most of the providers

  5. Fertilizer micro-dosing

    International Development Research Centre (IDRC) Digital Library (Canada)

    millet, sorghum) under micro-dosing and water harvesting. • Farmers' access to fertilizer has been improved by an innovative 'warrantage' credit scheme, that has enabled over 1,000 farmers (30% women), to purchase and use more fertilizer on food crops. Fertilizer micro-dosing: a profitable innovation for. Sahelian women.

  6. Clozapine dose for schizophrenia.

    Science.gov (United States)

    Subramanian, Selvizhi; Völlm, Birgit A; Huband, Nick

    2017-06-14

    Schizophrenia and related disorders such as schizophreniform and schizoaffective disorder are serious mental illnesses characterised by profound disruptions in thinking and speech, emotional processes, behaviour and sense of self. Clozapine is useful in the treatment of schizophrenia and related disorders, particularly when other antipsychotic medications have failed. It improves positive symptoms (such as delusions and hallucinations) and negative symptoms (such as withdrawal and poverty of speech). However, it is unclear what dose of clozapine is most effective with the least side effects. To compare the efficacy and tolerability of clozapine at different doses and to identify the optimal dose of clozapine in the treatment of schizophrenia, schizophreniform and schizoaffective disorders. We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials (August 2011 and 8 December 2016). All relevant randomised controlled trials (RCTs), irrespective of blinding status or language, that compared the effects of clozapine at different doses in people with schizophrenia and related disorders, diagnosed by any criteria. We independently inspected citations from the searches, identified relevant abstracts, obtained full articles of relevant abstracts, and classified trials as included or excluded. We included trials that met our inclusion criteria and reported useable data. For dichotomous data, we calculated the relative risk (RR) and the 95% confidence interval (CI) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD) again based on a random-effects model. We assessed risk of bias for included studies and created 'Summary of findings' tables using GRADE. We identified five studies that could be included. Each compared the effects of clozapine at very low dose (up to 149 mg/day), low dose (150 mg/day to 300 mg/day) and standard dose (301 mg/day to 600 mg/day). Four of the five included

  7. Controllable dose; Dosis controlable

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Anaya M, R.A. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: jtar@nuclear.inin.mx

    2004-07-01

    With the purpose of eliminating the controversy about the lineal hypothesis without threshold which found the systems of dose limitation of the recommendations of ICRP 26 and 60, at the end of last decade R. Clarke president of the ICRP proposed the concept of Controllable Dose: as the dose or dose sum that an individual receives from a particular source which can be reasonably controllable by means of any means; said concept proposes a change in the philosophy of the radiological protection of its concern by social approaches to an individual focus. In this work a panorama of the foundations is presented, convenient and inconveniences that this proposal has loosened in the international community of the radiological protection, with the purpose of to familiarize to our Mexican community in radiological protection with these new concepts. (Author)

  8. Acetaminophen dosing for children

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000783.htm Acetaminophen dosing for children To use the sharing features ... much of this medicine can be harmful. How Acetaminophen Can Help Your Child Acetaminophen is used to ...

  9. Routine use of microarray-based gene expression profiling to identify patients with low cytogenetic risk acute myeloid leukemia: accurate results can be obtained even with suboptimal samples

    Directory of Open Access Journals (Sweden)

    de la Blétière Diane Raingeard

    2012-01-01

    Full Text Available Abstract Background Gene expression profiling has shown its ability to identify with high accuracy low cytogenetic risk acute myeloid leukemia such as acute promyelocytic leukemia and leukemias with t(8;21 or inv(16. The aim of this gene expression profiling study was to evaluate to what extent suboptimal samples with low leukemic blast load (range, 2-59% and/or poor quality control criteria could also be correctly identified. Methods Specific signatures were first defined so that all 71 acute promyelocytic leukemia, leukemia with t(8;21 or inv(16-AML as well as cytogenetically normal acute myeloid leukemia samples with at least 60% blasts and good quality control criteria were correctly classified (training set. The classifiers were then evaluated for their ability to assign to the expected class 111 samples considered as suboptimal because of a low leukemic blast load (n = 101 and/or poor quality control criteria (n = 10 (test set. Results With 10-marker classifiers, all training set samples as well as 97 of the 101 test samples with a low blast load, and all 10 samples with poor quality control criteria were correctly classified. Regarding test set samples, the overall error rate of the class prediction was below 4 percent, even though the leukemic blast load was as low as 2%. Sensitivity, specificity, negative and positive predictive values of the class assignments ranged from 91% to 100%. Of note, for acute promyelocytic leukemia and leukemias with t(8;21 or inv(16, the confidence level of the class assignment was influenced by the leukemic blast load. Conclusion Gene expression profiling and a supervised method requiring 10-marker classifiers enable the identification of favorable cytogenetic risk acute myeloid leukemia even when samples contain low leukemic blast loads or display poor quality control criterion.

  10. Burden of Disease Attributable to Suboptimal Breastfeeding in Iran during 1990-2010; Findings from the Global Burden of Disease Study 2010

    Directory of Open Access Journals (Sweden)

    Roya Kelishadi

    2016-09-01

    Full Text Available Background: This study uses data of the global burden of diseases (GBD study 2010 to report death, disability-adjusted life year (DALYs, years of life lived with disability (YLDs and years of life lost due to premature mortality (YLLs, attributed to suboptimal breastfeeding by age and gender during 1990 to 2010 in Iran. Materials and Methods:The GBD assessments were used, together with estimates of death and DALYs due to specific risk factors to calculate the attributed burden of each risk factor exposure compared with the theoretical-minimum-risk exposure. Uncertainties in the distribution of exposure, relative risks, and relevant outcomes were incorporated into estimates of mortality attributable and burden and were presented as 95 % uncertainty interval (UI. Results:In both genders, the age standardized DALYs rates and the age standardized death rate [(from 5 (95% UI: 2-8 to 1 (95% UI: 0-2 per 100,000 populations], attributed to breastfeeding, had a decreasing trends. The age standardized YLD rate increased from 7 (95% UI: 2-15 to 10 (95% UI: 3-23 per 100,000 populations in boys and, from 7(95% UI: 2-16 to 11(95% UI: 3-26 per 100,000 populations in girls. The YLD changes showed some variation according to age categories. For both genders, the age standardizes YLL rate decreased from 395 (95% UI: 185-681 per 100,000 populations to 111(95% UI: 42-213 per 100,000 populations. Conclusion: The burden attributed to suboptimal breastfeeding had a considerable reduction rate from 1990 to 2010. Additional studies on burden of exclusive breastfeeding with more accurate data are recommended for policies make decision.

  11. Clinical and hemodynamic improvements after adding ambrisentan to background PDE5i therapy in patients with pulmonary arterial hypertension exhibiting a suboptimal therapeutic response (ATHENA-1).

    Science.gov (United States)

    Shapiro, Shelley; Torres, Fernando; Feldman, Jeremy; Keogh, Anne; Allard, Martine; Blair, Christiana; Gillies, Hunter; Tislow, James; Oudiz, Ronald J

    2017-05-01

    Pulmonary arterial hypertension (PAH) is a condition which may lead to right ventricular failure and premature death. While recent data supports the initial combination of ambrisentan (a selective ERA) and tadalafil (a PDE5i) in functional class II or III patients, there is no published data describing the safety and efficacy of ambrisentan when added to patients currently receiving a PDE5i and exhibiting a suboptimal response. The ATHENA-1 study describes the safety and efficacy of the addition of ambrisentan in this patient population. PAH patients with a suboptimal response to current PDE5i monotherapy were assigned ambrisentan in an open-label fashion and evaluated for up to 48 weeks. Cardiopulmonary hemodynamics (change in PVR as primary endpoint) were evaluated at week 24 and functional parameters and biomarkers were measured through week 48. Time to clinical worsening (TTCW) and survival are also described. Thirty-three subjects were included in the analysis. At week 24, statistically significant improvements in PVR (-32%), mPAP (-11%), and CI (+25%) were observed. Hemodynamic improvements at week 24 were further supported by improvements in the secondary endpoints: 6-min walk distance (+18 m), NT-proBNP (-31%), and maintenance or improvement in WHO FC in 97% of patients. Adverse events were consistent with known effects of ambrisentan. The hemodynamic, functional, and biomarker improvements observed in the ATHENA-1 study suggests that the sequential addition of ambrisentan to patients not having a satisfactory response to established PDE5i monotherapy is a reasonable option. Published by Elsevier Ltd.

  12. Utirik Atoll Dose Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Bogen, K.T

    1999-10-06

    On March 1, 1954, radioactive fallout from the nuclear test at Bikini Atoll code-named BRAVO was deposited on Utirik Atoll which lies about 187 km (300 miles) east of Bikini Atoll. The residents of Utirik were evacuated three days after the fallout started and returned to their atoll in May 1954. In this report we provide a final dose assessment for current conditions at the atoll based on extensive data generated from samples collected in 1993 and 1994. The estimated population average maximum annual effective dose using a diet including imported foods is 0.037 mSv y{sup -1} (3.7 mrem y{sup -1}). The 95% confidence limits are within a factor of three of their population average value. The population average integrated effective dose over 30-, 50-, and 70-y is 0.84 mSv (84, mrem), 1.2 mSv (120 mrem), and 1.4 mSv (140 mrem), respectively. The 95% confidence limits on the population-average value post 1998, i.e., the 30-, 50-, and 70-y integral doses, are within a factor of two of the mean value and are independent of time, t, for t > 5 y. Cesium-137 ({sup 137}Cs) is the radionuclide that contributes most of this dose, mostly through the terrestrial food chain and secondarily from external gamma exposure. The dose from weapons-related radionuclides is very low and of no consequence to the health of the population. The annual background doses in the U. S. and Europe are 3.0 mSv (300 mrem), and 2.4 mSv (240 mrem), respectively. The annual background dose in the Marshall Islands is estimated to be 1.4 mSv (140 mrem). The total estimated combined Marshall Islands background dose plus the weapons-related dose is about 1.5 mSv y{sup -1} (150 mrem y{sup -1}) which can be directly compared to the annual background effective dose of 3.0 mSv y{sup -1} (300 mrem y{sup -1}) for the U. S. and 2.4 mSv y{sup -1} (240 mrem y{sup -1}) for Europe. Moreover, the doses listed in this report are based only on the radiological decay of {sup 137}Cs (30.1 y half-life) and other

  13. Argatroban dosing in obesity.

    Science.gov (United States)

    Elagizi, Stephanie; Davis, Kyle

    2018-01-09

    Obesity is associated with significant alterations in pharmacokinetic and pharmacodynamic properties. The use of weight based anticoagulants such as argatroban may put obese patients at an increased risk of hemorrhagic events. The purpose of this study was to evaluate argatroban dosing requirements in obese vs non-obese patients. This single-center, retrospective cohort study included patients ≥18 years with suspected HIT, treated with argatroban for ≥12 h. Patients were stratified by body mass index (BMI) into obese (BMI > 30 kg/m2) and non-obese (BMI ≤ 30 kg/m2) groups. The primary outcome was the median maintenance dose required to achieve two consecutive therapeutic activated partial thromboplastin times. A total of 121 patients were included. The median BMI in the obese vs non-obese groups was 35.8 vs 24.05 kg/m2 (p < .0001). Although statistically significant, there was no clinically significant difference in median maintenance argatroban dose in obese versus non-obese patients (1 vs 1 μg/kg/min; p = .01). In-hospital major bleeding and in-hospital thrombosis also did not differ between the two groups. Obese patients require similar median argatroban maintenance doses when compared to non-obese patients. Based on these results argatroban should be dosed using actual body weight regardless of BMI. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Assessment of internal doses

    CERN Document Server

    Rahola, T; Falk, R; Isaksson, M; Skuterud, L

    2002-01-01

    There is a definite need for training in dose calculation. Our first course was successful and was followed by a second, both courses were fully booked. An example of new tools for software products for bioassay analysis and internal dose assessment is the Integrated Modules for Bioassay Analysis (IMBA) were demonstrated at the second course. This suite of quality assured code modules have been adopted in the UK as the standard for regulatory assessment purposes. The intercomparison measurements are an important part of the Quality Assurance work. In what is known as the sup O utside workers ' directive it is stated that the internal dose measurements shall be included in the European Unions supervision system for radiation protection. The emergency preparedness regarding internal contamination was much improved by the training with and calibration of handheld instruments from participants' laboratories. More improvement will be gained with the handbook giving practical instructions on what to do in case of e...

  15. Radiation dose and image quality in pediatric chest CT: effects of iterative reconstruction in normal weight and overweight children

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Haesung; Kim, Myung-Joon; Shin, Hyun Joo; Kim, Hyun Gi; Lee, Mi-Jung [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Seoul (Korea, Republic of); Yoon, Choon-Sik [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Choi, Jiin [Yonsei University College of Medicine, Biostatistics Collaboration Unit, Seoul (Korea, Republic of)

    2015-03-01

    New CT reconstruction techniques may help reduce the burden of ionizing radiation. To quantify radiation dose reduction when performing pediatric chest CT using a low-dose protocol and 50% adaptive statistical iterative reconstruction (ASIR) compared with age/gender-matched chest CT using a conventional dose protocol and reconstructed with filtered back projection (control group) and to determine its effect on image quality in normal weight and overweight children. We retrospectively reviewed 40 pediatric chest CT (M:F = 21:19; range: 0.1-17 years) in both groups. Radiation dose was compared between the two groups using paired Student's t-test. Image quality including noise, sharpness, artifacts and diagnostic acceptability was subjectively assessed by three pediatric radiologists using a four-point scale (superior, average, suboptimal, unacceptable). Eight children in the ASIR group and seven in the control group were overweight. All radiation dose parameters were significantly lower in the ASIR group (P < 0.01) with a greater than 57% dose reduction in overweight children. Image noise was higher in the ASIR group in both normal weight and overweight children. Only one scan in the ASIR group (1/40, 2.5%) was rated as diagnostically suboptimal and there was no unacceptable study. In both normal weight and overweight children, the ASIR technique is associated with a greater than 57% mean dose reduction, without significantly impacting diagnostic image quality in pediatric chest CT examinations. However, CT scans in overweight children may have a greater noise level, even when using the ASIR technique. (orig.)

  16. Doses of Tktazzus Tbxoid '

    African Journals Online (AJOL)

    Summary. Famnde O], Familusi ]B. Post—neonatal Tetanus in Nigeria: A Need for Booster. Doses of Tetanus Toxoid. 1V1_'gen'an journal ofPaediatn'cs 2001; 28:35. Eighty-two (87 per cent) of the 94- cases of post-neonatal tetanus patients seen in the department of paediatrics,. University College Hospital, Ibadan, over an ...

  17. Ibuprofen dosing for children

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000772.htm Ibuprofen dosing for children To use the sharing features on this page, ... much of this medicine can be harmful. How Ibuprofen can Help Your Child Ibuprofen is a type of nonsteroidal anti-inflammatory ...

  18. Biological dose estimation

    African Journals Online (AJOL)

    to this effect was found in at least 3 cases using biological dosimetric criteria, proving the ... The classification system described by Savage3 was used to determine the ... TABLE I. DISTANCE FROM RADIATION SOURCE, DETAILS OF CYTOGENETIC ANALYSIS AND BIOLOGICAL AND PHYSICAL. DOSE ESTIMATIONS.

  19. Dose Reduction Techniques

    CERN Document Server

    Waggoner, L O

    2000-01-01

    As radiation safety specialists, one of the things we are required to do is evaluate tools, equipment, materials and work practices and decide whether the use of these products or work practices will reduce radiation dose or risk to the environment. There is a tendency for many workers that work with radioactive material to accomplish radiological work the same way they have always done it rather than look for new technology or change their work practices. New technology is being developed all the time that can make radiological work easier and result in less radiation dose to the worker or reduce the possibility that contamination will be spread to the environment. As we discuss the various tools and techniques that reduce radiation dose, keep in mind that the radiological controls should be reasonable. We can not always get the dose to zero, so we must try to accomplish the work efficiently and cost-effectively. There are times we may have to accept there is only so much you can do. The goal is to do the sm...

  20. Dose specification for radiation therapy: dose to water or dose to medium?

    Science.gov (United States)

    Ma, C.-M.; Li, Jinsheng

    2011-05-01

    The Monte Carlo method enables accurate dose calculation for radiation therapy treatment planning and has been implemented in some commercial treatment planning systems. Unlike conventional dose calculation algorithms that provide patient dose information in terms of dose to water with variable electron density, the Monte Carlo method calculates the energy deposition in different media and expresses dose to a medium. This paper discusses the differences in dose calculated using water with different electron densities and that calculated for different biological media and the clinical issues on dose specification including dose prescription and plan evaluation using dose to water and dose to medium. We will demonstrate that conventional photon dose calculation algorithms compute doses similar to those simulated by Monte Carlo using water with different electron densities, which are close (doses to media but significantly different (up to 11%) from doses to water converted from doses to media following American Association of Physicists in Medicine (AAPM) Task Group 105 recommendations. Our results suggest that for consistency with previous radiation therapy experience Monte Carlo photon algorithms report dose to medium for radiotherapy dose prescription, treatment plan evaluation and treatment outcome analysis.

  1. Survey on immunotherapy practice patterns: dose, dose adjustments, and duration.

    Science.gov (United States)

    Larenas-Linnemann, Désirée E S; Gupta, Payel; Mithani, Sima; Ponda, Punita

    2012-05-01

    Practical issues dealing with the administration of allergen immunotherapy (AIT) by European and US allergists are not well known. Several concerns are only partially covered by guidelines. To survey AIT practice patterns among worldwide members of the American Academy of Allergy, Asthma and Immunology (AAAAI). A web-based survey was conducted among AAAAI members on dosing, dose adjustment after missed doses, and duration of AIT. A total of 1,201 replies (24.7% response rate of which 10% of responses were from non-US and non-Canada members). A total of 57% to 65% of the US-Canadian dosing falls within the recommended Practice Parameter ranges (9.4%-19% too low). Dose adjustment after missed doses is based on time elapsed since the last administered dose by 77% of US-Canadian and 58% of non-US-Canadian allergists. Doses are reduced when a patient comes in more than 14 days for 5 weeks after the last administration and initial dosing restarted after more than 30 days for 12 weeks since last administration during the build-up or maintenance stage. After missing 1 to 3 doses, the dosing schedules were mostly followed (build-up phase: repeat last dose, reduce by 1 dose, reduce by 2doses; maintenance phase: reduce by 1 dose, reduce by 2 doses, reduce by 3 doses). AIT is prescribed for a median of 3 years by non-US-Canadian allergists but for a median of 5 years by 75% of US-Canadian allergists. Main reasons for continuing beyond 5 years were "after stopping, symptoms reappeared" or "patient afraid to relapse." Many patients receive less than recommended doses. Two areas in which to plan further research are establishment of an optimal dose-adjustment plan for missed applications and exploration of the maximum appropriate duration of immunotherapy. Copyright © 2012 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  2. Smartphone apps for calculating insulin dose: a systematic assessment.

    Science.gov (United States)

    Huckvale, Kit; Adomaviciute, Samanta; Prieto, José Tomás; Leow, Melvin Khee-Shing; Car, Josip

    2015-05-06

    subtle harms resulting from suboptimal glucose control. Healthcare professionals should exercise substantial caution in recommending unregulated dose calculators to patients and address app safety as part of self-management education. The prevalence of errors attributable to incorrect interpretation of medical principles underlines the importance of clinical input during app design. Systemic issues affecting the safety and suitability of higher-risk apps may require coordinated surveillance and action at national and international levels involving regulators, health agencies and app stores.

  3. Detecting suboptimal cognitive effort: classification accuracy of the Conner's Continuous Performance Test-II, Brief Test Of Attention, and Trail Making Test.

    Science.gov (United States)

    Busse, Michelle; Whiteside, Douglas

    2012-01-01

    Many cognitive measures have been studied for their ability to detect suboptimal cognitive effort; however, attention measures have not been extensively researched. The current study evaluated the classification accuracy of commonly used attention/concentration measures, the Brief Test of Attention (BTA), Trail Making Test (TMT), and the Conners' Continuous Performance Test (CPT-II). Participants included 413 consecutive patients who completed a comprehensive neuropsychological evaluation. Participants were separated into two groups, identified as either unbiased responders or biased responders as determined by performance on the TOMM. Based on Mann-Whitney U results, the two groups differed significantly on all attentional measures. Classification accuracy of the BTA (.83), CPT-II omission errors (OE; .76) and TMT B (.75) were acceptable; however, classification accuracy of CPT-II commission errors (CE; .64) and TMT A (.62) were poor. When variables were combined in different combinations, sensitivity did not significantly increase. Results indicated for optimal cut-off scores, sensitivity ranged from 48% to 64% when specificity was at least 85%. Given that sensitivity rates were not adequate, there remains a need to utilize highly sensitive measures in addition to these embedded measures. Results were discussed within the context of research promoting the need for multiple measures of cognitive effort.

  4. Initial suboptimal CD4 reconstitution with antiretroviral therapy despite full viral suppression in a cohort of HIV-infected patients in Senegal.

    Science.gov (United States)

    Batista, G; Buvé, A; Ngom Gueye, N F; Manga, N M; Diop, M N; Ndiaye, K; Thiam, A; Ly, F; Diallo, A; Ndour, C T; Seydi, M

    2015-06-01

    We determined the risk factors and incidence of clinical events associated with suboptimal immune reconstitution (SIR) defined by an increase in CD4 inferior to 50 cells/μL, from inclusion up to six months of antiretroviral treatment (ARVT), in patients with an undetectable viral load ( 40 years (aOR = 1.74, 95% CI = 1.10-2.75), baseline CD4 ≥ 100 cells/μL (aOR = 2.06, 95% CI = 1.24-3.42), ARVT including AZT (aOR = 4.57, 95% CI=1.06-19.76), and the occurrence of a severe opportunistic infection during the first semester of ARVT (aOR = 2.38 95% CI= 1.49-3.80) were associated with SIR. After six months of ARVT and up to seven years of follow-up, 39 patients with SIR had presented with an opportunistic infection or death (rate= 9.78/100 person-years) compared to 168 with a normal recovery (rate = 7.75/100 person-years) but the difference was not statistically significant (aHR = 1.22, 95% CI = 0.85 to 1.74). SIR is less common in our country and is not associated with increased mortality or a greater incidence of opportunistic infections after six months of ARVT. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  5. Food Insecurity, Poor Diet Quality, and Suboptimal Intakes of Folate and Iron Are Independently Associated with Perceived Mental Health in Canadian Adults.

    Science.gov (United States)

    Davison, Karen M; Gondara, Lovedeep; Kaplan, Bonnie J

    2017-03-14

    To address nutrition-related population mental health data gaps, we examined relationships among food insecurity, diet quality, and perceived mental health. Stratified and logistic regression analyses of respondents aged 19-70 years from the Canadian Community Health Survey, Cycle 2.2 were conducted ( n = 15,546). Measures included the Household Food Security Survey Module, diet quality (i.e., comparisons to the Dietary Reference Intakes , Healthy Eating Index), perceived mental health (poor versus good), sociodemographics, and smoking. In this sample, 6.9% were food insecure and 4.5% reported poor mental health. Stratified analysis of food security and mental health status by age/gender found associations for poor diet quality, protein, fat, fibre, and several micronutrients ( p -values mental health emerged for food insecurity (OR = 1.60, 95% CI 1.45-1.71), poor diet quality (1.61, 95% CI 1.34-1.81), and suboptimal intakes of folate (OR = 1.58, 95% CI 1.17-1.90) and iron (OR = 1.45, 95% CI 1.23-1.88). Population approaches that improve food security and intakes of high quality diets may protect people from poor mental health.

  6. Association of suboptimal health status with psychosocial stress, plasma cortisol and mRNA expression of glucocorticoid receptor α/β in lymphocyte.

    Science.gov (United States)

    Yan, Yu-Xiang; Dong, Jing; Liu, You-Qin; Zhang, Jie; Song, Man-Shu; He, Yan; Wang, Wei

    2015-01-01

    Suboptimal health status (SHS) has become a new public health challenge in China. This study investigated whether high SHS is associated with psychosocial stress, changes in cortisol level and/or glucocorticoid receptor (GR) isoform expression. Three-hundred eighty-six workers employed in three companies in Beijing were recruited. The SHS score was derived from data collection in the SHS questionnaire (SHSQ-25). The short standard version of the Copenhagen Psychosocial Questionnaire (COPSOQ) was used to assess job-related psychosocial stress. The mean value of the five scales of COPSOQ and distribution of plasma cortisol and mRNA expression of GRα/GRβ between the high level of SHS group and the low level of SHS group were compared using a general linear model procedure. Multiple linear regression analysis was used to analyze the effect of psychosocial stress on SHS. We identified three factors that were predictive of SHS, including "demands at work", "interpersonal relations and leadership" and "insecurity at work". Significantly higher levels of plasma cortisol and GRβ/GRα mRNA ratio were observed among the high SHS group. High level of SHS is associated with decreased mRNA expression of GRα. This study confirmed the association between chronic psychosocial stress and SHS, indicating that improving the psychosocial work environment may reduce SHS and then prevent chronic diseases effectively.

  7. Rotavirus-specific IgA Responses Are Impaired and Serve as a Sub-Optimal Correlate of Protection among Infants in Bangladesh.

    Science.gov (United States)

    Lee, Benjamin; Carmolli, Marya; Dickson, Dorothy M; Colgate, E Ross; Diehl, Sean A; Uddin, Muhammad Ikhtear; Islam, Shahidul; Hossain, Motaher; Rafique, Tanzeem Ahmed; Bhuiyan, Taufiqur Rahman; Alam, Masud; Nayak, Uma; Mychaleckyj, Josyf C; McNeal, Monica M; Petri, William A; Qadri, Firdausi; Haque, Rashidul; Kirkpatrick, Beth D

    2018-01-31

    Rotavirus-specific IgA (RV-IgA) responses following oral RV vaccination are impaired in low-income countries, where the utility of RV-IgA as a correlate of protection (CoP) remains unclear. In a monovalent oral RV (Rotarix™) vaccine efficacy trial among infants in Dhaka, Bangladesh, we identified factors associated with poor RV-IgA responses and explored the utility of RV-IgA as a CoP. Infants were randomized to receive Rotarix™ or no Rotarix™ at 10 and 17 weeks of life and followed with active diarrheal surveillance. RV-IgA concentration, seroconversion, and seropositivity were determined at 18 weeks of life and analyzed for correlation(s) with rotavirus diarrhea (RVD) and for contribution to Rotarix™ vaccine effect. Among vaccinated infants, overall RV-IgA geometric mean concentration was 21 U/mL; only 27% seroconverted and 32% were seropositive after vaccination. Increased RV-specific maternal antibodies significantly impaired immunogenicity. Seroconversion was associated with reduced risk of RVD through one year of life, but RV-IgA seropositivity only explained 7.8% of the vaccine effect demonstrated by the clinical endpoint (RVD). RV-IgA responses were low among infants in Bangladesh and were significantly impaired by maternal antibodies. RV-IgA is a sub-optimal CoP in this setting; an improved CoP for RV in low-income countries is needed. NCT01375647.

  8. Entrance surface dose according to dose calculation: Head and wrist

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Ho Jin [Dept. Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of); Han, Jae Bok; Song, Jong Nam; Choi, Nam Gil [Dept. of Radiological Science, Dongshin University, Naju (Korea, Republic of)

    2016-09-15

    This study were compared with the direct measurement and indirect dose methods through various dose calculation in head and wrist. And, the modified equation was proposed considering equipment type, setting conditions, tube voltage, inherent filter, added filter and its accompanied back scatter factor. As a result, it decreased the error of the direct measurement than the existing dose calculation. Accordingly, diagnostic radiography patient dose comparison would become easier and radiographic exposure control and evaluation will become more efficient. The study findings are expected to be useful in patients' effective dose rate evaluation and dose reduction.

  9. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  10. Small dose... big poison.

    Science.gov (United States)

    Braitberg, George; Oakley, Ed

    2010-11-01

    It is not possible to identify all toxic substances in a single journal article. However, there are some exposures that in small doses are potentially fatal. Many of these exposures are particularly toxic to children. Using data from poison control centres, it is possible to recognise this group of exposures. This article provides information to assist the general practitioner to identify potential toxic substance exposures in children. In this article the authors report the signs and symptoms of toxic exposures and identify the time of onset. Where clear recommendations on the period of observation and known fatal dose are available, these are provided. We do not discuss management or disposition, and advise readers to contact the Poison Information Service or a toxicologist for this advice.

  11. Platelet testing to guide aspirin dose adjustment in pediatric patients after cardiac surgery.

    Science.gov (United States)

    Emani, Sirisha; Zurakowski, David; Mulone, Michelle; DiNardo, James A; Trenor, Cameron C; Emani, Sitaram M

    2017-11-01

    Thrombosis is associated with increased morbidity and mortality in pediatric patients undergoing cardiac surgery. Although aspirin commonly is used for thromboprophylaxis, the utility of laboratory-based tests that assess aspirin efficacy have not been evaluated. We sought to determine the relationship between platelet aggregation testing and aspirin dose adjustment on thrombosis rates in this population. Pediatric patients undergoing cardiac surgery who received aspirin and underwent platelet testing were studied retrospectively. Patients were excluded if they were treated with multiple agents or experienced thrombosis before the initiation of aspirin. Thrombosis events within 30 days after initiation of aspirin were recorded. Associations between aspirin responsiveness and thrombosis rate and aspirin dose adjustment and thrombosis rate were assessed with the use of multivariable logistic regression analysis. Suboptimal platelet response to aspirin was detected in 64 of 430 patients (15%) and thrombosis was detected in 11 patients (2.6%). Lack of aspirin responsiveness on initial testing was a significant risk factor for thrombosis (P aspirin dose. Dose escalation based on aspirin testing was performed in 40 of 64 patients, and significantly lower rate of thrombosis was observed in patients who underwent dose escalation compared with those without dose escalation (0/40 vs 9/24, P aspirin dose after initial unresponsiveness (P aspirin dosing may lead to subtherapeutic platelet inhibition in some children. Aspirin unresponsiveness is associated with increased risk of thrombosis after specific pediatric cardiac surgical procedures. Aspirin dose increase in unresponsive patients is associated with reduced risk of thrombosis. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  12. First dose in man

    DEFF Research Database (Denmark)

    Hougaard Christensen, Mette Marie

    2011-01-01

    Du er blevet ansat som læge i et lægemiddelfirma med ansvar for planlægning og sikkerhed i fase 1 forsøg. Firmaet har udviklet tre dopamin D2-receptor antagonister til behandling af skizofreni. Lægemidlerne har undergået et omfattende farmakologisk, toksikologisk og farmaceutisk afprøvningsprogra...... fase 1 forsøg alias »First dose in man«....

  13. Impact of Prior Inappropriate Fluconazole Dosing on Isolation of Fluconazole-Nonsusceptible Candida Species in Hospitalized Patients with Candidemia

    Science.gov (United States)

    Shah, Dhara N.; Yau, Raymond; Lasco, Todd M.; Weston, Jaye; Salazar, Miguel; Palmer, Hannah R.

    2012-01-01

    Prior use of fluconazole is a modifiable risk factor for the isolation of fluconazole-nonsusceptible Candida species. Optimization of the use of fluconazole by appropriate dose or duration may be able to minimize the risk of resistance. The objective of this study was to evaluate the effects of prior fluconazole therapy, including the dose and duration, on fluconazole susceptibility among Candida species isolated from hospitalized patients with candidemia. A retrospective cohort study of hospitalized patients with a first occurrence of nosocomial candidemia, from 2006 to 2009, was carried out. The relationships between the initial dose and duration of prior fluconazole therapy and the isolation of fluconazole-nonsusceptible Candida species were assessed. An initial fluconazole dose greater than 2 mg/kg and less than 6 mg/kg of body weight was considered suboptimal. A total of 177 patients were identified, of whom 133 patients aged 61 ± 16 years (56% male, 51% Caucasian, 51% with an APACHE II score of ≥15) had candidemia more than 2 days after the hospital admission day. Nine of 107 (8%) patients with fluconazole-susceptible Candida species and 9 of 26 (35%) patients with fluconazole-nonsusceptible Candida species had prior fluconazole exposure (risk ratio [RR], 3.03; 95% confidence interval [95% CI], 1.57 to 5.86; P, 0.0022). Preexposure with an initial dose of fluconazole greater than 2 mg/kg and less than 6 mg/kg occurred in 3 of 9 (33%) and 8 of 9 (89%) patients with fluconazole-susceptible and fluconazole-nonsusceptible Candida species, respectively (P, 0.0498). We conclude that patients with candidemia due to fluconazole-nonsusceptible Candida species were more likely to have received prior fluconazole therapy. Suboptimal initial dosing of prior fluconazole therapy was associated with candidemia with fluconazole-nonsusceptible Candida species. PMID:22411611

  14. Failure Rate of Single Dose Methotrexate in Managment of Ectopic Pregnancy

    Directory of Open Access Journals (Sweden)

    Feras Sendy

    2015-01-01

    Full Text Available Background. One of the treatment modalities for ectopic pregnancy is methotrexate. The purpose of this study is to identify the failure rate of methotrexate in treating patients with ectopic pregnancy as well as the risk factors leading to treatment failure. Methods. A retrospective chart review of 225 patients who received methotrexate as a primary management option for ectopic pregnancy. Failure of single dose of methotrexate was defined as drop of BHCG level less than or equal to 14% in the seventh day after administration of methotrexate. Results. 225 patients had methotrexate. Most of the patients (151 (67% received methotrexate based on the following formula: f 50 mg X body surface area. Single dose of methotrexate was successful in 72% (162/225 of the patients. 28% (63/225 were labeled as failure of single dose of methotrexate because of suboptimal drop in BhCG. 63% (40/63 of failure received a second dose of methotrexate, and 37% (23/63 underwent surgical treatment. Among patient who received initial dose of methotrexate, 71% had moderate or severe pain, and 58% had ectopic mass size of more than 4 cm on ultrasound. Conclusion. Liberal use of medical treatment of ectopic pregnancy results in 71% success rate.

  15. Failure Rate of Single Dose Methotrexate in Managment of Ectopic Pregnancy

    Science.gov (United States)

    Sendy, Feras; AlShehri, Eman; AlAjmi, Amani; Bamanie, Elham; Appani, Surekha; Shams, Taghreed

    2015-01-01

    Background. One of the treatment modalities for ectopic pregnancy is methotrexate. The purpose of this study is to identify the failure rate of methotrexate in treating patients with ectopic pregnancy as well as the risk factors leading to treatment failure. Methods. A retrospective chart review of 225 patients who received methotrexate as a primary management option for ectopic pregnancy. Failure of single dose of methotrexate was defined as drop of BHCG level less than or equal to 14% in the seventh day after administration of methotrexate. Results. 225 patients had methotrexate. Most of the patients (151 (67%)) received methotrexate based on the following formula: f 50 mg X body surface area. Single dose of methotrexate was successful in 72% (162/225) of the patients. 28% (63/225) were labeled as failure of single dose of methotrexate because of suboptimal drop in BhCG. 63% (40/63) of failure received a second dose of methotrexate, and 37% (23/63) underwent surgical treatment. Among patient who received initial dose of methotrexate, 71% had moderate or severe pain, and 58% had ectopic mass size of more than 4 cm on ultrasound. Conclusion. Liberal use of medical treatment of ectopic pregnancy results in 71% success rate. PMID:25861275

  16. Transit dose calculation in high dose rate brachytherapy (HDR ...

    African Journals Online (AJOL)

    Transit doses around a high dose rate 192Ir brachytherapy source were calculated using Sievert Integral at positions where the moving source was located exactly between two adjacent dwell positions. The correspond-ing transit dose rates were obtained by using energy absorption coefficients. Discrete step sizes of 0.25 ...

  17. Peritoneal Dialysis Dose and Adequacy

    Science.gov (United States)

    ... Navigation Peritoneal Dialysis Peritoneal Dialysis: Dose & Adequacy Peritoneal Dialysis: Dose & Adequacy When kidneys fail, waste products such ... absorbed from the abdominal cavity. Types of Peritoneal Dialysis The two types of peritoneal dialysis differ mainly ...

  18. Lower Incidence of End-Stage Renal Disease but Suboptimal Pre-Dialysis Renal Care in Schizophrenia: A 14-Year Nationwide Cohort Study.

    Science.gov (United States)

    Hsu, Yueh-Han; Cheng, Jur-Shan; Ouyang, Wen-Chen; Lin, Chen-Li; Huang, Chi-Ting; Hsu, Chih-Cheng

    2015-01-01

    Schizophrenia is closely associated with cardiovascular risk factors which are consequently attributable to the development of chronic kidney disease and end-stage renal disease (ESRD). However, no study has been conducted to examine ESRD-related epidemiology and quality of care before starting dialysis for patients with schizophrenia. By using nationwide health insurance databases, we identified 54,361 ESRD-free patients with schizophrenia and their age-/gender-matched subjects without schizophrenia for this retrospective cohort study (the schizophrenia cohort). We also identified a cohort of 1,244 adult dialysis patients with and without schizophrenia (1:3) to compare quality of renal care before dialysis and outcomes (the dialysis cohort). Cox proportional hazard models were used to estimate the hazard ratio (HR) for dialysis and death. Odds ratio (OR) derived from logistic regression models were used to delineate quality of pre-dialysis renal care. Compared to general population, patients with schizophrenia were less likely to develop ESRD (HR = 0.6; 95% CI 0.4-0.8), but had a higher risk for death (HR = 1.2; 95% CI, 1.1-1.3). Patients with schizophrenia at the pre-ESRD stage received suboptimal pre-dialysis renal care; for example, they were less likely to visit nephrologists (OR = 0.6; 95% CI, 0.4-0.8) and received fewer erythropoietin prescriptions (OR = 0.7; 95% CI, 0.6-0.9). But they had a higher risk of hospitalization in the first year after starting dialysis (OR = 1.4; 95% CI, 1.0-1.8, P dialysis had higher risk for mortality than the general ESRD patients. A closer collaboration between psychiatrists and nephrologists or internists to minimize the gaps in quality of general care is recommended.

  19. Lower Incidence of End-Stage Renal Disease but Suboptimal Pre-Dialysis Renal Care in Schizophrenia: A 14-Year Nationwide Cohort Study.

    Directory of Open Access Journals (Sweden)

    Yueh-Han Hsu

    Full Text Available Schizophrenia is closely associated with cardiovascular risk factors which are consequently attributable to the development of chronic kidney disease and end-stage renal disease (ESRD. However, no study has been conducted to examine ESRD-related epidemiology and quality of care before starting dialysis for patients with schizophrenia. By using nationwide health insurance databases, we identified 54,361 ESRD-free patients with schizophrenia and their age-/gender-matched subjects without schizophrenia for this retrospective cohort study (the schizophrenia cohort. We also identified a cohort of 1,244 adult dialysis patients with and without schizophrenia (1:3 to compare quality of renal care before dialysis and outcomes (the dialysis cohort. Cox proportional hazard models were used to estimate the hazard ratio (HR for dialysis and death. Odds ratio (OR derived from logistic regression models were used to delineate quality of pre-dialysis renal care. Compared to general population, patients with schizophrenia were less likely to develop ESRD (HR = 0.6; 95% CI 0.4-0.8, but had a higher risk for death (HR = 1.2; 95% CI, 1.1-1.3. Patients with schizophrenia at the pre-ESRD stage received suboptimal pre-dialysis renal care; for example, they were less likely to visit nephrologists (OR = 0.6; 95% CI, 0.4-0.8 and received fewer erythropoietin prescriptions (OR = 0.7; 95% CI, 0.6-0.9. But they had a higher risk of hospitalization in the first year after starting dialysis (OR = 1.4; 95% CI, 1.0-1.8, P < .05. Patients with schizophrenia undertaking dialysis had higher risk for mortality than the general ESRD patients. A closer collaboration between psychiatrists and nephrologists or internists to minimize the gaps in quality of general care is recommended.

  20. The Role of Healthy Lifestyle in the Implementation of Regressing Suboptimal Health Status among College Students in China: A Nested Case-Control Study.

    Science.gov (United States)

    Chen, Jieyu; Xiang, Hongjie; Jiang, Pingping; Yu, Lin; Jing, Yuan; Li, Fei; Wu, Shengwei; Fu, Xiuqiong; Liu, Yanyan; Kwan, Hiuyee; Luo, Ren; Zhao, Xiaoshan; Sun, Xiaomin

    2017-02-28

    Suboptimal health status (SHS) is the intermediate health state between health and disease, it is medically undiagnosed and is also termed functional somatic syndrome. Although its clinical manifestations are complicated and various, SHS has not reached the disease status. Unhealthy lifestyle is associated with many chronic diseases and mortality. In accordance with the impact of lifestyle on health, it is intriguing to determine the association between unhealthy lifestyle and SHS risk. We conducted a nested case-control study among healthy Chinese college students from March 2012 to September 2013, which was nested in a prospective cohort of 5676 students. We performed 1:1 incidence density sampling with matched controls for birth year, sex, grade, specialty and individual character. SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0). Exposure was defined as an unhealthy lifestyle per the frequency of six behavioral dimensions from the Health-promoting Lifestyle Profile (HPLP-II). We matched 543 cases of SHS (42.66%) in a cohort of 1273 students during the 1.5 years mean follow-up time with controls. A significant difference (t = 9.79, p lifestyle behavior with respect to behavioral dimensions significantly affected SHS likelihood. Further analyses revealed a marked increase (average increased 14.73 points) in lifestyle level among those SHS regression to health after 1.5 years, with respect to the HPLP-II behavioral dimensions, in addition to the total score (t = -15.34, p lifestyles, and the Int. J. Environ. Res. Public Health 2017, 14, 240 2 of 17 mitigation of modifiable lifestyle risk factors may lead to SHS regression. Increased efforts to modify unhealthy lifestyles are necessary to prevent SHS.

  1. Sub-optimal Testing and Awareness of HCV and HBV Among High Risk Individuals at an Underserved Safety-Net Hospital.

    Science.gov (United States)

    Wong, Robert J; Campbell, Brendan; Liu, Benny; Baden, Rachel; Bhuket, Taft

    2017-06-24

    Sub-optimal screening for chronic hepatitis C virus (HCV) and chronic hepatitis B virus (HBV) among high risk groups delays diagnosis and treatment. We aimed to evaluate overall rates of HCV and HBV screening and patient knowledge of their testing result. Adults age ≥18 years undergoing elective outpatient endoscopy at a large, urban safety-net hospital from July 2015 to July 2016 were prospectively evaluated to determine rates of HCV and HBV testing, the results of those completed tests, and patient knowledge of test results among high risk individuals (as determined by U.S. Preventative Services Task Force). Among 1125 patients (52.3% male, 70.4% foreign-born), 66.5% were high risk for chronic HCV; only 30.9% received prior testing. 14.7% had positive chronic HCV infection. Patients born in the 1945-1965 cohort were more likely to have received prior HCV testing compared to those born outside of this cohort (32.7 vs. 16.9%, p = 0.01). Among patients who received HCV screening, 29.3% were aware of test results. Overall, 61.6% were high risk for chronic HBV; only 25.1% received prior testing. 4.1% were positive for chronic HBV. Compared to Caucasians, Asians (19.0 vs. 44.4%, p HBV testing. Among patients who received prior HBV screening, 18.4% were aware of test results. Less than one-third of high risk patients received HCV and HBV screening among an ethnically diverse safety-net population. Equally low rates of patient knowledge of testing results were observed.

  2. An efficient method for the prediction of deleterious multiple-point mutations in the secondary structure of RNAs using suboptimal folding solutions

    Directory of Open Access Journals (Sweden)

    Barash Danny

    2008-04-01

    Full Text Available Abstract Background RNAmute is an interactive Java application which, given an RNA sequence, calculates the secondary structure of all single point mutations and organizes them into categories according to their similarity to the predicted structure of the wild type. The secondary structure predictions are performed using the Vienna RNA package. A more efficient implementation of RNAmute is needed, however, to extend from the case of single point mutations to the general case of multiple point mutations, which may often be desired for computational predictions alongside mutagenesis experiments. But analyzing multiple point mutations, a process that requires traversing all possible mutations, becomes highly expensive since the running time is O(nm for a sequence of length n with m-point mutations. Using Vienna's RNAsubopt, we present a method that selects only those mutations, based on stability considerations, which are likely to be conformational rearranging. The approach is best examined using the dot plot representation for RNA secondary structure. Results Using RNAsubopt, the suboptimal solutions for a given wild-type sequence are calculated once. Then, specific mutations are selected that are most likely to cause a conformational rearrangement. For an RNA sequence of about 100 nts and 3-point mutations (n = 100, m = 3, for example, the proposed method reduces the running time from several hours or even days to several minutes, thus enabling the practical application of RNAmute to the analysis of multiple-point mutations. Conclusion A highly efficient addition to RNAmute that is as user friendly as the original application but that facilitates the practical analysis of multiple-point mutations is presented. Such an extension can now be exploited prior to site-directed mutagenesis experiments by virologists, for example, who investigate the change of function in an RNA virus via mutations that disrupt important motifs in its secondary

  3. Atorvastatin reduces T-cell activation and exhaustion among HIV-infected cART-treated suboptimal immune responders in Uganda: a randomised crossover placebo-controlled trial.

    Science.gov (United States)

    Nakanjako, Damalie; Ssinabulya, Isaac; Nabatanzi, Rose; Bayigga, Lois; Kiragga, Agnes; Joloba, Moses; Kaleebu, Pontiano; Kambugu, Andrew D; Kamya, Moses R; Sekaly, Rafick; Elliott, Alison; Mayanja-Kizza, Harriet

    2015-03-01

    T-cell activation independently predicts mortality, poor immune recovery and non-AIDS illnesses during combination antiretroviral therapy (cART). Atorvastatin showed anti-immune activation effects among HIV-infected cART-naïve individuals. We investigated whether adjunct atorvastatin therapy reduces T-cell activation among cART-treated adults with suboptimal immune recovery. A randomised double-blind placebo-controlled crossover trial, of atorvastatin 80 mg daily vs. placebo for 12 weeks, was conducted among individuals with CD4 increase <295 cells/μl after seven years of suppressive cART. Change in T-cell activation (CD3 + CD4 + /CD8 + CD38 + HLADR+) and in T-cell exhaustion (CD3 + CD4 + /CD8 + PD1 + ) was measured using flow cytometry. Thirty patients were randomised, 15 to each arm. Atorvastatin resulted in a 28% greater reduction in CD4 T-cell activation (60% reduction) than placebo (32% reduction); P = 0.001. Atorvastatin also resulted in a 35% greater reduction in CD8-T-cell activation than placebo (49% vs. 14%, P = 0.0009), CD4 T-cell exhaustion (27% vs. 17% in placebo), P = 0.001 and CD8 T-cell exhaustion (27% vs. 16%), P = 0.004. There was no carry-over/period effect. Expected adverse events were comparable in both groups, and no serious adverse events were reported. Atorvastatin reduced T-cell immune activation and exhaustion among cART-treated adults in a Ugandan cohort. Atorvastatin adjunct therapy should be explored as a strategy to improve HIV treatment outcomes among people living with HIV in sub-Saharan Africa. © 2014 John Wiley & Sons Ltd.

  4. Suboptimal Weight Loss and Weight Regain after Gastric Bypass Surgery-Postoperative Status of Energy Intake, Eating Behavior, Physical Activity, and Psychometrics.

    Science.gov (United States)

    Amundsen, Tina; Strømmen, Magnus; Martins, Catia

    2017-05-01

    Suboptimal weight loss (SWL) and weight regain (WR) after gastric bypass surgery (GB) remains poorly understood. This study aims to compare GB patients experiencing SWL or significant WR (SigWR) with successful controls, regarding postoperative food intake, eating behavior, physical activity (PA), and psychometrics. Forty-nine patients with >1 year post-surgery were classified as either experiencing SWL (excess body weight loss, EWL, weight regain ≥15%, n = 38), with respective control groups. Energy intake (EI) was measured with a Food Frequency Questionnaire, eating behavior using the Dutch Eating Behavior Questionnaire and the Three-Factor Eating Questionnaire, and PA using both SenseWear Armbands and the International Physical Activity Questionnaire. Eating disorders, depression, and quality of life (QoL) were measured using the Eating Disorder Examination Questionnaire, Beck Depression Inventory II, and Impact of Weight on Quality of Life, respectively. EI, macronutrient distribution, and meal frequency were similar among groups. However, disinhibited eating behavior score was higher, while most subcategories from IWQOL were significantly lower in both SWL and SigWR groups compared with their respective controls. PA was significantly lower in the SWL and SigWR groups compared with the respective controls. There were no differences between groups regarding depression. Lower PA levels, disordered eating behavior and lower QoL are associated with unsuccessful weigh loss outcome after GB surgery. Longitudinal studies are needed to clarify the potential causal relationship between the previously described variables and SWL/SigWR after GB.

  5. Associations between breakfast eating habits and health-promoting lifestyle, suboptimal health status in Southern China: a population based, cross sectional study.

    Science.gov (United States)

    Chen, Jieyu; Cheng, Jingru; Liu, Yanyan; Tang, Yang; Sun, Xiaomin; Wang, Tian; Xiao, Ya; Li, Fei; Xiang, Lei; Jiang, Pingping; Wu, Shengwei; Wu, Liuguo; Luo, Ren; Zhao, Xiaoshan

    2014-12-11

    Suboptimal health status (SHS) is the intermediate health state between health and disease, refers to medically undiagnosed or functional somatic syndromes, and has been a major global public health challenge. However, both the etiology and mechanisms associated with SHS are still unclear. Breakfast eating behavior is a dietary pattern marker and previous studies have presented evidence of associations between failure to consume breakfast and increased diseases. Accordingly, in view of the significance of breakfast eating behaviors with respect to health status, the associations between breakfast eating habits and healthy lifestyle, SHS require further elucidation. A cross-sectional survey was conducted within a clustered sample of 24,159 individuals aged 12-80 years in 2012-13 within the population of Southern China. Breakfast eating habits were categorically defined by consumption frequency ('scarcely, sometimes or always'). Health-promoting lifestyle was assessed via the health-promoting lifestyle profile (HPLP-II). SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0). Of the 24,159 participants, the prevalence rates for the 'health' , 'SHS' , and 'disease' were 18.8%, 46.0%, and 35.2%, respectively. Overall, 19.6% of participants reported 'scarce' breakfast eating habits, with frequent breakfast eaters scoring higher on both HPLP-II and SHMS V1.0. After demographic adjustment, regression analyses revealed a significant association between breakfast eating habits and healthy lifestyle (p eating habits are significantly associated with a healthy lifestyle, and appear to be a useful predictor of a healthy lifestyle. Irregular breakfast eating habits are related to an increased risk of SHS; increased breakfast eating frequency may contribute to lowering the prevalence of SHS in Southern China.

  6. Assessing the Accuracy of High Resolution Digital Surface Models Computed by PhotoScan® and MicMac® in Sub-Optimal Survey Conditions

    Directory of Open Access Journals (Sweden)

    Marion Jaud

    2016-06-01

    Full Text Available For monitoring purposes and in the context of geomorphological research, Unmanned Aerial Vehicles (UAV appear to be a promising solution to provide multi-temporal Digital Surface Models (DSMs and orthophotographs. There are a variety of photogrammetric software tools available for UAV-based data. The objective of this study is to investigate the level of accuracy that can be achieved using two of these software tools: Agisoft PhotoScan® Pro and an open-source alternative, IGN© MicMac®, in sub-optimal survey conditions (rugged terrain, with a large variety of morphological features covering a range of roughness sizes, poor GPS reception. A set of UAV images has been taken by a hexacopter drone above the Rivière des Remparts, a river on Reunion Island. This site was chosen for its challenging survey conditions: the topography of the study area (i involved constraints on the flight plan; (ii implied errors on some GPS measurements; (iii prevented an optimal distribution of the Ground Control Points (GCPs and; (iv was very complex to reconstruct. Several image processing tests are performed with different scenarios in order to analyze the sensitivity of each software package to different parameters (image quality, numbers of GCPs, etc.. When computing the horizontal and vertical errors within a control region on a set of ground reference targets, both methods provide rather similar results. A precision up to 3–4 cm is achievable with these software packages. The DSM quality is also assessed over the entire study area comparing PhotoScan DSM and MicMac DSM with a Terrestrial Laser Scanner (TLS point cloud. PhotoScan and MicMac DSM are also compared at the scale of particular features. Both software packages provide satisfying results: PhotoScan is more straightforward to use but its source code is not open; MicMac is recommended for experimented users as it is more flexible.

  7. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, S.D.; Finch, S.M. (comps.)

    1992-10-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

  8. Efficacy of prokinetics with a split-dose of polyethylene glycol in bowel preparation for morning colonoscopy: a randomized controlled trial.

    Science.gov (United States)

    Kim, Hyoung Jun; Kim, Tae Oh; Shin, Bong Chul; Woo, Jae Gon; Seo, Eun Hee; Joo, Hee Rin; Heo, Nae-Yun; Park, Jongha; Park, Seung Ha; Yang, Sung Yeon; Moon, Young Soo; Shin, Jin-Yong; Lee, Nae Young

    2012-01-01

    Currently, a split-dose of polyethylene glycol (PEG) is the mainstay of bowel preparation due to its tolerability, bowel-cleansing action, and safety. However, bowel preparation with PEG is suboptimal because residual fluid reduces the polyp detection rate and requires a more thorough colon inspection. The aim of our study was to demonstrate the efficacy of a sufficient dose of prokinetics on bowel cleansing together with split-dose PEG. A prospective endoscopist-blinded study was conducted. Patients were randomly allocated to two groups: prokinetic with split-dose PEG or split-dose PEG alone. A prokinetic [100 mg itopride (Itomed)], was administered twice simultaneously with each split-dose of PEG. Bowel-cleansing efficacy was measured by endoscopists using the Ottawa scale and the segmental fluidity scale score. Each participant completed a bowel preparation survey. Mean scores from the Ottawa scale, segmental fluid scale, and rate of poor preparation were compared between both groups. Patients in the prokinetics with split-dose PEG group showed significantly lower total Ottawa and segmental fluid scores compared with patients in the split-dose of PEG alone group. A sufficient dose of prokinetics with a split-dose of PEG showed efficacy in bowel cleansing for morning colonoscopy, largely due to the reduction in colonic fluid. Copyright © 2012 S. Karger AG, Basel.

  9. Using Six Sigma to improve once daily gentamicin dosing and therapeutic drug monitoring performance.

    LENUS (Irish Health Repository)

    Egan, Sean

    2012-08-07

    BACKGROUND: Safe, effective therapy with the antimicrobial gentamicin requires good practice in dose selection and monitoring of serum levels. Suboptimal therapy occurs with breakdown in the process of drug dosing, serum blood sampling, laboratory processing and level interpretation. Unintentional underdosing may result. This improvement effort aimed to optimise this process in an academic teaching hospital using Six Sigma process improvement methodology. METHODS: A multidisciplinary project team was formed. Process measures considered critical to quality were defined, and baseline practice was examined through process mapping and audit. Root cause analysis informed improvement measures. These included a new dosing and monitoring schedule, and standardised assay sampling and drug administration timing which maximised local capabilities. Three iterations of the improvement cycle were conducted over a 24-month period. RESULTS: The attainment of serum level sampling in the required time window improved by 85% (p≤0.0001). A 66% improvement in accuracy of dosing was observed (p≤0.0001). Unnecessary dose omission while awaiting level results and inadvertent disruption to therapy due to dosing and monitoring process breakdown were eliminated. Average daily dose administered increased from 3.39 mg\\/kg to 4.78 mg\\/kg\\/day. CONCLUSIONS: Using Six Sigma methodology enhanced gentamicin usage process performance. Local process related factors may adversely affect adherence to practice guidelines for gentamicin, a drug which is complex to use. It is vital to adapt dosing guidance and monitoring requirements so that they are capable of being implemented in the clinical environment as a matter of routine. Improvement may be achieved through a structured localised approach with multidisciplinary stakeholder involvement.

  10. Dose-dependent Effects of mTOR Inhibition on Weight and Mitochondrial Disease in Mice

    Directory of Open Access Journals (Sweden)

    Simon C Johnson

    2015-07-01

    Full Text Available Rapamycin extends lifespan and attenuates age-related pathologies in mice when administered through diet at 14 parts per million (PPM. Recently, we reported that daily intraperitoneal injection of rapamycin at 8 mg/kg attenuates mitochondrial disease symptoms and progression in the Ndufs4 knockout mouse model of Leigh Syndrome. Although rapamycin is a widely used pharmaceutical agent dosage has not been rigorously examined and no dose-response profile has been established. Given these observations we sought to determine if increased doses of oral rapamycin would result in more robust impact on mTOR driven parameters. To test this hypothesis, we compared the effects of dietary rapamycin at doses ranging from 14 to 378 PPM on growth in control and Ndufs4 knockout mice and on health and survival in the Ndufs4 knockout model. High dose rapamycin was well tolerated, dramatically reduced growth, and overcame gender differences. The highest oral dose, approximately 27-times the dose shown to extend murine lifespan, increased survival in Ndufs4 knockout mice similarly to daily rapamycin injection without observable adverse effects. These findings have broad implications for the effective use of rapamycin in murine studies and for the translational potential of rapamycin in the treatment of mitochondrial disease. This data, further supported by a comparison of available literature, suggests that 14 PPM dietary rapamycin is a sub-optimal dose for targeting mTOR systemically in mice. Our findings suggest that the role of mTOR in mammalian biology may be broadly underestimated when determined through treatment with rapamycin at commonly used doses.

  11. Knowledge-based prediction of three-dimensional dose distributions for external beam radiotherapy.

    Science.gov (United States)

    Shiraishi, Satomi; Moore, Kevin L

    2016-01-01

    To demonstrate knowledge-based 3D dose prediction for external beam radiotherapy. Using previously treated plans as training data, an artificial neural network (ANN) was trained to predict a dose matrix based on patient-specific geometric and planning parameters, such as the closest distance (r) to planning target volume (PTV) and organ-at-risks (OARs). Twenty-three prostate and 43 stereotactic radiosurgery/radiotherapy (SRS/SRT) cases with at least one nearby OAR were studied. All were planned with volumetric-modulated arc therapy to prescription doses of 81 Gy for prostate and 12-30 Gy for SRS. Using these clinically approved plans, ANNs were trained to predict dose matrix and the predictive accuracy was evaluated using the dose difference between the clinical plan and prediction, δD = Dclin - Dpred. The mean (〈δDr〉), standard deviation (σδDr ), and their interquartile range (IQR) for the training plans were evaluated at a 2-3 mm interval from the PTV boundary (rPTV) to assess prediction bias and precision. Initially, unfiltered models which were trained using all plans in the cohorts were created for each treatment site. The models predict approximately the average quality of OAR sparing. Emphasizing a subset of plans that exhibited superior to the average OAR sparing during training, refined models were created to predict high-quality rectum sparing for prostate and brainstem sparing for SRS. Using the refined model, potentially suboptimal plans were identified where the model predicted further sparing of the OARs was achievable. Replans were performed to test if the OAR sparing could be improved as predicted by the model. The refined models demonstrated highly accurate dose distribution prediction. For prostate cases, the average prediction bias for all voxels irrespective of organ delineation ranged from -1% to 0% with maximum IQR of 3% over rPTV ∈ [ - 6, 30] mm. The average prediction error was less than 10% for the same rPTV range. For SRS cases

  12. Knowledge-based prediction of three-dimensional dose distributions for external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shiraishi, Satomi; Moore, Kevin L., E-mail: kevinmoore@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California 92093 (United States)

    2016-01-15

    Purpose: To demonstrate knowledge-based 3D dose prediction for external beam radiotherapy. Methods: Using previously treated plans as training data, an artificial neural network (ANN) was trained to predict a dose matrix based on patient-specific geometric and planning parameters, such as the closest distance (r) to planning target volume (PTV) and organ-at-risks (OARs). Twenty-three prostate and 43 stereotactic radiosurgery/radiotherapy (SRS/SRT) cases with at least one nearby OAR were studied. All were planned with volumetric-modulated arc therapy to prescription doses of 81 Gy for prostate and 12–30 Gy for SRS. Using these clinically approved plans, ANNs were trained to predict dose matrix and the predictive accuracy was evaluated using the dose difference between the clinical plan and prediction, δD = D{sub clin} − D{sub pred}. The mean (〈δD{sub r}〉), standard deviation (σ{sub δD{sub r}}), and their interquartile range (IQR) for the training plans were evaluated at a 2–3 mm interval from the PTV boundary (r{sub PTV}) to assess prediction bias and precision. Initially, unfiltered models which were trained using all plans in the cohorts were created for each treatment site. The models predict approximately the average quality of OAR sparing. Emphasizing a subset of plans that exhibited superior to the average OAR sparing during training, refined models were created to predict high-quality rectum sparing for prostate and brainstem sparing for SRS. Using the refined model, potentially suboptimal plans were identified where the model predicted further sparing of the OARs was achievable. Replans were performed to test if the OAR sparing could be improved as predicted by the model. Results: The refined models demonstrated highly accurate dose distribution prediction. For prostate cases, the average prediction bias for all voxels irrespective of organ delineation ranged from −1% to 0% with maximum IQR of 3% over r{sub PTV} ∈ [ − 6, 30] mm. The

  13. Dose determination in high dose-rate brachytherapy.

    Science.gov (United States)

    Houdek, P V; Schwade, J G; Wu, X; Pisciotta, V; Fiedler, J A; Serago, C F; Markoe, A M; Abitbol, A A; Lewin, A A; Braunschweiger, P G

    1992-01-01

    Although high dose-rate brachytherapy with a single, rapidly moving radiation source is becoming a common treatment modality, a suitable formalism for determination of the dose delivered by a moving radiation source has not yet been developed. At present, brachytherapy software simulates high dose-rate treatments using only a series of stationary sources, and consequently fails to account for the dose component delivered while the source is in motion. We now describe a practical model for determination of the true, total dose administered. The algorithm calculates both the dose delivered while the source is in motion within and outside of the implanted volume (dynamic component), and the dose delivered while the source is stationary at a series of fixed dwell points. It is shown that the dynamic dose element cannot be ignored because it always increases the dose at the prescription points and, in addition, distorts the dose distribution within and outside of the irradiated volume. Failure to account for the dynamic dose component results in dosimetric errors that range from significant (> 10%) to negligible (source activity, and source speed as defined by the implant geometry.

  14. Initiation of insulin glargine in patients with Type 2 diabetes in suboptimal glycaemic control positively impacts health-related quality of life. A prospective cohort study in primary care

    DEFF Research Database (Denmark)

    Hajós, Tibor R S; Pouwer, F; de Grooth, R

    2011-01-01

    AIMS: To study prospectively the impact of initiating insulin glargine in suboptimally controlled insulin-naïve patients with Type 2 diabetes on health-related quality of life in relation to glycaemic control. METHODS: Insulin-naïve Dutch patients with Type 2 diabetes in suboptimal glycaemic...... completed self-report health-related quality of life measures, including emotional well-being (World Health Organization-5 well-being index), fear of hypoglycaemia (Hypoglycaemia Fear Survey) and diabetes symptom distress (Diabetes Symptom Checklist-revised). Data were analysed using generalized estimating...... of this observational study demonstrate combined glycaemic and health-related quality of life benefits of initiating insulin glargine in patients with Type 2 diabetes in routine primary care....

  15. Solute clearance in CRRT: prescribed dose versus actual delivered dose.

    Science.gov (United States)

    Lyndon, William D; Wille, Keith M; Tolwani, Ashita J

    2012-03-01

    Substantial efforts have been made toward defining the dose threshold of continuous renal replacement therapy (CRRT) associated with improved survival in critically ill patients with acute kidney injury. Published studies have used prescribed effluent rates, expressed as total effluent volume (TEV) per weight and unit time (mL/kg/h), as a surrogate for dose. The purpose of this study was to compare differences in CRRT dose based on prescribed effluent rate, measured TEV and direct measurement of urea and creatinine clearance. We analyzed data that had been prospectively collected on 200 patients enrolled in a randomized trial comparing survival with a prescribed effluent rate of 20 mL/kg/h (standard dose) to 35 mL/kg/h (high dose) using pre-dilution continuous venovenous hemodiafiltration (CVVHDF). Filters were changed every 72 h. Blood urea nitrogen (BUN), serum creatinine (SCr), effluent urea nitrogen (EUN) and effluent creatinine (ECr) were collected daily. Actual delivered dose was calculated as: (EUN/BUN)*TEV for urea and (ECr/SCr)*TEV for creatinine. Data were available for 165 patients. In both groups, prescribed dose differed significantly from the measured TEV dose (P < 0.001). In the standard dose group, there was no difference between the measured TEV dose and actual delivered urea and creatinine clearances. However, in the high-dose group, measured TEV dose differed significantly from delivered urea clearance by 7.1% (P < 0.001) and creatinine clearance by 13.9% (P < 0.001). Dose based on prescribed effluent rate or measured TEV is a poor substitute for actual CVVHDF creatinine and urea clearance.

  16. Personalized exercise dose prescription.

    Science.gov (United States)

    Zubin Maslov, Petra; Schulman, Alexa; Lavie, Carl J; Narula, Jagat

    2017-12-28

    Physical activity (PA) is associated with increased longevity and decreased risk of cardiovascular disease, however, the majority of the general population is still sedentary. In order to maximize the health benefits of PA, health care practitioners should be familiarized with the appropriate dose of exercise for each healthy individual, depending on their habitual PA and relative fitness. The aim of this review is to quantitatively describe the lowest and the highest level of exercise that has health benefits, and what should hypothetically be considered 'the sweet spot'. Analysis of the current literature allows us to develop personalized 'exercise prescription' for healthy individuals. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2017. For permissions, please email: journals.permissions@oup.com.

  17. [Radiation exposure of children in pediatric radiology. Part 3: Conversion coefficients for reconstruction of organ doses achieved during chest X-ray examinations].

    Science.gov (United States)

    Seidenbusch, M C; Regulla, D; Schneider, K

    2008-12-01

    Calculation of conversion coefficients for the reconstruction of organ doses from entrance doses for chest radiographs of 0, 1, 5, 10, 15, and 30-year-old patients in conventional pediatric radiology for the radiographic settings recommended by the German and European guidelines for quality management in diagnostic radiology. The conversion coefficients for pediatric chest radiographs were calculated using the commercially available personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Säteilyturvakeskus STUK). PCXMC is a Monte Carlo program for computing organ and effective doses in about 40 organs of mathematical hermaphrodite phantom models describing patients of different ages. The possible clinical variation of beam collimation was taken into consideration by defining optimal and suboptimal radiation fields on the phantoms' surfaces. Conversion coefficients for the reconstruction of organ doses from measured entrance doses during chest radiographs for 0, 1, 5, 10, 15, and 30-year-old pediatric patients were presented. Conversion coefficients were calculated for the standard sagittal and lateral beam projections and the standard focus film distances of 100 cm, 115 cm, and 150 cm using the standard radiation qualities according to the recommendations of the German and European guidelines for quality management in diagnostic radiology. These conversion coefficients allow the reconstruction of the absorbed dose in about 40 organs and tissues of the human body for optimal and suboptimal radiation field collimations. The conversion coefficients presented in this paper may be used for organ dose assessments from entrance doses measured during chest radiographs of patients of all age groups with all beam collimations within optimal and suboptimal standard beam collimations. While the influence of the beam collimation on organ doses of organs localized near the center of the beam is expectedly low, the radiation exposure of

  18. Sub-optimal CD4 reconstitution despite viral suppression in an urban cohort on Antiretroviral Therapy (ART in sub-Saharan Africa: Frequency and clinical significance

    Directory of Open Access Journals (Sweden)

    Kamya Moses R

    2008-10-01

    Full Text Available Abstract Background A proportion of individuals who start antiretroviral therapy (ART fail to achieve adequate CD4 cell reconstitution despite sustained viral suppression. We determined the frequency and clinical significance of suboptimal CD4 reconstitution despite viral suppression (SO-CD4 in an urban HIV research cohort in Kampala, Uganda Methods We analyzed data from a prospective research cohort of 559 patients initiating ART between 04/04–04/05. We described the patterns of SO-CD4 both in terms of:- I magnitude of CD4 cell increase (a CD4 count increase Results Of 559 patients initiating ART, 386 (69% were female. Median (IQR age and baseline CD4 counts were 38 yrs (33–44 and 98 cells/μl (21–163 respectively; 414 (74% started a d4T-based regimen (D4T+3TC+NVP and 145 (26% a ZDV-based regimen (ZDV+3TC+EFV. After 6, 12 and 24 months of ART, 380 (68%, 339 (61% and 309 (55% had attained and sustained HIV-RNA viral suppression. Of these, 78 (21%, 151 (45% and 166 (54% respectively had SO-CD4 based on criteria I, and 165(43%, 143(42% and 58(19% respectively based on criteria II. With both criteria combined, 56 (15% and 129 (38% had SO-CD4 at 6 and 12 months respectively. A high proportion (82% and 58% of those that had SO-CD4 at 6 months (using criteria I maintained SO-CD4 at 12 and 24 months respectively. There were no statistically significant differences in the incidence of clinical events among patients with [19/100PYO (12–29] and without SO-CD4 [23/100PYO (19–28]. Conclusion Using criteria I, the frequency of SO-CD4 was 21% at 6 months. Majority of patients with SO-CD4 at 6 months maintained SO-CD4 up to 2 years. We recommend studies of CD4 T-cell functional recovery among patients with SO-CD4.

  19. The framing of research questions using the PICOT format in randomized controlled trials of venous ulcer disease is suboptimal: A systematic survey.

    Science.gov (United States)

    Abbade, Luciana P F; Wang, Mei; Sriganesh, Kamath; Jin, Yanling; Mbuagbaw, Lawrence; Thabane, Lehana

    2017-09-01

    Despite several publications on venous ulcers, there is still a lack of evidence from randomized controlled trials (RCTs) to support certain treatments for patients with this disorder. Well-designed research questions using the PICOT (Population; Intervention; Comparator; Outcome; Time-frame) format in RCTs can improve the quality of research. The objectives of this study were to assess how the PICOT format is used to frame research questions in RCTs published on venous ulcer disease and to determine the factors associated with better adherence to the PICOT format. We conducted a systematic survey of RCTs on venous ulcers published in the PubMed database between January 2009 and May 2016. All RCTs published in English addressing therapeutic interventions for venous ulcer disease in human subjects were included. We examined whether the five elements of the PICOT format were used in formulating the research question and scored them between 0 and 5. The primary outcome of this systematic survey was the percentage of studies that adequately reported all five PICOT elements. Eighty-five (85) RCTs were included with median PICOT score of 3 (IQR = 1.5). Four elements of PICOT were present in 28 reports (32.9%) and only 2 RCTS (2.3%) reported all the PICOT elements. Population and intervention were often appropriately described, in (70/85) 82.4% and (83/85) 97.6% of the studies, respectively; however, comparison intervention and outcome were presented in only (53/85) 62.3% and (48/85) 56.5% of studies, respectively. Very few RCTs (7.1%; 6/85) reported the study time frame. No journal or RCT characteristics were found to be significantly associated with better reporting. Use of the PICOT format to frame research questions in RCTs published on venous ulcers is suboptimal, and our study reinforces the importance of framing a good research question to improve the design of trials and quality of evidence in venous ulcer disease. © 2017 by the Wound Healing Society.

  20. The Role of Healthy Lifestyle in the Implementation of Regressing Suboptimal Health Status among College Students in China: A Nested Case-Control Study

    Science.gov (United States)

    Chen, Jieyu; Xiang, Hongjie; Jiang, Pingping; Yu, Lin; Jing, Yuan; Li, Fei; Wu, Shengwei; Fu, Xiuqiong; Liu, Yanyan; Kwan, Hiuyee; Luo, Ren; Zhao, Xiaoshan; Sun, Xiaomin

    2017-01-01

    Background: Suboptimal health status (SHS) is the intermediate health state between health and disease, it is medically undiagnosed and is also termed functional somatic syndrome. Although its clinical manifestations are complicated and various, SHS has not reached the disease status. Unhealthy lifestyle is associated with many chronic diseases and mortality. In accordance with the impact of lifestyle on health, it is intriguing to determine the association between unhealthy lifestyle and SHS risk. Methods: We conducted a nested case-control study among healthy Chinese college students from March 2012 to September 2013, which was nested in a prospective cohort of 5676 students. We performed 1:1 incidence density sampling with matched controls for birth year, sex, grade, specialty and individual character. SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0). Exposure was defined as an unhealthy lifestyle per the frequency of six behavioral dimensions from the Health-promoting Lifestyle Profile (HPLP-II). Results: We matched 543 cases of SHS (42.66%) in a cohort of 1273 students during the 1.5 years mean follow-up time with controls. A significant difference (t = 9.79, p < 0.001) and a reduction in HPLP-II total score was present at 1.5 years follow-up (135.93 ± 17.65) compared to baseline (144.48 ± 18.66). A level-response effect was recorded with an increase of the total HPLP-II (every dimension was correlated with a decreased SHS risk). Compared to respondents with the least exposure (excellent level), those reporting a general HPLP-II level were approximately 2.3 times more likely to develop SHS (odd ratio = 2.333, 95% CI = 1.471 to 3.700); and those with less HPLP-II level (good level) were approximately 1.6 times more likely (1.644, 1.119–2.414) to develop SHS (p < 0.05). Our data indicated that unhealthy lifestyle behavior with respect to behavioral dimensions significantly affected SHS likelihood

  1. A dietary dairy/yeast prebiotic and flaxseed oil enhance growth, hematological and immunological parameters in channel catfish at a suboptimal temperature (15°C).

    Science.gov (United States)

    Thompson, M; Lochmann, R; Phillips, H; Sink, T D

    2015-07-01

    Channel catfish raised in the southern United States require two growing seasons to reach market size. Growing seasons are separated by a cool period of about 3 months when feed intake and growth are greatly reduced. A cool-weather feeding strategy to improve feed intake, growth or health of catfish might improve survival and reduce the time needed to achieve market size. We conducted a feeding trial with channel catfish at a suboptimal temperature (15°C) to determine the effects of supplementing diets with either a dairy/yeast prebiotic or flaxseed oil (high in 18:3n-3) compared with a control with soybean oil (high in 18:2n-6). The trial was conducted in recirculating systems with 1140-l tanks containing 100 fish each (mean initial weight 61.4 g±0.43 s.e.m.). A 28%-protein basal diet was supplemented with 20 g/kg cellulose and 20 g/kg soybean oil (SBO, control), 20 g/kg cellulose and 20 g/kg flaxseed oil (FLAX) or 20 g/kg of a dairy/yeast prebiotic and 20 g/kg soybean oil (PREB). Fish were fed once daily to satiation and weighed every 3 weeks to track growth. Hematology, non-specific immune responses, proximate and fatty acid composition of muscle were determined to assess diet effects. Catfish-fed FLAX or PREB had higher weight gain, feed consumption and lysozyme activity than fish fed SBO. Total n-3 fatty acids in muscle were higher in fish fed SBO or FLAX than those fed PREB. Total n-6 long-chain polyunsaturated acids were higher in muscle of fish fed PREB than those fed SBO. Fatty acids in the PREB and SBO diets were similar, so the PREB appeared to increase elongation and desaturation of n-6 fatty acids in muscle. Flaxseed oil and the dairy/yeast prebiotic both have potential to increase catfish performance at a low temperature.

  2. Modulation of cortisol metabolism by low-dose growth hormone replacement in elderly hypopituitary patients.

    Science.gov (United States)

    Toogood, A A; Taylor, N F; Shalet, S M; Monson, J P

    2000-04-01

    11 beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) functions as a net reductase converting cortisone to cortisol. GH inhibits 11beta-HSD1, resulting in a shift in cortisol metabolism favoring cortisone, an observation that may have significance in patients with ACTH deficiency who are unable to compensate for such changes. We have studied the effect of three doses of GH replacement (0.17, 0.33, and 0.5 mg each given for 12 weeks in ascending order) on cortisol metabolism in nine patients, aged 62-70 yr, with hypopituitarism who were receiving fixed doses of oral hydrocortisone. Serum insulin-like growth factor I levels rose in a dose-dependent manner over the course of the study. Fat mass decreased significantly at 24 weeks (P = 0.02), a change that was maintained at 36 weeks. Fasting serum insulin levels did not change significantly over the course of the study. The ratio of urine cortisol to cortisone metabolites (Fm/Em) fell significantly at 12 weeks (GH dose, 0.17 mg/day) from 1.32 (0.91-2.20) at baseline to 1.08 (0.89-2.11) (P cortisol replacement is suboptimal, may be at risk of the clinical manifestations of cortisol deficiency when they are commenced on GH therapy.

  3. Experimental evaluation of neutron dose in radiotherapy patients: Which dose?

    Energy Technology Data Exchange (ETDEWEB)

    Romero-Expósito, M., E-mail: mariateresa.romero@uab.cat; Domingo, C.; Ortega-Gelabert, O.; Gallego, S. [Grup de Recerca en Radiacions Ionizants (GRRI), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra 08193 (Spain); Sánchez-Doblado, F. [Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla 41009 (Spain); Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla 41009 (Spain)

    2016-01-15

    Purpose: The evaluation of peripheral dose has become a relevant issue recently, in particular, the contribution of secondary neutrons. However, after the revision of the Recommendations of the International Commission on Radiological Protection, there has been a lack of experimental procedure for its evaluation. Specifically, the problem comes from the replacement of organ dose equivalent by the organ-equivalent dose, being the latter “immeasurable” by definition. Therefore, dose equivalent has to be still used although it needs the calculation of the radiation quality factor Q, which depends on the unrestricted linear energy transfer, for the specific neutron irradiation conditions. On the other hand, equivalent dose is computed through the radiation weighting factor w{sub R}, which can be easily calculated using the continuous function provided by the recommendations. The aim of the paper is to compare the dose equivalent evaluated following the definition, that is, using Q, with the values obtained by replacing the quality factor with w{sub R}. Methods: Dose equivalents were estimated in selected points inside a phantom. Two types of medical environments were chosen for the irradiations: a photon- and a proton-therapy facility. For the estimation of dose equivalent, a poly-allyl-diglicol-carbonate-based neutron dosimeter was used for neutron fluence measurements and, additionally, Monte Carlo simulations were performed to obtain the energy spectrum of the fluence in each point. Results: The main contribution to dose equivalent comes from neutrons with energy higher than 0.1 MeV, even when they represent the smallest contribution in fluence. For this range of energy, the radiation quality factor and the radiation weighting factor are approximately equal. Then, dose equivalents evaluated using both factors are compatible, with differences below 12%. Conclusions: Quality factor can be replaced by the radiation weighting factor in the evaluation of dose

  4. Organ Doses and Effective Doses in Pediatric Radiography: Patient-Dose Survey in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Kiljunen, T.; Tietaevaeinen, A.; Parviainen, T.; Viitala, A.; Kortesniemi, M. (Radiation Practices Regulation, Radiation and Nuclear Safety Authority, Helsinki (Finland))

    2009-01-15

    Background: Use of the effective dose in diagnostic radiology permits the radiation exposure of diverse diagnostic procedures to be quantified. Fundamental knowledge of patient doses enhances the implementation of the 'as low as reasonably achievable' (ALARA) principle. Purpose: To provide comparative information on pediatric examination protocols and patient doses in skull, sinus, chest, abdominal, and pelvic radiography examinations. Material and Methods: 24 Finnish hospitals were asked to register pediatric examination data, including patient information and examination parameters and specifications. The total number of examinations in the study was 1916 (1426 chest, 228 sinus, 96 abdominal, 94 skull, and 72 pelvic examinations). Entrance surface dose (ESD) and dose-area products (DAP) were calculated retrospectively or DAP meters were used. Organ doses and effective doses were determined using a Monte Carlo program (PCXMC). Results: There was considerable variation in examination protocols between different hospitals, indicating large variations in patient doses. Mean effective doses of different age groups ranged from 5 muSv to 14 muSv in skull and sinus examinations, from 25 muSv to 483 muSv in abdominal examinations, and from 6 muSv to 48 muSv in chest examinations. Conclusion: In chest and sinus examinations, the amount of data was extensive, allowing national pediatric diagnostic reference levels to be defined. Parameter selection in pediatric examination protocols should be harmonized in order to reduce patient doses and improve optimization

  5. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    Finch, S.M.; McMakin, A.H. (comps.)

    1992-06-01

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, and agriculture; environmental pathways and dose estimates.

  6. REMEDIATION FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    V. Arakali; E. Faillace

    2004-02-27

    The purpose of this design calculation is to estimate radiation doses received by personnel in the Remediation Facility performing operations to receive, prepare, open, repair, recover, disposition, and correct off-normal and non-standard conditions with casks, canisters, spent nuclear fuel (SNF) assemblies, and waste packages (WP). The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation. The results of this calculation will be used to support the design of the Remediation Facility and provide occupational dose estimates for the License Application.

  7. Do dose area product meter measurements reflect radiation doses ...

    African Journals Online (AJOL)

    Enrique

    between radiation doses absorbed by health care workers and dose area product meter (DAP) measurements at Universitas Hospital, Bloemfontein. The DAP is an instrument which accurately measures the radiation emitted from the source. The study included the interventional radiolo- gists, radiographers and nurses ...

  8. A dose error evaluation study for 4D dose calculations

    Science.gov (United States)

    Milz, Stefan; Wilkens, Jan J.; Ullrich, Wolfgang

    2014-10-01

    Previous studies have shown that respiration induced motion is not negligible for Stereotactic Body Radiation Therapy. The intrafractional breathing induced motion influences the delivered dose distribution on the underlying patient geometry such as the lung or the abdomen. If a static geometry is used, a planning process for these indications does not represent the entire dynamic process. The quality of a full 4D dose calculation approach depends on the dose coordinate transformation process between deformable geometries. This article provides an evaluation study that introduces an advanced method to verify the quality of numerical dose transformation generated by four different algorithms. The used transformation metric value is based on the deviation of the dose mass histogram (DMH) and the mean dose throughout dose transformation. The study compares the results of four algorithms. In general, two elementary approaches are used: dose mapping and energy transformation. Dose interpolation (DIM) and an advanced concept, so called divergent dose mapping model (dDMM), are used for dose mapping. The algorithms are compared to the basic energy transformation model (bETM) and the energy mass congruent mapping (EMCM). For evaluation 900 small sample regions of interest (ROI) are generated inside an exemplary lung geometry (4DCT). A homogeneous fluence distribution is assumed for dose calculation inside the ROIs. The dose transformations are performed with the four different algorithms. The study investigates the DMH-metric and the mean dose metric for different scenarios (voxel sizes: 8 mm, 4 mm, 2 mm, 1 mm 9 different breathing phases). dDMM achieves the best transformation accuracy in all measured test cases with 3-5% lower errors than the other models. The results of dDMM are reasonable and most efficient in this study, although the model is simple and easy to implement. The EMCM model also achieved suitable results, but the approach requires a more complex

  9. Effectiveness of NEM® brand eggshell membrane in the treatment of suboptimal joint function in dogs: a multicenter, randomized, double-blind, placebo-controlled study

    Directory of Open Access Journals (Sweden)

    Ruff KJ

    2016-08-01

    Full Text Available Kevin J Ruff,1 Kenneth J Kopp,2 Pamela Von Behrens,3 Mark Lux,4 Matthew Mahn,5 Matthew Back1 1ESM Technologies LLC, Carthage, 2Kopp Veterinary Consulting, St Louis, 3Clarkson-Wilson Veterinary Clinic, Chesterfield, 4Mackenzie Pointe Animal Hospital, St Louis, 5Midwest Veterinary Referral Center, Chesterfield, MO, USA Introduction: Sub-optimal joint function is extremely prevalent in dogs. Therefore, a 6-week, prospective, randomized, double-blind, placebo-controlled study was conducted at eight different veterinary clinics to evaluate the efficacy, safety, and tolerability of NEM® brand eggshell membrane (EM, a novel dietary supplement shown in other species to help maintain healthy joints and connective tissues. Subjects and methods: Fifty-one dogs received oral EM ~13.5 mg/kg (6 mg/lb or placebo (excipients once daily for six weeks. The primary outcome measure of this study was to evaluate the change in mean joint function following 1 week and 6 weeks of supplementation as determined via the Canine Brief Pain Inventory (CBPI questionnaire (Q#5-10 in the treatment group versus the placebo group. Secondary outcome measures were for changes in mean CBPI pain and CBPI quality of life, and mean joint pain, mobility and lameness via Veterinary Canine Scoring Assessments (VCSA. A final secondary outcome measure was for a change in serum levels of the cartilage degradation biomarker, c-terminal cross-linked telopeptide of type-II collagen (CTX-II. Results: Supplementation with EM produced a significant treatment response versus placebo at 1 week (20.5% improvement, P=0.028, but fell shy of significance at 6 weeks post-treatment (22.5% improvement for the primary outcome measure (CBPI Function, despite a sizeable treatment effect. Similarly, there was also a significant treatment response versus placebo at 1 week for CBPI Pain (19.4% improvement, P=0.010, but fell just shy of significance at 6 weeks (22.5% improvement, again despite a sizeable

  10. The Role of Healthy Lifestyle in the Implementation of Regressing Suboptimal Health Status among College Students in China: A Nested Case-Control Study

    Directory of Open Access Journals (Sweden)

    Jieyu Chen

    2017-02-01

    Full Text Available Background: Suboptimal health status (SHS is the intermediate health state between health and disease, it is medically undiagnosed and is also termed functional somatic syndrome. Although its clinical manifestations are complicated and various, SHS has not reached the disease status. Unhealthy lifestyle is associated with many chronic diseases and mortality. In accordance with the impact of lifestyle on health, it is intriguing to determine the association between unhealthy lifestyle and SHS risk. Methods: We conducted a nested case-control study among healthy Chinese college students from March 2012 to September 2013, which was nested in a prospective cohort of 5676 students. We performed 1:1 incidence density sampling with matched controls for birth year, sex, grade, specialty and individual character. SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0. Exposure was defined as an unhealthy lifestyle per the frequency of six behavioral dimensions from the Health-promoting Lifestyle Profile (HPLP-II. Results: We matched 543 cases of SHS (42.66% in a cohort of 1273 students during the 1.5 years mean follow-up time with controls. A significant difference (t = 9.79, p < 0.001 and a reduction in HPLP-II total score was present at 1.5 years follow-up (135.93 ± 17.65 compared to baseline (144.48 ± 18.66. A level-response effect was recorded with an increase of the total HPLP-II (every dimension was correlated with a decreased SHS risk. Compared to respondents with the least exposure (excellent level, those reporting a general HPLP-II level were approximately 2.3 times more likely to develop SHS (odd ratio = 2.333, 95% CI = 1.471 to 3.700; and those with less HPLP-II level (good level were approximately 1.6 times more likely (1.644, 1.119–2.414 to develop SHS (p < 0.05. Our data indicated that unhealthy lifestyle behavior with respect to behavioral dimensions significantly affected SHS likelihood

  11. EPA's Benchmark Dose Modeling Software

    Science.gov (United States)

    The EPA developed the Benchmark Dose Software (BMDS) as a tool to help Agency risk assessors facilitate applying benchmark dose (BMD) method’s to EPA’s human health risk assessment (HHRA) documents. The application of BMD methods overcomes many well know limitations ...

  12. Dose calculation of anticancer drugs

    NARCIS (Netherlands)

    Gao, Bo; Klumpen, Heinz-Josef; Gurney, Howard

    2008-01-01

    BACKGROUND: Anticancer drugs are characterized by a narrow therapeutic window and significant inter-patient variability in therapeutic and toxic effects. Current body surface area (BSA)-based dosing fails to standardize systemic anticancer drug exposure and other alternative dosing strategies also

  13. Evolution of radon dose evaluation

    Directory of Open Access Journals (Sweden)

    Fujimoto Kenzo

    2004-01-01

    Full Text Available The historical change of radon dose evaluation is reviewed based on the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR reports. Since 1955, radon has been recognized as one of the important sources of exposure of the general public. However, it was not really understood that radon is the largest dose contributor until 1977 when a new concept of effective dose equivalent was introduced by International Commission on Radiological Protection. In 1982, the dose concept was also adapted by UNSCEAR and evaluated per caput dose from natural radiation. Many researches have been carried out since then. However, lots of questions have remained open in radon problems, such as the radiation weighting factor of 20 for alpha rays and the large discrepancy of risk estimation among dosimetric and epidemiological approaches.

  14. Sequential chemoimmunotherapy of experimental visceral leishmaniasis using a single low dose of liposomal amphotericin B and a novel DNA vaccine candidate.

    Science.gov (United States)

    Seifert, Karin; Juhls, Christiane; Salguero, Francisco J; Croft, Simon L

    2015-09-01

    Combination therapies for leishmaniasis, including drugs and immunomodulators, are one approach to shorten treatment courses and to improve the treatment of complex manifestations of the disease. We evaluated a novel T-cell-epitope-enriched DNA vaccine candidate (LEISHDNAVAX) as host-directed immunotherapy in combination with a standard antileishmanial drug in experimental visceral leishmaniasis. Here we show that the DNA vaccine candidate can boost the efficacy of a single suboptimal dose of liposomal amphotericin B in C57BL/6 mice. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. Low-Dose Bone Morphogenetic Protein-2/Stromal Cell-Derived Factor-1β Cotherapy Induces Bone Regeneration in Critical-Size Rat Calvarial Defects

    Science.gov (United States)

    Herberg, Samuel; Susin, Cristiano; Pelaez, Manuel; Howie, R. Nicole; Moreno de Freitas, Rubens; Lee, Jaebum; Cray, James J.; Johnson, Maribeth H.; Elsalanty, Mohammed E.; Hamrick, Mark W.; Isales, Carlos M.; Wikesjö, Ulf M.E.

    2014-01-01

    Increasing evidence suggests that stromal cell-derived factor-1 (SDF-1/CXCL12) is involved in bone formation, though underlying molecular mechanisms remain to be fully elucidated. Also, contributions of SDF-1β, the second most abundant splice variant, as an osteogenic mediator remain obscure. We have shown that SDF-1β enhances osteogenesis by regulating bone morphogenetic protein-2 (BMP-2) signaling in vitro. Here we investigate the dose-dependent contribution of SDF-1β to suboptimal BMP-2-induced local bone formation; that is, a dose that alone would be too low to significantly induce bone formation. We utilized a critical-size rat calvarial defect model and tested the hypotheses that SDF-1β potentiates BMP-2 osteoinduction and that blocking SDF-1 signaling reduces the osteogenic potential of BMP-2 in vivo. In preliminary studies, radiographic analysis at 4 weeks postsurgery revealed a dose-dependent relationship in BMP-2-induced new bone formation. We then found that codelivery of SDF-1β potentiates suboptimal BMP-2 (0.5 μg) osteoinduction in a dose-dependent order, reaching comparable levels to the optimal BMP-2 dose (5.0 μg) without apparent adverse effects. Blocking the CXC chemokine receptor 4 (CXCR4)/SDF-1 signaling axis using AMD3100 attenuated the osteoinductive potential of the optimal BMP-2 dose, confirmed by qualitative histologic analysis. In conclusion, SDF-1β provides potent synergistic effects that support BMP-induced local bone formation and thus appears a suitable candidate for optimization of bone augmentation using significantly lower amounts of BMP-2 in spine, orthopedic, and craniofacial settings. PMID:24341891

  16. Homocysteine is a novel risk factor for suboptimal response of blood platelets to acetylsalicylic acid in coronary artery disease: a randomized multicenter study.

    Science.gov (United States)

    Karolczak, Kamil; Kamysz, Wojciech; Karafova, Anna; Drzewoski, Jozef; Watala, Cezary

    2013-08-01

    The incomplete inhibition of platelet function by acetylsalicylic acid (ASA), despite the patients are receiving therapeutic doses of the drug ('aspirin-resistance'), is caused by numbers of risk factors. In this study we verified the idea that plasma homocysteine (Hcy) contributes to 'aspirin-resistance' in patients with coronary artery disease (CAD) and with or without type 2 diabetes mellitus (T2DM). A cross-designed randomized controlled intervention study has been performed (126 CAD pts incl. 26 with T2DM) to determine whether increasing ASA dose from 75mg to 150mg daily may result in the increased antiplatelet effect, in the course of four-week treatment. Platelet response to collagen (coll) or arachidonic acid (AA) was monitored with whole blood aggregometry, plasma thromboxane (Tx), and Hcy levels were determined immunochemically. The ASA-mediated reductions in platelet response to coll (by 12±3%) or AA (by 10±3%) and in plasma Tx (by 20±9%; pproperties of ASA therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Radiation dose estimates for radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Stabin, M.G.; Stubbs, J.B.; Toohey, R.E. [Oak Ridge Inst. of Science and Education, TN (United States). Radiation Internal Dose Information Center

    1996-04-01

    Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms.

  18. Superficial dose evaluation of four dose calculation algorithms

    Science.gov (United States)

    Cao, Ying; Yang, Xiaoyu; Yang, Zhen; Qiu, Xiaoping; Lv, Zhiping; Lei, Mingjun; Liu, Gui; Zhang, Zijian; Hu, Yongmei

    2017-08-01

    Accurate superficial dose calculation is of major importance because of the skin toxicity in radiotherapy, especially within the initial 2 mm depth being considered more clinically relevant. The aim of this study is to evaluate superficial dose calculation accuracy of four commonly used algorithms in commercially available treatment planning systems (TPS) by Monte Carlo (MC) simulation and film measurements. The superficial dose in a simple geometrical phantom with size of 30 cm×30 cm×30 cm was calculated by PBC (Pencil Beam Convolution), AAA (Analytical Anisotropic Algorithm), AXB (Acuros XB) in Eclipse system and CCC (Collapsed Cone Convolution) in Raystation system under the conditions of source to surface distance (SSD) of 100 cm and field size (FS) of 10×10 cm2. EGSnrc (BEAMnrc/DOSXYZnrc) program was performed to simulate the central axis dose distribution of Varian Trilogy accelerator, combined with measurements of superficial dose distribution by an extrapolation method of multilayer radiochromic films, to estimate the dose calculation accuracy of four algorithms in the superficial region which was recommended in detail by the ICRU (International Commission on Radiation Units and Measurement) and the ICRP (International Commission on Radiological Protection). In superficial region, good agreement was achieved between MC simulation and film extrapolation method, with the mean differences less than 1%, 2% and 5% for 0°, 30° and 60°, respectively. The relative skin dose errors were 0.84%, 1.88% and 3.90%; the mean dose discrepancies (0°, 30° and 60°) between each of four algorithms and MC simulation were (2.41±1.55%, 3.11±2.40%, and 1.53±1.05%), (3.09±3.00%, 3.10±3.01%, and 3.77±3.59%), (3.16±1.50%, 8.70±2.84%, and 18.20±4.10%) and (14.45±4.66%, 10.74±4.54%, and 3.34±3.26%) for AXB, CCC, AAA and PBC respectively. Monte Carlo simulation verified the feasibility of the superficial dose measurements by multilayer Gafchromic films. And the rank

  19. Effects of low doses; Effet des faibles doses

    Energy Technology Data Exchange (ETDEWEB)

    Le Guen, B. [Electricite de France (EDF-LAM-SCAST), 93 - Saint-Denis (France)

    2001-07-01

    Actually, even though it is comfortable for the risk management, the hypothesis of the dose-effect relationship linearity is not confirmed for any model. In particular, in the area of low dose rate delivered by low let emitters. this hypothesis is debated at the light of recent observations, notably these ones relative to the mechanisms leading to genetic instability and induction eventuality of DNA repair. The problem of strong let emitters is still to solve. (N.C.)

  20. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    Finch, S.M.; McMakin, A.H. (comps.)

    1991-01-01

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon and Washington, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on human (dose estimates): Source Terms; Environmental Transport; Environmental Monitoring Data; Demographics, Agriculture, Food Habits and; Environmental Pathways and Dose Estimates.

  1. Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    McMakin, A.H.; Cannon, S.D.; Finch, S.M. (comps.)

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

  2. Minimal Erythema Dose (MED) testing.

    Science.gov (United States)

    Heckman, Carolyn J; Chandler, Rachel; Kloss, Jacqueline D; Benson, Amy; Rooney, Deborah; Munshi, Teja; Darlow, Susan D; Perlis, Clifford; Manne, Sharon L; Oslin, David W

    2013-05-28

    Ultraviolet radiation (UV) therapy is sometimes used as a treatment for various common skin conditions, including psoriasis, acne, and eczema. The dosage of UV light is prescribed according to an individual's skin sensitivity. Thus, to establish the proper dosage of UV light to administer to a patient, the patient is sometimes screened to determine a minimal erythema dose (MED), which is the amount of UV radiation that will produce minimal erythema (sunburn or redness caused by engorgement of capillaries) of an individual's skin within a few hours following exposure. This article describes how to conduct minimal erythema dose (MED) testing. There is currently no easy way to determine an appropriate UV dose for clinical or research purposes without conducting formal MED testing, requiring observation hours after testing, or informal trial and error testing with the risks of under- or over-dosing. However, some alternative methods are discussed.

  3. High dose irradiation with hyperfractionation

    Energy Technology Data Exchange (ETDEWEB)

    Asakura, Hideo; Kurashima, Shoji; Hasegawa, Maki; Akiyama, Kazuo (Sagamihara National Hospital, Kanagawa (Japan))

    1990-10-01

    From March 1988 to January 1990, 12 patients including 7 primary lung cancers, 2 lung metastases of colorectal cancer, and each 1 gall bladder cancer, ovarian cancer, and spinal cord metastasis of prostatic cancer, received {sup 60}Co-irradiation with high dose by hyperfractionation. This hyperfractionation consisted of 1.2 Gy per fraction, twice a day with 6 hour interval, and 5 days (10 fractions) a week. The total dose administered was 81.6{approx}100 Gy. The acute reaction of skin, lung, and intestines was tolerable, and it seemed that the late damage of normal tissues was slighter and the treatment result was favorable in comparison with the conventional fractionation, but this estimation was not definite because of short observation period. It was discussed that further reduction of dose per fraction (1 Gy or below) and more increased total dose (100 Gy or more) would be promising in hyperfractionation. (author).

  4. The dose makes the medicine.

    Science.gov (United States)

    Stumpf, Walter E

    2006-06-01

    Dose and time considerations in the development and use of a drug are important for assessing actions and side effects, as well as predictions of safety and toxicity. This article deals with epistemological aspects of dose selection by probing into the linguistic and cultural roots for the measure of medicine mediated by the medical doctor. Because toxicity is related to dose, historic and recent views suggest that less can be more. At low, medium and high dose levels, effects can differ not only quantitatively but also qualitatively. Dose-related target activation and recognition of enantiodromic thresholds between beneficial and toxic effects require elucidation of underlying events. Such studies, including hormesis and microdosing, call for extended ADME procedures with high-resolution methods in addition to the current low-resolution approaches. Improved information of drug logistics and target pharmacokinetics enables effective drug selection, dose determination and prediction. It also allows considerations of systems biology [i.e. integral (gestalt) pharmacology] exemplified by the drug homunculus, as in the case of vitamin D, that might lead to new paradigms and drug design.

  5. BENCHMARK DOSE TECHNICAL GUIDANCE DOCUMENT ...

    Science.gov (United States)

    The U.S. EPA conducts risk assessments for an array of health effects that may result from exposure to environmental agents, and that require an analysis of the relationship between exposure and health-related outcomes. The dose-response assessment is essentially a two-step process, the first being the definition of a point of departure (POD), and the second extrapolation from the POD to low environmentally-relevant exposure levels. The benchmark dose (BMD) approach provides a more quantitative alternative to the first step in the dose-response assessment than the current NOAEL/LOAEL process for noncancer health effects, and is similar to that for determining the POD proposed for cancer endpoints. As the Agency moves toward harmonization of approaches for human health risk assessment, the dichotomy between cancer and noncancer health effects is being replaced by consideration of mode of action and whether the effects of concern are likely to be linear or nonlinear at low doses. Thus, the purpose of this project is to provide guidance for the Agency and the outside community on the application of the BMD approach in determining the POD for all types of health effects data, whether a linear or nonlinear low dose extrapolation is used. A guidance document is being developed under the auspices of EPA's Risk Assessment Forum. The purpose of this project is to provide guidance for the Agency and the outside community on the application of the benchmark dose (BMD) appr

  6. Weldon Spring historical dose estimate

    Energy Technology Data Exchange (ETDEWEB)

    Meshkov, N.; Benioff, P.; Wang, J.; Yuan, Y.

    1986-07-01

    This study was conducted to determine the estimated radiation doses that individuals in five nearby population groups and the general population in the surrounding area may have received as a consequence of activities at a uranium processing plant in Weldon Spring, Missouri. The study is retrospective and encompasses plant operations (1957-1966), cleanup (1967-1969), and maintenance (1969-1982). The dose estimates for members of the nearby population groups are as follows. Of the three periods considered, the largest doses to the general population in the surrounding area would have occurred during the plant operations period (1957-1966). Dose estimates for the cleanup (1967-1969) and maintenance (1969-1982) periods are negligible in comparison. Based on the monitoring data, if there was a person residing continually in a dwelling 1.2 km (0.75 mi) north of the plant, this person is estimated to have received an average of about 96 mrem/yr (ranging from 50 to 160 mrem/yr) above background during plant operations, whereas the dose to a nearby resident during later years is estimated to have been about 0.4 mrem/yr during cleanup and about 0.2 mrem/yr during the maintenance period. These values may be compared with the background dose in Missouri of 120 mrem/yr.

  7. Model Informed Dose Optimization of Dichloroacetate for the Treatment of Congenital Lactic Acidosis in Children.

    Science.gov (United States)

    Mangal, Naveen; James, Margaret O; Stacpoole, Peter W; Schmidt, Stephan

    2017-09-15

    Dichloroacetate (DCA) is an investigational drug used to treat congenital lactic acidosis and other mitochondrial disorders. Response to DCA therapy in young children may be suboptimal following body weight-based dosing. This is because of autoinhibition of its metabolism, age-dependent changes in pharmacokinetics, and polymorphisms in glutathione transferase zeta 1 (GSTZ1), its primary metabolizing enzyme. Our objective was to predict optimal DCA doses for the treatment of congenital lactic acidosis in children. Accordingly, a semimechanistic pharmacokinetic-enzyme turnover model was developed in a step-wise approach: (1) a population pharmacokinetic model for adults was developed; (2) the adult model was scaled to children using allometry and physiology-based scaling; and (3) the scaled model was externally qualified, updated with clinical data, and optimal doses were projected. A 2-compartment model accounting for saturable clearance and GSTZ1 enzyme turnover successfully characterized the DCA PK in adults and children. DCA-induced inactivation of GSTZ1 resulted in phenoconversion of all subjects into slow metabolizers after repeated dosing. However, rate and extent of inactivation was 2-fold higher in subjects without the wild-type EGT allelic variant of GSTZ1, resulting in further phenoconversion into ultraslow metabolizers after repeated DCA administration. Furthermore, DCA-induced GSTZ1 inactivation rate and extent was found to be 25- to 30-fold lower in children than in adults, potentially accounting for the observed age-dependent changes in PK. Finally, a 12.5 and 10.6 mg/kg twice-daily DCA dose was optimal in achieving the target steady-state trough concentrations (5-25 mg/L) for EGT carrier and EGT noncarrier children, respectively. © 2017, The American College of Clinical Pharmacology.

  8. Isobio software: biological dose distribution and biological dose volume histogram from physical dose conversion using linear-quadratic-linear model

    National Research Council Canada - National Science Library

    Tanwiwat Jaikuna; Phatchareewan Khadsiri; Nisa Chawapun; Suwit Saekho; Ekkasit Tharavichitkul

    2017-01-01

      Purpose: To develop an in-house software program that is able to calculate and generate the biological dose distribution and biological dose volume histogram by physical dose conversion using the linear-quadratic-linear (LQL) model...

  9. Dose assessments for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Avila, Rodolfo; Ekstroem, Per-Anders; Cruz, Idalmis de la (Facilia AB, Bromma (Sweden))

    2008-06-15

    Following a review by the Swedish regulatory authorities of the safety analysis of the SFR 1 disposal facility for low and intermediate level waste, SKB has prepared an updated safety analysis, SAR-08. This report presents estimations of annual doses to the most exposed groups from potential radionuclide releases from the SFR 1 repository for a number of calculation cases, selected using a systematic approach for identifying relevant scenarios for the safety analysis. The dose estimates can be used for demonstrating that the long term safety of the repository is in compliance with the regulatory requirements. In particular, the mean values of the annual doses can be used to estimate the expected risks to the most exposed individuals, which can then be compared with the regulatory risk criteria for human health. The conversion from doses to risks is performed in the main report. For one scenario however, where the effects of an earthquake taking place close to the repository are analysed, risk calculations are presented in this report. In addition, prediction of concentrations of radionuclides in environmental media, such as water and soil, are compared with concentration limits suggested by the Erica-project as a base for estimating potential effects on the environment. The assessment of the impact on non-human biota showed that the potential impact is negligible. Committed collective dose for an integration period of 10,000 years for releases occurring during the first thousand years after closure are also calculated. The collective dose commitment was estimated to be 8 manSv. The dose calculations were carried out for a period of 100,000 years, which was sufficient to observe peak doses in all scenarios considered. Releases to the landscape and to a well were considered. The peaks of the mean annual doses from releases to the landscape are associated with C-14 releases to a future lake around year 5,000 AD. In the case of releases to a well, the peak annual doses

  10. Applications of sub-optimality in dynamic programming to location and construction of nuclear fuel processing plant; Application de la sous-optimalite en programmation dynamique a la localisation et la cadence optimales de construction des equipements

    Energy Technology Data Exchange (ETDEWEB)

    Thiriet, L.; Deledicq, A. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires, section des etudes economiques generales

    1968-09-01

    First, the point of applying Dynamic Programming to optimization and Operational Research problems in chemical industries are recalled, as well as the conditions in which a dynamic program is illustrated by a sequential graph. A new algorithm for the determination of sub-optimal politics in a sequential graph is then developed. Finally, the applications of sub-optimality concept is shown when taking into account the indirect effects related to possible strategies, or in the case of stochastic choices and of problems of the siting of plants... application examples are given. (authors) [French] On rappelle d'abord l'interet de la Programmation Dynamique dans les problemes d'optimisation et de Recherche Operationnelle dans les industries chimiques, et les conditions de representation d'un programme dynamique par un graphe sequentiel. On expose ensuite un nouvel algorithme de determination de politiques sous-optimales dans un graphe sequentiel. On montre enfin les applications du concept de sous-optimalite a la prise en compte d'effets indirects lies aux politiques possibles, aux choix dans l'aleatoire, a des problemes de localisation optimale d'usines... et on donne des exemples d'utilisation. (auteurs)

  11. Radiation dose monitoring in the clinical routine

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika [UK Essen (Germany). Radiology

    2017-04-15

    Here we describe the first clinical experiences regarding the use of an automated radiation dose management software to monitor the radiation dose of patients during routine examinations. Many software solutions for monitoring radiation dose have emerged in the last decade. The continuous progress in radiological techniques, new scan features, scanner generations and protocols are the primary challenge for radiation dose monitoring software systems. To simulate valid dose calculations, radiation dose monitoring systems have to follow current trends and stay constantly up-to-date. The dose management software is connected to all devices at our institute and conducts automatic data acquisition and radiation dose calculation. The system incorporates 18 virtual phantoms based on the Cristy phantom family, estimating doses in newborns to adults. Dose calculation relies on a Monte Carlo simulation engine. Our first practical experiences demonstrate that the software is capable of dose estimation in the clinical routine. Its implementation and use have some limitations that can be overcome. The software is promising and allows assessment of radiation doses, like organ and effective doses according to ICRP 60 and ICRP 103, patient radiation dose history and cumulative radiation doses. Furthermore, we are able to determine local diagnostic reference doses. The radiation dose monitoring software systems can facilitate networking between hospitals and radiological departments, thus refining radiation doses and implementing reference doses at substantially lower levels.

  12. Fluzone High-Dose Seasonal Influenza Vaccine

    Science.gov (United States)

    ... Variant Pandemic Other Fluzone High-Dose Seasonal Influenza Vaccine Questions & Answers Language: English (US) Español Recommend on ... flu season. What is Fluzone High-Dose influenza vaccine? Fluzone High-Dose is an influenza vaccine, manufactured ...

  13. Radiological dose assessment for vault storage concepts

    Energy Technology Data Exchange (ETDEWEB)

    Richard, R.F.

    1997-02-25

    This radiological dose assessment presents neutron and photon dose rates in support of project W-460. Dose rates are provided for a single 3013 container, the ``infloor`` storage vault concept, and the ``cubicle`` storage vault concept.

  14. AGING FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    R.L. Thacker

    2005-03-24

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Aging Facility performing operations to transfer aging casks to the aging pads for thermal and logistical management, stage empty aging casks, and retrieve aging casks from the aging pads for further processing in other site facilities. Doses received by workers due to aging cask surveillance and maintenance operations are also included. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation. There are no Category 1 event sequences associated with the Aging Facility (BSC 2004 [DIRS 167268], Section 7.2.1). The results of this calculation will be used to support the design of the Aging Facility and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in Environmental and Nuclear Engineering.

  15. Improving antibiotic dosing in special situations in the ICU: burns, renal replacement therapy and extracorporeal membrane oxygenation.

    Science.gov (United States)

    Jamal, Janattul-Ain; Economou, Caleb J P; Lipman, Jeffrey; Roberts, Jason A

    2012-10-01

    Antibiotic dosing for critically ill patients that is derived from other patient groups is likely to be suboptimal because of significant antibiotic pharmacokinetic changes, particularly in terms of drug volume of distribution and clearance. Organ support techniques including renal replacement therapy (RRT) and extracorporeal membrane oxygenation (ECMO) increase the pharmacokinetic variability. This article reviews the recently published antibiotic pharmacokinetic data associated with burns patients, those receiving continuous RRT (CRRT), sustained low-efficiency dialysis (SLED) and ECMO. These groups develop increases in volume of distribution that necessitate the use of higher initial doses to rapidly achieve therapeutic antibiotic concentrations. Burns patients have supranormal drug clearances requiring more frequent administration of antibiotics. Patients receiving CRRT or SLED have variable drug clearances related to different equipment and RRT settings at different institutions. ECMO presents a different challenge because there is such a dearth of data with higher than standard doses potentially required, even in the presence of end-organ failure. In the context of such variable pharmacokinetics, a guideline approach to dosing remains elusive because of insufficient available data and, therefore, use of therapeutic drug monitoring should be considered advantageous where possible.

  16. Efficacy of single-dose ceftriaxone in experimental otitis media induced by penicillin- and cephalosporin-resistant Streptococcus pneumoniae.

    Science.gov (United States)

    Barry, B; Muffat-Joly, M; Bauchet, J; Faurisson, F; Gehanno, P; Pocidalo, J J; Carbon, C

    1996-09-01

    We used a gerbil model of otitis media to assess the efficacy of single-dose ceftriaxone against three Streptococcus pneumoniae strains highly resistant to penicillin (MICs, 4 to 8 micrograms/ml) and with various susceptibilities to ceftriaxone (MICs, 0.5, 4, and 8 micrograms/ml). Middle ear infection was induced by bilateral transbullar challenge with 10(7) bacteria per ear. Antibiotic treatment was administered subcutaneously at 2 h postinfection. Infection status was checked 2 days later by counting the bacteria in middle ear and cerebrospinal fluid samples. With the cefriaxone-susceptible strain (MIC, 0.5 microgram/ml), we tested doses of 5 to 100 mg/kg of body weight. With a dose of 50 mg/kg, treatment outcome was equivalent to that with amoxicillin, which was used as a reference (25 mg/kg, two injections); no bacteria were recovered from 82% of the middle ear samples, and the rate of cerebrospinal fluid culture positivity was significantly reduced to 6%, relative to 59% for the untreated controls. Similar efficacy was obtained with a dose of 100 mg/kg against the two ceftriaxone-resistant strains. Pharmacokinetic study indicates that the values of the parameters in plasma after the administration of a dose of 100 mg/kg (peak level of total drug, 268 +/- 33 micrograms/ml; elimination half-life, 0.8 h; area under concentration-time curve, 488 micrograms.h.ml-1) were still suboptimal compared with the values of the parameters measured in pediatric patients after intravenous or intramuscular administration of a dose of 50 mg/kg. Our results indicate the efficacy of ceftriaxone against experimental cephalosporin-resistant pneumococcal otitis and provide a basis for the clinical use of single-dose ceftriaxone against pneumococcal otitis media.

  17. Do dose area product meter measurements reflect radiation doses ...

    African Journals Online (AJOL)

    Enrique

    accurately measures the radiation emitted from the source. The study included the interventional radiolo ... mined as most sensitive to radiation. The use of a thyroid guard also decreases the effective dose by approx- ... al radiation is necessary. Thermo- luminescent dosimetry is used to measure radiation and the apparatus.

  18. Performance standard for dose Calibrator

    CERN Document Server

    Darmawati, S

    2002-01-01

    Dose calibrator is an instrument used in hospitals to determine the activity of radionuclide for nuclear medicine purposes. International Electrotechnical Commission (IEC) has published IEC 1303:1994 standard that can be used as guidance to test the performance of the instrument. This paper briefly describes content of the document,as well as explains the assessment that had been carried out to test the instrument accuracy in Indonesia through intercomparison measurement.Its is suggested that hospitals acquire a medical physicist to perform the test for its dose calibrator. The need for performance standard in the form of Indonesia Standard is also touched.

  19. Routine High Dose Excretory Urography

    Science.gov (United States)

    Gronner, Arthur T.; Arkoff, Robert S.; Burhenne, H. Joachim

    1967-01-01

    Radiologic evaluation of 316 excretory urograms utilizing a single 50 ml injection of a 50 to 60 per cent tri-iodinated contrast medium indicated that these studies are of better quality than those previously obtained with the injection of 30 ml. The low incidence of side effects coincides with recent reports in the literature that this dosage level is safe. High dose intravenous drip infusion pyelography was necessary only in selected cases. High dose excretory urography is recommended for routine use. ImagesFigure 1A, 1BFigure 2. PMID:6045483

  20. Confectionery-based dose forms.

    Science.gov (United States)

    Tangso, Kristian J; Ho, Quy Phuong; Boyd, Ben J

    2015-01-01

    Conventional dosage forms such as tablets, capsules and syrups are prescribed in the normal course of practice. However, concerns about patient preferences and market demands have given rise to the exploration of novel unconventional dosage forms. Among these, confectionery-based dose forms have strong potential to overcome compliance problems. This report will review the availability of these unconventional dose forms used in treating the oral cavity and for systemic drug delivery, with a focus on medicated chewing gums, medicated lollipops, and oral bioadhesive devices. The aim is to stimulate increased interest in the opportunities for innovative new products that are available to formulators in this field, particularly for atypical patient populations.

  1. Radiation dose escalation for loco-regional recurrence of breast cancer after mastectomy

    Directory of Open Access Journals (Sweden)

    Skinner Heath D

    2013-01-01

    Full Text Available Abstract Background Radiation is a standard component of treatment for patients with locoregional recurrence (LRR of breast cancer following mastectomy. The current study reports the results of a 10% radiation dose escalation in these patients. Methods 159 patients treated at MD Anderson Cancer Center between 1994-2006 with isolated LRR after mastectomy alone were reviewed. Patients in the standard treatment group (65 pts, 40.9% were treated to 50 Gy comprehensively plus a boost of 10 Gy. The dose escalated group (94 pts, 59.1% was treated to 54 Gy comprehensively and a minimum 12 Gy boost. Median dose in the standard dose and dose escalated group was 60 Gy (±1 Gy, 95% CI and 66 Gy (±0.5 Gy, 95% CI respectively. Median follow up for living patients was 94 months from time of recurrence. Results The actuarial five year locoregional control (LRC rate was 77% for the entire study population. The five year overall survival and disease-free survival was 55% and 41%, respectively. On multivariate analysis, initial tumor size (p = 0.03, time to initial LRR (p = 0.03, absence of gross tumor at the time of radiation (p = 0.001 and Her2 status (p = 0.03 were associated with improved LRC. Five year LRC rates were similar in patients with a complete response to chemotherapy without surgery and patients with a complete surgical excision (77% vs 83%, p = NS, compared to a 63% LRC rate in patients with gross disease at the time of radiation (p = 0.024. LRC rates were 80% in the standard dose group and 75% in the dose escalated group (p = NS. Conclusions While LRR following mastectomy is potentially curable, distant metastasis and local control rates remain suboptimal. Radiation dose escalation did not appear to improve LRC. Given significant local failure rates, these patients are good candidates for additional strategies to improve their outcomes.

  2. Proton-Pump Inhibitors Reduce Gastrointestinal Events Regardless of Aspirin Dose in Patients Requiring Dual Antiplatelet Therapy.

    Science.gov (United States)

    Vaduganathan, Muthiah; Bhatt, Deepak L; Cryer, Byron L; Liu, Yuyin; Hsieh, Wen-Hua; Doros, Gheorghe; Cohen, Marc; Lanas, Angel; Schnitzer, Thomas J; Shook, Thomas L; Lapuerta, Pablo; Goldsmith, Mark A; Laine, Loren; Cannon, Christopher P

    2016-04-12

    The COGENT (Clopidogrel and the Optimization of Gastrointestinal Events Trial) showed that proton-pump inhibitors (PPIs) safely reduced rates of gastrointestinal (GI) events in patients requiring dual antiplatelet therapy (DAPT). However, utilization of appropriate prophylactic PPI therapy remains suboptimal, especially with low-dose aspirin. The authors investigated the safety and efficacy of PPI therapy in patients receiving DAPT in low- and high-dose aspirin subsets. Randomized patients with available aspirin dosing information in COGENT (N = 3,752) were divided into "low-dose" (≤ 100 mg) and "high-dose" (>100 mg) aspirin groups. The primary GI and cardiovascular endpoints were composite upper GI events and major adverse cardiac events, respectively. All events were adjudicated by independent, blinded gastroenterologists and cardiologists. Median duration of follow-up was 110 days. Low-dose aspirin users (n = 2,480; 66.1%) were more likely to be older, female, and have higher rates of peripheral artery disease, prior stroke, and hypertension, whereas high-dose aspirin users (n = 1,272; 33.9%) had higher rates of hyperlipidemia, smoking, a history of percutaneous coronary intervention, and were more than twice as likely to be enrolled from sites within the United States (80.4% vs. 39.8%). High-dose aspirin was associated with similar 180-day Kaplan-Meier estimates of adjudicated composite GI events (1.7% vs. 2.1%; adjusted hazard ratio: 0.88; 95% confidence interval: 0.46 to 1.66) and major adverse cardiac events (4.8% vs. 5.5%; adjusted hazard ratio: 0.73; 95% confidence interval: 0.48 to 1.11) compared with low-dose aspirin. Randomization to PPI therapy reduced 180-day Kaplan-Meier estimates of the primary GI endpoint in low-dose (1.2% vs. 3.1%) and high-dose aspirin subsets (0.9% vs. 2.6%; p for interaction = 0.80), and did not adversely affect the primary cardiovascular endpoint in either group. Gastroprotection with PPI therapy should be utilized in

  3. Resurgence of Colistin: A Review of Resistance, Toxicity, Pharmacodynamics, and Dosing

    Science.gov (United States)

    Lim, Lauren M.; Ly, Neang; Anderson, Dana; Yang, Jenny C.; Macander, Laurie; Jarkowski, Anthony; Forrest, Alan; Bulitta, Jurgen B.; Tsuji, Brian T.

    2011-01-01

    Colistin is a polymyxin antibiotic that was discovered in the late 1940s for the treatment of gram-negative infections. After several years of clinical use, its popularity diminished because of reports of significant nephrotoxicity and neurotoxicity. Recently, the antibiotic has resurfaced as a last-line treatment option for multidrug-resistant organisms such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae. The need for antibiotics with coverage of these gram-negative pathogens is critical because of their high morbidity and mortality, making colistin a very important treatment option. Unfortunately, however, resistance to colistin has been documented among all three of these organisms in case reports. Although the exact mechanism causing colistin resistance has not been defined, it is hypothesized that the PmrA-PmrB and PhoP-PhoQ genetic regulatory systems may play a role. Colistin dosages must be optimized, as colistin is a last-line treatment option; in addition, suboptimal doses have been linked to the development of resistance. The lack of pharmacokinetic and pharmacodynamic studies and no universal harmonization of dose units, however, have made it difficult to derive optimal dosing regimens and specific dosing guidelines for colistin. In critically ill patients who may have multiorgan failure, renal insufficiency may alter colistin pharmacokinetics. Therefore, dosage alterations in this patient population are imperative to achieve maximal efficacy and minimal toxicity. With regard to colistin toxicity, most studies show that nephrotoxicity is reversible and less frequent than once thought, and neurotoxicity is rare. Further research is needed to fully understand the impact that the two regulatory systems have on resistance, as well as the dosages of colistin needed to inhibit and overcome these developing patterns. PMID:21114395

  4. Postoperative radiotherapy dose correlates with locoregional control in patients with extra-hepatic bile duct cancer

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jung Ho; Seong, Jinsil; Lee, Jeong Shim; Kim, Yong Bae; Kim, Kyung Sik; Lee, Woo Jung [Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, Ik Jae; Park, Jun Sung; Yoon, Dong Sup [Sangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2013-12-15

    To evaluate the results of postoperative radiotherapy in patients with extra-hepatic bile duct cancer (EHBDC) and identify the prognostic factors for local control and survival. Between January 2001 and December 2010, we retrospectively reviewed the cases of 70 patients with EHBDC who had undergone curative resection and received postoperative radiotherapy. The median radiation dose was 50.4 Gy (range, 41.4 to 54 Gy). The resection margin status was R0 in 30 patients (42.9%), R1 in 25 patients (35.7%), and R2 in 15 patients (21.4%). The 5-year rates of overall survival (OS), event-free survival (EFS), and locoregional control (LRC) for all patients were 42.9%, 38.3%, and 61.2%, respectively. The major pattern of failure was distant relapses (33 patients, 47.1%). A multivariate analysis showed that the postradiotherapy CA19-9 level, radiation dose (≥50 Gy), R2 resection margins, perineural invasion, and T stage were the significant prognostic factors for OS, EFS, and LRC. OS was not significantly different between the patients receiving R0 and R1 resections, but was significantly lower among those receiving R2 resection (54.6%, 56.1%, and 7.1% for R0, R1, and R2 resections, respectively). In patients with EHBDC who had undergone curative resection, a postoperative radiotherapy dose less than 50 Gy was suboptimal for OS and LRC. Higher radiation doses may be needed to obtain better LRC. Further investigation of novel therapy or palliative treatment should be considered for patients receiving R2 resection.

  5. Application of PK/PD Modeling in Veterinary Field: Dose Optimization and Drug Resistance Prediction

    Directory of Open Access Journals (Sweden)

    Ijaz Ahmad

    2016-01-01

    Full Text Available Among veterinary drugs, antibiotics are frequently used. The true mean of antibiotic treatment is to administer dose of drug that will have enough high possibility of attaining the preferred curative effect, with adequately low chance of concentration associated toxicity. Rising of antibacterial resistance and lack of novel antibiotic is a global crisis; therefore there is an urgent need to overcome this problem. Inappropriate antibiotic selection, group treatment, and suboptimal dosing are mostly responsible for the mentioned problem. One approach to minimizing the antibacterial resistance is to optimize the dosage regimen. PK/PD model is important realm to be used for that purpose from several years. PK/PD model describes the relationship between drug potency, microorganism exposed to drug, and the effect observed. Proper use of the most modern PK/PD modeling approaches in veterinary medicine can optimize the dosage for patient, which in turn reduce toxicity and reduce the emergence of resistance. The aim of this review is to look at the existing state and application of PK/PD in veterinary medicine based on in vitro, in vivo, healthy, and disease model.

  6. Application of PK/PD Modeling in Veterinary Field: Dose Optimization and Drug Resistance Prediction.

    Science.gov (United States)

    Ahmad, Ijaz; Huang, Lingli; Hao, Haihong; Sanders, Pascal; Yuan, Zonghui

    2016-01-01

    Among veterinary drugs, antibiotics are frequently used. The true mean of antibiotic treatment is to administer dose of drug that will have enough high possibility of attaining the preferred curative effect, with adequately low chance of concentration associated toxicity. Rising of antibacterial resistance and lack of novel antibiotic is a global crisis; therefore there is an urgent need to overcome this problem. Inappropriate antibiotic selection, group treatment, and suboptimal dosing are mostly responsible for the mentioned problem. One approach to minimizing the antibacterial resistance is to optimize the dosage regimen. PK/PD model is important realm to be used for that purpose from several years. PK/PD model describes the relationship between drug potency, microorganism exposed to drug, and the effect observed. Proper use of the most modern PK/PD modeling approaches in veterinary medicine can optimize the dosage for patient, which in turn reduce toxicity and reduce the emergence of resistance. The aim of this review is to look at the existing state and application of PK/PD in veterinary medicine based on in vitro, in vivo, healthy, and disease model.

  7. LOW DOSE INTRAVAGINAL MISOPROSTOL VERSUS ...

    African Journals Online (AJOL)

    hi-tech

    2003-02-02

    Feb 2, 2003 ... for oxytocin augmentation was less in the misoprostol group (RR 0.76, 95% CI 0.64 to 0.91). No significant differences existed in rates for uterine hyperstimulation,. Caesarean section, maternal and neonatal morbidity. Conclusion: Intravaginal misoprostol in a low dose was compared to intracervical balloon.

  8. [Absorbed doses in dental radiology].

    Science.gov (United States)

    Bianchi, S D; Roccuzzo, M; Albrito, F; Ragona, R; Anglesio, S

    1996-01-01

    The growing use of dento-maxillo-facial radiographic examinations has been accompanied by the publication of a large number of studies on dosimetry. A thorough review of the literature is presented in this article. Most studies were carried out on tissue equivalent skull phantoms, while only a few were in vivo. The aim of the present study was to evaluate in vivo absorbed doses during Orthopantomography (OPT). Full Mouth Periapical Examination (FMPE) and Intraoral Tube Panoramic Radiography (ITPR). Measurements were made on 30 patients, reproducing clinical conditions, in 46 anatomical sites, with 24 intra- and 22 extra-oral thermoluminiscent dosimeters (TLDS). The highest doses were measured, in orthopantomography, at the right mandibular angle (1899 mu Gy) in FMPE on the right naso-labial fold (5640 mu Gy and in ITPR on the palatal surface of the left second upper molar (1936 mu Gy). Intraoral doses ranged from 21 mu Gy, in orthopantomography, to 4494 mu Gy in FMPE. Standard errors ranged from 142% in ITPR to 5% in orthopantomography. The highest rate of standard errors was found in FMPE and ITPR. The data collected in this trial are in agreement with others in major literature reports. Disagreements are probably due to different exam acquisition and data collections. Such differences, presented comparison in several sites, justify lower doses in FMPE and ITPR. Advantages and disadvantages of in vivo dosimetry of the maxillary region are discussed, the former being a close resemblance to clinical conditions of examination and the latter the impossibility of collecting values in depth of tissues. Finally, both ITPR and FMPE required lower doses than expected, and can be therefore reconsidered relative to their radiation risk.

  9. Sesame allergy threshold dose distribution.

    Science.gov (United States)

    Dano, D; Remington, B C; Astier, C; Baumert, J L; Kruizinga, A G; Bihain, B E; Taylor, S L; Kanny, G

    2015-09-01

    Sesame is a relevant food allergen in France. Compared to other allergens there is a lack of food challenge data and more data could help sesame allergy risk management. The aim of this study is to collect more sesame challenge data and investigate the most efficient food challenge method for future studies. Records of patients at University Hospital in Nancy (France) with objective symptoms to sesame challenges were collected and combined with previously published data. An estimation of the sesame allergy population threshold was calculated based on individual NOAELs and LOAELs. Clinical dosing schemes at Nancy were investigated to see if the optimal protocol for sesame is currently used. Fourteen patients (10 M/4 F, 22 ± 14.85 years old) with objective symptoms were added to previously published data making a total of 35 sesame allergic patients. The most sensitive patient reacted to the first dose at challenge of 1.02 mg sesame protein. The ED05 ranges between 1.2 and 4.0 mg of sesame protein (Log-Normal, Log-Logistic, and Weibull models) and the ED10 between 4.2 and 6.2 mg. The optimal food challenge dosing scheme for sesame follows semi-log dose increases from 0.3 to 3000 mg protein. This article provides a valuable update to the existing clinical literature regarding sesame NOAELs and LOAELs. Establishment of a population threshold for sesame could help in increasing the credibility of precautionary labelling and decrease the costs associated with unexpected allergic reactions. Also, the use of an optimal dosing scheme would decrease time spent on diagnostic and thereafter on the economic burden of sesame allergy diagnosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Investigations of peripheral dose for helical tomotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lissner, Steffen; Schubert, Kai; Sterzing, Florian; Herfarth, Klaus; Sroka-Perez, Gabriele; Debus, Juergen [University Hospital Heidelberg (Germany). Dept. of Radiation Oncology; Wiezorek, Tilo [University Hospital Jena (Germany). Dept. of Radiotherapy

    2013-07-01

    Purpose: Whenever treating a patient with percutaneous radiotherapy, a certain amount of dose is inevitably delivered to healthy tissue. This is mainly due to beam's entry and exit in the region of the target volume. In regions distant from the target volume, dose is delivered by leakage from the MLC and head scatter from the accelerator head and phantom scatter from the target volume (peripheral dose). Helical tomotherapy is a form of radiation therapy with a uniquely designed machine and delivery pattern which influence the peripheral dose. The goal of this work was to investigate peripheral dose in helical tomotherapy. The experiments were used to establish a complex characterization of the peripheral dose. Materials and methods: A 30*30*60cm{sup 3} slab phantom and TLD-100 (Lithium fluoride) were used for the experiments. Treatment procedures were generated with the tomotherapy planning system (TPS). Additionally, procedures were created on the Operator Station of the tomotherapy system without a calculation of the dose distribution. The peripheral dose which was produced by a typical tomotherapy treatment plan was measured. Furthermore, these procedures were used to differentiate the parts of the peripheral dose in phantom scatter dose and head scatter and leakage dose. Additionally, the relation between peripheral dose and treatment time and between peripheral dose and delivered dose was investigated. Additionally, the peripheral dose was measured in an Alderson phantom. Results: Distances of 30cm or more resulted in a decrease of the peripheral dose to less than 0.1% of the target dose. The measured doses have an offset of approximately 1cGy in comparison to the calculated doses from the TPS. The separated head scatter and leakage dose was measured in the range of 1cGy for typical treatments. Furthermore, the investigations show a linear correlation between head scatter leakage dose and treatment time and between scatter dose parts and delivered dose. A

  11. Combination therapy with sulfasalazine and methotrexate is more effective than either drug alone in patients with rheumatoid arthritis with a suboptimal response to sulfasalazine: results from the double‐blind placebo‐controlled MASCOT study

    Science.gov (United States)

    Capell, Hilary A; Madhok, Rajan; Porter, Duncan R; Munro, Robin A L; McInnes, Iain B; Hunter, John A; Steven, Malcolm; Zoma, Asad; Morrison, Elaine; Sambrook, Martin; Poon, Fat Wui; Hampson, Rosemary; McDonald, Fiona; Tierney, Ann; Henderson, Neil; Ford, Ian

    2007-01-01

    Background Optimal use of disease‐modifying antirheumatic drugs (DMARDs) in rheumatoid arthritis is vital if progression of disease is to be reduced. Methotrexate (MTX) and sulfasalazine (SASP) are widely used inexpensive DMARDs, recently often combined despite no firm evidence of benefit from previous studies. Aim To establish whether a combination of SASP and MTX is superior to either drug alone in patients with rheumatoid arthritis with a suboptimal response to 6 months of SASP. Methods A randomised controlled study of step‐up DMARD treatment in early rheumatoid arthritis. In phase I, 687 patients received SASP for 6 months. Those with a disease activity score (DAS) ⩾2.4 were offered additional treatment in phase II (SASP alone, MTX alone or a combination of the two). The primary outcome measure was change in DAS. Results At 6 months, 191 (28%) patients had a DAS <2.4, 123 (18%) were eligible but did not wish to enter phase II, 130 (19%) stopped SASP because of reversible adverse events and 165 (24%) entered phase II. DAS at 18 months was significantly lower in those who received combination treatment compared with those who received either SASP or MTX: monotherapy arms did not differ. Improvement in European League Against Rheumatism and American College of Rheumatology 20, 50 and 70 scores favoured combination therapy. Conclusions In this “true‐to‐life” study, an inexpensive combination of DMARDs proved more effective than monotherapy in patients with rheumatoid arthritis with a suboptimal response to SASP. There was no increase in toxicity. These results provide an evidence base for the use of this combination as a component of tight control strategies. PMID:16926184

  12. Efficacy of switching from adefovir to tenofovir in chronic hepatitis B patients who exhibit suboptimal responses to adefovir-based combination rescue therapy due to resistance to nucleoside analogues (SATIS study

    Directory of Open Access Journals (Sweden)

    Hye Won Lee

    2016-12-01

    Full Text Available Background/Aims It remains to be determined whether switching from adefovir (ADV to tenofovir (TDF provides better virological outcomes in patients exhibiting suboptimal responses to ADV plus nucleoside analogue (ADV+NA therapy for NA-resistant chronic hepatitis B (CHB. Methods In this prospective trial, patients who showed partial responses (defined as serum hepatitis B virus [HBV] DNA >60 IU/mL to ADV+NA therapy for NA resistance were randomly allocated to receive TDF plus NA (TDF+NA group, n=16 or to continue their current therapy (ADV+NA group, n=16. The primary end point was the proportion of patients with complete virological response (CVR, defined as serum HBV DNA 2log10 IU/mL was more likely in the TDF+NA group at both 24 and 48 weeks (68.8% vs. 56.3%, P=0.014 vs. 81.3% vs. 56.3%, P=0.001, respectively. During the follow-up, the rate of HBeAg seroconversion was higher in the TDF+NA group than the ADV+NA group (12.5% vs. 6.25%, P=0.640, as was that for the hepatitis B surface antigen (6.25% vs. 0%, P=0.080. No serious adverse events due to antiviral agents occurred. Conclusion In patients exhibiting suboptimal responses to ADV+NA therapy for NA-resistant CHB, switching from ADV to TDF might provide better virological outcomes.

  13. The impact of the omission or inadequate dosing of radiotherapy in extranodal natural killer T-cell lymphoma, nasal type, in the United States.

    Science.gov (United States)

    Vargo, John A; Patel, Arisha; Glaser, Scott M; Balasubramani, Goundappa K; Farah, Rafic J; Marks, Stanley M; Beriwal, Sushil

    2017-08-15

    Extranodal natural killer T-cell lymphoma, nasal-type (NKTCL), is a rare malignancy in Western populations and is thus challenging for standardization of care and a prospective study. This study was aimed at defining patterns of care for NKTCL in the context of radiotherapy (RT) use and dose selection in the United States. Six hundred forty-two stage I-II NKTCL patients from 1998 to 2012 were identified from the National Cancer Data Base. Binary logistic regression analyses were performed to identify sociodemographic, treatment, and tumor characteristics predictive of the treatment selection and RT dose. Overall survival (OS) analyses were completed with the Kaplan-Meier and Cox multivariate methods, including a propensity score adjustment for a potential indication bias. Of the 642 included NKTCL patients, 70% were at stage I, 79% were white, and 66% were ≤ 60 years old. Fifty-five percent received chemotherapy plus RT, 19% received RT alone, and 27% received chemotherapy alone. The median RT dose was 50 Gy (interquartile range, 43.2-54 Gy), 37% received hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.23-0.70; P < .01), for chemotherapy plus RT at <50 Gy (HR, 0.55, 95% CI, 0.36-0.86; P < .01), and for chemotherapy plus RT at ≥50 Gy (HR, 0.41; 95% CI, 0.27-0.63; P < .01). Stage I-II NKTCL patients in the United States commonly receive chemotherapy alone or suboptimal-dose RT. The omission of RT or the use of suboptimal RT is negatively associated with OS. Efforts to continue improving evidenced-based management are warranted. Cancer 2017;123:3176-85. © 2017 American Cancer Society. © 2017 American Cancer Society.

  14. Design of a multicentre randomized controlled trial to assess the safety and efficacy of dose titration by specialized nurses in patients with heart failure. ETIFIC study protocol.

    Science.gov (United States)

    Oyanguren, Juana; García-Garrido, LLuisa; Nebot Margalef, Magdalena; Lekuona, Iñaki; Comin-Colet, Josep; Manito, Nicolás; Roure, Julia; Ruiz Rodriguez, Pilar; Enjuanes, Cristina; Latorre, Pedro; Torcal Laguna, Jesús; García-Gutiérrez, Susana

    2017-11-01

    Heart failure (HF) is associated with many hospital admissions and relatively high mortality, rates decreasing with administration of beta-blockers (BBs), angiotensin-converting-enzyme inhibitors, angiotensin II receptor blockers, and mineralocorticoid receptor antagonists. The effect is dose dependent, suboptimal doses being common in clinical practice. The 2012 European guidelines recommend close monitoring and dose titration by HF nurses. Our main aim is to compare BB doses achieved by patients after 4 months in intervention (HF nurse-managed) and control (cardiologist-managed) groups. Secondary aims include comparing doses of the other aforementioned drugs achieved after 4 months, adverse events, and outcomes at 6 months in the two groups. We have designed a multicentre (20 hospitals) non-inferiority randomized controlled trial, including patients with new-onset HF, left ventricular ejection fraction ≤40%, and New York Heart Association class II-III, with no contraindications to BBs. We will also conduct qualitative analysis to explore potential barriers to and facilitators of dose titration by HF nurses. In the intervention group, HF nurses will implement titration as prescribed by cardiologists, following a protocol. In controls, cardiologists will both prescribe and titrate doses. The study variables are doses of each of the drugs after 4 months relative to the target dose (%), New York Heart Association class, left ventricular ejection fraction, N-terminal pro B-type natriuretic peptide levels, 6 min walk distance, comorbidities, renal function, readmissions, mortality, quality of life, and psychosocial characteristics. The trial seeks to assess whether titration by HF nurses of drugs recommended in practice guidelines is safe and not inferior to direct management by cardiologists. The results could have an impact on clinical practice. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of

  15. Atmospheric radiation flight dose rates

    Science.gov (United States)

    Tobiska, W. K.

    2015-12-01

    Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the domains that are affected by space weather, the coupling between the solar and galactic high-energy particles, the magnetosphere, and atmospheric regions can significantly affect humans and our technology as a result of radiation exposure. Space Environment Technologies (SET) has been conducting space weather observations of the atmospheric radiation environment at aviation altitudes that will eventually be transitioned into air traffic management operations. The Automated Radiation Measurements for Aerospace Safety (ARMAS) system and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) both are providing dose rate measurements. Both activities are under the ARMAS goal of providing the "weather" of the radiation environment to improve aircraft crew and passenger safety. Over 5-dozen ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the real-time radiation environment resulting from Galactic Cosmic Rays and Solar Energetic Particles. The real-time radiation exposure is computed as an effective dose rate (body-averaged over the radiative-sensitive organs and tissues in units of microsieverts per hour); total ionizing dose is captured on the aircraft, downlinked in real-time, processed on the ground into effective dose rates, compared with NASA's Langley Research Center (LaRC) most recent Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) global radiation climatology model runs, and then made available to end users via the web and smart phone apps. Flight altitudes now exceed 60,000 ft. and extend above commercial aviation altitudes into the stratosphere. In this presentation we describe recent ARMAS and USEWX results.

  16. [Single dose treatment of trichomoniasis].

    Science.gov (United States)

    Erb, H

    1975-01-01

    The present regiman for the treatment of trichomoniasis with Tinidazol is 150 mg. twice daily for 7 days with a total dose of 2,100 mg. The success rate of this regimen is 85-90%. With a single dosage treatment of 2,000 mg. (Four 500 mg. tablets for the patient and her sexual partner) the success rate improved to 100%. Toxic side effects were not observed. The treatment was well tolerated and well accepted.

  17. Tolerance doses for treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Lyman, J.T.

    1985-10-01

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD/sub 5/) or 50% (TD/sub 50/) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs.

  18. Converting absorbed dose to medium to absorbed dose to water for Monte Carlo based photon beam dose calculations

    Science.gov (United States)

    Siebers, J. V.; Keall, P. J.; Nahum, A. E.; Mohan, R.

    2000-04-01

    Current clinical experience in radiation therapy is based upon dose computations that report the absorbed dose to water, even though the patient is not made of water but of many different types of tissue. While Monte Carlo dose calculation algorithms have the potential for higher dose accuracy, they usually transport particles in and compute the absorbed dose to the patient media such as soft tissue, lung or bone. Therefore, for dose calculation algorithm comparisons, or to report dose to water or tissue contained within a bone matrix for example, a method to convert dose to the medium to dose to water is required. This conversion has been developed here by applying Bragg-Gray cavity theory. The dose ratio for 6 and 18 MV photon beams was determined by computing the average stopping power ratio for the primary electron spectrum in the transport media. For soft tissue, the difference between dose to medium and dose to water is approximately 1.0%, while for cortical bone the dose difference exceeds 10%. The variation in the dose ratio as a function of depth and position in the field indicates that for photon beams a single correction factor can be used for each particular material throughout the field for a given photon beam energy. The only exception to this would be for the clinically non-relevant dose to air. Pre-computed energy spectra for 60 Co to 24 MV are used to compute the dose ratios for these photon beams and to determine an effective energy for evaluation of the dose ratio.

  19. Assessment of Filtered Back Projection, Adaptive Statistical, and Model-Based Iterative Reconstruction for Reduced Dose Abdominal Computed Tomography.

    Science.gov (United States)

    Padole, Atul; Singh, Sarabjeet; Lira, Diego; Blake, Michael A; Pourjabbar, Sarvenaz; Khawaja, Ranish Deedar Ali; Choy, Garry; Saini, Sanjay; Do, Synho; Kalra, Mannudeep K

    2015-01-01

    To compare standard of care and reduced dose (RD) abdominal computed tomography (CT) images reconstructed with filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), model-based iterative reconstruction (MBIR) techniques. In an Institutional Review Board-approved, prospective clinical study, 28 patients (mean age 59 ± 13 years ), undergoing clinically indicated routine abdominal CT on a 64-channel multi-detector CT scanner, gave written informed consent for acquisition of an additional RD (reconstructed with FBP, ASIR, and MBIR and compared with FBP images of standard dose abdomen CT. Two radiologists performed randomized, independent, and blinded comparison for lesion detection, lesion margin, visibility of normal structures, and diagnostic confidence. Mean CT dose index volume was 10 ± 3.4 mGy and 1.3 ± 0.3 mGy for standard and RD CT, respectively. There were 73 "true positive" lesions detected on standard of care CT. Nine lesions (iterative reconstruction techniques used for reconstruction of RD data sets. The visibility of lesion margin was suboptimal in (23/28) patients with RD FBP, (15/28) patients with RD ASIR, and (14/28) patients with RD MBIR compared to standard of care FBP images (P iterative reconstruction techniques. Clinically significant lesions (reconstruction techniques (FBP, ASIR, and MBIR).

  20. Fluconazole population pharmacokinetics and dosing for prevention and treatment of invasive Candidiasis in children supported with extracorporeal membrane oxygenation.

    Science.gov (United States)

    Watt, Kevin M; Gonzalez, Daniel; Benjamin, Daniel K; Brouwer, Kim L R; Wade, Kelly C; Capparelli, Edmund; Barrett, Jeffrey; Cohen-Wolkowiez, Michael

    2015-07-01

    Candida infections are a leading cause of infectious disease-related death in children supported by extracorporeal membrane oxygenation (ECMO). The ECMO circuit can alter drug pharmacokinetics (PK); thus, standard fluconazole dosing may result in suboptimal drug exposures. The objective of our study was to determine the PK of fluconazole in children on ECMO. Forty children with 367 PK samples were included in the analysis. The PK data were analyzed using nonlinear mixed-effect modeling (NONMEM). A one-compartment model best described the data. Weight was included in the base model for clearance (CL) and volume of distribution (V). The final model included the effect of serum creatinine (SCR) level on CL and the effect of ECMO on V as follows: CL (in liters per hour) = 0.019 × weight × (SCR/0.4)(-0.29) × exp(ηCL) and V (in liters) = 0.93 × weight × 1.4(ECMO) × exp(ηV). The fluconazole V was increased in children supported by ECMO. Consequently, children on ECMO require a higher fluconazole loading dose for prophylaxis (12 mg/kg of body weight) and treatment (35 mg/kg) paired with standard maintenance doses to achieve exposures similar to those of children not on ECMO. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. A phase I dose escalation trial of vaccine replicon particles (VRP) expressing prostate-specific membrane antigen (PSMA) in subjects with prostate cancer.

    Science.gov (United States)

    Slovin, Susan F; Kehoe, Marissa; Durso, Robert; Fernandez, Celina; Olson, William; Gao, Jian P; Israel, Robert; Scher, Howard I; Morris, Stephen

    2013-01-30

    PSMA-VRP is a propagation defective, viral replicon vector system encoding PSMA under phase I evaluation for patients with castration resistant metastatic prostate cancer (CRPC). The product is derived from an attenuated strain of the alphavirus, Venezuelan Equine Encephalitis (VEE) virus, and incorporates multiple redundant safety features. In this first in human trial, two cohorts of 3 patients with CRPC metastatic to bone were treated with up to five doses of either 0.9×10(7)IU or 0.36×10(8)IU of PSMA-VRP at weeks 1, 4, 7, 10 and 18, followed by an expansion cohort of 6 patients treated with 0.36×10(8)IU of PSMA-VRP at weeks 1, 4, 7, 10 and 18. No toxicities were observed. In the first dose cohort, no PSMA specific cellular immune responses were seen but weak PSMA-specific signals were observed by ELISA. The remaining 9 patients, which included the higher cohort and the extension cohort, had no PSMA specific cellular responses. PSMA-VRP was well-tolerated at both doses. While there did not appear to be clinical benefit nor robust immune signals at the two doses studied, neutralizing antibodies were produced by both cohorts suggesting that dosing was suboptimal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Pharmacokinetics of Colistin Following a Single Dose of Intravenous Colistimethate Sodium in Critically Ill Neonates.

    Science.gov (United States)

    Nakwan, Narongsak; Usaha, Siripa; Chokephaibulkit, Kulkanya; Villani, Paola; Regazzi, Mario; Imberti, Roberto

    2016-11-01

    In this study, we sought to evaluate the pharmacokinetics of colistin after intravenous administration of colistimethate sodium (CMS) in the critically ill neonates with Gram-negative bacterial infections. A single intravenous dose of CMS [approximately 150,000 IU/kg, equivalent to 5 mg/kg colistin base activity (CBA)] was administered to 7 critically ill neonates. Mean (±SD) maximum plasma colistin concentration and area under the time-concentration curve from 0 to infinity were 3.0 ± 0.7 µg/mL and 25.3 ± 10.4 µg·h/mL, respectively. Time to maximum concentration, half-life, apparent volume of distribution and clearance were 1.3 ± 0.9 hours, 9.0 ± 6.5 hours, 7.7 ± 9.3 L/kg and 0.6 ± 0.3 L/h/kg, respectively. After a dose regimen of 5 mg/kg CBA every 24 hours, the average concentration expected at steady state is 1.1 ± 0.4 µg/mL. In critically ill neonates, a single intravenous dose of 5 mg CBA/kg (approximately 150,000 IU/kg of CMS) resulted in suboptimal plasma concentrations of colistin. According to our pharmacokinetics data, the dosage of CMS currently used in critically ill neonates is insufficient.

  3. Loratadine: multiple-dose pharmacokinetics.

    Science.gov (United States)

    Radwanski, E; Hilbert, J; Symchowicz, S; Zampaglione, N

    1987-07-01

    The steady-state pharmacokinetics of loratadine (L), a new long-acting antihistamine devoid of CNS activity, was investigated in 12 healthy male volunteers. Each volunteer received 40-mg L capsules q24h for ten days. Blood samples were collected at various times on day 1, 5, 7, and 10 and assayed for L by radioimmunoassay (RIA) and for descarboethoxyloratadine (DCL), a known active metabolite, by high-performance liquid chromatography (HPLC). The plasma L and DCL concentration-time data in the disposition phases were fitted to a biexponential equation for pharmacokinetic analysis. Steady-state plasma L Cmax concentrations were reached at 1.5 hour (Tmax) after each dose. DCL steady-state Cmax values ranged 26 to 29 ng/mL at a Tmax ranging from 1.8 to 3 hours. The AUC at steady state, AUC tau, was 80 to 96 and 349 to 421 h X ng/mL for L and DCL, respectively. The accumulation indexes (Ra) based on AUC tau ratios, did not change for either compound after day 5. Ra values for L and DCL after the fifth dose were 1.4 and 1.9, respectively, indicating that there is little accumulation of either L or DCL after a multiple (once-a-day) dosage regimen. The t1/2 beta at steady state were 14.4 and 18.7 hours for L and DCL, respectively, which were similar to those reported following a single-dose L administration. Observed plasma drug concentrations were in good agreement with predicted values derived for pharmacokinetic parameters.

  4. Low-dose radiation exposure and carcinogenesis

    National Research Council Canada - National Science Library

    Suzuki, Keiji; Yamashita, Shunichi

    2012-01-01

    .... Epidemiological studies have demonstrated the dose-response relationships for cancer induction and quantitative evaluations of cancer risk following exposure to moderate to high doses of low-linear...

  5. Dose-mapping distribution around MNSR

    CERN Document Server

    Jamal, M H

    2002-01-01

    The aim of this study is to establish the dose-rate map through the determination of radiological dose-rate levels in reactor hall, adjacent rooms, and outside the MNSR facility. Controlling dose rate to reactor operating personnel , dose map was established. The map covers time and distances in the reactor hall, during reactor operation at nominal power. Different measurement of dose rates in other areas of the reactor buildings was established. The maximum dose rate, during normal operation of the MNSR was 40 and 21 Sv/hr on the top of the reactor and near the pool fence, respectively. Whereas, gamma and neutron doses have not exceeded natural background in all rooms adjacent to the reactor hall or nearly buildings. The relation between the dose rate for gamma rays and neutron flux at the top of cover of reactor pool was studied as well. It was found that this relation is linear.

  6. Dose to water versus dose to medium in proton beam therapy

    Science.gov (United States)

    Paganetti, Harald

    2009-07-01

    Dose in radiation therapy is traditionally reported as the water-equivalent dose, or dose to water. Monte Carlo dose calculations report dose to medium and thus a methodology is needed to convert dose to medium into dose to water (or vice versa) for comparison of Monte Carlo results with results from planning systems. This paper describes the development of a formalism to convert dose to medium into dose to water for proton fields when simulating the dose with Monte Carlo techniques. The conversion is based on relative stopping power but also considers energy transferred via nuclear interactions. The influence of different interaction mechanisms of proton beams (electromagnetic versus nuclear) is demonstrated. Further, an approximate method for converting doses retroactively is presented. Based on the outlined formalism, five proton therapy patients with a total of 33 fields were analyzed. Dose distributions, dose volume histograms and absolute doses to assess the clinical significance of differences between dose to medium and dose to water are presented. We found that the difference between the two dose reporting definitions can be up to 10% for high CT numbers if analyzing the mean dose to the target. The difference is clinically insignificant for soft tissues. For the structures analyzed, the mean dose to water could be converted to dose to medium by applying a correction factor increasing linearly with increasing average CT number in the volume. We determined that an approximate conversion method, done retroactively with an energy-independent stopping power ratio and without considering nuclear interaction events separately (as compared to on-the-fly conversion during simulation), is sufficiently accurate to compute mean doses. It is insufficient, however, when analyzing the beam range. For proton beams stopping in bony anatomy, the predicted beam range can differ by 2-3 mm when comparing dose to tissue and dose to water.

  7. Genetic warfarin dosing: tables versus algorithms.

    Science.gov (United States)

    Finkelman, Brian S; Gage, Brian F; Johnson, Julie A; Brensinger, Colleen M; Kimmel, Stephen E

    2011-02-01

    The aim of this study was to compare the accuracy of genetic tables and formal pharmacogenetic algorithms for warfarin dosing. Pharmacogenetic algorithms based on regression equations can predict warfarin dose, but they require detailed mathematical calculations. A simpler alternative, recently added to the warfarin label by the U.S. Food and Drug Administration, is to use genotype-stratified tables to estimate warfarin dose. This table may potentially increase the use of pharmacogenetic warfarin dosing in clinical practice; however, its accuracy has not been quantified. A retrospective cohort study of 1,378 patients from 3 anticoagulation centers was conducted. Inclusion criteria were stable therapeutic warfarin dose and complete genetic and clinical data. Five dose prediction methods were compared: 2 methods using only clinical information (empiric 5 mg/day dosing and a formal clinical algorithm), 2 genetic tables (the new warfarin label table and a table based on mean dose stratified by genotype), and 1 formal pharmacogenetic algorithm, using both clinical and genetic information. For each method, the proportion of patients whose predicted doses were within 20% of their actual therapeutic doses was determined. Dosing methods were compared using McNemar's chi-square test. Warfarin dose prediction was significantly more accurate (all p algorithm (52%) than with all other methods: empiric dosing (37%; odds ratio [OR]: 2.2), clinical algorithm (39%; OR: 2.2), warfarin label (43%; OR: 1.8), and genotype mean dose table (44%; OR: 1.9). Although genetic tables predicted warfarin dose better than empiric dosing, formal pharmacogenetic algorithms were the most accurate. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. Hanford Environmental Dose Reconstruction Project. Monthly report

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, S.D.; Finch, S.M. [comps.

    1992-10-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

  9. CT radiation dose and iterative reconstruction techniques.

    Science.gov (United States)

    Padole, Atul; Ali Khawaja, Ranish Deedar; Kalra, Mannudeep K; Singh, Sarabjeet

    2015-04-01

    1. CT radiation dose optimization is one of the major concerns for the scientific community. 2. CT image quality is dependent on the selected image reconstruction algorithm. 3. Iterative reconstruction algorithms have reemerged with the potential of radiation dose optimization by lowering image noise. 4. Tube current is the most common parameter used to reduce radiation dose along with iterative reconstruction. 5. Tube potential (kV) is also used for dose optimization with iterative reconstruction in CT angiography protocols and small patients.

  10. Adaption By Low Dose Radiation Exposure

    OpenAIRE

    Mitchel, Ron E.J.

    2015-01-01

    The procedures and dose limitations used for radiation protection in the nuclear industry are founded on the assumption that risk is directly proportional to dose, without a threshold. Based on this idea that any dose, no matter how small, will increase risk, radiation protection regulations generally attempt to reduce any exposure to ?as low as reasonably achievable? (ALARA). We know however, that these regulatory assumptions are inconsistent with the known biological effects of low doses. L...

  11. Low-Dose Pretreatment for Radiation Therapy

    OpenAIRE

    Blankenbecler, Richard

    2010-01-01

    In radiotherapy, a large radiation dose must be applied to both cancer and neighboring healthy cells. Recent experiments have shown that a low dose of ionizing radiation turns on certain protective mechanisms that allow a cell to better survive a subsequent high dose of radiation. This adaptive response can have important and positive consequences for radiotherapy. This paper describes a simple change in treatment procedures to make use of these beneficial effects. A low dose applied only to ...

  12. A dose monitoring system for dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chena; Lee, Sam Sun; Kim, Jo Eun; Huh, Kyung Hoe; Yi, Woo Jin; Heo, Min Suk; Choi, Soon Chul [Dept. of Oral and Maxillofacial Radiology and Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Symkhampha, Khanthaly [Dept. of Oral and Maxillofacial Radiology, Department of Basic Science, Faculty of Dentistry, University of Health Sciences, Vientiane (Lao People' s Democratic Republic); Lee, Woo Jin [Dept. of Interdisciplinary Program in Radiation, Applied Life Sciences Major, College of Medicine, BK21, and Dental Research Institute, Seoul National University, Seoul (Korea, Republic of); Yeom, Heon Young [School of Computer Science Engineering, Seoul National University, Seoul (Korea, Republic of)

    2016-06-15

    The current study investigates the feasibility of a platform for a nationwide dose monitoring system for dental radiography. The essential elements for an unerring system are also assessed. An intraoral radiographic machine with 14 X-ray generators and five sensors, 45 panoramic radiographic machines, and 23 cone-beam computed tomography (CBCT) models used in Korean dental clinics were surveyed to investigate the type of dose report. A main server for storing the dose data from each radiographic machine was prepared. The dose report transfer pathways from the radiographic machine to the main sever were constructed. An effective dose calculation method was created based on the machine specifications and the exposure parameters of three intraoral radiographic machines, five panoramic radiographic machines, and four CBCTs. A viewing system was developed for both dentists and patients to view the calculated effective dose. Each procedure and the main server were integrated into one system. The dose data from each type of radiographic machine was successfully transferred to the main server and converted into an effective dose. The effective dose stored in the main server is automatically connected to a viewing program for dentist and patient access. A patient radiation dose monitoring system is feasible for dental clinics. Future research in cooperation with clinicians, industry, and radiologists is needed to ensure format convertibility for an efficient dose monitoring system to monitor unexpected radiation dose.

  13. Failure-probability driven dose painting

    DEFF Research Database (Denmark)

    Vogelius, Ivan R; Håkansson, Katrin; Due, Anne K

    2013-01-01

    To demonstrate a data-driven dose-painting strategy based on the spatial distribution of recurrences in previously treated patients. The result is a quantitative way to define a dose prescription function, optimizing the predicted local control at constant treatment intensity. A dose planning study...

  14. Chemical Dosing and First-Order Kinetics

    Science.gov (United States)

    Hladky, Paul W.

    2011-01-01

    College students encounter a variety of first-order phenomena in their mathematics and science courses. Introductory chemistry textbooks that discuss first-order processes, usually in conjunction with chemical kinetics or radioactive decay, stop at single, discrete dose events. Although single-dose situations are important, multiple-dose events,…

  15. Efficient implementation of the 3D-DDA ray traversal algorithm on GPU and its application in radiation dose calculation.

    Science.gov (United States)

    Xiao, Kai; Chen, Danny Z; Hu, X Sharon; Zhou, Bo

    2012-12-01

    The three-dimensional digital differential analyzer (3D-DDA) algorithm is a widely used ray traversal method, which is also at the core of many convolution∕superposition (C∕S) dose calculation approaches. However, porting existing C∕S dose calculation methods onto graphics processing unit (GPU) has brought challenges to retaining the efficiency of this algorithm. In particular, straightforward implementation of the original 3D-DDA algorithm inflicts a lot of branch divergence which conflicts with the GPU programming model and leads to suboptimal performance. In this paper, an efficient GPU implementation of the 3D-DDA algorithm is proposed, which effectively reduces such branch divergence and improves performance of the C∕S dose calculation programs running on GPU. The main idea of the proposed method is to convert a number of conditional statements in the original 3D-DDA algorithm into a set of simple operations (e.g., arithmetic, comparison, and logic) which are better supported by the GPU architecture. To verify and demonstrate the performance improvement, this ray traversal method was integrated into a GPU-based collapsed cone convolution∕superposition (CCCS) dose calculation program. The proposed method has been tested using a water phantom and various clinical cases on an NVIDIA GTX570 GPU. The CCCS dose calculation program based on the efficient 3D-DDA ray traversal implementation runs 1.42 ∼ 2.67× faster than the one based on the original 3D-DDA implementation, without losing any accuracy. The results show that the proposed method can effectively reduce branch divergence in the original 3D-DDA ray traversal algorithm and improve the performance of the CCCS program running on GPU. Considering the wide utilization of the 3D-DDA algorithm, various applications can benefit from this implementation method.

  16. A novel model-based approach for dose determination of glycopyrronium bromide in COPD

    Directory of Open Access Journals (Sweden)

    Arievich Helen

    2012-12-01

    Full Text Available Abstract Background Glycopyrronium bromide (NVA237 is an inhaled long-acting muscarinic antagonist in development for treatment of COPD. This study compared the efficacy and safety of once-daily (OD and twice-daily (BID glycopyrronium bromide regimens, using a novel model-based approach, in patients with moderate-to-severe COPD. Methods Double-blind, randomized, dose-finding trial with an eight-treatment, two-period, balanced incomplete block design. Patients (smoking history ≥10 pack-years, post-bronchodilator FEV1 ≥30% and 1/FVC 1 at Day 28. Results 385 patients (mean age 61.2 years; mean post-bronchodilator FEV1 53% predicted were randomized; 88.6% completed. All OD and BID dosing regimens produced dose-dependent bronchodilation; at Day 28, increases in mean trough FEV1 versus placebo were statistically significant for all regimens, ranging from 51 mL (glycopyrronium bromide 12.5 μg OD to 160 mL (glycopyrronium bromide 50 μg BID. Pharmacodynamic steady-state was reached by Day 7. There was a small separation (≤37 mL between BID and OD dose–response curves for mean trough FEV1 at steady-state in favour of BID dosing. Over 24 hours, separation between OD and BID regimens was even smaller (FEV1 AUC0-24h maximum difference for equivalent daily dose regimens: 8 mL. Dose–response results for FEV1 at 12 hours, FEV1 AUC0-12h and FEV1 AUC0-4h at steady-state showed OD regimens provided greater improvement over placebo than BID regimens for total daily doses of 25 μg, 50 μg and 100 μg, while the reverse was true for OD versus BID regimens from 12–24 hours. The 12.5 μg BID dose produced a marginally higher improvement in trough FEV1 versus placebo than 50 μg OD, however, the response at 12 hours over placebo was suboptimal (74 mL. Glycopyrronium bromide was safe and well tolerated at all doses. Conclusions Glycopyrronium bromide 50 μg OD provides significant bronchodilation over a 24 hour period

  17. Metrics, Dose, and Dose Concept: The Need for a Proper Dose Concept in the Risk Assessment of Nanoparticles

    Directory of Open Access Journals (Sweden)

    Myrtill Simkó

    2014-04-01

    Full Text Available In order to calculate the dose for nanoparticles (NP, (i relevant information about the dose metrics and (ii a proper dose concept are crucial. Since the appropriate metrics for NP toxicity are yet to be elaborated, a general dose calculation model for nanomaterials is not available. Here we propose how to develop a dose assessment model for NP in analogy to the radiation protection dose calculation, introducing the so-called “deposited and the equivalent dose”. As a dose metric we propose the total deposited NP surface area (SA, which has been shown frequently to determine toxicological responses e.g. of lung tissue. The deposited NP dose is proportional to the total surface area of deposited NP per tissue mass, and takes into account primary and agglomerated NP. By using several weighting factors the equivalent dose additionally takes into account various physico-chemical properties of the NP which are influencing the biological responses. These weighting factors consider the specific surface area, the surface textures, the zeta-potential as a measure for surface charge, the particle morphology such as the shape and the length-to-diameter ratio (aspect ratio, the band gap energy levels of metal and metal oxide NP, and the particle dissolution rate. Furthermore, we discuss how these weighting factors influence the equivalent dose of the deposited NP.

  18. Optimizing lithium dosing in hemodialysis

    DEFF Research Database (Denmark)

    Bjarnason, N H; Munkner, R; Kampmann, J P

    2006-01-01

    We studied a 62-year-old female hemodialysis patient during initiation and maintenance of lithium carbonate therapy. Three different methods were applied to estimate the regimen: a scenario based on volume of distribution (V(d)), a scenario based on glomerular filtration rate (GFR), and a scenario...... estimates. Furthermore, the maintenance dose estimated from the central compartment (V1) led to plasma concentrations within the therapeutic range. Thus, a regimen where 12.2 mmol lithium was given after each hemodialysis session resulted in stable between-dialysis plasma lithium concentrations...... in this patient with no residual kidney function. We did not observe adverse effects related to this regimen, which was monitored from 18 days to 8 months of therapy, and the patient experienced relief from her severe depressive disorder. In conclusion, dialysis patients may be treated with lithium administrated...

  19. The Dose Makes The Cooperation

    CERN Document Server

    Cetin, Uzay

    2016-01-01

    Explaining cooperation is one of the greatest challenges for basic scientific research. We proposed an agent-based model to study co-evolution of memory and cooperation. In our model, reciprocal agents with limited memory size play Prisoner's Dilemma Game iteratively. The characteristic of the environment, whether it is threatening or not, is embedded in the payoff matrix. Our findings are as follows. (i) Memory plays a critical role in the protection of cooperation. (ii) In the absence of threat, subsequent generations loose their memory and are consequently invaded by defectors. (iii) In contrast, the presence of an appropriate level of threat triggers the emergence of a self-protection mechanism for cooperation within subsequent generations. On the evolutionary level, memory size acts like an immune response of the population against aggressive defection. (iv) Even more extreme threat results again in defection. Our findings boil down to the following: The dose of the threat makes the cooperation.

  20. Sub-Optimal Treatment of Bacterial Biofilms

    Directory of Open Access Journals (Sweden)

    Tianyan Song

    2016-06-01

    Full Text Available Bacterial biofilm is an emerging clinical problem recognized in the treatment of infectious diseases within the last two decades. The appearance of microbial biofilm in clinical settings is steadily increasing due to several reasons including the increased use of quality of life-improving artificial devices. In contrast to infections caused by planktonic bacteria that respond relatively well to standard antibiotic therapy, biofilm-forming bacteria tend to cause chronic infections whereby infections persist despite seemingly adequate antibiotic therapy. This review briefly describes the responses of biofilm matrix components and biofilm-associated bacteria towards sub-lethal concentrations of antimicrobial agents, which may include the generation of genetic and phenotypic variabilities. Clinical implications of bacterial biofilms in relation to antibiotic treatments are also discussed.

  1. How suboptimal are linear sharing rules?

    DEFF Research Database (Denmark)

    Jensen, Bjarne Astrup; Nielsen, Jørgen Aase

    2016-01-01

    The objective of this paper is to analyze criteria for portfolio choice when two investors are forced to invest in a common portfolio and share the proceeds by a linear sharing rule. A similar situation with many investors is typical for defined contribution pension schemes. The restriction impli...

  2. Reasons for Suboptimal Learning in Medical Microbiology

    Science.gov (United States)

    Struwig, Magdalena C.; Beylefeld, Adriana A.; Joubert, Georgina

    2016-01-01

    Medical microbiology presents a challenge to undergraduate students, mostly due to its extensive content and complexity of unfamiliar terminology. In addition to a narrative review of the literature, we report findings on students' motivation for and approach to learning in the Infections module of an undergraduate medical curriculum, and their…

  3. Dependent Interviewing and Sub-Optimal Responding

    Directory of Open Access Journals (Sweden)

    Johannes Eggs

    2015-02-01

    Full Text Available With proactive dependent interviewing (PDI respondents are reminded of the answer they gave in the previous interview, before being asked about their current status. PDI is used in panel surveys to assist respondent recall and reduce spurious changes in responses over time. PDI may however provide scope for new errors if respondents falsely accept the previous information as still being an accurate description of their current situation. In this paper we use data from the German Labour Market and Social Security panel study, in which an error was made with the preload data for a PDI question about receipt of welfare benefit. The survey data were linked to individual administrative records on receipt of welfare benefit. A large proportion of respondents accepted the false preload. This behaviour seems mainly driven by the difficulty of the response task: respondents with a more complex history of receipt according to the records were more likely to confirm the false preload. Personality also seemed related to the probability of confirming. Predictors of satisficing, indicators of satisficing on other items in the survey, and characteristics of the survey and interviewer were not predictive of confirming the false preload.

  4. Effects of Suboptimal Bidding in Combinatorial Auctions

    Science.gov (United States)

    Schneider, Stefan; Shabalin, Pasha; Bichler, Martin

    Though the VCG auction assumes a central place in the mechanism design literature, there are a number of reasons for favoring iterative combinatorial auction designs. Several promising ascending auction formats have been developed throughout the past few years based on primal-dual and subgradient algorithms and linear programming theory. Prices are interpreted as a feasible dual solution and the provisional allocation is interpreted as a feasible primal solution. iBundle( 3) (Parkes and Ungar 2000), dVSV (de Vries et al. 2007) and the Ascending Proxy auction (Ausubel and Milgrom 2002) result in VCG payoffs when the coalitional value function satisfies the buyer submodularity condition and bidders bid straightforward, which is an expost Nash equilibrium in that case. iBEA and CreditDebit auctions (Mishra and Parkes 2007) do not even require the buyer submodularity condition and achieve the same properties for general valuations. In many situations, however, one cannot assume bidders to bid straightforward and it is not clear from the theory how these non-linear personalized price auctions (NLPPAs) perform in this case. Robustness of auctions with respect to different bidding behavior is therefore a critical issue for any application. We have conducted a large number of computational experiments to analyze the performance of NLPPA designs with respect to different bidding strategies and different valuation models. We compare the results of NLPPAs to those of the VCG auction and those of iterative combinatorial auctions with approximate linear prices, such as ALPS (Bichler et al. 2009) and the Combinatorial Clock auction (Porter et al. 2003).

  5. ADAPTIVE SUBOPTIMAL CONTROL OF INPUT CONSTRAINED PLANTS

    Directory of Open Access Journals (Sweden)

    Valerii Azarskov

    2011-03-01

    Full Text Available Abstract. This paper deals with adaptive regulation of a discrete-time linear time-invariant plant witharbitrary bounded disturbances whose control input is constrained to lie within certain limits. The adaptivecontrol algorithm exploits the one-step-ahead control strategy and the gradient projection type estimationprocedure using the modified dead zone. The convergence property of the estimation algorithm is shown tobe ensured. The sufficient conditions guaranteeing the global asymptotical stability and simultaneously thesuboptimality of the closed-loop systems are derived. Numerical examples and simulations are presented tosupport the theoretical results.

  6. Suboptimal Micronutrient Intake among Children in Europe

    Directory of Open Access Journals (Sweden)

    Boris Kaganov

    2015-05-01

    Full Text Available Adequate dietary intake of micronutrients is not necessarily achieved even in resource-rich areas of the world wherein overeating is a public health concern. In Europe, population-based data suggests substantial variability in micronutrient intake among children. Two independent surveys of micronutrient consumption among European children were evaluated. Stratified by age, the data regarding micronutrient intake were evaluated in the context of daily requirements, which are typically estimated in the absence of reliable absolute values derived from prospective studies. The proportion of children living in Europe whose intake of at least some vitamins and trace elements are at or below the estimated average requirements is substantial. The most common deficiencies across age groups included vitamin D, vitamin E, and iodine. Specific deficiencies were not uniform across countries or by age or gender.  Micronutrient intake appears to be more strongly influenced by factors other than access to food. Substantial portions of European children may be at risk of reversible health risks from inadequate intake of micronutrients. Despite the growing health threat posed by excess intake of calories, adequate exposure to vitamins, trace elements, and other micronutrients may deserve attention in public health initiatives to optimize growth and development in the European pediatric population.

  7. On the Suboptimality of Linear Lossy Codes

    Science.gov (United States)

    Kuzuoka, Shigeaki

    This letter reveals that linear lossy codes cannot attain the rate-distortion function in general, even if the source is binary i. i. d. and the distortion is measured by the Hamming distortion measure.

  8. Ambient dose equivalents in TGFs

    Science.gov (United States)

    Celestin, Sebastien; Pincon, Jean-Louis; Trompier, Francois

    2017-04-01

    Terrestrial gamma-ray flashes (TGFs) are bursts of high-energy photons originating from the Earth's atmosphere in association with thunderstorm activity [e.g., Briggs et al., JGR, 118, 3805, 2013]. TGFs are associated with initial propagation stages of intracloud lightning, which represent the most frequent type of lightning discharges [e.g., Cummer et al., GRL, 42, 7792, 2015, and references therein]. TGFs are known to be produced inside common thunderclouds [e.g., Splitt et al., JGR, 115, A00E38, 2010] typically at altitudes ranging from 10 to 14 km [e.g., Cummer et al., GRL, 41, 8586, 2014]. The global TGF occurrence rate is estimated to be 400,000 per year concerning TGFs detectable by Fermi-GBM (Gamma ray Burst Monitor) [Briggs et al., 2013], but detailed analysis of satellite measurements [Østgaard et al., JGR, 117, A03327, 2012] and theoretical studies [Celestin et al., JGR, 120, 10712, 2015] suggest that it cannot be excluded that TGFs represent a part of a regular process taking place during the propagation of lightning discharges. It is important to assess the risk induced by TGFs for airline passengers and crews on board aircraft approaching thunderstorms. Dwyer et al. [JGR, 115, D09206, 2010] have estimated that if an aircraft were to find itself in the source electron beam giving rise to a TGF, passengers and crews might receive effective radiation doses above the regulatory limit depending on the beam diameter. Moreover, Tavani et al. [Nat. Hazards Earth Syst. Sci., 13, 1127, 2013] concluded that TGF-associated neutrons produced by photonuclear reactions would cause serious hazard on the aircraft avionics. In this work, we will present detailed simulation-based estimations of effective doses received by humans that would be irradiated by TGFs for various production altitudes and distances from the TGF source.

  9. Exposure- and Dose-response Analyses in Dose Selection and Labeling of FDA-approved Biologics.

    Science.gov (United States)

    Ogasawara, Ken; Breder, Christopher D; Lin, Dora H; Alexander, G Caleb

    2018-01-01

    Biological drug products, or products derived from living cells, represent an increasingly important part of the pharmaceutical market. Despite this, little is known about how sponsors determine the dose to be studied in registrational trials or to be proposed in labeling for biologics. We examined how exposure-response and dose-response analyses were used to determine dosing in pivotal trials or the labeling for all biologics approved by the Center for Drug Evaluation and Research, the US Food and Drug Administration (FDA) between 2003 and 2016. We extracted relevant characteristics of each biologic from its review package by FDA. We used descriptive statistics to characterize the rationale for the selected dose(s) in registration trials, with a particular focus on the role of exposure-response/dose-response analyses. We also examined how exposure-response/dose-response analyses were used to support the labeling dose and the basis for postmarketing requirements or commitments related to dose optimization. A total of 79 biologics license applications were examined. Dose selection in registrational trials was more often attributed to clinical efficacy (73% of applications) than to clinical safety (42%). The dosing of products whose dose was apparently selected based on clinical efficacy was often (72%) determined by the dose-response relationship. In support of doses that were described in labeling, exposure-response analyses for efficacy were performed more commonly (53%) than dose-response analyses (21%). This trend was apparent after 2012. This is the first study to summarize the justification of dose selection and the labeled dose of biologics approved by the FDA. Dose-response analyses have been often used as the rationale for dose selection of registrational studies, although exposure-response analyses are becoming more prevalent in support of the dosing guidelines in labeling. Copyright © 2018 Elsevier HS Journals, Inc. All rights reserved.

  10. Prediction of midline dose from entrance ad exit dose using OSLD measurements for total irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Heon; Park, Jong Min; Park, So Yeon; Chun, Min Soo; Han, Ji Hye; Cho, Jin Dong; Kim, Jung In [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2017-06-15

    This study aims to predict the midline dose based on the entrance and exit doses from optically stimulated luminescence detector (OSLD) measurements for total body irradiation (TBI). For TBI treatment, beam data sets were measured for 6 MV and 15 MV beams. To evaluate the tissue lateral effect of various thicknesses, the midline dose and peak dose were measured using a solid water phantom (SWP) and ion chamber. The entrance and exit doses were measured using OSLDs. OSLDs were attached onto the central beam axis at the entrance and exit surfaces of the phantom. The predicted midline dose was evaluated as the sum of the entrance and exit doses by OSLD measurement. The ratio of the entrance dose to the exit dose was evaluated at various thicknesses. The ratio of the peak dose to the midline dose was 1.12 for a 30 cm thick SWP at both energies. When the patient thickness is greater than 30 cm, the 15 MV should be used to ensure dose homogeneity. The ratio of the entrance dose to the exit dose was less than 1.0 for thicknesses of less than 30 cm and 40 cm at 6 MV and 15 MV, respectively. Therefore, the predicted midline dose can be underestimated for thinner body. At 15 MV, the ratios were approximately 1.06 for a thickness of 50 cm. In cases where adult patients are treated with the 15 MV photon beam, it is possible for the predicted midline dose to be overestimated for parts of the body with a thickness of 50 cm or greater. The predicted midline dose and OSLD-measured midline dose depend on the phantom thickness. For in-vivo dosimetry of TBI, the measurement dose should be corrected in order to accurately predict the midline dose.

  11. [Phenylephrine dosing error in Intensive Care Unit. Case of the trimester].

    Science.gov (United States)

    2013-01-01

    A real clinical case reported to SENSAR is presented. A patient admitted to the surgical intensive care unit following a lung resection, suffered arterial hypotension. The nurse was asked to give the patient 1 mL of phenylephrine. A few seconds afterwards, the patient experienced a hypertensive crisis, which resolved spontaneously without damage. Thereafter, the nurse was interviewed and a dosing error was identified: she had mistakenly given the patient 1 mg of phenylephrine (1 mL) instead of 100 mcg (1 mL of the standard dilution, 1mg in 10 mL). The incident analysis revealed latent factors (event triggers) due to the lack of protocols and standard operating procedures, communication errors among team members (physician-nurse), suboptimal training, and underdeveloped safety culture. In order to preempt similar incidents in the future, the following actions were implemented in the surgical intensive care unit: a protocol for bolus and short lived infusions (<30 min) was developed and to close the communication gap through the adoption of communication techniques. The protocol was designed by physicians and nurses to standardize the administration of drugs with high potential for errors. To close the communication gap, repeated checks about saying and understanding was proposed ("closed loop"). Labeling syringes with the drug dilution was also recommended. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  12. Commissioning of applicator-guided stereotactic body radiation therapy boost with high-dose-rate brachytherapy for advanced cervical cancer using radiochromic film dosimetry.

    Science.gov (United States)

    Aldelaijan, Saad; Wadi-Ramahi, Shada; Nobah, Ahmad; Moftah, Belal; Devic, Slobodan; Jastaniyah, Noha

    To describe an EBT3 GAFCHROMIC film-based dosimetry method to be used in commissioning of a combined HDR brachytherapy (HDRB) and stereotactic body radiation therapy (SBRT) boost for treatment of advanced cervical cancer involving extensive residual disease after external beam treatment. A cube phantom was designed to firmly fit an intrauterine tandem applicator and EBT3 radiochromic film pieces. A high-risk clinical target volume (CTVHR, Total) was contoured with an extended arm at one side. The HDRB treatment was planned to cover the proximal CTVHR, Total with 7 Gy and the distal volume, referred to as CTVHR, Distal, was planned by SBRT for dose augmentation. After HDRB treatment delivery, SBRT treatment was delivered within 1 hour by image guidance using the applicator geometry. Intentional 1D and 2D misalignments were introduced to evaluate the effect on target volumes. In addition, effect of film reirradiation at different time gaps and dose levels was evaluated. Film dosimetric accuracy, with up to 2 hours gap between irradiations, was shown to be unaffected. A 2%/2 mm gamma analysis between measured and planned doses showed agreement of >99%. Misalignments of more than 2 mm between applicator and SBRT isocenter resulted in suboptimal dose-volume histogram affecting mostly D98% and D90% of CTVHR, Distal. Visualizing how target dose-volume metrics are affected by minor misalignments between SBRT and HDRB dose gradients, in light of achievable phantom-based experimental quality assurance level, encourages the clinical applicability of this technique. Radiochromic film was shown to be a valuable tool to commission procedures combining two different treatment planning systems and modalities with varying dose rates and energy ranges. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  13. Dose optimisation in single plane interstitial brachytherapy.

    Science.gov (United States)

    Tanderup, Kari; Hellebust, Taran Paulsen; Honoré, Henriette Benedicte; Nielsen, Søren Kynde; Olsen, Dag Rune; Grau, Cai; Lindegaard, Jacob Christian

    2006-10-01

    Brachytherapy dose distributions can be optimised by modulation of source dwell times. In this study dose optimisation in single planar interstitial implants was evaluated in order to quantify the potential benefit in patients. In 14 patients, treated for recurrent rectal and cervical cancer, flexible catheters were sutured intra-operatively to the tumour bed in areas with compromised surgical margin. Both non-optimised, geometrically and graphically optimised CT -based dose plans were made. The overdose index (OI), homogeneity index (HI), conformal index (COIN), minimum target dose, and high dose volumes were evaluated. The dependence of OI, HI, and COIN on target volume and implant regularity was evaluated. In addition, 12 theoretical implant configurations were analyzed. Geometrical and graphical optimisation improved the dose plans significantly with graphical optimisation being superior. Graphically optimised dose plans showed a significant decrease of 18%+/-9% in high dose volume (p<0.001). HI, COIN, and OI were significantly improved from 0.50+/-0.05 to 0.60+/-0.05, from 0.65+/-0.04 to 0.71+/-0.04, and from 0.19+/-0.03 to 0.15+/-0.03, respectively (p<0.001 for all). Moreover, minimum target dose increased significantly from 71%+/-5% to 80%+/-5% (p<0.001). The improvement in OI and HI obtained by optimisation depended on the regularity of the implant, such that the benefit of optimisation was larger for irregular implants. OI and HI correlated strongly with target volume limiting the usability of these parameters for comparison of dose plans between patients. Dwell time optimisation significantly improved the dose distribution regarding homogeneity, conformity, minimum target dose, and size of high dose volumes. Graphical optimisation is fast, reproducible and superior to geometric optimisation.

  14. Failure-probability driven dose painting

    Energy Technology Data Exchange (ETDEWEB)

    Vogelius, Ivan R.; Håkansson, Katrin; Due, Anne K.; Aznar, Marianne C.; Kristensen, Claus A.; Rasmussen, Jacob; Specht, Lena [Department of Radiation Oncology, Rigshospitalet, University of Copenhagen, Copenhagen 2100 (Denmark); Berthelsen, Anne K. [Department of Radiation Oncology, Rigshospitalet, University of Copenhagen, Copenhagen 2100, Denmark and Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Copenhagen 2100 (Denmark); Bentzen, Søren M. [Department of Radiation Oncology, Rigshospitalet, University of Copenhagen, Copenhagen 2100, Denmark and Departments of Human Oncology and Medical Physics, University of Wisconsin, Madison, Wisconsin 53792 (United States)

    2013-08-15

    Purpose: To demonstrate a data-driven dose-painting strategy based on the spatial distribution of recurrences in previously treated patients. The result is a quantitative way to define a dose prescription function, optimizing the predicted local control at constant treatment intensity. A dose planning study using the optimized dose prescription in 20 patients is performed.Methods: Patients treated at our center have five tumor subvolumes from the center of the tumor (PET positive volume) and out delineated. The spatial distribution of 48 failures in patients with complete clinical response after (chemo)radiation is used to derive a model for tumor control probability (TCP). The total TCP is fixed to the clinically observed 70% actuarial TCP at five years. Additionally, the authors match the distribution of failures between the five subvolumes to the observed distribution. The steepness of the dose–response is extracted from the literature and the authors assume 30% and 20% risk of subclinical involvement in the elective volumes. The result is a five-compartment dose response model matching the observed distribution of failures. The model is used to optimize the distribution of dose in individual patients, while keeping the treatment intensity constant and the maximum prescribed dose below 85 Gy.Results: The vast majority of failures occur centrally despite the small volumes of the central regions. Thus, optimizing the dose prescription yields higher doses to the central target volumes and lower doses to the elective volumes. The dose planning study shows that the modified prescription is clinically feasible. The optimized TCP is 89% (range: 82%–91%) as compared to the observed TCP of 70%.Conclusions: The observed distribution of locoregional failures was used to derive an objective, data-driven dose prescription function. The optimized dose is predicted to result in a substantial increase in local control without increasing the predicted risk of toxicity.

  15. Switching From Age-Based Stimulus Dosing to Dose Titration Protocols in Electroconvulsive Therapy: Empirical Evidence for Better Patient Outcomes With Lower Peak and Cumulative Energy Doses.

    Science.gov (United States)

    O'Neill-Kerr, Alex; Yassin, Anhar; Rogers, Stephen; Cornish, Janie

    2017-09-01

    The aim of this study was to test the proposition that adoption of a dose titration protocol may be associated with better patient outcomes, at lower treatment dose, and with comparable cumulative dose to that in patients treated using an age-based stimulus dosing protocol. This was an analysis of data assembled from archived records and based on cohorts of patients treated respectively on an age-based stimulus dosing protocol and on a dose titration protocol in the National Health Service in England. We demonstrated a significantly better response in the patient cohort treated with dose titration than with age-based stimulus dosing. Peak doses were less and the total cumulative dose was less in the dose titration group than in the age-based stimulus dosing group. Our findings are consistent with superior outcomes in patients treated using a dose titration protocol when compared with age-based stimulus dosing in a similar cohort of patients.

  16. Hanford Environmental Dose Reconstruction Project monthly report

    Energy Technology Data Exchange (ETDEWEB)

    Finch, S.M. [comp.

    1991-10-01

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doeses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): Source terms; environmental transport; environmental monitoring data; demographics, agriculture, food habits; environmental pathways and dose estimates.

  17. Converting low dose radiation to redox signaling

    OpenAIRE

    Pristov, Jelena Bogdanović; Spasić, Mihajlo; Spasojević, Ivan

    2013-01-01

    In contrast to the damaging effects of high doses, low dose radiation (UV, gamma) has been reported to provoke constructive changes in plants. However, the mechanisms by which plants recognize and respond to low dose radiation are not understood. We have shown recently that polygalacturonic acid, cell wall polysaccharide, converts the highly reactive product of radiation - hydroxyl radical into superoxide which may be further dismutated to hydrogen peroxide. Superoxide has been proposed to ac...

  18. 3D-printed surface mould applicator for high-dose-rate brachytherapy

    Science.gov (United States)

    Schumacher, Mark; Lasso, Andras; Cumming, Ian; Rankin, Adam; Falkson, Conrad B.; Schreiner, L. John; Joshi, Chandra; Fichtinger, Gabor

    2015-03-01

    In contemporary high-dose-rate brachytherapy treatment of superficial tumors, catheters are placed in a wax mould. The creation of current wax models is a difficult and time consuming proces.The irradiation plan can only be computed post-construction and requires a second CT scan. In case no satisfactory dose plan can be created, the mould is discarded and the process is repeated. The objective of this work was to develop an automated method to replace suboptimal wax moulding. We developed a method to design and manufacture moulds that guarantee to yield satisfactory dosimetry. A 3D-printed mould with channels for the catheters designed from the patient's CT and mounted on a patient-specific thermoplastic mesh mask. The mould planner was implemented as an open-source module in the 3D Slicer platform. Series of test moulds were created to accommodate standard brachytherapy catheters of 1.70mm diameter. A calibration object was used to conclude that tunnels with a diameter of 2.25mm, minimum 12mm radius of curvature, and 1.0mm open channel gave the best fit for this printer/catheter combination. Moulds were created from the CT scan of thermoplastic mesh masks of actual patients. The patient-specific moulds have been visually verified to fit on the thermoplastic meshes. The masks were visually shown to fit onto the thermoplastic meshes, next the resulting dosimetry will have to be compared with treatment plans and dosimetry achieved with conventional wax moulds in order to validate our 3D printed moulds.

  19. Neutrons in active proton therapy. Parameterization of dose and dose equivalent

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Uwe; Haelg, Roger A. [Univ. of Zurich (Switzerland). Dept. of Physics; Radiotherapy Hirslanden AG, Aarau (Switzerland); Lomax, Tony [Paul Scherrer Institute, Villigen (Switzerland). Center for Proton Therapy

    2017-08-01

    One of the essential elements of an epidemiological study to decide if proton therapy may be associated with increased or decreased subsequent malignancies compared to photon therapy is an ability to estimate all doses to non-target tissues, including neutron dose. This work therefore aims to predict for patients using proton pencil beam scanning the spatially localized neutron doses and dose equivalents. The proton pencil beam of Gantry 1 at the Paul Scherrer Institute (PSI) was Monte Carlo simulated using GEANT. Based on the simulated neutron dose and neutron spectra an analytical mechanistic dose model was developed. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed model in order to calculate the neutron component of the delivered dose distribution for each treated patient. The neutron dose was estimated for two patient example cases. The analytical neutron dose model represents the three-dimensional Monte Carlo simulated dose distribution up to 85 cm from the proton pencil beam with a satisfying precision. The root mean square error between Monte Carlo simulation and model is largest for 138 MeV protons and is 19% and 20% for dose and dose equivalent, respectively. The model was successfully integrated into the PSI treatment planning system. In average the neutron dose is increased by 10% or 65% when using 160 MeV or 177 MeV instead of 138 MeV. For the neutron dose equivalent the increase is 8% and 57%. The presented neutron dose calculations allow for estimates of dose that can be used in subsequent epidemiological studies or, should the need arise, to estimate the neutron dose at any point where a subsequent secondary tumour may occur. It was found that the neutron dose to the patient is heavily increased with proton energy.

  20. SU-E-I-33: Advances in Dose Metrics and Dose Reduction Strategies for Interventional Fluoroscopy.

    Science.gov (United States)

    Weir, V; Zhang, J; Bruner, A

    2012-06-01

    To explore recent advances in available dose metrics and dose reduction features and their impacts during various fluoroscopy procedures. Besides traditional dose metrics (cumulative dose, DAP, etc), recent methods such as real time dose mapping and dose calculation from DICOM information and their relevance to entrance skin exposure (ESE) are demonstrated. Dose reduction features and their potential effects on ESE are explored for different interventional procedures, including dose setting options, frame rate settings, wedges, software options and how these help reduce patient dose, etc. Real time dose monitoring techniques such as DoseAware are investigated. Dose alert such as flagging higher doses at about half of the Joint Commission sentinel event limit, Dose Index Registry and their impacts are discussed. Habit related practices, such as a physician leaning over patients, are highlighted, also taking foot off the fluoroscopy pedal when not needed, and best places to stand are illustrated. A practice improvement procedure involving measurement, analysis and improvement actions is instituted. We also discuss the impact of physician follow up letters to patients who might not have reached the JC Sentinel Event limits but may still have skin issues. In our institutes, these efforts have led to reduction of both patient dose and personnel exposure for interventional procedures. The recording of technical parameters and fluoroscopy dose by the staff has led to a better understanding of appropriate dose levels and technique settings for each procedure. This article can serve as a refresher for radiological staff on how to protect patients and themselves from high doses, while providing the best care possible. It can also serve as criteria for health care providers to institute changes and make quality improvement in interventional practices. © 2012 American Association of Physicists in Medicine.

  1. Dose reconstruction modeling for medical radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yeong Chull; Cha, Eun Shil; Lee, Won Jin [Dept. of Preventive Medicine, Korea University, Seoul (Korea, Republic of)

    2017-04-15

    Exposure information is a crucial element for the assessment of health risk due to radiation. Radiation doses received by medical radiation workers have been collected and maintained by public registry since 1996. Since exposure levels in the remote past are greater concern, it is essential to reconstruct unmeasured doses in the past using known information. We developed retrodiction models for different groups of medical radiation workers and estimate individual past doses before 1996. Reconstruction models for past radiation doses received by medical radiation workers were developed, and the past doses were estimated. Using these estimates, organ doses should be calculated which, in turn, will be used to explore a wide range of health risks of medical occupational radiation exposure. Reconstruction models for past radiation doses received by medical radiation workers were developed, and the past doses were estimated. Using these estimates, organ doses should be calculated which, in turn, will be used to explore a wide range of health risks of medical occupational radiation exposure.

  2. Reduction of extremity dose in the radiopharmacy.

    Science.gov (United States)

    Mackenzie, A

    1997-06-01

    With the future introduction of legislation originating from ICRP60 in mind, the operating procedures for the radiopharmacy were reviewed, with the intention of reducing extremity radiation dose. The radiopharmacist's index fingertip dose was measured using TLDs. The radiopharmacist received a mean dose of 0.7 mSv per 10 GBq of administered activity for the right (non-dominant hand) index finger and 0.2 mSv per 10 GBq for the left (dominant hand) index finger. These doses were comparable with other publications. The radiopharmacist received the largest part of the radiation dose during the preparation of 99Tc(m)-MDP. During this preparation, the saline was withdrawn into a syringe already containing 99Tc(m)-eluate, which results in a dose to the fingers. The technique was changed so that the saline and 99Tc(m)-eluate were withdrawn and injected separately into a MDP kit. This reduced the right finger radiation dose to 0.4 mSv per 10 GBq, while the left finger radiation dose remained at 0.2 mSv per 10 GBq. This shows that radiation doses can be effectively reduced using simple changes in procedure.

  3. Hanford Environmental Dose Reconstruction Project Monthly Report

    Energy Technology Data Exchange (ETDEWEB)

    Finch, S.M. (comp.)

    1991-03-01

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). The project is divided into the technical tasks which correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environment monitoring data; demographics, agriculture, food habits; and environmental pathways and dose estimates. 3 figs., 2 tabs.

  4. Leaf-, panel- and latex-expressed sequenced tags from the rubber tree (Hevea brasiliensis) under cold-stressed and suboptimal growing conditions: the development of gene-targeted functional markers for stress response.

    Science.gov (United States)

    Silva, Carla C; Mantello, Camila C; Campos, Tatiana; Souza, Livia M; Gonçalves, Paulo S; Souza, Anete P

    2014-01-01

    Hevea brasiliensis is a native species of the Amazon Basin of South America and the primary source of natural rubber worldwide. Due to the occurrence of South American Leaf Blight disease in this area, rubber plantations have been extended to suboptimal regions. Rubber tree breeding is time-consuming and expensive, but molecular markers can serve as a tool for early evaluation, thus reducing time and costs. In this work, we constructed six different cDNA libraries with the aim of developing gene-targeted molecular markers for the rubber tree. A total of 8,263 reads were assembled, generating 5,025 unigenes that were analyzed; 912 expressed sequence tags (ESTs) represented new transcripts, and two sequences were highly up-regulated by cold stress. These unigenes were scanned for microsatellite (SSR) regions and single nucleotide polymorphisms (SNPs). In total, 169 novel EST-SSR markers were developed; 138 loci were polymorphic in the rubber tree, and 98 % presented transferability to six other Hevea species. Locus duplication was observed in H. brasiliensis and other species. Additionally, 43 SNP markers in 13 sequences that showed similarity to proteins involved in stress response, latex biosynthesis and developmental processes were characterized. cDNA libraries are a rich source of SSR and SNP markers and enable the identification of new transcripts. The new markers developed here will be a valuable resource for linkage mapping, QTL identification and other studies in the rubber tree and can also be used to evaluate the genetic variability of other Hevea species, which are valuable assets in rubber tree breeding.

  5. Applicability of OSL pre-dose phenomenon of quartz in the estimation of equivalent dose

    Energy Technology Data Exchange (ETDEWEB)

    Koul, D.K., E-mail: dkkoul@barc.gov.i [Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Chougaonkar, M.P. [Environmental Assessment Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Polymeris, G.S. [Archaeometry Laboratory, Cultural and Educational Technology Institute, R.C. ' Athena' , Tsimiski 58, GR-67100, Xanthi (Greece)

    2010-01-15

    The feasibility of utilizing the pre-dosed OSL signal in the estimation of the equivalent dose has been investigated. The results based on (i) the behavior of growth curve, (ii) dose recovery tests and (iii) non-bleachability of reservoir centres, R-centres, suggests that (i) the pre-dosed OSL does not seem to work satisfactorily in dose estimation unlike the pre-dosed 110 deg. C TL emission and (ii) it may not be applicable in case of bleached specimen.

  6. Red bone marrow doses, integral absorbed doses, and somatically effective dose equivalent from four maxillary occlusal projections.

    Science.gov (United States)

    Berge, T I; Wøhni, T

    1984-02-01

    Phantom measurements of red bone marrow (RBM) doses, integral absorbed doses, and somatically effective dose equivalent (SEDE) from four different maxillary occlusal projections are presented. For each projection, different combinations of focus-skin distances and tube potentials were compared with regard to the patient's radiation load. The axial incisal view produced the highest patient exposures, with a maximum red bone marrow dose of 122.5 microGy/exposure, integral absorbed dose of 8.6 mJ/exposure, and SEDE values of 39.6 microSv/exposure. The corresponding values from the frontal, lateral occlusal, and tuber views ranged between 4% and 44% of the axial incisal view values for the integral absorbed dose and SEDE values, and between 0.3% and 3% for the red bone marrow doses. Increasing the focus-skin distance from 17.5 cm to 27 cm is accompanied by a 24% to 30% reduction in integral absorbed dose. Increasing the tube potential from 50 kV to 65 kV likewise results in a 23% reduction in absorbed energy.

  7. Estimate Of Reference Effective Dose And Renal Dose During Abdominal CT Scan For Dose Optimization Procedures In Ghana

    Directory of Open Access Journals (Sweden)

    Issahaku Shirazu

    2015-08-01

    Full Text Available The study is to estimate renal and effective dose during abdominal MDCT scan using image data for dose optimization for purposes of radiation protection in Ghana. In addition dose influencing parameters including CTDIVOL DLP and MSAD were recorded and compared with ICRPICRU AAPM EU and IAEA dose optimization recommendations. All the measurements were done during abdominal MDCT examination. The measured parameters were part of image data on the MeVisLab DICOM application software platform. The total photon fluence mAs per area and the photon energy fluence kVp per area on the abdominal and renal surface was also determined. Renal and effective dose were estimated using ICRP publication 103 recommendations. The results of the measured parameters based on the average renal surface area of 29.52cm2 and 30.67cm2 for the right and left kidney respectively shows that The mean dose parameters were 6.33mGy 7.78mGy 936.25mGy cm 5.76mGy 10.99mSv and 14.09mSv for CTDIV CTDIW DLP MSAD RD and E respectively. The average values were lower than the general recommended average critical values but this seems misleading based on the fact that 37 of the individual dose and exposure parameters exceeded the recommended critical values. A tradeoff between patient radiation dose and image quality in abdominal CT has been established. Where at a mean SNR of 6.6 decibels an adequate images were produce to answer all the clinical questions with an average effective dose of 14.09mSv and renal dose of 10.99mSv. Radiation dose during x-ray CT imaging is an important patient safety concern. Reducing radiation dose result in a reduction of the risk to patient however reducing dose also reduces the signal strength and thereby reduces the signal to noise ratio in the resulting CT image hence the image quality is affected. It is recommended that the established reference values be use as clinical advisory mechanism to protect patience and clinicians. It is also recommended that

  8. Case Example of Dose Optimization Using Data From Bortezomib Dose-Finding Clinical Trials.

    Science.gov (United States)

    Lee, Shing M; Backenroth, Daniel; Cheung, Ying Kuen Ken; Hershman, Dawn L; Vulih, Diana; Anderson, Barry; Ivy, Percy; Minasian, Lori

    2016-04-20

    The current dose-finding methodology for estimating the maximum tolerated dose of investigational anticancer agents is based on the cytotoxic chemotherapy paradigm. Molecularly targeted agents (MTAs) have different toxicity profiles, which may lead to more long-lasting mild or moderate toxicities as well as to late-onset and cumulative toxicities. Several approved MTAs have been poorly tolerated during long-term administration, leading to postmarketing dose optimization studies to re-evaluate the optimal treatment dose. Using data from completed bortezomib dose-finding trials, we explore its toxicity profile, optimize its dose, and examine the appropriateness of current designs for identifying an optimal dose. We classified the toxicities captured from 481 patients in 14 bortezomib dose-finding studies conducted through the National Cancer Institute Cancer Therapy Evaluation Program, computed the incidence of late-onset toxicities, and compared the incidence of dose-limiting toxicities (DLTs) among groups of patients receiving different doses of bortezomib. A total of 13,008 toxicities were captured: 46% of patients' first DLTs and 88% of dose reductions or discontinuations of treatment because of toxicity were observed after the first cycle. Moreover, for the approved dose of 1.3 mg/m(2), the estimated cumulative incidence of DLT was > 50%, and the estimated cumulative incidence of dose reduction or treatment discontinuation because of toxicity was nearly 40%. When considering the entire course of treatment, the approved bortezomib dose exceeds the conventional ceiling DLT rate of 20% to 33%. Retrospective analysis of trial data provides an opportunity for dose optimization of MTAs. Future dose-finding studies of MTAs should take into account late-onset toxicities to ensure that a tolerable dose is identified for future efficacy and comparative trials. © 2016 by American Society of Clinical Oncology.

  9. Dose-ranging design and analysis methods to identify the minimum effective dose (MED).

    Science.gov (United States)

    Zhou, Yijie; Chen, Su; Sullivan, Danielle; Li, Yihan; Zhang, Ying; Xie, Wangang; Zhang, Hongtao; Tang, Yuanyuan; Wang, Li; Hartford, Alan; Yang, Bo

    2017-12-01

    In dose ranging clinical trials, it is critical to investigate the dose-response profile and to identify a minimum effective dose (MED) to guide the dose selection for phase 3 confirmatory trials. Traditional dose ranging trials focus on pairwise comparisons between placebo and each investigational dose, while in recent years MCP-Mod (Multiple Comparison Procedures & Modeling) arose and gained popularity in the design and analysis of dose ranging trials. Comprehensive comparison between MCP-Mod and other methods have been made on continuous variables assuming a normal distribution. In this article, we extend the comparison to binary/binomial response variables. Via simulation, the rate of correct and incorrect MED identification are compared for Dunnett's test, trend test and MCP-Mod for a variety of underlying dose response profiles including both monotone and non-monotone dose responses and are compared under a large number of trial design settings. The precision of MED estimation using MCP-Mod is also evaluated comparing the design options of more dose levels and smaller sample size per dose versus fewer dose levels and larger sample size per dose. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Comparison of TID Effects in Space-Like Variable Dose Rates and Constant Dose Rates

    Science.gov (United States)

    Harris, Richard D.; McClure, Steven S.; Rax, Bernard G.; Evans, Robin W.; Jun, Insoo

    2008-01-01

    The degradation of the LM193 dual voltage comparator has been studied at different TID dose rate profiles, including several different constant dose rates and a variable dose rate that simulates the behavior of a solar flare. A comparison of results following constant dose rate vs. variable dose rates is made to explore how well the constant dose rates used for typical part testing predict the performance during a simulated space-like mission. Testing at a constant dose rate equal to the lowest dose rate seen during the simulated flare provides an extremely conservative estimate of the overall amount of degradation. A constant dose rate equal to the average dose rate is also more conservative than the variable rate. It appears that, for this part, weighting the dose rates by the amount of total dose received at each rate (rather than the amount of time at each dose rate) results in an average rate that produces an amount of degradation that is a reasonable approximation to that received by the variable rate.

  11. Low-dose versus standard-dose CT protocol in patients with clinically suspected renal colic.

    Science.gov (United States)

    Poletti, Pierre-Alexandre; Platon, Alexandra; Rutschmann, Olivier T; Schmidlin, Franz R; Iselin, Christophe E; Becker, Christoph D

    2007-04-01

    The purpose of our study was to compare a low-dose abdominal CT protocol, delivering a dose of radiation close to the dose delivered by abdominal radiography, with standard-dose unenhanced CT in patients with suspected renal colic. One hundred twenty-five patients (87 men, 38 women; mean age, 45 years) who were admitted with suspected renal colic underwent both abdominal low-dose CT (30 mAs) and standard-dose CT (180 mAs). Low-dose CT and standard-dose CT were independently reviewed, in a delayed fashion, by two radiologists for the characterization of renal and ureteral calculi (location, size) and for indirect signs of renal colic (renal enlargement, pyeloureteral dilatation, periureteral or renal stranding). Results reported for low-dose CT, with regard to the patients' body mass indexes (BMIs), were compared with those obtained with standard-dose CT (reference standard). The presence of non-urinary tract-related disorders was also assessed. Informed consent was obtained from all patients. In patients with a BMI 3 mm. Low-dose CT was 100% sensitive and specific for depicting non-urinary tract-related disorders (n = 6). Low-dose CT achieves sensitivities and specificities close to those of standard-dose CT in assessing the diagnosis of renal colic, depicting ureteral calculi > 3 mm in patients with a BMI < 30, and correctly identifying alternative diagnoses.

  12. The use of modified single pencil beam dose kernels to improve IMRT dose calculation accuracy.

    Science.gov (United States)

    Bergman, Alanah M; Otto, Karl; Duzenli, Cheryl

    2004-12-01

    Intensity modulated radiation therapy (IMRT) is used to deliver highly conformal radiation doses to tumors while sparing nearby sensitive tissues. Discrepancies between calculated and measured dose distributions have been reported for regions of high dose gradients corresponding to complex radiation fluence patterns. For the single pencil beam convolution dose calculation algorithm, the ability to resolve areas of high dose structure is partly related to the shape of the pencil beam dose kernel (similar to how a photon detector's point spread function relates to imaging resolution). Improvements in dose calculation accuracy have been reported when the treatment planning system (TPS) is recommissioned using high-resolution measurement data as input. This study proposes to improve the dose calculation accuracy for IMRT planning by modifying clinical dose kernel shapes already present in the TPS, thus avoiding the need to reacquire higher resolution commissioning data. The in-house optimization program minimizes a cost-function based on a two-dimensional composite dose subtraction/distance-to-agreement (gamma) analysis. The final modified kernel shapes are reintroduced into the treatment planning system and improvements to the dose calcula tion accuracy for complex IMRT dose distributions evaluated. The central kernel value (radius =0 cm) has the largest effect on the dose calculation resolution and is the focus of this study.

  13. Calculation of midplane dose for total body irradiation from entrance and exit dose MOSFET measurements.

    Science.gov (United States)

    Satory, P R

    2012-03-01

    This work is the development of a MOSFET based surface in vivo dosimetry system for total body irradiation patients treated with bilateral extended SSD beams using PMMA missing tissue compensators adjacent to the patient. An empirical formula to calculate midplane dose from MOSFET measured entrance and exit doses has been derived. The dependency of surface dose on the air-gap between the spoiler and the surface was investigated by suspending a spoiler above a water phantom, and taking percentage depth dose measurements (PDD). Exit and entrances doses were measured with MOSFETs in conjunction with midplane doses measured with an ion chamber. The entrance and exit doses were combined using an exponential attenuation formula to give an estimate of midplane dose and were compared to the midplane ion chamber measurement for a range of phantom thicknesses. Having a maximum PDD at the surface simplifies the prediction of midplane dose, which is achieved by ensuring that the air gap between the compensator and the surface is less than 10 cm. The comparison of estimated midplane dose and measured midplane dose showed no dependence on phantom thickness and an average correction factor of 0.88 was found. If the missing tissue compensators are kept within 10 cm of the patient then MOSFET measurements of entrance and exit dose can predict the midplane dose for the patient.

  14. Irrigation in dose assessments models

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla; Barkefors, Catarina [Studsvik RadWaste AB, Nykoeping (Sweden)

    2004-05-01

    SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

  15. Multicriteria optimization of the spatial dose distribution

    Energy Technology Data Exchange (ETDEWEB)

    Schlaefer, Alexander [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562, Germany and Institute of Medical Technology, Hamburg University of Technology, Hamburg 21073 (Germany); Viulet, Tiberiu [Medical Robotics Group, Universität zu Lübeck, Lübeck 23562 (Germany); Muacevic, Alexander; Fürweger, Christoph [European CyberKnife Center Munich, Munich 81377 (Germany)

    2013-12-15

    Purpose: Treatment planning for radiation therapy involves trade-offs with respect to different clinical goals. Typically, the dose distribution is evaluated based on few statistics and dose–volume histograms. Particularly for stereotactic treatments, the spatial dose distribution represents further criteria, e.g., when considering the gradient between subregions of volumes of interest. The authors have studied how to consider the spatial dose distribution using a multicriteria optimization approach.Methods: The authors have extended a stepwise multicriteria optimization approach to include criteria with respect to the local dose distribution. Based on a three-dimensional visualization of the dose the authors use a software tool allowing interaction with the dose distribution to map objectives with respect to its shape to a constrained optimization problem. Similarly, conflicting criteria are highlighted and the planner decides if and where to relax the shape of the dose distribution.Results: To demonstrate the potential of spatial multicriteria optimization, the tool was applied to a prostate and meningioma case. For the prostate case, local sparing of the rectal wall and shaping of a boost volume are achieved through local relaxations and while maintaining the remaining dose distribution. For the meningioma, target coverage is improved by compromising low dose conformality toward noncritical structures. A comparison of dose–volume histograms illustrates the importance of spatial information for achieving the trade-offs.Conclusions: The results show that it is possible to consider the location of conflicting criteria during treatment planning. Particularly, it is possible to conserve already achieved goals with respect to the dose distribution, to visualize potential trade-offs, and to relax constraints locally. Hence, the proposed approach facilitates a systematic exploration of the optimal shape of the dose distribution.

  16. Fewer Doses of HPV Vaccine Result in Immune Response Similar to Three-Dose Regimen

    Science.gov (United States)

    ... Press Releases NCI News Note Fewer doses of HPV vaccine result in immune response similar to three- ... report that two doses of a human papillomavirus (HPV) vaccine, trademarked as Cervarix, resulted in similar serum ...

  17. Absorbed radiation dose on LHC interconnects

    CERN Document Server

    Versaci, R; Vlachoudis, V; CERN. Geneva. ATS Department

    2011-01-01

    Here we present the results of our FLUKA simulations devoted to the evaluation of the peak dose absorbed by the busbar insulator in the LHC Interaction Region 7 interconnects. The peak dose absorbed by the cold magnet coils are also presented.

  18. Prediction ofamikacin dose requiretnents in neutropenic patients ...

    African Journals Online (AJOL)

    Prediction ofamikacin dose requiretnents in neutropenic patients with haetnatological disease. C. S. ZENT, R. ALLIN, P. I. FOLB. Abstract This study reports on the use of an easily applied. Bayesian forecasting ptogranune (OPT; Clyde- soft) to predict atnikacin dose requirements in 10 patients with haematological disease ...

  19. Low doses effects and gamma radiations low dose rates; Les effets des faibles doses et des faibles debits de doses de rayons gamma

    Energy Technology Data Exchange (ETDEWEB)

    Averbeck, D. [Institut Curie, CNRS UMR 2027, 75 - Paris (France)

    1999-07-01

    This expose wishes for bringing some definitions and base facts relative to the problematics of low doses effects and low dose rates effects. It shows some already used methods and some actual experimental approaches by focusing on the effects of ionizing radiations with a low linear energy transfer. (N.C.)

  20. An updated dose assessment for Rongelap Island

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Bogen, K.T.

    1994-07-01

    We have updated the radiological dose assessment for Rongelap Island at Rongelap Atoll using data generated from field trips to the atoll during 1986 through 1993. The data base used for this dose assessment is ten fold greater than that available for the 1982 assessment. Details of each data base are presented along with details about the methods used to calculate the dose from each exposure pathway. The doses are calculated for a resettlement date of January 1, 1995. The maximum annual effective dose is 0.26 mSv y{sup {minus}1} (26 mrem y{sup {minus}1}). The estimated 30-, 50-, and 70-y integral effective doses are 0.0059 Sv (0.59 rem), 0.0082 Sv (0.82 rem), and 0.0097 Sv (0.97 rem), respectively. More than 95% of these estimated doses are due to 137-Cesium ({sup 137}Cs). About 1.5% of the estimated dose is contributed by 90-Strontium ({sup 90}Sr), and about the same amount each by 239+240-Plutonium ({sup 239+240}PU), and 241-Americium ({sup 241}Am).

  1. Antiproton radiotherapy: peripheral dose from secondary neutrons

    DEFF Research Database (Denmark)

    Fahimian, Benjamin P.; DeMarco, John J.; Keyes, Roy

    2009-01-01

    is the normal tissue dose resulting from secondary neutrons produced in the annihilation of antiprotons on the nucleons of the target atoms. Here we present the first organ specific Monte Carlo calculations of normal tissue equivalent neutron dose in antiproton therapy through the use of a segmented CT...

  2. Low dose intravaginal misoprostol versus intracervical balloon ...

    African Journals Online (AJOL)

    Background:The efficacy and safety of low dose misoprostol as a ripening agent compared to the widely used balloon catheter in developing countries is undetermined. Objective:To compare the safety and efficacy of a low dose intravaginal misoprostol and intracervical Foley's catheter for cervical ripening. Design:A ...

  3. Dose mapping for documentation of radiation sterilization

    DEFF Research Database (Denmark)

    Miller, A.

    1999-01-01

    The radiation sterilization standards EN 552 and ISO 11137 require that dose mapping in real or simulated product be carried in connection with the process qualification. This paper reviews the recommendations given in the standards and discusses the difficulties and limitations of practical dose...

  4. A new method for effective dose calculation based on the ambient dose height distribution

    Directory of Open Access Journals (Sweden)

    Liebmann Mario

    2017-09-01

    Full Text Available The realistic determination of effective dose of the staff in diagnostic radiology has been a challenge both for personal dosimetry and ambient dose measurement. A model for dosimetry of occupational exposure is presented that allows direct determination of effective dose from measured or even manufacturer given ambient dose distribution in front of the personnel. This model considers a wide range of radiation energies, different radiation protection situations, and gender effects.

  5. Hanford Environmental Dose Reconstruction Project Monthly Report

    Energy Technology Data Exchange (ETDEWEB)

    Finch, S.M. (comp.)

    1990-05-01

    This monthly report summarizes the technical progress and project status for the Hanford Environmental Dose Reconstruction (HEDR) Project being conducted at Pacific Northwest Laboratory (PNL) under the direction of a Technical Steering Panel (TSP). The TSP is composed of experts in numerous technical fields related to this project and represents the interests of the public. The US Department of Energy (DOE) funds the project. The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks address each of the primary steps in the path from radioactive releases to dose estimates source terms, environmental transport, environmental monitoring data, demographics, agriculture, and food habits, and environmental pathways and dose estimates.

  6. Pediatric Dosing and Body Size in Biotherapeutics

    Directory of Open Access Journals (Sweden)

    Hartmut Derendorf

    2010-12-01

    Full Text Available Although pediatric doses for biotherapeutics are often based on patients' body weight (mg/kg or body surface area (mg/m2, linear body size dose adjustment is highly empirical. Growth and maturity are also important factors that affect the absorption, distribution, metabolism and excretion (ADME of biologics in pediatrics. The complexity of the factors involved in pediatric pharmacokinetics lends to the reconsideration of body size based dose adjustment. A proper dosing adjustment for pediatrics should also provide less intersubject variability in the pharmacokinetics and/or pharmacodynamics of the product compared with no dose adjustment. Biological proteins and peptides generally share the same pharmacokinetic principle with small molecules, but the underlying mechanism can be very different. Here, pediatric and adult pharmacokinetic parameters are compared and summarized for selected biotherapeutics. The effect of body size on the pediatric pharmacokinetics for these biological products is discussed in the current review.

  7. Dose reduction at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J.W.; Dionne, B.J.

    1983-01-01

    The collective dose equivalent at nuclear power plants increased from 1250 rem in 1969 to nearly 54,000 rem in 1980. This rise is attributable primarily to an increase in nuclear generated power from 1289 MW-y to 29,155 MW-y; and secondly, to increased average plant age. However, considerable variation in exposure occurs from plant to plant depending on plant type, refueling, maintenance, etc. In order to understand the factors influencing these differences, an investigation was initiated to study dose-reduction techniques and effectiveness of as low as reasonably achievable (ALARA) planning at light water plants. Objectives are to: identify high-dose maintenance tasks and related dose-reduction techniques; investigate utilization of high-reliability, low-maintenance equipment; recommend improved radioactive waste handling equipment and procedures; examine incentives for dose reduction; and compile an ALARA handbook.

  8. Radiation Dose and Image Quality of Low-dose Protocol in Chest CT: Comparison of Standard-dose Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Jeong [Occupational Lung Diseases Institute, KCOMWEL, Seoul (Korea, Republic of); Ahn, Bong Seon; Park, Young Sun [Department of Radiological Technology, Daejeon Health Science College, Daejeon (Korea, Republic of)

    2012-06-15

    The purpose of this study was to compare radiation dose and image quality between low-dose (LDP) and standard-dose protocol (SDP). LDP (120 kVp, 30 mAs, 2-mm thickness) and SDP (120 kVp, 180 mAs, 1.2-mm thickness) images obtained from 61 subjects were retrospectively evaluated at level of carina bifurcation, using multi-detector CT (Brilliance 16, Philips Medical Systems). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated at ascending aorta and infraspinatus muscle, from CT number and back-ground noise. Radiation dose from two protocols measured at 5-point using acrylic-phantom, and CT number and noise measured at 4-point using water-phantom. All statistical analysis were performed using SPSS 19.0 program. LDP images showed significantly more noise and a significantly lower SNR and CNR than did SDP images at ascending aorta and infraspinatus muscle. Noise, SNR and CNR were significantly correlated with body mass index (p<0.001). Radiation dose, SNR and CNR from phantom were significant differences between two protocols. LDP showed a significant reduction of radiation dose with a significant change in SNR and CNR compared with SDP. Therefore, exposure dose on LDP in clinical applications needs resetting highly more considering image quality.

  9. Effect of dose and dosing rate on the mutagenesis of nitric oxide in ...

    African Journals Online (AJOL)

    Effect of dose and dosing rate on the mutagenesis of nitric oxide in supF shuttle vector. Ji Hye Kim1 and ... Purpose: To determine how the dose and rate of NO• treatment affects mutagenic responses. Methods: Shuttle vector pSP189 was ... form a strong oxidant and nitrating agent, peroxynitrite (ONOO-), which can initiate.

  10. Assessment of a new p-Mosfet usable as a dose rate insensitive gamma dose sensor

    Energy Technology Data Exchange (ETDEWEB)

    Vettese, F.; Donichak, C.; Bourgeault, P. [DGA/Centre d`etudes du Bouchet/DPN, 31 - Toulouse (France)

    1995-12-31

    Dosimetric response of unbiased MOS devices has been assessed at dose rates greater than 2000 cGy/h. Application have been made to a personal dosemeter / dose rate meter to measure the absorbed tissue dose received in the case of acute external irradiation. (D.L.). 10 refs.

  11. Optimizing dose prescription in stereotactic body radiotherapy for lung tumours using Monte Carlo dose calculation

    NARCIS (Netherlands)

    Widder, Joachim; Hollander, Miranda; Ubbels, Jan F.; Bolt, Rene A.; Langendijk, Johannes A.

    Purpose: To define a method of dose prescription employing Monte Carlo (MC) dose calculation in stereotactic body radiotherapy (SBRT) for lung tumours aiming at a dose as low as possible outside of the PTV. Methods and materials: Six typical T1 lung tumours - three small, three large - were

  12. Antimicrobial Doses in Continuous Renal Replacement Therapy: A Comparison of Dosing Strategies

    Directory of Open Access Journals (Sweden)

    Anna P. Kempke

    2016-01-01

    Full Text Available Purpose. Drug dose recommendations are not well defined in patients undergoing continuous renal replacement therapy (CRRT due to limited published data. Several guidelines and pharmacokinetic equations have been proposed as tools for CRRT drug dosing. Dose recommendations derived from these methods have yet to be compared or prospectively evaluated. Methods. A literature search of PubMed, Micromedex, and Embase was conducted for 40 drugs commonly used in the ICU to gather pharmacokinetic data acquired from patients with acute and chronic kidney disease as well as healthy volunteers. These data and that obtained from drug package inserts were gathered for use in three published CRRT drug dosing equations. Doses calculated for a model patient using each method were compared to doses suggested in a commonly used dosing text. Results. Full pharmacokinetic data was available for 18, 31, and 40 agents using acute kidney injury, end stage renal disease, and normal patient data, respectively. On average, calculated doses differed by 30% or more from the doses recommended by the renal dosing text for >50% of the medications. Conclusion. Wide variability in dose recommendations for patients undergoing CRRT exists when these equations are used. Alternate, validated dosing methods need to be developed for this at-risk patient population.

  13. Antimicrobial Doses in Continuous Renal Replacement Therapy: A Comparison of Dosing Strategies.

    Science.gov (United States)

    Kempke, Anna P; Leino, Abbie S; Daneshvar, Farzad; Lee, John Andrew; Mueller, Bruce A

    2016-01-01

    Purpose. Drug dose recommendations are not well defined in patients undergoing continuous renal replacement therapy (CRRT) due to limited published data. Several guidelines and pharmacokinetic equations have been proposed as tools for CRRT drug dosing. Dose recommendations derived from these methods have yet to be compared or prospectively evaluated. Methods. A literature search of PubMed, Micromedex, and Embase was conducted for 40 drugs commonly used in the ICU to gather pharmacokinetic data acquired from patients with acute and chronic kidney disease as well as healthy volunteers. These data and that obtained from drug package inserts were gathered for use in three published CRRT drug dosing equations. Doses calculated for a model patient using each method were compared to doses suggested in a commonly used dosing text. Results. Full pharmacokinetic data was available for 18, 31, and 40 agents using acute kidney injury, end stage renal disease, and normal patient data, respectively. On average, calculated doses differed by 30% or more from the doses recommended by the renal dosing text for >50% of the medications. Conclusion. Wide variability in dose recommendations for patients undergoing CRRT exists when these equations are used. Alternate, validated dosing methods need to be developed for this at-risk patient population.

  14. Patient radiation exposure in uterine artery embolization of leiomyomata: calculation of organ doses and effective dose

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, S.; Strecker, E.P. [Department of Radiology, Diakonissenkrankenhaus, Diakonissenstrasse 28, 76199, Karlsruhe (Germany); Schultz, F.W.; Zoetelief, J. [Interfaculty Reactor Institute, Medical Physics, Delft University of Technology, 2629 JB, Delft (Netherlands)

    2004-05-01

    The goal of this study was estimation of patient effective dose from uterine artery embolization of leiomyomata. Parameters and data relevant to patient dose were recorded for 33 consecutive procedures. Using Monte Carlo simulation of radiation transport, organ and effective doses were calculated in detail for a subset of five procedures, to estimate the effective dose for all procedures. Mean dose area product was 59.9, median 23.4, and range 8.8-317.5 Gycm{sup 2}. Mean absorbed ovarian dose was calculated as 51 mGy in the five procedures. Using the dose conversion factor estimated from the Monte Carlo simulation for all procedures a mean estimated effective dose of 34 mSv (median 13 mSv, range 5-182 mSv) results, with a tendency to lower values regarding the succession of the procedures. Patients' radiation exposure level is up to twice of that of an abdominal CT examination. Angiographic equipment related dose-reducing features and radiographic technique essentially influence organ doses and effective dose. Consistent application of dose-reducing techniques and awareness of radiation exposure justifies uterine artery embolization as a therapeutic option for the treatment of uterine fibroids. (orig.)

  15. Fixed Dosing of Monoclonal Antibodies in Oncology.

    Science.gov (United States)

    Hendrikx, Jeroen J M A; Haanen, John B A G; Voest, Emile E; Schellens, Jan H M; Huitema, Alwin D R; Beijnen, Jos H

    2017-10-01

    Most monoclonal antibodies in oncology are administered in body-size-based dosing schedules. This is believed to correct for variability in both drug distribution and elimination between patients. However, monoclonal antibodies typically distribute to the blood plasma and extracellular fluids only, which increase less than proportionally with the increase in body weight. Elimination takes place via proteolytic catabolism, a nonspecific immunoglobulin G elimination pathway, and intracellular degradation after binding to the target. The latter is the primary route of elimination and is related to target expression levels rather than body size. Taken together, the minor effects of body size on distribution and elimination of monoclonal antibodies and their usually wide therapeutic window do not support body-size-based dosing. We evaluated effects of body weight on volume of distribution and clearance of monoclonal antibodies in oncology and show that a fixed dose for most of these drugs is justified based on pharmacokinetics. A survey of the savings after fixed dosing of monoclonal antibodies at our hospital showed that fixed dosing can reduce costs of health care, especially when pooling of preparations is not possible (which is often the case in smaller hospitals). In conclusion, based on pharmacokinetic parameters of monoclonal antibodies, there is a rationale for fixed dosing of these drugs in oncology. Therefore, we believe that fixed dosing is justified and can improve efficiency of the compounding. Moreover, drug spillage can be reduced and medication errors may become less likely. The currently available knowledge of elimination of monoclonal antibodies combined with the publicly available data from clinical trials and extensive population pharmacokinetic (PopPK) modeling justifies fixed dosing. Interpatient variation in exposure is comparable after body weight and fixed dosing and most monoclonal antibodies show relatively flat dose-response relationships

  16. Geração de planos de produção via otimização seqüencial subótima Providing production plans via suboptimal sequential optimization

    Directory of Open Access Journals (Sweden)

    Oscar Salviano Silva Filho

    2007-01-01

    Full Text Available Neste artigo são discutidos aspectos relacionados à tomada de decisão dentro de um processo hierárquico de planejamento da produção. Neste contexto, foi desenvolvido um modelo agregado para um problema de planejamento estocástico, com restrições de chances nas variáveis de decisão, que serve como meta de produção a ser atingida nos níveis inferiores da hierarquia. Solução ótima global para este tipo de problema seqüencial é muito difícil, a menos em casos de pequena dimensão via algoritmo de programação dinâmica estocástica. Assim, como alternativa, investigou-se a utilização de uma heurística subótima denominada open-loop feedback controller (OLFC, que é muito simples de ser implementada computacionalmente. Como exemplo de aplicação, um problema mono-produto de planejamento agregado da produção foi formulado e a política subótima OLFC foi comparada à solução ótima usando o algoritmo de programação dinâmica estocástica. Além dos aspectos numéricos, algumas propriedades são analisadas, como a quase adaptabilidade do procedimento OLFC.In this paper, the need for developing an aggregate production plan within a hierarchical decision process is discussed. A production planning problem formulated as a sequential stochastic optimal control model with chance constraints is introduced. A global optimal solution is only possible in particular cases with a small number of decision variables. As a consequence, near optimal solutions are usually developed and applied to solve sequential stochastic problems. A suboptimal approach, called Open-Loop Feedback Controller (OLFC, is proposed to solve the aggregate stochastic production planning problem. A simple example is used to evaluate the performance of the OLFC solution computationally in relation to the global (closed-loop and mean (open-loop optimal solutions. Quasi-adaptability property of the OLFC procedure is analysed in this example.

  17. Implications of nonuniform tumor doses for radioimmunotherapy.

    Science.gov (United States)

    O'Donoghue, J A

    1999-08-01

    This article describes a method of assessing the biologic consequences of nonuniform dose distributions produced in tumors by biologically targeted radionuclide therapy. The analysis is based on a simple mathematical model that assumes all tumor cells are uniformly radiosensitive. Using the linear-quadratic radiobiologic model, it is possible to represent an absorbed dose distribution by a biologically effective dose (BED) volume histogram (BVH). The Laplace transform of the BVH yields an equivalent uniform biologically effective dose. This is a one-number value that fully describes the biologic effect of a nonuniform absorbed dose distribution. In this article, for the purposes of exposition, nonuniform BED distributions are represented by normal distributions. Nonuniform absorbed dose distributions are inefficient in sterilizing tumors and become proportionately less effective as the mean dose increases. The loss in effectiveness is most severe for radiosensitive tumors. Several approaches may alleviate the consequences of dosimetric nonuniformity. These include the use of smaller targeting molecules, radionuclides with longer emission ranges, fractionated administration of biologically targeted radionuclide therapy and combined modality treatments.

  18. Variation in lunar neutron dose estimates.

    Science.gov (United States)

    Slaba, Tony C; Blattnig, Steve R; Clowdsley, Martha S

    2011-12-01

    The radiation environment on the Moon includes albedo neutrons produced by primary particles interacting with the lunar surface. In this work, HZETRN2010 is used to calculate the albedo neutron contribution to effective dose as a function of shielding thickness for four different space radiation environments and to determine to what extent various factors affect such estimates. First, albedo neutron spectra computed with HZETRN2010 are compared to Monte Carlo results in various radiation environments. Next, the impact of lunar regolith composition on the albedo neutron spectrum is examined, and the variation on effective dose caused by neutron fluence-to-effective dose conversion coefficients is studied. A methodology for computing effective dose in detailed human phantoms using HZETRN2010 is also discussed and compared. Finally, the combined variation caused by environmental models, shielding materials, shielding thickness, regolith composition and conversion coefficients on the albedo neutron contribution to effective dose is determined. It is shown that a single percentage number for characterizing the albedo neutron contribution to effective dose can be misleading. In general, the albedo neutron contribution to effective dose is found to vary between 1-32%, with the environmental model, shielding material and shielding thickness being the driving factors that determine the exact contribution. It is also shown that polyethylene or other hydrogen-rich materials may be used to mitigate the albedo neutron exposure.

  19. Topical Metered-dosing Dispenser Performance Evaluation.

    Science.gov (United States)

    Liu, Qiang; Kupiec, Thomas C; Vu, Nicole T

    2016-01-01

    Topical metered-dosing dispensers are designed for dosing accuracy and ease-of-use by the patients while protecting the packaged products from environmental exposure and contamination. The objective of this study was to evaluate the accuracy, precision, and residual of available topical metered-dosing dispensers with different types of topical cream for practical application. Triplicate samples of five different dispensers were tested. This test was completed using three types of commercial topical cream-bases of dissimilar Total Active Pharmaceutical Ingredient Load Percentages, Transdermal Penetration Percentages, and Specific Gravities. The dispensers were evaluated according to specified dose-uniformity criteria for a total dispensing capacity of 30 mL at 0.5 mL per dose for 60 doses. The study shows Topi-CLICK performed with the best precision and accuracy of dosing in comparison to the airless-pump type dispensers. While the dispensing was highly variable with airless pumps and may require calibration for each packaged product, remarkably the performance of Topi-CLICK was not affected by different types of cream-bases and does not require additional metering calibration. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

  20. Brachytherapy dose measurements in heterogeneous tissues

    Energy Technology Data Exchange (ETDEWEB)

    Paiva F, G.; Luvizotto, J.; Salles C, T.; Guimaraes A, P. C.; Dalledone S, P. de T.; Yoriyaz, H. [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Rubo, R., E-mail: gabrielpaivafonseca@gmail.com [Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, 05403-900 Sao Paulo (Brazil)

    2014-08-15

    Recently, Beau lieu et al. published an article providing guidance for Model-Based Dose Calculation Algorithms (MBDCAs), where tissue heterogeneity considerations are addressed. It is well-known that T G-43 formalism which considers only water medium is limited and significant dose differences have been found comparing both methodologies. The aim of the present work is to experimentally quantify dose values in heterogeneous medium using different dose measurement methods and techniques and compare them with those obtained with Monte Carlo simulations. Experiments have been performed using a Nucletron micro Selectron-Hdr Ir-192 brachytherapy source and a heterogeneous phantom composed by PMMA and different tissue equivalent cylinders like bone, lungs and muscle. Several dose measurements were obtained using tissue equivalent materials with height 1.8 cm and 4.3 cm positioned between the radiation source and the detectors. Radiochromic films, TLDs and MOSFET S have been used for the dose measurements. Film dosimetry has been performed using two methodologies: a) linearization for dose-response curve based on calibration curves to create a functional form that linearize s the dose response and b) 177 multichannel analysis dosimetry where the multiple color channels are analyzed allowing to address not only disturbances in the measurements caused by thickness variation in the film layer, but also, separate other external influences in the film response. All experiments have been simulated using the MCNP5 Monte Carlo radiation transport code. Comparison of experimental results are in good agreement with calculated dose values with differences less than 6% for almost all cases. (Author)

  1. Dosing of Enoxaparin in Renal Impairment.

    Science.gov (United States)

    Shaikh, Suhail A; Regal, Randolph E

    2017-04-01

    To review enoxaparin treatment dosing, pharmacokinetics, and clinical outcomes data in patients with renal impairment and to examine the current two-tiered dosing regimen approved by the Food and Drug Administration (FDA). A literature search of PubMed (1990-2016) was performed using the search terms low-molecular-weight heparin, unfractionated heparin, bleeding, enoxaparin, renal impairment, pharmacokinetics, and hemodialysis. All studies assessing the pharmacokinetic properties of enoxaparin in patients with renal impairment were evaluated. In addition, all retrospective and prospective studies assessing the safety and efficacy of enoxaparin treatment in this population were evaluated. Five pharmacokinetic studies evaluated changes in the pharmacokinetics of enoxaparin in patients with renal impairment. In these studies, enoxaparin clearance was reduced by 17% to 44% in patients with mild and moderate renal impairment. Six retrospective studies evaluated the safety of enoxaparin in patients with renal impairment. In one study, patients with moderate renal impairment were at increased risk of bleeding when using the current FDA-approved two-tiered scheme (odds ratio, 4.7; 95% confidence interval, 1.7-13.0; P = 0.002). Another study demonstrated that individualized enoxaparin dosing, when compared to FDA-approved dosing, resulted in a decreased risk of bleeding. Two retrospective studies evaluated efficacy. One of these studies compared reduced-dose enoxaparin with unfractionated heparin; there was a trend toward lower incidences of thromboembolism and 30-day mortality with reduced-dose enoxaparin. Hospital length of stay also decreased with reduced-dosed enoxaparin. This paper highlights the differences in the pharmacokinetic properties and safety and efficacy outcomes in multiple degrees of renal impairment when using treatment-dose enoxaparin. Given the literature highlighted in this review, a more multitiered enoxaparin renal dosing strategy-perhaps shifting

  2. Eye lens dose in interventional cardiology.

    Science.gov (United States)

    Principi, S; Delgado Soler, C; Ginjaume, M; Beltran Vilagrasa, M; Rovira Escutia, J J; Duch, M A

    2015-07-01

    The ICRP has recently recommended reducing the occupational exposure dose limit for the lens of the eye to 20 mSv y(-1), averaged over a period of 5 y, with no year exceeding 50 mSv, instead of the current 150 mSv y(-1). This reduction will have important implications for interventional cardiology and radiology (IC/IR) personnel. In this work, lens dose received by a staff working in IC is studied in order to determine whether eye lens dose monitoring or/and additional radiological protection measures are required. Eye lens dose exposure was monitored in 10 physicians and 6 nurses. The major IC procedures performed were coronary angiography and percutaneous transluminal coronary angioplasty. The personnel were provided with two thermoluminescent dosemeters (TLDs): one calibrated in terms of Hp(3) located close to the left ear of the operator and a whole-body dosemeter calibrated in terms of Hp(10) and Hp(0.07) positioned on the lead apron. The estimated annual eye lens dose for physicians ranged between 8 and 60 mSv, for a workload of 200 procedures y(-1). Lower doses were collected for nurses, with estimated annual Hp(3) between 2 and 4 mSv y(-1). It was observed that for nurses the Hp(0.07) measurement on the lead apron is a good estimate of eye lens dose. This is not the case for physicians, where the influence of both the position and use of protective devices such as the ceiling shield is very important and produces large differences among doses both at the eyes and on the thorax. For physicians, a good correlation between Hp(3) and dose area product is shown. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Dose rate effect on low-dose hyper-radiosensitivity with cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Geon-Min; Kim, Eun-Hee [Seoul National University, Seoul (Korea, Republic of)

    2016-10-15

    Low-dose hyper-radiosensitivity (HRS) is the phenomenon that mammalian cells exhibit higher sensitivity to radiation at low doses (< 0.5 Gy) than expected by the linear-quadratic model. At doses above 0.5Gy, the cellular response is recovered to the level expected by the linear-quadratic model. This transition is called the increased radio-resistance (IRR). HRS was first verified using Chinese hamster V79 cells in vitro by Marples and has been confirmed in studies with other cell lines including human normal and tumor cells. HRS is known to be induced by inactivation of ataxia telangiectasia-mutated (ATM), which plays a key role in repairing DNA damages. Considering the connection between ATM and HRS, one can infer that dose rate may affect cellular response regarding HRS at low doses. In this study, we quantitated the effect of dose rate on HRS by clonogenic assay with normal and tumor cells. The HRS of cells at low dose exposures is a phenomenon already known. In this study, we observed HRS of rat normal diencephalon cells and rat gliosarcoma cells at doses below 1 Gy. In addition, we found that dose rate mattered. HRS occurred at low doses, but only when total dose was delivered at a rate below certain level.

  4. A conversion coefficient from dose-area products to effective doses for patients in intraoral radiography

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Kenji; Yosue, Takashi [Nippon Dental Univ., Tokyo (Japan); Sakaino, Rie; Harata, Yasuo [Showa Univ., Tokyo (Japan). School of Dentistry

    2002-06-01

    A conversion coefficient from dose-area products to effective doses was proposed as a practical estimator of patient health detriments from intraoral radiography. According to the tissue-dose data reported by Gibbs et al. (Dentomaxillofac. Radiol., 1987 and 1988) and the tissue weighting factors recommended in ICRP Publication 60, the effective doses and the dose-area products were calculated at 70, 80, and 90 kV for E-speed films employed at each of seven geometries using bisecting angle, paralleling, and bitewing techniques with round or rectangular collimated beams. The focus-skin distances were 20 cm for the short cone and 40 cm for the long cone, respectively. From a total of 90 sets of exposure factors in intraoral radiographic examinations for adults, the effective doses were in the range of 0.38 {mu}Sv to 8.0 {mu}Sv, and the corresponding dose-area products were 0.58 cGy{center_dot}cm{sup 2} and 7.6 cGy{center_dot}cm{sup 2}. The obtained linear regression coefficient to convert the dose-area product to the effective dose was 0.97 {mu}Sv/cGy{center_dot}cm{sup 2}. We conclude that effective doses can be estimated from the dose-area products if an uncertainty of a factor of two is acceptable in intraoral radiography. (author)

  5. Dose integration and dose rate characteristics of a NiPAM polymer gel MRI dosimeter system

    Science.gov (United States)

    Waldenberg, C.; Karlsson Hauer, A.; Gustafsson, C.; Ceberg, S.

    2017-05-01

    The normoxic polymer gel dosimeter based on N-isopropyl acrylamide (NiPAM) is a promising full 3D-dosimeter with high spatial resolution and near tissue equivalency. NiPAM gel samples were irradiated to different doses using a linear accelerator. The absorbed dose was evaluated using MRI and statistical significance of the analysed data was calculated. The analysis was carried out using an in-house developed software. It was found that the gel dosimeter responded linearly to the absorbed dose. The gel exhibited a dose rate dependence, as well as a dependence on the sequential beam irradiation scheme. A higher dose rate, as well as a higher dose per sequential beam, resulted in a lower dose response.

  6. Mercury dosing solutions for fluorescent lamps

    Science.gov (United States)

    Corazza, A.; Boffito, C.

    2008-07-01

    A review of the different technologies used to dose mercury in fluorescent lamps is presented. Conventional liquid mercury dosing is gradually being replaced with more reliable and environmentally friendly solutions that enable a significant reduction of the amount of mercury introduced in the lamp, so as to cope with more stringent regulations issued to minimize the environmental impact of exhausted lamps. This paper will review the most advanced novel methods to assure an accurate and fine dosing of mercury in fluorescent lamps, especially focusing on solutions based on the use of solid alloys.

  7. Topology optimization of inertia driven dosing units

    DEFF Research Database (Denmark)

    Andreasen, Casper Schousboe

    2017-01-01

    This paper presents a methodology for optimizing inertia driven dosing units, sometimes referred to as eductors, for use in small scale flow applications. The unit is assumed to operate at low to moderate Reynolds numbers and under steady state conditions. By applying topology optimization...... to the Brinkman penalized Navier-Stokes equation the design of the dosing units can be optimized with respect to dosing capability without initial design assumptions. The influence of flow resistance and speed is investigated to assess design performance under varying operating conditions....

  8. Absorbed dose by a CMOS in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Borja H, C. G.; Valero L, C. Y.; Guzman G, K. A.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Paredes G, L. C., E-mail: candy_borja@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-10-15

    Absorbed dose by a complementary metal oxide semiconductor (CMOS) circuit as part of a pacemaker, has been estimated using Monte Carlo calculations. For a cancer patient who is a pacemaker carrier, scattered radiation could damage pacemaker CMOS circuits affecting patient's health. Absorbed dose in CMOS circuit due to scattered photons is too small and therefore is not the cause of failures in pacemakers, but neutron calculations shown an absorbed dose that could cause damage in CMOS due to neutron-hydrogen interactions. (Author)

  9. Location Modification Factors for Potential Dose Estimation

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, Sandra F.; Barnett, J. Matthew

    2017-01-01

    A Department of Energy facility must comply with the National Emission Standard for Hazardous Air Pollutants for radioactive air emissions. The standard is an effective dose of less than 0.1 mSv yr-1 to the maximum public receptor. Additionally, a lower dose level may be assigned to a specific emission point in a State issued permit. A method to efficiently estimate the expected dose for future emissions is described. This method is most appropriately applied to a research facility with several emission points with generally low emission levels of numerous isotopes.

  10. FUEL HANDLING FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    A. Achudume

    2004-08-09

    The purpose of this design calculation is to estimate radiation doses received by personnel working in the Fuel Handling Facility (FHF) of the Monitored Geological Repository (MGR). The FHF is a surface facility supporting waste handling operations i.e. receive transportation casks, transfer wastes, prepare waste packages, and ship out loaded waste packages and empty casks. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation. The results are also limited to normal operations only. Results of this calculation will be used to support the FHF design and License Application.

  11. CANISTER HANDLING FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    D.T. Dexheimer

    2004-02-27

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Canister Handling Facility (CHF) performing operations to receive transportation casks, transfer wastes, prepare waste packages, perform associated equipment maintenance. The specific scope of work contained in this calculation covers individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation. The results of this calculation will be used to support the design of the CHF and provide occupational dose estimates for the License Application.

  12. Mercury dosing solutions for fluorescent lamps

    Energy Technology Data Exchange (ETDEWEB)

    Corazza, A; Boffito, C [SAES Getters S.p.A., Viale Italia 77, Lainate (MI) 20020 (Italy)], E-mail: alessio_corazza@saes-group.com

    2008-07-21

    A review of the different technologies used to dose mercury in fluorescent lamps is presented. Conventional liquid mercury dosing is gradually being replaced with more reliable and environmentally friendly solutions that enable a significant reduction of the amount of mercury introduced in the lamp, so as to cope with more stringent regulations issued to minimize the environmental impact of exhausted lamps. This paper will review the most advanced novel methods to assure an accurate and fine dosing of mercury in fluorescent lamps, especially focusing on solutions based on the use of solid alloys.

  13. Influence of Genotype on Warfarin Maintenance Dose Predictions Produced Using a Bayesian Dose Individualization Tool.

    Science.gov (United States)

    Saffian, Shamin M; Duffull, Stephen B; Roberts, Rebecca L; Tait, Robert C; Black, Leanne; Lund, Kirstin A; Thomson, Alison H; Wright, Daniel F B

    2016-12-01

    A previously established Bayesian dosing tool for warfarin was found to produce biased maintenance dose predictions. In this study, we aimed (1) to determine whether the biased warfarin dose predictions previously observed could be replicated in a new cohort of patients from 2 different clinical settings, (2) to explore the influence of CYP2C9 and VKORC1 genotype on predictive performance of the Bayesian dosing tool, and (3) to determine whether the previous population used to develop the kinetic-pharmacodynamic model underpinning the Bayesian dosing tool was sufficiently different from the test (posterior) population to account for the biased dose predictions. The warfarin maintenance doses for 140 patients were predicted using the dosing tool and compared with the observed maintenance dose. The impact of genotype was assessed by predicting maintenance doses with prior parameter values known to be altered by genetic variability (eg, EC50 for VKORC1 genotype). The prior population was evaluated by fitting the published kinetic-pharmacodynamic model, which underpins the Bayesian tool, to the observed data using NONMEM and comparing the model parameter estimates with published values. The Bayesian tool produced positively biased dose predictions in the new cohort of patients (mean prediction error [95% confidence interval]; 0.32 mg/d [0.14-0.5]). The bias was only observed in patients requiring ≥7 mg/d. The direction and magnitude of the observed bias was not influenced by genotype. The prior model provided a good fit to our data, which suggests that the bias was not caused by different prior and posterior populations. Maintenance doses for patients requiring ≥7 mg/d were overpredicted. The bias was not due to the influence of genotype nor was it related to differences between the prior and posterior populations. There is a need for a more mechanistic model that captures warfarin dose-response relationship at higher warfarin doses.

  14. Validation of GPU based TomoTherapy dose calculation engine.

    Science.gov (United States)

    Chen, Quan; Lu, Weiguo; Chen, Yu; Chen, Mingli; Henderson, Douglas; Sterpin, Edmond

    2012-04-01

    The graphic processing unit (GPU) based TomoTherapy convolution/superposition(C/S) dose engine (GPU dose engine) achieves a dramatic performance improvement over the traditional CPU-cluster based TomoTherapy dose engine (CPU dose engine). Besides the architecture difference between the GPU and CPU, there are several algorithm changes from the CPU dose engine to the GPU dose engine. These changes made the GPU dose slightly different from the CPU-cluster dose. In order for the commercial release of the GPU dose engine, its accuracy has to be validated. Thirty eight TomoTherapy phantom plans and 19 patient plans were calculated with both dose engines to evaluate the equivalency between the two dose engines. Gamma indices (Γ) were used for the equivalency evaluation. The GPU dose was further verified with the absolute point dose measurement with ion chamber and film measurements for phantom plans. Monte Carlo calculation was used as a reference for both dose engines in the accuracy evaluation in heterogeneous phantom and actual patients. The GPU dose engine showed excellent agreement with the current CPU dose engine. The majority of cases had over 99.99% of voxels with Γ(1%, 1 mm) GPU dose engine also showed similar degree of accuracy in heterogeneous media as the current TomoTherapy dose engine. It is verified and validated that the ultrafast TomoTherapy GPU dose engine can safely replace the existing TomoTherapy cluster based dose engine without degradation in dose accuracy.

  15. Randomized pharmacokinetic evaluation of different rifabutin doses in African HIV- infected tuberculosis patients on lopinavir/ritonavir-based antiretroviral therapy.

    Science.gov (United States)

    Naiker, Suhashni; Connolly, Cathy; Wiesner, Lubbe; Kellerman, Tracey; Reddy, Tarylee; Harries, Anthony; McIlleron, Helen; Lienhardt, Christian; Pym, Alexander

    2014-11-19

    Pharmacokinetic interactions between rifampicin and protease inhibitors (PIs) complicate the management of HIV-associated tuberculosis. Rifabutin is an alternative rifamycin, for patients requiring PIs. Recently some international guidelines have recommended a higher dose of rifabutin (150 mg daily) in combination with boosted lopinavir (LPV/r), than the previous dose of rifabutin (150 mg three times weekly {tiw}). But there are limited pharmacokinetic data evaluating the higher dose of rifabutin in combination with LPV/r. Sub-optimal dosing can lead to acquired rifamycin resistance (ARR). The plasma concentration of 25-O-desacetylrifabutin (d-RBT), the metabolite of rifabutin, increases in the presence of PIs and may lead to toxicity. Sixteen patients with TB-HIV co-infection received rifabutin 300 mg QD in combination with tuberculosis chemotherapy (initially pyrazinamide, isoniazid and ethambutol then only isoniazid), and were then randomized to receive isoniazid and LPV/r based ART with rifabutin 150 mg tiw or rifabutin 150 mg daily. The rifabutin dose with ART was switched after 1 month. Serial rifabutin and d-RBT concentrations were measured after 4 weeks of each treatment. The median AUC0-48 and Cmax of rifabutin in patients taking 150 mg rifabutin tiw was significantly reduced compared to the other treatment arms. Geometric mean ratio (90% CI) for AUC0-48 and Cmax was 0.6 (0.5-0.7) and 0.5 (0.4-0.6) for RBT 150 mg tiw compared with RBT 300 mg and 0.4 (0.4-0.4) and 0.5 (0.5-0.6) for RBT 150 mg tiw compared with 150 mg daily. 86% of patients on the tiw rifabutin arm had an AUC0-24 ART, and grade 3 neutropenia (asymptomatic) was reported in 4 patients. These events were not associated with increases in rifabutin or metabolite concentrations. A daily 150 mg dose of rifabutin in combination with LPV/r safely maintained rifabutin plasma concentrations in line with those shown to prevent ARR. ClinicalTrials.gov Identifier: NCT00640887.

  16. Precision Hypofractionated Radiation Therapy in Poor Performing Patients With Non-Small Cell Lung Cancer: Phase 1 Dose Escalation Trial

    Energy Technology Data Exchange (ETDEWEB)

    Westover, Kenneth D. [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Loo, Billy W. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Gerber, David E. [Division of Hematology-Oncology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Iyengar, Puneeth; Choy, Hak [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Diehn, Maximilian [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Hughes, Randy; Schiller, Joan; Dowell, Jonathan [Division of Hematology-Oncology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Wardak, Zabi [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Sher, David [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States); Christie, Alana; Xie, Xian-Jin [Department of Clinical Science, Southwestern Medical Center, Dallas, Texas (United States); Corona, Irma [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Sharma, Akanksha [School of Medicine, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Wadsworth, Margaret E. [Radiation Oncology of Mississippi, Jackson, Mississippi (United States); Timmerman, Robert, E-mail: Robert.Timmerman@utsouthwestern.edu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)

    2015-09-01

    Purpose: Treatment regimens for locally advanced non-small cell lung cancer (NSCLC) give suboptimal clinical outcomes. Technological advancements such as radiation therapy, the backbone of most treatment regimens, may enable more potent and effective therapies. The objective of this study was to escalate radiation therapy to a tumoricidal hypofractionated dose without exceeding the maximally tolerated dose (MTD) in patients with locally advanced NSCLC. Methods and Materials: Patients with stage II to IV or recurrent NSCLC and Eastern Cooperative Oncology Group performance status of 2 or greater and not candidates for surgical resection, stereotactic radiation, or concurrent chemoradiation were eligible. Highly conformal radiation therapy was given to treat intrathoracic disease in 15 fractions to a total of 50, 55, or 60 Gy. Results: Fifty-five patients were enrolled: 15 at the 50-Gy, 21 at the 55-Gy, and 19 at the 60-Gy dose levels. A 90-day follow-up was completed in each group without exceeding the MTD. With a median follow-up of 12.5 months, there were 93 grade ≥3 adverse events (AEs), including 39 deaths, although most AEs were considered related to factors other than radiation therapy. One patient from the 55- and 60-Gy dose groups developed grade ≥3 esophagitis, and 5, 4, and 4 patients in the respective dose groups experienced grade ≥3 dyspnea, but only 2 of these AEs were considered likely related to therapy. There was no association between fraction size and toxicity (P=.24). The median overall survival was 6 months with no significant differences between dose levels (P=.59). Conclusions: Precision hypofractionated radiation therapy consisting of 60 Gy in 15 fractions for locally advanced NSCLC is generally well tolerated. This treatment regimen could provide patients with poor performance status a potent alternative to chemoradiation. This study has implications for the cost effectiveness of lung cancer therapy. Additional studies of long

  17. CT radiation dose and iterative reconstruction techniques

    National Research Council Canada - National Science Library

    Padole, Atul; Ali Khawaja, Ranish Deedar; Kalra, Mannudeep K; Singh, Sarabjeet

    2015-01-01

    .... CT image quality is dependent on the selected image reconstruction algorithm. 3. Iterative reconstruction algorithms have reemerged with the potential of radiation dose optimization by lowering image noise. 4...

  18. Hanford Environmental Dose Reconstruction Project. Monthly report

    Energy Technology Data Exchange (ETDEWEB)

    McMakin, A.H.; Cannon, S.D.; Finch, S.M. [comps.

    1992-07-01

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

  19. Hanford Environmental Dose Reconstruction Project monthly report

    Energy Technology Data Exchange (ETDEWEB)

    McMakin, A.H., Cannon, S.D.; Finch, S.M. (comps.)

    1992-09-01

    The objective of the Hanford Environmental Dose Reconstruction MDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in envirorunental pathways. epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering. radiation dosimetry. and cultural anthropology. Included are appointed members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source Terms; Environmental Transport; Environmental Monitoring Data Demography, Food Consumption, and Agriculture; and Environmental Pathways and Dose Estimates.

  20. Review of surface dose detectors in radiotherapy

    LENUS (Irish Health Repository)

    O'Shea, E.

    2006-11-20

    Several instruments have been used to measure absorbed radiation dose under non-electronic equilibrium conditions, such as in the build-up region or near the interface between two different media, including the surface. Many of these detectors are discussed in this paper. A common method of measuring the absorbed dose distribution and electron contamination in the build-up region of high-energy beams for radiation therapy is by means of parallel-plate ionisation chambers. Thermoluminescent dosimeters (TLDs), diodes and radiographic film have also been used to obtain surface dose measurements. The diamond detector was used recently by the author in an investigation on the effects of beam-modifying devices on skin dose and it is also described in this report

  1. Effective dose: a radiation protection quantity

    CERN Document Server

    Menzel, H G

    2012-01-01

    Modern radiation protection is based on the principles of justification, limitation, and optimisation. Assessment of radiation risks for individuals or groups of individuals is, however, not a primary objective of radiological protection. The implementation of the principles of limitation and optimisation requires an appropriate quantification of radiation exposure. The International Commission on Radiological Protection (ICRP) has introduced effective dose as the principal radiological protection quantity to be used for setting and controlling dose limits for stochastic effects in the regulatory context, and for the practical implementation of the optimisation principle. Effective dose is the tissue weighted sum of radiation weighted organ and tissue doses of a reference person from exposure to external irradiations and internal emitters. The specific normalised values of tissue weighting factors are defined by ICRP for individual tissues, and used as an approximate age- and sex-averaged representation of th...

  2. Calculational Tool for Skin Contamination Dose Assessment

    CERN Document Server

    Hill, R L

    2002-01-01

    Spreadsheet calculational tool was developed to automate the calculations preformed for dose assessment of skin contamination. This document reports on the design and testing of the spreadsheet calculational tool.

  3. Nurse dose: what's in a concept?

    Science.gov (United States)

    Manojlovich, Milisa; Sidani, Souraya

    2008-08-01

    Many researchers have sought to address the relationship between nursing care and patient outcomes, with inconsistent and contradictory findings. We conducted a concept analysis and concept derivation, basing our work on theoretical and empirical literature, to derive nurse dose as a concept that pulls into a coherent whole disparate variables used in staffing studies. We defined nurse dose as the level of nursing reflected in the purity, amount, frequency, and duration of nursing care needed to produce favorable outcomes. All four parameters of nurse dose used together can facilitate our understanding of how nursing contributes to patient outcomes. Ongoing investigation will help to identify the parameters of nurse dose that have the greatest effect on outcomes. 2008 Wiley Periodicals, Inc

  4. Biological Effects of Low-Dose Exposure

    CERN Document Server

    Komochkov, M M

    2000-01-01

    On the basis of the two-protection reaction model an analysis of stochastic radiobiological effects of low-dose exposure of different biological objects has been carried out. The stochastic effects are the results published in the last decade: epidemiological studies of human cancer mortality, the yield of thymocyte apoptosis of mice and different types of chromosomal aberrations. The results of the analysis show that as dependent upon the nature of biological object, spontanous effect, exposure conditions and radiation type one or another form dose - effect relationship is realized: downwards concave, near to linear and upwards concave with the effect of hormesis included. This result testifies to the incomplete conformity of studied effects of 1990 ICRP recomendations based on the linear no-threshold hypothesis about dose - effect relationship. Because of this the methodology of radiation risk estimation recomended by ICRP needs more precisian and such quantity as collective dose ought to be classified into...

  5. Dipyrone and acetaminophen: correct dosing by parents?

    Directory of Open Access Journals (Sweden)

    João Guilherme Bezerra Alves

    Full Text Available CONTEXT AND OBJECTIVE: Several studies in developed countries have documented that a significant percentage of children are given inappropriate doses of acetaminophen and ibuprofen. The objective of this paper was to investigate parents’ accuracy in giving dipyrone and acetaminophen to their children, in a poor region. DESIGN AND SETTING: Cross-sectional study at the pediatric emergency department of Instituto Materno-Infantil Prof. Fernando Figueira, a teaching hospital in Pernambuco. METHODS: The inclusion criteria were age between 3 and 36 months, main complaint of fever and at least one dose of dipyrone or acetaminophen given to the child during the 24 hours preceding their arrival at the emergency department. The mothers were asked for demographic information and about the antipyretic doses given, which were compared with the recommended dosage. RESULTS: Among the 200 patients studied, 117 received dipyrone and 83 received acetaminophen. Overall, 75 % received an incorrect dose of antipyretic. Of the patients who received dipyrone, 105 (89.7% were given an incorrect dose; 16 (15.2% received too little dipyrone, and 89 (84.8% received too much. Of the patients who received acetaminophen, 45 (54.2% were given an incorrect dose; 38 (84.4% received too little acetaminophen, and 7 (15.6% received too much. There were no differences in maternal and child characteristics between the groups receiving correct and incorrect doses of medication, except for the type of medication (dipyrone versus acetaminophen. CONCLUSIONS: Most of the children treated were given inappropriate doses, mainly dipyrone overdosing and acetaminophen underdosing.

  6. Radiation Doses to Skin from Dermal Contamination

    Science.gov (United States)

    2010-10-01

    Doses to Skin From Dermal Contamination HDTRA1-07-C-0015 A. Iulian Apostoaei and David C. Kocher Prepared by: SENES Oak Ridge, Inc. Center for Risk...5a. CONTRACT NUMBER HDTRA1-07-C-0015 5b. GRANT NUMBER 4. TITLE AND SUBTITLE Radiation Doses to Skin from Dermal Contamination 5c... contamination due to a uniform deposition of airborne radioactive material in specific regions of the body. This methodology includes a model to estimate

  7. Potential radiation doses from 1994 Hanford Operations

    Energy Technology Data Exchange (ETDEWEB)

    Soldat, J.K.; Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the potential radiation doses to the public from releases originating at the Hanford Site. Members of the public are potentially exposed to low-levels of radiation from these effluents through a variety of pathways. The potential radiation doses to the public were calculated for the hypothetical MEI and for the general public residing within 80 km (50 mi) of the Hanford Site.

  8. Radiation Biology Irradiator Dose Verification Survey.

    Science.gov (United States)

    Pedersen, Kurt H; Kunugi, Keith A; Hammer, Clifford G; Culberson, Wesley S; DeWerd, Larry A

    2016-02-01

    Interest in standardized dosimetry for radiobiological irradiators has expanded over the last decade. At a symposium held at NIST, "The Importance of Standardization of Dosimetry in Radiobiology", a set of 12 criteria necessary for adequate irradiation was developed by the authors. Here we report on our review of dosimetry methods from various peer-reviewed publications and found that none of them satisfied all 12 criteria set forth by the authors of the NIAD/NCI/NIST proceedings. The inadequate reporting of dosimetry methods in the literature raises questions regarding the accuracy of the dose delivered to animal test subjects and the resulting experimental results. For this reason, we investigated the level of accuracy of dose delivery in radiation biology studies. We performed an irradiator output verification study of 12 radiation biology laboratories (7 gamma and 5 X-ray units) using polymethyl methacrylate (PMMA) mouse phantoms and thermoluminescent dosimeters (TLDs) readouts at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The laboratories housing each of these irradiators were asked to deliver specific doses to individual mouse phantoms. Simultaneously, mouse phantoms at the UWMRRC were irradiated with NIST-traceable reference beams representative of the subject laboratories' beam energies. The irradiated mouse phantoms were returned from the various institutions to the UWMRRC and the TLDs were processed, with their measured dose response compared to the known dose response of the calibration phantom TLDs. Of the five facilities using X-ray irradiators, only one delivered an output within 5% of the target dose. The dose differences for the other four X-ray irradiators ranged from 12 to 42%. These results indicate the potential need for standardization of dose determination and additional oversight of radiobiology investigations.

  9. Vancomycin Utilization Evaluation: Are We Dosing Appropriately?

    Directory of Open Access Journals (Sweden)

    Ladan Ayazkhoo

    2015-10-01

    Full Text Available Background: Inappropriate use of vancomycin not only increase health care costs but also contribute to the emergence of resistant organisms. Higher trough serum vancomycin concentrations (>10mg/L has been recommended for avoidance of development of resistance. We aim to compare the administered dose with recommended doses based on guideline-recommended weight-based dosing.Methods: In a cross sectional study, all patients who received vancomycin between July and October 2013, in infectious disease, internal medicine wards and emergency department of a teaching hospital in Tehran, Iran were entered to the study. Indication of vancomycin and necessary data for dose calculation including height and serum creatinine were recorded. Prescribed doses were compared with recommended doses in guidelines and calculated Glomerular filtration rate (GFR for each patient.Results: One hundred and four patients (45 females and 59 males recruited in the study. Our results indicated that, from all administered doses of vancomycin, 64.4% and 88.8% differs significantly (more than 20% based on American Pharmacist Association (AphA vancomycin monograph and guideline-recommended, weight-based vancomycin dosing (for adults, respectively.Conclusion: Underdosing of vancomycin is a major risk factor for developing resistance of gram positive organisms to this glycopeptide. Our results showed that more than half of patients receiving vancomycin are in the risk of low drug levels based on guidelines. So, having a comprehensive plan for the proper use of this drug especially designing effective internal guidelines can prevent emergence of resistance to vancomycin in future.

  10. Defined daily doses (DDD) do not accurately reflect opioid doses used in contemporary chronic pain treatment.

    Science.gov (United States)

    Nielsen, Suzanne; Gisev, Natasa; Bruno, Raimondo; Hall, Wayne; Cohen, Milton; Larance, Briony; Campbell, Gabrielle; Shanahan, Marian; Blyth, Fiona; Lintzeris, Nicholas; Pearson, Sallie; Mattick, Richard; Degenhardt, Louisa

    2017-05-01

    To assess how well the defined daily dose (DDD) metric reflects opioid utilisation among chronic non-cancer pain patients. Descriptive, cross-sectional study, utilising a 7-day medication diary. Community-based treatment settings, Australia. A sample of 1101 people prescribed opioids for chronic non-cancer pain. Opioid dose data was collected via a self-completed 7-day medication diary capturing names, strengths and doses of each medication taken in the past week. Median daily dose was calculated for each opioid. Comparisons were made to the World Health Organization's (WHO) DDD metric. WHO DDDs ranged from 0.6 to 7.1 times the median opioid doses used by the sample. For transdermal fentanyl and oral hydromorphone, the median dose was comparable with the DDD. The DDD for methadone was 0.6 times lower than the median doses used by this sample of chronic pain patients. In contrast, the DDD for oxycodone and transdermal buprenorphine, the most commonly used strong opioids for chronic pain in Australia, was two to seven times higher than actual doses used. For many opioids, there are key differences between the actual doses used in clinical practice and the WHO's DDDs. The interpretation of opioid utilisation studies using population-level DDDs may be limited, and a recalibration of the DDD for many opioids or the reporting of opioid utilisation in oral morphine equivalent doses is recommended. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Vancomycin Dosing in Obese Patients: Special Considerations and Novel Dosing Strategies.

    Science.gov (United States)

    Durand, Cheryl; Bylo, Mary; Howard, Brian; Belliveau, Paul

    2017-12-01

    To review the literature regarding vancomycin pharmacokinetics in obese patients and strategies used to improve dosing in this population. PubMed, EMBASE (1974 to November 2017), and Google Scholar searches were conducted using the search terms vancomycin, obese, obesity, pharmacokinetics, strategy, and dosing. Additional articles were selected from reference lists of selected studies. Included articles were those published in English with a primary focus on vancomycin pharmacokinetic parameters in obese patients and practical vancomycin dosing strategies, clinical experiences, or challenges of dosing vancomycin in this population. Volume of distribution and clearance are the pharmacokinetic parameters that most often affect vancomycin dosing in obese patients; both are increased in this population. Challenges with dosing in obese patients include inconsistent and inadequate dosing, observations that the obese population may not be homogeneous, and reports of an increased likelihood of supratherapeutic trough concentrations. Investigators have revised and developed dosing and monitoring protocols to address these challenges. These approaches improved target trough attainment to varying degrees. Some of the vancomycin dosing approaches provided promising results in obese patients, but there were notable differences in methods used to develop these approaches, and sample sizes were small. Although some approaches can be considered for validation in individual institutions, further research is warranted. This may include validating approaches in larger populations with narrower obesity severity ranges, investigating target attainment in indication-specific target ranges, and evaluating the impact of different dosing weights and methods of creatinine clearance calculation.

  12. Chinese Herbal Medicines – Comparison of Doses Prescribed in ...

    African Journals Online (AJOL)

    questionnaire included doses of frequently-used Chinese herbs, cognition of current doses in clinical practice, and doctors' (practitioners') opinions on dose levels. The median of Chinese herbal medicines' dose prescribed by the participants was compared with the upper limit value (ULV) of stipulated doses in China ...

  13. 10 CFR 20.1004 - Units of radiation dose.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Units of radiation dose. 20.1004 Section 20.1004 Energy... Units of radiation dose. (a) Definitions. As used in this part, the units of radiation dose are: Gray (Gy) is the SI unit of absorbed dose. One gray is equal to an absorbed dose of 1 Joule/kilogram (100...

  14. Radiation Leukemogenesis at Low Dose Rates

    Energy Technology Data Exchange (ETDEWEB)

    Weil, Michael; Ullrich, Robert

    2013-09-25

    The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

  15. Hanford Environmental Dose Reconstruction Project Monthly Report

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, B.S. (comp.)

    1990-02-01

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is divided into technical tasks which address each of the primary steps in the path from radioactive releases to dose estimates. Included are source terms, environmental transport, environmental monitoring data, demographics, agriculture, and food habits, and environmental pathways and dose estimates. The source terms task will develop estimates of radioactive emissions from Hanford facilities since 1944. The environmental transport task will reconstruct the movement of radioactive materials from the areas of release to populations via the atmosphere, surface water, and ground water. The environmental monitoring task will assemble, evaluate, and report historical environmental monitoring data. The demographics, agriculture, and food habits task will develop the data needed to determine the populations that could have been affected by the releases. Population and demographic information will be developed for the general population within the study area. In addition to population and demographic data, the food and water consumption patterns and sources of food and water for these populations must be estimated since these provide a primary pathway for the intake of radionuclides. The environmental pathways and dose estimates task will use the information produced by the other tasks to estimate the radiation doses populations could have received from Hanford. 1 tab., 1 fig.

  16. Carcinogenesis induced by low-dose radiation

    Directory of Open Access Journals (Sweden)

    Piotrowski Igor

    2017-11-01

    Full Text Available Although the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of low and very low radiation doses on the organism. Ionizing radiation has been shown to induce gene mutations and chromosome aberrations which are known to be involved in the process of carcinogenesis. The induction of secondary cancers is a challenging long-term side effect in oncologic patients treated with radiation. Medical sources of radiation like intensity modulated radiotherapy used in cancer treatment and computed tomography used in diagnostics, deliver very low doses of radiation to large volumes of healthy tissue, which might contribute to increased cancer rates in long surviving patients and in the general population. Research shows that because of the phenomena characteristic for low dose radiation the risk of cancer induction from exposure of healthy tissues to low dose radiation can be greater than the risk calculated from linear no-threshold model. Epidemiological data collected from radiation workers and atomic bomb survivors confirms that exposure to low dose radiation can contribute to increased cancer risk and also that the risk might correlate with the age at exposure.

  17. Dose escalation of a curcuminoid formulation

    Directory of Open Access Journals (Sweden)

    Crowell James

    2006-03-01

    Full Text Available Abstract Background Curcumin is the major yellow pigment extracted from turmeric, a commonly-used spice in India and Southeast Asia that has broad anticarcinogenic and cancer chemopreventive potential. However, few systematic studies of curcumin's pharmacology and toxicology in humans have been performed. Methods A dose escalation study was conducted to determine the maximum tolerated dose and safety of a single dose of standardized powder extract, uniformly milled curcumin (C3 Complex™, Sabinsa Corporation. Healthy volunteers were administered escalating doses from 500 to 12,000 mg. Results Seven of twenty-four subjects (30% experienced only minimal toxicity that did not appear to be dose-related. No curcumin was detected in the serum of subjects administered 500, 1,000, 2,000, 4,000, 6,000 or 8,000 mg. Low levels of curcumin were detected in two subjects administered 10,000 or 12,000 mg. Conclusion The tolerance of curcumin in high single oral doses appears to be excellent. Given that achieving systemic bioavailability of curcumin or its metabolites may not be essential for colorectal cancer chemoprevention, these findings warrant further investigation for its utility as a long-term chemopreventive agent.

  18. Radiation Dose Estimation by Automated Cytogenetic Biodosimetry.

    Science.gov (United States)

    Rogan, Peter K; Li, Yanxin; Wilkins, Ruth C; Flegal, Farrah N; Knoll, Joan H M

    2016-12-01

    The dose from ionizing radiation exposure can be interpolated from a calibration curve fit to the frequency of dicentric chromosomes (DCs) at multiple doses. As DC counts are manually determined, there is an acute need for accurate, fully automated biodosimetry calibration curve generation and analysis of exposed samples. Software, the Automated Dicentric Chromosome Identifier (ADCI), is presented which detects and discriminates DCs from monocentric chromosomes, computes biodosimetry calibration curves and estimates radiation dose. Images of metaphase cells from samples, exposed at 1.4-3.4 Gy, that had been manually scored by two reference laboratories were reanalyzed with ADCI. This resulted in estimated exposures within 0.4-1.1 Gy of the physical dose. Therefore, ADCI can determine radiation dose with accuracies comparable to standard triage biodosimetry. Calibration curves were generated from metaphase images in ~10 h, and dose estimations required ~0.8 h per 500 image sample. Running multiple instances of ADCI may be an effective response to a mass casualty radiation event. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Measurement of radiation dose in dental radiology.

    Science.gov (United States)

    Helmrot, Ebba; Alm Carlsson, Gudrun

    2005-01-01

    Patient dose audit is an important tool for quality control and it is important to have a well-defined and easy to use method for dose measurements. In dental radiology, the most commonly used dose parameters for the setting of diagnostic reference levels (DRLs) are the entrance surface air kerma (ESAK) for intraoral examinations and dose width product (DWP) for panoramic examinations. DWP is the air kerma at the front side of the secondary collimator integrated over the collimator width and an exposure cycle. ESAK or DWP is usually measured in the absence of the patient but with the same settings of tube voltage (kV), tube current (mA) and exposure time as with the patient present. Neither of these methods is easy to use, and, in addition, DWP is not a risk related quantity. A better method of monitoring patient dose would be to use a dose area product (DAP) meter for all types of dental examinations. In this study, measurements with a DAP meter are reported for intraoral and panoramic examinations. The DWP is also measured with a pencil ionisation chamber and the product of DWP and the height H (DWP x H) of the secondary collimator (measured using film) was compared to DAP. The results show that it is feasible to measure DAP using a DAP meter for both intraoral and panoramic examinations. The DAP is therefore recommended for the setting of DRLs.

  20. Radiation Dose Optimization For Critical Organs

    Science.gov (United States)

    Khodadadegan, Yasaman

    Ionizing radiation used in the patient diagnosis or therapy has negative effects on the patient body in short term and long term depending on the amount of exposure. More than 700,000 examinations are everyday performed on Interventional Radiology modalities, however; there is no patient-centric information available to the patient or the Quality Assurance for the amount of organ dose received. In this study, we are exploring the methodologies to systematically reduce the absorbed radiation dose in the Fluoroscopically Guided Interventional Radiology procedures. In the first part of this study, we developed a mathematical model which determines a set of geometry settings for the equipment and a level for the energy during a patient exam. The goal is to minimize the amount of absorbed dose in the critical organs while maintaining image quality required for the diagnosis. The model is a large-scale mixed integer program. We performed polyhedral analysis and derived several sets of strong inequalities to improve the computational speed and quality of the solution. Results present the amount of absorbed dose in the critical organ can be reduced up to 99% for a specific set of angles. In the second part, we apply an approximate gradient method to simultaneously optimize angle and table location while minimizing dose in the critical organs with respect to the image quality. In each iteration, we solve a sub-problem as a MIP to determine the radiation field size and corresponding X-ray tube energy. In the computational experiments, results show further reduction (up to 80%) of the absorbed dose in compare with previous method. Last, there are uncertainties in the medical procedures resulting imprecision of the absorbed dose. We propose a robust formulation to hedge from the worst case absorbed dose while ensuring feasibility. In this part, we investigate a robust approach for the organ motions within a radiology procedure. We minimize the absorbed dose for the critical

  1. Determining organ dose: the holy grail

    Energy Technology Data Exchange (ETDEWEB)

    Samei, Ehsan; Tian, Xiaoyu; Segars, W.P. [Duke University, Carl E. Ravin Advanced Imaging Laboratories, Departments of Radiology, Biomedical Engineering, Physics, and Electrical Engineering, Durham, NC (United States)

    2014-10-15

    Among the various metrics to quantify CT radiation dose, organ dose is generally regarded as one of the best to reflect patient radiation burden. Organ dose is dependent on two main factors, namely patient anatomy and irradiation field. An accurate estimation of organ dose requires detailed modeling of both factors. The modeling of patient anatomy needs to reflect the anatomical diversity and complexity across the population so that the attributes of a given clinical patient can be properly accounted for. The modeling of the irradiation field needs to accurately reflect the CT system condition, especially the tube current modulation (TCM) technique. We present an atlas-based method to model patient anatomy via a library of computational phantoms with representative ages, sizes and genders. A clinical patient is matched with a corresponding computational phantom to obtain a representation of patient anatomy. The irradiation field of the CT system is modeled using a validated Monte Carlo simulation program. The tube current modulation profiles are simulated using a manufacturer-generalizable ray-tracing algorithm. Combining the patient model, Monte Carlo results, and TCM profile, organ doses are obtained by multiplying organ dose values from a fixed mA scan (normalized to CTDI{sub vol}-normalized, denoted as h{sub organ}) and an adjustment factor that reflects the specific irradiation of each organ. The accuracy of the proposed method was quantified by simulating clinical abdominopelvic examinations of 58 patients. The predicted organ doses showed good agreement with simulated organ dose across all organs and modulation schemes. For an average CTDI{sub vol} of a CT exam of 10 mGy, the absolute median error across all organs was 0.64 mGy (-0.21 and 0.97 for 25th and 75th percentiles, respectively). The percentage differences were within 15%. The study demonstrates that it is feasible to estimate organ doses in clinical CT examinations for protocols without and with

  2. dose in cervical cancer intracavitary brachytherapy

    Directory of Open Access Journals (Sweden)

    Zahra Siavashpour

    2016-04-01

    Full Text Available Purpose: To analyze the optimum organ filling point for organs at risk (OARs dose in cervical cancer high-dose-rate (HDR brachytherapy. Material and methods : In a retrospective study, 32 locally advanced cervical cancer patients (97 insertions who were treated with 3D conformal external beam radiation therapy (EBRT and concurrent chemotherapy during 2010-2013 were included. Rotterdam HDR tandem-ovoid applicators were used and computed tomography (CT scanning was performed after each insertion. The OARs delineation and GEC-ESTRO-based clinical target volumes (CTVs contouring was followed by 3D forward planning. Then, dose volume histogram (DVH parameters of organs were recorded and patients were classified based on their OARs volumes, as well as their inserted tandem length. Results : The absorbed dose to point A ranged between 6.5-7.5 Gy. D 0.1cm ³ and D 2cm ³ of the bladder significantly increased with the bladder volume enlargement (p value < 0.05. By increasing the bladder volume up to about 140 cm3, the rectum dose was also increased. For the cases with bladder volumes higher than 140 cm3, the rectum dose decreased. For bladder volumes lower than 75 cm3, the sigmoid dose decreased; however, for bladder volumes higher than 75 cm3, the sigmoid dose increased. The D 2cm ³ of the bladder and rectum were higher for longer tandems than for shorter ones, respectively. The divergence of the obtained results for different tandem lengths became wider by the extension of the bladder volume. The rectum and sigmoid volume had a direct impact on increasing their D 0.1cm ³ and D 2cm ³, as well as decreasing their D 10 , D 30 , and D 50 . Conclusions : There is a relationship between the volumes of OARs and their received doses. Selecting a bladder with a volume of about 70 cm3 or less proved to be better with regards to the dose to the bladder, rectum, and sigmoid.

  3. Organ dose and effective dose with the EOS scanner in spine deformity surgery

    DEFF Research Database (Denmark)

    Heide Pedersen, Peter; Eiskjær, Søren Peter; Petersen, Asger Greval

    2016-01-01

    Organ dose and effective dose with the EOS scanner in spine deformity surgery. A study on anthropomorphic phantoms describing patient radiation exposure in full spine examinations. Authors: Peter Heide Pedersen, Asger Greval Petersen, Søren Peter Eiskjær. Background: Ionizing radiation potentially...... leads to tissue damage. It has been documented in large cohort studies that radiographic imaging during childhood for spinal deformities eg. scoliosis, increases the lifetime risk of breast cancer. The EOS biplane x-ray imaging system (EOS Imaging S.A, Paris France) has been developed to produce high...... quality images while at the same time reducing radiation dose. At our institution we use the EOS for pre- and postoperative full spine examinations. Purpose: The purpose of the study is to make first time organ dose and effective dose evaluations with micro-dose settings in full spine examinations. Our...

  4. Dose Effects of Ion Beam Exposure on Deinococcus Radiodurans: Survival and Dose Response

    Science.gov (United States)

    Song, Dao-jun; Wu, Li-fang; Wu, Li-jun; Yu, Zeng-liang

    2001-02-01

    To explore the survival and dose response of organism for different radiation sources is of great importance in the research of radiobiology. In this study, the survival-dose response of Deinococcus radiodurans (E.coli, as the control) for ultra-violet (UV), γ-rays radiation and ion beam exposure was investigated. The shoulder type of survival curves were found for both UV and γ-ray ionizing radiation, but the saddle type of survival curves were shown for H+, N+(20keV and 30keV) and Ar+ beam exposure. This dose effect of the survival initially decreased with the increase in dose and then increased in the high dose range and finally decreased again in the higher dose range. Our experimental results suggest that D. radiodurans, which is considerably radio-resistant to UV and x-ray and γ-ray ionizing radiation, do not resist ion beam exposure.

  5. Radiochromic Plastic Films for Accurate Measurement of Radiation Absorbed Dose and Dose Distributions

    DEFF Research Database (Denmark)

    McLaughlin, W. L.; Miller, Arne; Fidan, S.

    1977-01-01

    Thin radiochromic dye films are useful for measuring large radiation absorbed doses (105–108 rads) and for high-resolution imaging of dose patterns produced by penetrating radiation beams passing through non-homogeneous media. Certain types of amino-substituted triarylmethane cyanides dissolved...... in polymeric solutions can be cast into flexible free-standing thin films of uniform thickness and reproducible response to ultraviolet and ionizing radiation. The increase in optical density versus energy deposited by radiation is linear over a wide range of doses and is for practical purposes independent...... of dose rate (1–1014 rad s−1). Upon irradiation of the film, the profile of the radiation field is registered as a permanent colored image of the dose distribution. Unlike most other types of dyed plastic dose meters, the optical density produced by irradiation is in most cases stable for periods...

  6. External dose-rate conversion factors for calculation of dose to the public

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    This report presents a tabulation of dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides in the environment. This report was prepared in conjunction with criteria for limiting dose equivalents to members of the public from operations of the US Department of Energy (DOE). The dose-rate conversion factors are provided for use by the DOE and its contractors in performing calculations of external dose equivalents to members of the public. The dose-rate conversion factors for external exposure to photons and electrons presented in this report are based on a methodology developed at Oak Ridge National Laboratory. However, some adjustments of the previously documented methodology have been made in obtaining the dose-rate conversion factors in this report. 42 refs., 1 fig., 4 tabs.

  7. A decision tool to adjust the prescribed dose after change in the dose calculation algorithm

    Directory of Open Access Journals (Sweden)

    Abdulhamid Chaikh

    2014-12-01

    Full Text Available Purpose: This work aims to introduce a method to quantify and assess the differences in monitor unites MUs when changing to new dose calculation software that uses a different algorithm, and to evaluate the need and extent of adjustment of the prescribed dose to maintain the same clinical results. Methods: Doses were calculated using two classical algorithms based on the Pencil Beam Convolution PBC model, using 6 patients presenting lung cancers. For each patient, 3 treatment plans were generated: Plan 1 was calculated using reference algorithm PBC without heterogeneity correction, Plan 2 was calculated using test algorithm with heterogeneity correction, and in plan 3 the dose was recalculated using test algorithm and monitor unites MUs obtained from plan 1 as input. To assess the differences in the calculated MUs, isocenter dose, and spatial dose distributions using a gamma index were compared. Statistical analysis was based on a Wilcoxon signed rank test. Results: The test algorithm in plan 2 calculated significantly less MUs than reference algorithm in plan 1 by on average 5%, (p < 0.001. We also found underestimating dose for target volumes using 3D gamma index analysis. In this example, in order to obtain the same clinical outcomes with the two algorithms the prescribed dose should be adjusted by 5%.Conclusion: This method provides a quantitative evaluation of the differences between two dose calculation algorithms and the consequences on the prescribed dose. It could be used to adjust the prescribed dose when changing calculation software to maintain the same clinical results as obtained with the former software. In particular, the gamma evaluation could be applied to any situation where changes in the dose calculation occur in radiotherapy.

  8. Evaluation of the sterility of single-dose medications used in a multiple-dose fashion.

    Science.gov (United States)

    Martin, Elizabeth P; Mukherjee, Jean; Sharp, Claire R; Sinnott-Stutzman, Virginia B

    2017-11-01

    Bacterial proliferation was evaluated in single-dose medications used in a multi-dose fashion and when medications were intentionally inoculated with bacteria. Of 5 experimentally punctured medications, 1 of 75 vials (50% dextrose) became contaminated. When intentionally inoculated, hydroxyethyl starch and heparinized saline supported microbial growth. Based on these findings, it is recommended that hydroxyethyl starch and heparinized saline not be used in a multi-dose fashion.

  9. Radiation doses in low-dose pelvimetry using rare-earth screens.

    Science.gov (United States)

    Axelsson, B; Ohlsén, H

    1979-01-01

    A 'low-dose technique' of obstetric pelvimetry, using rare-earth screens and a reduced ambition level of image quality, yields an estimated absorbed dose to the maternal and foetal gonads of 0.9 and 0.01 mGy, respectively. The resulting risk for 'hereditary ill health' and the risk for induction of leukemia from the absorbed dose to the foetal red bone marrow, have been calculated to be at a very low level.

  10. Antimicrobial Doses in Continuous Renal Replacement Therapy: A Comparison of Dosing Strategies

    OpenAIRE

    Kempke, Anna P.; Leino, Abbie S.; Daneshvar, Farzad; Lee, John Andrew; Mueller, Bruce A.

    2016-01-01

    Purpose. Drug dose recommendations are not well defined in patients undergoing continuous renal replacement therapy (CRRT) due to limited published data. Several guidelines and pharmacokinetic equations have been proposed as tools for CRRT drug dosing. Dose recommendations derived from these methods have yet to be compared or prospectively evaluated. Methods. A literature search of PubMed, Micromedex, and Embase was conducted for 40 drugs commonly used in the ICU to gather pharmacokinetic dat...

  11. Occupational Doses and the Contribution to the Population Dose in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Jae; Kyu, Hwan Jeong [KINS, Daejeon (Korea, Republic of)

    2016-05-15

    The purpose of this study is to evaluate the occupational exposure records in terms of the control of exposure for radiation workers and dose reduction. The study includes the estimates of the number of people exposed occupationally, the effective collective doses and mean doses to those exposed. In addition, the study includes an estimate of the contribution of occupational exposure to the Korean population dose. The exposure of radiation workers in occupational field includes medical radiology, industrial applications such as radiography, nuclear power, and some research activities. Occupational exposure from medical radiology practices includes the contributions from diagnostic x-ray procedures, dental radiography, nuclear medicine and radiation therapy. The control of exposure for radiation workers, and the measures necessary to maintain radiation exposure as low as reasonably achievable (ALARA) are specified in Subparagraph 3 and Subparagraph 4 of Article 91 (1) of the Korea Nuclear Safety Act (KNSA), respectively. Therefore, from a regulatory perspective, the exposure data of the workers are primarily for verification of the adequacy of the control of exposure, radiation protection and implementation of ALARA. The number of people exposed occupationally, the effective collective doses and mean doses to those exposed, and average effective doses from occupational exposure during the period of 2009 to 2013 have been evaluated. In general, radiation workers were increasing in number annually, but the mean doses for those exposed each year showed the control of exposures were mostly considered met within the dose limit in KNSA. Nevertheless, it was shown that the continuous efforts would be needed to reduce doses and thus to implement ALARA regulatory requirements. In radiation occupations, the application of ICRP radiation protection principles will ensure good practice and decreasing exposures. Over the period of 5 years, the contributions of the annual

  12. Replacing the Measles Ten-Dose Vaccine Presentation with the Single-Dose Presentation in Thailand

    OpenAIRE

    Lee, Bruce Y.; Assi, Tina-Marie; Rookkapan, Korngamon; Connor, Diana L.; Rajgopal, Jayant; Sornsrivichai, Vorasith; Brown, Shawn T.; Joel S. Welling; Bryan A. Norman; Chen, Sheng-I; Bailey, Rachel R; Wiringa, Ann E.; Wateska, Angela R.; Jana, Anirban; Willem G van Panhuis

    2011-01-01

    Introduced to minimize open vial wastage, single-dose vaccine vials require more storage space and therefore may affect vaccine supply chains (i.e., the series of steps and processes entailed to deliver vaccines from manufacturers to patients). We developed a computational model of Thailand’s Trang province vaccine supply chain to analyze the effects of switching from a ten-dose measles vaccine presentation to each of the following: a single-dose Measles-Mumps-Rubella vaccine (which Thailand ...

  13. Dose-response-a challenge for allelopathy?

    Science.gov (United States)

    Belz, Regina G; Hurle, Karl; Duke, Stephen O

    2005-04-01

    The response of an organism to a chemical depends, among other things, on the dose. Nonlinear dose-response relationships occur across a broad range of research fields, and are a well established tool to describe the basic mechanisms of phytotoxicity. The responses of plants to allelochemicals as biosynthesized phytotoxins, relate as well to nonlinearity and, thus, allelopathic effects can be adequately quantified by nonlinear mathematical modeling. The current paper applies the concept of nonlinearity to assorted aspects of allelopathy within several bioassays and reveals their analysis by nonlinear regression models. Procedures for a valid comparison of effective doses between different allelopathic interactions are presented for both, inhibitory and stimulatory effects. The dose-response applications measure and compare the responses produced by pure allelochemicals [scopoletin (7-hydroxy-6-methoxy-2H-1-benzopyran-2-one); DIBOA (2,4-dihydroxy-2H-1,4-benzoxaxin-3(4H)-one); BOA (benzoxazolin-2(3H)-one); MBOA (6-methoxy-benzoxazolin-2(3H)-one)], involved in allelopathy of grain crops, to demonstrate how some general principles of dose responses also relate to allelopathy. Hereupon, dose-response applications with living donor plants demonstrate the validity of these principles for density-dependent phytotoxicity of allelochemicals produced and released by living plants (Avena sativa L., Secale cereale L., Triticum L. spp.), and reveal the use of such experiments for initial considerations about basic principles of allelopathy. Results confirm that nonlinearity applies to allelopathy, and the study of allelopathic effects in dose-response experiments allows for new and challenging insights into allelopathic interactions.

  14. Dose-Response—A Challenge for Allelopathy?

    Science.gov (United States)

    Belz, Regina G.; Hurle, Karl; Duke, Stephen O.

    2005-01-01

    The response of an organism to a chemical depends, among other things, on the dose. Nonlinear dose-response relationships occur across a broad range of research fields, and are a well established tool to describe the basic mechanisms of phytotoxicity. The responses of plants to allelochemicals as biosynthesized phytotoxins, relate as well to nonlinearity and, thus, allelopathic effects can be adequately quantified by nonlinear mathematical modeling. The current paper applies the concept of nonlinearity to assorted aspects of allelopathy within several bioassays and reveals their analysis by nonlinear regression models. Procedures for a valid comparison of effective doses between different allelopathic interactions are presented for both, inhibitory and stimulatory effects. The dose-response applications measure and compare the responses produced by pure allelochemicals [scopoletin (7-hydroxy-6-methoxy-2H-1-benzopyran-2-one); DIBOA (2,4-dihydroxy-2H-1,4-benzoxaxin-3(4H)-one); BOA (benzoxazolin-2(3H)-one); MBOA (6-methoxy-benzoxazolin-2(3H)-one)], involved in allelopathy of grain crops, to demonstrate how some general principles of dose responses also relate to allelopathy. Hereupon, dose-response applications with living donor plants demonstrate the validity of these principles for density-dependent phytotoxicity of allelochemicals produced and released by living plants (Avena sativa L., Secale cereale L., Triticum L. spp.), and reveal the use of such experiments for initial considerations about basic principles of allelopathy. Results confirm that nonlinearity applies to allelopathy, and the study of allelopathic effects in dose-response experiments allows for new and challenging insights into allelopathic interactions. PMID:19330161

  15. Automated size-specific CT dose monitoring program: assessing variability in CT dose.

    Science.gov (United States)

    Christianson, Olav; Li, Xiang; Frush, Donald; Samei, Ehsan

    2012-11-01

    The potential health risks associated with low levels of ionizing radiation have created a movement in the radiology community to optimize computed tomography (CT) imaging protocols to use the lowest radiation dose possible without compromising the diagnostic usefulness of the images. Despite efforts to use appropriate and consistent radiation doses, studies suggest that a great deal of variability in radiation dose exists both within and between institutions for CT imaging. In this context, the authors have developed an automated size-specific radiation dose monitoring program for CT and used this program to assess variability in size-adjusted effective dose from CT imaging. The authors radiation dose monitoring program operates on an independent health insurance portability and accountability act compliant dosimetry server. Digital imaging and communication in medicine routing software is used to isolate dose report screen captures and scout images for all incoming CT studies. Effective dose conversion factors (k-factors) are determined based on the protocol and optical character recognition is used to extract the CT dose index and dose-length product. The patient's thickness is obtained by applying an adaptive thresholding algorithm to the scout images and is used to calculate the size-adjusted effective dose (ED(adj)). The radiation dose monitoring program was used to collect data on 6351 CT studies from three scanner models (GE Lightspeed Pro 16, GE Lightspeed VCT, and GE Definition CT750 HD) and two institutions over a one-month period and to analyze the variability in ED(adj) between scanner models and across institutions. No significant difference was found between computer measurements of patient thickness and observer measurements (p = 0.17), and the average difference between the two methods was less than 4%. Applying the size correction resulted in ED(adj) that differed by up to 44% from effective dose estimates that were not adjusted by patient size

  16. Development of computerized dose planning system and applicator for high dose rate remote afterloading irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, T. J. [Keimyung Univ., Taegu (Korea); Kim, S. W. [Fatima Hospital, Taegu (Korea); Kim, O. B.; Lee, H. J.; Won, C. H. [Keimyung Univ., Taegu (Korea); Yoon, S. M. [Dong-a Univ., Pusan (Korea)

    2000-04-01

    To design and fabricate of the high dose rate source and applicators which are tandem, ovoids and colpostat for OB/Gyn brachytherapy includes the computerized dose planning system. Designed the high dose rate Ir-192 source with nuclide atomic power irradiation and investigated the dose characteristics of fabricated brachysource. We performed the effect of self-absorption and determining the gamma constant and output factor and determined the apparent activity of designed source. he automated computer planning system provided the 2D distribution and 3D includes analysis programs. Created the high dose rate source Ir-192, 10 Ci(370GBq). The effective attenuation factor from the self-absorption and source wall was examined to 0.55 of the activity of bare source and this factor is useful for determination of the apparent activity and gamma constant 4.69 Rcm{sup 2}/mCi-hr. Fabricated the colpostat was investigated the dose distributions of frontal, axial and sagittal plane in intra-cavitary radiation therapy for cervical cancer. The reduce dose at bladder and rectum area was found about 20 % of original dose. The computerized brachytherapy planning system provides the 2-dimensional isodose and 3-D include the dose-volume histogram(DVH) with graphic-user-interface mode. emoted afterloading device was built for experiment of created Ir-192 source with film dosimetry within {+-}1 mm discrepancy. 34 refs., 25 figs., 11 tabs. (Author)

  17. Committed equivalent organ doses and committed effective doses from intakes of radionuclides

    CERN Document Server

    Phipps, A W; Kendall, G M; Silk, T J; Stather, J W

    1991-01-01

    This report contains details of committed equivalent doses to individual organs for intakes by ingestion and inhalation of 1 mu m AMAD particles of 359 nuclides by infants aged 3 months, by children aged 1, 5, 10 and 15 years, and by adults. It complements NRPB-R245 which describes the changes which have taken place since the last NRPB compendium of dose per unit intake factors (dose coefficients) and gives summary tables. Information on the way committed doses increase with the integration period is given in NRPB-M289. The information given in these memoranda is also available as a microcomputer package - NRPB-SR245.

  18. Computing proton dose to irregularly moving targets

    Science.gov (United States)

    Phillips, Justin; Gueorguiev, Gueorgui; Shackleford, James A.; Grassberger, Clemens; Dowdell, Stephen; Paganetti, Harald; Sharp, Gregory C.

    2014-08-01

    Purpose: While four-dimensional computed tomography (4DCT) and deformable registration can be used to assess the dose delivered to regularly moving targets, there are few methods available for irregularly moving targets. 4DCT captures an idealized waveform, but human respiration during treatment is characterized by gradual baseline shifts and other deviations from a periodic signal. This paper describes a method for computing the dose delivered to irregularly moving targets based on 1D or 3D waveforms captured at the time of delivery. Methods: The procedure uses CT or 4DCT images for dose calculation, and 1D or 3D respiratory waveforms of the target position at time of delivery. Dose volumes are converted from their Cartesian geometry into a beam-specific radiological depth space, parameterized in 2D by the beam aperture, and longitudinally by the radiological depth. In this new frame of reference, the proton doses are translated according to the motion found in the 1D or 3D trajectory. These translated dose volumes are weighted and summed, then transformed back into Cartesian space, yielding an estimate of the dose that includes the effect of the measured breathing motion. The method was validated using a synthetic lung phantom and a single representative patient CT. Simulated 4DCT was generated for the phantom with 2 cm peak-to-peak motion. Results: A passively-scattered proton treatment plan was generated using 6 mm and 5 mm smearing for the phantom and patient plans, respectively. The method was tested without motion, and with two simulated breathing signals: a 2 cm amplitude sinusoid, and a 2 cm amplitude sinusoid with 3 cm linear drift in the phantom. The tumor positions were equally weighted for the patient calculation. Motion-corrected dose was computed based on the mid-ventilation CT image in the phantom and the peak exhale position in the patient. Gamma evaluation was 97.8% without motion, 95.7% for 2 cm sinusoidal motion, 95.7% with 3 cm drift in the

  19. Evaluation of dose reduction and image quality in CT colonography: Comparison of low-dose CT with iterative reconstruction and routine-dose CT with filtered back projection

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Koichi [Kameda Medical Center, Department of Radiology, Kamogawa, Chiba (Japan); Jichi Medical University, Department of Radiology, Tochigi (Japan); National Cancer Center, Cancer Screening Technology Division, Research Center for Cancer Prevention and Screening, Tokyo (Japan); Fujiwara, Masanori; Mogi, Tomohiro; Iida, Nao [Kameda Medical Center Makuhari, Department of Radiology, Chiba (Japan); Kanazawa, Hidenori; Sugimoto, Hideharu [Jichi Medical University, Department of Radiology, Tochigi (Japan); Mitsushima, Toru [Kameda Medical Center Makuhari, Department of Gastroenterology, Chiba (Japan); Lefor, Alan T. [Jichi Medical University, Department of Surgery, Tochigi (Japan)

    2015-01-15

    To prospectively evaluate the radiation dose and image quality comparing low-dose CT colonography (CTC) reconstructed using different levels of iterative reconstruction techniques with routine-dose CTC reconstructed with filtered back projection. Following institutional ethics clearance and informed consent procedures, 210 patients underwent screening CTC using automatic tube current modulation for dual positions. Examinations were performed in the supine position with a routine-dose protocol and in the prone position, randomly applying four different low-dose protocols. Supine images were reconstructed with filtered back projection and prone images with iterative reconstruction. Two blinded observers assessed the image quality of endoluminal images. Image noise was quantitatively assessed by region-of-interest measurements. The mean effective dose in the supine series was 1.88 mSv using routine-dose CTC, compared to 0.92, 0.69, 0.57, and 0.46 mSv at four different low doses in the prone series (p < 0.01). Overall image quality and noise of low-dose CTC with iterative reconstruction were significantly improved compared to routine-dose CTC using filtered back projection. The lowest dose group had image quality comparable to routine-dose images. Low-dose CTC with iterative reconstruction reduces the radiation dose by 48.5 to 75.1 % without image quality degradation compared to routine-dose CTC with filtered back projection. (orig.)

  20. Agriculture-related radiation dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Furr, J.M.; Mayberry, J.J.; Waite, D.A.

    1987-10-01

    Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs.

  1. Pathogenic effects of low dose irradiation: dose-effect relationships; Effets pathogenes d'un faible debit de dose: la relation ''dose-effet

    Energy Technology Data Exchange (ETDEWEB)

    Masse, R. [Academie des Technologies, 91 - Saint Michel sur Orge (France)

    2002-10-01

    There is no evidence of pathogenic effects in human groups exposed to less than 100 mSv at low dose-rate. The attributed effects are therefore the result of extrapolations from higher doses. The validity of such extrapolations is discussed from the point of view of epidemiology as well as cellular and molecular biology. The Chernobyl accident resulted in large excess of thyroid cancers in children; it also raised the point that some actual sanitary effects among distressed populations might be a direct consequence of low doses. Studies under the control of UN have not confirmed this point identifying no dose-effect relationship and 'severe socio-economic and psychological pressures... poverty, poor diet and living conditions, and lifestyle factors' as the main cause for depressed health. Some hypothesis are considered for explaining the dose-dependence and high prevalence of non-cancer causes of death among human groups exposed to more than 300 mSv. (author)

  2. Occupational doses from radon in Spanish spas.

    Science.gov (United States)

    Soto, J; Gómez, J

    1999-04-01

    Recent international recommendations have included exposure to natural radiation as one of the sources to monitor in certain occupationally exposed groups. Among those mentioned are workers in thermal spas, who may be exposed to high radiation doses due to the high concentration of radon in the indoor air of the spa. This paper presents the methodology and the results of an evaluation of radiation doses to the staff in different thermal spas in Spain. Different series of samples were collected and measurements made for the radon concentrations in water in 54 spas and in air in 20 spas. In six of the latter group, the air radon concentration was studied in different working areas occupied by the employees. The radon concentrations in water were between radon concentrations in air were between radon concentration in their main working area. By means of an exposure-dose conversion factor of 1.43 Sv per J h m(-3), the estimated effective doses were found to lie between 1 and 44 mSv y(-1). This upper limit is higher than the recommended annual limit of 20 mSv y(-1) for an occupational dose.

  3. DRY TRANSFER FACILITY WORKER DOSE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    J.S. Tang

    2004-09-23

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Dry Transfer Facility No.1 (DTF-1) performing operations to receive transportation casks, transfer wastes, prepare waste packages, and ship out loaded waste packages and empty casks. Doses received by workers due to maintenance operations are also included in this revision. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation, excluding the remediation area of the building. The results of this calculation will be used to support the design of the DTF-1 and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in the Environmental and Nuclear Engineering.

  4. Optimizing Radiation Doses for Computed Tomography Across Institutions: Dose Auditing and Best Practices.

    Science.gov (United States)

    Demb, Joshua; Chu, Philip; Nelson, Thomas; Hall, David; Seibert, Anthony; Lamba, Ramit; Boone, John; Krishnam, Mayil; Cagnon, Christopher; Bostani, Maryam; Gould, Robert; Miglioretti, Diana; Smith-Bindman, Rebecca

    2017-06-01

    Radiation doses for computed tomography (CT) vary substantially across institutions. To assess the impact of institutional-level audit and collaborative efforts to share best practices on CT radiation doses across 5 University of California (UC) medical centers. In this before/after interventional study, we prospectively collected radiation dose metrics on all diagnostic CT examinations performed between October 1, 2013, and December 31, 2014, at 5 medical centers. Using data from January to March (baseline), we created audit reports detailing the distribution of radiation dose metrics for chest, abdomen, and head CT scans. In April, we shared reports with the medical centers and invited radiology professionals from the centers to a 1.5-day in-person meeting to review reports and share best practices. We calculated changes in mean effective dose 12 weeks before and after the audits and meeting, excluding a 12-week implementation period when medical centers could make changes. We compared proportions of examinations exceeding previously published benchmarks at baseline and following the audit and meeting, and calculated changes in proportion of examinations exceeding benchmarks. Of 158 274 diagnostic CT scans performed in the study period, 29 594 CT scans were performed in the 3 months before and 32 839 CT scans were performed 12 to 24 weeks after the audit and meeting. Reductions in mean effective dose were considerable for chest and abdomen. Mean effective dose for chest CT decreased from 13.2 to 10.7 mSv (18.9% reduction; 95% CI, 18.0%-19.8%). Reductions at individual medical centers ranged from 3.8% to 23.5%. The mean effective dose for abdominal CT decreased from 20.0 to 15.0 mSv (25.0% reduction; 95% CI, 24.3%-25.8%). Reductions at individual medical centers ranged from 10.8% to 34.7%. The number of CT scans that had an effective dose measurement that exceeded benchmarks was reduced considerably by 48% and 54% for chest and abdomen, respectively. After

  5. Radiation dose metrics in CT: assessing dose using the National Quality Forum CT patient safety measure.

    Science.gov (United States)

    Keegan, Jillian; Miglioretti, Diana L; Gould, Robert; Donnelly, Lane F; Wilson, Nicole D; Smith-Bindman, Rebecca

    2014-03-01

    The National Quality Forum (NQF) is a nonprofit consensus organization that recently endorsed a measure focused on CT radiation doses. To comply, facilities must summarize the doses from consecutive scans within age and anatomic area strata and report the data in the medical record. Our purpose was to assess the time needed to assemble the data and to demonstrate how review of such data permits a facility to understand doses. To assemble the data we used for analysis, we used the dose monitoring software eXposure to automatically export dose metrics from consecutive scans in 2010 and 2012. For a subset of 50 exams, we also collected dose metrics manually, copying data directly from the PACS into an excel spreadsheet. Manual data collection for 50 scans required 2 hours and 15 minutes. eXposure compiled the data in under an hour. All dose metrics demonstrated a 30% to 50% reduction between 2010 and 2012. There was also a significant decline and a reduction in the variability of the doses over time. The NQF measure facilitates an institution's capacity to assess the doses they are using for CT as part of routine practice. The necessary data can be collected within a reasonable amount of time either with automatic software or manually. The collection and review of these data will allow facilities to compare their radiation dose distributions with national distributions and allow assessment of temporal trends in the doses they are using. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  6. Effect of Dose Rate Variation on Dose Distribution in IMRT with a Dynamic Multileaf Collimator

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Kyoung Dal; Jae, Young Wan; Yoon, Il Kyu; Lee, Jae Hee; Yoo, Suk Hyun [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2012-03-15

    To evaluate dose distribution differences when the dose rates are randomly changed in intensity-modulated radiation therapy using a dynamic multileaf collimator. Two IMRT treatment plans including small-field and large-field plans were made using a commercial treatment planning system (Eclipse, Varian, Palo Alto, CA). Each plan had three sub-plans according to various dose rates of 100, 400, and 600 MU/min. A chamber array (2D-Array Seven729, PTW-Freiburg) was positioned between solid water phantom slabs to give measurement depth of 5 cm and backscattering depth of 5 cm. Beam deliveries were performed on the array detector using a 6 MV beam of a linear accelerator (Clinac 21EX, Varian, Palo Alto, CA) equipped with 120-leaf MLC (Millenium 120, Varian). At first, the beam was delivered with same dose rates as planned to obtain reference values. After the standard measurements, dose rates were then changed as follows: 1) for plans with 100 MU/min, dose rate was varied to 200, 300, 400, 500 and 600 MU/min, 2) for plans with 400 MU/min, dose rate was varied to 100, 200, 300, 500 and 600 MU/min, 3) for plans with 600 MU/min, dose rate was varied to 100, 200, 300, 400 and 500 MU/min. Finally, using an analysis software (Verisoft 3.1, PTW-Freiburg), the dose difference and distribution between the reference and dose-rate-varied measurements was evaluated. For the small field plan, the local dose differences were -0.8, -1.1, -1.3, -1.5, and -1.6% for the dose rate of 200, 300, 400, 500, 600 MU/min, respectively (for 100 MU/min reference), +0.9, +0.3, +0.1, -0.2, and -0.2% for the dose rate of 100, 200, 300, 500, 600 MU/min, respectively (for 400 MU/min reference) and +1.4, +0.8, +0.5, +0.3, and +0.2% for the dose rate of 100, 200, 300, 400, 500 MU/min, respectively (for 600 MU/min reference). On the other hand, for the large field plan, the pass-rate differences were -1.3, -1.6, -1.8, -2.0, and -2.4% for the dose rate of 200, 300, 400, 500, 600 MU/min, respectively (for 100

  7. Determinants of thiopental induction dose requirements.

    Science.gov (United States)

    Avram, M J; Sanghvi, R; Henthorn, T K; Krejcie, T C; Shanks, C A; Fragen, R J; Howard, K A; Kaczynski, D A

    1993-01-01

    Dose requirements for thiopental anesthetic induction have significant age- and gender-related variability. We studied the association of the patient characteristics age, gender, weight, lean body mass, and cardiac output with thiopental requirements. Doses of thiopental, infused at 150 mg/min, required to reach both a clinical end-point and an electroencephalographic (EEG) end-point were determined in 30 males and 30 females, aged 18-83 yr. Univariate least squares linear regression analysis revealed outliers in the relationships of age, weight, lean body mass, and cardiac output to thiopental dose at clinical and EEG endpoints. Differential weighting of data points minimized the effect of outliers in the construction of a robust multiple linear regression model of the relationship between several selected independent variables and the dependent variables thiopental dose at clinical and EEG endpoints. The multiple linear regression model for thiopental dose at the clinical end-point selecting the regressor variables age, weight, and gender (R2 = 0.76) was similar to that for age, lean body mass, and gender (R2 = 0.75). Thiopental dose at the EEG endpoint was better described by models selecting the variables age, weight, and cardiac output (R2 = 0.88) or age, lean body mass, and cardiac output (R2 = 0.87). Although cardiac output varied with age, age always remained a selected variable. Because weight and lean body mass differed with gender, their selection as variables in the model eliminated gender as a selected variable or minimized its importance.

  8. Measuring pacemaker dose: A clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Studenski, Matthew T., E-mail: matthew.studenski@jeffersonhospital.org [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Xiao Ying; Harrison, Amy S. [Department of Radiation Oncology at the Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2012-07-01

    Recently in our clinic, we have seen an increased number of patients presenting with pacemakers and defibrillators. Precautions are taken to develop a treatment plan that minimizes the dose to the pacemaker because of the adverse effects of radiation on the electronics. Here we analyze different dosimeters to determine which is the most accurate in measuring pacemaker or defibrillator dose while at the same time not requiring a significant investment in time to maintain an efficient workflow in the clinic. The dosimeters analyzed here were ion chambers, diodes, metal-oxide-semiconductor field effect transistor (MOSFETs), and optically stimulated luminescence (OSL) dosimeters. A simple phantom was used to quantify the angular and energy dependence of each dosimeter. Next, 8 patients plans were delivered to a Rando phantom with all the dosimeters located where the pacemaker would be, and the measurements were compared with the predicted dose. A cone beam computed tomography (CBCT) image was obtained to determine the dosimeter response in the kilovoltage energy range. In terms of the angular and energy dependence of the dosimeters, the ion chamber and diode were the most stable. For the clinical cases, all the dosimeters match relatively well with the predicted dose, although the ideal dosimeter to use is case dependent. The dosimeters, especially the MOSFETS, tend to be less accurate for the plans, with many lateral beams. Because of their efficiency, we recommend using a MOSFET or a diode to measure the dose. If a discrepancy is observed between the measured and expected dose (especially when the pacemaker to field edge is <10 cm), we recommend analyzing the treatment plan to see whether there are many lateral beams. Follow-up with another dosimeter rather than repeating multiple times with the same type of dosimeter. All dosimeters should be placed after the CBCT has been acquired.

  9. Therapeutic effects of low radiation doses

    Energy Technology Data Exchange (ETDEWEB)

    Trott, K.R. (Dept. of Radiation Biology, St. Bartholomew' s Medical College, London (United Kingdom))

    1994-01-01

    This editorial explores the scientific basis of radiotherapy with doses of < 1 Gy for various non-malignant conditions, in particular dose-effect relationships, risk-benefit considerations and biological mechanisms. A review of the literature, particularly clinical and experimental reports published more than 50 years ago was conducted to clarify the following problems. 1. The dose-response relationships for the therapeutic effects on three groups of conditions: non-malignant skin disease, arthrosis and other painful degenerative joint disorders and anti-inflammatory radiotherapy; 2. risks after radiotherapy and after the best alternative treatments; 3. the biological mechanisms of the different therapeutic effects. Radiotherapy is very effective in all three groups of disease. Few dose-finding studies have been performed, all demonstrating that the optimal doses are considerable lower than the generally recommended doses. In different conditions, risk-benefit analysis of radiotherapy versus the best alternative treatment yields very different results: whereas radiotherapy for acute postpartum mastitis may not be justified any more, the risk-benefit ratio of radiotherapy of other conditions and particularly so in dermatology and some anti-inflammatory radiotherapy appears to be more favourable than the risk-benefit ratio of the best alternative treatments. Radiotherapy can be very effective treatment for various non-malignant conditions such as eczema, psoriasis, periarthritis humeroscapularis, epicondylitis, knee arthrosis, hydradenitis, parotitis and panaritium and probably be associated with less acute and long-term side effects than similarly effective other treatments. Randomized clinical studies are required to find the optimal dosage which, at present, may be unnecessarily high.

  10. Fertility of tall girls treated with high-dose estrogen, a dose-response relationship

    NARCIS (Netherlands)

    A.E.J. Hendriks (Emile); S.L.S. Drop (Stenvert); J.S.E. Laven (Joop); A.M. Boot (Annemieke)

    2012-01-01

    textabstractContext: High-dose estrogen treatment to reduce final height of tall girls increases their risk for infertility in later life. Objective: The aim was to study the effect of estrogen dose on fertility outcome of these women. Design/Setting: We conducted a retrospective cohort study of

  11. A CONCEPTUAL FRAMEWORK FOR MANAGING RADIATION DOSE TO PATIENTS IN DIAGNOSTIC RADIOLOGY USING REFERENCE DOSE LEVELS.

    Science.gov (United States)

    Almén, Anja; Båth, Magnus

    2016-06-01

    The overall aim of the present work was to develop a conceptual framework for managing radiation dose in diagnostic radiology with the intention to support optimisation. An optimisation process was first derived. The framework for managing radiation dose, based on the derived optimisation process, was then outlined. The outset of the optimisation process is four stages: providing equipment, establishing methodology, performing examinations and ensuring quality. The optimisation process comprises a series of activities and actions at these stages. The current system of diagnostic reference levels is an activity in the last stage, ensuring quality. The system becomes a reactive activity only to a certain extent engaging the core activity in the radiology department, performing examinations. Three reference dose levels-possible, expected and established-were assigned to the three stages in the optimisation process, excluding ensuring quality. A reasonably achievable dose range is also derived, indicating an acceptable deviation from the established dose level. A reasonable radiation dose for a single patient is within this range. The suggested framework for managing radiation dose should be regarded as one part of the optimisation process. The optimisation process constitutes a variety of complementary activities, where managing radiation dose is only one part. This emphasises the need to take a holistic approach integrating the optimisation process in different clinical activities. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Assessment of dose uniformity around high dose rate 192Ir and 60Co stepping sources.

    Science.gov (United States)

    Farhood, Bagher; Ghorbani, Mahdi

    2017-12-01

    This study aimed to evaluate dose uniformity for 192Ir and 60Co stepping sources. High dose rate 192Ir and 60Co stepping sources were simulated by the MCNPX Monte Carlo code. To investigate dose uniformity, treatment lengths of 30, 50, 100, and 150 mm with stepping distances of 3, 5, 7, and 10 mm were considered. Finally, dose uniformity for the 192Ir and 60Co stepping sources with increasing distances from the source were assessed at these treatment lengths and steps. The findings showed that the dose distribution was non-uniform for regions in close vicinity of the source, especially in the high source steps, but for most points at distances >10 mm from the center of the source, the dose distribution was uniform. For most points, the dose uniformity increased with reduction of the source steps and increments of the transverse distance from the source. The dose non-uniformity was similar for most of the corresponding points of 60Co and 192Ir sources with the same treatment lengths and source steps, except at the distance of 150 mm. When using stepping technique for the treatment of tumors, more attention should be focused on treatment planning, especially with higher stepping distances and lower transverse distances from the source.

  13. A review of dose rate dependent effects of total ionizing dose /TID/ irradiations. [on semiconductor devices

    Science.gov (United States)

    Nichols, D. K.

    1980-01-01

    The basic effects of ionizing radiation are summarized. The problem of the existence of a true dose rate effect is examined. Consideration is given to the nature of long term annealing, which is sometimes manifested as an 'apparent' dose rate effect. Both analytical and experimental work is considered and the results are related to practical testing requirements.

  14. Lurasidone Dose Response in Bipolar Depression: A Population Dose-response Analysis.

    Science.gov (United States)

    Chapel, Sunny; Chiu, Yu-Yuan; Hsu, Jay; Cucchiaro, Josephine; Loebel, Antony

    2016-01-01

    Characterization of dose-response relationships for psychotropic agents may be difficult to determine based on results of individual clinical studies, particularly those with a flexible dose design. The goal of this pharmacometric analysis was to characterize the dose-response profile for lurasidone in patients with bipolar depression. The statistical modeling and simulation analyses reported here were derived from 2 randomized, 6-week, double-blind, placebo-controlled, flexible-dose studies (20-60 mg/d or 80-120 mg/d of lurasidone as monotherapy or 20-120 mg/d adjunct to lithium or valproate) in patients with bipolar depression. Pooled data included 5245 Montgomery-Åsberg Depression Rating Scale (MADRS) observations from 825 patients who had received lurasidone or placebo treatments, with or without lithium or valproate background medication. The time course of placebo effect on the MADRS score was adequately described by an exponential asymptotic placebo model. A linear dose-response model best described the effect of lurasidone. The net improvement in MADRS score due to lurasidone treatment (the drug effect) was significant (P related to demographic covariates. This population dose-response modeling analysis indicates that higher doses of lurasidone are likely to produce greater therapeutic effects in patients with bipolar depression. The linear dose response was consistent for both lurasidone monotherapy and adjunctive therapy in patients with bipolar depression. ClinicalTrials.gov identifiers: NCT00868452, NCT00868699. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Chlorpromazine equivalents versus defined daily doses : How to compare antipsychotic drug doses?

    NARCIS (Netherlands)

    Rijcken, CAW; Monster, TBM; Brouwers, JRBJ; de Jong-van den Berg, LTW

    2003-01-01

    Classic chlorpromazine (CPZ) equivalents can be used to chart relative antipsychotic potencies of antipsychotic drugs. Values of CPZ equivalents per drug are ambiguous in literature. In drug use evaluation studies, antipsychotic doses are frequently compared by use of the defined daily dose (DDD).

  16. Fertility of Tall Girls Treated with High-Dose Estrogen, a Dose-Response Relationship

    NARC